Resposta imune à saliva de flebotomíneos (diptera: psychodidae) em indivíduos residentes em áreas urbana e periurbana no nordeste do brasil

Visceral leishmaniasis (VL) has a wide geographical distribution in tropical and subtropical areas of the planet, which is a protozoan parasite of the genus Leishmania. This pathogen is transmitted to the host through the sandflies bite, with its saliva, the immune response that leads to both. In the state of Rio Grande do Norte, 85% of the sand flies captured is Lutzomyia longipalpis, but the second most abundant, Lutzomyia evandroi, it deserves emphasis because its wide distribution and eclectic behavior. The exposure of people living in endemic areas for the insect vector VL greatly increases the chances of infection. This study aimed to evaluate aspects of the epidemiological profile of VL in endemic areas of human and nonendemic in the metropolitan area of Natal, as well as verify the abundance and seasonal fluctuations of sandflies species in two counties endemic for VL. Were collected in the municipalities of Nísia Floresta, Parnamirim, São Gonçalo do Amarante and Macaíba, of which groups of females were separated for further dissection of the salivary glands and identification of species. The blood samples used were from individuals of two Natal s districts where it has never been reported cases of VL and neighborhoods of Parnamirim applicants who present cases of VL. In the municipality of Nísia Floresta, the most abundant species was L. evandroi with 38.39%, followed by L. longipalpis with 36.22%, L. walkeri 19.67% L. lenti 3.81%, L. wellcomei 1.39% and L. whitmani 0.52%. Already in Parnamirim the proportions were L. walkeri with 73.15%, L. evandroi with 10.55%, L. wellcomei 7.63%, L. longipalpis 6.37%, L. whitmani 1.46%, L. sordellii 0.52%, L. intermedia 0.21 and L. shanonni 0.1%. In both municipalities was observed higher abundance of species distributed in the initial months of the year, as February and March. The study showed that no difference in exposure to the vector of VL among individuals from endemic and non endemic area for this disease. But there are differences in exposure between individuals of L. longipalpis and L. evandroi, confirming the great powers of the first vector. It was also characterized as predominant phenotype in the population of endemic areas who had negative serologic responses to antigens of Leishmania and result in negative Montenegro skin test (DTH), indicating that much of the population hasn t been bitten by infected insects

Resposta imune à saliva de flebotomíneos (diptera: psychodidae) em indivíduos residentes em áreas urbana e periurbana no nordeste do brasil

Visceral leishmaniasis (VL) has a wide geographical distribution in tropical and subtropical areas of the planet, which is a protozoan parasite of the genus Leishmania. This pathogen is transmitted to the host through the sandflies bite, with its saliva, the immune response that leads to both. In the state of Rio Grande do Norte, 85% of the sand flies captured is Lutzomyia longipalpis, but the second most abundant, Lutzomyia evandroi, it deserves emphasis because its wide distribution and eclectic behavior. The exposure of people living in endemic areas for the insect vector VL greatly increases the chances of infection. This study aimed to evaluate aspects of the epidemiological profile of VL in endemic areas of human and nonendemic in the metropolitan area of Natal, as well as verify the abundance and seasonal fluctuations of sandflies species in two counties endemic for VL. Were collected in the municipalities of Nísia Floresta, Parnamirim, São Gonçalo do Amarante and Macaíba, of which groups of females were separated for further dissection of the salivary glands and identification of species. The blood samples used were from individuals of two Natal s districts where it has never been reported cases of VL and neighborhoods of Parnamirim applicants who present cases of VL. In the municipality of Nísia Floresta, the most abundant species was L. evandroi with 38.39%, followed by L. longipalpis with 36.22%, L. walkeri 19.67% L. lenti 3.81%, L. wellcomei 1.39% and L. whitmani 0.52%. Already in Parnamirim the proportions were L. walkeri with 73.15%, L. evandroi with 10.55%, L. wellcomei 7.63%, L. longipalpis 6.37%, L. whitmani 1.46%, L. sordellii 0.52%, L. intermedia 0.21 and L. shanonni 0.1%. In both municipalities was observed higher abundance of species distributed in the initial months of the year, as February and March. The study showed that no difference in exposure to the vector of VL among individuals from endemic and non endemic area for this disease. But there are differences in exposure between individuals of L. longipalpis and L. evandroi, confirming the great powers of the first vector. It was also characterized as predominant phenotype in the population of endemic areas who had negative serologic responses to antigens of Leishmania and result in negative Montenegro skin test (DTH), indicating that much of the population hasn t been bitten by infected insects

Influência do vírus da hepatite G (GBV-C) na resposta imune frente à infecção por Leishmania chagasi

GB virus type C (GBV-C) appears to promote a Th1 response and is associated with prolonged survival in HIV-infected people. L. chagasi causes a spectrum of illness that varies from severe visceral leishmaniasis, a disease that in the majority of cases is fatal if not treated, to self resolution of infection and development of positive DTH response that is protective against symptomatic disease. To determine if GBV-C viremia might influence the outcome of Leishmania infection, we characterized GBV-C status in a cohort of subjects residing in a L. chagasi endemic area in Brazil. GBV-C viremia was more prevalent in blood donors from urban than in periurban regions of Natal, Brazil (16% and 7.5% respectively). Evidence of prior GBV-C (anti-E2 antibodies) was detected in 24% and 12%of these groups respectively. Anti-E2 increased with age (p= 0.0121). No difference in GBV-C viremia was found in the DTH+ and VL groups (p= 0.269); however, subjects with visceral leishmaniasis were more likely to have anti-E2 than DTH+ subjects (p=0.0012), and DTH induration was smaller in subjects with E2 antibodies (4.5 mm) compared those without (7.12 mm) (p= 0.002). Furthermore, the size of the Leishmania DTH response was greater in GBV-C viremica subjects (6.8 mm) compared to non-viremic subjects (3.3 mm; p= 0.0054). There findings suggest that GBV-C virus may promote a type 1 immune response that could influence the outcome of Leishmania infection

Perfil de memória e ativação de linfócitos T na leishmaniose visceral

Visceral leishmaniasis (VL) in Brazil is a disease caused by Leishmania infantum chagasi (L.i.chagasi). The clinical evolution post-infection depends on the vertebrate host immune response, which is genetically mediated. This study aimed to evaluate the immune response of individuals living in endemic area for VL in the state of the Rio Grande do Norte, considering individuals with VL under treatment (n = 9), recovered VL <1 year post treatment (n = 10), > 10 years posttreatment (n = 9), uninfected individuals living in endemic areas (n = 7), individuals that lost DTH response (n=6) and asymptomatic individuals for VL (n=9). Peripheral blood cells were evaluated in the presence and absence of soluble Leishmania antigens (SLA) and ex vivo, to determine activation, presence of regulatory cells and memory cells. The Leishmania parasitemia and anti-Leishmania antibodies were determined respectively by qPCR and ELISA. Cells from individuals with VL under treatment showed less cell activation after stimulation with SLA for the markers CD4/CD69, CD8/CD69 and CD8/CD25 compared with VL post treatment treatment (p <0.001). Apparently uninfected individuals have a higher cell activation than symptomatic VL (p <0.001), with the exception of CD8/CD25 marker (p = 0.6662). On the other hand, in the ex-vivo group, significant differences were observed for CD4/CD69, CD8/CD69 and CD8/CD25 between the 4 groups due to increased cell activation present in cells of individuals symptomatic LV (p <0.001). VL cells under treatment, ex vivo, have a lower percentage of memory cells (CD4/CD45RO and CD8/CD45RO) than individuals VL post-treatment or control group (p = <0.01). Likewise, individuals with symptomatic VL have fewer regulatory cells when stimulated by SLA [CD4/CD25 (p = 0.0022) and CD4/FOXP3 (p = 0.0016)] and in the ex-vivo group (p = 0.0017). Finally, DNA isolated from recovered VL contained Leishmania DNA, supporting the hypothesis of non-sterile clinical cure for Leishmania infection. Recovered VL, even 10 years after treatment have high levels of memory cells, which may be due to the presence of stimulation, either by reexposure to Leishmania or non-sterile cure

Caracterização e composição florística de uma comunidade savânica no Rio Grande do Norte, Brasil : subsídios para a conservação

Studies on Brazilian biodiversity are still very few and can observe the difference of knowledge between the different regions of the country. This affirmation can be verified in the investigation to identify the rare species in Brazil and the key biodiversity areas (ACBs). In that study were identified for Brasil 2.256 rare species and 752 ACBs. The Rio Grande do Norte (RN) was the only Brazilian state that has not been identified any rare species and no ACBs, possibly due to the lack of floristic studies in this state. A particular area was selected for this study: an area of ecological tension with savanna physiognomy in Rio do Fogo, RN. This savanna community is represented in RN in a fragment and immersed in restinga and caatinga and was identified and described only through of radar imagens there are no studies to date in loco . We have prepared the following questions about this community savanna: 1) The region delimited and described by through of radar images by the RADAMBRASIL, 1976, can be associated of the Cerrado, in terms of floristic ?; 2) What is the floristic composition of this area? This area includes rare species, endemic or endangered? 3) What is the geographical and phytogeographical distribution of plant species registered in this area? 4) Those plant species registered are endemic or have affinity with other areas phytoecological Brazilian? To answer these questions we performed a floristic inventory of the August 2007 to September/2009. The results are presented in two chapters (manuscripts). The first chapter, titled "The Savannah Rio Grande do Norte: floristic links with other plant formations in the Northeast and Center-West Brazil" was submitted to the Revista Brasileira de Botância. Chapter 1 discusses the phytogeographical distribution of the species, by comparing floristic studies conducted in the Cerrado, Caatinga and Restinga in the Northeast and Cerrado of the Central Brazil. The analysis of data of this study and compilation with other studies indicated that: i) the record of 94 plant species; ii) of total species, about 64% are associated with the Cerrado, the second specialized bibliography, and about 78% as the List of Species of Flora of Brazil. However, about 73% of total species (94) are also distributed in the Caatinga, the Atlantic forest 64%, the Amazon forest 64%, the Pantanal 15% and the Pampa 12%. Floristically the data show that the community studied is influenced by other floras, has a structure where grasses dominate and also because of his appearance the same savanna then be classified as a Savana gramíneo-lenhosa do tabuleiro . Chapter 2, titled "Considerations on the flora of a savanna community in Rio Grande do Norte, northeastern Brazil: Subsidy key area for conservation" was submitted to the Revista Natureza e Conservação. This has the objective of improve the knowledge of flora of Rio Grande do Norte and to identify possible rare species and consequently increase the key areas of biodiversity in Brazil. The data indicated that: i) of 94 species registered in the study area, 40 were new records for the Rio Grande do Norte state; ii) These citations to unpublished state, Stylosanthes montevidensis Vogel (Fabaceae) and Aristida laevis (Nees) Kunth (Poaceae) are indicated for the first time to the Northeast of Brazil; iii) are registered in the area 24 species endemic to Brazil and 63 non-endemic; iv) Aspilia procumbens Baker (Asteraceae) registered in the area is considered a restricted species and micro endemic Rio Grande do Norte, ie rare species; v) Aspilia procumbens is also cited in the category of critically endangered species and Stilpnopappus cearensis Hubber (Asteraceae) a species vulnerable to extinction. This study shows a new area phytoecological in Rio Grande do Norte and indicates the area's potential to contribute with the sites of global significance for biodiversity conservation, either locally, regionally and nationally. This will certainly contribute to respond some targets set by the Global Strategy for Plant Conservation and the Convention on Biological Diversity such as the inventory of vegetal diversity in a region with little collection, which will provide data that contributes to questions and themes related to biodiversity.

Influência do vírus da hepatite G (GBV-C) na resposta imune frente à infecção por Leishmania chagasi

GB virus type C (GBV-C) appears to promote a Th1 response and is associated with prolonged survival in HIV-infected people. L. chagasi causes a spectrum of illness that varies from severe visceral leishmaniasis, a disease that in the majority of cases is fatal if not treated, to self resolution of infection and development of positive DTH response that is protective against symptomatic disease. To determine if GBV-C viremia might influence the outcome of Leishmania infection, we characterized GBV-C status in a cohort of subjects residing in a L. chagasi endemic area in Brazil. GBV-C viremia was more prevalent in blood donors from urban than in periurban regions of Natal, Brazil (16% and 7.5% respectively). Evidence of prior GBV-C (anti-E2 antibodies) was detected in 24% and 12%of these groups respectively. Anti-E2 increased with age (p= 0.0121). No difference in GBV-C viremia was found in the DTH+ and VL groups (p= 0.269); however, subjects with visceral leishmaniasis were more likely to have anti-E2 than DTH+ subjects (p=0.0012), and DTH induration was smaller in subjects with E2 antibodies (4.5 mm) compared those without (7.12 mm) (p= 0.002). Furthermore, the size of the Leishmania DTH response was greater in GBV-C viremica subjects (6.8 mm) compared to non-viremic subjects (3.3 mm; p= 0.0054). There findings suggest that GBV-C virus may promote a type 1 immune response that could influence the outcome of Leishmania infection

Perfil de memória e ativação de linfócitos T na leishmaniose visceral

Visceral leishmaniasis (VL) in Brazil is a disease caused by Leishmania infantum chagasi (L.i.chagasi). The clinical evolution post-infection depends on the vertebrate host immune response, which is genetically mediated. This study aimed to evaluate the immune response of individuals living in endemic area for VL in the state of the Rio Grande do Norte, considering individuals with VL under treatment (n = 9), recovered VL <1 year post treatment (n = 10), > 10 years posttreatment (n = 9), uninfected individuals living in endemic areas (n = 7), individuals that lost DTH response (n=6) and asymptomatic individuals for VL (n=9). Peripheral blood cells were evaluated in the presence and absence of soluble Leishmania antigens (SLA) and ex vivo, to determine activation, presence of regulatory cells and memory cells. The Leishmania parasitemia and anti-Leishmania antibodies were determined respectively by qPCR and ELISA. Cells from individuals with VL under treatment showed less cell activation after stimulation with SLA for the markers CD4/CD69, CD8/CD69 and CD8/CD25 compared with VL post treatment treatment (p <0.001). Apparently uninfected individuals have a higher cell activation than symptomatic VL (p <0.001), with the exception of CD8/CD25 marker (p = 0.6662). On the other hand, in the ex-vivo group, significant differences were observed for CD4/CD69, CD8/CD69 and CD8/CD25 between the 4 groups due to increased cell activation present in cells of individuals symptomatic LV (p <0.001). VL cells under treatment, ex vivo, have a lower percentage of memory cells (CD4/CD45RO and CD8/CD45RO) than individuals VL post-treatment or control group (p = <0.01). Likewise, individuals with symptomatic VL have fewer regulatory cells when stimulated by SLA [CD4/CD25 (p = 0.0022) and CD4/FOXP3 (p = 0.0016)] and in the ex-vivo group (p = 0.0017). Finally, DNA isolated from recovered VL contained Leishmania DNA, supporting the hypothesis of non-sterile clinical cure for Leishmania infection. Recovered VL, even 10 years after treatment have high levels of memory cells, which may be due to the presence of stimulation, either by reexposure to Leishmania or non-sterile cure

Estudo dos fatores associados à infecção chagásica em área endêmica do Rio Grande do Norte

The Chagas disease is a infectious and parasite disease that has as the causative agent a Trypanosoma cruzi, a protozoan parasite that can be transmitted to humans by the faeces of triatomines ( barbeiros ) in the blood-sucking. To understand the relationship between factors associated with chagasic infection and the risk of transmission of Trypanosoma cruzi, this work aimed to make a correlation between the results of serology, obtained by different immunological techniques, used for diagnosis of Chagas disease and risk factors to which the population of the city of Apodi-RN is exposed, to be considered a endemic area. The case-control study was conducted with 199 individuals, which initially was applied a questionary about socio-economic questions and some risk factors which they were exposed and also favor the spread of disease. Then was given the diagnosis by immunological techniques of serology by indirect hemagglutination, ELISA and indirect immunofluorescence. From the diagnosis, the subjects were divided into case group (presence of infection) and control group (no infection). Regarding the descriptive characteristics of the sample, were found a higher frequency of female individuals (59.3%), between 36 and 50 years of age (36.7%), with low education level (91%) and income monthly up to 1 minimum wage (67.8%). The serology, performed by three techniques of different principles, had a reactivity of 38.9% by Indirect Hemagglutination, 39.7% by ELISA and 38.7% by Indirect Immunofluorescence. As the result of the serology, 71 of samples showed reactivity in 2 or more techniques. On some risk variables, was found a significant relationship between individuals who had been bitten by the triatomines and had positive serology for Chagas disease (93.3%). Other variables of risk revealed individuals who had positive serology and had domestic animal (80.3%), lived in poorly maintained homes (97.2%) and near the forest (84.5%). A better understanding of the dynamics of transmission of T. cruzi and the risk factors that contribute to its occurrence in a region are needed to develop effective strategies for control of Chagas disease in these áreas

Avaliação da composição química, atividade antioxidante, antibacteriana, antinoceptiva, antiinflamatória e toxicidade do extrato metanólico e frações de folhas de Spondias sp. (Anacardiaceae)

Spondias sp. (Anacardiaceae), popularly known as cajá-umbu, is an endemic plant from Northeastern Brazil, where their leaves are widely used in folk medicine to treat inflammatory processes, while their fruits have a great agro industrial potential. This study was designed to evaluate hepatoprotective, antinociceptive, antioxidant, antimicrobial and anti-inflammatory properties, as well as the acute toxicity and repeated dose 28, using a methanolic extract (MES), a fraction rich in flavonoids (FRF) and a precipitate from Spondias sp.leaves. The antioxidant activity of them was valued to evaluate their free radical scavenger capacity by DPPH test, whereas MES and FRF were used to evaluate while the preventive action on carbon tetrachloride (CCl4)-induced hepatotoxicity. Seven groups (n=5) of female Wistar rats were used as follows: control group, CCl4-intoxicated group treated with EMS (500 mg/kg) for 7 days, three CCl4-intoxicated groups treated with FRF (25, 50 and 75 mg/kg) for 7 days and the CCl4-intoxicated group treated with Legalon ® (silimarina; (phytotherapeutic reference) (50 mg/kg; 7 days). MES and FRF showed a protective action against liver injury induced by CCl4, being observed a significant reduction of serum enzyme activity marker of liver damage (alanine transaminase and aspartate transaminase). On the other hand, the lipid peroxidation (SRAT) decrease, as well as the increase of glutathione content and enzyme activity of antioxidant defense system (SOD, CAT, GPx) toward near normal values indicated the ability of EMS to restore the oxidative imbalance induced by CCl4. The histological analysis confirmed the hepatoprotection, compared to degenerative changes in CCl4-treated group. This hepatoprotetor effect was similar to that shown by Legalon®. The in vitro high antioxidant capacity of extract (93.16 ± 1.00%) showed analogous results to those obtained by Carduus marianus BHT (reference standard). This fact explains the obtained results in vivo. Although no antimicrobial activity was detected, EMS and FRF promoted the antinociceptive effect induced in the second phase by the intraplantar formalin test, evidencing the anti-inflammatory action; confirmed by the carrageenan-induced peritonitis model. The evaluation of the mechanical allodynia (CFA a 80%) demonstrated the involvement of the Spondias sp. chemical composition in the anti-inflammatory activity toward the acute processes. The acute exposure and repeated dose during 28 days did not produce significant changes in the parameters that evaluate toxicity. Together the experimental results reveal, that Spondias sp. leaf extracts have a promising potential in pharmaceutical area, and due to its non-toxic condition present efficiency and security

Sistema de supervisão aérea baseado em navegação visual para detecção de anomalias em instalações de petróleo e gás

This work deals with the development of a prototype of a helicopter quadrotor for monitoring applications in oil facilities. Anomaly detection problems can be resolved through monitoringmissions performed by a suitably instrumented quadrotor, i.e. infrared thermosensors should be embedded. The proposed monitoring system aims to reduce accidents as well as to make possible the use of non-destructive techniques for detection and location of leaks caused by corrosion. To this end, the implementation of a prototype, its stabilization and a navigation strategy have been proposed. The control strategy is based on dividing the problem into two control hierarchical levels: the lower level stabilizes the angles and the altitude of the vehicle at the desired values, while the higher one provide appropriate references signals to the lower level in order the quadrotor performs the desired movements. The navigation strategy for helicopter quadrotor is made using information provided by a acquisition image system (monocular camera) embedded onto the helicopter. Considering that the low-level control has been solved, the proposed vision-based navigation technique treats the problem as high level control strategies, such as, relative position control, trajectory generation and trajectory tracking. For the position control we use a control technique for visual servoing based on image features. The trajectory generation is done in a offline step, which is a visual trajectory composed of a sequence of images. For the trajectory tracking problem is proposed a control strategy by continuous servovision, thus enabling a navigation strategy without metric maps. Simulation and experimental results are presented to validate the proposal