Human bronchus is one target site for the carcinogenic action of tobacco smoke, which contains chemical carcinogens, including benzo(a)pyrene. Human bronchi were obtained from surgery or "immediate" autopsy and then cultured in a chemically defined medium. The cultured bronchi were exposed to either benzo(a)pyrene or its metabolites, and their levels of binding to DNA were measured. One of the ...

The potent carcinogen 2-hydroxybenzo(a)pyrene (2-OH-BP) competes for binding to the estrogen receptor in the cytosol of rat uterus and liver. The dissociation constant (K1) for this interaction is congruent to 2 X 10(-5) M. In contrast, 4-hydroxybenzo(a)pyrene does not bind to the estrogen receptor; 1-hydroxybenzo(a)pyrene, 5-hydroxybenzo(a)pyrene, 6-hydroxybenzo(a)pyrene, and 12-hydroxybenzo(a...

Uptake of benzo(a)pyrene by living cultured cells has been visualized in real time using digital fluorescence-imaging microscopy. Benzo(a)pyrene was noncovalently associated with lipoproteins, as a physiologic mode of presentation of the carcinogen to cells. When incubated with either human fibroblasts or murine P388D1 macrophages, benzo(a)pyrene uptake occurred in the absence of endocytosis, w...

Benzo(a)pyrene (BP) and several benzo-ring derivatives of BP were tested for carcinogenic activity in mice by topical application of each compound once every 2 weeks for 60 weeks. Chronic treatment of C57BL/6J mice with (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene (0.025 to 0.10 micronmole/application) indicated that the dihydrodiol was slightly more active as a complete carcinogen than ...

Polycyclic aromatic hydrocarbons (PAHs) are highly recalcitrant compounds due to their high hydrophobicity and tendency to partition in organic phase of soils. Pyrene is a high-molecular weight PAH, which has human health concerns. In the present study, a bacterial consortium, PBR, was developed from a long-term polluted site, viz., Amlakhadi, Ankleshwar, Gujarat, for effective degradation of p...

Abstract The aim of the study was to determine efficacy bioaugmentation in pyrene-contaminated soil based on microbial counts, colony development index (CD), ecophysiological diversity (EP), enzyme activity, and an assay residual pyrene levels soil. samples were contaminated with doses 100 1000 mg kg −1 DM Two bacterial consortia used study: P1 ( Bacillus frigoritolerans Z2B-19, simplex 2–134, ...

Investigations of fluorescence anisotropy and mean lifetime of pyrene and pyrene excimer in cellulose acetate films have shown that this environment can not be considered as a strictly rigid solution, being rather a medium consisting of empty spaces where small pyrene molecules have considerable freedom. It has been concluded that the mechanism of the excimer formation is the same as that in li...

Pyrene-intercalated layered compounds, [{Ru2(O2CCF3)4}2(TCNQR(x))]·2(pyrene) (TCNQR(x) = 7,7,8,8-tetracyano-p-quinodimethane derivatives; R(x) = H4 and F4), were synthesized. Pyrene prohibits intralayer electron transfer of [Ru2(II,II)] → TCNQR(x), even in the compound with R(x) = F4, from occurring.

The benzo[a]pyrene 4,5-, 7,8-, and 9,10-oxides and the six corresponding phenols (4-, 5-, 7-, 8-, 9-, and 10-hydroxybenzo[a]pyrene) have been tested for mutagenic and cytotoxic activity in bacteria and in a mammalian cell culture system. Benzo[a]pyrene 4,5-oxide (K-region) was highly mutagenic in two histidine-dependent strains (TA1537 and TA1538) of Salmonella typhimurium which detect frameshi...

This study investigated the biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) in liquid media and soil by bacteria (Stenotrophomonas maltophilia VUN 10,010 and bacterial consortium VUN 10,009) and a fungus (Penicillium janthinellum VUO 10, 201) that were isolated from separate creosote- and manufactured-gas plant-contaminated soils. The bacteria could use pyrene as...