斑马鱼胚胎和肿瘤细胞评价细胞毒药物活性比较研究*

目的:比较斑马鱼胚胎和肿瘤细胞作为药物筛选模型的优缺点.方法:采用MTT法检测顺铂、紫杉醇、阿霉素、5-氟尿嘧啶四种药物对HL-60和Hela细胞的增殖影响;同时,观察药物对斑马鱼胚胎发育的影响.结果:阿霉素、顺铂及紫杉醇作用于HL-60及Hela细胞的IC50均显著高于作用于斑马鱼胚胎的LD50;而5-FU作用于肿瘤细胞和斑马鱼胚胎的结果与其它药物相反;四种抗肿瘤药物对斑马鱼胚胎的生长发育均有致畸作用.结论:斑马鱼胚胎作为细胞毒类药物筛选模型,对于抗微管类药物较为敏感,但对于抗代谢药敏感性较肿瘤细胞差.     

Calcitriol derivatives with two different side chains at C-20 III. An epimeric pair of the gemini family with unprecedented antiproliferative effects on tumor cells and renin mRNA expression inhibition

The searches for drugs that exhibit antineoplastic activity and regulate blood pressure are among the most prevalent and compelling research activities today. Amazingly, there is ample precedence for the antiproliferative action of vitamin-D-related compounds and their role as endocrine suppressors of renin biosynthesis. We have recently synthesized a number of novel calcitriol analogs of the gemini family and originally selected for further studies an epimeric pair related to 19-nor-calcitriol whose 21-methyl group was replaced by a 5,5,5-trifluoro-4-hydroxy-4-(trifluoromethyl)-2-pentynyl group. While maintaining the acceptable calcemic responses, the IC50 concentrations of interferon-γ release were reduced and the antiproliferative activity and inhibition of renin mRNA expression enhanced. Replacing the geminal methyl groups on the calcitriol-related side chain of these gemini compounds with trideuteriomethyl moieties further boosted the potency in the colon cancer model in mice some 10-fold, reduced NMU-induced breast cancer carcinogenesis in rats and decreased the IC₅₀ values for renin mRNA inhibition into the pM range.     

两种新型醛糖还原酶抑制剂的合成

本文以５－氨基－１－萘磺酸为原料,用乙酰水杨酰氯酰化,得５－乙酰水杨酰氨基－１－萘磺酸,再经氯化后,与甘氨酸或丙氨酸酰化,合成了两种效果较好的新型醛糖还原酶抑制剂－５－乙酰水杨酰基－１－萘磺酰甘氨酸和－５－乙酰水杨酰氨基－１－萘磺酰丙氨酸。     

C 阿霉素一纤维蛋白胶缓释化疗系统对S ,80 荷瘤小鼠的抑瘤实验研究

目的：探讨阿霉素-纤维蛋白胶缓释化疗系统对S180荷瘤小鼠的抗肿瘤作用。方法：建立S180荷瘤小鼠模型,将30只模型小鼠分为四组：A组10只,阿霉素以2／剂量局部注入肿瘤内部。B组10只,瘤内注入阿霉素．纤维蛋白胶缓释系统0．2ml（含阿霉素2／）。C组10只。瘤块内注入纤维蛋白胶0．2ml。D组10只,空白对照组。给药后每3天测量记录一次肿瘤大小,观辑各组平均肿瘤体积缩小情况。结果：A、B、C、D四组的肿瘤缩小比率分别为50％、100％、20％、10％,肿瘤抑制率分别为36．85％、77．42％、6．00％、6．52％,与空白对照D组相比。A、B组对S180肉瘤抑制作用明显（P〈0．01）,而B组的抑瘤作用明显强于A组（P〈0．05）．C组与D组无明显差异（P〈0．05）。结论：阿霉素-纤维蛋白胶缓释化疗系统以及阿霉素均能够有效的抑制S180荷瘤小鼠肿瘤的生长。前者的抑瘤作用更为明显,可能是一种安全可靠的新化疗方式．     

alpha-Fluoro beta alanine in urine of workers occupationally exposed to 5 fluorouracil in a 5 fluorouracil producing factory

Because of possible harmful health effects increased attention is being paid to the occupational exposure to cytostatic drugs of workers in hospitals and industry. In this study a biomarker for exposure to 5-fluorouracil (5FU) based on GC-MSMS was applied to study the occupational exposure of four workers in a pharmaceutical factory producing 5FU. The four workers all excreted-fluoro--alanine (FBAL), a metabolite of 5FU, via the urine (range excretion rates: 0-88 9 g per 8h). This is in accordance with the presence of 5FU and/or its precursor ethoxyfluorouracil (EFU) in stationary and personal air wipe samples taken from the the workplace.     

The effects of boron containing peptides on L1210 lymphoid leukemia metabolism

Summary The purpose of this study was to establish the efficacy and mode of action of peptide boron derivatives as antineoplastic agents and to evaluate their safety in vivo. Boron-containing phenylalanine and tyrosine methyl esters were found to be potent cytotoxic agents in a number of murine and human cancer cell lines. DNA, RNA and protein syntheses were inhibited by selected agents, e.g. [(trimethylamine boryl)carbonyl]-phenylalanine-acetyl ester (9) andN-acetyl-p-boron-phenyl-alanyl-phenlalanine-methyl ester (10), in L₁₂₁₀ lymphoid leukemia cells. IMP dehydrogenase, OMP decarboxylase, m-RNA, t-RNA, r-RNA polymerase and ribonucleoside reductase activities were inhibited. d(CTP) levels were reduced. DNA strand scission occurred after 24 hr incubation. Acute toxicity studies in mice demonstrated that the key derivative was safe at therapeutic levels with no effects on histology of major organs, hematopoietic parameters and clinical values.     

A systematic review of instrumental variable analyses using geographic region as an instrument

BackgroundInstrumental variables analysis is a methodology to mitigate the effects of measured and unmeasured confounding in observational studies of treatment effects. Geographic area is increasingly used as an instrument.MethodsWe conducted a literature review to determine the properties of geographic area in studies of cancer treatments. We identified cancer studies performed in the United States which incorporated instrumental variable analysis with area-wide treatment rate within a geographic region as the instrument. We assessed the degree of treatment variability between geographic regions, assessed balance of measured confounders afforded by geographic area and compared the results of instrumental variable analysis to those of multivariable methods.ResultsGeographic region as an instrument was relatively common, with 22 eligible studies identified, many of which were published in high-impact journals. Treatment rates did not vary greatly by geographic region. Covariates were not balanced by the instrument in the majority of studies. Eight out of eleven studies found statistically significant effects of treatment on multivariable analysis but not for instrumental variables, with the central estimates of the instrumental variables analysis generally being closer to the null.ConclusionsWe recommend caution and an investigation of IV assumptions when considering the use of geographic region as an instrument in observational studies of cancer treatments. The value of geographic region as an instrument should be critically evaluated in other areas of medicine.