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191.
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   
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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   
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电子医疗数据已成为大数据时代开展药品安全主动监测的重要资源。基于此确认药品与不良事件是否存在关联,要回归传统的流行病学研究设计,选取恰当的对照进行对比。本文主要阐述不同对照选取的原理、适用情形,介绍、评价并比较各种对照选取的思路与参数,引入对照选择批量化实现的进展性成果,以期为我国利用电子医疗数据开展上市后药品安全性监测提供方法学参考。  相似文献   
196.

Background

The intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator (rt-PA) therapy is safe and efficient during the treatment of acute ischemic stroke. Nonetheless, the different outcomes among various stroke subgroups have limited data with regard to the safety and efficacy of cryptogenic stroke (CS). The present study compared the safety and efficacy when IVT with rt-PA was used for the treatment of CS and the other stroke subtypes.

Methods

This study classified the IVT with rt-PA patients within 4.5 hours after stroke onset, based on the trial of ORG 10172 in acute stroke treatment criteria in terms of diagnostic evaluation. The data were obtained from the Thrombolysis Implementation and Monitor of Acute Ischemic Stroke in China database, a large multicenter prospective registry. A multivariable logistic regression model was employed to compare the differences between the subtypes in symptomatic intracerebral hemorrhage (sICH) within 7 days and studied the mortality and the outcome during 90 days.

Results

In total, 1118 patients were recruited; of these, 131 (11.7%) suffered from CS and 987 (88.3%) with the other etiology. In the CS group, patients were younger than those in the other etiology groups (P < .001). Moreover, it had a lower prevalence of previous stroke (P?=?.0117), receiving antiplatelet drug in 24 hours prior to thrombolysis (P?=?.0017), and functional independence (mRS > 1 before stroke, P?=?.003). The CS group had lower blood pressure (systolic blood pressure P?=?.0001; diastolic blood pressure; P?=?.0212) before thrombolysis, atrial fibrillation (P < .001), and diabetes mellitus (P?=?.0005). Transient ischemic attack, hypertension, hyperlipidemia, blood glucose, receiving anticoagulants in 24 hours prior to thrombolysis, and standard dosage of rt-PA were equally distributed in both groups. After the adjustment of confounders between the CS and the other subgroups, no obvious differences were observed in sICH rate and mortality (P > .05) The CS patients exhibited excellent recovery (mRS, 0-1; 63.78%) and functional independence (mRS, 0-2; 74.8%) than the large artery atherosclerosis patients.

Conclusions

IVT with rt-PA is a safe and effective method for the treatment of CS patients.  相似文献   
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Background: Previous genome-wide association study (GWAS) has revealed the association between MYP10 at 8p23 and MYP15 at 10q21.1 and high myopia (HM) in a French population. This study is managed to discover the connection between some single nucleotide polymorphism (located at MYP10 and MYP15) and Han Chinese HM.

Methods and Results: This case-control association study contained 1673 samples, including 869 ophthalmic patients and 804 controls. Twelve tag SNPs have been selected from the MYP10 and MYP15 loci and genotyped by SNaPshot method. Among 12 SNPs, rs4840437 and rs6989782 in TNKS gene were found significant association with HM. Carriers of rs4840437G allele and rs4840437GG genotype created a low risk of high myopia (P = .036, OR = 0.81, 95%CI = 0.71–0.93; P = .016, OR = 0.73, 95%CI = 0.56–0.96; respectively). Carriers of rs6989782T allele and rs6989782TT+CT genotype also had a decreased risk of high myopia (P = .048, OR = 0.82, 95%CI = 0.71–0.94; P = .006, OR = 0.74, 95%CI = 0.59–0.92; respectively). Other 10 SNPs displaced nonsignificant association with HM. Additionally, the risk haplotype AC and the protective haplotype GT, generated by two SNPs in TNKS, were considerably more likely to be association with HM (for AC, P = .002 and OR = 1.26; for GT, P = .027 and OR = 0.84).

Conclusions: Our results demonstrated that some heritable variants in the TNKS gene are associated with HM in the Han population. The possible functions of TNKS in the development and pathogenesis of hereditary high myopia still require further researches to identify.  相似文献   

199.
王翔 《中国药物评价》2019,36(5):392-396
目的:通过研究风险评估工具,结合企业临床试验数据管理风险评估实例,从实际应用角度出发,提出完善药物临床试验数据管理过程中应用风险评估的意见建议。方法:运用文献分析方法、案例分析法,分析和借鉴成功的经验。结果与结论:我国的药品研制单位应根据具体临床试验特点和法规要求,利用合适的风险管理工具,对临床试验数据管理过程进行评估,根据评估结果合理制定并实施数据管理策略,达到保证临床试验数据完整、可靠的目的。  相似文献   
200.
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