Moradores de áreas rurais de municípios mineiros endêmicos para a doença de Chagas: ideias e concepções sobre a doença, os vetores e os serviços de saúde / Residents of rural areas in municipalities of Minas Gerais endemic for Chagas disease: their ideas and conceptions about the disease, vector, and health services

Resumo Introdução A vigilância da doença de Chagas (DC), baseada na participação popular, ocorre por meio da detecção e notificação de insetos suspeitos de serem vetores da DC aos Postos de Informação de Triatomíneos (PITs). Objetivo Compreender as ideias e concepções dos moradores em áreas rurais dos municípios da Microrregião de Saúde de Itaúna (MSI) em relação a aspectos relacionados à DC, seus vetores e serviços de saúde. Método Em 2016, foram realizados quatro grupos focais nos municípios da MSI. Esses grupos focais foram gravados, transcritos e analisados utilizando a técnica de análise de conteúdo. Neste processo, identificamos e categorizamos unidades de análise tanto dentro de cada grupo focal quanto entre eles. Resultados Descobrimos que há compreensão por parte de alguns moradores sobre a natureza da transmissão da DC, as características morfológicas e hábitos dos vetores, o encaminhamento do vetor para os PITs e o diagnóstico da DC. Também encontramos relatos da ausência de intervenções educacionais e de saúde relacionadas à DC. Conclusão Compreender as concepções e ideias sobre a DC das populações em áreas endêmicas é fundamental para desenvolver futuras estratégias envolvendo a participação popular.

Abstract Background The surveillance of Chagas disease (CD) based on public participation is carried out through the detection and notification of insects suspected of being vectors of CD to Triatomine Information Posts (TIPs). Objective To understand the ideas and conceptions of residents in rural areas of the municipalities of the Micro-region of Health de Itaúna (MHI) regarding aspects related to CD, its vectors, and health services. Method In 2016, four focus groups were conducted in the municipalities of MHI. These focus groups were recorded, transcribed, and analyzed using the content analysis technique. In this process, units of analysis, both within each focus group and between them, were identified and categorized. Results It was found that some residents have a good understanding of the nature of CD transmission and of the morphological characteristics and habits of the vectors, in addition to an understanding of the forwarding of the vector to TIPs, and the diagnosis of CD. Reports of the absence of education and health interventions related to CD were also found. Conclusion Understanding the conceptions and ideas about CD of populations in endemic areas is fundamental to developing future strategies involving public participation.

Agentes comunitários de saúde: percepção sobre os serviços de saúde relacionados à doença de Chagas / Community health agents: perception about health services related to Chagas' disease

Resumo Introdução A doença de Chagas ainda é um importante problema de saúde pública na América Latina, apresentando alta prevalência, ampla distribuição geográfica e grande impacto social. Vários serviços relacionados à doença de Chagas são solucionados na Atenção Primária à Saúde (APS). Na Estratégia Saúde da Família (ESF), destaca-se o agente comunitário de saúde (ACS), profissional responsável pela mediação entre a comunidade e as unidades básicas de saúde (UBS). Objetivo Apreender a percepção dos coordenadores da ESF e dos ACSs sobre o conhecimento a respeito da doença de Chagas e dos serviços de saúde relacionados nos municípios da microrregional de saúde de Itaúna, em Minas Gerais, Brasil. Método Foram aplicados questionários semiestruturados aos ACSs e realizados grupos focais com os coordenadores da ESF. Resultados Foi observado que, entre os profissionais, há ausência de informações básicas relacionadas à doença de Chagas; inexiste um protocolo/fluxograma de serviço; há uma ineficiência dos serviços de referência e contrarreferência; ocorre precariedade nas condições de trabalho; há ausência de capacitação dos profissionais e de ações de promoção à saúde nos municípios. Conclusão Este é o primeiro estudo abordando esta temática: percepção dos ACSs sobre a doença de Chagas e seus serviços. Sugere-se a extensão deste estudo a outras regiões do Brasil.

Abstract Background Chagas disease is still an important public health issue in Latin America, presenting high prevalence, broad geographical distribution and great social impact. Several services related to Chagas disease are solved in Primary Health Care (PHC). In the Family Health Strategy (FHS) it is highlighted the Community Health Agent (CHA), professional responsible for mediating between the community and units basics of health (UBH). Objective To raise the perception of the coordinators of the FHS and the CHAs about the knowledge on Chagas disease and related health services in the municipalities of the micro-regional health of Itaúna, Minas Gerais, Brazil. Method Semi-structured questionnaires were applied to the CHAs and focus groups were carried out with coordinators of the FHSs. Result It was observed that among professionals there is no basic information related to Chagas' disease; the lack of a service protocol/flowchart was noticed; inefficiency of reference and counter/reference services; precariousness in working conditions and training of professionals and absence of health promotion actions in municipalities. Conclusion This is the first study addressing this theme: perception of professionals about Chagas disease and its services. It is suggested that this study be extended to other regions of Brazil.

Immunohistochemical evidence of stress and inflammatory markers in mouse models of cutaneous leishmaniosis.

Leishmanioses are chronic parasitic diseases and host responses are associated with pro- or anti-inflammatory cytokines involved, respectively, in the control or exacerbation of infection. The relevance of other inflammatory mediators and stress markers has not been widely studied and there is a need to search for biomarkers to leishmaniasis. In this work, the stress and inflammatory molecules p38 mitogen-activated protein kinase, cyclooxygenase-2, migration inhibitory factor, macrophage inflammatory protein 2, heat shock protein 70 kDa, vascular endothelial factor (VEGF), hypoxia-inducible factors (HIF-1α and HIF-2α), heme oxygenase and galectin-3 expression were assessed immunohistochemically in self-controlled lesions in C57BL/6 mice and severe lesions in Balb/c mice infected with Leishmania amazonensis. The results indicated that the majority of molecules were expressed in the cutaneous lesions of both C57BL/6 and Balb/c mice during various phases of infection, suggesting no obvious correlation between the stress and inflammatory molecule expression and the control/exacerbation of leishmanial lesions. However, the cytokine VEGF was only detected in C57BL/6 footpad lesions and small lesions in Balb/c mice treated with antimonial pentavalent. These findings suggest that VEGF expression could be a predictive factor for murine leishmanial control, a hypothesis that should be tested in human leishmaniosis.

In vivo and in vitro Leishmania amazonensis infection induces autophagy in macrophages.

Autophagy is the primary mechanism of degradation of cellular proteins and at least two functions can be attributed to this biological phenomenon: increased nutrient supply via recycling of the products of autophagy under nutrient starvation; and antimicrobial response involved in the innate immune system. Many microorganisms induce host cell autophagy and it has been proposed as a pathway by which parasites compete with the host cell for limited resources. In this report we provide evidence that the intracellular parasite Leishmania amazonensis induces autophagy in macrophages. Using western blotting, the LC3II protein, a marker of autophagosomes, was detected in cell cultures with a high infection index. Macrophages infected with L. amazonensis were examined by transmission electronic microscopy, which revealed enlarged myelin-like structures typical late autophagosome and autolysosome. Other evidence indicating autophagy was Lysotracker red dye uptake by the macrophages. Autophagy also occurs in the leishmaniasis skin lesions of BALB/c mice, detected by immunohistochemistry with anti-LC3II antibody. In this study, autophagy inhibitor 3-methyladenine (3MA) reduced the infection index, while autophagy inductors, such as rapamycin or starvation, did not alter the infection index in cultivated macrophages, suggesting that one aspect of the role of autophagy could be the provision of nutritive support to the parasite.

Infection by Leishmania amazonensis in mice: a potential model for chronic hypoxia.

Hypoxia is a common feature of injured and infected tissues. Hypoxia inducible factors 1α and 2α (HIF-1α, HIF-2α) are heterodimeric transcription factors mediating the cellular responses to hypoxia and also the vascular endothelial growth factor (VEGF). VEGF is a cytokine which can be induced by hypoxia, whose pathogenic mechanisms are still unclear and which is the subject of debate. Murine cutaneous lesions during Leishmania amazonensis parasite infection are chronic, although they are small and self-controlled in C57BL/6 mice and severe in BALB/c mice. In the present study we examined the presence of hypoxia, HIF-1α, HIF-2α and VEGF during the course of infection in both mouse strains. Hypoxia was detected in lesions from BALB/c mice by pimonidazole marking, which occurred earlier than in lesions from C57Bl/6 mice. The lesions in the BALB/c mice showed HIF-1α and HIF-2α expression in the cytoplasm of macrophages and failed to promote any VEGF expression, while lesions in the C57BL/6 mice showed HIF-2α nuclear accumulation and subsequent VEGF expression. In conclusion, the animal models of leishmaniasis demonstrated a diversity of patterns of expression, cell localization and activity of the main transducers of hypoxia and may be useful models for studying the pathogenic mechanisms of HIF-1α and HIF-2α during chronic hypoxic diseases.

Hypoxia, hypoxia-inducible factor-1α and vascular endothelial growth factor in a murine model of Schistosoma mansoni infection.

Schistosomiasis mansoni is a chronic parasitic disease where much of the symptomatology is attributed to granuloma formation, an immunopathological reaction against Schistosoma eggs. To more clearly understand the immunopathology of schistosomiasis, the tissue microenvironment generated by S. mansoni infected mice was investigated. Using the hypoxia marker pimonidazole, we provide immunohistochemical evidence that hypoxia occurred in inflammatory cells infiltrated around the eggs and cells surrounding granulomas in the liver, intestine, spleen and lungs of infected mice. Hypoxia-inducible factor-1α (HIF-1α) was mainly expressed in inflammatory cells surrounding the eggs and in hepatocytes surrounding cellular and fibrocellular granulomas in infected mouse liver. HIF-1α expression was also verified in granulomas in the other tissues tested (intestine, spleen and lungs). Vascular endothelial growth factor (VEGF) expression was observed in the extracellular space surrounding inflammatory cells in liver granuloma. The VEGF expression pattern verified in infected mouse liver was very similar to that observed in the other tissues tested. A strong positive correlation occurred between pimonidazole binding and HIF-1α and VEGF expression in the tissues tested, except for lung. This work is the first evidence that infection by a helminth parasite, S. mansoni, produces a hypoxic tissue microenvironment and induces HIF-1α and VEGF expression.

The influence of copper, selenium and zinc on the response to the Montenegro skin test in subjects vaccinated against American cutaneous leishmaniasis.

We evaluated the relationship between the trace elements copper, zinc and selenium and the response to the Montenegro skin test (MST) in 172 volunteers vaccinated against American cutaneous leishmaniasis. The MST diameter was categorized as negative and in quartiles of positive response, constituting five groups. Trace element serum levels were analyzed by coupled plasma atomic emission spectrometry and hydride generation atomic absorption spectrometry, with study subjects classified into two groups depending on low or high levels of trace elements observed. MST-positive subjects had an MST diameter (mean+/-SD) of 10.35+/-4.64mm, with copper, selenium and zinc serum levels of 1433.7+/-665.7microg/l, 88.6+/-39microg/l and 999.2+/-366microg/l, respectively. The MST diameter was significantly different in the selenium groups only. The selenium levels also differed with the quartiles of the MST diameters of individuals testing positive (P<0.05). Our findings suggest that trace elements, particularly selenium, should be measured in future vaccine trials so that vaccine immunogenicity and response can be assessed and compared between different studies.