Search results for "Carcinogenic"
showing 8 items of 48 documents
Metabolic activation of dibenzo[a,l]pyrene by human cytochrome P450 1A1 and P450 1B1 expressed in V79 Chinese hamster cells.
1999
Metabolic activation of the strongly carcinogenic polycyclic aromatic hydrocarbon (PAH) dibenzo[a,l]pyrene (DB[a,l]P) and its trans-8,9-dihydrodiol (trans-8,9-diol) catalyzed by human cytochromes P450 (P450) 1A1 and 1B1 was investigated. DNA binding of DB[a,l]P in mammalian cell lines has previously been shown to be preferentially mediated by fjord region DB[a,l]P-11,12-dihydrodiol 13,14-epoxides (DB[a,l]PDE). In order to elucidate different capabilities of both P450 enzymes for metabolic activation of DB[a, l]P V79 Chinese hamster cells, stably expressing human P450s 1A1 or 1B1 have been exposed to the parent PAH or its racemic trans-8, 9-diol. For this purpose, synthesis and spectroscopic…
Screening of some banned aromatic amines in textile products from Indian bandhani and gamthi fabric and in human sweat using micellar liquid chromato…
2021
Certain dyes in textile products, which are capable of reductively splitting into carcinogenic aromatic amines, are strictly controlled in many countries. A simple, rapid, sensitive and green chromatographic method has been developed and validated for the simultaneous determination of 4-aminophenol (4-AMP), p-phenylenediamine (p-PPD) and benzidine (BNZ), banned aromatic amines in dyeing clothes and human sweat. The separation was achieved using a micellar mobile phase of 0.1 M SDS, 4% 1- butanol (v/v) buffered to pH 7 with sodium dihydrogen phosphate, flowing under isocratic mode at 1 mL/min through a C18 column. Photodiode array detector was set at 210 nm. Using the above chromatographic c…
Challenging Dogma: Thresholds for Genotoxic Carcinogens? The Case of Vinyl Acetate
2002
Although many questions remain unanswered, the general principle of the sequence of events leading to cancer after exposure to genotoxic carcinogens has become increasingly clear. This helps to understand the parameters that influence the shape of the dose-effect curve for carcinogenesis, including metabolic activation and inactivation of carcinogens, DNA repair, cell cycle control, apoptosis, and control by the immune system. A linear dose-response relationship with no observable threshold seems to be a conservative but adequate description for the carcinogenic activity of many genotoxic carcinogens, such as aflatoxin B1, the tobacco-specific nitrosoketone NNK, and probably N,N-diethylnit…
Isolation, separation and quantification of metabolites of the carcinogenic polycyclic aromatic hydrocarbon dibenz(a,h)anthracene
1986
Mutagenicity of Closely Related Carcinogenic and Noncarcinogenic Compounds Using Various Metabolizing Systems and Target Cells
1980
A total of 49 heteropolycyclic compounds belonging to structurally homogenous series was investigated for bacterial mutagenicity in the Ames test. The same batches of compounds were tested for carcinogenicity by injection into subcutaneous tissue of mice? 22 test compounds were carcinogenic, some strongly, others weakly. With the exception of one weak carcinogen, all these compounds were mutagenic. However, 15 of 27 noncarcinogens (56%) were also mutagenic. Moreover, noncarcinogenic, weakly carcinogenic, and strongly carcinogenic mutagens showed very similar mutagenic potencies.
Carcinogenic aspect of xenobiotic molecules belonging to the peroxisome proliferator family.
1999
It is known that a short-term exposure of rat, mice or incubation of hepatic cells with fibrate molecules leads to increase in peroxisome number and cell hyperplasia. Further, long-term incubation of cells (at least a year) show transformed characteristics with foci and nodules. To explain the hepatocarcinogenic effect of peroxisome proliferators in rodents we studied the effect of peroxisome proliferators on rat liver oncogenes expression. Earlier, we reported an increase in liver and kidney mRNA level of c-myc and N-myc. Since several metabolic genes are activated by PPAR (peroxisome proliferators activated receptor) through a PPRE (peroxisome proliferator response element), we suggest th…
Steroid activities comparison of natural and food wrap compounds in human breast cancer cell lines
2004
Abstract In this study, we tested and compared the endocrine disruption activities of compounds in materials used to package foods (bisphenol A, bisphenol F, and bisphenol A diglycidylether BADGE) with natural molecules (genistein, apigenin, kaempferol, and tangeretin) in the human breast cancer cell lines MCF-7 (ER + ) and MDA-MB453 (AR + ; GR + ). Octylphenol was also chosen as a xenoestrogen reference. Two compounds had no estrogenic activity: BADGE and tangeretin. Genistein was the most active compound in the E-Screen assay with MCF-7, followed by octylphenol, bisphenol F, bisphenol A and apigenin, with kaempferol the least potent. All estrogenic compounds competed with 17β-estradiol fo…
Combined sub-optimal doses of Rosuvastatin and Bexarotene impairs angiotensin II-induced arterial mononuclear cell adhesion through inhibition of Nox…
2015
Aim: Mononuclear cell (MC) infiltration into the arterial subendothelium is a key event in atherogenesis. Rosuvastatin (Rosu) and bexarotene (Bex) exert anti-inflammatory activity, but serious dose-related adverse effects have emerged. The need for safer and effective strategies to prevent and treat atherosclerosis led us to test the effect of combined use of both drugs on angiotensin II (Ang-II)-induced arterial MC recruitment. Results: Vehicle, Rosu (10–30 nM), Bex (0.3–1 μM), or a combination of both were administered to human umbilical arterial endothelial cells (HUAECs) 20 h before stimulation with 1 μM Ang-II (4 h). Surprisingly, a combination of Rosu (10 nM)+Bex (0.3 μM), which did n…