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Noriyo Kimura Satomi Yonemoto Toshihiko Machiguchi Xuan Li Hideki Kimura Haruyoshi Yoshida 《Hypertension research》2006,29(8):573-580
The major glomerular abnormalities in hypertensive nephrosclerosis are described as glomerular obsolescence (GO), glomerulosclerosis (GS), and glomerular collapse (GC). However, glomerular cellular changes caused by hypertensive insults have not been well analyzed. Using an immunoenzyme method, we examined eleven biopsy samples from patients with hypertensive nephrosclerosis for two synthetic and secreting phenotypes, a-smooth muscle actin (alpha-SMA) and collagen type III (Col. III), and two apoptotic phenotypes, pro-apoptotic molecule Bax and anti-apoptotic molecule BcI-2. Together with the glomerular and vascular changes and interstitial fibrosis (IF) area, the results were scored quantitatively and semi-quantitatively and compared to the clinical findings, which included systolic blood pressure (SBP), mean arterial pressure (MAP), serum creatinine levels (sCr) and creatinine clearance (Ccr), using univariate and multivariate analyses. As a result, GS was frequently observed in the mild-to-moderate hypertensive group (140 < or = SBP<180 mmHg), whereas GC was positively correlated with SBP. Furthermore, there was a positive correlation of GS with mesangial alpha-SMA and Col. III, suggesting that GS was the reflection of these synthetic and secreting phenotypic changes in mesangial cells. Endothelial Bax was positively correlated with Ccr (p<0.01); in contrast, podocytic Bax was positively correlated with sCr (p<0.05) and showed a tendency to correlate with MAP (p=0.054). In conclusion, these findings support the view that mesangial synthetic and secreting phenotypic changes may be a reflection of cellular activation caused by mild-to-moderate hypertension and that apoptotic phenotypic expression in podocytes, rather than endothelial cells, may be related to the development of a severe form of hypertensive nephrosclerosis. 相似文献
74.
多发性硬化患者血清尿酸水平变化的研究 总被引:2,自引:0,他引:2
目的 探讨多发性硬化 (MS)患者血清尿酸 (UA)水平的变化及其临床意义。方法 采用酶定量分析法对 4 3例MS患者和 4 5名正常对照者的血清UA水平进行检测。结果 MS组血清UA水平明显低于对照组 (P <0 0 1)。MS组中病程越长 (P <0 0 1)、神经伤残程度越重 (DSS评分越高 ) (P <0 0 5 ) ,血清UA水平越低 ;女性患者UA水平明显低于男性患者 (P <0 0 0 1) ;经过糖皮质激素治疗后血清UA水平明显回升 (P <0 0 0 1) ,但治疗前血清UA水平越低则疗效越差 (P <0 0 1、P <0 0 5 )。结论 MS患者血清UA水平降低 ,且与MS的病程、伤残程度、疗效及性别密切相关。UA水平升高可能为激素治疗MS的一个作用机制 相似文献
75.
Alex Zacharek Jieli Chen Xu Cui Ang Li Yi Li Cynthia Roberts Yifan Feng Qi Gao Michael Chopp 《Journal of cerebral blood flow and metabolism》2007,27(10):1684-1691
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2. 相似文献
76.
Min Zhang Wen-Bin Li Jin-Xia Geng Qing-Jun Li Xiao-Cai Sun Xiao-Hui Xian Jie Qi Shu-Qin Li 《Journal of cerebral blood flow and metabolism》2007,27(7):1352-1368
Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP. 相似文献
77.
Foley尿管气囊压迫治疗骶前静脉丛大出血的评价(附6例报告) 总被引:5,自引:0,他引:5
目的:评价直肠癌根治术中用Foley尿管气囊压迫治疗骶前静脉丛大出血(MPVP)的临床价值。方法:分析1995~2005年用Foley尿管气囊压迫治疗骶前静脉丛大出血6例的临床资料。结果:6例骶前大出血中全部用Foley尿管气囊压迫控制出血,术中出血量为800~1700mL,Foley尿管于术后4d拔除3例,5d1例,6d2例,均无再出血,会阴切口均一期愈合。结论:Foley尿管气囊压迫治疗骶前静脉丛大出血是一种简单安全有效的治疗方法。 相似文献
78.
79.
The impact of obesity on female reproductive function 总被引:1,自引:0,他引:1
Obesity may be described as the new worldwide epidemic, and its serious impact on morbidity and mortality are well known. As more and more women become obese, the reproductive problems associated with obesity present an ever-growing challenge to physicians involved in their fertility care. The spectrum of reproductive problems associated with obesity encompasses a wide range of disorders including infertility problems, miscarriage and pregnancy complications. In this review, we aim to discuss the impact of obesity on the various aspects of female reproductive function with focus on the clinical aspects of fertility problems in obese women. We finally comment on the available therapeutic options available to this group of women. 相似文献
80.