广东海产鱼虾食品的挥发性亚硝胺测定

从海产鱼虾食品中可检测到不同水平的挥发性亚硝胺致癌物,其中以二甲基亚硝胺(NDMA)最为常见。香港Fong和Huang等曾分别报道,广州和香港市售海产食品中含NDMA和吡咯烷亚硝胺(N-Pyr.)。许多亚硝胺对各种实验动物能诱发出不同脏器的肿瘤。我国广东人群的鼻咽癌、肝癌和食管癌发病率很高,其中鼻咽癌占全省癌症发病总数的40.1％。广东沿海居民喜食咸鱼、干鱼等海产食品,这与当地高发肿瘤有无相关,值得注意。对食物中亚硝胺的定性定量分析,是探讨该地区鼻咽癌、肝癌和食管癌致病因素的一个重要环节。因此,我们对广东海产鱼、虾及其加工制品进行了挥发性亚硝胺分析,本文报道初步分析结果。

^3H—镰刀菌素C在大鼠体内的分布及与DNA的结合

<正> 镰刀菌素C(Fusarin C,FC)是Wiebe和Bjeldanes(1971)首先从玉米中分离得到的一种霉菌毒素,本实验室于1984年也从串珠镰刀菌的玉米培养基中分离出该毒素,FC对细菌和哺乳类动物细胞均有明显的致突变作用.为探讨FC的致癌作用及其与林县食管癌高发的关系,本实验初步研究~3H-镰刀菌素C(~3H-FC)在大鼠体内的分布、代谢及在体外与大鼠食管的DNA结合.

镰刀菌素C体外诱发大鼠食管上皮细胞转化的研究

本文报道用镰刀菌素C(FC),一种致突、致癌的真菌毒素,诱发大鼠食管上皮细胞体外转化作用,转化细胞可在选择培养基或半固体琼脂上生长,形成集落并具有非整倍体核型,以及C-myc和C-erb-B癌基因表达增强,更重要的是,经FC处理的细胞能在裸鼠体内形成鳞状细胞癌,实验结果表明,FC对大鼠食管上皮细胞具有恶性转化作用,本工作还提示癌基因表达异常可作为细胞转化的一种新指标。

In vitro TRANSFORMATION OF RAT ESOPHAGEAL EPITHELIAL CELLS BY FUSARIN C

Fusarin C (FC) is a mutagenic and carcinogenic mycotoxin which was isolated from Fu-sarium moniliforme culture extracts. The Fusarium moniliforme is one of most prevalent fungi found on corn in Linxian, a high risk area for esophageal cancer. This paper reports, for the first time, the malignant transformation of rat esophageal epithelial cells induced by FC. The transformed cells showed several characteristics of transformation. Colonies were formed after seeding these transformed cells either into selective medium free of epidermal growth factor (EGF) and serum, or on semi-solid agar; there was an increase in chromosome number; the expression of c-myc and v-erb-B oncogenes was enhanced in the cells; and squamous cell carcinomas arose after inoculating the cells into nude mice. The results demonstrated transforming effect of FC on rat esophageal epithelial cells, and indicate that the abnormal expression of some oncogenes could serve as a hew property of transformed cells.