Search results for "Muscle fibre"
showing 10 items of 23 documents
Adult polyglucosan body myopathy.
1992
This report describes a sporadic late-onset myopathy in two unrelated adults which was marked by polyglucosan inclusions surrounded by abnormally structured mitochondria, the latter finding a localized, possibly reactive phenomenon. The polyglucosan material was characterized by a battery of histochemical and enzyme histochemical techniques; revealed common antigenicity with Lafora bodies, corpora amylacea and muscle fiber inclusions in types IV and VII glycogenoses; and contained ubiquitin. Additional lectin histochemical and associated digestion preparations disclosed the presence of alpha-glycosyl residues as apparently the sole carbohydrate component in polyglucosan bodies while the abo…
Controlled intermittent shortening contractions of a muscle-tendon complex: muscle fibre damage and effects on force transmission from a single head …
2005
This study was performed to examine effects of prolonged (3 h) intermittent shortening (amplitude 2 mm) contractions (muscles were excited maximally) of head III of rat extensor digitorum longus muscle (EDL III) on indices of muscle damage and on force transmission within the intact anterior crural compartment. Three hours after the EDL III exercise, muscle fibre damage, as assessed by immunohistochemical staining of structural proteins (i.e. dystrophin, desmin, titin, laminin-2), was found in EDL, tibialis anterior (TA) and extensor hallucis longus (EHL) muscles. The damaged muscle fibres were not uniformly distributed throughout the muscle cross-sections, but were located predominantly ne…
Relationships between muscle fibre characteristics and physical performance capacity in trained athletic boys
1991
The relationships between muscle fibre characteristics and the physical performance capacity of trained athletic boys (aged 11-13 years) were studied over 2 days. The subjects were divided into two groups according to muscle fibre distribution. The 'fast' group (FG) comprised 10 subjects (sprinters, weightlifters, tennis players) with more than 50% fast-twitch fibres (type II), and the 'slow' group (SG) comprised 8 subjects (endurance runners, tennis players, one weightlifter) with more than 50% slow-twitch fibres (type I) in their vastus lateralis muscle. The 'fast' group had 59.2 +/- 6.3% and the 'slow' group had 39.4 +/- 9.8% type II fibres. Other clear differences (P less than 0.05-0.01…
Pathogenesis of Anterior Knee Pain in the Active Young: Is There a Relation Between the Presence of Patellofemoral Malalignment and Pain?
2012
This chapter is not intended to advocate for a particular surgical technique, but it does provide insight into improving our understanding of the pathophysiology of anterior knee pain syndrome. Our objectives were: to identify a relationship, or lack of one, between the presence of PFM and the presence of anterior knee pain; to analyze the long-term response of VMO muscle fibers to increased resting length; and to determine the incidence of patellofemoral osteoarthritis after IPR surgery. Our findings indicate (1) that not all PFM knees show symptoms; that is, PFM is not a sufficient condition for the onset of symptoms, at least in postoperative patients; (2) that the advancement of VMO has…
Value of insoluble PABPN1 accumulation in the diagnosis of oculopharyngeal muscular dystrophy.
2019
Background and purpose The aim was to assess the value of insoluble PABPN1 muscle fibre nuclei accumulation in the diagnosis of atypical cases of oculopharyngeal muscular dystrophy (OPMD). Methods Muscle biopsies from a selected cohort of 423 adult patients from several Italian neuromuscular centres were analysed by immunofluorescence: 30 muscle biopsies of genetically proven OPMD, 30 biopsies from patients not affected by neuromuscular disorders, 220 from genetically undiagnosed patients presenting ptosis or swallowing disturbances, progressive lower proximal weakness and/or isolated rimmed vacuoles at muscle biopsy and 143 muscle biopsies of patients affected by other neuromuscular diseas…
Morphology of cardiac muscle in septic shock. Observations with a porcine septic shock model.
1995
The morphology of cardiac muscle was investigated in a porcine model of septic shock, created by intermitted application of Escherichia coli-endotoxin. The earliest lesions, found after 18 h of septic shock, were endothelial cell swelling, marked leucostasis and slight ischaemic alterations of the muscle fibres. At the end point of the experiments, after 48 h, some fibrin thrombi were found associated with more pronounced ischaemic alterations of cardiac muscle cells and some necrotic fibres. Comparing these findings with the severe endothelial and muscle fibre lesions found in skeletal muscle, the endothelial cells of the heart microvasculature, are clearly more resistant to the attack of …
121st ENMC International Workshop on Desmin and Protein Aggregate Myopathies. 7–9 November 2003, Naarden, The Netherlands
2004
The 121st European Neuromuscular Centre (ENMC)sponsored International Workshop on ‘DESMIN and Protein Aggregate Myopathies’, attended by 16 active participants from France, Germany, Poland, Spain, Sweden, the United Kingdom and the USA, was actually the fourth one in a row addressing the pathology of the muscle fibre intermediate filament desmin, its associated and similar diseases, all four [1–3] organized by Michel Fardeau and Hans H. Goebel. In his introduction, the chairman, Hans H. Goebel (Mainz), recorded the evolution of ‘Protein Aggregate Myopathies (PAM)’ which are marked by the accumulation of diverse proteins within muscle fibres as a morphologic hallmark in separate myopathies w…
Versuche zur Bestimmung des wahren K-Efflux im Rattenzwerchfell
1960
In an isolated muscle loaded with 42K the potassium efflux through the muscle fibre membrane can be calculated from the rate constant of the loss of 42K into an inactive bathing solution. The calculation can only be valid if the amount of 42K leaving all the individual fibres is equivalent to the amount of 42K entering the bathing solution from the surface of the whole muscle. It seems possible that 42K ions which have already left a muscle cell can be taken up again into a muscle fibre before diffusing into the bathing solution. Thus the calculated potassium efflux might be smaller than the real efflux.
Role of geometry and anisotropic diffusion for modelling PO2 profiles in working red muscle
1990
A 3-dimensional analytical model of O2 diffusion in heavily working muscle is proposed which considers anisotropic, myoglobin (Mb)-facilitated O2 diffusion inside the muscle fiber and a carrier-free layer separating erythrocytes and fiber. The model is used to study the effects of some commonly applied simplifying assumptions (reduced dimensionality, neglected anisotropy) on the resulting PO2 distributions: (1) In order not to underestimate PO2 drops near erythrocytes, modelling O2 transport in 3 dimensions is important. (2) For a capillary-to-fiber ratio of 1, the results from the 2-dimensional version of the present model and from a Krogh-type model which incorporates a carrier-free layer…
Effect of training on aerobic capacity of female athletes differing in muscle fibre composition
1983
Abstract The effects of endurance training were studied in two groups of female cross‐country skiers who differed in muscle fibre composition. The ST‐group (n = 10) had 56–76% slow twitch (ST) muscle fibres and the FT‐group (n= 10) 40–55% ST fibres in the m. vastus lateralis. During a four‐month period, the subjects trained on the average 81 km per week. The intensive training (heart rate 0–15 beats per min below maximum) averaged 8.5 km per week. The differences in training between the two groups were not significant. The ST‐group significantly increased their cycling maximum oxygen uptake (C max, 4.6%, P <0.01) and the anaerobic threshold (AT, 2.8%, P <0.01) during the training period whe…