Environmental and Molecular Mutagenesis - Legacy Tobacco ...

48 1989 EMS Abstracts
Notes express constitutively 10 proteins that are usually indudbie by Or . These proteins Include three
known enzymes : Mn-containing superoxide dismutase (to destroy Or), giucose-B-phosphate
dehydrogenase (to generate NADPH), and DNA endonuclease IV, which acts on a variety of oxidative
damages In DNA . These soxR mutants express Increased resistance to a variety of oxidative agents, and
these elevated resistances are only partly dependent on the sodA-encoded superoxide dismutase and the
n/o-enooded endonuclease IV . Consequently, the functions of the soxR regulon contribute In multiple
ways to cellular resistance, reflecting the complex modes of ceil damage caused by free radicals .
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HAVE THE COCA LEAVES AND BASIC COCAINE CONSUMERS A HIGH FREQUENCY OF CHROMO
SOME MUTATIONS . J . Descallleaux, M .L . Guwaro, L .A . Rodrrguez,M . Paredes, and M . Abarca.
Lab . Genet . Hum ., Fae . Ctenclas Biol6gioas, UNMSM, P .O . Box 14-0010, L(ma-PerG .
The number of coca leaves (CL) and basic cocaine (BC) oonsumers in the peruvian andeon region (CL)
and the capital ctty intiabitants (BC) (s In constant raise, (CEDRO,1987), the wnrks reported In relation
with the pharmacology effects of these hobitudes are oonhoverstals In the CL case, but all of
them hove appointed the BC as a very toxlc drug to the human health . We have selected two samples
of routinely consumers of CL and BC with their respective controls, In all of them, we have obtalned
4-6 ml of periptieral b lood to m ade a lymphory te culture and measure the chromosome aberro -
tions (CA) In first-dlvision metaphase oalls, and 5CE In seoond-diviston metaphase cells ; and exfolia
te cells from the oral m uoosa In order to estimate the frequency of mteronuclsi .
The results obtained In CL consumers showed a minor frequency of CA and SCE than the control -
group suggesting that the CL hove on enti-mutagenle property that may be a consequence of t he
high level of vitamine A(Pio6n-Rebtegu1,1976) knowing that this vitamine has on anti-mutogenle pro
perty (Grubbs et a1 .,1977) . But the mieronuelel frequency was higher In CL consumers, In this relation
it'is important to consider tha• the "ehoecheo" habitude (CL chswing) enolose the use of the
cal (CoO) alcaline and caustic substance, that would be the responstble of the aberront nuelel . In
the BC consumers, although our first results m ust be eonsidered as prei(minary, mainly because of the
s mall number of patients e xamined, they are showing an Inerese frequency of CA and SCE In the con
sumers than In the control group .
MUTAGENICITY OF TWO GIUCOCORTIC0I0St DEXAYiETFWSONE AND PREDNISOLONE
H .S . Dhillon and J .R . Singh, School of Life Sciences, Human Genetics Laboratory,
Guru Nanak Dev University, Amritsar (India)
Glucocorticoids are therapeutically very important as they possess strong
antiallergic and immunusuppressive properties . Keeping in view the mechanism of
action of these medicines which involves the interection of the drug with DNA
via specific receptor proteins, the mutagenic propertisa of two glucocorticoids -
Dexamethasone and Prednisolone - were investigated using Ames Salmonelly/S-9 test
and host mediated assay with mice and Salmonella tester strains (TA97e, TA98, TA
100 and TA1535) There was no significant increass or decre4se in the nueber of
His+ revertests/plate either with or without S-9 mix at the doses rangIng from
1 ug4to 1x10 ug/plate in the Ames test . Ho"r at higher doses (Sx10 ug and
1x10 ug/plete) the growth and number of His revertants/plate were inhibited
significantly . In the host mediated assay doses of the drugs tested were 1, 10
and 100 mg/kg bw . No significant positive results were obtained with either of
the drug, indicating that observed non-mutagenicity in the Salmonella straina is
not because of the insufficient metabolic degradation of the glucocorticoids in
the in vitro system but due to their inability to interact with the prokeryotic
DNA .
COMPARATIVE EFFICACY OF ASCORBIC ACID AND EXTRACT FROM
PHYLLANTHUS Mii BLICA FRUIT IN MODIFYING METAL CLASTOGENICITY
H .Dhir, S .Ghosh, Sharmila Ghosh, A .ohosh, A .K . Ghosh, S . Palit .
G . Talukder, A . Sharma, Human Genetics Unit, Centre for Advanced
Study Cell rx Chromosome Researeh, Department Botany, University
of Calcutta, Calcutta 700019, India .
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Fruits of Ph 1 an hus emblica L . contain Vitamin C and are Used
extensively n many me c na preparations of Ayurvedic and Unani
systems of medicine . Aqueous extravts of the fruit were fed to
laboratory mice for different periods to observe if the clasto- 'P
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