3,617 research outputs found
Language Barriers in Health Care Settings: An Annotated Bibliography of Research Literature
Provides an overview of resources related to the prevalence, role, and effects of language barriers and access in health care
Dysregulation of visual motion inhibition in major depression
Individuals with depression show depleted concentrations of the inhibitory neurotransmitter GABA in
occipital (visual) cortex, predicting weakened inhibition within their visual systems. Yet, visual inhibition
in depression remains largely unexplored. To fill this gap, we examined the inhibitory process of centersurround suppression (CSS) of visual motion in depressed individuals. Perceptual performance in discriminating the direction of motion was measured as a function of stimulus presentation time and
contrast in depressed individuals (n¼27) and controls (n¼22). CSS was operationalized as the accuracy
difference between conditions using large (7.5°) and small (1.5°) grating stimuli. Both depressed and
control participants displayed the expected advantage in accuracy for small stimuli at high contrast. A
significant interaction emerged between subject group, contrast level and presentation time, indicating
that alterations of CSS in depression were modulated by stimulus conditions. At high contrast, depressed
individuals showed significantly greater CSS than controls at the 66 ms presentation time (where the
effect peaked in both groups). The results' specificity and dependence on stimulus features such as
contrast, size and presentation time suggest that they arise from changes in early visual processing, and
are not the results of a generalized deficit or cognitive bias.Accepted versio
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Physiological, behavioral and subjective sadness reactivity in frontotemporal dementia subtypes.
Frontotemporal dementia (FTD), a neurodegenerative disease broadly characterized by socioemotional impairments, includes three clinical subtypes: behavioral variant FTD (bvFTD), semantic variant primary progressive aphasia (svPPA) and non-fluent variant primary progressive aphasia (nfvPPA). Emerging evidence has shown emotional reactivity impairments in bvFTD and svPPA, whereas emotional reactivity in nfvPPA is far less studied. In 105 patients with FTD (49 bvFTD, 31 svPPA and 25 nfvPPA) and 27 healthy controls, we examined three aspects of emotional reactivity (physiology, facial behavior and subjective experience) in response to a sad film. In a subset of the sample, we also examined the neural correlates of diminished aspects of reactivity using voxel-based morphometry. Results indicated that all three subtypes of FTD showed diminished physiological responding in respiration rate and diastolic blood pressure; patients with bvFTD and svPPA also showed diminished subjective experience, and no subtypes showed diminished facial behavior. Moreover, there were differences among the clinical subtypes in brain regions where smaller volumes were associated with diminished sadness reactivity. These results show that emotion impairments extend to sadness reactivity in FTD and underscore the importance of considering different aspects of sadness reactivity in multiple clinical subtypes for characterizing emotional deficits and associated neurodegeneration in FTD
Evaluating diverse electronic consultation programs with a common framework.
BackgroundElectronic consultation is an emerging mode of specialty care delivery that allows primary care providers and their patients to obtain specialist expertise without an in-person visit. While studies of individual programs have demonstrated benefits related to timely access to specialty care, electronic consultation programs have not achieved widespread use in the United States. The lack of common evaluation metrics across health systems and concerns related to the generalizability of existing evaluation efforts may be hampering further growth. We sought to identify gaps in knowledge related to the implementation of electronic consultation programs and develop a set of shared evaluation measures to promote further diffusion.MethodsUsing a case study approach, we apply the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) and the Quadruple Aim frameworks of evaluation to examine electronic consultation implementation across diverse delivery systems. Data are from 4 early adopter healthcare delivery systems (San Francisco Health Network, Mayo Clinic, Veterans Administration, Champlain Local Health Integration Network) that represent varied organizational structures, care for different patient populations, and have well-established multi-specialty electronic consultation programs. Data sources include published and unpublished quantitative data from each electronic consultation database and qualitative data from systems' end-users.ResultsOrganizational drivers of electronic consultation implementation were similar across the systems (challenges with timely and/or efficient access to specialty care), though unique system-level facilitators and barriers influenced reach, adoption and design. Effectiveness of implementation was consistent, with improved patient access to timely, perceived high-quality specialty expertise with few negative consequences, garnering high satisfaction among end-users. Data about patient-specific clinical outcomes are lacking, as are policies that provide guidance on the legal implications of electronic consultation and ideal remuneration strategies.ConclusionA core set of effectiveness and implementation metrics rooted in the Quadruple Aim may promote data-driven improvements and further diffusion of successful electronic consultation programs
An uncontaminated measurement of the escaping Lyman continuum at
Observations of reionization-era analogs at are a powerful tool for
constraining reionization. Rest-ultraviolet observations are particularly
useful, in which both direct and indirect tracers of ionizing-photon production
and escape can be observed. We analyse a sample of 124 galaxies from
the Keck Lyman Continuum Spectroscopic Survey, with sensitive spectroscopic
measurements of the Lyman continuum region. We present a method of removing
foreground contamination from our sample using high-resolution, multi-band
Hubble Space Telescope imaging. We re-measure the global properties of the
cleaned sample of 13 individually-detected Lyman continuum sources and 107
individually-undetected sources, including a sample-averaged absolute escape
fraction of and a sample-averaged ratio of
ionizing to non-ionizing ultraviolet flux density of , corrected for attenuation from the intergalactic and
circumgalactic media. Based on composite spectra, we also recover a strong
positive correlation between and Ly
equivalent width (W(Ly)) and a negative correlation between
and UV luminosity. As in previous work, we
interpret the relationship between and
W(Ly) in terms of the modulation of the escape of ionizing
radiation from star-forming galaxies based on the covering fraction of neutral
gas. We also use a W(Ly)-weighted to estimate an ionizing emissivity from star-forming galaxies at
as erg s Hz Mpc.
This estimate, evaluated using the uncontaminated sample of this work,
reaffirms that galaxies provide the majority of the ionizing background at
and beyond.Comment: 22 pages, 10 figures, submitted to MNRA
Chk1 Haploinsufficiency Results in Anemia and Defective Erythropoiesis
Erythropoiesis is a highly regulated and well-characterized developmental process responsible for providing the oxygen transport system of the body. However, few of the mechanisms involved in this process have been elucidated. Checkpoint Kinase 1 (Chk1) is best known for its role in the cell cycle and DNA damage pathways, and it has been shown to play a part in several pathways which when disrupted can lead to anemia.Here, we show that haploinsufficiency of Chk1 results in 30% of mice developing anemia within the first year of life. The anemic Chk1+/- mice exhibit distorted spleen and bone marrow architecture, and abnormal erythroid progenitors. Furthermore, Chk1+/- erythroid progenitors exhibit an increase in spontaneous DNA damage foci and improper contractile actin ring formation resulting in aberrant enucleation during erythropoiesis. A decrease in Chk1 RNA has also been observed in patients with refractory anemia with excess blasts, further supporting a role for Chk1 in clinical anemia.Clinical trials of Chk1 inhibitors are currently underway to treat cancer, and thus it will be important to track the effects of these drugs on red blood cell development over an extended period. Our results support a role for Chk1 in maintaining the balance between erythroid progenitors and enucleated erythroid cells during differentiation. We show disruptions in Chk1 levels can lead to anemia
Potential effects of phytoestrogen genistein in modulating acute methotrexate chemotherapy-induced osteoclastogenesis and bone damage in rats
Chemotherapy-induced bone damage is a frequent side effect which causes diminished bone mineral density and fracture in childhood cancer sufferers and survivors. The intensified use of anti-metabolite methotrexate (MTX) and other cytotoxic drugs has led to the need for a mechanistic understanding of chemotherapy-induced bone loss and for the development of protective treatments. Using a young rat MTX-induced bone loss model, we investigated potential bone protective effects of phytoestrogen genistein. Oral gavages of genistein (20 mg/kg) were administered daily, for seven days before, five days during, and three days after five once-daily injections (sc) of MTX (0.75 mg/kg). MTX treatment reduced body weight gain and tibial metaphyseal trabecular bone volume (p < 0.001), increased osteoclast density on the trabecular bone surface (p < 0.05), and increased the bone marrow adipocyte number in lower metaphyseal bone (p < 0.001). Genistein supplementation preserved body weight gain (p < 0.05) and inhibited ex vivo osteoclast formation of bone marrow cells from MTX-treated rats (p < 0.001). However, MTX-induced changes in bone volume, trabecular architecture, metaphyseal mRNA expression of pro-osteoclastogenic cytokines, and marrow adiposity were not significantly affected by the co-administration of genistein. This study suggests that genistein may suppress MTX-induced osteoclastogenesis; however, further studies are required to examine its potential in protecting against MTX chemotherapy-induced bone damage
Particle Production at Large Transverse Momentum with ALICE
We present transverse momentum distributions of inclusive charged particles
and identified hadrons in and Pb--Pb collisions at \rs= 2.76 TeV,
measured by ALICE at the LHC. The Pb--Pb data are presented in intervals of
collision centrality and cover transverse momenta up to 50 GeV/. Nuclear
medium effects are studied in terms of the nuclear modification factor \raa.
The results indicate a strong suppression of high- particles in Pb--Pb
collisions, consistent with a large energy loss of hard-scattered partons in
the hot, dense and long-lived medium created at the LHC. We compare the
preliminary results for inclusive charged particles to previous results from
RHIC and calculations from energy loss models. Furthermore, we compare the
nuclear modification factors of inclusive charged particles to those of
identified , , K, and .Comment: Talk given at Quark Matter 2011 conferenc
The connection between the escape of ionizing radiation and galaxy properties at z~3 in the Keck Lyman Continuum Spectroscopic Survey
The connection between the escape fraction of ionizing radiation ()
and the properties of galaxies, such as stellar mass (M*), age, star-formation
rate (SFR), and dust content, are key inputs for reionization models, but many
of these relationships remain untested at high redshift. We present an analysis
of a sample of 96 z~3 galaxies from the Keck Lyman Continuum Spectroscopic
Survey (KLCS). These galaxies have both sensitive Keck/LRIS spectroscopic
measurements of the Lyman continuum (LyC) region, and multi-band photometry
that places constraints on stellar population parameters. We construct
composite spectra from subsamples binned as a function of galaxy property and
quantify the ionizing-photon escape for each composite. We find a significant
anti-correlation between and M*, consistent with predictions from
cosmological zoom-in simulations. We also find significant anti-correlation
between and E(B-V), encoding the underlying physics of LyC escape in
our sample. We also find no significant correlation between and
either stellar age or specific SFR (=SFR/M*), challenging interpretations that
synchronize recent star formation and favorable conditions for ionizing escape.
The galaxy properties now shown to correlate with in the KLCS are
Ly equivalent width, UV Luminosity, M*, SFR, and E(B-V), but not age or
sSFR. To date, this is the most comprehensive analysis of galaxy properties and
LyC escape at high redshift, and will be used to guide future models and
observations of the reionization epoch.Comment: 13 pages, 5 figures, submitted to MNRA
Effects of resveratrol supplementation on methotrexate chemotherapy‐induced bone loss
Intensive cancer chemotherapy is known to cause bone defects, which currently lack treatments. This study investigated the effects of polyphenol resveratrol (RES) in preventing bone defects in rats caused by methotrexate (MTX), a commonly used antimetabolite in childhood oncology. Young rats received five daily MTX injections at 0.75 mg/kg/day. RES was orally gavaged daily for seven days prior to, and during, five‐day MTX administration. MTX reduced growth plate thickness, primary spongiosa height, trabecular bone volume, increased marrow adipocyte density, and increased mRNA expression of the osteogenic, adipogenic, and osteoclastogenic factors in the tibial bone. RES at 10 mg/kg was found not to affect bone health in normal rats, but to aggravate the bone damage in MTX‐treated rats. However, RES supplementation at 1 mg/kg preserved the growth plate, primary spongiosa, bone volume, and lowered the adipocyte density. It maintained expression of genes involved in osteogenesis and decreased expression of adipogenic and osteoclastogenic factors. RES suppressed osteoclast formation ex vivo of bone marrow cells from the treated rats. These data suggest that MTX can enhance osteoclast and adipocyte formation and cause bone loss, and that RES supplementation at 1 mg/kg may potentially prevent these bone defects
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