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- PublicaciónAcceso abiertoSeroprevalence and risk factors for Leptospira spp. in small ruminants of semi-arid zone in northeastern Colombia(2021-12-10)Leptospirosis in small ruminants is an economically important disease that causes important losses by pathologies of the reproductive tract. The present study aimed to estimate the seroprevalence and risk factors associated with Leptospira spp. in small ruminants under traditional husbandry systems. A cross-sectional epidemiological study was carried out in a sample of 1039 animals which included 793 sheep and 245 goats from 49 farms of 10 municipalities of northeastern areas of Colombia. The MAT test using a panel of 13 laboratory serovars was performed to diagnose the Leptospira spp. antibodies in the serum samples of animals. A structured questionnaire was filled in each farm to obtain information on putative risk factors, and its association with Leptospira spp. infection was detected by univariate and multivariate logistic regression. The general seroprevalence showed a rate of 13.9%, the 79.6% of farms showed at least one positive animal, the 14.2% and 0.4% of positive animals showed titers ≥ 1:100 and 1:200, respectively. The seroprevalence in sheep and goats showed a rate of 13.1% and 16.2%, respectively. The most common serovars in positive animals were Autumnalis (3.6%), Tarassovi (3.4%), Bratislava (2.9%), Mini (2.9%), Bataviae (1.4%), Canicola (0.3%), and Grippotyphosa (0.3%). The univariate and multivariate analysis showed as risk factors the absence of housing system (OR = 3.412 CI: 1.347–8.152), the absence of quarantine measures to new animals (OR = 1.371 CI: 0.943–1.978), and the protective factor identified was the use of Toggenburg breed (OR = 0.571 CI: 0.249–1.074). This exploratory study showed the Leptospira spp. positive small ruminants located in the northeastern areas of Colombia with titer associated with chronic and subclinical infection.
- PublicaciónAcceso abiertoPeroxisome proliferator-activated receptor delta-PPARδ agonist (L-165041) enhances bovine embryo survival and post vitrification viability(2022-05-22)The effect of L-165041 (PPARδ-agonist) on decreasing apoptosis and intracellular lipid content was assessed in fresh and vitrified–warmed in vitro-produced bovine embryos. It was hypothesised that the addition of L-165041 to the culture medium enhances development and cryopreservation. Oocytes were allocated to one of two treatments: control-standard culture medium, or L-165041 added to the medium on day 1 with no media change. Ultrastructure, cleavage, and blastocyst rates were evaluated in fresh, and in post-vitrification cultured embryos by optical and electronic microscopy. A subset of fresh embryos were fixed for TUNEL assay and for Sudan-Black-B histochemical staining. Vitrified–warmed embryos were assessed using MALDI-MS technique. Cleavage and blastocyst rates (control 49.4 ± 5.2, L-165041 51.8 ± 4.3) were not influenced by L-165041. The proportion of inner cell mass cells (ICM) was higher in fresh embryos, and the rate of total and ICM apoptosis was lower in L-165041. In warmed-embryos, total and ICM apoptosis was lower in L-165041. The overall hatching rate was higher in L-165041 (66.62 ± 2.83% vs 53.19 ± 2.90%). There was less lipid accumulation in fresh L-165041-embryos. In conclusion, the use of L-165041 is recommended to improve the viability of in vitro-derived bovine embryos.
- PublicaciónAcceso abiertoAminothiazole Ligand-Type Dioxo-Mo(VI) Complex Anchored on TiO2 Nanotubes for Selective Oxidation of Monoterpenes with Light and O2(2022-06-27)Selective Oxygen Atom Transfer to α-pinene, β-pinene, (R)-limonene and camphene by dioxo-Mo(VI)Ln complex {Ln = 2-aminothiazole-4-carboxylic acid} anchored on TiO2 nanotubes (TiO2-NT) using O2 as oxidant and UV light was studied at ambient conditions. The Catalytic system was characterized by FTIR, 1H NMR and 13C, and elemental analysis. Molecular oxygen reoxidizes the (Mo(IV)=O) reduced unit in the darkness, forming an oxo-peroxo-Mo intermediate. The catalyst under UV radiation transfers two oxygen atoms to the olefin. The α-pinene is found to be the most reactive monoterpene.
- PublicaciónAcceso abiertoDescripción de líneas celulares sanguíneas de pacientes con blastos provenientes de cinco ciudades de Colombia. Serie de casos(2020-06-02)Introducción: las leucemias constituyen un grupo complejo de hemopatías que por su etio-logía, patogenia y mortalidad, son consideradas un problema de salud pública. Su detección temprana permite la remisión oportuna para la confirmación del diagnóstico y el inicio del tratamiento.Objetivo: describir la celularidad sanguínea de pacientes con presencia de blastos en sangre periférica, provenientes de cinco ciudades de Colombia durante el año 2017.Métodos: estudio tipo descriptivo de serie de casos. A partir de hemogramas y sus respectivos extendidos de sangre periférica, se analizó cualitativa y cuantitativamente las células sanguí-neas de los pacientes con blastos que cumplieron con los criterios de inclusión.Resultados: fueron incluidos 39 pacientes con presencia de blastos de novo en sangre peri-férica procedentes de Cúcuta 48,7 %, Valledupar 33,3 %, Tunja 10,3 %, Socorro 5,1 % y Villavi-cencio 2,6 %. El 100 % eran afiliados al sistema general de seguridad social en salud en donde predominó el sexo femenino con el 54 %, la edad promedio para las mujeres fue de 32,5 años y para los hombres fue de 44,2 años. El 76 % de los pacientes presentó leucocitosis de moderada a grave y 69,2 % neutropenia. El 95 % presentó anemia, 51 % hipocromía y 38 % microcitos. El 74 % presentó trombocitopenia y 15 % macroplaquetas.Conclusiones: los hallazgos concuerdan con lo reportado por la literatura en relación con el predominio de la enfermedad de acuerdo con la edad y el sexo. La anemia, trombocitopenia y neutropenia, se mantienen como característica constante en los pacientes con leucemia.INVESTIGACIÓN ORIGINAL
- PublicaciónAcceso abiertoProtein sumoylation is crucial for phagocytosis in entamoeba histolytica trophozoites(2021-05-27)Posttranslational modifications provide Entamoeba histolytica proteins the timing and signaling to intervene during different processes, such as phagocytosis. However, SUMOylation has not been studied in E. histolytica yet. Here, we characterized the E. histolytica SUMO gene, its product (EhSUMO), and the relevance of SUMOylation in phagocytosis. Our results indicated that EhSUMO has an extended N-terminus that differentiates SUMO from ubiquitin. It also presents the GG residues at the C-terminus and the ΨKXE/D binding motif, both involved in target protein contact. Additionally, the E. histolytica genome possesses the enzymes belonging to the SUMOylation-deSUMOylation machinery. Confocal microscopy assays disclosed a remarkable EhSUMO membrane activity with convoluted and changing structures in trophozoites during erythrophagocytosis. SUMOylated proteins appeared in pseudopodia, phagocytic channels, and around the adhered and ingested erythrocytes. Docking analysis predicted interaction of EhSUMO with EhADH (an ALIX family protein), and immunoprecipitation and immunofluorescence assays revealed that the association increased during phagocytosis; whereas the EhVps32 (a protein of the ESCRT-III complex)-EhSUMO interaction appeared stronger since basal conditions. In EhSUMO knocked-down trophozoites, the bizarre membranous structures disappeared, and EhSUMO interaction with EhADH and EhVps32 diminished. Our results evidenced the presence of a SUMO gene in E. histolytica and the SUMOylation relevance during phagocytosis. This is supported by bioinformatics screening of many other proteins of E. histolytica involved in phagocytosis, which present putative SUMOylation sites and the ΨKXE/D binding motif.