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1.
Genet Mol Res ; 11(4): 4198-203, 2012 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-23315804

RESUMO

The Anopheles albitasis complex includes 6 species, and 3 are considered as malaria vectors in Brazil. Twenty-five polymorphic microsatellite DNA loci were isolated and characterized in 24-36 individuals from the neighborhood of Puraquequara, Manaus, Amazonas State, Brazil. The number of estimated alleles ranged from 2 to 10, the observed heterozygosity ranged from 0.182 to 0.897, and the expected heterozygosity ranged from 0.260 to 0.854. Eleven loci showed significant deviation from Hardy-Weinberg equilibrium. Eleven loci were cross-amplified successfully in 5 Anopheles species. These microsatellite loci will be useful in studies investigating population structure and evolutionary genetics in A. albitarsis sensu lato and other A. albitarsis complex species.


Assuntos
Anopheles/genética , Genes de Insetos , Insetos Vetores/genética , Repetições de Microssatélites , Animais , Loci Gênicos , Genótipo , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Especificidade da Espécie
3.
Homeopathy ; 93(3): 132-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15287432

RESUMO

One strand of research on the scientific basis of homeopathy is based on inversion effects of dilutions and the biophysical properties of information transfer. A model developed by Endler, was the basis for the study of the influence of high-diluted solution (1:1026 part by weight) of thyroid glands on the rate of metamorphosis of the frog Rana catesbeiana from the no legged to four-legged stage. The glands were obtained from tadpoles and prepared according by (dilution and succussion). Similar pure hydroalcoholic solution (unsuccussed) was used as control. In order to identify significant differences in the frequencies of four-legged tadpoles, in homeopathic and control group, we used a chi-square goodness-of-fit test (P<0.01) and the cumulative risk for metamorphosis by Cox's Proportional Hazards model (P<0.05). The number of animals that reached the four-legged stage is generally smaller in the treated group, than in the hydroalcoholic control group. It was postulated that thyroid hormones transmitted information' specific to the molecules used to prepare the solution, even though the molarity was beyond Avogadro's number.


Assuntos
Homeopatia/métodos , Metamorfose Biológica/efeitos dos fármacos , Rana catesbeiana , Tiroxina/farmacologia , Animais , Distribuição de Qui-Quadrado , Relação Dose-Resposta a Droga , Atividade Motora/efeitos dos fármacos , Distribuição Aleatória , Tiroxina/administração & dosagem , Fatores de Tempo
4.
Environ Res ; 92(3): 191-6, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12804515

RESUMO

In this study, we explored the role of chronic exposure to urban air pollution in causing DNA damage (micronuclei frequency in peripheral erythrocytes) in rodents in vivo. Mice (n=20) were exposed to the urban atmosphere of São Paulo for 120 days (February to June 1999) and compared to animals (n=20) maintained in the countryside (Atibaia) for the same period. Daily levels of inhalable particles (PM10), CO, NO(2), and SO(2), were available for São Paulo. Occasional measurements of CO and O(3) were made in Atibaia, showing negligible levels of pollution in the area. The frequency of micronuclei (repeated-measures ANOVA) increased with aging, the highest values obtained for the 90th day of experiment (P<0.001). The exposure to urban air pollution elicited a significant (P=0.016) increase of micronuclei frequency, with no significant interaction with time of study. Associations (Spearman's correlation) between pollution levels of the week that precede blood sampling and micronuclei counts were observed in São Paulo. The associations between micronuclei counts and air pollution were particularly strong for pollutants associated with automotive emissions, such as CO (P=0.037), NO(2) (P<0.001), and PM10 (P<0.001). Our results support the concept that urban levels of air pollution may cause somatic mutations.


Assuntos
Poluentes Atmosféricos/toxicidade , Eritrócitos/efeitos dos fármacos , Saúde da População Urbana , Administração por Inalação , Animais , Brasil , Relação Dose-Resposta a Droga , Eritrócitos/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/ultraestrutura , Testes para Micronúcleos , Emissões de Veículos/toxicidade
6.
Braz. j. med. biol. res ; 31(3): 421-30, Mar. 1998. tab, graf
Artigo em Inglês | LILACS | ID: lil-212279

RESUMO

In the present study, using noise-free simulated signals, we performed a comparative examination of several preprocessing techniques that are used to transform the cardiac event series in a regularly sampled time series, appropriate for spectral analysis of heart rhythm variability (HRV). First, a group of noise-free simulated point event series, which represents a time series of heartbeats, was generated by an integral pulse frequency modulation model. In order to evaluate the performance of the preprocessing methods, the differences between the spectra of the preprocessed simulated signals and the true spectrum (spectrum of the model input modulating signals) were surveyed by visual analysis and by contrasting merit indices. It is desired that estimated spectra match the true spectrum as close as possible, showing a minimum of harmonic components and other artifacts. The merit indices proposed to quantify these mismatches were the leakage rate, defined as a measure of leakage components (located outside some narrow windows centered at frequencies of model input modulating signals) with respect to the whole spectral components, and the numbers of leakage components with amplitudes greater than 1 percent, 5 percent and 10 percent of the total spectral components. Our data, obtained from a noise-free simulation, indicate that the utilization of heart rate values instead of heart period values in the derivation of signals representative of heart rhythm results in more accurate spectra. Furthermore, our data support the efficiency of the widely used preprocessing technique based on the convolution of inverse interval function values with a rectangular window, and suggest the preprocessing technique based on a cubic polynomial interpolation of inverse interval function values and succeeding spectral analysis as another efficient and fast method for the analysis of HRV signals.


Assuntos
Testes de Função Cardíaca/métodos , Frequência Cardíaca , Processamento de Sinais Assistido por Computador , Estimulação Acústica , Análise Espectral
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