Publications by authors named "Jan Henriksson"

The aim of the study was to explore the long- and short-axis dimensions, shape and collapsibility of the inferior vena cava in 46 trained and 48 untrained females (mean age: 21 ± 2 y). Echocardiography in the subcostal view revealed a larger expiratory long-axis diameter (mean: 24 ± 3 vs. 20 ± 3 mm, p < 0.

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Regular physical activity affects most organs and tissues through a large number of mechanisms which in various ways contribute to improved function and health. Regular physical activity improves quality of life, cognitive functions, mood state and physical capacity, and lowers the risk of many diseases and premature death. Physical activity affects proteins and gene expression through signalling mechanisms, e.

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Objective: To evaluate gait in patients with post-polio syndrome, using the 6-minute walk test (6MWT) combined with three-dimensional kinematic analysis.

Design: Descriptive study.

Subjects: Eighteen patients and 11 healthy controls.

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Purpose: Based on previous evidence of muscle fiber injury and decreased blood flow in the extensor carpi radialis brevis (ECRB) muscle in lateral epicondylitis (LE), we hypothesized that there would also be an abnormal (vasoconstrictive) vascular response to adrenaline in the ECRB muscle in LE.

Methods: In a case-control study, we measured skeletal muscle blood flow in 8 patients with LE and in 8 healthy controls in response to a 30-minute intravenous infusion of adrenaline. We used local clearance of technetium-99m in the main portion of the ECRB muscle to calculate muscle blood flow.

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Phospholemman (PLM, FXYD1) is a partner protein and regulator of the Na(+)-K(+)-ATPase (Na(+)-K(+) pump). We explored the impact of acute and short-term training exercise on PLM physiology in human skeletal muscle. A group of moderately trained males (n = 8) performed a 1-h acute bout of exercise by utilizing a one-legged cycling protocol.

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The study tested the hypothesis that vestibular patients (n=14) with chronic unsteadiness caused by a documented peripheral unilateral vestibular dysfunction would display differences in muscular activation and movement pattern during gait initiation compared to age-, gender- and body-size-matched healthy Controls (n=14). The displacements of the whole body Center of Pressure (CoP) during the preparatory phase before the swing leg is lifted, were markedly different in vestibular patients. The backward shift during this phase was significantly smaller than in Controls, coupled with a larger secondary corrective forward shift of the CoP.

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Aim: To test if a small muscle injury influences the vascular reactivity to adrenaline in human skeletal muscle.

Methods: Blood flow was measured by ¹³³Xenon clearance in the gastrocnemius muscle of eight male subjects at basal and during i.v.

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The primary aim of our study was to validate the assessment of myonuclear and satellite cell number in biopsies from human skeletal muscle. We found that 25 type I and 25 type II fibers are sufficient to estimate the mean number of myonuclei per fiber. In contrast, the assessment of satellite cells improved when more fibers were included.

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Aim: To find evidence that small changes in the positioning of the strain gauge, the environmental temperature (sympathetic activation) and position of the arm (venous pressure) alters the outcome of the venous occlusion plethysmography (VOP) measurement of forearm blood flow and to investigate if the hand circulation influences the results.

Methods: Forearm blood flow was measured with VOP (n = 6) on three occasions with air temperatures of 13, 20 and 38 degrees C, respectively. At each occasion the arm position was varied; raised by 10 degrees , horizontal or lowered by 15 degrees .

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The aim of this investigation was to study the distribution of satellite cells in slow (type I fibres) and fast (type II fibres) fibres from human vastus lateralis muscle. This muscle is characterised by a mixed fibre type composition and is considered as the site of choice for biopsies in research work and for clinical diagnosis. Biopsy samples were obtained from five healthy young volunteers and a total of 1,747 type I fibres and 1,760 type II fibres were assessed.

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Background: Three efficacy studies, comprising a database of 337 subjects, were conducted as part of the clinical evaluation of the noninjectable anesthetic gel Oraqix (AstraZeneca, Södertälje, Sweden). The authors discuss some of the challenges encountered when they interpreted the results of the clinical studies and present the results from an alternative analysis of the anesthetic efficacy.

Methods: The three multicenter studies were double-blind, randomized and placebo-controlled.

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The objective of this study was to investigate the cellular localisation of MyoD and myogenin in human skeletal muscle fibres as well as the possible alterations in the expression of MyoD and myogenin in response to a single bout of endurance exercise at 40% and 75% of maximum oxygen uptake (VO(2) max). Twenty-five biopsies (5 per subject) from the vastus lateralis muscle were obtained before exercise, from the exercising leg at 40% and 75% of VO(2) max and from the resting leg following these exercise bouts. The tyramide signal amplification-direct and the Vectastain ABC methods using specific monoclonal antibodies were used to determine the exact location of myogenin and MyoD, to identify muscle satellite cells and to determine myosin heavy chain (MyHC) composition.

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We determined whether protein kinase C (PKC) isoforms are redistributed and phosphorylated in response to acute exercise in skeletal muscle. Muscle biopsies were obtained from six healthy subjects (four women, two men; age 25 +/- 1 years) before, during, and after 60 min of one-leg cycle ergometry at approximately 70% VO(2peak). Exercise for 30 and 60 min was associated with a three- and fourfold increase in PKC-zeta/lambda abundance and a four- and threefold increase in phosphorylation, respectively, in total membranes (P < 0.

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Trypanosoma cruzi is thought to undergo predominant clonal evolution, as determined by population genetics studies. However, this model does not exclude occasional recombination, which existence is strongly suggested by several recent studies. We sequenced a portion of the maxicircle cytochrome b (CYb) gene and of the nuclear rRNA promoter region from representative strains of six T.

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Blood flow determinations by venous occlusion plethysmography applying the strain-gauge technique are frequently used. A problem with the strain-gauge technique is that the relationship between venous volume and transmural pressure is not linear and, furthermore, changes with the sympathetic tone. The present study tests the hypothesis that these factors lead to a redistribution of venous blood, which may impair the accuracy of the technique.

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