Mapping Cellular Gains and Losses in the Postnatal Dentate Gyrus: Implications for Psychiatric Disorders

Experimental Neurology. Aug, 2006  |  Pubmed ID: 16624303

Neurogenesis and apoptosis occur contemporaneously in the postnatal hippocampal dentate gyrus and have been implicated in mood and cognitive disorders. Particularly, neurogenesis correlates with the manifestation of antidepressant effects, but its quantitative and topographical relationship with concomitant cell death has not been investigated. Accordingly, we applied stereological measurements to obtain synchronized topographical maps of these two events in rats aged 1 and 3 months under basal conditions; the two ages were chosen to represent neuro-developmental windows during which cell proliferation and death are occurring at peak and relatively steady levels, respectively. Our analysis shows that apoptotic cells are evenly distributed throughout the dentate gyrus, although the incidence of apoptosis decreased gradient-wise from the tip of the suprapyramidal layer and was highest in the external third of the granule cell layer. Interestingly, apoptosis was higher in the left hippocampus. In addition, we confirm previous less stringent studies demonstrating that neurogenesis occurs differentially in the dorsal-ventral axis of the hippocampus and in suprapyramidal-infrapyramidal blades of the dentate gyrus. These results raise intriguing new questions regarding the coordinated regulation of hippocampal neurogenesis and apoptosis since the two processes apparently share common regulatory factors. In addition, these findings open questions with respect to the functional significance of topographical gradients in neurogenesis and apoptosis in the context of the etiopathogenesis of neuropsychiatric diseases and the reported dependence on the efficacy of therapeutic agents on the generation of new hippocampal neurons.

Sequence Analysis of Coat Protein Gene of Wuhan Nodavirus Isolated from Insect

Virus Research. Oct, 2006  |  Pubmed ID: 16644053

Wuhan nodavirus (WhNV) particles are isometric, non-enveloped, and about 29 nm in diameter. In the previous study, we determine its physiochemical characterization and the nucleotide sequence of the larger genomic segment, RNA1 and identify it a nodavirus. WhNV RNA1 is 3,149 nt in length, encoding protein A, catalytic subunit of RNA-dependent RNA polymerase (RdRp). In this report, we complete the sequence determination of the smaller genomic segment, RNA2 of WhNV. WhNV RNA2 is determined to be 1,562 nt long, containing a 430-amino-acid open reading frame (ORF) encoding the coat protein of WhNV with a calculated molecular mass of 47,856 Da. The homology of the coat protein of WhNV and the homologous proteins of other nodaviruses either alphanodaviruses or betanodaviruses is very low. WhNV coat protein shares the highest identity (24%) with that of Lates calcarifer encephalitis virus (LCEV), a betanodavirus, and shares less than 16% identical amino acids with each of the alphanodaviruses. Furthermore, the prediction of WhNV capsid structure by 3D-PSSM shows that the capsid structure of WhNV resembles that of tomato bushy stunt virus (TBSV), a tombusvirus, which contains two domains, rather than the expected single-domain capsid protein of insect nodaviruses. The phylogenetic analysis indicates that WhNV is the most distantly related of both the alphanodaviruses and betanodaviruses, which provides significant new data for understanding the evolution of the nodavirus family.

Isolation and Characterization of the First Putative Peroxidase Gene from Oilseed Rape (Brassica Napus) Which is Highly Homologous to HRPC

Bioscience Reports. Jun, 2006  |  Pubmed ID: 16855866

A new gene, designated as BnPrx (GenBank Accession No. DQ078754), was isolated from oilseed rape (Brassica napus) by SMART Rapid Amplification of cDNA Ends (RACE). The full-length cDNA is 1307 bp long and contains a 1062 bp open reading frame (ORF), which encodes a 354 amino acid peroxidase precursor, with a 31 aa N-terminal signal peptide and a 15 aa C-terminal propeptide. The putative protein has a molecular weight of 38.86 kDa and a calculated pI of 5.85. BnPrx shares high identity with HRPC (89%). BnPrx possesses all active residues and two Ca(2+) sites present in Horseradish peroxidase isoenzymes C (HRPC) as well as six N-glycosylation sites. The predicted 3-D structure of BnPrx is very similar to that of HRPC. Assisted by genomic walking technology, the genomic DNA of BnPrx was also cloned, consisting of 3 introns and 4 exons. Thirty-two TATA boxes, 18 CAAT boxes and many cis-elements, such as WUN, MeJR, were found in its promoter region. Southern blot analysis indicated that BnPrx belonged to a small gene family. Northern blot analysis revealed that BnPrx was constitutively expressed in all tested tissues, including roots, stems and leaves, with the high expression in leaves and stems. The expression of BnPrx could be induced by methyl jasmonate (MeJA), salicylic acid (SA), cold and H(2)O(2). The cloning and characterizing of BnPrx might not only help us understand the physiological function and molecular evolution of the large peroxidase gene family more comprehensively, but also provide an alternative way of seeking a more effective and economical substitute for HRPC.

[Purification and Characterization of Weak-acid Antibacterial Peptide MD7095 from Musca Domestica Larvae]

Wei Sheng Wu Xue Bao = Acta Microbiologica Sinica. Jun, 2006  |  Pubmed ID: 16933610

Musca domestica,which belongs to insecta, diptera, cyclorrhapha, muscidae, is the most common muscae and the richest resource. It is very significant and valuable to isolate antibacterial peptides from Musca domestica and to develop these peptides into antibacterial medicine. Due to purify a pure peptide from the natural materials (animal, plant and microorganism tissue) is very difficult and complex, few research is going on. It had been reported that the most antibacterial peptides from Musca domestica were alkaline, no weak-acid antibacterial peptides had been reported so far. Based on a high sensitivity detection method, using dilute acetic acid extraction, alginic acid absorption, NaCl salting-out, Sephadex G-25 gel filtration, CMC23 ion-exchange chromatography, electrophoresis, a group of weak-acid antibacterial peptides had been purified from Musca domestica larvae and partial characterized. The peptides had characters of broad antibacterial spectrum and low minimum bactericidal concentration against Gram-positive bacterium such as Bacillus thuringiensis, Bacillus subtilis, Staphylococcus aureus and Gram-negative bacterium such as Pseudomonas aeruginosa, Escherichia coli. The peptides were very stable to keep the antibacterial activity even kept in 95 degrees C for 120 min and frozen-thawed for 10 times. A weak-acid antibacterial peptide MD7095 had been purified in high degree of purity by electro-elution,and was determined Mr 7095Da with MALDI-TOF-MS and pl 5.59 with IEF-PAGE. Peptide mass fingerprinting (PMF) analysis showed MD7095 was a novel bioactive peptide. Few peptides with antibacterial activity against Bacillus thuringiensis had been reported. Observation by scanning electron microscopy (SEM), it was suggested that the bioactivity mechanism of antibacterial peptides from Musca domestica larvae against Bacillus thuringiensis was to perforate cell membrane and lead to bacterium lysis and die. It is hopeful to develop the antibacterial peptides from Musca domestica to candidate medicine.

[Effects of Gantry Position on the Accuracy of Lead Block Localization and Relative Quality Control Methods]

Ai Zheng = Aizheng = Chinese Journal of Cancer. Sep, 2006  |  Pubmed ID: 16965667

To date, the low-melting point lead blocks are commonly used as a beam modifier for the accurate three-dimensional (3D) radiotherapy in China. However, care should be taken when using blocks even though they are verified on the specified simulator or linear accelerator before treatment. This is because that those verifications are only performed under the gantry angle of 0 degree. For the oblique gantry angles, the block may shift in the tray leading to the positioning error. In this study, we explored the influence of gantry position on the accuracy of lead block localization, and the relative quality control methods were also provided.

[Studies on the Effect of Extracts of Several Chinese Herbal Medicines and Other Medicines on Alcohol Dehydrogenase Activity]

Zhong Yao Cai = Zhongyaocai = Journal of Chinese Medicinal Materials. Aug, 2006  |  Pubmed ID: 17076243

To study the effects of water and alcohol extracts of several Chinese herbal medicines and other medicines on alcohol dehydrogenase activity in order to provide enzymology basis on new medicine.

In Vitro and in Vivo Identification of Structural and Sequence Elements in the 5' Untranslated Region of Ectropis Obliqua Picorna-like Virus Required for Internal Initiation

The Journal of General Virology. Dec, 2006  |  Pubmed ID: 17098984

Ectropis obliqua picorna-like virus (EoPV) is a newly described insect virus that is classified as a putative member of the genus Iflavirus. The virus possesses a large, positive-sense RNA genome encoding a single polyprotein that shares physicochemical properties with those of members of the family Picornaviridae. The 5' untranslated region (5' UTR) plays an important role in picornavirus translation initiation, as it contains an internal ribosome entry site (IRES) that mediates cap-independent translation. To investigate translation in EoPV, an extensive range of mutations were engineered within the 5' UTR and the effects of these changes were examined in vitro and in vivo by using a bicistronic construct. Results showed that deletions within the first 63 nt had little impact on IRES activity, whilst core IRES function was contained within stem-loops C and D, as their removal abrogated IRES activity significantly. In contrast to these findings, removal of stem-loop G containing two cryptic AUGs caused a remarkable increase in IRES activity, which was further investigated by site-directed mutagenesis at these two positions. It was also confirmed that initiation of protein synthesis occurs at AUG6 (position 391-394) and not at the AUG immediately downstream of the polypyrimidine tract. Mutation of the polypyrimidine tract (CCTTTC) had a slight effect on EoPV IRES activity. Furthermore, mutations of the RAAA motif led to a decrease in IRES activity of approximately 40 % in vitro, but these results were not supported by in vivo experiments. In conclusion, this study reveals that the EoPV IRES element is unique, although it has features in common with the type II IRESs.

[Mechanisms of Arsenic Trioxide Induced Tumor Cell Apoptosis in Myelodysplastic Syndrome Mice Model in Vivo]

Zhonghua Er Ke Za Zhi. Chinese Journal of Pediatrics. Oct, 2006  |  Pubmed ID: 17229386

To explore the possible mechanisms of cell apoptosis induced by arsenic trioxide (ATO) alone or in combination with thalidomide (THAL) on SCID mice model transplanted with human myelodysplastic syndrome (MDS) cell line MUTZ-1 in vivo.

Activity of the Plant Peptide Aglycin in Mammalian Systems

The FEBS Journal. Feb, 2007  |  Pubmed ID: 17288555

A 37 residue peptide, aglycin, has been purified from porcine intestine. The sequence is identical to that of residues 27-63 of plant albumin 1 B precursor (PA1B, chain b) from pea seeds. Aglycin resists in vitro proteolysis by pepsin, trypsin and Glu-C protease, compatible with its intestinal occurrence and an exogenous origin from plant food. When subcutaneously injected into mice (at 10 microg.g(-1) body weight), aglycin has a hyperglycemic effect resulting in a doubling of the blood glucose level within 60 min. Using surface plasmon resonance biosensor technology, an aglycin binding protein with an apparent molecular mass of 34 kDa was detected in membrane protein extracts from porcine and mice pancreas. The polypeptide was purified by affinity chromatography and identified through peptide mass fingerprinting as the voltage-dependent anion-selective channel protein 1. The results indicate that aglycin has the potential to interfere with mammalian physiology.

Robust Immunohistochemical Staining of Several Classes of Proteins in Tissues Subjected to Autolysis

The Journal of Histochemistry and Cytochemistry : Official Journal of the Histochemistry Society. Jun, 2007  |  Pubmed ID: 17312010

Despite the common use of immunohistochemistry in autopsy tissues, the stability of most proteins over extended time periods is unknown. The robustness of signal for 16 proteins (MMP1, MMP2, MMP3, MMP9, TIMP1, TIMP2, TIMP3, AGER, MSR, SCARB1, OLR1, CD36, LTF, LGALS3, LYZ, and DDOST) and two measures of advanced glycation end products (AGE, CML) was evaluated. Two formalin-fixed, paraffin-embedded human tissue arrays containing 16 tissues each were created to evaluate 48 hr of autolysis in a warm or cold environment. For these classes of proteins, matrix metalloproteinases and their inhibitors, scavenger receptors, and advanced glycation end product receptors, we saw no systematic diminution of signal intensity during a period of 24 hr. Analysis was performed by two independent observers and confirmed for a subset of proteins by digital analysis and Western blotting. We conclude that these classes of proteins degrade slowly and faithfully maintain their immunohistochemistry characteristics over at least a 24-hr time interval in devitalized tissues. This study supports the use of autopsy tissues with short postmortem intervals for immunohistochemical studies for diseases such as diabetic vascular disease, cancer, Alzheimer's disease, atherosclerosis, and other pathological states. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.

LTP Inhibits LTD in the Hippocampus Via Regulation of GSK3beta

Neuron. Mar, 2007  |  Pubmed ID: 17329210

Glycogen synthase kinase-3 (GSK3) has been implicated in major neurological disorders, but its role in normal neuronal function is largely unknown. Here we show that GSK3beta mediates an interaction between two major forms of synaptic plasticity in the brain, N-methyl-D-aspartate (NMDA) receptor-dependent long-term potentiation (LTP) and NMDA receptor-dependent long-term depression (LTD). In rat hippocampal slices, GSK3beta inhibitors block the induction of LTD. Furthermore, the activity of GSK3beta is enhanced during LTD via activation of PP1. Conversely, following the induction of LTP, there is inhibition of GSK3beta activity. This regulation of GSK3beta during LTP involves activation of NMDA receptors and the PI3K-Akt pathway and disrupts the ability of synapses to undergo LTD for up to 1 hr. We conclude that the regulation of GSK3beta activity provides a powerful mechanism to preserve information encoded during LTP from erasure by subsequent LTD, perhaps thereby permitting the initial consolidation of learnt information.

Dual Role for SUMO E2 Conjugase Ubc9 in Modulating the Transforming and Growth-promoting Properties of the HMGA1b Architectural Transcription Factor

The Journal of Biological Chemistry. May, 2007  |  Pubmed ID: 17350957

Members of the HMGA1 (high mobility group A1) family of architectural transcription factors, HMGA1a and HMGA1b, play important roles in many normal cellular processes and in tumorigenesis. We performed a yeast two-hybrid screen for HMGA1-interacting proteins and identified the SUMO E2 conjugase Ubc9 as one such partner. The Ubc9-interacting domain of HMGA1 is bipartite, consisting of a proline-rich region near the N terminus and an acidic domain at the extreme C terminus, whereas the HMGA1-interacting domain of Ubc9 comprises a single region previously shown to associate with and SUMOylate other transcription factors. Consistent with these findings, endogenous HMGA1 proteins and Ubc9 could be co-immunoprecipitated from several human cell lines. Studies with HMGA1b proteins containing mutations of either or both Ubc9-interacting domains and with Ubc9-depleted cell lines indicated that the proline-rich domain of HMGA1b positively influences transformation and growth, whereas the acidic domain negatively influences these properties. None of the changes in HMGA1 protein functions mediated by Ubc9 appears to require SUMOylation. These findings are consistent with the idea that Ubc9 can act as both a positive and negative regulator of proliferation and transformation via its non-SUMO-dependent interaction with HMGA1 proteins.

C-Myc-mediated Genomic Instability Proceeds Via a Megakaryocytic Endomitosis Pathway Involving Gp1balpha

Proceedings of the National Academy of Sciences of the United States of America. Feb, 2007  |  Pubmed ID: 17360671

Genomic instability (GI) is essential for the initiation and evolution of many cancers and often precedes frank neoplastic conversion. Although GI can occur at several levels, the most conspicuous examples involve gains or losses of entire chromosomes (aneuploidy), the antecedent of which may be whole genome duplication (tetraploidy). Through largely undefined mechanisms, the c-Myc oncoprotein and its downstream target, MTMC1, promote tetraploidy and other forms of GI. In myeloid cells, c-Myc and MTMC1 also regulate a common, small subset of c-Myc target genes including GP1Balpha, which encodes a subunit of the von Willebrand's factor receptor complex that mediates platelet adhesion and aggregation. Gp1balpha also participates in megakaryocyte endomitosis, a form of controlled and precise whole-genome amplification. In this article, we show that both c-Myc and MTMC1 strongly up-regulate Gp1balpha concurrent with their promotion of tetraploidy. shRNA-mediated inhibition of Gp1balpha prevents tetraploidy by both c-Myc and MTMC1, whereas Gp1balpha overexpression alone is sufficient to induce tetraploidy in established and primary cells. Once acquired, tetraploidy persists in most cases examined. Our results indicate that chromosome-level GI, induced by c-Myc overexpression, proceeds by means of the sequential up-regulation of MTMC1 and Gp1balpha and further suggest that the pathways leading to megakaryocytic endomitosis and c-Myc-induced tetraploidy are mechanistically linked by their reliance on Gp1balpha.

NMDA Receptor Subunits Have Differential Roles in Mediating Excitotoxic Neuronal Death Both in Vitro and in Vivo

The Journal of Neuroscience : the Official Journal of the Society for Neuroscience. Mar, 2007  |  Pubmed ID: 17360906

Well-documented experimental evidence from both in vitro and in vivo models of stroke strongly supports the critical involvement of NMDA receptor-mediated excitotoxicity in neuronal damage after stroke. Despite this, the results of clinical trials testing NMDA receptor antagonists as neuroprotectants after stroke and brain trauma have been discouraging. Here, we report that in mature cortical cultures, activation of either synaptic or extrasynaptic NR2B-containing NMDA receptors results in excitotoxicity, increasing neuronal apoptosis. In contrast, activation of either synaptic or extrasynaptic NR2A-containing NMDA receptors promotes neuronal survival and exerts a neuroprotective action against both NMDA receptor-mediated and non-NMDA receptor-mediated neuronal damage. A similar opposing action of NR2B and NR2A in mediating cell death and cell survival was also observed in an in vivo rat model of focal ischemic stroke. Moreover, we found that blocking NR2B-mediated cell death was effective in reducing infarct volume only when the receptor antagonist was given before the onset of stroke and not 4.5 h after stroke. In great contrast, activation of NR2A-mediated cell survival signaling with administration of either glycine alone or in the presence of NR2B antagonist significantly attenuated ischemic brain damage even when delivered 4.5 h after stroke onset. Together, the present work provides a molecular basis for the dual roles of NMDA receptors in promoting neuronal survival and mediating neuronal damage and suggests that selective enhancement of NR2A-containing NMDA receptor activation with glycine may constitute a promising therapy for stroke.

Dynamic Susceptibility Contrast Perfusion Magnetic Resonance Imaging in Patients with Symptomatic Unilateral Middle Cerebral Artery Stenosis or Occlusion

Acta Radiologica (Stockholm, Sweden : 1987). Apr, 2007  |  Pubmed ID: 17453507

To evaluate cerebral hemodynamic disturbance in patients with symptomatic unilateral middle cerebral artery (MCA) high-grade stenosis or occlusion using dynamic susceptibility contrast perfusion magnetic resonance imaging (DSC-pMRI).

Filamin B Mutations Cause Chondrocyte Defects in Skeletal Development

Human Molecular Genetics. Jul, 2007  |  Pubmed ID: 17510210

Filamin B (FLNB) is a cytoplasmic protein that regulates the cytoskeletal network by cross-linking actin, linking cell membrane to the cytoskeleton and regulating intracellular signaling pathways responsible for skeletal development (Stossel, T.P., Condeelis, J., Cooley, L., Hartwig, J.H., Noegel, A., Schleicher, M. and Shapiro, S.S. (2001) Filamins as integrators of cell mechanics and signalling. Nat. Rev. Mol. Cell Biol., 2, 138-145). Mutations in FLNB cause human skeletal disorders [boomerang dysplasia, spondylocarpotarsal (SCT), Larsen, and atelosteogenesis I/III syndromes], which are characterized by disrupted vertebral segmentation, joint formation and endochondral ossification [Krakow, D., Robertson, S.P., King, L.M., Morgan, T., Sebald, E.T., Bertolotto, C., Wachsmann-Hogiu, S., Acuna, D., Shapiro, S.S., Takafuta, T. et al. (2004) Mutations in the gene encoding filamin B disrupt vertebral segmentation, joint formation and skeletogenesis. Nat. Genet., 36, 405-410; Bicknell, L.S., Morgan, T., Bonafe, L., Wessels, M.W., Bialer, M.G., Willems, P.J., Cohn, D.H., Krakow, D. and Robertson, S.P. (2005) Mutations in FLNB cause boomerang dysplasia. J. Med. Genet., 42, e43]. Here we show that Flnb deficient mice have shortened distal limbs with small body size, and develop fusion of the ribs and vertebrae, abnormal spinal curvatures, and dysmorphic facial/calvarial bones, similar to the human phenotype. Characterization of the mutant mice demonstrated increased apoptosis along the bone periphery of the distal appendages, consistent with reduced bone width. No changes in the initial proliferative rate of chondrocytes were observed, but the progressive differentiation of chondrocyte precursors was impaired, consistent with reduced bone length. The extracellular matrix appeared disrupted and phosphorylated beta1-integrin (a collagen receptor and Flnb binding partner) expression was diminished in the mutant growth plate. Like integrin-deficient chondrocytes, adhesion to the ECM was decreased in Flnb(-/-) chondrocytes, and inhibition of beta1-integrin in these cells led to further impairments in cell spreading. These data suggest that disruption of the ECM-beta1-integrin-Flnb pathway contributes to defects in vertebral and distal limb development, similar to those seen in the human autosomal recessive SCT due to Flnb mutations.

The Densovirus of Periplaneta Fuliginosa (PfDNV) As an Insect Vector for Persistent Foreign Gene Expression in Vivo

Biochemical and Biophysical Research Communications. Jul, 2007  |  Pubmed ID: 17517375

An infectious clone of the Periplaneta fuliginosa densovirus (PfDNV) has been constructed and the PfDNV genome can rescue from the plasmid and replicate as the wild-type virus in nymphs of P. fuliginosa. To investigate the ability of the cloned PfDNV genome to be used as a stable and persistent expression vector, we constructed seven recombinant plasmids in which the GFP reporter gene was inserted into the genome of PfDNV. When these recombinant constructs were transfected into hosts, the GFP was expressed efficiently in every clone. Southern blot analysis revealed that recombinant plasmids had integrated into host genome. Infectious recombinant virions could be produced from plasmids in which the GFP gene was downstream of and in frame with the NS3 and NS1 coding regions. These results indicate that PfDNV genome can be used as an insect vector for the transfer and persistent expression of an exogenous gene.

Characterization and Selective Crystallization of Famotidine Polymorphs

Journal of Pharmaceutical Sciences. Sep, 2007  |  Pubmed ID: 17518361

Famotidine crystallizes in two different polymorphic forms: the metastable polymorph B and the stable polymorph A. In this work, solid characterization for both polymorphs has been conducted in detail. The solubility, metastable zone width and interfacial energy of both polymorphs in different solvents have been measured. The influence of solvent, cooling rate, initial concentration and the temperature of nucleation on polymorphism has been investigated. Results show that the nature of polymorph that crystallizes from solution depends on the initial concentration of the solution, solvent, cooling rate, and the temperature of nucleation. Polymorph B preferentially crystallizes only at high concentrations. When acetonitrile or methanol is used as solvent, cooling rate can affect the polymorph of product only at high concentrations. While water is used as solvent, cooling rate has no effect on the polymorph of product, and nucleation temperature is found to be the predominant controlling factor. The effect of crystallization conditions on the polymorph of famotidine can be mainly attributed to the conformational polymorphism. Finally the "polymorphic window" for famotidine crystallized from aqueous solution has been described.

Pharmacokinetics, Tissue Distribution, Metabolism, and Excretion of Depside Salts from Salvia Miltiorrhiza in Rats

Drug Metabolism and Disposition: the Biological Fate of Chemicals. Feb, 2007  |  Pubmed ID: 17132761

Salviae miltiorrhiza, a traditional Chinese medical herb known as "Danshen," has been widely used in clinics to improve blood circulation, relieve blood stasis, and treat coronary heart disease. Depside salts from S. miltiorrhiza are a novel drug in which magnesium lithospermate B and its analogs are the active components. The pharmacokinetics, tissue distribution, metabolism, and excretion of three of the major components, lithospermic acid B, rosmarinic acid (RA), and lithospermic acid (LA), were studied by liquid chromatography-tandem mass spectrometry following intravenous administration in Sprague-Dawley rats. The elimination half-lives for LSB, RA, and LA were 1.04, 0.75, and 2.0 h, respectively, when 60 mg/kg S. miltiorrhiza depside salts were administrated. The areas under the curve for LSB, RA, and LA were 51.6, 6.6, and 25.2 mg . h/l, respectively, and the values decreased in the individual tissues in the following order: kidney > lung > liver > heart > spleen > brain for LSB; kidney > lung > heart > liver > spleen > brain for RA; and heart > lung > kidney > liver > spleen > brain for LA. After intravenous administration of 60 mg/kg S. miltiorrhiza depside salts, 86% of the LSB was excreted in the bile within 6 h. The main metabolites M1 and M2 were found in the serum. Overall, the results show that depside salts from S. miltiorrhiza are rapidly and widely distributed to tissues after intravenous administration in rats but that they are also rapidly cleared and excreted.

Inhibitory Effects of Benzoate on Chiral Inversion and Clearance of N(G)-nitro-arginine in Conscious Rats

Drug Metabolism and Disposition: the Biological Fate of Chemicals. Mar, 2007  |  Pubmed ID: 17172314

N(G)-nitro-arginine (NNA) is known to exhibit stereoselective pharmacokinetics in which N(G)-nitro-d-arginine (d-NNA) has a faster clearance rate than N(G)-nitro-l-arginine (l-NNA) in anesthetized rats, and d-NNA undergoes unidirectional chiral inversion. It was postulated that chiral inversion of d-NNA was performed in a two-step pathway by d-amino acid oxidase (DAAO) followed by an unidentified transaminase. Such chiral inversion contributes (at least partially) to the pharmacokinetic stereoselectivity of NNA. This study used the selective inhibitor of DAAO, sodium benzoate, to test the above hypothesis. An i.v. bolus injection of d-NNA (32 mg/kg) and l-NNA (16 mg/kg) in conscious rats exhibited biphasic disposition with different pharmacokinetic parameters in a stereospecific manner (approximately 5-10-fold differences). Unidirectional chiral inversion of d-NNA but not l-NNA was found from these animals. In addition to its similar inhibitory effects on the d-NNA conversion and DAAO activity in kidney homogenates, sodium benzoate completely blocked chiral inversion of d-NNA and led to a smaller stereospecific difference, reflected by a nearly 50% reduction of d-NNA clearance and a 2-fold increase in t(1/2) and area under the curve of d-NNA in benzoate-pretreated rats. The results suggest that DAAO plays an essential role in chiral inversion of d-NNA and chiral inversion contributes mostly to the pharmacokinetic stereospecificity of NNA.

Reconstituted Expression of Menin in Men1-deficient Mouse Leydig Tumour Cells Induces Cell Cycle Arrest and Apoptosis

European Journal of Cancer (Oxford, England : 1990). Jan, 2007  |  Pubmed ID: 17184987

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary syndrome caused by the inactivation of the responsible gene, MEN1. To date, the lack of MEN1-deficient cell lines derived directly from MEN1 tumours has hampered the detailed study of the MEN1 gene. We have established several stable Men1-deficient Leydig cell tumour (LCT) lines derived from a Leydig cell tumour developed in a male heterozygous Men1 mutant mouse. Our data show that these cell lines maintain the basic characteristics of Leydig cells in terms of both androgen synthesis and gene expression. Interestingly, reconstituted menin expression in one of Men1-deficient LCT cell lines resulted in cell growth inhibition, suggesting that the function of cell growth suppression of the menin pathway, apart from menin itself, is essentially preserved in these cells. Furthermore, we show that menin re-expression in these Men1-deficient cells leads to a block in the transition from G0/G1 to S phase of the cell cycle and an increase in apoptosis, accompanied by a marked increase of p18INK4C and p27Kip1 expression. The current study therefore highlights the importance of menin expression in cell cycle and cell survival control in endocrine cells, and may provide insights into the mechanisms of tumour suppression by menin in related endocrine tumours.

Extremely High Alkaline Protease from a Deep-subsurface Bacterium, Alkaliphilus Transvaalensis

Applied Microbiology and Biotechnology. May, 2007  |  Pubmed ID: 17216443

A new high-alkaline protease (ALTP) was purified to homogeneity from a culture of the strictly anaerobic and extremely alkaliphilic Alkaliphilus transvaalensis. The molecular mass was 30 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme showed the maximal caseinolytic activity higher than pH 12.6 in KCl-NaOH buffer at 40 degrees C. Hydrolysis of the oxidized insulin B-chain followed by mass spectrometric analysis of the cleaved products revealed that as many as 24 of the total 29 peptide bonds are hydrolyzed in a block-cutting manner, suggesting that ALTP has a widespread proteolytic functions. Calcium ion had no effect on the activity and stability of ALTP, unlike known subtilisins. The deduced amino acid sequence of the enzyme comprised 279 amino acids plus 97 prepropeptide amino acids. The amino acid sequence of mature ALTP was confirmed by capillary liquid chromatography coupled to tandem mass spectrometry, which was the 93% coverage of the deduced amino acid sequence. The mature enzyme showed moderate homology to subtilisin LD1 from the alkaliphilic Bacillus sp. strain KSM-LD1 with 64% identity, and both enzymes formed a new subcluster at an intermediate position among true subtilisins and high-alkaline proteases in a phylogenetic tree of subtilase family A. ALTP is the first high-alkaline protease reported from a strict anaerobe in this family.

Application of Direct Crystallization for Racemic Compound Propranolol Hydrochloride

Journal of Pharmaceutical Sciences. Oct, 2007  |  Pubmed ID: 17549769

The application of direct crystallization integrating with chromatography to the resolution of a racemic compound propranolol hydrochloride was studied and the crystallization progression was clearly illustrated in terms of the diagram of solubility and metastable zone widths with different enantiomeric compositions. The solubility and metastable zone widths of propranolol hydrochloride in the mixture of methanol and isopropanol were determined using an in situ Lasentec Focused Beam Reflectance Measurement (FBRM) probe. The direct crystallizations were carried out in an automatic lab reactor (Mettler Toledo LabMax) system. The optical purity of final product crystals was examined using differential scanning calorimetry (DSC), HPLC and PXRD. The crystal size distribution and morphology were analyzed using Malvern Mastersizer and Jeol SEM. It was found that optically pure crystal product could be obtained within certain safe supersaturation limit and there was no evidence of polymorph or solvate/hydrate transformation during the crystallization process. There was no selectivity of crystal growth or nucleation between the pure enantiomer and its racemate when the solution reaches the temperature lower than saturation temperature of the racemate. Hence, the critical supersaturation control of a solution was essential to obtain pure enantiomers from a partially resolved racemate.

Mesoporous Silica Nanoparticles As a Delivery System for Hydrophobic Anticancer Drugs

Small (Weinheim an Der Bergstrasse, Germany). Aug, 2007  |  Pubmed ID: 17566138

GM-CSF Enhances Neural Differentiation of Bone Marrow Stromal Cells

Neuroreport. Jul, 2007  |  Pubmed ID: 17589309

Recent reports suggest that bone marrow stromal cells may be induced into neural cells both in vivo and in vitro. The factors that regulate the neural differentiation and the mechanism involved, however, remains unclear. Here we demonstrated that granulocyte-macrophage colony-stimulating factor (GM-CSF), a potent hematopoietic factor, was able to enhance the neural differentiation of bone marrow stromal cells. Moreover, we found that GM-CSF receptors are abundantly distributed in the bone marrow stromal cells and GM-CSF significantly upregulated the phosphorylation of cAMP-responsive element binding protein in bone marrow stromal cells. These findings suggest that GM-CSF may activate its receptor and then enhance neural differentiation of bone marrow stromal cells by upregulating phosphorylation of cAMP-responsive element binding protein.

Preparation of Monoclonal Antibodies Against Insulin and Their Applications

Hybridoma (2005). Jun, 2007  |  Pubmed ID: 17600501

Monoclonal antibodies (MAbs) against insulin are useful for insulin assays because of their specificity and plentiful supply. We have produced four monoclonal cell strains stably secreting the monoclonal antibodies against insulin; further established subpopulation, titer, affinity; and identified the antibodies as being of subclass IgG(2b)(kappa), one strain, or IgG(1)(kappa), three strains. The smallest detectable level of human insulin by ELISA using this IgG(1) was 1.25 microg/L. The monoclonal antibodies have been used for analyzing insulin content from the sera of type 2 diabetes patients and normal subjects.

Preparation of 99mTc-nitrido Asymmetrical Heterocomplex with 4-(cyclohexylpiperazin-1-yl)-dithioformate and Its Biological Evaluation As a Potential Myocardial Imaging Agent

Applied Radiation and Isotopes : Including Data, Instrumentation and Methods for Use in Agriculture, Industry and Medicine. Oct, 2007  |  Pubmed ID: 17616466

Potassium 4-(cyclohexylpiperazin-1-yl)-dithioformate (HPDTF) was synthesized from 1-cyclohexylpiperazine. The corresponding (99m)Tc-nitrido asymmetrical heterocomplex [(99m)TcN(PNP5)(HPDTF)](+) [PNP5=bis-(dimethoxypropylphosphinoethyl)ethoxyethylamine] was prepared via the [(99m)TcN](int)(2+) precursor in high yields (>95%) and characterized by HPLC and paper electrophoresis. It was found to be lipophilic and cationic, with high stability in vitro. Studies of its biodistribution in mice showed high heart uptake and good myocardial retention ((11.12+/-1.41)% ID/g at 5 min and (10.88+/-1.45)% ID/g at 120 min), as well as rapid clearance from liver, blood and soft tissues. At 60 min post-injection, the heart-to-liver, heart-to-lung and heart-to-blood ratios were 1.30, 3.89 and 27.56, respectively, which suggested that the complex might be suitable for myocardial imaging.

Verification of the Plan Dosimetry for High Dose Rate Brachytherapy Using Metal-oxide-semiconductor Field Effect Transistor Detectors

Medical Physics. Jun, 2007  |  Pubmed ID: 17654904

The feasibility of a recently designed metal-oxide-semiconductor field effect transistor (MOSFET) dosimetry system for dose verification of high dose rate (HDR) brachytherapy treatment planning was investigated. MOSFET detectors were calibrated with a 0.6 cm3 NE-2571 Farmer-type ionization chamber in water. Key characteristics of the MOSFET detectors, such as the energy dependence, that will affect phantom measurements with HDR 192Ir sources were measured. The MOS-FET detector was then applied to verify the dosimetric accuracy of HDR brachytherapy treatments in a custom-made water phantom. Three MOSFET detectors were calibrated independently, with the calibration factors ranging from 0.187 to 0.215 cGy/mV. A distance dependent energy response was observed, significant within 2 cm from the source. The new MOSFET detector has a good reproducibility (<3%), small angular effect (<2%), and good dose linearity (R2=1). It was observed that the MOSFET detectors had a linear response to dose until the threshold voltage reached approximately 24 V for 192Ir source measurements. Further comparison of phantom measurements using MOSFET detectors with dose calculations by a commercial treatment planning system for computed tomography-based brachytherapy treatment plans showed that the mean relative deviation was 2.2 +/- 0.2% for dose points 1 cm away from the source and 2.0 +/- 0.1% for dose points located 2 cm away. The percentage deviations between the measured doses and the planned doses were below 5% for all the measurements. The MOSFET detector, with its advantages of small physical size and ease of use, is a reliable tool for quality assurance of HDR brachytherapy. The phantom verification method described here is universal and can be applied to other HDR brachytherapy treatments.

[In Vitro Transcription Synthesis and Effects of FLT3 Targeted Short Hairpin RNA]

Zhongguo Shi Yan Xue Ye Xue Za Zhi / Zhongguo Bing Li Sheng Li Xue Hui = Journal of Experimental Hematology / Chinese Association of Pathophysiology. Aug, 2007  |  Pubmed ID: 17708815

FMS-like tyrosine kinase 3 (FLT3) is a receptor of tyrosine kinase that is constitutively activated in most of acute myeloid leukemia patients and seems to give an adverse prognosis. In order to explore the silencing effect of FLT3 targeted short hairpin RNA (FLT3-shRNA) on acute leukaemia cell line THP-1, three FLT3-shRNAs (shRNA1, shRNA2, shRNA3) were designed and synthesized by transcription system in vitro and then transfected into THP-1 cells. FLT3 mRNA was analyzed by semi-quantitative RT-PCR, FLT3 protein was detected by Flow cytometry and immunofluorescence. The results indicated that FLT3 expression was downregulated by shRNA1 and shRNA3, and shRNA1 showed stronger inhibitory effect. At 48 hours following transfection, the inhibitory rate of 25 nmol/L shRNA1 was 72.95 +/- 2.07%, lasting 72 hours. The 5 nmol/L and more concentration of FLT3 shRNA1 could downregulate FLT3 mRNA level, which displayed a quantity-effect relation; the inhibitory rate of 15 nmol/L shRNA1 was 67.53 +/- 0.66%. FLT3 protein was located on THP-1 cell membrance, its expression was downregulated obviously by shRNA1, at 72 hours following transfection the inhibitory rate of shRNA1 was 79.67 +/- 0.66%. shRNA1 showed the best inhibitory effect on FLT3 protein, the optimal time of which was 72 hours with an inhibitory rate of 79.67%. It is concluded that FLT3-shRNA1 shows a desireable FLT3-targeted inhibitory effect, which can be used for further investigation of FLT3 mechanism or FLT3 targeting treatment.

[Extracting and Analyzing Rabbit Somatosensory Evoked Potential on the Basis of Continuous Wavelet Transform and Multi-resolution Analysis]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Jun, 2007  |  Pubmed ID: 17713249

This study was directed at extracting the rabbit somatosensory evoked potential (SEP), locating and analyzing the waveform of rabbit SEP. The rabbit was narcotized and stimulated by 0.5 Hz electric pulse. Potential of scalp was sampled at 3.764 Hz. Rabbit somatosensory evoked potential was extracted by one-dimension multi-resolution analysis, and continuous wavelet transform (CWT) was employed to locate and analyze the wave of SEP. The study results showed that Single-trail SEP can be extracted by Daubechies wavelet, when wavelet transform result of single-trail was compared with the result of averaged SEP. Wave component of SEP can be located precisely through the method of continuous wavelet transform. Frequency feature of SEP can also be analyzed by CWT. The technique of continuous wavelet transform, which can project a one-dimension signal into a two-dimension time-frequency space, shows good application prospect of processing medical electronic signal.

Ectropis Obliqua Picorna-like Virus IRES-driven Internal Initiation of Translation in Cell Systems Derived from Different Origins

The Journal of General Virology. Oct, 2007  |  Pubmed ID: 17872537

Ectropis obliqua picorna-like virus (EoPV) is an insect RNA virus that causes a lethal granulosis infection of larvae of the tea looper (Ectropis obliqua). An internal ribosome entry site (IRES) mediates translation initiation of EoPV RNA. Here, bicistronic constructs were used to examine the 5' untranslated region (UTR) of EoPV for IRES activity. The capacities of the EoPV 5' UTR IRES and another insect virus IRES, the cricket paralysis virus intergenic region IRES, to mediate internal translation initiation in a variety of translation systems were also compared. The results demonstrated that the EoPV IRES functioned efficiently not only in mammalian cell-derived systems, but also in an insect cell-derived translation system. However, it functioned inefficiently in a plant cell-derived translation system. This study reveals the host preferences of the EoPV IRES and important differences in IRES function between the EoPV IRES and other characterized picorna-like insect viral IRESs.

[Chaotic Analysis on Cardiac Systems of Normal Pregnant Rats and Fetuses]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Aug, 2007  |  Pubmed ID: 17899770

This investigation was made to explore the chaotic characteristics of cardiac system and differences of autonomic nervous system development of normal pregnant rats and fetuses. The electrocardiograms, chaotic graphics and digital characteristics of heart period signal (HPS) of normal pregnant rats and fetuses by day 21st were evaluated with a computerized HPS extracting and analyzing system. Results: (1) The mean values of frequency and voltage of fetal rats electrocardiograms were lower than those of pregnant rats significantly (P < 0.01). (2) Being similar to those in human, the chaotic graphics showed three-amplitudes spectral features in both normal pregnant rats and fetuses. However, the second amplitude and third amplitude were lower in fetal rats than in pregnant rats. (3) The Heart Relative Dispersion, Lyapunov Exponent and Fractional Dimension were significantly lower in fetal rats than in pregnant rats (P < 0.01). These findings demonstrated that the autonomic nervous system development of fetal rat was still immature and it exhibited lower complexity of HPS and chaotic degree than that of pregnant rat did.

H5N1 Infection of the Respiratory Tract and Beyond: a Molecular Pathology Study

Lancet. Sep, 2007  |  Pubmed ID: 17905166

Human infection with avian influenza H5N1 is an emerging infectious disease characterised by respiratory symptoms and a high fatality rate. Previous studies have shown that the human infection with avian influenza H5N1 could also target organs apart from the lungs.

[Effects of FMS-like Tyrosine Kinase 3 Targeted RNA Interference on Proliferation and Apoptosis of Acute Monocytic Leukemia Cell Line THP-1]

Zhonghua Er Ke Za Zhi. Chinese Journal of Pediatrics. Aug, 2007  |  Pubmed ID: 18021537

FMS-like tyrosine kinase 3 (FLT3) is a receptor tyrosine kinase that is constitutively activated in (70-90)% pediatric patients with acute myeloid leukemia (AML) and appears to confer an adverse prognosis. Although several FLT3-selective small molecule inhibitors and antibodies were developed with varied degrees of success, to address the specificity and resistance, new approaches for specifically targeted FLT3 are needed and RNA interference is a promising choice. The aim of the present study was to investigate the efficacy of suppression of FLT3 induced by small hairpin interfering RNA (shRNA) on myeloproliferation and apoptosis in an acute monocytic leukemia (AMOL) cell line THP-1.

Influence of the Roughness, Topography, and Physicochemical Properties of Chemically Modified Surfaces on the Heterogeneous Nucleation of Protein Crystals

The Journal of Physical Chemistry. B. Dec, 2007  |  Pubmed ID: 18044862

In this study, the influence of some factors on the heterogeneous nucleation of hen egg-white lysozyme (E.C. 3.2.1.17) on a series of chemically modified surfaces has been investigated. Microbatch crystallization experiments were conducted on the microscope glass slides that were treated with poly-L-glutamic acid (PLG), poly(2-hydroxyethyl methacrylate) (P2HEMA), poly(methyl methacrylate) (PMMA), poly(4-vinyl pyridine) (P4VP), and (3-aminopropyl)triethoxysilane (APTES). An optical microscope with a heating/cooling stage was employed to measure the induction time of heterogeneous nucleation. The surface topography and roughness were characterized by atomic force microscopy. Contact angles for crystallization solution on the investigated surfaces were measured by a contact angle meter. From the theoretical analysis, the energetic barrier to heterogeneous nucleation was found to increase at higher contact angles and to decrease at higher roughness. Experimentally, a qualitative increase of the induction time of the heterogeneous nucleation on P2HEMA, APTES, and PMMA surfaces with the contact angle was observed. Such surfaces as P2HEMA, PLG, and APTES, which were of higher roughness, were shown to promote the heterogeneous nucleation. In addition, the surface with specific topography is expected to increase the possibility of the formation of a critical nucleus. Finally, the P4VP surface appeared to suppress the heterogeneous nucleation as a result of the electrostatic interaction between the lysozyme and P4VP molecules.

[A Case Report of Hypertrophic Cardiomyopathy with Noncompaction of Myocardium]

Zhonghua Xin Xue Guan Bing Za Zhi. Sep, 2007  |  Pubmed ID: 18070490

[Change of Heart Rate Power Spectrum and Its Association with Sudden Death in the Fetuses of Rats with Intrahepatic Cholestasis of Pregnancy]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Dec, 2007  |  Pubmed ID: 18232463

To investigate the relationship between imbalance of cardiac autonomic nervous system and sudden death in fetuses of rats with intrahepatic cholestasis of pregnancy (ICP), the animal model of ICP was induced by hypodermic injection of 17-alpha-ethinylestradiol and progesterone. The electrocardiograms and frequency domain analysis of heart rate variability (HRV) including low frequency (LF), high frequency (HF) and the ratio between low and high frequencies (LF/HF) of fetal rats by the 21st day of gestation were evaluated with Chart 5 software of Powerlab biologic signal extracting and analyzing system. RESULTS: (1) The serum total bile acids (TBA) levels of pregnant rats were (78.5 +/- 4.5) micromol/L in Group ICP and (24.6 +/- 3.6) micromol/L in Group control; significant difference was noted between the two groups (P < 0.01). (2) In Group ICP, fetal rats arrhythmias appeared after (29.3 +/- 6.4) minutes' observation, and fetal rats died suddenly after (23.5 +/- 4.6) minutes' arrhythmias; However, the fetal rats in Group control all showed normal electrocardiograms over 90 minutes' continuous observation. (3) The values of LF and LF/HF of fetal rats in Group ICP within 20 minutes before fetal rats arrhythmias were significantly higher than those in Group control (LF 48.45 +/- 4.11 nu vs. 33.87 +/- 4.31 nu, and LF/HF 0.99 +/- 0.14 vs. 0.61 +/- 0.10, respectively, P < 0.01). (4) Dynamic power spectral analysis of HRV indicated that the values of LF and LF/HF of fetal rats in Group ICP increased progressively within 15 minutes before the sudden death of fetal rats. These demonstrated that autonomic imbalance in association with increased sympathetic activity has been strongly implicated in the pathophysiology of fetal arrhythmogenesis and sudden death in ICP. HRV analysis could be a useful tool for fetal surveillance, especially for ICP.

[Treatment of Refractory Rheumatism Among Preschool Children with Autologous Peripheral Blood Hematopoietic Stem Cell Transplantation]

Zhonghua Er Ke Za Zhi. Chinese Journal of Pediatrics. Nov, 2007  |  Pubmed ID: 18282409

To investigate the feasibility and safety of autologous peripheral blood hematopoietic stem cell transplantation (auto-PBHSCT) and its therapeutic effect on refractory rheumatism among preschool children.

[CT and MRI Image Fusion in Three-dimensional Conformal Radiotherapy for Cranial Carcinoma]

Zhonghua Zhong Liu Za Zhi [Chinese Journal of Oncology]. Dec, 2007  |  Pubmed ID: 18478935

To investigate the advantage of CT and MRI image fusion in determining the target precisely during 3-dimensional conformal radiotherapy for cranial carcinoma.

[Analysis of Fatty Acids in Tissues of Spinibarbus Denticulatus Using Ultrasonic Extraction-capillary Gas Chromatography]

Se Pu = Chinese Journal of Chromatography / Zhongguo Hua Xue Hui. Jul, 2007  |  Pubmed ID: 17970136

Mesoporous Silica Nanoparticles for Cancer Therapy: Energy-Dependent Cellular Uptake and Delivery of Paclitaxel to Cancer Cells

Nanobiotechnology : the Journal at the Intersection of Nanotechnology, Molecular Biology, and Biomedical Sciences. May, 2007  |  Pubmed ID: 19936038

Biocompatible mesoporous silica nanoparticles, containing the fluorescence dye fluorescein isothiocyanate (FITC), provide a promising system to deliver hydrophobic anticancer drugs to cancer cells. In this study, we investigated the mechanism of uptake of fluorescent mesoporous silica nanoparticles (FMSN) by cancer cells. Incubation with FMSN at different temperatures showed that the uptake was higher at 37 degrees C than at 4 degrees C. Metabolic inhibitors impeded uptake of FMSN into cells. The inhibition of FMSN uptake by nocodazole treatment suggests that microtubule functions are required. We also report utilization of mesoporous silica nanoparticles to deliver a hydrophobic anticancer drug paclitaxel to PANC-1 cancer cells and to induce inhibition of proliferation. Mesoporous silica nanoparticles may provide a valuable vehicle to deliver hydrophobic anticancer drugs to human cancer cells.

[Experimental Study on Inhibition of Restenosis by Osteopontin Oligopeptide Antagonist After De-endothelium]

Zhongguo Ying Yong Sheng Li Xue Za Zhi = Zhongguo Yingyong Shenglixue Zazhi = Chinese Journal of Applied Physiology. Nov, 2007  |  Pubmed ID: 21180142

Osteopontin 13-peptide(Gly158-Lys170), containing multi-fuction domains was used to inhibit the VSMC adhesion, migration. The mechanism of 13-peptide inhibiting neointima formation was investigated.

3-Amino-1-phenyl-4-(propan-2-yl-idene)pyrazol-5(4H)-one

Acta Crystallographica. Section E, Structure Reports Online. 2007  |  Pubmed ID: 21200961

In the title mol-ecule, C(12)H(13)N(3)O, the phenyl and the pyrazole rings make a dihedral angle of 7.5 (2)°. Inter-molecular N-H⋯O hydrogen bonds involving the amino group link the mol-ecules into a three-dimensional framework.

(E)-2-Meth-oxy-6-[(5-methyl-isoxazol-3-yl)imino-meth-yl]phenol

Acta Crystallographica. Section E, Structure Reports Online. 2008  |  Pubmed ID: 21201520

In the title mol-ecule, C(12)H(12)N(2)O(3), the benzene and isoxazole rings form a dihedral angle of 5.9 (6)°. The hydr-oxy group is involved in an intra-molecular O-H⋯N hydrogen bond [O⋯N = 2.616 (5) Å], resulting in approximate planarity of the mol-ecular skeleton. In the crystal structure, mol-ecules related by translation along the c axis are stacked into columns, the shortest inter-molecular C⋯C distance being 3.298 (6) Å.

[Relationship of Dose-volume Histogram Parameters and Computed Tomography Grading of Radiation-induced Lung Injury in Patients with Non-small Cell Lung Cancer Treated by Three-dimensional Conformal Radiotherapy]

Zhonghua Zhong Liu Za Zhi [Chinese Journal of Oncology]. Sep, 2008  |  Pubmed ID: 19173909

To explore the relationship of dose-volume histogram (DVH) parameters and computed tomography grading of radiation-induced lung injury in patients with non-small cell lung cancer (NSCLC) treated by three-dimensional conformal radiotherapy (3D-CRT).

Multifunctional Inorganic Nanoparticles for Imaging, Targeting, and Drug Delivery

ACS Nano. May, 2008  |  Pubmed ID: 19206485

Drug delivery, magnetic resonance and fluorescence imaging, magnetic manipulation, and cell targeting are simultaneously possible using a multifunctional mesoporous silica nanoparticle. Superparamagnetic iron oxide nanocrystals were encapsulated inside mesostructured silica spheres that were labeled with fluorescent dye molecules and coated with hydrophilic groups to prevent aggregation. Water-insoluble anticancer drugs were delivered into human cancer cells; surface conjugation with cancer-specific targeting agents increased the uptake into cancer cells relative to that in non-cancerous fibroblasts. The highly versatile multifunctional nanoparticles could potentially be used for simultaneous imaging and therapeutic applications.

1H, 13C, and 15N Resonance Assignments of the Reduced and Oxidized Forms of Bacillus Subtilis Thiol Peroxidase

Biomolecular NMR Assignments. Dec, 2008  |  Pubmed ID: 19636900

Bacterial thiol peroxidases (Tpxs) are antioxidant enzymes which exist in various bacteria. Tpxs reduce the lipid hydroperoxides to protect the membrane lipid from destruction by reactive oxygen species. Tpxs are essential enzymes for bacterial anaerobic growth. Herein, we report the resonance assignments of (1)H, (13)C, and (15)N atoms in both the reduced and oxidized forms of Bacillus subtilis Tpx.

Genomic and Functional Profiling of Human Down Syndrome Neural Progenitors Implicates S100B and Aquaporin 4 in Cell Injury

Human Molecular Genetics. Feb, 2008  |  Pubmed ID: 17984171

Down syndrome (DS) is caused by trisomy of chromosome 21 and is characterized by mental retardation, seizures and premature Alzheimer's disease. To examine neuropathological mechanisms giving rise to this disorder, we generated multiple human DS neural progenitor cell (NPC) lines from the 19-21 week frontal cortex and characterized their genomic and functional properties. Microarray profiling of DS progenitors indicated that increased levels of gene expression were not limited to chromosome 21, suggesting that increased expression of genes on chromosome 21 altered transcriptional regulation of a subset of genes throughout the entire genome. Moreover, many transcriptionally dysregulated genes were involved in cell death and oxidative stress. Network analyses suggested that upregulated expression of chromosome 21 genes such as S100B and amyloid precursor protein activated the stress response kinase pathways, and furthermore, could be linked to upregulation of the water channel aquaporin 4 (AQP4). We further demonstrate in DS NPCs that S100B is constitutively overexpressed, that overexpression leads to increased reactive oxygen species (ROS) formation and activation of stress response kinases, and that activation of this pathway results in compensatory AQP4 expression. In addition, AQP4 expression could be induced by direct exposure to ROS, and siRNA inhibition of AQP4 resulted in elevated levels of ROS following S100B exposure. Finally, elevated levels of S100B-induced ROS and loss of AQP4 expression led to increased programmed cell death. These findings suggest that dysregulation of chromosome 21 genes in DS neural progenitors leads to increased ROS and thereby alters transcriptional regulation of cytoprotective, non-chromosome 21 genes in response to ongoing cellular insults.

[The Impact of Antibiotic Treatment in Patients with Influenza-like Illness]

Zhonghua Jie He He Hu Xi Za Zhi = Zhonghua Jiehe He Huxi Zazhi = Chinese Journal of Tuberculosis and Respiratory Diseases. Jul, 2008  |  Pubmed ID: 19035224

To study the etiology of influenza-like illness (ILI) in Beijing, and to investigate the impact of antibiotic treatment on outcomes.

Cherenkov Radiation in Anisotropic Double-negative Metamaterials

Optics Express. Oct, 2008  |  Pubmed ID: 18958126

We theoretically study reversed Cherenkov radiation (CR) in anisotropic double-negative metamaterials (DNMs) in general, and particularly in detail for one of the most practical cases, i.e., CR in a waveguide partially filled with anisotropic DNMs. The theory presented here provides a theoretical basis for possible experiments and potential applications. As an example, we discuss the physical properties of CR and the potential applications such as particle detectors and high-power sources.

Neutrophils May Be a Vehicle for Viral Replication and Dissemination in Human H5N1 Avian Influenza

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America. Dec, 2008  |  Pubmed ID: 18990065

The mechanism of systemic spread of H5N1 virus in patients with avian influenza is unknown. Here, H5N1 nucleoprotein and hemagglutinin were identified by immunohistochemistry in the nucleus and cytoplasm of neutrophils in the placental blood of a pregnant woman. Viral RNA was detected in neutrophils by in situ hybridization and enhanced real-time polymerase chain reaction. Therefore, neutrophils may serve as a vehicle for viral replication and transportation in avian influenza.

Central Administration of Angiotensin-(1-7) Stimulates Nitric Oxide Release and Upregulates the Endothelial Nitric Oxide Synthase Expression Following Focal Cerebral Ischemia/reperfusion in Rats

Neuropeptides. Oct-Dec, 2008  |  Pubmed ID: 18990443

Angiotensin-(1-7) [Ang-(1-7)] is an endogenous peptide of the renin-angiotensin system with several beneficial effects that are often opposite to those attributed to angiotensin II (Ang II). Since there are no data available so far on the role of Ang-(1-7) after cerebral ischemia/reperfusion, in this paper, we investigated the central administration of Ang-(1-7) modulates in vivo the nitric oxide(NO) release and the endothelial NO synthase (eNOS) expression following focal cerebral ischemia/reperfusion in rats. Cerebral ischemia-reperfusion injury was induced by intraluminal thread occlusion of middle cerebral artery in the adult male rats. The levels of NO in ischemic tissues were measured by NO detection kits. Reverse transcription (RT)-PCR and western blot were used to determine messenger RNA (mRNA) and protein levels of the eNOS in ischemic tissues. The cerebral ischemic lesion resulted in a significant increase of NO release at 3 and 6h compared with sham operation group in our model after reperfusion, whereas both medium and high doses Ang-(1-7) markedly enhanced NO levels at 3-24h, and 3-72h after reperfusion, respectively. In addition, NO release increased was significantly induced by high-dose Ang-(1-7) compared with medium-dose Ang-(1-7) at 24-72 h after reperfusion. Medium and high-dose Ang-(1-7) significantly stimulated eNOS activation when compared with artificial cerebrospinal fluid (aCSF) treatment group at 3, 6, 12, 24, and 48h after reperfusion, however, no significant changes in eNOS expression were found between medium and high-dose Ang-(1-7) at different times after the ischemic insult. These findings indicate that medium and high-dose Ang-(1-7) stimulate NO release and upregulate eNOS expression in ischemic tissues following focal cerebral ischemia/reperfusion in rats.

S100B Induces Tau Protein Hyperphosphorylation Via Dickopff-1 Up-regulation and Disrupts the Wnt Pathway in Human Neural Stem Cells

Journal of Cellular and Molecular Medicine. Jun, 2008  |  Pubmed ID: 18494933

Previous studies suggest that levels of the astrocyte-derived S100B protein, such as those occurring in brain extra-cellular spaces consequent to persistent astroglial activation, may have a pathogenetic role in Alzheimer's disease (AD). Although S100B was reported to promote beta amyloid precursor protein overexpression, no clear mechanistic relationship between S100B and formation of neurofibrillary tangles (NFTs) is established. This in vitro study has been aimed at investigating whether S100B is able to disrupt Wnt pathway and lead to tau protein hyperphosphorylation. Utilizing Western blot, electrophoretic mobility shift assay, supershift and reverse transcriptase-polymerase chain reaction techniques, it has been demonstrated that micromolar S100B concentrations stimulate c-Jun N-terminal kinase (JNK) phosphorylation through the receptor for advanced glycation ending products, and subsequently activate nuclear AP-1/cJun transcription, in cultured human neural stem cells. In addition, as revealed by Western blot, small interfering RNA and immunofluorescence analysis, S100B-induced JNK activation increased expression of Dickopff-1 that, in turn, promoted glycogen synthase kinase 3beta phosphorylation and beta-catenin degradation, causing canonical Wnt pathway disruption and tau protein hyperphosphorylation. These findings propose a previously unrecognized link between S100B and tau hyperphosphorylation, suggesting S100B can contribute to NFT formation in AD and in all other conditions in which neuroinflammation may have a crucial role.

Rickettsial Seroepidemiology Among Farm Workers, Tianjin, People's Republic of China

Emerging Infectious Diseases. Jun, 2008  |  Pubmed ID: 18507907

High seroprevalence rates for Anaplasma phagocytophilum (8.8%), Coxiella burnetii (6.4%), Bartonella henselae (9.6%), and Rickettsia typhi (4.1%) in 365 farm workers near Tianjin, People's Republic of China, suggest that human infections with these zoonotic bacteria are frequent and largely unrecognized. Demographic features of seropositive persons suggest distinct epidemiology, ecology, and risks.

Effects of Intracerebroventricular Infusion of Angiotensin-(1-7) on Bradykinin Formation and the Kinin Receptor Expression After Focal Cerebral Ischemia-reperfusion in Rats

Brain Research. Jul, 2008  |  Pubmed ID: 18538311

Accumulating evidence suggests that the angiotensin-(1-7) [Ang-(1-7)], is an active member of the brain renin-angiotensin system (RAS). We evaluated the possibility that intracerebroventricular (ICV, lateral ventricle) infusion of exogenous Ang-(1-7) could participate in the potentiation of bradykinin (BK) release and the kinin receptor expression in ischemic brain parenchyma after focal cerebral ischemia-reperfusion in rats. The middle cerebral artery occlusion (MCAO) and sham-operated models were prepared, continuously administrated with Ang-(1-7) or artificial cerebrospinal fluid (aCSF) by implanted Alzet osmotic minipumps into lateral cerebral ventricle after reperfusion in male Sprague-Dawley (SD) rats. Experimental animals were divided into sham-operated group (sham+aCSF), aCSF treatment group (MCAO+aCSF) and Ang-(1-7) treatment groups [MCAO+Ang-(1-7)] at low (1 pmol/0.5 microl/h), medium (100 pmol/0.5 microl/h) or high (10 nmol/0.5 microl/h) dose levels. Cerebral infarction resulted in a significant increase of BK formation from 3 h to 6 h compared with sham-operated group after reperfusion, whereas medium- and high-dose Ang-(1-7) infusion markedly enhanced BK levels from 6 h to 48 h after reperfusion. Medium- and high-dose Ang-(1-7) infusion markedly increased kinin B(2) receptor mRNA and protein expression, whereas only high-dose Ang-(1-7) infusion induced upregulating the expression of B(1) receptor. Low-dose Ang-(1-7) infusion did not modify both the kinin B(1) and B(2) receptor expression compared with aCSF treatment group after focal cerebral ischemia-reperfusion at each time point. The finding might indicate complex interactions between Ang-(1-7) and kallikrein-kinin system in the CNS after focal cerebral ischemia-reperfusion in rats.

Reversible Conformational Switch Revealed by the Redox Structures of Bacillus Subtilis Thiol Peroxidase

Biochemical and Biophysical Research Communications. Aug, 2008  |  Pubmed ID: 18588855

Bacterial thiol peroxidase (Tpx) is the periplasmic antioxidant enzyme widely distributed in most bacterial species, which catalyzes the reduction of lipid hydroperoxide in vivo. Tpx belongs to the atypical 2-Cys peroxiredoxin (Prx) family and utilizes two active cysteine residues during the redox reaction. Although several crystal structures of Tpx are available, no pair of the redox structures reported thus far. Therefore, the conformational changes coupled to the catalytic reaction remain unclear. Herein, we report the solution structures of Bacillus subtilis Tpx in both the reduced and oxidized forms, the first pair of Tpx structures. The overall structures of both forms are very similar, however, significant differences at the active regions around the C(P) and C(R) residues were observed. In particular, a helix-to-coil transition was observed at the C(R) region between the two forms. Our study reveals a dynamic picture of the conformational switch coupled to the redox reaction, thus provides further insights in understanding the catalytic mechanism of bacterial Tpx.

Effects of Vasoactive Intestinal Peptide on Phenotypic and Functional Maturation of Dendritic Cells

International Immunopharmacology. Oct, 2008  |  Pubmed ID: 18599382

The present study was designed to investigate the effects of vasoactive intestinal peptide (VIP) on differentiation, maturation of dendritic cells (DCs) in vitro. DCs were derived from the murine bone marrow hemopoietic progenitor cells by culturing in RPMI 1640 complete medium supplemented with GM-CSF and IL-4 in the presence or absence of various concentrations of vasoactive intestinal peptide (VIP) and lipopolysaccharide (LPS). The phenotype of DCs was analyzed by flow cytometry. Mixed leukocyte reaction (MLR) was employed to measure the capacity of DC to stimulate the allogeneic T cells. IL-12p70 secretion by DC was examined by ELISA. In the absence of LPS, VIP, in a dose dependent manner, up-regulated the expression of CD80, CD86, CD54 and CD40, but down-regulated the expression of MHC class II molecule (Ia(b)). In the presence of LPS, VIP also dose dependently up-regulated the expression of CD80, CD86, CD54 and CD40, and down-regulated the expression of Ia(b). The capacity to stimulate alloreactive T cells and the production of IL-12p70 by DC were significantly augmented by VIP when compared with VIP-untreated DCs. These data suggest that VIP could promote the phenotypic and functional maturation of DCs, hereby regulating the type and outcome of the conducting immune response.

Bilirubin Possesses Powerful Immunomodulatory Activity and Suppresses Experimental Autoimmune Encephalomyelitis

Journal of Immunology (Baltimore, Md. : 1950). Aug, 2008  |  Pubmed ID: 18641326

Bilirubin, an abundant bile pigment in mammalian serum, was once considered a toxic waste product and has more recently been recognized as a potent antioxidant of physiological importance. However, its potential biological functions in other fields are not well understood. Herein we show that bilirubin is also a powerful immunomodulatory agent. Bilirubin significantly inhibited Ag-specific and polyclonal T cell responses, while other similar antioxidants completely lacked this effect. Bilirubin suppressed CD4(+) T cell responses at multiple steps. High levels of bilirubin could induce apoptosis in reactive CD4(+) T cells. Bilirubin at nonapoptotic concentrations suppressed CD4(+) T cell reactivity through a wide range of actions, including inhibition of costimulator activities, suppression of immune transcription factor activation, and down-regulation of inducible MHC class II expression. Further studies suggest that bilirubin actions were direct, rather than via induction of immune deviation or regulatory T cells. In vivo, treatment with bilirubin effectively suppressed experimental autoimmune encephalomyelitis in SJL/J mice. In contrast, depletion of endogenous bilirubin dramatically exacerbated this disease. In summary, our results identify bilirubin as an important immunomodulator that may protect mammals against autoimmune diseases, thereby indicating its potential in the treatment of multiple sclerosis and other immune disorders.

Toll-like Receptor-4 is Expressed in Meningiomas and Mediates the Antiproliferative Action of Paclitaxel

International Journal of Cancer. Journal International Du Cancer. Oct, 2008  |  Pubmed ID: 18688857

Meningiomas are the second most common type of brain and CNS tumors by histology. Surgery and radiotherapy are main treatment options, but meningiomas may be impossible to adequately resect or may regrow after surgery. In spite of many experimental attempts, there is no generally accepted chemotherapeutic approach. We have studied in a series of meningiomas the expression of the Toll-like receptor 4 (TLR4), which apart from its major role as a key factor of the innate immune system, is believed to play a role in tumorigenesis. All meningiomas studied expressed TLR4 mRNA and protein at variable degree. Paclitaxel, a ligand of TLR4, exhibited a dose- and time-dependent growth suppression in both monolayer and spheroid meningioma cell cultures. The knockdown of TLR4 with siRNA in meningioma cell cultures abrogated the inhibitory effect of paclitaxel. The suppressive action of paclitaxel on meningioma cell growth was enhanced in the presence of fluvastatin or the mitogen-actvated protein kinase (ERK1/2) inhibitor PD98059. At least part of the growth suppressive effect was mediated by the induction of apoptosis in meningioma cells by paclitaxel alone or in combination with fluvastatin. In conclusion, our in vitro results suggest that paclitaxel alone or in combination with other inhibitors of cell growth (statins, MAPK inhibitors) could provide a potential tool for the treatment of TLR4 expressing meningiomas.

[Rest Tension-based Characterization of Isometric Contractility of Bufo Gastrocnemius Ex Vivo]

Nan Fang Yi Ke Da Xue Xue Bao = Journal of Southern Medical University. Aug, 2008  |  Pubmed ID: 18753074

To characterize the isometric contractility of Bufo gastrocnemius ex vivo in light of the rest tension.

[Study on the Target Movement in External-beam Partial Breast Irradiation with Active Breathing Control After Breast-conserving Surgery]

Zhonghua Zhong Liu Za Zhi [Chinese Journal of Oncology]. Mar, 2008  |  Pubmed ID: 18756938

To explore the displacement of surgical clip and cavity during different respiratory status, intrafraction and interfraction for the patients treated by external-beam partial breast irradiation (EB-PBI) assisted by active breathing control (ABC) device after breast-conserving surgery.

[Effects of Ascorbic Acid on Relaxation of Ex Vivo Bufo Gastrocnemius During Sustained Isometric Contraction]

Nan Fang Yi Ke Da Xue Xue Bao = Journal of Southern Medical University. Aug, 2008  |  Pubmed ID: 18819866

To investigate the effect of ascorbic acid (VC) on relaxation of ex vivo Bufo gastrocnemius during sustained isometric contraction.

Notice of Retraction and Apology

Journal of Pharmaceutical Sciences. Apr, 2008  |  Pubmed ID: 18306279

Local Polarity in CO2-expanded Acetonitrile: a Nucleophilic Substitution Reaction and Solvatochromic Probes

The Journal of Organic Chemistry. May, 2008  |  Pubmed ID: 18363361

Many processes that use highly tunable gas-expanded liquids (GXLs) rely on the fact that CO2 addition can greatly affect the polarity of the solvent. We have examined several measures of bulk and local polarity in CO2-expanded acetonitrile to enable more effective exploitation of these polarity changes. The rate of the nucleophilic substitution reaction of tributylamine with methyl p-nitrobenzenesulfonate has been analyzed as a function of solvent composition by using in situ high-pressure UV/vis spectroscopy. We have also measured solvatochromic properties including the Kamlet-Taft pi* parameter and Kosower's Z-value. We correlate these local polarity-based kinetic and solvatochromic measures to develop a better understanding of these property changes as a function of bulk and local solvent composition. The data suggest that local composition enhancement in CO2-expanded acetonitrile has a significant impact on the reaction kinetics.

Light-activated Nanoimpeller-controlled Drug Release in Cancer Cells

Small (Weinheim an Der Bergstrasse, Germany). Apr, 2008  |  Pubmed ID: 18383576

Relaxation-compensated Fast Multislice Amide Proton Transfer (APT) Imaging of Acute Ischemic Stroke

Magnetic Resonance in Medicine : Official Journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine. May, 2008  |  Pubmed ID: 18429031

Amide proton transfer (APT) imaging is a variant form of chemical exchange saturation transfer (CEST) imaging that is based on the magnetization exchange between bulk water and labile endogenous amide protons. Given that chemical exchange is pH-dependent, APT imaging has been shown capable of imaging ischemic tissue acidosis, and as such, may serve as a surrogate metabolic imaging marker complementary to perfusion and diffusion MRI. In order for APT imaging to properly diagnose heterogeneous pathologies such as stroke and cancer, fast volumetric APT imaging has to be developed. In this study the evolution of CEST contrast after RF irradiation was solved showing that although the CEST steady state is reached by the apparent longitudinal relaxation rate, the decreases of CEST contrast after irradiation is governed by the intrinsic relaxation constant. A volumetric APT imaging sequence is proposed that acquires multislice images immediately after a single long continuous wave (CW) RF irradiation, wherein the relaxation-induced loss of CEST contrast is compensated for during postprocessing. The proposed technique was verified by numerical simulation, a tissue-like dual-pH phantom, and demonstrated on an embolic stroke animal model. In summary, our study has established a fast volumetric pH-weighted APT imaging technique, allowing further investigation to fully evaluate its diagnostic power.

Molecular Cloning and Characterization of a Mannose-binding Lectin Gene from Pinellia Cordata

Molecular Biology Reports. Dec, 2008  |  Pubmed ID: 17932788

Using RNA extracted from Pinellia cordata young leaves and primers designed according to the conserved regions of Araceae lectins, the full-length cDNA of Pinellia cordata agglutinin (PCL) was cloned by rapid amplification of cDNA ends (RACE). The full-length cDNA of pcl was 1,182 bp and contained a 768 bp open reading frame (ORF) encoding a lectin precursor of 256 amino acids. Through comparative analysis of pcl gene and its deduced amino acid sequence with those of other Araceae species, it was found that pcl encoded a precursor lectin with signal peptide. PCL is a mannose-binding lectin with three mannose-binding sites. Semi-quantitative RT-PCR analysis revealed that pcl is expressed in all tested tissues including leaf, stem and bulbil, but with the highest expression in bulbil. PCL protein was successfully expressed in Escherichia coli with the molecular weight expected.

Molecular Cloning and Characterization of 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate Reductase Gene from Ginkgo Biloba

Molecular Biology Reports. Sep, 2008  |  Pubmed ID: 17530439

Ginkgo biloba contains terpene triclactones of high pharmaceutical value such as ginkgolides. 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate (HMBPP) reductase (HDR) is proved to be the terminal-acting enzyme in the plastid MEP pathway which provides isoprenoid precursors for the biosynthesis of ginkgolides. The full-length cDNA encoding HDR, designated as GbHDR (Genbank Accession Number DQ364231), was isolated for the first time from G. biloba by RACE method. GbHDR contained a 1,422-bp open reading frame encoding 474 amino acids. The deduced GbHDR protein, showing high identity to HDRs of other plant species, was predicted to possess a chloroplast transit peptide at the N-terminal and four conserved cysteine residues. Two-dimensional structural analysis showed that GbHDR had a similar secondary structure with HDR from Arabidopsis thaliana. Southern blot analysis indicated that GbHDR belonged to a small gene family. Transcription pattern analysis revealed that GbHDR had high transcription in roots, and low in leaves and stems. The cloning of GbHDR gene will enable us to further understand the role of GbHDR involved in terpene triclatones biosynthetic pathway in G. biloba at molecular level.

Histopathologic Findings in Ascending Aortas from Individuals with Loeys-Dietz Syndrome (LDS)

The American Journal of Surgical Pathology. Feb, 2009  |  Pubmed ID: 18852674

Loeys-Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder resulting from genetic mutations in the transforming growth factor beta receptors 1 and 2 (TGFBR1 and TGFBR2). The syndrome is characterized phenotypically by hypertelorism, bifid uvula, and/or cleft palate, and arterial tortuosity with aneurysms and dissections. LDS has a much more rapid clinical course than Marfan syndrome (MFS) and thus those diagnosed with LDS are currently being recommended for prophylactic aortic root replacement at younger ages and with smaller aortic dimensions. Aortic root tissue obtained at surgery was compared between 15 patients carrying a diagnosis of LDS, 11 patients with MFS and 11 control aortas to evaluate the range of histopathologic changes in LDS. Standard hematoxylin and eosin and Movat pentachrome stains were performed. LDS samples had increased medial collagen and a subtle but diffuse form of elastic fiber fragmentation and extracellular matrix deposition, referred to as diffuse medial degeneration. LDS samples had significantly more diffuse medial degeneration compared with MFS and control samples (P<0.05), significantly less medial degeneration of the "cystic" variety compared with MFS (P<0.01) and significantly more collagen deposition than control samples (P<0.01). Additionally, an immunohistochemical stain for pSmad2, a marker of TGFbeta activity, was significantly increased in LDS patients compared with controls (P<0.001). Overall, the histologic findings of LDS are best appreciated with special stains to evaluate fibrosis and elastic fiber fragmentation. The changes described, although not entirely specific for LDS, help differentiate this entity from other vascular diseases in the appropriate clinicopathologic setting.

Tissue Inhibitor of Matrix Metalloproteinase-3 Levels in the Extracellular Matrix of Lung, Kidney, and Eye Increase with Age

The Journal of Histochemistry and Cytochemistry : Official Journal of the Histochemistry Society. Mar, 2009  |  Pubmed ID: 18955737

Tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) is an important regulator of matrix metalloproteinase activity in many types of disease, including atherosclerosis, neoplasia, and inflammatory conditions. Among TIMPs, TIMP-3 uniquely binds the extracellular matrix (ECM). We performed IHC staining on 17 tissue microarrays containing >1500 samples to determine the location of ECM TIMP-3 staining in a variety of predominantly vascular tissues. We found a unique pattern of TIMP-3 staining in the ECM of renal arterioles, small pulmonary vessels and parenchyma, and Bruch's membrane in the retina. There was no staining in larger caliber arteries including coronary and internal mammary arteries. TIMP-3 protein accumulation was found to be an age-dependent phenomenon, with staining appearing in all three tissues in early adulthood and becoming more robust among the elderly. These findings may help to explain the late onset of the TIMP-3-associated ocular diseases Sorsby fundus dystrophy and age-related macular degeneration and suggest a similar phenomenon could be at work in other age-related conditions.

Disruption of Neural Progenitors Along the Ventricular and Subventricular Zones in Periventricular Heterotopia

Human Molecular Genetics. Feb, 2009  |  Pubmed ID: 18996916

Periventricular heterotopia (PH) is a disorder characterized by neuronal nodules, ectopically positioned along the lateral ventricles of the cerebral cortex. Mutations in either of two human genes, Filamin A (FLNA) or ADP-ribosylation factor guanine exchange factor 2 (ARFGEF2), cause PH (Fox et al. in 'Mutations in filamin 1 prevent migration of cerebral cortical neurons in human periventricular heterotopia'. Neuron, 21, 1315-1325, 1998; Sheen et al. in 'Mutations in ARFGEF2 implicate vesicle trafficking in neural progenitor proliferation and migration in the human cerebral cortex'. Nat. Genet., 36, 69-76, 2004). Recent studies have shown that mutations in mitogen-activated protein kinase kinase kinase-4 (Mekk4), an indirect interactor with FlnA, also lead to periventricular nodule formation in mice (Sarkisian et al. in 'MEKK4 signaling regulates filamin expression and neuronal migration'. Neuron, 52, 789-801, 2006). Here we show that neurons in post-mortem human PH brains migrated appropriately into the cortex, that periventricular nodules were primarily composed of later-born neurons, and that the neuroependyma was disrupted in all PH cases. As studied in the mouse, loss of FlnA or Big2 function in neural precursors impaired neuronal migration from the germinal zone, disrupted cell adhesion and compromised neuroepithelial integrity. Finally, the hydrocephalus with hop gait (hyh) mouse, which harbors a mutation in Napa [encoding N-ethylmaleimide-sensitive factor attachment protein alpha (alpha-SNAP)], also develops a progressive denudation of the neuroepithelium, leading to periventricular nodule formation. Previous studies have shown that Arfgef2 and Napa direct vesicle trafficking and fusion, whereas FlnA associates dynamically with the Golgi membranes during budding and trafficking of transport vesicles. Our current findings suggest that PH formation arises from a final common pathway involving disruption of vesicle trafficking, leading to impaired cell adhesion and loss of neuroependymal integrity.

Modularity of the Oncoprotein-like Properties of Platelet Glycoprotein Ibalpha

The Journal of Biological Chemistry. Jan, 2009  |  Pubmed ID: 19017648

Glycoprotein Ib alpha (GpIbalpha), a trans-membrane glycoprotein, is expressed on the surface of megakaryocytes and platelets, where, in association with glycoprotein Ib beta, glycoprotein V, and glycoprotein IX, it normally forms the von Willebrand factor receptor (vWFR). A fully functional vWFR is necessary for platelet attachment, aggregation, and activation and has also been shown to regulate megakaryocyte ploidy. We have recently shown that the gene encoding GpIbalpha is a transcriptional target for the c-Myc oncoprotein and is more widely expressed than previously thought, with particularly high levels occurring in transformed cells. Indeed, GpIbalpha can substitute for c-Myc in promoting growth, transformation, and genomic instability. In the current work, we have demonstrated that, despite the promiscuous expression of GpIbalpha, other vWFR subunits remain largely restricted to megakaryocytes. We have characterized a panel of GpIbalpha mutants and shown that some regions of the protein essential for vWFR activity are not necessary for c-Myc-like functions. Specifically, the six C-terminal amino acids of the cytoplasmic domain, which mediate vWFR signaling, are entirely dispensible for the c-Myc-like functions of GpIbalpha. Instead, these require a more membrane-proximal filamin-binding domain. Also important is the GpIbalpha signal peptide, which, in the absence of other vWFR subunits, directs GpIbalpha to the endoplasmic reticulum rather than the membrane. Together, these results provide strong evidence that the domains of GpIbalpha mediating c-Myc-like functions are modular, genetically distinct, and independent of those involved in vWFR signaling.

Indirubin-3'-monoxime Inhibits Beta-amyloid-induced Neurotoxicity in Neuroblastoma SH-SY5Y Cells

Neuroscience Letters. Jan, 2009  |  Pubmed ID: 19027827

Increasing evidence suggests that the inappropriate activation of cyclin-dependent kinases (CDKs) could induce neuronal apoptosis in Alzheimer's disease (AD), which means that the pharmacological inhibitors of cell-cycle progression may effectively impede the development or progression of AD. Indirubin-3'-monoxime (IMX), a known effective inhibitor of CDKs, has been shown to have therapeutic effects on learning and memory deficits induced by beta-amyloid (Abeta) intracerebroventricular infusion in rats. In the present study, we investigated the neuroprotective effects of IMX on Abeta(25-35)-induced neuronal apoptosis and its potential mechanisms in human neuroblastoma SH-SY5Y cells. Abeta(25-35)-induced apoptosis, characterized by decreased cell viability, neuronal DNA condensation, and fragmentation, was associated with an increase in tau protein hyperphosphorylation. IMX, however, attenuated Abeta(25-35)-induced cell death in a dose-dependent manner. Furthermore, expression of hyperphosphorylation tau protein was significantly decreased with IMX treatment. Our study suggests that IMX may usefully prevent or delay the neuronal loss of AD.

Characterization of Cerebrovascular Responses to Hyperoxia and Hypercapnia Using MRI in Rat

NeuroImage. May, 2009  |  Pubmed ID: 19118633

Understanding cerebrovascular responses to hyperoxia and hypercapnia is important for investigating exogenous regulation of cerebral hemodynamics. We characterized gas-induced vascular changes in the brains of anesthetized healthy rats using magnetic resonance imaging (MRI) while the rats inhaled 100% O(2) (hyperoxia) and 5% CO(2) (hypercapnia). We used echo planar imaging (EPI), arterial spin labeling (ASL), and intravascular superparamagnetic iron oxide nanoparticles (SPION) to quantify vascular responses as measured by blood oxygenation level dependence (BOLD), cerebral blood flow (CBF), cerebral blood volume (CBV), microvascular volume (MVV), and vessel size index (VSI) in multiple brain regions. Hyperoxia resulted in a statistically significant increase in BOLD-weighted MRI signal and significant decrease in CBF and CBV (P<0.05). During hypercapnia, we observed significant increases in BOLD signal, CBF, MVV, and CBV (P<0.05). Despite the regional variability, general trends of vasoconstriction and vasodilation were reflected in VSI changes during O(2) and CO(2) challenges. Interestingly, there was an evident spatial disparity between the O(2) and CO(2) stimuli-induced functional activation maps; that is, cortical and subcortical regions of the brain exhibited notable differences in response to the two gases. Hemodynamic parameters measured in the cortical regions showed greater reactivity to CO(2), whereas these same parameters measured in subcortical regions showed greater responsivity to O(2). Our results demonstrate significant changes of hemodynamic MRI parameters during systemic hypercapnia and hyperoxia in normal cerebral tissue. These gas-dependent changes are spatiotemporally distinctive, suggesting important feasibility for exogenously controlling local cerebral perfusion.

Multiple Neural Networks Supporting a Semantic Task: an FMRI Study Using Independent Component Analysis

NeuroImage. May, 2009  |  Pubmed ID: 19166946

A visual task for semantic access involves a number of brain regions. However, previous studies either examined the role of each region separately using univariate approach, or analyzed a single brain network using covariance connectivity analysis. We hypothesize that these brain regions construct several functional networks underpinning a word semantic access task, these networks being engaged in different cognitive components with distinct temporal characters. In this paper, multivariate independent component analysis (ICA) was used to reveal these networks based on functional magnetic resonance imaging (fMRI) data acquired during a visual and an auditory word semantic judgment task. Our results demonstrated that there were three task-related independent components (ICs), corresponding to various cognitive components involved in the visual task. Furthermore, ICA separation on the auditory task showed consistency of the results with our hypothesis, regardless of the input modalities.

Use of Human Vascular Tissue Microarrays for Measurement of Advanced Glycation Endproducts

The Journal of Histochemistry and Cytochemistry : Official Journal of the Histochemistry Society. Jun, 2009  |  Pubmed ID: 19223295

Advanced glycation endproducts (AGEs) are present in the vasculature and are associated with vascular disease. We determined levels of AGEs in eight distinct adult vascular tissues using tissue microarray (TMA) technology and associated these levels with clinical characteristics. Medium-to-large caliber blood vessels were harvested from 100 adult autopsies to create 17 TMAs. AGE levels were evaluated by IHC using a polyclonal anti-AGE antibody on over 700 unique blood vessels. Slides were digitally scanned, and quantitative analysis was performed using a color deconvolution image analysis technique. Medial AGE staining was strongly correlated between all eight blood vessels. In the media, AGE staining levels were significantly higher at older ages (p=0.009), in white subjects (p<0.001) and with longer postmortem interval (PMI; p<0.0001). These associations remained significant after simultaneous adjustment for age, race/ethnicity, PMI, and diabetes status. Diabetes was associated with elevated AGE levels but only after adjustment for confounding by clinical variables including race/ethnicity, hypertension, and kidney function. This extensive vascular study shows that AGE accumulation in the macrovasculature is a global process affecting atherosclerosis-prone and -resistant vessels. It also suggests ethnicity has a previously undescribed role in vascular tissue AGE levels. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.

Polymorphism and Crystallization of Active Pharmaceutical Ingredients (APIs)

Current Medicinal Chemistry. 2009  |  Pubmed ID: 19275600

Active pharmaceutical ingredients (APIs), frequently delivered to the patient in the solid-state as part of an approved dosage form, can exist in such diverse solid forms as polymorphs, pseudopolymorphs, salts, co-crystals and amorphous solids. Various solid forms often display different mechanical, thermal, physical and chemical properties that can remarkably influence the bioavailability, hygroscopicity, stability and other performance characteristics of the drug. Hence, a thorough understanding of the relationship between the particular solid form of an active pharmaceutical ingredient (API) and its functional properties is important in selecting the most suitable form of the API for development into a drug product. In past decades, there have been significant efforts on the discovery, selection and control of the solid forms of APIs and bulk drugs. This contribution discusses the thermodynamics and kinetics of polymorphic systems, the characterization of polymorphs, and the transformation between polymorphs. The major techniques for polymorph discovery and control developed in the past years are discussed as well.

Transfer of Ephedra Genomic DNA to Yeasts by Ion Implantation

Applied Biochemistry and Biotechnology. Sep, 2009  |  Pubmed ID: 19280123

The genomic DNA from Ephedra glauca was randomly transferred to Saccharomyces cerevisiae and Hansenula anomala by argon and nitrogen ion implantation. Through repeated subculturing and using reversed phase high-performance liquid chromatography analysis to quantify the concentrations of the secondary metabolites, l-ephedrine and d-pseudoephedrine, 12 recombinant strains of genetically stable yeast were obtained, each using glucose as a carbon source, NaNO3 as a nitrogen source and producing l-ephedrine and/or d-pseudoephedrine. After culturing in liquid medium for 72 h, extracellular l-ephedrine and d-pseudoephedrine concentrations of 18.85 and 4.11 mg/L, respectively, were detected. Using l-ephedrine and d-pseudoephedrine as the target products, the transformation efficiencies of the genomic DNA from E. glauca transferred to S. cerevisiae and H. anomala were 1.15% (1/87) and 2.13% (8/376), respectively. The addition of the amino acid, L-Phe, to culture media substantially changed the amount of l-ephedrine and/or d-pseudoephedrine produced by the recombined yeasts. However, the change in metabolite production was not consistent among strains, rising in some, while dropping to nondetectable levels in others. After random amplification of polymorphic DNA (RAPD) analysis, four RAPD primers were obtained from the initial 100 RAPD primers, each amplifying different fragments with the recombined yeast Ar_Han0458 genome. Using one primer as polymerase chain reaction primer, the result showed that the recombined yeast Ar_Han0458 genome matched E. glauca genomic DNA at 150 bp, indicating a successful transfer of genetic information, facilitated by ion implantation.

Solution Structure of the Escherichia Coli HybE Reveals a Novel Fold

Proteins. Jun, 2009  |  Pubmed ID: 19291739

Protection of Lung Function by Introducing Single Photon Emission Computed Tomography Lung Perfusion Image into Radiotherapy Plan of Lung Cancer

Chinese Medical Journal. Mar, 2009  |  Pubmed ID: 19323899

The lung functional status could be displayed on lung perfusion images. With the images, the radiotherapy plans of lung cancer could be guided to more optimized. This study aimed to assess quantitatively the impact of incorporating functional lung imaging into 3-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiation therapy (IMRT) planning for non-small cell lung cancer (NSCLC).

Solution Structure of Apo-YjaB from Escherichia Coli

Proteins. Jul, 2009  |  Pubmed ID: 19343803

In Vivo Antitumor Effect of a Novel Inhibitor of Protein Geranylgeranyltransferase-I

Molecular Cancer Therapeutics. May, 2009  |  Pubmed ID: 19417142

Protein geranylgeranyltransferase-I (GGTase-I) catalyzes protein geranylgeranylation, which is critical for the function of proteins such as Rho, Rac, and Ral. We previously identified several small-molecule inhibitors of GGTase-I from an allenoate-derived compound library and showed that these compounds exhibit specific inhibition of GGTase-I resulting in the inhibition of proliferation associated with the induction of G(1) cell cycle arrest of a variety of cancer cell lines. Because inhibition of GGTase-I is expected to suppress tumor growth, we investigated in vivo effects of one of these GGTase-I inhibitors (GGTI), P61A6, by using a human pancreatic cancer xenograft model in mice. The new compound GGTI P61A6 showed an excellent antitumor effect. I.p. administration of P61A6 significantly suppressed tumor growth of the PANC-1 xenograft. Even once per week administration of GGTI was enough to suppress tumor growth. Immunohistochemical examination indicated the inhibition of cell proliferation in the tumors by P61A6 treatment, but neither apoptosis nor antiangiogenesis was observed. Increased cytosolic localization of proteins such as Rap1 and RhoA in tumors was observed. In addition, the enzyme activity of GGTase-I in tumors was inhibited. Pharmacokinetic analysis showed that the plasma half-life of GGTI is ∼6 h, suggesting its prolonged effect. These data suggest that the novel GGTI compound P61A6 is an excellent chemotherapeutic drug candidate for human pancreatic cancer. They also provide evidence that protein GGTase-I may be a valid target for cancer therapy.

Latency-associated Nuclear Antigen of Kaposi's Sarcoma-associated Herpesvirus (KSHV) Upregulates Survivin Expression in KSHV-Associated B-lymphoma Cells and Contributes to Their Proliferation

Journal of Virology. Jul, 2009  |  Pubmed ID: 19439469

Survivin is a master regulator of cell proliferation and cell viability and is highly expressed in most human tumors. The molecular network linked to survivin expression in tumors has not been completely elucidated. In this study, we show that latency-associated nuclear antigen (LANA), a multifunctional protein of Kaposi's sarcoma-associated herpesvirus (KSHV) that is found in Kaposi's sarcoma tumors, upregulates survivin expression and increases the proliferation of KSHV-infected B cells. Analysis of pathway-specific gene arrays showed that survivin expression was highly upregulated in BJAB cells expressing LANA. The mRNA levels of survivin were also upregulated in HEK 293 and BJAB cells expressing LANA. Similarly, protein levels of survivin were significantly higher in LANA-expressing, as well as KSHV-infected, cells. Survivin promoter activity assays identified GC/Sp1 and p53 cis-acting elements within the core promoter region as being important for LANA activity. Gel mobility shift assays revealed that LANA forms a complex with Sp1 or Sp1-like proteins bound to the GC/Sp1 box of the survivin promoter. In addition, a LANA/p53 complex bound to the p53 cis-acting element within the survivin promoter, indicating that upregulation of survivin expression can also occur through suppression of p53 function. Furthermore, immunohistochemistry analyses revealed that survivin expression was upregulated in KSHV-associated Kaposi's sarcoma tissue, suggesting that LANA plays an important role in the upregulation of survivin expression in KSHV-infected endothelial cells. Knockdown of survivin expression by lentivirus-delivered small hairpin RNA resulted in loss of cell proliferation in KSHV-infected cells. Therefore, upregulation of survivin expression in KSHV-associated human cells contributes to their proliferation.

Prevalence and Risk Factors for Type 2 Diabetes Mellitus in the Chinese Adult Population: the InterASIA Study

Diabetes Research and Clinical Practice. Jun, 2009  |  Pubmed ID: 19442859

To estimate the prevalence of impaired fasting glucose and type 2 diabetes mellitus (T2DM) and identify the potential risk factors of T2DM in Chinese adults.

Vagus Nerve Stimulation Reduces Infarct Size in Rat Focal Cerebral Ischemia

Neuroscience Letters. Aug, 2009  |  Pubmed ID: 19446004

Background and purpose: We sought to determine the effect of vagus nerve stimulation (VNS) on infarct size after transient focal cerebral ischemia in rats. Methods: Ischemia was produced by transient filament occlusion of the right middle cerebral artery. Stimulating electrodes were implanted on the cervical part of the right vagus nerve. Electrical stimulation was initiated 30 min after the induction of ischemia, and delivered for 30s at every 30 min for 3h in experimental group 1 and at every 5 min for 1h in experimental group 2. All the procedures were duplicated but no stimulus was delivered in the control group. Functional deficit was evaluated and animals were killed to determine the infarct size 24h after ischemia. Results: Ischemic lesion volume was smaller in VNS-treated animals as compared with control animals; the relative percentage of contralateral hemispheric volume that underwent infarction was 16.2+/-3.2% in the VNS and 33.0+/-5.0% in the control arms in experimental group 1 (p<0.05). The respective values for experimental group 2 were 19.8+/-0.5% and 37.9+/-2.6% (p<0.05). VNS-treated animals were significantly more likely to have better functional scores at 24h as compared with control animals. The functional score improved by 50% in experimental group 1 and 44% in experimental group 2 (p<0.05 for both groups). Conclusion: VNS appears to offer protection against acute ischemic brain injury.

Excess Zn Alters the Nutrient Uptake and Induces the Antioxidative Responses in Submerged Plant Hydrilla Verticillata (L.f.) Royle

Chemosphere. Aug, 2009  |  Pubmed ID: 19487013

To investigate the effects of zinc (Zn) on aquatic macrophyte, the submerged plant Hydrilla verticillata (L.f.) Royle was cultured in control solution or together with 0.05-30 mg L(-1) Zn(2+) for 7 d. The alterations in nutrient uptake and antioxidative response were assayed. Zn stress increased the uptake of Cu, Fe, Mn, Mg, and Zn while decreased that of P. Compared with control plants, the synthesis of chlorophyll was stimulated at 0.05-0.5 mg L(-1) Zn but inhibited at concentrations >5 mg L(-1), while the activity of NADH oxidase was suppressed at low level of Zn(2+) (0.05-5 mg L(-1)) but activated at concentrations of 30 mg L(-1). There were not significant changes in the content of malondialdehyde and activity of lipoxygenase, catalase, and glutathione S-transferase in the presence of Zn concentrations up to 0.5 mg L(-1) Zn, while at high concentrations significant increase in these parameters was observed. Meanwhile, activity of total superoxide dismutase increased in all treatments compared with control plants. The activity of guaiacol peroxidase and ascorbate peroxidase increased at 0.5-30 mg L(-1) Zn, and that of glutathione reductase increased at concentration of 0.05-0.5 mg L(-1) Zn but decreased significantly at 5-30 mg L(-1). In addition, some important antioxidative metabolites such as ascorbate, dehydroascorbate, glutathione and oxidized glutathione increased significantly in leaves treated with 10-30 mg L(-1) Zn when compared with control plants. These results suggested that Zn induced the nutrient imbalance and oxidative damage and the accelerated operation of antioxidative reactions might provide H. verticillata (L.f.) Royle with the enhanced Zn-stress tolerance.

Glomerular Protein Levels of Matrix Metalloproteinase-1 and Tissue Inhibitor of Metalloproteinase-1 Are Lower in Diabetic Subjects

The Journal of Histochemistry and Cytochemistry : Official Journal of the Histochemistry Society. Nov, 2009  |  Pubmed ID: 19506087

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix turnover throughout the body, including in renal glomeruli. We investigated protein levels of multiple MMPs (MMP-1, MMP-2, MMP-3, and MMP-9) and TIMP-1 in glomeruli and investigated whether disease phenotypes were associated with levels of these proteins. Renal cortex was collected from 100 adult autopsy subjects arrayed across 17 tissue microarrays. Immunohistochemical staining intensity for each MMP and TIMP-1 was determined using quantitative color deconvolution techniques. We observed significantly decreased glomerular MMP-1 and TIMP-1 staining in subjects with diabetes, hypertension, and an estimated glomerular filtration rate <30 ml/min/1.73 m(2) in univariate analyses. MMP-1 staining, but not TIMP-1 staining, was inversely correlated with increased glomerular fibrosis (r = -0.40). In multivariable analysis, diabetes was robustly associated with decreased staining intensity. This study indicates that in human subjects, the long-term sequelae of diseases such as diabetes that cause chronic renal failure result in decreased TIMP-1 and MMP-1 proteins in renal glomeruli. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.

Inhibition of Serine/threonine Phosphatase PP2A Enhances Cancer Chemotherapy by Blocking DNA Damage Induced Defense Mechanisms

Proceedings of the National Academy of Sciences of the United States of America. Jul, 2009  |  Pubmed ID: 19564615

A variety of mechanisms maintain the integrity of the genome in the face of cell stress. Cancer cell response to chemotherapeutic and radiation-induced DNA damage is mediated by multiple defense mechanisms including polo-like kinase 1 (Plk-1), protein kinase B (Akt-1), and/or p53 pathways leading to either apoptosis or cell cycle arrest. Subsequently, a subpopulation of arrested viable cancer cells may remain and recur despite aggressive and repetitive therapy. Here, we show that modulation (activation of Akt-1 and Plk-1 and repression of p53) of these pathways simultaneously results in paradoxical enhancement of the effectiveness of cytotoxic chemotherapy. We demonstrate that a small molecule inhibitor, LB-1.2, of protein phosphatase 2A (PP2A) activates Plk-1 and Akt-1 and decreases p53 abundance in tumor cells. Combined with temozolomide (TMZ; a DNA-methylating chemotherapeutic drug), LB-1.2 causes complete regression of glioblastoma multiforme (GBM) xenografts without recurrence in 50% of animals (up to 28 weeks) and complete inhibition of growth of neuroblastoma (NB) xenografts. Treatment with either drug alone results in only short-term inhibition/regression with all xenografts resuming rapid growth. Combined with another widely used anticancer drug, Doxorubicin (DOX, a DNA intercalating agent), LB-1.2 also causes marked GBM xenograft regression, whereas DOX alone only slows growth. Inhibition of PP2A by LB-1.2 blocks cell-cycle arrest and increases progression of cell cycle in the presence of TMZ or DOX. Pharmacologic inhibition of PP2A may be a general method for enhancing the effectiveness of cancer treatments that damage DNA or disrupt components of cell replication.

[18F]2-fluoro-2-deoxyglucose Positron Emission Tomography/computed Tomography in Predicting Radiation Pneumonitis

Chinese Medical Journal. Jun, 2009  |  Pubmed ID: 19567143

Prevention is presently the only available method to limit radiation-induced lung morbidity. A good predictor is the key point of prevention. This study aimed to investigate if [(18)F]2-fluoro-2-deoxyglucose (FDG) uptake changes in the lung after radiotherapy could be used as a new predictor for acute radiation pneumonitis (RP).

Combination Therapy with Normobaric Oxygen (NBO) Plus Thrombolysis in Experimental Ischemic Stroke

BMC Neuroscience. 2009  |  Pubmed ID: 19604385

The widespread use of tissue plasminogen activator (tPA), the only FDA-approved acute stroke treatment, remains limited by its narrow therapeutic time window and related risks of brain hemorrhage. Normobaric oxygen therapy (NBO) may be a useful physiological strategy that slows down the process of cerebral infarction, thus potentially allowing for delayed or more effective thrombolysis. In this study we investigated the effects of NBO started simultaneously with intravenous tPA, in spontaneously hypertensive rats subjected to embolic middle cerebral artery (MCA) stroke. After homologous clot injection, animals were randomized into different treatment groups: saline injected at 1 hour; tPA at 1 hour; saline at 1 hour plus NBO; tPA at 1 hour plus NBO. NBO was maintained for 3 hours. Infarct volume, brain swelling and hemorrhagic transformation were quantified at 24 hours. Outcome assessments were blinded to therapy.

Study on Migration of Melamine from Food Packaging Materials on Markets

Biomedical and Environmental Sciences : BES. Apr, 2009  |  Pubmed ID: 19618686

To study the migration of melamine into foods from plastic food packaging materials and dairy product containers commonly used in China.

1H, 13C and 15N Resonance Assignments of the Chaperone HybE of Hydrogenase-2 from Escherichia Coli

Biomolecular NMR Assignments. Jun, 2009  |  Pubmed ID: 19636963

Escherichia coli HybE is a chaperone of hydrogenase-2 and plays a critical role in coordinating the assembly and export of the HybO and HybC subunits of hydrogenase-2. Previous studies indicated that the quality-control during the assembly and export of the HybO-HybC by the Tat pathway was putatively performed by HybE. However, the molecular basis of the biological function of HybE remains unknown. The structural information is essential in order to obtain functional insights of HybE. Here we report the backbone and sidechain resonance assignments of (1)H, (13)C and (15) N atoms in E. coli HybE.

The Type III Secretion System is Involved in the Invasion and Intracellular Survival of Escherichia Coli K1 in Human Brain Microvascular Endothelial Cells

FEMS Microbiology Letters. Nov, 2009  |  Pubmed ID: 19758329

Type III secretion systems (T3SSs) have been documented in many Gram-negative bacteria, including enterohemorrhagic Escherichia coli. We have previously shown the existence of a putative T3SS in meningitis-causing E. coli K1 strains, referred to as E. coli type III secretion 2 (ETT2). The sequence of ETT2 in meningitis-causing E. coli K1 strain EC10 (O7:K1) revealed that ETT2 comprises the epr, epa and eiv genes, but bears mutations, deletions and insertions. We constructed the EC10 mutants deleted of ETT2 or eivA gene, and their contributions to bacterial pathogenesis were evaluated in human brain microvascular endothelial cells (HBMECs). The deletion mutant of ETT2 exhibited defects in invasion and intracellular survival compared with the parental E. coli K1 strain EC10. The mutant deleted of eivA within ETT2 was also significantly defective in invasion and intracellular survival in HBMECs, and the defects of the eiv mutant were restored to the levels of the parent strain EC10 by transcomplementation. These findings suggest that ETT2 plays a role in the pathogenesis of E. coli K1 infection, including meningitis.

[Progress in Functional Polyphosphate in Prokaryotic and Eukaryotic Living Organisms]

Sheng Li Ke Xue Jin Zhan [Progress in Physiology]. Jul, 2009  |  Pubmed ID: 19803421

Polyphosphate (poly P) has been widely identified in both inorganic environment and living organisms. Research shows that poly P in bacteria enhances their resistance to severe environment, triggers their protective responses, increases biofilm formation and involves in predation and bacterial virulence. In eukaryotes, poly P has been found to enhance the proliferation of fibroblast and many tumor cell lines, induce the calcification of osteoblast and be involved in calcium ion release. Based on the existing information, we attempt to discuss the possible functions of poly P in the nervous system.

Small RNAs Serve As a Genetic Buffer Against Genomic Shock in Arabidopsis Interspecific Hybrids and Allopolyploids

Proceedings of the National Academy of Sciences of the United States of America. Oct, 2009  |  Pubmed ID: 19805056

Small RNAs, including microRNAs (miRNAs), small interfering RNAs (siRNAs), and trans-acting siRNAs (tasiRNAs), control gene expression and epigenetic regulation. Although the roles of miRNAs and siRNAs have been extensively studied, their expression diversity and evolution in closely related species and interspecific hybrids are poorly understood. Here, we show comprehensive analyses of miRNA expression and siRNA distributions in two closely related species Arabidopsis thaliana and Arabidopsis arenosa, a natural allotetraploid Arabidopsis suecica, and two resynthesized allotetraploid lines (F(1) and F(7)) derived from A. thaliana and A. arenosa. We found that repeat- and transposon-associated siRNAs were highly divergent between A. thaliana and A. arenosa. A. thaliana siRNA populations underwent rapid changes in F(1) but were stably maintained in F(7) and A. suecica. The correlation between siRNAs and nonadditive gene expression in allopolyploids is insignificant. In contrast, miRNA and tasiRNA sequences were conserved between species, but their expression patterns were highly variable between the allotetraploids and their progenitors. Many miRNAs tested were nonadditively expressed (deviating from the mid-parent value, MPV) in the allotetraploids and triggered unequal degradation of A. thaliana or A. arenosa targets. The data suggest that small RNAs produced during interspecific hybridization or polyploidization serve as a buffer against the genomic shock in interspecific hybrids and allopolyploids: Stable inheritance of repeat-associated siRNAs maintains chromatin and genome stability, whereas expression variation of miRNAs leads to changes in gene expression, growth vigor, and adaptation.

Enhancement of Cancer Chemotherapy by Simultaneously Altering Cell Cycle Progression and DNA-damage Defenses Through Global Modification of the Serine/threonine Phospho-proteome

Cell Cycle (Georgetown, Tex.). Oct, 2009  |  Pubmed ID: 19806030

Despite improvements in the therapeutic efficacy of rationally designed cancer treatment regimens, most cancers remain incurable once spread beyond their sites of origin. Failure to achieve sustained control or eradication of cancers arises in large part because a subpopulation of quiescent "cancer stem cells" is insensitive to drugs targeting cell growth and replication and because defense mechanisms critical to survival of the normal cell also protect the cancer cell from cytotoxic injury. Global alteration of signal transduction by inhibition of serine/threonine dephosphorylation has recently been shown to markedly potentiate cancer cell killing by the DNA-methylating drug, temozolomide. Inhibition of the multifunctional protein phosphatase 2A appears to drive quiescent cancer cells into cycle and simultaneously inhibits cycle arrest, permitting cancer cell entry into mitosis despite the presence of chemotherapy induced DNA-damage. Absence of toxicity in animal models suggests that multi-site mutations in pathways regulating cell cycle in cancer cells make them more vulnerable than normal cells to large changes in the balance of phosphorylation-regulated signaling. Global modulation of the serine-threonine phospho-proteome may be a general method for enhancing the effectiveness of cytotoxic cancer therapy.

Role of NMDA Receptor-dependent Activation of SREBP1 in Excitotoxic and Ischemic Neuronal Injuries

Nature Medicine. Dec, 2009  |  Pubmed ID: 19966780

Excitotoxic neuronal damage caused by overactivation of N-methyl-D-aspartate glutamate receptors (NMDARs) is thought to be a principal cause of neuronal loss after stroke and brain trauma. Here we report that activation of sterol regulatory element binding protein-1 (SREBP-1) transcription factor in affected neurons is an essential step in NMDAR-mediated excitotoxic neuronal death in both in vitro and in vivo models of stroke. The NMDAR-mediated activation of SREBP-1 is a result of increased insulin-induced gene-1 (Insig-1) degradation, which can be inhibited with an Insig-1-derived interference peptide (Indip) that we have developed. Using a focal ischemia model of stroke, we show that systemic administration of Indip not only prevents SREBP-1 activation but also substantially reduces neuronal damage and improves behavioral outcome. Our study suggests that agents that reduce SREBP-1 activation such as Indip may represent a new class of neuroprotective therapeutics against stroke.

[Influence of Active Breathing Control on the Dose Distribution in the Target of Forward Whole-breast Intensity-modulated Radiotherapy After Breast Conserving Surgery]

Zhonghua Zhong Liu Za Zhi [Chinese Journal of Oncology]. Aug, 2009  |  Pubmed ID: 20021951

To explore the influence of intrafraction and interfraction target displacement on the dose distribution in the target of forward whole-breast intensity-modulated radiotherapy (IMRT) assisted by active breathing control (ABC).

[Effect of Substance P on Cardiac Autonomic Nervous Function in Rats]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Dec, 2009  |  Pubmed ID: 20095495

Forty SD rats were divided into 5 groups: control group, SP groups (5 microg/kg,10 microg/kg, 20 microg/kg) and spantide II plus SP group. An analysis of heart rate variability (HRV) was used to detect the changes of HRV parameters before and after intravenous injection of SP in order to investigate the effect of substance P on cardiac autonomic nervous function and the corresponding mechanism. Results: (1) There were significant differences in most HRV parameters for the three different doses of SP. Mean heart period (MHP), absolute power of ultra-low frequency and high frequency band (APU, APH), total power (TPV) and ratio of power in ultra-low to high frequency band (RUH) increased, while mean heart rate (MHR) and chaos intensity (HCC) decreased during the 30 minutes. Each peak amplitude of HRV parameters went higher and showed up ahead of the upward doses of SP. (2) Significant change was seen in each of the parameters between spantide II plus SP group and high-dose SP group. These data idicate that, after intravenous injection of different doses of SP, both cardiac sympathetic nervous system activity and parasympathetic nervous system activity increase, and the function of cardiac autonomic nervous becomes instable and unbalanced. The effect of SP may be dose dependent, and it is possibly mediated by neurokinin-1(NK-1) receptor.

Perilipin Gene 1237 T > C Polymorphism is Not Associated with Obesity Risk in Northern Chinese Han Adults

Biomedical and Environmental Sciences : BES. Oct, 2009  |  Pubmed ID: 20163070

To identify the association between PLIN 1237 polymorphism and obesity in Chinese Han adults.

Silica Nanoparticles As a Delivery System for Nucleic Acid-based Reagents

Journal of Materials Chemistry. Jan, 2009  |  Pubmed ID: 20740060

The transport of nucleic acid-based reagents is predicated upon developing structurally stable delivery systems that can preferentially bind and protect DNA and RNA, and release their cargo upon reaching their designated sites. Recent advancements in tailoring the size, shape, and external surface functionalization of silica materials have led to increased biocompatibility and efficiency of delivery. In this Feature Article, we highlight recent research progress in the use of silica nanoparticles as a delivery vehicle for nucleic acid-based reagents.

(E,E)-2,5-Bis(5-chloro-2-methoxyphenyl)-3,4-diazahexa-2,4-diene

Acta Crystallographica. Section E, Structure Reports Online. 2009  |  Pubmed ID: 21578897

The title compound, C(18)H(18)Cl(2)N(2)O(2), was synthesized by the reaction of 1-(5-chloro-2-methoxy-phen-yl)ethanone with hydrazine hydrate. The mol-ecule lies on a crystallographic twofold axis passing through the mid-point of the N-N bond with one half-mol-ecule in the asymmetric unit. The dihedral angle between the two aromatic rings is 44.33 (4)°. In the crystal, inter-molecular C-H⋯O inter-actions link the mol-ecules into columns along the c axis.

N'-[(1E)-1-(5-Chloro-2-hydroxy-phen-yl)propyl-idene]-4-methoxy-benzohydrazide

Acta Crystallographica. Section E, Structure Reports Online. 2009  |  Pubmed ID: 21580032

The title compound, C(17)H(17)ClN(2)O(3), has a trans conformation about the C=N double bond and an intra-molecular O-H⋯N occurs. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds.

Aqua-bis(2-iodo-acetato-κO)(1,10-phenanthroline-κN,N')copper(II)

Acta Crystallographica. Section E, Structure Reports Online. 2009  |  Pubmed ID: 21581830

In the title compound, [Cu(C(2)H(2)IO(2))(2)(C(12)H(8)N(2))(H(2)O)], the Cu(II) ion is coordinated by two N atoms [Cu-N = 2.013 (4) and 2.024 (4) Å] from a 1,10-phenanthroline ligand and three O atoms [Cu-O = 1.940 (4)-2.261 (4) Å] from two carboxyl ligands and a water mol-ecule in a distorted square-pyramidal geometry. One iodo-acetate O atom [Cu-O = 2.775 (4) Å] completes the coordination to form a distorted octa-hedron. Inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into centrosymmetric dimers, which are further packed by π-π inter-actions between the 1,10-phenanthroline ligands into layers parallel to the ab plane. The crystal packing also exhibits short inter-molecular I⋯I contacts of 3.6772 (9) Å and weak C-H⋯O hydrogen bonds.

[Comparison of Overlap Ratios of the Target Volume in Different Respiratory States with Active Breathing Control for External-beam Partial Breast Irradiation]

Zhonghua Zhong Liu Za Zhi [Chinese Journal of Oncology]. Dec, 2010  |  Pubmed ID: 21223802

To explore the overlap ratio of the target volume in different respiratory statuses of active breath control (ABC) and their differences during external-beam partial breast irradiation (EB-PBI), and from the perspective of target volume overlap to determine the influence of the ABC-assisted breathing condition on intra-fractional target movement of EB-PBI.

[Effects of Human Bone Marrow Mesenchymal Stem Cells on Cytokines Secretion from Allogeneic Dendritic Cell Activated Cytokine-induced Killer Cells]

Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi = Chinese Journal of Cellular and Molecular Immunology. Oct, 2010  |  Pubmed ID: 20937236

to study the effect of human bone marrow derived mesenchymal stem cells (hMSCs) on cytokines secretion (IFN-γ, TNF-α, IL-10, IL-6, IL-4 and IL-2) of allogeneic DC-CIK cells (in co-culture of CIK cells with DC), which investigate the mechanism of immunoregulation induced by hMSCs.

Molecular Biology of Kaposi's Sarcoma-associated Herpesvirus and Related Oncogenesis

Advances in Virus Research. 2010  |  Pubmed ID: 21040832

Kaposi's Sarcoma-associated Herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8), is the most recently identified human tumor virus,and is associated with the pathogenesis of Kaposi's sarcoma and two lymphoproliferative disorders known to occur frequently in AIDS patients-primary effusion lymphoma and multicentric Castleman disease. In the 15 years since its discovery, intense studies have demonstrated an etiologic role for KSHV in the development of these malignancies. Here, we review the recent advances linked to understanding KSHV latent and lytic life cycle and the molecular mechanisms of KSHV-mediated oncogenesis in terms of transformation, cell signaling, cell growth and survival, angiogenesis, immune invasion and response to microenvironmental stress, and highlight the potential therapeutic targets for blocking KSHV tumorigenesis.

Decreased Glucocerebrosidase Activity in Gaucher Disease Parallels Quantitative Enzyme Loss Due to Abnormal Interaction with TCP1 and C-Cbl

Proceedings of the National Academy of Sciences of the United States of America. Dec, 2010  |  Pubmed ID: 21098288

Gaucher disease (GD), the most common lysosomal storage disorder of humans, is caused by mutations in the gene coding for the enzyme glucocerebrosidase (GCase). Clinical manifestations vary among patients with the three types of GD, and phenotypic heterogeneity occurs even among patients with identical mutations. To gain insight into why phenotypic heterogeneity occurs in GD, we investigated mechanisms underlying the net loss of GCase catalytic activity in cultured skin fibroblasts derived from patients with the three types of GD. The findings indicate that the loss of catalytic activity of GCase correlates with its quantitative reduction, rather than a decrease in functional capacity of mutant enzyme. Use of a proteasome inhibitor, lactacystin, resulted in increased expression of GCase, suggesting a mechanism of protein degradation in GD. Furthermore, reduced binding of GCase to TCP1 ring complex (TRiC), a regulator of correct protein folding, may result in defective maturation of nascent GCase in GD cells. Additionally, increased interaction between GCase and c-Cbl, an E3 ubiquitin ligase, may be involved in the degradation and loss of GCase in GD. The findings suggest that specific molecular mediators involved in GCase maturation and degradation could be responsible for phenotypic variation among patients with the same genotypes and that these mediators could be therapeutically targeted to increase GCase activity in patients with GD.

Depletion of the Neural Precursor Cell Pool by Glucocorticoids

Annals of Neurology. Jan, 2010  |  Pubmed ID: 20186952

Glucocorticoids (GCs) are indicated for a number of conditions in obstetrics and perinatal medicine; however, the neurodevelopmental and long-term neurological consequences of early-life GC exposure are still largely unknown. Preclinical studies have demonstrated that GCs have a major influence on hippocampal cell turnover by inhibiting neurogenesis and stimulating apoptosis of mature neurons. Here we examined the fate of the limited pool of neural progenitor cells (NPCs) after GC administration during neonatal development; the impact of this treatment on hippocampal structure was also studied.

Flow Injection Solid-phase Extraction Using Multi-walled Carbon Nanotubes Packed Micro-column for the Determination of Polycyclic Aromatic Hydrocarbons in Water by Gas Chromatography-mass Spectrometry

Journal of Chromatography. A. Apr, 2010  |  Pubmed ID: 20236647

A flow injection solid-phase extraction preconcentration system using a multi-walled carbon nanotubes (MWCNTs) packed micro-column was developed for the determination of 16 polycyclic aromatic hydrocarbons (PAHs) in water by gas chromatography-mass spectrometry (GC-MS). The preconcentration of PAHs on the MWCNTs was carried out based on the adsorption retention of analytes by on-line introducing the sample into the micro-column system. Methanol was introduced to elute the retained analytes for GC-MS analysis using selected ion monitoring (SIM) mode. Important influence factors were studied in detail, such as sample acidity, sample flow rate, eluent flow rate and volume, dimensions of MWCNTs and amounts of packing material. Limits of detection of 16 PAHs for an extraction of 50 mL water sample were in the range of 0.001-0.15 microg L(-1), and the precisions (RSD) were in the range of 4-14%. The optimized method was successfully applied to the determination of 16 PAHs in surface waters, with recoveries in the range of 72-93% for real spiked sample.

Mesoporous Silica Nanoparticles Facilitate Delivery of SiRNA to Shutdown Signaling Pathways in Mammalian Cells

Small (Weinheim an Der Bergstrasse, Germany). Jun, 2010  |  Pubmed ID: 20461725

[A Non-local Means Approach for PET Image Denoising]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Apr, 2010  |  Pubmed ID: 20481301

Denoising is an important issue for medical image processing. Based on the analysis of the Non-local means algorithm recently reported by Buades A, et al. in international journals we herein propose adapting it for PET image denoising. Experimental de-noising results for real clinical PET images show that Non-local means method is superior to median filtering and wiener filtering methods and it can suppress noise in PET images effectively and preserve important details of structure for diagnosis.

Anaerobic Vs Aerobic Pathways of Carbonyl and Oxidant Stress in Human Lens and Skin During Aging and in Diabetes: A Comparative Analysis

Free Radical Biology & Medicine. Sep, 2010  |  Pubmed ID: 20541005

The effects of anaerobic (lens) vs aerobic (skin) environment on carbonyl and oxidant stress are compared using de novo and existing data on advanced glycation and oxidation products in human crystallins and collagen. Almost all modifications increase with age. Methylglyoxal hydroimidazolones, carboxymethyllysine, and carboxyethyllysine are severalfold higher in lens than in skin and markedly increase upon incubation of lens crystallins with 5mM ascorbic acid. In contrast, fructose-lysine, glucosepane crosslinks, glyoxal hydroimidazolones, metal-catalyzed oxidation (allysine), and H(2)O(2)-dependent modifications (2-aminoapidic acid and methionine sulfoxide) are markedly elevated in skin, but relatively suppressed in the aging lens. In both tissues ornithine is the dominant modification, implicating arginine residues as the principal target of the Maillard reaction in vivo. Diabetes (here mostly type 2 studied) increases significantly fructose-lysine and glucosepane in both tissues (P<0.001) but has surprisingly little effect on the absolute level of most other advanced glycation end products. However, diabetes strengthens the Spearman correlation coefficients for age-related accumulation of hydrogen peroxide-mediated modifications in the lens. Overall, the data suggest that oxoaldehyde stress involving methylglyoxal from either glucose or ascorbate is predominant in the aging noncataractous lens, whereas aging skin collagen undergoes combined attack by nonoxidative glucose-mediated modifications, as well as those from metal-catalyzed oxidation and H(2)O(2).

Biocompatibility, Biodistribution, and Drug-delivery Efficiency of Mesoporous Silica Nanoparticles for Cancer Therapy in Animals

Small (Weinheim an Der Bergstrasse, Germany). Aug, 2010  |  Pubmed ID: 20623530

Mesoporous silica nanoparticles (MSNs) are a promising material for drug delivery. In this Full Paper, MSNs are first shown to be well tolerated, as demonstrated by serological, hematological, and histopathological examinations of blood samples and mouse tissues after MSN injection. Biodistribution studies using human cancer xenografts are carried out with in vivo imaging and fluorescent microscopy imaging, as well as with inductively coupled plasma mass spectroscopy. The results show that MSNs preferentially accumulate in tumors. Finally, the drug-delivery capability of MSNs is demonstrated by following tumor growth in mice treated with camptothecin-loaded MSNs. These results indicate that MSNs are biocompatible, preferentially accumulate in tumors, and effectively deliver drugs to the tumors and suppress tumor growth.

[A New CBCT Denoising Method Based on Coefficient Classification]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Jun, 2010  |  Pubmed ID: 20649039

Denoising is an important issue for medical image processing. In this paper, a fast CBCT denoising method was proposed: CBCT images were transformed into wavelet domain with dyadic wavelet transform. According to the inter-scale relationship of wavelet coefficient magnitude sum in cone of influence (COI), wavelet coefficients were classified into two categories, then different types of coefficient were denoised by different wiener filtering based on direction window at all levels, and a new noise variation estimating method more suitable for CBCT images was proposed. Experimental results of a test image and a clinical CBCT image show that this algorithm is superior to the conventional method for wavelet shrinkage denoising. This algorithm can suppress noise in CBCT images effectively and keep up the important structure details for diagnosis, thus providing a new approach for real-time denoising clinical CBCT images.

Bub1 and CENP-F Can Contribute to Kaposi's Sarcoma-associated Herpesvirus Genome Persistence by Targeting LANA to Kinetochores

Journal of Virology. Oct, 2010  |  Pubmed ID: 20660191

The latency-associated nuclear antigen (LANA) encoded by Kaposi's sarcoma-associated herpesvirus (KSHV) is critical for segregation of viral episomes to progeny nuclei and allows for maintenance of the viral genome in newly divided daughter cells. LANA binds to KSHV terminal repeat (TR) DNA and simultaneously associates with chromatin-bound cellular proteins. This process tethers the viral episomes to host chromosomes. However, the mechanism of tethering is complex and involves multiple protein-protein interactions. Our previous proteomics studies which showed the association of LANA with centromeric protein F (CENP-F) prompted us to further study whether LANA targets centromeric proteins for persistence of KSHV episomes during cell division. Here we show that LANA colocalized with CENP-F as speckles, some of which are paired at centromeric regions of a subset of chromosomes in KSHV-infected JSC-1 cells. We also confirm that both the amino and carboxy termini of LANA can bind to CENP-F. Moreover, LANA associated with another kinetochore protein, Bub1 (budding uninhibited by benzimidazole 1), which is known to form a complex with CENP-F. Importantly, we demonstrated the dynamic association of LANA and Bub1/CENP-F and the colocalization between Bub1, LANA, and the KSHV episome tethered to the host chromosome using fluorescence in situ hybridization (FISH). Knockdown of Bub1 expression by lentivirus-delivered short hairpin RNA (shRNA) dramatically reduced the number of KSHV genome copies, whereas no dramatic effect was seen with CENP-F knockdown. Therefore, the interaction between LANA and the kinetochore proteins CENP-F and Bub1 is important for KSHV genome tethering and its segregation to new daughter cells, with Bub1 potentially playing a more critical role in the long-term persistence of the viral genome in the infected cell.

Synthesis and Preliminary Characterization of Sulfamethazine-theophylline Co-crystal

Journal of Pharmaceutical Sciences. Sep, 2010  |  Pubmed ID: 20665847

Co-crystals containing active pharmaceutical ingredients (APIs) represent a new type of pharmaceutical materials. In this work, sulfamethazine (STH) and theophylline (TP) were employed as the co-crystal formers. Neat cogrinding, solvent-drop cogrinding and slow evaporation were applied to synthesize the sulfamethazine-theophylline co-crystal (hereafter STH-TP co-crystal). The co-crystalline phase was characterized by DSC, TGA, Raman, PXRD, and dynamic vapor sorption (DVS) techniques. The STH-TP co-crystal structure was determined from single crystal X-ray diffraction data. The results show that, the STH-TP co-crystal, obtained in a 2:1 molar ratio of sulfamethazine and theophylline only by slow evaporation, possesses unique thermal, spectroscopic, and X-ray diffraction properties. Besides, in the STH-TP co-crystal, the sulfamethazine molecules form a dimer through the intermolecular hydrogen bonding (O ... H -- N), and two intermolecular hydrogen bonds (O ... H -- N and N ... H -- N) keep the theophylline attached the dimer.

The Chinese Herbal Medicine Sophora Flavescens Activates Pregnane X Receptor

Drug Metabolism and Disposition: the Biological Fate of Chemicals. Dec, 2010  |  Pubmed ID: 20736322

Sophora flavescens (SF) is an herbal medicine widely used for the treatment of viral hepatitis, cancer, viral myocarditis, gastrointestinal hemorrhage, and skin diseases. It was recently reported that SF up-regulates CYP3A expression. The mechanism of SF-induced CYP3A expression is unknown. In the current study, we tested the hypothesis that SF-induced CYP3A expression is mediated by the activation of pregnane X receptor (PXR). We used two cell lines, DPX2 and HepaRG, to investigate the role of PXR in SF-induced CYP3A expression. The DPX2 cell line is derived from HepG2 cells with the stable transfection of human PXR and a luciferase reporter gene linked with a human PXR response element identified in the CYP3A4 gene promoter. In DPX2 cells, SF activated PXR in a concentration-dependent manner. We used a metabolomic approach to identify the chemical constituents in SF, which were further analyzed for their effect on PXR activation and CYP3A regulation. One chemical in SF, N-methylcytisine, was identified as an individual chemical that activated PXR. HepaRG is a highly differentiated hepatoma cell line that mimics human hepatocytes. In HepaRG cells, N-methylcytisine significantly induced CYP3A4 expression, and this induction was suppressed by the PXR antagonist sulforaphane. These results suggest that SF induces CYP3A expression via the activation of PXR.

Widespread Genomic Instability Mediated by a Pathway Involving Glycoprotein Ib Alpha and Aurora B Kinase

The Journal of Biological Chemistry. Apr, 2010  |  Pubmed ID: 20157117

c-Myc (Myc) oncoprotein induction of genomic instability (GI) contributes to its initial transforming function and subsequent tumor cell evolution. We describe here a pathway by which Myc, via its target protein glycoprotein Ibalpha (GpIb alpha), mediates GI. Proteomic profiling revealed that the serine/threonine kinase Aurora B is down-regulated by GpIb alpha in p53-deficient primary human fibroblasts. The phenotypes of Aurora B deficiency are strikingly reminiscent of Myc or GpIb alpha overexpression and include double-stranded DNA breaks, altered nuclear size and morphology, chromatin bridges, cleavage furrow regression, and tetraploidy. During mitosis, GpIb alpha and Aurora B redistribute to the cleavage furrow along with other cleavage furrow proteins. GpIb alpha overexpression at levels comparable with those seen in some tumor cells causes the dispersal of these proteins but not Aurora B, resulting in furrow regression and cytokinesis failure. Aurora B normalization redirects the mislocalized furrow proteins to their proper location, corrects the cleavage furrow abnormalities, and restores genomic stability. Aurora B thus appears necessary for a previously unrecognized function in guiding and positioning a number of key proteins, including GpIb alpha to the cleavage furrow. These findings underscore the importance of maintaining a delicate balance among cleavage furrow-associated proteins during mitosis. Suppression of Aurora B via GpIb alpha provides a unifying and mechanistic explanation for several types of Myc-mediated GI.

Endothelial-like Cells Derived Directly from Human Tumor Xenografts

International Journal of Cancer. Journal International Du Cancer. Nov, 2010  |  Pubmed ID: 20162569

Tumor-associated endothelial cells (TAECs) harboring various genomic abnormalities have been described in human cancers although their origins remain obscure. We generated 4 human cancer cell lines tagged with multiple markers, grew them as xenografts, and characterized their TAECs. Depending on their tumor of origin, 5-40% of TAECs reproducibly expressed all tags. Tagged TAECs (tTAECS) were morphologically, immunologically and functionally similar, although not identical, to normal endothelial cells (ECs) and contained only human chromosomes. tTAECs underwent a senescent-like proliferative arrest after several in vitro passages, but could be immortalized by telomerase, thus allowing us to show that the retention of the EC phenotype was of long-term duration. In contrast, nonimmortalized tTAECs could be propagated in vivo where they incorporated into the tumor neo-vasculature. Although consistent with previous reports that some tumor cells may undergo "vasculogenic mimicry" (VM), the tumor-derived endothelial-like cells described here appear distinctly different. Moreover, their properties and behaviors are more durable than expected for cells undergoing VM, are not the result of fusions between ECs and tumor cells, and are cell autonomous. These findings could have significant implications for therapies that target tumor angiogenesis.

Annexin A2 Combined with Low-dose TPA Improves Thrombolytic Therapy in a Rat Model of Focal Embolic Stroke

Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism. Jun, 2010  |  Pubmed ID: 20068577

Recent studies showed that soluble annexin A2 dramatically increases tissue plasminogen activator (tPA)-mediated plasmin generation in vitro, and reduces thrombus formation in vivo. Here, we hypothesize that combining annexin A2 with tPA can significantly enhance thrombolysis efficacy, so that lower doses of tPA can be applied in ischemic stroke to avoid neurotoxic and hemorrhagic complications. In vitro activity assays confirmed tPA-specific amplification of plasmin generation by recombinant annexin A2. In a rat focal embolic stroke model, combination therapy with tPA and recombinant annexin A2 protein at 2 h post-ischemia decreased the effective dose required for tPA by four-fold and reduced brain infarction. Combining annexin A2 with tPA also lengthened the time window for thrombolysis. Compared with tPA (10 mg/kg) alone, the combination of annexin A2 (5 mg/kg) plus low-dose tPA (2.5 mg/kg) significantly enhanced fibrinolysis, attenuated mortality, brain infarction, and hemorrhagic transformation, even when administered at 4 h post-ischemia. Combination with recombinant annexin A2, the effective thrombolytic dose of tPA can be decreased. As a result, brain hemorrhage and infarction are reduced, and the time window for stroke reperfusion prolonged. Our present findings provide a promising new approach for enhancing tPA-based thrombolytic stroke therapy.

The Effect of a PP2A Inhibitor on the Nuclear Receptor Corepressor Pathway in Glioma

Journal of Neurosurgery. Aug, 2010  |  Pubmed ID: 20001590

Nuclear receptor corepressor (N-CoR) forms a complex that maintains neural stem cells in an undifferentiated state through transcriptional repression. Recently, it has been shown that N-CoR is overexpressed in glioblastoma multiforme (GBM) tumor stem cells and has a putative role in maintaining these cells in an undifferentiated immortal state. To determine the effects of disruption of N-CoR complex function by serine/threonine protein phosphatase 2A (PP2A) inhibition on GBM tumor cell differentiation and proliferation, the authors developed and investigated a competitive small molecule inhibitor (LB1) of PP2A in GBM.

Creation, Validation, and Quantitative Analysis of Protein Expression in Vascular Tissue Microarrays

Cardiovascular Pathology : the Official Journal of the Society for Cardiovascular Pathology. May-Jun, 2010  |  Pubmed ID: 19211265

Tissue microarrays (TMAs) are collections of multiple tissue cores placed in parallel in a single acceptor block and traditionally used to investigate protein expression in neoplastic tissues. We validated the use of TMAs to investigate protein expression in vascular segments.

Effects of Ammonium on the Antioxidative Response in Hydrilla Verticillata (L.f.) Royle Plants

Ecotoxicology and Environmental Safety. Feb, 2010  |  Pubmed ID: 19811833

To investigate ammonium toxicity, the submerged plant Hydrilla verticillata (L.f.) Royle was treated with 0.1-3.0mM ammonium for 12h and 4d. After exposure to ammonium for 4d, content of O2(-) and H2O2 increased in leaves of H. verticillata exposed to 3mM ammonium compared with control (0mM NH4Cl), while the malondialdehyde content decreased. The chlorophyll (a+b) and carotenoid concentrations decreased in H. verticillata plants exposed to 1.5-3mM ammonium for 12h and 4d. Compared with controls, the activity of superoxide dismutase, peroxidase, catalase, glutathione reductase, ascorbate peroxidase, and glutathione S-transferase increased in plants treated with ammonium for 12h, and the activity of most enzymes was further enhanced at 4d. The changes in nonprotein thiols, total glutathione, ascorbic acid, and dehydroascorbate content were also assayed. Our results suggest that ammonium induced the oxidative stress and the heated antioxidant response in H. verticillata.

Clinical and Dosimetric Risk Factors of Acute Esophagitis in Patients Treated with 3-dimensional Conformal Radiotherapy for Non-small-cell Lung Cancer

American Journal of Clinical Oncology. Jun, 2010  |  Pubmed ID: 19823071

To analyze the clinical and dosimetric risk factors of acute esophagitis (AE) in non-small-cell lung cancer (NSCLC) patients treated with 3-dimensional conformal radiotherapy (3D-CRT).

Comparison of (18)F-fluorothymidine and (18)F-fluorodeoxyglucose PET/CT in Delineating Gross Tumor Volume by Optimal Threshold in Patients with Squamous Cell Carcinoma of Thoracic Esophagus

International Journal of Radiation Oncology, Biology, Physics. Mar, 2010  |  Pubmed ID: 19910143

To determine the optimal method of using (18)F-fluorothymidine (FLT) positron emission tomography (PET)/computed tomography (CT) simulation to delineate the gross tumor volume (GTV) in esophageal squamous cell carcinoma verified by pathologic examination and compare the results with those using (18)F-fluorodeoxyglucose (FDG) PET/CT.

Isolation, Characterization and Anti-cancer Activity of SK84, a Novel Glycine-rich Antimicrobial Peptide from Drosophila Virilis

Peptides. Jan, 2010  |  Pubmed ID: 19799950

We report herein the isolation and characterization of a novel glycine-rich antimicrobial peptide purified from the larvae of Drosophila virilis. A range of chromatographic methods was used for isolation and its antibacterial activity against Bacillus subtilis was employed to screen for the most active fractions. The peptide, termed SK84 due to its N-terminal serine, C-terminal lysine and a total of 84 residues, was completed sequenced using RT-PCR cDNA cloning. SK84 contains a high level of glycine (15.5%) and a hexaglycine cluster motif in the N-terminal part. SK84 displayed antibacterial activity against the tested Gram-positive bacteria (B. subtilis, Bacillus thuringiensis and Staphylococcus aureus), but had no effect on Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli) and fungi (Saccharomyces cerevisiae, Candida albicans). SK84 had specific inhibitory effects on the proliferation of several cancer cell lines (Human leukemia THP-1, liver cancer HepG2, and breast cancer MCF-7 cells), but no hemolytic activity. The results from scanning electron microscopy observations revealed that SK84 killed THP-1 cells by destroying the cell membranes. Alignment results show that SK84 is a mature protein processed from the pseudoprotein GJ19999 from D. virilis, and is very similar to several pseudoproteins from different Drosophila species. Our results show that SK84 represents a novel glycine-rich peptide family in Drosophila species with antimicrobial and anti-cancer cell activities.

Frequency-dependent Changes in the Amplitude of Low-frequency Fluctuations in Amnestic Mild Cognitive Impairment: a Resting-state FMRI Study

NeuroImage. Mar, 2011  |  Pubmed ID: 21118724

Here we utilized resting-state functional magnetic resonance imaging (R-fMRI) to measure the amplitude of low-frequency fluctuations (ALFF) and fractional ALFF (fALFF) in 24 patients with amnestic mild cognitive impairment (aMCI) and 24 age- and sex-matched healthy controls. Two different frequency bands (slow-5: 0.01-0.027 Hz; slow-4: 0.027-0.073 Hz) were analyzed. We showed that there were widespread differences in ALFF/fALFF between the two bands in many brain regions, predominantly including the medial prefrontal cortex (MPFC), posterior cingulate cortex/precuneus (PCC/PCu), basal ganglia, and hippocampus/parahippocampal gyrus (PHG). Compared to controls, the aMCI patients had decreased ALFF/fALFF values in the PCC/PCu, MPFC, hippocampus/PHG, basal ganglia, and prefrontal regions, and increased ALFF/fALFF values mainly in several occipital and temporal regions. Specifically, we observed that the ALFF/fALFF abnormalities in the PCC/PCu, PHG, and several occipital regions were greater in the slow-5 band than in the slow-4 band. Finally, our results of functional analysis were not significantly influenced by the gray matter loss in the MCI patients, suggesting that the results reflect functional differences between groups. Together, our data suggest that aMCI patients have widespread abnormalities in intrinsic brain activity, and the abnormalities depend on the studied frequency bands of R-fMRI data.

Contrast-enhanced Whole-heart Coronary MRA at 3.0T for the Evaluation of Cardiac Venous Anatomy

The International Journal of Cardiovascular Imaging. Oct, 2011  |  Pubmed ID: 21120611

This study was designed to evaluate the value of contrast-enhanced whole-heart coronary MRA (CMRA) at 3.0T in depicting the cardiac venous anatomy. In cardiac resynchronization therapy (CRT), left ventricular (LV) pacing is achieved by positioning the LV lead in one of the tributaries of the coronary sinus (CS). Pre-implantation knowledge of the venous anatomy may help determine whether transvenous LV lead placement for CRT is feasible. Images of 51 subjects undergoing contrast-enhanced whole-heart CMRA at 3.0T were retrospectively analyzed. Data acquisition was performed using electrocardiography-triggered, navigator-gated, inversion-recovery prepared, segmented gradient-echo sequence. A 32-element cardiac coil was used for data acquisition. The visibility of the cardiac veins was graded visually using a 4-point scale (1: poor-4: excellent). The paired Student t test was used to evaluate differences in diameters of the ostium of the CS in anteroposterior and superoinferior direction. The cardiac veins were finally evaluated in 48 subjects with three anatomic variations. The diameter of the CS ostium in the superoinferior direction (1.13 ± 0.26 cm) was larger than in the anteroposterior direction (0.82 ± 0.19 cm) (P < 0.05). The mean visibility score of CS, posterior interventricular vein, posterior vein of the left ventricle, left marginal vein, and anterior interventricular vein was 4.0 ± 0.0, 3.4 ± 0.5, 3.4 ± 0.5, 3.0 ± 0.8, and 3.3 ± 0.5, respectively. In conclusion, contrast-enhanced whole-heart CMRA at 3.0T can depict the normal and variant cardiac venous anatomy.

Histone Deacetylation Directs DNA Methylation in Survivin Gene Silencing

Biochemical and Biophysical Research Communications. Jan, 2011  |  Pubmed ID: 21130077

DNA methylation and histone acetylation are major epigenetic modifications in gene silencing. In our previous research, we found that the methylated oligonucleotide (SurKex) complementary to a region of promoter of survivin could induce DNA methylation in a site-specific manner leading to survivin silencing. Here, we further studied the role of histone acetylation in survivin silencing and the relationship between histone acetylation and DNA methylation. First we observed the levels of histone H4 and H4K16 acetylation that were decreased after SurKex treatment by using the chromatin immunoprecipitation (ChIP) assay. Next, we investigated the roles of histone acetylation and DNA methylation in survivin silencing after blockade of histone deacetylation with Trichostatin A (TSA). We assessed survivin mRNA expression by RT-PCR, measured survivin promoter methylation by bisulfite sequencing and examined the level of histone acetylation by the ChIP assay. The results showed that histone deacetylation blocked by TSA reversed the effects of SurKex on inhibiting the expression of survivin mRNA, inducing a site-specific methylation on survivin promoter and decreasing the level of histone acetylation. Finally, we examined the role of histone acetylation in the expression of DNA methyltransferase 1 (DNMT1) mRNA. The results showed that histone deacetylation blocked by TSA reversed the increasing effect of histone deacetylation on the expression of survivin mRNA. This study suggests that histone deacetylation guides SurKex-induced DNA methylation in survivin silencing possibly through increasing the expression of DNMT1 mRNA.

Viral Sequence Evolution in Chinese Genotype 1b Chronic Hepatitis C Patients Experiencing Unsuccessful Interferon Treatment

Infection, Genetics and Evolution : Journal of Molecular Epidemiology and Evolutionary Genetics in Infectious Diseases. Mar, 2011  |  Pubmed ID: 21147266

The efficiencies of IFN-α based therapy in chronic genotype 1b HCV patients are still unsatisfied to date. The mechanisms underlining treatment failure remain unclear and controversial. To investigate HCV sequence evolution in unsuccessfully treated genotype 1b patients before, during and after the therapy, full-length open-reading-frame of HCV genomes at week 0, week 48 and year 5 in one breakthrough and one nonresponse patients were amplified by reverse transcription (RT)-nested-PCR and sequenced. Mutations were scored and analyzed according to their locations in the HCV genome. HCV sequences in the breakthrough patient displayed significantly more mutations during the one-year therapy than that in the nonresponse patient, with p7 and NS2 encoding regions having the highest mutation rates. Most of the mutations selected during the therapy phase in the breakthrough patient were maintained and few new mutations arose in the four-year post-therapy phase, suggesting these mutations might not compromise viral fitness. Altogether our data suggest that mutations occurred during the therapy phase in the breakthrough patient are likely driven by the action of interferon and ribavirin, and these mutations may have important effects on the responses to interferon based therapy in genotype 1b HCV patients.

CYP3A-mediated Generation of Aldehyde and Hydrazine in Atazanavir Metabolism

Drug Metabolism and Disposition: the Biological Fate of Chemicals. Mar, 2011  |  Pubmed ID: 21148252

Atazanavir (ATV) is an antiretroviral drug of the protease inhibitor class. Multiple adverse effects of ATV have been reported in clinical practice, such as jaundice, nausea, abdominal pain, and headache. The exact mechanisms of ATV-related adverse effects are unknown. It is generally accepted that a predominant pathway of drug-induced toxicity is through the generation of reactive metabolites. Our current study was designed to explore reactive metabolites of ATV. We used a metabolomic approach to profile ATV metabolism in mice and human liver microsomes. We identified 5 known and 13 novel ATV metabolites. Three potential reactive metabolites were detected and characterized for the first time: one aromatic aldehyde, one α-hydroxyaldehyde, and one hydrazine. These potential reactive metabolites were primarily generated by CYP3A. Our results provide a clue for studies on ATV-related adverse effects from the aspect of metabolic activation. Further studies are suggested to illustrate the impact of these potential reactive metabolites on ATV-related adverse effects.

A Novel Urea Amperometric Biosensor Based on Secretion of Carnation Petal Cells Modified on a Graphite-epoxy Composite Electrode

The Analyst. Feb, 2011  |  Pubmed ID: 21152632

A new kind of biosensor for the detection of urea with a high selectivity, sensitivity and wide detection range was designed based on the secretion of carnation petals cells paste covered over a graphite-epoxy composite basic electrode surface. The carnation petal paste from mashed fresh carnation petals was tightly fixed on the basic electrode surface with Teflon thin film to keep it in contact with the electrode surface. Urea in aqueous solution was detected by differential pulse voltammetry based on the oxidation peak current at 0.316 V (vs. SCE) of the secreted species of carnation petal cells during the mashing process, which interacts with urea molecules and results in the decrease of the oxidation peak current. The oxidation peak current decreases linearly with the logarithm of urea concentration in the range of 1.3 × 10(-16)-4.57 × 10(-8) M and 3.4 × 10(-7)-1.3 × 10(-1) M with a detection limit of 7.5 × 10(-16) M. The biosensor was characterized by electrochemistry and fluorescent spectrometry, and applied to the determination of urea in waste water from a river around Shenyang Normal University campus with a recovery of 104.5% (RSD is 5.00%). The presence of larger amounts of ammonium ion and nitrate ion up to the molar ratio of 10(4) do not interfere with the urea detection.

Spatial Patterns of Intrinsic Brain Activity in Mild Cognitive Impairment and Alzheimer's Disease: a Resting-state Functional MRI Study

Human Brain Mapping. Oct, 2011  |  Pubmed ID: 21077137

We used resting-state functional MRI to investigate spatial patterns of spontaneous brain activity in 22 healthy elderly subjects, as well as 16 mild cognitive impairment (MCI) and 16 Alzheimer's disease (AD) patients. The pattern of intrinsic brain activity was measured by examining the amplitude of low-frequency fluctuations (ALFF) of blood oxygen level dependent signal during rest. There were widespread ALFF differences among the three groups throughout the frontal, temporal, and parietal cortices. Both AD and MCI patients showed decreased activity mainly in the medial parietal lobe region and lentiform nucleus, while there was increased activity in the lateral temporal regions and superior frontal and parietal regions as compared with controls. Compared with MCI, the AD patients showed decreased activity in the medial prefrontal cortex and increased activity in the superior frontal gyrus and inferior and superior temporal gyri. Specifically, the most significant ALFF differences among the groups appeared in the posterior cingulate cortex, with a reduced pattern of activity when comparing healthy controls, MCI, and AD patients. Additionally, we also showed that the regions with ALFF changes had significant correlations with the cognitive performance of patients as measured by mini-mental state examination scores. Finally, while taking gray matter volume as covariates, the ALFF results were approximately consistent with those without gray matter correction, implying that the functional analysis could not be explained by regional atrophy. Together, our results demonstrate that there is a specific pattern of ALFF in AD and MCI, thus providing insights into biological mechanisms of the diseases.

Epstein-Barr Virus Nuclear Antigen 1 (EBNA1) Confers Resistance to Apoptosis in EBV-positive B-lymphoma Cells Through Up-regulation of Survivin

Virology. Feb, 2011  |  Pubmed ID: 21093004

Resistance to apoptosis is an important component of the overall mechanism which drives the tumorigenic process. EBV is a ubiquitous human gamma-herpesvirus which preferentially establishes latent infection in viral infected B-lymphocytes. EBNA1 is typically expressed in most forms of EBV-positive malignancies and is important for replication of the latent episome in concert with replication of the host cells. Here, we investigate the effects of EBNA1 on survivin up-regulation in EBV-infected human B-lymphoma cells. We present evidence which demonstrates that EBNA1 forms a complex with Sp1 or Sp1-like proteins bound to their cis-element at the survivin promoter. This enhances the activity of the complex and up-regulates survivin. Knockdown of survivin and EBNA1 showed enhanced apoptosis in infected cells and thus supports a role for EBNA1 in suppressing apoptosis in EBV-infected cells. Here, we suggest that EBV encoded EBNA1 can contribute to the oncogenic process by up-regulating the apoptosis suppressor protein, survivin in EBV-associated B-lymphoma cells.

Promoting Effects of Ganoderma Lucidum Polysaccharides on B16F10 Cells to Activate Lymphocytes

Basic & Clinical Pharmacology & Toxicology. Mar, 2011  |  Pubmed ID: 20964805

The immune system in patients with cancer often fails to control tumour growth because of deficient immunogenicity of tumour cells. Ganoderma lucidum polysaccharides (Gl-PS) are believed to have anti-tumour effects by boosting host immune function. Additionally, Gl-PS may have some direct effects on tumour cells in the activation of lymphocytes, thus enhancing the immunogenicity of tumour cells. We tested the effects of Gl-PS in lymphocyte activation by incubating Gl-PS with a tumour cell line deficient in antigen presentation. Our study showed that Gl-PS can promote B16F10 melanoma cells to induce lymphocyte proliferation, CD69 and FasL expression and IFN-γ production, indicating that Gl-PS can improve the nature of B16F10 cells to activate lymphocytes. Furthermore, H-2D(b) [a major histocompatibility (MHC) class I molecule], and B7-1 and B7-2 (two prominent co-stimulatory molecules expressed on B16F10 cells) were enhanced by Gl-PS, suggesting that these molecules may at least partially be involved in the process of Gl-PS on B16F10 cells to activate lymphocytes.

Pharmacologic Modulation of Serine/threonine Phosphorylation Highly Sensitizes PHEO in a MPC Cell and Mouse Model to Conventional Chemotherapy

PloS One. 2011  |  Pubmed ID: 21339823

The failure of cytotoxic cancer regimens to cure the most drug-resistant, well-differentiated solid tumors has been attributed to the heterogeneity of cell types that differ in their capacities for growth, differentiation, and metastases. We investigated the effect of LB1, a small molecule inhibitor of serine/threonine protein phosphatase 2A (PP2A), on its ability to inhibit a low growth fraction and highly drug-resistant solid neuroendocrine tumor, such as metastatic pheochromocytoma (PHEO). Subsequently, we evaluated the increased efficacy of chemotherapy combined with LB1.

Epstein-Barr Virus Nuclear Antigen 3C Facilitates G1-S Transition by Stabilizing and Enhancing the Function of Cyclin D1

PLoS Pathogens. 2011  |  Pubmed ID: 21347341

EBNA3C, one of the Epstein-Barr virus (EBV)-encoded latent antigens, is essential for primary B-cell transformation. Cyclin D1, a key regulator of G1 to S phase progression, is tightly associated and aberrantly expressed in numerous human cancers. Previously, EBNA3C was shown to bind to Cyclin D1 in vitro along with Cyclin A and Cyclin E. In the present study, we provide evidence which demonstrates that EBNA3C forms a complex with Cyclin D1 in human cells. Detailed mapping experiments show that a small N-terminal region which lies between amino acids 130-160 of EBNA3C binds to two different sites of Cyclin D1- the N-terminal pRb binding domain (residues 1-50), and C-terminal domain (residues 171-240), known to regulate Cyclin D1 stability. Cyclin D1 is short-lived and ubiquitin-mediated proteasomal degradation has been targeted as a means of therapeutic intervention. Here, we show that EBNA3C stabilizes Cyclin D1 through inhibition of its poly-ubiquitination, and also increases its nuclear localization by blocking GSK3β activity. We further show that EBNA3C enhances the kinase activity of Cyclin D1/CDK6 which enables subsequent ubiquitination and degradation of pRb. EBNA3C together with Cyclin D1-CDK6 complex also efficiently nullifies the inhibitory effect of pRb on cell growth. Moreover, an sh-RNA based strategy for knock-down of both cyclin D1 and EBNA3C genes in EBV transformed lymphoblastoid cell lines (LCLs) shows a significant reduction in cell-growth. Based on these results, we propose that EBNA3C can stabilize as well as enhance the functional activity of Cyclin D1 thereby facilitating the G1-S transition in EBV transformed lymphoblastoid cell lines.

Salicylic Acid Involved in the Regulation of Nutrient Elements Uptake and Oxidative Stress in Vallisneria Natans (Lour.) Hara Under Pb Stress

Chemosphere. Jun, 2011  |  Pubmed ID: 21377190

In this study, the alterations in nutrient elements content, reactive oxygen species level and antioxidant response were studied in leaves of Vallisneria natans (Lour.) Hara exposed to salicylic acid (SA, 10 or 100 μM), or Pb (50 μM) or their combinations for 4d. No significant alterations in Mn and Ca content were observed but content of Cu, Zn, Fe and P decreased in plants exposed to SA alone. SA application inhibited the uptake of Pb and partially reversed Pb-induced the alterations in Mn, Ca and Fe content in leaves of V. natans exposed to 50 μM Pb. The decreased chlorophyll (a+b) and increased malondialdehyde and O(2-) and H(2)O(2) content were detected in plants exposed to 100 μM SA, 50 μM Pb, 10 μM SA+50 μM Pb or 100 μM SA+50 μM Pb. Application SA partially inhibited Pb-induced the increase of malondialdehyde, O(2-) and H(2)O(2) content. 100 μM SA decreased the activity of NADH oxidase and the content of non-protein thiols, carotenoids and ascorbic acid and increased the content of dehydroascorbate in plants treated with or without Pb. SA alone decreased the ascorbate peroxidase activity and increased the catalase and peroxidase activity, while SA application increased catalase activity but had no significant effect on ascorbate peroxidase and peroxidase activity in V. natans exposed to Pb. The results indicate that SA involves in the regulation of Pb uptake, nutrient balance and oxidative stress.

The Synthesis of Pteroyl-lys Conjugates and Its Application As Technetium-99m Labeled Radiotracer for Folate Receptor-positive Tumor Targeting

Bioorganic & Medicinal Chemistry Letters. Apr, 2011  |  Pubmed ID: 21377880

Aiming to develop a new (99m)Tc-labeled folate derivative for FR-positive tumor imaging, a simpler method has been established to synthesize the folate-drug conjugates with free α-carboxyl group. In this study, the conjugate pteroyl-lys-HYNIC was synthesized and labeled with (99m)Tc using tricine and TPPTS as co-ligands. The radiochemical purity of the final complex (99m)Tc(HYNIC-lys-pteroyl)(tricine/TPPTS), 5 was high (>98%), and it remained stable in saline and plasma over 6h after preparation. The biologic evaluation results showed that the (99m)Tc labeled pteroyl-lys conjugate was able to specifically target the FR-positive tumor cells and tissues both in vitro and in vivo, highlighting its potential as an effective folate receptor targeted agent for tumor imaging.

Missense Mutations in the NF2 Gene Result in the Quantitative Loss of Merlin Protein and Minimally Affect Protein Intrinsic Function

Proceedings of the National Academy of Sciences of the United States of America. Mar, 2011  |  Pubmed ID: 21383154

Neurofibromatosis type 2 (NF2) is a multiple neoplasia syndrome and is caused by a mutation of the NF2 tumor suppressor gene that encodes for the tumor suppressor protein merlin. Biallelic NF2 gene inactivation results in the development of central nervous system tumors, including schwannomas, meningiomas, ependymomas, and astrocytomas. Although a wide variety of missense germline mutations in the coding sequences of the NF2 gene can cause loss of merlin function, the mechanism of this functional loss is unknown. To gain insight into the mechanisms underlying loss of merlin function in NF2, we investigated mutated merlin homeostasis and function in NF2-associated tumors and cell lines. Quantitative protein and RT-PCR analysis revealed that whereas merlin protein expression was significantly reduced in NF2-associated tumors, mRNA expression levels were unchanged. Transfection of genetic constructs of common NF2 missense mutations into NF2 gene-deficient meningioma cell lines revealed that merlin loss of function is due to a reduction in mutant protein half-life and increased protein degradation. Transfection analysis also demonstrated that recovery of tumor suppressor protein function is possible, indicating that these mutants maintain intrinsic functional capacity. Further, increased expression of mutant protein is possible after treatment with specific proteostasis regulators, implicating protein quality control systems in the degradative fate of mutant tumor suppressor proteins. These findings provide direct insight into protein function and tumorigenesis in NF2 and indicate a unique treatment paradigm for this disorder.

In Vitro DNA-binding Profile of Transcription Factors: Methods and New Insights

The Journal of Endocrinology. Jul, 2011  |  Pubmed ID: 21389103

The DNA-binding specificity of transcription factors (TFs) has broad impacts on cell physiology, cell development and in evolution. However, the DNA-binding specificity of most known TFs still remains unknown. The specificity of a TF protein is determined by its relative affinity to all possible binding sites. In recent years, the development of several in vitro techniques permits high-throughput determination of relative binding affinity of a TF to all possible k bp-long DNA sequences, thus greatly promoting the characterization of DNA-binding specificity of many known TFs. All DNA sequences that can be bound by a TF with various binding affinities form their DNA-binding profile (DBP). The DBP is important to generate an accurate DNA-binding model, identify all DNA-binding sites and target genes of TFs in the whole genome, and build transcription regulatory network. This study reviewed these techniques, especially two master techniques: double-stranded DNA microarray and systematic evolution of ligands by exponential enrichment in combination with parallel DNA sequencing techniques (SELEX-seq).

Common and Dissociable Neural Correlates Associated with Component Processes of Inductive Reasoning

NeuroImage. Jun, 2011  |  Pubmed ID: 21406238

The ability to draw numerical inductive reasoning requires two key cognitive processes, identification and extrapolation. This study aimed to identify the neural correlates of both component processes of numerical inductive reasoning using event-related fMRI. Three kinds of tasks: rule induction (RI), rule induction and application (RIA), and perceptual judgment (Jud) were solved by twenty right-handed adults. Our results found that the left superior parietal lobule (SPL) extending into the precuneus and left dorsolateral prefrontal cortex (DLPFC) were commonly recruited in the two components. It was also observed that the fronto-parietal network was more specific to identification, whereas the striatal-thalamic network was more specific to extrapolation. The findings suggest that numerical inductive reasoning is mediated by the coordination of multiple brain areas including the prefrontal, parietal, and subcortical regions, of which some are more specific to demands on only one of these two component processes, whereas others are sensitive to both.

A Visual Method for Direct Selection of High-producing Pichia Pastoris Clones

BMC Biotechnology. 2011  |  Pubmed ID: 21418613

The methylotrophic yeast, Pichia pastoris, offers the possibility to generate a high amount of recombinant proteins in a fast and easy way to use expression system. Being a single-celled microorganism, P. pastoris is easy to manipulate and grows rapidly on inexpensive media at high cell densities. A simple and direct method for the selection of high-producing clones can dramatically enhance the whole production process along with significant decrease in production costs.

Effects of Pb Stress on Nutrient Uptake and Secondary Metabolism in Submerged Macrophyte Vallisneria Natans

Ecotoxicology and Environmental Safety. Jul, 2011  |  Pubmed ID: 21440937

For better understanding the metabolic adaptations to Pb stress in submerged plants, the alterations in mineral elements uptake and in secondary metabolism were studied in leaves of Vallisneria natans (Lour.) Hara exposed to 0-100μM Pb for 0-7d. Pb content increased in leaves in a dose-dependent way. The increase of calcium, magnesium and iron content and the decrease of phosphorus, potassium and manganese content were detected in leaves of V. natans under Pb stress, while no significant changes were detected in copper and zinc concentration. Meanwhile, there was an increase in the concentrations of total phenolic and flavonoids. Pb treatment caused an increase in the catalytic activities of shikimate dehydrogenase, phenylalanine ammonialyase and polyphenol oxidase. The results suggest that nutrient uptake and secondary metabolism were actively regulated by V. natans plants in response to Pb stress.

[Sero-epidemiological Investigation on Rickettsia Typhi, Bartonella Henselae and Orientia Tsutsugamushi in Farmers from Rural Areas of Tianjin, 2007 - 2009.]

Zhonghua Liu Xing Bing Xue Za Zhi = Zhonghua Liuxingbingxue Zazhi. Mar, 2011  |  Pubmed ID: 21457660

OBJECTIVE: To study the sero-epidemiological status regarding Rickettsia (R.) typhi, Bartonella (B.) henselae and Orientia (O.) tsutsugamushi in farmers from rural areas of Tianjin. METHODS: Field epidemiological surveys were performed in 8 districts (county) of Tianjin city from 2007 to 2009. 886 farmers were randomly recruited and their serum samples collected to detect the specific antibodies of R. typhi, B. henselae and O. tsutsugamushi by micro-indirect immunoflorescence (IFA). RESULTS: The total antibody positive rates of R. typhi increased from 5.0% to 58.2% while B. henselae had an increase from 2.6% to 14.5% and O. tsutsugamushi increased from 1.8% to 39.8%. Geographic distribution showed that farmers living in the central and southeast areas were higher than that in other areas. CONCLUSION: Infections of both R. typhi, B. henselae and O. tsutsugamushi in farmers from Tianjin areas were popular and the antibody positive rates of R. typhi, B. henselae and O. tsutsugamushi had an annual increase.

Abnormal Amygdala Connectivity in Patients with Primary Insomnia: Evidence from Resting State FMRI

European Journal of Radiology. Mar, 2011  |  Pubmed ID: 21458943

BACKGROUND: Neurobiological mechanisms underlying insomnia are poorly understood. Previous findings indicated that dysfunction of the emotional circuit might contribute to the neurobiological mechanisms underlying insomnia. The present study will test this hypothesis by examining alterations in functional connectivity of the amygdala in patients with primary insomnia (PI). METHODS: Resting-state functional connectivity analysis was used to examine the temporal correlation between the amygdala and whole-brain regions in 10 medication-naive PI patients and 10 age- and sex-matched healthy controls. Additionally, the relationship between the abnormal functional connectivity and insomnia severity was investigated. RESULTS: We found decreased functional connectivity mainly between the amygdala and insula, striatum and thalamus, and increased functional connectivity mainly between the amygdala and premotor cortex, sensorimotor cortex in PI patients as compared to healthy controls. The connectivity of the amygdala with the premotor cortex in PI patients showed significant positive correlation with the total score of the Pittsburgh Sleep Quality Index (PSQI). CONCLUSIONS: The decreased functional connectivity between the amygdala and insula, striatum, and thalamus suggests that dysfunction in the emotional circuit might contribute to the neurobiological mechanisms underlying PI. The increased functional connectivity of the amygdala with the premotor and sensorimotor cortex demonstrates a compensatory mechanism to overcome the negative effects of sleep deficits and maintain the psychomotor performances in PI patients.

Profiling the Reactive Metabolites of Xenobiotics Using Metabolomic Technologies

Chemical Research in Toxicology. May, 2011  |  Pubmed ID: 21469730

A predominant pathway of xenobiotic-induced toxicity is initiated by bioactivation. Characterizing reactive intermediates will provide information on the structure of reactive species, thereby defining a potential bioactivation mechanism. Because most reactive metabolites are not stable, it is difficult to detect them directly. Reactive metabolites can form adducts with trapping reagents, such as glutathione, which makes the reactive metabolites detectable. However, it is challenging to "fish" these adducts out from a complex biological matrix, especially for adducts generated via uncommon metabolic pathways. In this regard, we developed a novel approach based upon metabolomic technologies to screen trapped reactive metabolites. The bioactivation of pulegone, acetaminophen, and clozapine were reexamined by using this metabolomic approach. In all these cases, a large number of trapped reactive metabolites were readily identified. These data indicate that this metabolomic approach is an efficient tool to profile xenobiotic bioactivation.

Dosimetric Comparison of RapidArc with Fixed Gantry Intensity-modulated Radiotherapy Treatment for Multiple Liver Metastases Radiotherapy

Medical Dosimetry : Official Journal of the American Association of Medical Dosimetrists. 2011  |  Pubmed ID: 21474299

We wanted to compare the dosimetric difference and treatment efficiency of RapidArc and fixed gantry intensity-modulated radiotherapy treatment (IMRT) for multiple liver metastases. Computed tomography datasets of 10 patients were studied retrospectively. IMRT plans were generated using 5 fields and RapidArc using either 1 or 2 arcs. The dose distribution of planning target volume (PTV), organs at risk (OARs), and the normal tissue were compared. Monitor units and treatment time were scored to measure expected treatment efficiency. Both RapidArc and IMRT plans resulted in equivalent target coverage. There was no statistically significant difference for the maximum and the minimum dose of PTV. RapidArc plans achieved an improved conformity index compared with IMRT (RA1 = 1.68 ± 0.27, RA2 = 1.61 ± 0.25, IMRT = 1.80 ± 0.37). For OARs, all techniques respected planning objectives. RapidArc plans had a lower dose in V(40) of small bowel than IMRT, but were higher in mean dose of kidneys. Concerning the V(5), V(10), and V(15) of healthy tissue, RapidArc plans were higher than IMRT. However, the V(20), V(25), and V(30) of healthy tissue in RapidArc plans were lower than IMRT. Monitor units per fraction of RapidArc plans were about 40% or 46% of IMRT. Compared with IMRT plans, treatment time of RapidArc plans were reduced by 60% or 70%. All techniques respected planning objectives. RapidArc showed statistical improvements in conformity index and healthy tissue sparing with uncompromised target coverage. This, in combination with fewer monitor units and short delivery time, can lead to clinically significant advances for the treatment of multiple liver metastases.

Ganoderma Lucidum Polysaccharides Antagonize the Suppression on Lymphocytes Induced by Culture Supernatants of B16F10 Melanoma Cells

The Journal of Pharmacy and Pharmacology. May, 2011  |  Pubmed ID: 21492175

Tumour cells produce factors such as interleukin 10 (IL-10), transforming growth factor β1 (TGF-β1) and vascular endothelial growth factor (VEGF) that suppress the function of immune cells or induce apoptosis of immune cells. One of the most important goals of tumour immunotherapy is to antagonize this suppression on immune cells. Ganoderma lucidum polysaccharides (Gl-PS) may have this potential. The purpose of this study was to determine the antagonistic effects of Gl-PS on the suppression induced by B16F10 melanoma cell culture supernatant (B16F10-CS) on lymphocytes.

The Single RBP-Jkappa Site Within the LANA Promoter is Crucial for Establishing Kaposi's Sarcoma-associated Herpesvirus Latency During Primary Infection

Journal of Virology. Jul, 2011  |  Pubmed ID: 21507979

Kaposi's sarcoma-associated herpesvirus (KSHV; or human herpesvirus 8 [HHV8]) is implicated in the pathogenesis of many human malignancies including Kaposi's sarcoma (KS), multicentric Castleman's disease (MCD), and primary effusion lymphoma (PEL). KSHV infection displays two alternative life cycles, referred to as the latent and lytic or productive cycle. Previously, we have reported that the replication and transcription activator (RTA), a major lytic cycle transactivator, contributes to the development of KSHV latency by inducing latency-associated nuclear antigen (LANA) expression during early stages of infection by targeting RBP-Jκ, the master regulator of the Notch signaling pathway. Here, we generated a bacterial artificial chromosome (BAC) KSHV recombinant virus with a deletion of the RBP-Jκ site within the LANA promoter to evaluate the function of the RBP-Jκ cognate site in establishing primary latent infection. The results showed that genetic disruption of the RBP-Jκ binding site within the KSHV LANA promoter led to enhanced expression of the KSHV-encoded immediate early RTA, resulting in an increase in lytic replication during primary infection of human peripheral blood mononuclear cells (PBMCs). This system provides a powerful tool for use in indentifying additional cellular and viral molecules involved in LANA-mediated latency maintenance during the early stages of KSHV infection.

A Follow-up Study of Women with a History of Severe Preeclampsia: Relationship Between Metabolic Syndrome and Preeclampsia

Chinese Medical Journal. Mar, 2011  |  Pubmed ID: 21518575

Women with a history of preeclampsia have twice the risk of cardiovascular diseases, and there is a graded relationship between the severity of preeclampsia and the risk of cardiac disease. Moreover, metabolic scores are associated with developing preeclampsia. However, since there are no diagnostic criteria for metabolic syndrome during pregnancy and pregnant women undergo metabolic changes, it is difficult to elucidate the relationship between preeclampsia and metabolic syndrome. We carried out a cross-sectional study to investigate the relationship between metabolic syndrome and preeclampsia among women with a history of severe preeclampsia shortly after an indexed pregnancy.

Synthesis and in Vitro/in Vivo Evaluation of 99mTc-labeled Folate Conjugates for Folate Receptor Imaging

Nuclear Medicine and Biology. May, 2011  |  Pubmed ID: 21531293

Folate receptor (FR) is a potential molecular target for radionuclide imaging since it is overexpressed in many human epithelial tumor cells. In this study, a novel folate conjugate was synthesized and labeled with (99m)Tc using different coligands. In vitro and in vivo evaluations of these complexes have been done to explore the effect of coligands on the stable, affinity and pharmacokinetic properties.

Rapid On-site Detection of Acidovorax Avenae Subsp. Citrulli by Gold-labeled DNA Strip Sensor

Biosensors & Bioelectronics. Jun, 2011  |  Pubmed ID: 21536424

Acidovorax avenae subsp. citrulli (AAC) is one of the most harmful diseases in cucurbit production. A rapid and sensitive DNA strip sensor was constructed based on gold nanoparticle-labeled oligonucleotide probes for the detection of AAC. Both the qualitative and semi-quantitative detections of target DNA were successfully achieved using the developed DNA strip sensor. The qualitative limit of detection (LOD) of the strip sensor was determined as 4 nM. The LOD for the semi-quantitative detection was calculated to be 0.48 nM in the range of 0-10 nM. The genomic DNA was detected directly using the DNA strip sensor without any further treatment. This DNA strip sensor is a potentially useful tool for rapid on-site DNA screening.

Applications of IMAT in Cervical Esophageal Cancer Radiotherapy: a Comparison with Fixed-field IMRT in Dosimetry and Implementation

Journal of Applied Clinical Medical Physics / American College of Medical Physics. 2011  |  Pubmed ID: 21587177

This study aimed to compare fixed-field, intensity-modulated radiotherapy (f-IMRT) with intensity-modulated arc therapy (IMAT) treatment plans in dosimetry and practical application for cervical esophageal carcinoma. For ten cervical esophageal carcinoma cases, f-IMRT plan (seven fixed-fields) and two IMAT plans, namely RA (coplanar 360° arcs) and RAx (coplanar 360° arcs without sectors from 80° to 110°, and 250° to 280°), were generated. DVHs were adopted for the statistics of above parameters, as well as conformal index (CI), homogeneity index (HI), dose-volumetric parameters of normal tissues, total accelerator output MUs and total treatment time. There were differences between RAx and f-IMRT, as well as RA in PTV parameters such as HI, V(95%) and V(110%), but not in CI. RAx reduced lung V₅ from (50.9% ± 9.8% in f-IMRT and (51.4% ± 10.8% in RA to (49.3% ± 10.4% in RAx (p < 0.05). However, lung V₃₀, V₄₀, V₅₀ and MLD increased in RAx. There was no difference in the mean heart dose in three plans. Total MU was reduced from 1174.8 ± 144.6 in f-IMRT to 803.8 ± 122.2 in RA and 736.2 ± 186.9 in RAx (p < 0.05). Compared with f-IMRT, IMAT reduced low dose volumes of lung and total MU on the basis of meeting clinical requirements.

Synthesis of Biomolecule-modified Mesoporous Silica Nanoparticles for Targeted Hydrophobic Drug Delivery to Cancer Cells

Small (Weinheim an Der Bergstrasse, Germany). Jul, 2011  |  Pubmed ID: 21595023

Synthetic methodologies integrating hydrophobic drug delivery and biomolecular targeting with mesoporous silica nanoparticles are described. Transferrin and cyclic-RGD peptides are covalently attached to the nanoparticles utilizing different techniques and provide selectivity between primary and metastatic cancer cells. The increase in cellular uptake of the targeted particles is examined using fluorescence microscopy and flow cytometry. Transferrin-modified silica nanoparticles display enhancement in particle uptake by Panc-1 cancer cells over that of normal HFF cells. The endocytotic pathway for these particles is further investigated through plasmid transfection of the transferrin receptor into the normal HFF cell line, which results in an increase in particle endocytosis as compared to unmodified HFF cells. By designing and attaching a synthetic cyclic-RGD, selectivity between primary cancer cells (BT-549) and metastatic cancer cells (MDA-MB 435) is achieved with enhanced particle uptake by the metastatic cancer cell line. Incorporation of the hydrophobic drug Camptothecin into these two types of biomolecular-targeted nanoparticles causes an increase in mortality of the targeted cancer cells compared to that caused by both the free drug and nontargeted particles. These results demonstrate successful biomolecular-targeted hydrophobic drug delivery carriers that selectively target specific cancer cells and result in enhanced drug delivery and cell mortality.

Proteomic Identification of Glutamine Synthetase As a Differential Marker for Oligodendrogliomas and Astrocytomas

Journal of Neurosurgery. Oct, 2011  |  Pubmed ID: 21682567

Astrocytomas and oligodendrogliomas are primary CNS tumors that remain a challenge to differentiate histologically because of their morphological variability and because there is a lack of reliable differential diagnostic markers. To identify proteins that are differentially expressed between astrocytomas and oligodendrogliomas, the authors analyzed the proteomic expression patterns and identified uniquely expressed proteins in these neoplasms.

A Novel Method Based on High Resolution Melting (HRM) Analysis for MIRU-VNTR Genotyping of Mycobacterium Tuberculosis

Journal of Microbiological Methods. Sep, 2011  |  Pubmed ID: 21689691

The mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) method is one of the most important methods that have been used in recent years for genotyping Mycobacterium tuberculosis. Agarose gel electrophoresis and capillary electrophoresis have been used to determine the size of amplicons, however, both of these methods have shortcomings. Here, we develop and evaluate a novel method for MIRU-VNTR typing based on high resolution melting (HRM) analysis. The MIRU40 locus was selected to evaluate different real-time PCR machines and the accuracy of our method; the Roche LightCycler 480 provided greatest consistency between the T(m) value and repeat number and was used in subsequent evaluations. Our method gives greater accuracy in comparison with conventional agarose gel electrophoresis (98.9% vs. 90.9%, p=0.017), and, with the help of fitting formulae, can be used to obtain the number of MIRU tandem repeats from the T(m) value. To validate our method we analyzed 12 classical MIRU loci to genotype 88 clinical isolates. The number of MIRU tandem repeats was determined accurately, quickly and conveniently.

Bacterial Proteome of Streptococcus Pneumoniae Through Multidimensional Separations Coupled with LC-MS/MS

Omics : a Journal of Integrative Biology. Jul-Aug, 2011  |  Pubmed ID: 21699404

Streptococcus pneumoniae is a major human respiratory pathogen causing considerable morbidity and mortality worldwide. In order to better understand the pathogenesis of S. pneumoniae, we employed SDS-PAGE combined with LC-MS/MS analysis and in-solution digestion coupled with 2D-LC-MS/MS to obtain the whole-cell proteome of the bacterium. Among the identified 1,210 proteins, 345 proteins were annotated for cellular components, 613 for biological processes, and 421 for molecular functions. Important virulence-associated surface proteins such as Eno, ZmpB, and PrtA were identified. Classification analysis and protein-protein interaction map revealed that these identified proteins are involved in many biological processes including protein biosynthesis, protein folding and proteolysis, cell cycle, or regulation and carbohydrate metabolism. These data represent a comprehensive reference map of S. pneumoniae proteome, providing a useful source for further analysis of the virulence factors and the regulatory network involved in the pathogenesis of the bacterium.

Synthesis and Evaluation of Novel Gonadotropin-releasing Hormone Receptor-targeting Peptides

Bioconjugate Chemistry. Aug, 2011  |  Pubmed ID: 21749045

The purpose of this study was to develop novel radiolabeled gonadotropin-releasing hormone (GnRH) receptor-targeting peptides for breast cancer imaging. Three novel 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-conjugated GnRH peptides were designed and synthesized. The radiometal chelator DOTA was conjugated to the epsilon or alpha amino group of D-lysine, or the epsilon amino group of L-lysine via an Ahx {aminohexanoic acid} linker to generate DOTA-Ahx-(D-Lys(6)-GnRH1), DOTA-Ahx-(D-Lys(6)-GnRH2) and DOTA-Ahx-(L-Lys(6)-GnRH3), respectively. The conjugation of the DOTA to the epsilon amino group of D-lysine (rather than alpha amino group of D-lysine nor epsilon amino group of L-lysine) maintained the nanomolar GnRH receptor binding affinity. The IC(50) values of DOTA-Ahx-(D-Lys(6)-GnRH1), DOTA-Ahx-(D-Lys(6)-GnRH2) and DOTA-Ahx-(L-Lys(6)-GnRH3) were 36.1 nM, 10.6 mM and 4.3 mM, respectively. Since only DOTA-Ahx-(D-Lys(6)-GnRH1) displayed nanomolar receptor binding affinity, the specific GnRH receptor binding of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) was determined in human GnRH receptor membrane preparations. Furthermore, the biodistribution and tumor imaging properties of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) were examined in MDA-MB-231 human breast cancer-xenografted nude mice. (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) exhibited specific GnRH receptor binding and rapid tumor uptake (1.76 ± 0.58% ID/g at 0.5 h postinjection) coupled with fast whole-body clearance through the urinary system. The MDA-MB-231 human breast cancer-xenografted tumor lesions were clearly visualized by single photon emission computed tomography (SPECT)/CT at 1 h postinjection of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1). The profound impact of DOTA position on the binding affinity of the GnRH peptide provided a new insight into the design of novel radiolabeled GnRH peptides. The successful imaging of MDA-MB-231 human breast cancer-xenografted tumor lesions using (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) suggested its potential as a novel imaging probe for human breast cancer imaging.

Proton Magnetic Resonance Spectroscopy in Patients with Symptomatic Unilateral Internal Carotid Artery / Middle Cerebral Artery Stenosis or Occlusion

Journal of Magnetic Resonance Imaging : JMRI. Oct, 2011  |  Pubmed ID: 21774028

To explore the value of proton magnetic resonance spectroscopy imaging ((1)H-MRSI) in patients with stenosis or occlusion of the internal carotid artery (ICA) / middle cerebral artery (MCA).

S100B and APP Promote a Gliocentric Shift and Impaired Neurogenesis in Down Syndrome Neural Progenitors

PloS One. 2011  |  Pubmed ID: 21779383

Down syndrome (DS) is a developmental disorder associated with mental retardation (MR) and early onset Alzheimer's disease (AD). These CNS phenotypes are attributed to ongoing neuronal degeneration due to constitutive overexpression of chromosome 21 (HSA21) genes. We have previously shown that HSA21 associated S100B contributes to oxidative stress and apoptosis in DS human neural progenitors (HNPs). Here we show that DS HNPs isolated from fetal frontal cortex demonstrate not only disturbances in redox states within the mitochondria and increased levels of progenitor cell death but also transition to more gliocentric progenitor phenotypes with a consequent reduction in neuronogenesis. HSA21 associated S100B and amyloid precursor protein (APP) levels are simultaneously increased within DS HNPs, their secretions are synergistically enhanced in a paracrine fashion, and overexpressions of these proteins disrupt mitochondrial membrane potentials and redox states. HNPs show greater susceptibility to these proteins as compared to neurons, leading to cell death. Ongoing inflammation through APP and S100B overexpression further promotes a gliocentric HNPs phenotype. Thus, the loss in neuronal numbers seen in DS is not merely due to increased HNPs cell death and neurodegeneration, but also a fundamental gliocentric shift in the progenitor pool that impairs neuronal production.

Amnestic Mild Cognitive Impairment: Functional MR Imaging Study of Response in Posterior Cingulate Cortex and Adjacent Precuneus During Problem-solving Tasks

Radiology. Nov, 2011  |  Pubmed ID: 21788526

To compare the blood oxygen level-dependent (BOLD) response, measured with functional magnetic resonance (MR) imaging, in the posterior cingulate cortex (PCC) and adjacent precuneus regions between healthy control subjects and patients with amnestic mild cognitive impairment (MCI) during problem-solving tasks.

A 2:1 Sulfamethazine-theophylline Cocrystal Exhibiting Two Tautomers of Sulfamethazine

Acta Crystallographica. Section C, Crystal Structure Communications. Aug, 2011  |  Pubmed ID: 21817798

In the title cocrystal, 4-amino-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide-4-amino-N-(4,6-dimethyl-1,2-dihydropyrimidin-2-ylidene)benzenesulfonamide-1,3-dimethyl-7H-purine-2,6-dione (1/1/1), C(7)H(8)N(4)O(2)·2C(12)H(14)N(4)O(2)S, two sulfamethazine molecules cocrystallize with a single molecule of theophylline. Each molecule of sulfamethazine forms a hydrogen-bonded ribbon along the b axis crosslinked by further hydrogen bonding. The two sulfamethazine molecules exhibit a hydrogen-shift isomerization so that the crystal structure contains both tautomeric forms. Calculation of their relative energies showed that the tautomer protonated at the chain N atom is considerably more stable than the one where an N atom in the aromatic ring is protonated. The latter, here observed for the first time, is stabilized through strong intermolecular interactions with the theophylline molecules.

Baseline and Longitudinal Patterns of Hippocampal Connectivity in Mild Cognitive Impairment: Evidence from Resting State FMRI

Journal of the Neurological Sciences. Oct, 2011  |  Pubmed ID: 21821265

The hippocampus is believed to have close relationship with many cerebral cortexes and constitute memory network to modulate and facilitate communication, which makes it especially interesting and meaningful in the study of functional connectivity in mild cognitive impairment (MCI). However, functional connectivity between the hippocampus and other brain regions remains unclear in MCI. Furthermore, the longitudinal changes of the hippocampal connectivity have not been reported. In the study, resting state functional MRI (fMRI) was used to examine changes in hippocampal connectivity comparing 14 patients and 14 healthy age-matched controls. We found that functional connectivity between the hippocampus and a set of regions was disrupted in MCI, these regions are: the right frontal lobe, the bilateral temporal lobe and the right insular. While, the left posterior cingulate cortex, precuneus, hippocampus, caudate and right occipital gyrus showed increased connectivity to the hippocampus in MCI. Additionally, we traced the seven MCI patients and compared the hippocampal connectivity in initial stage and 3 years later stage. Several regions presented decreased connectivity to the hippocampus after 3 years. Finally, the hippocampal connectivity with some regions showed significant correlation with the cognitive performance of patients. Based on these findings, the decreased hippocampal connectivity might indicate reduced integrity of hippocampal cortical memory network in MCI. In addition, the increased hippocampal connectivity suggested compensation for the loss of memory function. With the development of the disease, the hippocampal connectivity may lose some compensation and add some more disruption due to the pathological changes.

Shell Cross-linked Micelle-based Nanoreactors for the Substrate-selective Hydrolytic Kinetic Resolution of Epoxides

Journal of the American Chemical Society. Sep, 2011  |  Pubmed ID: 21846087

Shell cross-linked micelles (SCMs) containing Co(III)-salen cores were prepared from amphiphilic poly(2-oxazoline) triblock copolymers. The catalytic activity of these nanoreactors for the hydrolytic kinetic resolution of various terminal epoxides was investigated. The SCM catalysts showed high catalytic efficiency and, more significantly, substrate selectivity based on the hydrophobic nature of the epoxide. Moreover, because of the nanoscale particle size and the high stability, the catalyst could be recovered easily by ultrafiltration and reused with high activity for eight cycles.

Sterol Regulatory Element Binding Protein-1 (SREBP1) Activation in Motor Neurons in Excitotoxicity and Amyotrophic Lateral Sclerosis (ALS): Indip, a Potential Therapeutic Peptide

Biochemical and Biophysical Research Communications. Sep, 2011  |  Pubmed ID: 21871872

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease of motor neurons in which glutamatergic excitotoxicity may participate. A recently characterized downstream effector of glutamatergic excitotoxicity is the activation of the lipid transcription factor sterol regulatory element binding protein-1 (SREBP1). Here we report that in spinal cord tissues of transgenic mouse model, G93A, as well as post-mortem spinal cord specimens of human familial and sporadic ALS, significant activation of SREBP1 following drastic degradation of ER membrane resident protein Insig-1. A TAT-fused short peptide (Indip) to prevent Insig-1 degradation and subsequent SREBP1 activation significantly protected cultured spinal cord neurons against glutamate-induced excitotoxicity. Indip or other SREBP1-pathway modulating compounds may prove beneficial in ALS.

[The Prognostic Value of N-terminal Pro-B-type Natriuretic Peptide in Patients with Severe Sepsis and Septic Shock]

Zhongguo Wei Zhong Bing Ji Jiu Yi Xue = Chinese Critical Care Medicine = Zhongguo Weizhongbing Jijiuyixue. Aug, 2011  |  Pubmed ID: 21878169

To evaluate the prognostic value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with severe sepsis and septic shock.

Upregulation of Cellular Bcl-2 by the KSHV Encoded RTA Promotes Virion Production

PloS One. 2011  |  Pubmed ID: 21901143

Apoptosis of virus infected cells can restrict or dampen full blown virus propagation and this can serve as a protective mechanism against virus infection. Consequently, viruses can also delay programmed cell death by enhancing the expression of anti-apoptotic proteins. Human Bcl-2 is expressed on the surface of the mitochondrial membrane and functions as the regulator of the delicate balance between cell survival and apoptosis. In this report, we showed that the replication and transcription activator (RTA) encoded by KSHV ORF 50, a key regulator for KSHV reactivation from latent to lytic infection, upregulates the mRNA and protein levels of Bcl-2 in 293 cells, and TPA-induced KSHV-infected cells. Further analysis revealed that upregulation of the cellular Bcl-2 promoter by RTA is dose-dependent and acts through targeting of the CCN(9)GG motifs within the Bcl-2 promoter. The Bcl-2 P2 but not the P1 promoter is primarily responsive to RTA. The results of ChIP confirmed the direct interaction of RTA protein with the CCN(9)GG motifs. Knockdown of cellular Bcl-2 by lentivirus-delivered small hairpin RNA (shRNA) resulted in increased cell apoptosis and decreased virion production in KSHV-infected cells. These findings provide an insight into another mechanism by which KSHV utilizes the intrinsic apoptosis signaling pathways for prolonging the survival of lytically infected host cells to allow for maximum production of virus progeny.

Metabolomic Screening and Identification of the Bioactivation Pathways of Ritonavir

Chemical Research in Toxicology. Dec, 2011  |  Pubmed ID: 22040299

Ritonavir-boosted protease inhibitor regimens are widely used for HIV chemotherapy. However, ritonavir causes multiple side effects, and the mechanisms are not fully understood. The current study was designed to explore the metabolic pathways of ritonavir that may be related to its toxicity. Metabolomic analysis screened out 26 ritonavir metabolites in mice, and half of them are novel. These novel ritonavir metabolites include two glycine conjugated, two N-acetylcysteine conjugated, and three ring-open products. Accompanied with the generation of ritonavir ring-open metabolites, the formation of methanethioamide and 2-methylpropanethioamide were expected. Upon the basis of the structures of these novel metabolites, five bioactivation pathways are proposed, which may be associated with sulfation and epoxidation. By using Cyp3a-null mice, we confirmed that CYP3A is involved in four pathways of RTV bioactivation. In addition, all these five bioactivation pathways were recapitulated in the incubation of ritonavir in human liver microsomes. Further studies are suggested to determine the role of CYP3A and these bioactivation pathways in ritonavir toxicity.

Single Molecule Analysis of Replicated DNA Reveals the Usage of Multiple KSHV Genome Regions for Latent Replication

PLoS Pathogens. Nov, 2011  |  Pubmed ID: 22072974

Kaposi's sarcoma associated herpesvirus (KSHV), an etiologic agent of Kaposi's sarcoma, Body Cavity Based Lymphoma and Multicentric Castleman's Disease, establishes lifelong latency in infected cells. The KSHV genome tethers to the host chromosome with the help of a latency associated nuclear antigen (LANA). Additionally, LANA supports replication of the latent origins within the terminal repeats by recruiting cellular factors. Our previous studies identified and characterized another latent origin, which supported the replication of plasmids ex-vivo without LANA expression in trans. Therefore identification of an additional origin site prompted us to analyze the entire KSHV genome for replication initiation sites using single molecule analysis of replicated DNA (SMARD). Our results showed that replication of DNA can initiate throughout the KSHV genome and the usage of these regions is not conserved in two different KSHV strains investigated. SMARD also showed that the utilization of multiple replication initiation sites occurs across large regions of the genome rather than a specified sequence. The replication origin of the terminal repeats showed only a slight preference for their usage indicating that LANA dependent origin at the terminal repeats (TR) plays only a limited role in genome duplication. Furthermore, we performed chromatin immunoprecipitation for ORC2 and MCM3, which are part of the pre-replication initiation complex to determine the genomic sites where these proteins accumulate, to provide further characterization of potential replication initiation sites on the KSHV genome. The ChIP data confirmed accumulation of these pre-RC proteins at multiple genomic sites in a cell cycle dependent manner. Our data also show that both the frequency and the sites of replication initiation vary within the two KSHV genomes studied here, suggesting that initiation of replication is likely to be affected by the genomic context rather than the DNA sequences.

Treatment of Primary Isolated Extramedullary Plasmacytoma of Esophagus With Endoscopic Submucosal Dissection

Clinical Gastroenterology and Hepatology : the Official Clinical Practice Journal of the American Gastroenterological Association. Nov, 2011  |  Pubmed ID: 22079849

Slice Orientation and Muscarinic Acetylcholine Receptor Activation Determine the Involvement of N-methyl D-aspartate Receptor Subunit GluN2B in Hippocampal Area CA1 Long-term Depression

Molecular Brain. 2011  |  Pubmed ID: 22082088

The contribution of different GluN2 subunits of the N-methyl D-aspartate (NMDA) receptor to the induction of bidirectional hippocampal synaptic plasticity is a controversial topic. As both supporting and refuting evidence for the hypothesis of subunit specialization in opposing directions of plasticity has accumulated since it was first proposed a few years ago, we hypothesize that differences in experimental conditions may have in part contributed to some of the inconsistent results from these studies. Here we investigate the controversial hypothesis that long-term depression (LTD) is preferentially induced by GluN2B-containing NMDA receptors in area CA1 of hippocampal slices.

Prevalence of Antibodies Against Enterovirus 71 in Children from Lu'an City in Central China

Japanese Journal of Infectious Diseases. 2011  |  Pubmed ID: 22116336

We performed preepidemic and postepidemic serologic surveys to elucidate the rate of enterovirus 71 (EV71) infection in Lu'an City, Anhui Province, Central China. For the preepidemic study, a total of 472 healthy infants and children (age range, neonates to 15 years) were randomly selected before the 2008 outbreak of EV71 in the region. Blood samples were collected and tested for neutralizing antibodies (NAbs) against EV71 by performing a microneutralization assay. The results of preepidemic serological survey showed that 43.2% (204/472) of the tested samples yielded positive results for NAbs against EV71. The seropositivity rates were 29.6% (93/314) in children who were 0-7 years of age and 74.6% (59/79) in children who were 12-15 years of age. The overall geometric mean titer was 18.1, and the highest antibody titers were detected in children who were 5-7 years of age; this suggests that this group was frequently exposed to EV71 infection. For the postepidemic study, 83 serum samples were collected from healthy children ≤15 years of age in 2010. The seropositivity rate of EV71 NAbs increased in this young population after the 2008 outbreak, especially in 2- to 11-year-old children. This report shows that EV71 was spreading in Lu'an City before the 2008 outbreak, and children under 7 years of age were the main susceptible population.

Effects of Pb on the Oxidative Stress and Antioxidant Response in a Pb Bioaccumulator Plant Vallisneria Natans

Ecotoxicology and Environmental Safety. Dec, 2011  |  Pubmed ID: 22138147

The effects of Pb on photosynthetic pigments, oxidative stress and antioxidant response were assayed using biochemical and histochemical methods in leaves of Vallisneria natans (Lour.) Hara treated with 0-100μM Pb(2+) for 0-6d. The Pb content increased with the increase of exposure duration and a highest Pb uptake value (about 9.4mg Pbg(-1) dry weight) was obtained at 6d. Pb induced the accumulation of H(2)O(2) and O(2)(-). The increase of malondialdehyde content and the decrease of total chlorophyll and carotenoids were detected in V. natans under Pb stress. Activities of NAD(P)H oxidase, guaiacol peroxidase, glutathione reductase and ascorbate peroxidase increased at 75μM Pb(2+) for 2-6 days, while activities of superoxide dismutase and catalase and the content of ascorbic acid increased within two days in plants exposed to 75μM Pb(2+) and decreased thereafter. The Pb uptake and accumulation mechanism were discussed.

Histone Deacetylase Inhibitors Prevent the Degradation and Restore the Activity of Glucocerebrosidase in Gaucher Disease

Proceedings of the National Academy of Sciences of the United States of America. Dec, 2011  |  Pubmed ID: 22160715

Gaucher disease (GD) is caused by a spectrum of genetic mutations within the gene encoding the lysosomal enzyme glucocerebrosidase (GCase). These mutations often lead to misfolded proteins that are recognized by the unfolded protein response system and are degraded through the ubiquitin-proteasome pathway. Modulating this pathway with histone deacetylase inhibitors (HDACis) has been shown to improve protein stability in other disease settings. To identify the mechanisms involved in the regulation of GCase and determine the effects of HDACis on protein stability, we investigated the most prevalent mutations for nonneuronopathic (N370S) and neuronopathic (L444P) GD in cultured fibroblasts derived from GD patients and HeLa cells transfected with these mutations. The half-lives of mutant GCase proteins correspond to decreases in protein levels and enzymatic activity. GCase was found to bind to Hsp70, which directed the protein to TCP1 for proper folding, and to Hsp90, which directed the protein to the ubiquitin-proteasome pathway. Using a known HDACi (SAHA) and a unique small-molecule HDACi (LB-205), GCase levels increased rescuing enzymatic activity in mutant cells. The increase in the quantity of protein can be attributed to increases in protein half-life that correspond primarily with a decrease in degradation rather than an increase in chaperoned folding. HDACis reduce binding to Hsp90 and prevent subsequent ubiquitination and proteasomal degradation without affecting binding to Hsp70 or TCP1. These findings provide insight into the pathogenesis of GD and indicate a potent therapeutic potential of HDAC inhibitors for the treatment of GD and other human protein misfolding disorders.

Epstein-Barr Virus Nuclear Antigen 3C Stabilizes Gemin3 to Block P53-mediated Apoptosis

PLoS Pathogens. Dec, 2011  |  Pubmed ID: 22174681

The Epstein-Barr nuclear antigen 3C (EBNA3C), one of the essential latent antigens for Epstein-Barr virus (EBV)-induced immortalization of primary human B lymphocytes in vitro, has been implicated in regulating cell proliferation and anti-apoptosis via interaction with several cellular and viral factors. Gemin3 (also named DDX20 or DP103) is a member of DEAD RNA helicase family which exhibits diverse cellular functions including DNA transcription, recombination and repair, and RNA metabolism. Gemin3 was initially identified as a binding partner to EBNA2 and EBNA3C. However, the mechanism by which EBNA3C regulates Gemin3 function remains unclear. Here, we report that EBNA3C directly interacts with Gemin3 through its C-terminal domains. This interaction results in increased stability of Gemin3 and its accumulation in both B lymphoma cells and EBV transformed lymphoblastoid cell lines (LCLs). Moreover, EBNA3C promotes formation of a complex with p53 and Gemin3 which blocks the DNA-binding affinity of p53. Small hairpin RNA based knockdown of Gemin3 in B lymphoma or LCL cells remarkably attenuates the ability of EBNA3C to inhibit the transcription activity of p53 on its downstream genes p21 and Bax, as well as apoptosis. These findings provide the first evidence that Gemin3 may be a common target of oncogenic viruses for driving cell proliferation and anti-apoptotic activities.

Application of Subproteomics in the Characterization of Gram-positive Bacteria

Journal of Proteomics. Dec, 2011  |  Pubmed ID: 22240296

Gram-positive bacteria cause a series of diseases in human, animals and plants. There has been increasing interest in efforts to investigate pathogenesis of bacteria using multiple "omic" strategies including proteomics. Proteins in different cell fractions of bacteria may play different vital roles in various physiological processes, such as adhesion, invasion, internalization, sensing, respiration, oxidative stress protection and pathogenicity. Subproteomics specifically focuses on the pre-fractionated cellular proteins and thus may be able to characterize more low-abundance molecules that are usually overlooked by the traditional whole-cell proteomics, providing comprehensive information for further investigations. This review intends to outline the current progress, challenges and future development of subproteomics in the characterization of Gram-positive bacteria. This article is part of a Special Issue entitled: Clinical Proteomics.

[Clinical Efficacy of Desmopressin in the Treatment of Mild Hemophilia A in Children]

Zhongguo Dang Dai Er Ke Za Zhi = Chinese Journal of Contemporary Pediatrics. Sep, 2011  |  Pubmed ID: 21924018

To study the effects of desmopressin (DDAVP) on coagulation factor Ⅷ (FⅧ) and activated partial thromboplastin time (APTT) in children with mild hemophilia A.

Fouling Control Mechanisms of Demineralized Water Backwash: Reduction of Charge Screening and Calcium Bridging Effects

Water Research. Dec, 2011  |  Pubmed ID: 22014561

This paper investigates the impact of the ionic environment on the charge of colloidal natural organic matter (NOM) and ultrafiltration (UF) membranes (charge screening effect) and the calcium adsorption/bridging on new and fouled membranes (calcium bridging effect) by measuring the zeta potentials of membranes and colloidal NOM. Fouling experiments were conducted with natural water to determine whether the reduction of the charge screening effect and/or calcium bridging effect by backwashing with demineralized water can explain the observed reduction in fouling. Results show that the charge of both membranes and NOM, as measured by the zeta potential, became more negative at a lower pH and a lower concentration of electrolytes, in particular, divalent electrolytes. In addition, calcium also adsorbed onto the membranes, and consequently bridged colloidal NOM and membranes via binding with functional groups. The charge screening effect could be eliminated by flushing NOM and membranes with demineralized water, since a cation-free environment was established. However, only a limited amount of the calcium bridging connection was removed with demineralized water backwashes, so the calcium bridging effect mostly could not be eliminated. As demineralized water backwash was found to be effective in fouling control, it can be concluded that the reduction of the charge screening is the dominant mechanism for this.

Focal Pontine Lesions Provide Evidence That Intrinsic Functional Connectivity Reflects Polysynaptic Anatomical Pathways

The Journal of Neuroscience : the Official Journal of the Society for Neuroscience. Oct, 2011  |  Pubmed ID: 22016540

Intrinsic functional connectivity detected by functional MRI (fMRI) provides a useful but indirect approach to study the organization of human brain systems. An unresolved question is whether functional connectivity measured by resting-state fMRI reflects anatomical connections. In this study, we used the well-characterized anatomy of cerebrocerebellar circuits to directly test whether intrinsic functional connectivity is associated with an anatomic pathway. Eleven first-episode stroke patients were scanned five times during a period of 6 months, and 11 healthy control subjects were scanned three times within 1 month. In patients with right pontine strokes, the functional connectivity between the right motor cortex and the left cerebellum was selectively reduced. This connectivity pattern was reversed in patients with left pontine strokes. Although factors beyond anatomical connectivity contribute to fMRI measures of functional correlation, these results provide direct evidence that functional connectivity depends on intact connections within a specific polysynaptic pathway.

[Relationship Between Computed Tomography Perfusion Imaging and Prognosis in Hyperacute Cerebral Infarction]

Zhonghua Yi Xue Za Zhi. Dec, 2011  |  Pubmed ID: 22333200

To explore the diagnostic valves of computed tomography perfusion imaging (CTP) in hyperacute cerebral infarction patients and examine the correlation of time period from symptom onset to examination and CTP parameters.

Antidepressant-like Effects of the Saponins Extracted from Chaihu-jia-longgu-muli-tang in a Rat Unpredictable Chronic Mild Stress Model

Fitoterapia. Jan, 2012  |  Pubmed ID: 22019334

Chaihu-jia-longgu-muli-tang (CLM) has been used for treating depressive disorders for thousands of years in China. In the present study, we investigated the antidepressant-like effect of the saponins extracted from CLM (SCLM) in rats subjected to unpredictable chronic mild stress (UCMS). The ameliorative effect of SCLM on symptom of depression through behavior tests including: sucrose preference test, open-field test and forced-swimming test was investigated. In addition, high performance liquid chromatography with electrochemical detection (HPLC-ECD), immunohistochemical staining analysis and RT-PCR were applied to explore the mechanisms underlying the antidepressant-like effects of SCLM. It was observed that administration of SCLM (70, 140 mg/kg) reversed the depressive-like behaviors, restored the reduction in the levels of monoamine neurotransmitters and up-regulated the expression of brain-derived neurotrophic factor (BDNF) in UCMS-treated rats. These findings confirmed the antidepressant-like effects of SCLM in UCMS model of rats.

Combined Effects of FLT3 and NF-κB Selective Inhibitors on Acute Myeloid Leukemia in Vivo

Journal of Biochemical and Molecular Toxicology. Jan, 2012  |  Pubmed ID: 21928377

FMS-like tyrosine kinase 3 (FLT3) is an independent poor prognostic marker of acute myeloid leukemia (AML), and strategies that specifically target FLT3 are therefore of substantial interest. However, previous studies with FLT3 inhibitors as single agents in patients with AML showed few clinical responses. In the present study, combined effects of FLT3 selective inhibitor (SC-203048) and NF-κB selective inhibitor (Parthenolide, PTL) on AML xenograft tumor growth in vivo were examined, and the possible antitumor mechanisms by which SC-203048 and PTL affect AML xenograft tumor growth were also detected. Results showed that the tumor growth was strongly inhibited, and increased cell apoptosis was also observed after treatments, especially in the combination group; meanwhile, the expressions of FLT3, p65, cyclin D1, and Bc1-2 decreased significantly, and the expression of nuclear Silencing mediator for retinoic acid and thyroid hormone receptors (SMRT) increased notably. All results indicate that synergism exists between FLT3 and NF-κB inhibitors, and inhibitors combination treatment may be a potential strategy for AML. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:35-43 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20411.

CPY3A4-mediated Lopinavir Bioactivation and Its Inhibition by Ritonavir

Drug Metabolism and Disposition: the Biological Fate of Chemicals. Jan, 2012  |  Pubmed ID: 21953914

The combination of lopinavir (LPV) and ritonavir (RTV) is one of the preferred regimens for the treatment of HIV infection with confirmed efficacy and relatively low toxicity. LPV alone suffers the poor bioavailability due to its rapid and extensive metabolism. RTV boosts the plasma concentration of LPV by suppressing its metabolism and thus increasing LPV efficacy. In the current study, we found that RTV also inhibits LPV bioactivation. LPV bioactivation was investigated in human liver microsomes and cDNA-expressed human cytochromes P450. Twelve GSH-trapped reactive metabolites of LPV were identified by using a metabolomic approach. Semicarbazide-trapped reactive metabolites of LPV were also detected. RTV effectively suppressed all pathways of LPV bioactivation via CYP3A4 inhibition. Our data together with previous reports suggest that LPV plus RTV is an ideal combination because RTV not only boosts LPV plasma concentration, but it decreases LPV bioactivation.

Protective Effects of Ulinastatin on Acute Liver Failure Induced by Lipopolysaccharide/d: -galactosamine

Digestive Diseases and Sciences. Feb, 2012  |  Pubmed ID: 22001939

Although treatment of acute liver failure has been improved significantly recently, the survival rate of acute liver failure is only 5-20%. Therefore, prevention and treatment of acute liver failure are still urgent issues in the field of liver disease.

Promoting Nerve Cell Functions on Hydrogels Grafted with Poly(l-lysine)

Biomacromolecules. Feb, 2012  |  Pubmed ID: 22251248

We present a novel photopolymerizable poly(l-lysine) (PLL) and use it to modify polyethylene glycol diacrylate (PEGDA) hydrogels for creating a better, permissive nerve cell niche. Compared with their neutral counterparts, these PLL-grafted hydrogels greatly enhance pheochromocytoma (PC12) cell survival in encapsulation, proliferation, and neurite growth and also promote neural progenitor cell proliferation and differentiation capacity, represented by percentages of both differentiated neurons and astrocytes. The role of efficiently controlled substrate stiffness in regulating nerve cell behavior is also investigated and a polymerizable cationic small molecule, [2-(methacryloyloxy)ethyl]-trimethylammonium chloride (MTAC), is used to compare with this newly developed PLL. The results indicate that these PLL-grafted hydrogels are promising biomaterials for nerve repair and regeneration.

The RBP-Jκ Binding Sites Within the RTA Promoter Regulate KSHV Latent Infection and Cell Proliferation

PLoS Pathogens. Jan, 2012  |  Pubmed ID: 22253595

Kaposi's sarcoma-associated herpesvirus (KSHV) is tightly linked to at least two lymphoproliferative disorders, primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). However, the development of KSHV-mediated lymphoproliferative disease is not fully understood. Here, we generated two recombinant KSHV viruses deleted for the first RBP-Jκ binding site (RTA(1st)) and all three RBP-Jκ binding sites (RTA(all)) within the RTA promoter. Our results showed that RTA(1st) and RTA(all) recombinant viruses possess increased viral latency and a decreased capability for lytic replication in HEK 293 cells, enhancing colony formation and proliferation of infected cells. Furthermore, recombinant RTA(1st) and RTA(all) viruses showed greater infectivity in human peripheral blood mononuclear cells (PBMCs) relative to wt KSHV. Interestingly, KSHV BAC36 wt, RTA(1st) and RTA(all) recombinant viruses infected both T and B cells and all three viruses efficiently infected T and B cells in a time-dependent manner early after infection. Also, the capability of both RTA(1st) and RTA(all) recombinant viruses to infect CD19+ B cells was significantly enhanced. Surprisingly, RTA(1st) and RTA(all) recombinant viruses showed greater infectivity for CD3+ T cells up to 7 days. Furthermore, studies in Telomerase-immortalized human umbilical vein endothelial (TIVE) cells infected with KSHV corroborated our data that RTA(1st) and RTA(all) recombinant viruses have enhanced ability to persist in latently infected cells with increased proliferation. These recombinant viruses now provide a model to explore early stages of primary infection in human PBMCs and development of KSHV-associated lymphoproliferative diseases.

Development of Radiolabeled Compounds for Myocardial Perfusion Imaging

Current Pharmaceutical Design. Jan, 2012  |  Pubmed ID: 22272824

Coronary artery disease (CAD) is the main cause of death and remains a major health problem worldwide. Myocardial perfusion imaging is a well established noninvasive method for assessing CAD. This review summarizes the development of various radiotracers for myocardial perfusion imaging, including single photon emission computed tomography (SPECT) perfusion imaging agents and positron emission tomography (PET) perfusion imaging agents and introduces novel basic research data related to this area. In addition, the current state of the art in myocardial perfusion imaging agents and the future direction are discussed in this review.

Dosimetric Research on Intensity-modulated Arc Radiotherapy Planning for Left Breast Cancer After Breast-preservation Surgery

Medical Dosimetry : Official Journal of the American Association of Medical Dosimetrists. Jan, 2012  |  Pubmed ID: 22284640

BACKGROUND: Intensity-modulated radiotherapy (IMRT) has played an important role in breast cancer radiotherapy after breast-preservation surgery. Our aim was to study the dosimetric and implementation features/feasibility between IMRT and intensity-modulated arc radiotherapy (Varian RapidArc, Varian, Palo Alto, CA). MATERIALS AND METHODS: The forward IMRT plan (f-IMRT), the inverse IMRT, and the RapidArc plan (RA) were generated for 10 patients. Afterward, we compared the target dose distribution of the 3 plans, radiation dose on organs at risk, monitor units, and treatment time. RESULTS: All 3 plans met clinical requirements, with RA performing best in target conformity. In target homogeneity, there was no statistical significance between RA and IMRT, but both of homogeneity were less than f-IMRT's. With regard to the V(5) and V(10) of the left lung, those in RA were higher than in f-IMRT but were lower than in IMRT; for V(20) and V(30), the lowest was observed in RA; and in the V(5) and V(10) of the right lung, as well as the mean dose in normal-side breast and right lung, there was no statistically significance difference between RA and IMRT, and the lowest value was observed in f-IMRT. As for the maximum dose in the normal-side breast, the lowest value was observed in RA. Regarding monitor units (MUs), those in RA were higher than in f-IMRT but were lower than in IMRT. Treatment time of RA was 84.6% and 88.23% shorter than f-IMRT and IMRT, respectively, on average. CONCLUSIONS: Compared with f-IMRT and IMRT, RA performed better in target conformity and can reduce high-dose volume in the heart and left lung-which are related to complications-significantly shortening treatment time as well. Compared with IMRT, RA can also significantly reduce low-dose volume and MUs of the afflicted lung.

Efficacy of Intraductal Ultrasonography in the Diagnosis of Non-opaque Choledocholith

World Journal of Gastroenterology : WJG. Jan, 2012  |  Pubmed ID: 22294831

To evaluate the efficacy of intraductal ultrasonography (IDUS) in the diagnosis of non-opaque, common bile duct stones.

Within-limb Somatotopic Organization in Human SI and Parietal Operculum for the Leg: An FMRI Study

Brain Research. Jan, 2012  |  Pubmed ID: 22305143

Somatotopic organizations in human somatosensory cortex (SI and SII) for scattered portions of the leg have not been systematically observed with functional magnetic resonance imaging (fMRI). In this research we compared functional representations in the contralateral SI and bilateral parietal operculum (that contained subregions OP1, 3-4 of SII and OP2) of four acupoints in right leg in proximal-distal and medial-lateral arrangement. The results were: (1) somatotopy of SI demonstrated a lateral-to-medial and inferior-to-superior pattern when acupoints were shifting from proximal to distal or from medial to lateral; (2) the contralateral OP1 also showed a clear somatotopic organization for the four separated leg portions, and the ipsilateral OP1 showed a similar pattern to the contralateral OP1, thus arrangements of responses in the two areas were mirror-symmetric against y-axis; (3) the contralateral OP2 showed a somatotopic organization when acupoints shifting from proximal to distal, while the contralateral OP3 presented a trend of somatotopy opposite to that of the contralateral OP1. These results first show definite within-leg somatotopy of human SI for scattered leg portions in medial-lateral arrangement using fMRI. Within-limb somatotopic organization of OP1 for leg portions arranging from proximal to distal as well as from medial to lateral, and somatotopy of OP2 for leg portions arranging from proximal to distal, are also shown for the first time. Our results also reinforce the proposal of a somatotopic map existing in human OP3, and indicating a fourth somatotopic map in OP2 in human parietal operculum, which suggests that OP 2 is not just a vestibular area. In addition, separable activations in somatosensory cortex induced by adjacent acupoints should play a fundamental role in acupoint-specific effects in the brain.

Big Roles for Small RNAs in Polyploidy, Hybrid Vigor, and Hybrid Incompatibility

Current Opinion in Plant Biology. Feb, 2012  |  Pubmed ID: 22326630

Small RNAs, including microRNAs (miRNAs), small interfering RNAs (siRNAs), and trans-acting siRNAs (ta-siRNAs), mediate gene expression and epigenetic regulation. While siRNAs are highly diverged, miRNAs and ta-siRNAs are generally conserved but many are differentially expressed between related species and in interspecific hybrids and allopolyploids. On one hand, combination of diverged maternal and paternal siRNAs in the same nucleus may exert cis-acting and trans-acting effects on transposable elements (TEs) and TE-associated genes, leading to genomic instability and endosperm and embryo failures, constituting a bottleneck for the evolution of hybrids and polyploids. On the other hand, cis and trans-acting small RNAs induce quantitative and qualitative changes in epigenetic regulation, leading to morphological variation and hybrid vigor in F1 hybrids and stable allopolyploids as well as transgressive phenotypes in the progeny, increasing a potential for adaptive evolution.

Lubricated Biodegradable Polymer Networks for Regulating Nerve Cell Behavior and Fabricating Nerve Conduits with a Compositional Gradient

Biomacromolecules. Feb, 2012  |  Pubmed ID: 22206477

We present a method of tuning surface chemistry and nerve cell behavior by photo-cross-linking methoxy poly(ethylene glycol) monoacrylate (mPEGA) with hydrophobic, semicrystalline poly(ε-caprolactone) diacrylate (PCLDA) at various weight compositions of mPEGA (ϕ(m)) from 2 to 30%. Improved surface wettability is achieved with corresponding decreases in friction, water contact angle, and capability of adsorbing proteins from cell culture media because of repulsive PEG chains tethered in the network. The responses of rat Schwann cell precursor line (SpL201), rat pheochromocytoma (PC12), and E14 mouse neural progenitor cells (NPCs) to the modified surfaces are evaluated. Nonmonotonic or parabolic dependence of cell attachment, spreading, proliferation, and differentiation on ϕ(m) is identified for these cell types with maximal values at ϕ(m) of 5-7%. In addition, NPCs demonstrate enhanced neuronal differentiated lineages on the mPEGA/PCLDA network at ϕ(m) of 5% with intermediate wettability and surface energy. This approach lays the foundation for fabricating heterogeneous nerve conduits with a compositional gradient along the wall thickness, which are able to promote nerve cell functions within the conduit while inhibiting cell attachment on the outer wall to prevent potential fibrous tissue formation following implantation.

Antidepressant-like Effect of Magnolol on BDNF Up-regulation and Serotonergic System Activity in Unpredictable Chronic Mild Stress Treated Rats

Phytotherapy Research : PTR. Jan, 2012  |  Pubmed ID: 22223265

Magnolol is the main constituent identified in the barks of Magnolia officinalis, which has been used for the treatment of mental disorders including depression in China. In this study, we investigated the antidepressant-like effect of magnolol, and its possible mechanisms in rats subjected to unpredictable chronic mild stress (UCMS). High performance liquid chromatography with electrochemical detection (HPLC-ECD) and immunohistochemical staining analysis were applied to explore the mechanisms underlying the antidepressant-like effect of magnolol. Magnolol (20, 40 mg/kg) significantly reversed UCMS-induced reduction in sucrose consumption and deficiency in locomotor activity. In addition, it was observed that administration of magnolol (20, 40 mg/kg) restored brain-derived neurotrophic factor (BDNF) expression, and normalized the serotonergic system changes in the UCMS-treated rats. These results confirmed the antidepressant-like effect of magnolol, which might be based primarily on its ability to increase the BDNF expression and enhance the activity of the serotonergic system in rat brains. Copyright © 2012 John Wiley & Sons, Ltd.

Effect of RNAi-induced Down Regulation of Nuclear Factor Kappa-B P65 on Acute Monocytic Leukemia THP-1 Cells in Vitro and Vivo

Molecular and Cellular Biochemistry. Jan, 2012  |  Pubmed ID: 21901538

NF-κB p65 is found constitutively active in acute monocytic leukemia, and has been considered an important factor for poor prognosis. Therefore, develop specifically target p65 inhibitors will be substantial interest. Until now, although several p65 inhibitors are currently in preclinical and clinical development, none of them are targeting. In this study, siRNA targeting p65 was introduced into the acute monocytic leukemia cell line THP-1 and THP-1 xenograft tumors in nude mice, and then, we measured p65 mRNA and protein levels by real-time RT-PCR and Western blotting, and levels of related protein cyclin D1, Bc1-2, and SMRT by Western blotting. We also investigated the cell cycle and apoptosis via FCM, and cell proliferation by Cell Counting Kit-8 assay. We found that p65 siRNA could effectively reduce the p65 mRNA and protein expression, arrest cells in G0/G1 phase, inhibit the proliferation and increase the apoptosis of THP-1 cells, and intratumoral injection of p65 siRNA could suppress tumor growth in nude mice. We also found that when down regulation of p65, the expression of cyclin D1 and Bc1-2 decreased, and the expression of SMRT increased in vitro and vivo. All these findings suggest that NF-κB p65 maybe an attractive candidate for the therapeutic targeting of acute monocytic leukemia.

Roles of Target Site Location and Sequence Complementarity in Trans-acting SiRNA Formation in Arabidopsis

The Plant Journal : for Cell and Molecular Biology. Jan, 2012  |  Pubmed ID: 21910773

In plants, many mRNAs and non-coding RNAs are cleaved by RNA-induced silencing complexes. After cleavage, only a limited number of RNAs are processed into trans-acting siRNAs (tasiRNAs). One reason is that 22 nt small RNAs, but not the more common 21 nt small RNAs, can efficiently trigger tasiRNA formation. The characteristics of the target transcripts may also affect tasiRNA production. Here we report the effects of target site location and sequence complementarity on tasiRNA formation. A synthetic sequence that included a miR173 target site and two siRNAs targeting an endogenous mRNA encoding PHYTOENE DESATURASE3 was introduced into a protein-coding (GFP) gene in the coding region or 3' UTR. tasiRNAs were generated in the transgenic seedlings, and the PDS3 mRNA level was reduced, leading to a photobleaching phenotype. It was found that tasiRNAs were most efficiently produced when the miR173 target site was placed immediately after the stop codon. Introducing premature stop codons caused a dramatic reduction of tasiRNAs and over-accumulation of 3' cleavage products, suggesting positive effects of translation on processing the 3' cleavage products into tasiRNAs. By systematically mutating the miR173 target site, we found that perfect complementarity between the 3' end of miR173 and the 5' end of the target sequence was crucial. Mismatches at that position abolished tasiRNA formation, but mismatches at the 5' end of miR173 had less effect. These data suggest important roles for translation and specific sequence complementarity in tasiRNA formation, providing new insights into tasiRNA biogenesis as well as a strategy for improving the efficiency of RNA interference (RNAi) using tasiRNAs.

In Vivo Tumor Suppression Efficacy of Mesoporous Silica Nanoparticles-based Drug-delivery System: Enhanced Efficacy by Folate Modification

Nanomedicine : Nanotechnology, Biology, and Medicine. Feb, 2012  |  Pubmed ID: 21703996

Mesoporous silica nanoparticles (MSNs) have proven to be promising vehicles for drug delivery. However, despite the potential, few studies have extended the success of in vitro studies to animal settings. In this article, we report the efficacy of MSNs using two different human pancreatic cancer xenografts on different mouse species. Significant tumor-suppression effects were achieved with camptothecin-loaded MSNs. Dramatic improvement of the potency of tumor suppression was obtained by surface modifying MSNs with folic acid. Dose-dependent tumor suppression was observed, establishing 0.5 mg of CPT-loaded MSNs per mouse as a minimum dose sufficient for achieving complete tumor growth inhibition. Renal excretion of MSNs was also confirmed with transmission electron microscopy (TEM) imaging. These findings highlight attractive features (biocompatibility, renal clearance and high efficacy for delivering anticancer drugs) of MSNs as a drug-delivery system. FROM THE CLINICAL EDITOR: In this study, mesoporous silica nanoparticles are used as chemotherapy delivering agents in two different human pancreatic cancer xenografts and different mouse species. Significant tumor-suppression effects, biocompatibility and efficient renal clearance are demonstrated.

Lipiodol: a Potential Direct Surrogate for Cone-beam Computed Tomography Image Guidance in Radiotherapy of Liver Tumor

International Journal of Radiation Oncology, Biology, Physics. Feb, 2012  |  Pubmed ID: 21377291

To investigate the feasibility of using lipiodol as a direct surrogate for target localization using cone-beam CT (CBCT) image guidance in radiotherapy (RT) of patients with unresectable liver tumors after transarterial chemoembolization.