α-Gal immunization positively impacts Trypanosoma cruzi colonization of heart tissue in a mouse model

Chagas disease, caused by the parasite Trypanosoma cruzi, is considered endemic in more than 20 countries but lacks both an approved vaccine and limited treatment for its chronic stage. Chronic infection is most harmful to human health because of long-term parasitic infection of the heart. Here we show that immunization with a virus-like particle vaccine displaying a high density of the immunogenic α-Gal trisaccharide (Qβ-αGal) induced several beneficial effects concerning acute and chronic T. cruzi infection in α1,3-galactosyltransferase knockout mice. Approximately 60% of these animals were protected from initial infection with high parasite loads. Vaccinated animals also produced high anti-αGal IgG antibody titers, improved IFN-γ and IL-12 cytokine production, and controlled parasitemia in the acute phase at 8 days post-infection (dpi) for the Y strain and 22 dpi for the Colombian strain. In the chronic stage of infection (36 and 190 dpi, respectively), all of the vaccinated group survived, showing significantly decreased heart inflammation and clearance of amastigote nests from the heart tissue.

Leishmania amazonensis: early proteinase activities during promastigote-amastigote differentiation in vitro

Leishmania proteinase activity is known as parasite differentiation marker, and has been considered relevant for leishmanial survival and virulence. These properties suggest that Leishmania proteinases can be promising targets for development of anti-leishmania drugs. Here, we analyze the activities of four proteinases during the early phase of the Leishmania amazonensis promastigotes differentiation into amastigotes induced by heat shock. We have examined activities of cysteine-, metallo-, serine-, and aspartic-proteinase by hydrolysis of specific chromogenic substrates at pH 5.0 and at the optimal pH for each enzyme. Our results show that metallo-, serine-, and aspartic-proteinases activities were down-regulated during the shock-induced transformation of promastigotes into amastigotes. In contrast, cysteine-proteinase activity increased concomitantly with the promastigote differentiation. Immunocytochemical localization using two anti-cysteine-proteinase monospecific rabbit antibodies detected the enzyme in several cell compartments of both parasite stages. Our results show different proteinase activity modulation and expression during the early phases of the shock-induced parasite transformation.

Characterization of the species- and stage-specificity of two monoclonal antibodies against Leishmania amazonensis

Leishmania metacyclogenesis is associated with changes in morphology, gene expression, and structural alterations of the lipophosphoglycan (LPG), the promastigote most abundant surface glycolipid. Purification of metacyclics is accomplished using lectins or monoclonal antibodies (MAbs) that exploit stage-specific differences in the LPG. Besides, LPG displays extensive interspecies polymorphisms and is synthesized by promastigotes of all species investigated to date. In this work we studied the species- and stage-specificity of two MAbs (3A1-La and LuCa-D5) used to purify metacyclics of Leishmania amazonensis. Their ability to recognize different members of the Trypanosomatidae family was tested by direct agglutination, indirect immunofluorescence, and dot-blot analysis of LPG. We found that both MAbs were highly selective for L. amazonensis: 3A1-La recognized only promastigotes and LuCa-D5 labeled amastigote and promastigote stages of this species. These MAbs might be useful for Leishmania typing.

[Brazilian Nursing Association: 70 years of struggle for life]

This work is about the Brazilian Nursing Association (ABEn), its origin, its expansion and projection based on its philosophy and highlighting its achievements from its origin in 1926 until today when its 70th anniversary is being celebrated. This work aims at reporting this institution history and narrating the support provided so that nursing may contribute decisively to the construction of a body of profession knowledge itself, the legal definition of professional practice, teaching regulamentation through its commissions. Methodology has been composed of bibliographic research and interviews with active professionals. It has been concluded that ABEn is stronger and stronger and aware of the way on how to achieve many other goals which will bear great conquests which will contribute for granting nursing power and space as a profession set to the human, therefore, to a better life, with more love, peace and social justice.

[Evaluation of direct agglutination tests in the detection of Leishmania (Viannia) braziliensis in possible reservoirs of cutaneous American leishmaniasis in the state of Ceará]

In order to evaluate the aplicability of the Direct Agglutination Test (DAT) as a method of detection of the natural canine infection for Leishmania (Viannia) braziliensis, it was realized a study involving the serum of naive dogs from Serra de Baturite, Ceara State, an endemic area of cutaneous leishmaniasis, and others from Curitiba, Parana State, a non endemic area. The results indicate the possibility of using this sorologic test to the epidemiologic research of the infection in the reservoir host; in this case, the dog.

Cryptosporidial and microsporidial infections in human immunodeficiency virus-infected patients in northeastern Brazil

To determine the frequency of the parasitic pathogens in human immunodeficiency virus (HIV)-infected patients in a developing world setting, 295 stool specimens were examined from 166 HIV-positive patients (49% with AIDS) at São José Hospital, Fortaleza, Brazil, from September 1990 to March 1992. Significantly more patients with diarrhea (85%) than without (66%) had AIDS or AIDS-related complex (ARC) (P < .005). Of the potential parasitic causes of diarrhea, only Cryptosporidium parvum and microsporidia were significantly associated with diarrheal disease. Infections with C. parvum, but not microsporidia, were associated with the rainy season (P < .005). Thus, C. parvum and microsporidia are the most common intestinal parasites associated with diarrhea in an HIV-infected population in Brazil and are associated with advanced HIV disease. The association of C. parvum infections with the rainy season suggests that contaminated water may be important in its transmission; however, the source of human microsporidia requires further investigation.