bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytotoxicity and mutagenicity of coal oils in the CHO/HGPRT assay
Authors: Demarini David M. , Brimer Patricia A. , Hsie Abraham W. 
Published: February 2007

AbstractWe used the Chinese hamster ovary cell/hypoxanthine‐guanine phosphoribosyl‐transferase (CHO/HGPRT) assay to determine the cytotoxicity and mutagenicity of a crude coal oil, the neutral fraction of this crude, and the following three subtractions of the neutral fraction: aliphatic, neutral polar, and a subtraction composed of polycyclic aromatic hydrocarbons plus neutral nitrogen heterocyclics. We also studied the cytotoxicity and mutagenicity of a blend of light and heavy coal‐derived fuel oils before and after hydrogenation. All seven mixtures were highly cytotoxic to CHO cells, but the addition of S9 reduced the cytotoxicity. Also, hydrogenation reduced the cytotoxicity of the blend of coal‐derived fuel oils. Although highly cytotoxic, none of the seven mixtures induced a clear mutagenic response in the CHO/HGPRT assay. However, previous work has shown that all of the mixtures except the aliphatic subfraction and the blend after hydrogenation are mutagenic in the histidine‐reversion assay in Salmonella typhimurium. Based on chemical analyses of the mixtures, the differential sensitivity of Salmonella and CHO cells to nonmutagenic cytotoxins, and studies of the neutral fraction to which additional benzo[a]pyrene had been added, we conclude that the disparity between the results in Salmonella and those obtained in the CHO/HGPRT assay is probably due to the much greater sensitivity of CHO cells (relative to Salmonella) to the cytotoxins in these coal oils. This sensitivity, coupled with the low concentrations of mutagens relative to nonmutagenic cytotoxins in the coal oils, prevents exposure of the cells to concentrations of the mutagens in the mixtures that are high enough to be quantified in the CHO/ HGPRT assay.
Use of aroclor 1254‐induced rat liver homogenate in the assaying of promutagens in chinese hamster ovary cells
Authors: Li A. P. 
Published: February 2007

AbstractSeven promutagens belonging to two chemical classes—polycyclic aromatic hydrocarbons (PAHs) (benzo[a]pyrene, dimethyl benz[a]anthracene, 3‐methylcholanthrene, fluoranthene) and alkyl nitrosamines (dimethyl, diethyl, and dibutyl nitrosamine)—were studied in Chinese hamster ovary (CHO) cells. Findings of practical importance in the use of Aroclor 1254‐induced rat liver homogenate (S9) in the CHO/hypoxanthine‐guanine phosphoribosyl transferase (HGPRT) mutation assay were made. Our novel findings are (1) the inclusion of CaCl2 in the S9 cofactor mixture dramatically decreased the cytotoxicity of S9, and (2) different S9 optimum concentrations were observed for structurally similar promutagens. The inclusion of CaCl2 in the S9 cofactor mixture and the testing of each chemical of unknown S9 requirement at several S9 concentrations are therefore recommended for assaying promutagens in the CHO/HGPRT mutation assay.
Role of oxygen radicals in tumor promotion
Authors: Kensler Thomas W. , Trush Michael A. 
Published: February 2007

AbstractTumor promoters provoke the elaboration of oxygen radicals by direct chemical generation and through the indirect activation or alteration of cellular sources including membrane oxidases, peroxisomes, and electron transport chains in mitochondria and endoplasmic reticulum. Although direct measurement of amplified oxygen radical production in response to tumor promoters in target tissues remains problematic, studies with scavengers of reactive oxygen species demonstrate inhibition of biochemical and biological sequelae of tumor promoter exposure and provide strong presumptive evidence for oxygen radical involvement in this late stage of carcinogenesis. The critical macromolecular targets for these oxygen radicals remain undefined; however, they may include lipids, DNA, DNA repair systems, and other enzymes.
The effect of female strain on identification of male mice carrying reciprocal translocations
Authors: Sheu C. W. , Wang J. N. , Moreland F. M. 
Published: February 2007

AbstractChemicals capable of inducing heritable chromosomal effects may be detected by the mouse heritable translocation test, which is based on the detection of a specific type of transmissible abnormality, namely, reciprocal translocation. Since mice carrying such a chromosomal abnormality usually have reduced fertility, they may be identified on the basis of fertility data. In the present study, the efficiency of two female strains for identifying CD‐1 male translocation heterozygotes was examined. Thirty‐three 10‐wk‐old CD‐1 male mice were injected IP with triethylenemelamine (0.025 mg/kg/day) 5 days a wk for 5 wk. The treated males were then mated to untreated CD‐1 females for 2 wk to produce progeny. The F1 males were raised to maturity, tested for fertility by using two female strains (CD‐I and B6C3F1), and analyzed cytogenetically. The cytogenetic analysis confirmed that 41 males were translocation heterozygotes and 125 were normal. Examination of the fertility data showed that in the test with CD‐I females all translocation heterozygotes were identified but 19 normal mice were identified as potential translocation carriers because of decreased fertility. In the test with B6C3F1 females, five translocation heterozygotes were not identified on the basis of fertility data, and 11 normal mice were misclassified as potential translocation carriers.
Aneuploidy induced by bleomycin in oocytes of Drosophila melanogaster: Studies with the aneuploidy pattern method
Authors: Traut H. 
Published: February 2007

AbstractThe induction of aneuploidy (numerical chromosome aberrations) in oocytes of Drosophila melanogaster by the antitumor drug bleomycin (BLM) was studied with the “aneuploidy pattern method.” The aneuploidy pattern obtained after feeding BLM at a concentration of 50 μg/ml to Drosophila females resembles the pattern obtained after X‐irradiation (3,000 R). This emphasizes the radiomimetic nature of BLM. In addition, new control material is presented. The new control pattern agrees well with that obtained earlier.
Screening program theory: Decision functions and protocols
Authors: Denniston Carter 
Published: February 2007

AbstractA screening program is defined to include a set of tests, a decision function, and a protocol. The major characteristics of a screening program are the error rates of the individual tests, the overall error rates of the program, the costs of the individual tests, and the overall program costs. It is shown how to calculate the program error rates for any given decision function. The concept of a screening protocol is developed and a method for enumerating all protocols of a given decision function is given. A given protocol has two calculable costs: the average cost of testing a mutagen and the average cost of calculating a nonmutagen. A method for calculating these costs for any protocol is given. All decision functions utilizing up to five tests are enumerated.
Testing of 24 food, drug, cosmetic, and fabric dyes in the in vitro and the in vivo/in vitro rat hepatocyte primary culture DNA repair assays
Authors: Kornbrust Douglas , Barfknecht Thomas 
Published: February 2007

AbstractTwenty‐four dyes currently or previously used in the food, drug, cosmetic, and textile industries were tested in the in vitro rat hepatocyte primary culture/DNA repair (HPC/DR) assay and, to a limited extent, in the in vivo/in vitro HPC/DR assay. The positive control, Solvent Yellow 3 (o‐aminoazotoluene), and five other dyes (4‐dimethylaminobenzeneazo‐1 ‐naphthalene, 4‐dimethylaminobenzeneazo‐2‐naphthalene, Direct Blue 53, Acid Blue 9, and 4‐dimethylaminostilbene) induced DNA repair in rat hepatocytes both in vitro and in vivo, while 13 of the dyes (Food Red 1, Food Red 5, Food Orange 4, Food Red 7, Acid Red 14, Acid Red 27, Pigment Red 53, Acid Yellow 23, Food Black 1, Food Green 3, Acid Red 51, Acid Blue 74, and Natural Red 4) did not produce any detectable DNA repair in either the in vitro or in vivo/in vitro assays. Direct Blue 14 had weak activity in vitro but none was detected in vivo. In contrast. Solvent Yellow 5 was not active in vitro, but produced a weak positive response in vivo. Negative responses were also obtained for Solvent Yellow 14 and Acid Green 5 in the in vitro assay, whereas the responses produced by these dyes in the in vivo/in vitro assay were judged to be equivocal. An equivocal response was also obtained for Direct Red 28 in the in vivo/in vitro assay as well as in the in vitro assay. These findings provide information about the potential genotoxicity of a number of dyes for which previous genotoxicity data has been inconsistent or inadequate. For some dyes (eg, Solvent Yellow 5), discrepancies between the results obtained in the in vitro and in vivo/in vitro assays may implicate a role for intestinal microflora in their metabolic activation.
Influence of retinol on carcinogen‐induced sister chromatid exchanges and chromosome aberrations in V79 cells
Authors: Qin S. , Batt T. , Huang C. C. 
Published: February 2007

AbstractThe influence of retinol (Rol) on sister chromatid exchanges (SCE) in V79 cells induced by six indirect and two direct carcinogens, and on chromosome aberration (CA) in V79 cells induced by four indirect carcinogens were studied. The indirect carcinogens used were aflatoxin B1 (AFB), cyclophosphamide (CPP), benzo(a)anthracene (BA), benzo(a)pyrene (BP), 9,10‐dimethyl‐1,2‐benz(a)anthracene (DMBA), and 3‐methylcholanthrene (MCA). The two direct carcinogens were ethyl methane sulfonate (EMS) and N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG). Rol effectively inhibited SCE and CA induced by AFB and CPP in a dose‐dependent manner, but it had no effect on SCE induced by BA, BP, DMBA, MCA, EMS, and MMNG. To the contrary, Rol had an enhancing effect on CA induced by BP and DMBA. Altering the concentration of the metabolic activation system‐S9 mix had a significant effect on inhibition of AFB and CPP induced SCE by Rol. A high ratio of Rol/S9 mix resulted in a maximum effect of inhibition of SCE frequencies. Using low concentrations of S9 mix and various doses of Rol close to physiological levels (2μ/ml and below) demonstrated a dose‐dependent inhibition of AFB‐ and CPP‐induced SCE. The possibility that Rol exerts its anticarcinogenic effects by inhibiting certain forms of the cytochrome P‐450 isoenzymes required for activation of precarcinogens, such as AFB and CPP but not those enzymes required by BA, BP, DMBA, and MCA, is discussed.
Increased mutagenicity of chromium compounds by nitrilotriacetic acid
Authors: Loprieno N. , Boncristiani G. , Venier P. , Montaldi A. , Majone F. , Bianchi V. , Paglialunga S. , Levis A. G. 
Published: February 2007

AbstractNitrilotriacetic acid trisodium salt (NTA), which is a substitute for polyphosphates in household laundry detergents, and N‐nitrosoiminodiacetic acid (NIDA), a derivative of NTA produced by metabolism of soil microorganisms, were tested for in vitro mutagenicity in bacteria and yeasts. No gene reversions in five strains of Salmonella typhimurium (TA1535, TA1537, TA1538, TA98, and (TA100), no forward gene mutations in Schizosaccharomyces pombe P1, and no mitotic gene conversions at two loci in Saccharomyces cerevisiae D4 were induced by NTA (up to 870 μ/plate or 40 μ/ml) and NIDA (up to 2,000 μ/plate or 1,000 μ/ ml), independently of the presence of rat liver metabolic activation. The influence of NTA on the mutagenic and clastogenic activity of several chromium compounds was examined in the Salmonella/microsome assay and in the sister chromatid exchange (SCE) assay in mammalian cell cultures (Chinese hamster ovary [CHO] line). NTA does not affect the genetic inactivity of water‐soluble Cr(III) (Cr2[SO4]3) and the direct mutagenicity of soluble Cr(VI) (Na2CrO4,K2Cr2O7) compounds. The very insoluble Cr(VI) compounds PbCrO4 and PbCrO4. PbO are instead clearly mutagenic in the Salmonella/microsome assay (TA 100 strain) only in the presence of NTA or NaOH. The mutagenicity of lead chromates is correlated with the amounts of Cr(VI) solubilized by NTA or alkali, as detected by the colorimetric reaction with diphenylcarbazide and atomic absorption spectrophoto‐metry. In the SCE assay, the insoluble lead chromates are directly clastogenic owing to prolonged treatment conditions and cellular endocytosis. The chromosome‐damaging activity of PbCrO4 is significantly increased by NTA but not by NaOH.
HGPRT− Mutants of V79 cells that revert specifically by base pair substitution and frameshift mutations
Authors: Stone‐Wolff Donna S. , Klein Catherine B. , Rossman Toby G. 
Published: February 2007

AbstractIn order to determine the mutagenic specificity of mutagenic and carcinogenic agents in mammalian cells, a reversion system capable of distinguishing between frameshift mutations and various kinds of base pair substitutions would be useful. We report here a method for the isolation and characterization of HGPRT− Chinese hamster V79 cell mutants that might form the basis for such a system. Two mutants of different specificity have been partially characterized. DEW‐1, isolated following N‐methyl‐N'‐nitro‐N‐nitrosoguanidine (MNNG) treatment, is revertible by the base pair substitution mutagens MNNG and ethyl methanesulfonate (EMS), but not by frameshift mutagens. DSW‐3, isolated following ICR‐191 treatment, is specifically reverted by frameshift mutagens, but not by EMS or MNNG. With the further characterization of these and other mutants, it should be feasible to determine not only whether an agent is mutagenic in V79 cells, but also to determine the type(s) of mutation(s) it produces.
Interaction of nitrilotriacetic acid with heavy metals in the induction of sister chromatid exchanges in cultured mammalian cells
Authors: Montaldi A. , Zentilin L. , Venier P. , Gola I. , Bianchi V. , Paglialunga S. , Levis A. G. 
Published: February 2007

AbstractThe ability of nitrilotriacetic acid trisodium salt (NTA) to induce sister chromatid exchanges (SCE) and to influence the induction of SCE by heavy metal compounds was evaluated with mammalian cell cultures.In accordance with the generally negative results obtained by other investigators on the mutagenic effects of NTA, no increase of SCE frequency was observed in Chinese hamster cells (CHO line) or in primary cultures of mouse (BALB/c and BALB/Mo strains) lymphocytes, after treatment with NTA at subtoxic concentrations (2 × 10−3 M and 10−3 M, respectively).The induction of SCE by salts of heavy metals (Cd, Hg, Ni, Pb) was evaluated with CHO cells. Soluble (CdCl2, HgCl2, NiCl2, Pb [CH3COO]2) and insoluble (CdCO3, HgCl, NiCO3, PbSO4) compounds were tested, and, with the exception of Pb(CH3COO)2, all were found to increase the frequency of SCE.NTA apparently did not affect the ability of the soluble metal compounds to induce SCE, but it significantly increased the frequency of SCE induced by treatment with all the insoluble salts.
Comparison of mutagenicities in a salmonella reversion assay mediated by uninduced hepatocytes and hepatocytes from rats pretreated for 1 or 5 days with aroclor 1254
Authors: Hass B. S. , Heflich R. H. , Shaddock J. G. , Casciano D. A. 
Published: February 2007

AbstractHepatocytes prepared from rats pretreated for 5 days with 500 mg/kg Aroclor 1254 were found to be unsuitable for use in a modified Salmonella mutagenicity assay. These hepatocytes exhibited low viability, did not readily attach to plastic culture dishes, and produced mutagenicity responses with benzo[a]pyrene (B[a]P) and 2‐aminofluorene (2AF) that were greatly enhanced by the addition of an NADPH‐regenerating system (NADPH‐RS). Shortening the Aroclor pretreatment time to 1 day resulted in hepatocytes that exhibited high viability and readily attached to plastic culture dishes. These hepatocytes produced higher numbers of revertants when used to assay the mutagenicities of B[a]P and 2AF than were produced using hepatocytes from animals that were pretreated for 5 days. These reversion frequencies were also higher than those produced using uninduced hepatocytes and were much less affected by the addition of NADPH‐RS than were the reversions mediated by the 5‐day preinduced hepatocytes. Liver homogenate postmitochondrial fractions (S9s), which were prepared from rats pretreated with Aroclor for 1 or 5 days, were nearly equal in their ability to mediate the mutagenicity of B[a]P and 2AF in the Salmonella/microsome reversion assay. Qualitative differences between the S9‐ and hepatocyte‐mediated mutagenicity of 2AF were found, however. These results indicate that employing hepatocytes from rats pretreated with Aroclor for 1 day, rather than 5 days, results in an enzymatically induced, more‐intact cell population that is capable of detecting the mutagenicity of B[a]P and 2AF in a modified Salmonella reversion assay.
Evaluation of laser dye mutagenicity using the ames/salmonella microsome test
Authors: Wuebbles Barbara J. Y. , Felton James S. 
Published: February 2007

AbstractTwenty‐five laser dyes and four analogs were tested for mutagenicity in the Ames/Salmonella test. Seven dyes and two analogs gave positive mutagenic responses with bacterial strains TA1538 and TA98. Of two widely used families of laser dyes (coumarins and rhodamines), four coumarin samples, but none of the rhodamine samples, were mutagenic. All mutagenic compounds require enzyme activation for positive response except two terphenyl analogs, which are mutagenic with or without activation. Using high‐performance liquid chromatography (HPLC), it was determined that five mutagenic dye samples had multiple components. The dyes themselves may not be the mutagenic agents in all cases (as with Nile Blue) but may contain impurities that are mutagenic. One dye, adicyanome‐thylene (DCM) (≥95% pure), was mutagenic at doses below 0.5 μg/plate on strains TA1538 and TA98. DCM also induced reversions in strains TA96, TA97, TA100, TA102, and TA104, although less efficiently. This study indicates the need for further toxicological testing of these types of compounds. The mutagenic components of these dye mixtures, whether it is the dye or a contaminant, presents a possible hazard to those handling them. Therefore, practices and procedures for the safe handling of specific dyes should be reviewed in light of these findings.
Comparisons of mutation induction by six monocyclic aromatic amines in salmonella typhimurium tester strains TA97, TA1537, and TA1538
Authors: Shahin Majdi M. , Chopy C. , Lequesne N. 
Published: February 2007

AbstractThe mutagenicity of six monocyclic aromatic amines (2,4‐diaminoanisole, 2,4‐diaminoethoxybenzene, 2,4‐diaminopropoxybenzene, m‐phenylenediamine, 2,4‐diaminotoluene, and nitro‐p‐phenylenediamine) was investigated in Salmonella typhimurium strains TA97, TA1537, and TA1538 in the presence of two different amounts of Aroclor 1254‐induced S9 preparations. Strain TA1538 was found to be the most responsive of the three strains with this group of compounds. Regarding the other strains, TA1537 responded to three of the compounds better than strain TA97, if one calculates responsiveness as the fold‐increase in numbers of revertants per plate. However, if one calculates the number of revertants per nanomole or compares the number of induced revertants per plate, TA97 was more responsive than TA1537 for all six compounds. Comparisons of mutagenesis from tests involving strain TA97 are complicated by the large variations in spontaneous mutation frequencies in this strain. The amount of S9 per plate is another important variable in tests of monocyclic aromatic amines; in general, more revertants are detected when the S9 mix contains 10% S9 than when it contains 4% S9. Nevertheless, in all our tests of 2,4‐diaminoanisole, 2,4‐diami‐noethoxybenzene, and 2,4‐diaminopropoxybenzene, the same relationship between chemical structure and mutagenic activity was observed. In all three strains, the mutagenic responses become less when the alkoxy substituent on the molecule becomes larger.
Sister chromatid exchanges in adult epileptic patients on phenytoin therapy
Authors: Schaumann Blanka , Johnson Sue Barden , Wang Nancy , van Brunt Suzanne 
Published: February 2007

AbstractSister chromatid exchanges (SCE) were studied in lymphocyte cultures of 12 adult male epileptic patients on long‐term monotherapy with phenytoin (PHT) and of matched controls. Significantly increased frequency of SCE was observed in the epileptic patients as a group and in almost all individuals, indicating a detectable chromosome damaging effect of PHT therapy on its human users.
Schistosome related cancers: A possible role for genotoxins
Authors: Gentile James M. 
Published: February 2007

AbstractSchistosomiasis has long been associated with cancer. This association is most prevalent between Schistosoma hematobium and bladder cancer. Numerous theories have been proposed to explain the causal link between the parasite infestation and the ensuing neoplasia. One theory that has not received as much attention as others, however, is the role of genotoxins in the neoplastic process. Considering the substantial amount of supportive evidence for the cocarcinogenic effects of schistosomes, concern for the health effects resulting from exposure of infested individuals to either exogenous or endogenous genotoxins is certainly warranted.
Basic principles of laboratory safety
Authors: Nemchin Robert G. , Brusick David J. 
Published: February 2007

AbstractLaboratory safety is a concern to scientific personnel conducting research or safety testing, laboratory directors responsible for institutional liability for employees, and to individuals working or residing near the laboratory.A strategy for safe laboratory operations requires an understanding of industrial hygiene, engineering, and the regulations associated with the use of hazardous chemicals.This review describes many of the basic principles involved in laboratory safety. It provides general information on the use of personal protective equipment, selection of laboratory safety equipment, laboratory design, disposal of hazardous waste, and the regulations and guidelines affecting laboratory operations.