RESUMO
We report the application of a method which combines digestion with pancreatin and neutral detergent treatment in the analytical study of dietary fiber from cassava. The use of pancreatin previous to the detergent extraction enabled rapid filtration, thus giving more reproducible results for neutral detergent fiber (NDF). Acid detergent fiber (ADF), hemicellulose, lignin and pectin were also determined. The values obtained for NDF (4.65%) and pectin (1.17%) are very important, considering their role in the digestive process.
Assuntos
Fibras na Dieta/análise , Manihot/química , Celulose/análise , Humanos , Lignina/análise , Pectinas/análise , Polissacarídeos/análise , Amido/análiseRESUMO
Phagocytosis of Leishmania is an early event in the capacity of human polymorphonuclear cells to limit the spread of this infectious agent. We compared two methods to assess the phagocytosis of Leishmania by PMN cells; the first using histochemical staining with Wright or Giemsa, and the second using the immunoperoxidase technique with anti-Leishmania monoclonal antibodies. The quantitative results obtained with either of the cytochemical methods were comparable with the immunoperoxidase technique, but the latter offered the advantage of an easier identification of the intracellular parasites. This improvement greatly reduced the time required to quantify phagocytosis compared to the conventional staining techniques.
Assuntos
Anticorpos Monoclonais , Leishmania/imunologia , Neutrófilos/imunologia , Fagocitose/imunologia , Adulto , Animais , Anticorpos Antiprotozoários , Feminino , Humanos , Técnicas Imunoenzimáticas , Técnicas In Vitro , Leishmania braziliensis/imunologia , Leishmania mexicana/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Masculino , Neutrófilos/parasitologia , Coloração e Rotulagem/métodosRESUMO
Amastigotes from Leishmania braziliensis and L. mexicana were isolated from cutaneous lesions in infected animals using the plant lectin Concanavalin A as a specific agglutination agent. Amastigotes were collected in preparations of up to 95% purity as determined by cell count. The parasites obtained by this method showed no apparent loss of viability as measured by growth rated and DNA replication, or pathogenicity as measured by routine passages in hamsters or mice.
Assuntos
Leishmania/isolamento & purificação , Leishmaniose/parasitologia , Técnicas Microbiológicas , Pele/parasitologia , Aglutinação , Animais , Concanavalina A/imunologia , Cricetinae , DNA/biossíntese , Humanos , Leishmania/imunologia , Leishmania/fisiologia , CamundongosRESUMO
The infective stages of Leishmania braziliensis, amastigotes and promastigotes subcultured a limited number of times, were agglutinated by Ricinus communis agglutinin and Concanavalin A. These results suggest that terminal ligands similar or identical with alpha-D mannose, alpha-D glucose (specific receptors for Con A), and alpha-D galactose (specific receptor for RCA) are present in the surface membrane of L. braziliensis. Noninfective promastigotes from the same stock, but subcultured approximately 500 times, were not agglutinated by RCA suggesting either the absence of the alpha-D galactose groups in the surface membrane or their presence in a very reduced number. Agglutination with soybean agglutinin, wheat germ agglutinin, or phytohemagglutinin P was not observed in any of the L. braziliensis forms tested. The difference in polysaccharide residues on the surface membrane of L. braziliensis may be related to the different pathogenic properties of the cell.