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21.
The renal insulin-like growth factor-I (IGF-I) system has been implicated in the pathogenesis of renal hypertrophy, altered hemodynamics, and extracellular matrix expansion associated with early diabetes. The relative abundance of IGF binding proteins (IGFBPs) in the renal microenvironment may modulate IGF-I actions. However, the precise IGFBPs expressed in the glomerular and tubulointerstitial compartments during diabetic renal growth have not been characterized. In the present study, in situ hybridization studies were performed to examine the expression of IGFBP-1 to -6 messenger RNAs (mRNAs) 3, 7, and 14 days after streptozotocin (STZ) injection in rats. In control, nondiabetic kidneys, all six IGFBP mRNAs were differentially expressed with a predominance of IGFBP-5. The onset of renal hypertrophy in STZ-induced diabetes was associated with a rapid and site-specific induction of IGFBP-1, -3, and -5 mRNAs. In contrast, basal expression of IGFBP-2, -4, and -6 mRNAs was not altered in diabetic rats. IGFBP-5 mRNA expression increased in diabetic glomeruli, cortical, and inner medullary peritubular interstitial cells at days 3, 7, and 14. Although normal glomeruli failed to express IGFBP-3, it was induced concomitantly with IGFBP-5 in diabetic glomeruli and cortical peritubular interstitial cells. IGFBP-1 mRNA levels also increased in cortical tubular cells at each time point tested. Peak induction of IGFBP-3 and -5 was observed at day 3, whereas IGFBP-1 was delayed until day 7. IGFBP-1, -3, and -5 mRNA levels declined by day 14, but remained persistently elevated above control. By immunoperoxidase staining, similar alterations in the pattern of IGFBP-3 and -5 protein expression were observed at each time point. The preferential and site-specific increase in IGFBP-1, -3, and -5 suggest that these IGFBPs may regulate the local autocrine and/or paracrine actions of IGF-I and contribute to the pathogenesis of the early manifestations of diabetic nephropathy.  相似文献   
22.
The risk of late-onset cytomegalovirus (CMV) infection remains a concern in seronegative kidney and/or pancreas transplant recipients of seropositive organs despite the use of antiviral prophylaxis. The optimal duration of prophylaxis is unknown. We studied the cost effectiveness of 6- versus 3-mo prophylaxis with valganciclovir. A total of 222 seronegative recipients of seropositive kidney and/or pancreas transplants received valganciclovir prophylaxis for either 3 or 6 mo during two consecutive time periods. We assessed the incidence of CMV infection and disease 12 mo after completion of prophylaxis and performed cost-effectiveness analyses. The overall incidence of CMV infection and disease was 26.7% and 24.4% in the 3-mo group and 20.9% and 12.1% in the 6-mo group, respectively. Six-month prophylaxis was associated with a statistically significant reduction in risk for CMV disease (HR, 0.35; 95% CI, 0.17 to 0.72), but not infection (HR, 0.65; 95% CI, 0.37 to 1.14). Cost-effectiveness analyses showed that 6-mo prophylaxis combined with a one-time viremia determination at the end of the prophylaxis period incurred an incremental cost of $34,362 and $16,215 per case of infection and disease avoided, respectively, and $8,304 per one quality adjusted life-year gained. Sensitivity analyses supported the cost effectiveness of 6-mo prophylaxis over a wide range of valganciclovir and hospital costs, as well as variation in the incidence of CMV disease. In summary, 6-mo prophylaxis with valganciclovir combined with a one-time determination of viremia is cost effective in reducing CMV infection and disease in seronegative recipients of seropositive kidney and/or pancreas transplants.Cytomegalovirus (CMV) infection remains one of most common opportunistic infections in solid organ transplant patients despite availability of specific and efficacious anti-viral drugs.1,2 Solid organ transplant patients who have a negative CMV serology and receive an organ from a positive CMV serologic donor (D+/R−) have the highest incidence of CMV disease with and without prophylaxis.25 Although the risk for CMV disease persists for life, the majority of cases occur shortly after completion of prophylaxis, often within the first year after transplant.6 CMV disease causes significant morbidity, increases mortality, and is associated with inferior transplant outcomes, particularly in the case of kidney transplantation.710 Furthermore, the presence of CMV disease is one of the most frequent infectious causes of hospitalization early after transplantation, increasing the total cost of kidney transplantation and reducing its overall effectiveness.7,1113Valganciclovir (VGCV) is an effective anti-CMV agent for prophylaxis and treatment of CMV disease that is widely used in transplantation.2,1416 Although the recommended dose for CMV prophylaxis is 900 mg daily adjusted for renal function, a recent study showed that VGCV at 450 mg daily provides similar drug exposure compared with oral ganciclovir (GCV) at 1000 mg three times daily in kidney transplant patients, a dose similarly effective for CMV prophylaxis.2,17 In most studies, VGCV prophylaxis consisted of 100 d after transplant, after which time the risk of CMV infection and disease increased.2,18,19 Extending the duration of VGCV prophylaxis beyond the early post-transplant period may abrogate this transient increase in the risk of infection and disease.20,21 In this regard, the optimal duration of prophylaxis for CMV D+/R− patients has not been determined and is the subject of ongoing study.22 Cost, efficacy, and safety are important factors in determining the optimal duration of VGCV prophylaxis. Over the past two decades, various strategies have been used including pre-emptive versus universal prophylaxis and shorter versus longer period of prophylaxis.20,21,23,24 Although several clinical studies comparing universal prophylaxis versus pre-emptive anti-viral therapy have found similar efficacy and cost in managing CMV infection across various combinations of donor and recipient CMV serologic status, two meta-analyses did find that the use of universal prophylaxis was associated with reduced risk for CMV disease and death.2326This study is based on a single center experience comparing two CMV prophylaxis strategies. We report here the clinical outcome and cost-effectiveness analyses of 6- versus 3-mo VGCV prophylaxis in CMV D+/R− de novo kidney and/or pancreas transplant patients.  相似文献   
23.
目的:探讨肝细胞生长因子(hepatocyte growth factor,HGF)/c-Met轴介导内皮祖细胞(endothelial progenitor cells,EPCs)移植入低氧性肺动脉高压(hypoxic pulmonary artery hypertension,HPAH)大鼠对大鼠的肺动脉压力和肺血管重构的影响。方法:构建HPAH模型大鼠;大鼠骨髓原代EPCs提取、培养和鉴定;构建c-Met腺病毒并转染EPCs;将大鼠分为c-Met-EPCs细胞组、EPCs细胞组、肺动脉高压组和正常组,每组10只。前2组大鼠通过尾静脉分别输注c-Met-EPCs细胞和EPCs细胞,后2组大鼠输注生理盐水;饲养一周后检测平均肺动脉压力(mean pulmonary arterial pressure,mPAP)和右心室肥大指数(right ventricle hypertrophy index,RVHI);透射电镜检测肺动脉超微结构改变,肺组织病理切片观察肺小动脉改变;ELISA法测定血清内皮素-1(endothelin-1,ET-1)含量,Griess法测定血清一氧化氮(nitric oxide,NO)含量。结果:c-Met-EPCs细胞组、EPCs细胞组、肺动脉高压组和正常组4组大鼠的mPAP值分别为(23.17±3.07)、(30.85±3.15)、(33.55±5.47)、(20.30±1.99) mmHg;RVHI值分别为(32.48±2.38)%、(37.54±4.42)%、(38.53±2.81)%、(26.05±3.05)%;血清ET-1值分别为(69.45±6.32)、(95.76±7.31)、(99.14±8.39)、(62.35±6.06) ng/L;血清NO值分别为(99.63±11.40)、(56.07±3.32)、(48.83±6.56)、(125.50±12.26) μmol/L。EPCs细胞组、肺动脉高压组大鼠的mPAP、RVHI和血清ET-1含量明显高于正常组(P<0.05);c-Met-EPCs细胞组较EPCs细胞组、肺动脉高压组明显降低(P<0.05)。EPCs细胞组、肺动脉高压组大鼠的血清NO含量明显低于正常组(P<0.05);c-Met-EPCs细胞组较EPCs细胞组、肺动脉高压组明显升高(P<0.05)。透射电镜显示EPCs细胞组、肺动脉高压组肺动脉中膜平滑肌细胞线粒体和内质网肿胀、内皮细胞中断不连续,而c-Met-EPCs细胞肺动脉中膜平滑肌细胞线粒体和内质网肿胀不显著。肺组织病理切片显示EPCs细胞组、肺动脉高压组肺血管重构明显,而c-Met-EPCs细胞组肺血管重构减轻。结论:HGF/c-Met轴介导内皮祖细胞移植入低氧性肺动脉高压大鼠后可明显降低肺动脉压力和和改善肺血管重构,其机制可能与抑制ET-1释放和促进NO产生有关。  相似文献   
24.
Racial differences on the outcome of simultaneous pancreas and kidney (SPK) transplantation have not been well studied. We compared mortality and graft survival of African Americans (AA) recipients to other racial/ethnic groups (non‐AA) using the national data. We studied a total of 6585 adult SPK transplants performed in the United States between January 1, 2000 and December 31, 2007. We performed multivariate logistic regression analyses to determine risk factors associated with early graft failure and immune‐mediated late graft loss. We used conditional Kaplan–Meier survival and multivariate Cox regression analyses to estimate late death‐censored kidney and pancreas graft failure and death between the groups. Although there was no racial disparity in the first 90 days, AA patients had 38% and 47% higher risk for late death‐censored kidney and pancreas graft failure, respectively (p = 0.006 and 0.001). AA patients were twice more likely to lose the kidney and pancreas graft due to rejection (OR 2.31 and 1.86, p = 0.002 and 0.008, respectively). Bladder pancreas drainage was associated with inferior patient survival (HR 1.42, 95% CI 1.15, 1.75, p = 0.001). In the era of modern immunosuppresion, AA SPK transplant patients continue to have inferior graft outcome. Additional studies to explore the mechanisms of such racial disparity are warranted.  相似文献   
25.
BackgroundTo introduce and determine the value of optimized strategies for the management of urological tube-related emergencies with increased incidence, complexity and operational risk during the global spread of coronavirus disease 2019 (COVID-19).MethodsAll emergent urological patients at Tongji Hospital, Wuhan, during the period of January 23 (the beginning of lockdown in Wuhan) to March 23, 2020, and the corresponding period in 2019 were recruited to form this study’s COVID-19 group and control group, respectively. Tongji Hospital has the most concentrated and strongest Chinese medical teams to treat the largest number of severe COVID-19 patients. Patients in the control group were routinely treated, while patients in the COVID-19 group were managed following the optimized principles and strategies. The case incidence for each type of tube-related emergency was recorded. Baseline characteristics and management outcomes (surgery time, secondary complex operation rate, readmission rate, COVID-19 infection rate) were analyzed and compared across the control and COVID-19 periods.ResultsThe total emergent urological patients during the COVID-19 period was 42, whereas during the control period, it was 124. The incidence of tube-related emergencies increased from 53% to 88% (P<0.001) during the COVID-19 period. In particular, the incidence of nephrostomy tube-related (31% vs. 15%, P=0.027) and single-J stent-related problems (19% vs. 6%, P=0.009) increased significantly. The mean surgery times across the two periods were comparable. The number of secondary complex operations increased from 12 (18%) to 14 (38%) (P=0.028) during the COVID 19-period. The number of 2-week postoperative readmission decreased from 10 (15%) to 1 (3%) (P=0.049). No participants contracted during the COVID-19 period.ConclusionsUrological tube-related emergencies have been found to have a higher incidence and require more complicated and dangerous operations during the COVID-19 pandemic. However, the optimized management strategies introduced in this study are efficient, and safe for both urologists and patients.  相似文献   
26.
绝经前后诸证是指妇女在绝经前后,围绕月经紊乱或绝经出现的一系列不适证候。韩冰教授善用奇经八脉理论,在补益肾气,滋阴扶阳的基础上重视维脉作用,阳维病者重视调和营卫,燮理阳维,阴维病者重视通养心肾,通维和络。  相似文献   
27.
目的:探讨小儿室间隔缺损(ventricular septal defect,VSD)修补术后残余分流的发生原因、常见部位、预后、影响预后的因素及干预时机。方法:回顾性分析2013年1月至2017年1月重庆医科大学附属儿童医院行VSD修补术后239例残余分流患者的临床资料,包括患者性别、手术年龄、体质量、术前左右心室压差、术前VSD分流方向、补片材料、体外循环时间、残余分流的大小及部位、残余分流的血流速度,运用单因素及多因素Cox回归分析患者预后的影响因素。结果:239例残余分流患者均未再次干预,155例(64.85%)残余分流自行愈合;84例(35.15%)未愈合。小于4 mm残余分流219例,153例(69.86%)自愈;大于4 mm残余分流20例,2例(10%)自愈(P<0.005)。单因素Cox分析结果表明,术前左右心室压差(P=0.028)、体外循环时间(P=0.006)、残余分流大小(P=0.003)、残余分流血流速度(P=0.00)是影响患者预后的因素(P<0.05);而多因素Cox回归分析显示体外循环时间(P=0.017)、残余分流血流速度(P=0.019)...  相似文献   
28.
崩漏是妇科的常见病与疑难重症之一,古代中医文献中有关崩漏病因病机及治则治法的研究记载极为丰富,而从奇经八脉理论辨治崩漏是其中一个重要的组成部分。其发展源流,滥觞于内经时期,历经数千年众多医家的完善发展,流传至今;而究其辨证要点当先审具体经脉,辨明寒热虚实,再结合脏腑辨证。  相似文献   
29.
为研究海马 杏仁核的超微结构改变与颞叶癫痫的关系 ,对 35例颞叶癫痫病人行海马 杏仁核切除术 ,并对海马 杏仁核组织进行超微结构分析。痫灶区海马神经元以神经细胞固缩、变性为著 ,并可见有髓纤维的松解和粘连。轴索萌发出的新突出物、微管及微丝在无髓纤维上不规则排列和缠绕。神经毡内突触前终末兴奋性递质小泡增多 ,嵴消失 ,粗面内质网扩张 ,多聚核糖体解聚 ,并可见大量脂褐素及脂滴 ,星形细胞轻度水肿。提示颞叶癫痫发作不仅仅是单纯的生理生化改变所引起暂时性脑功能失调 ,其病理改变在颞叶癫痫的形成和持续状态具有重要的作用  相似文献   
30.
目的:研究益气活血法对气虚血瘀脑缺血再灌注损伤大鼠血脑屏障(BBB)通透性及细胞间粘附分子(ICAM-1)、基质金属蛋白酶(MMP-2/9)的影响。方法:采用游泳力竭法制作出大鼠气虚血瘀模型,然后用线栓法阻断大鼠大脑中动脉(MCA)2h,再灌注3d、7d后,测定脑组织脑含水量、伊文思蓝(EB)含量,用免疫组化法测定ICAM-1、MMP-2/9蛋白表达的变化。结果:与模型组比较,各治疗组脑含水量、EB含量、ICAM-1、MMP-2/9蛋白表达水平显著降低,益气活血法优于益气法、活血法。结论:益气活血法具有降低BBB通透性的作用,其机制可能是通过减少ICAM-1、MMP-2/9蛋白表达而发挥BBB保护作用。  相似文献   
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