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971.
BACKGROUND: The non-specific immune suppression method is generally used for treatment of systemic lupus erythematosus, but poor prognosis, such as infection and high recurrence rate, exists.
OBJECTIVE: To evaluate the therapeutic effect of bone marrow mesenchymal stem cell transplantation on systemic lupus erythematosus in mice.
METHODS: Sixteen mice with systemic lupus erythematosus were equivalently randomized into control and experimental groups, or then subjected to passage 3 bone marrow mesenchymal stem cell transplantation or the equal volume of normal saline via the tail vein, respectively. Mouse urine samples were collected to detect urine protein levels by Bradford method. Blood samples from the tip of the mouse tail were extracted to detect serum anti-ds-DNS antibody concentration by radioimmunoassay. Mouse kidney tissues were taken and observed pathohistologically through hematoxylin-eosin staining and immunohistochemistry staining under microscope. Flow cytometry was used to detect the expression of CD4+CD25+T cells in the inner canthus blood, fresh spleen and thymus.
RESULTS AND CONCLUSION: Within 10 weeks after cell transplantation, the urine protein levels in the two groups were gradually increased, and the rising velocity was higher in the control group than in the experimental group. From the 4th to 10th week, the urine protein levels in the experimental group were significantly lower than those in the control group (P < 0.05). In the control group, lymphocyte infiltration was visible in the kidney tissues with a few of plasmocytes, and pathological findings showed the mice presented with interstitial nephritis; in the experimental group, the mice had no pathological changes in the kidney. In the two groups, immune complexes were found in the mesangial area, which showed a patch-like distribution in the control group and a punctate distribution in the experimental group; the relative proportion of the occupied area in the experimental group was significantly lower than that in the control group. The expression level of CD4+CD25+T cells in the blood and thymus were significantly higher in the experimental group than the control group (P < 0.05), and the expression level of CD4+CD25+T cells in the spleen was slightly higher in the experimental group than the control group with no significant difference (P > 0.05). The serum anti-ds-DNA antibody concentration in the experimental group was significantly lower than that in the control group (P < 0.05). Taken together, bone marrow mesenchymal stem cell transplantation can improve the pathological damage in systemic lupus erythematosus mice, and has a certain therapeutic effect on systemic lupus erythematosus.
相似文献
972.
BACKGROUND:Previous studies have demonstrated that the electrophysiological stability and ventricular fibrillation threshold after myocardial infarction in rats are significantly improved in the mid-term of cardiac stem cell transplantation, but relative regulatory mechanism and pathway remain unclear.
OBJECTIVE:To explore the relative molecular regulatory mechanism of cardiac stem cells improving the electrophysiological stability and ventricular fibrillation threshold after myocardial infarction in rats.
METHODS:Myocardial infarction was induced in 20 Sprague-Dawley rats by ligation of the left anterior descending coronary, which were then randomized into two groups (n=10 per group) and were subjected to the injection of cardiac stem cells labeled with PKH26 in phosphate buffer solution (cardiac stem cell group) or the same amount of phosphate buffer solution (PBS) alone (PBS group) into the local infarct zone at 2 weeks after modeling, respectively. Six weeks later, relevant signaling molecules involved in the ANGII/AT1R/TGF-β1/SMAD/Cx43 pathway were all examined in myocardial tissues of the left ventricle and harvested blood samples.
RESULTS AND CONCLUSION:Compared with the PBS group, expressions of connexin 43 in different zones of the left ventricle were significantly increased in the cardiac stem cell group (P < 0.01); there was a significant reduction of the angiotensin II level in plasma and different regions of the left ventricular (P < 0.05; P < 0.01). Furthermore, in the cardiac stem cell group, expressions of angiotensin II type I receptor, transforming growth factor-β1, SMAD2 and SMAD3 were significantly decreased (P < 0.01). Whereas SMAD7 was significantly elevated (P < 0.05) in different areas of the left ventricle compared with the phosphate buffer solution group. These findings suggest that the cardiac stem cell transplantation can improve the electrophysiological stability and ventricular fibrillation threshold after myocardial infarction by enhancing the expression of connexin 43 via ANGII/AT1R/TGF-beta1/SMAD/CX43 signaling pathway. 相似文献
973.
Association of IMMP2L deletions with autism spectrum disorder: A trio family study and meta‐analysis 下载免费PDF全文
Yanqing Zhang Mehdi Zarrei Winnie Tong Rui Dong Ying Wang Haiyan Zhang Xiaomeng Yang Jeffrey R. MacDonald Mohammed Uddin Stephen W. Scherer Zhongtao Gai 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2018,177(1):93-100
IMMP2L, the gene encoding the inner mitochondrial membrane peptidase subunit 2‐like protein, has been reported as a candidate gene for Tourette syndrome, autism spectrum disorder (ASD) and additional neurodevelopmental disorders. Here we genotyped 100 trio families with an index proband with autism spectrum disorder in Han Chinese population and found three cases with rare exonic IMMP2L deletions. We have conducted a comprehensive meta‐analysis to quantify the association of IMMP2L deletions with ASD using 5,568 cases and 10,279 controls. While the IMMP2L deletions carried non‐recurrent breakpoints, in contrast to previous reports, our meta‐analysis found no evidence of association (P > 0.05) between IMMP2L deletions and ASD. We also observed common exonic deletions impacting IMMP2L in a separate control (5,971 samples) cohort where subjects were screened for psychiatric conditions. This is the first systematic review and meta‐analysis regarding the effect of IMMP2L deletions on ASD, but further investigations in different populations, especially Chinese population may be still needed to confirm our results. 相似文献
974.
Aiming Wu Jie Wang Hong Chang Yizhou Zhao Yan Zhang Yingqiu Mao Lixia Lou Yonghong Gao Dongmei Zhang Tong Li Tao Yang Lei Wang Cuiling Feng Mingjing Zhao 《Anatomical record (Hoboken, N.J. : 2007)》2018,301(7):1216-1223
The rat carotid artery balloon injury model was used to prove the activation and migration of adventitial fibroblasts. We found that at day 7 after injury, adventitial fibroblasts proliferated, transformed into myofibroblasts under transmission electron microscopy in the model group. Simultaneously, we proved that the adventitial cells migrated to the media and intima on seventh day after injury by directly labeled the adventitial cells by the in vivo gene transfer technique. Moreover, we captured the precise moment when the adventitial fibroblasts migrated from the adventitia to the media through the external elastic plate under transmission electron microscope. This study provides direct evidences that adventitial fibroblasts activate and migrate to the media and intima, then actively take part in revascularization. Anat Rec, 301:1216–1223, 2018. © 2018 Wiley Periodicals, Inc. 相似文献
975.
目的:对华支睾吸虫(Clonorchis sinensis, Cs)成虫酸性磷酸酶 (acid phosphatase, AP)进行克隆、表达、生物学特征分析、组织定位及膜抗原/排泄分泌抗原鉴定。方法:对CsAP进行生物信息学、分子生物学、免疫组化及明胶酶谱分析。结果:从Cs cDNA文库中筛选出编码AP新基因,全长1 410 bp,重组并由大肠杆菌表达、纯化,得到分子量为55 kD的重组蛋白CsAP。Western blotting分析表明,CsAP既是膜抗原又是分泌排泄抗原;免疫组化显示,CsAP荧光显示于成虫的表皮层和肠支,在囊蚴也有显示,在雷蚴和尾蚴未显示荧光;ELISA分析表明CsAP识别华支睾吸虫病人和日本血吸虫病人存在吸虫间的交叉免疫反应,CsAP及粗抗原识别轻、中、重度感染程度华支睾吸虫病人的差别不明显。重组蛋白免疫大鼠后,总IgG抗体滴度于3周达较高峰,抗体效价大于1∶25 600。明胶降解实验表明:CsAP具降解胶原能力。结论: 上述结果表明,CsAP在大肠杆菌中高效表达,具有较好的免疫原性,但血清诊断价值不理想;CsAP可能既是膜抗原,又是排泄分泌抗原。 相似文献
976.
目的:探讨韧带样型纤维瘤病(desmoid-type fibromatosis,DTF)的临床病理特征,提高对DTF的认识和诊断水平。方法:分析14例DTF的临床特征,HE及免疫组化观察其病理学特征。结果:14例DTF均为女性,年龄22~81岁,中位数31.5岁,12例发生于腹部,右侧胸壁2例。光镜下以纤细的梭形细胞与胶原纤维交错排列为特征,细胞无异型性,核分裂像罕见;免疫组化Vimentin和β-catenin阳性,部分表达SMA,不表达S-100、CD34、CD117、Dog-1。手术切除随访4~113个月,1例复发。结论:DTF好发于年轻女性,需要与多种良、恶性梭形细胞肿瘤鉴别,细胞核表达β-catenin对DTF诊断和鉴别诊断有重要价值,手术切除是主要治疗手段,切缘残瘤有较高的复发风险。 相似文献
977.
目的总结危重心肺疾病患者实施体外膜肺氧合支持方法和效果。方法对5例患者实施体外膜肺氧合支持,年龄27-82岁(平均年龄47岁),体质量53~87kg(平均体质量69.6kg)。5例患者病因不同,分别为:例1,男性,29岁,爆炸伤,心肺功能衰竭:例2,男性,82岁,急性心肺功能衰竭;例3,女性,34岁,急性心源性休克复苏后支持;例4,男性,27岁,心脏外伤,心脏手术后低心排血量;例5,女性,63岁,联合瓣膜置换术后低心排血量。采用静脉-动脉转流,辅助流量40~70ml/(kg·min);间断检测激活凝血时间(ACT)160~200s。结果体外膜肺氧合支持时间22~61h(平均39.4h)。1例未能脱机而死亡,4例成功脱机,3例康复出院。结论体外膜肺氧合支持是抢救危重心肺功能衰竭及心脏手术心功能支持有效方法。 相似文献
978.
Bin Wu Xiaoyin Fu Bo Huang Xinxin Tong Huanqin Zheng Shiguang Huang Fangli Lu 《Parasitology research》2014,113(4):1261-1267
T cells and IFN-γ are essential for controlling the reactivation of toxoplasmic encephalitis (TE), regardless of whether mice are susceptible or resistant to TE. It has been demonstrated that CD8+ T cells exhausted in chronic Toxoplasma gondii infection result in TE reactivation in C57BL/6 mice. However, this phenomenon had not been reported in genetically TE-resistant BALB/c mice. To explore the immune mechanism of TE in different backgrounds of mice, the dynamic expressions of Tim-3, programmed cell death 1 (PD-1), and their ligands (galectin-9, PD-L1, PD-L2) in brain tissues were compared between TE-resistant BALB/c and -susceptible C57BL/6 mice infected with Prugniaud (Pru, a type II strain) of T. gondii in this study. Compared with infected BALB/c mice, there were remarkable pathological changes with significantly higher histological scores in the brains of C57BL/6 mice at 14, 35, 50, and 70 days postinfection (p.i., P?<?0.01); significantly increased mRNA expressions of Tim-3 at 35 (P?<?0.05) and 70 (P?<?0.01)?days p.i.; and significantly increased PD-1 at all the times p.i. (P?<?0.01) in the brains of infected C57BL/6 mice. Furthermore, there were significantly increased mRNA expressions of PD-L1 in the brain of C57BL/6 mice than that in BALB/c mice at all the times p.i. (P?<?0.01). Although the mRNA expressions of galectin-9 (ligand of Tim-3) were increased in the brains of both lineages of mice at all the times p.i., it showed no differences between the two lineages of mice. Our data suggest that the differences of Tim-3 and PD-1/PD-L1 expressions may contribute to the different immune responses between TE-resistant BALB/c and -susceptible C57BL/6 mice infected with Pru strain of T. gondii. 相似文献
979.
980.
目的探讨1例补体因子Ⅰ(complement factorⅠ,CFⅠ)缺乏患儿CFⅠ基因突变、蛋白表达水平、免疫表型及临床特征。方法对1例临床表现为反复头痛伴发热,脑电图及脑脊液检查异常的疑似无菌性脑膜脑炎患儿行免疫学筛查,免疫相关基因新一代测序及ELISA检测CFⅠ蛋白表达。结果该患儿补体C3水平明显降低,抗体水平及外周血精细免疫分型正常,经基因分析发现CFⅠ基因第5号内含子拼接位点发生纯合772+1G>T突变,患儿父母均为该突变的携带者。ELISA检测示患儿CFⅠ蛋白表达量与正常对照相比明显降低。结论通过临床、免疫学筛查、基因分析及蛋白检测,确诊1例发生CFⅠ基因突变的补体缺乏患儿,为此前未见报道的新发突变。对反复发热伴头痛,脑膜脑炎诊断不明确及C3降低的患儿应考虑补体缺乏并进行补体相关基因分析以最终确诊。 相似文献