Effect of Oxidation on the Activity of Angiotensin Converting Enzyme in the Rat Kidney,Heart, and Brain

ABSTRACT

The activities of angiotensin converting enzyme(ACE) in crude extracts of renal cortex, heart and brain of the rat were increased when the oxidizing agent diamide was added to the extracts and then the activity determined. By pretreatment of the extracts with 10 mM diamide, the activities of ACE in the extracts of heart, brain and renal cortex were about 500, 290 and 240 % of the control value, determined without the diamide-pretreatment, respectively. In the lung and aorta, increments in the activity after oxidation were less than 20 % of the control. No such increase was observed in the plasma. Similar results were obtained when the extracts were exposed to O₂. The activity was also increased by oxidation with diamide and O₂, when an extract of the human renal cortex was used. Thus, the activity of ACE in the kidney, heart and brain can be increased by oxidation.     

Promoting Exercise Self-Efficacy With an Exergame

A new generation of exercise video games (exergames) shows promise as a tool to motivate and engage users in physical activity. However, little research has been conducted to examine whether exergames work equally well across diverse populations and contexts. Therefore, in the present study, the authors investigated the effects of an individual psychological difference factor and a specific contextual factor on the exercise experience using an exergame. They used the objective self-awareness theory as the theoretical underpinning. In a 2 (seeing the image of self on screen: seeing oneself vs. not seeing oneself) × 2 (body image dissatisfaction: low vs. high) between-subjects design experiment, the authors found significant interaction effects showing that the feature of seeing the image of self on screen provided by the exergame works positively for individuals with low body image dissatisfaction, yet works negatively for individuals with high body image dissatisfaction. The finding of the present study has significant implications for health professionals and individuals who use the new generation of exergames for physical activities.     

(−)-Epigallocatechin-3-gallate inhibits voltage-gated proton currents in BV2 microglial cells

(?)-Epigallocatechin-3-gallate (EGCG), the principal constituent of green tea, protects neurons from toxic insults by suppressing the microglial secretion of neurotoxic inflammatory mediators. Voltage-gated proton channels are expressed in microglia, and are required for NADPH oxidase-dependent reactive oxygen species generation. Brain damage after ischemic stroke is dependent on proton channel activity. Accordingly, we examined whether EGCG could inhibit proton channel function in the murine microglial BV2 cells. EGCG potently inhibited proton currents with an IC₅₀ of 3.7 μM. Other tea catechins, (?)-epigallocatechin, (?)-epicatechin and (?)-epicatechin-3-gallate, were far less potent than EGCG. EGCG did not change the kinetics of proton currents such as the activation and the deactivation time constants, the reversal potential and the activation voltage, suggesting that the gating process of proton channels were not altered by EGCG. EGCG is known to disturb lipid rafts by sequestering cholesterol. However, neither extraction of cholesterol with methyl-β-cyclodextrin or cholesterol supplementation could reverse the EGCG inhibition of proton currents. In addition, the EGCG effect was preserved in the presence of the cytoskeletal stabilizers paclitaxel and phalloidin, phosphatase inhibitors, the antioxidant Trolox, superoxide dismutase or catalase. The proton channel inhibition can be a substantial mechanism for EGCG to suppress microglial activation and subsequent neurotoxic events.     

The Fruits of Xanthium sibiricum Patr: A Review on Phytochemistry, Pharmacological Activities, and Toxicity

In recent years, drug development and research have gradually shifted from chemicalsynthesisto biopharmaceutical and natural drugs. Natural medicines, such as traditional Chinese medicine, have been among the first studied because of their long medicinal history, simplicity, and the relatively low cost of research. Among them, Xanthii Fructus (XF) is famous for the treatment of sinusitis. In this article, the achievements of research on XF from 1953 to 2020 are systematically reviewed, focusing on the aspects of chemical constituents, pharmacological effects, clinical applications, toxicity and side effects, and processing methods. To date, there have been significant advancesin both the phytochemistry and pharmacology of XF. Some traditional uses have been validated and clarified in modern pharmacologicalstudies. However, its mechanism of action in the treatment of allergic diseases has not been satisfactorily explained. Further in vitro and in vivo studies are required to rationally develop new drugs and to elucidate the therapeutic potential of XF. A comprehensive evaluation of XF and an understanding of network pharmacology are also needed.     

应用TUR术治疗膀胱癌膀胱全切术后复发性尿道癌

目的：探讨膀胱癌行膀胱全切术后尿道复发的治疗方法.方法：回顾性分析膀胱癌行膀胱全切术患者216例,其中术后复发尿道癌15例（6.9％）,复发平均时间18（3-46）个月.15例患者术后因肉眼血尿（7例）、血性分泌物（3例）及排尿不畅（5例）再次就诊.均经尿道膀胱镜检查及尿道冲洗细胞学检查确诊.尿道镜活检报告为尿道尿路上皮癌,病理分期为Ta-T1.15例均行TUR术,术后辅以羟基喜树碱灌注治疗.结果：15例患者术后平均随访36（6-52）个月.其中12例患者健在,未见肿瘤复发及转移;1例术后14个月肿瘤复发,行全尿道切除＋尿液转流术,随访至今未见肿瘤再次复发及转移;1例术后8个月肿瘤复发,行全尿道切除＋阴道前壁、侧壁、子宫及附件切除＋盆腔淋巴结清扫术,术后9个月死于肿瘤多发转移;1例死于心肌梗死.结论：膀胱癌膀胱全切术后复发尿道癌可应用TUR术治疗,临床效果良好且生活质量较高.早期诊断与治疗是保证预后的关键.