Clinical, epidemiological and transmission cycle aspects of leishmaniasis urbanization in Barreiras, Bahia, Brazil.

Leishmaniasis remains one of the world's leading infectious diseases and a public health problem for Bahia and Brazil. We made a retrospective cohort study of leishmaniasis cases reported between 2007 and 2016 in the Barreiras city, an important agribusiness city whose urbanization process was recent. Leishmaniasis presented epidemiological data with similar characteristics of the disease in other regions of the Brazil, that is, with the highest prevalence of visceral leishmaniasis found in children, while cutaneous leishmaniais was found in adults. The disease presented an urban configuration with wide distribution in the Barreiras city. We found the vectors of the different clinical forms of the disease occurring in the urban area of Barreiras city, particularly the sand fly of the Lutzmyia longipalpis, Evandromyia sallesi and Nyssomyia intermedia species. More studies will be necessary to indentify whether these species are really incriminated in the urban transmission of the parasites in the urban areas. This study indicates the places of the spatio-temporal greatest occurrence and transmission of the disease in the urban zones of Barreiras city.

Epidemiology of Chagas disease in pregnant women and congenital transmission of Trypanosoma cruzi in the Americas: systematic review and meta-analysis.

OBJECTIVE: To estimate the prevalence of Chagas disease in pregnant women and the vertical transmission of the disease. METHODS: Observational studies were identified from eight electronic databases, and details on study design, population and prevalence of Chagas disease were extracted. The data were pooled using a random-effects model, and choropleth maps were created based on geopolitical regions and countries. RESULTS: The search identified 7788 articles, of which 50 were eligible. We observed a 9% prevalence of Chagas disease among pregnant women in the Americas (95% confidence interval [CI]: 8-10, I2  = 99.96%). High disease prevalence was identified in pregnant women in South American countries (12%, 95% CI: 11-13), while lower values were identified in pregnant women in North America (2%, 95% CI: 1-3). Countries with medium Human Development Index (HDI) had a higher prevalence of Chagas disease in pregnant women (15%, 95% CI: 13-16, I2  = 99.98%) than countries with high HDI (3%, 95% CI: 2-3). The rate of vertical transmission in the continent was 2% (95% CI: 1-2). The statistical analysis showed that this heterogeneity was explained by the study design, region of the Americas and mean income of the country. CONCLUSION: South and Central American countries have a high prevalence and vertical transmission of Chagas disease. Therefore, systematic screens for this disease during the prenatal period are necessary in addition to the diagnosis and treatment of children at risk for Trypanosoma cruzi infection.

OBJECTIF: Estimer la prévalence de la maladie de Chagas chez les femmes enceintes et la transmission verticale de la maladie. MÉTHODES: Des études d'observation ont été identifiées à partir de huit bases de données électroniques et des détails sur la concept de l'étude, la population et la prévalence de la maladie de Chagas ont été extraits. Les données ont été regroupées à l'aide d'un modèle à effets aléatoires et des cartes choroplèthes ont été créées en fonction des régions et des pays géopolitiques. RÉSULTATS: La recherche a identifié 7.788 articles, dont 50 étaient éligibles. Nous avons observé une prévalence de 9% de la maladie de Chagas chez les femmes enceintes dans les Amériques (intervalle de confiance [IC] à 95%: 8-10, I2 = 99,96%). Une prévalence élevée de la maladie a été identifiée chez les femmes enceintes dans les pays d'Amérique du Sud (12%, IC95%: 11-13), tandis que des valeurs plus faibles ont été identifiées chez les femmes enceintes d'Amérique du Nord (2%, IC95%: 1-3). Les pays à indice de développement humain (IDH) moyen présentaient une prévalence plus élevée de la maladie de Chagas chez les femmes enceintes (15%, IC95%: 13-16, I2 = 99,98%) que les pays à IDH élevé (3%, IC95%: 2 -3). Le taux de transmission verticale sur le continent était de 2% (IC95%: 1-2). L'analyse statistique a montré que cette hétérogénéité s'expliquait par le concept d'étude, la région des Amériques et le revenu moyen du pays. CONCLUSION: Les pays d'Amérique du Sud et d'Amérique centrale ont une prévalence élevée et de transmission verticale de la maladie de Chagas. Par conséquent, des dépistages systématiques de cette maladie pendant la période prénatale sont nécessaires en plus du diagnostic et du traitement des enfants à risque d'infection par Trypanosoma cruzi.

Protective actions of melatonin against heart damage during chronic Chagas disease.

Chronic cardiomyopathy is the most important clinical form of Chagas disease, and it is characterised by myocarditis that is associated with fibrosis and organ dysfunction. Alternative treatment options are important tools to modulate host immune responses. The main goal of this work was to evaluate the anti-inflammatory actions of melatonin during the chronic phase of Chagas disease. TNF-α, IL-10 and nitrite concentrations were evaluated as predictive factors of immune modulation. Creatine phosphokinase-MB (CK-MB), cardiac inflammatory foci and heart weight were assessed to evaluate the efficacy of the melatonin treatment. Male Wistar rats were infected with 1×10(5) blood trypomastigotes of the Y strain of Trypanosoma cruzi and kept untreated for 60 days to mimic chronic infection. After this period, the rats were orally treated with melatonin 50mg/kg/day, and the experiments were performed 90, 120, and 180 days post-infection. Melatonin treatment significantly increased the concentration of IL-10 and reduced the concentrations of NO and TNF-α produced by cardiomyocytes. Furthermore, it led to decreased heart weight, serum CK-MB levels and inflammatory foci when compared to the untreated and infected control groups. We conclude that melatonin therapy is effective at protecting animals against the harmful cardiac inflammatory response that is characteristic of chronic T. cruzi infection.

Immunomodulatory effect of the alkaloidic extract of Solanum lycocarpum fruits in mice infected with Schistosoma mansoni.

Schistosomiasis is a chronic disease caused by trematode flatworms of the genus Schistosoma; it accounts for more than 280,000 deaths annually. In this work we investigated the effect of the alkaloidic extract obtained by acid-base extraction of the dried fruits of Solanum lycocarpum on schistosomiasis. We used this extract at concentrations of 10, 20, and 40 mg/kg to treat mice infected with Schistosoma mansoni in different phases of the parasite cycle, and we compared its effect with that of the positive control praziquantel (60 mg/kg). We evaluated the results on the basis of the number of macrophages, eggs, and granulomas; we also assessed nitric oxide (NO) and interferon-gamma (IFN-γ) production. Animals treated with a daily dose of 10 or 20 mg/kg alkaloidic extract between the 37th and 41st day of infection showed increased number of macrophages, elevated NO and IFN-γ concentrations, and reduced number of eggs and granulomas in the liver. The alkaloidic extract of S. lycocarpum fruits displayed an immunomodulatory effect on mice infected with S. mansoni, so its potential to treat schistosomiasis deserves further studies.

Evaluation of the schistosomicidal activity of the steroidal alkaloids from Solanum lycocarpum fruits.

Solanum lycocarpum (Solanaceae), a Brazilian medicinal plant known as "wolf fruit," contains about 1.5% of glycoalkaloids in its dried fruits, consisting mainly of solamargine and solasonine. The present work reports the obtainment of the alkaloidic extract of the S. lycocarpum fruit by acid-base extraction and the isolation of the major alkaloid heterosides by chromatographic means, as well as the evaluation of their in vitro schistosomicidal activities. The in vitro schistosomicidal activities of the alkaloidic extract of S. lycocarpum fruits and its isolated steroidal alkaloids were undertaken against adult worms of Schistosoma mansoni. The alkaloidic extract (20, 32, and 50 µg mL(-1)), solasonine (50 µM), solamargine (32 and 50 µM), and equimolar mixture of glycoalkaloids (20, 32, and 50 µM) lead to the separation of all couple worms and extensive disruption on their teguments, such as sloughing, as well as their deaths within 24 h of incubation. In addition, the alkaloidic extract (10 and 15 µg mL(-1)), solasonine (50 µM), solamargine (10, 15, and 20 µM), and equimolar mixtures of glycoalkaloids (10 and 15 µM) reduced the development of eggs produced by the adult worms. Solamargine, containing the sugar chain moiety chacotriose, was more active than the solasonine, which contains solatriose sugar chain moiety. A synergistic effect was also observed for a mixture of solamargine and solasonine. Therefore, the alkaloidic extract of S. lycocarpum, and its major components, solamargine and solasonine, showed promising schistosomicidal activity.

Effects of dehydroepiandrosterone-sulfate (DHEA-S) and benznidazole treatments during acute infection of two different Trypanosoma cruzi strains.

A significant role for hormones in regulating the balance of Th1- and Th2-associated cytokines with a role in modulating diseases has been accumulating. Previously, we reported that dehydroepiandrosterone (DHEA), the most abundant steroid hormone synthesized by the adrenal cortex, markedly reduced the blood and tissue parasites in experimentally Trypanosoma cruzi-infected rats. Based on these findings, the main purpose of this study was to investigate the effect of dehydroepiandrosterone-sulfate ester (DHEA-S) therapy alone or in combination with benznidazole (BNZ) (recommended in Brazil for the treatment of T. cruzi infection) will be effective during the acute phase of two different lineages of T. cruzi strains: type I (Y strain) and type II (Bolivia strain) of T. cruzi. Administration of either DHEA-S or BNZ alone or in combination significantly reduced the Y strain parasite load as compared with untreated. Furthermore treatment with DHEA-S resulted in Bolivia strain clearance. This protective effect of DHEA-S was associated with the host's immune response, as evidence by enhanced levels of interferon-gamma and interleukin-2. DHEA-S treatment also increased peritoneal macrophages levels and nitrite production. DHEA-S treatment was effective in reducing the mortality rate as compared to BNZ alone or to combiner DHEA-S+BNZ treatment of T. cruzi Bolivia strain infected animals. These findings suggest that hormonal therapy may have a protective effect in the treatment of T. cruzi infection.