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991.
Shuo Yang Yizhao Chen Xinqing Deng Weiping Jiang Bing Li Zhenghao Fu Mouxuan Du Rui Ding 《Journal of molecular neuroscience : MN》2013,51(2):352-363
Hemoglobin (Hb) released from extravasated erythrocytes may have a critical role in the process of blood–brain barrier (BBB) disruption and subsequent edema formation after intracerebral hemorrhage (ICH). Excessive nitric oxide (NO) production synthesized by nitric oxide synthase (NOS) has been well documented to contribute to BBB disruption. However, considerably less attention has been focused on the role of NO in Hb-induced BBB disruption. This study was designed to examine the hypothesis that Hb-induced NOS overexpression and excessive NO production may contribute to the changes of tight junction (TJ) proteins and subsequent BBB dysfunction. Hemoglobin was infused with stereotactic guidance into the right caudate nucleus of male Sprague Dawley rats. Then, we investigated the effect of Hb on the BBB permeability, changes of TJ proteins (claudin-5, occludin, zonula occludens-1 (ZO-1), and junctional adhesion molecule-1 (JAM-1)), iron deposition, expression of inducible NOS (iNOS) and endothelial NOS (eNOS), as well as NO production. Hb injection caused a significant increase in BBB permeability. Significant reduction of claudin-5, ZO-1, and JAM-1 was observed after Hb injection as evidenced by PCR and immunofluorescence. After a decrease at early stage, occludin showed a fivefold increase in mRNA level at 7 days. Significant iron deposition was detectable from 48 h to 7 days in a time-dependent manner. The iNOS and eNOS levels dramatically increased after Hb injection concomitantly with large quantities of NO released. Furthermore, enhanced iNOS or eNOS immunoreactivity was co-localized with diffused or diminished claudin-5 staining. We concluded that overexpressed NOS and excessive NO production induced by Hb may contribute to BBB disruption, which may provide an important potential therapeutic target in the treatment of ICH. 相似文献
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993.
Tzu-Fang Wang Someswara Rao Kosuru Shu-Chun Yu Yung-Chi Chang Hsin-Yu Lai Yu-Lun Chang Kuo-Hui Wu Shangwu Ding Hsuan-Ying Chen 《RSC advances》2020,10(67):40690
Using TiOiPr4 with a pyrazole ligand for one-pot LA polymerization improved catalytic activity compared with using TiOiPr4 only. At 60 °C, TiOiPr4 with furPz exhibited a higher catalytic activity (approximately 3-fold) than TiOiPr4. At room temperature, TiOiPr4 with BuPz exhibited a higher catalytic activity (approximately 17-fold) than TiOiPr4. High molecular mass PLA (MnGPC = 51 100, and Đ = 1.10) could be produced by using TiOiPr4 with furPz in melt polymerization ([TiOiPr4] : [furPz] = 1000 : 1 : 1 at 100 °C, 240 min). The crystal structure of MePz2Ti2OiPr7 revealed the cooperative activation between two Ti atoms during LA polymerization.Using TiOiPr4 with a pyrazole ligand for one-pot LA polymerization improved catalytic activity compared with using TiOiPr4 only. 相似文献
994.
Ru Li Zhi-li Li Ya-ping Chen Wei-quan Bu Wen-bo Ding Bing Yang Chun-fei Wang Liang Ma Xiao-bin Jia Liang Feng 《RSC advances》2020,10(65):39385
The purpose of this study is to explore the intrinsic reasons for the superiority of the salt-made geoherb Alisma orientale via comparing the content of various components of the salt-made geoherb Alisma orientale. The effects of “diuresis and diffusing dampness” using salt-made Alisma orientale from seven different origins were investigated through pharmacodynamic experiments in vivo and in vitro. The results indicated that salt-made Alisma orientale from different origins had diuretic efficacy; this was demonstrated by the significant increase in the volume of rat urine, the concentration of Na+, K+, and Cl− in the urine, and the significant decrease in the levels of AQP-2 in rat renal medulla and HK-2 cells. It was also revealed that the diuretic effect of salt-made Alisma orientale from Fujian Province is stronger than those from other provinces. Moreover, the main components and their proportions in the salt-made Alisma orientale samples were further analyzed via principal component analysis. The results showed that alisol A 24-acetate, alisol B, and 23-acetyl alisol B are the main components of salt-made Alisma orientale, and the optimal structural ratio of alisol A 24-acetate, alisol B, and 23-acetyl alisol B was found to be 5.38 : 14.34 : 11.31 via optimizing the ratios of the three main components. It is worth noting that the optimal ratio of the three main components after optimization is the closest to the ratio of the three main components in salt-made Alisma orientale from Fujian Province. This paper reveals the “mystery” of the content ratio of the main active components and its effect on the efficacy, and showed that the proportional relationship between the content of multiple components is the key to their interactions. Therefore, this method of evaluating the quality of salt-made Alisma orientale is obviously reliable, and this study lays the foundations for quality evaluation of salt-made Alisma orientale and other herb slices.The purpose of this study is to explore the intrinsic reasons for the superiority of the salt-made geoherb Alisma orientale via comparing the content of various components of the salt-made geoherb Alisma orientale. 相似文献
995.
An-liu Zhang Shun-fang Tang Yue Yang Chang-zhe Li Xue-jiao Ding Hua Zhao Jun-hua Wang Guang-hong Yang Jun Li 《Journal of applied toxicology : JAT》2020,40(12):1661-1672
Long-term arsenic exposure is a worldwide public health problem that causes serious harm to human health. The liver is the main target organ of arsenic toxicity; arsenic induces disruption of the DNA damage repair pathway, but its mechanisms remain unclear. In recent years, studies have found that epigenetic mechanisms play an important role in arsenic-induced lesions. In this study, we conducted experiments in vitro using normal human liver cells (L-02) to explore the mechanism by which the histone demethylase JHDM2A regulates H3K9 dimethylation (me2) in response to arsenic-induced DNA damage. Our results indicated that arsenic exposure upregulated the expression of JHDM2A, downregulated global H3K9me2 modification levels, increased the H3K9me2 levels at the promoters of base excision repair (BER) genes (N-methylpurine-DNA glycosylase [MPG], XRCC1 and poly(ADP-ribose)polymerase 1) and inhibited their expression levels, causing DNA damage in cells. In addition, we studied the effects of overexpression and inhibition of JHDM2A and found that JHDM2A can participate in the molecular mechanism of arsenic-induced DNA damage via the BER pathway, which may not be involved in the BER process because H3K9me2 levels at the promoter region of the BER genes were unchanged following JHDM2A interference. These results suggest a potential mechanism by which JHDM2A can regulate the MPG and XRCC1 genes in the process of responding to DNA damage induced by arsenic exposure and can participate in the process of DNA damage repair, which provides a scientific basis for understanding the epigenetic mechanisms and treatments for endemic arsenic poisoning. 相似文献
996.
997.
Pharmaceutical Research - The discovery of nano drug delivery system has rendered a great hope for improving cancer therapy. However, there are some inevitable obstacles that constrain its... 相似文献
998.
999.
1000.
目的 探讨维持性血液透析终末期肾病(end stage renal disease,ESRD)患者肠道菌群的特点。方法 收集维持性血液透析的稳定ESRD患者和健康对照组受试者各22例粪便样本,提取样本DNA,进行16S rRNA基因测序,对肠道菌群的分布情况进行分析。结果 (1)维持性血液透析ESRD组观察到的各样品微生物物种量、物种多样性较健康对照组低,物种多样性在18~44岁组有统计学差异;(2)两组在纲、目、科、属、种分类水平上分别发现2、4、9、29、28个相对丰度有统计学差异的物种(P<0.05); 其中Negatibicutes纲、粪球菌属-3相对丰度维持性血液透析ESRD组低于健康对照组,而丹毒丝纲、目、科、属、种水平相对丰度维持性血液透析ESRD组高于健康对照组;(3)通过KEGG代谢途径的差异分析,推测两组间有3个存在统计学差异的代谢途径(P<0.05),其中与碳水化合物代谢途径相关基因在健康对照组粪便样品中显著富集,而与细胞运动性及药物耐药途径相关基因在维持性血液透析ESRD组粪便样品中显著富集。结论 维持性血液透析ESRD组患者肠道微生物群落多样性降低,与健康对照组比较在微生物群落相对丰度、KEGG功能预测相关基因代谢途径上存在差异。 相似文献