Hallmarks of liver lesions in pigs naturally infected by hepatitis E virus genotype 3 / Perfil das lesões histopatológicas hepáticas em suínos infectados naturalmente pelo genótipo 3 do vírus da hepatite E

Histopathological evaluation of liver from 33 pigs slaughtered for human consumption in Amazon region, previously tested by serology and molecular techniques for hepatitis E virus infection (HEV), was analysed in three groups: Group 1, negative for both HEV-RNA and anti-HEV IgG (n=10); Group 2, positive for HEV-RNA (n=13); Group 3, positive for anti-HEV IgG (n=10). Group 2 showed a significant difference among the groups for liver lesions such as lobular activity (P=0.007), periportal interface hepatitis (P=0.004), portal inflammation (P=0.028) hepatitis with lobular, portal and periportal interface activity (P=0.001). HEV detection by immunohistochemistry was performed and 3 of 6 samples of group 2 were positive. Pigs naturally infected by HEV genotype 3 present microscopic necroinflammatory liver lesions similar to HEV in humans. Liver histopathology showed be important in the diagnosis of active asymptomatic HEV infection in pigs slaughtered for human consumption because hepatic liver lesions may present distinct profiles according to molecular and serological diagnosis and in this sense, histopathology and immunohistochemistry may be an important complementary diagnostic tool.(AU)

A avaliação histopatológica hepática de 33 suínos abatidos para consumo humano na região amazônica, previamente testados para infecção pelo vírus da hepatite E (HEV) por sorologia e técnicas moleculares, foi realizada em três grupos: Grupo 1, animais negativos para HEV-RNA e anti-HEV IgG (n=10); Grupo 2, positivos para HEV-RNA (n=13); e Grupo 3, positivos para anti-HEV IgG (n=10). O grupo 2 apresentou diferenças estatísticas significantes entre os grupos em relação à presença de atividade lobular (P=0,007), hepatite periportal de interface (P=0,004), inflamação portal (P= 0.028) e atividade lobular acompanhada por inflamação portal e periportal de interface (P=0,001). A detecção imunohistoquímica do HEV foi realizada e três de seis amostras do Grupo 2 foram positivas. Suínos naturalmente infectados pelo genótipo 3 do HEV apresentam lesões necroinflamatórias no fígado similares a lesão em humanos. A histopatologia hepática demonstrou ser importante no diagnóstico de infecção ativa e assintomática por HEV em suínos abatidos para consumo humano, pois as lesões no fígado apresentaram perfis diferenciados de acordo com o diagnóstico sorológico e molecular da infecção e, neste sentido, a histopatologia e imunohistoquímica podem representar importantes ferramentas complementares de diagnóstico.(AU)

Specific activation of CD4- CD8- double-negative T cells by Trypanosoma cruzi-derived glycolipids induces a proinflammatory profile associated with cardiomyopathy in Chagas patients.

Cardiomyopathy is the most severe outcome of Chagas disease, causing more than 12 000 deaths/year. Immune cells participate in cardiomyopathy development either by direct tissue destruction, or by driving inflammation. We have shown that CD4- CD8- [double-negative (DN)] T cells are major sources of inflammatory and anti-inflammatory cytokines, associated with the cardiac (CARD) and indeterminate (IND) forms of Chagas disease, respectively. Here, we sought to identify Trypanosoma cruzi-derived components that lead to activation of DN T cells in Chagas patients. Glycolipid (GCL), lipid (LIP) and protein-enriched (PRO) fractions derived from trypomastigote forms of T. cruzi were utilized to stimulate cells from IND and CARD patients to determine DN T cell activation by evaluating CD69 and cytokine expression. We observed that GCL, but not LIP or PRO fractions, induced higher activation of DN T cells, especially T cell receptor (TCR)-γδ DN T, from IND and CARD. GCL led to an increase in tumour necrosis factor (TNF) and interleukin (IL)-10 expression by TCR-γδ DN T cells from IND, while inducing IFN-γ expression by TCR-γδ DN T cells from CARD. This led to an increase in the ratio IFN-γ/IL-10 in TCR-γδ DN T cells from CARD, favouring an inflammatory profile. These results identify GCL as the major T. cruzi component responsible for activation of DN T cells in chronic Chagas disease, associated predominantly with an inflammatory profile in CARD, but not IND. These findings may have implications for designing new strategies of control or prevention of Chagas disease cardiomyopathy by modulating the response to GCL.

Impact of nutritional recovery with linear growth on the concentrations of adipokines in undernourished children living in Brazilian slums.

Undernutrition in early life has been reported to be closely associated with the development of non-communicable diseases in adulthood. Adequate treatment is important for reversing these effects. In the present study, we investigated the effects of undernutrition and anthropometric recovery on the weights and heights of children in relation to the concentrations of leptin, adiponectin and plasminogen activator inhibitor-1 (PAI-1). A total of 119 children (aged 6-16 years) from the slums of São Paulo were selected according to their nutritional status and divided into three groups as follows: control (healthy without intervention, n 38) with a height-for-age Z score (HAZ) and a BMI-for-age Z score (BAZ) > -1·6; undernourished (HAZ and/or BAZ < -1·6, n 54); recovered from undernutrition (after treatment in a rehabilitation centre; HAZ and BAZ > -1·6, n 27). Blood samples were collected to determine insulin, glucose, leptin, adiponectin and PAI-1 concentrations. Leptin concentrations in the undernourished group were lower than those in the control and recovered groups (mean 0·92 (95% CI 0·67, 1·25), 2·03 (95% CI 1·46, 2·82) and 1·66 (95% CI 1·15, 2·44) ng/ml, P=0·003), which had similar leptin concentrations. There were no differences in adiponectin and PAI-1 concentrations among the groups. A positive correlation between waist circumference and leptin concentrations was observed in all the girls and boys of the control group (control: r 0·729, P<0·01; undernourished: r 0·490, P<0·05; and recovered: r 0·829, P<0·01; r 0·673, P<0·05). Stronger correlations between leptin and insulin concentrations were observed in the recovered group. The results of the present study indicate that normal leptin concentrations are found when normal height and weight are achieved.

Mitochondrial and nuclear sequence polymorphisms reveal geographic structuring in Amazonian populations of Echinococcus vogeli (Cestoda: Taeniidae).

To date, nothing is known about the genetic diversity of the Echinococcus neotropical species, Echinococcus vogeli and Echinococcus oligarthrus. Here we used mitochondrial and nuclear DNA sequence polymorphisms to uncover the genetic structure, transmission and history of E. vogeli in the Brazilian Amazon, based on a sample of 38 isolates obtained from human and wild animal hosts. We confirm that the parasite is partially synanthropic and show that its populations are diverse. Furthermore, significant geographical structuring is found, with western and eastern populations being genetically divergent.

Hereditary spherocytosis in zebrafish riesling illustrates evolution of erythroid beta-spectrin structure, and function in red cell morphogenesis and membrane stability.

Spectrins are key cytoskeleton proteins with roles in membrane integrity, cell morphology, organelle transport and cell polarity of varied cell types during development. Defects in erythroid spectrins in humans result in congenital hemolytic anemias with altered red cell morphology. Although well characterized in mammals and invertebrates, analysis of the structure and function of non-mammalian vertebrate spectrins has been lacking. The zebrafish riesling (ris) suffers from profound anemia, where the developing red cells fail to assume terminally differentiated erythroid morphology. Using comparative genomics, erythroid beta-spectrin (sptb) was identified as the gene mutated in ris. Zebrafish Sptb shares 62.3% overall identity with the human ortholog and phylogenetic comparisons suggest intragenic duplication and divergence during evolution. Unlike the human and murine orthologs, the pleckstrin homology domain of zebrafish Sptb is not removed in red cells by alternative splicing. In addition, apoptosis and abnormal microtubule marginal band aggregation contribute to hemolysis of mutant erythrocytes, which are features not present in mammalian red cells with sptb defects. This study presents the first genetic characterization of a non-mammalian vertebrate sptb and demonstrates novel features of red cell hemolysis in non-mammalian red cells. Further, we propose that the distinct mammalian erythroid morphology may have evolved from specific modifications of Sptb structure and function.

Diagnóstico das condiçoes de saúde de uma comunidade garimpeira na regiäo do Rio Tapajós, Itaituba, Pará, Brasil, 1992 / Diagnosis of health conditions in a pan-mining community in the Tapajós river basin, Itaituba, Pará, Brazil, 1992

O objetivo foi conhecer as condiçoes de vida e de saúde de uma comunidade garimpeira e, particularmente, a superposiçäo da contaminaçäo mercurial com outros agravos. Foi realizada no garimpo do Igarapé do Rato, na bacia hidrográfica do rio Tapajós, Itaituba-Pará. A populaçäo abrangeu 223 indivíduos aos quais foi aplicado um questionário epidemiológico, e feito atendimento médico e coleta de espécimes biológicos. Na coproscopia, 96,1 por cento indivíduos estavam parasitados e 66,4 por cento anêmicos. A prevalência para a o vírus da hepatite B ficou em 85 por cento; 11 (6 por cento) em portadores do vírus. Dentre os pacientes investigados para malária, 35 por cento (65) estavam com a doença e desses 52,3 por cento (34) eram pacientes assintomáticos. A prevalência para sífilis foi de 41,6 por cento. As dosagens de mercúrio em urina de 173 indivíduos revelaram 16 (9,2 por cento) pacientes com dosagens maiores do que 10ug/l e até 19 ug/l, enquanto que 9 pacientes (5,2 por cento) do total investigado revelaram teores acima de 20 ug/l. O estudo revela indivíduos com superposiçäo de agravos, sem diagnóstico adequado por falta de atendimento médico, praticando a automedicaçäo, e vivendo a ameaça de intoxicaçäo por mercúrio. Oferece uma visäo geral das condiçoes de saúde encontradas na comunidade garimpeira estudada e atinge a finalidade de por em evidência a multicausalidade encontrada quando se precisa avaliar as condiçoes de saúde na regiäo amazônica, e que deve ser levada em consideraçäo por ocasiäo do atendimento clínico e da administraçäo terapêutica.