Search results for "virus"
showing 10 items of 5024 documents
Modification of face masks with zeolite imidazolate framework-8
2022
The worldwide spread of the SARS-CoV-2 virus has continued to accelerate, putting a considerable burden on public health, safety, and the global economy. Taking into consideration that the main route of virus transmission is via respiratory particles, the face mask represents a simple and efficient barrier between potentially infected and healthy individuals, thus reducing transmissibility per contact by reducing transmission of infected respiratory particles. However, long-term usage of a face mask leads to the accumulation of significant amounts of different pathogens and viruses onto the surface of the mask and can result in dangerous bacterial and viral co-infections. Zeolite imidazolat…
Aproximaciones moleculares al estudio de las interacciones de rotavirus y norovirus con el huésped
2020
Los norovirus humanos son los principales agentes etiológicos de gastroenteritis aguda en todo el mundo. Aunque los norovirus son muy diversos (se han detectado más de 30 genotipos en humanos), durante los últimos 40 años la mayoría de los brotes y epidemias han sido causados por cepas del genotipo GII.4, lo que plantea interrogantes sobre su persistencia en la población. Entre otras posibles explicaciones, se considera que la evasión inmunológica es la principal causa de su éxito. Para estudiar en detalle el reconocimiento y la evasión de anticuerpos, analizamos un epítopo conformacional reconocido por un anticuerpo monoclonal (3C3G3) mediante mutagénesis dirigida y resonancia superficial …
The Putative Metal Coordination Motif in the Endonuclease Domain of Human Parvovirus B19 NS1 Is Critical for NS1 Induced S Phase Arrest and DNA Damage
2011
The non-structural proteins (NS) of the parvovirus family are highly conserved multi-functional molecules that have been extensively characterized and shown to be integral to viral replication. Along with NTP-dependent helicase activity, these proteins carry within their sequences domains that allow them to bind DNA and act as nucleases in order to resolve the concatameric intermediates developed during viral replication. The parvovirus B19 NS1 protein contains sequence domains highly similar to those previously implicated in the above-described functions of NS proteins from adeno-associated virus (AAV), minute virus of mice (MVM) and other non-human parvoviruses. Previous studies have show…
Evolución de virus en huéspedes con susceptibilidad variable: consecuencias en eficacia y virulencia
2020
Los virus de RNA se encuentran entre los patógenos emergentes más abundantes. Durante su ciclo de vida normal, los virus se mueven de un huésped a otro, a veces transmitidos por el aire o el agua, pero a veces utilizando vectores en los que también pueden replicarse. Dentro de un huésped individual, los virus se enfrentan a múltiples tejidos y tipos de células que difieren en propiedades fisiológicas y bioquímicas y son constantemente desafiados por una variedad de respuestas inmunes antivirales. Para maximizar su fitness, los virus deben adaptarse necesariamente a todos estos factores. En la mayoría de los casos, esta adaptación se produce fácilmente debido a su enorme potencial evolutivo.…
Non-structural proteins P17 and P33 are involved in the assembly of the internal membrane-containing virus PRD1.
2015
AbstractBacteriophage PRD1, which has been studied intensively at the structural and functional levels, still has some gene products with unknown functions and certain aspects of the PRD1 assembly process have remained unsolved. In this study, we demonstrate that the phage-encoded non-structural proteins P17 and P33, either individually or together, complement the defect in a temperature-sensitive GroES mutant of Escherichia coli for host growth and PRD1 propagation. Confocal microscopy of fluorescent fusion proteins revealed co-localisation between P33 and P17 as well as between P33 and the host chaperonin GroEL. A fluorescence recovery after photobleaching assay demonstrated that the diff…
Epstein-Barr virus infection as a trigger of autoimmune hepatitis: Case report
2008
Abstract: The study underlines the importance of the differential diagnosis between primary Epstein- Barr virus EBV associated hepatitis with features of autoimmunity, in which there is a direct pathogenetic role of the virus, and EBV related autoimmune hepatitis, in which EBV could act as the trigger of the immune-mediated damage with probable differences between the two conditions with regard to the prognosis and the responsiveness to immunosuppressive treatment. Moreover we hypothesise that the favourable outcome in our patient, better than the most of autoimmune hepatitis cases, may be related either to the moderate necroinflammatory activity and to the low level of fibrosis at the begi…
Learning Design for Future Higher Education – Insights From the Time of COVID-19
2021
The COVID-19 pandemic brought many challenges in higher education. All teaching and learning activities were moved online. Universities had to provide adapted solutions to facilitate learning and maintain students’ engagement. Online education implies creating new learning environments with the help of digital technologies. Beyond the process of acquisition of knowledge, teachers needed to facilitate cooperative learning, build positive relations, and reduce negative emotions. We provide some expert insights based on empirical observations on teaching and assessment practices connected with psychology models applied in education. The aim of the paper is to formulate specific learning design…
Identification of a ligand on the Wip1 bacteriophage highly specific for a receptor on B. anthracis.
2013
Tectiviridae is a family of tailless bacteriophages with Gram-negative and Gram-positive hosts. The family model PRD1 and its close relatives all infect a broad range of enterobacteria by recognizing a plasmid-encoded conjugal transfer complex as a receptor. In contrast, tectiviruses with Gram-positive hosts are highly specific to only a few hosts within the same bacterial species. The cellular determinants that account for the observed specificity remain unknown. Here we present the genome sequence of Wip1, a tectivirus that infects the pathogen Bacillus anthracis. The Wip1 genome is related to other tectiviruses with Gram-positive hosts, notably, AP50, but displays some interesting differ…
Cooperation between Different CRISPR-Cas Types Enables Adaptation in an RNA-Targeting System
2021
CRISPR-Cas systems are immune systems that protect bacteria and archaea against their viruses, bacteriophages. Immunity is achieved through the acquisition of short DNA fragments from the viral invader’s genome.
Bracovirus derived genes in the genome of Spodoptera exigua Hubner (Lepidoptera: Noctuidae) and their role in host susceptibility to pathogens
2015
La asociación entre los himenópteros parasitoides, polydnavirus (PDV) y lepidópteros representa un modelo interesante para estudiar la transferencia horizontal de genes. Está bien documentado que miles de himenópteros parasitoides pertenecientes a las familias Braconidae e Ichneumonidae han domesticado virus simbióticos denominados respectivamente Bracovirus o Ichnovirus. El virus se inyecta junto con los huevos del parásito en el hemocele del lepidóptero huésped, donde se expresan proteínas específicas. Estas proteínas inhiben el sistema inmune del lepidóptero y detienen su desarrollo, lo que beneficia el desarrollo de los huevos y luego las larvas del parasitoide. En este sistema único, t…