624 research outputs found

    Randomized trial of polychromatic blue-enriched light for circadian phase shifting, melatonin suppression, and alerting responses.

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    Wavelength comparisons have indicated that circadian phase-shifting and enhancement of subjective and EEG-correlates of alertness have a higher sensitivity to short wavelength visible light. The aim of the current study was to test whether polychromatic light enriched in the blue portion of the spectrum (17,000 K) has increased efficacy for melatonin suppression, circadian phase-shifting, and alertness as compared to an equal photon density exposure to a standard white polychromatic light (4000 K). Twenty healthy participants were studied in a time-free environment for 7 days. The protocol included two baseline days followed by a 26-h constant routine (CR1) to assess initial circadian phase. Following CR1, participants were exposed to a full-field fluorescent light (1 × 10 14 photons/cm 2 /s, 4000 K or 17,000 K, n = 10/condition) for 6.5 h during the biological night. Following an 8 h recovery sleep, a second 30-h CR was performed. Melatonin suppression was assessed from the difference during the light exposure and the corresponding clock time 24 h earlier during CR1. Phase-shifts were calculated from the clock time difference in dim light melatonin onset time (DLMO) between CR1 and CR2. Blue-enriched light caused significantly greater suppression of melatonin than standard light ((mean ± SD) 70.9 ± 19.6% and 42.8 ± 29.1%, respectively, p \u3c 0.05). There was no significant difference in the magnitude of phase delay shifts. Blue-enriched light significantly improved subjective alertness (p \u3c 0.05) but no differences were found for objective alertness. These data contribute to the optimization of the short wavelength-enriched spectra and intensities needed for circadian, neuroendocrine and neurobehavioral regulation

    Computational Modeling to Limit the Impact Displays and Indicator Lights Have on Habitable Volume Operational Lighting Constraints

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    Even with no ambient lighting system "on", the International Space Station glows at night. The glow is caused by indicator lamps and displays that are not included with the specification of the ambient lighting system. How does this impact efforts to improve the astronaut's lighting environment to promote more effective sleep patterns? Do the extra indicators and displays add enough light to change the spectrum of light the crew sees during the day as well? If spacecraft environments are specifically engineered to have an ambient lighting system that emits a spectrum promoting a healthy circadian response, is there a way control the impact? The goal of this project is to investigate how additional light sources, such as displays and indicators change the effective light spectrum of the architectural lighting system and how impacts can be mitigated

    Computational Modeling to Limit the Impact Displays and Indicator Lights Have on Habitable Volume Operational Lighting Constraints

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    NASA has demonstrated an interest in improving astronaut health and performance through the installment of a new lighting countermeasure on the International Space Station. The Solid State Lighting Assembly (SSLA) system is designed to positively influence astronaut health by providing a daily change to light spectrum to improve circadian entrainment. Unfortunately, existing NASA standards and requirements define ambient light level requirements for crew sleep and other tasks, yet the number of light-emitting diode (LED) indicators and displays within a habitable volume is currently uncontrolled. Because each of these light sources has its own unique spectral properties, the additive lighting environment ends up becoming something different from what was planned or researched. Restricting the use of displays and indicators is not a solution because these systems provide beneficial crew feedback

    EczemaNet: automating detection and severity assessment of atopic dermatitis

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    Atopic dermatitis (AD), also known as eczema, is one of themost common chronic skin diseases. AD severity is primarily evaluatedbased on visual inspections by clinicians, but is subjective and has largeinter- and intra-observer variability in many clinical study settings. Toaid the standardisation and automating the evaluation of AD severity,this paper introduces a CNN computer vision pipeline, EczemaNet, thatfirst detects areas of AD from photographs and then makes probabilisticpredictions on the severity of the disease. EczemaNet combines trans-fer and multitask learning, ordinal classification, and ensembling overcrops to make its final predictions. We test EczemaNet using a set of im-ages acquired in a published clinical trial, and demonstrate low RMSEwith well-calibrated prediction intervals. We show the effectiveness of us-ing CNNs for non-neoplastic dermatological diseases with a medium-sizedataset, and their potential for more efficiently and objectively evaluatingAD severity, which has greater clinical relevance than mere classification

    An improved competitive inhibition enzymatic immunoassay method for tetrodotoxin quantification

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    Quantifying tetrodotoxin (TTX) has been a challenge in both ecological and medical research due to the cost, time and training required of most quantification techniques. Here we present a modified Competitive Inhibition Enzymatic Immunoassay for the quantification of TTX, and to aid researchers in the optimization of this technique for widespread use with a high degree of accuracy and repeatability

    Regulation of L1 expression and retrotransposition by melatonin and its receptor: implications for cancer risk associated with light exposure at night.

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    Expression of long interspersed element-1 (L1) is upregulated in many human malignancies. L1 can introduce genomic instability via insertional mutagenesis and DNA double-strand breaks, both of which may promote cancer. Light exposure at night, a recently recognized carcinogen, is associated with an increased risk of cancer in shift workers. We report that melatonin receptor 1 inhibits mobilization of L1 in cultured cells through downregulation of L1 mRNA and ORF1 protein. The addition of melatonin receptor antagonists abolishes the MT1 effect on retrotransposition in a dose-dependent manner. Furthermore, melatonin-rich, but not melatonin-poor, human blood collected at different times during the circadian cycle suppresses endogenous L1 mRNA during in situ perfusion of tissue-isolated xenografts of human cancer. Supplementation of human blood with exogenous melatonin or melatonin receptor antagonist during the in situ perfusion establishes a receptor-mediated action of melatonin on L1 expression. Combined tissue culture and in vivo data support that environmental light exposure of the host regulates expression of L1 elements in tumors. Our data imply that light-induced suppression of melatonin production in shift workers may increase L1-induced genomic instability in their genomes and suggest a possible connection between L1 activity and increased incidence of cancer associated with circadian disruption

    Report from the third international consensus meeting to harmonise core outcome measures for atopic eczema/dermatitis clinical trials (HOME).

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    This report provides a summary of the third meeting of the Harmonising Outcome Measures for Eczema (HOME) initiative held in San Diego, CA, U.S.A., 6-7 April 2013 (HOME III). The meeting addressed the four domains that had previously been agreed should be measured in every eczema clinical trial: clinical signs, patient-reported symptoms, long-term control and quality of life. Formal presentations and nominal group techniques were used at this working meeting, attended by 56 voting participants (31 of whom were dermatologists). Significant progress was made on the domain of clinical signs. Without reference to any named scales, it was agreed that the intensity and extent of erythema, excoriation, oedema/papulation and lichenification should be included in the core outcome measure for the scale to have content validity. The group then discussed a systematic review of all scales measuring the clinical signs of eczema and their measurement properties, followed by a consensus vote on which scale to recommend for inclusion in the core outcome set. Research into the remaining three domains was presented, followed by discussions. The symptoms group and quality of life groups need to systematically identify all available tools and rate the quality of the tools. A definition of long-term control is needed before progress can be made towards recommending a core outcome measure

    Mapping randomized controlled trials of treatments for eczema - The GREAT database (The Global Resource of Eczema Trials: a collection of key data on randomized controlled trials of treatments for eczema from 2000 to 2010)

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    <p>Abstract</p> <p>Background</p> <p>Massive duplication of effort occurs when researchers all over the world undertake extensive searches for randomized controlled trials when preparing systematic reviews, when developing evidence-based guidelines and when applying for research funding for eczema treatments. Such duplication wastes valuable resources.</p> <p>Searching for randomized controlled trials of eczema is a laborious task involving scrutiny of thousands of individual references from diverse electronic databases in order to obtain a few papers of interest. Clinicians and patients who wish to find out more about a particular treatment are at risk of missing the relevant evidence if they are not trained in electronic bibliographic searching. Systematic reviews cannot be relied upon to comprehensively inform current optimal eczema treatments due to incomplete coverage and because many may be out of date.</p> <p>An international, publically available and comprehensive resource which brings together all randomized controlled trials on eczema treatment using a highly sensitive search has the potential to release more filtered knowledge about patient care to those who need it most and to significantly shorten the duration and costs of many clinical eczema research and guideline projects.</p> <p>Description</p> <p>The Global Resource of EczemA Trials brings together information on all randomized controlled trials of eczema treatments published from the beginning of 2000 up to the end of 2010 and will be updated every month.</p> <p>We searched the Cochrane Central Register of Controlled Trials in <it>The Cochrane Library </it>and the Cochrane Skin Group Specialised Register, MEDLINE, EMBASE, LILACS, AMED and CINHAL databases. We included 268 RCTs (24<sup>th </sup>March 2011) covering over 70 different treatment interventions.</p> <p>The structure of the Global Resource of Eczema Trials allows the user as much, or as little, specificity when retrieving information on trials as they wish, in an easy to use format. For each trial, the database gives the citation for the published report and also provides enough information to enable a user to decide whether the trial is worth further scrutiny.</p> <p>Conclusions</p> <p>The Global Resource of Eczema Trials has been created to facilitate knowledge mobilization into healthcare and to reduce wastage of research time through unnecessary duplication. The collective time saved by research groups around the world can now be used to make strides in optimising the treatment of eczema, in order to further benefit people with eczema. The database can be accessed free of charge at <url>http://www.greatdatabase.org.uk</url></p
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