Antioxidant and lipid lowering activities of Indian black tea

Indian black tea; CTC leaf and dust, produced by Tata Tea Limited, Kolkata, (India) was studiedin vitro as potential scavenger of oxygen free radicals. Super oxide anions were generated in a system containing xanthine—xanthine oxidase (enzymic system) and by NADH- phenozine methosulphate (non enzymic system). Anions were assayed in terms of uric acid formation and reduction of nitroblue tetrazolium salt, which were shown to be suppressed by tea extracts. Extracts from both leaf and dust also inhibted the formation of hydroxyl radicalsin vitro in the enzymic system comprising hypoxanthine—Cu⁺²—sodium ascorbate and xanthine oxidase and in non enzymic system of deoxyribose—Cu⁺²—sodium ascorbate and H₂O₂ as well as the Cu⁺² induced lipid peroxidation in human low density lipoprotein. Feeding with black tea in normal rats for sixty days increased their antioxidant activity and their liver microsomes were shown to be protected against peroxidation of lipids as stimulated by metal ions with enzymic or non enzymic reactants. Furthermore feeding with tea extracts in normal as well as triton WR—1339 induced hyperlipidemic rats caused decrease in their plasma levels of total cholesterol, phospholipids and triglycerides. The antioxidant and lipid lowering activities of both extracts from CTC leaf and dust tea was comparable and may be due to the presence of natural products like catechin and others.     

Potent antiulcerogenic activity of ethanol extract of leaf ofPiper betle Linn by antioxidative mechanism

Pretreatment of an ethanolic extract of leaf ofPiper betle linn at a dose of 200mg/kg body weight, orally administered to rats for ten consecutive days, was found to possess a significant protective action against gastric lesions induced by indomethacin. The extract pretreatment resulted in significant increase in superoxide dismutase (SOD) and catalase (CAT) activity, increase in mucus, hexosamine and total thiol group content, but marked reduction in oxidatively damaged protein and peroxidised lipid levels as compared to untreated ulcerated control. The extract was also found to possess both superoxide and hydroxyl free radical scavenging action. The present observations establish the efficacy of the extract in prevention of experimentally induced peptic ulcer by indomethacin and antioxidant property appears to be predominantly responsible for such cytoprotective activity in the experimental model.     

An audit of total and free thyroxine measurements in screening for hypo and hyperthyroidism in patients using chemiluminescence immunoassay

An audit of 2509 patient specimens analyzed for both total thyroxine (TT4) and free thyroxine (FT4) by the ACS-180 automated chemiluminescence immunoassay analyzer revealed that there were 219 discrepancies (8.7% of the total). A discrepancy was defined as one analyte within its reference range and the other outside. The discrepant results were divided into 4 groups: group A: normal TT4, but decreased FT4, 101 patients (4.0%); group B: increased TT4, normal FT4, 78 patients (3.1%); group C: decreased TT4, normal FT4, 34 patients (1.4%); and group D: normal TT4, increased FT4, 6 patients (0.2%). TSH measurements were available, by a 3^rd generation chemiluminescent assay, in 142 of these patients, and were consistent with the FT4 result in 72 patients, with TT4 in 61 cases and with neither in 9 patients. The clinical diagnosis was investigated in a subgroup of 43 endocrine patients. Thirteen of the 20 endocrine patients in group A were diagnosed as hypothyroid, with a measured serum TSH, in 11 of them, of median 14.6, range 1.2 to 46.2 μlU/ml. Eleven of the 19 endocrine patients in group B were on thyroid replacement, with a measured serum TSH, in 7 of them of <0.01 μlU/ml. The audit of current laboratory practice led to a suggestion to replace the current thyroid function screening strategy of measuring both TT4 and FT4 by the combination of FT4 and TSH. The reasons for the discrepancies and the alternative strategies for screening of thyroid function are discussed.     

Effect of methyl mercury induced free radical stress on nucleic acids and protein: Implications on cognitive and motor functions

Mercury pollution and acute neurotoxicity of mercury is well known. The recent reports suggest the adverse effect of low dose mercury, though the available literature is still silent on its mechanism. This study was therefore undertaken to probe the effect of low dose methyl mercury induced heavy metal toxicity on free radical stress and its impact on behaviour of male albino rats. Male albino rats were exposed to 1 mg/kg body wt of methylmercury chloride for seven days, on day 8 they were tested for motor and memory functions. They were sacrificed later for biochemical estimations for rate of lipid peroxidation, nucleic acids, proteins in cerebrum, cerebellum and brain stem. There was an increase in the rate of lipid peroxidation showing methyl mercury induced free radical stress. The motor and memory functions demonstrated a clear decline, besides there was a lowering in the levels of nucleic acids and proteins as compared to controls. The results are important in view of recent reports that methyl mercury induced free radical stress results in early ageing and may serve as an initiating factor more specifically for neurodegenerative disorders like Alzeihemer's disease and dementias. The current findings support the notion that incorporating dietary antioxidants like curcumin, ascorbic acid and α-tocopherol in routine diet from early age may help combat the risk of developing such disorders in ensuing years.     

Killing off the Competition

In August 1929, James W. Upton, Editor of the republican newspaper, Honesty, discovered that that Seán Lemass and Gerald Boland, the Secretaries of the Fianna Fáil party, had issued a circular to their members that blackballed Honesty and promoted the sales of The Nation, a publication that Fianna Fáil's leader, Éamon de Valera, had recently brought under his control. The event that triggered this action was Upton's decision to publish an article critical of the Fianna Fáil leadership, something Upton did in the interest of freedom of speech. Upton, who was sympathetic to the Fianna Fáil cause, dubbed Lemass and Boland, ‘the Dublin Junta’ and accused them of launching an underhand attack to further their own careers and party ambitions. Fianna Fáil retaliated in the pages of The Nation, declaring that Honesty was no longer a republican journal and thereby destroying Honesty's readership. An exploration of these events reveals political duplicity and a fundamental misfit between the views of a republican idealist and hardheaded professional politicians. Upton believed that republicanism without journalistic freedom was no republicanism at all, whilst Lemass and Boland focused on building a disciplined party machine intent on suppressing dissent, within and without of its ranks.     

Solid Edge变量表在零件系列设计中的应用

文章分析了SolidEdge的变量表技术在甩油环系列设计中应用,并给出了详实图例。     

秀出行伍一枝笔为将风骨称其文——读贺茂之散文集《感激》

军旅作家贺茂之在《感激》中用生命的体验、燃烧的激情和灵动的彩笔记述了他三十七年军旅途中体味新颖、感情深刻、蕴含诗意和哲理的亲历、亲为和亲思。五十篇文章,皆系真人真事,真情真话,朴实自然、亲切感人。能“给人以德的浸润,才的引领、智的启迪、美的享受和力的激励”。     

关于正则变量的变换问题

本文利用了哈密顿原理推导出了正则变换条件的表达式，继而根据此条件推导出因母函数的不同而形式相异的四种变换方程，使解正则方程的过程得以简化。     

时滞对一类变系数SIR传染病模型的影响

考虑了一个时滞变系数SIR传染病模型,并获得了含有时滞的下界,且不同于其它文章的系统持久性条件,进一步给出疾病灭绝的充分条件.其目的是讨论变系数及时滞对系统持久与疾病根除的影响.     

数控机床加工非圆曲线的编程法研究

介绍用数控机床加工非圆曲线的一种编程方法。此方法将变量应用于程序编制中即变量编程法。同其它手工编程方法相比，该方法具有编程简单，加工精度高等优点。