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Synthesis and Effect on Human HepG2 Cells of 1,2-bis- (2-Methylallyl)disulfane

Chunxiao Ji, Fenglian Ren, Jun Dai, Ming Xu
2010 Molecules  
1,2-bis(2-methylallyl)disulfane was synthesized from sodium sulfide and 3-chloro-2-methylpropylene. The structure of the target product was confirmed by GC-MS, 1H-NMR and elemental analysis.  ...  Cell viability assay, flow-cytometric analysis and protein expression results showed that 1,2-bis(2-methylallyl)disulfane could significantly inhibit the proliferation, and induce the apoptosis of human  ...  of 1,2-bis(2-methylallyl)disulfane.  ... 
doi:10.3390/molecules15053634 pmid:20657504 pmcid:PMC6263348 fatcat:slynw3d5zzc7jbxitaisa5uhjm

CHST6-related macular corneal dystrophy: a matter of endothelium [article]

Bi Ning Zhang, Benxiang Qi, Xin Wang, Chunxiao Dong, Jun Cheng, Dewei Li, Suxia Li, Min Chen, Bin Zhang, Qingjun Zhou, Lixin Xie
2021 medRxiv   pre-print
Macular corneal dystrophy (MCD) is classified as corneal stromal dystrophy. In this study, we retrospectively reviewed the surgical outcomes of 118 MCD patients receiving surgical treatment in the past 30 years and found patients receiving penetrating keratoplasty had the lowest recurrence rate 13.75%, compared with 40.91% patients receiving deep anterior lamellar keratoplasty and 25% receiving phototherapeutic keratectomy. Transcriptomic analysis in human corneal single-cell sequencing atlas
more » ... und the MCD pathogenic gene CHST6 was abundant in corneal endothelium rather than other cell types. CHST6 protein showed a similar expression pattern to its mRNA. The mouse homologous gene Chst5 was 120-fold higher in corneal endothelium than in the epithelial and stromal layers. Mice with specifically Chst5 knockdown in the endothelial layer by microinjection of the adeno-associated virus serotype 9 - shRNA plasmids into the anterior chamber, rather than Chst5 knockdown into the stroma, showed MCD-like phenotypes. Corneal opacification and abnormally larger collagen fibrils were observed in the endothelial Chst5 knockdown mice. The same corneal characteristics were observed after overexpressing human CHST6 mutant R50H in the mouse endothelium. These observations indicating the pathogenesis of MCD is more related to the corneal endothelium rather than the stroma.
doi:10.1101/2021.05.31.21258099 fatcat:xpqxmcckcfcbtmjgx55vksej7a

Dynamics of endogenous endothelial progenitor cells homing modulated by physiological ischaemia training

Chunxiao Wan, Jianan Li, Chengjian Yang, Dayi Hu, Sheng Bi
2015 Journal of Rehabilitation Medicine  
To locate and trace endogenous endothelial progenitor cells (EPCs) in rabbits subjected to myocardial ischaemia and/or physiological ischaemia training. Rabbits were randomly divided into 4 groups: a myocardial ischaemia group (subjected to myocardial ischaemia only); a physiological ischaemia training group (subjected to physiological ischaemia training only); a physiological ischaemia training-myocardial ischaemia group (subjected to both myocardial ischaemia and physiological ischaemia
more » ... ng); and a sham-operated group. Myocardial ischaemia was induced experimentally by a 2-min ischaemia, followed by a 1-h reperfusion. Physiological ischaemia training involved a 4-min isometric contraction elicited by electrical stimulation (biphase square wave, 40 Hz, 1 ms), which generated a contraction force at 40% of the maximal isometric contraction force. Myocardial ischaemia I and/or physiological ischaemia training were performed twice a day, 5 days a week for 4 weeks. Capillary densities and EPC levels in both blood and the ischaemic heart region were then measured. EPCs were traced by double-labelling with super paramagnetic iron oxide and chloromethyl-benzamidodialkylcarbocyanine. EPC levels in the blood and the ischaemic heart region both improved significantly in the physiological ischaemia training-myocardial ischaemia group (mean 0.046% (standard deviation (SD) 0.007), 0.013% (SD 0.005)) and group myocardial ischaemia (mean 0.038% (SD 0.016), 0.008% (SD 0.004)). For the physiological ischaemia training group, moderately raised EPCs were found in the blood (0.026 ± 0.010%), but not in the heart. Capillary density increased in the physiological ischaemia training-myocardial ischaemia and myocardial ischaemia groups. The dual-labelled EPCs were confirmed in the ischaemic heart region. Pearson's analysis demonstrated that there is a positive correlation between EPC levels in the blood and the heart region (p < 0.05), and between circulating EPCs and the capillary (p < 0.05) for the physiological ischaemia training-myocardial ischaemia group. Physiological ischaemia training can effectively improve endogenous EPCs. Their homing process from the circulating blood to the ischaemic myocardium was clearly traced in this study on rabbits. This homing process is of great importance for remote neovascularization.
doi:10.2340/16501977-1891 pmid:25224020 fatcat:ab2ic2ev65eina3fyrobj4nnda

Dendritic cell MST1 inhibits Th17 differentiation

Chunxiao Li, Yujing Bi, Yan Li, Hui Yang, Qing Yu, Jian Wang, Yu Wang, Huilin Su, Anna Jia, Ying Hu, Linian Han, Jiangyuan Zhang (+3 others)
2017 Nature Communications  
In this study, the authors analyze the role of MST1 in dendritic cells (DCs) in the regulation of CD4 T cell responses. Mice containing a DC-specific deletion of MST1 generate enhanced Th17 responses in several settings. The authors identify increased expression of IL-6 in MST1-deficient DCs as the driver of this enhancement and link the increase of IL-6 to a better phosphorylation of p38. This study therefore identifies MST1 in DCs as a negative regulator that controls the generation of Th17
more » ... sponses. In recent years, MST1 has received considerable attention. Despite this interest, the role of MST1 in bridging innate and adaptive immunity has remained poorly understood. The current study is timely as it explores this aspect in vivo, using an elegant mouse model. In addition, the study dissects the role of MST1 in this process in a thorough manner. Based on these strengths, it should be considered for publication in Nature Communications. However, the study also shows some weaknesses that should be addressed first: Main points: A) Many of the experiments are superficially described and the experimental conditions are often unclear. Moreover, the language is poor. These craftsmanship issues make it at time difficult to evaluate the experiments and results properly. B) Along the same lines, the authors present the adoptive T cell experiments (page 11) but neither mention the number of transferred T cells in the main body of the text nor in the figure legend or material and methods. The transfer of a high number of transgenic T cells is not physiological and can lead to experimental artefacts, which is particularly true for innate signaling molecules such as IL-6. This issue could be easily addressed by measuring the endogenous CD4 T cell response following MOG or OVA/CFA immunization and subsequent restimulation ex vivo with protein in the presence of irradiated splenocytes and subsequent ELISA (this antigen-specific approach would also control for possible by-stander effects that can occur upon re-stimulation with PMA/ionomycin). C) The authors propose increased production of IL-6 by MST1-deficient DCs as the mechanism for the enhanced Th17 response. The presented data are indeed suggestive of this interpretation. However, this interpretation fails to account for the possibility that MST1 also controls other aspects of the DC response. The manipulation of IL-6 production by DCs or IL-6 signaling in T cells (Fig. 6-7 ) is somewhat unsatisfying because it automatically affects Th17 differentiation since IL-6 is required for Th17 differentiation itself. This caveat is underscored by the observation that even in IL-6-deficient DCs, MST1 has an effect on Th17 differentiation (Fig. 6D ). Moreover, the authors propose an IL-6-dependent feed-forward loop that leads to increased IL-6R expression on CD4 T cells and phosphorylation of STAT3 (Fig. S11-12 ). If MST1 indeed controls Th17 differentiation by using IL-6 as a dial, then IL-6R downregulation in T cells should also affect the Th17 levels in cocultures with WT DCs. It does not. In light of these observations, the authors should attempt to strengthen the rationale for IL-6 as the major MST1-dependent control mechanism: 1) The authors only measure the production of the classic Th17 cytokines IL-6, IL-1, IL-23, and TGFb, of which only IL-6 expression is enhanced in the absence of MST1. What about other cytokines or factors? What about other aspects of DC biology, e. g. apoptosis? 2) Why do WT DCs induce pSTAT3 as effectively in CD4 T cells with reduced IL-6R expression as in WT CD4 T cells (Fig. S11 -12)? Is this an effect that depends on the dose of IL-6? Perhaps a titration of IL-6 may help here.
doi:10.1038/ncomms14275 pmid:28145433 pmcid:PMC5296641 fatcat:vanphhpilnbthbhrg3d7vsttri

Will Widgets and Semantic Tagging Change Computational Biology?

Philip E. Bourne, Bojan Beran, Chunxiao Bi, Wolfgang Bluhm, Roland Dunbrack, Andreas Prlić, Greg Quinn, Peter Rose, Raship Shah, Wendy Tao, Brian Weitzner, Ben Yukich (+1 others)
2010 PLoS Computational Biology  
doi:10.1371/journal.pcbi.1000673 pmid:20195550 pmcid:PMC2829027 fatcat:76skg5obdnahvotjzf4jandbui

Synthesis and biological activity of bi/tricyclic azasugars fused thiazolidin-4-one and thiazinan-4-one by microwave-assisted tandem Staudinger/aza-Wittig/cyclization

Xiaoliu Li, Zhanbin Qin, Tianyu Yang, Hongzhi Zhang, Sinan Wei, Chunxiao Li, Hua Chen, Ming Meng
2012 Bioorganic & Medicinal Chemistry Letters  
The reactions were carried out with the azidosugar 1 and mercaptan acids via a key intermediate Schiff base and stereoselectively afforded the titled bi/tricyclic azasugars in good yield.  ...  A convenient synthesis of novel bi/tricyclic azasugars fused thiazolidin-4-one and thiazinan-4-one by the one-pot tandem Staudinger/aza-Wittig/cyclization reaction under microwave radiation was demonstrated  ...  in good yield and stereoselectivity, providing a convenient method for constructing such bi/tricyclic azasugars based on Schiff base.  ... 
doi:10.1016/j.bmcl.2012.02.103 pmid:22437112 fatcat:3pu3x5r2rncrhheszewkcypjue

The next generation RCSB.org

Justin Flatt, Jose M. Duarte, Charmi Bhikadiya, Chunxiao Bi, Sebastian Bittrich, Li Chen, Shuchismita Dutta, Robert Lowe, Alexander S. Rose, Yana Rose, Joan Segura, John Westbrook (+1 others)
2021 Acta Crystallographica Section A: Foundations and Advances  
doi:10.1107/s0108767321097245 fatcat:a4cblmwfejdfvmtsdxkcvhnwve

BioJava-ModFinder: identification of protein modifications in 3D structures from the Protein Data Bank

Jianjiong Gao, Andreas Prlić, Chunxiao Bi, Wolfgang F Bluhm, Dimitris Dimitropoulos, Dong Xu, Philip E Bourne, Peter W Rose, Alfonso Valencia
2017 Bioinformatics  
We developed a new software tool, BioJava-ModFinder, for identifying protein modifications observed in 3D structures archived in the Protein Data Bank (PDB). Information on more than 400 types of protein modifications were collected and curated from annotations in PDB, RESID, and PSI-MOD. We divided these modifications into three categories: modified residues, attachment modifications, and cross-links. We have developed a systematic method to identify these modifications in 3D protein
more » ... . We have integrated this package with the RCSB PDB web application and added protein modification annotations to the sequence diagram and structure display. By scanning all 3D structures in the PDB using BioJava-ModFinder, we identified more than 30 000 structures with protein modifications, which can be searched, browsed, and visualized on the RCSB PDB website. Availability and Implementation: BioJava-ModFinder is available as open source (LGPL license) at
doi:10.1093/bioinformatics/btx101 pmid:28334105 pmcid:PMC5870676 fatcat:7xuhkcsn5jhcrjmqakp74k4u7y

Normal-state Nernst effect from bidirectional bond density wave state in high-Tccuprates

Girish Sharma, Chunxiao Liu, Kangjun Seo, J. D. Sau, Sumanta Tewari
2015 Physical Review B  
The role of charge order in the phase diagram of high temperature cuprate superconductors has been recently re-emphasized by the experimental discovery of an incipient bi-directional charge density wave  ...  Here we take a mean field Q_1=(2\pi/3,0) and Q_2=(0,2\pi/3) bi-directional BDW phase with a d-wave form factor, which closely resembles the experimentally observed charge ordered states in underdoped cuprates  ...  Electron spectral function A(ω = 0, k) in the presence of bi-directional bond order Q1 = (2π/3, 0) and Q2 = (0, 2π/3) at a doping value of p = 10%.  ... 
doi:10.1103/physrevb.92.155114 fatcat:n7mbzfueb5edrmgqtla5unjzjq

RCSB PDB next-generation data delivery and search services

Christine Zardecki, Jose M. Duarte, Chunxiao Bi, Charmi Bhikadiya, Sebastian Bittrich, Li Chen, Dmytro Guzenko, Robert Lowe, Joan Segura, Yana Valasatava, John Westbrook, Stephen Burley
2020 Acta Crystallographica Section A: Foundations and Advances  
RCSB Protein Data Bank (PDB) provides tools for analysis and visualization of 3D structures of biological macromolecules stored in the PDB archive. Recently-introduced Search and Data Delivery APIs offer comprehensive functionality and high performance at RCSB.org. The new services represent a complete overhaul of the software/data management architecture, transforming a monolithic application into a micro-service-oriented and cloud-ready resource. The data model is based on the PDBx/mmCIF
more » ... onary (http://mmcif.wwpdb.org/) with extensions that facilitate usage and delivery for the RCSB PDB website and web services. For Data delivery (https://data.rcsb.org), a GraphQL interface allows arbitrary retrieval of data across the entire data model. To the best of our knowledge, this represents a first in Structural Bioinformatics. Search services (https://search.rcsb.org) are supported by a powerful Search API with a JSON-based Domain Specific Language (DSL). Arbitrary boolean logic search is now possible across all fields available in our data model. Importantly, a search aggregator layer seamlessly combines text searches from the Elasticsearch engine with specialized bioinformatics algorithms that perform searches against macromolecular sequence and/or atomic coordinate data. Examples of the searches integrated by the aggregator are mmseqs2 sequence search (1), BioZernike structure shape search (2), and sequence motif search. Users of existing services are strongly encouraged to migrate to the new
doi:10.1107/s0108767320099298 fatcat:yvixhxqrt5aofi45w4iuldmyty

Rap1GAP Mediates Angiotensin II-Induced Cardiomyocyte Hypertrophy by Inhibiting Autophagy and Increasing Oxidative Stress

Yan Gao, Di Zhao, Wen-zhi Xie, Tingting Meng, Chunxiao Xu, Yutong Liu, Pengfei Zhang, Xiuping Bi, Zhuo Zhao, Rodrigo Franco
2021 Oxidative Medicine and Cellular Longevity  
Abnormal autophagy and oxidative stress contribute to angiotensin II- (Ang II-) induced cardiac hypertrophy and heart failure. We previously showed that Ang II increased Rap1GAP gene expression in cardiomyocytes associated with hypertrophy and autophagy disorders. Using real-time PCR and Western blot, we found that Rap1GAP expression was increased in the heart of Sprague Dawley (SD) rats infused by Ang II compared with saline infusion and in Ang II vs. vehicle-treated rat neonatal
more » ... . Overexpression of Rap1GAP in cultured cardiomyocytes exacerbated Ang II-induced cardiomyocyte hypertrophy, reactive oxygen species (ROS) generation, and cell apoptosis and inhibited autophagy. The increased oxidative stress caused by Rap1GAP overexpression was inhibited by the treatment of autophagy agonists. Knockdown of Rap1GAP by siRNA markedly attenuated Ang II-induced cardiomyocyte hypertrophy and oxidative stress and enhanced autophagy. The AMPK/AKT/mTOR signaling pathway was inhibited by overexpression of Rap1GAP and activated by the knockdown of Rap1GAP. These results show that Rap1GAP-mediated pathway might be a new mechanism of Ang II-induced cardiomyocyte hypertrophy, which could be a potential target for the future treatment of cardiac hypertrophy and heart failure.
doi:10.1155/2021/7848027 pmid:33936386 pmcid:PMC8062190 fatcat:yciwaig6vjah7c2jm3offod3hm

A UFLC/MS/MS method for simultaneous quantitation of alisol A and alisol B 23-acetate from Alisma orientale (Sam.) Juz. in rat plasma

Yaowen Zhang, Qing Li, Chunxiao Lv, Yidi Yin, Kaishun Bi
2014 Asian Journal of Pharmaceutical Sciences  
Alisol A Alisol B 23-acetate UFLC-MS/MS Alisma orientale (Sam.) Juz a b s t r a c t A sensitive and reliable ultra fast liquid chromatography tandem mass spectrometry (UFLC-MS/MS) method has been developed and validated for simultaneous quantitation of alisol A and alisol B 23-acetate from Alisma orientale (Sam.) Juz. in rat plasma using diazepam as an internal standard (IS). The plasma samples were extracted by liquideliquid extraction with methyl tert-butyl ether and separated on a Venusil MP
more » ... C18 column (100 mm 2.1 mm, 3.0 mm) (Venusil, China) using gradient elution with the mobile phase consisting of methanol and 0.1% acetic acid in water at a flow rate of 0.4 ml/min. The two analytes were monitored with positive electrospray ionization by multiple reaction monitoring mode (MRM). The lower limit of quantitation was 5.00 ng/ml for alisol A and 5.00 ng/ml for alisol B 23-acetate. The calibration curves were linear in the range of 5.00 e2500 ng/ml for alisol A and 5e2500 ng/ml for alisol B 23-acetate. The mean extraction recoveries were above 63.8% for alisol A and 68.0% for alisol B 23-acetate from biological matrixes. Both intra-day and inter-day precision and accuracy of analytes were well within acceptance criteria (15%). The validated method was successfully applied to the pharmacokinetic study of alisol A and alisol B 23-acetate in rat plasma after oral administration of alcohol extract of Alismatis Rhizoma.
doi:10.1016/j.ajps.2014.08.001 fatcat:56hpscqlnrayrjg4zx7xh6uxme

Associations of C-reactive Protein with 25-hydroxyvitamin D in 24 Specific Diseases: A Cross-sectional Study from NHANES

Fang Yang, Mengzi Sun, Chong Sun, Jiagen Li, Xiuning Yang, Chunli Bi, Min Wang, Liyuan Pu, Jianmeng Wang, Chunxiao Wang, Meizhen Xie, Yan Yao (+1 others)
2020 Scientific Reports  
Most diseases might be associated with acute or chronic inflammation, and the role of vitamin D in diseases has been extensively explored in recent years. Thus, we examined the associations of one of the best markers for inflammation - C-reactive protein (CRP) with 25-hydroxyvitamin D [25(OH)D] in 24 specific diseases. We performed cross-sectional analyses among 9,809 subjects aged ≥18 years who participated in the U.S. National Health and Nutrition Examination Survey (NHANES) in 2007~2010. The
more » ... generalized additive model (GAM) was used to explore the associations of CRP with 25(OH)D in different diseases, adjusted for the age, gender, examination period and race. Distributions of CRP were significantly different (P < 0.05) in gender, examination period and race, and distributions of 25(OH)D were different (P < 0.05) in the examination period and race. Generally, CRP was negatively associated with 25(OH)D for majority diseases. 25(OH)D was negatively associated with CRP generally, and the associations were disease-specific and disease category-specific. In respiratory, gastrointestinal and mental diseases, the associations tended to be approximately linear. While in metabolic diseases, the associations were nonlinear, and the slope of the nonlinear curve decreased with 25(OH)D, especially when 25(OH)D < 30 μg/L.
doi:10.1038/s41598-020-62754-w pmid:32246038 fatcat:j4g4fdc7xbgr5ddw44ptocgvuq

Glucocorticoid receptor promotes the function of myeloid-derived suppressor cells by suppressing HIF1α-dependent glycolysis

Yun Lu, Huanrong Liu, Yujing Bi, Hui Yang, Yan Li, Jian Wang, Zhengguo Zhang, Yu Wang, Chunxiao Li, Anna Jia, Linian Han, Ying Hu (+3 others)
2017 Cellular & Molecular Immunology  
Immunomodulatory signaling imposes tight regulations on metabolic programs within immune cells and consequentially determines immune response outcomes. Although the glucocorticoid receptor (GR) has been recently implicated in regulating the function of myeloid-derived suppressor cells (MDSCs), whether the dysregulation of GR in MDSCs is involved in immune-mediated hepatic diseases and how GR regulates the function of MDSCs in such a context remains unknown. Here, we revealed the dysregulation
more » ... GR expression in MDSCs during innate immunological hepatic injury (IMH) and found that GR regulates the function of MDSCs through modulating HIF1α-dependent glycolysis. Pharmacological modulation of GR by its agonist (dexamethasone, Dex) protects IMH mice against inflammatory injury. Mechanistically, GR signaling suppresses HIF1α and HIF1αdependent glycolysis in MDSCs and thus promotes the immune suppressive activity of MDSCs. Our studies reveal a role of GR-HIF1α in regulating the metabolism and function of MDSCs and further implicate MDSC GR signaling as a potential therapeutic target in hepatic diseases that are driven by innate immune cell-mediated systemic inflammation.
doi:10.1038/cmi.2017.5 pmid:28287112 pmcid:PMC6079089 fatcat:exlig6kmurda7lgnururmppnmu

The RCSB Protein Data Bank: new resources for research and education

Peter W. Rose, Chunxiao Bi, Wolfgang F. Bluhm, Cole H. Christie, Dimitris Dimitropoulos, Shuchismita Dutta, Rachel K. Green, David S. Goodsell, Andreas Prlić, Martha Quesada, Gregory B. Quinn, Alexander G. Ramos (+5 others)
2012 Nucleic Acids Research  
The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB) develops tools and resources that provide a structural view of biology for research and education. The RCSB PDB web site (http://www.rcsb.org) uses the curated 3D macromolecular data contained in the PDB archive to offer unique methods to access, report and visualize data. Recent activities have focused on improving methods for simple and complex searches of PDB data, creating specialized access to chemical
more » ... ponent data and providing domain-based structural alignments. New educational resources are offered at the PDB-101 educational view of the main web site such as Author Profiles that display a researcher's PDB entries in a timeline. To promote different kinds of access to the RCSB PDB, Web Services have been expanded, and an RCSB PDB Mobile application for the iPhone/iPad has been released. These improvements enable new opportunities for analyzing and understanding structure data.
doi:10.1093/nar/gks1200 pmid:23193259 pmcid:PMC3531086 fatcat:jx4ewohcyrayre6yw4zmlqu74q
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