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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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本文报道产前超声诊断胎儿右房异构一例。孕妇孕24周产前超声检查发现胎儿左位心合并复杂心血管畸形(右心室双出口、房室间隔缺损、肺动脉发育不良、双侧上腔静脉、心下型完全型肺静脉异位引流)、胃泡位于腹腔右侧、中位肝、可疑无脾、腹主动脉与下腔静脉位于脊柱左侧、双侧支气管呈右侧支气管对称形态,综合考虑右房异构可能。引产后经尸体解剖证实脾脏发育不良、右房异构。右房异构常合并复杂心血管畸形,因此产前超声发现复杂心血管畸形时,应警惕右房异构的可能。右房异构病死率极高,产前诊断具有重要意义。  相似文献   
74.

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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目的 探讨米索前列醇联合依沙吖啶在中晚期妊娠引产中的应用效果。方法 选取西安交通大学附属3201医院2012年1月—2017年12月收治的138例中晚期妊娠引产患者,按引产方式分为对照组、观察组,各69例。对照组使用乳酸依沙吖啶注射液进行引产,观察组在对照组的基础上联合使用米索前列醇进行引产。比较两组引产效果、胎儿娩出时间、阴道出血量及不良反应的发生情况。结果 观察组引产有效率是100%,显著高于对照组的91.75%(P<0.05)。观察组胎儿娩出时间<35 h的人数占比显著高于对照组(P<0.05)。观察组患者阴道出血量显著低于对照组(P<0.05),两组不良反应的发生率间差异不显著。结论 米索前列醇联合依沙吖啶在中晚期妊娠引产中的效果较好,可显著提高引产有效率、缩短胎儿娩出时间,值得临床应用。  相似文献   
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天麻素是从兰科植物天麻的块茎中提取分离而得,现已人工合成。天麻素药理作用广泛,如镇痛、镇静安眠、促智、保护神经元、降血压、抗惊厥、抗癫痫、抗氧化、抗衰老、改善微循环等,且安全、无明显毒副作用,其相关制剂在临床上亦被广泛用于心脑血管及神经精神系统疾病,如头痛、冠心病、高血压、后循环缺血性眩晕、突发性耳聋、癫痫、神经衰弱及脑卒中等。考虑到天麻素临床治疗上述疾病常与其他药物或治疗方法联用,故其体内过程及其药代动力学性质不容忽视。目前,有关天麻素综述多集中于药理作用和临床应用方面,而其药代动力学综述鲜见报道。随着天麻素药代动力学研究日渐深入,本研究将从其样品前处理、测定方法、药物ADME过程及影响体内过程的因素等方面较系统全面地对天麻素近年来的药代动力学研究作一综述,以期对天麻素制剂工艺及临床联合配伍应用有所裨益。  相似文献   
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