Editors' Choice

Science  27 Apr 2018:
Vol. 360, Issue 6387, pp. 394
  1. Neurodevelopment

    The brain as a work in progress

    1. Pamela J. Hines

    Cognitive skills, such as those relating to executive function and coordination, continue to develop into adulthood.

    PHOTO: KAREL BOCK/SHUTTERSTOCK.COM

    Although the brain grows little in volume after childhood, small structural changes, such as myelination and synapse pruning, continue into adulthood. Using multiecho functional magnetic resonance imaging to study subjects ranging in age from 8 to 46 years, Kundu et al. found that the functional organization of the brain shifts. Localized networks that characterize youth meld into larger and more functionally distinct networks with maturity. Not all parts of the brain change at the same rate; some regions are more dynamic. These regions correlate with aspects of cognition, such as the ability to monitor one's performance, to estimate others' intentions, or to develop a sense of self—all skills that are works in progress during adolescence.

    J. Neurosci. 38, 3559 (2018).

  2. Scholarly Publishing

    Lessons learned from the JACS Challenge

    1. Jake Yeston

    How do we gauge the importance of a scientific publication? Citation counts are, by their nature, crowdsourced, but their inherent meaning is somewhat unclear. To explore this question in more depth, Borchardt et al. asked chemists in a survey to look back at a 10-year-old issue of the Journal of the American Chemical Society (JACS) and predict, without checking, which three papers had been most highly cited. Respondents were also asked which papers they construed as most important and which they would share with other chemists or the public more broadly. Citations not only proved rather hard to predict, but also correlated poorly with the papers chosen to share.

    PLOS ONE 13, e0194903 (2018).

  3. Diabetes

    Staving off diabetes

    1. Priscilla N. Kelly

    Childhood obesity is a growing epidemic associated with increased risk of health issues later in life. Bjerregaard et al. asked whether, and at what age, shedding of excess pounds by overweight kids influenced their chance of developing type 2 diabetes as adults. The authors examined more than 62,000 Danish men for whom height and weight data were available from childhood into early adulthood. Individuals who were overweight throughout adolescence were four times as likely to develop adult type 2 diabetes. However, males who lost excess weight by age 13 cut their diabetes risk to that of those who were never overweight. Thus, maintaining a healthy body mass index throughout adolescence should reduce future chances of type 2 diabetes in men.

    N. Engl. J. Med. 10.1056/NEJMoa171323.1 (2018).

  4. Hematopoiesis

    Gut bugs encourage hematopoietic recovery

    1. Beverly A. Purnell

    Antibacterial measures are vital to the success of many clinical interventions. But increasing evidence shows that we need to be more discriminating in our efforts at bacterial extirpation. Profound immunodeficiency is a major challenge for postoperative bone marrow transplantation (BMT) patients. Considering that the gut microbiota is important for immune training during early life, Staffas et al. examined whether microbes in the intestine play a role in hematopoietic recovery after BMT. A major reduction in lymphocytes and neutrophils occurred in antibiotic-treated mice after surgery, accompanied by a loss of visceral fat. Hematopoietic stem and progenitor cells were less affected. Experiments with different antibiotics showed that ampicillin was associated with the poorest recovery and greatest fat loss because it caused near-total ablation of the microbiota.

    Cell Host Microbe 10.1016/j.chom.2018.03.002 (2018).

  5. Medicine

    A cool model for biomedical research

    1. Paula A. Kiberstis

    Hibernation is a fascinating physiological adaptation. One important question is which cellular signaling pathways allow hibernating mammals to enter and exit a cold-tolerant state without damage to cells and organs. Understanding this could conceivably lead to interventions that prolong the shelf life of donor organs before transplant. Ou et al. studied these pathways by establishing induced pluripotent stem cells (iPSCs) from a hibernating ground squirrel. Neurons derived from the iPSCs retained cold-resistant features, including microtubule stability. Comparison of ground squirrel and human iPSC-derived neurons revealed that differences in cold tolerance result in part from species differences in druggable signaling pathways that govern mitochondrial activity and protein quality-control mechanisms.

    Neural stem cells in thirteen-lined ground squirrels are geared for hibernation.

    PHOTO: POWER AND SYRED/SCIENCE SOURCE

    Cell 10.1016/j.cell.2018.03.010 (2018).

  6. Stellar Activity

    A brief flash from our closest neighbor

    1. Keith T. Smith

    Proxima Centauri, a small red dwarf, is the closest star to us other than the Sun. It hosts an exoplanet that may be about Earth's mass and might lie in the habitable zone, but many red dwarfs have frequent stellar flares that could strip away a planet's atmosphere. MacGregor et al. investigated millimeter-wavelength observations of Proxima Centauri, discovering that they contain a bright flare lasting less than a minute. Such short-duration millimeter-wavelength flaring has not previously been recognized and casts doubt on previous claims of dust lanes and asteroid belts in the system. Its effect on habitability is unknown.

    Astrophys. J. 855, L2 (2018).

  7. Microbiome

    A safe haven for the small

    1. Michael A. Funk

    The menu for gut microbes is decided by their host and is not always healthy. Linoleic acid, a component of soybean oil, is toxic to beneficial lactobacilli in the laboratory, but its role in shaping the microbiome is less clear. Di Rienzi et al. found that cultured lactobacilli developed strategies to resist the toxic fatty acid and that lactobacilli from mice fed a high-fat diet were more likely to be resistant than those fed a low-fat diet. However, in strains isolated from mice treated with linoleic acid, the resistant lactobacilli were not enriched. Gut bacteria may therefore be shielded from the harmful effects of linoleic acid by the local environment within the gut.

    eLife 10.7554/eLife.32581 (2018).