RESUMO
The production of micronuclei in rat bone marrow cells by the synthetic pyrethroid insecticide meothrin was investigated. Three different doses of meothrin were orally administered to rats for 14 consecutive days. All tested doses of meothrin increased the frequency of micronucleated polychromatic erythrocytes but the increase was statistically significant only at the two highest doses. Meothrin also affected the rate of bone marrow cell proliferation, as determined by changes in the ratio of polychromatic erythrocytes to normochromatic erythrocytes.
Assuntos
Células da Medula Óssea/efeitos dos fármacos , Inseticidas/farmacologia , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Piretrinas/farmacologia , Administração Oral , Animais , Células da Medula Óssea/citologia , Divisão Celular/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/genética , Testes para Micronúcleos , Nitrilas , Ratos , Ratos Sprague-DawleyRESUMO
The cosegregation of ten coding loci has been investigated, in a panel of 37 somatic cell hybrids resulting from the fusion of a hamster cell line and river buffalo lymphocytes, by use of Southern hybridization technique. Five syntenic groups, TCRB-PGY3, ASS-ABL, FUCA1P-CRYG, MBP-YES1, and CGN1-ACTA1, previously assigned to cattle as U13, U16, U17, U28, and U29 respectively, were also found to be syntenic in buffalo. Based on the extensive syntenic conservation and banding homology between cattle and river buffalo, comparative mapping predicts the localization of these syntenic groups on river buffalo Chromosomes (Chrs) :BBU7, BBU12, BBU2q, BBU22, and BBU4q respectively as they have been previously localized on cattle Chrs BTA4, BTA11, BTA2, BTA24 & BTA28.
Assuntos
Búfalos/genética , Mapeamento Cromossômico , Ligação Genética , Animais , Bovinos , Linhagem Celular , Bandeamento Cromossômico , Cricetinae , Cricetulus , Humanos , Células Híbridas , Linfócitos , Mapeamento por RestriçãoRESUMO
Male Swiss mice are tested under uniform 50-Hz electric field intensities of 100, 170, 220, and 290 kV/m. These values on the basis of equal induced current density are equivalent to the case of a human exposed to field intensities of nearly 8, 14, 18, and 24 kV/m, respectively. The latter values may be found beneath or in the vicinity of extra-high-voltage power lines whose voltages range from 220 to 765 kV. The cytogenetic effect of extremely low-frequency (ELF) electric fields, as expressed by micronuclei formation, is assessed. Mice are exposed for 24 hr, and samples are taken 48, 72, and 96 hr from the beginning of exposure. Sham-exposed mice served as controls. The number of micronucleated polychromatic erythrocytes (PCE) in exposed animals are significantly higher than those of the control. The increase in micronucleated PCE was significantly dose dependent at all times. Samples taken 96 hr after exposure show a decrease in percentages of micronucleated PCE, which may be taken as an indication of recovery.
