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The gas station attendants are exposed daily to chemical agents that compose gasoline, such as BTEX (benzene, toluene, ethylbenzene, and xylene), and the exposure to these agents can cause a variety of effects on the human health. Among the various possible cell alterations associated with these exposures are the formation of micronuclei and of binucleated cells which are used as indicators of clastogenic action. Benzene, the main carcinogenic agent, is metabolized to more soluble forms and easily excreted by isoenzymes of cytochrome P450, such as CYP1A1. The CYP1A1 gene is highly polymorphic and one of its allele variations can be detected by the use of restriction endonucleasis MspI and is originated by the transition of a thymine by a cytosine (3798T>C), resulting in the polymorphic allele CYP1A1*2A. The objective of this study was to evaluate the cytogenetic damage induced by the exposure to BTEX and to associate it with the polymorphisms of the CYP1A1 and NR1I3 genes. Samples of exfoliated cells from the oral mucosa of 27 gas station attendants and from a control group were collected. The results found show that the group exposed to BTEX presents significantly higher alterations than those in the control group for micronuclei (MN; 6.85 ± 1.33 vs. 2.96 ± 1.91, P < 0.001) and for the total of nuclear alterations observed (MN + binucleated cells (BNC); 9.59 ± 4.73 vs. 5.07 ± 2.21, P < 0.001). When comparing the cytological alterations and the genotypes among the exposed individuals for the polymorphism 3798T>C of the CYP1A1 gene, homozygotes TT present MN + BNC significantly higher than carriers of the allele C (10.88 ± 5.36 vs. 5.33 ± 2.52, P = 0.028). No association was observed in the control group or for the NR1I3 gene. These results show that molecular and cytogenetic data can be used in the future as tools to monitor individuals exposed to such compounds.

Ovarian development, oviposition, larval eclosion, ornithine decarboxylase (ODC) activity, ovarian, testis and ejaculatory apodeme measurements (length, width, and area), and the number of spermatozoa of Anastrepha fraterculus (Wiedemann) were analyzed at alternating (20º/6ºC and 20º/13 o C) and constant (6 o C; 25 o C) temperatures. Life span and life expectancy were also analyzed for both genders. All the results suggest that temperature, especially alternating temperatures, increase not only male and female reproductive potential but also their life span and life expectancy. These changes can be a powerful strategy triggered by A. fraterculus as a means to survive the stressful temperature conditions found in winter in the apple production region in Brazil, enabling this species to increase its population density and cause apple damage when spring begins.Key words: reproductive potential, Tephritidae, temperature. RESUMO Efeitos de temperaturas constantes e alternadas no potencial reprodutivo, longevidade e expectativa de vida de fêmeas e machos de Anastrepha fraterculus (Wiedwmann) (Tephritidae)O desenvolvimento ovariano, ovoposição, eclosão larval, atividade de ornitina descarboxilase (ODC), medidas de largura, comprimento e área do ovário, testículo e apódema ejaculatório e número de espermatozóides de Anastrepha fraterculus (Wiedemann) foram analisados em temperaturas alternadas (20º/6 o C e 20º/13 o C) e constantes (6 o C e 25 o C). A longevidade e a expectativa de vida também foram analisadas em ambos os sexos. Todos os resultados sugerem que a temperatura baixa e principalmente as temperaturas alternadas afetam não somente o potencial reprodutivo de machos e fêmeas, mas também sua longevidade e expectativa de vida, prolongando-as. Essas mudanças podem ser uma poderosa estratégia usada por A. fraterculus para sobreviver às condições estressantes de temperatura observadas no inverno na região produtora de maçãs, tornando-as capazes de aumentar sua densidade populacional e causar dano à maçã no início da primavera.Palavras-chave: potencial reprodutivo, Tephritidae, temperatura. Braz. J. Biol., 62(4B): 775-786, 2002 776 CARDOSO, V. V. et al.

Genetic damage during the prenatal period can provoke important neoplastic alterations and other diseases in postnatal life. Beta-carotene (ßC) is considered to be one of the most important anticarcinogens in the diet and can protect mammalian cells against genotoxic events. As carrots are important dietary source of ßC, we decided to test the effect of fresh carrot juice (CaJ) on cyclophosphamide (CP)-induced genotoxicity in maternal and fetal erythropoietic tissues. The treatment with CaJ started on the 7th day of the pregnancy of BALB/c female mice. We observed, on the 16th gestational day, that this treatment did not modify the spontaneous frequency of micronucleated polychromatic erythrocytes (mPCE) in the bone marrow of the females nor in the livers of their fetuses. The mPCE frequency observed 24 h after an intraperitoneal injection of CP (40 mg/kg) on the 15th day was significantly lower in CaJ-pretreated pregnant female bone marrow and in the liver of their fetuses than those observed in the group treated with CP only. These results demonstrate the presence of natural anticlastogens in carrots.
O dano genético durante o período pré-natal pode ser uma importante fonte de alterações neoplásicas e de outras doenças durante a vida pós-natal. O beta-caroteno (ßC) é considerado um dos mais importantes anticarcinógenos da dieta e pode proteger células de mamíferos contra eventos genotóxicos. Como a cenoura é a fonte clássica do ßC, nós decidimos testar a modulação do suco de cenoura fresco (CaJ) sobre a genotoxicidade induzida pela ciclofosfamida (CP) no tecido eritropoiético materno e fetal. O tratamento de fêmeas BALB/c com o CaJ ocorreu desde o 7º dia gestacional. Nós observamos, no 16º dia gestacional, que tal tratamento não modificou a freqüência espontânea de eritrócitos policromados micronucleados (mPCE) na medula óssea materna ou no fígado fetal. Quando fêmeas prenhes pré-tratadas com o CaJ receberam uma injeção intraperitoneal de CP (40 mg/kg) no 15º dia gestacional, 24 h depois foi observada uma freqüência de mPCE significativamente menor do que a observada no grupo tratado somente com a CP, tanto na medula óssea materna como no fígado fetal. Estes resultados indicam a presença de anticlastógenos naturais na cenoura

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