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Find video protocols related to scientific articles indexed in Pubmed.
Combivena gen.n (Hymenoptera: Ichneumonidae: Acaenitinae) from China.
J. Insect Sci.
PUBLISHED: 10-15-2014
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Combivena Sheng & Sun, gen.n. and Combivena sulcata Sheng & Sun, sp.n. belonging to Acaenitinae of family Ichneumonidae (Hymenoptera), collected from Qinghai Province, China, are described and illustrated.
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The novel Aryl hydrocarbon receptor inhibitor biseugenol inhibits gastric tumor growth and peritoneal dissemination.
Oncotarget
PUBLISHED: 09-17-2014
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Biseugenol (Eug) is known to antiproliferative of cancer cells; however, to date, the antiperitoneal dissemination effects have not been studied in any mouse cancer model. In this study, Aryl hydrocarbon receptor (AhR) expression was associated with lymph node and distant metastasis in patients with gastric cancer and was correlated with clinicolpathological pattern. We evaluated the antiperitoneal dissemination potential of knockdown AhR and Biseugenol in cancer mouse model and assessed mesenchymal characteristics. Our results demonstrate that tumor growth, peritoneal dissemination and peritoneum or organ metastasis implanted MKN45 cells were significantly decreased in shAhR and Biseugenol-treated mice and that endoplasmic reticulum (ER) stress was caused. Biseugenol-exposure tumors showed acquired epithelial features such as phosphorylation of E-cadherin, cytokeratin-18 and loss mesenchymal signature Snail, but not vimentin regulation. Snail expression, through AhR activation, is an epithelial-to-mesenchymal transition (EMT) determinant. Moreover, Biseugenol enhanced Calpain-10 (Calp-10) and AhR interaction results in Snail downregulation. The effect of shCalpain-10 in cancer cells was associated with inactivation of AhR/Snail promoter binding activity. Inhibition of Calpain-10 in gastric cancer cells by short hairpin RNA or pharmacological inhibitor was found to effectively reduced growth ability and vessel density in vivo. Importantly, knockdown of AhR completed abrogated peritoneal dissemination. Herein, Biseugenol targeting ER stress provokes Calpain-10 activity, sequentially induces reversal of EMT and apoptosis via AhR may involve the paralleling processes. Taken together, these data suggest that Calpain-10 activation and AhR inhibition by Biseugenol impedes both gastric tumor growth and peritoneal dissemination by inducing ER stress and inhibiting EMT.
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Striking effect of intra- versus intermolecular hydrogen bonding on zwitterions: physical and electronic properties.
J. Am. Chem. Soc.
PUBLISHED: 08-07-2014
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We report the synthesis, characterization, and application of novel zwitterions. The zwitterionic structures consist of a positively charged cyanine and negatively charged dienolate moieties, confirmed by experimental observations and theoretical calculations. Single crystal X-ray studies revealed that BIT-(NPh)2 is a coplanar molecule that forms 1-D chains via ?-? interactions. In contrast, BIT-(NHexyl)2 is a twisted molecule with a dihedral angle of 78° between the charged planes. In charge transport studies, thin films of the flat zwitterion show semiconducting properties, with a hole mobility of 2.1 × 10(-4) cm(2) V(-1) s(-1) while the twisted zwitterion is a high resistivity insulator.
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Pressure-stabilized lithium caesides with caesium anions beyond the -1 state.
Nat Commun
PUBLISHED: 07-31-2014
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Main group elements usually assume a typical oxidation state while forming compounds with other species. Group I elements are usually in the +1 state in inorganic materials. Our recent work reveals that pressure may make the inner shell 5p electrons of Cs reactive, causing Cs to expand beyond the +1 oxidation state. Here we predict that pressure can cause large electron transfer from light alkali metals such as Li to Cs, causing Cs to become anionic with a formal charge much beyond -1. Although Li and Cs only form alloys at ambient conditions, we demonstrate that these metals form stable intermetallic LinCs (n=1-5) compounds under pressures higher than 100?GPa. Once formed, these compounds exhibit interesting structural features, including capped cuboids and dimerized icosahedra. Finally, we explore the possibility of superconductivity in metastable LiCs and discuss the effect of the unusual anionic state of Cs on the transition temperature.
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Interfacial engineering of carbon nanofiber-graphene-carbon nanofiber heterojunctions in flexible lightweight electromagnetic shielding networks.
ACS Appl Mater Interfaces
PUBLISHED: 06-24-2014
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Lightweight carbon materials of effective electromagnetic interference (EMI) shielding have attracted increasing interest because of rapid development of smart communication devices. To meet the requirement in portable electronic devices, flexible shielding materials with ultrathin characteristic have been pursued for this purpose. In this work, we demonstrated a facile strategy for scalable fabrication of flexible all-carbon networks, where the insulting polymeric frames and interfaces have been well eliminated. Microscopically, a novel carbon nanofiber-graphene nanosheet-carbon nanofiber (CNF-GN-CNF) heterojunction, which plays the dominant role as the interfacial modifier, has been observed in the as-fabricated networks. With the presence of CNF-GN-CNF heterojunctions, the all-carbon networks exhibit much increased electrical properties, resulting in the great enhancement of EMI shielding performance. The related mechanism for engineering the CNF interfaces based on the CNF-GN-CNF heterojunctions has been discussed. Implication of the results suggests that the lightweight all-carbon networks, whose thickness and density are much smaller than other graphene/polymer composites, present more promising potential as thin shielding materials in flexible portable electronics.
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Transcriptome of the inflorescence meristems of the biofuel plant Jatropha curcas treated with cytokinin.
BMC Genomics
PUBLISHED: 06-21-2014
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Jatropha curcas, whose seed content is approximately 30-40% oil, is an ideal feedstock for producing biodiesel and bio-jet fuels. However, Jatropha plants have a low number of female flowers, which results in low seed yield that cannot meet the needs of the biofuel industry. Thus, increasing the number of female flowers is critical for the improvement of Jatropha seed yield. Our previous findings showed that cytokinin treatment can increase the flower number and female to male ratio and also induce bisexual flowers in Jatropha. The mechanisms underlying the influence of cytokinin on Jatropha flower development and sex determination, however, have not been clarified.
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Aberrant estrogen receptor alpha expression correlates with hepatocellular carcinoma metastasis and its mechanisms.
Hepatogastroenterology
PUBLISHED: 06-05-2014
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Metastasis one of the obstacles before poor prognosis of hepatocellular carcinoma (HCC) is improved. Estrogen receptor alpha (ERalpha) plays an important role in the development and progression of HCC. However, the molecular mechanism of ERalpha in mediating HCC metastasis is still unclear. The aim of the present study was to detect aberrant ERalpha expression in HCC and elucidate its possible mechanisms in HCC metastasis.
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Development of synthetic peptide-modified liposomes with LDL receptor targeting capacity and improved anticancer activity.
Mol. Pharm.
PUBLISHED: 06-03-2014
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In this study, we report an active targeting liposomal formulation directed by a novel peptide (AA13) that specifically binds to the low density lipoprotein receptor (LDLR) overexpressed on acute myeloid leukemia (AML) cells. The objectives of this study were to evaluate the in vitro and in vivo tumor drug targeting delivery of AA13-anchored liposomes on AML cells. AA13 conjugated to the distal end of DSPE-PEG2000-maleimide was incorporated into the liposomes via a postinsertion method. To study the effect of the peptide decoration and density on tumor cell targeting and internalization by AML cells (THP-1 and NB4), stealth liposomes bearing 3% (peptide/S100PC, molar ratio, LL) and 7% (peptide/S100PC, molar ratio, HL) AA13 were prepared, respectively. Higher uptake of LL (1.9- and 2.6-fold) and HL (2.3- and 3.6-fold) targeted liposomes occurred in THP-1 and NB4 cells, respectively, compared to untargeted liposomes. An LDLR inhibitor was used to confirm inhibition of the receptor-mediated cellular association of AA13 modified liposome in both cells. Daunorubicin (DNR) demonstrated a 2.2- and 3.5-fold higher cytotoxicity with the HL formulation and a 1.2- and 2.0-fold higher cytotoxicity with the LL formulation compared to the unmodified liposomal formulation in THP-1 and NB4 cells, respectively. Tumor drug accumulation of DNR-loaded HL was greater than that of the untargeted liposome in the biodistribution assay. The in vivo efficacy study in BALB/c nude mice bearing NB4 xenografts treated with DNR loaded HL also showed more tumor volume inhibition and a longer survival time compared to the untargeted formulation. In conclusion, the AA13-anchored liposomes demonstrated desirable potential as a promising vector for enhanced AML tumor drug targeting.
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Enhanced microwave absorption property of reduced graphene oxide (RGO)-MnFe2O4 nanocomposites and polyvinylidene fluoride.
ACS Appl Mater Interfaces
PUBLISHED: 05-07-2014
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MnFe2O4 nanoparticles have been synthesized on a large scale by a simple hydrothermal process in a wild condition, and the RGO/MnFe2O4 nanocomposites were also prepared under ultrasonic treatment based on the synthesized nanoparticles. The absorption properties of MnFe2O4/wax, RGO/MnFe2O4/wax and the RGO/MnFe2O4/PVDF (polyvinylidene fluoride) composites were studied; the results indicated that the RGO/MnFe2O4/PVDF composites show the most excellent wave absorption properties. The minimum reflection loss of RGO/MnFe2O4/PVDF composites with filler content of 5 wt % can reach -29.0 dB at 9.2 GHz, and the bandwidth of frequency less than -10 dB is from 8.00 to 12.88 GHz. The wave absorbing mechanism can be attributed to the dielectric loss, magnetic loss and the synergetic effect between RGO+MnFe2O4, RGO+PVDF and MnFe2O4+PVDF.
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Dynamic use of B-type natriuretic peptide-guided acute coronary syndrome therapy.
Am. J. Med. Sci.
PUBLISHED: 04-26-2014
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Very few studies have evaluated the potential of using B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) as surrogate markers to guide clinical interventional or conservative therapy decisions.
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Discovery of a novel rumen methanogen in the anaerobic fungal culture and its distribution in the rumen as revealed by real-time PCR.
BMC Microbiol.
PUBLISHED: 04-17-2014
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The novel archaea belonging to Rumen Cluster C (RCC), which may play an important role in methane production in the rumen have received increased attention. However, the present information on RCC in the rumen is limited by the unsuccessful isolation of axenic pure RCC from the rumen. In the present study, RCC grown in anaerobic fungal subcultures was identified by the molecular and culture methods.
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All-trans retinoic acid induces DU145 cell cycle arrest through Cdk5 activation.
Cell. Physiol. Biochem.
PUBLISHED: 04-14-2014
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All-trans retinoic acid (ATRA), the active form of vitamin A, plays an important role in the growth arrest of numerous types of cancer cells. It has been indicated that cyclin-dependent kinase 5 (Cdk5) activity can be affected by ATRA treatment. Our previous results demonstrate the involvement of Cdk5 in the fate of prostate cancer cells. The purpose of this study is to examine whether Cdk5 is involved in ATRA-induced growth arrest of the castration-resistant cancer cell line DU145 through up-regulating Cdk inhibitor protein, p27.
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Dopaminergic Neuron-Like Cells Derived from Bone Marrow Mesenchymal Stem Cells by Lmx1? and Neurturin Overexpression for Autologous Cytotherapy in Hemiparkinsonian Rhesus Monkeys.
Curr Stem Cell Res Ther
PUBLISHED: 04-07-2014
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Bone marrow-derived mesenchymal stem cells hold great potential for cytotherapeutics of neurodegenerative disorders, including Parkinson's disease. The neurotrophic factor neurturin can rescue dopaminergic neurons damaged during the disease process. Lmx1? can promote mesencephalic dopaminergic differentiation during embryogenesis. In this study, we tested a cytotherapeutic strategy combining NTN/Lmx1? gene therapy and cell transplantation to ameliorate disease progression in hemiparkinsonian rhesus. Rhesus BMSCs were prepared for autologous grafting by transfection with recombinant adenoviral vectors expressing secreted NTN and Lmx1?, and cultured in the presence of induce factors, particularly the Lmx1? regulatory factor sonic hedgehog, to guide dopaminergic differentiation. These induced rh-BMSCs exhibited gene/protein expression phenotypes resembling nigral dopaminergic neurons. They survived and retained dopaminergic function following stereotaxic injection into the MPTP-lesioned right-side substantia nigra as indicated by SPECT measurement of DAT activity. Injected cells preserved and supplemented the remaining endogenous population of dopamine neurons (TH-positive cell ipsilateral/contralateral ratio was 56.81% ± 7.28% vs. 3.86%±1.22% in vehicle-injected controls; p<0.05). Cell injection also partially restored motor function and reduce apomorphine-evoked rotation (p<0.05). Moreover, function recovery occurred earlier than in previous studies on injected BMSCs. Our findings demonstrate a promising strategy for restoration of PD-associated motor dysfunction by transplantation of autologous BMSCs overexpressing NTN/Lmx1?
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High pressure electrides: a predictive chemical and physical theory.
Acc. Chem. Res.
PUBLISHED: 04-05-2014
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Electrides, in which electrons occupy interstitial regions in the crystal and behave as anions, appear as new phases for many elements (and compounds) under high pressure. We propose a unified theory of high pressure electrides (HPEs) by treating electrons in the interstitial sites as filling the quantized orbitals of the interstitial space enclosed by the surrounding atom cores, generating what we call an interstitial quasi-atom, ISQ. With increasing pressure, the energies of the valence orbitals of atoms increase more significantly than the ISQ levels, due to repulsion, exclusion by the atom cores, effectively giving the valence electrons less room in which to move. At a high enough pressure, which depends on the element and its orbitals, the frontier atomic electron may become higher in energy than the ISQ, resulting in electron transfer to the interstitial space and the formation of an HPE. By using a He lattice model to compress (with minimal orbital interaction at moderate pressures between the surrounding He and the contained atoms or molecules) atoms and an interstitial space, we are able to semiquantitatively explain and predict the propensity of various elements to form HPEs. The slopes in energy of various orbitals with pressure (s > p > d) are essential for identifying trends across the entire Periodic Table. We predict that the elements forming HPEs under 500 GPa will be Li, Na (both already known to do so), Al, and, near the high end of this pressure range, Mg, Si, Tl, In, and Pb. Ferromagnetic electrides for the heavier alkali metals, suggested by Pickard and Needs, potentially compete with transformation to d-group metals.
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[Clinical application of magnetic resonance imaging in congenital anorectal malformation].
Zhonghua Er Ke Za Zhi
PUBLISHED: 04-01-2014
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To investigate the clinical value of MRI examination in congenital anorectal malformation (CARM).
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Comparative study of video-assisted thoracic surgery versus open thymectomy for thymoma in one single center.
J Thorac Dis
PUBLISHED: 03-17-2014
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Due to the popularity of video-assisted thoracic surgery (VATS) techniques in clinical, thymoma patients via VATS thymectomy are increasing rapidly. However, compared with open thymectomy, the potential superiorities and defects of VATS thymectomy remain controversial.
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Carcinogenic and mutagenic potencies for different PAHs sources in coastal sediments of Shandong Peninsula.
Mar. Pollut. Bull.
PUBLISHED: 03-14-2014
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In this study, sources of PAHs in coastal sediments of Shandong Peninsula were apportioned using the chemical mass balance (CMB) model, and source apportionment of carcinogenic and mutagenic potencies was conducted combining CMB with the formula of benzo(a)pyrene carcinogenic equivalent (BaPTEQ) and BaP mutagenic equivalent (BaPMEQ) concentration. Total concentrations of sixteen PAHs in sediment ranged from 181.2 ng g(-1) to 303.6 ng g(-1), and concentrations of eight carcinogenic PAHs (cPAHs) varied from 98.8 ng g(-1) to 141.1 ng g(-1). The BaP played a dominant role for carcinogenic and mutagenic potencies of PAHs, although the IND showed the highest concentration level. The vehicular sources made the highest contribution to BaPTEQ (57.7%) and BaPMEQ (55.5%), while petrogenic source, the highest contributor for PAHs (39.4%), provided the lowest contribution to BaPTEQ (1.1%) and BaPMEQ (1.5%). Besides, the ecotoxicological evaluation, based on Sediment Quality Guidelines (SQGs), showed low ecological risks generally.
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Self-assembled ultrathin nanotubes on diamond (100) surface.
Nat Commun
PUBLISHED: 03-14-2014
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Surfaces of semiconductors are crucially important for electronics, especially when the devices are reduced to the nanoscale. However, surface structures are often elusive, impeding greatly the engineering of devices. Here we develop an efficient method that can automatically explore the surface structures using structure swarm intelligence. Its application to a simple diamond (100) surface reveals an unexpected surface reconstruction featuring self-assembled carbon nanotubes arrays. Such a surface is energetically competitive with the known dimer structure under normal conditions, but it becomes more favourable under a small compressive strain or at high temperatures. The intriguing covalent bonding between neighbouring tubes creates a unique feature of carrier kinetics (that is, one dimensionality of hole states, while two dimensionality of electron states) that could lead to novel design of superior electronics. Our findings highlight that the surface plays vital roles in the fabrication of nanodevices by being a functional part of them.
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A high-grain diet alters the omasal epithelial structure and expression of tight junction proteins in a goat model.
Vet. J.
PUBLISHED: 03-09-2014
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The omasal epithelial barrier plays important roles in maintaining nutrient absorption and immune homeostasis in ruminants. However, little information is currently available about the changes in omasal epithelial barrier function at the structural and molecular levels during feeding of a high-grain (HG) diet. Ten male goats were randomly assigned to two groups, fed either a hay diet (0% grain; n?=?5) or HG diet (65% grain; n?=?5). Changes in omasal epithelial structure and expression of tight junction (TJ) proteins were determined via electron microscopy and Western blot analysis. After 7 weeks on each diet, omasal contents in the HG group showed significantly lower pH (P?<0.001) and significantly higher concentrations of free lipopolysaccharides (LPS; P?=?0.001) than the hay group. The goats fed a HG diet showed profound alterations in omasal epithelial structure and TJ proteins, corresponding to depression of thickness of total epithelia, stratum granulosum, and the sum of the stratum spinosum and stratum basale, marked epithelial cellular damage, erosion of intercellular junctions and down-regulation in expression of the TJ proteins, claudin-4 and occludin. The study demonstrates that feeding a HG diet is associated with omasal epithelial cellular damage and changes in expression of TJ proteins. These research findings provide an insight into the possible significance of diet on the omasal epithelial barrier in ruminants.
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Predictors of successful air enema reduction of intussusception in infants younger than 4 months.
J. Pediatr. Gastroenterol. Nutr.
PUBLISHED: 02-11-2014
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Intussusception is rare in infants younger than 4 months, and the use of air enema for reduction of intussusception has been limited. In this retrospective study, we analyzed the predictors of successful reduction of intussusception using air enema in infants younger than 4 months.
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Comparison of family functioning in families of depressed patients and nonclinical control families in China using the Family Assessment Device and the Family Adaptability and Cohesion Evaluation Scales II.
Ann Clin Psychiatry
PUBLISHED: 02-07-2014
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Family functioning influences the course and long-term outcome for patients with depression. It is important to understand the family functioning of depressed patients from the viewpoint both of patients and their family members. The objective of this study was to explore the association between family functioning and depression in a sample of Chinese families, using the Family Assessment Device (FAD) and the Family Adaptability and Cohesion Evaluation Scales II (FACES II).
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Cellular response of calcium phosphate bone substitute containing hydroxyapatite and tricalcium phosphate.
Implant Dent
PUBLISHED: 01-22-2014
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This study developed calcium phosphate bone substitutes and their microstucture and in vitro cell response were evaluated in comparison with commercial hydroxyapatite (HA).
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Ecdysterone protects gerbil brain from temporal global cerebral ischemia/reperfusion injury via preventing neuron apoptosis and deactivating astrocytes and microglia cells.
Neurosci. Res.
PUBLISHED: 01-12-2014
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Ecdysterone (EDS), a common derivative of ecdysteroid, has shown its effects on alleviating cognitive impairment and improving the cognition and memory. However, the mechanisms remain unknown. Using temporal global forebrain ischemia and reperfusion-induced brain injury as a model system, we investigated the roles of EDS in improving cognitive impairment in gerbil. Our results demonstrated that intraperitoneal injection of EDS obviously increased the number of surviving neuron cells by Nissl and neuronal nuclei (NeuN) staining. Indeed, the protecting effects of EDS are because of its ability to prevent the apoptosis of neuron cells as evidenced by TUNEL staining and caspase-3 deactivation in the brain of temporal global forebrain ischemia/reperfusion-treated gerbil. Moreover, EDS administration suppressed the ischemia stimulated activity of astrocytes and microglia cells by inhibiting the production of tumor necrosis alpha (TNF-?) in the brain of gerbil. More importantly, these actions of neurons and astrocytes/microglia cells in response to EDS treatment played pivotal roles in ameliorating the cognitive impairment in the ischemia/reperfusion-injured gerbil. In view of these observations, we not only decipher the mechanisms of EDS in reducing the syndrome of ischemia, but also provide novel perspectives to combat ischemic stroke.
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Computational insight into p21-activated kinase 4 inhibition: a combined ligand- and structure-based approach.
ChemMedChem
PUBLISHED: 01-06-2014
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p21-Activated kinase 4 (PAK4) is a serine/threonine protein kinase that plays important roles in a wide variety of human diseases including cancer. Targeting this kinase with specific inhibitors is of great interest in the treatment of cancer. In this study, PAK4 and its interaction with ATP-competitive inhibitors was investigated by a combined ligand- and structure-based approach. First, a ligand-based pharmacophore model was generated, consisting of five chemical features: a positive ionizable center, two hydrophobic groups, a hydrogen bond donor, and a hydrogen bond acceptor, which is consistent with available SAR information. The characteristics of the active site were then described as a topological region and used in docking of nine selected inhibitors. Combination of the pharmacophore model and results from the docking studies allowed us to weigh the various pharmacophore features and to identify the positive ionizable center as a spacer rather than an essential point. This research led to the proposal of an interaction model inside the PAK4 active site and provided guidance for the design of more potent PAK4 inhibitors.
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Osteopontin promoter polymorphisms at locus -443 are associated with metastasis and poor prognosis of human intrahepatic cholangiocarcinoma in Chinese population.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Osteopontin (OPN) is known to be a secreted adhesive glycoprotein. Role of OPN in human intrahepatic cholangiocarcinoma (ICC) has not been well understood. This study explored whether genetic variations in the osteopontin gene are associated with ICC risk, progression and metastasis.
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Effects of T-type calcium channel blockers on renal function and aldosterone in patients with hypertension: a systematic review and meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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High blood pressure can cause kidney damage, which can increase blood pressure, leading to a vicious cycle. It is not clear whether the protective effects of T-type calcium channel blockers (T-type CCBs) on renal function are better than those of L-type CCBs or renin-angiotensin system (RAS) antagonists in patients with hypertension.
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Chinese species of genus Notopygus Holmgren (Hymenoptera, Ichneumonidae, Ctenopelmatinae) with description of a new species.
Zookeys
PUBLISHED: 01-01-2014
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A new species, Notopygus longiventris Sun & Sheng, sp. n., collected from Benxi County, Liaoning Province, China, and N. emarginatus Holmgren, 1857, reared from Neurotoma sibirica Gussakovskij (Hymenoptera, Pamphiliidae) from Haicheng, Liaoning Province, are reported. The new species is placed within existing key to species.
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Desoxyrhapontigenin up-regulates Nrf2-mediated heme oxygenase-1 expression in macrophages and inflammatory lung injury.
Redox Biol
PUBLISHED: 01-01-2014
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Heme oxygenase-1 (HO-1) is an important anti-inflammatory, antioxidative and cytoprotective enzyme that is regulated by the activation of the major transcription factor, nuclear factor (erythroid-derived 2)-like 2 (Nrf2). In the present study, six stilbene derivatives isolated from Rheum undulatum L. were assessed for their antioxidative potential. In the tert-butylhydroperoxide (t-BHP)-induced RAW 264.7 macrophage cell line, desoxyrhapontigenin was the most potent component that reduced intracellular reactive oxygen species (ROS) and peroxynitrite. In response to desoxyrhapontigenin, the mRNA expression levels of antioxidant enzymes were up-regulated. An electrophoretic mobility shift assay (EMSA) confirmed that desoxyrhapontigenin promoted the DNA binding of Nrf2 and increased the expression of antioxidant proteins and enzymes regulated by Nrf2. Further investigation utilizing specific inhibitors of Akt, p38, JNK and ERK demonstrated that the phosphatidylinositol 3-kinase (PI3K)/Akt pathway mediates HO-1 expression. Moreover, the increase in Nrf2 expression mediated by treatment with desoxyrhapontigenin was reversed by Nrf2 or Akt gene knock-down. In the LPS-induced in vivo lung inflammation model, pretreatment with desoxyrhapontigenin markedly ameliorated LPS-induced lung inflammation and histological changes. Immunohistochemical analysis of Nrf2, HO-1 and p65 was conducted and confirmed that treatment with desoxyrhapontigenin induced Nrf2 and HO-1 expression but reduced p65 expression. These findings suggest that desoxyrhapontigenin may be a potential therapeutic candidate as an antioxidant or an anti-inflammatory agent.
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[Effects of biochar application on greenhouse gas emission from paddy soil and its physical and chemical properties].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-31-2013
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A field experiment was conducted to investigate the effects of rice straw returning and rice straw biochar and life rubbish biochar application on the greenhouse gas (CH4, CO2 and N2O) emission from paddy soil, its physical and chemical properties, and rice grain yield. Compared with rice straw returning, applying rice straw biochar decreased the cumulative CH4 and N2O emissions from paddy soil significantly by 64.2% - 78.5% and 16.3% - 18.4%, respectively. Whether planting rice or not, the cumulative N2O emission from paddy soil under the applications of rice straw biochar and life rubbish biochar was decreased significantly, compared with that without biochar amendment. Under the condition of no rice planting, applying life rubbish biochar reduced the cumulative CO2 emission significantly by 25.3%. Rice straw biochar was superior to life rubbish biochar in improving soil pH and available potassium content. Both rice straw biochar and life rubbish biochar could increase the soil organic carbon content significantly, but had less effects on the soil bulk density, total nitrogen and available phosphorus contents, cation exchange capacity (CEC), and grain yield. It was suggested that compared with rice straw returning, straw biochar was more effective in improving rice grain yield.
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[Application of multiple lines of evidence analysis technology in the assessment of sites contaminated by heavy metals].
Huan Jing Ke Xue
PUBLISHED: 12-03-2013
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A multiple lines of evidence analysis technology was applied to assess whether sites were contaminated by heavy metals (HMs). Firstly, the baseline upper limit concentration for As and Cr6+ were derived for the two investigated sites based on the analysis of the relative cumulative probability plots of the two metals and their spatial distribution in the soil. The results indicated that the baseline upper limit concentrations for As and Cr6+ at site 1 were 29. 8 mg x kg(-1) and 76. 1 mg x kg(-1), respectively, which were much higher than those reported for the local area by others. But at site 2, the baseline upper limit concentrations for As and Cr6+ were 10.6 mg x kg(-1) and 33 mg x kg(-1), respectively, which were only a little higher than the reported values. Taken the derived baseline concentrations as the assessment criteria, both sites were contaminated by the heavy metals to some degree, which is consistent with the site historical activities review results and element correlation analysis results. At site 1, the As concentration in 3.8% samples exceeded the derived baseline concentration, while the Cr6+ concentration in 6.0% samples exceeded the baseline concentration. At site 2, only the concentration of As in 5.2% samples exceeded the derived baseline value. All the above exceeding rates were much lower than those based on the reported baseline values, which were 77.7% and 96.7% for As and Cr6+ at site 1, respectively and 41.9% for As at site 2. The difference indicates that for a specific site, the baseline concentrations for heavy metals reported in literatures should not be directly applied as the criteria to assess whether the site is contaminated or not, which may cause the results to lose the objectivity and leading to the misallocation of lots of rare resource to remediate soil that maybe not contaminated.
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Biotemplated Synthesis of PZT Nanowires.
Nano Lett.
PUBLISHED: 12-02-2013
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Piezoelectric nanowires are an important class of smart materials for next-generation applications including energy harvesting, robotic actuation, and bioMEMS. Lead zirconate titanate (PZT), in particular, has attracted significant attention, owing to its superior electromechanical conversion performance. Yet, the ability to synthesize crystalline PZT nanowires with well-controlled properties remains a challenge. Applications of common nanosynthesis methods to PZT are hampered by issues such as slow kinetics, lack of suitable catalysts, and harsh reaction conditions. Here we report a versatile biomimetic method, in which biotemplates are used to define PZT nanostructures, allowing for rational control over composition and crystallinity. Specifically, stoichiometric PZT nanowires were synthesized using both polysaccharide (alginate) and bacteriophage templates. The wires possessed measured piezoelectric constants of up to 132 pm/V after poling, among the highest reported for PZT nanomaterials. Further, integrated devices can generate up to 0.820 ?W/cm(2) of power. These results suggest that biotemplated piezoelectric nanowires are attractive candidates for stimuli-responsive nanosensors, adaptive nanoactuators, and nanoscale energy harvesters.
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Facile Synthesis of the Naturally Cytotoxic Triterpenoid Saponin Patrinia-Glycoside B-II and Its Conformer.
Molecules
PUBLISHED: 10-30-2013
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The first chemical synthesis of the natural triterpenoid saponin Patrinia-glycoside B-II, namely oleanolic acid 3-O-?-L-rhamnopyranosyl-(1?2)-[?-D-gluco-pyranosyl-(1?3)]-?-L-arabinopyranoside, has been accomplished in a linear 11-step sequence 11 with 9.4% overall yield. The abnormal 1C4 conformation of the arabinose residue was found to occur via conformational fluctuation during preparation of the intermediates. Molecular mechanism and quantum chemistry calculations showed that Patrinia-glycoside B-II and its conformer 1 cannot interconvert under normal conditions. Preliminary structure-activity relationships studies indicated that the 4C1 chair conformation of the arabinose residue in the unique ?-L-rhamnopyranosyl-(1?2)-?-L-arabinopyranosyl disaccharide moiety is one of the chief positive factors responsible for its cytotoxic activity against tumors.
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[Nationwide speaking tour of standardized diagnosis and treatment for esophageal cancer].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 09-25-2013
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For a long time, the diagnosis and treatment protocol for esophageal cancer has been made either entirely based on the experience of Western countries or on our own experience alone. A suitable standardized guideline for diagnosis and treatment of esophageal cancer in our country has not been estaldished until 2010. Due to lack of opportunities for mutual exchange and learning, the overall level of standardized diagnosis and treatment was relatively low in China. In addition, less advanced technologies were applied and varying treatment protocols were implemented in different districts, the treatment results has been unsatisfactory, and the overall 5-year survival rate after surgical treatment has been maintained from 30% to 40%. Therefore, it is imperative that China needs to conduct its own clinical studies and establish its own suitable standardized treatment and diagnosis guideline for esophageal cancer. This article reviews and also made comments on the process of academic speaking tour and development of standardized diagnosis and treatment guidelines as well as the problems resolved by these activities for esophageal cancer since the beginning of this century.
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Structure-based functional site recognition for p21-activated kinase 4.
Arch. Pharm. Res.
PUBLISHED: 09-07-2013
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Recently, many molecular modeling methods are being developed to better understand the principles underlying protein folding. In the present study, fully flexible dinucleotides d(pApA), d(pApC), d(pApG), d(pApT), d(pCpA), d(pCpC), d(pCpG), d(pCpT), d(pGpA), d(pGpC), d(pGpG), d(pGpT), d(pTpA), d(pTpC), d(pTpG) and d(pTpT) were docked onto the surface of p21-activated kinase 4 (PAK4) kinase domain. The results showed that automated docking was a useful tool to identify the functional sites of PAK4 and it may provide a theoretical basis for the interaction data obtained from previous experiments. Therefore, structure-based docking with fully flexible dinucleotide probes might be a good tool to predict and annotate the functional sites of enzymes.
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Effect of electrical discharging on formation of nanoporous biocompatible layer on Ti-6Al-4V alloys.
Implant Dent
PUBLISHED: 07-13-2013
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In this study, the electrical discharge machining (EDM) was formed on the surface of the Ti-6Al-4V (Ti64) specimen.
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Honokiol thwarts gastric tumor growth and peritoneal dissemination by inhibiting Tpl2 in an orthotopic model.
Carcinogenesis
PUBLISHED: 07-04-2013
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Honokiol is known to suppress the growth of cancer cells; however, to date, its antiperitoneal dissemination effects have not been studied in an orthotopic mouse model. In the present study, we evaluated the antiperitoneal dissemination potential of Honokiol in an orthotopic mouse model and assessed associations with tumor growth factor-?1 (TGF?1) and cells stimulated by a carcinogen, N-methyl-N-nitro-N-nitrosoguanidine (MNNG). Our results demonstrate that tumor growth, peritoneal dissemination and peritoneum or organ metastasis of orthotopically implanted MKN45 cells were significantly decreased in Honokiol-treated mice and that endoplasmic reticulum (ER) stress was induced. Honokiol-treated tumors showed increased epithelial signatures such as E-cadherin, cytokeratin-18 and ER stress marker. In contrast, decreased expression of vimentin, Snail and tumor progression locus 2 (Tpl2) was also noted. TGF?1 and MNNG-induced downregulation of E-cadherin and upregulation of Tpl2 were abrogated by Honokiol treatment. The effect of Tpl2 inhibition in cancer cells or endothelial cells was associated with inactivation of CCAAT/enhancer binding protein B, nuclear factor kappa-light-chain-enhancer of activated B cell and activator protein-1 and suppression of vascular endothelial growth factor. Inhibition of Tpl2 in gastric cancer cells by small interfering RNA or pharmacological inhibitor was found to effectively reduce growth ability and vessel density in vivo. Honokiol-induced reversal of epithelial-to-mesenchymal transition (EMT) and ER stress-induced apoptosis via Tp12 may involve the paralleling processes. Taken together, our results suggest that the therapeutic inhibition of Tpl2 by Honokiol thwarts both gastric tumor growth and peritoneal dissemination by inducing ER stress and inhibiting EMT.
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Mental health care reforms in Asia: the urgency of now: building a recovery-oriented, community mental health service in china.
Psychiatr Serv
PUBLISHED: 07-04-2013
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For the first time in history, China has a mental health legal framework. People in China can now expect a better life and more accessible, better-quality health care services for their loved ones. Development of a community mental health service (CMHS) is at a crossroads. In this new column on mental health reforms in Asia, the authors review the current state of the CMHS in China and propose four strategic directions for future development: building on the strengths of the "686 Project," the 2004 initiative that launched Chinas mental health reform; improving professional skills of the mental health workforce, especially for a recovery approach; empowering families and caregivers to support individuals with severe mental illness; and using information and communications technology to promote self-help and reduce the stigma associated with psychiatric disorders.
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The induction of apoptosis by a newly synthesized diosgenyl saponin through the suppression of estrogen receptor-? in MCF-7 human breast cancer cells.
Arch. Pharm. Res.
PUBLISHED: 07-02-2013
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Estrogen receptor (ER)-? is an important therapeutic target in the clinical treatment of breast cancer. A potential down-regulator of ER-?, diosgenyl ?-L-rhamnopyranosyl-(1?2)-[?-D-xylopyranosyl-(1?4)]-?-L-arabinopyranoside is a newly synthesized diosgenyl saponin named compound 22. This study evaluated the in vitro mechanism of compound 22 as an anticancer agent for breast cancer. Our results indicated that compound 22 selectively inhibited proliferation and induced apoptosis in ER-positive MCF-7 cells, compared with ER-negative MDA-MB-231 and MCF-10A cells. Western blot analysis showed that compound 22 decreased the expression of procaspase-3, procaspase-8, and survivin; and increased the expression of Fas ligand and cleaved PARP1 in MCF-7 cells, indicating that compound 22-induced apoptosis was mediated by the extrinsic pathway. This apoptosis was associated with the suppression of ER-? protein and mRNA expression and the inhibition of ER-DNA binding to the estrogen responsive element. Moreover, ER-? mediated gene expression such as c-Myc and cyclin D1 was reduced, and the activation of p38 and ERK 1/2 was significantly decreased after treatment with compound 22 in MCF-7 cells. Taken together, these results demonstrate that compound 22 down-regulates ER-? expression and induces apoptosis through the extrinsic pathway, suggesting that compound 22 may be effective in the treatment of ER-positive breast cancer.
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Some insights into the binding mechanism of the GABAA receptor: a combined docking and MM-GBSA study.
J Mol Model
PUBLISHED: 06-21-2013
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Gamma-aminobutyric type A receptor (GABAAR) is a member of the Cys-loop family of pentameric ligand gated ion channels (pLGICs). It has been identified as a key target for many clinical drugs. In the present study, we construct the structure of human 2?12?2?2 GABAAR using a homology modeling method. The structures of ten benzodiazepine type drugs and two non-benzodiazepine type drugs were then docked into the potential benzodiazepine binding site on the GABAAR. By analyzing the docking results, the critical residues His102 (?1), Phe77 (?2) and Phe100 (?1) were identified in the binding site. To gain insight into the binding affinity, molecular dynamics (MD) simulations were performed for all the receptor-ligand complexes. We also examined single mutant GABAAR (His102A) in complexes with the three drugs (flurazepam, eszopiclone and zolpidem) to elucidate receptor-ligand interactions. For each receptor-ligand complex (with flurazepam, eszopiclone and zolpidem), we calculated the average distance between the C? of the mutant residue His102A (?1) to the center of mass of the ligands. The results reveal that the distance between the C? of the mutant residue His102A (?1) to the center of flurazepam is larger than that between His102 (?1) to flurazepam in the WT type complex. Molecular mechanic-generalized Born surface area (MM-GBSA)-based binding free energy calculations were performed. The binding free energy was decomposed into ligand-residue pairs to create a ligand-residue interaction spectrum. The predicted binding free energies correlated well (R (2)?=?0.87) with the experimental binding free energies. Overall, the major interaction comes from a few groups around His102 (?1), Phe77 (?2) and Phe100 (?1). These groups of interaction consist of at least of 12 residues in total with a binding energy of more than 1 kcal mol(-1). The simulation study disclosed herein provides a meaningful insight into GABAAR-ligand interactions and helps to arrive at a binding mode hypothesis with implications for drug design.
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Evaluation of ranges of motion of a new constrained acetabular prosthesis for canine total hip replacement.
Biomed Eng Online
PUBLISHED: 06-13-2013
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Total hip replacement (THR) is considered to be the most effective treatment option for advanced osteoarthritis of the hip in large breed dogs. However, a proportion of post-THR patients suffer prosthesis dislocation for various reasons, which may be addressed by a constrained acetabular prosthesis design. The study proposed a new THR with constrained acetabular component that aimed to decrease the incidence of postoperative dislocation while maintaining the necessary range of motion (ROM); and, through computer-simulated implantations, evaluated the ROM of the THR with and without malpositioning of the acetabular component.
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[Application and benefit evaluation of tiered health risk assessment approach on site contaminated by benzene].
Huan Jing Ke Xue
PUBLISHED: 06-11-2013
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The procedures of implementing tiered health risk assessment approach were introduced in detail, and took a large-scale site polluted by benzene in Beijing as an example, the difference on the remediation target of benzene in soil, as well as the corresponding soil remediation volume and costs, were compared. The results indicate that the benzene concentration in soil within 1.5 m in depth and the one below should be remediated to 0.26 mg x kg(-1) and 0.15 mg x kg(-1), respectively, in order to keep the cumulative carcinogenic health risk below 1 x 10(-6) based on tiered II assessment. However, according to tiered III assessment result, which is based on the benzene in soil gas within the contaminated areas in the investigated site, the soil in the corresponding depth should only be remediated to 2.6 mg x kg(-1) and 1.5 mg x kg(-1), respectively. That means the soil remediation volume delimited on tiered III assessment result is less than the one on tiered II by 139 537 m3 and the corresponding remediation costs will be reduced by 57 million Yuan, meaning the enormous economic benefits compared to the costs (around 100 thousands Yuan) spent to carry out tiered III assessment in the site.
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[Application of tiered approach to assess the impact of backfilling remediated soil on groundwater].
Huan Jing Ke Xue
PUBLISHED: 06-11-2013
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The tiered approach for assessing the impact of backfilling treated contaminated soil on groundwater was presented in details with a case study. The soil was contaminated by 1,2-dicholorenthane and 9 other organic pollutants and had been remediated before backfilling to meet the pre-set remediation goals based on health risk assessment. The results from tiered I assessment indicate that the concentrations of 8 contaminants in the leachate of the backfilling soil layer would exceed the assessment standards probably leading to groundwater contamination. However, the results from tiered II assessment, in which the adsorption and retardation of vadose zone soil was taken into account and the concentrations of pollutants reaching the groundwater table were predicated, reveal that only the concentrations of 6 contaminants would exceed the assessment standards. Further, taking the dilution and mixing of the groundwater into consideration, tiered III assessment was adopted and the results reveal that only 4 contaminants were beyond the standards. Finally, tiered IV assessment, aiming at predicting the concentration at the target well downstream, was carried out by considering the retardation of contaminants in saturated layer, and the results indicate only 1 pollutant was above the assessment standard. Therefore, it can be seen that the predicted concentrations of the target pollutants at advanced assessment levels will be closer to those at the target drinking water well and the amount of contaminants whose initially-set remediation goals need to be modified will decrease correspondingly, indicating the reduction in pollution prevention cost, although more efforts should be made and more field data should be collected to implement the advance assessment level.
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A high-grain diet causes massive disruption of ruminal epithelial tight junctions in goats.
Am. J. Physiol. Regul. Integr. Comp. Physiol.
PUBLISHED: 06-05-2013
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Alterations in rumen epithelial tight junctions (TJs) at the tissue and molecular levels during high-grain (HG) diet feeding are unknown. Here, 10 male goats were randomly assigned to either a hay diet (0% grain; n = 5) or HG diet group (65% grain; n = 5) to characterize the changes in ruminal epithelial structure and TJ protein expression and localization using scanning and transmission electron microscopy, quantitative real-time PCR, Western blot analysis, and immunofluorescence. After 7 wk of feeding, ruminal free LPS in HG group increased significantly (P < 0.001) compared with the hay group, and free LPS in the peripheral blood was detectable with concentrations of 0.8 ± 0.20 EU/ml, while not detectable in the control, suggesting a leakage of LPS into the blood in the HG group. Correspondingly, the HG-fed goats showed profound alterations in ruminal epithelial structure and TJ proteins, depicted by marked epithelial cellular damage and intercellular junction erosion, down-regulation of TJ proteins claudin-4, occludin, and zonula occludens-1 mRNA and protein expression, as well as redistribution of claudin-1, claudin-4, and occludin. Furthermore, these changes in TJ proteins in the HG group were coupled with the upregulation of mRNA levels for the cytokines TNF-? and IFN-? in the ruminal epithelia. These results demonstrated for the first time that the HG diet feeding caused disruption of ruminal epithelial TJs that was associated with a local inflammatory response in the rumen epithelium. These findings may provide new insights into understanding the role of TJ proteins in the ruminal epithelial immune homeostasis of ruminants.
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[Case study on health risk assessment based on site-specific conceptual model].
Huan Jing Ke Xue
PUBLISHED: 05-15-2013
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Site investigation was carried out on an area to be redeveloped as a subway station, which is right downstream of the groundwater of a former chemical plant. The results indicate the subsurface soil and groundwater in the area are both polluted heavily by 1,2-dichloroethane, which was caused by the chemical plant upstream with the highest concentration was 104.08 mg.kg-1 for soil sample at 8.6 m below ground and the highest concentration was 18500 microg.L-1 for groundwater. Further, a site-specific contamination conceptual model, giving consideration to the specific structure configuration of the station, was developed, and the corresponding risk calculation equation was derived. The carcinogenic risks calculated with models developed on the generic site conceptual model and derived herein on the site-specific conceptual model were compared. Both models indicate that the carcinogenic risk is significantly higher than the acceptable level which is 1 x 10(-6). The comparison result reveals that the risk calculated with the former models for soil and groundwater are higher than the one calculated with the latter models by 2 times and 1.5 times, respectively. The finding in this paper indicates that the generic risk assessment model may underestimate the risk if specific site conditions and structure configuration are not considered.
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Caesium in high oxidation states and as a p-block element.
Nat Chem
PUBLISHED: 04-28-2013
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The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry, rooted in the atomic shell structure. Within compounds, Group I elements, for example, invariably assume the +1 oxidation state, and their chemical properties differ completely from those of the p-block elements. These general rules govern our understanding of chemical structures and reactions. Here, first-principles calculations show that, under pressure, caesium atoms can share their 5p electrons to become formally oxidized beyond the +1 state. In the presence of fluorine and under pressure, the formation of CsF(n) (n > 1) compounds containing neutral or ionic molecules is predicted. Their geometry and bonding resemble that of isoelectronic XeF(n) molecules, showing a caesium atom that behaves chemically like a p-block element under these conditions. The calculated stability of the CsF(n) compounds shows that the inner-shell electrons can become the main components of chemical bonds.
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A new diagnostic scoring system to differentiate Hirschsprungs disease from Hirschsprungs disease-allied disorders in patients with suspected intestinal dysganglionosis.
Int J Colorectal Dis
PUBLISHED: 03-18-2013
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To create a simple diagnostic scoring system to differentiate Hirschsprungs disease (HD) from Hirschsprungs disease-allied disorders (HAD) in patients with suspected intestinal dysganglionosis (IDs).
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Molecular dynamics investigation of Cl(-) transport through the closed and open states of the 2?12?2?2 GABA(A) receptor.
Biophys. Chem.
PUBLISHED: 03-01-2013
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The ?1?2?2 gamma-aminobutyric type A receptor (GABA(A)R) is one of the most widely expressed GABA(A)R subtypes in the mammalian brain. GABA(A)Rsbelonging to the Cys-loop superfamily of ligand-gated ion channels have been identified as key targets for many clinical drugs, and the motions that govern the gating mechanism are still not well understood. In this study, an open-state GABA(A)R was constructed using the structure of the glutamate-gated chloride channel (GluCl), which has a high sequence identity to GABA(A)R. A closed-state model was constructed using the structure of the nicotinic acetylcholine receptor (nAChR). Molecular dynamics simulations of the open-state and closed-state GABA(A)R were performed. We calculated the electrostatic potential of the two conformations, the pore radius of the two ion channels and the root-mean-square fluctuation. We observed the presence of two positively charged girdles around the ion channel and found flexible regions in the GABA(A)R. Then, the free-energy of chloride ion permeations through the closed-state and open-state G GABA(A)R has been estimated using adaptive biasing force (ABF) simulation. For the closed-state G GABA(A)R, we observed two major energy barriers for chloride ion translocation in the transmembrane domain (TMD). For the open-state GABA(A)R, there was only one energy barrier formed by two Thr261 (?1), two Thr255 (?2) and one Thr271 (?2). By using ABF simulation, the overall free-energy profile is obtained for Cl(-) transporting through GABA(A)R, which gives a complete map of the ion channel of Cl(-) permeation.
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Alignment of graphene sheets in wax composites for electromagnetic interference shielding improvement.
Nanotechnology
PUBLISHED: 03-01-2013
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Rapid advancements in carbon-based fillers have enabled a new and more promising platform in the development of electromagnetic attenuation composites. Alignment of fillers in composites with specific structures and morphologies has been widely pursued to achieve high performance based on taking advantage of unique filler characteristics. In this work, few-layer graphene (FLG), obtained from direct exfoliation of graphite, was fabricated into paraffin wax to prepare FLG/wax composites and investigate their electromagnetic interference (EMI) shielding performance. The as-exfoliated FLG/wax samples have shown much improved EMI performance compared to the commercial graphite/wax ones. For further improvement of EMI shielding performance, split-press-merge approaches were applied to align the FLG fillers to achieve anisotropic characteristics in the plane perpendicular to the pressing direction. Much enhanced EMI shielding performance coupled with an improvement in absorption and reflection was observed in the post-alignment FLG/wax composites. An average interparticle distance model associated with improved electrically conducting interconnection and enlarged effective reflection regions with respect to enhanced reflection efficiency were discussed. The results suggest a platform and promising opportunities for preparing high-performance EMI shielding composites.
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Energetic factors determining the binding of type I inhibitors to c-Met kinase: experimental studies and quantum mechanical calculations.
Acta Pharmacol. Sin.
PUBLISHED: 02-25-2013
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To decipher the molecular interactions between c-Met and its type I inhibitors and to facilitate the design of novel c-Met inhibitors.
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Development of intravenous lipid emulsion of ?-asarone with significantly improved safety and enhanced efficacy.
Int J Pharm
PUBLISHED: 02-24-2013
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Severe adverse events have been frequently associated with taking the commercially available formulation of ?-asarone injection (?-asarone-I). Hence, we sought to develop an intravenous lipid emulsion of ?-asarone (?-asarone-LE), where we hypothesized that these adverse events could be prevented. Using a central composite design-response surface methodology, we developed and optimized an emulsion formulation of ?-asarone-LE that composed of 10.0% (w/v) soybean oil, 0.4% (w/v) ?-asarone, 1.2% (w/v) soybean lecithin, 0.3% (w/v) F68, and 2.2% (w/v) glycerol. The mean particle size of ?-asarone-LE was 226±11 nm, the ?-potential was -25.6±1.2 mV, the encapsulation efficiency was 99.2±0.1% and the drug loading efficiency was 3.45%. Stability, safety, and efficacy studies of ?-asarone-LE were systematically investigated and compared to those of ?-asarone-I. The ?-asarone-LE not only showed a desired stability, but also exhibited excellent safety and improved efficacy in vivo, indicating its great potential for clinical application in the future.
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Inhibition of spontaneous recovery of fear by mGluR5 after prolonged extinction training.
PLoS ONE
PUBLISHED: 02-15-2013
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Fear behavior is vital for survival and involves learning contingent associations of non-threatening cues with aversive stimuli. In contrast, excessive levels of fear can be maladaptive and lead to anxiety disorders. Generally, extensive sessions of extinction training correlates with reduced spontaneous recovery. The molecular mechanisms underlying the long-term inhibition of fear recovery following repeated extinction training are not fully understood. Here we show that in rats, prolonged extinction training causes greater reduction in both fear-potentiated startle and spontaneous recovery. This effect was specifically blocked by metabotropic glutamate receptor 5 (mGluR5), but not by mGluR1 antagonists and by a protein synthesis inhibitor. Similar inhibition of memory recovery following prolonged extinction training was also observed in mice. In agreement with the instrumental role of mGluR5 in the prolonged inhibition of fear recovery, we found that FMR1-/- mice which exhibit enhanced mGluR5-mediated signaling exhibit lower spontaneous recovery of fear after extinction training than wild-type littermates. At the molecular level, we discovered that prolonged extinction training reversed the fear conditioning-induced increase in surface expression of GluR1, AMPA/NMDA ratio, postsynaptic density-95 (PSD-95) and synapse-associated protein-97 (SAP97). Accordingly, delivery of Tat-GluR2(3Y), a synthetic peptide that blocks AMPA receptor endocytosis, inhibited prolonged extinction training-induced inhibition of fear recovery. Together, our results demonstrate that prolonged extinction training results in the mGluR5-dependent long-term inhibition of fear recovery. This effect may involve the degradation of original memory and may explain the beneficial effects of prolonged exposure therapy for the treatment of phobias.
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Abnormal regional homogeneity of resting-state brain activity in patients with HBV-related cirrhosis without overt hepatic encephalopathy.
Liver Int.
PUBLISHED: 02-14-2013
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Many studies have reported that cognitive deficits exist in cirrhotic patients without overt hepatic encephalopathy (OHE). However, the neurobiological mechanisms underlying these deficits are still not fully understood.
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A prognostic biomarker for gastric cancer with lymph node metastases.
Anat Rec (Hoboken)
PUBLISHED: 02-04-2013
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Gastric cancer is one of the leading causes of tumor-related deaths in China. The tumor, node, metastasis (TNM) classification system is useful for predicting clinical prognosis of patients with gastric cancer. However, determining the presence of lymph node involvement in the early stages of gastric cancer is difficult without biopsy. Therefore, it is necessary to identify novel serum biomarkers for TNM cancer staging and prognostic follow-up. In this study, we have reported fibrinopeptide-A (FPA) with alanine truncation at the N-terminal as a novel biomarker to differentiate gastric cancer with and without lymph node metastases. We analyzed 369 individual serum samples including gastric cancer patients without lymph node metastases (n = 33), gastric cancer patients with lymph node metastases (n = 157; confirmed by pathology), and age- and sex-matched healthy individuals (n = 179). The data showed that 85.4% of patients with lymph node metastases were positive for FPA with alanine truncation at the N-terminal (degAla-FPA, 1,465.63 Da), as determined by tandem mass spectrometry (MS). Using degAla-FPA as the biomarker, the sensitivity was 85.4% for gastric cancer patients with lymph node metastases, and the specificity was 100% for gastric cancer patients without lymph node metastases. The high sensitivity and specificity achieved with serum degAla-FPA levels indicated that MS technology could facilitate the discovery of a novel and quantitative prognostic biomarker for gastric cancer with lymph node involvement.
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The effects of calcium channel blockers in the prevention of stroke in adults with hypertension: a meta-analysis of data from 273,543 participants in 31 randomized controlled trials.
PLoS ONE
PUBLISHED: 01-29-2013
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Hypertension is a major risk factor for the development of stroke. It is well known that lowering blood pressure decreases the risk of stroke in people with moderate to severe hypertension. However, the specific effects of calcium channel blockers (CCBs) against stroke in patients with hypertension as compared to no treatment and other antihypertensive drug classes are not known.
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Protective effects of mangiferin in subchronic developmental lead-exposed rats.
Biol Trace Elem Res
PUBLISHED: 01-14-2013
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Lead is a ubiquitous environmental and industrial pollutant. Exposure to excessive amounts of lead is especially harmful to the central nervous systems of infants and young children, and oxidative stress has been reported as a major mechanism of lead-induced toxicity. To evaluate the ameliorative potential of antioxidant mangiferin (MGN) on lead-induced toxicity, Morris water maze test, determination of blood and bone lead concentration, determination of antioxidant status in plasma, as well as observation of ultrastructural changes in the hippocampus were carried out. In the present study, under a transmission electron microscope, ameliorated morphological damages in the hippocampus were observed in MGN-treated groups. Blood and bone lead concentration in MGN-treated groups lowered to some extent (p?
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Development of 2-hydroxymethyl-3,5,6-trimethylpyrazine palmitate-loaded lipid emulsion: formulation, optimization, characterization, pharmacokinetics, biodistribution and pharmacodynamics.
J Drug Target
PUBLISHED: 01-12-2013
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Tetramethylpyrazine (TMP) is used to treat cerebrovascular and cardiovascular diseases. However, it displays a short half-life that restricts clinical applications. 2-Hydroxymethyl-3,5,6-trimethylpyrazine (HTMP) is the principal active metabolite of TMP, with similar activity of TMP. Therefore, it makes sense to improve the biopharmaceutical characteristics via HTMP bypassing TMP.
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Nanoscale flexoelectricity.
Adv. Mater. Weinheim
PUBLISHED: 01-06-2013
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Electromechanical effects are ubiquitous in biological and materials systems. Understanding the fundamentals of these coupling phenomena is critical to devising next-generation electromechanical transducers. Piezoelectricity has been studied in detail, in both the bulk and at mesoscopic scales. Recently, an increasing amount of attention has been paid to flexoelectricity: electrical polarization induced by a strain gradient. While piezoelectricity requires crystalline structures with no inversion symmetry, flexoelectricity does not carry this requirement, since the effect is caused by inhomogeneous strains. Flexoelectricity explains many interesting electromechanical behaviors in hard crystalline materials and underpins core mechanoelectric transduction phenomena in soft biomaterials. Most excitingly, flexoelectricity is a size-dependent effect which becomes more significant in nanoscale systems. With increasing interest in nanoscale and nano-bio hybrid materials, flexoelectricity will continue to gain prominence. This Review summarizes work in this area. First, methods to amplify or manipulate the flexoelectric effect to enhance material properties will be investigated, particularly at nanometer scales. Next, the nature and history of these effects in soft biomaterials will be explored. Finally, some theoretical interpretations for the effect will be presented. Overall, flexoelectricity represents an exciting phenomenon which is expected to become more considerable as materials continue to shrink.
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The cytology, isozyme, HPLC fingerprint, and interspecific hybridization studies of genus epimedium (berberidaceae).
ISRN Pharmacol
PUBLISHED: 01-01-2013
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104 samples from 27 accessions belonging to 12 species of genus Epimedium were studied on the basis of cytology observation, POD (i.e., peroxide) isozyme, high performance liquid chromatography (i.e., HPLC) fingerprint, and interspecific hybridization. The cytology observation showed karyotypes of twelve species studied; all are 2A symmetry type of Stebbins standard and similar to each other, and except for karyotype of E. leptorrhizum which is 2n = 2x = 8m (2SAT) + 4sm, the rest are 2n = 2x = 6m (2SAT) + 6sm. Chromosomes C-banding of barrenwort species varies, with 15 to 22 bands, consisting of centromeric bands, intercalary bands, terminal bands, and middle satellite bands. Results of POD isozyme showed that the zymographs vary greatly and sixteen bands were detected in the eleven species, and each species has its own characteristic bands different from the others. Studies on the HPLC fingerprint showed that the HPLC fingerprint of different species has characteristic peaks, divided into two regions (retention time < 10?min and retention time > 10?min). Results of interspecific hybridization showed that crosses of any combination among seven species studied are successful and the rates of grain set vary greatly. Based on these results, the system and phylogeny of this genus were inferred.
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Wu-ling-san formula prophylaxis against recurrent calcium oxalate nephrolithiasis - a prospective randomized controlled trial.
Afr J Tradit Complement Altern Med
PUBLISHED: 01-01-2013
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Wu-Ling-San (WLS) formula has been proved to prevent calcium oxalate nephrolithiasis both in vitro and in vivo. This is the first prospective, randomized and placebo-controlled clinical trial of WLS in calcium oxalate nephrolithiasis prevention. All patients who enrolled were asked to drink enough fluid to urinate at least 2 L daily during the study period. A 24-hour urine collection was performed to establish the baseline levels of multiple urinary parameters before taking the medicine. The patients were randomized and divided into two groups. The medication group took 2 gm WLS formula three times daily for 1 month. The control group took 2 gm placebo three times daily for 1 month. A 24-hour urine collection was performed to evaluate multiple urinary and serum parameters from all patients during the study period. A total of 39 patients were enrolled and 28 patients completed the study. Fourteen patients were allocated to WLS group and 14 patients to placebo group. After treatment, the mean urine output level increased to 2796.4 ± 525.7 ml/day (percentage of change, 13.9 %) in the WLS formula group. With placebo therapy, the mean decreased slightly to 2521.4 ± 762.7ml/day (percentage of change, -5.7 %). The percentage of change was significantly different between the two groups (independent t-test, P=0.02). No patient complained of side effects, such as fatigue, dizziness, musculoskeletal symptoms, or gastrointestinal disturbance. WLS formula is a promising adjunct to surgical and medical management of kidney stones. Active therapy with WLS formula has a positive effect on diuresis without leading to electrolyte imbalance.
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A new species of Amphibulus Kriechbaumer (Hymenoptera, Ichneumonidae, Cryptinae) from Beijing with a key to species known from the Oriental and Eastern Palaearctic regions.
Zookeys
PUBLISHED: 01-01-2013
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A new species, Amphibulus melanarius Zong, Sun & Sheng, sp.n., belonging to the tribe Phygadeuontini of the subfamily Cryptinae (Hymenoptera: Ichneumonidae), collected from Beijing, China, is reported. A key to the species of the genus Amphibulus Kriechbaumer, 1893 known in the Oriental and Eastern Palaearctic Regions is provided.
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Chinese species of the genus Aptesis Förster (Hymenoptera, Ichneumonidae) parasitizing sawflies, with descriptions of three new species and a key to species.
Zookeys
PUBLISHED: 01-01-2013
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Six species of the genus Aptesis Förster 1850 belonging to the tribe Hemigastrini of the subfamily Cryptinae (Hymenoptera, Ichneumonidae) are reported from China. Three of them, Aptesis elongata Li & Sheng, sp. n., Aptesis melana Li & Sheng, sp. n. and Aptesis nigricoxa Li & Sheng, sp. n. reared from sawflies in China, are new to science. The biology of Aptesis melana is described. A key to the species of Aptesis known from China is provided.
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Hybrid functional electronic structure of PbPdO?, a small-gap semiconductor.
J Phys Condens Matter
PUBLISHED: 11-01-2011
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PbPdO?, a ternary compound containing the lone pair active ion Pb²? and the square planar d?Pd²? ion, has attracted recent interest because of the suggestion that its electronic structure, calculated within density functional theory using either the local density or the generalized gradient approximation, displays zero-gap behavior. In light of the potential ease of doping magnetic ions in this structure, it has been suggested that the introduction of spin, in conjunction with zero band gap, can result in unusual magnetic ground states and unusual magnetotransport. It is known that most electronic structure calculations do not properly obtain a band gap even for the simple oxide PdO, and instead obtain a metal or a zero-gap semiconductor. Here we present density functional calculations employing a screened hybrid functional which correctly obtain a band gap for the electronic structure of PdO. When employed to calculate the electronic ground state of PbPdO?, a band gap is again obtained, which is consistent with both the experimental data on this compound, as well as a consideration of valence states and of metal-oxygen connectivity in the crystal structure. We also present comparisons of the absolute positions (relative to the vacuum level) of the conduction band minima and the valence band maxima in ?-PbO, PdO and PbPdO?, which suggest ease of p-type doping in PbPdO?, that has been observed even in nominally pure materials.
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The design, synthesis and in vitro immunosuppressive evaluation of novel isobenzofuran derivatives.
Bioorg. Med. Chem. Lett.
PUBLISHED: 09-13-2011
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The synthesis and biological evaluation of a series of novel isobenzofuran-based compounds are described. The compounds were evaluated for their immunosuppressive effects of T-cell proliferation and IMPDH type II inhibitor activity in vitro, as well as their structure-activity relationships were assessed. Several compounds demonstrated highly efficacious immunosuppressive properties, especially compounds 2d, 2e, 2h and 2j, which were superior to MPA, while compounds 2k, 2m, 2n, 4c and 5d exhibited an equipotent inhibitory activity compared to MPA. Generally, it was obviously demonstrated that ?,?-unsaturated amides proved more potent than the diamide and urea series. The present study provides a guide for further research on development of safe and effective immunosuppressive agents.
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Is C677T polymorphism in methylenetetrahydrofolate reductase gene a risk factor for diabetic nephropathy or diabetes mellitus in a Chinese population?
Arch. Med. Res.
PUBLISHED: 09-07-2011
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To date, case-control studies on the association between C677T polymorphism in methylenetetrahydrofolate reductase (MTHFR) gene and diabetes mellitus (DM) or diabetic nephropathy (DN) in different populations have provided inconclusive results. To clarify the effect of the C677T polymorphism on the risk of both DM and DN in a Chinese population, a meta-analysis was performed.
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Development of intravenous lipid emulsion of tanshinone IIA and evaluation of its anti-hepatoma activity in vitro.
Int J Pharm
PUBLISHED: 09-07-2011
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The purpose of this study was to develop a lipid emulsion of tanshinone IIA (Tan IIA-LE) for intravenous administration and to investigate its feasibility for future clinical practice. The formulation was optimized using central composite design-response surface methodology (CCD-RSM), and the homogenization process was investigated systematically. The Tan IIA-LE was evaluated in terms of stability, safety and in vitro anti-hepatoma activity. The formulation of Tan IIA-LE is composed of 0.05% (w/v) Tan IIA, 20% (w/v) soybean oil-MCT mixture (1:1, w/w), 1.2% (w/v) soybean lecithin, 0.3% (w/v) F68 and 2.2% (w/v) glycerol, a high pressure homogenization at 100 MPa for 3 cycles was selected as the optimal homogenization process. The Tan IIA-LE was light-sensitive but stable for at least 12 months at room temperature in dark. The safety study demonstrated that the Tan IIA-LE did not cause venous irritation or obvious acute toxicity. Furthermore, the Tan IIA-LE displayed significant anti-tumor activity against human hepatoma cell lines in vitro. Overall, the Tan IIA-LE developed in this study was suggested to be a suitable and safe dosage form of Tan IIA for intravenous administration and has potential in liver cancer therapy in future.
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Association between schizophrenia and single nucleotide polymorphisms in lipoprotein lipase gene in a Han Chinese population.
Psychiatr. Genet.
PUBLISHED: 08-25-2011
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Many studies have suggested that certain types of lipids such as phospholipids, fatty acids, and cholesterols are involved in the pathology of nervous system diseases. Lipoprotein lipase (LPL), as the key enzyme of triglyceride hydrolysis, is expressed in the brain regions functionally relevant to learning, memory, and other cognitive functions. In addition, both genome-wide linkage and association studies in schizophrenia have implicated the chromosome 8p22 region, in which the LPL gene is located. Therefore, LPL is an attractive candidate gene for schizophrenia and we tested this hypothesis in a case-control sample.
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Two new species of genus Ateleute Förster (Hymenoptera, Ichneumonidae, Cryptinae) with a key to the Oriental species.
Zookeys
PUBLISHED: 08-15-2011
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Three species of Ateleute Förster 1869 belonging to the tribe Cryptini of the subfamily Cryptinae (Hymenoptera, Ichneumonidae), collected from Jiangxi Province, China, are reported, of which two are new for science: Ateleute ferruginea Sheng, Broad & Sun, sp. n. and AAteleute zixiensis Sheng, Broad & Sun, sp. n. One, AAteleute densistriata (Uchida, 1955), was previously known from China and Japan. A key to the species of genus Ateleute known in the Oriental Region is provided.
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Analysis of expressed sequence tags from biodiesel plant Jatropha curcas embryos at different developmental stages.
Plant Sci.
PUBLISHED: 08-07-2011
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Jatropha curcas is considered a potential biodiesel feedstock plant whose seeds contain up to 40% oil. However, little is currently known about the seed biology of Jatropha. Therefore, it would be valuable to understand the mechanisms of development and lipid metabolism in Jatropha seeds. In the present study, three cDNA libraries were constructed with mRNA from Jatropha embryos at different stages of seed development. A total of 9844 expressed sequence tags (ESTs) were produced from these libraries, from which 1070 contigs and 3595 singletons were obtained. One hundred and seven unigenes were found to be differentially expressed in the three cDNA libraries of Jatropha embryos, indicating that these genes may play key roles in seed development. We have identified 59 and 61 unigenes that might be involved in the development and lipid metabolism in Jatropha seeds, respectively. Some of these genes may also play important roles in embryogenesis, morphogenesis, defense response and adaptive mechanisms in plants.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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