http://sgc.anlis.gob.ar/handle/123456789/1159 2026-05-20T22:01:40Z http://sgc.anlis.gob.ar/handle/123456789/2740 Title: Characterization of the venom apparatus of Oxyrhopus guibei (Squamata: Colubridae) Authors: Martinez, Matias Emanuel; Gonzalez, Karen Y; Sanchez, Matias Nicolas; Teibler, Gladys P; Peichoto, María Elisa Abstract: Oxyrhopus guibei is a conspicuous colubrid snake popular in the exotic pet trade that has been implicated in envenomation cases involving local and systemic clinical manifestations. This study aims to characterize the venom apparatus of O. guibei, including the composition and immunochemical reactivity of its secretion. The maxilla and fangs were examined using scanning electron microscopy, while the histology and histochemistry of the glands were analyzed via hematoxylin-eosin and periodic acid-Schiff (PAS), Alcian Blue pH 2.5, and Gomori's trichrome staining. Additionally, the protein profile was evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Tricine-SDS-PAGE, and cross-reactivity with bivalent and tetravalent bothropic antivenoms was assessed by Western blot. Anatomically, recurved teeth were observed in the anterior maxilla, followed by enlarged, deeply grooved posterior teeth (opisthoglyphous dentition). Histologically, Duvernoy's venom glands exhibited distinct structural and chemical characteristics compared to the supralabial glands; their secretory units are organized into lobules of predominantly serous acini composed of columnar cells with acidophilic cytoplasm and PAS-negative basal nuclei. The venom protein profile displayed bands ranging from ≈8.5 to 65 kDa, with a predominance of proteins migrating within molecular mass ranges consistent with snake venom metalloproteinases, which showed immunoreactivity with both antivenoms tested. In conclusion, O. guibei possesses a specialized venom delivery system consisting of modified anatomical structures designed to deliver a venom containing components reminiscent of bothropic venoms, primarily involved in prey subjugation and with the potential to cause envenomation in humans. This study provides preliminary insights into the venom of this species and underscores the need for further functional characterization to determine its potential toxicological relevance to humans. 2026-04-01T00:00:00Z http://sgc.anlis.gob.ar/handle/123456789/2648 Title: Complete Genome Classification System of Rotavirus alphagastroenteritidis: An Updated Analysis Authors: Díaz Alarcón, Ricardo; Salvatierra, Karina; Gómez Quintero, Emiliano; Liotta, Domingo Javier; Parreño, Viviana; Miño, Samuel Abstract: Rotavirus alphagastroenteritidis is the major causative agent of acute gastroenteritis in both children under the age of 5 and young mammals and birds globally. RVAs are non-enveloped viruses with a genome comprising 11 double-stranded RNA segments. In 2008, the Rotavirus Classification Working Group pioneered a comprehensive and complete RVA genome classification system, establishing a specific threshold, which measures the genetic distances between homologous genes. The aim of this study was to perform an updated systematic analysis of the genetic variability across all RVA genes. Our investigation involved assessing the established cutoff values for each RVA genome segment and determining the need for any updates. To achieve this objective, multiple sequence alignments were constructed for all 11 genes and one for each genotype with discrepancies. Also, pairwise distances along with their cutoff values were evaluated. The analyses provided insights into the current relevance of cutoff values, which remain applicable for the majority of genotypes. In conclusion, this study fortifies the current classification system by highlighting its robustness and accurate genotyping of Rotavirus alphagastroenteritidis. Description: Fil: Díaz Alarcón RG. Laboratory of Applied Molecular Biology (LaBiMAp), Faculty of Exacts, Chemical and Natural Sciences, National University of Misiones (UNaM); Misiones; Argentina.; Fil: Salvatierra K. Laboratory "MADAR", National University of Misiones (UNaM); Misiones; Argentina.; Fil: Gómez Quintero. Laboratory of Applied Molecular Biology (LaBiMAp), Faculty of Exacts, Chemical and Natural Sciences, National University of Misiones (UNaM); Misiones; Argentina.; Fil: Liotta DJ. Laboratory of Applied Molecular Biology (LaBiMAp), Faculty of Exacts, Chemical and Natural Sciences, National University of Misiones (UNaM); Misiones; Argentina.; Fil: Parreño, V. National Institute of Agricultural Technology (INTA), IncuINTA, De Las Cabañas y De los Reseros s/n; Buenos Aires; Argentina.; Fil: Miño SO. Laboratory of Applied Molecular Biology (LaBiMAp), Faculty of Exacts, Chemical and Natural Sciences, National University of Misiones (UNaM); Misiones; Argentina. 2025-01-31T00:00:00Z http://sgc.anlis.gob.ar/handle/123456789/2576 Title: Epidemiological characterization of lonomism in South America Authors: Melo Favalesso, Marilia; Valentim, Matheus; Guimarães, Ana Tereza Bittencourt; Peichoto, María Elisa Abstract: Lonomism is the envenomation caused by accidental contact with Lonomia caterpillars, and this is a public health priority in South America since it is relatively common but remains underestimated. This study presents an updated and integrative analysis of reliable global data from 1960 to 2020 on the epidemiology of this envenomation in the whole continent. A total of 13,186 notifications were recorded for South America: 13,056 (99.01%) in Brazil, 49 (0.37%) in Argentina, 43 (0.33%) in Colombia, 29 (0.22%) in Venezuela, 6 (0.05%) in Peru and 3 (0.02%) in French Guiana. The number of new locations reporting accidents has increased since the first formally notifications at the middle of the last century. Most of these locations are situated in Brazil, the pioneer in deeply researching the Lonomia genus and its impacts in public health. Most victims were males, in the economically productive age group, and accidental contact occurred more frequently in the upper limbs while doing activities outdoors in urban/rural areas. Regarding the determinants of clinical outcome, countries where patients received delayed medical care were associated with a higher number of moderate and/or severe cases, as well as a higher chance of progressing to death. Additionally, the longer the delay for accessing medical care, the higher the risk of developing systemic complications, thereby increasing the need for specific treatment. Our study also shows that accidents globally occurred more frequently in the summer months and in the beginning of autumn. Although having identified several shortcomings in the documents selected and verified that notifications are strongly biased by public policies adopted by each South American country, this study provides the first comprehensive assessment of lonomism in South America, demonstrating the increase in the number of accidents, and their expansion to other areas of the continent over time. Our findings will undoubtedly help guide the appropriate allocation of resources and implementation of prevention strategies and define priority criteria for epidemiological surveillance of this neglected tropical disease. Description: Fil: Melo Favalesso, Marilia. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto Nacional de Medicina Tropical (INMeT) - ANLIS "Dr. Carlos G. Malbrán". Almafuerte y Ámbar s/n; Argentina; Fil: Valentim, Matheus. IT University of Copenhagen; Denmark; Fil: Guimarães, Ana Tereza Bittencourt. Programa de Pós-Graduação em Biociências e Saúde, Universidade Estadual do Oeste do Paraná, Universitária n. 1619; Brazil; Fil: Peichoto, Maria Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto Nacional de Medicina Tropical (INMeT) - ANLIS "Dr. Carlos G. Malbrán"; Argentina 2023-02-01T00:00:00Z http://sgc.anlis.gob.ar/handle/123456789/2434 Title: The second coming of urban yellow fever in the Americas: looking the past to see the future Authors: Salomón, Oscar Daniel; Arias, Antonieta Rojas DE Abstract: Yellow fever (YF) epizootics in South America during the 21st century have an unprecedented recorded magnitude and geographical dispersion. The YF spread progressively involved areas considered previously free of risk reaching the edge of cities with large unvaccinated populations, and urban outbreaks were frequently forecasted. We critically reviewed the initial stages and enhancing contexts of YF urban epidemics since the 17th century in the Americas, and the modeling attempts of YF epidemic risk by of Aedes-Human transmission, to find common factors that increase the probability of these events in the current scenarios. The YF urban outbreaks of the past showed as necessary conditions the multiple introduction by viremic carriers clustered in time and space, coincident with population peaks of Aedes. These conditions are not met in the current outbreaks in the Americas by sylvatic YF cycles, besides the protective impact of vector control campaigns, vaccination coverage, improved surveillance, and case management. Therefore, urban Aedes-Human YF outbreaks in the Americas are still possible but with low probability or very focal transmission, while the conditions reported in the past were avoided, and the surveillance and control measures sustained, including the vaccination of the population at risk. Description: Fil. Salomón, Oscar Daniel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Medicina Tropical; Argentina. Comité Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.; Fil: Rojas De Arias, Antonieta. Centro para el Desarrollo de la Investigación Científica (CEDIC), Asunción, Paraguay. 2022-01-01T00:00:00Z