Environmental and Molecular Mutagenesis - Legacy Tobacco ...

comparable with the effedEa in the parent wild type cell line . Their cellular
incorporation of H3-hypoxanthine was enhanced in the presence of aminopterin,
but decreased with L-asaserine indicating that they were PRPP mutants . According
to these results, we suggest that reversion of these 2 6TGrAATr mutants may
occur by a gene amplification mechanism and that this process may be facilitated
by 5AC treatment .
665
MUTAGENICITY AND CARCINOGENICITY OF NITROSATED FISH SAUCE
R .F .Zhang, D .J .Deng, Y .Chen, H .Y .Wu, S .Jin, S .X .Zhu and Y .P .Liu
Beijing Institute for Cancer Research, Beijing, China
Fish sauce, a traditional daily use seasoning, was collected from
Changle county in Fujian province, where the mortality of gastric cancer
is the highest in China . To evaluate the risk of taking fish sauce for
the high incidence of this disease in that area, mutagenicity and carcinogenicity
of the fish sauce were stidied . By the Ames test(S . typhimurium
TA100) and in vitro SCE and micronucleus tests in V79 cell 11ne,
direct mutagenicity(-S9) appeared in the ethyl acetate extract after
nitrosation with NaN02 . A dose response relationship was obtained . The
highest response was observed in the extracts of acidic nitrosation(pH
2 .0) and the samples from the villa e with the highest mortality of
gastric cancer . After 0,1m1 extract~corresponding to 1 .Oml of nitrosated
fish sauce) was given to each of the studied new born Wistar rats by
gava e for 3 consecutive days, marked dysplasia was observed at the 4th
week~in 5/5 rats) and adenocarcinoma developed(in 1/5 rat) at the 16th
week in the glandular stomach . It indicated that some nitrosable precursors
of direct-acting mutagenic/carcinogenic N-nitroso compounds must be
contained in the fish sauce and it may play important role, after nitrosation,
in the causes of gastric cancer and its precancerous lesions of
stomach in Changle county residents . Detection of these compounds is now
undertaking. f
666 "
A METHOD TO GET THE BACTERIOPHACE SPOT CLEAR IN INDIRECT SOS TEST
Zhao Zezhen, Wel Lirhent Haans Mlntlt Hebet Cancer Instltutes P .R .China
It has been provod that, among oe many methods te check the mutagens
In environment, Indirect SOS Test, I,e, bacterlephage Inductlon methed,
Is a quick, sensitive and reliable ene . The methed is te mix CY6027s a
lysesenic bacterlat with GY4016s a Indlcatin{ bacteria which Is sensitive
to the bacterlophage released by Gy60279 In a sub-solid culture
medium according te a certain preportlon . While meeting mutatens, the
lysogenic bacteria wlll release bacterlephase dissolution indicating
bacteria, then bacterlophate spat will appear on the culture medlum
which Is surrounded by muddy bacterlafur, However, the centrast between
bacterlophage spot and bacterlafur Is net cloar enough te observe and,
especlally, to take photo or make lantern slide . In light ef the prlnciple
that, in the course of grewthr colour bacillus Gy4016 and Gy6027
can break down glucose and produce acid which can make the Indlcater
change colour . We make an improvement on the original methed, that los
add 2m1 of 2% disinfected (low pound) glucose selutlen and iml of 0,6%
disinfected bromecresel purple solution te 60m1 of ineiting sub-salid
culture medlumq then put the two test bacteria liquid to the mixture
selutlon, which will make the culture medium chan{e to blue coleur .
Other test steps are simillar te the original, Comparing the new method
with the orisinalt the new test results show to Increase the contrast
between bacterlephage spot and bacterlafur . And though It, we have succeeded
in taking phste and making lantern slide,
667
OBSERVwTION OF THE EYES ON FIFTY WORKERS OCCUPATIONALLY
EXPOSBD TO DIMETHYL SULFATE
rien~iang-Zhao .Electricity centre Hospital in NE China .Shenyang(China)
ime.thyl sulfate is an important raw material of chemical industry .
Its decomposing products methanol and sulphuris acid may impair cornea,
conjunctiva etc . Cases of acute poisoning of dimethyl sulfate have
been reported,however,observation of the eyes in workers occupationally
exposed to dimethyl sulfate of lower concentration for a long time
http://legacy.library.ucsf.edu/tid/clb93d00/pdf
1989 EMS Abstracts
Notes
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