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991.
目的探讨G蛋白偶联受体激酶4(G protein-coupled receptor kinase 4,GRK4)对内皮素B型受体(endothelin receptor B,ETB)的异常调节在原发性高血压中的作用及机制。方法选用12~14周龄,体质量300 g左右的雄性自发性高血压大鼠(spontaneously hypertensive rats,SHRs)及其对照鼠(Wistar-Kyoto,WKY)各10只,通过无创鼠尾测压仪测定血压,采用右肾上腺静脉插管灌注ETB受体特异性激动剂BQ3020后观察尿流速及尿钠排泄率,荧光定量PCR检测大鼠肾脏GRK4 mRNA水平,Western blot测定大鼠肾脏GRK4及ETB受体的蛋白表达差异,免疫共沉淀法检测ETB受体磷酸化情况,在动物水平观察高血压状态下ETB受体的功能情况。结果 ETB受体激动剂BQ3020对WKY大鼠有明显利尿排钠作用,且这种利尿排钠作用可以被ETB受体抑制剂BQ788阻断,但在SHR大鼠BQ3020的利尿排钠作用受损[尿流速:(11.23±2.16)vs(3.49±1.32),P<0.05];尿钠排泄率:[(1 551.43±393.47)vs(601.16±128.15),P<0.05];在SHR大鼠肾皮质GRK4的蛋白水平及mRNA水平均较WKY大鼠高[蛋白:(1.38±0.10)vs(0.85±0.07),P<0.05];mRNA:[(2.23±0.15)vs(0.78±0.16),P<0.05],SHR大鼠ETB受体总蛋白水平与WKY大鼠相比差异无统计学意义(P>0.05),但ETB受体磷酸化水平增高。结论 GRK4可能通过对内皮素B型受体的异常调节,参与了原发性高血压发生与发病。 相似文献
992.
Curtis JP Alexander JH Huang Y Wallentin L Verheugt FW Armstrong PW Krumholz HM Van de Werf F Danays T Cheeks M Granger CB;ASSENT- ASSENT- Investigators 《The American journal of cardiology》2004,94(3):279-283
We investigated the effect of smaller dose, weight-adjusted heparin with earlier monitoring of activated partial thromboplastin time on the incidence of ischemic and hemorrhagic complications in patients with ST-elevation myocardial infarction treated with full-dose tenecteplase. We compared the outcomes of patients enrolled in the Second Assessment of the Safety and Efficacy of a New Thrombolytic Regimen (ASSENT-2; n = 8,461) who received heparin stratified by weight (patients weighing >67 kg received a 5,000-U bolus plus infusion at 1,000 U/hour; those weighing < or =67 kg received a 4,000-U bolus plus infusion at 800 U/hour) with patients in ASSENT-3 who received weight-adjusted heparin (60-U/kg bolus, maximum 4,000 U/hour, followed by a 12-U/kg/hour infusion, maximum 1,000 U/hour). Compared with patients in ASSENT-2, those in ASSENT-3 had similar rates of 30-day mortality, recurrent infarction, and intracranial hemorrhage, less major bleeding (2.2% vs 4.7%, p <0.001), and less refractory ischemia (6.5% vs 8.6%, p <0.001). After adjustment for baseline characteristics, patients in ASSENT-3 had similar rates of 30-day mortality (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.77 to 1.19) and intracranial hemorrhage (OR 1.02, 95% CI 0.61 to 1.69) but less major bleeding (OR 0.49, 95% CI 0.35 to 0.67) than did patients in ASSENT-2. These findings support the use of smaller dose, weight-adjusted heparin in patients with ST-elevation myocardial infarction treated with tenecteplase. 相似文献
993.
Dr. Toshiyuki Matsui M.D. Ph.D. Nobuaki Hayashi M.D. Kenshi Yao M.D. Ph.D. Tsuneyoshi Yao M.D. Ph.D. Kuniaki Takenaka M.D. Ph.D. Toshio Hoashi M.D. Ph.D. Satoshi Takemura M.D. Ph.D. Akinori Iwashita M.D. Ph.D. Akira Tanaka M.D. Ph.D. Mitsuru Koga M.D. Ph.D. 《Diseases of the colon and rectum》1998,41(6):797-801
Typical Turcot's syndrome is characterized by the association of a brain glioma together with multiple colonic polyposis, in which the number of polypoid lesions is small and the association of colonic cancer occurs at a younger age than in familial adenomatous polyposis. We describe a family in which both the father and his son presented with typical Turcot's syndrome without parental consanguinity. This is the first report of a family that is considered to follow an autosomal dominant inheritance. After reviewing 25 documented cases in which the average age of death was 20.3 years old, it was learned that the major cause of death was brain tumor (76 percent) and the minor cause was colon cancer (16 percent). Patients were very young and, therefore, unlikely to have produced a child before their death. These facts seem to support the theory that Turcot's syndrome is an autosomal dominant disorder. 相似文献
994.
995.
目的探索螺内酯对门脉高压实验犬和肝硬变患者门脉血流动力学的作用.方法用直接门脉插管测压和99mTcMIBI心肝放射性摄取比值(H/L)测定慢性胆总管结扎肝硬变犬(n=16)门静脉压力和门体分流,口服螺内酯20mg/(kg·d).肝硬变患者14例测定H/L,门静脉内径和流速后口服螺内酯80mg/d,4wk为1疗程.结果完成试验的犬13只治疗前后门脉压力(kPa)从259±051下降为242±047(P<005),H/L从033±006降至030±008(P<005).14例肝硬变患者治疗前后H/L值从120±026降为102±034(P<005),门脉内径(mm)从139±23缩小为123±20(P<005).门静脉流速明显增加.结论螺内酯口服可降低门脉压力和门体分流. 相似文献
996.
Rui Li Lei Miao Liyan Qin Yang Xiang Xiaojin Zhang Hui Peng Mailamuguli Yuping Sun Hua Yao 《International journal of clinical and experimental pathology》2015,8(9):9812-9823
Background: Gout is an inflammatory disease in which genetic factors play a role. ABCG2 is a urate transporter, and the Q141K and Q126X variants of ABCG2 have been associated with a risk of developing gout, though previous studies of these associations have been inconsistent. Therefore, we conducted a meta-analysis to explore the relationship between these genetic variants and gout. Methods: We examined 8 electronic literature databases. In total, 9 eligible articles on the associations between the Q141K (rs2231142) and Q126X (rs72552713) variants and gout risk, including 11 case-control studies were selected. We used odds ratios (OR) and 95% confidence intervals (CI) to assess the strength of these relationships in dominant, recessive, and co-dominant models. Results: This study included 6652 participants (2499 gout patients and 4153 controls). The Q141K variant was found to significantly increase the risk of gout in Asians (dominant model: OR=2.64, 95% CI=2.04-3.43, P=0.02 for heterogeneity; recessive model: OR=3.19, 95% CI=2.56-3.97, P=0.28 for heterogeneity; co-dominant model: OR=1.37, 95% CI=1.18-1.59, P=0.09 for heterogeneity) and other populations (dominant model: OR=1.85, 95% CI=1.20-2.85, P<0.0001 for heterogeneity; recessive model: OR=3.78, 95% CI=2.28-6.27, P=0.19 for heterogeneity; co-dominant model: OR=1.48, 95% CI=1.26-1.74, P=0.19 for heterogeneity). The Q126X variant also significantly increased the risk of gout in Asians (dominant model: OR=3.87, 95% CI=2.07-7.24, P=0.06 for heterogeneity). Conclusions: These results suggest associations between the rs2231142 and rs72552713 ABCG2 gene polymorphisms and gout risk, which led to unfavorable outcomes. However, studies with larger sample sizes and homogeneous populations should be performed to confirm these results. 相似文献
997.
Xiaomin Zhang Xi Chen Juan Liu Xiushuai Dong Yinglan Jin Yaoyao Tian Yanming Xue Liyan Chen Yuying Chang Yao Liu Jinghua Wang 《International journal of clinical and experimental pathology》2015,8(11):15489-15496
WISP1, a Wnt-induced secreted protein, has been found to have anticancer activity. ALL is a leading cause of death. Here we investigate the WISP1 effects on ALL Jurkat cells. Cell viability was assessed by CCK-8. Cell cycle and apoptosis were detected by flow cytometry. Mitochondrial membrane potential (MMP) was monitored using TMRM. Generation of reactive oxygen species (ROS) was quantified using DCFH-DA. Western blot was used to detect the expression of cell proliferation and apoptosis related genes. The results showed that knockdown of WISP1 significantly inhibited proliferation of Jurkat cells. Parallelly, cell cycle distribution was increased at G1 phase and apoptotic rate was induced after WISP1 knockdown. Furthermore, knockdown of WISP1 induced apoptosis of Jurkat cells was also associated with loss of MMP and generation of ROS. Western blot results showed that the protein expression p-AKT, PCNA, CDK1, P-ERK, CDK2, VEGF, VEGFR2 and Bcl2 were decreased, while the expression of Bax was up-regulated. In conclusion, WISP1 plays an important role in proliferation and apoptosis of Jurkat cells in mitochondria dependent pathway, the specific mechanisms need further study. 相似文献
998.
Kun Yao Xue-Ling Qi Xi Mei Tao Jiang 《International journal of clinical and experimental pathology》2015,8(2):2079-2084
We describe a rare case of gliosarcoma with primitive neuroectodermal, osseous, cartilage and adipocyte differentiation. A 57-year-old man experienced a month history of headache, nausea and vomiting. Worse yet, the headache has become more severe for the past 6 days. Magnetic resonance (MR) images disclosed a lesion with operative indications located in the right frontal lobe. Then the tumor was macroscopically totally removed. Histologically, the tumor showed two kinds of components. One kind of the tumor cells appeared typical astrocytic tumor cells with anaplastic appearance. The other kind of the tumor cells appeared sheets of small round hyperchromatic cells, which presented a kind of pancreatic neuroendocrine tumor (PNET)-like structure. These sheets of small round cells were surrounded by a large number of relative-sparse-spindle cells. Multiple separate distinct areas of adipose tissue, osteoid matrix laid down and cartilage tissue were also identified. Immunohistochemically, a portion of typical astrocytic tumor cells and some small round hyperchromatic cells showed GFAP positivity. Small round hyperchromatic cells were positive for S-100, Fli-1, Nestin, MAP-2 and Syn. A large amount of relative sparse spindle cells (sarcomatous areas) were positive for vimentin. In addition, reticulin staining demonstrated expression of reticular fibers in relative-sparse-spindle cells areas but not in the astrocytic tumor cells and small round hyperchromatic cells areas. Molecular cytogenetic analyses demonstrated PTEN allele loss and no evidence of amplification of EGFR in both the astrocytic tumor cells, PNET-like structure and sparse spindle cells areas. These data suggest that this tumor was a gliosarcoma with primitive neuroectodermal, osseous, cartilage and adipocyte differentiation. To our knowledge, this is a rare gliosarcoma , reporting our additional new case would add to the better understanding of this tumor. 相似文献
999.
Yu Bai Yong-Lian Wang Wen-Jian Yao Ling Guo Hui-Fang Xi Song-Yue Li Bao-Sheng Zhao 《International journal of clinical and experimental pathology》2015,8(1):824-829
Introduction: miR-32 has recently been found to be implicated in many critical processes in various types of human cancer. However, its clinical significance in human non-small cell lung cancer (NSCLC) has not yet been elucidated. In the present study, we investigated the expression of miR-32 in NSCLC and analyzed its association with clinical features and prognosis of NSCLC patients. Methods: Quantitative real-time PCR (qRT-PCR) was used to measure expression level of miR-32 in lung cancer cell lines, normal bronchial epithelial cells, 90 pairs of tumor samples and adjacent non-tumor tissues. To determine its prognostic value, overall survival was evaluated using the Kaplan-Meier method. Univariate and multivariate analysis were performed using the Cox proportional hazard analysis. Results: The expression of miR-32 was significantly decreased in lung cancer cell lines and NSCLC tissues compared with normal bronchial epithelial cells and adjacent non-tumor tissues (P < 0.05). This reduction of miR-32 was associated with tumor stage and lymph node metastasis (P < 0.05). Moreover, Kaplan-Meier analysis demonstrated that patients with low miR-32 expression had shorter overall survival time than those with high miR-32 expression (P < 0.05). Univariate analysis revealed statistically significant correlations between overall survival and miR-32 level, tumor stage and lymph node metastasis (P < 0.05). Furthermore, miR-32 levels, tumor stage and lymph node metastasis were independently associated with overall survival (P < 0.05). Conclusions: Our results provided the first evidence that down-regulation of miR-32 was correlated with NSCLC progression, and miR-32 might be a potential molecular biomarker for predicting the prognosis of patients. 相似文献
1000.
Zhe Fan Jihong Yao Yang Li Xiaowei Hu Huizhu Shao Xiaofeng Tian 《International journal of clinical and experimental pathology》2015,8(4):3451-3459
Objective: To investigate the anti-inflammatory and antioxidant effect of curcumin on lung lesion induced by intestinal ischemia reperfusion injury (IIR). Methods: Rats were divided into four groups: sham, intestinal IIR (IIR), 1 mg/kg of curcumin treatment group (1 mg/kg), and 5 mg/kg of curcumin treatment group (5 mg/kg). Curcumin was given respectively (1 mg/kg and 5 mg/kg) following the above doses. IIR was produced by 1 h of intestinal ischemia followed by 2 h of reperfusion. Rats were sacrificed at the end of reperfusion and lung tissues were collected for biochemical and histopathological examination in 4 groups. Lung tissues histology and bronchoalveolar lavage fluid (BALF) protein were assayed. Serum IL-6, lung superoxide dismutase (SOD) and myeloperoxidase (MPO) were measured. The expression level of NF-κB and ICAM-1 (including immunohistochemical analysis and western blot analysis) were also measured. Results: Lung tissue injury induced by IIR was obviously observed through pathology and BALF protein. MPO activity, IL-6 level and ICAM-1 expression were significantly increased with the elevation of NF-κB, simultaneously, SOD activity was decreased. With Treatment of curcumin, pathology and BALF protein of lung tissue were improved clearly. Inflammatory indexes (MPO activity, IL-6 level and ICAM-1) were improved and antioxidant index (SOD activity) was enhanced paralleled with NF-κB. Conclusion: Using curcumin effectively prevented IIR-induced lung injury. Anti-inflammatory and antioxidant effects of curcumin could be observed by inhibiting the pathway of NF-κB. 相似文献