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Genetic diversity of Mycoplasma bovis isolated from bovine respiratory disease and bovine mastitis in Chile
(2025) Goddard, Matías; San Martín, Joscelyn; Molina Mora, José Arturo; Collado, Luis; Rodriguez, Jaime; Galarce Galvez, Nicolas Elias; Mella Nettig, Armin Fabián
Mycoplasma bovis, a major bacterial pathogen for cattle, is responsible for diseases such as pneumonia, mastitis, otitis, and arthritis, leading to substantial economic losses and animal welfare concerns. Despite its wide global distribution, there is limited information in South America. M. bovis has been reported as a mastitis agent in Chile, but its genetic diversity is poorly understood. Therefore, this study aimed to determine the genetic diversity of M. bovis isolates from Chilean dairy cattle (from bovine respiratory disease and mastitis cases) in the last two decades and evaluate their genetic relatedness with strains isolated in different countries using a whole genome sequencing approach. The M. bovis population in Chile was found to be highly homogeneous, with MLST and phylogenomic analysis identifying ST60 as the dominant clone, representing most of the isolates (97.8 %), while just one isolate was typed as ST12 (2.2 %). Phylogenomic analysis revealed close genetic relatedness among most Chilean isolates, showing a close genetic relationship with North American strains, forming a tight clade with Canadian ST60 strains, while the single Chilean ST12 isolate clustered with North American, Israeli, and European strains and clustered with the type strain (PG45) of this species. Moreover, the pangenome analysis confirms that M. bovis has an open pangenome, with a large range of accessory genes that remain largely unexplored and may hold key insights into its genome plasticity, thereby opening future research. The findings of this study provide the first insights into the Chilean population structure of M. bovis, contributing to the global epidemiology of this pathogen with a focus on South America. These results also open future research focused on the comprehensive characterization of this dominant clone, inspiring the scientific community to further exploration into the genetic diversity of M. bovis in Chile.
De novo assembly of a chromosome-level reference genome of the ornamental butterfly Sericinus montelus based on nanopore sequencing and Hi-C analysis
(2023-03-08) Li, Jingjing; Wang, Haiyan; Zhu, Jianqing; Yang, Qi; Luan, Yang; Shi, Leming; Molina Mora, José Arturo; Zheng, Yuanting
Sericinus montelus (Lepidoptera, Papilionidae, Parnassiinae) is a high-value ornamental swallowtail butterfly species widely distributed in Northern and Central China, Japan, Korea, and Russia. The larval stage of this species feeds exclusively on Aristolochia plants. The Aristolochia species is well known for its high levels of aristolochic acids (AAs), which have been found to be carcinogenic for numerous animals. The swallowtail butterfly is among the few that can feed on these toxic host plants. However, the genetic adaptation of S. montelus to confer new abilities for AA tolerance has not yet been well explored, largely due to the limited genomic resources of this species. This study aimed to present a chromosome-level reference genome for S. montelus using the Oxford Nanopore long-read sequencing, Illumina short-read sequencing, and Hi-C technology. The final assembly was composed of 581.44 Mb with an expected genome size of 619.27 Mb. Further, 99.98% of the bases could be anchored onto 30 chromosomes. The N50 of contigs and scaffolds was 5.74 and 19.12 Mb, respectively. Approximately 48.86% of the assembled genome was suggested to be repeat elements, and 13,720 protein-coding genes were predicted in the current assembly. The phylogenetic analysis indicated that S. montelus diverged from the common ancestor of swallowtails about 58.57–80.46 million years ago. Compared with related species, S. montelus showed a significant expansion of P450 gene family members, and positive selections on eloa, heatr1, and aph1a resulted in the AA tolerance for S. montelus larva. The de novo assembly of a high-quality reference genome for S. montelus provided a fundamental genomic tool for future research on evolution, genome genetics, and toxicology of the swallowtail butterflies.
Capítulo 3. Cruzar las fronteras con el celular: desigualdades, apropiación tecnológica y resistencias en la migración centroamericana
(2025) Ferris Dobles, Michele Francis
Las migraciones latinoamericanas y caribeñas han dejado de ser un fenómeno unidireccional hacia Estados Unidos para convertirse en una experiencia global, compleja y multiescalar, vinculada con crisis contemporáneas que se refuerzan entre sí: desigualdades, cambio climático, conflictos, pandemias y transformaciones tecnológicas. Este libro explora las causas, implicaciones y tensiones de estas movilidades, considerando los factores estructurales, institucionales, ambientales y culturales que las atraviesan, así como sus dimensiones de género, etnia y clase. Las migraciones no son solo desplazamientos de personas, sino también de ideas, saberes y culturas, transformando tanto a quienes migran como a las sociedades que los reciben. Con una mirada histórica y relacional, esta obra ofrece al lector una comprensión integral de la migración como fenómeno vital en la construcción de ciudadanía, justicia social y futuros posibles en América Latina y el Caribe.
Chapter 209 - Bothrops asper Metalloproteinase BaP1
(2013) Gutiérrez, José María; Rucavado Romero, Alexandra; Escalante Muñoz, Teresa; Rawlings, Neil D.; Salvesen, Guy
BaP1 is a class P-I hemorrhagic metalloproteinase isolated from the venom of Bothrops asper, a species responsible for most snakebite envenomations in Central America. This 22.7 kDa enzyme contains the catalytic motif HEXXHXXGXXH, characteristic of metzincins, and exhibits high affinity for extracellular matrix proteins such as type IV collagen, fibronectin, laminin, and fibrinogen. Its proteolytic activity weakens the capillary basement membrane, causing hemorrhage, muscle necrosis, edema, and local inflammation. The hemorrhagic mechanism of BaP1 involves the degradation of vascular components followed by capillary rupture due to hemodynamic forces. Additionally, BaP1 promotes complement activation and the release of proinflammatory cytokines, contributing to pain and local tissue damage. BaP1 is considered a key biological model for understanding the mechanisms of action of viperid snake venom metalloproteinases and for the development of adjunct therapies to conventional antivenom treatment.
Mass movements dynamics and morphologies in Costa Rica
(2024-10-04) Quesada Román, Adolfo
Landslides are natural processes that commonly affect human activities at every latitude and altitude worldwide. Tropical countries such as Costa Rica deal annually with landslides affecting public and privateinfrastructure and activities. This chapter provides a brief overview of landslide origin, dynamics, and morphologies applicable to Costa Rica. Coseismic and hydrometeorological dynamics are common landslide triggers, but land use changes are also important. Large landslides are related with volcanic slopes and densely vegetated rural contexts, while smaller but more common mass movements are linked with periurban conditions, especially in densely populated areas with altered land use. On average, during the last five decades every year, 80 landslide events occurred in Costa Rica, causing 5 people died, 9 houses destroyed, and approximately, 1 million US dollars of losses. This chapter suggests more tudies dealing with modelling, geomorphological characterization, early warning systems, and continued monitoring of landslides on susceptible sites in Costa Rica.