Estancia en Medellín, Colombia Febrero-Marzo 2016: Transferencia de Conocimientos PVCT15-53

Manejo de nuevas técnicas fluorescentes para la evaluación In Vivo de compuestos con actividad tripanocida y leishmanicida utilizando cepas transfectadas de Trypanosoma cruzi y Leishmania spp.CONACYT – Consejo Nacional de Ciencia y TecnologíaPROCIENCI

Genetic and toxinological divergence among populations of Tityus trivittatus Kraepelin, 1898 (Scorpiones: Buthidae) inhabiting Paraguay and Argentina

Autor de correspondencia: [email protected] by scorpions in genus Tityus is a public health problem in Tropical America. One of the most medically significant species is Tityus trivittatus, which is known to occur from southwest Brazil to central-northern and eastern Argentina. In this work, we studied the lethality, composition, antigenicity, and enzymatic activity of venom from a T. trivittatus population found further north in urban areas of eastern Paraguay, where it has caused serious envenomation of children. Our results indicate that the population is of medical importance as it produces a potently toxic venom with an LD50 around 1.19 mg/kg. Venom neutralization in preliminary mouse bioassays was complete when using Brazilian anti-T. serrulatus antivenom but only partial when using Argentinean anti-T. trivittatus antivenom. Venom competitive solid-phase enzyme immunoassays and immunoblotting from Argentinean and Paraguayan T. trivittatus populations indicated that antigenic differences exist across the species range. SDS-PAGE showed variations in type and relative amounts of venom proteins between T. trivitattus samples from Argentina and Paraguay. MALDI-TOF mass spectrometry indicated that while some sodium channel toxins are shared, including β-toxin Tt1g, others are population-specific. Proteolytic activity by zymography and peptide identification through nESI-MS/MS also point out that population-specific proteases may exist in T. trivitattus, which are postulated to be involved in the envenoming process. A time-calibrated molecular phylogeny of mitochondrial COI sequences revealed a significant (8.14%) genetic differentiation between the Argentinean and Paraguayan populations, which appeared to have diverged between the mid Miocene and early Pliocene. Altogether, toxinological and genetic evidence indicate that T. trivitattus populations from Paraguay and Argentina correspond to distinct, unique cryptic species, and suggest that further venom and taxonomic diversity exists in synanthropic southern South American Tityus than previously thought.Consejo Nacional de Ciencia y TecnologíaPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa de repatriación y radicación de investigadores del exteriorPrograma Paraguayo para el Desarrollo de la Ciencia y Tecnología. Programa Nacional de Incentivo a los Investigadore

Exposición potencial a plaguicidas y evaluación de daño en el ADN a través del ensayo cometa y test de micronúcleos y nivel de colinesterasa plasmática en niños de población rural

El objetivo general del proyecto es determinar la prevalencia de daño al ADN (evaluado a través del Ensayo Cometa), presencia de micronúcleos (evaluado a través del test CBMN: cytikinesis-block micronucleu) la alteración de la colinesterasa plasmática y su relación a exposiciones a plaguicidas en dos grupos de niños menores de 10 años que habitan en zonas rurales.CONACYT – Consejo Nacional de Ciencia y TecnologíaPROCIENCI

La salud de los ecosistemas, transmisión de enfermedades y alteración del hábitat: Importancia para la salud global y la conservación de la biodiversidad

El objetivo del trabajo fue examinar los efectos de la degradación del hábitat y del impacto antrópico sobre la salud de las poblaciones de mamíferos silvestres y los patrones de transmisión inter-especifica de parásitos entre animales silvestres, domésticos y humanos.CONACYT – Consejo Nacional de Ciencia y TecnologíaPROCIENCI

Genetic and toxinological divergence among populations of Tityus trivittatus Kraepelin, 1898 (Scorpiones: Buthidae) inhabiting Paraguay and Argentina

Envenoming by scorpions in genus Tityus is a public health problem in Tropical America. One of the most medically significant species is Tityus trivittatus, which is known to occur from southwest Brazil to central-northern and eastern Argentina. In this work, we studied the lethality, composition, antigenicity, and enzymatic activity of venom from a T. trivittatus population found further north in urban areas of eastern Paraguay, where it has caused serious envenomation of children. Our results indicate that the population is of medical importance as it produces a potently toxic venom with an LD50 around 1.19 mg/kg. Venom neutralization in preliminary mouse bioassays was complete when using Brazilian anti-T. serrulatus antivenom but only partial when using Argentinean anti-T. trivittatus antivenom. Venom competitive solid-phase enzyme immunoassays and immunoblotting from Argentinean and Paraguayan T. trivittatus populations indicated that antigenic differences exist across the species range. SDS-PAGE showed variations in type and relative amounts of venom proteins between T. trivitattus samples from Argentina and Paraguay. MALDI-TOF mass spectrometry indicated that while some sodium channel toxins are shared, including β-toxin Tt1g, others are population-specific. Proteolytic activity by zymography and peptide identification through nESI-MS/MS also point out that population-specific proteases may exist in T. trivitattus, which are postulated to be involved in the envenoming process. A time-calibrated molecular phylogeny of mitochondrial COI sequences revealed a significant (8.14%) genetic differentiation between the Argentinean and Paraguayan populations, which appeared to have diverged between the mid Miocene and early Pliocene. Altogether, toxinological and genetic evidence indicate that T. trivitattus populations from Paraguay and Argentina correspond to distinct, unique cryptic species, and suggest that further venom and taxonomic diversity exists in synanthropic southern South American Tityus than previously thought.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP

Evaluation of antiparasitary, cytotoxic and antioxidant activity and chemical analysis of Tarenaya spinosa (Jacq.) Raf. (Cleomaceae)

Active principles found in plants may aid in antiparasitic treatments, however it is important to evaluate if they do not have cytotoxicity. The leishmanicidal and trypanocidal activities of Tarenaya spinosa were evaluated, as well as the cytotoxic potential of their extracts, as well as the phytochemical and antioxidant profile. The phytochemical profile was described by Nuclear Magnetic Resonance of Hydrogen (1H-NMR) and High Performance Liquid Chromatography (HPLC-DAD). The antiparasitic activity was performed with the promastigote forms of Leishmania spp. and epimastigotes from Trypanosoma cruzi. Cytotoxicity was assessed using NCTC mammalian clone 929 fibroblasts. The antioxidant potential was assessed with the DPPH free radical. The ethanolic extract (EETS) and aqueous (EATS) presented terpenes, steroids, nitrogen compounds, sugars, phenolic compounds (simple phenylpropanoides and coumarins), flavonoids and chacolnas. The polyphenolic profile showed that caffeic acid was the major compound of both extracts. It was observed that the EETS showed a significant antileishmania activity against L. brasiliensis (LC50 81.75 μg/mL) and L. infantum (LC50 141.6 μg/mL), whereas EATS had low antileishmania activity. Against T. cruzi, the extracts presented LC50 > 1000 μg/mL. The extracts of T. spinosa present high antioxidant activity, with EETS having an IC50 of 377.7 μg/mL and EATS IC50 of 445.8 μg/mL. However, EETS was toxic to fibroblasts with an LC50 of 397.9 μg/mL, whereas no cytotoxicity was observed for EATS. Therefore, EATS is a promising source of antioxidant compounds since it does not present cytotoxicity. © 2019 South African Association of Botanist