A food-born carcinogen, 2-amino-3-methylimidazo [4,5-f] quinoline (IQ) induces cancer in the rat colon. The mechanism for colonic DNA adduct formation leading to cancer by IQ was studied using a colostomized F344 rat model. In this model, the transverse colon of the rat was colostomized, which produced a fecal stream-positive proximal colon and a negative distal colon were produced. When IQ (50...

The drug tamoxifen shows evidence of genotoxicity, and induces liver tumours in rats. Covalent DNA adducts have been detected in the liver of rats treated with tamoxifen, and these arise through metabolism at the alpha-position to give an ester which reacts with DNA. (E)-1-(4-iodophenyl)-2-phenyl-1-[4-(2-pyrrolidinoethoxy)phenyl]-but-1-en e (idoxifene) is an analogue of tamoxifen in which forma...

The levels of aflatoxin B(1)-DNA and aflatoxin B(1)-albumin adducts were investigated by accelerator mass spectrometry (AMS) in humans and rats following exposure to a known, dietary relevant amount of carbon-14 labeled aflatoxin B(1) ([(14)C]AFB(1)). The aims of the study were to: (a) investigate the dose-dependent formation of DNA and protein adducts at very low doses of AFB(1) (0.16 ng/kg-12...

Tamoxifen (TAM), a nonsteroidal antiestrogen used as a chemotherapeutic and chemopreventive agent for breast cancer, induces liver tumors in rodents and covalent DNA adduct formation in hepatic DNA. Here, we report the development and validation of highly sensitive and specific immunoassays for the determination of TAM-DNA adducts. Rabbits were immunized with calf thymus DNA, chemically modifie...

The somatostatins are peptides of 14 and 28 amino acids that are produced in a variety of endocrine and nonendocrine tissues. These peptides inhibit the secretion of many different pituitary, pancreatic, and gastrointestinal hormones. Previously, we have reported the isolation and nucleotide sequence of a cDNA derived from a rat medullary thyroid carcinoma that encoded preprosomatostatin , a 11...

Truncated mouse ribosomal DNA (rDNA) genes were stably incorporated into rat HTC-5 cells by DNA-mediated cell transfection techniques. The mouse rDNA genes were accurately transcribed in these rat cells indicating that there is no absolute species specificity of rDNA transcription between mouse and rat. No more than 170 nucleotides of the 5' nontranscribed spacer was required for the accurate i...

objective(s):one cause of cigarette smoking is oxidative stress that may alter the cellular antioxidant defense system, induce apoptosis in lung tissue, inflammation and damage in liver, lung, and kidney. it has been shown that chinese green tea (cgt) (lung chen tea) has higher antioxidant property than black tea. in this paper, we will explore the preventive effect of cgt on cigarette smoke-in...

this investigation aimed to examine the protective function of vitamin e on rat bone marrow mesenchymal stem cells (mscs) treated with cadmium chloride. rat bone marrow mscs were extracted using flashing-out and cultured in dmem containing 10% fbs and 100 u/ml pen/strep. at the end of the third passage, cells were divided into 4 groups including control, cadmium chloride, cadmium chloride + vit...

The nucleic acid sequences found in the Harvey strain of murine sarcoma virus have been analyzed by RNA.[(3)H]DNA and [(3)H]RNA.DNA hybridization techniques. The Harvey strain of murine sarcoma virus has been found to possess at least two sets of nucleic acid sequences. One set of sequences is contained in the Moloney strain of mouse type-C virus, and the other set is contained in DNA transcrip...

The p53 tumor suppressor gene is either nonfunctional or highly and frequently mutated in majority of cancers. In our study towards understanding cellular adaptations to stress using a rat histiocytic tumor model, we have identified mis-sense mutation in p53 that led to premature termination of translation at the carboxyl-terminus. Further, the cDNA isolated from heat stressed cells producing t...