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31.
Cathryn M. Kolka 《Clinical and experimental pharmacology & physiology》2020,47(1):168-175
The endocrine system relies on the vasculature for delivery of hormones throughout the body, and the capillary microvasculature is the site where the hormones cross from the blood into the target tissue. Once considered an inert wall, various studies have now highlighted the functions of the capillary endothelium to regulate transport and therefore affect or maintain the interstitial environment. The role of the capillary may be clear in areas where there is a continuous endothelium, yet there also appears to be a role of endothelial cells in tissues with a sinusoidal structure. Here we focused on the most common endocrine disorder, diabetes, and several of the target organs associated with the disease, including skeletal muscle, liver and pancreas. However, it is important to note that the ability of hormones to cross the endothelium to reach their target tissue is a component of all endocrine functions. It is also a consideration in organs throughout the body and may have greater impact for larger hormones with target tissues containing a continuous endothelium. We noted that the blood levels do not always equal interstitial levels, which is what the cells are exposed to, and discussed how this may change in diseases such as obesity and insulin resistance. The capillary endothelium is, therefore, an essential and understudied aspect of endocrinology and metabolism that can be altered in disease, which may be an appropriate target for treatment. 相似文献
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《Annals of hepatology》2020,19(2):190-196
Introduction and objectivesZinc deficiency has been associated with poor prognosis in chronic liver disease. This systematic review and meta-analysis aimed to evaluate the role of zinc supplementation in the management of chronic liver diseases.Materials and methodsWe searched MEDLINE, LILACS, EMBASE, and Cochrane CENTRAL databases from inception to August 2018. We included randomized controlled trials evaluating adult patients with chronic liver disease of any etiology receiving zinc supplementation. Studies with other designs or evaluating chronic conditions other than liver disease were excluded. Two reviewers independently screened and extracted data from eligible studies. Study quality was assessed using the Cochrane Collaboration's tool for assessing risk of bias in randomized studies.ResultsOf 1315 studies screened, 13 were included. Six assessed chronic hepatitis C treatment, with a relative risk of 0.83 indicating no protective effect of zinc supplementation on the improvement of sustained virological response. Three evaluated response to hepatic encephalopathy treatment, with a relative risk of 0.66 indicating a favorable effect of zinc supplementation on clinical improvement of this condition. Of four studies evaluating the management of cirrhosis, two analyzed the effect of zinc supplementation on serum albumin levels, with no statistical difference between zinc and placebo groups.ConclusionsClinical trials assessing zinc supplementation in liver diseases do not show benefits in terms of clinical improvement or disease halting. There are possible benefits of zinc supplementation on hepatic encephalopathy, however, this is based on limited evidence. This research question is still open for evaluation in larger, well-designed, clinical trials. 相似文献
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A. Nakao H. Toyokawa A. Tsung M. A. Nalesnik D. B. Stolz J. Kohmoto A. Ikeda K. Tomiyama T. Harada T. Takahashi R. Yang M. P. Fink K. Morita A. M. K. Choi N. Murase 《American journal of transplantation》2006,6(10):2243-2255
Carbon monoxide (CO), a byproduct of heme catalysis, was shown to have potent cytoprotective and anti-inflammatory effects. In vivo recipient CO inhalation at low concentrations prevented ischemia/reperfusion (I/R) injury associated with small intestinal transplantation (SITx). This study examined whether ex vivo delivery of CO in University of Wisconsin (UW) solution could ameliorate intestinal I/R injury. Orthotopic syngenic SITx was performed in Lewis rats after 6 h cold preservation in control UW or UW that was bubbled with CO gas (0.1-5%) (CO-UW). Recipient survival with intestinal grafts preserved in 5%, but not 0.1%, CO-UW improved to 86.7% (13/15) from 53% (9/17) with control UW. At 3 h after SITx, grafts stored in 5% CO-UW showed improved intestinal barrier function, less mucosal denudation and reduced inflammatory mediator upregulation compared to those in control UW. Preservation in CO-UW associated with reduced vascular resistance (end preservation), increased graft cyclic guanosine monophosphate levels (1 h), and improved graft blood flow (1 h). Protective effects of CO-UW were reversed by ODQ, an inhibitor of soluble guanylyl cyclase. In vitro culture experiment also showed better preservation of vascular endothelial cells with CO-UW. The study suggests that ex vivo CO delivery into UW solution would be a simple and innovative therapeutic strategy to prevent transplant-induced I/R injury. 相似文献
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氧化砷对小鼠腹水型肝癌细胞的作用 总被引:2,自引:0,他引:2
目的 :研究氧化砷对移植性腹水型肝癌细胞的抗癌作用。方法 :肝癌细胞 (1 8× 10 7)接种入小鼠腹腔。对照组注射NS(0 8mL) ,余组用氧化砷 (1,2 ,3μmol/L)腹腔注射 ,每日 1次 ,共 10日。结果 :第 10天腹水细胞计数 ,1,2和 3μmol/L组瘤细胞锐减 (P <0 0 5 ) ,但第 16天腹水肿瘤细胞急骤增加。结论 :氧化砷对腹水肿瘤细胞有暂时抑制作用。 相似文献
40.
非胰岛素依赖型糖尿病患者血清唾液酸的改变 总被引:2,自引:0,他引:2
测定20例NIDDM伴有心脑血管病变的患者、20例单纯NIDDM患者的血清唾液酸(SA)水平,并与20例正常人进行比较。结果发现所有NIDDM患者的血清SA水平均显著增高(P<0.01),其中伴有心脑血管疾病患者的血清SA水平显著高于单纯NIDDM患者(P<0.05),同时血清SA水平与血清胰岛素及C肽水平、收好压之间存在相关。提示血清SA水平与NIDDM患者的心脑血管疾病关系密切,可能是心脑血管并发症发生的一个危险因素。 相似文献