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91.
The elevation of renal sympathetic nervous activity (SNA) is a possible cause of blood pressure (BP) elevation. Although a high-fat diet (FAT) often induces BP elevation in animals, the effect of FAT on renal SNA in animals is not consistent between studies. Thus, we compared the basal levels of efferent renal SNA and BP in FAT- or high-carbohydrate diet (CHO)-fed rats. Twenty-four male Sprague-Dawley rats were fed FAT (P/F/C=20/45/35% cal) or CHO (20/5/75) from 5 weeks of age. After 20-21 weeks of feeding, a 24-h urine sample was collected to measure sodium excretion. The next day, blood (0.2 ml) was withdrawn from a femoral artery, and basal efferent renal nerve discharges and mean arterial pressure (MAP) were recorded under anesthesia. Immediately after the experiment, abdominal (epididymal, perirenal and mesenteric) adipose tissues were dissected. Total abdominal fat weight was significantly greater in the FAT group than in the CHO group. The plasma level of leptin was significantly higher in the FAT group, but blood glucose and plasma insulin levels did not differ between the two groups. MAP and renal SNA were significantly higher in the FAT group. In addition, the ratio of urinary sodium excretion to dietary sodium intake was significantly lower in the FAT group than in the CHO group. The data suggest that the increased renal SNA may contribute to BP elevation in FAT-fed rats. The present study firstly demonstrated that renal SNA was elevated with FAT-related BP elevation.  相似文献   
92.
Time-dependent differences in adverse reactions and efficacy by a repeated administration of 1,25(OH)2 vitamin D3 (vit D, 0.3 microg/Kg/day for 12 weeks) were examined in 5/6 nephrectomized rats under a condition of 12-hour light-dark cycle. The 5/6 nephrectomy increased serum concentrations of phosphate, osteocalcin and PTH, and urinary excretions of phosphate and deoxypyridinoline (DPD) while the maneuver reduced serum Ca concentration and its urinary excretion. Animals with a dosing of the drug at 2 hours after light on (HALO) had more grade of hypercalcemia and hyperphosphatemia than those at 14 HALO. Reduction of serum intact PTH and increase of serum vit D were observed in both groups with a similar extent. Increase of osteocalcin by the drug was greater in 14 HALO trial. Urinary excretion of DPD was not influenced by the treatment. The increase in bone density of femur was greater in 14 HALO than in 2 HALO trials. These results suggest that adverse reactions of vit D were ameliorated and its efficacy was enhanced after the repeated dosing of the drug at 14 HALO. Time-dependent variation in the sensitivity of the drug to osteoblast was involved in the mechanism of these events, while the roles of pharmacokinetic alteration and renal response were small, if any.  相似文献   
93.
We aimed to determine the immunological effects of low doses of recombinant interleukin-2 (rIL-2) and recombinant interferon-α (rIFN-α) in patients bearing advanced renal cell carcinoma. Methods: Twenty-seven patients received therapeutic cycles consisting of subcutaneous rIL-2 for 5 days per week and intramuscular rIFN-α twice weekly, for 4 consecutive weeks. The cycle was repeated indefinitely at regular 4-month intervals, for all patients. rIL-2 (1 × 106 IU/m2) was administered every 12 h on days 1 and 2 and once a day on days 3–5 of each week; rIFN-α (1.8 × 106 IU/m2) was given on days 3 and 5. In the enrolled patients, total and differential white blood cell counts, phenotypic analysis of some lymphocyte subsets, and soluble IL-2 receptor (sIL-2R), were investigated before and after each of the first six cycles of therapy (about 24 months of follow-up). Results: The cycles of immunotherapy induced a significant increase of total lymphocytes (37%, P < 0.001), eosinophils (222%, P < 0.001), CD25+ cells (27%, P=0.004), sIL-2R (174%, P < 0.001) and natural killer (NK) cells (CD3-CD56+) (61%, P < 0.001); the subset that expresses CD56 with high density (CD56+ bright) expanded more (233%, P < 0.001) than the subset expressing the same marker with low density (CD56+ dimmer) (15%, P=0.043). Unlike the previous subsets, the treatment decreased significantly T-lymphocytes with NK cell marker (CD3+ CD56+) (28%, P=0.011). No significant differences of effectiveness were found among the subsequent treatment cycles, except for CD25+ cells and sIL-2R (P=0.036 and P=0.005, respectively): the increase induced by immunotherapy was maximum after the first cycle and decreased progressively thereafter. Conclusions: Long-term repeated cycles of low-dose immunotherapy induced repeated and significant expansion of one of the most important lymphocyte subsets for the non-MHC-restricted immune response to the tumour mass: CD3–CD56+ cells. Received: 8 November 2000 / Accepted: 11 January 2001  相似文献   
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王健  王君  应伟  王静  何帆 《现代生物医学进展》2015,15(31):6119-6121
目的:探讨连续肾脏替代治疗(CRRT)对脓毒症患者血清中肿瘤坏死因子alpha(TNF-alpha)、白介素-6(IL-6)和白介素-8(IL-8)的 影响。方法:将我院2013 年1 月-2014 年6 月间收治的80 例脓毒症患者随机分为观察组与对照组各40 例,两组患者均给予脓毒 症常规治疗,观察组另给予CRRT 治疗。观察比较两组患者治疗前1 天,治疗后24 h,72 h空腹静脉血TNF-alpha、IL-6、IL-8 水平。结 果:观察组治愈率为85.0%(34/40),明显高于对照组的55.0%(22/40),差异有统计学意义(P<0.05);治疗24h、72h 后两组患者 TNF-alpha、IL-6和IL-8 水平均明显下降,其中观察组下降更显著,差异均有统计学意义(P<0.05)。结论:CRRT 能有效降低脓毒症患 者血清中TNF-alpha、IL-6 和IL-8 水平,有助于对炎症反应的正向调节。  相似文献   
96.
目的:观察输尿管软镜下钬激光碎石术与经皮肾镜下钬激光碎石术治疗肾结石对患者肾功能影响。方法:选择本院于2012 年5 月-2015 年5 月收治的单发肾结石且结石直径均≤ 2 cm的患者180 例作为研究对象,根据配对分组法分为两组,每组90 例,A组采取输尿管软镜下钬激光碎石术治疗,B组采取经皮肾镜下钬激光碎石术治疗。分别于手术前后测定两组患者尿Kim-1 及血清NGAL、Cys-C水平,评估患者肾功能。结果:两组术前及术后6 h、12 h、24 h、72 h尿Kim-1 水平比较均无统计学差异(P>0. 05);A 组术后48 h尿Kim-1 水平显著低于B组(P<0.05)。两组术后6 h、12 h、24 h尿Kim-1 水平均高于术前(P<0.05)。两组术后 6 h、12 h、24 h、48 h、72 h血清NGAL水平均高于术前,P<0.05。两组患者术前2 h、术后6 h血清Cys-C 水平均无显著统计学差异 (P>0.05);术后12 h、24 h、48 h、72 h血清Cys-C 水平均A 组均高于B 组(P<0.05)。结论:输尿管软镜下钬激光碎石术与经皮肾镜 下钬激光碎石术治疗肾结石均对患者肾功能造成损伤,但输尿管软镜下钬激光碎石术对肾小球损伤更为严重,经皮肾镜下钬激 光碎石术对肾小管损伤较为严重,临床应注意。  相似文献   
97.
目的:探讨肾癌组织Nrf2 和HO_1 表达水平变化及其临床意义。方法:选择经手术切除肾癌组织标本42 例及正常肾组织42 例作为研究对象,42 例患者均未接受化疗或者放疗,采取免疫组织化SABC法测定Nrf2 和HO_1 表达水平,并进行统计学分析。 结果:Nrf2 及HO_1 于肾癌组织及正常肾组织均有不同程度表达,且主要表达于肿瘤细胞胞浆,肾癌组中Nrf2 阳性35 例 (83.3%),显著高于正常肾组织14例(33.3%),差异具有统计学意义,P<0.05。肾癌组HO_1 表达阳性31 例(73.8),显著高于正常 肾组织组15 例(35.7),差异具有统计学意义,P<0.05。肾癌组织Nrf2和HO_1 表达水平成正相关,r=0.536。结论:肾癌组织Nrf2 和 HO_1表达水平较正常组织更高,且两者之间呈正相关,表明Nrf2 和HO_1 在肾癌进展中起着重要作用。  相似文献   
98.
目的:分析利奈唑胺对肾功能不全G+患者血小板减少的关系。方法:回顾性分析92例应用利奈唑胺治疗的革兰阳性球菌感染患者的临床资料,根据是否伴有肾功能不全分为肾功能不全组(33例),正常组(59例),检测用药前、用药后血小板计数,观察停药后血小板计数恢复正常时间及不良反应发生情况。结果:肾功能不全组治疗后血小板计数显著低于治疗前及正常组(P0.01),正常组治疗前、后血小板计数比较无统计学意义(P0.05);肾功能不全组血小板减少发生率高于正常组(P0.05);停药后正常组血小板恢复正常时间短于肾功能不全组(P0.01);肾功能不全组血红蛋白下降率高于正常组(P0.05),其余不良反应发生率比较差异无统计学意义(P0.05)。结论:感染患者肾功能可影响利奈唑胺所致血小板减少发生率,肾功能不全患者在应用利奈唑胺时应定期监测血小板计数。  相似文献   
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100.

Background

Growing evidence suggests that epigenetic mechanisms of gene regulation may play a role in susceptibilities to specific toxicities and adverse drug reactions. MiRNAs in particular have been shown to be important regulators in cancer and other diseases and show promise as predictive biomarkers for diagnosis and prognosis. In this study, we characterized the global kidney miRNA expression profile in untreated male and female F344 rats throughout the life span. These findings were correlated with sex-specific susceptibilities to adverse renal events, such as male-biased renal fibrosis and inflammation in old age.

Methods

Kidney miRNA expression was examined in F344 rats at 2, 5, 6, 8, 15, 21, 78, and 104 weeks of age in both sexes using Agilent miRNA microarrays. Differential expression was determined using filtering criteria of ≥1.5 fold change and ANOVA or pairwise t-test (FDR <5%) to determine significant age and sex effects, respectively. Pathway analysis software was used to investigate the possible roles of these target genes in age- and sex-specific differences.

Results

Three hundred eleven miRNAs were found to be expressed in at least one age and sex. Filtering criteria revealed 174 differentially expressed miRNAs in the kidney; 173 and 34 miRNAs exhibiting age and sex effects, respectively. Principal component analysis revealed age effects predominated over sex effects, with 2-week miRNA expression being much different from other ages. No significant sexually dimorphic miRNA expression was observed from 5 to 8 weeks, while the most differential expression (13 miRNAs) was observed at 21 weeks. Potential target genes of these differentially expressed miRNAs were identified.

Conclusions

The expression of 56% of detected renal miRNAs was found to vary significantly with age and/or sex during the life span of F344 rats. Pathway analysis suggested that 2-week-expressed miRNAs may be related to organ and cellular development and proliferation pathways. Male-biased miRNA expression at older ages correlated with male-biased renal fibrosis and mononuclear cell infiltration. These miRNAs showed high representation in renal inflammation and nephritis pathways, and included miR-214, miR-130b, miR-150, miR-223, miR-142-5p, miR-185, and miR-296*. Analysis of kidney miRNA expression throughout the rat life span will improve the use of current and future renal biomarkers and inform our assessments of kidney injury and disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s13293-014-0019-1) contains supplementary material, which is available to authorized users.  相似文献   
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