Helminths of small rodents (Heteromyidae and Cricetidae) in the Yucatan Peninsula, Mexico: an integrative taxonomic approach to their inventory

In this survey, we inventoried the helminths of heteromyid and cricetid rodents captured in the Yucatan Peninsula from 2017 to 2019. Helminths were identified using morphological techniques (clearing, staining, and scanning electron microscopy). Also, the 28S rRNA gene of individuals from several helminth taxa was successfully amplified and sequenced. To confirm the identification at the generic level, and in some cases at the specific level, and the genealogical relationships of the parasites, phylogenetic analyses were performed with the new 28S sequences. We identified 22 species of helminths including three trematodes (Brachylaimidae, Dicrocoeliidae, and Microphallidae), five cestodes (Davaineidae, Hymenolepididae, and Taeniidae), and 14 nematodes (Trichuridae, Ancylostomatidae, Ornithostrongylidae, Heligmonellidae, and Oxyuridae) from Heteromys gaumeri (Heteromyidae), Ototylomys phyllotis, Oligoryzomys fulvescens, Peromyscus yucatanicus, Sigmodon toltecus, and Reithrodontomys gracilis (Cricetidae). The overall frequency of infection in small rodents was 84.1% (143/170); all specimens of H. gaumeri, S. toltecus and Ol. fulvescens were infected with helminths. In total, we provided 46 new sequences of the 28S gene from 17 species of helminths. Seven species are likely undescribed species, six are reported for the first time in rodents from Mexico, and 12 are new host records in the Americas. Before this study, 87 taxa of helminths had been reported from 35 cricetid and 12 heteromyid species in 21 Mexican states. Our findings increase to 93 the helminth taxa in these rodents, and to 36 the cricetid species parasitized by helminths. This large scale-survey is the first to use an integrative approach to inventory the helminths of wild small rodents in Mexico.Fil: Panti May, Jesús Alonso. Universidad Autónoma de Yucatán;Fil: Moguel Chin, Wilson Isaias. Universidad Autónoma de Yucatán;Fil: Hernández Mena, David Iván. Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional; MéxicoFil: Cárdenas-Vargas, Miguel Humberto. Universidad Autónoma de Yucatán; MéxicoFil: Torres Castro, Marco. Universidad Autónoma de Yucatán;Fil: García Prieto, Luis. Universidad Nacional Autónoma de México; MéxicoFil: Digiani, Maria Celina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Hernández Betancourt, Silvia F.. Universidad Autónoma de Yucatán;Fil: Vidal Martínez, Víctor Manuel. Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional; Méxic

Altered TMPRSS2 usage by SARS-CoV-2 Omicron impacts infectivity and fusogenicity

The SARS-CoV-2 Omicron BA.1 variant emerged in 20211 and has multiple mutations in its spike protein2. Here we show that the spike protein of Omicron has a higher affinity for ACE2 compared with Delta, and a marked change in its antigenicity increases Omicron’s evasion of therapeutic monoclonal and vaccine-elicited polyclonal neutralizing antibodies after two doses. mRNA vaccination as a third vaccine dose rescues and broadens neutralization. Importantly, the antiviral drugs remdesivir and molnupiravir retain efficacy against Omicron BA.1. Replication was similar for Omicron and Delta virus isolates in human nasal epithelial cultures. However, in lung cells and gut cells, Omicron demonstrated lower replication. Omicron spike protein was less efficiently cleaved compared with Delta. The differences in replication were mapped to the entry efficiency of the virus on the basis of spike-pseudotyped virus assays. The defect in entry of Omicron pseudotyped virus to specific cell types effectively correlated with higher cellular RNA expression of TMPRSS2, and deletion of TMPRSS2 affected Delta entry to a greater extent than Omicron. Furthermore, drug inhibitors targeting specific entry pathways3 demonstrated that the Omicron spike inefficiently uses the cellular protease TMPRSS2, which promotes cell entry through plasma membrane fusion, with greater dependency on cell entry through the endocytic pathway. Consistent with suboptimal S1/S2 cleavage and inability to use TMPRSS2, syncytium formation by the Omicron spike was substantially impaired compared with the Delta spike. The less efficient spike cleavage of Omicron at S1/S2 is associated with a shift in cellular tropism away from TMPRSS2-expressing cells, with implications for altered pathogenesis

Biodiversidad 2014. Reporte de Estado y Tendencias de la Biodiversidad Continental de Colombia

Biodiversidad 2014 es el resultado de esfuerzos importantes de análisis científico, como también de coordinación nacional de información e inventario sobre la biodiversidad en Colombia y representa un adelanto en la manera de presentar datos sobre el estado de la biodiversidad, su localización y los factores de cambios, presentando escenarios posibles de sus tendencias futuras. Esto implica nuevos enfoques para la gestión ambiental, que puedan aportar nuevas formas de desarrollo que no impliquen la pérdida de las especies o los ecosistemas que habitan.Bogotá, D. C

The Social Anxiety Questionnaire for Children: Cross-Cultural Assessment with a New Self-Report Measure

This study describes a series of exploratory and confirmatory factor analyses that were conducted with the 44-item Social Anxiety Questionnaire for Children- 4th version (SAQ-CIV) to identify a reduced set of items that might be used to construct a new abbreviated instrument for measuring social anxiety in children and adolescents. The fourth version of the Social Anxiety Questionnaire for Children (SAQ-CIV) was administered to 12,801 non-clinical participants (ages 9 to 15 years) from 12 Latin American countries and Spain. Exploratory and confirmatory factor analysis supported a 6-factor structure of social anxiety in children, replicating a similar structure to that of adults (Caballo et al. in Behavioral Psychology/Psicología Conductual, 18(1), 5–34, 2010; Caballo et al. in Behavior Therapy, 43(2), 313–328, 2012): 1) Interactions with the opposite sex, 2) Criticism and embarrassment, 3) Speaking in public/Talking to teachers, 4) Assertive expression of annoyance and disgust, 5) Performing in public, and 6) Interactions with strangers. Each of the factors contains 4 items, yielding an abbreviated 24-item instrument, the Social Anxiety Questionnaire for Children (SAQ-C). The present results suggest this is a reliable, valid, and culturally sensitive instrument to assess social anxiety in youth