25 We present the results of the first detailed study of the antiproliferative and 26 ultrastructural effect of amiodarone on Trypanosoma cruzi, the causative agent of 27 Chagas' disease. Moreover, we report the effects of this compound on the recovery of 28 F-actin fibrils, connexin43 and contractility in T. cruzi infected cardiac myocytes. 29 Amiodarone is the most prescribed class III antiar...

Visceral leishmaniasis is a vector-borne disease caused by an obligate intracellular protozoan parasite Leishmania donovani. The molecular mechanism involved in internalization of Leishmania is poorly understood. The entry of Leishmania involves interaction with the plasma membrane of host cells. We have previously demonstrated the requirement of host membrane cholesterol in the binding and int...

Specific glycosphingolipid antigens of Leishmania (L.) amazonensis amastigotes reactive with the monoclonal antibodies (MoAbs) ST-3, ST-4 and ST-5 were isolated, and their structure was partially elucidated by negative ion fast atom bombardment mass spectrometry. The glycan moieties of five antigens presented linear sequences of hexoses and N-acetylhexosamines ranging from four to six sugar res...

Reporter genes have proved to be an excellent tool for studying disease progression. Recently, the green fluorescent protein (GFP) ability to quantitatively monitor gene expression has been demonstrated in different organisms. This report describes the use of Leishmania tarentolae (L. tarentolae) expression system (LEXSY) for high and stable levels of GFP production in different Leishmania spec...

Attachment of the prenyl groups farnesyl and geranylgeranyl to specific eukaryotic cell proteins by protein prenyltransferases is required for the functioning of a number of cellular processes including signal transduction. In this study it was found that previously reported inhibitors of mammalian protein farnesyltransferase (PFT) [those that mimic the substrate farnesyl pyrophosphate and thos...

In spite of the growing knowledge obtained about immune control of Trypanosoma cruzi infection, the mechanisms responsible for the variable clinico-pathological expression of Chagas disease remain unknown. In a twist from previous concepts, recent studies indicated that tissue parasitism is a pre-requisite for the development of chronic myocarditis. This fundamental concept, together with the r...

A natural case of co-infection by Leishmania and Trypanosoma is reported in a dog (Canis familiaris) in south- western state of Mato Grosso do Sul, Brazil. Both amastigote and trypomastigote forms were observed after Giemsa staining of cytological preparations of the dog's bone marrow aspirate. No parasite was detected using medium culture inoculation of the sample. DNA obtained from the bone m...

The acute phase of Trypanosoma cruzi infection is associated with a strong inflammatory reaction in the heart characterised by a massive infiltration of immune cells that is dependent on the T. cruzi strain and the host response. 15d-PGJ(2) belongs to a new class of anti-inflammatory compounds with possible clinical applications. We evaluated the effects of 15d-PGJ(2) administered during the ac...

Leishmania (Leishmania) amazonensis exhibits peculiarities in its interactions with hosts. Because amastigotes are the primary form associated with the progression of infection, we studied the effect of insulin-like growth factor (IGF)-I on interactions between L. (L.) amazonensis amastigotes and macrophages. Upon stimulation of infected macrophages with IGF-I, we observed decreased nitric oxid...

Widespread antimonial resistance in anthroponotic visceral leishmaniasis (VL) makes it critical to monitor the susceptibility of prevailing field isolates to upcoming antileishmanials in order to frame the right treatment policies to protect these drugs against development of resistance. We aimed to generate the baseline data on natural in vitro susceptibility to paromomycin and sitamaquine in ...