Transmission-blocking compound candidates against Plasmodium vivax using P. berghei as an initial screening

BACKGROUND Different strategies for improvement of malaria control and elimination are based on the blockage of malaria parasite transmission to the mosquito vector. These strategies include the drugs that target the plasmodial sexual stages in humans and the early developmental stages inside mosquitoes. OBJECTIVES Here we tested Malaria Box compounds in order to evaluate their activity against male and female gametocytes in Plasmodium berghei, mosquito infection in P. vivax and ookinete formation in both species. METHODS/FINDINGS The membrane feeding assay and the development of ookinetes by a 24 h ex vivo culture and the ookinete yield per 1000 erythrocytes were used to test transmission-blocking potential of the Malaria Box compounds in P. vivax. For P. berghei we used flow cytometry to evaluate male and female gametocyte time course and fluorescence microscopy to check the ookinete development. The two species used in this study showed similar results concerning the compounds' activity against gametocytes and ookinetes, which were different from those in P. falciparum. In addition, from the eight Malaria Box compounds tested in both species, compounds MMV665830, MMV665878 and MMV665941 were selected as a hit compounds due the high inhibition observed. CONCLUSION Our results showed that P. berghei is suitable as an initial screening system to test compounds against P. vivax.

Presence of trypanosomatids, with emphasis on Leishmania, in Rodentia and Didelphimorphia mammals of a rural settlement in the central Amazon region

BACKGROUND Trypanosomatids are widespread and cause diseases - such as trypanosomiasis, sleeping sickness, Chagas disease, and cutaneous and visceral leishmaniasis - in animals and humans. These diseases occur in both rural and urban regions due to unplanned growth and deforestation. Thus, wild and synanthropic reservoir hosts living in residential areas are risk factors. OBJECTIVE We aimed to evaluate the diversity of small mammals (rodents and marsupials), and the occurrence of trypanosomatids, especially Leishmania, in the rural settlement of Presidente Figueiredo, Amazonas. METHODS Animals were collected using Sherman, Tomahawk, and Pitfall traps along 16 trails in four landscapes: continuous forest, forest with planting, planting, and peridomiciliar. Leishmania sp. was detected in liver samples by polymerase chain reaction targeting kDNA. FINDINGS Diversity was higher in forests with planting and lower around residences. In total, 135 mammals (81 rodents and 54 marsupials covering 14 genera) were captured. Rodents presented infection rates (IR) of 74% and marsupials of 48%. Rodents in domicile landscapes presented a higher IR (92.9%), while marsupials showed a higher IR in forests (53.3%). MAIN CONCLUSIONS The results suggest high prevalence of trypanosomatids across 12 mammalian genera possibly involved as reservoir hosts in the enzootic transmission of leishmaniasis in the Amazon's rural, peridomiciliar landscape.

Contenido de grasa saturada y trans en panes de panaderías de la ciudad de Medellín, Colombia / Saturated and trans fat content in the breads of bakeries in Medellín, Colombia

ANTECEDENTES: Se desconoce el contenido de grasas saturada (GS) y trans (Gtrans) en panes sin etiqueta y sin vigilancia por entidad regulatoria de Colombia. PROPÓSITO: Comparar el contenido de GS y Gtrans en panes de algunas panaderías de Medellín con lo reglamentado: 0,5 g/50 g de pan, para ambos tipos de grasa según resolución 2508 de 2012 del Ministerio de Salud. MATERIALES Y MÉTODOS: Se muestrearon 45 panes de tres tipos (aliñado, leche y croissant) en tres niveles socioeconómicos (NSE) según ubicación de la panadería. Se cuantificó grasa total gravimétricamente y GS y Gtrans por cromatografía de gases. RESULTADOS: El porcentaje de GS y Gtrans con respecto a la grasa total extraíble fue 43,8% y 0,6% en pan aliñado, 37,4% y 0,6% en pan leche y 32,2% y 0,9% en pan croissant, sin diferencia significativa entre ellos (p= 0,155 y 0,184, respectivamente). CONCLUSIONES: Comparado con la resolución 2508, el contenido de GS fue mayor al límite establecido en resolución y el contenido de Gtrans fue menor en pan aliñado, leche o croissant. Los panes evaluados en las panaderías del NSE bajo contenían mayor Gtrans que los otros.

BACKGROUND: The content of saturated (GS) and trans (Gtrans) fats in unlabeled and breads that are not regulated by the Colombian government is unknown. PURPOSE: To compare the content of GS and Gtrans in breads of bakeries in Medellín with the following regulation: 0.5 g/50 g of bread, for both types of fat according to the 2012 Ministry of Health resolution #2508. MATERIALS AND METHODS: 45 breads of three types (seasoned, milk and croissant) were sampled at bakeries from three socioeconomic levels (NSE) according to the location. Total fat was quantified gravimetrically and GS and Gtrans by gas chromatography. RESULTS: The percentage of GS and Gtrans with respect to the total extractable fat was 43.8% and 0.6% in seasoned bread, 37.4% and 0.6% in milk bread and 32.2% and 0.9% in croissant bread, with no significant difference by bread type (p= 0.155 and 0.184, respectively). CONCLUSIONS: GS content of sampled breadswas greater than the limit established in the resolution. Gtrans content was lower in seasoned bread andmilk bread compared to croissant. The breads evaluated in the bakeries of lower NSE contained higher Gtrans than the others.

Diversity of biting midges Culicoides (Diptera: Ceratopogonidae), potential vectors of disease, in different environments in an Amazonian rural settlement, Brazil

Abstract INTRODUCTION: The Culicoides transmit a variety of pathogens. Our aim was to survey the Culicoides species occurring in an Amazonian rural settlement, comparing abundance, richness, and diversity in different environments. METHODS: Culicoides were captured using CDC light traps. The Shannon-Wiener (H') and Rényi indices were used to compare species diversity and evenness between environments, the equitability (J') index was used to calculate the uniformity of distribution among species, and similarity was estimated using the Jaccard similarity index. A permutational multivariate analysis of variance was applied to assess the influence of environment on species composition. A non-metric dimensional scale was used to represent the diversity profiles of each environment in a multidimensional space. RESULTS: 6.078 Culicoides were captured, representing 84 species (45 valid species/39 morphotypes). H' values showed the following gradient: forest > capoeira > peridomicile > forest edge. The equitability J' was greater in capoeira and forests compared to peridomiciles and the forest edge. The population compositions of each environment differed statistically, but rarefaction estimates indicate that environments of the same type possessed similar levels of richness. Species of medical and veterinary importance were found primarily in peridomiciles: C. paraensis, vector of Oropouche virus; C. insignis and C. pusillus, vectors of Bluetongue virus; C. filariferus, C. flavivenula, C. foxi, and C. ignacioi, found carrying Leishmania DNA. CONCLUSIONS: This study indicates that diversity was higher in natural environments than in anthropized environments, while abundance and richness were highest in the most anthropized environment. These findings suggest that strictly wild Culicoides can adapt to anthropized environments.

Chicken eggs as a surveillance tool for malaria and leishmaniasis vector presence

Abstract INTRODUCTION: Malaria and leishmaniases are transmitted by vectors during blood-feeding. Vector-infected animals develop antibodies against the vector's saliva. This study evaluated IgY antibody detection in the chicken eggs exposed to bites from Migonemyia migonei, Lutzomyia longipalpis and Anopheles aquasalis. METHODS: We used ELISA to quantify the antibody levels in the sera and exposed chicken eggs. RESULTS: High IgY levels were observed following immunization; furthermore, higher reactivity was observed in the eggs and species-specific immune response was observed post final immunization. CONCLUSIONS: Chicken eggs can be used as sentinels to surveil vector saliva antibodies.

Lutzomyia umbratilis from an area south of the Negro River is refractory to in vitro interaction with Leishmania guyanensis

BACKGROUND Lutzomyia umbratilis, the vector for Leishmania guyanensis in northern South America, has been found naturally infected with L. guyanensis only in areas north of the Negro and Amazon rivers. While populations of this sand fly species are also found in areas south of these rivers, these populations have never been reported to be infected and/or transmitting L. guyanensis. However, no studies on the corresponding host-parasite interactions are available. OBJECTIVES This study evaluated the interaction between Lu. guyanensis promastigotes and field-collected Lu. umbratilis sand flies from Rio Preto da Eva and Manacapuru, which are located to the north and south, respectively, of the Negro River. METHODS Procyclic and metacyclic attachment was quantified using an in vitro system. FINDINGS Low attachment of parasites to the midguts of insects collected from Manacapuru was detected. Conversely, greater binding of metacyclic parasites was observed in the midguts of insects collected from Rio Preto da Eva, and this attachment was more pronounced than that observed for procyclics (p < 0.03). MAIN CONCLUSIONS The Lu. umbratilis population from an area south of the Negro River has lower in vitro interaction with L. guyanensis. The higher attachment of L. guyanensis to midguts of insects from Rio Preto da Eva may suggest better vector competence. These findings are in accordance with previously reported epidemiological information of American cutaneous leishmaniasis (ACL) transmission in the Amazon.

First evidence of Zika virus venereal transmission in Aedes aegypti mosquitoes

BACKGROUND Aedes aegypti is considered the main Zika virus (ZIKV) vector, and is thought to be responsible for the 2015-2016 outbreak in Brazil. Zika positive Ae. aegypti males collected in the field suggest that vertical and/or venereal transmission of ZIKV may occur. OBJECTIVES In this study, we aimed to demonstrate that venereal transmission of ZIKV by Ae. aegypti can occur under laboratory conditions. METHODS Ae. aegypti collected in the city of Manaus, confirmed as negative for Zika, Dengue and Chikungunya virus by reverse transcription real-time polymerase chain reaction (RT-qPCR) (AaM3V- strain), were reared under laboratory conditions and used for the experiments. The ZIKV used in this study was isolated from a patient presenting with symptoms; ZIKV was confirmed by RT-qPCR. Experiment 1: virgin male mosquitoes of AaM3V- strain were intrathoracically inoculated with a ZIKV suspension; four days after injection, they were transferred to a cage containing virgin females of AaM3V- strain and left to copulate for five days. Experiment 2: virgin female mosquitoes of AaM3V- strain were orally infected with a ZIKV suspension by blood feeding membrane assay; nine days after blood feeding, they were placed in cages with Ae. aegypti AaM3V- virgin males and left to copulate for four days. After copulation, all mosquitoes were individually evaluated for viral infection by RT-qPCR. FINDINGS The mean infection rate in Experiment 1 and Experiment 2 was 45% and 35%, respectively. In both experiments, cycle threshold values ranged from 13 to 35, indicating the presence of viral genomes. MAIN CONCLUSION Ae. aegypti males intrathoracically inoculated with a ZIKV suspension are infected and can transmit the virus to uninfected females by mating. Moreover, Ae. aegypti females orally infected with a ZIKV suspension can transmit the virus to uninfected males by copulation. This study shows that ZIKV infection of Ae. aegypti mosquitoes occurs not only during blood feeding, but also during copulation.

The genital atrium armature of some Brazilian sand fly females (Diptera: Phlebotominae) / Armadura do átrio genital de algumas fêmeas de flebotomíneos brasileiros (Diptera: Phlebotominae)

Phlebotomine sand flies are insects of medical importance. Species in the Neotropical region are highly diverse. Some of these species are considered cryptic species because of their morphological similarity between adult females of different species make identification especially difficult. The aim of this study was to analyze and describe the armature in the genital atrium (AGA) of some adult female sand flies, in order to discover new taxonomic characters that make it possible to distinguish between species that would otherwise be treated as cryptic by analysis of the AGA. The AGA of 16 Phlebotomine sand fly species are described. Distinct differences were found in relation to the shape and size of the armature, the presence or absence of spines on the armature, and the shape, size, and grouping patterns of the spines. These characters made it possible to distinguish between the species studied.

Os flebotomíneos são insetos de importância médica. Na região Neotropical existe grande diversidade de espécies. Algumas dessas espécies são consideradas espécies crípticas devido às semelhanças morfológicas entre fêmeas adultas de diferentes espécies, tornando a identificação especialmente difícil. O objetivo deste estudo foi analisar e descrever a armadura no átrio genital (AAG) de algumas fêmeas adultas de flebotomíneos, a fim de descobrir novos caracteres taxonômicos que tornem possível a distinção por análise da AAG entre as espécies que poderiam ser tratadas como espécies crípticas. Foram descritas a AAG de 16 espécies de flebotomíneos. Diferenças distintas foram encontradas em relação à forma e ao tamanho da armadura, a presença ou ausência de espinhos na armadura, e a forma, tamanho e padrões de agrupamento dos espinhos. Esses caracteres tornou possível a distinção entre as espécies estudadas.

Suscetibilidade e resposta imune de mosquitos Anopheles (Diptera: Culicidae) da Região Amazônica Brasileira quando infectados experimentalmente por Plasmodium vivax

A malária é um problema de saúde pública. O Brasil é o país sul-americano que mais casos aporta todo ano, a maioria deles ocorridos na região Amazônica. Até o presente não há nenhuma vacina eficaz contra a malária. O controle dessa doença baseia-se principalmente no combate vetorial. Um dos desafios atuais é encontrar novas moléculas úteis para bloquear a transmissão da malária no vetor, sendo necessário para isso conhecer a biologia da interação entre os parasitos e seus hospedeiros. A maioria dos grupos de pesquisa utiliza como modelos de laboratórios combinações não naturais de Anopheles – Plasmodium. Neste trabalho foi avaliada a suscetibilidade ao P. vivax em espécies Amazônicas de Anopheles, fêmeas de Anopheles darlingi, An. albitarsis s.l., An. nuneztovari s.l. e An. triannulatus s.l. e An.aquasalis foram infectadas com P. vivax utilizando um sistema de infecção experimental por membrana artificial.

Todas as espécies de Anopheles estudadas foram suscetíveis à infecção por P. vivax, porém a taxa de infecção e o numero de oocistos variaram significativamente entre elas. An. aquasalis (Spearman rho = 0.255, n = 386, p < 0.01) e An. darlingi (rho =0.518; n = 54, p < 0.01) mostraram uma correlação positiva entre o número de gametócitos e o número de oocistos formados. Também foi avaliada a via JAK/STAT de resposta imune em A. aquasalis, durante a fase tardia da infecção, e em A. darlingi, no início da infecção. A expressão dos genes STAT, PIAS e NOS foi avaliada por q-PCR. Em An. aquasalis a expressão dos genes estudados foi induzida a partir de 8 dPI (PIAS e NOS) e 12 dPI (STAT),e começou a diminuir aos 14dPI, provavelmente indicando a indução transitória desses genes na fase tardia da infecção. Em An. darlingi não foi observada a ativação dessa via imune durante a fase inicial da infecção com P. vivax. Estudos futuros devem ser realizados para saber de que forma os genes regulados pela via JAK/STAT podem modular o desenvolvimento do P. vivax em An. aquasalis, e outras vias de sinalização devem ser estudadas na resposta de An. darlingi à infecção pelo Plasmodium.

Suscetibilidade e resposta imune de mosquitos Anopheles (Diptera: Culicidae) da Região Amazônica Brasileira quando infectados experimentalmente por Plasmodium vivax / Susceptibility and immune response of Anopheles mosquitoes (Diptera: Culicidae) of the Brazilian Amazon region when experimentally infected by Plasmodium vivax

A malária é um problema de saúde pública. O Brasil é o país sul-americano que mais casos aporta todo ano, a maioria deles ocorridos na região Amazônica. Até o presente não há nenhuma vacina eficaz contra a malária. O controle dessa doença baseia-se principalmente no combate vetorial. Um dos desafios atuais é encontrar novas moléculas úteis para bloquear a transmissão da malária no vetor, sendo necessário para isso conhecer a biologia da interação entre os parasitos e seus hospedeiros. A maioria dos grupos de pesquisa utiliza como modelos de laboratórios combinações não naturais de Anopheles – Plasmodium. Neste trabalho foi avaliada a suscetibilidade ao P. vivax em espécies Amazônicas de Anopheles, fêmeas de Anopheles darlingi, An. albitarsis s.l., An. nuneztovari s.l. e An. triannulatus s.l. e An.aquasalis foram infectadas com P. vivax utilizando um sistema de infecção experimental por membrana artificial...

Todas as espécies de Anopheles estudadas foram suscetíveis à infecção por P. vivax, porém a taxa de infecção e o numero de oocistos variaram significativamente entre elas. An. aquasalis (Spearman rho = 0.255, n = 386, p < 0.01) e An. darlingi (rho =0.518; n = 54, p < 0.01) mostraram uma correlação positiva entre o número de gametócitos e o número de oocistos formados. Também foi avaliada a via JAK/STAT de resposta imune em A. aquasalis, durante a fase tardia da infecção, e em A. darlingi, no início da infecção. A expressão dos genes STAT, PIAS e NOS foi avaliada por q-PCR. Em An. aquasalis a expressão dos genes estudados foi induzida a partir de 8 dPI (PIAS e NOS) e 12 dPI (STAT),e começou a diminuir aos 14dPI, provavelmente indicando a indução transitória desses genes na fase tardia da infecção. Em An. darlingi não foi observada a ativação dessa via imune durante a fase inicial da infecção com P. vivax. Estudos futuros devem ser realizados para saber de que forma os genes regulados pela via JAK/STAT podem modular o desenvolvimento do P. vivax em An. aquasalis, e outras vias de sinalização devem ser estudadas na resposta de An. darlingi à infecção pelo Plasmodium...

Factores de riesgo ambientales y componentes del síndrome metabólico en adolescentes con exceso de peso / Environmental risk factors and metabolic syndrome components in overweight youngsters

Introducción. Factores de riesgo ambientales, como el consumo de alimentos y la actividad física, son determinantes en la etiología del síndrome metabólico y sus componentes en jóvenes con exceso de peso. Objetivo. Explorar la asociación entre factores de riesgo ambientales y presencia de componentes del síndrome metabólico en jóvenes entre 10 y 18 años, con exceso de peso en Medellín. Materiales y métodos. Se llevó a cabo un estudio descriptivo de corte transversal. En la población de estudio se evaluaron la composición corporal por antropometría, la presión arterial, el perfil lipídico, la glucemia, la insulinemia, la ingestión de alimentos y la actividad física. Resultados. La prevalencia de los componentes del síndrome metabólico fue de 40,9 % para hipertrigliceridemia; 20,9 % para hipertensión; 15,6 % para c-HDL bajas; 4,0 % para circunferencia de cintura alta, y 0,9 % para la hiperglucemia; la prevalencia de síndrome metabólico fue de 3,1 %. Se encontró diferencia estadística (p<0,005) entre el consumo de kilocalorías, carbohidratos totales y simples, y la presencia de los componentes; no se encontró asociación entre el nivel de actividad física y la presencia de componentes (p>0,05). En el modelo de regresión logística se encontró una mayor probabilidad de tener, al menos, un componente si el joven era de sexo masculino (p=0,022), tenía un mayor índice de masa corporal (IMC) (p=0,019) y si se ubicaba en el cuarto cuartil de consumo de carbohidratos simples (p=0,036). Conclusiones. Los factores de riesgo ambientales asociados con los componentes del síndrome metabólico en este estudio fueron el mayor consumo de calorías, carbohidratos complejos y simples, todos relacionados directamente con el IMC; por el contrario, el nivel de actividad física, los antecedentes familiares y los personales no mostraron ninguna asociación. El síndrome metabólico sólo se presentó en jóvenes con obesidad.

Introduction. The environmental risk factors such as food intake and physival activity, are determinants in the etiology of metabolic syndrome in overweight adolescents. Objective. To explore the association between environmental risk factors and components presence of metabolic syndrome in overweight youngsters in Medellín. Materials and methods. Adolescents between the ages of 10 and 18 were selected for a cross sectional study. Body composition by anthropometry, blood pressure, lipid profile, glucose, insulin, food intake and physical activity level were assessed in the study population. Results. The prevalence for metabolic syndrome components of hypertriglyceridemia was 40.9%; hypertension, 20.9%; low HDLc, 15.6%; high waist circumference, 4.0%, and hyperglycemia, 0.9%; the overall prevalence of metabolic syndrome was 3.1%. There was a statistical difference (p<0.005) between the consumption of calories, simple and total carbohydrates and the presence of the components; no association was found between the level of physical activity and the presence of components (p>0.05). The logistic regression model showed a higher probability of having at least one component if the youngster was male (p=0.022), with a higher BMI (Body Mass Index)(p=0.019) and was located in the fourth simple carbohydrates consumption quartile (p=0.036). Conclusions. Environmental risk factors associated with components of metabolic syndrome were the increased consumption of calories, simple and complex carbohydrates, all directly related to the BMI. In contrast, the level of physical activity, family history and personal risk factors showed no association. The metabolic syndrome only occurred in youngsters with obesity.

Cladistic analysis of the Neotropical genera Cerqueirellum Py-Daniel, 1983, Coscaroniellum Py-Daniel, 1983 and Shelleyellum Py-Daniel & Pessoa, 2005 (Diptera: Simuliidae) / Análise cladística dos gêneros neotropicais Cerqueirellum Py-Daniel, 1983, Coscaroniellum Py-Daniel, 1983 e Shelleyellum Py-Daniel & Pessoa, 2005 (Diptera: Simuliidae)

Females of simuliid black flies are haematophagous insects and vectors of several pathogenic agents of human diseases such as the filarial worms Mansonella ozzardi and Onchocerca volvulus. The genus Cerqueirellum is one of the most important groups of vectors of mansonellosis and onchocerciasis diseases in South America, and the genera Coscaroniellum and Shelleyellum are phylogenetically close to Cerqueirellum. There is not yet an agreement among authors about the generic classification of the species which compose these three genera, being all lumped by some taxonomists within Psaroniocompsa. A cladistic analysis of all species of Coscaroniellum, Cerqueirellum, and Shelleyellum, based on 41 morphological characters were done. Species closely related to Cerqueirellum were included in the analysis. The genera Cerqueirellum, Coscaroniellum and Shelleyellum were demonstrated as consistent basal entities and well-defined monophyletic clades.

As fêmeas de piuns ou borrachudos da família Simuliidae são hematófagas e vetoras de diversos patógenos, destacando-se os vermes filarióides Mansonella ozzardi e Onchocerca volvulus. Dentre os grupos supra-específicos que são vetores de mansonelose e oncocercose na América do Sul, destaca-se o gênero Cerqueirellum. Os gêneros Coscaroniellum e Shelleyellum são filogeneticamente muito próximos a Cerqueirellum. Não existia concordância quanto à validade de Cerqueirellum e Coscaroniellum como clados supra-específicos, sendo ambos os gêneros incluídos, por uma escola taxonômica, como grupos de espécies em Psaroniocompsa. Neste trabalho é feita uma análise filogenética baseada em caracteres morfológicos dos três gêneros.. Os gêneros Cerqueirellum, Coscaroniellum e Shelleyellum. apresentaram-se como entidades basais válidas, consistentes e monofiléticas.

Primeiro registro de Aedes albopictus (Diptera: Culicidae) em Roraima, Brasil / First record of Aedes albopictus (Diptera: Culicidae) in the state of Roraima, Brazil

Aedes albopictus é registrado pela primeira vez no estado de Roraima, Brasil. Entre junho de 2006 e maio de 2007 foram coletadas três pupas e dez larvas, duas das quais chegaram à fase adulta, durante atividades de vigilância rotineiras em três bairros urbanos da cidade de Boa Vista. Embora essa espécie não seja incriminada como vetor primário do dengue, a sua presença pode favorecer a ligação entre os ciclos silvestre e urbano da febre amarela e de outras arboviroses no Brasil.

Aedes albopictus is registered for the first time in Roraima, Brazil. From June 2006 to May 2007, three pupae and ten larvae of Ae. albopictus were collected, during routine surveillance work in three urban neighborhoods in the city of Boa Vista. Two larvae reached adulthood as females. Although Ae. albopictus is not presently considered of primary importance in dengue transmission, its occurrence could favor a linkage between urban and forest cycles of yellow fever and other arboviruses in Brazil.