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51.
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   
52.
肠易激综合征(Irritable bowel syndrome,IBS)是临床常见病、多发病,其治疗方法丰富,但部分患者疗效欠佳,发展成难治性IBS。目前国内外关于针灸治疗难治性IBS的临床随机对照试验尚不多见。本文立足试验方案设计的“PICOS”原则,从研究对象及诊断标准、干预措施、对照措施、结局指标四个方面入手,重点探讨针刺辅助治疗难治性肠易激综合征临床试验设计的关键要点。从选择特色优势病种、明确诊断标准、制定符合临床实际的干预方案、运用符合目标的安慰针刺、结合研究设计和目的选定结局指标几个角度,阐述试验相关环节设计的原因和思考。  相似文献   
53.
目的:建立HPLC/TQ-MS测定益母草中阿魏酸含量的方法并测定不同产地益母草中阿魏酸含量,评价益母草中阿魏酸对中成药调经止痛片及新生化颗粒的质量影响,为制定含有益母草并以阿魏酸为定量指标的中成药质量标准提供参考。方法:采用薄层色谱法及UPLC-Q/TOF定性鉴别及分析益母草中阿魏酸,采用HPLC/TQ-MS定量分析10批不同产地益母草中阿魏酸含量。基于定量分析结果及处方用量探讨益母草中阿魏酸含量对其中成药质量标准的影响。结果:薄层鉴别及UPLC-Q/TOF定性分析结果显示,10批不同产地益母草中均含有阿魏酸。HPLC/TQ-MS定量分析结果显示,益母草中阿魏酸含量在0.004 2%~0.006 5%之间。结论:益母草与当归、川芎等含有阿魏酸的药材配伍且其用量较大时,益母草中阿魏酸含量会对其质量评价产生一定的影响。  相似文献   
54.
痘病毒是自然界普遍存在的DNA病毒,能够高效表达外源基因,诱导较强的细胞免疫和体液免疫,受到基因治疗学者的广泛关注。痘病毒发生同源重组的概率较低,所以有效地筛选和纯化痘病毒十分重要。目前常用的筛选重组痘病毒方法有基于CRISPR进行筛选;根据报告基因GFP、LacZ、GPT等进行筛选;利用TK-和Brdu结合荧光进行筛选;利用药物抗性基因与荧光或显色基因融合,即可在药物筛选的同时观察荧光或显色基因表达情况。本文旨在对目前常用的痘病毒的筛选纯化方法进行综述。  相似文献   
55.
The objective of this study was to investigate the absorption behavior of chikusetsusaponin IVa (CHS‐IVa) in the rat intestine using single‐pass intestinal perfusion (SPIP) and to classify CHS‐IVa into the biopharmaceutics classification system (BCS). The equilibrium solubility of CHS‐IVa was determined by the shaker method. The absorption mechanism of CHS‐IVa in the intestine was studied by comparing the Peff of different concentrations of CHS‐IVa. The intestinal site dependence of CHS‐IVa absorption was studied by comparing the Peff of the same concentration of CHS‐IVa in different intestinal segments. The relationship between CHS‐IVa and intestinal efflux protein was studied by perfusion with an efflux protein inhibitor. The permeability of CHS‐IVa was investigated by comparing the Peff of CHS‐IVa and the reported value. The solubility of CHS‐IVa over the pH range 1.0–7.5 was 14.4 ± 0.29 to 16.9 ± 0.34 mg/ml. The Peff of CHS‐IVa in the duodenum was 1.76 × 10?3 to 2.00 × 10?3 cm/min. The Peff of CHS‐IVa in the jejunum was 1.26 × 10?3 to 1.39 × 10?3 cm/min. The Peff of CHS‐IVa in the ileum was 1.25 × 10?3 to 1.31 × 10?3 cm/min. The Peff of CHS‐IVa in the colon was 1.02 × 10?3 to 1.08 × 10?3 cm/min. There was no statistical difference of the Peff in the four segments at different CHS‐IVa concentrations. The Peff of CHS‐IVa (0.07, 0.7 and 7.0 mg/ml) were all notably smaller than the reported Peff (3.00 × 10?3 cm/min) in the jejunum. The Peff of CHS‐IVa was not influenced by verapamil (P‐gp inhibitor), indomethacin (MRP inhibitor) and pantoprazole (BCRP inhibitor). CHS‐IVa was classified as high solubility, low permeability and BCS III. The main absorptive tracts were the upper intestinal tracts and the rank order of intestinal permeability was duodenum > jejunum ≈ ileum > colon. The transport mechanism of CHS‐IVa in all intestinal segments might be primarily passive transport. CHS‐IVa was not a substrate of P‐gp, MRP and BCRP.  相似文献   
56.
57.
目的:对比解剖性肝脏体积(ALV)和功能性肝脏体积(FLV)与肝功能Child-Pugh分级的相关性。方法:选择温州医科大学附属第二医院育英儿童医院2014年1月至2019年4月同时行增强CT和Gd-EOB-DTPA增强MRI扫描的肝硬化患者25例。对所有患者进行肝功能Child-Pugh评分,检测所有入组患者每个肝段的Gd-EOB-DTPA增强MRI平扫期和肝胆特异期的信号对比增强率(CER),以CT扫描的数据为基础利用MI-3DVS计算每个肝段的ALV和全肝的FLV。分析ALV和FLV与肝功能Child-Pugh分级的相关性。结果:肝功能Child-Pugh分级与ALV呈负相关(r=-0.792,P<0.001),曲线拟合的决定系数(R2)=0.63;肝功能Child-Pugh分级与FLV亦呈负相关(r=-0.911,P<0.001),曲线拟合的R2=0.80。FLV与肝功能Child-Pugh分级有更显著的负相关性。结论:结合Gd-EOB-DTPA增强MRI平扫期和肝胆特异期的信号CER和ALV计算所得的FLV较ALV能更好地反映肝脏的功能状态。  相似文献   
58.
【摘要】 目的 探讨叙事医学护理干预对脑卒中患者的临床应用价值。方法 选取2017年7月?2019年7月辽 阳市中心医院收治的脑卒中患者128例作为研究对象,采用随机数字表法分为实验组65例与对照组63例。对照组采 取常规护理干预,实验组在此基础上给予叙事医学护理干预。比较两组患者干预前、干预3个月后焦虑、抑郁评分;生活 质量简明SF-36评分;睡眠情况、认知功能、神经功能、运动功能;以及干预3个月后生存质量改善情况与并发症发生情 况。结果 干预3个月后,两组焦虑自评量表(SAS)、抑郁自评量表(SDS)评分均显著低于干预前,且实验组显著低于 对照组(均P<0. 05);两组生活质量简明SF-36评分均显著高于干预前,且实验组明显优于对照组(均P<0. 05);两组 睡眠情况均显著优于干预前,且实验组睡眠总时间、睡眠效率明显高于对照组,而觉醒次数、入睡潜伏时间明显低于对 照组(均P<0.05);实验组生存质量改善率显著高于对照组(均P<0.05);两组简明精神状态量表(MMSE)、脑卒中神 经功能缺损评分表(NIHSS)、运动功能评定量表(FMA)评分均显著优于干预前,且实验组MMSE.FMA评分显著高于 对照组,NIHSS评分显著低于对照组(均P<0.05);实验组与对照组患者干预后并发症发生率差异无统计学意义(P> 0.05)。结论叙事医学护理干预可有效缓解脑卒中焦虑抑郁情绪,改善患者生活、生存质量,提高认知、神经及运动功能,护理效果明确。  相似文献   
59.
Background

There is an increasing incidence of elderly patients requiring emergency laparotomy. Our study compares the outcomes of elderly patients undergoing emergency laparotomy against the outcomes of non-elderly patients.

Methodology

Patients who underwent emergency laparotomy between 2015 and 2017 from the National University Hospital, Singapore, were included. Apart from demographic data, indication of surgery and surgical procedure performed were collected. Prospectively collected nutritional scores were evaluated. Outcome measures included duration of surgery, length of ICU and total hospital stay, post-operative complications, and mortality indices. We performed multivariate Cox regression analysis to determine the contribution of various risk factors towards overall survival following emergency laparotomy.

Results

A total of 170 emergency laparotomies were performed. Compared to non-elderly patients, elderly patients had a significantly longer mean stay in hospital (31.5 vs. 18.6 days, p = 0.006) and mean stay in ICU (13.1 vs. 5.3 days, p = 0.003). More elderly patients suffered from post-laparotomy complications compared with non-elderly patients (65.8% vs. 37.4%, p < 0.001). 30-day mortality (31.5% vs. 8.8%, p = 0.019) and 1-year mortality (27.9% vs. 14.3%, p = 0.023) were higher in elderly patients compared with non-elderly patients. Interestingly, there was no statistically significant difference between elderly and non-elderly groups in both the global 3-MinNS as well as the global SGA nutritional scores. ASA status (HR 2.61, 95% CI 1.05–6.45, p = 0.038) was an independent risk factor for decreased survival following emergency laparotomy. Notably, while age ≥ 65 demonstrated a significant correlation with survival on univariate analysis (HR 1.03 (1.01–1.05), p = 0.003), this effect was lost following multivariate regression (HR 1.01 (0.453–2.23), p = 0.989).

Conclusion

Elderly patients suffer worse morbidity and mortality following emergency laparotomy. This is likely contributed by comorbidities resulting in higher ASA status.

  相似文献   
60.
ObjectivesTo investigate the effect of corneal stromal pocket irrigation after small-incision lenticule extraction (SMILE) on visual acuity, intraocular pressure (IOP), corneal parameters and complications after surgery.MethodsA total of 242 eyes of 121 patients undergoing SMILE were enrolled in this prospective controlled study, and it was designed for one eye to randomly undergo SMILE with balanced salt solution irrigation of the corneal stromal pocket, while the other eye was not. The uncorrected distance visual acuity (UDVA) and slit lamp examination were recorded at 1 hour, 1 day, 1 week, and 1 month. Postoperative corneal density, corneal biomechanical, corneal endothelial cell number, and anterior OCT images were compared at 1 day, 1 week, and 1 month.ResultsCompared with the nonirrigation group, the irrigation group showed significantly higher UDVA at 1 day postoperatively (P < 0.05), but there was no significant difference during the rest of the postoperative period (1 hour, 1 week, and 1 month). In addition, no significant differences were found in IOP, corneal density, corneal biomechanics, corneal endothelial cells, and corneal morphology. No visual decline or severe postoperative complications were found in the patients in this study.ConclusionsInterlamellar irrigation did not affect IOP, corneal parameters, morphology, complications, or UDVA at 1 hour, 1 week, and 1 month after the operation, but it may promote UDVA 1 day after the operation.Subject terms: Refractive errors, Outcomes research, Surgery  相似文献   
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