1,649 research outputs found

    Vitamin D Status of Infants in Northeastern Rural Bangladesh: Preliminary Observations and a Review of Potential Determinants

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    Vitamin D deficiency is a global public-health concern, even in tropical regions where the risk of deficiency was previously assumed to be low due to cutaneous vitamin D synthesis stimulated by exposure to sun. Poor vitamin D status, indicated by low serum concentrations of 25-hydroxyvitamin D [25(OH)D], has been observed in South Asian populations. However, limited information is available on the vitamin D status of young infants in this region. Therefore, to gain preliminary insights into the vitamin D status of infants in rural Bangladesh, 25(OH)D was assessed in a group of community-sampled control participants in a pneumonia case-control study in rural Sylhet, Bangladesh (25°N) during the winter dry season (January-February). Among 29 infants aged 1-6 months, the mean 25(OH)D was 36.7 nmol/L [95% confidence interval (CI) 30.2-43.2]. The proportion of infants with vitamin D deficiency defined by 25(OH)D <25 nmol/L was 28% (95% CI 10-45), 59% (95% CI 40-78) had 25(OH)D<40 nmol/L, and all were below 80 nmol/L. From one to six months, there was a positive correlation between age and 25(OH)D (Spearman=0.65; p=0.0001). Within a larger group of 74 infants and toddlers aged 1-17 months (cases and controls recruited for the pneumonia study), young age was the only significant risk factor for vitamin D deficiency [25(OH)D <25 nmol/L]. Since conservative maternal clothing practices (i.e. veiling) and low frequency of intake of foods from animal source (other than fish) were common among the mothers of the participants, determinants of low maternal-infant 25(OH)D in Bangladesh deserve more detailed consideration in future studies. In conclusion, the vitamin D status in young infants in rural Sylhet, Bangladesh, was poorer than might be expected based on geographic considerations. The causes and consequences of low 25(OH)D in infancy and early childhood in this setting remain to be established

    Definition of Terms, Style, and Conventions Used in A.S.P.E.N. Guidelines and Standards

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141145/1/ncp0281.pd

    The relationship between ciliary neurotrophic factor (CNTF) genotype and motor unit physiology: preliminary studies

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    BACKGROUND: Ciliary neurotrophic factor (CNTF) is important for neuronal and muscle development, and genetic variation in the CNTF gene has been associated with muscle strength. The effect of CNTF on nerve development suggests that CNTF genotype may be associated with force production via its influence on motor unit size and firing patterns. The purpose of this study is to examine whether CNTF genotype differentially affects motor unit activation in the vastus medialis with increasing isometric force during knee extension. RESULTS: Sixty-nine healthy subjects were genotyped for the presence of the G and A (null) alleles in the CNTF gene (n = 57 G/G, 12 G/A). They were tested using a dynamometer during submaximal isometric knee extension contractions that were from 10–50% of their maximal strength. During the contractions, the vastus medialis was studied using surface and intramuscular electromyography with spiked triggered averaging to assess surface-detected motor unit potential (SMUP) area and mean firing rates (mFR) from identified motor units. CNTF genotyping was performed using standard PCR techniques from DNA obtained from leucocytes of whole blood samples. The CNTF G/A genotype was associated with smaller SMUP area motor units and lower mFR at higher force levels, and fewer but larger units at lower force levels than G/G homozygotes. The two groups used motor units with different size and activation characteristics with increasing force generation. While G/G subjects tended to utilize larger motor units with increasing force, G/A subjects showed relatively less increase in size by using relatively larger units at lower force levels. At higher force levels, G/A subjects were able to generate more force per motor unit size suggesting more efficient motor unit function with increasing muscle force. CONCLUSION: Differential motor unit responses were observed between CNTF genotypes at force levels utilized in daily activities

    The Lyman alpha reference sample. VII. Spatially resolved Hα\alpha kinematics

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    We present integral field spectroscopic observations with the Potsdam Multi Aperture Spectrophotometer of all 14 galaxies in the z∌0.1z\sim 0.1 Lyman Alpha Reference Sample (LARS). We produce 2D line of sight velocity maps and velocity dispersion maps from the Balmer α\alpha (Hα\alpha) emission in our data cubes. These maps trace the spectral and spatial properties of the LARS galaxies' intrinsic Lyα\alpha radiation field. We show our kinematic maps spatially registered onto the Hubble Space Telescope Hα\alpha and Lyman α\alpha (Lyα\alpha) images. Only for individual galaxies a causal connection between spatially resolved Hα\alpha kinematics and Lyα\alpha photometry can be conjectured. However, no general trend can be established for the whole sample. Furthermore, we compute non-parametric global kinematical statistics -- intrinsic velocity dispersion σ0\sigma_0, shearing velocity vshearv_\mathrm{shear}, and the vshear/σ0v_\mathrm{shear}/\sigma_0 ratio -- from our kinematic maps. In general LARS galaxies are characterised by high intrinsic velocity dispersions (54\,km\,s−1^{-1} median) and low shearing velocities (65\,km\,s−1^{-1} median). vshear/σ0v_\mathrm{shear}/\sigma_0 values range from 0.5 to 3.2 with an average of 1.5. Noteworthy, five galaxies of the sample are dispersion dominated systems with vshear/σ0<1v_\mathrm{shear}/\sigma_0 <1 and are thus kinematically similar to turbulent star forming galaxies seen at high redshift. When linking our kinematical statistics to the global LARS Lyα\alpha properties, we find that dispersion dominated systems show higher Lyα\alpha equivalent widths and higher Lyα\alpha escape fractions than systems with vshear/σ0>1v_\mathrm{shear}/\sigma_0 > 1. Our result indicates that turbulence in actively star-forming systems is causally connected to interstellar medium conditions that favour an escape of Lyα\alpha radiation.Comment: 26 pages, 15 figures, accepted for publication in A&

    Aberrant Hierarchical Prediction Errors Are Associated With Transition to Psychosis: A Computational Single-Trial Analysis of the Mismatch Negativity

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    Background: Mismatch negativity reductions are among the most reliable biomarkers for schizophrenia and have been associated with increased risk for conversion to psychosis in individuals who are at clinical high risk for psychosis (CHR-P). Here, we adopted a computational approach to develop a mechanistic model of mismatch negativity reductions in CHR-P individuals and patients early in the course of schizophrenia. // Methods: Electroencephalography was recorded in 38 CHR-P individuals (15 converters), 19 patients early in the course of schizophrenia (≀5 years), and 44 healthy control participants during three different auditory oddball mismatch negativity paradigms including 10% duration, frequency, or double deviants, respectively. We modeled sensory learning with the hierarchical Gaussian filter and extracted precision-weighted prediction error trajectories from the model to assess how the expression of hierarchical prediction errors modulated electroencephalography amplitudes over sensor space and time. // Results: Both low-level sensory and high-level volatility precision-weighted prediction errors were altered in CHR-P individuals and patients early in the course of schizophrenia compared with healthy control participants. Moreover, low-level precision-weighted prediction errors were significantly different in CHR-P individuals who later converted to psychosis compared with nonconverters. // Conclusions: Our results implicate altered processing of hierarchical prediction errors as a computational mechanism in early psychosis consistent with predictive coding accounts of psychosis. This computational model seems to capture pathophysiological mechanisms that are relevant to early psychosis and the risk for future psychosis in CHR-P individuals and may serve as predictive biomarkers and mechanistic targets for the development of novel treatments

    Contacting domains segregate a lipid transporter from a solute transporter in the malarial host–parasite interface

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    While membrane contact sites between intracellular organelles are abundant, little is known about the contacts between membranes that delimit extracellular junctions within cells, such as intracellular parasites. Here authors demonstrate the segregation of a lipid transporter from a solute transporter in the malarial host-parasite interface

    Minimal Clinically Important Differences for the Modified Rodnan Skin Score: Results from the Scleroderma Lung Studies (SLS-I and SLS-II)

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    Abstract Objective This study aimed to assess the minimal clinically important differences (MCIDs) for the modified Rodnan skin score (mRSS) using combined data from the Scleroderma Lung Studies (I and II). Methods MCID estimates for the mRSS at 12 months were calculated using three anchors: change in scores on the Health Assessment Questionnaire- Disability Index from baseline to 12 months, change in scores on the Patient Global Assessment from baseline to 12 months, and answer at 12 month for the Short Form-36 health transition question “Compared to one year ago, how would you rate your health in general now?” We determined the mRSS MCID estimates for all participants and for those with diffuse cutaneous systemic sclerosis (dcSSc). We then assessed associations between MCID estimates of mRSS improvement and patient-reported outcomes, using Student’s t test to compare the mean differences in patient outcomes between those who met the MCID improvement criteria versus those who did not meet the improvement criteria. Results The mean (SD) mRSS at baseline was 14.75 (10.72) for all participants and 20.93 (9.61) for those with dcSSc. The MCID estimate for mRSS improvement at 12 months ranged from 3 to 4 units for the overall group (improvement of 20–27% from baseline) and was 5 units for those with dcSSc (improvement of 24% from baseline). Those who met the mRSS MCID improvement criteria had statistically significant improvements in scores on the Short Form-36 Physical Component Summary, the Transition Dyspnea Index, and joint contractures at 12 months. Conclusion MCID estimates for the mRSS were 3–4 units for all participants and 5 units for those with dcSSc. These findings are consistent with previously reported MCID estimates for systemic sclerosis.https://deepblue.lib.umich.edu/bitstream/2027.42/147346/1/13075_2019_Article_1809.pd
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