Catálogo de publicaciones - revistas

<jats:title>From bees to honey</jats:title> <jats:p> Neonicotinoid pesticides are applied globally. Concern about their impacts has been increasing as evidence for negative effects on bee health and persistence has accumulated. Mitchell <jats:italic>et al.</jats:italic> looked at the prevalence of these pesticides in honey from across the world and found traces in the majority of samples tested (see the Perspective by Connolly). The neonicotinoid compounds occurred at levels considered safe for human consumption, but the contamination confirms the inundation of bees and their environments with these pesticides, despite some recent efforts to decrease their use. </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" issue="6359" page="109" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan3684">109</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6359" page="38" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aao6000">38</jats:related-article> </jats:p>

<jats:title>Imaging the unforeseen fate of neutrophils</jats:title> <jats:p> Inflammation that results from insults such as ischemia and reperfusion or trauma in the absence of microorganisms is known as “sterile inflammation.” Neutrophils are recruited in vast numbers during sterile inflammation and have been thought to play a detrimental role. Wang <jats:italic>et al.</jats:italic> used intravital microscopy to show that neutrophils actually perform helpful tasks such as removing and regenerating thermally damaged blood vessels in the liver (see the Perspective by Garner and de Visser). Moreover, neutrophils neither die nor are phagocytosed. Instead, they return to the circulation in a process called “reverse transmigration,” making a pit stop in the lungs, before ending their lives where they began—in the bone marrow. Thus, a reconsideration of the use of anti-neutrophil therapies after injury may be warranted. </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" issue="6359" page="111" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aam9690">111</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6359" page="42" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aap8361">42</jats:related-article> </jats:p>

<jats:title>Elucidating pathological fibril structure</jats:title> <jats:p> Amyloid-β (Aβ) is a key pathological contributor to Alzheimer's disease. Gremer <jats:italic>et al.</jats:italic> used cryoelectron microscopy data to build a high-quality de novo atomic model of Aβ fibrils (see the Perspective by Pospich and Raunser). The complete structure reveals all 42 amino acids (including the entire N terminus) and provides a structural basis for understanding the effect of several disease-causing and disease-preventing mutations. The fibril consists of two intertwined protofilaments with an unexpected dimer interface that is different from those proposed previously. The structure has implications for the mechanism of fibril growth and will be an important stepping stone to rational drug design. </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" issue="6359" page="116" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aao2825">116</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6359" page="45" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aap8002">45</jats:related-article> </jats:p>

<jats:title>Gene expression during mitosis</jats:title> <jats:p> During mitosis, long-range interactions within chromosomes are lost, and many enhancers become inactive. It is generally thought that gene expression is silent at this time. However, transcription must be reactivated when cells reenter the cell cycle in order to maintain cell identity. Palozola <jats:italic>et al.</jats:italic> used a sensitive nascent RNA labeling and sequencing method to reveal low-level transcription of many genes in mitosis. Upon mitotic exit, the amplitude of gene expression was reestablished with basic cell functions prioritized over cell-specific genes. Thus, transcription itself may retain gene expression patterns through mitosis. </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" issue="6359" page="119" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aal4671">119</jats:related-article> </jats:p>

<jats:p> The vast majority of clinical samples are still archived using a decades-old technique of fixation with formaldehyde and embedding in paraffin wax to generate so-called formalin-fixed paraffin-embedded (FFPE) tissue blocks. This process of fixation and embedding, as well as long-term storage, can result in severe degradation of nucleic acids in the tissue. The fixation process itself causes cross-linkage between nucleic acids and proteins, as well as covalent modification of nucleic acids by monomethylol (-CH <jats:sub>2</jats:sub> OH) addition to the bases. Millions of FFPE blocks form the foundation of many tissue archives worldwide, and are essential to clinical research for exploring disease pathways and developing novel therapies. The inherent challenges of obtaining useable nucleic acids from difficult sample types such as these can be overcome by using the latest technologies and procedures to provide meaningful results throughout the next-generation sequencing workflow, from initial extraction of DNA/RNA to sample quantification, sample quality control, and library preparation. </jats:p>

<jats:p>A weekly roundup of information on newly offered instrumentation, apparatus, and laboratory materials of potential interest to researchers.</jats:p>