ABSTRACT
Pterygoplichthys pardalis is an armored catfish native to South America and an important resource for the ornamental fish industry. Recently, several exotic populations have been introduced into rivers on five continents. Despite its commercial and environmental importance, P. pardalis is poorly studied from a genetic perspective. In this study, we analyzed the karyotype of P. pardalis from the Amazon River and molecular variations in the mitochondrial gene Cytochrome oxidase I (COI) between native and exotic populations. The karyotype presented diploid number 2n = 52 and NF = 100 without cytogenetic variation between males and females. Nucleolus organizer regions (Ag-NOR) in the distal region of the long arm of pair 12 coincided with the 18S hybridization signal, whereas 5S was syntenic to this chromosome but localized in the short arm. The constitutive heterochromatin was restricted in the distal regions of pairs 4, 12, 25, and 26. Telomeric probes showed only distal hybridization signals. The karyotype of P. pardalis diverged from that of its congeners, and COI molecular variation revealed four haplotypes. The Philippine population revealed the greatest diversity with three haplotypes, while haplotype H1 was the most abundant and observed in both native and exotic populations. This new genetic data contributes to species management and provides useful information from an aquaculture perspective.
ABSTRACT
Introdução: Profissionais frentistas encontram-se em situação de risco tóxico pela exposição constante aos vapores dos combustíveis. O benzeno, presente na gasolina, é considerado cancerígeno e prejudicial à saúde desses trabalhadores Objetivo: Avaliar os efeitos genotóxicos decorrentes da exposição ocupacional em células esfoliativas da mucosa oral de frentistas do município de Santarém, Pará; e determinar a taxa de adesão ao uso de equipamentos de proteção individual por esses colaboradores. Métodos: Um total de 126 frentistas, distribuídos em 6 grupos contendo indivíduos expostos foram comparados ao grupo controle utilizando a técnica do ensaio de micronúcleos em células da mucosa oral coradas com as técnicas de Feulgen/Fast-green. Resultados: Os frentistas apresentaram maior frequência de micronúcleos em relação ao grupo não exposto ao benzeno (p<0,01). Frentistas com hábito etílico apresentaram aumento significativo de micronúcleos (p<0,01), quando comparados aos frentistas abstêmios. Verificou-se que 100% dos profissionais entrevistados não fazem uso dos equipamentos de proteção. Conclusão: Constatou-se um aumento na presença de micronúcleos em células esfoliativas de frentistas em comparação ao grupo controle. Esse aumento é ainda maior quando o frentista ingere frequentemente bebidas alcoólicas.
Background: Gas station attendants are at high risk of poisoning due to continuous exposure to fuel fumes. Benzene, present in gasoline, is considered a carcinogen and harmful to the health of gas station attendants. Objective: To investigate genotoxic effects on exfoliated oral mucosa cells in association with occupational exposure among gas station attendants in Santarem, Para, Brazil, and to establish the rate of adherence to personal protective equipment (PPE). Methods: The results of the micronucleus test performed with oral mucosa cells stained by means of the Feulgen and Fast Green methods were compared between 126 exposed gas station attendants distributed across six groups and controls. Results: The frequency of micronuclei was higher among gas station attendants compared to the group not exposed to benzene (p<0.01). The frequency of micronuclei was significantly higher (p<0.01) among the gas station attendants who reported to drink alcohol compared to non-drinkers. None of the participants (0%) used PPE. Conclusion: The frequency of micronuclei in exfoliated oral mucosa cells was higher among gas station attendants compared to controls; frequency was even higher for the gas station attendants who reported to consume alcohol often
ABSTRACT
BACKGROUND: Gas station attendants are at high risk of poisoning due to continuous exposure to fuel fumes. Benzene, present in gasoline, is considered a carcinogen and harmful to the health of gas station attendants. OBJECTIVE: To investigate genotoxic effects on exfoliated oral mucosa cells in association with occupational exposure among gas station attendants in Santarem, Para, Brazil, and to establish the rate of adherence to personal protective equipment (PPE). METHODS: The results of the micronucleus test performed with oral mucosa cells stained by means of the Feulgen and Fast Green methods were compared between 126 exposed gas station attendants distributed across six groups and controls. RESULTS: The frequency of micronuclei was higher among gas station attendants compared to the group not exposed to benzene (p<0.01). The frequency of micronuclei was significantly higher (p<0.01) among the gas station attendants who reported to drink alcohol compared to non-drinkers. None of the participants (0%) used PPE. CONCLUSION: The frequency of micronuclei in exfoliated oral mucosa cells was higher among gas station attendants compared to controls; frequency was even higher for the gas station attendants who reported to consume alcohol often.
INTRODUÇÃO: Profissionais frentistas encontram-se em situação de risco tóxico pela exposição constante aos vapores dos combustíveis. O benzeno, presente na gasolina, é considerado cancerígeno e prejudicial à saúde desses trabalhadores. OBJETIVO: Avaliar os efeitos genotóxicos decorrentes da exposição ocupacional em células esfoliativas da mucosa oral de frentistas do município de Santarém, Pará; e determinar a taxa de adesão ao uso de equipamentos de proteção individual por esses colaboradores. MÉTODOS: Um total de 126 frentistas, distribuídos em 6 grupos contendo indivíduos expostos foram comparados ao grupo controle utilizando a técnica do ensaio de micronúcleos em células da mucosa oral coradas com as técnicas de Feulgen/Fast-green. RESULTADOS: Os frentistas apresentaram maior frequência de micronúcleos em relação ao grupo não exposto ao benzeno (p<0,01). Frentistas com hábito etílico apresentaram aumento significativo de micronúcleos (p<0,01), quando comparados aos frentistas abstêmios. Verificou-se que 100% dos profissionais entrevistados não fazem uso dos equipamentos de proteção. CONCLUSÃO: Constatou-se um aumento na presença de micronúcleos em células esfoliativas de frentistas em comparação ao grupo controle. Esse aumento é ainda maior quando o frentista ingere frequentemente bebidas alcoólicas.
ABSTRACT
The genus Pimelodus LaCépède, 1803 comprises 35 formally recognized species distributed along the major neotropical river basins. Despite conservatism in diploid number with 2n=56, an intense variation of chromosomal morphology (karyotypic formula) has been documented in Pimelodus species. In the present study, we analyzed karyotypes of 20 specimens, identified as Pimelodusblochii Valenciennes, 1840 and collected from the lower courses of the Tapajós, Amazonas and Trombetas Rivers. The karyotypes were characterized by Giemsa conventional staining, C-banding, silver staining (Ag-NOR) and fluorescent in situ hybridization (FISH) with 5S and 18S rDNA probes. The karyotypes showed 2n=56 chromosomes in fish from the Tapajós River. In contrast, fish from the Amazonas and Trombetas Rivers had 2n=58. The nucleolus organizing regions were labeled on the short arm of an acrocentric chromosome as demonstrated by silver staining and FISH. Signals for 18S and 5S rDNA were co-localized on one chromosome pair. Our results demonstrate karyotypic divergence between Tapajós and Amazonas-Trombetas populations of P.blochii, interpreted as supporting the existence of a species complex in this taxon.
