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991.
Zhi Yu Wang Fu Qing Zeng Zhao Hui Zhu Guo Song Jiang Lei Lv Feng Wan Rui Dong Xing Yuan Xiao Shi An Xing 《Urologic oncology》2012,30(2):167-176
ObjectivesTo study the underlying alteration in the expression of epithelial markers involved in epithelial-mesenchymal transition (EMT), and elucidate the potential mechanism(s) for Tβ4-induced EMT-like phenotypic changes in bladder cancer cells.Materials and methodsAll tissue samples in this study were obtained from clinical patients of the Union Hospital of Tongji Medical College, and were confirmed by surgery and pathology. Of these, normal bladder tissues (control), primary urothelial carcinoma of different grades (Stage pTa, Stage pT3), bladder paracancerous tissues, accompanied with 2 bladder cancer cell lines (BIU-87 and T24), were divided into 6 groups. Quantitative RT-PCR, Western blotting, and immunohistochemical study of adhesion molecules Tβ4, ILK, E-cadherin, and β-catenin involved in EMT were carried out. A lentiviral gene transferring vector containing the RNA polymerase III-dependent U6 promoter to express short hairpin RNA (shRNA) directed against Tβ4 was also applied. In the present study, all agents were evaluated using commercial kits.ResultsA strong correlation between the expression levels of Tβ4, ILK, E-cadherin, and β-catenin was found in the bladder transitional cell carcinoma (TCC) patients. In the BIU-87 and T24 bladder cancer cells overexpressing Tβ4, which were accompanied by a loss of E-cadherin as well as a cytosolic accumulation of β-catenin, up-regulation of ILK was also revealed. The inhibition of the Tβ4 expression with lentiviral shRNA vector could raise EMT-like phenotypic changes, significantly depressed motility, and subsequent invasiveness of bladder cancer cells.ConclusionsOur results imply that the Tβ4 is likely to play a crucial role in EMT progression, and that inhibition of the Tβ4 expression or interactions with other genes should be novel therapeutic targets for bladder cancers with high invasive and metastatic potential. 相似文献
992.
Introduction
Inflammatory myofibroblastic tumor (IMT) is a rare low-grade malignant mesenchymal tumor, which can occur at any location, although the lung is the most commonly affected organ. It is extremely rare in the duodenum and only two cases have been reported previously. We report, to our knowledge, the first case of multiple neoplastic lesions.Case report
A 20-year-old male presented with the chief complaints of intermittent right epigastric pain, nausea and vomiting. Imaging examination, electronic gastroscopy and preoperative biopsy revealed undefined lesions in the duodenum. Pancreaticoduodenectomy was performed and diagnosis of multiple IMT was confirmed by pathological biopsy of the excised tumor. A satisfactory outcome was proved by the follow-up 1 year after curative operation.Conclusion
IMT can be diagnosed by histological examination and immunohistochemical test after surgical resection. Patients can benefit from radical resection with favorable prognosis. 相似文献993.
背景:关节软骨无血管分布,其营养来自关节液和软骨下骨,哪条营养通路对关节软骨更为重要是学者们争论的焦点。目的:研究软骨下营养对关节软骨的影响,并探讨软骨下营养与骨关节炎的关系。方法:45只5个月龄雄性新西兰大白兔,建立股骨滑车骨软骨缺损的动物模型,并随机分为3组:自体骨软骨块移植组(Control组,n=15);假手术组(Sham组,n=15),用环钻在股骨滑车钻取骨软骨块,将其置入管状PVC内,原位回植;阻断软骨下营养组(DNBM组,n=15),取出骨软骨后,将其置入帽状PVC内,原位回植。术后4周、8周、12周,每组5只(10膝),取出膝关节进行大体评分、组织学评分、软骨厚度测量、凋亡染色(TUNEL染色)。结果:与Control组相比,大体评分结果提示,DNBM组软骨无明显退变;组织学评分结果提示,术后12周时DNBM组软骨明显退变(P〈0.005);软骨厚度测量结果提示,术后8周、12周时DNBM组软骨厚度明显变小(P=0.00);TUNEL染色结果提示,术后8周、12周时DNBM组关节软骨细胞凋亡明显增加(P〈0.01)。结论:软骨下营养是软骨的重要营养来源,失去软骨下营养,软骨会逐渐发生退变。 相似文献
994.
Yang Gao Shixiong Tian Yanwei Sha Xiaomin Zha Huiru Cheng Anyong Wang Chunyu Liu Mingrong Lv Xiaoqing Ni Qiang Li Huan Wu Qing Tan Dongdong Tang Bing Song Ding Ding Jiangshan Cong Yuping Xu Ping Zhou Xiaojin He 《Reproductive biomedicine online》2021,42(5):963-972
Research questionMultiple morphological abnormalities of the flagella (MMAF) is characterized by excessive immotile spermatozoa with severe flagellar abnormalities in the ejaculate. Previous studies have reported a heterogeneous genetic profile associated with MMAF. What other genetic variants might explain the cause of MMAF?DesignWhole-exome sequencing was conducted in a cohort of 90 Chinese patients with MMAF. The pathogenicity of identified mutations was assessed through electron microscopy and immunofluorescent examinations.ResultsThree unrelated men with bi-allelic DNAH2 variants were identified. Sanger sequencing verified that the six novel variants originated from every parent. All these variants were located at the conserved domains of DNAH2 and predicted to be deleterious by bioinformatic tools. Haematoxylin and eosin staining and scanning electron microscopy revealed that spermatozoa harbouring DNAH2 variants displayed severely aberrant morphology mainly with absent and short flagella (≥78%). Moreover, transmission electron microscopy revealed the obvious absence of a central pair of microtubules and inner dynein arms in the spermatozoa with mutated DNAH2. Immunofluorescence data further validated these findings, showing reduced DNAH2 protein expression in the spermatozoa with DNAH2 variants, compared with normal spermatozoa. Intracytoplasmic sperm injection using spermatozoa from the three men with mutated DNAH2 resulted in blastocyst formation in all cases. Embryo transfer was carried out in two couples, both resulting in clinical pregnancy.ConclusionsThese experimental and clinical data suggest that bi-allelic DNAH2 variants might induce MMAF-associated asthenoteratozoospermia, which can be overcome through intracytoplasmic sperm injection. These findings contribute to the knowledge of the genetic landscape of asthenoteratozoospermia and clinical counselling of male infertility. 相似文献
995.
Wan Yu-Ting Liu Shan Zhao Shan-Ke Luo Yi-Yang Lv Ya-Su Qu Dan-Ni Liu Ming-Hui Li Yuan 《Journal of assisted reproduction and genetics》2021,38(4):809-824
Journal of Assisted Reproduction and Genetics - Granulosa cells (GCs) surrounding oocytes are crucial for follicular growth, oocyte development, ovulation, and luteinization under the dynamic... 相似文献
996.
997.
Introduction
Perimedullary arteriovenous fistula (AVF) has shunt on the spinal cord surface and it can be treated with surgery, or endovascular embolization. Intramedullary arteriovenous malformation (AVM) has its nidus in the cord and is difficult to treat either by surgery or endovascular technique. We report our experience with endovascular embolization in the treatment of perimedullary AVF and intramedullary AVM. 相似文献998.
三种电阻抗断层动态成像算法进行了比较研究。基于有限元仿真模型,对三种算法的图像分辨率、抗噪性能和运算速度分别进行了对比,结果表明,反投影算法具有良好的抗噪性能,牛顿一步重建法的图像分辨率最佳,灵敏度矩阵重建算法整体性能适中。 相似文献
999.
目的:在64排螺旋CT(Multidetector Computed Tomography,64-MDCT)冠状动脉CT成像(Computed Tomography Coronary Angiography,CTCA)扫描时采用优化的回顾性心电门控扫描,在保证图像质量的前提下,最大限度地降低辐射剂量。材料与方法:连续选取行64-MDCT CTCA检查的患者100例,将心率控制在65BPM以下,根据扫描方案将患者分为2组,每组均采用回顾性心电门控扫描,根据患者的体重指数(Body Mass Index,BMI)确定管电流及管电压。第1组曝光期相及最大毫安输出均设定为75%R-R间期。第2组曝光期相设定为75%R-R间期,最大毫安输出设定为70%-80%R-R间期。扫描结束后,对两组之间的图像质量、有效剂量(Effective Dose,ED)行统计学分析;P0.05为差异有统计学意义。结果:两组之间的图像质量无统计学意义,有效剂量有统计学意义。第1组的ED值比第2组降低了20%。结论:优化的回顾性心电门控扫描可以进一步降低辐射剂量。 相似文献
1000.
目的研究腹膜初始转运功能与年龄、原发病、病程、净超滤量等的关系,阐述腹膜初始转运功能的流行病学特点。方法收集在泰安市中心医院泌尿内一科进行腹膜透析置管的患者48例,采用logistic回归法分析原发病、年龄、病程与腹膜初始转运功能的关系。结果对受试患者腹膜初始转运功能的相关影响因素进行单因素有序反应变量Logistic回归分析显示腹膜初始转运功能与年龄、病程有关系(P<0.05)。将有统计学意义的相关影响因素进行多因素有序反应变量Logistic逐步回归分析,表明病程与腹膜初始转运功能有关系(P<0.05)。结论随年龄增大、病程延长,腹膜初始转运功能转为低转运与高转运的机会有增加的趋势。原发病为糖尿病肾病者腹膜初始转运倾向于高转运;原发病为高血压肾损害、慢性肾炎者腹膜初始转运倾向于平均转运。 相似文献