Catálogo de publicaciones - revistas

<jats:title>Phase separation can be skin deep</jats:title> <jats:p> The skin's barrier arises from proliferative cells that generate a perpetual upward flux of terminally differentiating epidermal cells. Cells nearing the body surface suddenly lose their organelles, becoming dead cellular ghosts called squames. Working in mouse tissue, Garcia Quiroz <jats:italic>et al.</jats:italic> found that as differentiation-specific proteins accumulate in the keratinocytes, they undergo a vinegar-in-oil type of phase separation that crowds the cytoplasm with increasingly viscous protein droplets (see the Perspective by Rai and Pelkmans). Upon approaching the acidic skin surface, the environmentally sensitive liquid-like droplets respond and dissipate, driving squame formation. These dynamics come into play in human skin barrier diseases, where mutations cause maladapted liquid-phase transitions. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.aax9554">eaax9554</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6483" page="1193" related-article-type="in-this-issue" vol="367" xlink:href="10.1126/science.abb0060">1193</jats:related-article> </jats:p>

<jats:title>Spreading edema after stroke</jats:title> <jats:p> The brain is enveloped in a cushion of cerebrospinal fluid (CSF), which normally provides protection and helps to remove metabolic waste. CSF transport has also recently been shown to play unexpected roles in neurodegeneration and sleep. Mestre <jats:italic>et al.</jats:italic> used multimodal in vivo imaging in rodents and found that, after a stroke, an abnormally large volume of CSF rushes into the brain, causing swelling (see the Perspective by Moss and Williams). This influx of CSF is caused by constrictions of arteries triggered by a well-known propagating chemical reaction-diffusion wave called spreading depolarization. CSF transport can thus play a role in brain swelling after stroke. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.aax7171">eaax7171</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6483" page="1195" related-article-type="in-this-issue" vol="367" xlink:href="10.1126/science.aba8801">1195</jats:related-article> </jats:p>

<jats:title>Ammonium salts on comet 67P</jats:title> <jats:p> The distribution of carbon and nitrogen in the Solar System is thought to reflect the stability of carbon- and nitrogen-bearing molecules when exposed to the heat of the forming Sun. Comets have a low nitrogen-to-carbon ratio, which is contrary to expectations because they originate in the outer Solar System where nitrogen species should be common. Poch <jats:italic>et al.</jats:italic> used laboratory experiments to simulate cometary surfaces and compared the resulting spectra with comet 67P/Churyumov-Gerasimenko. They assigned a previously unidentified infrared absorption band to nitrogen-containing ammonium salts. The salts could contain enough nitrogen to bring the comet's nitrogen-to-carbon ratio in line with the Sun's. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.aaw7462">eaaw7462</jats:related-article> </jats:p>

<jats:p>“Do me a favor, speed it up, speed it up.” This is what U.S. President Donald Trump told the National Association of Counties Legislative Conference, recounting what he said to pharmaceutical executives about the progress toward a vaccine for severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19). Anthony Fauci, the long-time leader of the National Institute of Allergy and Infectious Diseases, has been telling the president repeatedly that developing the vaccine will take at least a year and a half—the same message conveyed by pharmaceutical executives. Apparently, Trump thought that simply repeating his request would change the outcome.</jats:p>

<jats:p>A roundup of weekly science policy and related news.</jats:p>