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131.
Melatonin induces apoptosis in many different cancer cell lines, including colorectal cancer. However, the precise mechanisms involved remain largely unresolved. In this study, we provide evidence to reveal a new mechanism by which melatonin induces apoptosis of colorectal cancer LoVo cells. Melatonin at pharmacological concentrations significantly suppressed cell proliferation and induced apoptosis in a dose‐dependent manner. The observed apoptosis was accompanied by the melatonin‐induced dephosphorylation and nuclear import of histone deacetylase 4 (HDAC4). Pretreatment with a HDAC4‐specific siRNA effectively attenuated the melatonin‐induced apoptosis, indicating that nuclear localization of HDAC4 is required for melatonin‐induced apoptosis. Moreover, constitutively active Ca2+/calmodulin‐dependent protein kinase II alpha (CaMKIIα) abrogated the melatonin‐induced HDAC4 nuclear import and apoptosis of LoVo cells. Furthermore, melatonin decreased H3 acetylation on bcl‐2 promoter, leading to a reduction of bcl‐2 expression, whereas constitutively active CaMKIIα(T286D) or HDAC4‐specific siRNA abrogated the effect of melatonin. In conclusion, the present study provides evidence that melatonin‐induced apoptosis in colorectal cancer LoVo cells largely depends on the nuclear import of HDAC4 and subsequent H3 deacetylation via the inactivation of CaMKIIα.  相似文献   
132.
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   
133.
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   
134.
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   
135.
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   
136.
137.
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   
138.
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   
139.
SEPT9是13个Septin同源基因家族之一,参与调控众多过程,包括细胞分裂、细胞极化、细胞迁移以及线粒体分裂等。研究表明在众多肿瘤中,SEPT9都发挥着作用,尤其在结直肠肿瘤研究领域,外周血SEPT9基因甲基化检测更是研究热点,其检测的敏感度和特异度相对于其他糖蛋白肿瘤标志物、粪便隐血试验和粪便免疫化学测试等更具有优势,相对于结直肠镜等侵入性检查更节约成本,同时有着更好的依从性。本文对SEPT9的功能、与结直肠癌之间的关系以及对结直肠肿瘤的筛查及诊断价值做一综述。  相似文献   
140.
目的探讨心理护理在ICU重症护理中的效果。方法选定本科于2017年6月-2019年8月收诊的ICU重症患者86例,等距抽样法分为对照组(43例,传统式护理)与观察组(43例,心理护理联合传统式护理)2组,比较2组ICU重症患者的护理满意率、情绪评分(SAS/SDS)指标。结果观察组ICU重症患者干预结束后的满意率高于对照组(P<0.05);观察组ICU重症患者干预结束后的SAS评分(32.52±3.26)分、SDS评分(30.09±3.45)分均低于对照组(P<0.05)。结论心理护理应用于ICU重症患者,可对其满意度、安全性进行保证。  相似文献   
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