626 research outputs found

    Recent trauma and acute infection as risk factors for childhood arterial ischemic stroke.

    Get PDF
    ObjectiveTrauma and acute infection have been associated with stroke in adults, and are prevalent exposures in children. We hypothesized that these environmental factors are independently associated with childhood arterial ischemic stroke (AIS).MethodsIn a case-control study nested within a cohort of 2.5 million children (≤19 years old) enrolled in an integrated health care plan (1993-2007), childhood AIS cases (n = 126) were identified from electronic records and confirmed through chart review. Age- and facility-matched controls (n = 378) were randomly selected from the cohort. Exposures were determined from review of medical records prior to the stroke diagnosis, or the same date for the paired controls; time windows were defined a priori.ResultsA medical encounter for head or neck trauma within the prior 12 weeks was an independent risk factor for childhood AIS (odds ratio [OR], 7.5; 95% confidence interval [CI], 2.9-19.3), present in 12% of cases (1.6% of controls). Median time from trauma to stroke was 0.5 days (interquartile range, 0-2 days); post hoc redefinition of trauma exposure (prior 1 week) was more strongly associated with AIS: OR, 39; 95% CI, 5.1-298. A medical encounter for a minor acute infection (prior 4 weeks) was also an independent risk factor (OR, 4.6; 95% CI, 2.6-8.2), present in 33% of cases (13% of controls). No single infection type predominated. Only 2 cases had exposure to trauma and infection.InterpretationTrauma and acute infection are common independent risk factors for childhood AIS, and may be targets for stroke prevention strategies

    Optical/IR from ground

    Get PDF
    Optical/infrared (O/IR) astronomy in the 1990's is reviewed. The following subject areas are included: research environment; science opportunities; technical development of the 1980's and opportunities for the 1990's; and ground-based O/IR astronomy outside the U.S. Recommendations are presented for: (1) large scale programs (Priority 1: a coordinated program for large O/IR telescopes); (2) medium scale programs (Priority 1: a coordinated program for high angular resolution; Priority 2: a new generation of 4-m class telescopes); (3) small scale programs (Priority 1: near-IR and optical all-sky surveys; Priority 2: a National Astrometric Facility); and (4) infrastructure issues (develop, purchase, and distribute optical CCDs and infrared arrays; a program to support large optics technology; a new generation of large filled aperture telescopes; a program to archive and disseminate astronomical databases; and a program for training new instrumentalists

    Metabolic Syndrome and Early-Onset Coronary Artery Disease Is the Whole Greater Than Its Parts?

    Get PDF
    ObjectivesWe sought to examine the association between the metabolic syndrome (MetS) (defined both by the 2001 National Cholesterol Educational Program Adult Treatment Panel III [ATP-III] definition and the American Heart Association/National Heart, Lung and Blood Institute [AHA/NHLBI] revision incorporating the lower threshold for impaired fasting glucose [IFG]) and early-onset coronary artery disease (CAD).BackgroundThe impact of MetS on premature CAD has not been studied extensively. Lowering the threshold to define the IFG component (from 110 to 100 mg/dl) and the value of the syndrome as a whole versus its individual components are subjects of intense debate.MethodsWe performed a case-control study with 393 early-onset CAD subjects (acute myocardial infarction, angina with ≥50% stenosis, or coronary revascularization) in men under age 46 years or women under age 56 years and 393 control subjects individually matched for gender, age, and race/ethnicity.ResultsBy conditional logistic regression, presence of ATP-III MetS without diabetes (adjusted odds ratio [adj-OR] 4.9; 95% confidence interval [CI] 3.4 to 8.0) and with diabetes (adj-OR 8.0, 95% CI 4.39 to 14.6) was a strong independent determinant of early-onset CAD. Using the AHA/NHLBI revision, these ORs became slightly stronger. However, neither definition of MetS remained significantly associated with early-onset CAD in multivariate models adjusting for individual components.ConclusionsThe presence of MetS imparts a high risk of early-onset clinical CAD, but the prognostic information associated with the syndrome is not greater than the sum of its parts

    Effective Temperatures of a Driven System Near Jamming

    Get PDF
    Fluctuations in a model of a sheared, zero-temperature foam are studied numerically. Five different quantities that reduce to the true temperature in an equilibrium thermal system are calculated. All five have the same shear-rate dependence, and three have the same value. Near the onset of jamming, the relaxation time is the same function of these three temperatures in the sheared system as of the true temperature in an unsheared system. These results imply that statistical mechanics is useful for the system and provide strong support for the concept of jamming.Comment: 4 pages, 4 postscript figure

    Hyperfiltration and renal disease in glycogen storage disease, type I

    Get PDF
    Hyperfiltration and renal disease in glycogen storage disease, type I. A prospective study of 14 patients (ages 6 months to 33 years) with glycogen storage disease, Type I (GSD-I) was carried out in order to define the character and frequency of renal dysfunction. A marked increase in the glomerular filtration rate (GFR) was documented in virtually all subjects, with the mean GFR raised by approximately 50%, to the range of 170 ml/min/1.73m2. While this constituted the only renal abnormality found in the younger patients, a significant increase in urinary albumin excretion was seen in three teen-aged individuals; three patients over 20 years of age exhibited frank proteinuria (2 to 8 g/day). Renal biopsy on two of the proteinuric subjects revealed focal and global glomerulosclerosis and interstitial fibrosis. Evaluation of factors known to cause an increase in GFR did not define the precise etiology for its elevation in GSD-I. These studies suggest that: (1) glomerular damage and chronic renal disease are common in older patients with GSD-I; (2) the renal injury appears to be specifically related to GSD-I and is not secondary to the treatment of the disease; and (3) the natural history of the renal lesion in GSD-I may be analogous to that seen in insulin-dependent diabetes, with a “silent” period where hyperfiltration is the only demonstrable renal abnormality, followed by evidence of increasing glomerular damage progressing from microalbuminuria to frank proteinuria

    Sex Differences in the Association Between Cumulative Use of Cannabis and Cognitive Function in Middle Age: The Coronary Artery Risk Development in Young Adults Study.

    Get PDF
    Background: Cannabis use may impair cognitive function (CF) differently in men and women, due to sex-specific differences in neurobiological mechanisms and environmental risk factors. Objective: Assess sex differences in the association between cumulative exposure to cannabis and cognitive performance in middle age. Methods: We studied participants from the Coronary Artery Risk Development in Young Adults (CARDIA) Study, including Black and White men and women 18-30 years old at baseline followed over 30 years. Our cross-sectional analysis of CF scores at year 30 was stratified by sex. We computed categories of cumulative exposure in "cannabis-years" (1 cannabis-year=365 days of use) from self-reported use every 2 to 5 years over 30 years. At years 25 and 30, we assessed CF with the Rey Auditory Verbal Learning Test (verbal memory), the Digit Symbol Substitution Test (processing speed), and the Stroop Interference Test (executive function). At year 30, additional measures included Category and Letter Fluency Test (verbal ability) and the Montreal Cognitive Assessment (global cognition). We computed standardized scores for each cognitive test and applied multivariable adjusted linear regression models for self-reported cumulative cannabis use, excluding participants who used cannabis within 24 h. In a secondary analysis, we examined the association between changes in current cannabis use and changes in CF between years 25 and 30. Results: By year 30, 1,352 men and 1,793 women had measures of CF; 87% (N=1,171) men and 84% (N=1,502) women reported ever cannabis use. Men had a mean cumulative use of 2.57 cannabis-years and women 1.29 cannabis-years. Self-reported cumulative cannabis use was associated with worse verbal memory in men (e.g., -0.49 standardized units [SU] for ≥5 cannabis-years of exposure; 95% CI=-0.76 to -0.23), but not in women (SU=0.02; 95% CI=-0.26 to 0.29). Other measures of CF were not associated with cannabis. Changes in current cannabis use between years 25 and 30 were not associated with CF in men or women. Conclusions: Self-reported cumulative cannabis exposure was associated with worse verbal memory in men but not in women. Researchers should consider stratified analyses by sex when testing the association between cannabis and cognition

    The Metabolic Syndrome Is Associated With Lower Cognitive Performance and Reduced White Matter Integrity in Midlife: The CARDIA Study

    Get PDF
    BackgroundCardiovascular disease risk factors play a critical role in brain aging. The metabolic syndrome (MetS), a constellation of cardiovascular risk factors, has been associated with poorer cognition in old age; however, it is unclear if it is connected to brain health earlier in life.MethodsWe investigated the association of MetS (n = 534, 18.5%) vs. no MetS (n = 2,346, 81.5%) with cognition in midlife within the prospective study, Coronary Artery Risk Development in Young Adults (CARDIA). At midlife (mean age 50), MetS was defined using National Cholesterol Education Program guidelines. At the 5-year follow-up, a cognitive battery was administered including tests of processing speed (Digit Symbol Substitution Test, DSST), executive function (the Stroop Test), verbal memory (Rey Auditory Verbal Learning Test, RAVLT), verbal fluency (category and letter fluency), and global cognitive function (Montreal Cognitive Assessment, MoCA). A sub-sample (n = 453) underwent brain MRI.ResultsParticipants with MetS had worse performance on tests of verbal fluency, processing speed, executive function, and verbal memory (p < 0.05), but not on global cognition. MetS was also associated with lower frontal, parietal, temporal, and total white matter integrity (p < 0.05), as assessed with fractional anisotropy.ConclusionsMetS is associated with lower cognition and microstructural brain alterations already at midlife, suggesting that MetS should be targeted earlier in life in order to prevent adverse brain and cognitive outcomes

    An ontology for immune epitopes: application to the design of a broad scope database of immune reactivities

    Get PDF
    BACKGROUND: Epitopes can be defined as the molecular structures bound by specific receptors, which are recognized during immune responses. The Immune Epitope Database and Analysis Resource (IEDB) project will catalog and organize information regarding antibody and T cell epitopes from infectious pathogens, experimental antigens and self-antigens, with a priority on NIAID Category A-C pathogens () and emerging/re-emerging infectious diseases. Both intrinsic structural and phylogenetic features, as well as information relating to the interactions of the epitopes with the host's immune system will be catalogued. DESCRIPTION: To effectively represent and communicate the information related to immune epitopes, a formal ontology was developed. The semantics of the epitope domain and related concepts were captured as a hierarchy of classes, which represent the general and specialized relationships between the various concepts. A complete listing of classes and their properties can be found at . CONCLUSION: The IEDB's ontology is the first ontology specifically designed to capture both intrinsic chemical and biochemical information relating to immune epitopes with information relating to the interaction of these structures with molecules derived from the host immune system. We anticipate that the development of this type of ontology and associated databases will facilitate rigorous description of data related to immune epitopes, and might ultimately lead to completely new methods for describing and modeling immune responses

    Hubble Space Telescope WFPC-2 Imaging of Cassiopeia A

    Get PDF
    The young SNR Cassiopeia A was imaged with WFPC-2 through four filters selected to capture the complete velocity range of the remnant's main shell in several important emission lines. Primary lines detected were [O III] 4959,5007, [N II] 6583, [S II] 6716,6731 + [O II] 7319,7330 + [O I] 6300,6364, and [S III] 9069,9532. About 3/4th of the remnant's main shell was imaged in all four filters. Considerable detail is observed in the reverse-shocked ejecta with typical knot scale lengths of 0.2"-0.4" (1 - 2 x 10^16 cm). Both bright and faint emission features appear highly clumped. Large differences in [S III] and [O III] line intensities indicating chemical abundance differences are also seen, particularly in knots located along the bright northern limb and near the base of the northeast jet. A line of curved overlapping filament in the remnant's northwestern rim appears to mark the location of the remnant's reverse shock front in this region. Finger-like ejecta structures elsewhere suggest cases where the reverse shock front is encountering the remnant's clumped ejecta. Narrow-band [N II] images of the remnant's circumstellar knots ("QSFs") reveal them to be 0.1"-0.6" thick knots and filaments, often with diffuse edges facing away from the center of expansion. Three color composite images of the whole remnant and certain sections along with individual filter enlargements of selected regions of the bright optical shell are presented and discussed.Comment: 26 pages, 12 figures Accepted to the Astronomical Journa
    corecore