Communities in DSpace
Select a community to browse its collections.
Recent Submissions
Longitudinal metabolomics and lipidomics analyses reveal alterations associated with envenoming by Bothrops asper and Daboia russelii in an experimental murine model
(2022-09-23) Wase, Nishikant; Gutiérrez, José María; Rucavado Romero, Alexandra; Fox, Jay W.
Longitudinal metabolomics and lipidomics analyses were carried out on the blood plasma of mice injected intramuscularly with venoms of the viperid species Bothrops asper or Daboia russelii. Blood samples were collected 1, 3, 6, and 24 h after venom injection, and a control group of non-envenomed mice was included. Significant perturbations in metabolomics and lipidomics were observed at 1, 3, and 6 h, while values returned close to those of control mice by 24 h, hence reflecting a transient pattern of metabolic disturbance. Both venoms induced significant changes in amino acids, as well as in several purines and pyrimidines, and in some metabolites of the tricarboxylic acid cycle. KEGG analysis of metabolic pathways that showed those with the greatest change included aminoacyl tRNA synthesis and amino acid biosynthesis and metabolism pathways. With regard to lipid metabolism, there was an increase in triglycerides and some acyl carnitines and a concomitant drop in the levels of some phospholipids. In addition, envenomed mice had higher levels of cortisol, heme, and some oxidative stress markers. The overall pattern of metabolic changes in envenomed mice bears similarities with the patterns described in several traumatic injuries, thus underscoring a metabolic response/adaptation to the injurious action of the venoms.
Why is skeletal muscle regeneration impaired after myonecrosis induced by viperid snake venoms?
(2018-05-01) Gutiérrez, José María; Escalante Muñoz, Teresa; Hernández, Rosario; Gastaldello, Stefano; Saravia Otten, Ingrid Patricia; Rucavado Romero, Alexandra
Skeletal muscle regeneration after myonecrosis involves the activation, proliferation and fusion of myogenic cells, and a coordinated inflammatory response encompassing phagocytosis of necrotic cell debris, and the concerted synthesis of cytokines and growth factors. Myonecrosis often occurs in snakebite envenomings. In the case of venoms that cause myotoxicity without affecting the vasculature, such as those of many elapid snakes, regeneration proceeds successfully. In contrast, in envenomings by most viperid snakes, which affect the vasculature and extracellular matrix in addition to muscle fibers, regeneration is largely impaired and, therefore, the muscle mass is reduced and replaced by fibro-adipose tissue. This review discusses possible causes for such poor regenerative outcome including: (a) damage to muscle microvasculature, which causes tissue hypoxia and affects the inflammatory response and the timely removal of necrotic tissue; (b) damage to intramuscular nerves, which results in atrophy of regenerating fibers; (c) degradation of muscle cell basement membrane, compromising the spatial niche for proliferating myoblasts; (d) widespread degradation of the extracellular matrix; and (e) persistence of venom components in the damaged tissue, which may affect myogenic cells at critical points in the regenerative process. Understanding the causes of poor muscle regeneration may pave the way for the development of novel therapeutic interventions aimed at fostering the regenerative process in envenomed patients.
Crystallization and preliminary diffraction data of BaP1, a haemorrhagic metalloproteinase from Bothrops asper snake venom
(2002) Watanabe, Leandra; Rucavado Romero, Alexandra; Kamiguti, Aura S.; Theakston, R. David G.; Gutiérrez, José María; Arni, Rughuvir K.
BaP1 is a metalloproteinase isolated from the venom of the Central American snake Bothrops asper (terciopelo). It is a 24 kDa protein consisting of a single chain which includes the metalloproteinase domain only, therefore being classified as a class P-I snake-venom metalloproteinase. BaP1 induces prominent local tissue damage, such as haemorrhage, myonecrosis, blistering, dermonecrosis and oedema. In order to elucidate its structure, BaP1 was crystallized by the hanging-drop vapour-diffusion technique in 0.1 M bicine pH 9.0, 10% PEG 20 000 and 2%(v/v) dioxane. Diffraction data were observed to a resolution of 2.7 Å. Crystals belong to space group P212121, with unit-cell parameters a = 38.22, b = 60.17, c = 86.09 Å.
Towards Building a Latin American Community on Integrated and End-of-Life Care
(2025) IFIC LatAm; Collado, Claudia; Pinto, Paula; Vacarezza Suazo, Cristóbal; Sáenz Madrigal, María del Rocío; Gómez Duarte, Ingrid; Sancho Rojas, Wilmer; Quesada Chaves, Jossel; López Vargas, Wendy; Solis Calvo, Luis Fernando
The presentation outlines the development of a Latin American Community of Practice focused on integrated care and end-of-life support, grounded in the open table philosophy. This space aims to connect diverse forms of knowledge, promote collaborative work among professionals, communities, and institutions, and strengthen regional networks. Key principles include community engagement, cultural relevance, shared governance, and knowledge exchange, with the goal of building collective capacities and context-sensitive experiences across the region.
Ancestrally reconstructed Von Willebrand factor reveals evidence for trench warfare coevolution between opossums and pit vipers
(2022-06-20) Drabeck, Danielle H.; Rucavado Romero, Alexandra; Hingst Zaher, Erika; Dean, Antony; Jansa, Sharon A.
Opossums in the tribe Didelphini are resistant to pit viper venoms and are hypothesized to be coevolving with venomous snakes. Specifically, a protein involved in blood clotting (von Willebrand factor [vWF] which is targeted by snake venom C-type lectins [CTLs]) has been found to undergo rapid adaptive evolution in Didelphini. Several unique amino acid changes in vWF could explain their resistance; however, experimental evidence that these changes disrupt binding to venom CTLs was lacking. Furthermore, without explicit testing of ancestral phenotypes to reveal the mode of evolution, the assertion that this system represents an example of coevolution rather than noncoevolutionary adaptation remains unsupported. Using expressed vWF proteins and purified venom CTLs, we quantified binding affinity for vWF proteins from all resistant taxa, their venom-sensitive relatives, and their ancestors. We show that CTL-resistant vWF is present in opossums outside clade Didelphini and likely across a wider swath of opossums (family Didelphidae) than previously thought. Ancestral reconstruction and in vitro testing of vWF phenotypes in a clade of rapidly evolving opossums reveal a pattern consistent with trench warfare coevolution between opossums and their venomous snake prey.