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1.
目的探讨脊髓小脑共济失调2型(SCA2)致病基因ATXN2异常等位基因中间重复个体的表型和分子遗传学特点。方法针对2005—2018年中日友好医院神经科运动障碍与神经遗传病研究中心收集的1383个常染色体显性遗传共济失调家系的先证者和部分家系成员,采用荧光标记毛细管电泳片段分析方法进行动态突变检测,对携带ATXN2基因中间重复的个体进行临床表型和遗传特征分析。结果共检出163个家系(包含先证者和家系成员共203人)携带异常扩展的ATXN2基因CAG重复序列,其中93个家系中有107例的异常扩展等位基因重复次数在29~34次之间。在其中的20个亲子对中,父系遗传16个,异常等位基因的代间扩展增加0~28次,母系遗传4个,异常等位基因的代间扩展增加0~4次。结论对于临床拟诊SCA2家系患者,需对其亲代或成年子代个体进行ATXN2基因检测,以免漏诊。动态突变基因检测有助于识别中间重复的个体,对明确家系致病基因和遗传咨询至关重要。  相似文献   
2.
Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague–Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite–gene–enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity.  相似文献   
3.
目的探究罗伊氏乳杆菌DSM 17938在治疗轮状病毒感染肠炎患儿中的疗效及对免疫功能、肠道菌群的影响。方法收集于2018年2月-2019年2月在阳光融和医院进行诊治的轮状病毒感染肠炎患儿126例,随机分为试验组(63例)和对照组(63例)。对照组给予常规补液治疗及蒙脱石散和枯草杆菌二联活菌口服治疗,试验组采用常规补液治疗及蒙脱石散和罗伊氏乳杆菌DSM 17938辅助治疗。观察两组患儿的腹泻改善情况,并分析对免疫功能(IgG、IgA、CD4^+/CD8^+水平)及肠道菌群失调的影响。结果在治疗72 h后,试验组患儿的治疗总有效率为92.06%,高于对照组的74.60%(P=0.009);且治疗后两组患儿的IgG、IgA、CD4^+/CD8^+水平均较治疗前有升高(P<0.05),且试验组水平高于对照组(P<0.05)。对患儿肠道菌群进行分析,在治疗1周后,试验组患儿肠道菌群失调程度低于对照组,且试验组的肠道菌群正常比例高于对照组(P<0.05)。结论罗伊氏乳杆菌DSM 17938对于辅助治疗轮状病毒感染肠炎患儿具有良好的疗效,能够提高患儿免疫力,改善肠道菌群失调,减轻患儿腹泻症状,具有一定的临床应用价值。  相似文献   
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目的 基于基因组Survey分析对刺果甘草Glycyrrhiza pallidiflora Maxim.基因组大小和杂合率进行估计,并通过叶绿体基因组序列特征对其在甘草属Glycyrrhiza L.中的系统发育位置进行研究。方法 使用二代测序技术对刺果甘草进行测序,采用K-mer方法对测序reads进行分析,估算刺果甘草基因组大小和杂合率,使用生物信息学方法进行叶绿体基因组组装、注释和系统发育分析。结果 Survey分析结果显示其基因组大小约为577.82 Mb,杂合度约为0.31%,重复序列比例约为53.72%。叶绿体基因组长度为127,267 bp,不具有典型的四分体结构,总GC含量为34.32%,包含110个基因,其中76个蛋白质编码基因,30个tRNA基因和4个rRNA基因。系统发育分析表明,刺果甘草与圆果甘草G. squamulosa Franch.亲缘较接近。结论 刺果甘草存在低杂合和重复序列较多的特点,为了更好地对全基因组进行序列拼接和组装,可尝试采用三代测序结合二代测序的分析策略进行基因组组装;刺果甘草叶绿体全基因组比对和系统发育分析,为后续开展甘草属遗传多样性研究和分子鉴定标记筛选提供了重要依据。  相似文献   
6.
植物药对结肠癌具有良好的防治作用。姜黄素、多糖(苹果多糖、香菇多糖)、皂苷(重楼皂苷、人参皂苷)、白藜芦醇、槲皮素等植物药可通过不同信号通路抑制结肠癌细胞的增殖,促进细胞凋亡。此外,植物药还具有抗炎、抗氧化、抗血管生成、减轻化疗药物不良反应、逆转肿瘤细胞耐药等作用。了解植物药对结肠癌的防治作用及其可能的作用机制,能为结肠癌的临床防治提供更多的理论依据及治疗思路。  相似文献   
7.
Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition represents the mechanism of action of Deferoxamine on spinal cord injury recovery. A rat model of Deferoxamine at thoracic 10 segment was established using a modified Allen's method. Ninety 8-week-old female Wistar rats were used. Rats in the Deferoxamine group were intraperitoneally injected with 100 mg/kg Deferoxamine 30 minutes before injury. Simultaneously, the Sham and Deferoxamine groups served as controls. Drug administration was conducted for 7 consecutive days. The results were as follows:(1) Electron microscopy revealed shrunken mitochondria in the spinal cord injury group.(2) The Basso, Beattie and Bresnahan locomotor rating score showed that recovery of the hindlimb was remarkably better in the Deferoxamine group than in the spinal cord injury group.(3) The iron concentration was lower in the Deferoxamine group than in the spinal cord injury group after injury.(4) Western blot assay revealed that, compared with the spinal cord injury group, GPX4, xCT, and glutathione expression was markedly increased in the Deferoxamine group.(5) Real-time polymerase chain reaction revealed that, compared with the Deferoxamine group, mRNA levels of ferroptosis-related genes Acyl-CoA synthetase family member 2(ACSF2) and iron-responsive element-binding protein 2(IREB2) were up-regulated in the Deferoxamine group.(6) Deferoxamine increased survival of neurons and inhibited gliosis. These findings confirm that Deferoxamine can repair spinal cord injury by inhibiting ferroptosis. Targeting ferroptosis is therefore a promising therapeutic approach for spinal cord injury.  相似文献   
8.
The purpose of this meta-analysis is to compare the relative merits among laparoscopic-assisted operations and laparotomy operations for patients with Hirschsprung disease.PubMed, Web of Science, and Wanfang databases were searched for the related articles. We analyzed dichotomous variables by estimating odds ratios (ORs) with their 95% confidence intervals (CIs) and continuous variables using the weighted mean difference (WMD) with the 95% CI. The random-effects model (REM) was used to combine the results. The outcome measures included operating time (OT), estimated blood loss (EBL), length of hospital stay (LOHS), mean first bowel movement (MFBM), and number of complications.Sixteen articles were included in the meta-analysis. These studies involved a total of 774 patients, 396 of whom underwent laparoscopic-assisted operations and 378 of whom underwent laparotomy operations. The EBL (WMD = −1.48, 95% CI = −1.82, −1.13), LOHS (WMD = −0.67, 95% CI = −0.86, −0.49), MFBM (WMD = −0.83, 95% CI = −1.05, −0.61), and number of complications (OR = 0.60, 95% CI = 0.40, 0.89) were significantly lower in laparoscopic-assisted operations than in laparotomy operations. The OT (WMD = 0.12, 95% CI = −0.05, 0.28) showed no significant differences between laparoscopic-assisted operations and laparotomy operations.Compared with laparotomy operations, laparoscopic-assisted operations are generally safer and more reliable for patients with Hirschsprung disease.  相似文献   
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10.
目的探讨CT扫描在胸膜外孤立性纤维瘤(E-SFT)中的诊断价值。方法回顾性分析2015年4月至2018年4月于我院接受手术治疗的90例E-SFT患者术前CT检查影像资料和术后病理、免疫组织化学资料,评估CT检查在E-SFT诊断中的应用价值。结果 90例E-SFT患者均为单发肿瘤,免疫组织化学及病理学检查示良性80例,恶性10例;CT检查结果为良性72例,平扫表现为圆形或类圆形软组织密度影,密度不均匀,大部分边缘清晰,增强扫描表现为均匀强化;恶性18例,平扫示肿瘤体积较大,边界不清,密度不均,可见大片不规则低密度区,增强扫描瘤体强化不均匀,低密度区无明显强化;CT诊断的敏感度、准确度、特异性阳性率、阴性率分别为60%(6/10)、82%(74/90)、85%(68/80)、33%(6/18)、94%(68/72)。结论 E-SFT的CT检查影像图像具有一定的特征性,尤其是增强扫描有助于评估纤维瘤的良恶性,可将其作为术前诊断及术后复查评估的有效依据用于临床诊疗工作中。  相似文献   
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