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Find video protocols related to scientific articles indexed in Pubmed.
Lignans from the bark of Zanthoxylum simulans.
J Asian Nat Prod Res
PUBLISHED: 11-08-2014
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Investigation on the EtOAc extract of the bark of Zanthoxylum simulans led to the isolation of four new lignans including zanthoxylumin A (1), zanthoxylumin B (2), ( - )-magnolin (3), and ( - )-pinoresinol-di-3,3-dimethylallyl ether (4). Their structures were established by comprehensive analysis of the spectral data, especially 1D and 2D NMR spectra.
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Development of covalent inhibitors that can overcome resistance to first-generation FGFR kinase inhibitors.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 10-27-2014
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The human FGF receptors (FGFRs) play critical roles in various human cancers, and several FGFR inhibitors are currently under clinical investigation. Resistance usually results from selection for mutant kinases that are impervious to the action of the drug or from up-regulation of compensatory signaling pathways. Preclinical studies have demonstrated that resistance to FGFR inhibitors can be acquired through mutations in the FGFR gatekeeper residue, as clinically observed for FGFR4 in embryonal rhabdomyosarcoma and neuroendocrine breast carcinomas. Here we report on the use of a structure-based drug design to develop two selective, next-generation covalent FGFR inhibitors, the FGFR irreversible inhibitors 2 (FIIN-2) and 3 (FIIN-3). To our knowledge, FIIN-2 and FIIN-3 are the first inhibitors that can potently inhibit the proliferation of cells dependent upon the gatekeeper mutants of FGFR1 or FGFR2, which confer resistance to first-generation clinical FGFR inhibitors such as NVP-BGJ398 and AZD4547. Because of the conformational flexibility of the reactive acrylamide substituent, FIIN-3 has the unprecedented ability to inhibit both the EGF receptor (EGFR) and FGFR covalently by targeting two distinct cysteine residues. We report the cocrystal structure of FGFR4 with FIIN-2, which unexpectedly exhibits a "DFG-out" covalent binding mode. The structural basis for dual FGFR and EGFR targeting by FIIN3 also is illustrated by crystal structures of FIIN-3 bound with FGFR4 V550L and EGFR L858R. These results have important implications for the design of covalent FGFR inhibitors that can overcome clinical resistance and provide the first example, to our knowledge, of a kinase inhibitor that covalently targets cysteines located in different positions within the ATP-binding pocket.
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Association of Microtubule associated protein tau/Saitohin (MAPT/STH) MAPT_238bp/STH Q7R polymorphisms and Parkinson's disease: A meta-analysis.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-27-2014
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The association between the extended tau haplotype (H1) and susceptibility to Parkinson's disease (PD) was controversial in previous studies. Therefore, we performed this meta-analysis to determine whether the additional polymorphisms in MAPT_238bp and STH Q7R which both included in H1 are associated with PD.
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[On connotation of Jin's three-needle technique].
Zhongguo Zhen Jiu
PUBLISHED: 09-20-2014
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Jin's three-needle technique is named after Professor JIN Rui. The connotation of Jin's three-needle technique is summarized by his followers through long-term teaching and clinical practice. His principle and method of point combination are based on syndrome differentiation of acupuncture. And his unique needling technique and treating principle of mental tranquilization also play an important role in his clinical practice.
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Dysbindin-associated proteome in the p2 synaptosome fraction of mouse brain.
J. Proteome Res.
PUBLISHED: 09-19-2014
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The gene DTNBP1 encodes the protein dysbindin and is among the most promising and highly investigated schizophrenia-risk genes. Accumulating evidence suggests that dysbindin plays an important role in the regulation of neuroplasticity. Dysbindin was reported to be a stable component of BLOC-1 complex in the cytosol. However, little is known about the endogenous dysbindin-containing complex in the brain synaptosome. In this study, we investigated the associated proteome of dysbindin in the P2 synaptosome fraction of mouse brain. Our data suggest that dysbindin has three isoforms associating with different complexes in the P2 fraction of mouse brain. To facilitate immunopurification, BAC transgenic mice expressing a tagged dysbindin were generated, and 47 putative dysbindin-associated proteins, including all components of BLOC-1, were identified by mass spectrometry in the dysbindin-containing complex purified from P2. The interactions of several selected candidates, including WDR11, FAM91A1, snapin, muted, pallidin, and two proteasome subunits, PSMD9 and PSMA4, were verified by coimmunoprecipitation. The specific proteasomal activity is significantly reduced in the P2 fraction of the brains of the dysbindin-null mutant (sandy) mice. Our data suggest that dysbindin is functionally interrelated to the ubiquitin-proteasome system and offer a molecular repertoire for future study of dysbindin functional networks in brain.
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The ubiquitin system in immune regulation.
Adv. Immunol.
PUBLISHED: 09-02-2014
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The ubiquitin system plays a pivotal role in the regulation of immune responses. This system includes a large family of E3 ubiquitin ligases of over 700 proteins and about 100 deubiquitinating enzymes, with the majority of their biological functions remaining unknown. Over the last decade, through a combination of genetic, biochemical, and molecular approaches, tremendous progress has been made in our understanding of how the process of protein ubiquitination and its reversal deubiquitination controls the basic aspect of the immune system including lymphocyte development, differentiation, activation, and tolerance induction and regulates the pathophysiological abnormalities such as autoimmunity, allergy, and malignant formation. In this review, we selected some of the published literature to discuss the roles of protein-ubiquitin conjugation and deubiquitination in T-cell activation and anergy, regulatory T-cell and T-helper cell differentiation, regulation of NF-?B signaling, and hematopoiesis in both normal and dysregulated conditions. A comprehensive understanding of the relationship between the ubiquitin system and immunity will provide insight into the molecular mechanisms of immune regulation and at the same time will advance new therapeutic intervention for human immunological diseases.
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[Analysis of clinical effects of percutaneous vertebroplasty and percutaneous kyphoplasty in treating osteoporotic vertebral compression fracture].
Zhongguo Gu Shang
PUBLISHED: 08-30-2014
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To explore the clinical outcomes of percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) in treating osteoporotic vertebral compression fracture (OVCF).
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Contamination of commercially available seafood by key diarrhetic shellfish poisons along the coast of China.
Environ Sci Pollut Res Int
PUBLISHED: 08-29-2014
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With the increasing number of outbreaks of food-borne diseases caused by okadaic acid (OA) and its analogue dinophysistoxin-1 (DTX-1), two key diarrhetic shellfish poison (DSP) toxins, OA and DTX-1, have become a serious threat to public health and have attracted significant public attention in China. The aim of our study was to monitor OA and DTX-1 contamination in commercially available seafood and to provide references for tracking these toxins and preventing disease outbreaks. From 2010 to 2012, 40 species were collected from six coastal cities of four inland seas in China. An enzyme-linked immunosorbent assay (ELISA) and a lateral flow immunochromatographic (LFIC) test strip were used to analyse the samples, and the results were further confirmed using a commercially available ELISA kit. The monitoring results indicated that 23 of 40 species were positive for contamination. In addition, 14 of the positive species were determined to be inedible because the content of OA and DTX-1 was above the regulatory limit. Simultaneously, we verified that the digestive glands of shellfish tended to accumulate toxin, in contrast to the flesh. The highest concentrations of OA and DTX-1 were recorded in Scapharca broughtonii, which was collected from Qing Dao, in relation to the other analysed species. Moreover, the Arca family as well as Mytilus galloprovincialis were severely contaminated by OA and its analogue. The above results indicate that some of the commercially available seafood from the coastal cities in China may be inedible due to serious marine toxin contamination. The results of this study might play an important role in protecting consumer health and safety screening of marine products.
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Quorum quenching is responsible for the underestimated quorum sensing effects in biological wastewater treatment reactors.
Bioresour. Technol.
PUBLISHED: 08-13-2014
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Quorum sensing (QS) and quorum quenching (QQ) are two antagonistic processes coexisting in various bacterial communities in bioreactors, e.g., activated sludge for biological wastewater treatment. Although QS signal molecules are detected in activated sludge reactors and known to affect sludge properties and reactor performance, there has been no direct evidence to prove the endogenous existence of QQ effects in activated sludge. In this study, for the first time, acyl homoserine lactones-degrading enzymatic activity, a typical QQ effect, was discovered in activated sludge and found to considerably affect the QS detection results. The coexistence of QS and QQ bacteria in activated sludge was further confirmed by bacterial screening and denaturing gradient gel electrophoresis analysis. The method developed in this study could also be used to evaluate QQ activities in bioreactors, and a possible way is provided to tune bioreactor performance through balancing the QS and QQ processes.
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Genome-wide identification of citrus ATP-citrate lyase genes and their transcript analysis in fruits reveals their possible role in citrate utilization.
Mol. Genet. Genomics
PUBLISHED: 08-13-2014
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ATP-citrate lyase (ACL, EC4.1.3.8) catalyzes citrate to oxaloacetate and acetyl-CoA in the cell cytosol, and has important roles in normal plant growth and in the biosynthesis of some secondary metabolites. We identified three ACL genes, CitACL?1, CitACL?2, and CitACL?1, in the citrus genome database. Both CitACL?1 and CitACL?2 encode putative ACL ? subunits with 82.5 % amino acid identity, whereas CitACL?1 encodes a putative ACL ? subunit. Gene structure analysis showed that CitACL?1 and CitACL?2 had 12 exons and 11 introns, and CitACL?1 had 16 exons and 15 introns. CitACL?1 and CitACL?1 were predominantly expressed in flower, and CitACL?2 was predominantly expressed in stem and fibrous roots. As fruits ripen, the transcript levels of CitACL?1, CitACL?1, and/or CitACL?2 in cultivars 'Niuher' and 'Owari' increased, accompanied by significant decreases in citrate content, while their transcript levels decreased significantly in 'Egan No. 1' and 'Iyokan', although citrate content also decreased. In 'HB pummelo', in which acid content increased as fruit ripened, and in acid-free pummelo, transcript levels of CitACL?2, CitACL?1, and/or CitACL?1 increased. Moreover, mild drought stress and ABA treatment significantly increased citrate contents in fruits. Transcript levels of the three genes were significantly reduced by mild drought stress, and the transcript level of only CitACL?1 was significantly reduced by ABA treatment. Taken together, these data indicate that the effects of ACL on citrate use during fruit ripening depends on the cultivar, and the reduction in ACL gene expression may be attributed to citrate increases under mild drought stress or ABA treatment.
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Whole-animal chemical screen identifies colistin as a new immunomodulator that targets conserved pathways.
MBio
PUBLISHED: 08-12-2014
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The purpose of this study was to take advantage of the nematode Caenorhabditis elegans to perform a whole-animal chemical screen to identify potential immune activators that may confer protection against bacterial infections. We identified 45 marketed drugs, out of 1,120 studied compounds, that are capable of activating a conserved p38/PMK-1 mitogen-activated protein kinase pathway required for innate immunity. One of these drugs, the last-resort antibiotic colistin, protected against infections by the Gram-negative pathogens Yersinia pestis and Pseudomonas aeruginosa but not by the Gram-positive pathogens Enterococcus faecalis and Staphylococcus aureus. Protection was independent of the antibacterial activity of colistin, since the drug was administered prophylactically prior to the infections and it was also effective against antibiotic-resistant bacteria. Immune activation by colistin is mediated not only by the p38/PMK-1 pathway but also by the conserved FOXO transcription factor DAF-16 and the transcription factor SKN-1. Furthermore, p38/PMK-1 was found to be required in the intestine for immune activation by colistin. Enhanced p38/PMK-1-mediated immune responses by colistin did not reduce the bacterial burden, indicating that the pathway plays a role in the development of host tolerance to infections by Gram-negative bacteria.
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In vivo RNA interference screens identify regulators of antiviral CD4(+) and CD8(+) T cell differentiation.
Immunity
PUBLISHED: 08-04-2014
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Classical genetic approaches to examine the requirements of genes for T cell differentiation during infection are time consuming. Here we developed a pooled approach to screen 30-100+ genes individually in separate antigen-specific T cells during infection using short hairpin RNAs in a microRNA context (shRNAmir). Independent screens using T cell receptor (TCR)-transgenic CD4(+) and CD8(+) T cells responding to lymphocytic choriomeningitis virus (LCMV) identified multiple genes that regulated development of follicular helper (Tfh) and T helper 1 (Th1) cells, and short-lived effector and memory precursor cytotoxic T lymphocytes (CTLs). Both screens revealed roles for the positive transcription elongation factor (P-TEFb) component Cyclin T1 (Ccnt1). Inhibiting expression of Cyclin T1, or its catalytic partner Cdk9, impaired development of Th1 cells and protective short-lived effector CTL and enhanced Tfh cell and memory precursor CTL formation in vivo. This pooled shRNA screening approach should have utility in numerous immunological studies.
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Effect of the -2081G/A polymorphism of the TLR4 gene and its interaction with Helicobacter pylori infection on the risk of gastric cancer in Chinese individuals.
Genet Test Mol Biomarkers
PUBLISHED: 08-01-2014
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Toll-like receptor 4 (TLR4) plays an important role in gastric carcinoma. Using a case-control study, we analyzed the genotypic distribution of TLR4 rs10983755 (-2081G/A) and rs11536878 in a Chinese population and investigated the effect of their interactions with Helicobacter pylori infection on susceptibility to gastric cancer (GC) and atrophic gastritis (AG).
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[Inhibitory activities of 3-trifluoromethyl benzamide derivatives against the entry of H5N1 influenza viruses].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 07-25-2014
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To study the inhibitory activities of 3-trifluoromethyl benzamide derivatives against the entry of H5N1 influenza viruses.
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Clostridium difficile carriage in hospitalized cancer patients: a prospective investigation in eastern China.
BMC Infect. Dis.
PUBLISHED: 07-16-2014
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Clostridium difficile carriage has been considered as a potential source for the deadly infection, but its role in cancer patients is still unclear. We aimed to identify the clinical and immunological factors that are related to C. difficile carriage in Chinese cancer patients.
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Analysis of aroma-active compounds in three sweet osmanthus (Osmanthus fragrans) cultivars by GC-olfactometry and GC-MS.
J Zhejiang Univ Sci B
PUBLISHED: 07-09-2014
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Aroma is the core factor in aromatherapy. Sensory evaluation of aromas differed among three sweet osmanthus (Osmanthus fragrans) cultivar groups. The purpose of this study was to investigate the aroma-active compounds responsible for these differences.
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Site-specific qualitative and quantitative analysis of the N- and O-glycoforms in recombinant human erythropoietin.
Anal Bioanal Chem
PUBLISHED: 05-26-2014
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Recombinant human erythropoietin (rhEPO) has been extensively used as a pharmaceutical product for treating anemia. Glycosylation of rhEPO affects the biological activity, immunogenicity, pharmacokinetics, and in-vivo clearance rate of rhEPO. Characterization of the glycosylation status of rhEPO is of great importance for quality control. In this study, we established a fast and comprehensive approach for reliable characterization and relative quantitation of rhEPO glycosylation, which combines multiple-enzyme digestion, hydrophilic-interaction chromatography (HILIC) enrichment of glycopeptides, and tandem mass spectrometry (MS) analysis. The N-linked and O-linked intact glycopeptides were analyzed with high-resolution and high-accuracy (HR-AM) mass spectrometry using an Orbitrap. In total, 74 intact glycopeptides from four glycosylation sites at N24, N38, N83, and O126 were identified, with the simultaneous determination of peptide sequences and glycoform compositions. The extracted ion chromatograms based on the HR-AM data enabled relative quantification of glycoforms. Our results could be extended to quality control of rhEPO or could help establish detection approaches for glycosylation of other proteins.
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A pharmacodynamic simulation to evaluate tigecycline in treatment of nosocomial pneumonia caused by multidrug-resistant Acinetobacter baumannii.
Pak J Pharm Sci
PUBLISHED: 05-10-2014
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The shortage of effective antibiotics against multidrug-resistant Acinetobacter baumannii (MDR-Ab) has posed great threat to the public health. But the advent of tigecycline gives us new hope. The goal of our research was to assess the clinical efficacy of tigecycline at different doses by using a pharmacokinetic/pharmacodynamic (PK/PD) model which can incorporate pharmacokinetic data of tigecycline from patients with pneumonia and MICs of MDR-Ab from a tertiary hospital. A 10000-patient Monte-Carlo Simulation based on the PK/PD model was conducted to calculate the probability of target attainment (PTA) and the cumulative fraction of response (CFR) of tigecycline. 97% isolates displayed susceptibility and 3% were tigecycline-intermediate strains and the values of MIC ranged from 0.125 to 4 ? g/ml. A CFR of 61.62% was predicted for tigecycline at current dosage (50 mg q12h). When the dosage was increased, the predicted CFRs for 75 mg q12h, 100 mg q12h, 125 mg q12h, 150 mg q12h were 81.00%, 89.86%, and 94.57%, 96.77%, respectively. Despite presented higher susceptibility, the CFR obtained was not optimal at current dosage. A higher CFR indicating a better clinical efficacy can be gained by the increased dosage.
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Cytochrome P450 1A1 (CYP1A1) polymorphism and susceptibility to esophageal cancer: an updated meta-analysis of 27 studies.
Tumour Biol.
PUBLISHED: 04-29-2014
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Cytochrome P450 1A1 (CYP1A1) polymorphisms are known to play a crucial role in the development and metastasis of malignant diseases including esophageal cancer. However, the results of previous studies investigating the association between CYP1A1 polymorphisms and esophageal cancer risk have been inconsistent. This meta-analysis of 27 eligible studies, encompassing 4,215 esophageal cancer cases and 6,339 control subjects, pooled the odds ratios (ORs) with corresponding 95 % confidence intervals (95 % CI) to assess this association. The effects of ethnicity (Caucasian and Asian) and histopathology type (esophageal squamous cell carcinoma and esophageal adenocarcinoma) were considered in subgroup analyses. A significant association was observed between the CYP1A1 Ile/Val gene polymorphism and esophageal cancer in all of the genetic models (Ile/Val vs. Ile/Ile, OR?=?1.41, 95 % CI?=?1.25-1.58; Val/Val vs. Ile/Ile, OR?=?1.94, 95 % CI?=?1.34-2.82; Ile/Val?+?Val/Val vs. Ile/Ile, OR?=?1.49, 95 % CI?=?1.33-1.66). The subgroup analysis based on ethnicity showed that the association between the CYP1A1 Ile/Val polymorphism and esophageal cancer existed in Asian and Caucasian populations. However, no association was observed between the CYP1A1 MspI polymorphism and esophageal cancer in either subgroup or in the overall population. These results suggested that the CYP1A1 Ile/Val polymorphism was associated with an increased risk of esophageal cancer, whereas the CYP1A1 MspI polymorphism may not have increased susceptibility to esophageal cancer. Further studies are required to confirm these findings.
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Methylenetetrahydrofolate reductase (MTHFR) polymorphism susceptibility to schizophrenia and bipolar disorder: an updated meta-analysis.
J Neural Transm
PUBLISHED: 04-21-2014
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Previous studies examining the possible role of the methylenetetrahydrofolate reductase (MTHFR) polymorphisms in the development of schizophrenia (SZ) and bipolar disorder (BPD) have provided inconclusive findings, this meta-analysis was therefore designed to get a more reliable assessment. A total of 38 articles were identified through a search of electronic databases, up to 27 February 2014. Odds ratios (ORs) with 95 % confidence interval (CIs) were calculated using random effects models. Meta-analysis showed that MTHFR C677T was significantly associated with SZ, the highest OR was found for the recessive model (for TT vs. CT + CC: OR = 1.34, 95 % CI: 1.18-1.53); a marginal association of MTHFR C677T with increased risk of BPD has also been found for the recessive model (OR = 1.26, 95 % CI: 1.00-1.59). Subgroup analysis by ethnicity indicated that the significant association with SZ and BPD existed among Asian and African populations, but not for the white. MTHFR A1298C was significant associated with SZ, the highest OR for the dominant model (OR = 1.13, 95 % CI: 1.03-1.24). Subgroup analysis indicated a significant association with SZ existed in Asian populations, not among the white populations and no significant association was detected between the MTHFR A1298C and BPD in all groups. We conclude that MTHFR polymorphism is associated with SZ and BPD among Asian, African populations, but not the white.
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Identification and transcript analysis of two glutamate decarboxylase genes, CsGAD1 and CsGAD2, reveal the strong relationship between CsGAD1 and citrate utilization in citrus fruit.
Mol. Biol. Rep.
PUBLISHED: 03-26-2014
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Glutamate decarboxylase (GAD, EC 4.1.1.15) has been suggested to be a key, regulatory point in the biosynthesis of ?-aminobutyrate (GABA) and in the utilization of citric acid through GABA shunt pathway. In this study we discovered two GAD genes, named as CsGAD1 and CsGAD2, in citrus genome database and then successfully cloned. Both CsGAD1 and CsGAD2 have a putative pyridoxal 5-phosphate binding domain in the middle region and a putative calmodulin-binding domain at the carboxyl terminus. Gene structure analysis showed that much difference exists in the size of exons and introns or in cis-regulatory elements in promoter region between the two GAD genes. Gene expression indicated that CsGAD1 transcript was predominantly expressed in flower and CsGAD2 transcript was predominantly expressed in fruit juice sacs; in the ripening fruit, CsGAD1 transcript level was at least 2-time higher than CsGAD2 transcript level. Moreover, CsGAD1 transcript level was increased significantly along with the increase of GAD activity and accompanied by a significant decrease of titratable acid (TA), suggesting that it is CsGAD1 rather than CsGAD2 plays a role in the citric acid utilization during fruit ripening. In addition, injection of abscisic acid and foliar spray of K2SO4 significantly increased the TA content of Satsuma mandarin, and significantly decreased GAD activity as well as CsGAD1 transcript, further suggesting the important role of CsGAD1 in the citrate utilization of citrus fruit.
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High-throughput absolute quantification of proteins using an improved two-dimensional reversed-phase separation and quantification concatemer (QconCAT) approach.
Anal Bioanal Chem
PUBLISHED: 03-21-2014
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Stable isotope dilution-selective reaction monitoring-mass spectrometry (SID-SRM-MS) has been widely used for the absolute quantitative analysis of proteins. However, when performing the large-scale absolute quantification of proteins from a more complex tissue sample, such as mouse liver, in addition to a high-throughput approach for the preparation and calibration of large amounts of stable-isotope-labelled internal standards, a more powerful separation method prior to SRM analysis is also urgently needed. To address these challenges, a high-throughput absolute quantification strategy based on an improved two-dimensional reversed-phase (2D RP) separation and quantification concatemer (QconCAT) approach is presented in this study. This strategy can be used to perform the simultaneous quantification of hundreds of proteins from mouse liver within one week of total MS measurement time. By using calibrated synthesised peptides from the protein glutathione S-transferase (GST), large amounts of GST-tagged QconCAT internal standards corresponding to hundreds of proteins can be accurately and rapidly quantified. Additionally, using an improved 2D RP separation method, a mixture containing a digested sample and QconCAT standards can be efficiently separated and absolutely quantified. When a maximum gradient of 72 min is employed in the first LC dimension, resulting in 72 fractions, identification and absolute quantification experiments for all fractions can be completed within one week of total MS measurement time. The quantification approach developed here can further extend the dynamic range and increase the analytical sensitivity of SRM analysis of complex tissue samples, thereby helping to increase the coverage of absolute quantification in a whole proteome.
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'Druggable' alterations detected by Ion Torrent in metastatic colorectal cancer patients.
Oncol Lett
PUBLISHED: 03-20-2014
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The frequency and poor prognosis of patients with metastatic colorectal cancer (mCRC) emphasizes the requirement for improved biomarkers for use in the treatment and prognosis of mCRC. In the present study, somatic variants in exonic regions of key cancer genes were identified in mCRC patients. Formalin-fixed, paraffin-embedded tissues obtained by biopsy of the metastases of mCRC patients were collected, and the DNA was extracted and sequenced using the Ion Torrent Personal Genome Machine. For the targeted amplification of known cancer genes, the Ion AmpliSeq™ Cancer Panel, which is designed to detect 739 Catalogue of Somatic Mutations in Cancer (COSMIC) mutations in 604 loci from 46 oncogenes and tumor suppressor genes using as little as 10 ng of input DNA, was used. The sequencing results were then analyzed using the Ampliseq™ Variant Caller plug-in within the Ion Torrent Suite software. In addition, Ingenuity Pathway software was used to perform a pathway analysis. The Cox regression analysis was also conducted to investigate the potential correlation between alteration numbers and clinical factors, including response rate, disease-free survival and overall survival. Among 10 specimens, 65 genetic alterations were identified in 24 genes following the exclusion of germline mutations using the SNP database, whereby 41% of the alterations were also present in the COSMIC database. No clinical factors were found to significantly correlate with the alteration numbers in the patients by statistical analysis. However, pathway analysis identified 'colorectal cancer metastasis signaling' as the most commonly mutated canonical pathway. This analysis further revealed mutated genes in the Wnt, phosphoinositide 3-kinase (PI3K)/AKT and transforming growth factor (TGF)-?/SMAD signaling pathways. Notably, 11 genes, including the expected APC, BRAF, KRAS, PIK3CA and TP53 genes, were mutated in at least two samples. Notably, 90% (9/10) of mCRC patients harbored at least one 'druggable' alteration (range, 1-6 alterations) that has been linked to a clinical treatment option or is currently being investigated in clinical trials of novel targeted therapies. These results indicated that DNA sequencing of key oncogenes and tumor suppressors enables the identification of 'druggable' alterations for individual colorectal cancer patients.
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Islet neogenesis-associated protein-related pentadecapeptide improves the function of allograft after islets transplantation.
J. Pediatr. Endocrinol. Metab.
PUBLISHED: 03-19-2014
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Abstract Objective: To investigate the protective effects of a pentadecapeptide of islet neogenesis-associated protein (INGAP-PP) on transplanted islets function.
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Ertapenem versus ceftriaxone for the treatment of complicated infections: a meta-analysis of randomized controlled trials.
Chin. Med. J.
PUBLISHED: 03-14-2014
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Ertapenem has been demonstrated to be highly effective for the treatment of complicated infections. The aim of this study was to compare the efficacy and safety of ertapenem with ceftriaxone.
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The E3 ubiquitin ligase Itch is required for the differentiation of follicular helper T cells.
Nat. Immunol.
PUBLISHED: 03-10-2014
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Follicular helper T cells (T(FH) cells) are responsible for effective B cell-mediated immunity, and Bcl-6 is a central factor for the differentiation of T(FH) cells. However, the molecular mechanisms that regulate the induction of T(FH) cells remain unclear. Here we found that the E3 ubiquitin ligase Itch was essential for the differentiation of T(FH) cells, germinal center responses and immunoglobulin G (IgG) responses to acute viral infection. Itch acted intrinsically in CD4(+) T cells at early stages of T(FH) cell development. Itch seemed to act upstream of Bcl-6 expression, as Bcl-6 expression was substantially impaired in Itch(-/-) cells, and the differentiation of Itch(-/-) T cells into T(FH) cells was restored by enforced expression of Bcl-6. Itch associated with the transcription factor Foxo1 and promoted its ubiquitination and degradation. The defective T(FH) differentiation of Itch(-/-) T cells was rectified by deletion of Foxo1. Thus, our results indicate that Itch acts as an essential positive regulator in the differentiation of T(FH) cells.
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Ubiquitin ligase Cbl-b acts as a negative regulator in discoidin domain receptor 2 signaling via modulation of its stability.
FEBS Lett.
PUBLISHED: 02-19-2014
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Discoidin domain receptor 2 (DDR2), a collagen receptor tyrosine kinase, initiates signal transduction upon collagen binding, but little is known as to how DDR2 signaling is negatively regulated. Herein we demonstrate that Cbl family member Cbl-b predominantly promotes the ubiquitination of DDR2 upon collagen II stimulation. Cbl-b-mediated ubiquitination accelerates the degradation of activated DDR2. Finally, the production of MMP-13, a downstream target of DDR2, is enhanced in Cbl-b-knocked down MC3T3-E1 cells and Cbl-b-deficient mouse primary synovial fibroblasts. Thus, Cbl-b, by promoting the ubiquitination and degradation of DDR2, functions as a negative regulator in the DDR2 signaling pathway.
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Dual matrix-based immobilized trypsin for complementary proteolytic digestion and fast proteomics analysis with higher protein sequence coverage.
Anal. Chem.
PUBLISHED: 01-21-2014
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In an age of whole-genome analysis, the mass spectrometry-based bottom-up strategy is now considered to be the most powerful method for in-depth proteomics analysis. As part of this strategy, highly efficient and complete proteolytic digestion of proteins into peptides is crucial for successful proteome profiling with deep coverage. To achieve this goal, prolonged digestion time and the use of multiple proteases have been adopted. The long digestion time required and tedious sample treatment steps severely limit the sample processing throughput. Though utilization of immobilized protease greatly reduces the digestion time, highly efficient proteolysis of extremely complex proteomic samples remains a challenging task. Here, we propose a dual matrix-based complementary digestion method using two types of immobilized trypsin with opposite matrix hydrophobicity prepared by attaching trypsin on hydrophobic or hydrophilic polymer-brush-modified nanoparticles. The polymer brushes on the nanoparticles serve as three-dimensional supports for a large amount of trypsin immobilization and lead to ultrafast and highly efficient protein digestion. More importantly, the two types of immobilized trypsin show high complementarity in protein digestion with only ?60% overlap in peptide identification for yeast and membrane protein of mouse liver. Complementary digestion by applying these two types of immobilized trypsin together leads to obviously enhanced protein and peptide identification. Furthermore, the dual matrix-based complementary digestion shows particular advantage in the digestion of membrane proteins, as twice the number of identified peptides is obtained compared with solution digestion using free proteases, demonstrating its potential as a promising alternative to promote proteomics analysis with higher protein sequence coverage.
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Laser-assisted hatching improves clinical outcomes of vitrified-warmed blastocysts developed from low-grade cleavage-stage embryos: a prospective randomized study.
Reprod. Biomed. Online
PUBLISHED: 01-15-2014
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The aim of this study was to evaluate the effects of quarter zona-pellucida (ZP) opening by laser-assisted hatching (QLAH) on the clinical outcomes following transfer of vitrified-warmed blastocysts developed from low-grade cleavage-stage embryos in patients with all high-grade and fair-grade cleavage-stage embryos transferred without achieving pregnancy. Patients were randomized into two groups: QLAH (n=101) and control (n=102). The implantation and clinical pregnancy rates were significantly higher in the QLAH group compared with the control group (P=0.021 and P=0.034, respectively). The live birth rate of the QLAH group was also higher, although not significantly. When the clinical outcomes according to the day of blastocyst vitrification were compared between the groups, the implantation, clinical pregnancy and live birth rates of the QLAH group were significantly higher (P<0.05) than those of the control group for day 6 blastocysts, but not for day 5 or day 5/day 6 blastocysts. These results suggest that QLAH improves the clinical outcomes of vitrified-warmed blastocysts, especially of day 6 vitrified blastocysts, developed from low-grade cleavage-stage embryos.
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Chlorogenic acid increased acrylamide formation through promotion of HMF formation and 3-aminopropionamide deamination.
J. Hazard. Mater.
PUBLISHED: 01-07-2014
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This research was aimed to investigate why chlorogenic acid, presents at high concentrations in some food raw material, influences acrylamide formation. In the asparagine/glucose Maillard reaction system (pH=6.8), addition of chlorogenic acid significantly increased acrylamide formation and inhibited its elimination. In contrast, the quinone derivative of chlorogenic acid decreased acrylamide formation. Three mechanisms may be involved for increasing acrylamide formation by chlorogenic acid. Firstly, it increased the formation of HMF, which acts as a more efficient precursor than glucose to form acrylamide. Secondly, it decreased activation energy for conversion of 3-aminopropionamide (3-APA) to acrylamide (from 173.2 to 136.6kJ/mol), and enhances deamination from 3-APA. And thirdly, it prevented attack of the produced acrylamide from free radicals by keeping high redox potential during the Maillard reaction.
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Effect of swimming on the production of aldosterone in rats.
PLoS ONE
PUBLISHED: 01-01-2014
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It has been demonstrated that exercise is one of the stresses known to increase the aldosterone secretion. Both potassium and angiotensin II (Ang II) levels are shown to be correlated with aldosterone production during exercise, but the mechanism is still unclear. In an in vivo study, male rats were catheterized via right jugular vein (RJV), and divided into four groups namely water immersion, swimming, lactate infusion (13 mg/kg/min) and pyruvate infusion (13 mg/kg/min) groups. Each group was treated for 10 min. Blood samples were collected at 0, 10, 15, 30, 60 and 120 min from RJV after administration. In an in vitro study, rat zona glomerulosa (ZG) cells were challenged by lactate (1-10 mM) in the presence or absence of Ang II (10-8 M) for 60 min. The levels of aldosterone in plasma and medium were measured by radioimmunoassay. Cell lysates were analyzed by immunoblotting assay. After exercise and lactate infusion, plasma levels of aldosterone and lactate were significantly higher than those in the control group. Swimming for 10 min significantly increased the plasma Ang II levels in male rats. Administration of lactate plus Ang II significantly increased aldosterone production and enhanced protein expression of steroidogenic acute regulatory protein (StAR) in ZG cells. These results demonstrated that acute exercise led to the increase of both aldosterone and Ang II secretion, which is associated with lactate action on ZG cells and might be dependent on the activity of renin-angiotensin system.
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DNA microarray reveals ZNF195 and SBF1 are potential biomarkers for gemcitabine sensitivity in head and neck squamous cell carcinoma cell lines.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Gemcitabine is a potential chemotherapy drug for treatment of head and neck squamous cell carcinoma (HNSCC), however, the poor or partial response of HNSCC patients to gemcitabine demonstrated the urgent need for gemcitabine biomarkers to improve the therapy. In present work, 10 HNSCC cell lines were employed to figure out the biomarkers for gemcitabine sensitivity. The sensitivities of these 10 cell lines to gemcitabine and the basal expression of these cell lines was investigated, the correlation between gemcitabine response (IC50 dose) and gene expression was investigated by Pearson correlation and FDR estimation. The top seven positive genes responsible for gemcitabine sensitivity were validated by qPCR in these 10 HNSCC cell lines, while only two genes (SBF1 and ZNF195) were expression-correlated to gemcitabine response. Furthermore, ZNF195 expression was closely associated with gemcitabine sensitivity in the subsequent independent validation in cell lines from various types of cancer. Our work might provide potential biomarkers for gemcitabine sensitivity in HNSCC and various type of cancer.
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Hemokinin-1(4-11)-induced analgesia selectively up-regulates ?-opioid receptor expression in mice.
PLoS ONE
PUBLISHED: 01-01-2014
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Our previous studies have shown that an active fragment of human tachykinins (hHK-1(4-11)) produced an opioid-independent analgesia after intracerebroventricular (i.c.v.) injection in mice, which has been markedly enhanced by a ? OR antagonist, naltrindole hydrochloride (NTI). In this study, we have further characterized the in vivo analgesia after i.c.v. injection of hHK-1(4-11) in mouse model. Our qRT-PCR results showed that the mRNA levels of several ligands and receptors (e.g. PPT-A, PPT-C, KOR, PDYN and PENK) have not changed significantly. Furthermore, neither transcription nor expression of NK1 receptor, MOR and POMC have changed noticeably. In contrast, both mRNA and protein levels of DOR have been up-regulated significantly, indicating that the enhanced expression of ? opioid receptor negatively modulates the analgesia induced by i.c.v. injection of hHK-1(4-11). Additionally, the combinatorial data from our previous and present experiments strongly suggest that the discriminable distribution sites in the central nervous system between hHK-1(4-11) and r/mHK-1 may be attributed to their discriminable analgesic effects. Altogether, our findings will not only contribute to the understanding of the complicated mechanisms regarding the nociceptive modulation of hemokinin-1 as well as its active fragments at supraspinal level, but may also lead to novel pharmacological interventions.
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The interaction effects of pri-let-7a-1 rs10739971 with PGC and ERCC6 gene polymorphisms in gastric cancer and atrophic gastritis.
PLoS ONE
PUBLISHED: 01-01-2014
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The aim of this study was to investigate the interaction effects of pri-let-7a-1 rs10739971 with pepsinogen C (PGC) and excision repair cross complementing group 6 (ERCC6) gene polymorphisms and its association with the risks of gastric cancer and atrophic gastritis. We hoped to identify miRNA polymorphism or a combination of several polymorphisms that could serve as biomarkers for predicting the risk of gastric cancer and its precancerous diseases.
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Effect of proton pump inhibitors on in vitro activity of tigecycline against several common clinical pathogens.
PLoS ONE
PUBLISHED: 01-01-2014
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In this study, we evaluated the effect of proton pump inhibitors (PPIs) on in vitro antimicrobial activity of tigecycline against several species of clinical pathogens. Clinical non-duplicate isolates of Acinetobacter baumannii, Staphylococcus aureus, Enterococcus faecalis and three species of Enterobacteriaceae (Escherichia coli, Klebsiella pneumonia and Enterobacter cloacae) were collected from a tertiary hospital and their MICs of tigecycline alone and in combination with PPIs (omeprazole, lansoprazole and pantoprazole) were determined. With one randomly selected isolate of each bacterial species, an in vitro time-kill study was performed for the confirmation of the effect of PPIs on tigecycline activity. The MIC changes after PPIs addition correlated with the PPIs concentrations in the test media. Compared with tigecycline alone, the addition of 5 mg/L PPIs could increase the MICs of tigecycline by 0 to 2-fold and the addition of 50 mg/L PPIs could increase the MICs of tigecycline by 4 to >128-fold. The time-kill study confirmed that the addition of PPIs could affect the in vitro activity of tigecycline. Even at low concentration (5 mg/L) of omeprazole and pantoprazole, antagonistic effect could be observed in E. cloacae and E. faecalis strains. We conclude that In vitro activity of tigecycline can be influenced by the presence of PPIs in a concentration-dependent manner.
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Structural, Biochemical, and Clinical Characterization of Epidermal Growth Factor Receptor (EGFR) Exon 20 Insertion Mutations in Lung Cancer.
Sci Transl Med
PUBLISHED: 12-20-2013
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Epidermal growth factor receptor (EGFR) gene mutations (G719X, exon 19 deletions/insertions, L858R, and L861Q) predict favorable responses to EGFR tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC). However, EGFR exon 20 insertion mutations (~10% of all EGFR mutations) are generally associated with insensitivity to available TKIs (gefitinib, erlotinib, and afatinib). The basis of this primary resistance is poorly understood. We studied a broad subset of exon 20 insertion mutations, comparing in vitro TKI sensitivity with responses to gefitinib and erlotinib in NSCLC patients, and found that most are resistant to EGFR TKIs. The crystal structure of a representative TKI-insensitive mutant (D770_N771insNPG) reveals an unaltered adenosine triphosphate-binding pocket, and the inserted residues form a wedge at the end of the C helix that promotes the active kinase conformation. Unlike EGFR-L858R, D770_N771insNPG activates EGFR without increasing its affinity for EGFR TKIs. Unexpectedly, we find that EGFR-A763_Y764insFQEA is highly sensitive to EGFR TKIs in vitro, and patients whose NSCLCs harbor this mutation respond to erlotinib. Analysis of the A763_Y764insFQEA mutant indicates that the inserted residues shift the register of the C helix in the N-terminal direction, altering the structure in the region that is also affected by the TKI-sensitive EGFR-L858R. Our studies reveal intricate differences between EGFR mutations, their biology, and their response to EGFR TKIs.
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[Diagnosis and surgical treatment of solitary fibrous tumor of the pelvis].
Beijing Da Xue Xue Bao
PUBLISHED: 12-18-2013
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To explore the clinical diagnosis and surgical treatment of pelvic solitary fibrous tumor (SFT).
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The DNA Repair Gene ERCC6 rs1917799 Polymorphism is Associated with Gastric Cancer Risk in Chinese.
Asian Pac. J. Cancer Prev.
PUBLISHED: 12-03-2013
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Objective: Excision repair cross-complementing group 6 (ERCC6) is a major component of the nucleotide excision repair pathway that plays an important role in maintaining genomic stability and integrity. Several recent studies suggested a link of ERCC6 polymorphisms with susceptibility to various cancers. However, the relation of ERCC6 polymorphism with gastric cancer (GC) risk remains elusive. In this sex- and age- matched case-control study including 402 GC cases and 804 cancer-free controls, we aimed to investigate the association between a potentially functional polymorphism (rs1917799 T>G) in the ERCC6 regulatory region and GC risk. Methods: The genotypes of rs1917799 were determined by Sequenom MassARRAY platform and the status of Helicobacter pylori infection was detected by enzyme-linked immunosorbent assay. Odd ratios (ORs) and 95% confidential interval (CI) were calculated by logistic regression analysis. Results: Compared with the common TT genotype, the ERCC6 rs1917799 GG genotype was associated with increased GC risk (adjusted OR=1.46, 95%CI: 1.03-2.08, P=0.035). When compared with (GT+TT) genotypes, the GG genotype also demonstrated a statistical association with increased GC risk (adjusted OR=1.38, 95%CI: 1.01-1.89, P=0.044). This was also observed for the male subpopulation (GG vs. TT: adjusted OR=1.71, 95%CI: 1.12-2.62, P=0.013; G allele vs. T allele: adjusted OR=1.32, 95%CI: 1.07-1.62, P=0.009). Genetic effects on increased GC risk tended to be enhanced by H. pylori infection, smoking and drinking, but their interaction effects on GC risk did not reach statistical significance. Conclusions: ERCC6 rs1917799 GG genotype might be associated with increased GC risk in Chinese, especially in males.
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[Expression of suppressor of cytokine signaling-3 and caspase-3 in endometriosis and their correlation].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 11-20-2013
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To investigate the expression of suppressor of cytokine signaling(SOCS)-3 and caspase-3 and their correlative significance in endometriosis.
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Menstrual blood-derived mesenchymal stem cells differentiate into functional hepatocyte-like cells.
J Zhejiang Univ Sci B
PUBLISHED: 11-06-2013
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Orthotopic liver transplantation (OLT) is the only proven effective treatment for both end-stage and metabolic liver diseases. Hepatocyte transplantation is a promising alternative for OLT, but the lack of available donor livers has hampered its clinical application. Hepatocyte-like cells (HLCs) differentiated from many multi-potential stem cells can help repair damaged liver tissue. Yet almost suitable cells currently identified for human use are difficult to harvest and involve invasive procedures. Recently, a novel mesenchymal stem cell derived from human menstrual blood (MenSC) has been discovered and obtained easily and repeatedly. In this study, we examined whether the MenSCs are able to differentiate into functional HLCs in vitro. After three weeks of incubation in hepatogenic differentiation medium containing hepatocyte growth factor (HGF), fibroblast growth factor-4 (FGF-4), and oncostain M (OSM), cuboidal HLCs were observed, and cells also expressed hepatocyte-specific marker genes including albumin (ALB), ?-fetoprotein (AFP), cytokeratin 18/19 (CK18/19), and cytochrome P450 1A1/3A4 (CYP1A1/3A4). Differentiated cells further demonstrated in vitro mature hepatocyte functions such as urea synthesis, glycogen storage, and indocyanine green (ICG) uptake. After intrasplenic transplantation into mice with 2/3 partial hepatectomy, the MenSC-derived HLCs were detected in recipient livers and expressed human ALB protein. We also showed that MenSC-derived HLC transplantation could restore the serum ALB level and significantly suppressed transaminase activity of liver injury animals. In conclusion, MenSCs may serve as an ideal, easily accessible source of material for tissue engineering and cell therapy of liver tissues.
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[Cost-effectiveness analysis of HIV testing strategy in hospitals from 2006 to 2010 in Guangzhou].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 10-12-2013
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To evaluate the cost effectiveness of HIV testing strategy in hospitals from 2006 to 2010 in Guangzhou.
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Toxicological effects of multi-walled carbon nanotubes adsorbed with nonylphenol on earthworm Eisenia fetida.
Environ Sci Process Impacts
PUBLISHED: 10-10-2013
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The high surface area of multi-walled carbon nanotubes (MWCNTs) tends to adsorb a large variety of toxic chemicals, which may enhance the toxicity of both MWCNTs and chemicals to organisms. In order to evaluate the combined toxicity of nonylphenol (NP) and MWCNTs to the earthworm Eisenia fetida in soil, artificial soil systems containing distilled water, 0.1 g kg(-1) MWCNTs, 1 g kg(-1) MWCNTs, 1 g kg(-1) MWCNTs absorbed 5 mg kg(-1) NP, and 10 mg kg(-1) NP alone were prepared and exposed to earthworms for 7 days. Antioxidative responses, and activities of cellulase, Na(+), K(+)-ATPase and acetylcholinesterase (TChE) as well as DNA damage were chosen as toxicological endpoints. The results showed that 1 g kg(-1) MWCNTs adsorbed 5 mg kg(-1) NP from the soil which caused much more adverse effects on the earthworms than each chemical alone, evident from the responses of cellulase, Na(+), K(+)-ATPase and comet assay. This study indicated that MWCNTs facilitated the bioavailability of NP to the earthworm and increased the harmful effects of NP.
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The Novel Caspase-3 Substrate Gap43 is Involved in AMPA Receptor Endocytosis and Long-Term Depression.
Mol. Cell Proteomics
PUBLISHED: 09-10-2013
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The cysteine protease caspase-3, best known as an executioner of cell death in apoptosis, also plays a non-apoptotic role in N-methyl-d-aspartate receptor-dependent long-term depression of synaptic transmission (NMDAR-LTD) and ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor endocytosis in neurons. The mechanism by which caspase-3 regulates LTD and AMPA receptor endocytosis, however, remains unclear. Here, we addressed this question by using an enzymatic N-terminal peptide enrichment method and mass spectrometry to identify caspase-3 substrates in neurons. Of the many candidates revealed by this proteomic study, we have confirmed BASP1, Dbn1, and Gap43 as true caspase-3 substrates. Moreover, in hippocampal neurons, Gap43 mutants deficient in caspase-3 cleavage inhibit AMPA receptor endocytosis and LTD. We further demonstrated that Gap43, a protein well-known for its functions in axons, is also localized at postsynaptic sites. Our study has identified Gap43 as a key caspase-3 substrate involved in LTD and AMPA receptor endocytosis, uncovered a novel postsynaptic function for Gap43 and provided new insights into how long-term synaptic depression is induced.
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[A novel immobilized trypsin on hydrophilic polymer modified Silica beads for proteome characterization].
Se Pu
PUBLISHED: 09-10-2013
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A new type of immobilized trypsin was prepared using hydrophilic polymer modified silica microparticles (HPMSM) synthesized by atom transfer radical polymerization (ATRP) as the substrate material. ATRP modification led to densely packed hydrophilic polymer chains grafted on the microparticles surface which resulted in largely increased trypsin loading amount and minimized the nonspecific adsorption of proteins and peptides. Therefore, ultra-fast and highly efficient protein digestion was achieved with minimized sample loss. For standard protein bovine serum albumin (BSA), 1 min digestion led to the identification of 93 peptides, which covered 91% amino acid sequence of the protein. This immobilized trypsin was further successfully applied to the digestion of complex protein samples from yeast and 666 proteins were identified after 3 min digestion, which exceeded the number of identified proteins after 12 h solution digestion.
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Mechanism for activation of mutated epidermal growth factor receptors in lung cancer.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 09-09-2013
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The initiation of epidermal growth factor receptor (EGFR) kinase activity proceeds via an asymmetric dimerization mechanism in which a "donor" tyrosine kinase domain (TKD) contacts an "acceptor" TKD, leading to its activation. In the context of a ligand-induced dimer, identical wild-type EGFR TKDs are thought to assume the donor or acceptor roles in a random manner. Here, we present biochemical reconstitution data demonstrating that activated EGFR mutants found in lung cancer preferentially assume the acceptor role when coexpressed with WT EGFR. Mutated EGFRs show enhanced association with WT EGFR, leading to hyperphosphorylation of the WT counterpart. Mutated EGFRs also hyperphosphorylate the related erythroblastic leukemia viral oncogene (ErbB) family member, ErbB-2, in a similar manner. This directional "superacceptor activity" is particularly pronounced in the drug-resistant L834R/T766M mutant. A 4-Å crystal structure of this mutant in the active conformation reveals an asymmetric dimer interface that is essentially the same as that in WT EGFR. Asymmetric dimer formation induces an allosteric conformational change in the acceptor subunit. Thus, superacceptor activity likely arises simply from a lower energetic cost associated with this conformational change in the mutant EGFR compared with WT, rather than from any structural alteration that impairs the donor role of the mutant. Collectively, these findings define a previously unrecognized mode of mutant-specific intermolecular regulation for ErbB receptors, knowledge of which could potentially be exploited for therapeutic benefit.
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Associations of interleukin-4 receptor gene polymorphisms (Q551R, I50V) with rheumatoid arthritis: evidence from a meta-analysis.
Genet Test Mol Biomarkers
PUBLISHED: 08-24-2013
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Published data on the associations between interleukin-4 receptor (IL-4R) gene polymorphisms (Q551R, I50V) and rheumatoid arthritis (RA) risk are controversial. To quantitatively evaluate the relationships, a meta-analysis was performed.
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Structure-guided inhibitor design expands the scope of analog-sensitive kinase technology.
ACS Chem. Biol.
PUBLISHED: 07-23-2013
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Engineered analog-sensitive (AS) protein kinases have emerged as powerful tools for dissecting phospho-signaling pathways, for elucidating the cellular function of individual kinases, and for deciphering unanticipated effects of clinical therapeutics. A crucial and necessary feature of this technology is a bioorthogonal small molecule that is innocuous toward native cellular systems but potently inhibits the engineered kinase. In order to generalize this method, we sought a molecule capable of targeting divergent AS-kinases. Here we employ X-ray crystallography and medicinal chemistry to unravel the mechanism of current inhibitors and use these insights to design the most potent, selective, and general AS-kinase inhibitors reported to date. We use large-scale kinase inhibitor profiling to characterize the selectivity of these molecules as well as examine the consequences of potential off-target effects in chemical genetic experiments. The molecules reported here will serve as powerful tools in efforts to extend AS-kinase technology to the entire kinome and the principles discovered may help in the design of other engineered enzyme/ligand pairs.
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Next-generation sequencing-based mRNA and microRNA expression profiling analysis revealed pathways involved in the rapid growth of developing culms in Moso bamboo.
BMC Plant Biol.
PUBLISHED: 06-24-2013
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As one of the fastest-growing lignocellulose-abundant plants on Earth, bamboos can reach their final height quickly due to the expansion of individual internodes already present in the buds; however, the molecular processes underlying this phenomenon remain unclear. Moso bamboo (Phyllostachys heterocycla cv. Pubescens) internodes from four different developmental stages and three different internodes within the same stage were used in our study to investigate the molecular processes at the transcriptome and post-transcriptome level.
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IL-10RB rs2834167 (A/G) polymorphism is associated with the susceptibility to systemic lupus erythematosus: evidence from a study in Chinese Han population.
Inflammation
PUBLISHED: 06-11-2013
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Interleukin-10 (IL-10) is a pleiotropic cytokine and plays an important role in the pathogenesis of systemic lupus erythematosus (SLE). Unlike IL-10 protein, few studies have focused on the potential association between IL-10 receptor (IL-10R) and SLE. The purpose of this study was to examine the association of a single nucleotide polymorphism, rs2834167 (A/G), in IL-10R2 gene (IL-10RB) with SLE in a Chinese Han population. A total of 667 patients with SLE and 676 healthy controls were enrolled in the present study. IL-10RB rs2834167 (A/G) polymorphism was specified from genomic DNA using TaqMan genotyping assay on a 7300 real-time reverse transcription polymerase chain reaction system. We found that the frequency of A allele for rs2834167 in patients (44.53 %) was significantly higher than in controls (40.16 %) (? (2) = 5.24, P = 0.022). Allele A was associated with a 1.196-fold (95 % confidence interval (CI), 1.026-1.394) greater risk for the occurrence of SLE compared with the G allele. And both genotypes AG and AA were associated with the susceptibility to SLE as compared with the GG genotype (AG versus GG, odds ratio (OR) = 1.332; 95 %CI, 1.047-1.696; AA versus GG, OR = 1.373; 95 %CI, 1.004-1.878). We also found a statistical significance in the dominant model (AA + AG versus GG, OR = 1.343; 95 %CI, 1.070-1.687). However, no significant evidence for the association of IL-10RB rs2834167 (A/G) polymorphism with any clinical manifestations was detected. Our observations indicate that IL-10RB rs2834167 (A/G) polymorphism may be a potential biomarker for susceptibility to SLE.
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Modified enzyme-linked immunosorbent assay strategy using graphene oxide sheets and gold nanoparticles functionalized with different antibody types.
Anal. Chem.
PUBLISHED: 06-11-2013
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Gold nanoparticles (GNPs) and graphene oxide (GO) sheets are excellent nano carriers in many analytical methods. In this study, a modified enzyme-linked immunosorbent assay (ELISA) strategy was developed using antibody-functionalized GO sheets and GNPs. This modification significantly reduced the limit of detection (LOD) and cost greatly of this assay. The applicability of the method was demonstrated by detecting HSP70 in a human serum sample. This result suggests that the 3G-ELISA method is feasible to detect an antigen in a complex mixture, and the LOD is up to 64-fold and the cost is as low as one-tenth of the conventional ELISA method.
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Regulation of T cell function by the ubiquitin-specific protease USP9X via modulating the Carma1-Bcl10-Malt1 complex.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 05-20-2013
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The ubiquitin conjugation system plays an important role in immune regulation; however, the ubiquitin-specific proteases (USPs) that carry out deubiquitination of cellular substrates are poorly understood. Here we show that in vivo knockdown of the deubiquitinating enzyme USP9X attenuates T-cell proliferation. In addition, naïve CD4(+) T cells from USP9X knockdown chimeric mice display decreased cytokine production and T helper cell differentiation in vitro, which we confirmed in vivo by performing adoptive transfer of transgenic T cells and subsequent immunization. USP9X silencing in both a human T-cell line and mouse primary T cells reduced T-cell receptor (TCR) signaling-induced NF-?B activation. Mechanistically, USP9X interacts with Bcl10 of the Carma1-Bcl10-Malt1 (CBM) complex and removes the TCR-induced ubiquitin chain from Bcl10, which facilitates the association of Carma1 with Bcl0-Malt1. These results demonstrate that USP9X is a crucial positive regulator of the TCR signaling pathway and is required for T-cell function through the modulation of CBM complex formation.
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Different regulatory pathways are involved in the proliferative inhibition of two types of leukemia cell lines induced by paclitaxel.
Oncol. Rep.
PUBLISHED: 05-13-2013
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Paclitaxel, one of the broadest-spectrum anticancer agents, is currently being used in the treatment of patients with solid tumors. In the present study, we compared the effect of paclitaxel on two types of leukemia cells. Our results showed that paclitaxel could inhibit the proliferation of MEL and K562 cells in a dose- and time-dependent manner. The mechanism of proliferative inhibition in K562 cells treated by paclitaxel was related to the cell cycle arrest in the G2/M phase, as well as the induction of apoptosis. By contrast, MEL cells treated by paclitaxel showed significant characteristics of necrosis, which indicated that the mode of cell death induced by paclitaxel in these two types of leukemia cells differed. Advances in research of the cell cycle, apoptosis and necrosis will extend our understanding of the mechanisms of paclitaxel-induced cell death, particularly in leukemia cells. Further elucidation of the mechanisms of necrosis in MEL cells may expedite the development of improved paclitaxel-based regimens for cancer therapy.
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[cDNA cloning and sequence analysis of pluripotency genes in tree shrews (Tupaia belangeri)].
Zool. Res.
PUBLISHED: 04-11-2013
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In this paper, partial sequences of the tree shrew (Tupaia belangeri) Klf4, Sox2, and c-Myc genes were cloned and sequenced, which were 382, 612, and 485 bp in length and encoded 127, 204, and 161 amino acids, respectively. Whereas, their cDNA sequence identities with those of human were 89%, 98%, and 89%, respectively. Their phylogenetic tree results indicated different topologies and suggested individual evolutional pathways. These results can facilitate further functional studies.
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Proteomic characterization of larval and adult developmental stages in Echinococcus granulosus reveals novel insight into host-parasite interactions.
J Proteomics
PUBLISHED: 04-08-2013
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Cystic hydatid disease is an important zoonosis caused by Echinococcus granulosus infection. The expression profiles of its parasitic life stages and host-Echinococcus interactions remain to be elucidated. Here, we identified 157 adult and 1588 protoscolex proteins (1610 in all), including 1290 novel identifications. Paramyosins and an antigen B (AgB) were the dominant adult proteins. Dog proteins (30) identified in adults indicated diminished local inflammation caused by adult infection. The protoscolex expresses proteins that have been reported to be antigens in other parasites, such as 6-phosphofructokinase and calcineurin B. Pathway analyses suggested that E. granulosus uses both aerobic and anaerobic carbohydrate metabolisms to generate ATP. E. granulosus expresses proteins involved in synthesis and metabolism of lipids or steroids. At least 339 of 390 sheep proteins identified in protoscolex were novel identifications not seen in previous analyses. IgGs and lambda light chains were the most abundant antibody species. Sheep proteins were enriched for detoxification pathways, implying that host detoxification effects play a central role during host-parasite interactions. Our study provides valuable data on E. granulosus expression characteristics, allowing novel insights into the molecular mechanisms involved in host-parasite interactions.
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In vitro effects of tigecycline in combination with colistin (polymyxin E) and sulbactam against multidrug-resistant Acinetobacter baumannii.
J. Antibiot.
PUBLISHED: 04-06-2013
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The lack of active antimicrobial agents against multidrug-resistant (MDR) Acinetobacter baumannii has posed great threat to the public health. Combination therapies with antibiotics owning different antimicrobial mechanisms have been proposed as good options for treating MDR A. baumannii infections. This study was aimed to investigate the in vitro effects of tigecycline in combination with colistin and sulbactam against MDR A. baumannii. A total of 70 strains from two hospitals in China were examined in the study. The checkerboard method was used for determining synergistic activity of different antibiotic combinations. Tigecycline/colistin combination displayed synergistic and partial synergistic activity in 24.3% of the isolates, whereas the tigecycline/sulbactam combination showed synergistic and partial synergistic activity in 64.3% of the isolates. Neither of the combinations showed antagonism in this study. In addition, for evaluating the ability of combinations on resistance prevention, mutant prevention concentrations (MPCs) of tigecycline, colistin, sulbactam alone and tigecycline in combination with colistin and sulbactam were studied against MDR A. baumannii. Compared with tigecycline used alone, combination therapies could achieve lower MPCs of tigecycline. However, when the MPCs of dual-drug therapy were in conjunction with clinical pharmacokinetic profiles, combinations may not strictly curb the occurrence of resistance at current dosage regimen. In summary, this study suggested that combination therapy was a good option for treating MDR A. baumannii infections. But the finding that combination with these drugs at current dosage regimen may not prevent emergence of resistance warranted further studies on dosage of combined antibiotics required for achieving resistance prevention.
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Usp18 deficient mammary epithelial cells create an antitumour environment driven by hypersensitivity to IFN-? and elevated secretion of Cxcl10.
EMBO Mol Med
PUBLISHED: 04-04-2013
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The theory of cancer immunoediting refers to mechanisms by which the immune system can suppress or promote tumour progression. A major challenge for the development of novel cancer immunotherapies is to find ways to exploit the immune systems antitumour activity while concomitantly reducing its protumour activity. Using the PyVmT model of mammary tumourigenesis, we show that lack of the Usp18 gene significantly inhibits tumour growth by creating a tumour-suppressive microenvironment. Generation of this antitumour environment is driven by elevated secretion of the potent T-cell chemoattractant Cxcl10 by Usp18 deficient mammary epithelial cells (MECs), which leads to recruitment of Th1 subtype CD4(+) T cells. Furthermore, we show that Cxcl10 upregulation in MECs is promoted by interferon-? and that Usp18 is a novel inhibitor of interferon-? signalling. Knockdown of the interferon-? specific receptor subunit IL-28R1 in Usp18 deficient MECs dramatically enhances tumour growth. Taken together, our data suggest that targeting Usp18 may be a viable approach to boost antitumour immunity while suppressing the protumour activity of the immune system.
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The co-expression of functional gastric proteins in dynamic gastric diseases and its clinical significance.
BMC Clin Pathol
PUBLISHED: 04-03-2013
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Pepsinogen C (PGC) and mucin1 (MUC1) are important physiologically functional gastric proteins; Mucin2 (MUC2) is an "ectopic" functional protein in intestinal metaplasia of gastric mucosa. We analyzed the co-expression of the above-mentioned three proteins in dynamic gastric diseases {superficial gastritis (SG)-atrophic gastritis (AG)--gastric cancer (GC)} as well as different histological types of gastric cancer in order to find molecular phenotypes of gastric cancer and precancerous disease and further explore the potential co-function of PGC, MUC1 and MUC2 in the occurrence and development of gastric cancer.
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Development and validation of a highly sensitive LC-MS/MS method for quantitation of bivalirudin in human plasma: application to a human pharmacokinetic study.
Biomed. Chromatogr.
PUBLISHED: 03-18-2013
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A sensitive, specific and simple LC-MS/MS method was developed for the identification and quantification of bivalirudin in human plasma using diazepam as an internal standard (IS). The API-4000 LC-MS/MS was operated under multiple-reaction monitoring mode using electrospray ionization. The sample preparation consisted of an easy protein precipitation sample pretreatment with methanol. Chromatographic separation was achieved on a Zorbax Eclipse plus C18 100?×?2.1?mm column with a mobile phase of water-methanol-0.1% formic acid. The analytes were detected with a triple quadrupole Quantum Access with positive ionization. Ions monitored in the multiple-reaction monitoring mode were m/z 1091???650 for bivalirudin (at 2.70?min) and m/z 285???193 for diazepam (at 3.85?min). The developed method was validated in human plasma with a lower limit of quantitation of 20?µg/L for bivalirudin. A linear response function was established for the range of concentrations 20-10,000?µg/L (r?>?0.998) for bivalirudin. The intra- and inter-day precision values for bivalirudin met the acceptance criteria as per US Food and Drug Administration guidelines. Bivalirudin was stable in the battery of stability studies, viz. bench-top, freeze-thaw cycles and long-term stability. The developed assay method was applied to an intravenous administration study in humans. Copyright © 2013 John Wiley & Sons, Ltd.
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Expression of serum miR-20a-5p, let-7a, and miR-320a and their correlations with pepsinogen in atrophic gastritis and gastric cancer: a case-control study.
BMC Clin Pathol
PUBLISHED: 03-18-2013
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The identification of serial miRNAs targeting the same functional gastric protein could provide new and effective serological biomarkers for the diagnosis of gastric cancer (GC). The aim of this study was to evaluate the potential of miR-20a-5p, let-7a and miR-320a in the diagnosis of AG or GC and the correlation of the three miRNAs with their predicted target molecules PGA, PGC and PGA/PGC ratio.
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TSC1 regulates the balance between effector and regulatory T cells.
J. Clin. Invest.
PUBLISHED: 03-08-2013
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Mammalian target of rapamycin (mTOR) plays a crucial role in the control of T cell fate determination; however, the precise regulatory mechanism of the mTOR pathway is not fully understood. We found that T cell-specific deletion of the gene encoding tuberous sclerosis 1 (TSC1), an upstream negative regulator of mTOR, resulted in augmented Th1 and Th17 differentiation and led to severe intestinal inflammation in a colitis model. Conditional Tsc1 deletion in Tregs impaired their suppressive activity and expression of the Treg marker Foxp3 and resulted in increased IL-17 production under inflammatory conditions. A fate-mapping study revealed that Tsc1-null Tregs that lost Foxp3 expression gained a stronger effector-like phenotype compared with Tsc1-/- Foxp3+ Tregs. Elevated IL-17 production in Tsc1-/- Treg cells was reversed by in vivo knockdown of the mTOR target S6K1. Moreover, IL-17 production was enhanced by Treg-specific double deletion of Tsc1 and Foxo3a. Collectively, these studies suggest that TSC1 acts as an important checkpoint for maintaining immune homeostasis by regulating cell fate determination.
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Blast effect on the lower extremities and its mitigation: a computational study.
J Mech Behav Biomed Mater
PUBLISHED: 03-07-2013
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A series of computational studies were performed to investigate the response of the lower extremities of mounted soldiers under landmine detonation. A numerical human body model newly developed at Wayne State University was used to simulate two types of experimental studies and the model predictions were validated against test data in terms of the tibia axial force as well as bone fracture pattern. Based on the validated model, the minimum axial force causing tibia facture was found. Then a series of parametric studies was conducted to determine the critical velocity (peak velocity of the floor plate) causing tibia fracture at different upper/lower leg angles. In addition, to limit the load transmission through the vehicular floor, two types of energy absorbing materials, namely IMPAXX(®) foam and aluminum alloy honeycomb, were selected for floor matting. Their performances in terms of blast effect mitigation were compared using the validated numerical model, and it has been found that honeycomb is a more efficient material for blast injury prevention under the loading conditions studied.
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Promoter polymorphisms in trefoil factor 2 and trefoil factor 3 genes and susceptibility to gastric cancer and atrophic gastritis among Chinese population.
Gene
PUBLISHED: 03-05-2013
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The polymorphisms in trefoil factor (TFF) gene family that protect gastrointestinal epithelium might influence individual vulnerability to gastric cancer (GC) and atrophic gastritis. We used the Sequenom MassARRAY platform to identify the genotypes of TFF2 rs3814896 and TFF3 rs9981660 polymorphisms in 478 GC patients, 652 atrophic gastritis patients, and 724 controls. For the TFF2 rs3814896 polymorphism, in the subgroup aged ? 50 years, we found that AG+GG genotypes were associated with a 0.746-fold decreased risk of atrophic gastritis [p=0.023, 95% confidence interval (CI)=0.580-0.960], a 0.626-fold decreased risk of GC (p=0.005, 95% CI=0.451-0.868), and a 0.663-fold decreased risk of diffuse-type GC (p=0.034, 95% CI=0.452-0.970) compared with the common AA genotype. For the TFF3 rs9981660 polymorphism, in the male subgroup, individuals with variant AG+AA genotype were associated with a 0.761-fold decreased risk of diffuse-type GC compared with the common GG genotype (p=0.043, 95% CI=0.584-0.992). Additionally, we found that in subjects aged ? 50 years compared with common AA genotype, TFF2 rs3814896 AG+GG genotypes were associated with increased TFF2 mRNA levels in the total gastric cancer specimens and in the diffuse-type gastric cancer specimens; and in males aged ? 50 years compared with common GG genotype, TFF3 rs9981660 AA+AG genotypes were associated with TFF3 mRNA levels in diffuse-type gastric cancer tissues and their corresponding non-cancerous tissues. To our knowledge, this is the first report of an association between the TFF2 rs3814896 AG+GG genotypes and decreased risks of GC, diffuse-type GC, and atrophic gastritis in younger people aged ? 50 years, and an association between TFF3 rs9981660 AG+AA genotype and decreased risk of diffuse-type GC in men. Moreover, we found that TFF2 rs3814896 AG+GG genotypes in people aged ? 50 years and TFF3 rs9981660 AG+AA genotypes in younger males with diffuse-type GC were associated with higher levels of TFF2 and TFF3 mRNA respectively.
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Equilibrium and kinetic studies of phosphate removal from solution onto a hydrothermally modified oyster shell material.
PLoS ONE
PUBLISHED: 02-24-2013
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Phosphate removal to a hydrothermally modified fumed silica and pulverized oyster shell material for use in wastewater treatments were made. Sorption data modeling (pHs 3-11, P concentrations of 3, 5, 10, 15, 20, & 25 mg/L, and at an ambient temperature of 23°C) indicate that an optimal removal of P occurs at pH 11. Three kinetic models were also applied (a pseudo-first-order Lagergren kinetic model, a pseudo-second-order (PSO) kinetic and Elovich) and indicate that a PSO model best describes P-removal. In addition, an application of the Weber and Morris intra-particle diffusion model indicates that external mass transfer and intra-particle diffusion were both involved in the rate-determining step. Langmuir, Freundlich modeling of the sorption data also indicate that the heterogeneous Freundlich sorption site model best describes the data although Langmuir data also fit with data tailing suggesting data are not linear. The data collected indicates that the hydrothermally modified fumed silica and pulverized oyster shell material is suitable for use in wastewater treatment, with P-removal to the solids being preferential and spontaneous.
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Novel cytotoxic exhibition mode of antimicrobial peptide anoplin in MEL cells, the cell line of murine Friend leukemia virus-induced leukemic cells.
J. Pept. Sci.
PUBLISHED: 02-14-2013
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Anoplin is a recently discovered antimicrobial peptide (AMP) isolated from the venom sac of the spider wasp Anoplius samariensis, and it is one of the shortest ?-helical AMP found naturally to date consisting of only ten amino acids. Previous results showed that anoplin exhibits potent antimicrobial activity but little hemolytic activity. In this study, we synthesized anoplin, studied its cytotoxicity in Friend virus-induced leukemia cells [murine erythroleukemia (MEL) cells], and proposed its possible mechanism. Our results showed that anoplin could inhibit the proliferation of MEL cells in a dose-dependent and time-dependent manner via disrupting the integrity of cell membrane, which indicated that anoplin exerts its cytotoxicity efficacy. In addition, the cell cycle distribution of MEL cells was arrested in the G?/G? phase significantly. However, anoplin could not induce obvious apoptosis in MEL cells, as well as anoplin could not induce visible changes on morphology and quantity in the bone marrow cells isolated from normal mice. All of these results indicate that anoplin, as generally believed, is a selective AMP, a value characteristic in the design of safe therapeutic agents. The cytotoxicity of anoplin on MEL cells was mainly attributable to the plasma membrane perturbation and also to the intracellular events such as the arrest of cell cycle. Although this is an initial study that explored the activity of anoplin in vitro rather than in vivo, with the increasing resistance of conventional chemotherapy, there is no doubt that anoplin has desirable feature to be developed as a novel and selective anticancer agent.
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Itch expression by Treg cells controls Th2 inflammatory responses.
J. Clin. Invest.
PUBLISHED: 02-13-2013
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Regulatory T (Treg) cells maintain immune homeostasis by limiting autoimmune and inflammatory responses. Treg differentiation, maintenance, and function are controlled by the transcription factor Foxp3. However, the exact molecular mechanisms underlying Treg cell regulation remain elusive. Here, we show that Treg cell-specific ablation of the E3 ubiquitin ligase Itch in mice caused massive multiorgan lymphocyte infiltration and skin lesions, chronic T cell activation, and the development of severe antigen-induced airway inflammation. Surprisingly, Foxp3 expression, homeostasis, and the in vitro and in vivo suppressive capability of Treg cells were not affected by Itch deficiency. We found that the expression of Th2 cytokines by Treg cells was increased in the absence of Itch. Fate mapping revealed that a fraction of Treg cells lost Foxp3 expression independently of Itch. However, Th2 cytokines were excessively augmented in Itch-/- Foxp3-negative "ex-Treg" cells without altering the percentage of conversion. Targeted knockdown of Th2 transcriptional regulators in Itch-/- Treg cells prevented Th2 cytokine production. The present study unveils a mechanism of Treg cell acquisition of Th2-like properties that is independent of Foxp3 function and Treg cell stability.
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Heterogeneous catalysts need not be so "heterogeneous": monodisperse Pt nanocrystals by combining shape-controlled synthesis and purification by colloidal recrystallization.
J. Am. Chem. Soc.
PUBLISHED: 02-08-2013
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Well-defined surfaces of Pt have been extensively studied for various catalytic processes. However, industrial catalysts are mostly composed of fine particles (e.g., nanocrystals), due to the desire for a high surface to volume ratio. Therefore, it is very important to explore and understand the catalytic processes both at nanoscale and on extended surfaces. In this report, a general synthetic method is described to prepare Pt nanocrystals with various morphologies. The synthesized Pt nanocrystals are further purified by exploiting the "self-cleaning" effect which results from the "colloidal recrystallization" of Pt supercrystals. The resulting high-purity nanocrystals enable the direct comparison of the reactivity of the {111} and {100} facets for important catalytic reactions. With these high-purity Pt nanocrystals, we have made several observations: Pt octahedra show higher poisoning tolerance in the electrooxidation of formic acid than Pt cubes; the oxidation of CO on Pt nanocrystals is structure insensitive when the partial pressure ratio p(O2)/p(CO) is close to or less than 0.5, while it is structure sensitive in the O(2)-rich environment; Pt octahedra have a lower activation energy than Pt cubes when catalyzing the electron transfer reaction between hexacyanoferrate (III) and thiosulfate ions. Through electrocatalysis, gas-phase-catalysis of CO oxidation, and a liquid-phase-catalysis of electron transfer reaction, we demonstrate that high quality Pt nanocrystals which have {111} and {100} facets selectively expose are ideal model materials to study catalysis at nanoscale.
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A coordinated proteomic approach for identifying proteins that interact with the E. coli ribosomal protein S12.
J. Proteome Res.
PUBLISHED: 02-01-2013
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The bacterial ribosomal protein S12 contains a universally conserved D88 residue on a loop region thought to be critically involved in translation due to its proximal location to the A site of the 30S subunit. While D88 mutants are lethal this residue has been found to be post-translationally modified to ?-methylthioaspartic acid, a post-translational modification (PTM) identified in S12 orthologs from several phylogenetically distinct bacteria. In a previous report focused on characterizing this PTM, our results provided evidence that this conserved loop region might be involved in forming multiple proteins-protein interactions ( Strader , M. B. ; Costantino , N. ; Elkins , C. A. ; Chen , C. Y. ; Patel , I. ; Makusky , A. J. ; Choy , J. S. ; Court , D. L. ; Markey , S. P. ; Kowalak , J. A. A proteomic and transcriptomic approach reveals new insight into betamethylthiolation of Escherichia coli ribosomal protein S12. Mol. Cell. Proteomics 2011 , 10 , M110 005199 ). To follow-up on this study, the D88 containing loop was probed to identify candidate binders employing a two-step complementary affinity purification strategy. The first involved an endogenously expressed S12 protein containing a C-terminal tag for capturing S12 binding partners. The second strategy utilized a synthetic biotinylated peptide representing the D88 conserved loop region for capturing S12 loop interaction partners. Captured proteins from both approaches were detected by utilizing SDS-PAGE and one-dimensional liquid chromatography-tandem mass spectrometry. The results presented in this report revealed proteins that form direct interactions with the 30S subunit and elucidated which are likely to interact with S12. In addition, we provide evidence that two proteins involved in regulating ribosome and/or mRNA transcript levels under stress conditions, RNase R and Hfq, form direct interactions with the S12 conserved loop, suggesting that it is likely part of a protein binding interface.
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Weight-adjusted versus fixed dose of linezolid for Chinese healthy volunteers of higher and lower body weight: a Phase I pharmacokinetic and pharmacodynamic study.
Expert Opin Investig Drugs
PUBLISHED: 01-30-2013
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The objective was to evaluate the pharmacokinetic and pharmacodynamic properties of a single intravenous fixed dose compared with a weight-adjusted dose of linezolid.
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Study on the distribution sites and the molecular mechanism of analgesia after intracerebroventricular injection of rat/mouse hemokinin-1 in mice.
Peptides
PUBLISHED: 01-29-2013
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Hemokinin-1 is a peptide encoded by Pptc, which belongs to the family of mammalian tachykinins. Our previous results showed that rat/mouse hemokinin-1 (r/m HK-1) produced striking analgesia after intracerebroventricular (i.c.v.) injection in mice, and the analgesia could be blocked by the NK1 receptor antagonist and the opioid receptor antagonist, respectively. However, the precise distribution sites and the molecular mechanism involved in the analgesic effect after i.c.v. administration of r/m HK-1 are needed to be further investigated deeply. Using the fluorescence labeling method, our present results directly showed that r/m HK-1 peptides were mainly distributed at the ventricular walls and several juxta-ventricular structures for the first time. Our results showed that the mRNA expressions of NK1 receptor, PPT-A, PPT-C, KOR, PDYN, DOR and PENK were not changed markedly, as well as the protein expression of NK1 receptor was hardly changed. However, both the transcripts and proteins of MOR and POMC were up-regulated significantly, indicating that the analgesic effect induced by i.c.v. administration of r/m HK-1 is related to the activation of NK1 receptor first, then it is related to the release of endogenous proopiomelanocortin, as well as the increased expression level of ? opioid receptor. These results should facilitate further the analysis of the analgesia of r/m HK-1 in the central nerval system in acute pain and may open novel pharmacological interventions.
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