HIV-1 particles incorporate various host transmembrane proteins in addition to viral Env glycoprotein during assembly at the plasma membrane. In polarized T cells, HIV-1 structural protein Gag localizes to the plasma membrane of uropod, a rear-end protrusion. Notably, uropod transmembrane proteins PSGL-1 and CD43 cocluster specifically with Gag assembling at the plasma membrane even in cells that do not form uropods. Recent reports have shown that expression of either PSGL-1 or CD43 in virus-producing cells reduces the infectivity of progeny virions and that HIV-1 infection reduces the cell surface expression of these proteins. However, the mechanisms for both processes remain to be determined. In this study, we found that virion incorporation of PSGL-1 and CD43 closely correlates with diminished virion infectivity. PSGL-1 and CD43 inhibited virus attachment to CD4+cells irrespective of the presence of Env. These proteins also inhibited virion attachment to CD4−lymphoid organ fibroblastic reticular cells that mediate transinfection of CD4+T cells. Consistent with the possibility that highly extended extracellular domains of these proteins physically block virus–cell attachment, the inhibitory effect of PSGL-1 required its full-length ectodomain. HIV-1 encoding Gag mutants that are defective in either coclustering with these host proteins or ESCRT-dependent particle release failed to reduce PSGL-1 on surface of infected cells. This study reveals an anti–HIV-1 mechanism that suppresses virus–cell attachment and a previously unappreciated process of HIV-1-mediated down-regulation of host antiviral proteins, both of which likely require virion incorporation of these proteins.

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The Healthy Air, Healthy Schools Study was established to better understand the impact of ultrafine particles (UFPs) on indoor air quality in communities surrounding Seattle-Tacoma (Sea-Tac) International Airport. The study team took multipollutant measurements of indoor and outdoor air pollution at five participating school locations to estimate infiltration indoors. The schools participating in this project were located within a 7-mile radius of Sea-Tac International Airport and within 0.5 mile of an active flight path. Based on experimental measures in an unoccupied classroom, infiltration rates of a) UFPs of aircraft origin, b) UFPs of traffic origin, and c) wildfire smoke or other outdoor pollutants were characterized before and after the introduction of a portable high-efficiency particulate air (HEPA) filter intervention. The portable HEPA cleaners were an effective short-term intervention to improve the air quality in classroom environments, reducing the UFP count concentration from one-half to approximately one-tenth of that measured outside. This study is unique in focusing on UFPs in schools and demonstrating that UFPs measured in classroom spaces are primarily of outdoor origin. Although existing research suggests that reducing particulate matter in homes can significantly improve asthma outcomes, further investigation is necessary to establish the benefits to student health and academic performance of reducing UFP exposures in schools.

Educación laica, gratuita, obligatoria, integral, científica, democrática, nacionalista y de calidad, como valores para la educación pública que se han incorporado y evolucionado a través del tiempo, han dado sentido y orientación a la acción gubernamental durante gran parte del siglo que ha cumplido la Constitución mexicana de 1917; sin embargo, parecen aún lejanos e insuficientes para configurar el proyecto educativo del México futuro. Por ello, el debate sobre el derecho a la educación, si bien tiene varias décadas de estar presente entre especialistas y académicos, parece más pertinente hoy, frente a las dificultades y controversias que ha enfrentado la reforma educativa de 2013. El centenario del Artículo Tercero Constitucional es un marco simbólico que brinda la oportunidad de compendiar el estado actual de su debate, mismo que se ha logrado gracias a la colaboración entre la Universidad Pedagógica Nacional, la Facultad Latinoamericana de Ciencias Sociales-México (flacso) y la Comisión de Educación del Senado de la República lxiii Legislatura, que además abre la posibilidad para la reflexión permanente sobre los retos que deberá enfrentar, en los años venideros, este importante derecho humano. Para hacer un justo reflejo del debate nacional, la pluralidad se planteó como uno de los principales objetivos de esta obra. Las contribuciones que se encuentran incluidas fueron desarrolladas por sus autores, en respuesta a una convocatoria de la Universidad Pedagógica Nacional y la Comisión de Educación del Senado de la República lxiii Legislatura, buscando que todo interesado en el tema que tuviera algo que aportar al debate pudiese hacerlo, siempre en un marco de tolerancia al derecho de otros de disentir, condición que los autores participantes mostraron en un elevado ejemplo de capacidad de diálogo y debate entre pares, donde las posturas totalizantes cedieron el paso a la crítica reflexiva.