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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
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Journal of Behavioral Medicine - Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses... 相似文献
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Weina Cheng Yazhi Wang Jingxian Liu Xiaofei Li Ming Yu Cancan Duan Liu Liu Jianyong Zhang 《Journal of applied toxicology : JAT》2022,42(6):970-980
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
4.
Feng Song Li Ruipiao Wang Zhiying 《Odontology / the Society of the Nippon Dental University》2022,110(3):508-522
Odontology - To investigate the characterization and function of a novel porous osteogenic material (PLLA / DDM) containing polylactic acid and demineralized dentin matrix. The surface morphology... 相似文献
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Huang Liyan Li Wei Li Yi Song Chaoyuan Wang Pin Wang Hongchun Sun Xiulian 《Neurogenetics》2020,21(1):39-49
neurogenetics - Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common monogenic disease leading to stroke and vascular dementia.... 相似文献
7.
Jiao-Tian Xu Yuan Qian Wei Wang Xiao-Xiang Chen Yang Li Yu Li Zhi-Yong Yang Xiao-Bin Song Di Lu Xing-Li Deng 《中国神经再生研究》2020,(1):112-119
Previous studies have shown that neural stem cell transplantation has the potential to treat Parkinson’s disease,but its specific mechanism of action is still unclear.Stromal cell-derived factor-1 and its receptor,chemokine receptor 4(CXCR4),are important regulators of cell migration.We speculated that the CXCR4/stromal cell-derived factor 1 axis may be involved in the therapeutic effect of neural stem cell transplantation in the treatment of Parkinson’s disease.A Parkinson’s disease rat model was injected with 6-hydroxydopamine via the right ascending nigrostriatal dopaminergic pathway,and then treated with 5μL of neural stem cell suspension(1.5×104/L)in the right substantia nigra.Rats were intraperitoneally injected once daily for 3 days with 1.25 mL/kg of the CXCR4 antagonist AMD3100 to observe changes after neural stem cell transplantation.Parkinson-like behavior in rats was detected using apomorphine-induced rotation.Immunofluorescence staining was used to determine the immunoreactivity of tyrosine hydroxylase,CXCR4,and stromal cell-derived factor-1 in the brain.Using quantitative real-time polymerase chain reaction,the mRNA expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra were measured.In addition,western blot assays were performed to analyze the protein expression of stromal cell-derived factor-1 and CXCR4.Our results demonstrated that neural stem cell transplantation noticeably reduced apomorphine-induced rotation,increased the mRNA and protein expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra,and enhanced the immunoreactivity of tyrosine hydroxylase,CXCR4,and stromal cell-derived factor-1 in the brain.Injection of AMD3100 inhibited the aforementioned effects.These findings suggest that the stromal cell-derived factor-1/CXCR4 axis may play a significant role in the therapeutic effect of neural stem cell transplantation in a rat model of Parkinson’s disease.This study was approved by the Animal Care and Use Committee of Kunming Medical University,China(approval No.SYXKK2015-0002)on April 1,2014. 相似文献
8.
Wang-Shu Zhu Si-Ya Shi Ze-Hong Yang Chao Song Jun Shen 《World journal of gastroenterology : WJG》2020,26(11):1208-1220
BACKGROUND Postoperative liver failure is the most severe complication in cirrhotic patients with hepatocellular carcinoma(HCC) after major hepatectomy. Current available clinical indexes predicting postoperative residual liver function are not sufficiently accurate.AIM To determine a radiomics model based on preoperative gadoxetic acid-enhanced magnetic resonance imaging for predicting liver failure in cirrhotic patients with HCC after major hepatectomy.METHODS For this retrospective study, a radiomics-based model was developed based on preoperative hepatobiliary phase gadoxetic acid-enhanced magnetic resonance images in 101 patients with HCC between June 2012 and June 2018. Sixty-one radiomic features were extracted from hepatobiliary phase images and selected by the least absolute shrinkage and selection operator method to construct a radiomics signature. A clinical prediction model, and radiomics-based model incorporating significant clinical indexes and radiomics signature were built using multivariable logistic regression analysis. The integrated radiomics-based model was presented as a radiomics nomogram. The performances of clinical prediction model, radiomics signature, and radiomics-based model for predicting post-operative liver failure were determined using receiver operating characteristics curve, calibration curve, and decision curve analyses.RESULTS Five radiomics features from hepatobiliary phase images were selected to construct the radiomics signature. The clinical prediction model, radiomics signature, and radiomics-based model incorporating indocyanine green clearance rate at 15 min and radiomics signature showed favorable performance for predicting postoperative liver failure(area under the curve: 0.809-0.894). The radiomics-based model achieved the highest performance for predicting liver failure(area under the curve: 0.894; 95%CI: 0.823-0.964). The integrated discrimination improvement analysis showed a significant improvement in the accuracy of liver failure prediction when radiomics signature was added to the clinical prediction model(integrated discrimination improvement = 0.117, P =0.002). The calibration curve and an insignificant Hosmer-Lemeshow test statistic(P = 0.841) demonstrated good calibration of the radiomics-based model. The decision curve analysis showed that patients would benefit more from a radiomics-based prediction model than from a clinical prediction model and radiomics signature alone.CONCLUSION A radiomics-based model of preoperative gadoxetic acid–enhanced MRI can be used to predict liver failure in cirrhotic patients with HCC after major hepatectomy. 相似文献
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目的探讨神经内镜辅助下经鼻蝶入路切除鞍区肿瘤的方法和优势。方法回顾性分析30例鞍区肿瘤病人的临床资料,垂体腺瘤26例(其中无功能垂体腺瘤6例、泌乳素瘤16例、垂体生长激素腺瘤4例),拉克囊肿1例,胆脂瘤1例,脑膜瘤1例,颅咽管瘤1例。采用神经内镜辅助下经鼻蝶入路手术切除肿瘤。结果肿瘤全切27例,部分切除3例。术后3例发生脑脊液鼻漏,经腰大池持续引流后痊愈。无死亡病例。随访3~6个月,病人恢复良好。结论在神经内镜辅助下经鼻蝶入路治疗鞍区肿瘤,较单纯的显微镜手术治疗创伤更小,肿瘤全切率更高。 相似文献