378 research outputs found
Measurement of resistance exercise force expression
This is the publisher's version, also found at http://ehis.ebscohost.com/ehost/detail?sid=afef5b5e-42ad-4a92-896e-f02e050a2011%40sessionmgr10&vid=1&hid=17&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=s3h&AN=13021242Displacement-based measurement systems are becoming increasingly popular
for assessment of force expression variables during resistance exercise.
Typically a linear position transducer (LPT) is attached to the barbell to measure
displacement and a double differentiation technique is used to determine
acceleration. Force is calculated as the product of mass and acceleration. Despite
the apparent utility of these devices, validity data are scarce. To determine
whether LPT can accurately estimate vertical ground reaction forces,
two men and four women with moderate to extensive resistance training experience
performed concentric-only (CJS) and rebound (RJS) jump squats, two
sessions of each type in random order. CJS or RJS were performed with 30%,
50%, and 70% one-repetition maximum parallel back squat 5 minutes following
a warm-up and again after a 10-min rest. Displacement was measured via
LPT and acceleration was calculated using the finite-difference technique. Force
was estimated from the weight of the lifter-barbell system and propulsion force
from the lifter-barbell system. Vertical ground reaction force was directly
measured with a single-component force platform. Two-way random average-
measure intraclass correlations (ICC) were used to assess the reliability
of obtained measures and compare the measurements obtained via each method.
High reliability (ICC > 0.70) was found for all CJS variables across the loadspectrum.
RJS variables also had high ICC except for time parameters for
early force production. All variables were significantly (p < 0.01) related between
LPT and force platform methods with no indication of systematic bias.
The LPT appears to be a valid method of assessing force under these experimental
conditions
Myosin heavy chain isoform expression: Influence on isointertial and isometric performance
This is the publisher's version, also found at http://ehis.ebscohost.com/ehost/detail?vid=3&sid=c184ec76-77d8-4a98-bb1f-f5bceba902aa%40sessionmgr10&hid=2&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=s3h&AN=19495568Thirty-six healthy men with varying degrees of physical training background performed maximal-effort isometric and isoinertial knee extensor actions, with relative loads equal to 40% and 70% of one-repetition maximum. Force, velocity, and power were derived from force and linear position transducers at 500 Hz. Biopsies were taken from the vastus lateralis and analyzed by SDS-PAGE for relative myosin heavy chain (MHC) content. Relative MHC IIx content was included in a regression model, and explained variance noted. Relative MHC I content was subsequently added to the regression model to determine what, if any, additional variance was explained beyond that of MHC IIx. Results indicated that no relationship ( r = 0.0 to 0.1) exists between the relative expression of MHC isoforms from the vastus lateralis and isometric/isoinertial performance in a population with diverse training backgrounds. Lack of nervous system adaptations in the untrained subjects in the study possibly attenuates the significant relationship between MHC and in-vivo muscle performance previously established in trained populations. ABSTRACT FROM AUTHO
The burden of chronic obstructive pulmonary disease associated with maintenance monotherapy in the UK
Susan C Edwards,1 Sian E Fairbrother,2 Anna Scowcroft,3 Gavin Chiu,4 Andrew Ternouth,3 Brian J Lipworth5 1Department of Market Access Pricing & Outcomes Research, 2Department of Medical Affairs - Respiratory, 3Department of Market Access, 4Department of Prescription Medicine - Respiratory, Boehringer Ingelheim, Bracknell, UK; 5Asthma and Allergy Research Group, Division of Cardiovascular and Diabetes Medicine, Scottish Centre for Respiratory Research, University of Dundee, Ninewells Hospital and Medical School, Dundee, UK Background: This study characterized a cohort of chronic obstructive pulmonary disease (COPD) patients on maintenance bronchodilator monotherapy for ≥6 months to establish their disease burden, measured by health care utilization.Methods: Data were extracted from the UK Clinical Practice Research Datalink and linked to Hospital Episode Statistics. The monotherapy period spanned the first prescription of a long-acting β2-adrenergic agonist or a long-acting muscarinic antagonist until the end of the study (December 31, 2013) or until step up to dual/triple therapy, for example, addition of another long-acting bronchodilator, an inhaled corticosteroid, or both. A minimum of four consecutive prescriptions and 6 months on continuous monotherapy were required. Patients <50 years old at first COPD diagnosis or with another significant respiratory disease before starting monotherapy were excluded. Disease burden was evaluated by measuring patients’ rate of face-to-face interactions with a health care professional (HCP), COPD-related exacerbations, hospitalizations, and referrals.Results: A cohort of 8,811 COPD patients (95% Global initiative for chronic Obstructive Lung Disease stage A/B) on maintenance monotherapy was identified between 2002 and 2013; 45% of these patients were still on monotherapy by the end of the study. Median time from first COPD diagnosis to first monotherapy prescription was 56 days, while the median time on maintenance bronchodilator monotherapy was 2 years. The median number of prescriptions was 14. On average, patients had 15 HCP interactions per year, and one in ten patients experienced a COPD exacerbation (N=8,811). One in 50 patients were hospitalized for COPD per year (n=4,848).Conclusion: The average monotherapy-treated patient had a higher than average HCP interaction rate. We also identified a large cohort of patients who were stepped up to triple therapy despite a low rate of exacerbations. The use of the new class of long-acting muscarinic antagonist/long-acting β2-adrenergic agonist fixed-dose combinations may provide a useful step-up treatment option in such monotherapy patients, before the use of inhaled corticosteroids. Keywords: COPD, UK primary care setting, bronchodilators, prescribing patterns, monotherap
Agricultural Pesticide Use and Risk of t(14;18)-Defined Subtypes of Non-Hodgkin Lymphoma
Pesticides have been specifically associated with the t(14;18)(q32;q21) chromosomal translocation. To investigate whether the association between pesticides and risk of non-Hodgkin lymphoma (NHL) differs for molecular subtypes of NHL defined by t(14; 18) status, we obtained 175 tumor blocks from case subjects in a population-based case-control study conducted in Nebraska between 1983 and 1986. The t(14;18) was determined by interphase fluorescence in situ hybridization in 172 of 175 tumor blocks. We compared exposures to insecticides, herbicides, fungicides, and fumigants in 65 t(14;18)-positive and 107 t(14;18)-negative case subjects with those among 1432 control subjects. Multivariate polytomous logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Compared with farmers who never used pesticides, the risk of t(14;18)-positive NHL was significantly elevated among farmers who used animal insecticides (OR = 2.6; 95%CI, 1.0-6.9), crop insecticides (OR = 3.0; 95% CI, 1.1-8.2), herbicides (OR = 2.9; 95% CI, 1.1-7.9), and fumigants (OR = 5.0; 95% CI, 1.7-14.5). None of these pesticides were associated with t(14;18)-negative NHL. The risk of t(14;18)-positive NHL associated with insecticides and herbicides increased with longer duration of use. We conclude that insecticides, herbicides, and fumigants were associated with risk of t(14;18)-positive NHL but not t(14;18)-negative NHL. These results suggest that defining subsets of NHL according to t(14;18) status is a useful approach for etiologic research. (Blood. 2006; 108:1363-1369
Muscle fiber and performance adaptations to resistance exercise with MyoVive, colostrum or casein and whey supplementationa
This is the publisher's version, also found at http://ehis.ebscohost.com/ehost/detail?sid=ba69ee0d-97cf-4a2c-a1a2-2c26fb60d65c%40sessionmgr13&vid=1&hid=2&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=s3h&AN=10725638To determine the effects of 12 weeks of resistance exercise with MyoVive
and/or colostrum supplementation, 19 male and female recreationally weighttrained
subjects (X ± SE; age = 28.3 ± 6.9 yrs; hgt = 68.2 ± 3.8 cm) were
divided into MyoVive + colostrum (n = 4), MyoVive + casein & whey (n
= 4), colostrum + casein & whey (n = 6), and casein & whey (n = 5) groups.
All groups similarly increased (p < .05) 1 repetition maximum (RM) leg press
(kg; pre = 158.6 ± 12.8, post = 189.3 ± 11.3), body mass (kg; pre = 79.0 ±
3.2, post = 80.7 ± 3.8), and lean body mass (kg; pre = 60.1 ± 3.1, post = 62.2
± 2.8). Increases were observed for peak force (N; all loads), peak velocity
(m.s-1; 70% & 40% 1 RM), and peak power (W; 70% & 40% 1 RM) for all
groups for the leg press exercise, with no differences between groups. When
performance data were adjusted for body mass, lean body mass, lower body
lean mass as determined by DEXA, or % change, no group differences were
observed. Relative (%) fiber type content, cross-sectional areas (mm2), % fiber
type areas, or % myosin heavy chain expression did not change for any
group. These data suggest that MyoVive and colostrum supplementation
have no greater effect on cellular and performance adaptations when compared
to casein and whey protein
The Affective Impact of Financial Skewness on Neural Activity and Choice
Few finance theories consider the influence of “skewness” (or large and asymmetric but unlikely outcomes) on financial choice. We investigated the impact of skewed gambles on subjects' neural activity, self-reported affective responses, and subsequent preferences using functional magnetic resonance imaging (FMRI). Neurally, skewed gambles elicited more anterior insula activation than symmetric gambles equated for expected value and variance, and positively skewed gambles also specifically elicited more nucleus accumbens (NAcc) activation than negatively skewed gambles. Affectively, positively skewed gambles elicited more positive arousal and negatively skewed gambles elicited more negative arousal than symmetric gambles equated for expected value and variance. Subjects also preferred positively skewed gambles more, but negatively skewed gambles less than symmetric gambles of equal expected value. Individual differences in both NAcc activity and positive arousal predicted preferences for positively skewed gambles. These findings support an anticipatory affect account in which statistical properties of gambles—including skewness—can influence neural activity, affective responses, and ultimately, choice
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Pan-viral serology implicates enteroviruses in acute flaccid myelitis.
Since 2012, the United States of America has experienced a biennial spike in pediatric acute flaccid myelitis (AFM)1-6. Epidemiologic evidence suggests non-polio enteroviruses (EVs) are a potential etiology, yet EV RNA is rarely detected in cerebrospinal fluid (CSF)2. CSF from children with AFM (n = 42) and other pediatric neurologic disease controls (n = 58) were investigated for intrathecal antiviral antibodies, using a phage display library expressing 481,966 overlapping peptides derived from all known vertebrate and arboviruses (VirScan). Metagenomic next-generation sequencing (mNGS) of AFM CSF RNA (n = 20 cases) was also performed, both unbiased sequencing and with targeted enrichment for EVs. Using VirScan, the viral family significantly enriched by the CSF of AFM cases relative to controls was Picornaviridae, with the most enriched Picornaviridae peptides belonging to the genus Enterovirus (n = 29/42 cases versus 4/58 controls). EV VP1 ELISA confirmed this finding (n = 22/26 cases versus 7/50 controls). mNGS did not detect additional EV RNA. Despite rare detection of EV RNA, pan-viral serology frequently identified high levels of CSF EV-specific antibodies in AFM compared with controls, providing further evidence for a causal role of non-polio EVs in AFM
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