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目的 探讨我国弓形虫Chinese 1优势基因型感染对宿主脑组织铁代谢及脑损伤的影响。方法 将20只C57BL/6(体质量15~17 g)小鼠随机分为对照组和感染组,每组10只。感染组每只小鼠腹腔注射4 000个弓形虫Chinese 1优势基因型TgCtwh3虫株速殖子,对照组小鼠注射等量无菌PBS,饲养6 d后处死小鼠并取其脑组织。采用电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry, ICP⁃MS)检测小鼠脑组织铁元素水平;采用RNA芯片检测两组小鼠脑组织差异基因数目并对功能基因表达情况进行基因本体论(Gene Ontology, GO)功能富集;采用实时荧光定量PCR(fluorescent quantitative real⁃time PCR, qPCR)技术检测小鼠脑组织中弓形虫表面抗原1(Toxoplasma gondii surface antigen 1,TgSAG1)基因及部分锌铁调控蛋白(Zrt⁃ and Irt⁃like protein, ZIP)家族mRNA表达水平;采用光镜和电镜观察小鼠脑组织海马齿轮回(dentate gyrus, DG)超微结构;采用Western blotting检测谷胱甘肽过氧化物酶4(glutathione peroxidase 4, GPx4)蛋白表达水平;采用硫代巴比妥酸(TBA)法检测丙二醛(malondialdehyde, MDA)水平;采用免疫组化检测血管内皮生长因子(vascular endothelial growth factor, VEGF)蛋白表达光密度(optical density, OD)值。结果 光镜下可见感染组小鼠脑组织海马DG区细胞坏死,电镜下见感染组小鼠脑组织海马区出现胞质空泡化、核皱缩坏死、线粒体嵴断裂消融、自噬小体增加等超微结构变化。与对照组相比,感染组小鼠脑组织中铁元素水平上调[(32.92 ± 0.90) µg/g vs.(37.72 ± 1.10) µg/g;t = 3.397, P < 0.01];RNA芯片检测感染组小鼠脑组织发现721个基因上调、276个基因下调,差异表达基因在金属离子结合能力上有明显富集。与对照组相比,感染组小鼠脑组织金属元素转运体ZIP2 mRNA表达水平上调(t = 8.659,P < 0.05)、GPx4表达下降[(1.046 ± 0.025) vs. (0.720 ± 0.101);t = 3.129,P < 0.01])、MDA水平升高[(4.37 ± 0.33) nmol/mgprot vs.(5.93 ± 0.54) nmol/mgprot;t = 2.451,P < 0.05)]、VEGF蛋白平均OD值上调[(0.348 3 ± 0.017 8) vs. (0.490 6 ± 0.010 5);t = 6.641,P < 0.01]。结论 Chinese 1优势基因型弓形虫感染后,小鼠脑组织中铁元素蓄积、抗氧化能力下调、氧化应激水平升高,提示弓形虫感染可影响宿主脑组织铁代谢而导致脑损伤。  相似文献   
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背景 广泛性焦虑障碍(GAD)是常见的慢性精神疾病,常伴有不同程度的认知功能损害,严重影响患者的生活质量及社会功能。 目的 比较GAD住院患者与健康对照者认知功能的差异。 方法 选取2018年8月至2020年1月在南方医科大学南方医院住院治疗的GAD患者为GAD组(n=30),同期通过广告在南方医科大学南方医院住院患者陪护人员中招募年龄、性别相匹配的健康志愿者为健康对照组(n=30)。使用汉密尔顿焦虑量表(HAMA)、汉密尔顿抑郁量表(HAMD)和Beck自杀意念量表中文版(BSI-CV)进行心理测评,采用精神运动警觉性任务(PVT)、Go/No-go联想任务、N-back任务分别评估认知功能的注意、抑制及工作记忆功能。比较两组一般情况、量表测评总分及认知功能差异,进一步采用多因素Logistic回归分析探究GAD住院患者和健康对照者的认知功能差异。 结果 GAD组HAMA、HAMD总分和最严重情况时BSI-CV总分及最严重情况时存在自杀意念者所占比例高于健康对照组(P<0.05)。N-back任务:GAD组1-back击中目标率(NBACK1a)、2-back击中目标率(NBACK2a)低于健康对照组,1-back击中目标的平均反应时(NBACK1b)长于健康对照组(P<0.05)。多因素Logistic回归分析结果显示,NBACK1a〔OR=0.946,95%CI(0.898,0.997),P=0.038〕、NBACK1b〔OR=1.007,95%CI(1.000,1.014),P=0.042〕是GAD的影响因素。 结论 与健康对照者相比,GAD住院患者的工作记忆较差,需要临床关注。  相似文献   
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Hepatitis E virus (HEV) is the most common cause of acute liver failure (LF) and one of the most common factors causing acute injury in acute-on-chronic LF (ACLF). When HEV-related LF occurs, a series of changes take place in both the intrahepatic environment and extrahepatic microenvironment. The changed types and distribution of immune cells (infiltrating macrophages and increased lymphocytes) in liver tissue, as well the increased proinflammatory cytokines and chemokines in the blood, indicate that the occurrence and progression of HEV-related LF are closely related to immune imbalance. The clinical features and immune reaction in the body during HEV-related acute LF (ALF) and ACLF are complicated. This review highlights recent progress in elucidating the clinical manifestations of HEV-associated ALF and ACLF and discusses the corresponding systemic immune changes and possible regulatory mechanisms.  相似文献   
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Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  相似文献   
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BACKGROUNDDue to the special clinical features and biologic characteristics of adolescent and young adult (AYA) cancers, AYA cancers are different from cancers in children and elderly individuals. However, there are few reports on AYA hepatocellular carcinoma (HCC).AIMTo investigate the overall survival (OS) of AYA (15-39 years) and elderly (40-74 years) patients with HCC.METHODSThe data of all the HCC cases were extracted from the Surveillance, Epidemiology, and End Results database from 2004 to 2015 and were then divided into two groups based on age: AYA group (15-39 years) and older group (40-74 years). Kaplan-Meier curves and log-rank tests were used to compare the OS of the two groups. Propensity score matching (PSM) was employed to analyze the OS difference between the two groups. The Cox proportional hazards regression model was used to perform multivariate analysis to explore the risk factors for OS of HCC patients.RESULTSCompared to elderly cancer patients, AYA patients with HCC had a worse Surveillance, Epidemiology, and End Results stage, including the distant stage (22.1% vs 15.4%, P < 0.001), and a more advanced American Joint Committee on Cancer (AJCC) stage, including AJCC III and IV (49.2% vs 38.3%, P < 0.001), and were more likely to receive surgery (64.5% vs 47.5%, P < 0.001). Before PSM, the AYA group had a longer survival in months (median: 20.00, interquartile range [IQR]: 5.00-62.50) than the older group (median: 15.00, IQR: 4.00-40.00) (P < 0.001). After PSM, the AYA group still had a longer survival in months (median: 21.00, IQR: 5.00-64.50) than the older group (median: 18.00, IQR: 6.00-53.00) (P < 0.001). The Cox proportional hazards regression model showed that advanced age (hazard ratio [HR] = 1.405, 95%CI: 1.218-1.621, P < 0.001) was a risk factor for OS of HCC patients. In the subgroup analysis, the Cox proportional hazards regression model showed that in AJCC I/II HCC patients, advanced age (HR = 1.749, 95%CI: 1.352-2.263, P < 0.001) was a risk factor for OS, while it was not a risk factor in AJCC III/IV HCC patients (HR = 1.186, 95%CI: 0.997-1.410, P = 0.054) before PSM. After PSM, advanced age (HR = 1.891, 95%CI: 1.356-2.637, P < 0.001) was still a risk factor for OS in AJCC I/II HCC patients, but was not a risk factor for OS in AJCC III/IV HCC patients (HR = 1.192, 95%CI: 0.934-1.521, P = 0.157) after PSM.CONCLUSIONAYA patients with HCC have different clinical characteristics from older adults. In different AJCC stages, the two groups of patients have different OS: In AJCC I/II HCC patients, advanced age is a risk factor for OS, but it is not a risk factor for OS in the AJCC III/IV HCC patient group.  相似文献   
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目的从细胞因子角度,探究人参败毒散多成分、多靶点、多途径抗新型冠状病毒肺炎(COVID-19)的作用机制。方法应用中药系统药理分析平台(TCMSP)收集人参败毒散中活性化合物,结合药物靶点数据库收集细胞因子风暴相关靶点,利用Cytoscape构建"药材-化合物-疾病靶点"网络。通过String和DAVID数据库对靶点的互作网络、GO功能和KEGG通路进行分析。结果人参败毒散"药材-活性化合物-疾病靶点"网络包括10种药材,211个活性成分和151个疾病靶点。互作网络发现人参败毒散抑制细胞因子风暴治疗COVID-19的靶点可能包含STAT3、MAPK1、NFκB1、PIK3CA、MAPK3、TNF、CXCR4、VEGFA、IL-6、IL-2等。GO功能分析发现上述靶点在生物功能方面涉及趋化性、类固醇代谢过程等;在分子功能方面涉及血红素结合、铁离子结合、氧结合等;在细胞组成方面涉及细胞表面、细胞膜等。KEGG通路富集发现上述靶点参与查加斯病通路、HIF-1信号通路、肿瘤坏死因子信号通路等的调控。结论人参败毒散可能通过调节趋化性细胞因子,增加血氧饱和度,抑制STAT、MAPK、NFκB、PIK3K、IL-6等炎症相关信号通路,实现多成分-多靶点-多途径抑制细胞因子风暴形成的抗COVID-19作用。  相似文献   
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目的探讨早期卧位踏车训练在下肢重度烧伤患者功能康复中的临床效果。方法2016年10月至2017年12月,下肢重度烧伤患者30例分为对照组和观察组,各15例。对照组采用常规综合康复,观察组此基础上增加早期卧位踏车训练。入院时和住院治疗6周后,采用焦虑自评量表(SAS)、抑郁自评量表(SDS)、疼痛数字评分法(NRS)、Berg平衡量表(BBS)和6分钟步行测试进行评定。结果治疗后,两组SAS、SDS、NRS评分均明显降低(t>3.636,P<0.01),观察组低于对照组(t>2.319,P<0.05);观察组BBS评分和6分钟步行距离高于对照组(t>2.541,P<0.05)。结论早期卧位踏车训练对下肢重度烧伤患者功能恢复有一定促进作用。  相似文献   
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