Aspectos patológicos del músculo esquelético debido a la infección experimental por trypanosoma cruzi / Pathological aspects of skeletal muscle in experimental trypanosoma cruzi infection

En este estudio se muestran los signos clínicos desarrollados por ratones durante la fase aguda de la infección producida por tres cepas de trypanosoma cruzi. Los ratones infectados con la cepa Dm74 sufrieron alteración de la mobilidad de los miembros posteriores y murieron durante la fase aguda de la infección. El análisis histológico del músculo esquelético mostró infiltrado inflamatorio de leucocitos mononucleares y polimorfonucleares, fibroblastos, eritrocitos libres y depósitos de IgG en el espacio intersticial del Gastrocnemius (G). La desintegración de las microfibrillas y cambios en la microvasculatura, fibras nerviosas y en la unión neuromuscular del G fueron también observados. Estos resultados indican que la infección aguda producida por T. cruzi causa daño progresivo en la fibra muscular esquelética y alteración de la actividad motora

Epidemiology of cutaneous leishmaniasis in Merida, Venezuela. III. Altitudinal distribution, age structure, natural infection and feeding behaviour of sandflies and their relation to the risk of transmission.

An entomological survey revealed that the distribution of the Lutzomyia species in Merida, Venezuela, varies with altitude. Of the 21 species encountered, 12 (57%) are known to be anthropophilic. The significance of the predominant man-biting species at any altitude is discussed in terms of the risk of transmission of cutaneous leishmaniasis. The general parous rate (and perhaps the ability of a female sandfly to survive oviposition and transmit Leishmania parasites during a second or subsequent bloodmeal) was found to be related to rainfall and altitude. The finding of Leishmania infections in wild-caught parous females of anthropophilic species indicates the high risk of acquiring leishmaniasis in the study area. Observations on the feeding habits of the sandflies indicate that some species are opportunistic feeders, attracted to a variety of hosts, including man.

Antimony determination in tissues and serum of hamsters infected with Leishmania garnhami and treated with meglumine antimoniate.

Hamsters were experimentally infected with Leishmania garnhami and then treated for 10 days with N-methyl-glucamine antimoniate (Glucantime); 60 mg/kg/day by intramuscular (im) or intralesional (il) routes. Hydride generation-atomic absorption spectroscopy was used to determine the concentrations of SbIII and SbV in the blood serum and total Sb in the tissues of the hamsters from 1 to 30 days after initiation of the treatment. Serum concentrations of SbIII and SbV were always similar. Total Sb concentrations were significantly higher in the relatively parasite-rich spleen and lesion than in any other tissue, whether treatment had been given im or il. Reduction of SbV to SbIII is probably associated with decreasing size and healing of the leishmanial ulcers. Tissue Sb kinetics is related to Leishmania behaviour and attention is drawn to the use of antimonial pentavalent compounds for diseases, other than leishmaniasis, that can affect the heart, liver and/or spleen, such as Chagas disease.