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31.
The liquid chromatography‐mass spectrometry (LC‐MS) following on from the two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE) technique was applied for the analysis of proteins in a renal stone found in a hyperuricemic patient. This technique was sensitive enough to detect small quantities of proteins even in a renal stone.  相似文献   
32.
The study was carried out in 31 workers co-exposed to cadmium, lead and zinc fumes and dusts in a zinc ore refinery. Urinary cadmium, lead, zinc, β2-M levels and NAG activities were determined to evaluate the possible dose-effect relationship between these parameters. A correlation was found between urinary cadmium, lead and zinc concentrations, and urinary β2-M levels and NAG activities of the exposed group. A statistically significant increase was also observed for urinary NAG activity in exposed workers who had urinary cadmium concentrations > 2 μg g?1 creatinine. However, in the same exposed group, the increment of β2-M was not statistically significant. In conclusion, the present study thus confirms the earlier observations and may suggest the notion that the urinary NAG seems to be a more sensitive indicator than urinary β2-M level in early stages of renal injury of moderately cadmium co-exposure with lead and zinc even at urinary cadmium concentration as low as 2 μg g?1 creatinine. When the earlier studies on the irreversibility of cadmium-induced tubular dysfunction and the present results were taken into consideration, the present health-based biological limit proposed by the WHO (5 μg g?1 creatinine) seems to be high for the occupational exposure to cadmium.  相似文献   
33.
刘鹏  钱冬萌  王桐梅  宋旭霞  王斌 《生物磁学》2013,(25):4921-4924
目的:肾移植患者由于术前透析及术后服用免疫抑制剂,显著增加了人巨细胞病毒(Humancytomegalovirus,HCMV)原发感染和潜伏感染被激活的机会。观察HCMV感染情况与血T淋巴细胞亚群及肾功能的变化,以探讨其相关性及临床意义。方法:跟踪收集40例肾移植患者术前、术后血标本,应用RT-PCR技术检测HCMV,流式细胞术检测淋巴细胞亚群,结合肾功能判断是否发生急性排斥或移植肾功能恢复延迟。结果:肾移植术后HCMV感染率为52.5%,10例出现症状性感染(25%),出现阳性时间35.7±15.3天。症状性感染组CD3-bCD4+的水平和CD4+/CD8+的比值较无活动性感染组和正常对照组均降低,CD8+水平较其他组升高,差异有显著性意义(P〈0.05)。无症状性活动感染者与无活动性感染者各指标比较差异无显著性。活动性感染组急性排斥或移植肾功能恢复延迟发生8例(38.1%),无活动性感染组发生1例(5.2%),差异具有统计学意义(x^2=6.15,P〈0.05)。结论:肾移植术后HCMV感染能显著引起T淋巴细胞亚群变化,尤其是CD4+/CD8+。并与急性排斥或移植肾功能恢复延迟密切相关联,在其发生发展中可能起着重要的作用。三者相互联系、相互作用、互为因果,对进一步机制的研究及临床诊断治疗、预后方面有一定意义。  相似文献   
34.

Aims

Hypertension is associated with the impairment of renal cyclooxygenase (COX) activity, which regulates vascular tone, salt and water balance and renin release. We aimed to evaluate the functional role of COX isoforms in kidneys isolated from spontaneously hypertensive rats (SHR) after α1-adrenoceptor (α1-AR) stimulation.

Main methods

Male six-month-old SHR and normotensive Wistar-Kyoto rats (WKY) were used. The kidneys were isolated to measure perfusion pressure and COX-1- or COX-2-derived prostanoids in response to α1-AR activation.

Key findings

The basal perfusion pressure was higher in SHR kidneys compared with WKY kidneys (95 ± 11 vs. 68 ± 6 mm Hg, P < 0.05). Phenylephrine induced a greater vasopressor response in SHR kidneys (EC50 of 1.89 ± 0.58 nmol) than WKY kidneys (EC50 of 3.30 ± 0.54 nmol, P < 0.05 vs. SHR). COX-1 inhibition decreased the α1-AR-induced vasoconstrictor response in WKY but did not affect SHR response, while COX-2 inhibition diminished the response in SHR. Both basal prostacyclin (PGI2) and thromboxane A2 (TxA2) values were higher in SHR kidney perfusates (P < 0.05) and were reduced by COX-1 and COX-2 inhibitors in both strains. Furthermore, phenylephrine increased PGI2 through COX-2 in WKY and through COX-1 in SHR, but the agonist did not significantly modify TxA2 in both strains.

Significance

The data suggest that COX-1contributes to vasoconstrictor effects in WKY kidneys and that COX-2 has the same effect in SHR kidneys. The results also suggest that basal release of COX-2-derived vasoconstrictor prostanoids is involved in renal vascular hypersensitivity in SHR.  相似文献   
35.
The peripheral dopaminergic system plays a crucial role in blood pressure regulation through its actions on renal hemodynamics and epithelial ion transport. The dopamine D5 receptor (D5R) interacts with sorting nexin 1 (SNX1), a protein involved in receptor retrieval from the trans-Golgi network. In this report, we elucidated the spatial, temporal, and functional significance of this interaction in human renal proximal tubule cells and HEK293 cells stably expressing human D5R and in mice. Silencing of SNX1 expression via RNAi resulted in the failure of D5R to internalize and bind GTP, blunting of the agonist-induced increase in cAMP production and decrease in sodium transport, and up-regulation of angiotensin II receptor expression, of which expression was previously shown to be negatively regulated by D5R. Moreover, siRNA-mediated depletion of renal SNX1 in C57BL/6J and BALB/cJ mice resulted in increased blood pressure and blunted natriuretic response to agonist in salt-loaded BALB/cJ mice. These data demonstrate a crucial role for SNX1 in D5R trafficking and that SNX1 depletion results in D5R dysfunction and thus may represent a novel mechanism for the pathogenesis of essential hypertension.  相似文献   
36.
Expression of the receptor tyrosine kinase-like orphan receptor 2 (Ror2) has been identified in an increasing array of tumor types and is known to play a role as an important mediator of Wnt signaling cascades. In this study, we aimed to clarify Ror2 interactions with the Wnt pathways within the context of renal cell carcinoma (RCC). An examination of Ror2 expression in primary human RCC tumors showed a significant correlation with several Wnt signaling genes, including the classical feedback target gene Axin2. We provide evidence that Ror2 expression results in a partially activated state for canonical Wnt signaling through an increased signaling pool of β-catenin, leading to an enhancement of downstream target genes following Wnt3a stimulation in both renal and renal carcinoma-derived cells. Additionally, inhibition of low-density lipoprotein receptor-related protein 6 (LRP6) with either siRNA or dickkopf decreased the response to Wnt3a stimulation, but no change was seen in the increased β-catenin pool associated with Ror2 expression, suggesting that LRP6 cofactor recruitment is necessary for a Wnt3a-induced signal but that it does not participate in the Ror2 effect on β-catenin signaling. These results highlight a new role for Ror2 in conveying a tonic signal to stabilize soluble β-catenin and create a poised state of enhanced responsiveness to Wnt3a exogenous signals in RCC.  相似文献   
37.
Cilia in ciliated cells consist of protruding structures that sense mechanical and chemical signals from the extracellular environment. Cilia are assembled with variety molecules via a process known as intraflagellar transport (IFT). What controls the length of cilia in ciliated cells is critical to understand ciliary disease such as autosomal dominant polycystic kidney disease, which involves abnormally short cilia. But this control mechanism is not well understood. Previously, multiple tubular cysts have been observed in the kidneys of max-interacting protein 1 (Mxi1)-deficient mice aged 6 months or more. Here, we clarified the relationship between Mxi1 inactivation and cilia disassembly. Cilia phenotypes were observed in kidneys of Mxi1-deficient mice using scanning electron microscopy to elucidate the effect of Mxi1 on renal cilia phenotype, and cilia disassembly was observed in Mxi1-deficient kidney. In addition, genes related to cilia were validated in vitro and in vivo using quantitative PCR, and Ift20 was selected as a candidate gene in this study. The length of cilium decreased, and p-ERK level induced by a cilia defect increased in kidneys of Mxi1-deficient mice. Ciliogenesis of Mxi1-deficient mouse embryonic fibroblasts (MEFs) decreased, and this abnormality was restored by Mxi1 transfection in Mxi1-deficient MEFs. We confirmed that ciliogenesis and Ift20 expression were regulated by Mxi1 in vitro. We also determined that Mxi1 regulates Ift20 promoter activity via Ets-1 binding to the Ift20 promoter. These results indicate that inactivating Mxi1 induces ciliary defects in polycystic kidney.  相似文献   
38.
目的:探究肾静态显像(99m Tc-DMSA)在上尿路感染诊断工作中的应用意义。方法:选取2012年7月至2015年2月我院收治的60例上尿路感染患儿为研究对象,均行肾静态显像检查,并与B超检查结果进行对比分析。结果:肾静态显像提示:60例上尿路感染患儿中,肾脏损害占90.00%,其中8例肾疤痕形成,46例急性肾盂肾炎改变,6例正常;在肾脏病变范围上,≤2岁年龄组患儿较2岁年龄组患儿更为广泛,且前者程度更为严重。B超提示肾脏损害占26.67%,其中18例尿路感染反复发作;16例(26.67%)伴有急性肾盂肾炎改变,未检出肾疤痕。B超诊断上尿路感染的阳性率达26.67%,肾静态显像检查诊断上尿路感染的阳性率为90.00%,两者比较差异有显著性(P0.05)。结论:99mTc-DMSA在上尿路感染诊断工作中具有重要的应用意义,可明确病变性质、程度及范围,并可随访病变转归,指导临床治疗,属于上尿路感染的实验室补充性指标,值得临床积极推广。  相似文献   
39.
Kidney transplantation is the treatment of choice for patients suffering from end-stage renal disease. It offers better life expectancy and higher quality of life when compared to dialysis. Although the last few decades have seen major improvements in patient outcomes following kidney transplantation, the increasing shortage of available organs represents a severe problem worldwide. To expand the donor pool, marginal kidney grafts recovered from extended criteria donors (ECD) or donated after circulatory death (DCD) are now accepted for transplantation. To further improve the postoperative outcome of these marginal grafts, research must focus on new therapeutic approaches such as alternative preservation techniques, immunomodulation, gene transfer, and stem cell administration.Experimental studies in animal models are the final step before newly developed techniques can be translated into clinical practice. Porcine kidney transplantation is an excellent model of human transplantation and allows investigation of novel approaches. The major advantage of the porcine model is its anatomical and physiological similarity to the human body, which facilitates the rapid translation of new findings to clinical trials. This article offers a surgical step-by-step protocol for an autotransplantation model and highlights key factors to ensure experimental success. Adequate pre- and postoperative housing, attentive anesthesia, and consistent surgical techniques result in favorable postoperative outcomes. Resection of the contralateral native kidney provides the opportunity to assess post-transplant graft function. The placement of venous and urinary catheters and the use of metabolic cages allow further detailed evaluation. For long-term follow-up studies and investigation of alternative graft preservation techniques, autotransplantation models are superior to allotransplantation models, as they avoid the confounding bias posed by rejection and immunosuppressive medication.  相似文献   
40.
目的:探讨后腹腔镜下肾部分切除术对肾癌患者肾功能以及近远期预后的影响。方法:回顾性分析2012年1月~2017年8月在我院接受手术治疗的肾癌患者92例,根据不同手术治疗方法分为观察组(n=48)和对照组(n=44)。对照组行传统开放手术治疗,观察组行后腹腔镜下肾部分切除术。对比两组患者术前、术后血清肌酐(Cr)、血尿素氮(BUN)、β2-微球蛋白(β2-MG)、C反应蛋白(CRP)、白细胞介素-6(IL-6)水平的变化,术后1年、3年、5年生存率及切口感染、肺部感染、腹部疼痛、肾周血肿等并发症的发生情况。结果:观组患者手术时间、术后胃肠功能恢复时间、住院时间均明显短于对照组(P0.05),术中出血量、术后引流管引流量均显著低于对照组(P0.05)。术后1个月、术后2个月,两组患者血清Cr、BUN、β2-MG表达水平均较治疗前上升,且观察组以上指标显著低于对照组(P0.05)。术后,两组患者血清CRP、IL-6水平虽有升高,但观察组以上指标明显低于对照组(P0.05)。两组患者术后3年、5年的生存率均较术前下降,但观察组均分别高于对照组(P0.05)。术后,两组患者均有出现切口感染、肺部感染、腹部疼痛、肾周血肿等并发症,观察组总发生率(10.42%)明显低于对照组(29.54%,P0.05)。结论:后腹腔镜下肾部分切除术治疗肾癌患者可缩短患者的住院时间,对肾功能影响小,明显提高患者术后3年、5年生存率,且安全性更高。  相似文献   
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