RESUMO
Anelloviruses are nonpathogenic viruses that comprise a major portion of the human virome. Despite being ubiquitous in the human population, anelloviruses (ANVs) remain poorly understood. Basic features of the virus, such as the identity of its capsid protein and the structure of the viral particle, have been unclear until now. Here, we use cryogenic electron microscopy to describe the first structure of an ANV-like particle. The particle, formed by 60 jelly roll domain-containing ANV capsid proteins, forms an icosahedral particle core from which spike domains extend to form a salient part of the particle surface. The spike domains come together around the 5-fold symmetry axis to form crown-like features. The base of the spike domain, the P1 subdomain, shares some sequence conservation between ANV strains while a hypervariable region, forming the P2 subdomain, is at the spike domain apex. We propose that this structure renders the particle less susceptible to antibody neutralization by hiding vulnerable conserved domains while exposing highly diverse epitopes as immunological decoys, thereby contributing to the immune evasion properties of anelloviruses. These results shed light on the structure of anelloviruses and provide a framework to understand their interactions with the immune system.
Assuntos
Proteínas do Capsídeo , Microscopia Crioeletrônica , Evasão da Resposta Imune , Vírion , Proteínas do Capsídeo/química , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/ultraestrutura , Vírion/ultraestrutura , Vírion/imunologia , Humanos , Anelloviridae/genética , Anelloviridae/imunologia , Modelos Moleculares , Domínios Proteicos , Epitopos/imunologia , Epitopos/química , Sequência de AminoácidosRESUMO
Siendo la patologia tiroidea , relativamente frecuente, no se han establecido pautas claramente definidas para el manejo de los nodulostiroideos, el objetivo principal de este trabajo es pretender hacer un resumen de la conducta a seguir actualmente con los nodulos tiroideos. En el hospital Seton de la Caja Petrolera de salud de la ciudad de Cochabamba-Bolivia, fueron revisadas 124 historias clinicas de pacientes operados por patologia tiroidea (cuadro 1) en un periodo de 17 anos (1979/1995), con 108 mujeres (87,1 por ciento) y 16 varones (12,9 por ciento); todos los casos con estudios paraclinicos completos, ademas de las biopsias trans operatorias. Recientemente introducimos la citologia por puncion con aguja fina; 112 pacientes (90,4 por ciento) fueron operados por patologia benigna con buena evolucion postoperatoria y sin mortalidad; 12 pacientes (9,6 por ciento) por cancer con 2 obitos en postoperatorio mediato.