181 results on '"Shumei, Yang"'
Search Results
2. Sustained Evidence-Based Better Care Practice Implementation and Outcomes Among Very Preterm Infants: A Quality-Improvement Study in a Level 4 Neonatal Intensive Care Unit in Southern China
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Zhuxiao, Ren, Shumei, Yang, Qi, Zhang, and Fang, Xu
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- 2024
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3. An Experimental Study of the Acoustic Signal Characteristics of Locked-Segment Damage Evolution in a Landslide Model
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Xing Zhu, Hui Chen, Zhanglei Wu, Shumei Yang, Xiaopeng Li, and Tiantao Li
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three-section landslide ,locking section ,video image ,micro-seismic signal ,acoustic emission ,Chemical technology ,TP1-1185 - Abstract
Three-section landslides are renowned for their immense size, concealed development process, and devastating impact. This study conducted physical model tests to simulate one special geological structure called a three-section-within landslide. The failure process and precursory characteristics of the tested samples were meticulously analyzed using video imagery, micro-seismic (MS) signals, and acoustic emission (AE) signals, with a focus on event activity, intensity, and frequency. A novel classification method based on AE waveform characteristics was proposed, categorizing AE signals into burst signals and continuous signals. The findings reveal distinct differences in the evolution of these signals. Burst signals appeared exclusively during the crack propagation and failure stages. During these stages, the cumulative AE hits of burst signals increased gradually, with amplitude rising and then declining. High-amplitude burst signals were predominantly distributed in the middle- and high-frequency bands. In contrast, cumulative AE hits of continuous signals escalated rapidly, with amplitude monotonously increasing, and high-amplitude continuous signals were primarily distributed in the low-frequency band. The emergence of burst signals and high-frequency AE signals indicated the generation of microcracks, serving as early-warning indicators. Notably, the early-warning points of AE signals were detected earlier than those of video imagery and MS signals. Furthermore, the early-warning point of burst signals occurred earlier than those of continuous signals, and the early-warning point of the classification method preceded that of overall AE signals.
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- 2024
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4. Wnt5a-Flt1 activation contributes to preterm altered cerebral angiogenesis after prenatal inflammation
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Jiangxue, Han, Liling, Yang, Fang, Xu, Shumei, Yang, Gengying, Liu, Xuejun, Ren, Yao, Yao, Chuan, Nie, Jie, Yang, and Zhuxiao, Ren
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- 2023
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5. Prevention for moderate or severe BPD with intravenous infusion of autologous cord blood mononuclear cells in very preterm infants-a prospective non-randomized placebo-controlled trial and two-year follow up outcomes
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Zhuxiao, Ren, Fang, Xu, Wei, Wei, Shumei, Yang, Jianlan, Wang, Qiuping, Li, Jingjun, Pei, Chuan, Nie, Yongsheng, Li, Zhichun, Feng, and Jie, Yang
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- 2023
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6. Association between constipation and the development of asthma: a meta-analysis
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Lu Liu, Xiangli Zhang, Zhengdong Jiang, Guizuo Wang, Hua Wu, Ruilin Chen, Yongqing Zhang, Manxiang Li, and Shumei Yang
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Constipation ,Wheezing ,Asthma ,Meta-analysis ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Abstract Background Constipation has been hypothesized to be associated with the increased risk of wheezing or asthma. However, the relation remains a subject of debate. We conducted this meta-analysis to assess whether constipation influences the risk of wheezing/asthma. Methods PubMed, Embase, and Web of Science were systematically searched for studies published between 1955 and January 2022. Two reviewers independently extracted data and assessed the quality of each study. Results were pooled using fixed-effects models or random-effects models as appropriate. Results In total, 3 original articles with 178,661 participants, which met the criteria, were included in this meta-analysis. Constipation was associated with an increased risk of wheezing/asthma in later life (RR = 2.02, 95% CI = 1.24–3.29, P
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- 2022
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7. Factors affecting minimal manifestation status induction in myasthenia gravis
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Yi Li, Shumei Yang, Xiaohua Dong, Zhibin Li, Yuyao Peng, Wanlin Jin, Di Chen, Ran Zhou, Fei Jiang, Chengkai Yan, and Huan Yang
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Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Background: Minimal manifestation status (MMS) is an important landmark in the treatment of myasthenia gravis (MG), and predictors of MMS induction have rarely been identified in previous studies. Objective: The objective of this study is to evaluate the clinical factors associated with MMS induction among patients with MG. Design: This two-step retrospective cohort study with a single center investigated the factors that may be associated with MMS induction and retested these predictors in a test cohort. Methods: A total of 388 diagnosed MG patients who visited Xiangya Hospital between 1 July 2015 and 1 July 2019 were involved. We performed detailed chart reviews and recorded all cases achieving MMS. Demographics and clinical characteristics were also collected and their relationships to achieving MMS were investigated. Results: MMS was achieved in 124 patients (50.2%), and the median time to achieve MMS was 26 months. Several factors were found to be associated with MMS induction in exploring cohort, including muscle-specific tyrosine-protein kinase receptor (MuSK) antibody positivity (adjusted hazard ratio, HR = 4.333, 95% confidence interval, CI: 1.862–10.082), isolated ocular involvement (adjusted HR = 1.95, 95% CI: 1.284–2.961), and low baseline quantitative myasthenia gravis score (QMG score; adjusted HR = 2.022, 95% CI: 1.086–3.764). These factors were then retested in the test cohort. Isolated ocular involvement or low baseline QMG scores were factors found to be beneficial for MMS induction were confirmed. Conclusion: Isolated ocular involvement and low baseline QMG score are predictors of MMS induction in MG patients.
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- 2022
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8. Soluble glucocorticoid-induced tumor necrosis factor receptor regulates Helios expression in myasthenia gravis
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Yi Li, Shumei Yang, Zhibin Li, Huanyu Meng, Wanling Jin, Huan Yang, and Weifan Yin
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GITRL ,GITR ,Helios ,Myasthenia gravis ,Regulatory T cells ,Medicine - Abstract
Abstract Background Helios is important for functional and phenotype stability of regulatory T cells (Tregs). However, the role of Helios in autoimmune diseases and its regulation remains unclear. This study aimed to investigate the role of Helios+ Tregs in myasthenia gravis (MG) and glucocorticoid-induced tumor necrosis factor receptor (GITR) and its ligand (GITRL) in the modulation of Helios. Method Multicolor flow cytometry was performed to analyze Helios+ Tregs in peripheral blood from MG patients and healthy donors (HDs). Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of soluble GITRL/GITR in plasma. Tregs were isolated via magnetic separation and treated with recombinant GITRL and GITR-Fc. Membrane GITRL on Tregs and expression of Helios and other markers (FOXP3, CD25, CD39, CTLA-4, PD-L1 and IL-10) involved in immunosuppressive activity were determined by flow cytometry. Result Both Helios+ Tregs and soluble GITR were decreased in generalized MG (GMG) patients (n = 14), compared with HDs (n = 14) and ocular MG (OMG) patients (n = 16). Helios+ Tregs possessed greater immunosuppressive capacity compared to Helios− Tregs. Further analysis indicates soluble GITR was negatively correlated with quantitative MG score and promoted Helios expression and enhanced function of Tregs independently of membrane GITRL. Conclusion This work demonstrates abnormal changes in Helios+ Tregs and soluble GITR in MG, as well as direct regulation of Helios by GITR in the context of Tregs. This work provides new insight into the role of GITR in the regulatory pathway of Helios and pathogenesis of MG.
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- 2019
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9. Selection of Internal Standards for Quantitative Matrix-Assisted Laser Desorption/Ionization Mass Spectrometric Analysis Based on Correlation Coefficients
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Shumei Yang, Lei Mu, Ruxia Feng, and Xianglei Kong
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Chemistry ,QD1-999 - Published
- 2019
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10. Association between early bronchiolitis and the development of childhood asthma: a meta-analysis
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Manxiang Li, Lu Liu, Dong Han, Guizuo Wang, Zhengdong Jiang, and Shumei Yang
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Medicine - Abstract
Objective Early life bronchiolitis has been hypothesised to be associated with the subsequent risk of persistent wheezing or asthma. However, the link remains controversial. The objective of our study was to evaluate the association between bronchiolitis before 2 years of age and the late-onset wheezing/asthma.Design Systematic review and meta-analysis.Methods PubMed, Embase and Web of Science databases were systematically searched for studies published between 1955 and January 2020. Meanwhile, we also checked through the reference lists of relevant articles to see whether these references included reports of other studies that might be eligible for the review. Cohort and case–control studies assessing the association between early-life bronchiolitis and late-onset wheezing/asthma were included in this meta-analysis. Data were extracted by two independent reviewers. Results were pooled using a random-effects model or fixed-effects model according to the heterogeneity among studies.Results 32 original articles with 292 844 participants, which met the criteria, were included in this meta-analysis. Bronchiolitis before 2 years of age was associated with an increased risk of subsequent wheezing/asthma (relative risk=2.46, 95% CI 2.14 to 2.82, p
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- 2021
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11. Privacy-preserving k nearest neighbor query with authentication on road networks.
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Shumei Yang, Shaohua Tang, and Xiao Zhang
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- 2019
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12. IL-2 gene polymorphisms affect tacrolimus response in myasthenia gravis
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Shumei, Yang, Yi, Li, Huanyu, Meng, Zhibin, Li, Wanlin, Jin, Liqun, Xu, and Huan, Yang
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- 2019
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13. Human umbilical-cord mesenchymal stem cells inhibit bacterial growth and alleviate antibiotic resistance in neonatal imipenem-resistant infection
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Zhuxiao Ren, Xuaner Zheng, Haoming Yang, Qi Zhang, Xiaohong Liu, Xiaoling Zhang, Shumei Yang, Fang Xu, and Jie Yang
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Immunologic diseases. Allergy ,RC581-607 - Abstract
Human umbilical-cord mesenchymal stem cells (hUCMSCs) are a safe and convenient source of MSCs and have shown beneficial effects in neonatal infection and sepsis animal models. However, the factors leading to improved outcomes are still unclear. The aim of this study was to investigate the antibacterial effect and regulation of antimicrobial resistance of hUCMSCs. We separated imipenem-resistant Pseudomonas aeruginosa (PA) from neonates and incubated it with hUCMSCs as well as their culture medium. Assessment of direct inhibition of bacterial growth was done by counting CFUs. The concentration of antibacterial peptides in the culture medium of hUCMSCs was measured. Standard PA was inoculated with a sub-inhibitory concentration of imipenem with and without hUCMSC conditioned medium and antimicrobial peptides. The sensitivity to imipenem was detected until PA showed resistance to imipenem. Outer membrane protein (OprD2) mRNA expression in PA before and after the induction of imipenem resistance was analysed. We found that HUCMSCs possessed direct antimicrobial properties against bacteria and could alleviate antibiotic resistance via reserving OprD2 expression in PA.
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- 2020
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14. Fundamentals and Applications of Phosphorus Nanomaterials
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Hai-Feng (Frank) Ji, Yihang Liu, Dingzhou Cui, Mingrui Chen, Zhen Li, Chongwu Zhou, Pedro E. M. Amaral, Hai-Feng Ji, Yu Kyoung Ryu, Andres Castellanos-Gomez, Riccardo Frisenda, Ishaq Alalq, Jie Gao, Bin Wang, Xianglei Kong, Lei Mu, Ming Zhou, Shumei Yang, Michael Shatruk, Bowei Dong, Li Huang, Cheng
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- 2019
15. Binding Properties of Odorant-Binding Protein 4 of Tirathaba rufivena to Areca catechu Volatiles
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Xiang Zhou, Zheng Wang, Guangchao Cui, Zimeng Du, Yunlong Qian, Shumei Yang, Minghui Liu, and Jixing Guo
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odorant-binding proteins ,Tirathaba rufivena ,binding ability ,fluorescence competitive binding assays ,molecular docking ,Botany ,QK1-989 - Abstract
Odorant-binding proteins (OBPs) play a key role in the olfactory system and are essential for mating and oviposition host selection. Tirathaba rufivena, a serious lepidopterous insect pest of the palm area in recent years, has threatened cultivations of Areca catechu in Hainan. Female-biased odorant-binding protein 4 of T. rufivena (TrufOBP4) expression was hypothesized to participate in the process of oviposition host recognition and localization. In this study, we cloned and analyzed the cDNA sequence of TrufOBP4. The predicted mature protein TrufOBP4 is a small, soluble, secretory protein and belongs to a classic OBP subfamily. Fluorescence binding assay results showed that TrufOBP4 had high binding abilities with the host plant volatiles, octyl methoxycinnamate, dibutyl phthalate, myristic acid and palmitic acid. These four components tend to dock in the same binding pocket based on the molecular docking result. The interactions and contributions of key amino acid residues were also characterized. This research provides evidence that TrufOBP4 might participate in the chemoreception of volatile compounds from inflorescences of A. catechu and can contribute to the integrated management of T. rufivena.
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- 2022
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16. Human Umbilical Cord Mesenchymal Stem Cells Prevent Bacterial Biofilm Formation
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Haoming Yang, Fang Xu, Xuaner Zheng, Shumei Yang, Zhuxiao Ren, and Jie Yang
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Article Subject ,General Immunology and Microbiology ,Biofilms ,Infant, Newborn ,Humans ,Mesenchymal Stem Cells ,General Medicine ,Infant, Premature ,General Biochemistry, Genetics and Molecular Biology ,Anti-Bacterial Agents ,Umbilical Cord - Abstract
Biofilm formation is easily found in patients suffered from ventilator-associated pneumonia (VAP) in neonatal intensive care unit (NICU) and makes the VAP infections not only harder to be treated but easier to relapse. In order to find some novel ways to inhibit biofilm formation, this study describe a previously unrecognized role for the human umbilical cord mesenchymal stem cells (hUCMSCs). In addition to multiple differentiation, hUCMSCs have the ability to prevent the biofilms formation in vitro by secreting antibacterial peptides (LL-37 and hBD-2). This occurred while P. aeruginosa PA27853 and hUCMSCs were cocultured, and the filtrated medium, which was the supernatant containing antibacterial peptides (5.9 ng/ml of LL-37, 1.77 ng/ml of hBD-2), and inhibited the growth of the bacterial biofilm on the surface of tracheal tube (2.5#, for preterm infant). Using microarrays, we were able to demonstrate that the antibacterial peptides from hUCMSC affected biofilm formation by downregulating the gene-encoded polysaccharide biosynthesis protein. In addition, in order to find out the most suitable concentration of hUCMSCs, P. aeruginosa was cocultured with eight-level concentrations of hUCMSCs, and we found that the concentration of LL-37 was positively correlated with the concentration of hUCMSCs. Meanwhile, the concentration of LL-37 became stable while the hUCMSC concentration reaches higher than 5 × 10 6 cells / ml . But the concentration of hBD-2 had no significant correlation with hUCMSCs. The collection of these stem cells is not only limited by ethics but also reduces host rejection. This makes it possible to use autologous hUCMSCs to treat neonatal VAP.
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- 2022
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17. Reduction of antibiotic use and multi-drug resistance bacteria infection in neonates after improvement of antibiotics use strategy in a level 4 neonatal intensive care unit in southern China
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Zhuxiao Ren, Shumei Yang, Jiangxue Han, Chuan Nie, Cuicui Wang, Jianlan Wang, Xuaner Zheng, Haoming Yang, Qi Zhang, Jingjun Pei, Fang Xu, and Jie Yang
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Microbiology (medical) ,Infectious Diseases ,General Medicine - Abstract
The investigation on antibiotic stewardship in neonatal intensive care unit in China is scarce. This study aimed to analyze the effect of a comprehensive 2-year antibiotic stewardship in a level 4 NICU. During this baseline period from October 1st 2017 to October 1st 2019, continuation of empirical antibiotic therapy for ruled-out sepsis courses was beyond 72 h and for pneumonia was more than 7 days. Meropenem or vancomycin was used even if they were not the only bacterial sensitive antibiotics. The intervention period was from October 2nd 2019 to August 23rd 2021. Three areas for quality improvement were targeted in our center: discontinuation of antibiotic use in ruled-out sepsis within 72 h, treatment duration for culture-negative pneumonia less than 7 days, and vancomycin or meropenem was not used unless the cultured bacteria was only susceptible to them. The total antibiotic consumption decreased from 791.1 to 466.3 days of therapy per 1000 patient days from baseline to intervention period. Antibiotics were stopped within 72 h for 47.48% patients with rule-out sepsis and within 7 days for 75.70% patients with pneumonia compared with 11.56% and 37.69% during the baseline period respectively. The prevalence of multi-drug resistance bacteria decreased from 67.20 to 48.90%. The total use rate of meropenem or vancomycin decreased from 7.6 to 1.8%. Our quality improvement approach on antibiotic strategy significantly reduced antibiotic use and prevalence of multi-drug resistance bacteria in our NICU.
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- 2022
18. Research on the Distribution of Attention in the Course of Maintenance Training.
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Wei Liu and Shumei Yang
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- 2014
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19. LXA4 inhibits TGF-β1-induced airway smooth muscle cells proliferation and migration by suppressing the Smad/YAP pathway
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Yali Zhao, Xiangli Zhang, Guizuo Wang, Hua Wu, Ruilin Chen, Yongqing Zhang, Shumei Yang, and Lu Liu
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Pharmacology ,Immunology ,Immunology and Allergy - Published
- 2023
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20. A prediction model based on routine blood indicators for the early diagnosis of serious bacterial infection in infants: a case-control study (Preprint)
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Runqiang Liang, Ziyu Chen, Shumei Yang, Zhu Wang, Xin Lin, and Fang Xu
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BACKGROUND Routine blood test is an easily accessible, more economical, quick and routine method to examine infectious-related diseases. The prediction effect of routine blood parameters has rarely reported in the diagnosis of serious bacterial infections (SBI). OBJECTIVE This study aims to develop a model for early diagnosis of SBI using routine blood parameters. METHODS This case-control study was conducted based on the data collected from the Medical Information Mart for Intensive Care III (MIMIC-III) included children under one year. SBI was defined as urinary tract infections, meningitis, and sepsis. Lasso regression was used to screen the potential determiners. The model was developed with random forest analysis based on routine blood parameters, and performance was assessed through calculating the area under the curve (AUC). Propensity score-matching (PSM) method was used to eliminate the impact of ethnicity-related bias. RESULTS After PSM, a total of 1,160 participants were included, with 232 in SBI group and 928 in non-SBI group. Red blood cell distribution width (RDW), hemoglobin (HGB), neutrophil, platelets (PLT) counts, monocyte, white blood cell (WBC) counts, mean corpuscular volume (MCV), neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and systemic immune-inflammation index (SII) were screened out to develop the model, with AUC of 0.824 [95% confidence interval (CI): 0.789-0.859]. The variable importance of random forest demonstrated that WBC, MCV, SII and other top-ranked variables were shown as significant factors for the diagnosis of SBI. CONCLUSIONS Our model based on routine blood parameters showed a good performance, indicating the availability of this model in the clinic.
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- 2022
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21. Promoter methylation represses AT2R gene and increases brain hypoxic–ischemic injury in neonatal rats
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Yong Li, Daliao Xiao, Shumei Yang, and Lubo Zhang
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Nicotine ,AT2R ,Methylation ,Hypoxic–ischemic encephalopathy ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Perinatal nicotine exposure downregulated angiotensin II type 2 receptor (AT2R) in the developing brain and increased brain vulnerability to hypoxic–ischemic injury in male neonatal rats. We tested the hypothesis that site-specific CpG methylation at AT2R gene promoter contributes to the increased vulnerability of brain injury in the neonate. Nicotine was administered to pregnant rats from day 4 of gestation to day 10 after birth. Brain hypoxic–ischemic injury was induced in day 10 male pups. CpG methylation at AT2R promoter was determined in the brain by quantitative methylation-specific PCR. Nicotine exposure significantly increased the methylation of a single CpG−52 locus near the TATA-box at AT2R promoter. Electrophoretic mobility shift assay indicated that the methylation of CpG−52 significantly decreased the binding affinity of TATA-binding protein (TBP). Chromatin immunoprecipitation assay further demonstrated an increase in the binding of a methyl-binding protein and a decrease in TBP binding to AT2R promoter in vivo in neonatal brains of nicotine-treated animals. This resulted in AT2R gene repression in the brain. Intracerebroventricular administration of a demethylating agent 5-aza-2′-deoxycytidine abrogated the enhanced methylation of CpG−52, rescued the TBP binding, and restored AT2R gene expression. Of importance, 5-aza-2′-deoxycytidine reversed the nicotine-increased vulnerability of brain hypoxic–ischemic injury in the neonate. The finding provides mechanistic evidence of increased promoter methylation and resultant AT2R gene repression in the developing brain linking perinatal stress and a pathophysiological consequence of heightened vulnerability of brain hypoxic–ischemic encephalopathy in the neonate.
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- 2013
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22. Placental pathology and neonatal outcomes in pre-eclampsia with gestational diabetes mellitus
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Fang Xu, Shumei Yang, Jiangyu Zhang, Haoming Yang, Xuaner Zheng, Zhuxiao Ren, Ying Liu, and Jie Yang
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0301 basic medicine ,medicine.medical_specialty ,endocrine system diseases ,Placenta ,03 medical and health sciences ,0302 clinical medicine ,Pre-Eclampsia ,Pregnancy ,Placental pathology ,medicine ,Humans ,reproductive and urinary physiology ,Retrospective Studies ,030219 obstetrics & reproductive medicine ,Eclampsia ,business.industry ,Obstetrics ,Infant, Newborn ,Pregnancy Outcome ,nutritional and metabolic diseases ,Obstetrics and Gynecology ,Retrospective cohort study ,medicine.disease ,humanities ,female genital diseases and pregnancy complications ,Gestational diabetes ,Diabetes, Gestational ,030104 developmental biology ,Neonatal outcomes ,Pediatrics, Perinatology and Child Health ,Female ,business - Abstract
To investigate histopathological placental lesions and adverse neonatal outcomes by Pre-eclampsia (PE) with Gestational Diabetes Mellitus (GDM).This was a retrospective cohort study of pregnancies with PE delivered between 1 January 2012 to 1 January 2014. Pregnant women with PE were recruited, and divided into PE with GDM (PE + GDM) group (The (PE + GDM) group was significantly associated with high placenta weight (534.8 ± 124.1 vs 519.3 ± 132.3 g,GDM increased the offspring's complication in pregnancy with PE, the potential mechanism might be that GDM increased the placenta inflammation.
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- 2020
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23. Detection of Microbiota from Human Thymus of Myasthenia Gravis
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Huanyu Meng, Zhaohui Luo, Liqun Xu, Huan Yang, Yi Li, Zhibin Li, Wanlin Jin, and Shumei Yang
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Autoimmune disease ,Klebsiella ,biology ,business.industry ,medicine.medical_treatment ,Ribosomal RNA ,medicine.disease ,biology.organism_classification ,medicine.disease_cause ,Myasthenia gravis ,Microbiology ,Thymectomy ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,030220 oncology & carcinogenesis ,medicine ,biology.protein ,030211 gastroenterology & hepatology ,Surgery ,Antibody ,business ,Escherichia coli - Abstract
Myasthenia gravis (MG) is an autoimmune disease caused by antibodies directed against different components of the neuromuscular junction (NMJ), and pathogenic mechanism associated thymic pathologies. Microbiota invading thymus is hypothesized to trigger human autoimmune response by providing antigens to produce NMJ antibodies and clinical manifestations of myasthenia gravis. There are many reports of microbial nucleic acid isolation and protein expression and even a few studies of viable microbes isolated from the human thymus. However, high-resolution investigation of microbial infectious agents from the human thymus that may contribute to myasthenia gravis is very limited. To investigate potential microbial infection within human thymus tissue samples, we performed quantitative real-time PCR of the bacterial 16S ribosomal RNA (rRNA) and fungal 18S rRNA gene analysis on (1) a total of 23 abnormal thymus including 13 thymomas and 4 thymus hyperplasias obtained from MG patients and 6 thymoma-nonMG patients who underwent thymectomy. (2) Another 14 normal thymus were selected as control from patients who underwent congenital heart disease surgery. Results show that a wide range of bacteria agents are exhibited in the thymus, rather than fungus. And an intriguing new observation that shows the microbiota displayed differences among MG patients, thymoma-nonMG patients, and normal thymus as judged from the taxonomic profiles in these three groups. Compared with the normal thymus group, the Klebsiella and Escherichia coli show higher abundance in MG patient group. The thymus harbors bacteria agents and Klebsiella and Escherichia coli may be potential pathogens associated with MG. Further investigations are needed to elucidate the possible associations of Klebsiella and E. coli and MG.
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- 2020
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24. Binding Properties of Odorant-Binding Protein 4 of
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Xiang, Zhou, Zheng, Wang, Guangchao, Cui, Zimeng, Du, Yunlong, Qian, Shumei, Yang, Minghui, Liu, and Jixing, Guo
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binding ability ,fluorescence competitive binding assays ,Tirathaba rufivena ,odorant-binding proteins ,molecular docking ,Article - Abstract
Odorant-binding proteins (OBPs) play a key role in the olfactory system and are essential for mating and oviposition host selection. Tirathaba rufivena, a serious lepidopterous insect pest of the palm area in recent years, has threatened cultivations of Areca catechu in Hainan. Female-biased odorant-binding protein 4 of T. rufivena (TrufOBP4) expression was hypothesized to participate in the process of oviposition host recognition and localization. In this study, we cloned and analyzed the cDNA sequence of TrufOBP4. The predicted mature protein TrufOBP4 is a small, soluble, secretory protein and belongs to a classic OBP subfamily. Fluorescence binding assay results showed that TrufOBP4 had high binding abilities with the host plant volatiles, octyl methoxycinnamate, dibutyl phthalate, myristic acid and palmitic acid. These four components tend to dock in the same binding pocket based on the molecular docking result. The interactions and contributions of key amino acid residues were also characterized. This research provides evidence that TrufOBP4 might participate in the chemoreception of volatile compounds from inflorescences of A. catechu and can contribute to the integrated management of T. rufivena.
- Published
- 2021
25. Association between early bronchiolitis and the development of childhood asthma: a meta-analysis
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Zhengdong Jiang, Lu Liu, Guizuo Wang, Shumei Yang, Manxiang Li, and Dong Han
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Pediatrics ,medicine.medical_specialty ,Allergy ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,medicine ,Humans ,respiratory medicine (see thoracic medicine) ,030212 general & internal medicine ,Prospective Studies ,Prospective cohort study ,Respiratory Medicine ,Asthma ,Respiratory Sounds ,business.industry ,Confounding ,General Medicine ,asthma ,medicine.disease ,allergy ,030228 respiratory system ,Bronchiolitis ,Meta-analysis ,Relative risk ,Cohort ,Medicine ,business - Abstract
ObjectiveEarly life bronchiolitis has been hypothesised to be associated with the subsequent risk of persistent wheezing or asthma. However, the link remains controversial. The objective of our study was to evaluate the association between bronchiolitis before 2 years of age and the late-onset wheezing/asthma.DesignSystematic review and meta-analysis.MethodsPubMed, Embase and Web of Science databases were systematically searched for studies published between 1955 and January 2020. Meanwhile, we also checked through the reference lists of relevant articles to see whether these references included reports of other studies that might be eligible for the review. Cohort and case–control studies assessing the association between early-life bronchiolitis and late-onset wheezing/asthma were included in this meta-analysis. Data were extracted by two independent reviewers. Results were pooled using a random-effects model or fixed-effects model according to the heterogeneity among studies.Results32 original articles with 292 844 participants, which met the criteria, were included in this meta-analysis. Bronchiolitis before 2 years of age was associated with an increased risk of subsequent wheezing/asthma (relative risk=2.46, 95% CI 2.14 to 2.82, pConclusionsThe meta-analysis indicates an association between bronchiolitis before 2 years of age and the wheezing/asthma in later life. Well-designed and highly standardised prospective studies that better address bias due to potential confounding factors are needed to validate the risk identified in our meta-analysis.PROSPERO registration numberCRD42018089453.
- Published
- 2021
26. Factors affecting minimal manifestation status induction in myasthenia gravis
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Yi Li, Shumei Yang, Xiaohua Dong, Zhibin Li, Yuyao Peng, Wanlin Jin, Di Chen, Ran Zhou, Fei Jiang, Chengkai Yan, and Huan Yang
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Pharmacology ,Neurology ,Neurology (clinical) - Abstract
Background: Minimal manifestation status (MMS) is an important landmark in the treatment of myasthenia gravis (MG), and predictors of MMS induction have rarely been identified in previous studies. Objective: The objective of this study is to evaluate the clinical factors associated with MMS induction among patients with MG. Design: This two-step retrospective cohort study with a single center investigated the factors that may be associated with MMS induction and retested these predictors in a test cohort. Methods: A total of 388 diagnosed MG patients who visited Xiangya Hospital between 1 July 2015 and 1 July 2019 were involved. We performed detailed chart reviews and recorded all cases achieving MMS. Demographics and clinical characteristics were also collected and their relationships to achieving MMS were investigated. Results: MMS was achieved in 124 patients (50.2%), and the median time to achieve MMS was 26 months. Several factors were found to be associated with MMS induction in exploring cohort, including muscle-specific tyrosine-protein kinase receptor (MuSK) antibody positivity (adjusted hazard ratio, HR = 4.333, 95% confidence interval, CI: 1.862–10.082), isolated ocular involvement (adjusted HR = 1.95, 95% CI: 1.284–2.961), and low baseline quantitative myasthenia gravis score (QMG score; adjusted HR = 2.022, 95% CI: 1.086–3.764). These factors were then retested in the test cohort. Isolated ocular involvement or low baseline QMG scores were factors found to be beneficial for MMS induction were confirmed. Conclusion: Isolated ocular involvement and low baseline QMG score are predictors of MMS induction in MG patients.
- Published
- 2021
27. miR-152/TNS1 axis inhibits non-small cell lung cancer progression through Akt/mTOR/RhoA pathway
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Yi Miao, Li Wang, Li-qun Shang, Hua Wu, Jinjin Duan, Shumei Yang, and Yongcheng Huang
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RHOA ,Lung Neoplasms ,growth ,Cell ,Biophysics ,NSCLC ,Biochemistry ,Metastasis ,miR-152 ,Akt/mTOR/RhoA pathway ,Carcinoma, Non-Small-Cell Lung ,Cell Line, Tumor ,Tensins ,medicine ,Tensin ,metastasis ,Humans ,Lung cancer ,Molecular Biology ,Protein kinase B ,neoplasms ,PI3K/AKT/mTOR pathway ,Research Articles ,Cancer ,biology ,Cell growth ,business.industry ,TOR Serine-Threonine Kinases ,Cell Biology ,medicine.disease ,respiratory tract diseases ,MicroRNAs ,medicine.anatomical_structure ,Cancer research ,biology.protein ,TNS1 ,business ,rhoA GTP-Binding Protein ,Proto-Oncogene Proteins c-akt - Abstract
Aim: The purpose of the present study was to explore the function and mechanism of tensin 1 (TNS1) in non-small cell lung cancer (NSCLC) progression. Methods: The expression of TNS1 in NSCLC cells and tissues was assessed by RT-PCR and Western blot. Besides, Kaplan–Meier survival analysis was recruited to explore the association between TNS1 and NSCLC. Cell growth was analyzed by MTT and flow cytometry assay, while cell metastasis was determined by wound healing and transwell assays. The targeting relationship between TNS1 and miR-152 was assessed by luciferase activity assays. And Western blot was employed to determine the expression of related proteins of Akt/mTOR/RhoA pathway. Results: TNS1 level was boosted in NSCLC cells and tissues, related to the prognosis of NSCLC patients. Furthermore, it was proved that TNS1 promoted the growth and metastasis of NSCLC cells via Akt/mTOR/RhoA pathway. And miR-152 targeted TNS1 to affect the progression of NSCLC. Conclusion: miR-152/TNS1 axis inhibits the progression of NSCLC by Akt/mTOR/RhoA pathway.
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- 2021
28. Chronic hypoxia during gestation enhances uterine arterial myogenic tone via heightened oxidative stress.
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Daliao Xiao, Xiang-Qun Hu, Xiaohui Huang, Jianjun Zhou, Sean M Wilson, Shumei Yang, and Lubo Zhang
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Medicine ,Science - Abstract
Chronic hypoxia during gestation has profound adverse effects on the adaptation of uteroplacental circulation in pregnancy. Yet, the underlying mechanisms are not fully understood. The present study tested the hypothesis that enhanced production of reactive oxygen species (ROS) in uterine arteries plays a critical role in the maladaptation of uterine circulation associated with chronic hypoxia. Uterine arteries were isolated from nonpregnant and near-term pregnant sheep maintained at sea level (~300 m) or exposed to high-altitude (3801 m) hypoxia for 110 days. Hypoxia significantly increased ROS production in uterine arteries of pregnant, but not nonpregnant, sheep. This was associated with a significant increase in NADPH oxidase (Nox) 2, but not Nox1 or Nox4, protein abundance and total Nox activity in uterine arteries of pregnant animals. Chronic hypoxia significantly increased pressure-dependent uterine arterial myogenic tone in pregnant sheep, which was abrogated by a Nox inhibitor apocynin. Additionally, the hypoxia-induced increase in myogenic reactivity of uterine arteries to phorbol 12,13-dibutyrate in pregnant sheep was blocked by apocynin and tempol. In consistence with the myogenic responses, the hypoxia-mediated down-regulation of BKCa channel activity in uterine arteries of pregnant animals was reversed by apocynin. The findings suggest that heightened oxidative stress in uterine arteries plays a key role in suppressing the BKCa channel activity, resulting in increased myogenic reactivity and maladaptation of uteroplacental circulation caused by chronic hypoxia during gestation.
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- 2013
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29. STIM1 mediates IAV-induced inflammation of lung epithelial cells by regulating NLRP3 and inflammasome activation via targeting miR-223
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Li-qun Shang, Rui-lin Chen, Shumei Yang, Hua Wu, Yi Miao, Yongqing Zhang, and Cuicui Liu
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inorganic chemicals ,0301 basic medicine ,Adult ,Male ,Programmed cell death ,Cell Survival ,Inflammasomes ,medicine.medical_treatment ,Inflammation ,Apoptosis ,Lung injury ,030226 pharmacology & pharmacy ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Influenza, Human ,NLR Family, Pyrin Domain-Containing 3 Protein ,medicine ,Humans ,Viability assay ,Stromal Interaction Molecule 1 ,General Pharmacology, Toxicology and Pharmaceutics ,Lung ,Chemistry ,Inflammasome ,Epithelial Cells ,General Medicine ,Prognosis ,Neoplasm Proteins ,MicroRNAs ,030104 developmental biology ,Cytokine ,Influenza A virus ,Case-Control Studies ,Cancer research ,Cytokines ,Female ,medicine.symptom ,medicine.drug - Abstract
Aims Influenza A virus (IAV) infection accelerates the inflammatory injury of lung epithelial cells that contributes to pulmonary lesion. Recently, stromal interaction molecule 1 (STIM1) was found to mediate cellular immune response and participated in lung tumorigenesis. Our study aimed to illustrate the function and mechanism of STIM1 in IAV-induced inflammation injury and oxidative stress of lung epithelial cells. Main methods We evaluated the levels of STIM1 in IAV-infected patients' serum and BEAS-2B cells using RT-qPCR, Elisa and western blotting methods. MTT and Elisa were performed to measure cell viability and cytokine contents. Besides, ROS intensity, SOD contents and cell apoptosis were detected based on DCFH-DA probe, colorimetry and cell death kits. A luciferase assay and Pearson's correlation analysis evaluated the associations between target genes. Key findings STIM1 was dramatically up-regulated in IAV-infected patients' serum and BEAS-2B cells. Silencing STIM1 in vitro inhibited oxidative stress and inflammatory responses induced by IAV, and reversed cell viability and suppressed apoptosis. Moreover, miR-223 and NLRP3 were negatively and positively correlated with STIM1. STIM1 was found to regulate NLRP3 expression by binding the AACUGAC motif in miR-223. STIM1/miR-223/NLRP3 axis modulated IAV-induced inflammation injury of lung epithelial cells. Significance Our evidence indicated that silencing STIM1 alleviated IAV-induced inflammation injury of lung epithelial cells by inactivating NLRP3 and inflammasome via promoting miR-223 expression. These findings may contribute to understand the mechanism of IAV-induced lung injury and help for therapy of IAV infection.
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- 2020
30. Competition between metal cationization and protonation/reduction in MALDI process: An example of riboflavin
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Yuan Ma, Xianglei Kong, Yingying Shi, Shumei Yang, and Lei Mu
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Covariance mapping ,Chemistry ,010401 analytical chemistry ,Protonation ,010402 general chemistry ,Condensed Matter Physics ,Alkali metal ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,Ion ,Metal ,Matrix (chemical analysis) ,visual_art ,Mass spectrum ,visual_art.visual_art_medium ,Molecule ,Physical and Theoretical Chemistry ,Instrumentation ,Spectroscopy - Abstract
In order to better understand effects of metal cationization on protonation and reduction in MALDI process, mass spectra of riboflavin complexes with different alkali metal ions generated by a series of laser shots at a fixed target spot were consecutively recorded with the matrix of 2,5-dihydroxybenzoic acid (DHB). Progressive changes in the spectra, including the decrease of reduction extent for the metalized molecule ions and the increase of relative intensities of metalized species compared to protonated species, were observed with the increase of laser shots. Covariance mapping analysis was also performed for the data. Results show that different metalized ions are positively correlated each other; while metalized ions and protonated species are negatively correlated. These results not only reflect competition between metalization and protonation/reduction in laser plume, but also show that the winner of it might be changed during the process of sample consumption by laser irradiation.
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- 2018
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31. Long-term high altitude hypoxia during gestation suppresses large conductance Ca2+ -activated K+ channel function in uterine arteries: a causal role for microRNA-210
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Shumei Yang, Jeffery Xiao, Lubo Zhang, Xiang-Qun Hu, and Chiranjib Dasgupta
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0301 basic medicine ,medicine.medical_specialty ,Fetus ,Physiology ,Chemistry ,Intrauterine growth restriction ,Endogeny ,030204 cardiovascular system & hematology ,Hypoxia (medical) ,medicine.disease ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Endocrinology ,Downregulation and upregulation ,Internal medicine ,Uteroplacental Circulation ,medicine ,medicine.symptom ,Psychological repression ,Hormone - Abstract
Key points Gestational hypoxia represses ten-eleven translocation methylcytosine dioxygenase 1 (TET1) expression in uterine arteries, which is recovered by inhibiting endogenous miR-210. Inhibition of miR-210 rescues BKCa channel expression and current in uterine arteries of pregnant animals acclimatized to high altitude hypoxia in a TET-dependent manner. miR-210 blockade restores BKCa channel-mediated relaxations and attenuates pressure-dependent myogenic tone in uterine arteries of pregnant animals acclimatized to high altitude. Abstract Gestational hypoxia at high altitude has profound adverse effects on the uteroplacental circulation, and is associated with increased incidence of preeclampsia and fetal intrauterine growth restriction. Previous studies demonstrated that suppression of large-conductance Ca2+ -activated K+ (BKCa ) channel function played a critical role in the maladaptation of uteroplacental circulation caused by gestational hypoxia. Yet, the mechanisms underlying gestational hypoxia-induced BKCa channel repression remain undetermined. The present study investigated a causal role of microRNA-210 (miR-210) in hypoxia-mediated repression of BKCa channel expression and function in uterine arteries using a sheep model. The results revealed that gestational hypoxia significantly decreased ten-eleven translocation methylcytosine dioxygenase 1 (TET1) expression in uterine arteries, which was recovered by inhibiting endogenous miR-210 with miR-210 locked nucleic acid (miR-210-LNA). Of importance, miR-210-LNA restored BKCa channel β1 subunit expression in uterine arteries, which was blocked by a competitive TET inhibitor, fumarate, thus functionally linking miR-210 to the TET1-BKCa channel cascade. In addition, miR-210-LNA reversed hypoxia-mediated suppression of BKCa channel function and rescued the effect of steroid hormones in upregulating BKCa channel expression and function in uterine arteries, which were also ablated by fumarate. Collectively, the present study demonstrates a causative effect of miR-210 in the downregulation of TET1 and subsequent repression of BKCa channel expression and function, providing a novel mechanistic insight into the regulation of BKCa channel function and the molecular basis underlying the maladaptation of uterine vascular function in gestational hypoxia.
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- 2018
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32. SIRT1 increases cardiomyocyte binucleation in the heart development
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Alexandra N. Shin, Limin Han, Lubo Zhang, Chiranjib Dasgupta, Lei Huang, and Shumei Yang
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0301 basic medicine ,Cardiac function curve ,Senescence ,Cell ,Retinoic acid ,cardiomyocyte ,Biology ,miR-133a ,03 medical and health sciences ,chemistry.chemical_compound ,SIRT1 ,Downregulation and upregulation ,Gene expression ,medicine ,binucleation ,030102 biochemistry & molecular biology ,Heart development ,hypoxia ,Hypoxia (medical) ,Cell biology ,enzymes and coenzymes (carbohydrates) ,030104 developmental biology ,medicine.anatomical_structure ,Oncology ,chemistry ,medicine.symptom ,hormones, hormone substitutes, and hormone antagonists ,Research Paper - Abstract
SIRT1 regulates cell senescence. We investigated a novel role of SIRT1 in the regulation of cardiomyocyte terminal differentiation in the developing heart. Retinoic acid (RA)-induced binucleation of H9c2 cells was associated with increased SIRT1 expression. Inhibition of SIRT1 activity or expression significantly decreased RA-induced binucleation. SIRT1 expression was minimal in the fetal heart and significantly upregulated in the hearts of postnatal day 7 (P7) rat pups. In contrast, heart-specific miR-133a expression was high in the fetal heart but significantly reduced in P7 pup hearts. The miR-133a promoter contains a canonical HRE element and hypoxia upregulated miR-133a gene expression in the heart. SIRT1 mRNA 3'UTR has miR-133a binding sequences and miR-133a and hypoxia suppressed SIRT1 expression in cardiomyocytes. Of importance, inhibition of SIRT1 significantly reduced binucleated cardiomyocytes in the hearts of P7 pups. Taken together, the present study reveals a novel role of SIRT1 and its regulation by miR-133a in cardiomyocyte terminal differentiation of the developing heart, and suggests a potential therapeutic strategy that may impact cardiac function later in life.
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- 2018
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33. MicroRNA-210 Targets Ten-Eleven Translocation Methylcytosine Dioxygenase 1 and Suppresses Pregnancy-Mediated Adaptation of Large Conductance Ca 2+ -Activated K + Channel Expression and Function in Ovine Uterine Arteries
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Daliao Xiao, Chiranjib Dasgupta, Xiang-Qun Hu, Lubo Zhang, Shumei Yang, and Xiaohui Huang
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0301 basic medicine ,medicine.medical_specialty ,Messenger RNA ,Endogeny ,Chromosomal translocation ,Biology ,Hypoxia (medical) ,medicine.disease ,Preeclampsia ,03 medical and health sciences ,030104 developmental biology ,Endocrinology ,Downregulation and upregulation ,Internal medicine ,medicine.artery ,Internal Medicine ,medicine ,Myocyte ,medicine.symptom ,Uterine artery - Abstract
Gestational hypoxia inhibits large conductance Ca 2+ -activated K + (BK Ca ) channel expression and function in uterine arterial adaptation to pregnancy. Given the findings that microRNA-210 (miR-210) is increased in hypoxia during gestation and preeclampsia, the present study sought to investigate the role of miR-210 in the regulation of BK Ca channel adaptation in the uterine artery. Gestational hypoxia significantly increased uterine vascular resistance and blood pressure in pregnant sheep and upregulated miR-210 in uterine arteries. MiR-210 bound to ovine ten-eleven translocation methylcytosine dioxygenase 1 mRNA 3′ untranslated region and decreased ten-eleven translocation methylcytosine dioxygenase 1 mRNA and protein abundance in uterine arteries of pregnant sheep, as well as abrogated steroid hormone–induced upregulation of ten-eleven translocation methylcytosine dioxygenase 1 expression in uterine arteries of nonpregnant animals. In accordance, miR-210 blocked pregnancy- and steroid hormone–induced upregulation of BK Ca channel β1 subunit expression in uterine arteries. Functionally, miR-210 suppressed BK Ca channel current density in uterine arterial myocytes of pregnant sheep and inhibited steroid hormone–induced increases in BK Ca channel currents in uterine arteries of nonpregnant animals. Blockade of endogenous miR-210 inhibited hypoxia-induced suppression of BK Ca channel activity. In addition, miR-210 decreased BK Ca channel–mediated relaxations and increased pressure-dependent myogenic tone of uterine arteries. Together, the results demonstrate that miR-210 plays an important role in the downregulation of ten-eleven translocation methylcytosine dioxygenase 1 and repression of BK Ca channel function in uterine arteries, revealing a novel mechanism of epigenetic regulation in the maladaptation of uterine hemodynamics in gestational hypoxia and preeclampsia.
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- 2017
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34. IRMPD spectroscopy of metal cationized ions generated by MALDI source with graphene as the matrix
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Lei Mu, Shumei Yang, Xianglei Kong, and Ruxia Feng
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Chemistry ,Graphene ,010401 analytical chemistry ,Analytical chemistry ,Chromophore ,010402 general chemistry ,Condensed Matter Physics ,01 natural sciences ,Spectral line ,0104 chemical sciences ,law.invention ,Ion ,Matrix (chemical analysis) ,Metal ,law ,visual_art ,visual_art.visual_art_medium ,Infrared multiphoton dissociation ,Physical and Theoretical Chemistry ,Spectroscopy ,Instrumentation - Abstract
A new strategy to obtain IRMPD spectra of metal cationized ions by combining MALDI and IRMPD methods is presented here, in which graphene is selected to be the matrix to generate the metal cationized ions. [Arg + Rb]+ were studied here as the sample ions. Based on the experiential IRMPD spectrum and theoretical calculations, it is suggested that the ions of [Arg + Rb]+ generated here had more internal energies than those generated by ESI method reported previously by Williams et al. (J. Phys. Chem. A 2007, 111, 11759–11770). The method is also combined with the H/D exchange to identify the chromophores for the observed IR peak. The method provides a new way to obtain structural information of metal cationized ions, and also makes the identification of isomeric compounds feasible.
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- 2017
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35. Pregnancy Reprograms Large-Conductance Ca 2+ -Activated K + Channel in Uterine Arteries
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Xiaohui Huang, Shumei Yang, Limin Han, Man Chen, Zhice Xu, Lubo Zhang, Daliao Xiao, Xiang-Qun Hu, and Chiranjib Dasgupta
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0301 basic medicine ,Hormone response element ,medicine.medical_specialty ,medicine.drug_class ,medicine.medical_treatment ,Vasodilation ,030204 cardiovascular system & hematology ,Biology ,03 medical and health sciences ,Steroid hormone ,030104 developmental biology ,0302 clinical medicine ,DNA demethylation ,Endocrinology ,Downregulation and upregulation ,Estrogen ,Internal medicine ,medicine.artery ,Internal Medicine ,medicine ,Uterine artery ,Demethylation - Abstract
The large-conductance Ca 2+ -activated K + (BK Ca ) channel is of critical importance in pregnancy-mediated increase in uterine artery vasodilation and blood flow. The present study tested the hypothesis that active DNA demethylation plays a key role in pregnancy-induced reprogramming and upregulation of BK Ca channel β1 subunit (BKβ1) in uterine arteries. Uterine arteries were isolated from nonpregnant and near-term pregnant sheep. Pregnancy significantly increased the expression of ten-eleven translocation methylcytosine dioxygenase 1 (TET1) in uterine arteries. A half-palindromic estrogen response element was identified at the TET1 promoter, and estrogen treatment increased TET1 promoter activity and TET1 expression in uterine arteries. In accordance, pregnancy and steroid hormone treatment resulted in demethylation of BKβ1 promoter by increasing 5-hydroxymethylcytosine and decreasing 5-methylcytosine at the CpG in the Sp1 -380 binding site that is of critical importance in the regulation of the promoter activity and BKβ1 expression. Inhibition of TET1 with fumarate significantly decreased BKβ1 expression in uterine arteries of pregnant animals and blocked steroid hormone–induced upregulation of BKβ1. Functionally, fumarate treatment inhibited pregnancy and steroid hormone–induced increases in BK Ca channel current density and BK Ca channel–mediated relaxations. In addition, fumarate blocked pregnancy and steroid hormone–induced decrease in pressure-dependent myogenic tone of the uterine artery. The results demonstrate a novel mechanism of estrogen-mediated active DNA demethylation in reprogramming of BK Ca channel expression and function in the adaption of uterine circulation during pregnancy.
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- 2017
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36. Computational Modeling Approach in Probing the Effects of Cytosine Methylation on the Transcription Factor Binding to DNA
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Kimberley R. Cousins, Lubo Zhang, Shumei Yang, and John Tenayuca
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Models, Molecular ,0301 basic medicine ,Sp1 Transcription Factor ,Electrophoretic Mobility Shift Assay ,Article ,Cytosine ,03 medical and health sciences ,chemistry.chemical_compound ,Epigenetics of physical exercise ,Drug Discovery ,Epigenetics ,Binding site ,Binding Sites ,Hydrogen Bonding ,DNA ,General Medicine ,Methylation ,DNA-binding domain ,DNA Methylation ,030104 developmental biology ,chemistry ,Biochemistry ,CpG site ,DNA methylation ,Protein Binding - Abstract
Introduction: Cytosine methylation at CpG dinucleotides is a chief mechanism in epigenetic modification of gene expression patterns. Previous studies demonstrated that increased CpG methylation of Sp1 sites at -268 and -346 of protein kinase C e promoter repressed the gene expression. Materials & Methods: The present study investigated the impact of CpG methylation on the Sp1 binding via molecular modeling and electrophoretic mobility shift assay. Each of the Sp1 sites contain two CpGs. Methylation of either CpG lowered the binding affinity of Sp1, whereas methylation of both CpGs produced a greater decrease in the binding affinity. Computation of van der Waals (VDW) energy of Sp1 in complex with the Sp1 sites demonstrated increased VDW values from one to two sites of CpG methylation. Molecular modeling indicated that single CpG methylation caused underwinding of the DNA fragment, with the phosphate groups at C1, C4 and C5 reoriented from their original positions. Methylation of both CpGs pinched the minor groove and increased the helical twist concomitant with a shallow, hydrophobic major groove. Additionally, double methylation eliminated hydrogen bonds on recognition helix residues located at positions -1 and 1, which were essential for interaction with O6/N7 of G-bases. Bonding from linker residues Arg565, Lys595 and Lys596 were also reduced. Methylation of single or both CpGs significantly affected hydrogen bonding from all three Sp1 DNA binding domains, demonstrating that the consequences of cytosine modification extend beyond the neighboring nucleotides. Results: The results indicate that cytosine methylation causes subtle structural alterations in Sp1 binding sites consequently resulting in inhibition of side chain interactions critical for specific base recognition and reduction of the binding affinity of Sp1.
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- 2017
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37. miR-217 inhibits the migration and invasion of HeLa cells through modulating MAPK1
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Lihong Zhu, Shumei Yang, and Jianfeng Wang
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Adult ,0301 basic medicine ,cervical cancer ,Cell ,Down-Regulation ,Uterine Cervical Neoplasms ,Apoptosis ,Cell Line ,Flow cytometry ,HeLa ,03 medical and health sciences ,0302 clinical medicine ,Cell Movement ,Cell Line, Tumor ,Genetics ,medicine ,Humans ,Neoplasm Invasiveness ,Viability assay ,Protein kinase A ,microRNA-217 ,Mitogen-Activated Protein Kinase 1 ,biology ,medicine.diagnostic_test ,Chemistry ,Kinase ,Cell Cycle ,Articles ,General Medicine ,Middle Aged ,Cell cycle ,biology.organism_classification ,Molecular biology ,Up-Regulation ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,HEK293 Cells ,030104 developmental biology ,medicine.anatomical_structure ,phosphorylated extracellular signal-regulated kinase 1/2/extracellular signal-regulated kinase 1/2 ,030220 oncology & carcinogenesis ,Female ,HeLa Cells - Abstract
MicroRNA (miR)-217 serves a pivotal role in the progression of colorectal cancer, renal cell carcinoma and glioma, however, the role of miR-217 in cervical cancer (CC) remains unclear. In the present study, the mechanism of miR-217 in cervical cancer was explored. The mRNA expression of miR-217 and mitogen-activated protein kinase 1 (MAPK1) were assessed using reverse transcription-quantitative polymerase chain reaction analysis. Cell Counting-Kit 8, wound-healing and Transwell assays were performed to detect cell viability, migration and invasion, respectively. Apoptosis and cell cycle were determined by flow cytometry. TargetScan 7.2 and dual-luciferase reporter assays were respectively used to determine miR-217 target genes and their binding capacities. The protein expression levels of MAPK1, phosphorylated (p)-extracellular signal-regulated kinase 1/2 (ERK1/2)/ERK1/2, Bcl-2, Bax and cleaved caspase-3 were quantified by western blotting. It was found that miR-217 was downregulated in patients with CC and in CC cells. The viability, migration and invasion of cells were suppressed by a miR-217 mimic. It was also found that apoptosis was increased and cell cycle was inhibited by the miR-217mimic, which was supported by changes in Bcl-2, Bax and cleaved caspase-3. MAPK1 was upregulated in patients with CC and was a target gene of miR-217. MAPK1 reversed the inhibition of miR-217 on cell viability, migration, invasion and apoptosis. The protein levels of MAPK1 and p-ERK1/2, which were higher in the mimic MAPK1 group than those in the control or mimic groups, were ameliorated by PD98059. The results of the present study demonstrated that miR-217 had an anti-CC effect and may be effectively used in the treatment of CC.
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- 2019
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38. Soluble glucocorticoid-induced tumor necrosis factor receptor regulates Helios expression in myasthenia gravis
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Zhibin Li, Shumei Yang, Wanling Jin, Huanyu Meng, Yi Li, Weifan Yin, and Huan Yang
- Subjects
0301 basic medicine ,Adult ,Male ,lcsh:Medicine ,Context (language use) ,chemical and pharmacologic phenomena ,HeliOS ,T-Lymphocytes, Regulatory ,General Biochemistry, Genetics and Molecular Biology ,Flow cytometry ,Pathogenesis ,03 medical and health sciences ,Ikaros Transcription Factor ,0302 clinical medicine ,Antigens, CD ,Glucocorticoid-Induced TNFR-Related Protein ,Myasthenia Gravis ,medicine ,Humans ,IL-2 receptor ,GITR ,Glucocorticoids ,medicine.diagnostic_test ,Chemistry ,Research ,lcsh:R ,Apyrase ,Cell Membrane ,FOXP3 ,hemic and immune systems ,Forkhead Transcription Factors ,General Medicine ,Regulatory T cells ,medicine.disease ,Myasthenia gravis ,Helios ,030104 developmental biology ,Solubility ,030220 oncology & carcinogenesis ,Tumor Necrosis Factors ,Cancer research ,Female ,GITRL ,Glucocorticoid ,medicine.drug - Abstract
Background Helios is important for functional and phenotype stability of regulatory T cells (Tregs). However, the role of Helios in autoimmune diseases and its regulation remains unclear. This study aimed to investigate the role of Helios+ Tregs in myasthenia gravis (MG) and glucocorticoid-induced tumor necrosis factor receptor (GITR) and its ligand (GITRL) in the modulation of Helios. Method Multicolor flow cytometry was performed to analyze Helios+ Tregs in peripheral blood from MG patients and healthy donors (HDs). Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of soluble GITRL/GITR in plasma. Tregs were isolated via magnetic separation and treated with recombinant GITRL and GITR-Fc. Membrane GITRL on Tregs and expression of Helios and other markers (FOXP3, CD25, CD39, CTLA-4, PD-L1 and IL-10) involved in immunosuppressive activity were determined by flow cytometry. Result Both Helios+ Tregs and soluble GITR were decreased in generalized MG (GMG) patients (n = 14), compared with HDs (n = 14) and ocular MG (OMG) patients (n = 16). Helios+ Tregs possessed greater immunosuppressive capacity compared to Helios− Tregs. Further analysis indicates soluble GITR was negatively correlated with quantitative MG score and promoted Helios expression and enhanced function of Tregs independently of membrane GITRL. Conclusion This work demonstrates abnormal changes in Helios+ Tregs and soluble GITR in MG, as well as direct regulation of Helios by GITR in the context of Tregs. This work provides new insight into the role of GITR in the regulatory pathway of Helios and pathogenesis of MG.
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- 2019
39. Selection of Internal Standards for Quantitative Matrix-Assisted Laser Desorption/Ionization Mass Spectrometric Analysis Based on Correlation Coefficients
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Ruxia Feng, Xianglei Kong, Lei Mu, and Shumei Yang
- Subjects
Analyte ,Materials science ,Correlation coefficient ,General Chemical Engineering ,Analytical chemistry ,Linearity ,General Chemistry ,Laser ,Article ,law.invention ,Ion ,lcsh:Chemistry ,Matrix-assisted laser desorption/ionization ,lcsh:QD1-999 ,law ,Desorption ,Quantitative analysis (chemistry) - Abstract
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) has shown its great success in the qualitative analysis of a wide range of organic and biological molecules. However, its application in quantitative analysis is still limited by the difficulty in the availability of isotope-labeled internal standards. The present work investigates the relationship between the correlation coefficient of the peak intensities of analyte and candidate internal standard ions and the linearity of possible quantitative analysis. Based on the two analyte examples, ciprofloxacin and substance P, the results show that the performance of the selected nonisotope-labeled internal standard is greatly related to the correlation coefficient. A high positive correlation coefficient (>0.7) between the ions of analyte and candidate standard can result in a good linearity (R2 > 0.98) and vice versa. The results provide a new way to select nonisotope-labeled internal standards for MALDI analysis and thus can be potentially applied in the rapid quantitative mass spectrometry.
- Published
- 2019
40. Malignant Peripheral Nerve Sheath Tumor in the Nasal Cavity of a Neonate: A Case Report
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Xiufang Chi, Shumei Yang, Yue Wang, Cheng Xing, Jiamin Gan, Haoming Yang, Hongyi Gao, Guo Sheng Liu, Sha Sha Han, and Chuan Nie
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Nasal cavity ,Pathology ,medicine.medical_specialty ,business.industry ,Malignant peripheral nerve sheath tumor ,Nasal Mass ,medicine.disease ,Trunk ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Otorhinolaryngology ,030220 oncology & carcinogenesis ,medicine ,In patient ,Differential diagnosis ,Head and neck ,business ,Pathological - Abstract
Malignant peripheral nerve sheath tumor (MPNST) is a rare tumor that can develop on the lining of nerves and within the network of nerve fibers in different organs, and it is commonly found in the head and neck, limbs, and trunk. These tumors can occur in patients of any age. They most commonly occur in adults aged 20 to 50 years; however, fewer cases of this tumor in children have been reported. To date, no neonatal case of MPNST in the nasal cavity has been reported. Here, we report the case of a 4-day-old female newborn who presented with a nasal mass that re-enlarged after surgery and was diagnosed as MPNST of the nasal cavity on the basis of pathological results. This is the first report of MPNST in the nasal cavity of a neonate. Differential diagnosis and treatment of nasal masses have been proposed in the related literature.
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- 2021
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41. Regulation of cAMP-dependent protein kinase: enzyme activation without dissociation
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Shumei Yang, Fletcher, William H., and Johnson, David A.
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Enzyme activation -- Research ,Protein kinases -- Research ,Biological sciences ,Chemistry - Abstract
Catalytic stimulation of cAMP-dependent protein kinase (cAPK) induced by cAMP can take place without holoenzyme dissociation. C subunits and cAMP-bound R square can be separated with a mild force. Morphochemical and biochemical studies suggest that cAPK can dissociate its units in vivo.
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- 1995
42. Chronic hypoxia upregulates DNA methyltransferase and represses large conductance Ca2+-activated K+ channel function in ovine uterine arteries†
- Author
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Lubo Zhang, Xiaohui Huang, Chiranjib Dasgupta, Shumei Yang, Daliao Xiao, Xiang-Qun Hu, and Man Chen
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Vasodilation ,030204 cardiovascular system & hematology ,Biology ,Decitabine ,DNA methyltransferase ,Gene Expression Regulation, Enzymologic ,Potassium Channels, Calcium-Activated ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Pregnancy ,Internal medicine ,medicine.artery ,medicine ,Animals ,DNA (Cytosine-5-)-Methyltransferases ,Hypoxia ,Uterine artery ,Transcription factor ,Sheep ,Altitude ,Cell Biology ,General Medicine ,Hypoxia (medical) ,Uterine Artery ,030104 developmental biology ,Endocrinology ,Reproductive Medicine ,DNA methylation ,Azacitidine ,Female ,medicine.symptom ,Ex vivo - Abstract
Chronic hypoxia during gestation suppresses large-conductance Ca2+-activated K+ (BKCa) channel function and impedes uterine arterial adaptation to pregnancy. This study tested the hypothesis that chronic hypoxia has a direct effect in upregulating DNA methyltransferase (DNMT) and epigenetically repressing BKCa channel beta-1 subunit (KCNMB1) expression in uterine arteries. Resistance-sized uterine arteries were isolated from near-term pregnant sheep maintained at ∼300 m above sea level or animals acclimatized to high-altitude (3,801 m) hypoxia for 110 days during gestation. For ex vivo hypoxia treatment, uterine arteries from normoxic animals were treated with 21.0% O2 or 10.5% O2 for 48 h. High-altitude hypoxia significantly upregulated DNMT3b expression and enzyme activity in uterine arteries. Similarly, ex vivo hypoxia treatment upregulated DNMT3b expression and enzyme activity that was blocked by a DNMT inhibitor 5-aza-2'-deoxycytidine (5-Aza). Of importance, 5-Aza inhibited hypoxia-induced hypermethylation of specificity protein (SP) 1 binding site at the KCNMB1 promoter and restored transcription factor binding to the KCNMB1 promoter, resulting in the recovery of KCNMB1 gene expression in uterine arteries. Furthermore, 5-Aza blocked the effect of hypoxia and rescued BKCa channel activity and reversed hypoxia-induced decrease in BKCa channel-mediated relaxations and increase in myogenic tone of uterine arteries. Collectively, these results suggest that chronic hypoxia during gestation upregulates DNMT expression and activity, resulting in hypermethylation and repression of KCNMB1 gene and BKCa channel function, impeding uterine arterial adaptation to pregnancy.
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- 2017
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43. Dimetallofullerene M2@C100 or carbide cluster fullerene M2C2@C98 (M = La, Y, and Sc): which ones are more stable?
- Author
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Xiaodi Bao, Shumei Yang, Xianglei Kong, and Lei Mu
- Subjects
Materials science ,Fullerene ,010405 organic chemistry ,General Chemical Engineering ,Nanotechnology ,General Chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Carbide ,Metal ,Electric arc ,visual_art ,visual_art.visual_art_medium ,Cluster (physics) ,Endohedral fullerene ,Physical chemistry ,Chemical stability ,Density functional theory - Abstract
The geometric and thermodynamic stability of the M2C100 (M = La, Y, and Sc) series was systematically investigated using density functional theory calculations on the level of B3LYP/6-31G(d) ∼ Lanl2dz. In all the cases, M2@D5(285913)-C100 isomers are the lowest-energy species. However, carbide endohedral fullerenes M2C2@C1(230933)-C98 present excellent thermodynamic stabilities, except for those with La metal. The main product in electric arc experiments at temperatures lower than 3500 K for La2C100 should be La2@D5(285913)-C100, which was successfully synthesized previously; for Y and Sc, the predicted main products in these experiments should be M2C2@C1(230933)-C98. Further analysis of the geometric structures of the M2C100 series showed that the dimetallofullerenes M2@C100 have greater effects on the shapes of cages than M2C2@C98. These results provide some valuable guidance for the synthesis and characterization of large endohedral fullerenes including La, Y or Sc.
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- 2017
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44. Collision-induced dissociation mass spectrometry of phosphorus cluster anionsP2m+1−(3 ≤ m ≤ 20)
- Author
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Xianglei Kong, Shumei Yang, and Lei Mu
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Collision-induced dissociation ,Chemistry ,010401 analytical chemistry ,Analytical chemistry ,010402 general chemistry ,Condensed Matter Physics ,Mass spectrometry ,01 natural sciences ,Dissociation (chemistry) ,0104 chemical sciences ,Physical and Theoretical Chemistry ,Instrumentation ,Spectroscopy ,Dissociation pathway - Abstract
Phosphorus cluster anions were generated and investigated using collision-induced dissociation mass spectrometry. Results show that the primary dissociation channels of P 2 m + 1 − (3 ≤ m ≤ 11) are generally characterized by the loss of a P 2 unit, which distinguishes them from their counterpart cations. However, P 11 − and P 13 − are two exceptions. The former is characterized by the loss of a P 4 unit, and the latter is characterized by two parallel dissociation channels, which lead to the loss of P 2 and P 6 units. The dissociation behaviors of larger cluster anions of P 8 k + 1 − ( k = 3–5) are more complex. The primary dissociation pathway of P 25 − is the loss of a P 8 unit, and those of P 33 − and P 41 − are the loss of P 16 and P 2 units respectively. Theoretical calculations were performed for anions of P 2 m + 1 − (3 ≤ m ≤ 9). Results show that their dissociation channels characterized by the loss of the P 2 unit are more thermodynamically favored, which is generally consistent with the experimental results.
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- 2016
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45. Structure of Pro 4 H + investigated by infrared photodissociation (IRPD) spectroscopy and theoretical calculations
- Author
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Shumei Yang, Xianglei Kong, Lei Mu, and Ruxia Feng
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Chemistry ,Infrared ,Electrospray ionization ,010401 analytical chemistry ,Photodissociation ,Analytical chemistry ,General Chemistry ,010402 general chemistry ,Mass spectrometry ,01 natural sciences ,Spectral line ,0104 chemical sciences ,Ion ,Cluster (physics) ,Spectroscopy - Abstract
Combining with electrospray ionization (ESI) mass spectrometry, infrared photodissociation (IRPD) spectroscopy is a powerful method to study structures of cluster ions in the gas phase. In this paper, infrared photodissociation spectrum of Pro 4 H + in the range of 2700–3600 cm −1 was obtained experimentally. Both theoretically predicted spectra of the two most stable isomers of Pro4-1 and Pro4-2 obtained at the level of M062X/6-31 + G(d, p) are in good consistent with the experimental results. The two isomers have similar structures and close energies. Both of them only consist of zwitterionic units, indicating the strong salt-bridged interactions inside the clusters. And the calculated collision cross section (ccs) of Pro4-1 is found to be very close to the experimental result previously reported.
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- 2016
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46. Mono- and dinuclear complexes of a new binucleating porphyrin, alpha, alpha-5,15-bis(o- nicotinoylamino phenyl)-2,8,12,18-tetraethyl-3,7,13, 17-tetramethyl-porphyrin. Crystal structures of a mononuclear nickel(II) complex and a binuclear Cu-Pt complex
- Author
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Woo, L. Keith, Maurya, Mannar R., Jacobson, Robert A., Shumei Yang, and Ringrose, Sharon L.
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Porphyrins -- Research ,Coordination compounds -- Research ,Nickel -- Research ,Copper -- Research ,Chemistry - Abstract
The complex H2(di o-aminophenyl etioporphyrin) (DPE) can undergo condensation with the addition of nicotinoyl chloride HCl in triethylamine to produce (H2 DPE)-(py)2 in 76% yield. Insertion of Ni(II) and Cu(II) in the binucleating porphyrin core results in the formation of mononuclear complexes having a free pyridine binding site. Moreover, the introduction of another metal group via M'(DMSO)2Cl2 reactions in the mononuclear complex, leads to the formation of the dinuclear (M- DPE)-(py)2M'Cl2, wherein M represents Pd, Pt and Zn.
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- 1992
47. Phosphorus Clusters and Quantum Dots
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Xianglei Kong, Lei Mu, Shumei Yang, and Ming Zhou
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Materials science ,chemistry ,Quantum dot ,Chemical physics ,Phosphorus ,chemistry.chemical_element - Published
- 2019
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48. Electronic excitation transport in photosynthesis and crystal and molecular structures of porphyrin compounds
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Shumei Yang
- Subjects
Crystal ,chemistry.chemical_compound ,chemistry ,Photosynthesis ,Photochemistry ,Porphyrin ,Excitation - Published
- 2018
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- View/download PDF
49. Medium-sized phosphorus cluster cationsP+2m+1(6 ≤ m ≤ 32) studied by collision-induced dissociation mass spectrometry
- Author
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Xiaodi Bao, Hong Yin, Shumei Yang, Lei Mu, and Xianglei Kong
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Collision-induced dissociation ,Chemistry ,Analytical chemistry ,Mass spectrometry ,Spectroscopy ,Dissociation (chemistry) ,Dissociation channel ,Dissociation pathway - Abstract
Medium-sized phosphorus cluster cations were generated by laser ablation of red phosphorus and investigated by the method of collision-induced dissociation mass spectrometry. Experimental results show that the primary dissociation channels of phosphorus cluster cations of P+2m+1 (6 ≤ m ≤ 11) are all characterized by the loss of P4 unit. For larger cluster cations, their dissociation pathways were more complex. For those magic cations of P+8k+1 observed previously, their dissociation pathways progressively change from the loss of P4 unit (for k = 3) to the loss of P8 unit (for k = 4, 5). A new dissociation pathway characterized by the loss of P10 unit was also indentified for larger cations of P+8k+1 (6 ≤ k ≤ 8). Theoretical calculation also shows that, for cations of P+2m+1 (4 ≤ m ≤ 10), the dissociation channel characterized by the loss of P4 unit is more energetically favorable than other dissociation channels, which is in good agreement with the experimental results. Copyright © 2015 John Wiley & Sons, Ltd.
- Published
- 2015
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50. Hypoxia Represses ER-α Expression and Inhibits Estrogen-Induced Regulation of Ca 2+ -Activated K + Channel Activity and Myogenic Tone in Ovine Uterine Arteries
- Author
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Shumei Yang, Lubo Zhang, Xiang-Qun Hu, Daliao Xiao, Chiranjib Dasgupta, and Man Chen
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medicine.medical_specialty ,Estrogen receptor ,Biology ,Decitabine ,Article ,Upstream Stimulatory Factor ,Pregnancy ,Internal medicine ,Gene expression ,Internal Medicine ,medicine ,Animals ,Hypoxia ,Large-Conductance Calcium-Activated Potassium Channel alpha Subunits ,Promoter Regions, Genetic ,Progesterone ,Regulation of gene expression ,Sheep ,Estradiol ,Estrogen Receptor alpha ,Methylation ,DNA Methylation ,Hypoxia (medical) ,Acetylcysteine ,Pregnancy Complications ,Uterine Artery ,Endocrinology ,Gene Expression Regulation ,DNA methylation ,Azacitidine ,Female ,Vascular Resistance ,medicine.symptom ,Reactive Oxygen Species ,Estrogen receptor alpha - Abstract
Previous in vivo study demonstrated that chronic hypoxia during gestation was associated with estrogen receptor-α (ER-α) gene repression in ovine uterine arteries. Yet, it remains undetermined whether hypoxia had a direct effect and if DNA methylation played a causal role in hypoxia-mediated ER-α gene repression. Thus, this study tested the hypothesis that prolonged hypoxia has a direct effect and increases promoter methylation resulting in ER-α gene repression and inhibition of estrogen-mediated adaptation of uterine vascular tone. Uterine arteries isolated from nonpregnant and pregnant sheep were treated ex vivo with 21.0% O 2 and 10.5% O 2 for 48 hours. Hypoxia significantly increased ER-α promoter methylation at both specificity protein-1 and upstream stimulatory factor binding sites, decreased specificity protein-1 and upstream stimulatory factor binding to the promoter, and suppressed ER-α expression in uterine arteries of pregnant animals. Of importance, the effects of hypoxia were blocked by a methylation inhibitor 5-aza-2′-deoxycytidine. In addition, hypoxia abrogated steroid hormone–mediated increase in ER-α expression and inhibited the hormone-induced increase in large-conductance Ca 2+ -activated K + channel activity and decrease in myogenic tone in uterine arteries of nonpregnant animals, which were reversed by 5-aza-2′-deoxycytidine. The results provide novel evidence of a direct effect of hypoxia on heightened promoter methylation that plays a causal role in ER-α gene repression and ablation of steroid hormone–mediated adaptation of uterine arterial large conductance Ca 2+ -activated K + channel activity and myogenic tone in pregnancy.
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- 2015
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