ISSN:0192-2521    

DOI:10.1002/em.2860060202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractSamples of airborne particles have been collected in the same room when the room was heated by electricity and when heating was done by woodburning. These samples were compared with respect to mutagenic activity and concentration of polycyclic aromatic hydrocarbons (PAH). The effects of the various heating conditions were examined in the presence and absence of tobacco smoking.Whereas wood heating in an “airtight” stove was found to cause only minor changes in the concentration of PAH and no measurable increase of mutagenic activity of the indoor air, both these parameters increased considerably when wood was burned in an open fireplace, yielding PAH concentrations comparable to those of ambient urban air. Relatively high concentrations of moderately polar polycyclic aromatic hydrocarbon derivatives were also found in the indoor air when wood was burned in an open fireplace. Woodburning in the closed stove did, however, result in increased concentrations of mutagenic compounds and PAH on particles sampled in the vicinity of the house.The effects of wood burning in an open fireplace on the mutagenic activity of indoor air could still be considered moderate when compared to those resulting from tobacco smoking in the room. The extracts of particles collected when moderate smoking occurred were several times more mutagenic than samples from urban air collected close to streets with heavy traffic when measured in theSalmonellaassay with strain TA98 with metabolic activat

ISSN:0192-2521    

DOI:10.1002/em.2860060203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractStack‐collected coal fly ash from western low‐sulfur coal was extracted with 60:40 benzene/methanol. This extract was fractionated by preparative‐scale high performance liquid chromatography (HPLC) and the mutagenic activity of 14 fractions was evaluated by microbial assay withSalmonellatyphimurium TA1538. A widespread distribution of direct‐acting mutagens, which probably includes both mono‐ and dinitroaromatics, was detected.HPLC methods were also used to isolate 1‐nitropyrene from the total benzene/methanol extract. The identification of 1‐nitropyrene was based on gas chromatographic and HPLC retention measurements and mass spectral data. The concentration of 1‐nitropyrene in the ash extract was determined by quantitative HPLC analyses. Mutagenicity assays of the total extract and an authentic 1‐nitropyrene standard withSalmonellastrains TA1538, TA100, and TA98 indicated that the 1‐nitropyrene accounts for approximately 0.03‐0.16% of the total mutagenic ac

ISSN:0192-2521    

DOI:10.1002/em.2860060204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThe AmesSalmonella/microsome test was used to compare the mutagenic response ofSalmonella typhimuriumTA100, TA98, TA1538, and TA1535 to 12 benzidine derivatives, ie, benzidine, 3,3′‐dimethoxybenzidine, 3,3′‐dimethylbenzidine, 3,3′‐dichlorobenzidine, and the correspondingN‐ and W,W‐diacetylated derivatives. With a few exceptions, the mutagenic response to this series of compounds varied in the order TA98>TA1538>TA100>TA1535 = 0, and theN‐monoacetylated derivatives were more mutagenic than either the parent diamines or theN,N′‐diacetyl derivatives. The relative mutagenicities of the parent amines for TA98 were 3,3′‐dichlorobenzidine>>3,3′‐dimethoxybenzidine>ben

ISSN:0192-2521    

DOI:10.1002/em.2860060205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractA novel test system for the detection of mutagenic and recombinogenic activity of chemicals is described in detail.Drosophila melanogasterlarvae trans‐heterozygous for the mutations multiple wing hairs (mwh) and flare (fir) are exposed to the test compounds for various periods of time ranging from 96 hr to 1 hr. Induced mutations are detected as single mosaic spots on the wing blade of surviving adults that show either the multiple wing hairs or flare phenotype. Induced recombination leads to mwh and fir twin spots and also to a certain extent, to mwh single spots. Recording of the frequency and the size of the different spots allows for a quantitative determination of the mutagenic and recombinogenic effects. This and earlier studies with a small set of well‐known mutagens indicate that the test detects monofunctional and polyfunctional alkylating agents (ethyl methanesulfonate, diepoxybutane, mitomycin C, Trenimon), mutagens forming large adducts (aflatoxin B1), DNA breaking agents (bleomycin), intercalating agents (5‐aminoacridine, ICR‐170), spindle poisons (vinblastine), and antimetabolites (methotrexate). In addition, the test detects mutagens unstable in aqueous solution β‐propiolactone), gaseous mutagens (1,2‐dibromoethane), as well as promutagens needing various pathways of metabolic activation (aflatoxin B1, diethylnitrosamine, dimethylnitrosamine, mitomycin C, and procarbazine). The rapidity and ease of performance as well as the low costs of the test necessitate a high priority for validation of this promisingDrosophilasho

ISSN:0192-2521    

DOI:10.1002/em.2860060206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractAs part of the validation phase of theDrosophila melanogastersegment of the National Toxicology Program, a comparison has been made of positive and negative controls for sex‐linked recessive lethal mutations and reciprocal translocations from three laboratories. This comparison involves approximately 700,000 spontaneous recessive lethal mutation tests, 70,000 spontaneous translocation tests, and screens for genetic damage induced by N‐nitrosodimethylamine and β‐propiolactone. Spontaneous frequencies for lethal mutations and translocations were homogeneous in the laboratories regardless of solvent or broods sampled. Inhomogeneity was observed in induced frequencies among laboratories, but the variation was no greater than that found within a labo

ISSN:0192-2521    

DOI:10.1002/em.2860060207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

Abstract3‐Aminobenzamide (3AB) is a potent inhibitor of poly(ADP‐ribose) synthesis and has been reported to inhibit DNA repair. Inhibition of poly(ADP‐ribose) synthesis by 3AB results in a potentiation of the cytotoxic effects of alkylating agents and synergistically increases the frequency of sister chromatid exchanges (SCEs) induced in Chinese hamster ovary cells by methyl methanesulfonate (MMS). Experiments were carried out to determine if this synergism was related to an inhibition of the repair or the removal of SCE‐forming lesions by 3AB. Cells were treated with MMS or ethyl nitrosourea (ENU) and either held in a nonproliferative state or maintained in exponential growth for up to 48 hr before SCE frequencies were measured. During this time, the SCE frequency decreased greatly. 3AB did not affect this decrease in either cycling or noncycling cells. Furthermore, 3AB appears to exert its effect only in cycling cells when bromodeoxyuridine is present. Therefore, the synergism between 3AB and alkylating agents in the induction of SCEs is unrelated to effects of 3AB on the repair or removal of SCE‐formin

ISSN:0192-2521    

DOI:10.1002/em.2860060208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractDespite the fact that the nonsteroidal estrogen diethylstilbestrol (DES) exerts its toxic effects primarily on the reproductive system, little is known about the possible interference of this compound with germ cell DNA. The measurement of unscheduled DNA synthesis (UDS) in spermatocytes and early spermatids of mice germ‐cells is a valid indicator for the DNA‐damaging potential of a compound. UDS occurrence was thus determined after IP administration of 10, 30, 60 or 180 mg/kg DES to male mice. Tritiated thymidine ([3H]dThd) was then injected into the testes, the spermatozoa were serially collected, the sperm heads isolated, and UDS determined by the amount of [3H]dThd incorporation.[3H]dThd measurements in germ cells of mice which were treated with 10 mg/kg DES were comparable to those of the controls. Higher incorporation of [3H]dThd, indicating UDS, was measured in sperm cells which had been spermatocytes at the time of treatment with 30 and 60 mg/kg DES; this increase was statistically significant at 60 mg/kg. Administration of 180 mg/kg DES caused [3H]dThd incorporation which was comparable to that of the controls, suggesting that DES interfered with repair mechanisms or delayed spermatogenic cycles at high dose levels. General toxicity was manifested in a dose‐dependent decrease of the sperm cell numbers in the spermatogenic stages investigated.This study provides evidence that DES, or its metabolite(s), reached the germ cells of adult mice in sufficient amounts to produce DNA damage. The levels of radioactivity measured were comparable to those measured after cyclophosphamide treatment, but [3H]dThd incorporation was about 10 times less than in methylmethane sulfonate‐treated

ISSN:0192-2521    

DOI:10.1002/em.2860060209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractTo assess the effects of γ‐radiation on stem‐cell survival and incidence of reciprocal translocations, boar testes were irradiated with 100, 200, or 400 rad. Stem‐cell survival was markedly affected by 100 rad (51 % of control) and reduced to 34% of control by 400 rad. Production of differentiating spermatogonia was all but completely interrupted by 200 rad and spermatogonial renewal was incomplete at 12 weeks. From the state of the seminiferous epithelium at 12 weeks, estimates of the percentage of permanent impairment of sperm‐producing capacity ranged from 20 ± 6 (100 rad) to 67 ± 10 (400 rad). Incidence of translocations peaked at 200 rad and the number occurring at 100 and 400 rad was similar. Kinetics of porcine spermatogonial renewal differs considerably from those of the rodent and, relative to the rodent, this may account for the boar's higher sensitivity to stem‐cell killing and lower sensitivity to tr

ISSN:0192-2521    

DOI:10.1002/em.2860060210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

ISSN:0192-2521    

DOI:10.1002/em.2860060211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY