bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of mouse liver stored vitamin A on the induction of mutations (Ames tests) and SCE of bone marrow cells by aflatoxin B1, benzo(a)pyrene, or cyclophosphamide
Authors: Qin S. , Huang C. C. 
Published: February 2007

AbstractMale mice (C57BL/6J) at 2 weeks of age were divided into two groups and maintained on a vitamin A‐deficient or vitamin A‐ (retinyl acetate) supplemented diet. After 8 weeks, the average liver vitamin A concentration of mice fed on vitamin A‐deficient or ‐supplemented diet was 36 ± 7 μg/g vs 287 ± 22 m̈g/g, respectively. Uninduced liver S9 fractions were prepared from both groups of mice and used to activate (with cofactors) the precarcinogens aflatoxin B1 (AFB), cyclophosphamide (CPP), dimethylbenz(a)anthracene (DMBA), and benzo(a)pyrene (BP) in the Salmonella mutagenicity assay. S9 fraction prepared from both groups of mice failed to activate CPP to metabolites mutagenic in tester strains TA100 and TA1535 or to activate DMBA to metabolites mutagenic in TA100, but effectively activated AFB and BP to metabolites mutagenic in TA98. Comparison of activation activities of S9 prepared from liver of mice fed a high or low level of vitamin A was made with T98 treated with AFB or BP using three doses of S9 (50, 100, and 200 m̈l/plate). S9 fractions from mice with a high liver vitamin A level were consistently less potent than S9 fractions from mice with a low liver vitamin A level in activating AFB to its mutagenic metabolities. This effect was not observed in BP‐treated plates. Administration of AFB to groups of mice with a high liver vitamin A level induced significantly less SCE in bone marrow cells than did administration of AFB to mice with a low liver vitamin A level. This differential sensitivity was not observed when the two groups of mice were treated with either BP or CPP. The possible relationship between vitamin A levels in vivo and mutagenesis or carcinogenesis are discussed briefly.
Genotoxic effects in cultured mammalian cells produced by low pH treatment conditions and increased ion concentrations
Authors: Brusick David 
Published: February 2007

AbstractA workshop describing the mutagenic effects of low pH and high osmotic levels on cultured mammalian cells was held at the 16th Annual Meeting of the Environmental Mutagen Society in Las Vegas, Nevada, 1985. Data presented in this summary report were generously provided by the five invited speakers.
Genotoxicity studies of methyl isocyanate in salmonella, drosophila, and cultured chinese hamster ovary cells
Authors: Mason J. M. , Zeiger E. , Haworth S. , Ivett J. , Valencia R. 
Published: February 2007

AbstractThe genotoxic effects of methyl isocyanate (MIC) were investigated using four short‐term tests: the Salmonella reversion assay (Ames test), the Drosophila sex‐linked recessive lethal assay, and the sister chromatid exchange (SCE) and chromosomal aberration assays in cultured Chinese hamster ovary (CHO) cells. No evidence was found for the induction of mutations in either Salmonella or Drosophila. MIC did, however, induce SCEs and chromosomal aberrations in CHO cells both in the presence and absence of Aroclor‐induced rat liver S‐9.
Methyl isocyanate: An evaluation of in vivo cytogenetic activity
Authors: Tice Raymond R. , Luke Carol A. , Shelby Michael D. 
Published: February 2007

AbstractThe ability of inhaled methyl isocyanate (MIC) to induce genotoxic and cytotoxic damage in vivo was evaluated by assessing the induction of chromosomal aberrations (CAs) and sister chromatid exchanges (SCEs) in bone marrow metaphase cells, the induction of micronuclei in polychromatic erythrocytes (MN‐PCEs), and the inhibition of bone marrow cellular proliferation and erythropoiesis. B6C3F1 mice were exposed to MIC by two exposure regiments: (a) in two experiments, male mice only were exposed to 3, 10, and 30 ppm for 2 hr(b) in four experiments, male and female mice were exposed to 1 and 3 ppm (in one experiment, to 6 ppm, also, 6 hr per day for 4 consecutive days. The various cytogenetic endpoints were analyzed in bone marrow and peripheral blood (4‐day exposure regimen only) samples taken from bromodeoxyuridine tablet‐implanted animals killed 11 to 22 hr after cessation of the exposure to MIC. Exposure to MIC for 2 hr induced a significant delay in cellular proliferation but did not induce a significant increase in CAs, SCEs (evaluated at 3 and 10 ppm, only) or in bone marrow MN‐PCEs. Also, this exposure regimen did not inhibit the rate of erythropoiesis. Following exposure to MIC for 4 days, a weak but significant increase in CAs and SCEs was observed in male (in one experiment) and in female (in two experiments) mice. The induction was especially apparent in the single experiment in which mice were exposed to 6 ppm MIC. At this concentration, a significant increase in MN‐PCEs in peripheral blood was observed in male but not female mice. Delay in bone marrow cell proliferation was observed in male mice beginning at 3 ppm and in female mice at 6 ppm. The 4‐day exposure regimen resulted also in a depressed rate of erythropoiesis, with male mice appearing to exhibit greater depression than female mice. The results demonstrate that exposure to MIC by inhalation results in bone marrow damage, indicating the systemic genotoxic/cytotoxic activity of MIC and/or reactive metabolites.
Induction of sperm abnormalities in mice by quercetin
Authors: Rastogi P. B. , Levin R. E. 
Published: February 2007

AbstractSperm abnormalities in mice induced by IP injection of quercetin at total cumulative doses of 16, 32, 80, and 160 mg/kg b. wt. administered fractionally on 5 successive days were quantitated by assessing the percent of sperm with abnormal heads or tails. Five weeks after the final injection a maximum of 14.8% abnormal sperm were observed with a total quercetin dose of 80 mg/kg b. wt. compared to the spontaneous control of 0.98%. Concomittantly, a 32.1% reduction in testicular weight occurred compared to control mice which was coincident with a reduction in sperm count of 28 %.
Re‐evaluation of 1,2‐dimethylhydrazine in the mouse bone marrow micronucleus assay: Observation of a positive response
Authors: Ashby J. , Mirkova E. 
Published: February 2007

Abstract1,2‐Dimethylhydrazine showed dose‐related clastogenic activity in the mouse bone marrow micronucleus assay following intubation of an aqueous solution of the dihydrocholoride salt (10 and 50 mg/kg, 24 h sampling). These data counter earlier reports of the inactivity of this material in a rat and a mouse micronucleus assay, following its intraperitoneal injection. In the present study, 2,000 polychromatic erythrocytes were assessed per animal. However, had only 300 cells been assessed for micronucleated polychromatic erythrocytes, it is shown that a negative result could have been recorded. This may explain the earlier and negative results.
Mutagenicity and clastogenicity of acrylamide in L5178Y mouse lymphoma cells
Authors: Moore Martha M. , Amtower Amanda , Doerr Carolyn , Brock Karen H. , Dearfield Kerry L. 
Published: February 2007

AbstractAcrylamide was tested without exogenous activation in L5178Y/TK+/− −3.7.2C cells for mutation at the thymidine kinase locus and for clastogenicity. Acrylamide gave a positive induced mutagenic response (approximately 70 mutants/106 survivors) when tested at 600–650 μg/ml. The highest dose tested (850 μg/ml) resulted in an induced mutant frequency of approximately 380 mutants/106 survivors (survival = 13%). Acrylamide induced almost exclusively small‐colony mutants, indicating that it might be acting by a clastogenic mechanism. As predicted, acrylamide was clastogenic, inducing both chromatid and chromosome breaks and rearrangements. A clearly positive clastogenic response was observed at both the 750 μg/ml and 850 μg/ml doses, which showed 16 and 64 aberrations per 100 cells, respectively (background = 3 aberrations per 100 cells). These studies indicate that the L5178Y/TK+/− mouse lymphoma assay can detect some chromosomal mutagens (clastogens) that show little activity in other single gene mutation assays, the CHO/HPRT and Salmonella.
Mutagenicity testing of 5‐(4‐nitrophenyl)‐2,4‐pentadien‐1‐al (Spy Dust) and its metabolites in vitro and in vivo
Authors: Zeiger Errol , Shelby Michael D. , Ivett James , McFee Alfred F. 
Published: February 2007

Abstract5‐(4‐Nitrophenyl)‐2,4‐pentadien‐1‐al (NPPD; spy dust) was tested for mutagenicity in Salmonella and for its ability to induce chromosome aberrations and sister chromatid exchanges (SCE) in cultured Chinese hamster ovary (CHO) cells and mouse bone marrow. Two metabolites of NPPD produced by the rat, 4‐nitrobenzoic acid (NBA) and 4‐nitrohippuric acid (NHA), were also tested in Salmonella and CHO cells. NPPD was mutagenic in Salmonella, and induced low‐level increases in chromosome aberrations and SCE in bone marrow. It did not induce aberrations in CHO cells. NBA was positive in Salmonella and CHO cells, while NHA was negative. The mutagenicity of NPPD in Salmonella was partially, but not completely, eliminated in a strain lacking one of the bacterial nitroreductases.
Evaluation of pluronic® polyol F127 as a vehicle for petroleum hydrocarbons in the Salmonella/microsomal assay
Authors: Marino Dale J. 
Published: February 2007

AbstractComplex hydrocarbon mixtures have proven difficult to evaluate in in vitro mutagenicity assays owing to their insolubility in aqueous environments. Pluronic® Polyol F127 (BASF Wyandotte, Parsippany, NJ), prepared as a 50% (w/w) solution in absolute ethanol, proved effective in emulsifying various petroleum hydrocarbon fractions. Its effectiveness in the Salmonella/microsomal assay was evaluated using model solutions each comprising a polycyclic aromatic hydrocarbon (PAH) dissolved in mineral oil. The PAHs used were benzo(a)pyrene, 3‐methylcholanthrene, and 7,12‐dimethylbenzanthracene. Model solutions were evaluated neat and as emulsions with the Pluronic® F127 solution or Tween 80. Similar levels of each PAH were prepared in dimethyl sulfoxide (DMSO) for comparison. Cytotoxicity and mutagenesis were evaluated in the preincubation technique using strain TA97. Little or no cytotoxicity or mutagenesis was evident for model solutions tested neat. However, emulsification of these PAH‐laden mixtures with the Pluronic® F127 solution yielded cytotoxic and mutagenic responses similar to, or greater than, those observed for PAHs delivered in DMSO. Model mixtures emulsified with Tween 80 were less active. Study results demonstrate that Pluronic® F127, prepared as a 50% (w/w) solution in absolute ethanol, is an effective vehicle for evaluating the mutagenic potential of complex hydrocarbon mixtures containing PAHs in the Salmonella/microsomal assay. Since PAHs are a class of insoluble hydrocarbons, the results also suggest the potential usefulness of the Pluronic® F127 solution to detect the mutagenicity of other insoluble hydrocarbons and hydrocarbon mixtures.
Plasmid pKM101 muc‐− and muc‐+ mediated anthracycline mutagenicity and cytotoxicity in Salmonella typhimurium
Authors: Thomas Harvey F. , Cole Janice A. , Freeman Brantley 
Published: February 2007

AbstractMuc (mutagenesis: UV:chemical) genes of plasmid pKM101, along with the chromosomal gene recA are known to be important constituents for full expression of inducible error‐prone DNA repair in Salmonella typhimurium. This study investigates the affects of muc+ pKM101 and three of its derivatives bearing muc− point mutations (pGW1, pGW16, and pGW21) on spontaneous as well as anthracycline‐induced back mutation to histidine independence. Different base‐substitution and frameshift his− tester strains of S typhimurium were treated with the anthracyclines daunomycin, Adriamycin, carminomycin, and 4‐demethoxy‐doxorubicin. In many cases the muc− plasmids did mediate dose‐dependent anthracyline mutagenicity as measured by His+ reversion. In many of the his− strains, the presence of muc+ pKM101 or muc− plasmids also resulted in a concomitant elevation of spontaneous reversion patterns over those seen with the plasmid‐free parent strains. As a result, the sensitivity of most strains to anthracycline mutagenicity (based on His+ revertants/spontaneous background/μg anthracycline) was not enhanced by muc+ pKM101 or its muc− mutant derivatives. In contrast, the low incidence of spontaneous His+ reversion in strains of the hisD3052 series, along with the inherently greater sensitivities of these strains to anthracycline‐induced reversion, demonstrate most dramatically the mutagenesis‐enhancing effects of muc+ pKM101 and muc− plasmids. In these and other cases in which muc− plasmid effects on enhancement of strain sensitivity to mutagenesis or cytotoxicity are observed, the overall spectrum of enhancement is the following, in decreasing order: pKM101 > pGW16 > pGW1 > no plasmid = pGW21. Possible correlations are drawn between muc− plasmid effects on anthracycline‐induced mutagenesis and cytotoxicity.
Genotoxicity of three‐carbon compounds evaluated in the SCE test in vitro
Authors: von der Hude Wilhelm , Scheutwinkel Michael , Gramlich Ulrike , Fibler Brigitte , Basler Armin 
Published: February 2007

AbstractThree‐carbon chemicals (chlorinated and nonchlorinated, saturated and unsaturated, hydroxy‐ and oxo‐hydrocarbons) were assayed for genotoxicity. The sister chromatid exchange test in vitro served as the test system. Without S9 mix, the nonchlorinated solvents 1‐propanol, 2‐propanol, and 2‐propanone (acetone) did not increase the SCE frequencies. All chlorinated 3‐C hydrocarbons, except 1,2,3‐trichloropropane, proved to be potent SCE inducers in V79 cells without S9 mix.In the presence of S9 mix, the results obtained with the nonchlorinated solvents were also negative, whereas 1,2,3‐trichloropropane was transformed to SCE‐inducing metabolites. The addition of S9 mix resulted in an increased SCE rate for 2,3‐dichloropropanol, whereas genotoxicity of 2,3‐dichloropropene, 1,2‐di‐chloropropane, 1,3‐dichloropropene, and 1,3‐dichloropropanone was reduced. 1,3‐dichloropropanol, 1,3‐dichloropropene, and epichlorohydrin were substantially inactivated by S9 mix in the V79/SCE test.It can be concluded that the reactivity of the saturated dichloro compounds in the SCE test depends on the degree of oxidation. There is no general difference between the reactivity of α,β‐dichloro and α,ω‐dichloro compounds.
Evaluation of aflatoxin B1 mutagenesis: Addition of glutathione and glutathione‐S‐transferase to the salmonella mutagenicity assay
Authors: Jorgensen Karen V. , Clayton J. Wesley , Price Ralph L. 
Published: February 2007

AbstractThe effects of glutathione (GSH) and the combination of GSH and glutathione‐S‐transferase (GST) on aflatoxin B1 (AFB1) mutagenesis in the Salmonella mutagenicity assay using Salmonella typhimurium strains TA98 and TA100 were tested. Ten concentrations of AFB1 (0‐1.0 μg/plate) were added to a liver microsomal homogenate (S9 mix) or to S9 mix containing GSH or S9 mix containing the combination of GSH+GST. One‐third of the samples were plated directly. Two‐thirds were incubated for 30 min at 37°C prior to plating, and of those, half included bacteria. All samples were plated according to Ames et al [1975]. The results show that the addition of GSH and GSH+GST affected AFB1 mutagenesis by forming the AFB1‐GSH conjugate and decreasing the availability of AFB1‐8,9‐epoxide. The effect of GST on GSH activity varied with the strain because of the different amounts of S9 mix used. The formation of the AFB1‐GSH conjugate was verified by using reverse‐phase high‐performance liquid chromatography for quantitation of AFB1 and detection of AFB1‐GSH.
Perspective in the environmental health sciences: A meeting report
Authors: Goldstein Linda L. , Rosenkranz Herbert S. 
Published: February 2007

AbstractOn June 26 and 27, 1986, the Charles A. Dana Foundation sponsored the Conference on the Environmental Health Sciences at Case Western Reserve University School of Medicine in Cleveland, Ohio. Hosted by Dr. Herbert S. Rosenkranz, Chairman of the Department of Environmental Health Sciences at Case Western Reserve University, the conference brought together, for the first time, sixteen academic leaders in the field of environmental health from around the country. In five sessions held over two days, the mission of the participants was to discuss the setting of policies and curricular standards for environmental health and to explore the possibility of forming a cohesive advisory group to serve at the national level, on behalf of the discipline.
A variance formula for gene mutation studies using agar plates
Authors: Javitz Harold S. 
Published: February 2007

AbstractPrevious attempts to derive a formula for the variance of the estimated mutant fraction have assumed (without providing justification) that variance components due to treatment, growth and dilution, and plating, are additive. We have derived a variance formula that does not depend on this assumption. Our formula also includes variability attributable to imprecise counting of cells to be plated in the non‐selective conditions.
Sister chromatid exchanges in the lymphocytes of control women, pregnant women, and women taking oral contraceptives: Effects of cell culture temperature
Authors: Ghosh Reita , Ghosh P. K. 
Published: February 2007

AbstractThe incidence of sister chromatid exchange (SCE) was investigated in the lymphocytes of control women, pregnant women, and women using oral contraceptives after culture at 37°C and 40°C. At 37°C, the mean frequency of SCE (MEAN ± S.E.) was found to be 7.91 ± 0.30 in pregnant women and 8.53 ± 0.29 in oral contraceptive users which were significantly higher than the SCE value of 5.56 ± 0.21 found in control women. Increase in growth temperature to 40°C elevated the SCE frequency to 11.86 ± 0.44 in pregnant women, 12.76 ± 0.46 in oral contraceptive users and 7.24 ± 0.26 in control women. These data indicate that there is a differential induction of SCEs following increased cell culture temperature in the lymphocytes of pregnant women and oral contraceptive users, compared with control women.
Heat shock and herpes virus: Enhanced reactivation without untargeted mutagenesis
Authors: Lytle C. David , Carney Paula G. 
Published: February 2007

AbstractEnhanced reactivation of Ultraviolet‐irradiated virus has been reported to occur in heat‐shocked host cells. Since enhanced virus reactivation is often accompanied by untargeted mutagenesis, we investigated whether such mutagenesis would occur for herpes simplex virus (HSV) in CV‐1 monkey kidney cells subjected to heat shock. In addition to expressing enhanced reactivation, the treated cells were transiently more susceptible to infection by unirradiated HSV. No mutagenesis of unirradiated HSV was found whether infection occurred at the time of increased susceptibility to infection or during expression of enhanced viral reactivation.
Sister chromatid exchange induction near the baseline with low doses of the alkylating agent ccnu
Authors: Best Robert G. , McKenzie Wendell H. 
Published: February 2007

AbstractSister chromatid exchange (SCE) and cell‐cycle kinetics were examined at near‐baseline levels in human peripheral lymphocytes exposed to low doses of the potent SCE inducer 1‐(2‐chloroethyl)‐3‐cyclohexyl‐1‐nitrosourea (CCNU), in vitro. A preliminary SCE dose‐response curve was determined with a broad range of doses of CCNU using a single donor. SCE induction was approximately linear over the entire dose range from 5 to 200 μM CCNU. Cell cycle kinetics were retarded in a dose‐dependent manner. A second dose‐response curve from the same donor was constructed using several doses of CCNU between 0.5 and 10 μM to evaluate linearity and uniformity of SCE response near baseline levels. SCE induction was approximately linear between 1.0 and 10.0 μM CCNU. Finally, SCE and cell‐cycle kinetics were examined in 12 donors at doses of 1.0, 5.0, and 10.0 μM CCNU to evaluate the reproducibility of near‐baseline SCE induction over a range of subjects. Cell‐cycle kinetics were retarded at all three doses with a highly significant increase in SCE frequencies at 5.0 and 10.0 μM CCNU. These data suggest that increases in SCE less than twice background can be reliable indicators of genotoxic exposure.
Genotoxic effects of some systemic pesticides: In vivo chromosomal aberrations in bone marrow cells in rats
Authors: Adhikari N. , Graver I. S. 
Published: February 2007

AbstractThe genotoxic effects of five pesticides (benomyl, 2,4‐D, dimecron, monocrotophos, and vitavax) were evaluated in the rat bone marrow cytogenetic assay. The spectrum of aberrations observed included chromatid breaks, chromatid fragments, ring chromosomes, dicentric chromosomes, and chromosome fragments. It was observed that 2,4‐D, dimecron, and vitavax were clastogenic, but the results obtained with benomyl and monocrotophos were equivocal.
Weak and unexpected mutagenicity to salmonella of the rat hepatocarcinogen methapyrilene
Authors: Ashby J. , Callander R. D. , Paton D. , Zeiger Errol , Ratpan Flora 
Published: February 2007

AbstractThe rat liver carcinogen methapyrilene is shown to be a selective mutagen to strain TA1535 of Salmonella typhimurium when tested in the absence of S9 mix and using the standard plate‐incorporation assay protocol. The activity observed was weak but was reproducible for a range of samples on many occasions of test and was not due to impurities. These data contrast with six earlier reports of the inactivity of this chemical in the Salmonella mutation assay.
Synergistic killing of bacteria and phage by polystyrene and ultraviolet radiation
Authors: Hoerter J. , Eisenstark A. 
Published: February 2007

AbstractFar‐untraviolet (254 nm) irradiation of bacteria and bacteriophage in polystyrene containers resulted in lower number of survivors, compared with irradiation in glass containers. This effect was not observed with near‐UV (300‐400 nm) irradiation.
Increased sister chromatid exchange associated with smoking and coffee consumption
Authors: Reidy John A. , Annest Joseph L. , Chen Andrew T. L. , Welty Thomas K. 
Published: February 2007

AbstractSister chromatid exchange (SCE) is a very sensitive cytogenetic assay for detecting exposure to chemical mutagens and carcinogens. One application of SCE is the monitoring of populations believed to be exposed to such agents. We have, however, relatively little knowledge about common lifestyle factors that may influence SCE and therefore complicate any study designed to examine the effects of exposure to genotoxins. In this study, we assessed the effect of cigarette smoking and coffee consumption on SCE. Smoking was associated with an increase of approximately 2 SCEs per cell and a decrease in cell proliferation. A positive linear relationship between SCE and coffee consumption was also observed. This effect was similar for smokers and nonsmokers. Additionally, the folk acid content of cell culture medium seemed to affect neither SCE nor cell proliferation.
Promutagen activation by freshly isolated and cryopreserved rat hepatocytes
Authors: Loretz Linda J. , Wilson Alan G. E. , Li Albert P. 
Published: February 2007

AbstractThe metabolic activation of promutagens by freshly isolated and cryopreserved rat hepatocytes was compared using the Chinese hamster ovary/hypoxanthine‐guanine phosphoribosyltransferase assay (CHO/HGPRT). Cryopreserved rat hepatocytes were equivalent to freshly isolated hepatocytes in their ability to metabolize dimethylbenz(a)anthracene (DMBA) and dimethylnitrosamine (DMN) to active mutagens. Similar dose‐response curves were observed using either freshly isolated or cryopreserved hepatocytes as activating systems after treatment with DMBA (0.1‐1 μg/ml) and DMN (0.075‐0.6 mg/ml). Our results suggest that cryopreserved hepatocytes are similar to freshly isolated hepatocytes as an experimental system for studies on promutagen activation.