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991.
Xiang Li Chun-Hao Huang Francisco J. Snchez-Rivera Margaret C. Kennedy Darjus F. Tschaharganeh John P. Morris IV Antonella Montinaro Kevin P. O'Rourke Ana Banito John E. Wilkinson Chi-Chao Chen Yu-Jui Ho Lukas E. Dow Sha Tian Wei Luan Elisa de Stanchina Tinghu Zhang Nathanael S. Gray Henning Walczak Scott W. Lowe 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(17)
992.
目的 分析猪心血拌丹参及其他丹参炮制品中11个小分子活性成分及1个蛋白成分与抗脑缺血氧化损伤的相关性,明确猪心血拌丹参抗脑缺血氧化损伤的关键成分标志物。方法 采用高效液相色谱法(HPLC)同时测定丹参、猪心血拌丹参、猪血拌丹参、酒拌丹参、猪血清转铁蛋白(Tf)拌丹参5种饮片中11种活性成分含量;采用酶联免疫吸附测定法(ELISA)检测丹参不同炮制品中Tf的含量。构建斑马鱼缺血性脑卒中模型,考察丹参不同炮制品对脑缺血斑马鱼行为轨迹、转基因斑马鱼Tg(elavl3:eGFP)脑神经元损伤及脑组织中丙二醛(MDA)和超氧化物歧化酶(SOD)水平的影响;构建糖氧剥夺/复氧(OGD/R)诱导的小鼠海马神经细胞缺血缺氧模型,以乳酸脱氢酶(LDH)、活性氧(ROS)、MDA和SOD为评价指标,考察丹参不同炮制品对神经细胞氧化损伤的影响;通过主成分分析(PCA)、偏最小二乘判别法-判别分析(PLS-DA)及Spearman相关性分析对11个小分子活性成分及1个蛋白成分与药效指标进行分析,筛选猪心血拌丹参抗脑缺血氧化损伤的关键成分标志物。结果 与丹参比较,丹参各炮制品中水溶性、脂溶性成分含量均呈不同程度的升高,而丹酚酸A成分含量降低;与酒拌丹参比较,猪心血拌丹参、猪血拌丹参及Tf拌丹参中丹酚酸B、丹参素、迷迭香酸等成分含量均升高,而丹酚酸A含量降低。ELISA结果显示,猪心血拌丹参、猪血拌丹参及Tf拌丹参中均含有Tf蛋白,且三者含量差异无统计学意义。药效结果显示,丹参不同炮制品均能改善斑马鱼缺血性脑卒中后出现的行为缺陷、脑神经元损伤及氧化应激,且猪心血拌丹参组作用最明显。PCA结果显示,丹酚酸B、丹酚酸A、迷迭香酸、紫草酸、丹参素、咖啡酸、丹参酮ⅡA、隐丹参酮、丹参酮Ⅰ为丹参及其炮制品中的主要贡献成分。相关性分析结果显示,隐丹参酮、迷迭香酸、咖啡酸、二氢丹参酮Ⅰ、丹酚酸B、丹参酮ⅡA、丹参酮Ⅰ与斑马鱼脑组织中MDA水平呈负相关,紫草酸、原儿茶醛、迷迭香酸、二氢丹参酮Ⅰ、丹酚酸B、Tf与SOD水平呈正相关,迷迭香酸、咖啡酸、二氢丹参酮Ⅰ、丹酚酸B、丹参酮ⅡA、丹参酮Ⅰ、丹参素、Tf与斑马鱼脑神经元荧光强度呈正相关;紫草酸、原儿茶醛、迷迭香酸、二氢丹参酮Ⅰ、丹酚酸B、丹参素、Tf与HT22细胞中LDH、ROS、MDA水平呈负相关,与SOD水平呈正相关。结论 丹参及其不同炮制品抗脑缺血氧化损伤作用存在差异,其中以猪心血拌丹参改善氧化损伤作用最强,这可能与丹酚酸B、丹参素、迷迭香酸等成分的含量变化有关,可为明确该孟河医派特色炮制品抗脑缺血质量标志物及阐明其炮制机制提供依据。 相似文献
993.
目的:观察补阳还五汤超声导入治疗缺血性脑卒中后上肢运动功能障碍气虚血瘀证的临床疗效。
方法:选取60例缺血性脑卒中后上肢运动功能障碍气虚血瘀证患者,采用随机数字表法分为对照组与治疗组,
每组30例。对照组给予内科与常规康复治疗,治疗组在对照组基础上给予补阳还五汤超声导入治疗。2组均治
疗8周。比较2组痉挛程度、上肢运动功能、生活质量及表面肌电信号指标。结果:治疗4周、8周后,2组改
良Ashworth量表分级均较治疗前改善,差异均有统计学意义(P<0.05);治疗组改良Ashworth量表分级改善情
况均优于同期对照组,差异均有统计学意义(P<0.05)。组别和时间的交互作用对简式Fugl-Meyer运动功能评
定量表(FMA)、改良Barthel指数评定量表(MBI) 评分的影响均有统计学意义(P<0.05)。组别因素对FMA、
MBI评分的单独效应均有统计学意义(P<0.05)。时间因素对2组FMA、MBI评分的单独效应均有统计学意
义(P<0.05)。治疗4周后,2组FMA、MBI评分均较治疗前升高,差异均有统计学意义(P<0.05)。治疗8周
后,2组FMA、MBI评分均较治疗4周后升高,差异均有统计学意义(P<0.05)。治疗4周、8周后,治疗组
FMA、MBI评分均高于同期对照组,差异均有统计学意义(P<0.05)。治疗8周后,2组肱二头肌、肱三头肌
肌肉活动时的肌电均方根(RMS) 及积分肌电值(iEMG) 均较治疗前降低,治疗组上述4项上肢肌电信号指标
值均低于对照组,差异均有统计学意义(P<0.05)。结论:补阳还五汤超声导入治疗缺血性脑卒中后上肢运动
功能障碍气虚血瘀证疗效满意,能有效降低上肢肌张力,缓解肌痉挛症状,改善患者的日常生活能力和运动
功能。 相似文献
994.
Xiayu Xiang Chuanyi Liu Yanchun Zhang Wei Xiang Binxing Fang 《Asian Pacific journal of tropical medicine》2021,(9):417-428
Objective: To determine the most influential data features and to develop machine learning approaches that best predict hospital readmissions among patients with diabetes.Methods: In this retrospective cohort study, we surveyed patient statistics and performed feature analysis to identify the most influential data features associated with readmissions. Classification of all-cause, 30-day readmission outcomes were modeled using logistic regression, artificial neural network, and Easy Ensemble. F1 statistic, sensitivity, and positive predictive value were used to evaluate the model performance. Results: We identified 14 most influential data features(4 numeric features and 10 categorical features) and evaluated 3 machine learning models with numerous sampling methods(oversampling, undersampling, and hybrid techniques). The deep learning model offered no improvement over traditional models(logistic regression and Easy Ensemble) for predicting readmission, whereas the other two algorithms led to much smaller differences between the training and testing datasets.Conclusions: Machine learning approaches to record electronic health data offer a promising method for improving readmission prediction in patients with diabetes. But more work is needed to construct datasets with more clinical variables beyond the standard risk factors and to fine-tune and optimize machine learning models. 相似文献
995.
Jie LIU Xin-Xing FENG Yan-Feng DUAN Jun-Hao LIU Ce ZHANG Lin JIANG Lian-Jun XU Jian TIAN Xue-Yan ZHAO Yin ZHANG Kai SUN Bo XU Wei ZHAO Ru-Tai HUI Run-Lin GAO Ji-Zheng WANG Jin-Qing YUAN Xin HUANG Lei SONG 《老年心脏病学杂志》2022,19(5):367
BACKGROUNDThree-vessel disease (TVD) with a SYNergy between PCI with TAXus and cardiac surgery (SYNTAX) score of ≥ 23 is one of the most severe types of coronary artery disease. We aimed to take advantage of machine learning to help in decision-making and prognostic evaluation in such patients.METHODSWe analyzed 3786 patients who had TVD with a SYNTAX score of ≥ 23, had no history of previous revascularization, and underwent either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) after enrollment. The patients were randomly assigned to a training group and testing group. The C4.5 decision tree algorithm was applied in the training group, and all-cause death after a median follow-up of 6.6 years was regarded as the class label.RESULTSThe decision tree algorithm selected age and left ventricular end-diastolic diameter (LVEDD) as splitting features and divided the patients into three subgroups: subgroup 1 (age of ≤ 67 years and LVEDD of ≤ 53 mm), subgroup 2 (age of ≤ 67 years and LVEDD of > 53 mm), and subgroup 3 (age of > 67 years). PCI conferred a patient survival benefit over CABG in subgroup 2. There was no significant difference in the risk of all-cause death between PCI and CABG in subgroup 1 and subgroup 3 in both the training data and testing data. Among the total study population, the multivariable analysis revealed significant differences in the risk of all-cause death among patients in three subgroups.CONCLUSIONSThe combination of age and LVEDD identified by machine learning can contribute to decision-making and risk assessment of death in patients with severe TVD. The present results suggest that PCI is a better choice for young patients with severe TVD characterized by left ventricular dilation.Coronary artery disease (CAD) is the leading cause of death and disability worldwide.[1] Three-vessel disease (TVD) is the most severe form of CAD and is characterized by significant stenosis in all three major coronary arteries. The application of myocardial revascularization techniques, including coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI), has significantly improved the clinical outcomes of patients with severe CAD. CABG has traditionally been the standard therapy for complex coronary lesions, including TVD.[2] In recent years, with the advancements in PCI technology and the accumulation of operators’ experience, the incidence of periprocedural and long-term adverse events of PCI has substantially decreased, and PCI has been gradually applied in the treatment of TVD.[3,4] Current guidelines recommend use of the SYNergy between PCI with TAXus and cardiac surgery (SYNTAX) score and diabetes status to guide the revascularization strategy for patients with TVD.[5,6] Current practice guidelines do not recommend PCI for patients with TVD with a SYNTAX score of ≥ 23. However, using the SYNTAX score to guide clinical decision-making between PCI and CABG remains controversial, and its reasonability has been questioned since a newly published meta-analysis showed no significant association between the SYNTAX score and the comparative effectiveness of PCI and CABG.[7] Moreover, the SYNTAX score is a quantitative indicator of the anatomical complexity of TVD and does not include clinical variables that may have significant effects on the patient’s prognosis. Whether some patients with specific clinical characteristics can obtain a comparable or even greater survival benefit from PCI than from CABG is unclear. Moreover, risk assessment for patients with TVD after revascularization therapy remain challenging.[8–10]Machine learning has recently emerged as an important research method and has been successfully applied in many scientific fields, including clinical medicine.[11–13] The decision tree algorithm, a common approach in machine learning, can handle non-linearity, heterogeneous effects, and high-dimensional features and partition a trial population into subgroups characterized by multiple simultaneous characteristics.[14] In the present study involving a large cohort of patients with TVD with a SYNTAX score of ≥ 23, we employed a decision tree algorithm to generate specific subgroups, compared the long-term prognosis between patients who underwent PCI or CABG in each subgroup, and conducted a comparative analysis of the long-term prognosis between subgroups generated by machine learning. We evaluated whether machine learning can help in selecting the optimal revascularization method and assessing risk in patients with severe TVD. 相似文献
996.
脐血和新生儿外周血CD4+CD25+调节性T细胞的表型特征及意义 总被引:1,自引:0,他引:1
目的 探讨脐血和新生儿外周血中CD4 CD25 调节性T细胞的表型特征及其意义.方法以18份脐血和9份新生儿外周血为标本,细胞膜表面抗原采用单抗直接标记法,检测胞内抗原(CD152、FoxP3)时先标记膜表面抗原,固定破膜后再标记胞内抗原,应用多参数流式细胞仪进行检测和结果分析.结果脐血和新生儿外周血中的CD4 CD25 T细胞显示为独立的细胞群,脐血中该群细胞占CD4 T细胞比例为(9.26±2.43)%,新生儿外周血中的比例则为(9.35±2.30)%;在表型方面,大部分是CD45RA 的细胞,同时表达CD62L、胞浆内的CD152,也表达FoxP3,CD4 CD25 FoxP3 占CD4 T细胞比例为(1.92±0.28)%.结论 脐血和新生儿外周血中存在着一群单纯且水平较高的CD4 CD25 调节性T细胞,它们可能在发挥对母体非遗传性抗原的耐受及防止母体对胎儿的排斥反应中具有独特的作用. 相似文献
997.
目的 探讨在肾移植免疫诱导治疗中巴利昔单抗(舒莱)的有效性和安全性.方法随机选取69例肾移植受者,在常规三联免疫抑制方案的基础上,分别接受舒莱或ATG诱导治疗,对比观察两组的人/肾存活率、排斥反应以及包括感染在内的药物相关副作用的差异.结果接受舒莱的患者组药物相关副作用显著低于接受ATG的患者组(P<0.05),两组患者的人/肾存活率、急性排斥反应和肺部感染的发生率均无显著差异(P>0.05).移植物功能(移植后血肌酐水平及下降速度)在移植早期舒莱组优于ATG组,而长期随访结果显示两组之间无显著差异.结论 肾移植受者接受巴利昔单抗(舒莱)免疫诱导治疗是安全和有效的,与ATG诱导治疗方法比较具有更少的副作用. 相似文献
998.
目的 通过基因芯片分析发现人单核细胞THP-1氧化LDL的过程中二价金属转运蛋白1(Divalent metal transporter 1,DMT1)的mRNA表达水平显著升高.本实验通过RT-PCR和Western Blot来验证基因芯片的结果.方法用空白,LPS,LDL分别处理THP-1细胞,应用RT-PCR和Western Blot比较在LDL和LPS处理后THP-1细胞DMT-1的表达情况.结果 RT-PCR和Western Blot结果显示,在THP-1氧化LDL的过程中DMT1的表达显著升高.LDL和LPS相比,用LDL处理的THP-1细胞的DMT1的表达增加较LPS处理的明显.结论 RT-PCR和western blot证明了基因芯片的结果,在THP-1氧化LDL的过程中DMT1的表达显著升高,为临床心血管疾病的抗氧化治疗提供新的思路. 相似文献
999.
树突状细胞激活的肿瘤浸润淋巴细胞抗小鼠乳腺癌研究 总被引:1,自引:0,他引:1
目的 探讨C127细胞全细胞性抗原致敏的DC激活的TIL体外抗小鼠乳腺癌活性,并将C127细胞全细胞性抗原致敏的DC激活的TIL(C127-DC-TIL)过继免疫荷瘤小鼠,研究其对C127荷瘤小鼠免疫功能的影响及抑瘤作用.方法 从小鼠四肢长骨骨髓中获取DC,应用粒,巨噬细胞集落刺激因子(GM-CSF)、白介素-4(IL-4)和肿瘤全细胞性抗原致敏DC,然后用DC激活TIL,观察TIL在体外对C127细胞、MA782细胞和B16细胞的杀伤活性;检测应用C127-DC-TIL后荷瘤小鼠的脾淋巴细胞的NK、LAK、CTL活性、血清TNF活性、抑瘤作用以及瘤体病理改变,并与对照组相比较.结果 ①C127-DC-TIL具有很强的对C127细胞杀伤活性[杀伤率为(70.21±2.86)%],明显高于其对MA782和B16细胞的杀伤活性[杀伤率分别为(51.31±3.25)%,(31.41±2.65)%],也明显高于未经DC激活的TIL、C127-DC-脾淋巴细胞和未经DC激活的脾淋巴细胞对C127细胞杀伤活性[杀伤率分别为(48.30±2.97)%,(47.76±3.43)%和(17.23±2.56)%]和对MA782细胞杀伤活性[杀伤率分别为(38.52±2.87)%,(36.62±2.75)%和(18.07±2.40)%]以及对B16细胞杀伤活性[杀伤率分别为(25.38±2.63)%,(24.82±2.81)%和(17.34±2.81)%],同时B16细胞全细胞性抗原致敏的DC激活的TIL(B16-DC-TIL,TIL来源于C127瘤体)也可诱导相对较低的对B16细胞的特异性细胞杀伤活性.②C127-DC-TIL可明显诱导提高荷瘤小鼠脾淋巴细胞NK、LAK和CTL活性[活性分别为(32.21±1.24)%、(30.35±1.72)%和(37.43±1.54)%],并可检测到血清TNF水平明显上升[血清TNF水平为(38.41±1.77)U/ml],它们均达正常对照组水平,与未经DC激活的TIL组、C127-DC-脾淋巴细胞组、未经DC激活的脾淋巴细胞组、生理盐水组分别对应比较,差异均有显著性(P<0.01).该组瘤体内淋巴细胞浸润程度也高于对照组,其瘤体生长明显受到抑制.结论 ①C127-DC-TIL可产生很强的体外针对C127细胞的特异性杀伤活性.②C127-DC-TIL具有很强的特异性抗小鼠乳腺癌作用. 相似文献
1000.