MULTIDRUG RESISTANT TUBERCULOSIS – BIOMECHANISM,EPIDEMIOLOGY AND MANAGEMENT STRATEGIES

Muitidrug resistant tuberculosis has shown an alarming increase and this assumes added importance in view of the increasing number of HIV infected patients. This article reviews the biomechanism of resistance and discusses the present stategies that are available and recommended to tackle the rising incidence of tuberculosis due to resistant mycobacteria.KEYWORDS: Antitubereular drugs, Drug resistance, Mycobacterium tuberculosis     

HPLC柱切换法血浆直接进样测定糖肾平

采用HPLC柱切换技术,以Merck Lichroprep RP2(25～40μm)为预处理柱填料,以水为预处理流动相,以0.2mol/L乙酸-乙酸铵为净化清洗液,血浆直接进样,在线富集净化样品。血浆样品以0.2ml/min慢速转移通过预处理柱,净化回收率达80%。以ShimpackCLC-ODS为分析柱(15cm×6mm,ID),甲醇-异丙醇-0.2mol/L 乙酸铵(61:5:34)为分析流动相,310nm波长检测,外标法定量测定人体血浆中糖肾平的浓度。血浆样品仅需稀释后即可进样,净化富集样品操作简便,预处理柱可长期反复进样使用。血浆中最低检测浓度为30ng/ml,日内变异系数为2.0%～5.4%,日间变异系数为2.4%～2.7%,在浓度为60～2020ng/ml血浆范围内呈线性关系。     

Carcinogenic polycyclic aromatic hydrocarbons increase intracellular Ca2+ and cell proliferation in primary human mammary epithelial cells

Previous studies have shown that polycyclic aromatic hydrocarbons (PAHs) mobilize intracellular Ca2+ in human T cells by inositol trisphosphate-dependent mechanisms resulting from activation of phospholipase C-gamma by SRC-related protein tyrosine kinases, thereby mimicking antigen-receptor activation. Ca2+ appears to play an important second messenger role in growth factor control of cell proliferation in human mammary epithelial cells (HMEC), such as the epidermal growth factor receptor pathway. The purpose of the present studies was to determine if PAHs are able to increase intracellular Ca2+ in primary cultures of HMEC and increase cell proliferation. Two carcinogenic and two non-carcinogenic PAHs were tested for their ability to increase intracellular Ca2+ in HMEC. The carcinogenic PAHs dimethylbenz[a]anthracene (DMBA) and benzo[a] pyrene (BaP) were able to cause Ca2+ elevation in HMEC at early time points (2 h) and caused sustained alterations in Ca2+ homeostasis (18 h). DMBA showed maximal effects at early time points (2 h), while BaP showed maximal effects on sustained Ca2+ (18 h). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a potent dioxin and tumor promoter, produced maximal Ca2+ elevation at 2 h, with a return to near baseline levels by 6 h. The non-carcinogenic PAHs benzo[e]pyrene and anthracene did not significantly alter intracellular Ca2+ at any time point. alpha-Naphthoflavone significantly reduced the Ca2+ response induced by BaP treatment, but not by DMBA or TCDD, suggesting that P450 1A or 1B metabolism of BaP may be important in the sustained Ca2+ elevating response. In evaluating the effects of BaP on HMEC proliferation, BaP was found to increase the number of cells recovered after 4 days in culture in the absence or presence of various concentrations of epidermal growth factor. These studies provide initial evidence that Ca2+ signaling may be associated with mitogenesis in HMEC, which may play a role in tumor promotion and progression produced by PAHs.      

交流示波极谱滴定法测定盐酸环丙沙星及其制剂的含量

目的：采用交流示波极谱滴定法测定了盐酸环丙沙星及其制剂的含量。方法：在ｐＨ５．０－５．５的醋酸－醋酸钠缓冲液溶液中，环丙沙星与四苯硼钠定量反应形成１：１沉淀。过量的四苯硼钠用醋酸亚铊标准溶液回滴至示波极谱图上四苯硼钠切口消失。结果：该法平均回收率为９９．１８％，ＲＳＤ为０．４９％。结论：本法简便，快速，结果准确，可靠。     

睾丸酮、雌二醇和棉酚合并用药的雄性抗生育作用及其安全性的研究

睾丸酮、雌二醇和棉酚合并用药的雄性抗生育作用及其安全性的研究叶惟三，但凌，郭燕，钱晓菁，应骏，薛社普（中国医学科学院，中国协和医科大学基础医学研究所，北京１００００５）减轻有抗男性生育活性棉酚的副作用是发展棉酚成为男性避孕药急待解决的问题［１，２］。...     

抗癌及癌化学预防药物的研究:3-α-酮醛香豆素衍生物的合成及其抗致突活性与结构间的关系

α-酮醛及其衍生物在抗病毒、抗肿瘤方面有一定活性。我们合成了18个新的3-α-酮醛香豆素衍生物,研究该类化合物的质谱裂解方式与氢核磁共振谱的特征峰。体外药理筛选发现其中部分化合物有不同程度的抗致突活性,对其构效关系进行了分析,并提出了这类化合物产生抗致突活性的可能亚结构。     

抗癌及癌化学预防药物的研究：3α酮醛香豆素衍生物的合成及其抗致突活性与结构间的关系

α酮醛及其衍生物在抗病毒、抗肿瘤方面有一定活性。我们合成了１８个新的３α酮醛香豆素衍生物，研究该类化合物的质谱裂解方式与氢核磁共振谱的特征峰。体外药理筛选发现其中部分化合物有不同程度的抗致突活性，对其构效关系进行了分析，并提出了这类化合物产生抗致突活性的可能亚结构     

合欢皮中三萜皂甙元的研究

合欢皮中三萜皂甙元的研究陈四平张如意（北京医科大学植化教研室，北京１０００８３）中药合欢皮（Ａｌｂｉｚｚｉａｅｃｏｒｔｅｘ）为合欢（ＡｌｂｉｚｚｉａｅｊｕｌｉｂｒｉｓｉｎＤｕｒａｚｚ）树皮。具解郁安神，活血消肿功能。用于心神不安，忧郁失眠，肺痈疮肿...