Análise do perfil imunológico e citohistológico durante a transmissão vertical de Trypanosoma cruzi em diferentes estágios da infecção experimental

Trypanosma cruzi is the causative agent of Chagas disease. This trypanosomiasis has become a global public health problem due to migration of Latin Americans to non-endemic countries. In Latin America with the succesful implementation of control domiciliated vector infestation and blood transfusion, the importance of congenital transmission has recently increased. Considering the tight regulation of immune system during gestation, we aimed to investigate the changes in the immune system caused by T.cruzi infection in the gestation outcome. T cruzi G and Y strain were used to infect female BALB/c mice before or after mating with non-infected male mice. The presence of vaginal plug was used as indicative of mating. Females were euthanized 8 days after confirmation of vaginal plug. We used three female control groups, only infected, only infected and non-infected and non-pregnant females. Two groups were infected before mating and other two were infected 4 days after confirmation of vaginal plug. The uterus and spleen were collected to immunochemistry, qPCR, immunofluorescence and cytokine analysis. Our results showed that despite the MMP’s identification being similarly among groups, T.cruzi higher virulent strain can impaire gestation outcome prior mating; the infection also increased cytokines like IFN-γ, IL-1β and IL-4; and leucocytes in uterine environment was altered, responding locally to systemic changes caused by T.cruzi infection. In conclusion this work suggests that T.cruzi infection can impaire gestation outcome and local response to sistemic infection was able to control the infection allowing pregnancy development in some conditions.

Percepção ambiental como ferramenta diagnóstica para o processo de integração entre uma unidade de conservação e a comunidade do entorno

It is remarkable the current planet’s situation of degradation and modification of natural assets and the considerable loss of the recovery power inherent to the ecosystems. Concomitant with this, all communities and species are suffering the consequences of these changes without planning. The creation of conservation units (UCs) through the National System of Conservation Units (SNUC) was a concrete action on the deliberateness of halting these processes, which, on the other hand, generated socio-environmental, geo-economical and cultural-political conflict of interests between traditional communities in the vicinity of these units, institutions, governmental entities and society in general. The country’s National Program of Environmental Education (ProNEA) provides the integration of the communities and UCs’ managers in a co-participative administration to solve these conflicts. The principles of Environmental Education (EA) leads the methodology found to change the socio-educational paradigms of traditional teaching, still existing in our society and intrinsically related to environmental problems, which are contrary to the dialogic pedagogy from Paulo Freire, that valorize popular knowledge, pro-active citizenship, as well as contrary to Ecopedagogy, that re-integrate human being on its natural environment, the Earth. One of the tools for starting environmental sensitization is the diagnosis by environmental perception of individuals. In this context, the objective of our work was to identify the environmental perception of Tenda do Moreno community located nearby Pau Furado State Park (PEPF) in Uberlândia – MG. To reach this objective, the research sought, in a first moment, to evaluate the environmental perception of residents of this community through semi-structured interviews applied in their homes and, in a second moment, we evaluated the environmental perception of community’ school students and made Environmental Education intervention activities with the intention to make children aware of the importance of conservation and function of PEPF. Using the Content analysis methodology, we found in nearly 60% of the 118 residents a systemic perception of nature, while approximately 32% expressed an anthropocentric perception. Mixed perceptions were found in 21%. A considerable part of the residents (47 individuals) indicated not knowing the park, although many of them recognize its importance. Among the 46 interviewed students, half expressed an anthropocentric perception of nature, while almost 36% had a systemic view. Seventeen children said they did not know the park and almost half of the students recognize some aspect of the importance of its existence. During the intervention activities, we had huge participation and dedication of students, beyond the massive expression of their personal views and daily experiences. In relation to the ten students that subjected the second evaluation about their environmental perception after the intervention, 80% showed systemic perception and emphasized the importance of conservation and of park. We believe that the continuity of the intervention activities could generate positive perspectives of socio-environmental effective changes in the daily school. Activities lead by Ecopedagogy and that encourage the citizen leadership in the young students are fundamental, while in the community, closer ties and dialog by UC’s managers would be important elements to generate effective change.

Respostas ecofisiológicas de Cybistax antisyphilitica Mart. (Ipê verde) em função das alterações na intensidade de luz

Light varies widely in both time and space in forest formation of “Bioma Cerrado”. Cybistax antisyphilitica occurs in areas typical of this biome, such as cerrado sensu stricto, “cerradões”, and altered areas. The aim of this study was to understand the morphological and physiological responses of C. antisyphilitica to alterations in light intensity. Juvenile plants (5 month of age) were taken to a fragment of semideciduous forest in Uberlândia-MG, and were divided into three treatments: 50 were maintained under the canopy (UC) 20 were kept in small gap (SG) and 20 were maintained under in full sun (FS). The daily courses of chlorophyll a fluorescence were made at the beginning, middle and end of dry season in 2015. At the end of the experiment measurements of chlorophyll content, gas exchange and growth were made. The plants showed dynamic photoinhibition as exhibited by reductions on Fv/Fm close to midday at the end of the dry season. Regarding the effective quantum yield (ΔF/Fm'), plants under FS showed reduced values that coincided with the higher values of electron transport rates (ETR). Plants under FS showed higher values of net CO2 assimilation rates, stomatal conductance, transpiration rates, water use efficiency and chlorophyll content compared to plants under UC. The stem diameter, dry mass of leaves and stem, total dry mass and relative growth rate were higher in plants under FS than plants under UC. On the other hand, plants under UC showed superior values of height, specific leaf area and leaf area ratio. Our results indicate that C. antisyphilitica has plasticity to survive in the contrasting light environments of the semideciduous forests, but this species was able to growth better under full sun conditions.

Manipulação gênica do protozoário Neospora caninum como ferramenta para o estudo das interações parasito-hospedeiro

Neospora caninum is an obligate intracellular parasite classified in the phylum Apicomplexa, characterized by the presence of the apical complex composed by micronemes proteins, rhoptries and dense granules, used by parasite during the adhesion and invasion process of the host cell. This is the mean event in infection pathogenesis generated by N. caninum and other parasites from the phylum Apicomplexa, promoting influence in the parasite biology and the interface between the parasite and its host. Therefore, molecular tools have been developed in order to identify and characterize these possible virulence factors. Thus, the present study sought to establish a specific system of genetic manipulation of N. caninum, searching for the improvement of the genetics manipulation of this parasite. So, we developed genetically depleted N. caninum to Rop9 rhoptry using the pU6-Universal CRISPR-Cas9 plasmid of T. gondii modified by the insertion of Ku80. The Rop9 depleted parasite showed important during initial phase of invasion and replication of the parasite, however it was not characterized as a potential virulence fator for N. caninum. Furthermore, T. gondii proteins were expressed in N. caninum by the use of specific vectors for this parasite, showing an heterologous system for the study of Toxoplasma proteins, due to the fact that Gra15 or Gra24 of type II T. gondii and Rop16 of type I T. gondii were expressed in N. caninum tachyzoites in a stable way and keept its biological phenotype, as already presented the former parasite, that naturaly expresses these proteins. In addition, it was observed that N. caninum induced an inflammasome activation through NLRP3, ASC and Caspase-1. IL-1R/MyD88 demonstrated an indirect pathway in the control of parasite replication. Furthermore, it was observed that this activation is dependent of the potassium efflux and that different strains of N. caninum keep this activation profile. However, T. gondii strains block this activation, making necessary a prior signal in order to active the inflamosome pathway. Type I T. gondii Rop16 was identified as responsible for blocking this activation, in a dependent way to the STAT3 activation. Therefore, the development of molecular tools and their application in N. caninum may prove to be useful to identify and characterize virulent factors involved in the pathogenesis by these two protozoans.