1,093 research outputs found
Effect of Combination Folic Acid, Vitamin B6 , and Vitamin B12 Supplementation on Fracture Risk in Women: A Randomized, Controlled Trial.
Epidemiologic studies have demonstrated an association of elevated plasma homocysteine levels with greater bone resorption and fracture risk. Vitamins B12 , B6 , and folic acid are cofactors in homocysteine metabolism, and supplementation with B vitamins is effective in lowering homocysteine levels in humans. However, randomized trials of supplemental B vitamins for reduction of fracture risk have been limited. Therefore, we performed an ancillary study to the Women's Antioxidant and Folic Acid Cardiovascular Study (WAFACS), a large randomized trial of women with preexisting cardiovascular disease or three or more coronary risk factors, to test whether a daily B vitamin intervention including folic acid (2.5 mg/day), vitamin B6 (50 mg/day), and vitamin B12 (1 mg/day) reduces nonspine fracture risk over 7.3 years of treatment and follow-up. Among 4810 women, we confirmed 349 nonspine fracture cases by centralized review of medical records. In a substudy of 300 women (150 in treatment group and 150 controls) with paired plasma samples at randomization and follow-up (7.3 years later), we measured two bone turnover markers, including C-terminal cross-linking telopeptide of type I collagen (CTX) and intact type I procollagen N-propeptide (P1NP). In Cox proportional hazards models based on intention-to-treat, we found no significant effects of B vitamin supplementation on nonspine fracture risk (relative hazard = 1.08; 95% confidence interval, 0.88 to 1.34). In a nested case-cohort analysis, there were no significant effects of B vitamins on fracture risk among women with elevated plasma homocysteine levels, or low levels of vitamins B12 or B6 , or folate at baseline. Furthermore, treatment with B vitamins had no effect on change in markers of bone turnover. We found no evidence that daily supplementation with B vitamins reduces fracture risk or rates of bone metabolism in middle-aged and older women at high risk of cardiovascular disease. © 2017 American Society for Bone and Mineral Research
Recreational Exposure to Low Concentrations of Microcystins During an Algal Bloom in a Small Lake
We measured microcystins in blood from people at risk for swallowing water or inhaling spray while swimming, water skiing, jet skiing, or boating during an algal bloom. We monitored water samples from a small lake as a Microcystis aeruginosa bloom developed. We recruited 97 people planning recreational activities in that lake and seven others who volunteered to recreate in a nearby bloom-free lake. We conducted our field study within a week of finding a 10-μg/L microcystin concentration. We analyzed water, air, and human blood samples for water quality, potential human pathogens, algal taxonomy, and microcystin concentrations. We interviewed study participants for demographic and current health symptom information. Water samples were assayed for potential respiratory viruses (adenoviruses and enteroviruses), but none were detected. We did find low concentrations of Escherichia coli, indicating fecal contamination. We found low levels of microcystins (2 μg/L to 5 μg/L) in the water and (<0.1 ng/m3) in the aerosol samples. Blood levels of microcystins for all participants were below the limit of detection (0.147μg/L). Given this low exposure level, study participants reported no symptom increases following recreational exposure to microcystins. This is the first study to report that water-based recreational activities can expose people to very low concentrations of aerosol-borne microcystins; we recently conducted another field study to assess exposures to higher concentrations of these algal toxins
Nanodiamond emulsions for enhanced quantum sensing and click-chemistry conjugation
Nanodiamonds containing nitrogen-vacancy (NV) centers can serve as colloidal
quantum sensors of local fields in biological and chemical environments.
However, nanodiamond surfaces are challenging to modify without degrading their
colloidal stability or the NV center's optical and spin properties. Here, we
report a simple and general method to coat nanodiamonds with a thin emulsion
layer that preserves their quantum features, enhances their colloidal
stability, and provides functional groups for subsequent crosslinking and
click-chemistry conjugation reactions. To demonstrate this technique, we
decorate the nanodiamonds with combinations of carboxyl- and azide-terminated
amphiphiles that enable conjugation using two different strategies. We study
the effect of the emulsion layer on the NV center's spin lifetime, and we
quantify the nanodiamonds' chemical sensitivity to paramagnetic ions using
relaxometry. This general approach to nanodiamond surface
functionalization will enable advances in quantum nanomedicine and biological
sensing.Comment: 52 pages, 42 figures (main text plus supplementary information
Cosmic Evolution Early Release Science (CEERS) survey: The colour evolution of galaxies in the distant Universe
The wavelength-coverage and sensitivity of JWST now enables us to probe the
rest-frame UV - optical spectral energy distributions (SEDs) of galaxies at
high-redshift (). From these SEDs it is, in principle, through SED fitting
possible to infer key physical properties, including stellar masses, star
formation rates, and dust attenuation. These in turn can be compared with the
predictions of galaxy formation simulations allowing us to validate and refine
the incorporated physics. However, the inference of physical properties,
particularly from photometry alone, can lead to large uncertainties and
potential biases. Instead, it is now possible, and common, for simulations to
be \emph{forward-modelled} to yield synthetic observations that can be compared
directly to real observations. In this work, we measure the JWST broadband
fluxes and colours of a robust sample of galaxies using the Cosmic
Evolution Early Release Science (CEERS) Survey. We then analyse predictions
from a variety of models using the same methodology and compare the
NIRCam/F277W magnitude distribution and NIRCam colours with observations. We
find that the predicted and observed magnitude distributions are similar, at
least at the distributions differ somewhat, though our
observed sample size is small and thus susceptible to statistical fluctuations.
Likewise, the predicted and observed colour evolution show broad agreement, at
least at . There is however some disagreement between the observed and
modelled strength of the strong line contribution. In particular all the models
fails to reproduce the F410M-F444W colour at , though, again, the sample
size is small here.Comment: 11 pages, 10 figures, submitted to MNRA
Models and Studies of Aging: Executive Summary of a Report from the U13 Conference Series
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148241/1/jgs15788.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148241/2/jgs15780-sup-0001-supinfo.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148241/3/jgs15788_am.pd
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BioTIME: A database of biodiversity time series for the Anthropocene.
MotivationThe BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.Main types of variables includedThe database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grainBioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2).Time period and grainBioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.Major taxa and level of measurementBioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.Software format.csv and .SQL
Calcium-sensing receptor antagonists abrogate airway hyperresponsiveness and inflammation in allergic asthma
Airway hyperresponsiveness and inflammation are fundamental hallmarks of allergic asthma that are accompanied by increases in certain polycations, such as eosinophil cationic protein. Levels of these cations in body fluids correlate with asthma severity. We show that polycations and elevated extracellular calcium activate the human recombinant and native calcium-sensing receptor (CaSR), leading to intracellular calcium mobilization, cyclic adenosine monophosphate breakdown, and p38 mitogen-activated protein kinase phosphorylation in airway smooth muscle (ASM) cells. These effects can be prevented by CaSR antagonists, termed calcilytics. Moreover, asthmatic patients and allergen-sensitized mice expressed more CaSR in ASMs than did their healthy counterparts. Indeed, polycations induced hyperreactivity in mouse bronchi, and this effect was prevented by calcilytics and absent in mice with CaSR ablation from ASM. Calcilytics also reduced airway hyperresponsiveness and inflammation in allergen-sensitized mice in vivo. These data show that a functional CaSR is up-regulated in asthmatic ASM and targeted by locally produced polycations to induce hyperresponsiveness and inflammation. Thus, calcilytics may represent effective asthma therapeutics
Efficient NIRCam Selection of Quiescent Galaxies at 3 < z < 6 in CEERS
© 2024 The Author(s). Published by the American Astronomical Society. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Substantial populations of massive quiescent galaxies at z ≥ 3 challenge our understanding of rapid galaxy growth and quenching over short timescales. In order to piece together this evolutionary puzzle, more statistical samples of these objects are required. Established techniques for identifying massive quiescent galaxies are increasingly inefficient and unconstrained at z > 3. As a result, studies report that as much as 70% of quiescent galaxies at z > 3 may be missed from existing surveys. In this work, we propose a new empirical color selection technique designed to select massive quiescent galaxies at 3 ≲ z ≲ 6 using JWST NIRCam imaging data. We use empirically constrained galaxy spectral energy distribution (SED) templates to define a region in the F277W − F444W versus F150W − F277W color plane that captures quiescent galaxies at z > 3. We apply these color selection criteria to the Cosmic Evolution Early Release Science (CEERS) Survey and use SED fitting on sources in the region to identify 44 candidate z ≳ 3 quiescent galaxies. Over half of these sources are newly discovered and, on average, exhibit specific star formation rates of poststarburst galaxies. Most of these sources would not be discovered using canonical UVJ diagrams. We derive volume density estimates of n ∼ 1–4 × 10−5 Mpc−3 at 3 < z < 5, finding excellent agreement with existing reports on similar populations in the CEERS field. Thanks to NIRCam’s wavelength coverage and sensitivity, this technique provides an efficient tool to search for large samples of these rare galaxies.Peer reviewe
Clinical outcomes after anterior cruciate ligament injury: panther symposium ACL injury clinical outcomes consensus group
© 2020, The Author(s). Purpose: A stringent outcome assessment is a key aspect for establishing evidence-based clinical guidelines for anterior cruciate ligament (ACL) injury treatment. The aim of this consensus statement was to establish what data should be reported when conducting an ACL outcome study, what specific outcome measurements should be used and at what follow-up time those outcomes should be assessed. Methods: To establish a standardized approach to assessment of clinical outcome after ACL treatment, a consensus meeting including a multidisciplinary group of ACL experts was held at the ACL Consensus Meeting Panther Symposium, Pittsburgh, PA; USA, in June 2019. The group reached consensus on nine statements by using a modified Delphi method. Results: In general, outcomes after ACL treatment can be divided into four robust categories—early adverse events, patient-reported outcomes, ACL graft failure/recurrent ligament disruption and clinical measures of knee function and structure. A comprehensive assessment following ACL treatment should aim to provide a complete overview of the treatment result, optimally including the various aspects of outcome categories. For most research questions, a minimum follow-up of 2 years with an optimal follow-up rate of 80% is necessary to achieve a comprehensive assessment. This should include clinical examination, any sustained re-injuries, validated knee-specific PROs and Health-Related Quality of Life questionnaires. In the mid- to long-term follow-up, the presence of osteoarthritis should be evaluated. Conclusion: This consensus paper provides practical guidelines for how the aforementioned entities of outcomes should be reported and suggests the preferred tools for a reliable and valid assessment of outcome after ACL treatment. Level of evidence: V
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