Preserved Capacity for Adaptations in Strength and Muscle Regulatory Factors in Elderly in Response to Resistance Exercise Training and Deconditioning.

Aging is related to an inevitable loss of muscle mass and strength. The mechanisms behind age-related loss of muscle tissue are not fully understood but may, among other things, be induced by age-related differences in myogenic regulatory factors. Resistance exercise training and deconditioning offers a model to investigate differences in myogenic regulatory factors that may be important for age-related loss of muscle mass and strength.

Progression of cardiac involvement in patients with limb-girdle type 2 and Becker muscular dystrophies: a 9-year follow-up study.

Aim: To assess the degree and progression of cardiac involvement in patients with limb-girdle type 2 (LGMD2) and Becker muscular dystrophies (BMD).

Methods: A follow-up study of 100 LGMD2 (types A-L) and 30 BMD patients assessed by electrocardiogram (ECG) and echocardiography, supplemented by Holter-monitoring at follow-up.

Results: After a median of 8.

Quantitative magnetic resonance imaging in limb-girdle muscular dystrophy 2I: a multinational cross-sectional study.

We conducted a prospective multinational study of muscle pathology using magnetic resonance imaging (MRI) in patients with limb-girdle muscular dystrophy 2I (LGMD2I). Thirty eight adult ambulant LGMD2I patients (19 male; 19 female) with genetically identical mutations (c.826C>A) in the fukutin-related protein (FKRP) gene were recruited.

Quantitative muscle MRI as an assessment tool for monitoring disease progression in LGMD2I: a multicentre longitudinal study.

Background: Outcome measures for clinical trials in neuromuscular diseases are typically based on physical assessments which are dependent on patient effort, combine the effort of different muscle groups, and may not be sensitive to progression over short trial periods in slow-progressing diseases. We hypothesised that quantitative fat imaging by MRI (Dixon technique) could provide more discriminating quantitative, patient-independent measurements of the progress of muscle fat replacement within individual muscle groups.

Objective: To determine whether quantitative fat imaging could measure disease progression in a cohort of limb-girdle muscular dystrophy 2I (LGMD2I) patients over a 12 month period.

Creatine kinase response to high-intensity aerobic exercise in adult-onset muscular dystrophy.

Introduction: We investigated the effect of high-intensity exercise on plasma creatine kinase (CK) in patients with muscular dystrophies.

Methods: Fourteen patients with Becker (BMD), facioscapulohumeral (FSHD), or limb-girdle type 2 (LGMD2) muscular dystrophy, and 8 healthy subjects performed 5 cycling tests: an incremental max test, and tests at 65%, 75%, 85%, and 95% of maximal oxygen uptake (VO2max ). Heart rate and oxygen consumption were measured during the tests, and plasma CK was measured before, immediately after, and 24 hours after exercise.

Resistance training in patients with limb-girdle and becker muscular dystrophies.

Introduction: In this study we investigated the effect of strength training in patients with limb-girdle muscular dystrophy (LGMD) and Becker muscular dystrophy (BMD).

Methods: In 2 studies we compared the effect of low-intensity training (LOIT; n = 8) and high-intensity training (HIT; n = 4) in muscles of the upper and lower extremities. Patients were tested for maximal strength and endurance before and after the training program.

Calpain 3 is important for muscle regeneration: evidence from patients with limb girdle muscular dystrophies.

Background: Limb girdle muscular dystrophy (LGMD) type 2A is caused by mutations in the CAPN3 gene and complete lack of functional calpain 3 leads to the most severe muscle wasting. Calpain 3 is suggested to be involved in maturation of contractile elements after muscle degeneration. The aim of this study was to investigate how mutations in the four functional domains of calpain 3 affect muscle regeneration.

Level of muscle regeneration in limb-girdle muscular dystrophy type 2I relates to genotype and clinical severity.

Background: The balance between muscle regeneration and ongoing degeneration is a relationship that greatly influences the progression of muscular dystrophy. Numerous factors may influence the muscle regeneration, but more information about the relationship between genotype, clinical severity and the ability to regenerate is needed.

Methods: Muscle biopsies were obtained from the tibialis anterior muscle, and frozen sections were stained for general histopathological and immunohistological evaluation.

Effect of changes in fat availability on exercise capacity in McArdle disease.

Background: The major fuel for exercising muscle at low exercise intensities is fat.

Objective: To investigate the role of fat metabolism in McArdle disease (also known as glycogen storage disease type V), an inborn error of muscle glycogenolysis, by manipulating free fatty acid availability for oxidation during exercise.

Design: Randomized, placebo-controlled, crossover trial.

Endurance training improves fitness and strength in patients with Becker muscular dystrophy.

Studies in a dystrophinopathy model (the mdx mouse) suggest that exercise training may be deleterious for muscle integrity, but exercise has never been studied in detail in humans with defects of dystrophin. We studied the effect of endurance training on conditioning in patients with the dystrophinopathy, Becker muscular dystrophy (BMD). Eleven patients with BMD and seven matched, healthy subjects cycled 50, 30 min sessions at 65% of their maximal oxygen uptake (VO(2max)) over 12 weeks, and six patients continued cycling for 1 year.

cDNA analyses of CAPN3 enhance mutation detection and reveal a low prevalence of LGMD2A patients in Denmark.

Calpainopathy or limb-girdle muscular dystrophy type 2A (LGMD2A) is generally recognized as the most prevalent form of recessive LGMD and is caused by mutations in the CAPN3 gene. Out of a cohort of 119 patients fulfilling clinical criteria for LGMD2, referred to our neuromuscular clinic, 46 were suspected to have LGMD2A, based on western blot results. Four of these patients were shown to have LGMD2I upon molecular analysis, whereas 16 of the remaining 42 patients harbored mutations in CAPN3 by both direct genomic sequencing and cDNA analyses.

High prevalence and phenotype-genotype correlations of limb girdle muscular dystrophy type 2I in Denmark.

Objectives: The prevalence of limb girdle muscular dystrophy type 2I (LGMD2I) in northern Europe is unknown. We investigated this and the genotype-phenotype relation in LGMD2I.

Methods: Prospective clinical and molecular screening of 118 Danish patients registered with LGMD was performed to divide patients into LGMD subtypes.

LGMD2I presenting with a characteristic Duchenne or Becker muscular dystrophy phenotype.

LGMD type 2I, caused by mutations in the fukutin-related protein, is a common form of LGMD. The phenotype resembles Duchenne/Becker muscular dystrophy. A point mutation, L276I has been found in all patients with LGMD2I studied so far.

No effect of MDMA (ecstasy) on cell death and 5-HT2A receptor density in organotypic rat hippocampal cultures.

MDMA (3,4 Methylenedioxy-methamphetamine) binds and blocks the presynaptic serotonin reuptake transporters and postsynaptic serotonin 5-HT2A receptors, with highest affinity for the first. Whether 5-HT2A receptor density decreases due to MDMA's direct effect on postsynaptic serotonin receptors is at present not known. This study analyzes whether direct stimulation of the postsynaptic 5-HT2A receptor by MDMA in organotypic hippocampal cultures results in cell death and downregulation of this receptor.