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目的研究肾草酸钙结石形成对肾组织bikunin基因和间α胰蛋白酶抑制物(IαI)蛋白表达的影响,探讨bikunin在尿结石形成中的意义。方法诱导实验性大鼠肾草酸钙结石模型,收集结石大鼠、正常大鼠、临床肾结石和非结石患者每组各8例的肾组织标本。采用免疫组化、逆转录聚合酶链反应(RT-PCR)和计算机图像分析技术分别检测所有大鼠和人肾组织中bikuninmRNA和IαI蛋白的表达水平。结果正常大鼠和非结石患者肾组织均存在bikuninmRNA和IαI蛋白的表达。肾草酸钙结石形成后,结石大鼠肾组织IαI蛋白的灰度值和bikuninmRNA的相对表达水平分别为198.43±15.17、0.70±0.14;肾结石患者肾组织IαI蛋白的灰度值和bikuninmRNA的相对表达水平分别为263.25±17.41、1.27±0.13,分别和对照组相比,均显著增加(P<0.05)。结论Bikunin作为构成IαI的轻链结构,在肾草酸钙结石形成后,bikuninmRNA的表达迅速增强,提示机体通过肾脏合成更多的bikunin来抑制肾草酸钙结石的形成。 相似文献
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LINDA C PADGETT GE-MING LUI ZENA WERB MATTHEW M LAVAIL 《Experimental eye research》1997,64(6):927-938
Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) play an essential role in both normal and pathological extracellular matrix degradation, and a TIMP has been associated with at least one type of retinal degeneration. We have studied expression of MMP-2 and TIMP-1 by zymography, immunocytochemistry, and immunoblotting in the retinal pigment epithelium (RPE) from normal, aged and diseased retinas. MMPs and TIMPs were found in the rat RPE, interphotoreceptor matrix (IPM), and in media conditioned by human and rat RPE in culture. In other polarized cells, MMPs and TIMP-2 are secreted vectorially towards the basal lamina. In the RPE, however, MMP-2 and TIMP-1 were secreted preferentially from the apical surface, the surface bordering the IPM. These findings provide new evidence that MMPs and TIMPs could play a role in the turnover of IPM components.Cell homogenates and conditioned media from RPE isolated from mutant Royal College of Surgeons (RCS) rats with inherited retinal dystrophy had similar amounts of MMP-2 and TIMP-1 as those from congenic control rats. The secretion of MMP-2 and TIMP-1 from RPE cell cultures isolated from young and aged human donors varied widely. However, with increasing cell passage number, secretion of MMPs and TIMPs from human RPE increased dramatically. Also, growing human RPE on bovine corneal endothelial cell-generated extracellular matrix instead of plastic reduced the secretion of both MMPs and TIMPs. These data suggest that the integrity of Bruch's membrane may serve to regulate RPE functions in MMP and TIMP secretion and that extracellular matrices contain signals that regulate MMP and TIMP synthesis and/or secretion by the RPE. 相似文献
15.
The purpose of the present review was to determine objectively the optimal treatment for the eradication of H. pylori amongst the currently used regimens. A comprehensive literature search provided a data-base relating to the following treatments: dual therapy with an anti-secretory drug plus either amoxycillin or clarithromycin; standard triple therapy, with or without additional anti-secretory drugs; proton pump inhibitor triple therapy; and H2 -receptor antagonist triple therapy. Emphasis was placed on intention-to-treat analyses of eradication rates using all of the available evidence. The criteria used to select the optimal treatment were efficacy (eradication rates), frequency of side-effects, simplicity of the regimen (number of tablets per day and duration of treatment) and cost. The analysis showed that proton pump inhibitor triple therapy (that is, a proton pump inhibitor plus any two of amoxycillin, clarithromycin or a nitroimidazole) was the preferred treatment for the eradication of H. pylori . In particular, the 1-week, low-dose regimen with omeprazole plus clarithromycin plus tinidazole produced the highest eradication rates (>90%) with the lowest frequency of side-effects and at only modest cost. 相似文献
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I. Hilakivi L. Ahtee J. O. Rinne T. Taira L. M. J. Attila P. Marjamäki 《Journal of neural transmission (Vienna, Austria : 1996)》1995,102(2):139-148
Summary Rats were treated with desipramine 5mg/kg, nomifensine 10mg/kg, zimelidine 25 mg/kg or with 0.9% sodium chloride once a day during the second and third weeks after birth, and brain stem, caudate/putamen and cortical monoamines, and caudate/putamen dopamine D1 (3[H]SCH 23390) and D2 (3[H]spiroperidol) receptor binding were measured when rats were at two months of age. In the brain stem, the concentration of 3-methoxy-4-hydroxy-phenyl glycol was increased in nomifensine rats and the ratio of 5-hydroxyindoleacetic acid to 5-hydroxytryptamine was increased in zimelidine rats. In the caudate/putamen, the concentrations of 3,4-dihydroxyphenylacetic acid and homovanillic acid and the ratio of homovanillic acid to dopamine were increased in desipramine rats; neither3[H]SCH 23390 nor3[H]spiroperidol binding were affected by any of the three monoamine uptake inhibiting antidepressants studied. In the cortex, the ratio of 5-hydroxyindoleacetic acid to 5-hydroxytryptamine was increased in desipramine and zimelidine rats. The findings suggest that desipramine but not nomifensine increases the metabolism of dopamine in the caudate/ putamen and nomifensine but not desipramine increases the metabolism of norepinephrine in the brain stem, and furthermore that the metabolism of serotonin is affected by desipramine as well as by zimelidine. It is possible that also treatment of women with these drugs during late pregnancy causes long-lasting changes in the brain of human fetus. 相似文献
18.
T. J. C. Faes G. A. Yff O. De Weerdt P. Lanting J. J. Heimans F. W. Bertelsmann 《Journal of neurology》1993,240(3):156-160
To evaluate the effects of the aldose reductase inhibitor Ponalrestat (Statil) on diabetic autonomic neuropathy, a double-blind placebo controlled trial was carried out on a group of 34 diabetic patients with documented cardiac autonomic neuropathy. After a 4-week, placebo run-in period, patients were randomised for treatment with 600 mg Statil or placebo for another 24 weeks. Moreover, the reliability of the autonomic nerve function tests was investigated by comparing the results at onset and at week 4. Fifteen patients treated with Statil and 12 with placebo completed the study. Neither symptom scores nor cardiovascular reflexes, pupil reflexes and skin vasomotor reflexes improved after Statil therapy, which led us to conclude that Statil is not effective in the treatment of diabetic autonomic neuropathy. Reliability coefficients for cardiovascular reflexes and pupil reflex showed high values, ranging from 60% to 80%. Therefore these methods are recommended in future therapy trials. 相似文献
19.
Juraj Sprung MD PhD David Distel CRNA Jeffrey Grass MD Eric L. Bloomfield MD Ian C. Lavery MD 《Journal of clinical anesthesia》1996,8(8):662-665
We describe a patient in whom long-term monoamine oxidase (MAO) inhibitor therapy was discontinued 20 days before surgery with general anesthesia. This patient developed severe perioperative hypotension after administration of 10 mg of bupivacaine through an epidural catheter, which was corrected only after potent vasopressor therapy. We attribute this hemodynamic instability to attenuation of this patient's sympathetic tone based on several mechanisms: (1) residual effect of long-term administration of MAO inhibitor that caused a decrease in the number of β-adrenergic receptors (adrenergic subsensitivity due to receptor down-regulation), (2) recovered MAO activity causing effective degradation of sympathetic amines, and (3) combined attenuating effects of general and epidural anesthesia on sympathetic tone. 相似文献
20.
Y Namba T Moriyama M Kyo K Oka Y Kokado Y Shi R Imamura N Ichimaru A Okuyama S Takahara 《Clinical transplantation》2004,18(S11):29-33
Abstract: Angiotensin-converting enzyme inhibitor (ACEI) has become recognized as agents that have renoprotective effects in the treatment of progressive renal diseases including post-transplant kidneys. Previously we demonstrated the safety and effectiveness of ACEI treatment on the hypertensive proteinuric post-transplant patients ( N = 10) who had been followed up for 12 months. However, not all patients show good response in urinary protein reduction. We aimed to analyse the histopathological factor(s) affecting the responsiveness of proteinuria to ACEI treatment. Fourteen post-transplant patients with proteinuria who were treated with ACEI and underwent allograft biopsy were analysed. Eight patients showed 50% or more reduction in proteinuria (responder). The other 6 patients showed less (< 50%) reduction in proteinuria (non-responder). There was no difference in clinical characteristics (BP, renal function, donor age, recipient body mass index), dietary sodium or protein intake, and diuretic use between the two groups. As a histopathological characteristic, glomerular size in responder group was significantly larger than that in non-responder group. This suggests that the large glomerular size at least partly contributes to the responsiveness in urinary protein reduction to ACEI treatment in kidney allograft recipients with proteinuria. 相似文献