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The haematophagy process by arthropods has been one of the main targets of studies in the parasite-host interaction, and the kissing-bug Rhodnius prolixus, vector of the protozoan Trypanosoma cruzi, has been one of the main models for such studies. Still in the 1980s, it was identified that among the salivary proteins for disrupting vertebrate host homeostasis, lipocalins were among the most relevant proteins for this process. Since then, 30 lipocalins have been identified in the salivary glands of R. prolixus, that promotes vasodilatation, prevents inflammation, act as anticoagulants and inhibits platelet aggregation. The present work aims to identify new lipocalins from R. prolixus, combining transcriptome and genome data. Identified new genes were mapped and had their structure annotated. To infer an evolutionary relationship between lipocalins, and to support the predicted functions for each lipocalin, all amino acid sequences were used to construct phylogenetic trees. We identified a total of 29 new lipocalins, 3 new bioaminogenic-biding proteins (which act to inhibit platelet aggregation and vasodilation), 9 new inhibitors of platelet aggregation, 7 new apolipoproteins and 10 lipocalins with no putative function. In addition, we observed that several of the lipocalins are also expressed in different R. prolxius tissues, including gut, central nervous system, antennae, and reproductive organs. In addition to newly identified lipocalins and a mapping the new and old lipocalins in the genome of R. prolixus, our study also carried out a review on functional status and nomenclature of some of the already identified lipocalins. Our study reinforces that we are far from understanding the role of lipocalins in the physiology of R. prolixus, and that studies of this family are still of great relevance.

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Introduction: Rhodnius (Hemiptera: Reduviidae: Triatominae) species are made up of haematophagous insect vectors for Trypanosoma cruzi (Chagas' disease aetiological agent) and T. rangeli, an infective parasite that is not pathogenic for vertebrate hosts. The study of their salivary protein diversity enables the obtention of characteristic one-dimensional electrophoretic profiles of some triatomine species; however, few reports have dealt with Rhodnius species salivary proteins electrophoretic patterns. Objective: To compare R. colombiensis, R. pallescens, R. pictipes, R. prolixus, and R. robustus' salivary proteins one-dimensional electrophoretic profiles. Materials and methods: SDS-PAGE was used for obtaining electrophoretic profiles of saliva from the species under study. The unweighted pair group method with arithmetic mean (UPGMA) was used for constructing a phenogram. Results: Electrophoretic profiles of soluble saliva had protein bands ranging from 15 to 45 kDa, thereby enabling the five species studied to be differentiated. The phenogram revealed two main groups, one formed by the Pictipes and Prolixus cis-Andean groups and another consisting of the Pallescens trans-Andean group. Conclusion: Differences were revealed regarding R. colombiensis, R. pallescens, R. pictipes, R. prolixus, and R. robustus electrophoretic profiles of salivary proteins; their variability facilitated constructing a phenogram which was taxonomically congruent with the groups from the genus Rhodnius.

Introducción. Las especies Rhodnius (Hemiptera: Reduviidae: Triatominae) están conformadas por insectos hematófagos vectores de Trypanosoma cruzi, agente etiológico de la enfermedad de Chagas, y T. rangeli, parásito infectivo pero no patógeno para el vertebrado. El estudio de la diversidad proteica de la saliva de estos insectos permite la obtención de perfiles electroforéticos unidimensionales característicos de algunas especies de triatominos. Sin embargo, el reporte de los patrones electroforéticos de proteínas salivales de las especies de Rhodnius ha sido escaso. Objetivo. Hacer un análisis comparativo de los perfiles electroforéticos unidimensionales de las proteínas salivales de R. colombiensis, R. pallescens, R. pictipes, R. prolixus y R. robustus. Materiales y métodos. Se obtuvieron los perfiles electroforéticos de la saliva de las especies en estudio mediante electroforesis en gel de poliacrilamida con dodecilsulfatosódico (Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis, SDS-PAGE) y se construyó un fenograma mediante el método UPGMA (Unweighted Pair Group Method Using Arithmetic Averages). Resultados. Los perfiles electroforéticos de las proteínas solubles de saliva presentaron bandas en un rango de masa aproximado de 15 a 45 kDa, los cuales permitieron diferenciar las cinco especies estudiadas. El fenograma reveló la existencia de dos grupos principales: uno conformado por los grupos cisandinos Pictipes y Prolixus y otro constituido por el grupo transandino Pallescens. Conclusiones. Existen diferencias en los perfiles electroforéticos de las proteínas salivales entre R. colombiensis, R. pallescens, R. pictipes, R. prolixus y R. robustus, cuya variabilidad permitió construir un fenograma congruente con los grupos del género Rhodnius.

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Juvenile hormones (JHs) are sesquiterpenoids synthesized by the corpora allata (CA). They play critical roles during insect development and reproduction. The first JH was described in 1934 as a "metamorphosis inhibitory hormone" in Rhodnius prolixus by Sir Vincent B. Wigglesworth. Remarkably, in spite of the importance of R. prolixus as vectors of Chagas disease and model organisms in insect physiology, the original JH that Wigglesworth described for the kissing-bug R. prolixus remained unidentified. We employed liquid chromatography mass spectrometry to search for the JH homologs present in the hemolymph of fourth instar nymphs of R. prolixus. Wigglesworth's original JH is the JH III skipped bisepoxide (JHSB3), a homolog identified in other heteropteran species. Changes in the titer of JHSB3 were studied during the 10-day long molting cycle of 4th instar nymph, between a blood meal and the ecdysis to 5th instar. In addition we measured the changes of mRNA levels in the CA for the 13 enzymes of the JH biosynthetic pathway during the molting cycle of 4th instar. Almost 90 years after the first descriptions of the role of JH in insects, this study finally reveals that the specific JH homolog responsible for Wigglesworth's original observations is JHSB3.

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Heme crystallization as hemozoin represents the dominant mechanism of heme disposal in blood feeding triatomine insect vectors of the Chagas disease. The absence of drugs or vaccine for the Chagas disease causative agent, the parasite Trypanosoma cruzi, makes the control of vector population the best available strategy to limit disease spread. Although heme and redox homeostasis regulation is critical for both triatomine insects and T. cruzi, the physiological relevance of hemozoin for these organisms remains unknown. Here, we demonstrate that selective blockage of heme crystallization in vivo by the antimalarial drug quinidine, caused systemic heme overload and redox imbalance in distinct insect tissues, assessed by spectrophotometry and fluorescence microscopy. Quinidine treatment activated compensatory defensive heme-scavenging mechanisms to cope with excessive heme, as revealed by biochemical hemolymph analyses, and fat body gene expression. Importantly, egg production, oviposition, and total T. cruzi parasite counts in R. prolixus were significantly reduced by quinidine treatment. These effects were reverted by oral supplementation with the major insect antioxidant urate. Altogether, these data underscore the importance of heme crystallization as the main redox regulator for triatomine vectors, indicating the dual role of hemozoin as a protective mechanism to allow insect fertility, and T. cruzi life-cycle. Thus, targeting heme crystallization in insect vectors represents an innovative way for Chagas disease control, by reducing simultaneously triatomine reproduction and T. cruzi transmission.

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RESUMEN Introducción. Trypanosoma cruzi, agente etiológico de la enfermedad de Chagas, puede transmitirse por vía oral tras la ingestión de alimentos o bebidas contaminadas. En la semana epidemiológica 14 del 2014, se notificaron dos casos de enfermedad aguda de Chagas en Paz de Ariporo, Casanare, entre trabajadores del sector de los hidrocarburos, episodio que motivó la investigación epidemiológica en el área. Objetivo. Caracterizar la población afectada, establecer medidas de control y confirmar el brote. Materiales y métodos. Se hizo una investigación de brote con los siguientes componentes: a) búsqueda de personas sintomáticas (cuadro clínico sugerente de enfermedad de Chagas según la definición de caso), para remitirlas a atención médica; b) aplicación de una encuesta entomológica en 192 de 197 viviendas; c) inspección sanitaria y análisis microbiológico de muestras de alimentos, y d) estudio de reservorios. La organización y el análisis de los datos se hicieron mediante estadística descriptiva con el programa Epi-Info 7.1.5. Asimismo, se establecieron los índices de infestación en el domicilio y el peridomicilio. Resultados. Se registraron 552 personas expuestas y se confirmaron por laboratorio 40 casos (7,2 %); siete casos se dieron en mujeres (17,5 %) y 33 en hombres (82,5%), es decir, en una relación de 1:5. La edad promedio fue de 39,1 (± 10,8) años, la tasa de ataque, de 7,2 %, y la letalidad, de 5 % (2/40). Los signos y síntomas incluyeron fiebre en el 100 % de los casos, cefalea en el 80 %, mialgias y artralgias en el 65 %, edema facial en el 55 %, y dolor abdominal en el 37,5 %. El tiempo promedio de incubación fue de 17 (3-21) días. El índice de infestación de Rhodnius prolixus fue de 3,3 % en el domicilio y de 2,2 % en el peridomicilio. En los cinco restaurantes inspeccionados, se encontraron condiciones sanitarias deficientes y alimentos con niveles de contaminación microbiológica inaceptables. Por último, un perro y dos zarigüeyas fueron positivos para los anticuerpos IgG en la prueba ELISA. Conclusiones. Mediante el análisis de las características epidemiológicas, ambientales y sanitarias, se confirmó un brote agudo de enfermedad de Chagas por exposición ocupacional y de posible transmisión oral, que podría ser el de mayor proporción reportado hasta la fecha en Colombia.

ABSTRACT Introduction: Trypanosoma cruzi, the etiological agent for Chagas disease, can be transmitted by oral intake of contaminated food or drinks. During epidemiological week 14 of 2014, two cases of acute Chagas disease were notified among hydrocarbons sector workers in Paz de Ariporo, Casanare. Objective: To characterize the affected population, to establish control and prevention measures and to confirm the outbreak. Materials and methods: We conducted an outbreak investigation that included the following components: a) Search for symptomatic people compatible with Chagas disease according to the case definition for their referral to medical services; b) entomological survey (192/197 houses); c) sanitary inspection and microbiological analysis of food samples; and d) study of reservoirs. Data management and analysis were done with Epi-Info 7.1.5 using descriptive statistics. We also calculated intradomicile and peridomicile triatomine infestation indexes. Results: We detected 552 exposed people; 40 had the disease (7.2%), of whom seven were women (17,5%) and 33, men (82.5%), i.e., a male-female ratio of 5:1. The mean age was 39.1 ± 10.8 years; the attack rate was 7.2% and lethality, 5% (2/40). Symptoms included fever (100% of cases), headache (80%), myalgia and arthralgia (65%), facial edema (55%), and abdominal pain (37.5%). The mean incubation time was 17 days (range: 3-21). Rhodnius prolixus domiciliary infestation index was 3.3 % and 2.2% in the peridomicile. In the five restaurants inspected sanitary conditions were deficient and food samples were microbiologically non-conforming. We found a dog and two opossums positive for IgG antibodies by ELISA. Conclusions: Environmental, sanitary and epidemiological conditions at the place confirmed an outbreak of Chagas diseases related to occupational exposure, possibly by oral transmission, which may be the largest to date in Colombia.

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INTRODUCTION: Domestic and wild triatomines in the department of Santander have an epidemiological impact, as recently they have been linked to outbreaks of acute Chagas disease. The analysis of their diversity and temporal variation contributes to the understanding of their biology and ecology in one of the most endemic areas of the country. OBJECTIVES: To analyze triatominae diversity in two regions of Santander. MATERIALS AND METHODS: We analyzed the triatomine records for Santander contained in the CINTROP-UIS entomology lab database. We grouped the information for two regions: the Middle Magdalena area and the Andean region, and for each one we designed species accumulation and range-abundance curves, we calculated diversity and equality indices, and we analyzed colonization and temporal variation or persistence of the community. RESULTS: Ninety five percent of triatomines came from the Andean area and 4.57% from Magdalena Medio, with nine and ten species each. The dominant species in the Andean area were Rhodnius prolixus and Triatoma dimidiata while in Magdalena Medio they were Rhodnius pallescens and Panstrongylus geniculatus. We found a greater diversity and richness in Middle Magdalena compared to the Andean area. The temporal variation showed persistence of communities over time. CONCLUSIONS: Results revealed differences in the diversity of the two regions and the potential of wild species to occupy artificial ecotopes. Triatomines intrusion and the recent involvement of wild species in the transmission of Trypanosoma cruzi emphasize the need to further investigate the ecology of these vectors in order to guide population control strategies.

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INTRODUCTION: Notice of triatomines in dwellings of some neighborhoods in Bucaramanga motivated the realization of this study.Objetive: To evaluate the intrusion of triatomines and mammals, as well as some risk factors in urban dwellings. MATERIALS AND METHODS: Triatomines were collected in a neighborhood in Bucaramanga, Santander, on a monthly basis during one year with participation of the community. Collection included manual search in lamp posts, use of light traps, animal bait, and chemical attractants in nearby forests. Reservoirs were collected with bait traps. Insects and mammals were identified and examined in order to determine their natural infection. Risk factors in homes were assessed by means of a social-environmental survey. RESULTS: Eleven adult specimens of Pastrongylus geniculatus, as well as 63 of Rhodnius pallescens were collected in the forest, recreational peridomiciliary areas, and houses. Even two females and 21 nymphs of R. pallescens were found in bedrooms. Two specimens of Didelphis marsupialis were captured in neighboring forests. Out of the eleven P. geniculatus captured, nine were examined. Of these, five were positive for Trypanosoma cruzi. It was not possible to establish a significant risk factor;however, the dwellings with report of triatomines were located nearer to the adjacent forest. CONCLUSIONS: The finding of intrusive triatominae species and mammals with T. cruzi in intradomiciliary and peridomiciliary areas and periurban forests prove the potential risk to acquire infection from these populations that dwell in urban housing adjacent to these ecotopes where the sylvan cycle is kept.

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INTRODUCTION: Trypanosoma cruzi, the etiological agent for Chagas disease, can be transmitted by oral intake of contaminated food or drinks. During epidemiological week 14 of 2014, two cases of acute Chagas disease were notified among hydrocarbons sector workers in Paz de Ariporo, Casanare. OBJECTIVE: To characterize the affected population, to establish control and prevention measures and to confirm the outbreak. MATERIALS AND METHODS: We conducted an outbreak investigation that included the following components: a) Search for symptomatic people compatible with Chagas disease according to the case definition for their referral to medical services; b) entomological survey (192/197 houses); c) sanitary inspection and microbiological analysis of food samples; and d) study of reservoirs. Data management and analysis were done with Epi-Info 7.1.5 using descriptive statistics. We also calculated intradomicile and peridomicile triatomine infestation indexes. RESULTS: We detected 552 exposed people; 40 had the disease (7.2%), of whom seven were women (17,5%) and 33, men (82.5%), i.e., a male-female ratio of 5:1. The mean age was 39.1 ± 10.8 years; the attack rate was 7.2% and lethality, 5% (2/40). Symptoms included fever (100% of cases), headache (80%), myalgia and arthralgia (65%), facial edema (55%), and abdominal pain (37.5%). The mean incubation time was 17 days (range: 3-21). Rhodnius prolixus domiciliary infestation index was 3.3 % and 2.2% in the peridomicile. In the five restaurants inspected sanitary conditions were deficient and food samples were microbiologically non-conforming. We found a dog and two opossums positive for IgG antibodies by ELISA. CONCLUSIONS: Environmental, sanitary and epidemiological conditions at the place confirmed an outbreak of Chagas diseases related to occupational exposure, possibly by oral transmission, which may be the largest to date in Colombia.

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Resumen Introducción: Los triatominos domiciliados y silvestres constituyen un problema de impacto epidemiológico en el departamento de Santander, pues se han asociado recientemente con brotes agudos de la enfermedad de Chagas, por lo cual el análisis de su diversidad y variación temporal contribuye al conocimiento de su biología y ecología en una de las áreas más endémicas del país. Objetivo: Analizar la diversidad de triatominos en dos regiones de Santander. Materiales y métodos: Se analizó la información de la base de datos del Laboratorio de Entomología del Centro de Investigaciones en Enfermedades Tropicales de la Universidad Industrial de Santander (CINTROP-UIS), la cual contiene registros de triatominos en Santander. La información se separó en dos regiones, el Magdalena Medio y la zona andina, para cada una de las cuales se diseñaron curvas de acumulación de especies y de rango de abundancia, se calcularon los índices de diversidad y de igualdad, se analizó la colonización y se evaluó la variación temporal o persistencia de la comunidad. Resultados: El 95 % de los triatominos provenía de la zona andina y, el 4,57 %, del Magdalena Medio, con nueve y diez especies, respectivamente. Se encontró mayor diversidad y riqueza en el Magdalena Medio en comparación con la zona andina. Las especies dominantes en la zona andina fueron Rhodnius prolixus y Triatoma dimidiata, mientras que en Magdalena Medio fueron Rhodnius pallescens y Panstrongylus geniculatus. La variación temporal mostró persistencia de las comunidades en el tiempo. Conclusiones:. Los resultados evidenciaron diferencias en la diversidad de las dos regiones, además del potencial de las especies silvestres para ocupar ecótopos artificiales. La intrusión de triatominos y la reciente incriminación de especies silvestres en la transmisión de Trypanosoma cruzi, indican la necesidad de un mayor conocimiento de la ecología de estos vectores para orientar las estrategias de control.

Abstract Introduction: Domestic and wild triatomines in the department of Santander have an epidemiological impact, as recently they have been linked to outbreaks of acute Chagas disease. The analysis of their diversity and temporal variation contributes to the understanding of their biology and ecology in one of the most endemic areas of the country. Objectives: To analyze triatominae diversity in two regions of Santander. Materials and methods: We analyzed the triatomine records for Santander contained in the CINTROPUIS entomology lab database. We grouped the information for two regions: the Middle Magdalena area and the Andean region, and for each one we designed species accumulation and range-abundance curves, we calculated diversity and equality indices, and we analyzed colonization and temporal variation or persistence of the community. Results: Ninety five percent of triatomines came from the Andean area and 4.57% from Magdalena Medio, with nine and ten species each. The dominant species in the Andean area were Rhodnius prolixus and Triatoma dimidiata while in Magdalena Medio they were Rhodnius pallescens and Panstrongylus geniculatus. We found a greater diversity and richness in Middle Magdalena compared to the Andean area. The temporal variation showed persistence of communities over time. Conclusions: Results revealed differences in the diversity of the two regions and the potential of wild species to occupy artificial ecotopes. Triatomines intrusion and the recent involvement of wild species in the transmission of Trypanosoma cruzi emphasize the need to further investigate the ecology of these vectors in order to guide population control strategies.

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Introducción: La notificación de triatominos en las viviendas de algunos barrios de Bucaramanga motivó la realización de este estudio. Objetivo: Evaluar la intrusión de triatominos y mamíferos, así como algunos factores de riesgo para la enfermedad de Chagas en viviendas urbanas. Materiales y métodos: En un barrio de Bucaramanga, Santander, se recolectaron triatominos mensualmente durante un año con participación comunitaria mediante búsqueda manual en el alumbrado público, y el uso de trampas de luz, cebo animal y atrayentes químicos en el bosque cercano. Los reservorios se recolectaron con trampas cebadas. Los insectos y mamíferos se determinaron y examinaron para establecer su infección natural. Los factores de riesgo de las viviendas se midieron mediante una encuesta sobre factores sociales y ambientales. Resultados: Se recolectaron 11 adultos de Panstrongylus geniculatus y 63 de Rhodnius pallescens en el bosque, en zonas de recreación en el peridomicilio y en el domicilio, incluidas dos hembras y 21 ninfas de R. pallescens en dormitorios. Se capturaron dos ejemplares de Didelphis marsupialis en el bosques adyacente. De los 11 individuos de P. geniculatus capturados, se examinaron nueve, de los cuales cinco fueron positivos para Trypanosoma cruzi (56 %); de los 63 individuos de R. pallescens capturados, se examinaron ocho, cuatro de los cuales fueron positivos para T. cruzi (50 %). De dos especímenes de D. marsupiales capturados, uno fue examinado y se encontró que era positivo para T. cruzi. No se pudo establecer un factor de riesgo significativo, sin embargo, las viviendas con reporte de triatominos se encontraban más cerca del bosque adyacente. Conclusiones: El hallazgo de especies de triatominos intrusivas y de mamíferos con T. cruzi en el domicilio y el peridomicilio, así como en los bosques periurbanos, demuestra el riesgo de infección en las poblaciones que habitan en viviendas urbanas adyacentes a los ecótopos donde se mantiene el ciclo silvestre.

Abstract Introduction: Notice of triatomines in dwellings of some neighborhoods in Bucaramanga motivated the realization of this study. Objetive: To evaluate the intrusion of triatomines and mammals, as well as some risk factors in urban dwellings. Materials and methods: Triatomines were collected in a neighborhood in Bucaramanga, Santander, on a monthly basis during one year with participation of the community. Collection included manual search in lamp posts, use of light traps, animal bait, and chemical attractants in nearby forests. Reservoirs were collected with bait traps. Insects and mammals were identified and examined in order to determine their natural infection. Risk factors in homes were assessed by means of a social-environmental survey. Results: Eleven adult specimens of Pastrongylus geniculatus, as well as 63 of Rhodnius pallescens were collected in the forest, recreational peridomiciliary areas, and houses. Even two females and 21 nymphs of R. pallescens were found in bedrooms. Two specimens of Didelphis marsupialis were captured in neighboring forests. Out of the eleven P. geniculatus captured, nine were examined. Of these, five were positive for Trypanosoma cruzi. It was not possible to establish a significant risk factor; however, the dwellings with report of triatomines were located nearer to the adjacent forest. Conclusions: The finding of intrusive triatominae species and mammals with T. cruzi in intradomiciliary and peridomiciliary areas and periurban forests prove the potential risk to acquire infection from these populations that dwell in urban housing adjacent to these ecotopes where the sylvan cycle is kept.

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