ABSTRACT The historic flight of cosmonaut Yuri Alekeseyevich Gagarin, in 1961, established the need for research regarding the physiological adaptations of the human body when exposed to the space environment. Since then, several morpho-functional transformations – varying between normal and pathological – have been identified within the organisms of astronauts subjected to the extremely disparate environments of the cosmos, consequently, comprehension and preparation of these transformations becomes essential, considering the possibilities (1) of returning to the Moon and (2) of initiating the trip to Mars. Accordingly, the purpose of this article – conceived as a narrative literature review – is to present the main aspects of the physiological modifications within the human body due to the extraterrestrial environment, with emphasis on cardiovascular, renal, hydroelectrolytic, hematological, immunological, respiratory, neurological, psychological, sensory, gastrointestinal, endocrine, musculoskeletal, integumentary, and genetic adaptations.

Abstract INTRODUCTION: Trypanosoma rangeli is a protozoan that infects several domestic and wild mammals and shows significant distribution in Latin American countries. T. rangeli infection is similar to Chagas disease, both in diagnostic and prophylactic terms. Thus, the objective of this work was to review the diagnostic aspects and use of T. rangeli as an immunogen for Trypanosoma cruzi infection. METHODS: For this elaboration, Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were adopted with descriptors derived from the Medical Subject Headings (MeSH) platform in the PubMed/MEDLINE and SciELO databases. The inclusion criteria were defined as original articles on "Trypanosoma rangeli" and diagnostic aspects of T. rangeli infection in humans and/or research on the possible vaccines developed using T. rangeli strains for T. cruzi infection. RESULTS: After applying the inclusion and exclusion criteria, 18 articles were procured, of which 4 addressed research on the possible vaccines developed using T. rangeli for T. cruzi infection in vertebrates and the remaining 14 predominantly dealt with the diagnostic aspects of T. rangeli infection in humans. CONCLUSIONS: In this study, we formulated a compilation of the essential literature on this subject, emphasizing the need for more accurate and accessible techniques for the differential diagnosis of infections caused by both protozoa, and underscored several prospects in the search for a vaccine for Chagas disease.

Este estudo investigou o efeito da exposição aguda do zinco (Zn) na histologia do fígado e testículos de lambari do rabo-amarelo (Astyanax aff. Bimaculatus). A exposição consistiu de seis concentrações de Zn, 0, 3, 5, 10, 15 e 20 mg/L por 96 horas de exposição. Fragmentos de fígado e testículos foram processados rotineiramente para inclusão em resina plástica a base de glicol metacrilato. Fragmentos de ossos, músculos, fígado e testículos foram desidratados e digeridos para quantificar os níveis teciduais da absorção de Zn. A exposição aguda a concentrações de acima de 10mg/L produziu alterações estruturais no fígado e gônada. As alterações encontradas no fígado foram: congestão vascular, diminuição do volume celular; deslocamento do núcleo dos hepatócitos, necrose; desarranjo na estrutura do cordonal; infiltrado leucocitário e vacuolização. As alterações encontradas nas gônadas foram ruptura de cisto, retardo no desenvolvimento das células da linhagem germinativa, núcleo picnótico, aglomerado de celular, deslocamento da parede do cisto e vacuolização. As alterações histológicas observadas foram compatíveis com o aumento da concentração de Zn no ambiente, comprometendo as funções hepáticas e reprodutivas, devido ao aumento no número de hepatócitos e redução na produção de espermatozoides.

This study investigated the effect of acute exposition to zinc (Zn) on histology of the liver and testes of yellow tail lambari (Astyanax aff. bimaculatus). The exposure consisted of six concentrations of Zn (0, 3, 5, 10, 15, and 20 mg/L) for 96 hours of exposure. Fragments of liver and testis were routinely processed and embedded in plastic resin based on glycol methacrylate. Fragments of bones, muscles, liver and testis were dehydrated and digested to quantify the absorption levels of Zn in the tissue. Acute exposure to concentrations above 10mg/L has produced structural changes in the liver and gonads. The changes found in the liver were vascular congestion; decrease of cellular volume; displacement of the hepatocyte nucleus; necrosis; disarrangement of cordon structure; leukocyte infiltrate and vacuolization. The changes found in the gonads were ruptured cyst, delayed development of germ cells, pyknotic nucleus, cell cluster, displacement of cyst wall and vacuolization. The histological changes observed were compatible with the increasing concentration of zinc in environment, compromising liver and reproductive functions, because there was an increase in relative frequency of hepatocytes and reduced sperm production