322 results on '"Xin Chen"'
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2. Cost-effectiveness and cost-utility analyses of three different gargles in the treatment of chronic periodontitis.
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Xin Chen, Wenzhi Niu, Guangyu Hu, and Changfeng Chen
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Medicine ,Science - Abstract
ObjectiveThis study aimed to investigate the economics of three different gargles in the treatment of chronic periodontitis.MethodsA total of 108 patients with periodontitis received one of the following three gargles: xipayi, compound chlorhexidine, or Kangfuxin gargle. The basic information of the patients, the costs of the gargles, the periodontal indexes before and after treatment, and the scores of the 3-level version of the EuroQol Five Dimensions Questionnaire were collected. The cost-effectiveness and cost-utility of the various gargles were determined.ResultsThe cost-effectiveness ratios (CER) of the three groups after treatment were 1828.75, 1573.34, and 1876.92 RMB, respectively. The utility values before treatment were 0.92, 0.90, and 0.91, respectively, and the utility values after treatment were 0.98, 0.98, and 0.97, respectively. The cost-utility ratios (CURs) were 213.43, 195.61, and 301.53 RMB, respectively.ConclusionsFor each increase in effective rate and quality-adjusted life years, the treatment cost of periodontitis patients was lower than the gross domestic product per capita of Jiangsu Province, indicating that the treatment cost is completely worth it. The CER and CUR results were the same, and the compound chlorhexidine group was the lowest, demonstrating that when the same therapeutic effect was achieved, it cost the least.
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- 2024
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3. Assessing the causal associations of different types of statins use and knee/hip osteoarthritis: A Mendelian randomization study.
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Xin Chen, Xin Huang, Youqun Liu, Zhiwei Zhang, and Jiliang Chen
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Medicine ,Science - Abstract
ObjectiveThis study comprehensively evaluated the causal relationship between different types of statins use and knee/hip osteoarthritis (OA) using a two-sample and multivariate Mendelian randomization (MR) method.MethodsMR analysis was conducted using publicly available summary statistics data from genome-wide association studies (GWAS) to assess the causal associations between total statins use (including specific types) and knee/hip OA. The primary analysis utilized the inverse variance-weighted (IVW) method, with sensitivity analysis conducted to assess robustness. Multivariable MR (MVMR) analysis adjusted for low-density lipoprotein cholesterol (LDL-C), intermediate-density lipoprotein cholesterol (IDL-C), high-density lipoprotein cholesterol (HDL-C), and body mass index (BMI).ResultsThe MR analysis revealed a significant inverse association between genetically predicted total statins use and the risk of knee OA (OR = 0.950, 95%CI: 0.920-0.982, p = 0.002) as well as hip OA (OR = 0.932, 95%CI: 0.899-0.966, p ConclusionThis study provides compelling evidence of the close relationship between statin use and a reduced risk of knee/hip OA, particularly with atorvastatin and simvastatin. LDL-C and IDL-C may mediate these effects. These findings have important implications for the clinical prevention and treatment of knee/hip OA.
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- 2024
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4. The impacts of economic policy uncertainty on firm cash holding in China.
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Xin Chen, Jiannan Li, Decai Tang, Li Shang, Valentina Boamah, Jiayi Xu, and Zixuan Deng
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Medicine ,Science - Abstract
Cash holding is an important strategic decision of enterprises. As a macro-level factor, economic policy uncertainty causes risks, affecting enterprises' cash holdings. Taking the quarterly financial data of China's A-share non-financial listed firms for 2010-2020 as a sample, this study adopts the OLS and fixed effect models to investigate how corporate cash holdings are affected by economic policy uncertainty. The findings indicate that economic policy uncertainty is directly proportional to the level of cash that listed corporations hold. The higher the uncertainty, the more cash the company holds. Among them, state-owned enterprises and the manufacturing industry are more significantly affected by economic policy uncertainty. Finally, considering the regional marketization level and the differences in financing constraints enterprises face, it is concluded through grouping empirical studies that enterprises located in regions with lower marketization levels are more susceptible to policy uncertainty, while financially constrained enterprises are more susceptible to economic policy uncertainty. The study of economic policy uncertainty is helpful to guide enterprises to realize the importance of coping strategies in advance under the background of intensifying economic policy uncertainty. Therefore, this paper proposes to introduce policies on the premise of fully considering the smoothness of the economy and the differences in the conditions of firms of different natures, as well as some proposals to alleviate financing constraints, reduce the adverse effects of uncertainty on firms, and bolster the marketization process.
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- 2023
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5. Evaluation of the operation status of the residential land market in Beijing-Tianjin-Hebei region of China and its spatiotemporal pattern characteristics.
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Xin Chen, Can Li, Huixia Li, Jingfeng Ge, Wengang Wang, and Pengfei An
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Medicine ,Science - Abstract
Exploring the operation status and patterns of urban land markets is an important theoretical and practical topic for promoting coordinated socio-economic development. In this study, the operation status of the residential land market in the Beijing-Tianjin-Hebei region and the characteristics of its pattern were analyzed using the composite index method and the 3σ rule of the normal distribution and taking the 174 counties in Beijing, Tianjin, and Hebei, China, as the research objects. The results show that ① Beijing, Tianjin, Langfang, Zhangjiakou, and Baoding residential land market state composite indexes are all in the middle to upper levels in the Beijing-Tianjin-Hebei city cluster, while Qinhuangdao, Handan, and Chengde residential land market state composite indexes are generally low. The harmony between the residential land price and national economy, the market supply and demand balance, and the structural balance may become the main factors affecting the healthy development of the residential land market in Beijing and Tianjin. ② The proportion of counties with "healthy" residential land market in all dimensions and overall market status reached over 64%, and the residential land market in the Beijing-Tianjin-Hebei region is running well. The rapid increase in residential land prices from 2016 to 2020 was an important driver of the increased heat in the residential land market across the region. ③ The residential land market in the counties around Beijing and Tianjin is significantly hotter than in other regions, and there is an obvious polarization effect in the operation state of the residential land market in the Beijing-Tianjin region. The residential land market is generally cold in the counties in the southern and northeastern parts of the region and other peripheral areas, and there is a risk of marginalization in the development of the residential land market in the counties in the peripheral areas. ④ Both the hot and cold residential land market states exhibit spatial clustering characteristics. Most of the clusters are not consistent with the municipal administrative boundaries, and the states of the residential land market in neighboring counties are very similar.
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- 2023
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6. Variation in carbon and nitrogen concentrations among peatland categories at the global scale.
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Shaun Watmough, Spencer Gilbert-Parkes, Nathan Basiliko, Louis J Lamit, Erik A Lilleskov, Roxanne Andersen, Jhon Del Aguila-Pasquel, Rebekka E Artz, Brian W Benscoter, Werner Borken, Luca Bragazza, Stefani M Brandt, Suzanna L Bräuer, Michael A Carson, Xin Chen, Rodney A Chimner, Bev R Clarkson, Alexander R Cobb, Andrea S Enriquez, Jenny Farmer, Samantha P Grover, Charles F Harvey, Lorna I Harris, Christina Hazard, Alison M Hoyt, John Hribljan, Jyrki Jauhiainen, Sari Juutinen, Evan S Kane, Klaus-Holger Knorr, Randy Kolka, Mari Könönen, Anna M Laine, Tuula Larmola, Patrick A Levasseur, Carmody K McCalley, Jim McLaughlin, Tim R Moore, Nadia Mykytczuk, Anna E Normand, Virginia Rich, Bryce Robinson, Danielle L Rupp, Jasmine Rutherford, Christopher W Schadt, Dave S Smith, Graeme Spiers, Leho Tedersoo, Pham Q Thu, Carl C Trettin, Eeva-Stiina Tuittila, Merritt Turetsky, Zuzana Urbanová, Ruth K Varner, Mark P Waldrop, Meng Wang, Zheng Wang, Matt Warren, Magdalena M Wiedermann, Shanay T Williams, Joseph B Yavitt, Zhi-Guo Yu, and Geoff Zahn
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Medicine ,Science - Abstract
Peatlands account for 15 to 30% of the world's soil carbon (C) stock and are important controls over global nitrogen (N) cycles. However, C and N concentrations are known to vary among peatlands contributing to the uncertainty of global C inventories, but there are few global studies that relate peatland classification to peat chemistry. We analyzed 436 peat cores sampled in 24 countries across six continents and measured C, N, and organic matter (OM) content at three depths down to 70 cm. Sites were distinguished between northern (387) and tropical (49) peatlands and assigned to one of six distinct broadly recognized peatland categories that vary primarily along a pH gradient. Peat C and N concentrations, OM content, and C:N ratios differed significantly among peatland categories, but few differences in chemistry with depth were found within each category. Across all peatlands C and N concentrations in the 10-20 cm layer, were 440 ± 85.1 g kg-1 and 13.9 ± 7.4 g kg-1, with an average C:N ratio of 30.1 ± 20.8. Among peatland categories, median C concentrations were highest in bogs, poor fens and tropical swamps (446-532 g kg-1) and lowest in intermediate and extremely rich fens (375-414 g kg-1). The C:OM ratio in peat was similar across most peatland categories, except in deeper samples from ombrotrophic tropical peat swamps that were higher than other peatlands categories. Peat N concentrations and C:N ratios varied approximately two-fold among peatland categories and N concentrations tended to be higher (and C:N lower) in intermediate fens compared with other peatland types. This study reports on a unique data set and demonstrates that differences in peat C and OM concentrations among broadly classified peatland categories are predictable, which can aid future studies that use land cover assessments to refine global peatland C and N stocks.
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- 2022
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7. Decreased accuracy of erythrocyte sedimentation rate in diagnosing osteomyelitis in diabetic foot infection patients with severe renal impairment: A retrospective cross-sectional study
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Xin Chen, Yiting Shen, Yuying Wang, Yang Li, Shuyu Guo, Yue Liang, Xuanyu Wang, Siyuan Zhou, Xiaojie Hu, Kaiwen Ma, Rui Tian, Wenting Fei, Yuqin Sheng, Hengjie Cao, and Huafa Que
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Medicine ,Science - Abstract
Background Rapid diagnosis and treatment of diabetic foot osteomyelitis (DFO) could reduce the risk of amputation and death in patients with diabetic foot infection (DFI). Erythrocyte sedimentation rate (ESR) is considered the most useful serum inflammatory marker for the diagnosis of DFO. However, whether severe renal impairment (SRI) affects its diagnostic accuracy has not been reported previously. Objective To investigate the accuracy of ESR in diagnosing DFO in DFI patients with and without SRI. Methods This was a retrospective cross-sectional study. From the inpatient electronic medical record system, the investigators extracted demographic information, diagnostic information, and laboratory test results of patients with DFI who had been hospitalized in Longhua Hospital from January 1, 2016 to September 30, 2021. Logistic regression was performed to analyze the interaction between ESR and SRI with adjustment for potential confounders. The area under the curve (AUC), cutoff point, sensitivity, specificity, prevalence, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), and negative likelihood ratio (LR−) were analyzed by receiver operating characteristic (ROC) curve analysis and VassarStats. Results A total of 364 DFI patients were included in the analysis. The logistic regression analysis results showed that elevated ESR increased the probability of diagnosing DFO (adjusted odds ratio [OR], 2.40; 95% confidence interval [CI], 1.75–3.28; adjusted P < 0.001); SRI was not associated with the diagnosis of DFO (adjusted OR, 3.20; 95% CI, 0.40–25.32; adjusted P = 0.271), but it had an obstructive effect on the diagnosis of DFO by ESR (adjusted OR, 0.48; 95% CI, 0.23–0.99; adjusted P = 0.048). ROC analysis in DFI patients without SRI revealed that the AUC of ESR to diagnose DFO was 0.76 (95% CI, 0.71–0.81), with the cutoff value of 45 mm/h (sensitivity, 67.8%; specificity, 78.0%; prevalence, 44.7%; PPV, 71.3%; NPV, 75.0%; LR+, 3.08; LR−, 0.41). In contrast, in patients with SRI, the AUC of ESR to diagnose DFO was 0.57 (95% CI, 0.40–0.75), with the cutoff value of 42 mm/h (sensitivity, 95.0%; specificity, 29.2%; prevalence, 45.5%; PPV, 52.8%; NPV, 87.5%; LR+, 1.34; LR−, 0.17). Conclusions The accuracy of ESR in diagnosing DFO in DFI patients with SRI is reduced, and it may not have clinical diagnostic value in these patients.
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- 2022
8. Predicted mouse interactome and network-based interpretation of differentially expressed genes.
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Hai-Bo Zhang, Xiao-Bao Ding, Jie Jin, Wen-Ping Guo, Qiao-Lei Yang, Peng-Cheng Chen, Heng Yao, Li Ruan, Yu-Tian Tao, and Xin Chen
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Medicine ,Science - Abstract
The house mouse or Mus musculus has become a premier mammalian model for genetic research due to its genetic and physiological similarities to humans. It brought mechanistic insights into numerous human diseases and has been routinely used to assess drug efficiency and toxicity, as well as to predict patient responses. To facilitate molecular mechanism studies in mouse, we present the Mouse Interactome Database (MID, Version 1), which includes 155,887 putative functional associations between mouse protein-coding genes inferred from functional association evidence integrated from 9 public databases. These putative functional associations are expected to cover 19.32% of all mouse protein interactions, and 26.02% of these function associations may represent protein interactions. On top of MID, we developed a gene set linkage analysis (GSLA) web tool to annotate potential functional impacts from observed differentially expressed genes. Two case studies show that the MID/GSLA system provided precise and informative annotations that other widely used gene set annotation tools, such as PANTHER and DAVID, did not. Both MID and GSLA are accessible through the website http://mouse.biomedtzc.cn.
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- 2022
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9. Risk factors for surgical site infection in patients undergoing colorectal surgery: A meta-analysis of observational studies
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ZhaoHui Xu, Hui Qu, ZeZhong Gong, George Kanani, Fan Zhang, YanYing Ren, Shuai Shao, XiaoLiang Chen, and Xin Chen
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Medicine ,Science - Abstract
Objective Surgical site infection (SSI) is the second most prevalent hospital-based infection and affects the surgical therapeutic outcomes. However, the factors of SSI are not uniform. The main purpose of this study was to understand the risk factors for the different types of SSI in patients undergoing colorectal surgery (CRS). Methods PubMed, EMBASE, and Cochrane Library databases were searched using the relevant search terms. The data extraction was independently performed by two investigators using a standardized format, following the pre-agreed criteria. Meta-analysis for the risk factors of SSI in CRS patients was carried out using Review Manager 5.3 (RevMan 5.3) and Stata 15.1 software. The quality of evidence was evaluated using total sample size, Egger’s P-value, and intergroup heterogeneity, which contained three levels: high-quality (Class I), moderate-quality (Class II/III), and low-quality (Class IV). The publication bias of the included studies was assessed using funnel plots, Begg’s test, and Egger’s test. Results Of the 2660 potentially eligible studies, a total of 31 studies (22 retrospective and 9 prospective cohort studies) were included in the final analysis. Eventually, the high-quality evidence confirmed that SSI was correlated with obesity (RR = 1.60, 95% confidence interval (CI): 1.47–1.74), ASA score ≥3 (RR = 1.34, 95% CI: 1.19–1.51), and emergent surgery (RR = 1.36, 95% CI: 1.19–1.55). The moderate-quality evidence showed the correlation of SSI with male sex (RR = 1.30, 95% CI: 1.14–1.49), diabetes mellitus (RR = 1.65, 95% CI: 1.24–2.20), inflammatory bowel disease (RR = 2.12, 95% CI: 1.24–3.61), wound classification >2 (RR = 2.65, 95% CI: 1.52–4.61), surgery duration ≥180 min (RR = 1.88, 95% CI: 1.49–2.36), cigarette smoking (RR = 1.38, 95% CI: 1.14–1.67), open surgery (RR = 1.81, 95% CI: 1.57–2.10), stoma formation (RR = 1.89, 95% CI: 1.28–2.78), and blood transfusion (RR = 2.03, 95% CI:1.34–3.06). Moderate-quality evidence suggested no association with respiratory comorbidity (RR = 2.62, 95% CI:0.84–8.13) and neoplasm (RR = 1.24, 95% CI:0.58–2.26). Meanwhile, the moderate-quality evidence showed that the obesity (RR = 1.28, 95% CI: 1.24–1.32) and blood transfusion (RR = 2.32, 95% CI: 1.26–4.29) were independent risk factors for organ/space SSI (OS-SSI). The high-quality evidence showed that no correlation of OS-SSI with ASA score ≥3 and stoma formation. Furthermore, the moderate-quality evidence showed that no association of OS-SSI with open surgery (RR = 1.37, 95% CI: 0.62–3.04). The high-quality evidence demonstrated that I-SSI was correlated with stoma formation (RR = 2.55, 95% CI: 1.87–3.47). There were some certain publication bias in 2 parameters based on asymmetric graphs, including diabetes mellitus and wound classification >2. The situation was corrected using the trim and fill method. Conclusions The understanding of these factors might make it possible to detect and treat the different types of SSI more effectively in the earlier phase and might even improve the patient’s clinical prognosis. Evidence should be continuously followed up and updated, eliminating the potential publication bias. In the future, additional high-level evidence is required to verify these findings.
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- 2021
10. Quality of life and outcomes in heart failure patients with ejection fractions in different ranges.
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Xin Chen, Yanguo Xin, Wenyu Hu, Yinan Zhao, Zixin Zhang, and Yinpin Zhou
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Medicine ,Science - Abstract
AIMS:Guidelines divide patients with heart failure (HF) into 3 distinct groups based on left ventricular ejection fraction (LVEF) We used the Minnesota Living with Heart Failure Questionnaire (MLHFQ) to quantify the health-related quality of life in patients with HF. METHODS:Patients were stratified into three cohorts: preserved LVEF (>50%), mid-range LVEF (40-49%) and reduced LVEF (
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- 2019
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11. Traditional and systems biology based drug discovery for the rare tumor syndrome neurofibromatosis type 2.
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Synodos for NF2 Consortium, Robert Allaway, Steve P Angus, Roberta L Beauchamp, Jaishri O Blakeley, Marga Bott, Sarah S Burns, Annemarie Carlstedt, Long-Sheng Chang, Xin Chen, D Wade Clapp, Patrick A Desouza, Serkan Erdin, Cristina Fernandez-Valle, Justin Guinney, James F Gusella, Stephen J Haggarty, Gary L Johnson, Salvatore La Rosa, Helen Morrison, Alejandra M Petrilli, Scott R Plotkin, Abhishek Pratap, Vijaya Ramesh, Noah Sciaky, Anat Stemmer-Rachamimov, Tim J Stuhlmiller, Michael E Talkowski, D Bradley Welling, Charles W Yates, Jon S Zawistowski, and Wen-Ning Zhao
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Medicine ,Science - Abstract
Neurofibromatosis 2 (NF2) is a rare tumor suppressor syndrome that manifests with multiple schwannomas and meningiomas. There are no effective drug therapies for these benign tumors and conventional therapies have limited efficacy. Various model systems have been created and several drug targets have been implicated in NF2-driven tumorigenesis based on known effects of the absence of merlin, the product of the NF2 gene. We tested priority compounds based on known biology with traditional dose-concentration studies in meningioma and schwann cell systems. Concurrently, we studied functional kinome and gene expression in these cells pre- and post-treatment to determine merlin deficient molecular phenotypes. Cell viability results showed that three agents (GSK2126458, Panobinostat, CUDC-907) had the greatest activity across schwannoma and meningioma cell systems, but merlin status did not significantly influence response. In vivo, drug effect was tumor specific with meningioma, but not schwannoma, showing response to GSK2126458 and Panobinostat. In culture, changes in both the transcriptome and kinome in response to treatment clustered predominantly based on tumor type. However, there were differences in both gene expression and functional kinome at baseline between meningioma and schwannoma cell systems that may form the basis for future selective therapies. This work has created an openly accessible resource (www.synapse.org/SynodosNF2) of fully characterized isogenic schwannoma and meningioma cell systems as well as a rich data source of kinome and transcriptome data from these assay systems before and after treatment that enables single and combination drug discovery based on molecular phenotype.
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- 2018
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12. Real-world PD-L1 testing and distribution of PD-L1 tumor expression by immunohistochemistry assay type among patients with metastatic non-small cell lung cancer in the United States.
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Vamsidhar Velcheti, Pallavi D Patwardhan, Frank Xiaoqing Liu, Xin Chen, Xiting Cao, and Thomas Burke
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Medicine ,Science - Abstract
BACKGROUND:The anti-programmed death receptor-1 (anti-PD-1) pembrolizumab is approved as first-line monotherapy for metastatic non-small cell lung cancer (mNSCLC) with PD-ligand 1 (PD-L1) tumor expression ≥50%. Most studies comparing PD-L1 results by immunohistochemistry (IHC) assay type have been conducted by prespecified and, in most cases, highly experienced, trained pathologists; however, knowledge is limited regarding the current use and concordance of PD-L1 assays in the real-world clinical setting. Our aim was to study the distribution of PD-L1 tumor expression by IHC assay type among patients with mNSCLC in US oncology practices. METHODS:This retrospective observational study utilized de-identified, longitudinal data from a large US electronic medical record database. Eligible patients were adults (≥18 years) with histologically/cytologically confirmed initial diagnosis of metastatic or recurrent NSCLC from October 2015 through December 2017. We determined PD-L1 testing trends and distribution of PD-L1 tumor expression (percentage of tumor cells staining for PD-L1) by IHC assay type. RESULTS:The 12,574 eligible patients (mean age, 69 years) included 6,620 (53%) men and 86% with positive smoking history. Of 4,868 evaluable tests, 3,799 (78%), 195 (4%), 165 (3%), and 709 (15%) used the Agilent 22C3 pharmDx, Agilent 28-8 pharmDx, Ventana PD-L1 (SP142) Assay, and laboratory-developed tests (LDTs, including SP263), respectively. The percentages of tests scoring PD-L1 tumor expression of ≥50% were 33%, 32%, 10%, and 23%, respectively. Measured PD-L1 tumor expression varied across the four assay types (χ2 p < 0.001) and across three assay types excluding SP142 (p < 0.001), with no significant difference between 22C3 and 28-8 assays (p = 0.96). The PD-L1 testing rate increased from 18% in the fourth quarter of 2015 to 71% in the fourth quarter of 2017. CONCLUSIONS:In the real-world clinical setting, we observed that measured PD-L1 tumor expression is concordant using the 22C3 and 28-8 assays; however, the SP142 assay and LDTs appear discordant and could underestimate high PD-L1 positivity. Further study is needed to evaluate the association between PD-L1 tumor expression and response to therapy.
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- 2018
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13. Growth differentiation factor-15 levels and the risk of contrast induced nephropathy in patients with acute myocardial infarction undergoing percutaneous coronary intervention: A retrospective observation study.
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Ling Sun, Xuejun Zhou, Jianguang Jiang, Xuan Zang, Xin Chen, Haiyan Li, Haitao Cao, and Qingjie Wang
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Medicine ,Science - Abstract
AIMS:To investigate the association between growth differentiation factor-15 (GDF-15) and contrast-induced nephropathy (CIN) in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI). METHODS:A total of 311 patients with AMI were studied retrospectively. All patients were divided into two groups according to the occurrence of CIN after PCI. Baseline clinical data were compared between two groups. Multivariate logistic regression analysis was used to identify the risk factors for CIN. Cox regression analysis was used to identify the association between GDF-15, CIN and short-term outcome. RESULTS:There were 80 patients in CIN group (average age was 71.60 ± 13.00 years; 67.5% male) and 231 patients in non-CIN group (average age was 63.80 ± 11.70 years; 71.9%male). The concentration of GDF-15 in CIN group was higher than that of non-CIN group (1232 ± 366.6 ng/L vs. 939.20 ± 309.6 ng/L, P
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- 2018
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14. GATA4 inhibits cell differentiation and proliferation in pancreatic cancer.
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Yan Gong, Liang Zhang, Aiqun Zhang, Xin Chen, Peng Gao, and Qiang Zeng
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Medicine ,Science - Abstract
Pancreatic ductal carcinoma (PDAC) is a common malignant tumor of the digestive system. GATA4 is one of the transcriptional regulatory factors, which regulates the development of endoderm-derived organs, including heart and gut. GATA4 may act as a putative tumor suppressor gene. However, the role of GATA4 in pancreatic carcinogenesis is not yet clarified. This study showed that GATA4 was highly expressed in pancreatic cancer tissues, and its expression level was positively related to the grade of pathological differentiation, suggesting that it may contribute to the progression of pancreatic neoplasia. Ectopic expression of GATA4 gene reduced cell viability and interference of GATA4 expression significantly increased the colony formation ability of pancreatic cancer cells. Furthermore, GATA4 inhibited tumor growth in xenograft mice. Agilent expression microarray profiling analysis indicated that the genes with significant levels of differential expression in GATA4 over-expressing cells were enriched in the cell differentiation process. Analysis of KEGG signaling pathway demonstrated that the regulated genes were partially enriched in MAPK and JAK-STAT signaling pathways. Re-expression of GATA4 up-regulated P53 gene expression. Our data indicate that GATA4 gene might play a role in cell proliferation and differentiation during the progression of pancreatic cancer.
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- 2018
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15. Growth differentiation factor-15 levels and the risk of contrast induced acute kidney injury in acute myocardial infarction patients treated invasively: A propensity-score match analysis.
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Ling Sun, Xuejun Zhou, Jianguang Jiang, Xuan Zang, Xin Chen, Haiyan Li, Haitao Cao, and Qingjie Wang
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Medicine ,Science - Abstract
Growth differentiation factor-15 (GDF-15) is an emerging biomarker for risk stratification in cardiovascular disease. Contrast-induced acute kidney injury (AKI) is an important complication in patients undergoing coronary angiography (CAG) or percutaneous coronary intervention (PCI). In this retrospectively observational study, we aimed to determine the role of GDF-15 and the risk of AKI in acute myocardial infarction (AMI) patients.The medical records of 1195 patients with AMI were reviewed. After exclusion criteria, a total of 751 eligible patients who underwent CAG or PCI were studied. Preoperative clinical parameters including GDF-15 levels were recorded. Multivariate logistic regression analysis was used to identify the risk factors of AKI. Subsequently, to reduce a potential selection bias and to balance differences between the two groups, a propensity score-matched analysis was performed. We recorded the 30-day all-cause mortality of the total study population. Kaplan-Meier analysis was performed to identify the association between short term survival in AMI patients and GDF-15 level.Among 751 enrolled patients, 106 patients (14.1%) developed AKI. Patients were divided into two groups: AKI group (n = 106) and non-AKI group (n = 645). GDF-15 levels were significantly higher in AKI group compared to non-AKI group (1328.2 ± 349.7 ng/L vs. 1113.0 ± 371.3 ng/L, P
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- 2018
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16. Tankyrase inhibitors suppress hepatocellular carcinoma cell growth via modulating the Hippo cascade.
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Jiaoyuan Jia, Yu Qiao, Maria G Pilo, Antonio Cigliano, Xianqiong Liu, Zixuan Shao, Diego F Calvisi, and Xin Chen
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Medicine ,Science - Abstract
Previous data indicate that Tankyrase inhibitors exert anti-growth functions in many cancer cell lines due to their ability to inactivate the YAP protooncogene. In the present manuscript, we investigated the effect of Tankyrase inhibitors on the growth of hepatocellular carcinoma (HCC) cell lines and the molecular mechanisms involved. For this purpose, we performed cell proliferation assay by colony-forming ability in seven human HCC cells subjected to XAV-939 and G007-LK Tankyrase inhibitors. Noticeably, the two Tankyrase inhibitors suppressed the HCC cell growth in a dose-dependent manner. Furthermore, we found that Tankyrase inhibitors synergized with MEK and AKT inhibitors to suppress HCC cell proliferation. At the molecular level, Tankyrase inhibitors significantly decreased YAP protein levels, reduced the expression of YAP target genes, and inhibited YAP/TEAD luciferase reporter activity. In addition, Tankyrase inhibitors administration was accompanied by upregulation of Angiomotin-like 1 (AMOTL1) and Angiomotin-like 2 (AMOTL2) proteins, two major negative regulators of YAP. Altogether, the present data indicate that XAV-939 and G007-LK Tankyrase inhibitors could suppress proliferation of hepatocellular carcinoma cells and downregulate YAP/TAZ by stabilizing AMOTL1 and AMOTL2 proteins, thus representing new potential anticancer drugs against hepatocellular carcinoma.
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- 2017
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17. Transcriptome analysis of hexaploid hulless oat in response to salinity stress.
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Bin Wu, Yani Hu, Pengjie Huo, Qian Zhang, Xin Chen, and Zongwen Zhang
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Medicine ,Science - Abstract
BACKGROUND:Oat is a cereal crop of global importance used for food, feed, and forage. Understanding salinity stress tolerance mechanisms in plants is an important step towards generating crop varieties that can cope with environmental stresses. To date, little is known about the salt tolerance of oat at the molecular level. To better understand the molecular mechanisms underlying salt tolerance in oat, we investigated the transcriptomes of control and salt-treated oat using RNA-Seq. RESULTS:Using Illumina HiSeq 4000 platform, we generated 72,291,032 and 356,891,432 reads from non-stressed control and salt-stressed oat, respectively. Assembly of 64 Gb raw sequence data yielded 128,414 putative unique transcripts with an average length of 1,189 bp. Analysis of the assembled unigenes from the salt stressed and control libraries indicated that about 65,000 unigenes were differentially expressed at different stages. Functional annotation showed that ABC transporters, plant hormone signal transduction, plant-pathogen interactions, starch and sucrose metabolism, arginine and proline metabolism, and other secondary metabolite pathways were enriched under salt stress. Based on the RPKM values of assembled unigenes, 24 differentially expressed genes under salt stress were selected for quantitative RT-PCR validation, which successfully confirmed the results of RNA-Seq. Furthermore, we identified 18,039 simple sequence repeats, which may help further elucidate salt tolerance mechanisms in oat. CONCLUSIONS:Our global survey of transcriptome profiles of oat plants in response to salt stress provides useful insights into the molecular mechanisms underlying salt tolerance in this crop. These findings also represent a rich resource for further analysis of salt tolerance and for breeding oat with improved salt tolerance through the use of salt-related genes.
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- 2017
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18. Backfilling behavior of a mixed aggregate based on construction waste and ultrafine tailings.
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Qiusong Chen, Qinli Zhang, Chongchun Xiao, and Xin Chen
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Medicine ,Science - Abstract
To study the possibility of utilizing mixed construction waste and ultrafine tailings (CW&UT) as a backfilling aggregate that can be placed underground in a mine, physicochemical evaluation, proportioning strength tests, and pumpability experiments were conducted. It was revealed that mixed CW&UT can be used as a backfilling aggregate due to the complementarities of their physicochemical properties. In addition, as the results of the proportioning strength tests show, the compressive strength of a cemented CW&UT backfilling specimen cured for 28 days, with a mass fraction of 72-74%, a cement-sand ratio of 1:12, and a CW proportion of 30%, is higher than 1.0 MPa, which meets the safety requirements and economic consideration of backfilling technology in many underground metal mines, and can also be enhanced with an increase in the cement-sand ratio. The results of the pumpability experiments show that cemented backfilling slurry based on CW&UT can be transported to the stope underground with a common filling pump, with a 16.6 MPa maximum pressure, with the condition that the time of emergency shut-down is less than approximately 20 min. All in all, the research to utilize mixed CW&UT as a backfilling aggregate can not only provide a way to dispose of CW&UT but also will bring large economic benefits and can provide constructive guidance for environmental protection.
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- 2017
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19. Instantaneous sediment transport model for asymmetric oscillatory sheet flow.
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Xin Chen, Yong Li, Genfa Chen, Fujun Wang, and Liuchao Qiu
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Medicine ,Science - Abstract
On the basis of advanced concentration and velocity profiles above a mobile seabed, an instantaneous analytical model is derived for sediment transport in asymmetric oscillatory flow. The applied concentration profile is obtained from the classical exponential law based on mass conservation, and asymmetric velocity profile is developed following the turbulent boundary layer theory and the asymmetric wave theory. The proposed model includes two parts: the basic part that consists of erosion depth and free stream velocity, and can be simplified to the total Shields parameter power 3/2 in accordance with the classical empirical models, and the extra vital part that consists of phase-lead, boundary layer thickness and erosion depth. The effects of suspended sediment, phase-lag and asymmetric boundary layer development are considered particularly in the model. The observed instantaneous transport rate proportional to different velocity exponents due to phase-lag is unified and summarised by the proposed model. Both instantaneous and half period empirical formulas are compared with the developed model, using extensive data on a wide range of flow and sediment conditions. The synchronous variation in instantaneous transport rate with free stream velocity and its decrement caused by increased sediment size are predicted correctly. Net transport rates, especially offshore transport rates with large phase-lag under velocity skewed flows, which existing instantaneous type formulas failed to predict, are predicted correctly in both direction and magnitude by the proposed model. Net sediment transport rates are affected not only by suspended sediment and phase-lag, but also by the boundary layer difference between onshore and offshore.
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- 2017
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20. The Arginine/Lysine-Rich Element within the DNA-Binding Domain Is Essential for Nuclear Localization and Function of the Intracellular Pathogen Resistance 1.
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Kezhen Yao, Yongyan Wu, Qi Chen, Zihan Zhang, Xin Chen, and Yong Zhang
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Medicine ,Science - Abstract
The mouse intracellular pathogen resistance 1 (Ipr1) gene plays important roles in mediating host immunity and previous work showed that it enhances macrophage apoptosis upon mycobacterium infection. However, to date, little is known about the regulation pattern of Ipr1 action. Recent studies have investigated the protein-coding genes and microRNAs regulated by Ipr1 in mouse macrophages, but the structure and the functional motif of the Ipr1 protein have yet to be explored. In this study, we analyzed the domains and functional motif of the Ipr1 protein. The resulting data reveal that Ipr1 protein forms a homodimer and that the Sp100-like domain mediates the targeting of Ipr1 protein to nuclear dots (NDs). Moreover, we found that an Ipr1 mutant lacking the classic nuclear localization signal (cNLS) also translocated into the nuclei, suggesting that the cNLS is not the only factor that directs Ipr1 nuclear localization. Additionally, mechanistic studies revealed that an arginine/lysine-rich element within the DNA-binding domain (SAND domain) is critical for Ipr1 binding to the importin protein receptor NPI-1, demonstrating that this element plays an essential role in mediating the nuclear localization of Ipr1 protein. Furthermore, our results show that this arginine/lysine-rich element contributes to the transcriptional regulation and apoptotic activity of Ipr1. These findings highlight the structural foundations of Ipr1 action and provide new insights into the mechanism of Ipr1-mediated resistance to mycobacterium.
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- 2016
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21. Effects of Genetically Modified Milk Containing Human Beta-Defensin-3 on Gastrointestinal Health of Mice.
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Xin Chen, Yange Yang, Zhaopeng Shi, Ming-Qing Gao, and Yong Zhang
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Medicine ,Science - Abstract
This study was performed to investigate the effects of genetically modified (GM) milk containing human beta-defensin-3 (HBD3) on mice by a 90-day feeding study. The examined parameters included the digestibility of GM milk, general physical examination, gastric emptying function, intestinal permeability, intestinal microflora composition of mice, and the possibility of horizontal gene transfer (HGT). The emphasis was placed on the effects on gastrointestinal (GI) tract due to the fact that GI tract was the first site contacting with food and played crucial roles in metabolic reactions, nutrition absorption and immunity regulation in the host. However, the traditional methods for analyzing the potential toxicological risk of GM product pay little attention on GI health. In this study, the results showed GM milk was easy to be digested in simulated gastric fluid, and it did not have adverse effects on general and GI health compared to conventional milk. And there is little possibility of HGT. This study may enrich the safety assessment of GM product on GI health.
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- 2016
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22. Development of Gene-Based SSR Markers in Rice Bean (Vigna umbellata L.) Based on Transcriptome Data.
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Honglin Chen, Xin Chen, Jing Tian, Yong Yang, Zhenxing Liu, Xiyu Hao, Lixia Wang, Suhua Wang, Jie Liang, Liya Zhang, Fengxiang Yin, and Xuzhen Cheng
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Medicine ,Science - Abstract
Rice bean (Vigna umbellata (Thunb.) Ohwi & Ohashi) is a warm season annual legume mainly grown in East Asia. Only scarce genomic resources are currently available for this legume crop species and no simple sequence repeat (SSR) markers have been specifically developed for rice bean yet. In this study, approximately 26 million high quality cDNA sequence reads were obtained from rice bean using Illumina paired-end sequencing technology and assembled into 71,929 unigenes with an average length of 986 bp. Of these unigenes, 38,840 (33.2%) showed significant similarity to proteins in the NCBI non-redundant protein and nucleotide sequence databases. Furthermore, 30,170 (76.3%) could be classified into gene ontology categories, 25,451 (64.4%) into Swiss-Prot categories and 21,982 (55.6%) into KOG database categories (E-value < 1.0E-5). A total of 9,301 (23.5%) were mapped onto 118 pathways using the Kyoto Encyclopedia of Genes and Genome (KEGG) pathway database. A total of 3,011 genic SSRs were identified as potential molecular markers. AG/CT (30.3%), AAG/CTT (8.1%) and AGAA/TTCT (20.0%) are the three main repeat motifs. A total of 300 SSR loci were randomly selected for validation by using PCR amplification. Of these loci, 23 primer pairs were polymorphic among 32 rice bean accessions. A UPGMA dendrogram revealed three major clusters among 32 rice bean accessions. The large number of SSR-containing sequences and genic SSRs in this study will be valuable for the construction of high-resolution genetic linkage maps, association or comparative mapping and genetic analyses of various Vigna species.
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- 2016
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23. The Extratropical Northern Hemisphere Temperature Reconstruction during the Last Millennium Based on a Novel Method.
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Pei Xing, Xin Chen, Yong Luo, Suping Nie, Zongci Zhao, Jianbin Huang, and Shaowu Wang
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Medicine ,Science - Abstract
Large-scale climate history of the past millennium reconstructed solely from tree-ring data is prone to underestimate the amplitude of low-frequency variability. In this paper, we aimed at solving this problem by utilizing a novel method termed "MDVM", which was a combination of the ensemble empirical mode decomposition (EEMD) and variance matching techniques. We compiled a set of 211 tree-ring records from the extratropical Northern Hemisphere (30-90°N) in an effort to develop a new reconstruction of the annual mean temperature by the MDVM method. Among these dataset, a number of 126 records were screened out to reconstruct temperature variability longer than decadal scale for the period 850-2000 AD. The MDVM reconstruction depicted significant low-frequency variability in the past millennium with evident Medieval Warm Period (MWP) over the interval 950-1150 AD and pronounced Little Ice Age (LIA) cumulating in 1450-1850 AD. In the context of 1150-year reconstruction, the accelerating warming in 20th century was likely unprecedented, and the coldest decades appeared in the 1640s, 1600s and 1580s, whereas the warmest decades occurred in the 1990s, 1940s and 1930s. Additionally, the MDVM reconstruction covaried broadly with changes in natural radiative forcing, and especially showed distinct footprints of multiple volcanic eruptions in the last millennium. Comparisons of our results with previous reconstructions and model simulations showed the efficiency of the MDVM method on capturing low-frequency variability, particularly much colder signals of the LIA relative to the reference period. Our results demonstrated that the MDVM method has advantages in studying large-scale and low-frequency climate signals using pure tree-ring data.
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- 2016
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24. HCV Diversity among Chinese and Burmese IDUs in Dehong, Yunnan, China.
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Zhenzhou Wan, Qianqian Chen, Xin Chen, Lin Duo, Peilu Li, Yong-Tang Zheng, and Chiyu Zhang
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Medicine ,Science - Abstract
HCV transmission is closely associated with drug-trafficking routes in China. Dehong, a prefecture of Yunnan, is the important trade transfer station linking Southeast Asia and China, as well as the drug-trafficking channel linking "Golden triangle" and other regions of China and surrounding countries. In this study, we investigated the HCV genotype diversity among IDUs in Dehong based on 259 HCV positive samples from 118 Chinese and 141 Burmese IDUs. HCV genotypes were determined based on the phylogenies of C/E2 and NS5B genomic sequences. Six HCV subtypes, including 1a, 1b, 3a, 3b, 6n and 6u, were detected. Interestingly, 4 HCV sequences from Burmese IDUs did not cluster with any known HCV subtypes, but formed a well-supported independent clade in the phylogenetic trees of both C/E2 and NS5B, suggesting a potential new HCV subtype circulating in Dehong. Subtype 3b was the predominant subtype, followed by subtypes 6n and 6u. Comparison showed that Dehong had a unique pattern of HCV subtype distribution, obviously different from other regions of China. In particular, HCV subtypes 6u and the potential new HCV subtype had a relatively high prevalence in Dehong, but were rarely detected in other regions of China. There was no significant difference in HCV subtype distribution between Burmese and Chinese IDUs. Few HCV sequences from Burmese and Chinese IDUs clustered together to form transmission clusters. Furthermore, about half of HCV sequences from Burmese IDUs formed small transmission clusters, significantly higher than that from Chinese IDUs (p
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- 2016
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25. Erectile Dysfunction in Chronic Prostatitis/Chronic Pelvic Pain Syndrome: Outcomes from a Multi-Center Study and Risk Factor Analysis in a Single Center.
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Yadong Zhang, Tao Zheng, Xiang'an Tu, Xin Chen, Zhu Wang, Shengfu Chen, Qiyun Yang, Zi Wan, Dayu Han, Haipeng Xiao, Xiangzhou Sun, and Chunhua Deng
- Subjects
Medicine ,Science - Abstract
The aim of this study was to investigate the prevalence of erectile dysfunction (ED) in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) and explore the influence of UPOINT domains, National Institutes of Health-CP symptom index (NIH-CPSI) and other factors on ED prevalence. This was a prospective study of consecutive patients with CP/CPPS seen at 11 tertiary hospitals during January-July 2014. ED was diagnosed as a score of
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- 2016
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26. OFD1, as a Ciliary Protein, Exhibits Neuroprotective Function in Photoreceptor Degeneration Models.
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Juan Wang, Xin Chen, Fang Wang, Jieping Zhang, Peng Li, Zongyi Li, Jingying Xu, Furong Gao, Caixia Jin, Haibin Tian, Jingfa Zhang, Weiye Li, Lixia Lu, and Guo-Tong Xu
- Subjects
Medicine ,Science - Abstract
Ofd1 is a newly identified causative gene for Retinitis pigmentosa (RP), a photoreceptor degenerative disease. This study aimed to examine Ofd1 localization in retina and further to investigate its function in photoreceptor degeneration models. Ofd1 localization in rat retina was examined using immunofluorescence. N-methyl-N-nitrosourea (MNU)-induced rats and Royal College of Surgeons (RCS) rats were used as photoreceptor degeneration models. The expression pattern of Ofd1, other ciliary associated genes and Wnt signaling pathway genes were examined in rat models. Furthermore, pEGFP-Ofd1-CDS and pSUPER-Ofd1-shRNA were constructed to overexpress and knockdown the expression level in 661W and R28 cells. MNU was also used to induce cell death. Cilia formation was observed using immunocytochemistry (ICC). Reactive oxygen species (ROS) were detected using the 2', 7'-Dichlorofluorescin diacetate (DCFH-DA) assay. Apoptosis genes expression was examined using qRT-PCR, Western blotting and fluorescence-activated cell sorting (FACS). Ofd1 localized to outer segments of rat retina photoreceptors. Ofd1 and other ciliary proteins expression levels increased from the 1st and 4th postnatal weeks and decreased until the 6th week in the RCS rats, while their expression consistently decreased from the 1st and 7th day in the MNU rats. Moreover, Wnt signaling pathway proteins expression was significantly up-regulated in both rat models. Knockdown of Ofd1 expression resulted in a smaller population, shorter length of cell cilia, and lower cell viability. Ofd1 overexpression partially attenuated MNU toxic effects by reducing ROS levels and mitigating apoptosis. To the best of our knowledge, this is the first study demonstrating Ofd1 localization and its function in rat retina and in retinal degeneration rat models. Ofd1 plays a role in controlling photoreceptor cilium length and number. Importantly, it demonstrates a neuroprotective function by protecting the photoreceptor from oxidative stress and apoptosis. These data have expanded our understanding of Ofd1 function beyond cilia, and we concluded that ofd1 neuroprotection could be a potential treatment strategy in retina degeneration models.
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- 2016
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27. The Gametocytes of Leucocytozoon sabrazesi Infect Chicken Thrombocytes, Not Other Blood Cells.
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Wenting Zhao, Jianwen Liu, Ruixue Xu, Cui Zhang, Qin Pang, Xin Chen, Shengfa Liu, Lingxian Hong, Jing Yuan, Xiaotong Li, Yixin Chen, Jian Li, and Xin-Zhuan Su
- Subjects
Medicine ,Science - Abstract
Leucocytozoon parasites infect a large number of avian hosts, including domestic chicken, and cause significant economical loss to the poultry industry. Although the transmission stages of the parasites were observed in avian blood cells more than a century ago, the specific host cell type(s) that the gametocytes infect remain uncertain. Because all the avian blood cells, including red blood cells (RBCs), are nucleated, and the developing parasites dramatically change the morphology of the infected host cells, it has been difficult to identify Leucocytozoon infected host cell(s). Here we use cell-type specific antibodies to investigate the identities of the host cells infected by Leucocytozoon sabrazesi gametocytes. Anti-RBC antibodies stained RBCs membrane strongly, but not the parasite-infected cells, ruling out the possibility of RBCs being the infected host cells. Antibodies recognizing various leukocytes including heterophils, monocytes, lymphocytes, and macrophages did not stain the infected cells either. Antisera raised against a peptide of the parasite cytochrome B (CYTB) stained parasite-infected cells and some leukocytes, particularly cells with a single round nucleus as well as clear/pale cytoplasm suggestive of thrombocytes. Finally, a monoclonal antibody known to specifically bind chicken thrombocytes also stained the infected cells, confirming that L. sabrazesi gametocytes develop within chicken thrombocytes. The identification of L. sabrazesi infected host cell solves a long unresolved puzzle and provides important information for studying parasite invasion of host cells and for developing reagents to interrupt parasite transmission.
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- 2015
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28. Comparative Transcriptome Analysis of Differentially Expressed Genes and Signaling Pathways between XY and YY Testis in Yellow Catfish.
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Junjie Wu, Shuting Xiong, Jing Jing, Xin Chen, Weimin Wang, Jian-Fang Gui, and Jie Mei
- Subjects
Medicine ,Science - Abstract
YY super-males have rarely been detected in nature and only been artificially created in some fish species including tilapia and yellow catfish (Pelteobagrusfulvidraco), which provides a promising model for testis development and spermatogenesis. In our previous study, significant differences in morphology and miRNA expression were detected between XY and YY testis of yellow catfish. Here, solexa sequencing technology was further performed to compare mRNA expression between XY and YY testis. Compared with unigenes expressed in XY testis, 1146 and 1235 unigenes have significantly higher and lower expression in YY testis, respectively. 605 differentially expressed unigenes were annotated to 1604 GO terms with 319 and 286 genes having relative higher expression in XY and YY testis. KEGG analysis suggested different levels of PI3K-AKT and G protein-coupled receptor (GPCR) signaling pathways between XY and YY testis. Down-regulation of miR-141/429 in YY testis was speculated to promote testis development and maturation, and several factors in PI3K-AKT and GPCR signaling pathways were found as predicted targets of miR-141/429, several of which were confirmed by dual-luciferase reporter assays. Our study provides a comparative transcriptome analysis between XY and YY testis, and reveals interactions between miRNAs and their target genes that are possibly involved in regulating testis development and spermatogenesis.
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- 2015
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29. Long-Term Dynamical Constraints on Pharmacologically Evoked Potentiation Imply Activity Conservation within In Vitro Hippocampal Networks.
- Author
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Mark Niedringhaus, Xin Chen, and Rhonda Dzakpasu
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Medicine ,Science - Abstract
This paper describes a long-term study of network dynamics from in vitro, cultured hippocampal neurons after a pharmacological induction of synaptic potentiation. We plate a suspension of hippocampal neurons on an array of extracellular electrodes and record electrical activity in the absence of the drugs several days after treatment. While previous studies have reported on potentiation lasting up to a few hours after treatment, to the best of our knowledge, this is the first report to characterize the network effects of a potentiating mechanism several days after treatment. Using this reduced, two-dimensional in vitro network of hippocampal neurons, we show that the effects of potentiation are persistent over time but are modulated under a conservation of spike principle. We suggest that this conservation principle might be mediated by the appearance of a resonant inter-spike interval that prevents the network from advancing towards a state of hyperexcitability.
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- 2015
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30. Overexpression of periostin in stroma positively associated with aggressive prostate cancer.
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Yuan Tian, Caitlin H Choi, Qing Kay Li, Farah B Rahmatpanah, Xin Chen, Sara Ruth Kim, Robert Veltri, David Chia, Zhen Zhang, Dan Mercola, and Hui Zhang
- Subjects
Medicine ,Science - Abstract
Periostin is an important extracellular matrix protein involved in cell development and adhesion. Previously, we identified periostin to be up-regulated in aggressive prostate cancer (CaP) using quantitative glycoproteomics and mass spectrometry. The expression of periostin was further evaluated in primary radical prostatectomy (RP) prostate tumors and adjacent non-tumorous prostate tissues using immunohistochemistry (IHC). Our IHC results revealed a low background periostin levels in the adjacent non-tumorous prostate tissues, but overexpressed periostin levels in the peritumoral stroma of primary CaP tumors.In this study, periostin expression in CaP was further examined on multiple tissue microarrays (TMAs), which were conducted in four laboratories. To achieve consistent staining, all TMAs were stained with same protocol and scored by same image computation tool to determine the total periostin staining intensities. The TMAs were further scored by pathologists to characterize the stromal staining and epithelial staining.The periostin staining was observed mainly in peritumoral stromal cells and in some cases in tumor epithelial cells though the stronger staining was found in peritumoral stromal cells. Both periostin stromal staining and epithelial staining can differentiate BPH from CaP including low grade CaP (Gleason score ≤6), with significant p-value of 2.2e-16 and 0.001, respectively. Periostin epithelial staining differentiated PIN from low grade CaP (Gleason score ≤6) (p=0.001), while periostin stromal staining differentiated low grade Cap (Gleason score ≤6) from high grade Cap (Gleason score ≤6) (p=1.7e-05). In addition, a positive correlation between total periostin staining and Gleason score was observed (r=0.87, p=0.002).The results showed that periostin staining was positively correlated with increasing Gleason score and the aggressiveness of prostate disease.
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- 2015
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31. Expression and Functional Analysis of WRKY Transcription Factors in Chinese Wild Hazel, Corylus heterophylla Fisch.
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Tian-Tian Zhao, Jin Zhang, Li-Song Liang, Qing-Hua Ma, Xin Chen, Jian-Wei Zong, and Gui-Xi Wang
- Subjects
Medicine ,Science - Abstract
Plant WRKY transcription factors are known to regulate various biotic and abiotic stress responses. In this study we identified a total of 30 putative WRKY unigenes in a transcriptome dataset of the Chinese wild Hazel, Corylus heterophylla, a species that is noted for its cold tolerance. Thirteen full-length of these ChWRKY genes were cloned and found to encode complete protein sequences, and they were divided into three groups, based on the number of WRKY domains and the pattern of zinc finger structures. Representatives of each of the groups, Unigene25835 (group I), Unigene37641 (group II) and Unigene20441 (group III), were transiently expressed as fusion proteins with yellow fluorescent fusion protein in Nicotiana benthamiana, where they were observed to accumulate in the nucleus, in accordance with their predicted roles as transcriptional activators. An analysis of the expression patterns of all 30 WRKY genes revealed differences in transcript abundance profiles following exposure to cold, drought and high salinity conditions. Among the stress-inducible genes, 23 were up-regulated by all three abiotic stresses and the WRKY genes collectively exhibited four different patterns of expression in flower buds during the overwintering period from November to April. The organ/tissue related expression analysis showed that 18 WRKY genes were highly expressed in stem but only 2 (Unigene9262 and Unigene43101) were greatest in male anthotaxies. The expression of Unigene37641, a member of the group II WRKY genes, was substantially up-regulated by cold, drought and salinity treatments, and its overexpression in Arabidopsis thaliana resulted in better seedling growth, compared with wild type plants, under cold treatment conditions. The transgenic lines also had exhibited higher soluble protein content, superoxide dismutase and peroxidase activiety and lower levels of malondialdehyde, which collectively suggets that Unigene37641 expression promotes cold tolerance.
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- 2015
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32. Correction: Overexpression of periostin in stroma positively associated with aggressive prostate cancer.
- Author
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Yuan Tian, Caitlin H Choi, Qing Kay Li, Farah B Rahmatpanah, Xin Chen, Sara Ruth Kim, Robert Veltri, David Chia, Zhen Zhang, Dan Mercola, and Hui Zhang
- Subjects
Medicine ,Science - Published
- 2015
- Full Text
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33. Molecular Cloning and Characterisation of Farnesyl Pyrophosphate Synthase from Tripterygium wilfordii.
- Author
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Yu-Jun Zhao, Xin Chen, Meng Zhang, Ping Su, Yu-Jia Liu, Yu-Ru Tong, Xiu-Juan Wang, Lu-Qi Huang, and Wei Gao
- Subjects
Medicine ,Science - Abstract
Farnesylpyrophosphate synthase (FPS) catalyzes the biosynthesis of farnesyl pyrophosphate (FPP), which is an important precursor of sesquiterpenoids such as artemisinin and wilfordine. In the present study, we report the molecular cloning and characterization of two full-length cDNAs encoding FPSs from Tripterygium wilfordii (TwFPSs). TwFPSs maintained their capability to synthesise FPP in vitro when purified as recombinant proteins from E. coli. Consistent with the endogenous role of FPS in FPP biosynthesis, TwFPSs were highly expressed in T. wilfordii roots, and were up-regulated upon methyl jasmonate (MeJA) treatment. The global gene expression profiles suggested that the TwFPSs might play an important regulatory role interpenoid biosynthesis in T. wilfordii, laying the groundwork for the future study of the synthetic biology of natural terpene products.
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- 2015
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34. The influence of maternal islet beta-cell autoantibodies in conjunction with gestational hyperglycemia on neonatal outcomes.
- Author
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Zhe Li, Tian-mei Wu, Wei-jie Ming, Xin Chen, and Xiao-min Xiao
- Subjects
Medicine ,Science - Abstract
To determine the predictive value of the presence of maternal islet beta-cell autoantibodies with respect to neonatal outcomes.A total of 311 pregnant women with abnormal 75 g oral glucose tolerance test (OGTT) results were enrolled in this study. Maternal glutamic acid decarboxylase autoantibodies (GADA), islet cell autoantibodies (ICA) and insulin autoantibodies (IAA) were tested in fasting blood both on the day following the routine OGTT and before delivery. The birth weight, Apgar score, blood glucose and outcomes of each neonate were later evaluated and recorded.1. In this study, 33.9% of the pregnant women with gestational hyperglycemia had detectable levels of one or more types of anti-islet cell antibodies in the third trimester. The proportion of women who produced GADA and/or ICA was significantly higher in the group of women with gestational hyperglycemia than in the control group (P
- Published
- 2015
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35. Higher urinary bisphenol A concentration is associated with unexplained recurrent miscarriage risk: evidence from a case-control study in eastern China.
- Author
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Yueping Shen, Yanmin Zheng, Jingting Jiang, Yinmei Liu, Xiaoming Luo, Zongji Shen, Xin Chen, Yan Wang, Yiheng Dai, Jing Zhao, Hong Liang, Aimin Chen, and Wei Yuan
- Subjects
Medicine ,Science - Abstract
Evidence about the association between Bisphenol A (BPA) and the risk of recurrent miscarriage (RM) in human being is still limited.We evaluated the association of urinary BPA concentrations with RM in human being.A hospital-based 1:2 matched case-control study on RM was carried out in Suzhou and Kunshan in Jiangsu Province in China between August 2008 and November 2011. Total urinary BPA concentrations in 264 eligible urine samples (102 RM patients and 162 controls) were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The Wilcoxon test and conditional logistic regression were used to estimate the differences between the groups and odds ratios (OR) with 95% confidence intervals (CI), respectively.The median ± IQR (interquartile range) (P75-P25) values of non-creatinine-adjusted total urinary BPA levels in the RM patients and the controls were 1.66 ± 3.69 ng/ml and 0.58 ± 1.07 ng/ml, respectively (0.98 ± 2.67 μg/g Cr (creatinine) and 0.40 ± 0.77 μg/g Cr. The adjusted BPA level was significantly higher in the RM patients than in the controls (Wilcoxon test, Z = 4.476, P < 0.001). Higher level of urinary BPA was significantly associated with an increased risk of RM (P-trend < 0.001). Compared to the groups with urinary BPA levels less than 0.16 μg/g Cr, the women with levels of 0.40-0.93 μg/g Cr and 0.93 μg/g Cr or above had a significantly higher risk of RM (OR = 3.91, 95%CI: 1.23-12.45 and OR = 9.34, 95%CI: 3.06-28.44) that persisted after adjusting for confounding factors. The time from recently RM date to recruitment does not significantly influence the urinary BPA level (P = 0.090).Exposure to BPA may be associated with RM risk.
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- 2015
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36. Adverse Effects of High Concentrations of Fluoride on Characteristics of the Ovary and Mature Oocyte of Mouse.
- Author
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Songna Yin, Chao Song, Haibo Wu, Xin Chen, and Yong Zhang
- Subjects
Medicine ,Science - Abstract
Reproductive toxicity has been an exciting topic of research in reproductive biology in recent years. Soluble fluoride salts are toxic at high concentrations; their reproductive toxicity was assessed in this study by administering different fluoride salt concentrations to mice. Continuous feeding for five weeks resulted in damage to the histological architecture of ovaries. The expression of genes, including Dazl, Stra8, Nobox, Sohlh1, and ZP3 gene, associated with oocyte formation were much lower in the experimental group as compared with the control group. The number of in vitro fertilization of mature oocytes were also much lower in the experimental group as compared with control. Moreover, the fertility of female mice, as assessed by mating with normal male mice, was also lower in experimental compared with control groups. The expression of the oocyte-specific genes: Bmp15, Gdf9, H1oo, and ZP2, which are involved in oocyte growth and the induction of the acrosome reaction, decreased with the fluoride administration. DNA methylation and histone acetylation (H3K18ac and H3K9ac) are indispensable for germline development and genomic imprinting in mammals, and fluoride administration resulted in reduced levels of H3K9ac and H3K18ac in the experimental group as compared with the control group, as detected by immunostaining. Our results indicate that the administration of high concentrations of fluoride to female mice significantly reduced the number of mature oocytes and hampered their development and fertilization. Thus, this study lays a foundation for future studies on fluoride-induced reproductive disorders in women.
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- 2015
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37. Comparative transcriptome analysis of genes involved in anthocyanin biosynthesis in the red and yellow fruits of sweet cherry (Prunus avium L.).
- Author
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Hairong Wei, Xin Chen, Xiaojuan Zong, Huairui Shu, Dongsheng Gao, and Qingzhong Liu
- Subjects
Medicine ,Science - Abstract
Fruit color is one of the most important economic traits of the sweet cherry (Prunus avium L.). The red coloration of sweet cherry fruit is mainly attributed to anthocyanins. However, limited information is available regarding the molecular mechanisms underlying anthocyanin biosynthesis and its regulation in sweet cherry.In this study, a reference transcriptome of P. avium L. was sequenced and annotated to identify the transcriptional determinants of fruit color. Normalized cDNA libraries from red and yellow fruits were sequenced using the next-generation Illumina/Solexa sequencing platform and de novo assembly. Over 66 million high-quality reads were assembled into 43,128 unigenes using a combined assembly strategy. Then a total of 22,452 unigenes were compared to public databases using homology searches, and 20,095 of these unigenes were annotated in the Nr protein database. Furthermore, transcriptome differences between the four stages of fruit ripening were analyzed using Illumina digital gene expression (DGE) profiling. Biological pathway analysis revealed that 72 unigenes were involved in anthocyanin biosynthesis. The expression patterns of unigenes encoding phenylalanine ammonia-lyase (PAL), 4-coumarate-CoA ligase (4CL), chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), flavanone 3'-hydroxylase (F3'H), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase (ANS) and UDP glucose: flavonol 3-O-glucosyltransferase (UFGT) during fruit ripening differed between red and yellow fruit. In addition, we identified some transcription factor families (such as MYB, bHLH and WD40) that may control anthocyanin biosynthesis. We confirmed the altered expression levels of eighteen unigenes that encode anthocyanin biosynthetic enzymes and transcription factors using quantitative real-time PCR (qRT-PCR).The obtained sweet cherry transcriptome and DGE profiling data provide comprehensive gene expression information that lends insights into the molecular mechanisms underlying anthocyanin biosynthesis. These results will provide a platform for further functional genomic research on this fruit crop.
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- 2015
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38. Calpain inhibitor PD150606 attenuates glutamate induced spiral ganglion neuron apoptosis through apoptosis inducing factor pathway in vitro.
- Author
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Zhong-Jia Ding, Xin Chen, Xiao-Xu Tang, Xi Wang, Yong-Li Song, Xiao-Dong Chen, Wen-Juan Mi, Jian Wang, Ying Lin, Fu-Quan Chen, and Jian-Hua Qiu
- Subjects
Medicine ,Science - Abstract
This research aimed to investigate whether glutamate induced spiral ganglion neurons (SGNs) apoptosis through apoptosis inducing factor (AIF) pathway. And verify whether PD150606, a calpain inhibitor could prevent apoptosis by inhibiting cleaving and releasing AIF in mitochondrion.SGNs of postnatal days 0-3 were harvested and cultured in dishes. 20 mM Glu, the caspase inhibitor Z-VAD-FMK and calpain inhibitor PD150606 were added into cultured dishes separately. We used optical microscope and immunofluoresence staining to observe cell morphology and AIF distribution, RT-PCR and Westernblot to analyse AIF and calpain expression in SGNs. TUNEL assay was used to test cell apoptosis.Cell morphology and nuclear translocation of AIF were altered in SGNs by 20 mM Glu treated in vitro. The axon of SGN shortened, more apoptosis SGN were observed and the expression of AIF and calpain were up-regulated in Glu-treated group than the normal one (P
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- 2015
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39. Administration of BMSCs with muscone in rats with gentamicin-induced AKI improves their therapeutic efficacy.
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Pengfei Liu, Yetong Feng, Chao Dong, Dandan Yang, Bo Li, Xin Chen, Zhongjun Zhang, Yi Wang, Yulai Zhou, and Lei Zhao
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Medicine ,Science - Abstract
The therapeutic action of bone marrow-derived mesenchymal stem cells (BMSCs) in acute kidney injury (AKI) has been reported by several groups. However, recent studies indicated that BMSCs homed to kidney tissues at very low levels after transplantation. The lack of specific homing of exogenously infused cells limited the effective implementation of BMSC-based therapies. In this study, we provided evidence that the administration of BMSCs combined with muscone in rats with gentamicin-induced AKI intravenously, was a feasible strategy to drive BMSCs to damaged tissues and improve the BMSC-based therapeutic effect. The effect of muscone on BMSC bioactivity was analyzed in vitro and in vivo. The results indicated that muscone could promote BMSC migration and proliferation. Some secretory capacity of BMSC still could be improved in some degree. The BMSC-based therapeutic action was ameliorated by promoting the recovery of biochemical variables in urine or blood, as well as the inhibition of cell apoptosis and inflammation. In addition, the up-regulation of CXCR4 and CXCR7 expression in BMSCs could be the possible mechanism of muscone amelioration. Thus, our study indicated that enhancement of BMSCs bioactivities with muscone could increase the BMSC therapeutic potential and further developed a new therapeutic strategy for the treatment of AKI.
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- 2014
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40. A functional polymorphism C-509T in TGFβ-1 promoter contributes to susceptibility and prognosis of lone atrial fibrillation in Chinese population.
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Hailong Cao, Qing Zhou, Rongfang Lan, Oluf Dimitri Røe, Xin Chen, Yijiang Chen, and Dongjin Wang
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Medicine ,Science - Abstract
Transforming growth factor-β1 (TGF-β1) is an important mediator of atrial fibrosis and atrial fibrillation (AF). But the involved genetic mechanism is unknown. Herein, the TGF-β1 C-509 T polymorphism (rs1800469) was genotyped in a case-control study of 840 patients and 845 controls in Chinese population to explore the association between the polymorphism and susceptibility and prognosis of lone AF. As a result, the CT and/or TT genotypes had an increased lone AF risk [adjusted odds ratio (OR) = 1.50 for CT, OR = 3.72 for TT, and OR = 2.15 for CT/TT], compared with the TGF-β1CC genotype. Moreover, patients carrying CT/TT genotypes showed a higher possibility of AF recurrence after catheter ablation, compared with patients carrying CC genotype. In a genotype-phenotype correlation analysis using 24 normal left atrial appendage samples, increasing gradients of atrial TGF-β1 expression levels positively correlated with atrial collagen volume fraction were identified in samples with CC, CT and TT genotypes. The in vitro luciferase assays also showed a higher luciferase activity of the -509 T allele than that of the -509 C allele. In conclusion, the TGF-β1 C-509 T polymorphism is involved in the etiology of lone AF and thus may be a marker for genetic susceptibility to lone AF and predicting prognosis after catheter ablation in Chinese populations. Therefore, we provide new information about treatment strategies and our understanding of TGF-β1 in AF.
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- 2014
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41. Generation of 'virtual' control groups for single arm prostate cancer adjuvant trials.
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Zhenyu Jia, Michael B Lilly, James A Koziol, Xin Chen, Xiao-Qin Xia, Yipeng Wang, Douglas Skarecky, Manuel Sutton, Anne Sawyers, Herbert Ruckle, Philip M Carpenter, Jessica Wang-Rodriguez, Jun Jiang, Mingsen Deng, Cong Pan, Jian-Guo Zhu, Christine E McLaren, Michael J Gurley, Chung Lee, Michael McClelland, Thomas Ahlering, Michael W Kattan, and Dan Mercola
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Medicine ,Science - Abstract
It is difficult to construct a control group for trials of adjuvant therapy (Rx) of prostate cancer after radical prostatectomy (RP) due to ethical issues and patient acceptance. We utilized 8 curve-fitting models to estimate the time to 60%, 65%, … 95% chance of progression free survival (PFS) based on the data derived from Kattan post-RP nomogram. The 8 models were systematically applied to a training set of 153 post-RP cases without adjuvant Rx to develop 8 subsets of cases (reference case sets) whose observed PFS times were most accurately predicted by each model. To prepare a virtual control group for a single-arm adjuvant Rx trial, we first select the optimal model for the trial cases based on the minimum weighted Euclidean distance between the trial case set and the reference case set in terms of clinical features, and then compare the virtual PFS times calculated by the optimum model with the observed PFSs of the trial cases by the logrank test. The method was validated using an independent dataset of 155 post-RP patients without adjuvant Rx. We then applied the method to patients on a Phase II trial of adjuvant chemo-hormonal Rx post RP, which indicated that the adjuvant Rx is highly effective in prolonging PFS after RP in patients at high risk for prostate cancer recurrence. The method can accurately generate control groups for single-arm, post-RP adjuvant Rx trials for prostate cancer, facilitating development of new therapeutic strategies.
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- 2014
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42. Transcriptome assembly and analysis of Tibetan Hulless Barley (Hordeum vulgare L. var. nudum) developing grains, with emphasis on quality properties.
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Xin Chen, Hai Long, Ping Gao, Guangbing Deng, Zhifen Pan, Junjun Liang, Yawei Tang, Nyima Tashi, and Maoqun Yu
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Medicine ,Science - Abstract
BACKGROUND: Hulless barley is attracting increasing attention due to its unique nutritional value and potential health benefits. However, the molecular biology of the barley grain development and nutrient storage are not well understood. Furthermore, the genetic potential of hulless barley has not been fully tapped for breeding. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we investigated the transcriptome features during hulless barley grain development. Using Illumina paired-end RNA-Sequencing, we generated two data sets of the developing grain transcriptomes from two hulless barley landraces. A total of 13.1 and 12.9 million paired-end reads with lengths of 90 bp were generated from the two varieties and were assembled to 48,863 and 45,788 unigenes, respectively. A combined dataset of 46,485 All-Unigenes were generated from two transcriptomes with an average length of 542 bp, and 36,278 among were annotated with gene descriptions, conserved protein domains or gene ontology terms. Furthermore, sequences and expression levels of genes related to the biosynthesis of storage reserve compounds (starch, protein, and β-glucan) were analyzed, and their temporal and spatial patterns were deduced from the transcriptome data of cultivated barley Morex. CONCLUSIONS/SIGNIFICANCE: We established a sequences and functional annotation integrated database and examined the expression profiles of the developing grains of Tibetan hulless barley. The characterization of genes encoding storage proteins and enzymes of starch synthesis and (1-3;1-4)-β-D-glucan synthesis provided an overview of changes in gene expression associated with grain nutrition and health properties. Furthermore, the characterization of these genes provides a gene reservoir, which helps in quality improvement of hulless barley.
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- 2014
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43. Maduramicin inhibits proliferation and induces apoptosis in myoblast cells.
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Xin Chen, Ying Gu, Karnika Singh, Chaowei Shang, Mansoureh Barzegar, Shanxiang Jiang, and Shile Huang
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Medicine ,Science - Abstract
Maduramicin, a polyether ionophore antibiotic derived from the bacterium Actinomadura yumaensis, is currently used as a feed additive against coccidiosis in poultry worldwide. It has been clinically observed that maduramicin can cause skeletal muscle and heart cell damage, resulting in skeletal muscle degeneration, heart failure, and even death in animals and humans, if improperly used. However, the mechanism of its toxic action in myoblasts is not well understood. Using mouse myoblasts (C2C12) and human rhabdomyosarcoma (RD and Rh30) cells as an experimental model for myoblasts, here we found that maduramicin inhibited cell proliferation and induced cell death in a concentration-dependent manner. Further studies revealed that maduramicin induced accumulation of the cells at G0/G1 phase of the cell cycle, and induced apoptosis in the cells. Concurrently, maduramicin downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and CDC25A, and upregulated expression of the CDK inhibitors (p21Cip1 and p27Kip1), resulting in decreased phosphorylation of Rb. Maduramicin also induced expression of BAK, BAD, DR4, TRADD and TRAIL, leading to activation of caspases 8, 9 and 3 as well as cleavage of poly ADP ribose polymerase (PARP). Taken together, our results suggest that maduramicin executes its toxicity in myoblasts at least by inhibiting cell proliferation and inducing apoptotic cell death.
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- 2014
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44. Fusarochromanone induces G1 cell cycle arrest and apoptosis in COS7 and HEK293 cells.
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Ying Gu, Xin Chen, Chaowei Shang, Karnika Singh, Mansoureh Barzegar, Elahe Mahdavian, Brian A Salvatore, Shanxiang Jiang, and Shile Huang
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Medicine ,Science - Abstract
Fusarochromanone (FC101), a mycotoxin produced by the fungus Fusarium equiseti, is frequently observed in the contaminated grains and feedstuffs, which is toxic to animals and humans. However, the underlying molecular mechanism remains to be defined. In this study, we found that FC101 inhibited cell proliferation and induced cell death in COS7 and HEK293 cells in a concentration-dependent manner. Flow cytometric analysis showed that FC101 induced G1 cell cycle arrest and apoptosis in the cells. Concurrently, FC101 downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and Cdc25A, and upregulated expression of the CDK inhibitors (p21Cip1 and p27Kip1), resulting in hypophosphorylation of Rb. FC101 also inhibited protein expression of Bcl-2, Bcl-xL, Mcl-1 and survivin, and induced expression of BAD, leading to activation of caspase 3 and cleavage of PARP, indicating caspase-dependent apoptosis. However, Z-VAD-FMK, a pan-caspase inhibitor, only partially prevented FC101-induced cell death, implying that FC101 may induce cell death through both caspase-dependent and -independent mechanisms. Our results support the notion that FC101 executes its toxicity at least by inhibiting cell proliferation and inducing cell death.
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- 2014
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45. EDEM2 and OS-9 are required for ER-associated degradation of non-glycosylated sonic hedgehog.
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Hsiang-Yun Tang, Chih-Hsiang Huang, Ya-Han Zhuang, John C Christianson, and Xin Chen
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Medicine ,Science - Abstract
Misfolded proteins of the endoplasmic reticulum (ER) are eliminated by the ER-associated degradation (ERAD) in eukaryotes. In S. cerevisiae, ER-resident lectins mediate substrate recognition through bipartite signals consisting of an unfolded local structure and the adjacent glycan. Trimming of the glycan is essential for the directional delivery of the substrates. Whether a similar recognition and delivery mechanism exists in mammalian cells is unknown. In this study, we systematically study the function and substrate specificity of known mammalian ER lectins, including EDEM1/2/3, OS-9 and XTP-3B using the recently identified ERAD substrate sonic hedgehog (SHH), a soluble protein carrying a single N-glycan, as well as its nonglycosylated mutant N278A. Efficient ERAD of N278A requires the core processing complex of HRD1, SEL1L and p97, similar to the glycosylated SHH. While EDEM2 was required for ERAD of both glycosylated and non-glycosylated SHHs, EDEM3 was only necessary for glycosylated SHH and EDEM1 was dispensable for both. Degradation of SHH and N278A also required OS-9, but not the related lectin XTP3-B. Robust interaction of both EDEM2 and OS-9 with a non-glycosylated SHH variant indicates that the misfolded polypeptide backbone, rather than a glycan signature, functions as the predominant signal for recognition for ERAD. Notably, SHH-N278A is the first nonglycosylated substrate to require EDEM2 for recognition and targeting for ERAD. EDEM2 also interacts with calnexin and SEL1L, suggesting a potential avenue by which misfolded glycoproteins may be shunted towards SEL1L and ERAD rather than being released into the secretory pathway. Thus, ER lectins participate in the recognition and delivery of misfolded ER substrates differently in mammals, with an underlying mechanism distinct from that of S. cerevisiae.
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- 2014
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46. Fibroblast activation protein (FAP) is essential for the migration of bone marrow mesenchymal stem cells through RhoA activation.
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Kuei-Min Chung, Shu-Ching Hsu, Yue-Ru Chu, Mei-Yao Lin, Weir-Tong Jiaang, Ruey-Hwa Chen, and Xin Chen
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Medicine ,Science - Abstract
BACKGROUND: The ability of human bone marrow mesenchymal stem cells (BM-MSCs) to migrate and localize specifically to injured tissues is central in developing therapeutic strategies for tissue repair and regeneration. Fibroblast activation protein (FAP) is a cell surface serine protease expressed at sites of tissue remodeling during embryonic development. It is also expressed in BM-MSCs, but not in normal tissues or cells. The function of FAP in BM-MSCs is not known. PRINCIPAL FINDINGS: We found that depletion of FAP proteins significantly inhibited the migration of BM-MSCs in a transwell chemotaxis assay. Such impaired migration ability of BM-MSCs could be rescued by re-expressing FAP in these cells. We then demonstrated that depletion of FAP activated intracellular RhoA GTPase. Consistently, inhibition of RhoA activity using a RhoA inhibitor rescued its migration ability. Inhibition of FAP activity with an FAP-specific inhibitor did not affect the activation of RhoA or the migration of BM-MSCs. Furthermore, the inflammatory cytokines interleukin-1beta (IL-1β) and transforming growth factor-beta (TGF-β) upregulated FAP expression, which coincided with better BM-MSC migration. CONCLUSIONS: Our results indicate FAP plays an important role in the migration of BM-MSCs through modulation of RhoA GTPase activity. The peptidase activity of FAP is not essential for such migration. Cytokines IL-1β and TGF-β upregulate the expression level of FAP and thus enhance BM-MSC migration.
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- 2014
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47. Allelic variations at four major maturity E genes and transcriptional abundance of the E1 gene are associated with flowering time and maturity of soybean cultivars.
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Hong Zhai, Shixiang Lü, Yueqiang Wang, Xin Chen, Haixiang Ren, Jiayin Yang, Wen Cheng, Chunmei Zong, Heping Gu, Hongmei Qiu, Hongyan Wu, Xingzheng Zhang, Tingting Cui, and Zhengjun Xia
- Subjects
Medicine ,Science - Abstract
The time to flowering and maturity are ecologically and agronomically important traits for soybean landrace and cultivar adaptation. As a typical short-day crop, long day conditions in the high-latitude regions require soybean cultivars with photoperiod insensitivity that can mature before frost. Although the molecular basis of four major E loci (E1 to E4) have been deciphered, it is not quite clear whether, or to what degree, genetic variation and the expression level of the four E genes are associated with the time to flowering and maturity of soybean cultivars. In this study, we genotyped 180 cultivars at E1 to E4 genes, meanwhile, the time to flowering and maturity of those cultivars were investigated at six geographic locations in China from 2011 to 2012 and further confirmed in 2013. The percentages of recessive alleles at E1, E2, E3 and E4 loci were 38.34%, 84.45%, 36.33%, and 7.20%, respectively. Statistical analysis showed that allelic variations at each of four loci had a significant effect on flowering time as well as maturity. We classified the 180 cultivars into eight genotypic groups based on allelic variations of the four major E loci. The genetic group of e1-nf representing dysfunctional alleles at the E1 locus flowered earliest in all the geographic locations. In contrast, cultivars in the E1E2E3E4 group originated from the southern areas flowered very late or did not flower before frost at high latitude locations. The transcriptional abundance of functional E1 gene was significantly associated with flowering time. However, the ranges of time to flowering and maturity were quite large within some genotypic groups, implying the presence of some other unknown genetic factors that are involved in control of flowering time or maturity. Known genes (e.g. E3 and E4) and other unknown factors may function, at least partially, through regulation of the expression of the E1 gene.
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- 2014
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48. Transcriptome sequencing and identification of cold tolerance genes in hardy Corylus species (C. heterophylla Fisch) floral buds.
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Xin Chen, Jin Zhang, Qingzhong Liu, Wei Guo, Tiantian Zhao, Qinghua Ma, and Guixi Wang
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Medicine ,Science - Abstract
BACKGROUND: The genus Corylus is an important woody species in Northeast China. Its products, hazelnuts, constitute one of the most important raw materials for the pastry and chocolate industry. However, limited genetic research has focused on Corylus because of the lack of genomic resources. The advent of high-throughput sequencing technologies provides a turning point for Corylus research. In the present study, we performed de novo transcriptome sequencing for the first time to produce a comprehensive database for the Corylus heterophylla Fisch floral buds. RESULTS: The C. heterophylla Fisch floral buds transcriptome was sequenced using the Illumina paired-end sequencing technology. We produced 28,930,890 raw reads and assembled them into 82,684 contigs. A total of 40,941 unigenes were identified, among which 30,549 were annotated in the NCBI Non-redundant (Nr) protein database and 18,581 were annotated in the Swiss-Prot database. Of these annotated unigenes, 25,311 and 10,514 unigenes were assigned to gene ontology (GO) categories and clusters of orthologous groups (COG), respectively. We could map 17,207 unigenes onto 128 pathways using the Kyoto Encyclopedia of Genes and Genomes Pathway (KEGG) database. Additionally, based on the transcriptome, we constructed a candidate cold tolerance gene set of C. heterophylla Fisch floral buds. The expression patterns of selected genes during four stages of cold acclimation suggested that these genes might be involved in different cold responsive stages in C. heterophylla Fisch floral buds. CONCLUSION: The transcriptome of C. heterophylla Fisch floral buds was deep sequenced, de novo assembled, and annotated, providing abundant data to better understand the C. heterophylla Fisch floral buds transcriptome. Candidate genes potentially involved in cold tolerance were identified, providing a material basis for future molecular mechanism analysis of C. heterophylla Fisch floral buds tolerant to cold stress.
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- 2014
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49. Heterogeneous effect of two selectin gene polymorphisms on coronary artery disease risk: a meta-analysis.
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Zhijun Wu, Yuqing Lou, Lin Lu, Yan Liu, Qiujing Chen, Xin Chen, and Wei Jin
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Medicine ,Science - Abstract
BACKGROUND: The selectins play important roles in the inflammatory process of coronary artery disease (CAD) and myocardial infarction (MI). Previous studies have shown ambiguous findings regarding a possible association between the selectin genes and CAD. The E-selectin Ser128Arg polymorphism and the P-selectin Thr715Pro polymorphism have been investigated widely but with inconsistent results. We performed a comprehensive meta-analysis to shed light on this issue. METHODS: Data were extracted by searches of MEDLINE, Embase, CNKI, Wanfang, Google Scholar, PORTA, GeNii, CiNii, J-STAGE, Nurimedia and Koreanstudies Information Service System [Kiss] up to October 2013, in which 10 studies on the Ser128Arg polymorphism with 3369 cases and 2577 controls and 10 studies on the Thr715Pro polymorphism with 5886 cases and 18345 controls. A random-effects model was used to calculate the combined odds ratios. The between-study heterogeneity and publication bias were addressed. RESULTS: The 128Arg carriers had a significant increased risk of CAD (allele comparison: P = 0.02, OR = 1.33, 95%CI 1.04-1.69, P(heterogeneity) = 0.01); The 715Pro conferred a non-significant risk reduction relative to the 715Thr (allele comparison: P = 0.40, OR = 0.94, 95%CI 0.82-1.08, P(heterogeneity) = 0.03).Subgroup analyses demonstrated that the 128Arg carriers had a significant increased risk of CAD among Asians (allele comparison: P = 0.001, OR = 2.07, 95%CI 1.33-3.24, P(heterogeneity) = 0.77) but not among Caucasians (allele comparison: P = 0.33, OR = 1.13, 95%CI 0.88-1.45, P(heterogeneity) = 0.08). Carrier status for the 715Pro was significantly associated with reduced risk of MI (allele comparison: P = 0.04, OR = 0.81, 95%CI 0.67-0.99, P(heterogeneity )= 0.14). The asymmetric funnel plot and the Egger's test (P = 0.041) suggested the presence of publication bias for the Ser128Arg polymorphism. CONCLUSION: Our results suggested there is an increase in the risk of CAD conferred by the Ser128Arg polymorphism and the thr715Pro polymorphism may be a protective factor of MI.
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- 2014
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50. Characterization and evolutionary implications of the triad Asp-Xxx-Glu in group II phosphopantetheinyl transferases.
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Yue-Yue Wang, Yu-Dong Li, Jian-Bo Liu, Xin-Xin Ran, Yuan-Yang Guo, Ni-Ni Ren, Xin Chen, Hui Jiang, and Yong-Quan Li
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Medicine ,Science - Abstract
Phosphopantetheinyl transferases (PPTases), which play an essential role in both primary and secondary metabolism, are magnesium binding enzymes. In this study, we characterized the magnesium binding residues of all known group II PPTases by biochemical and evolutionary analysis. Our results suggested that group II PPTases could be classified into two subgroups, two-magnesium-binding-residue-PPTases containing the triad Asp-Xxx-Glu and three-magnesium-binding-residue-PPTases containing the triad Asp-Glu-Glu. Mutations of two three-magnesium-binding-residue-PPTases and one two-magnesium-binding-residue-PPTase indicate that the first and the third residues in the triads are essential to activities; the second residues in the triads are non-essential. Although variations of the second residues in the triad Asp-Xxx-Glu exist throughout the whole phylogenetic tree, the second residues are conserved in animals, plants, algae, and most prokaryotes, respectively. Evolutionary analysis suggests that: the animal group II PPTases may originate from one common ancestor; the plant two-magnesium-binding-residue-PPTases may originate from one common ancestor; the plant three-magnesium-binding-residue-PPTases may derive from horizontal gene transfer from prokaryotes.
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- 2014
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