Revisiting the refeeding syndrome: Results of a systematic review.

OBJECTIVE Although described >70 y ago, the refeeding syndrome (RFS) remains understudied with lack of standardized definition and treatment recommendations. The aim of this systematic review was to gather evidence regarding standardized definition, incidence rate and time course of occurrence, association with adverse clinical outcomes, risk factors, and therapeutic strategies to prevent or treat this condition. METHODS We searched MEDLINE and EMBASE for interventional and observational clinical trials focusing on RFS, excluding case reports and reviews. We extracted data based on a predefined case report form and assessed bias. RESULTS Of 2207 potential abstracts, 45 records with a total of 6608 patients were included (3 interventional trials, 16 studies focusing on anorexic patients). Definitions for RFS were highly heterogenous with most studies relying on blood electrolyte disturbances only and others also including clinical symptoms. Incidence rates varied between 0% and 80%, depending on the definition and patient population studied. Occurrence was mostly within the first 72 h of start of nutritional therapy. Most of the risk factors were in accordance with National Institute for Health and Care Excellence guidelines, with older age and enteral feeding being additional factors. There was no strong evidence regarding association of RFS and adverse outcomes, as well as regarding preventive measures and treatment algorithms. CONCLUSION This systematic review focusing on RFS found consensus regarding risk factors and timing of occurrence, but wide variations regarding definition, reported incidence rates, preventive measures and treatment recommendations. Further research to fill this gap is urgently needed

Management and prevention of refeeding syndrome in medical inpatients: An evidence-based and consensus-supported algorithm

Objectives:Refeeding syndrome (RFS) can be a life-threatening metabolic condition after nutritional re-plenishment if not recognized early and treated adequately. There is a lack of evidence-based treatmentand monitoring algorithm for daily clinical practice. The aim of the study was to propose an expert con-sensus guideline for RFS for the medical inpatient (not including anorexic patients) regarding risk factors,diagnostic criteria, and preventive and therapeutic measures based on a previous systematic literaturesearch.Methods:Based on a recent qualitative systematic review on the topic, we developed clinically relevantrecommendations as well as a treatment and monitoring algorithm for the clinical management of in-patients regarding RFS. With international experts, these recommendations were discussed and agreementwith the recommendation was rated.Results:Upon hospital admission, we recommend the use of specific screening criteria (i.e., low bodymass index, large unintentional weight loss, little or no nutritional intake, history of alcohol or drug abuse)for risk assessment regarding the occurrence of RFS. According to the patient’s individual risk for RFS, acareful start of nutritional therapy with a stepwise increase in energy and fluids goals and supplemen-tation of electrolyte and vitamins, as well as close clinical monitoring, is recommended. We also proposecriteria for the diagnosis of imminent and manifest RFS with practical treatment recommendations withadoption of the nutritional therapy.Conclusion:Based on the available evidence, we developed a practical algorithm for risk assessment, treat-ment, and monitoring of RFS in medical inpatients. In daily routine clinical care, this may help to optimizeand standardize the management of this vulnerable patient population. We encourage future quality studiesto further refine these recommendations

Reduced MEK inhibition preserves genomic stability in naive human embryonic stem cells

Human embryonic stem cells (hESCs) can be captured in a primed state in which they resemble the postimplantation epiblast, or in a naive state where they resemble the preimplantation epiblast. Naive-cell-specific culture conditions allow the study of preimplantation development ex vivo but reportedly lead to chromosomal abnormalities, which compromises their utility in research and potential therapeutic applications. Although MEK inhibition is essential for the naive state, here we show that reduced MEK inhibition facilitated the establishment and maintenance of naive hESCs that retained naive-cell-specific features, including global DNA hypomethylation, HERVK expression, and two active X chromosomes. We further show that hESCs cultured under these modified conditions proliferated more rapidly; accrued fewer chromosomal abnormalities; and displayed changes in the phosphorylation levels of MAPK components, regulators of DNA damage/repair, and cell cycle. We thus provide a simple modification to current methods that can enable robust growth and reduced genomic instability in naive hESCs

Size and Shape Constraints of (486958) Arrokoth from Stellar Occultations

International audienceWe present the results from four stellar occultations by (486958) Arrokoth, the flyby target of the New Horizons extended mission. Three of the four efforts led to positive detections of the body, and all constrained the presence of rings and other debris, finding none. Twenty-five mobile stations were deployed for 2017 June 3 and augmented by fixed telescopes. There were no positive detections from this effort. The event on 2017 July 10 was observed by the Stratospheric Observatory for Infrared Astronomy with one very short chord. Twenty-four deployed stations on 2017 July 17 resulted in five chords that clearly showed a complicated shape consistent with a contact binary with rough dimensions of 20 by 30 km for the overall outline. A visible albedo of 10% was derived from these data. Twenty-two systems were deployed for the fourth event on 2018 August 4 and resulted in two chords. The combination of the occultation data and the flyby results provides a significant refinement of the rotation period, now estimated to be 15.9380 ± 0.0005 hr. The occultation data also provided high-precision astrometric constraints on the position of the object that were crucial for supporting the navigation for the New Horizons flyby. This work demonstrates an effective method for obtaining detailed size and shape information and probing for rings and dust on distant Kuiper Belt objects as well as being an important source of positional data that can aid in spacecraft navigation that is particularly useful for small and distant bodies

The KELT Follow-up Network and Transit False-positive Catalog: Pre-vetted False Positives for TESS

The Kilodegree Extremely Little Telescope (KELT) project has been conducting a photometric survey for transiting planets orbiting bright stars for over ten years. The KELT images have a pixel scale of ~23"/pixel---very similar to that of NASA's Transiting Exoplanet Survey Satellite (TESS)---as well as a large point spread function, and the KELT reduction pipeline uses a weighted photometric aperture with radius 3'. At this angular scale, multiple stars are typically blended in the photometric apertures. In order to identify false positives and confirm transiting exoplanets, we have assembled a follow-up network (KELT-FUN) to conduct imaging with higher spatial resolution, cadence, and photometric precision than the KELT telescopes, as well as spectroscopic observations of the candidate host stars. The KELT-FUN team has followed-up over 1,600 planet candidates since 2011, resulting in more than 20 planet discoveries. Excluding ~450 false alarms of non-astrophysical origin (i.e., instrumental noise or systematics), we present an all-sky catalog of the 1,128 bright stars (6<V<10) that show transit-like features in the KELT light curves, but which were subsequently determined to be astrophysical false positives (FPs) after photometric and/or spectroscopic follow-up observations. The KELT-FUN team continues to pursue KELT and other planet candidates and will eventually follow up certain classes of TESS candidates. The KELT FP catalog will help minimize the duplication of follow-up observations by current and future transit surveys such as TESS.Comment: Accepted for publication in AJ, 21 pages, 12 figures, 7 table