Catálogo de publicaciones - revistas

<jats:title>Boosterism could save lives</jats:title> <jats:p> Postinfection immune protection against severe acute respiratory syndrome coronavirus 2 reinfection is not fully understood. It will be devastating if waves of new variants emerge that undermine natural immune protection. Stamatatos <jats:italic>et al.</jats:italic> investigated immune responsiveness 4 to 8 months after previously infected individuals were given a messenger RNA–based vaccine developed for the original Wuhan variant (see the Perspective by Crotty). Before vaccination, postinfection serum antibody neutralization responses to virus variants were variable and weak. Vaccination elevated postinfection serum-neutralizing capacity approximately 1000-fold against Wuhan-Hu-1 and other strains, and serum neutralization against the variant B.1.351 was enhanced. Although responses were relatively muted against the variant, they still showed characteristic memory responses. Vaccination with the Wuhan-Hu-1 variant may thus offer a valuable boost to protective responses against subsequent infection with variant viruses. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , abg9175, this issue p. <jats:related-article issue="6549" page="1413" related-article-type="in-this-issue" vol="372">1413</jats:related-article> ; see also abj2258, p. <jats:related-article issue="6549" page="1392" related-article-type="in-this-issue" vol="372">1392</jats:related-article> </jats:p>

<jats:title>A boost from infection</jats:title> <jats:p> During clinical trials of severe acute respiratory syndrome coronavirus 2 vaccines, no one who had survived infection with the virus was tested. A year after the pandemic was declared, vaccination of previously infected persons is a reality. Reynolds <jats:italic>et al.</jats:italic> address the knowledge gap in a cohort of UK health care workers given the Pfizer/BioNTech vaccine in which half of the participants had experienced natural virus infections early in the pandemic (see the Perspective by Crotty). Genotyping indicated that a genetic component underlies heterogeneity in immune responses to vaccine and to natural infection. After vaccination, naïve individuals developed antibody responses similar to those seen in naturally infected persons, but T cell responses were more limited and sometimes absent. However, antibody and memory responses in individuals vaccinated after infection were substantially boosted to the extent that a single vaccine dose is likely to protect against the more aggressive B.1.1.7 variant. It is possible that the messenger RNA vaccine has an adjuvant effect, biasing responses toward antibody generation. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , abh1282, this issue p. <jats:related-article issue="6549" page="1418" related-article-type="in-this-issue" vol="372">1418</jats:related-article> ; see also abj2258, p. <jats:related-article issue="6549" page="1392" related-article-type="in-this-issue" vol="372">1392</jats:related-article> </jats:p>

<jats:title> Middle Pleistocene <jats:italic>Homo</jats:italic> in the Levant </jats:title> <jats:p> Our understanding of the origin, distribution, and evolution of early humans and their close relatives has been greatly refined by recent new information. Adding to this trend, Hershkovitz <jats:italic>et al.</jats:italic> have uncovered evidence of a previously unknown archaic <jats:italic>Homo</jats:italic> population, the “Nesher Ramla <jats:italic>Homo</jats:italic> ” (see the Perspective by Mirazon Lahr). The authors present comprehensive qualitative and quantitative analyses of fossilized remains from a site in Israel dated to 140,000 to 120,000 years ago indicating the presence of a previously unrecognized group of hominins representing the last surviving populations of Middle Pleistocene <jats:italic>Homo</jats:italic> in Europe, southwest Asia, and Africa. In a companion paper, Zaidner <jats:italic>et al.</jats:italic> present the radiometric ages, stone tool assemblages, faunal assemblages, and other behavioral and environmental data associated with these fossils. This evidence shows that these hominins had fully mastered technology that until only recently was linked to either <jats:italic>Homo sapiens</jats:italic> or Neanderthals. Nesher Ramla <jats:italic>Homo</jats:italic> was an efficient hunter of large and small game, used wood for fuel, cooked or roasted meat, and maintained fires. These findings provide archaeological support for cultural interactions between different human lineages during the Middle Paleolithic, suggesting that admixture between Middle Pleistocene <jats:italic>Homo</jats:italic> and <jats:italic>H. sapiens</jats:italic> had already occurred by this time. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , abh3169 and abh3020, this issue p. <jats:related-article issue="6549" page="1424" related-article-type="in-this-issue" vol="372">1424</jats:related-article> and p. <jats:related-article issue="6549" page="1429" related-article-type="in-this-issue" vol="372">1429</jats:related-article> ; see also abj3077, p. <jats:related-article issue="6549" page="1395" related-article-type="in-this-issue" vol="372">1395</jats:related-article> </jats:p>

<jats:title> Middle Pleistocene <jats:italic>Homo</jats:italic> in the Levant </jats:title> <jats:p> Our understanding of the origin, distribution, and evolution of early humans and their close relatives has been greatly refined by recent new information. Adding to this trend, Hershkovitz <jats:italic>et al.</jats:italic> have uncovered evidence of a previously unknown archaic <jats:italic>Homo</jats:italic> population, the “Nesher Ramla <jats:italic>Homo</jats:italic> ” (see the Perspective by Mirazon Lahr). The authors present comprehensive qualitative and quantitative analyses of fossilized remains from a site in Israel dated to 140,000 to 120,000 years ago indicating the presence of a previously unrecognized group of hominins representing the last surviving populations of Middle Pleistocene <jats:italic>Homo</jats:italic> in Europe, southwest Asia, and Africa. In a companion paper, Zaidner <jats:italic>et al.</jats:italic> present the radiometric ages, stone tool assemblages, faunal assemblages, and other behavioral and environmental data associated with these fossils. This evidence shows that these hominins had fully mastered technology that until only recently was linked to either <jats:italic>Homo sapiens</jats:italic> or Neanderthals. Nesher Ramla <jats:italic>Homo</jats:italic> was an efficient hunter of large and small game, used wood for fuel, cooked or roasted meat, and maintained fires. These findings provide archaeological support for cultural interactions between different human lineages during the Middle Paleolithic, suggesting that admixture between Middle Pleistocene <jats:italic>Homo</jats:italic> and <jats:italic>H. sapiens</jats:italic> had already occurred by this time. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , abh3169 and abh3020, this issue p. <jats:related-article issue="6549" page="1424" related-article-type="in-this-issue" vol="372">1424</jats:related-article> and p. <jats:related-article issue="6549" page="1429" related-article-type="in-this-issue" vol="372">1429</jats:related-article> ; see also abj3077, p. <jats:related-article issue="6549" page="1395" related-article-type="in-this-issue" vol="372">1395</jats:related-article> </jats:p>

<jats:title>Methyl readers that repress transcription</jats:title> <jats:p> DNA methylation is a conserved epigenetic mark required for gene silencing in many different organisms. However, how the methyl mark is able to silence genes is still largely unknown. Ichino <jats:italic>et al.</jats:italic> discovered two <jats:italic>Arabidopsis</jats:italic> proteins named MBD5 and MBD6 that are recruited to DNA by direct recognition of methylation. These methyl readers recruit the class C J-domain protein SILENZIO to chromatin to silence methylated genes and transposons. SILENZIO likely acts through its interaction with heat shock chaperone proteins. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , abg6130, this issue p. <jats:related-article issue="6549" page="1434" related-article-type="in-this-issue" vol="372">1434</jats:related-article> </jats:p>

<jats:title>Masking out air sharing</jats:title> <jats:p> The effectiveness of masks in preventing the transmission of severe acute respiratory syndrome coronavirus 2 has been debated since the beginning of the COVID-19 pandemic. One important question is whether masks are effective despite the forceful expulsion of respiratory matter during coughing and sneezing. Cheng <jats:italic>et al.</jats:italic> convincingly show that most people live in conditions in which the airborne virus load is low. The probability of infection changes nonlinearly with the amount of respiratory matter to which a person is exposed. If most people in the wider community wear even simple surgical masks, then the probability of an encounter with a virus particle is even further limited. In indoor settings, it is impossible to avoid breathing in air that someone else has exhaled, and in hospital situations where the virus concentration is the highest, even the best-performing masks used without other protective gear such as hazmat suits will not provide adequate protection. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , abg6296, this issue p. <jats:related-article issue="6549" page="1439" related-article-type="in-this-issue" vol="372">1439</jats:related-article> </jats:p>

<jats:title>Rhodium atoms for alkane dehydrogenation</jats:title> <jats:p> Nanoparticles of rhodium dispersed on metal oxides are generally poor catalysts for alkane dehydrogenation because the reactants bind too strongly to the metal. Hannagan <jats:italic>et al.</jats:italic> performed first-principle calculations indicating that single rhodium atoms in a copper surface should be stable and selective for conversion of propane to propene and hydrogen. Model studies of single rhodium atoms embedded in a copper (111) surface revealed a very high selectivity to propene and high resistance to the formation of surface carbon that would deactivate the catalyst. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , abg8389, this issue p. <jats:related-article issue="6549" page="1444" related-article-type="in-this-issue" vol="372">1444</jats:related-article> </jats:p>