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101.
Helicobacter pylori (H. pylori) is a main risk factor for gastric cancer (GC). Epithelial-mesenchymal transition (EMT) is involved in the development and progression of H. pylori-associated GC. However, the exact molecular mechanism of this process remains unclear. The AKT/GSK3β signaling pathway has been demonstrated to promote EMT in several types of cancer. The present study investigated whether H. pylori infection induced EMT, and promoted the development and metastasis of cancer in the normal gastric mucosa, and whether this process was dependent on AKT activation. The expression levels of the EMT-associated proteins, including E-cadherin and N-cadherin, were determined in 165 gastric mucosal samples of different disease stages by immunohistochemical analysis. The expression levels of E-cadherin, N-cadherin, AKT, phosphorylated (p-)AKT (Ser473), GSK3β and p-GSK3β (Ser9) were further determined in H. pylori-infected Mongolian gerbil gastric tissues and cells co-cultured with H. pylori by immunohistochemical analysis and western blotting. The results indicated that the expression levels of the epithelial marker E-cadherin were decreased, whereas the expression levels of the mesenchymal marker N-cadherin were increased during gastric carcinogenesis. Their expression levels were associated with H. pylori infection. Furthermore, H. pylori infection resulted in downregulation of E-cadherin expression and upregulation of N-cadherin expression in Mongolian gerbils and GES-1 cells. In addition, an investigation of the associated mechanism of action revealed that p-AKT (Ser473) and p-GSK3β (Ser9) were activated in GES-1 cells following co-culture with H. pylori. Furthermore, following pretreatment of the cells with the AKT inhibitor VIII, the expression levels of E-cadherin, N-cadherin, p-AKT and p-GSK3β did not show significant differences between GES-1 cells that were co-cultured with or without H. pylori. The levels of p-AKT and p-GSK3β were increased in H. pylori-infected Mongolian gerbils. In conclusion, the present study demonstrated that H. pylori infection activated AKT and resulted in the phosphorylation and inactivation of GSK3β, which in turn promoted early stage EMT. These effects were AKT-dependent. This mechanism may serve as a prerequisite for GC development.  相似文献   
102.
103.
医学生的责任心体现在其一定行为表现上,是医学生职业精神培养的重要内涵,因此对影响医学生责任心的负向行为进行一定的干预具有重要意义。分析国内外医学院校应用责任指数考核在医学生行为督导养成的评价研究,遵循我国口腔医学专业人才培养的规律,结合口腔医学生成长的特点,借鉴职业精神考核的相关指标——责任指数考核法,试设计口腔医学生行为责任指数测评方案,并预设可行性,为拓宽口腔医学生职业精神的培养提供思路。  相似文献   
104.
新医改环境下,临床医学人才的医德培养愈发重要,也越来越引起管理层重视。而医院文化环境对研究生医德培养可以起着潜移默化的引领作用,优秀的医院文化,能塑造并铸就研究生良好信念,强化研究生医德养成。结合传染病专科医院自身文化环境特点,探索传染病学研究生医德培养方式,对于传染病专科医院研究生医德培养具有一定理论指导意义。  相似文献   
105.
Temporomandibular joint osteoarthritis (TMJOA) is a chronic degenerative disease for which the underlying mechanism still remains unclear. Compared with apoptosis and autophagy, necroptosis causes greater harm to tissue homeostasis by releasing damage-associated molecular patterns (DAMPs). However, the role of necroptosis and downstream key DAMPs in TMJOA is unknown. Here, rodent models of TMJOA were established by the unilateral anterior crossbite (UAC). Transmission electron microscopy (TEM) and immunohistochemistry of receptor interacting protein kinase 3 (RIPK3)/phosphorylation of mixed lineage kinase domain-like protein (pMLKL) were conducted to evaluate the occurrence of necroptosis in vivo. The therapeutic effects of blocking necroptosis were achieved by intra-articularly injecting RIPK3 or MLKL inhibitors and using RIPK3 or MLKL knockout mice. In vitro necroptosis of condylar chondrocyte was induced by combination of tumor necrosis factor alpha (TNFα), second mitochondria-derived activator of caspases (SMAC) mimetics and carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (z-VAD-fmk). The possible DAMPs released by necroptotic chondrocytes were screened by quantitative proteomics and blocked by specific antibody. Translucent cytosol, swollen organelles, and ruptured cell membranes, features of necroptosis, were frequently manifested in chondrocytes at the early stage of condylar cartilage degeneration in TMJOA, which was accompanied by upregulation of RIPK3/pMLKL. Inhibiting or knocking out RIPK3/MLKL significantly prevented cartilage degeneration. DAMPs released by necroptotic condylar chondrocytes, such as syndecan 4 (SDC4) and heat shock protein 90 (HSP90), were verified. Furthermore, blocking the function of SDC4 significantly attenuated the expression of TNFα in cartilage and synovium, and accordingly increased cartilage thickness and reduced synovial inflammation. Thus, the necroptotic vicious cycle of TNFα-SDC4-TNFα contributes to cartilage degeneration and synovitis, and can serve as a potential therapeutic target for treating TMJOA. © 2022 American Society for Bone and Mineral Research (ASBMR).  相似文献   
106.
Abstract

Oxidative stress (OS) has been proposed to play a role in the development of EMs. Peroxiredoxins are a family of antioxidant proteins that exhibit peroxidase activity in a thioredoxin-dependent manner, protecting cells against OS. The Western blotting results showed that the relative expression of PRDX4 was significantly increased in ectopic endometria compared with the normal endometria of EMs-free (p?<?.05). The H2O2 concentration was also significantly higher in the ectopic endometrium. PRDX4 siRNA was transfected into primary ectopic endometrial stromal cells (EESCs). The viability of the transfected EESCs was measured by CCK-8 assay, and the results showed significantly decreased cell viability. Furthermore, the apoptosis rate and ROS generation in flow cytometry assays were significantly increased after the knockdown of PRDX4 expression (p?<?.05). Scratch assays and transwell assays revealed that decreased expression of PRDX4 mediated by siRNA inhibited EESC migration and invasion. In conclusion, these findings indicate the potential role of PRDX4 in the development of EMs and PRDX4 as a possible therapeutic target for EMs treatment.  相似文献   
107.
To evaluate the efficacy of computed tomography (CT) guided single radiofrequency thermocoagualtion (RFT) in 1137 patients with idiopathic trigeminal neuralgia after a follow-up period of 11 years, specially focused on duration of pain relief in different branches of trigeminal nerve, side effect, and complications.Retrospective study of patients with idiopathic trigeminal neuralgia treated with a single CT guided RFT procedure between January 2002 and December 2013.The mean follow-up time was 46.14 ± 30.91 months. Immediate postprocedure pain relief was 98.4%. V2 division obtained the best pain relief rate: 91%, 89%, 80%, 72%, 60%, and 54% at 1, 3, 5, 7, 9, and 11 years, respectively. No statistical difference pairwise comparison was in other groups. The complications included masseter muscle weakness, corneitis, diplopia, ptosis, hearing loss, limited mouth opening, and low pressure headache. Masticatory weakness mostly occurred in patients with V3 branch involvement, while Corneitis and Diplopia all in patients with V1 branch involvement. No mortalities observed during or after RFT.All different branches division of trigeminal neuralgia achieved comparable satisfactory curative effect; V2 obtained the best excellent pain relief, after RFT procedure. Facial numbness is inevitable after RFT, which patients who have pain in all 3 trigeminal divisions and patients who desire no facial numbness should be cautious. Masticatory weakness is mainly related with V3 injured, while Corneitis and Diplopia in patients with V1 injured by RFT.  相似文献   
108.
109.
Sodium butyrate is a histone deacetylase inhibitor that affects various types of brain damages. To investigate the effects of sodium butyrate on hippocampal dysfunction that occurs after whole-brain irradiation in animal models and the effect of sodium butyrate on radiation exposure-induced cognitive impairments,adult C57BL/6 mice were intraperitoneally treated with 0.6 g/kg sodium butyrate before exposure to 10 Gy cranial irradiation. Cognitive impairment in adult C57BL/6 mice was evaluated via an object recognition test 30 days after irradiation. We also detected the expression levels of neurogenic cell markers(doublecortin)and phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor. Radiation-exposed mice had decreased cognitive function and hippocampal doublecortin and phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor expression. Sodium butyrate pretreatment reversed these changes. These findings suggest that sodium butyrate can improve radiation-induced cognitive dysfunction through inhibiting the decrease in hippocampal phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor expression. The study procedures were approved by the Institutional Animal Care and Use Committee of Korea Institute of Radiological Medical Sciences(approval No. KIRAMS16-0002) on December 30, 2016.  相似文献   
110.
张明  杨洋  白楠 《现代药物与临床》2019,34(10):3132-3135
目的 了解解放军总医院抗震颤麻痹药物的应用情况与用药趋势。方法 采用世界卫生组织(WHO)推荐的以限定日剂量(DDD)为指标的分析方法,对2015-2017年解放军总医院抗震颤麻痹药物的销售金额、用药频度(DDDs)、日均费用(DDC)及排序比(B/A)等进行统计分析。结果 普拉克索、多巴丝肼和恩他卡朋的用药金额始终处于前3位,普拉克索的用药金额逐渐上升,卡比多巴/左旋多巴的用药金额逐渐下降;DDDs排序列前2位的是多巴丝肼和司来吉兰,多巴丝肼的DDDs逐年上升,一直处于第1位;2015-2016年各种抗震颤麻痹药物的DDC较为稳定,2016-2017年各种抗震颤麻痹药物的DDC开始略有下降;除普拉克索和恩他卡朋的B/A始终小于1.00,其他抗震颤麻痹药物的B/A均在1.00以上波动。结论 解放军总医院抗震颤麻痹药物的使用较为合理,其中多巴丝肼、普拉克索和司来吉兰具有很好的市场前景。  相似文献   
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