Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros











Intervalo de año de publicación
2.
Rev. bras. entomol ; 56(4): 431-435, Oct.-Dec. 2012. ilus
Artículo en Inglés | LILACS | ID: lil-662675

RESUMEN

Drosophila caxiuana sp. nov., Drosophila subgenus, is described and illustrated. This new species was collected in the Amazonian Biome (Caquajó river, Portel, Pará, Brazil) and is an atypical species to the group due the unusual morphology of the male terminalia.


Drosophila caxiuana sp. nov., subgênero Drosophila, é descrita e ilustrada. Essa nova espécie foi coletada no Bioma Amazônico (Rio Caquajó, Portel, Pará, Brasil) e é uma espécie atípica deste grupo devido à morfologia incomum da terminália masculina.

3.
Evolution ; 63(1): 280-7, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18752606

RESUMEN

The idea of a general independence between the phenotypic plasticity and the mean value of a trait is, presently, a consensus. Here, we use the reaction norm of abdominal pigmentation (number of dark spots) of Drosophila mediopunctata in response to temperature, to test this idea. We raised eight strains, bearing two different chromosomal inversions and with varying mean phenotypic values, under 11 temperatures in a thermal gradient to test for predictions concerning mean phenotypic values, chromosomal inversions, and reaction norms. Our results revealed a strong effect of different phenotypic groups and no effect of different karyotypes on reaction norms. Moreover, we found a significant negative correlation between mean phenotypic value and the curvature of the reaction norms, revealing a high dependency of the reaction norm shape on mean phenotypic value. These results clearly reject the idea of genetic independence between mean value and phenotypic plasticity, and may indicate a pattern of correlation, which may include results from other traits and species, with an importance that has not been fully appreciated.


Asunto(s)
Drosophila/anatomía & histología , Drosophila/genética , Variación Genética , Abdomen/anatomía & histología , Animales , Fenotipo , Pigmentación , Temperatura
5.
Bol Oficina Sanit Panam ; 116(3): 212-6, 1994 Mar.
Artículo en Español | MEDLINE | ID: mdl-7518685

RESUMEN

With the objective of finding reliable, valid, and economic diagnostic tests to identify Chlamydia trachomatis in conjunctival smears, the sensitivity, specificity, and positive and negative predictive values of Lendrum and Giemsa stains were evaluated using direct immunofluorescence as the gold standard. In addition, inter- and intraobserver reproducibility were estimated through the use of two independent observers, who were blinded to the results during their readings. The prevalence of ocular chlamydiosis in the study area was around 50%. In all, 103 persons (206 eyes) were studied. Three smears from each eye were taken for each subject. The kappa statistic was used to estimate the reproducibility of the stains. Interobserver reproducibility was null, and intraobserver reproducibility ranged between 0.35 and 0.79. The sensitivity of the Giemsa stain was a bit higher than that of the Lendrum stain (28% and 22%, respectively), and the specificity was similar (82% and 85%, respectively). Based on these results, the ability of both stains to detect positive cases was judged to be low, as was their reliability. The Lendrum and Giemsa stains are not adequate tests for the diagnosis of ocular chlamydiosis. For this purpose the use of direct immunofluorescence is recommended.


Asunto(s)
Colorantes Azulados , Chlamydia trachomatis/aislamiento & purificación , Conjuntivitis de Inclusión/microbiología , Coloración y Etiquetado , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Conjuntivitis de Inclusión/diagnóstico , Errores Diagnósticos , Técnica del Anticuerpo Fluorescente , Humanos , Cuerpos de Inclusión/ultraestructura , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados
6.
J Immunol ; 133(3): 1185-9, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6235283

RESUMEN

In previous studies, it was shown that there is polymorphism in the mitogenic effect of mouse IgG1 monoclonal antibodies against the T3 antigen of human T cells. This polymorphism implies that IgG1 anti-T3 antibodies are not mitogenic for T cells from 30% of healthy individuals. The present results demonstrate that this polymorphism is caused by polymorphism of an Fc receptor for mouse IgG1, present on human monocytes. The Fc receptor for murine IgG1 could be detected by a newly developed rosetting assay on monocytes from all individuals responsive to the mitogenic effect of IgG1 anti-T3 antibodies. This Fc receptor was not detectable on monocytes from those individuals exhibiting no mitogenic responses to IgG1 anti-T3 monoclonal antibodies. Cross-linking of T3 antigens appears to be essential for antibody-induced mitosis of T cells, because mononuclear cells that did not proliferate in response to WT 31 (an IgG1 antibody against T3 antigen) showed a proliferative response to Sepharose beads coated with WT 31. The Fc receptor--if functionally present--may be involved in the cross-linking of T3 antigens through anti-T3 antibodies. Further evidence for the involvement of this Fc receptor in antibody-induced T cell proliferation was provided by inhibition studies. Immune complexes containing IgG1 antibodies were able to inhibit the proliferative response to IgG1 anti-T3 antibodies. This inhibition by immune complexes appears to be mediated through the monocyte Fc receptor for mouse IgG1. These findings are important for the interpretation of previously described inhibitory effects of anti-T cell monoclonal antibodies on T cell proliferation, and show that such inhibitory effects may be monocyte-mediated (via immune complexes) rather than caused by a direct involvement of the respective T cell antigens in T cell mitosis. The Fc receptor for mouse IgG1 plays a role in antibody-induced T cell proliferation. Its polymorphism may have important implications for the therapeutic use of IgG1 monoclonal antibodies.


Asunto(s)
Anticuerpos Monoclonales/fisiología , Activación de Linfocitos , Monocitos/metabolismo , Polimorfismo Genético , Receptores Fc/genética , Linfocitos T/inmunología , Animales , Sitios de Unión de Anticuerpos , Unión Competitiva , Humanos , Inmunoglobulina G/metabolismo , Ratones , Mitógenos/farmacología , Receptores Fc/inmunología , Receptores de IgG , Formación de Roseta
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA