Environmental and Molecular Mutagenesis - Legacy Tobacco ...

94 1989 EMS Abstracts
http://legacy.library.ucsf.edu/tid/clb93d00/pdf
Notes observed (3 .1+1 .75'vs 3 .6+1 .1) . These results indicate that vanillin is also
effective in vivo syeteme and that vanillin may act at and before the S period of the
cell cycle. 1 Ohta et al ., Food Chem . Toxicol . 24,51(1986) . (2)Sasaki at al .,
Mutation Res ., 191,193(1987) .
268
IN VITRO CLASTOGENICITY OF 951 CHEMICAL SUBSTANCES . M . Ishidate,
Jr ., M . C . Harnois*, and T . Sofuni, National Institute of Hygienic
Sciences, Setagaya-ku, Tokyo (Japan), *Fellow, Japan Foundation
for Promotion of Cancer Research .
A literature review of 1964-1985 publications on the in vitro
clastogenicity of chemical substances resulted in data from 240
reports on 951 substances . Of these 951, 447 were consistently
positive either with or without activationj 417 were negative
without activation but not tested with activationi 30 were
consistently negative when tested both waysi and 53 gave variable
results . The variability was related to cell type, presence of
activation mechanisms and treatment schedule . Addition of an
activation system reduced the variation among different cell typesr
no one cell type appeared to be superior for testing all clastogens .
The conce%tration at which substayes tested positive ranged from
4 .3 x 10 (trenimon) to 6 .9 x 10 mM (acetone) . Generally, there
was an inverse relationship between the concentration required
to induce aberrations and the frequency of exchange-type aberrations
produced by a chemical at its maximum effect dose . The relevance
of tests conducted at high concentrations is considered, and caution
urged in the interpretation of test results obtained under
physiologically stressful conditions .(Mutation Res .,195, 151, 1988)
MOTAGENICITY AND ANTIHUTAGENICITY IN AIR-BORN PARTICULATES
269
Hiroko Iwado1'2 . Mitsuko Naitol Hikoya Hayatsu2, lOkayama Prefectural Research Center
of Environmental and Public Health, Uchio, Okayama 701-01, 2Faculty of Pharmaceutical
Sciences, Okayama University, Tsushima, Okayama 700 (Japan)
Air-borne particulates collected by a high-volume air sampler in a suburban area of
Okayama City were extracted with methanol under ultrasonic vibration . The residue
obtained on evaporating the solvent was dissolved in a small amount of dimethylsulfoxide
and the solution was divided into two portions . One was submitted as such to
the Ames test for assaying mutagenicity (sample 1) . Another portion was suspended in a
large volume of water and treated with blue cotton to adsorb polycyclic compounds to
the cotton . A methanol-ammonia eluate of the blue cotton (sample 2) and the aqueous
portion that remained after the blue cotton treatment, after evaporation to dryness
(sample 3), were also examined . 1 shoved mutagenicity towards S . typhimurium TA98 in
the presence of S9-mix in a dose-responding linearity up to 27 m3 air-volume equivalent ;
however, the colony number stayed constant in the dose range between 27-270 >l3 . In
contrast, 2 gave a linear dose-response up to 270 m3 . Although the numbers of
revertant colonies found were about 2-times greater with 1 than vith .2 in the range
lower than 27 m3, the numbers obtained with 2 were much greater than those with 1 in
the higher dose range . These results suggest that antimutagenic factors were present
in 1 . In fact, when 3 was mixed with 2, a strong suppression of the mutagenicity was
observed . The antimu[agenic factors pieaent in 3 were capable of inhibiting the
mutagenicity of benzo(a)pyrene and that of 2-nitrofluorene . (Supported by Nippon Life
Insurance Foundation .)
270
INFLUENCE OF UMUC ON EMS-INDUCED YUTAOEBESIS IN E . COLI DEFICIENT IN
MISMATCH REPAIEE- C . Janion, and E . Orsesiuk, InetiTaTe- of Biochemistry
and Biophysics, Polish Academy of Sciences, Warsaw, Poland .
we have compared mutagenio aetivit and speeifieity of EMS (ethyl
methaneaulfonate) in ;gc~ 2497( +~~ ) and its derivative
strains : EC2401(mutS+~um v _~ Y1(mu uC') and EC2402( ut~S'umuC-) . It
has been found tE~"-t s ite of mu at on (based on ezam3nation of the
phenotypes of Arg+ revertants) and the dutagenio specificity (based on
ability of the Arg+ revertants to support growth of aaber and ochre T4
bacteriophages) depends on um C, but only in the mutS-- mismatch repair
de icient strain . The maJor+it~'of EIB-induoed Arg'r'~3vertants of AB
24~7, EC2401 and EC2402, show the phenotype - Arg+His-Thr ; whereas
the majority of EMS-induced Arg+ rewertants of Y1 show the phenotype
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