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Find video protocols related to scientific articles indexed in Pubmed.
Highly efficient separation, enrichment, and recovery of peptides by silica-supported polyethylenimine.
Langmuir
PUBLISHED: 10-07-2014
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Highly efficient and charge-selective adsorption and desorption of peptides at trace level by a solid-phase adsorbent is described. The adsorbent of SiO2@PEI is synthesized by covalent immobilization of branched polyethylenimines (PEI) exclusively on the outer surface of the porous silica particles (?300 ?m). For aqueous peptides (Mw = 600-3000 Da), SiO2@PEI can capture the negatively charged ones and leave the positively charged ones intact, and by adjusting pH of the system peptides with different isoelectric points (pIs) can be well separated. Targeted peptide at low abundance (at least as low as 0.1 mol % with respect to the highest one) can be well separated. The association constants of K > 10(12) M(-1) at pH > pI and K < 10(4) M(-1) at pH < pI are found; that is, selectivity > 10(8) is generally available. Thus, a peptide even at sub-femtomolar level can be extracted and eluted for analysis, and efficient recovery (79-92%) of the peptides is found. The extraction is mainly promoted by multisite electrostatic interaction, and the hydrophilic and cationic properties of PEI at low pH play a unique role in desorption efficiency and selectivity. The unbiased nature of this method renders the adsorbent applicable to the efficient separation of a broad spectrum of peptides, including those with similar pIs.
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Heterobimetallic dinuclear lanthanide alkoxide complexes as acid-base difunctional catalysts for transesterification.
J. Org. Chem.
PUBLISHED: 09-23-2014
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A practical lanthanide(III)-catalyzed transesterification of carboxylic esters, weakly reactive carbonates, and much less-reactive ethyl silicate with primary and secondary alcohols was developed. Heterobimetallic dinuclear lanthanide alkoxide complexes [Ln2Na8{(OCH2CH2NMe2)}12(OH)2] (Ln = Nd (I), Sm (II), and Yb (III)) were used as highly active catalysts for this reaction. The mild reaction conditions enabled the transesterification of various substrates to proceed in good to high yield. Efficient activation of transesterification may be endowed by the above complexes as cooperative acid-base difunctional catalysts, which is proposed to be responsible for the higher reactivity in comparison with simple acid/base catalysts.
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Assessment of Central Retinal Sensitivity Employing Two Types of Microperimetry Devices.
Transl Vis Sci Technol
PUBLISHED: 09-01-2014
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To compare the retinal sensitivity measurements obtained with two microperimeters, the Micro-Perimeter 1 (MP-1) and the Optos optical coherence tomography (OCT)/scanning laser ophthalmoscope (SLO) in subjects with and without maculopathies.
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Plasma metabonomic profiling of lumbar disc herniation and its traditional Chinese medicine subtypes in patients by using gas chromatography coupled with mass spectrometry.
Mol Biosyst
PUBLISHED: 08-22-2014
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Lumbar disc herniation (LDH) is a commonly occurring disease, threatening human health and life quality. Lack of a gold standard of diagnosis has hindered the efficiency and efficacy of clinical therapy against LDH. Traditional Chinese medicine (TCM) has provided an experience-based but subjective diagnosis system for LDH, demanding objective evidence and explanation. In this study, we adopted a metabonomics approach using gas chromatography-mass spectrometry (GC-MS) to profile metabolic characteristics of LDH and its TCM subtypes. Plasma samples of 41 LDH patients and 25 healthy controls were collected. LDH patients were classified into two main subtypes, the reality syndrome and deficiency syndrome, according to TCM theory. By using multivariate statistical analysis and metabolism network analysis, we found diverse perturbations of metabolites in amino acid metabolism and carbohydrate metabolism, in which the amino acids (glutamic acid, aspartic acid, glycine, etc.) were up-regulated and a key carbohydrate metabolite (glucose 1-phosphate) was down-regulated. Few differences were found between the two TCM subtypes. Our findings reveal the metabolic disorders of LDH for the first time and demonstrate the feasibility of the metabonomics approach for LDH research but not for its TCM subtypes.
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Osteoarthritis Pathogenesis: A Review of Molecular Mechanisms.
Calcif. Tissue Int.
PUBLISHED: 07-25-2014
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Osteoarthritis (OA), the most prevalent chronic joint disease, increases in prevalence with age, and affects majority of individuals over the age of 65 and is a leading musculoskeletal cause of impaired mobility in the elderly. Because the precise molecular mechanisms which are involved in the degradation of cartilage matrix and development of OA are poorly understood and there are currently no effective interventions to decelerate the progression of OA or retard the irreversible degradation of cartilage except for total joint replacement surgery. In this paper, the important molecular mechanisms related to OA pathogenesis will be summarized and new insights into potential molecular targets for the prevention and treatment of OA will be provided.
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Anti-DKK1 antibody promotes bone fracture healing through activation of ?-catenin signaling.
Bone
PUBLISHED: 07-11-2014
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In this study we investigated if Wnt/?-catenin signaling in mesenchymal progenitor cells plays a role in bone fracture repair and if DKK1-Ab promotes fracture healing through activation of ?-catenin signaling. Unilateral open transverse tibial fractures were created in CD1 mice and in ?-catenin(Prx1ER) conditional knockout (KO) and Cre-negative control mice (C57BL/6 background). Bone fracture callus tissues were collected and analyzed by radiography, micro-CT (?CT), histology, biomechanical testing and gene expression analysis. The results demonstrated that treatment with DKK1-Ab promoted bone callus formation and increased mechanical strength during the fracture healing process in CD1 mice. DKK1-Ab enhanced fracture repair by activation of endochondral ossification. The normal rate of bone repair was delayed when the ?-catenin gene was conditionally deleted in mesenchymal progenitor cells during the early stages of fracture healing. DKK1-Ab appeared to act through ?-catenin signaling to enhance bone repair since the beneficial effect of DKK1-Ab was abrogated in ?-catenin(Prx1ER) conditional KO mice. Further understanding of the signaling mechanism of DKK1-Ab in bone formation and bone regeneration may facilitate the clinical translation of this anabolic agent into therapeutic intervention.
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Combination Treatment of Biomechanical Support and Targeted Intra-arterial Infusion of Peripheral Blood Stem Cells mobilized by granulocyte-colony stimulating factor for the Osteonecrosis of the Femoral Head: a randomised controlled clinical trial.
J. Bone Miner. Res.
PUBLISHED: 05-20-2014
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To determine the benefits of combination treatment with mechanical support and targeted intra-arterial infusion of peripheral blood stem cells (PBSCs) mobilized by granulocyte-colony stimulating factor (G-CSF) via the medial circumflex femoral artery on the progression of osteonecrosis of the femoral head (ONFH).
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Determination of purine contents in different parts of pork and beef by high performance liquid chromatography.
Food Chem
PUBLISHED: 05-02-2014
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Determination of adenine, hypoxanthine, guanine and xanthine in different parts of pork and beef using high performance liquid chromatography was described. Chromatographic separation was carried out on Waters Atlantis T3 column (4.6mm×250mm×5?m) with column temperature at 30°C. The mobile phase contained 99% 10.0mmol/L ammonium formate solution at pH 3.6 and 1.0% methanol. Chromatography was achieved at a flow rate of 1.0mL/min and detection wavelength at 254nm. The results indicated that total purine amounts in pork rump and beef sirloin were higher than those in other parts (P<0.05). The principal purine bases were hypoxanthine and adenine, and hypoxanthine content was the most highest in all samples (P<0.05). As pork rump and beef sirloin contain considerable amounts of total purine and uricogenic purine base, we suggest that excess consumption of them be avoid, whereas pork loin chop and beef rib eye are more suitable for a low-purine diet.
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Characteristics of Distal Radius Speed of Sound Data in Chinese Mainland Men and Women.
J Clin Densitom
PUBLISHED: 04-16-2014
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Quantitative ultrasound (QUS) assessment of bone health status, as a reliable method, is rapidly gaining popularity. Speed of sound (SOS) is one parameter of skeletal status provided by QUS assessment. The objective of the present study was first to determine the normative distal radius SOS data on healthy Chinese mainland men and women and second to investigate the effects of sex, age, and body size on this parameter. A study cohort consisting of 19,980 healthy Chinese women and 8722 men aged 20-89 yr participated in this investigation. They answered a detailed questionnaire on their healthy condition, and their anthropometric measurements were taken. Their distal radius SOS values were evaluated using the Sunlight ultrasound systems. The distal radius SOS values exhibited a characteristic rise-then-fall pattern with increasing age in both sexes. The peak SOS value occurred at the age of 40-49 both in males and females. Age-related differences were both pronounced among males and females. Pearson correlation and regression analysis showed that age was a major determinant of SOS in both sexes. In females, SOS values had a much stronger correlation with age than male subjects. Body weight was also correlated with SOS but not as well as age. The SOS values of distal radius at present study may be used as normal reference data for Chinese mainland population and will be useful for comparing the results of individual studies and determining diagnostic criteria of osteoporosis by QUS.
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Chemokine receptor 4 gene silencing blocks neuroblastoma metastasis in vitro.
Neural Regen Res
PUBLISHED: 04-05-2014
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This study investigated the effects of small interfering RNA (siRNA)-mediated silencing of chemokine receptor 4 (CXCR4) on the invasion capacity of human neuroblastoma cell line SH-SY5Y in vitro. Three siRNAs targeting CXCR4 were chemically synthesized and individually transfected into SH-SY5Y cells. Expression of CXCR4 mRNA and protein was significantly suppressed in transfected cells by all three sequence-specific siRNAs compared with control groups. Furthermore, the invasion capacity of SH-SY5Y cells was significantly decreased following transfection with CXCR4-specific siRNA compared with the control groups. These data demonstrate that down-regulation of CXCR4 can inhibit in vitro invasion of neuroblastoma.
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Dax1 and Nanog act in parallel to stabilize mouse embryonic stem cells and induced pluripotency.
Nat Commun
PUBLISHED: 02-18-2014
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Nanog expression is heterogeneous and dynamic in embryonic stem cells (ESCs). However, the mechanism for stabilizing pluripotency during the transitions between Nanog(high) and Nanog(low) states is not well understood. Here we report that Dax1 acts in parallel with Nanog to regulate mouse ESC (mESCs) identity. Dax1 stable knockdown mESCs are predisposed towards differentiation but do not lose pluripotency, whereas Dax1 overexpression supports LIF-independent self-renewal. Although partially complementary, Dax1 and Nanog function independently and cannot replace one another. They are both required for full reprogramming to induce pluripotency. Importantly, Dax1 is indispensable for self-renewal of Nanog(low) mESCs. Moreover, we report that Dax1 prevents extra-embryonic endoderm (ExEn) commitment by directly repressing Gata6 transcription. Dax1 may also mediate inhibition of trophectoderm differentiation independent or as a downstream effector of Oct4. These findings establish a basal role of Dax1 in maintaining pluripotency during the state transition of mESCs and somatic cell reprogramming.
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Crystal structure of selenolate-protected Au24(SeR)20 nanocluster.
J. Am. Chem. Soc.
PUBLISHED: 02-18-2014
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We report the X-ray structure of a selenolate-capped Au24(SeR)20 nanocluster (R = C6H5). It exhibits a prolate Au8 kernel, which can be viewed as two tetrahedral Au4 units cross-joined together without sharing any Au atoms. The kernel is protected by two trimeric Au3(SeR)4 staple-like motifs as well as two pentameric Au5(SeR)6 staple motifs. Compared to the reported gold-thiolate nanocluster structures, the features of the Au8 kernel and pentameric Au5(SeR)6 staple motif are unprecedented and provide a structural basis for understanding the gold-selenolate nanoclusters.
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Metal-enhanced fluorescent detection for protein microarrays based on a silver plasmonic substrate.
Analyst
PUBLISHED: 02-08-2014
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This paper presents an ultrasensitive fluorescent detection method through fabricating a silver microarray substrate. Silver nanoparticles (AgNPs) and Ag@Au core-shell nanoparticles with different sizes were first synthesized by a seed-mediated growth method and the metal-enhanced fluorescence of these nanoparticles on different fluorescent dyes was investigated. The results indicated that AgNPs could act as a versatile and effective metal-enhanced fluorescence material for various fluorophores, whereas the enhanced fluorescence from Ag@Au was limited only to certain fluorophores. When the AgNPs were functionalized with aptamers and fluorescent dyes, a good analytical performance for simultaneous detection of human IgE and platelet-derived growth factor-BB (PDGF-BB) could be obtained. AgNPs were not only used as detection tags but also used to fabricate the plasmonic microarray substrate to further enhance the sensitivity of fluorescent detection. As a result, a linear response to PDGF-BB concentration was obtained in the concentration range of 16 pg mL(-1) to 50 ng mL(-1), and the detection limit was 3.2 pg mL(-1). In addition, the AgNP modified plasmonic microarrays showed remarkable recovery and no significant interference from human serum when applied to 2 ng mL(-1) PDGF-BB concentration. The plasmonic microarray substrate demonstrated both high specificity and sensitivity for protein microarray detection and this novel approach has great potential for ultrasensitive detection of protein biomarkers in the bio-medical field.
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Aptamer-functionalized silver nanoparticles for scanometric detection of platelet-derived growth factor-BB.
Anal. Chim. Acta
PUBLISHED: 02-05-2014
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In this work, we reported a scanometric assay system based on the aptamer-functionalized silver nanoparticles (apt-AgNPs) for detection of platelet-derived growth factor-BB (PDGF-BB) protein. The aptamer and ssDNA were bound with silver nanoparticles by self-assembly of sulfhydryl group at 5' end to form the apt-AgNPs probe. The apt-AgNPs probe can catalyze the reduction of metallic ions in color agent to generate metal deposition that can be captured both by human eyes and a flatbed scanner. Two different color agents, silver enhancer solution and color agent 1 (10 mM HAuCl4+2 mM hydroquinone) were used to develop silver and gold shell on the surface of AgNPs separately. The results demonstrated that the formation of Ag core-Au shell structure had some advantages especially in the low concentrations. The apt-AgNPs probe coupled with color agent 1 showed remarkable superiority in both sensitivity and detection limit compared to the apt-AuNPs system. The apt-AgNPs system also produced a wider linear range from 1.56 ng mL(-1) to 100 ng mL(-1) for PDGF-BB with the detection limit lower than 1.56 ng mL(-1). The present strategy was applied to the determination of PDGF-BB in 10% serum, and the results showed that it had good specificity in complex biological media.
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The effects of Liuwei Dihuang on canonical Wnt/?-catenin signaling pathway in osteoporosis.
J Ethnopharmacol
PUBLISHED: 01-30-2014
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The Liuwei Dihuang (LWDH), a wellknown classic traditional Chinese medicine formula, consists of six herbs including Rehmannia glutinosa Libosch. (family: Scrophulariaceae), Cornus officinalis Sieb. (family: Cornaceae), Dioscorea opposite Thunb. (family: Dioscoreaceae), Alisma orientale (G. Samuelsson) Juz (family: Alismataceae), Poria cocos (Schw.) Wolf (family: Polyporaceae) and Paeonia suffruticosa Andrews (family: Paeoniaceae). It has been used clinically in the treatment of many types of diseases with signs of deficiency of Yin in the kidneys for more than 1000 years in China. The purpose of this study was to observe the effects of LWDH on canonical Wnt/?-catenin signaling pathway in osteoporosis.
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Chondrocyte ?-catenin signaling regulates postnatal bone remodeling through modulation of osteoclast formation in a murine model.
PUBLISHED: 01-17-2014
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To investigate whether ?-catenin signaling in chondrocytes regulates osteoclastogenesis, thereby contributing to postnatal bone growth and bone remodeling.
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Design of D-?-A type photoacid generators for high efficiency excitation at 405 nm and 800 nm.
Chem. Commun. (Camb.)
PUBLISHED: 08-14-2013
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New sulfonium salts with diphenylamino asymmetrically substituted stilbene as a D-?-A conjugated system have been synthesized. The resulting photoacid generators exhibit a highly efficient acid photogeneration process by either one-photon 405 nm or two-photon 800 nm excitation.
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High ?-Glucosidase Secretion in Saccharomyces cerevisiae Improves the Efficiency of Cellulase Hydrolysis and Ethanol Production in Simultaneous Saccharification and Fermentation.
J. Microbiol. Biotechnol.
PUBLISHED: 08-10-2013
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Bioethanol production from lignocellulose is considered as a sustainable biofuel supply. However, the low cellulose hydrolysis efficiency limits the cellulosic ethanol production. The cellulase is strongly inhibited by the major end product cellobiose, which can be relieved by the addition of ?-glucosidase. In this study, three ?-glucosidases from different organisms were respectively expressed in Saccharomyces cerevisiae and the ?-glucosidase from Saccharomycopsis fibuligera showed the best activity (5.2 U/ml). The recombinant strain with S. fibuligera ?-glucosidase could metabolize cellobiose with a specific growth rate similar to the control strain in glucose. This recombinant strain showed higher hydrolysis efficiency in the cellulose simultaneous saccharification and fermentation, when using the Trichoderma reesei cellulase, which is short of the ?-glucosidase activity. The final ethanol concentration was 110% (using Avicel) and 89% (using acid-pretreated corncob) higher than the control strain. These results demonstrated the effect of ?-glucosidase secretion in the recombinant S. cerevisiae for enhancing cellulosic ethanol conversion.
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Modulation of a super-Gaussian optical needle with high-NA Fresnel zone plate.
Opt Lett
PUBLISHED: 08-02-2013
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A high NA Fresnel zone plate (FZP) is studied using vectorial angular spectrum theory for realizing the sharpest possible super-Gaussian optical needle with purely longitudinal polarization illuminated by a radially polarized vector beam. Strong dispersion of the FZP results in a light field resembling a super-Gaussian optical needle by selecting an optimal FZP structural wavelength relative to the illumination wavelength and inserting a narrow comb window function into the center-shaded FZP. A 25 ?m long longitudinally polarized flattop optical needle with a transverse beam width of about 0.366? is focused at a distance of 222.5 ?m away from a binary amplitude 3.46 mm diameter FZP for a 532.4 nm wavelength in free space.
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Deletion of the Transforming Growth Factor ? Receptor Type II Gene in Articular Chondrocytes Leads to a Progressive Osteoarthritis-like Phenotype in Mice.
Arthritis Rheum.
PUBLISHED: 08-01-2013
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While transforming growth factor ? (TGF?) signaling plays a critical role in chondrocyte metabolism, the TGF? signaling pathways and target genes involved in cartilage homeostasis and the development of osteoarthritis (OA) remain unclear. Using an in vitro cell culture method and an in vivo mouse genetic approach, we undertook this study to investigate TGF? signaling in chondrocytes and to determine whether Mmp13 and Adamts5 are critical downstream target genes of TGF? signaling.
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Longitudinal spectral domain optical coherence tomography changes in eyes with intraocular lymphoma.
J Ophthalmic Inflamm Infect
PUBLISHED: 07-20-2013
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Cases of patients with primary intraocular lymphoma (PIOL) were retrospectively analyzed to describe the longitudinal intra-retinal morphological changes in PIOL as visualized on images obtained by spectral domain optical coherence tomography (SD-OCT).
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miR-338-3p suppresses neuroblastoma proliferation, invasion and migration through targeting PREX2a.
FEBS Lett.
PUBLISHED: 07-18-2013
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MicroRNAs (miRNA) can regulate cancer cell proliferation and metastasis. Here, we show that miR-338-3p is down-regulated in metastatic tumor tissues compared to primary tumors, and that that miR-338-3p can inhibit cell proliferation by inducing cell cycle arrest, as well as restrain cell migration and invasion. PREX2a is confirmed as a direct target of miR-338-3p. Knockdown of PREX2a inhibits cell proliferation, migration and invasion through the PTEN/Akt pathway. miR-338-3p-dependent inhibition of proliferation and invasion can be rescued by PREXa. Overall, this study demonstrates that miR-338-3p affects the PTEN/Akt pathway by down-regulating PREX2a. This newly identified function of miR-338-3p provides novel insights into neuroblastoma and may foster therapeutic applications.
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Improved insulin secretion following intrapancreatic UCB transplantation in patients with T2DM.
J. Clin. Endocrinol. Metab.
PUBLISHED: 07-16-2013
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Transplantation with stem cells has been reported as a potential treatment for diabetes. However, there are few reports examining transplantation with umbilical cord blood (UCB) in type 2 diabetes (T2DM).
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Vectorial design of super-oscillatory lens.
Opt Express
PUBLISHED: 07-12-2013
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A design and optimization method based on vectorial angular spectrum theory is proposed in this paper for the vectorial design of a super-oscillatory lens (SOL), so that the radially polarized vector beam can be tightly focused. The structure of a SOL is optimized using genetic algorithm and the computational process is accelerated using fast Hankel transform algorithm. The optimized results agree well with what is obtained using the vectorial Rayleigh-Sommerfeld diffraction integral. For an oil immersed SOL, a subwavelength focal spot of about 0.25 illumination wavelength without any significant side lobe can be created at a distance of 184.86 ?m away from a large SOL with a diameter of 1mm. The proposed vectorial design method can be used to efficiently design a SOL of arbitrary size illuminated by various vector beams, with the subwavelength hotspot located in a post-evanescent observation plane.
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Nrf2 suppresses lupus nephritis through inhibition of oxidative injury and the NF-?B-mediated inflammatory response.
Kidney Int.
PUBLISHED: 07-05-2013
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The generation of reactive oxygen species has a pivotal role in both acute and chronic glomerular injuries in patients with lupus nephritis. As the transcription factor Nrf2 is a major regulator of the antioxidant response and is a primary cellular defense mechanism, we sought to determine a role of Nrf2 in the progression of lupus nephritis. Pathological analyses of renal biopsies from patients with different types of lupus nephritis showed oxidative damage in the glomeruli, accompanied by an active Nrf2 antioxidant response. A murine lupus nephritis model using Nrf2(+/+) and Nrf2(-/-) mice was established using pristine injection. In this model, Nrf2(-/-) mice suffered from greater renal damage and had more severe pathological alterations in the kidney. In addition, Nrf2(+/+) mice showed ameliorative renal function when treated with sulforaphane, an Nrf2 inducer. Nrf2(-/-) mice had higher expression of transforming growth factor ?1 (TGF?1), fibronectin, and iNOS. In primary mouse mesangial cells, the nephritogenic monoclonal antibody R4A activated the nuclear factor-kappa B (NF-?B) pathway and increased the level of reactive oxygen species, iNOS, TGF?1, and fibronectin. Knockdown of Nrf2 expression aggravated all aforementioned responses induced by R4A. Thus, these results suggest that Nrf2 improves lupus nephritis by neutralizing reactive oxygen species and by negatively regulating the NF-?B and TGF?1 signaling pathways.Kidney International advance online publication, 11 September 2013; doi:10.1038/ki.2013.343.
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Management of the endoplasmic reticulum stress by activation of the heat shock response in yeast.
FEMS Yeast Res.
PUBLISHED: 06-15-2013
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In yeast Saccharomyces cerevisiae, accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress and activates the unfolded protein response (UPR), which is mediated by Hac1p. The heat shock response (HSR) mediated by Hsf1p, mainly regulates cytosolic processes and protects the cell from stresses. Here, we find that a constitutive activation of the HSR could increase ER stress resistance in both wild-type and UPR-deficient cells. Activation of HSR decreased UPR activation in the WT (as shown by the decreased HAC1 mRNA splicing). We analyzed the genome-wide transcriptional response in order to propose regulatory mechanisms that govern the interplay between UPR and HSR and followed up for the hypotheses by experiments in vivo and in vitro. Interestingly, we found that the regulation of ER stress response via HSR is (1) only partially dependent on over-expression of Kar2p (ER resident chaperone induced by ER stress); (2) does not involve the increase in protein turnover via the proteasome activity; (3) is related to the oxidative stress response. From the transcription data, we also propose that HSR enhances ER stress resistance mainly through facilitation of protein folding and secretion. We also find that HSR coordinates multiple stress-response pathways, including the repression of the overall transcription and translation.
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Chondroprotective activity of a detoxicated traditional Chinese medicine (Fuzi) of Aconitum carmichaeli Debx against severe-stage osteoarthritis model induced by mono-iodoacetate.
J Ethnopharmacol
PUBLISHED: 04-09-2013
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Ethnopharmacological relevance: Fuzi is an effective but toxic traditional Chinese medicine (TCM) derived from Aconitum carmichaeli. In our previous study, detoxicated Fuzi (d-Fuzi) has been originally developed with no toxicity but significant efficacy. However, whether d-Fuzi can be used for therapy of osteoarthritis (OA), remain unknown.Materials and methods: Severe OA model was established by intra-articular mono-iodoacetate (MIA) injection (1.25mg) into rats and orally treated with 2g/ml d-Fuzi at a dosage of 7ml/kg body weight for 28 days. In vivo, the articular radiographic and histopathologic analyses were performed to qualitatively assess the chondroprotective effect of d-Fuzi, followed by quantitative measurements of bone density and Mankin scores. In vitro, such effect on chondrocyte viability after MIA attack was evaluated. Hybrid quadrupole time-of-flight mass spectrometry (QTOF-MS) was performed for chemical analysis of d-Fuzi.Results: d-Fuzi was demonstrated to possess chondroprotective activity on MIA-induced OA model by in vivo preventing the articular degeneration and the reducing of bone density and Mankin score, as well as by in vitro promoting the chondrocyte proliferation and inhibiting the MIA-induced chondrocyte damage. A total of 23 compounds were identified in d-Fuzi, most of which were deduced as the non-toxic derivatives of aconite alkaloids.Conclusions: This is the first report regarding chondroprotective effect and chemical profile of d-Fuzi, originally revealing its great anti-OA potential and thereby providing a promising TCM candidate for OA therapy.
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Association of retinal sensitivity to integrity of photoreceptor inner/outer segment junction in patients with diabetic macular edema.
Ophthalmology
PUBLISHED: 03-15-2013
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To evaluate the relationship between retinal sensitivity and the photoreceptor inner segment/outer segment (IS/OS) layer status in patients with diabetic macular edema (DME).
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Nrf2 modulates contractile and metabolic properties of skeletal muscle in streptozotocin-induced diabetic atrophy.
Exp. Cell Res.
PUBLISHED: 03-02-2013
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The role of Nrf2 in disease prevention and treatment is well documented; however the specific role of Nrf2 in skeletal muscle is not well described. The current study investigated whether Nrf2 plays a protective role in an STZ-induced model of skeletal muscle atrophy. Modulation of Nrf2 through siRNA resulted in a more robust differentiation of C2C12s, whereas increasing Nrf2 with sulforaphane treatment inhibited differentiation. Diabetic muscle atrophy was not dramatically influenced by Nrf2 genotype, since no differences were observed in total atrophy (all fiber types combined) between WT+STZ and KO+STZ animals. Nrf2-KO animals however illustrated alterations in muscle size of Fast, Type II myosin expressing fibers. KO+STZ animals show significant alterations in myosin isoform expression in the GAST. Similarly, KO controls mimic both WT+STZ and KO+STZ muscle alterations in mitochondrial subunit expression. PGC-1?, a well-established player in mitochondrial biogenesis and myosin isoform expression, was decreased in KO control, WT+STZ and KO+STZ SOL muscle. Similarly, PGC-1? protein levels are correlated with Nrf2 levels in C2C12s after modulation by Nrf2 siRNA or sulforaphane treatment. We provide experimental evidence indicating Nrf2 plays a role in myocyte differentiation and governs molecular alterations in contractile and metabolic properties in an STZ-induced model of muscle atrophy.
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Secretory pathway engineering enhances secretion of cellobiohydrolase I from Trichoderma reesei in Saccharomyces cerevisiae.
J. Biosci. Bioeng.
PUBLISHED: 02-15-2013
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Improving the cellulase secretion is beneficial for Saccharomyces cerevisiae used in consolidated bioprocessing (CBP) of cellulosic ethanol. In this study, protein secretory pathway, including protein folding, disulfide bond formation, and protein trafficking and sorting, was modified in S. cerevisiae. The effects of these modifications on the secretion of cellobiohydrolase I (Tr-Cel7A) with its native signal peptide from Trichoderma reesei were investigated. The results showed that overexpression of the protein disulfide isomerase Sc-PDI1 and the plasma membrane targeting soluble N-ethylmaleimide-sensitive factor attachment protein receptor Sc-SSO1, and disruption of the sorting receptor Sc-VPS10 and a Ca(2+)/Mn(2+) ATPase Sc-PMR1, improved respectively the extracellular Tr-Cel7A activities. Among them, disruption of Sc-PMR1 showed better improvement of 162% in the extracellular activity and decreased the glycosylation of Tr-Cel7A. Multiple modifications generally resulted in higher activities. The extracellular activities of the quadruple-modified strain (vps10?/pmr1?/SSO1/PDI1/cel7AF) using p-nitrophenyl-?-d-cellobioside (pNPC) and phosphoric acid swollen cellulose (PASC) as the substrates, respectively, were 3.9-fold and 1.3-fold higher than that of the reference strain cel7AF. The results indicated that engineering of the protein secretory pathway is an effective approach to improve the Tr-Cel7A secretion in S. cerevisiae.
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Development and assessment of a complete-detoxication strategy for Fuzi (lateral root of Aconitum carmichaeli) and its application in rheumatoid arthritis therapy.
J Ethnopharmacol
PUBLISHED: 01-21-2013
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Fuzi (lateral root of Aconitum carmichaeli) is a popular traditional Chinese medicine well known for its both therapeutic and high-toxic activities. Its toxic alkaloid ingredients, mainly aconitine, mesaconitine, and hypaconitine, are responsible for the high toxicity. However, to date, no detoxication strategy is available to completely eliminate Fuzis toxicity, and, whether Fuzis efficacy could be kept after detoxication, remain unknown and debatable.
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(18) FDG PET and PET-CT for the detection of bone metastases in patients with head and neck cancer. A meta-analysis.
J Med Imaging Radiat Oncol
PUBLISHED: 01-20-2013
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We performed a meta-analysis to evaluate (18) FDG PET/PET-CT for the detection of bone metastases in patients with head and neck cancer.
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The efficacy of targeted intraarterial delivery of concentrated autologous bone marrow containing mononuclear cells in the treatment of osteonecrosis of the femoral head: a five year follow-up study.
Bone
PUBLISHED: 01-18-2013
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To investigate the efficacy and safety of targeted delivery of autologous bone marrow mononuclear cells (BMMCs), which are highly enriched with mesenchymal stem cells (BMMSCs), via medial circumflex femoral artery in the treatment of osteonecrosis of the femoral head (ONFH).
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MicroRNA-15a promotes neuroblastoma migration by targeting reversion-inducing cysteine-rich protein with Kazal motifs (RECK) and regulating matrix metalloproteinase-9 expression.
FEBS J.
PUBLISHED: 01-16-2013
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In this study, we found that the expression of miR-15a was positively correlated with neuroblastoma (NB) clinical pathological stage and was negatively correlated with reversion-inducing cysteine-rich protein with Kazal motifs (RECK) expression. Using the enhanced green fluorescent protein (EGFP) reporter construct carrying the 3-UTR of RECK, we identified RECK as a direct target of miR-15a. Suppression of miR-15a significantly decreased the migration ability of GI-LA-N and SK-N-SH cell lines, whereas overexpression of miR-15a increased the migration ability; these effects could be partly reversed by RECK inhibition or ectopic expression. Moreover, inhibition of miR-15a significantly increased secreted matrix metalloproteinase-9 expression in culture medium through regulating the expression of RECK. These findings provide new insights into the characteristics of the miR-15a-RECK-matrix metalloproteinase-9 axis in NB progression, especially in NB migration and invasion.
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MMP13 is a critical target gene during the progression of osteoarthritis.
Arthritis Res. Ther.
PUBLISHED: 01-03-2013
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ABSTRACT: INTRODUCTION: Osteoarthritis (OA) is a degenerative joint disease affecting a large population of people. The mechanism of this highly prevalent disease is not fully understood. Currently there is no effective disease-modifying treatment for OA. The purpose of this study was two-fold: 1) to investigate the role of MMP13 in the development of OA; and 2) to evaluate the efficacy of the MMP13 inhibitor CL82198 as a pharmacologic treatment for preventing OA progression. METHODS: To investigate the role of the endogenous Mmp13 gene in OA development, tamoxifen was administered to two-week-old Col2CreER;Mmp13fx/fx (Mmp13Col2ER) and Cre-negative control mice for five days. OA was induced by meniscal-ligamentous injury (MLI) when the mice were 10 weeks old and MLI or sham-operated joints were harvested 4, 8, 12, or 16 weeks after surgery. To evaluate the efficacy of CL82198, MLI surgery was performed on 10-week-old wild type mice. CL82198 or saline was administered to the mice daily beginning immediately after the surgery for up to 16 weeks. The joint tissues collected from both experiments were evaluated by cartilage grading, histology/histomorphometry, immunohistochemistry (IHC), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The ability of CL82198 to inhibit MMP13 activity in vitro was confirmed by ELISA. RESULTS: The OA progression was decelerated in Mmp13Col2ER mice 8, 12, and 16 weeks post-surgery. Cartilage grading by blinded observers confirmed decreased articular cartilage degeneration in Mmp13Col2ER mice at 8, 12 and 16 weeks compared to Cre-negative mice. Histomorphometric analysis demonstrated that Mmp13Col2ER mice had a higher articular cartilage area and thickness at 12 and 16 weeks post-surgery compared to the control mice. Results of IHC revealed greater type II collagen and proteoglycan expression in Mmp13Col2ER mice. Chondrocyte apoptosis, as determined by TUNEL staining, was higher in control mice compared to Mmp13Col2ER mice. CL82198 inhibited MMP13 activity in conditioned media from vehicle (> 85%) or bone morphogenetic protein 2 (BMP2)-treated (> 90%) primary murine sternal chondrocytes. Intraperitoneal injection of CL82198 decelerated MLI-induced OA progression, increased type II collagen and proteoglycan levels, and inhibited chondrocyte apoptosis compared to saline treatment as determined by OA grading, histology, histomorphometry, IHC, and TUNEL staining, respectively. CONCLUSIONS: Mmp13 is critical for OA progression and pharmacologic inhibition of MMP13 is an effective strategy to decelerate articular cartilage loss in a murine model of injury-induced knee OA.
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Recent progress in understanding molecular mechanisms of cartilage degeneration during osteoarthritis.
Ann. N. Y. Acad. Sci.
PUBLISHED: 12-17-2011
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Osteoarthritis (OA) is a highly prevalent disease affecting more than 20% of American adults. Predispositions include joint injury, heredity, obesity, and aging. Biomechanical alterations are commonly involved. However, the molecular mechanisms of this disease are complex, and there is currently no effective disease-modifying treatment. The initiation and progression of OA subtypes is a complex process that at the molecular level probably involves many cell types, signaling pathways, and changes in extracellular matrix. Ex vivo studies with tissue derived from OA patients and in vivo studies with mutant mice have suggested that pathways involving receptor ligands such as TGF-?1, WNT3a, and Indian hedgehog; signaling molecules such as Smads, ?-catenin, and HIF-2a; and peptidases such as MMP13 and ADAMTS4/5 are probably involved to some degree. This review focuses on molecular mechanisms of OA development related to recent findings.
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Forest soil CO2 fluxes as a function of understory removal and N-fixing species addition.
J Environ Sci (China)
PUBLISHED: 11-10-2011
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We report on the effects of forest management practices of understory removal and N-fixing species (Cassia alata) addition on soil CO2 fluxes in an Eucalyptus urophylla plantation (EUp), Acacia crassicarpa plantation (ACp), 10-species-mixed plantation (Tp), and 30-species-mixed plantation (THp) using the static chamber method in southern China. Four forest management treatments, including (1) understory removal (UR); (2) C. alata addition (CA); (3) understory removal and replacement with C. alata (UR+CA); and (4) control without any disturbances (CK), were applied in the above four forest plantations with three replications for each treatment. The results showed that soil CO2 fluxes rates remained at a high level during the rainy season (from April to September), followed by a rapid decrease after October reaching a minimum in February. Soil CO2 fluxes were significantly higher (P < 0.01) in EUp (132.6 mg/(m2 x hr)) and ACp (139.8 mg/(m2 x hr)) than in Tp (94.0 mg/(m2 x hr)) and THp (102.9 mg/(m2 x hr)). Soil CO2 fluxes in UR and CA were significantly higher (P < 0.01) among the four treatments, with values of 105.7, 120.4, 133.6 and 112.2 mg/(m2 x hr) for UR+CA, UR, CA and CK, respectively. Soil CO2 fluxes were positively correlated with soil temperature (P < 0.01), soil moisture (P < 0.01), NO3(-)-N (P < 0.05), and litterfall (P < 0.01), indicating that all these factors might be important controlling variables for soil CO2 fluxes. This study sheds some light on our understanding of soil CO2 flux dynamics in forest plantations under various management practices.
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Therapeutic potential of Nrf2 activators in streptozotocin-induced diabetic nephropathy.
Diabetes
PUBLISHED: 10-26-2011
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To determine whether dietary compounds targeting NFE2-related factor 2 (Nrf2) activation can be used to attenuate renal damage and preserve renal function during the course of streptozotocin (STZ)-induced diabetic nephropathy.
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BMP2, but not BMP4, is crucial for chondrocyte proliferation and maturation during endochondral bone development.
J. Cell. Sci.
PUBLISHED: 10-07-2011
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The BMP signaling pathway has a crucial role in chondrocyte proliferation and maturation during endochondral bone development. To investigate the specific function of the Bmp2 and Bmp4 genes in growth plate chondrocytes during cartilage development, we generated chondrocyte-specific Bmp2 and Bmp4 conditional knockout (cKO) mice and Bmp2,Bmp4 double knockout (dKO) mice. We found that deletion of Bmp2 and Bmp4 genes or the Bmp2 gene alone results in a severe chondrodysplasia phenotype, whereas deletion of the Bmp4 gene alone produces a minor cartilage phenotype. Both dKO and Bmp2 cKO mice exhibit severe disorganization of chondrocytes within the growth plate region and display profound defects in chondrocyte proliferation, differentiation and apoptosis. To understand the mechanism by which BMP2 regulates these processes, we explored the specific relationship between BMP2 and Runx2, a key regulator of chondrocyte differentiation. We found that BMP2 induces Runx2 expression at both the transcriptional and post-transcriptional levels. BMP2 enhances Runx2 protein levels through inhibition of CDK4 and subsequent prevention of Runx2 ubiquitylation and proteasomal degradation. Our studies provide novel insights into the genetic control and molecular mechanism of BMP signaling during cartilage development.
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Gene expression profile of steroid-induced necrosis of femoral head of rats.
Calcif. Tissue Int.
PUBLISHED: 06-11-2011
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The key to treating steroid-induced necrosis of femoral heads (SINFH) is early diagnosis. Dramatic improvements in diagnosis could be made if the pathogenesis of SINFH was more fully understood; however, the underlying mechanism of this disease is currently unknown. To explore the potential mechanism of SINFH, we performed gene array analysis on a rat model of the disease and compare the expression profile with that of normal rats. A quantitative RT-PCR and immunohistochemistry (IHC) assays were used to confirm the microarray results. Compared to the control group, 190 genes in the experimental group were differentially expressed, with 52 up-regulated and 138 down-regulated. Of these genes, 102 are known (deposited in GenBank), while 88 of them are unknown. The known genes can be divided into several families according to their biological functions, such as oxidative stress, apoptosis, signal transduction, angiogenesis, extracellular matrix, lipid metabolism, and transcription related genes. The results of quantitative RT-PCR and IHC were consistent with gene chip results. Our findings indicate that many genes involved in diverse signaling pathways were differentially expressed between SINFH rats and normal rats. Furthermore, our findings suggest that the development of SINFH is a complicated and dynamic process affected by multiple factors and signaling pathways and regulated by various genes.
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Photochromism-based detection of volatile organic compounds by W-doped TiO2 nanofibers.
J Colloid Interface Sci
PUBLISHED: 04-12-2011
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W-doped TiO(2) nanofibers with various compositions (W/Ti: 2-8%) were fabricated by the electrospinning method from respective precursor solutions containing tungsten(V) pentaethoxide, titanium tetraisopropoxide (TTIP), and polyvinylpyrrolidone (PVP), followed with calcination at 550 °C. Morphological and structural characteristics of these nanofibers were studied with SEM, XRD and XPS. W-doping inhibited the crystal growth and anatase-to-rutile transformation of TiO(2) nanofibers. W-doped TiO(2) nanofiber mats showed good photocatalytic oxidation abilities for acetone. Obvious color change from white to blue of mats during the photocatalysis process can be detected by naked eyes, which provides a good way in detection of pollutants in indoor air, especially for the volatile organic compounds (VOCs).
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TGF-? signaling plays an essential role in the growth and maintenance of intervertebral disc tissue.
FEBS Lett.
PUBLISHED: 02-05-2011
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TGF-? signaling plays a critical role in cartilage and spine tissue development at embryonic stage but its role in postnatal intervertebral disc (IVD) tissue growth and maintenance remain poorly understood. In the present studies, we have deleted the Tgfbr2 gene in inner annulus fibrosus cells of the disc tissue and surrounding growth plate chondrocytes using Col2a1-CreER(T2) transgenic mice. We found that TGF-? signaling is required for normal growth plate cartilage and endplate cartilage growth at postnatal stage. The expression of Mmp13 gene is significantly up-regulated in primary disc cells of Tgfbr2 conditional knockout mice. Deletion of the Mmp13 gene under Tgfbr2 null background completely reverses the abnormal disc phenotype found in Tgfbr2 knockout mice.
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Hydrophobic iron oxide and CdSe/ZnS nanocrystal loaded polyglutamate/polyelectrolyte micro- and nanocapsules.
Nanoscale
PUBLISHED: 08-16-2010
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A novel, simple and generic method for the preparation of hydrophobic nanocrystal loaded composite capsules is introduced. Firstly, magnetic Fe(3)O(4) nanocrystals prepared by pyrolysis of fatty acid iron salts in non-aqueous media were successfully incorporated into water-dispersible polyglutamate/polyelectrolyte capsules by combining an ultrasonic protocol and polyelectrolyte layer-by-layer (LBL) assembly. Then, inspired by the similar synthesis mechanism of oxide and semiconductor nanocrystals based on organometallic approaches in non-aqueous media, two kinds of fluorescent semiconductor quantum dots (zinc sulfide-capped cadmium selenide nanocrystals) were chosen as models to explore QD loaded composite capsules. With rhodamine B isothiocyanate (RBITC) tagging PEI as outer layers, fluorescence micrographs and confocal microscopy images indicate that CdSe/ZnS QDs were successfully incorporated into polyglutamate/polyelectrolyte capsules with almost unchanged optical properties and the color of RBITC tagging PEI shell can be changed under different excitation. Color transformation ascribed to spectral conversion of embedded QDs was also observed after the capsules were stored under day light for days. TEM, electron diffraction (ED), and ESEM revealed that the method leads to well-defined nanocrystal loaded composite nanocapsules and is simple and generic.
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Identification of miRNAs that are associated with tumor metastasis in neuroblastoma.
Cancer Biol. Ther.
PUBLISHED: 03-08-2010
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The discovery of microRNAs (miRNAs) has opened a new avenue for both diagnosis and treatment of cancers. Accumulating experimental evidences indicate that miRNAs are aberrantly expressed in different tumor types and have a critical role in tumorigenesis. However, the miRNA expression profile in neuroblastoma (NB), one of the most common cancer forms in children, has not been well characterized. In the present study, we established a heterotopic transplant mice model of NB and employed miRNA microarray analysis to identify miRNAs that are differentially expressed in metastatic NB compared to primary NB. A list of 54 miRNAs was found to be significantly altered in metastatic tumors compared to primary tumors. These differentially-expressed miRNAs were selectively validated by a stem-loop qRT-PCR assay. Furthermore, we predicted a list of potential miRNA-target pairs that may be involved in the metastasis of neuroblastoma by three different computer-aided algorithms. Taken together, our results indicate that a unique panel of miRNAs are associated with metastatic NB and these differentially-expressed miRNAs may play an important role in the NB metastatic process. This finding may also shed light in our understanding of the nature of metastatic NB and provide a potential novel target for therapeutic treatment of this tumor.
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The atomic and electronic structure of CaF2 and BaF2 crystals with H centers: a hybrid DFT calculation study.
J Phys Condens Matter
PUBLISHED: 01-15-2010
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Using the B3PW method we simulate the ground state of H center systems for CaF(2) and BaF(2) crystals. The energy difference between H centers with different orientations shows that the H center oriented in the [111] direction in alkaline earth fluorides is the most stable. We present the geometric relaxations of the neighboring atoms surrounding the H center. The combination energy of an H center and the formation energy of the related F-H pair in both alkaline earth fluorides are discussed. We also report the electronic structure of the H center systems. The effective charges and spins of the substitutional and interstitial fluorine atoms show that the hole is located at the interstitial fluorine. The band structures are presented. By studying the DOS sketches the constituents of the defect bands are clarified.
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Surgical management of giant liver tumor involving the hepatic hilum of children.
World J Surg
PUBLISHED: 05-09-2009
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Surgical management of giant liver tumors involving the hepatic hilum tends to be very difficult. The present study assessed the feasibility and safety of resection of such liver tumors.
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A facile method for the fabrication of vinyl functionalized hollow silica spheres.
J Colloid Interface Sci
PUBLISHED: 03-28-2009
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In this paper, we adopt a facile method to prepare vinyl functionalized hollow silica spheres. Vinyl functionalized silica shells were coated on positively charged polystyrene particles by hydrolysis and condensation of vinyltriethoxysilane (VTES), the polystyrene cores were dissolved subsequently in the same medium to form monodispersed vinyl functionalized hollow silica spheres. Neither additional dissolving nor a calcination process is necessary to remove the polystyrene cores. Transmission electron microscopy (TEM), FT-IR analysis, TGA and porosity measurements were used to characterize the monodispersed vinyl functionalized hollow silica spheres.
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Mammography visual enhancement in CAD-based breast cancer diagnosis.
Clin Imaging
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This paper presents a novel approach to detect and discriminate abnormal and cueing signatures in mammography through enhancing the imaging contrast. Partial gland and adipose tissues are removed, and thus, the visual effect of mammography will be enhanced. Inspired by single image haze removal, we remove the majority of background tissues by introducing the idea of image matting. Experimental results show the feasibility and performance on distinguishing focuses from healthy tissues in the enhanced mammography. The method has potential applications on breast cancer diagnosis in computer-aided detection.
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Chondrocyte BMP2 signaling plays an essential role in bone fracture healing.
Gene
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The specific role of endogenous Bmp2 gene in chondrocytes and in osteoblasts in fracture healing was investigated by generation and analysis of chondrocyte- and osteoblast-specific Bmp2 conditional knockout (cKO) mice. The unilateral open transverse tibial fractures were created in these Bmp2 cKO mice. Bone fracture callus samples were collected and analyzed by X-ray, micro-CT, histology analyses, biomechanical testing and gene expression assays. The results demonstrated that the lack of Bmp2 expression in chondrocytes leads to a prolonged cartilage callus formation and a delayed osteogenesis initiation and progression into mineralization phase with lower biomechanical properties. In contrast, when the Bmp2 gene was deleted in osteoblasts, the mice showed no significant difference in the fracture healing process compared to control mice. These findings suggest that endogenous BMP2 expression in chondrocytes may play an essential role in cartilage callus maturation at an early stage of fracture healing. Our studies may provide important information for clinical application of BMP2.
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The effects of autologous bone marrow mesenchymal stem cell arterial perfusion on vascular repair and angiogenesis in osteonecrosis of the femoral head in dogs.
Int Orthop
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The purpose of this study was to observe the effects of marrow mesenchymal stem cell (MSCs) arterial perfusion on vascular repair and angiogenesis in osteonecrosis of the femoral head (ONFH).
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A screen-printed, amperometric biosensor for the determination of organophosphorus pesticides in water samples.
J Environ Sci (China)
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An amperometric biosensor based on screen-printed electrodes (SPEs) was developed for the determination of organophosphorus pesticides in water samples. The extent of acetylcholinesterase (AChE) deactivation was determined and quantified for pesticide concentrations in water samples. An enzyme immobilization adsorption procedure and polyacrylamide gel matrix polymerization were used for fabrication of the biosensor, with minimal losses in enzyme activity. The optimal conditions for enzyme catalytic reaction on the SPEs surfaces were acetylthiocholine chloride (ATChCl) concentration of 5 mmol/L, pH 7 and reaction time of 4 min. The detection limits for three organophosphorus pesticides (dichlorvos, monocrotophs and parathion) were in the range of 4 to 7 microg/L when an AChE amount of 0.1 U was used for immobilization.
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Remarkable effect of alkali metal on polymerization of cyclic esters catalyzed by samarium-alkali metal multinuclear alkoxide clusters.
Dalton Trans
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The remarkable effect of alkali metal on catalytic reactivity of samarium-alkali metal multinuclear alkoxide clusters is systematically studied. Three samarium-alkali metal multinuclear alkoxide clusters are synthesized in high yield by the reaction of anhydrous SmCl(3) with different molar ratios of alkali metal alkoxide and MOH (M = Na or K) in tetrahydrofuran (THF). These clusters were fully characterized by elemental analysis, IR, (1)H NMR and single-crystal structural analysis. These clusters exhibited good catalytic activity for the ring-opening polymerization of ?-caprolactone (?-CL), L-lactide (L-LA) and trimethylene carbonate (TMC). It is interesting to note that the catalytic activity is much influenced by the alkali metals of the clusters. For the polymerization of these cyclic esters, the catalytic activities all increase with the increase of the molar ratio of alkali metal to samarium metal.
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Alternative criterion for two-dimensional wrapping percolation.
Phys Rev E Stat Nonlin Soft Matter Phys
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Based on the difference between a spanning cluster and a wrapping cluster, an alternative criterion for testing wrapping percolation is provided for two-dimensional lattices. By following the Newman-Ziff method, the finite size scalings of estimates for percolation thresholds are given. The results are consistent with those from Machtas method.
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Inhibitory control differentiates rare target search performance in children.
Percept Mot Skills
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Age-related differences in rare-target search are primarily explained by the speed-accuracy trade-off, primed responses, or decision making. The goal was to examine how motor inhibition influences visual search. Children pressed a key when a rare target was detected. On no-target trials, children withheld reactions. Response time (RT), hits, misses, correct rejection, and false alarms were measured. Tapping tests assessed motor control. Older children tapped faster, were more sensitive to rare targets (higher d), and reacted more slowly than younger ones. Girls outperformed boys in search sensitivity but not in RT. Motor speed was closely associated with hit rate and RT. Results suggest that development of inhibitory control plays a key role in visual detection. The potential implications for cognitive-motor development and individual differences are discussed.
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New treatment options for noninfectious uveitis.
Dev Ophthalmol
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Autoimmune uveitis is a group of sight-threatening inflammatory diseases associated with an exacerbated immunological response to ocular proteins. The Standardization of Uveitis Nomenclature Working Group Guidelines have recommended the use of corticosteroids as the first line of therapy for patients who present with active uveitis. However, long-term use of corticosteroids is associated with numerous adverse effects including cataract, glaucoma and metabolic disorders. In this context, new drugs developed to treat rheumatic diseases, and other autoimmune diseases, are being employed often as monotherapy or combined with other immunosuppressive drugs in order to decrease the corticosteroid burden on patients and to manage refractive uveitis. These drugs are currently being evaluated in the framework of uveitis and may open a new horizon with less side effects and more responsiveness for chronic cases. Among others, calcineurin inhibitor voclosporin, mammalian target of rapamycin inhibitor sirolimus, and the IL-1 trap rilonacept, are among these new agents and will be scrutinized in detail in this chapter. More efficient modes of drug delivery are also being employed to deliver high concentration of drug locally and to minimize systemic side effects. The new modes of drug delivery that we will describe in the index chapter include nanoparticles and iontophoresis.
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Conditional activation of ?-catenin signaling in mice leads to severe defects in intervertebral disc tissue.
Arthritis Rheum.
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The incidence of low back pain is extremely high and is often linked to intervertebral disc (IVD) degeneration. The mechanism of this disease is currently unknown. This study was undertaken to investigate the role of ?-catenin signaling in IVD tissue function.
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A rhodamine-based "turn-on" fluorescent probe for Fe(3+) in aqueous solution.
Dalton Trans
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A water-soluble "turn-on" fluorescent probe () for Fe(3+) based on rhodamine B was designed and synthesized. The fluorescent probe showed "turn-on" fluorescent and colorimetric responses to Fe(3+) with a high selectivity in water containing less than 1% organic cosolvent. Furthermore, bioimaging investigations indicated that the new probe was cell permeable and suitable for monitoring intracellular Fe(3+) in living cells by confocal microscopy with low cytotoxicity.
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