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971.
Renoprotective effects of combination of angiotensin converting enzyme inhibitor with mycophenolate mofetil in diabetic rats 总被引:2,自引:0,他引:2
Y. -G. Wu H. Lin H Qian M. Zhao X. -M. Qi G. -Z. Wu S. -T. Lin 《Inflammation research》2006,55(5):192-199
Objective and design Previously it was shown that blocking of the renin-angiotensin system (RAS) by angiotensin converting enzyme (ACE) inhibitors,
or suppression of inflammatory responses by immunosuppressive drugs such as mycophenolate mofetil (MMF) could attenuate renal
injury in diabetic rats. Whether RAS blockade combined with an immunosuppressive drug provides superior renoprotection against
diabetic nephropathy has not been clearly delineated.
Materials Diabetes was induced by injection of streptozotocin after uninephrectomy.
Treatment Rats were randomly separated into five groups: control, diabetes, diabetes treated with enalapril (an ACE inhibitor, 10 mg/kg/d
by gastric gavage), diabetes treated with MMF (10 mg/kg/d by gastric gavage), or diabetes treated with a combination of both
agents and were followed for 8 weeks.
Methods 24 h urinary albumin excretion rate (AER) was determined, renal injury was evaluated, immunohistochemistry for ED-1 macrophage
marker, intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1) were performed, and expression
of transforming growth factor (TGF)-β1 protein was determined by Western blotting analysis.
Results Diabetes was associated with a considerable increase in AER. Both enalapril and MMF retarded the increase in albuminuria,
which was nearly completely abrogated by combination therapy. Increased glomerular volume and tubulointerstitial injury index
in diabetic rats was attenuated by treatment with either enalapril or MMF and further reduced by the combination of the two.
Elevated malondialdehyde levels in renal tissue were reduced by enalapril or MMF and, more effectively, by combined enalapril
with MMF. Renal overexpression of ICAM-1 was not retarded by enalapril and attenuated by MMF or combined enalapril with MMF.
Combination therapy was associated with a superior suppression of diabetes-induced macrophage recruitment and overexpression
of MCP-1 and TGFβ1 compared to either monotherapy in renal tissue.
Conclusion The combination of enalapril and MMF confers superiority over monotherapy in renoprotection, a mechanism which may be at least
partly correlated with synergistic suppression of increased macrophage recruitment and overexpression of MCP-1 and TGF-β1
in renal tissue in diabetic rats.
Received 26 July 2005; returned for revision 5 October 2005; returned for final revision 9 January 2006; accepted by M. Katori
23 January 2006 相似文献
972.
组织型纤溶酶原激活剂及其抑制物的变化与冠心病的关系 总被引:3,自引:0,他引:3
目的:观察冠心病患者纤溶活性的变化及其在冠心病发病中的作用,探讨其临床意义。方法:用酶联免疫双抗夹心(ELISA)法测定58例冠心病患者血浆中组织型纤溶酶原激活剂(t—PA)及纤溶酶原激活抑制物-1(PAI-1)抗原含量,反映纤溶-抗纤溶活性的变化,并对冠心病患者组与对照组纤溶指标进行不同性别间的比较。结果:急性心肌梗死、不稳定心绞痛患者PM-1的含量、PAI-1/t—PA比值明显高于对照组,且急性心肌梗死患者PM-1的含量较不稳定心绞痛患者显著为高。但t—PA在急性心肌梗死、不稳定心绞痛患者均无显著降低。患者组及对照组不同性别间纤溶及抗纤溶水平均未见有显著差异。结论:血栓性疾病与纤溶系统的异常有密切关系。纤溶系统活性的变化及纤溶-抗纤溶的平衡失调在缺血性心脏病的发生、发展中起着重要作用。 相似文献
973.
目的 根据小鼠神经元与T淋巴细胞具有共同抗原Thy-1的特点,利用鼠脑组织制备兔抗鼠T淋巴细胞血清。方法 提取鼠脑组织与弗氏完全佐剂混合,制成油包水乳剂, 免疫2只家兔后,采血,分离血清,用鼠脾淋巴细胞做凝集试验及补体依赖的细胞毒试验确定其活性。结果 制备的抗血清可与鼠脾淋巴细胞发生反应,2只兔抗血清凝集试验的效价分别为1:640及1:1280。抗血清1:320倍稀释后与鼠脾淋巴细胞做补体依赖的细胞毒试验,特异性细胞毒性均为32%。结论 用鼠脑组织制备抗鼠T淋巴细胞血清是一种可行的方法。 相似文献
974.
卵巢癌细胞多种细胞因子基因表达的研究 总被引:1,自引:0,他引:1
本文应用RT-PCR方法,检测5例刚分离的晚期上皮性卵巢癌患者肿瘤细胞和3例卵巢痛患者腹水中肿瘤细胞IL-2、IL-2R、TNF-a,IL-6、TGF-p、IL-10等细胞因子基因的表达,用免疫学方法检测卵巢癌细胞上清液中IL-6活性。结果发现:卵巢癌肿瘤细胞表达IL-6mRNA和抑制性细胞因子TGF-p、IL-10。腹水中存在较多量lL-6可能来自肿瘤细胞。 相似文献
975.
Antoinette MaassenVanDenBrink MSc ; Monique N. Vergouwe MSc ; Roel A. Ophoff PhD ; Pramod R. Saxena MD PhD ; Michel D. Ferrari MD PhD ; Rune R. Frants PhD 《Headache》1998,38(4):288-291
The 5-HT1 receptor agonist, sumatriptan, is highly effective in the treatment of migraine. Some patients, however, do not respond or experience recurrence of the headache. In addition, some patients report chest symptoms after sumatriptan. We investigated whether these different responses could be attributed to genetic diversity of the 5-HT1B receptor, which most likely mediates the therapeutic action and the coronary side effects of sumatriptan. Allele frequencies of two polymorphisms in the 5-HT1B receptor gene ( G861C and T-261G ) were investigated in migraine patients with consistently good response to sumatriptan (n=14), with no response (n=12), with recurrence of the headache (n=12), with chest symptoms (n=13), and in patients without chest symptoms (n=27). Allele frequencies (G:0.74; C:0.26 at nt 861 and T:0.39; G:0.61 at nt -261) did not differ between patient groups, indicating that genetic diversity of the 5-HT1B receptor does not seem to be involved in the different clinical responses to sumatriptan. 相似文献
976.
胰岛素抵抗性高血压大鼠α1肾上腺素受体亚型的改变 总被引:2,自引:0,他引:2
目的和方法:用高糖喂养复制胰岛素抵抗性高血压(insulin-resistanthypertension,IRH)大鼠模型,用放射配体结合实验和离体左心房及主动脉收缩功能实验,观察IRH大鼠α1肾上腺素受体(α1-adrenoceptor,α1-AR)及其3种亚型在心脏和主动脉的改变。结果和结论:IRH大鼠与同龄SD大鼠相比:(1)心脏α1-AR密度下降48%(P<005),而介导的正性变力效应不变。(2)心脏α1-AR3种亚型占α1-AR总数的比例和在介导心脏正性变力效应中的作用表现为α1B-AR增加,α1D-AR减少,而α1A-AR不变。(3)介导主动脉收缩的α1-AR及各亚型对激动剂的敏感性及最大收缩效应均无明显改变。 相似文献
977.
978.
979.
Cytotoxic T lymphocytes (CTL) recognize antigens derived from endogenously expressed proteins presented on the cell surface in the context of major histocompatibility complex (MHC) class I molecules. Because CTL are effective in antiviral and antitumor responses, the delivery of antigens to the class I pathway has been the focus of numerous efforts. Generating CTL by immunization with exogenous proteins is often ineffective because these antigens typically enter the MHC class II pathway. This review focuses on the usefulness of bacterial toxins for delivering antigens to the MHC class I pathway. Several toxins naturally translocate into the cytosol, where they mediate their cytopathic effects, and the mechanisms by which this occurs has been elucidated. Molecular characterization of these toxins identified the functional domains and enabled the generation of modified proteins that were no longer toxic but retained the ability to translocate into the cytosol. Thus, these modified toxins could be examined for their ability to carry peptides or whole proteins into the cytosolic processing pathway. Of the toxins studied—diphtheria, pertussis, Pseudomonas, and anthrax—the anthrax toxin appears the most promising in its ability to deliver large protein antigens and its efficiency of translocation. 相似文献
980.
将应用常规RPHA法检查HBsAg阴性的1074份献血员血清再用ELISA和SPRIA法检测。其中又查出HBsAg、HBeAg和抗-HBc-IgM标志,其阳性率分别达5.96%,2.14%和3.35%,HBV携带率竟高达9.68%。说明用常规RPHA法筛选出的HBsAg阴性献血员仍有传播乙型肝炎的危险。用ELISA法并联检测HBsAg和抗-HBc-IgM,在RPHA法检查HBsAg阴性的献血员中、其阳性率为8.29%,敏感度达85.58%,因而这种并联筛检方法可成为一种切实可行的筛检方法。 相似文献