Résumé
Trianthema portulacastrum is a noxious weed which spreads rapidly in the field. Pathogen Alternaria alternata was observed on this host for three years continuously i.e. 1997 to 1999. The incidence of the pathogen depended on rainfall and temperature.
Sujets)
Agriculture , Alternaria/pathogénicité , Incidence , Mycoses/anatomopathologie , Lutte contre les nuisibles , Plantes , Pluie , Récidive , TempératureRésumé
Plasma membrane of Leishmania donovani promastigotes was isolated by disrupting the cells in Dounce homogenizer and found to be having two fractions M1 and M2. Chemical analysis of the two membrane fractions revealed that M1 had less RNA content and high sterol-phospholipid molar ratio than M2. M1 was also rich in membrane marker enzymes, e.g., 5' nucleotidase and acid phosphatase. Glucose-6-phosphatase, the marker enzyme of endoplasmic reticulum was higher in M2 fraction. The electron micrograph also revealed the presence of plasma membrane vesicles in M1 fraction.
Sujets)
Animaux , Membrane cellulaire/composition chimique , Leishmania donovani/génétique , Microscopie électronique , ARN/analyseRésumé
Ureastibamine, a pentavalent antimonial, reduced the parasitic load in the 60-day model of infection of L. donovani in hamsters. It also inhibited the in vivo multiplication of I donovani amastigotes in hamster peritoneal macrophages. No inhibition in either promastigote multiplication or amastigotes transformation was noted with filtrate obtained after incubation of the drugs for 72 h in the macrophage culture. Incubation of macrophages with ureastibamine revealed an impairment in the uptake of deoxyglucose. The effect of ureastibamine was compared with that of another pentavalent antimonial, sodium stibogluconate. It is suggested that impairment of macrophage membrane may contribute towards the adverse effect of these drugs against the intracellular parasite.