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AIM:To investigate the effects of FK506 on anti-glomerular basement membrane(GBM) nephritis in rats. METHODS: Anti-GBM nephritis model was elaborated by rabbit anti-rat GBM antibody injection in SD rats in this study. The rats were divided into three groups: FK506 treated group(0.5 mg·kg-1·d-1, sc), untreated nephritis control group and normal control group. FK506 was administered daily six hours after injection of anti-GBM IgG. All the rats were observed urinary protein at the 4th day, the 14th day and the 21st day. At the same time, the kidney specimens were collected, and T cell transforming function was also monitored.RESULTS:Rats injected with rabbit anti-GBM Ab developed heavy proteinuria by 4 days, and serum creatinine and serum urea appeared which kept on the rising. Glmerular hypercellularity, crescents, and protein casts were observed in nephritic rats. By electron microscopy, the thickening of GBM and loss of foot processes were seen. T cell transforming function was higher than normal. But, all pathological changes obviously turned for the better in FK506 treated group. CONCLUSION:FK506 could inhibit the progression of rat anti-GBM nephritis. 相似文献
94.
AIM:To explore the serum levels of certain adhesion molecules and its significance in acute coronary syndrome(ACS). METHODS:The subjects included 40 patients with acute myocardial infarction(AMI) and 40 patients with unstable angina pectoris (UAP). Among the 80 patients, 60 patients accepted a follow-up 4 months. At the same time we selected 40 controls from people who attended a routine health check in the university. Serum levels of E-selectin, sICAM-1, sVCAM-1 were measured by ELISA.RESULTS:Serum levels of E-selectin, sICAM-1, sVCAM-1 were significantly higher in the ACS group(AMI or UAP) than in the control group. Four months later, the levels of E-selectin, sICAM-1 became significantly lower in the follow-up group than in the ACS group, while sVCAM-1 showed no significant difference. CONCLUSION:Serum levels of E-selectin, sICAM-1 may have certain diagnostic value for ACS, and can be a useful marker reflecting the stability of the disease. 相似文献
95.
番木瓜环斑病毒株系的分子生物学方法鉴定 总被引:6,自引:1,他引:6
以PRSV株系特异性引物对PRSV的PRSV126(PRSV日本分离物)、Ys、Vb和Sm等株系进行RT-PCR方法鉴定,引物PR21/PR22能把Ys从Vb和Sm中鉴定出来,PR300/PR301则能把Vb从Ys、Sm和PRSV126中鉴定出来;用限制性内切酶Hae Ⅱ、Sau3A I和Hinf I对PRSV的PRSV126、Ys、Vb和Sm等株系进行单酶切RT-PCR-RFLP分析,Hinf I能把PRSV126与Ys、Vb和Sm鉴别开来,Sau3A I能把Ys与Vb和Sm鉴别开来,Hae Ⅱ则能把Ys与PRSV126、Vb和Sm鉴别开来;以P1/P2为引物,对Vb、Ys和Sm株系进行RT-PCR-RFLP-SSCP分析,结果能一次把三者较好地区别开来。 相似文献
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AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [3-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10-6-10-4 mmol/L) stimulated [3-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [3-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P<0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P<0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10-6-10-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P<0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl2 for 6 h induced an increase cellular MT content by 5.7-fold (P<0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P<0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation. 相似文献
98.
AIM:To examine the effects of recombinant human hepatocyte growth factor(rhHGF) and native calf HGF(cHGF) on SMMC-7721 human hepatocellular carcinoma(HCC) cell line. METHODS:Human HCC cell line culture, photometric assay, and flow cytometric assay were used in this study .RESULTS:A similar type of dose-dependent cell growth inhibition effect on SMMC-7721 human HCC cells by rhHGF(5-20 μg/L) as well as by cHGF(25-100 mg/L) had been found, with the maximal effect at the highest concentration used. Approximately over 50% of the cells treated with rhHGF(5 μg/L, 10 μg/L, 20 μg/L) accumulated in the quiescent G0/G1 phase of the cell cycle over incubation periods for 3 d. CONCLUSION:The growth of SMMC-7721 human HCC cells was strongly inhibited by both rhHGF and cHGF. This might be because the cells exposed to HGF became arrested in the G0/G1 phase. 相似文献
99.
AIM:To establish rat chronic obstructive pulmonary disease(COPD) models by passive cigarette smoking plus intratracheal instillation of lipopolysacchride(LPS) or passive cigarette smoking only, which would be similar to the pathogenesis of human COPD. METHODS:48 Wistar rats were randomly divided into 4 groups.(1) Healthy control I group(n=12), rats were bred 4 weeks;healthy control II group(n=12), rats were bred for 3months. (2) Model group I (n=12), 200μg lipopolysaccharide(LPS) was instilled intratracheally once for every two weeks and the rats were exposured to 5% of cigarette smoke, 0.5 h/d for 4 weeks.(3) Model group II(n=12),rats were exposed to 5% of cigarette smoke, 0.5 h/d for 3 months. The pathologic changes of airways and lung tissues, pulmonary function and blood gas analysis were determined. The airway wall lymphocytes and alveolar macrophages were counted. The cross areas of epithelial layer, smooth muscle layer and lamina propria of bronchi were measured. The hydroxyproline of lung tissue homogenates was determined by biochemistry method.RESULTS:The pathologic changes of airways and lung tissue of two models were similar to but milder than those of COPD patients(biopsy data). The collagen deposition and the cross areas of epithelial layer and smooth muscle layer in airway walls of two model groups were significantly increased than those of control groups(P<0.01,P<0.05).FEV0.3/FVC% of two model groups, PaO2 and SaO2 of model I group were significantly decreased, while Ri and Re in model I group were significantly increased than that of control I group(P<0.05). The PaCO2 and the counts of lymphocytes and alveolar macrophages of both model groups were significantly increased than those of the control groups (P<0.01). Lots of alveolar macrophages had phagocyted smoke granules. The amounts of hydroxyproline of two model groups were significantly increased than those of control group((P<0.05) and were negatively related to the FEV0.3/FVC%, respectively (P<0.01,P<0.01) and positively related to airway resistance of model I group(P<0.01). CONCLUSIONS:COPD rat models were successfully established by passive cigarette smoking plus intratracheal instillation of LPS and cigarette smoking only. The pathologic changes were similar but milder than those of COPD patients. The airway obstruction of model I group was more severe than that of model II group, but they have no significant difference. 相似文献
100.
AIM:To investigate the effect of lansoprazole on gastric ulceration in rats. METHODS:Using the gastric ulcer model induced by hemorrhagic shock, restraint water-immersion stress and pylorus-ligature, the protective effect of lansoprazole (iv) on gastric ulceration was observed. RESULTS:Pretreatment with lansoprazole (7.5-60 mg/kg) significantly inhibited the formation of gastric ulcer in the three models in a dose-dependent manner. The autiulcer efficacy of lansoprazole was similar to that of omeprazole in the equal dose, but stronger than that of omeprazole for ulcer induced by water-immersion stress.CONCLUSION:The intravenously administered lansoprazole inhibited formation of experimental gastric ulcer in rats. 相似文献