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101.
Gingko biloba leaves have been used as herbal medicine in China for 5000 years, and the standardized leaf extract (GB-STE) has some beneficial effects in the treatment of age-related, cardiovascular, and neurological diseases. The aim of this study was to investigate the renoprotective effects of the Gingko biloba extract (GbE) against the toxicity of a single and relatively low dose of carbon tetrachloride (CCl4). In male adult Wistar rats, we determined the urine flux, the concentration of total proteins in urine, the concentration of glucose in urine, and the concentration of malondialdehyde (MDA) in renal cortex as well as two markers of renal function (clearance of inulin and p-aminohippurate); we also compared the histological lesions caused by CCl4. Carbon tetrachloride increased the urinary concentration of total proteins, and the renal concentration of MDA; however, it did not modify the urine flux, urinary concentration of glucose, nor the inuline or the p-aminohipurate clearances. Morphologically, CCl4 generated some tubular damage that was more intense in the inner cortex of kidneys. The GbE extract counteracted the effects of CCl4 on the concentration of total proteins in urine, the concentration of renal MDA, and the renal histological changes. In conclusion the main toxic effects produced by CCl4 were prevented by the GbE, probably due to their antioxidant properties and the inhibition of the main P450 isoenzyme (CYP2E1) that metabolize CCl4.  相似文献   
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Safflower (Carthamus tinctorius L.) is a traditional medicinal and edible herb with a long history of use in China. In this study, a model of hepatotoxicity induced by carbon tetrachloride (CCl4) in mice was used to investigate the hepatoprotective effects of kaempferol 3-O-rutinoside (K-3-R) and kaempferol 3-O-glucoside (K-3-G), two kaempferol glycosides isolated from C. tinctorius L. K-3-R and K-3-G, at doses of 200 mg/kg and 400 mg/kg, were given orally to male mice once/d for 7 days before they received CCl4 intraperitoneally. Our results showed that K-3-R and K-3-G treatment increased the level of total protein (TP) and prevented the CCl4-induced increases in serum aspartate aminotransferase (AST), serum alkaline phosphatase (ALP), and hepatic malondialdehyde (MDA) levels. Additionally, mice treated with K-3-R and K-3-G had significantly restored glutathione (GSH) levels and showed normal catalase (CAT) and superoxide dismutase (SOD) activities, compared to CCl4-treated mice. K-3-R and K-3-G also mitigated the CCl4-induced liver histological alteration, as indicated by histopathological evaluation. These findings demonstrate that K-3-R and K-3-G have protective effects against acute CCl4-induced oxidative liver damage.  相似文献   
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Objective: The purpose of this study was to examine the vasoreactivity in retina and choroid of the healthy eyes in response to experimentally altered partial arterial pressure of carbon dioxide (PaCO2) using a non-invasive technique, spectral domain optical coherence tomography (SD-OCT).

Materials and methods: The study included non-smoking participants between 18 and 35 years of age, having visual acuity of 20/20 and with no systemic and ocular diseases. At baseline, the participants breathed room air (normocapnia). Hypocapnia was created with the help of hyperventilation; for this, the participants were instructed to draw deep and quick breaths, resulting one breathing cycle per 2?s. To create hypercapnia subjects rebreathed from a 5?l bag at least 3?min. Choroidal thickness and retinal artery diameter were measured at baseline, and hyperventilation and rebreathing conditions by SD-OCT.

Results: Twenty eyes of 20 healthy subjects were included in this study. Their mean age was 24.90?±?5.32 years. Hyperventilation caused a significant reduction in choroidal thickness, compared with baseline, at all points; whereas rebreathing caused no significant change at all points. The mean diameters of the arteries were 151.80?±?7.88?μm, with a significant decline to 148.90?±?7.25?μm at hyperventilation condition and a significant increase to 153.50?±?7.88?μm at rebreathing condition (p?=?0.018, p?=?0.043, respectively).

Conclusion: This study demonstrated that, SD-OCT was a useful tool in measuring the ocular vascular response under hypercapnia and hypocapnia conditions. These findings may be helpful for further understanding the physiological nature of ocular blood flow and this preliminary study provides a basis for future studies.  相似文献   
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《Seminars in immunology》2015,27(3):227-233
There are numerous gaseous substances that can act as signaling molecules, but the best characterized of these are nitric oxide, hydrogen sulfide and carbon monoxide. Each has been shown to play important roles in many physiological and pathophysiological processes. This article is focused on the effects of these gasotransmitters in the context of inflammation. There is considerable overlap in the actions of nitric oxide, hydrogen sulfide and carbon monoxide with respect to inflammation, and these mediators appear to act primarily as anti-inflammatory substances, promoting resolution of inflammatory processes. They also have protective and pro-healing effects in some tissues, such as the gastrointestinal tract and lung. Over the past two decades, significant progress has been made in the development of novel anti-inflammatory and cytoprotective drugs that release of one or more of these gaseous mediators.  相似文献   
108.
As crucial small regulatory molecules, serum microRNAs (miRNAs) have been widely identified as potential noninvasive biomarkers. To survey and identify serum miRNAs associated with workers who had experienced injury to their nerve system from carbon disulfide (CS2), we profiled abnormally expressed miRNAs using the microarray technique and further performed qRT-PCR validation in case and control samples (n=20). Microarray profiling in pooled RNA samples showed that many miRNAs in workers exposed to CS2 were aberrantly expressed. Based on control samples exposed to CS2, a great amount of abnormal miRNAs, including some miRNA gene clusters and families, were obtained from microarray datasets. Most of deregulated miRNAs were up-regulated, and almost all miRNAs showed consistent expression patterns between workers with different numbers of damaged nerve fibers. Functional enrichment analysis suggested that these abnormal miRNAs showed versatile roles by contributing to multiple biological processes. Some aberrantly expressed miRNAs were characterized as miRNA gene clusters or families, and they always showed consistent expression patterns. miR-150 and miR-30a were selected to be further validated by qRT-PCR as up-regulated species, and they could discern case samples from control samples. miR-150 and miR-30a may be potential noninvasive biomarkers for a damaged nervous system.  相似文献   
109.
目的:探索 microRNA 在四氯化碳(CCl4)诱导的大鼠纤维化肝组织中的差异表达及其意义。方法采用 microR-NA 高通量测序分析技术检测对照组(n=10)与模型组(n=10)肝脏组织 microRNA 表达,对差异 microRNA 进行靶基因预测,对靶基因进行基因本(GO)分析、pathway 分析。结果对照组与模型组间筛选出37个差异 microRNA,上调29个,下调8个;从microRNA-基因网络图中发现关键上调为 miR-184、miR-10b-5p、miR-199a-3p 等;关键下调为 miR-200b-3p、miR-199a-5p、miR-125b-5p 等。结论模型组 microRNA 表达谱变化明显,肝纤维化的形成与 microRNA 调控细胞增殖、凋亡、细胞周期等有关。  相似文献   
110.
目的:探讨蓝莓对四氯化碳(CCl4)所致急性肝损伤大鼠肝组织γ‐谷氨酰半胱氨酸合成酶(γ‐GCS)催化亚基(GCLC)mRNA及蛋白表达的影响。方法将50只雄性Wistar大鼠分为5组,即空白组、模型组、蓝莓汁低剂量预防组(蓝低组,10.0g/kg)、蓝莓汁高剂量预防组(蓝高组,20.0g/kg)、联苯双酯预防组(联苯双酯组,0.15g/kg),每组10只,连续灌胃7d,1次/天,其后用CCl4复制大鼠急性肝损伤模型。光镜下观察大鼠肝脏病理学变化,全自动生化分析仪测定血清丙氨酸氨基转移酶(ALT)及天冬氨酸氨基转移酶(AST)活性,酶联免疫吸附法检测肝匀浆中丙二醛(MDA)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、还原型谷胱甘肽(GSH)活力及含量,分别采用反转录PCR(RT‐PCR)、免疫组织化学法、Westernblot检测大鼠肝组织中GCLCmRNA及蛋白表达。结果蓝低组、蓝高组和联苯双酯组大鼠肝细胞变性及坏死程度显著轻于模型组(P<0.05),血清ALT、AST及肝匀浆MDA均显著低于模型组(P<0.01),而肝匀浆CAT、SOD、GSH均显著高于模型组(P<0.01),肝组织GCLCmR‐NA及蛋白表达均显著高于模型组(P<0.01)。3组相比,蓝高组与联苯双酯组效果相似,略优于蓝低组。结论蓝莓对CCl4诱导的大鼠急性肝损伤有一定预防作用,可能与上调大鼠肝脏GCLC表达,减轻氧化应激性肝损伤有关。  相似文献   
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