摘要:

AbstractLysosomal changes of mouse skeletal muscle during the repair of exercise injuries were studied with biochemical, histochemical, and electron microscopic methods. Treadmill running for 4 hours and 9 hours increased the activities of cathepsin C and β‐glucuronidase, but not that of β‐glycerophosphatase in mouse quadriceps femoris muscle. The highest activities occurred 3 days after exertion and were higher after the longer duration of exertion. Similar changes that were highly correlated with the activities of lysosomal enzymes occurred in the activities of glucose‐6‐phosphate dehydrogenase and 6‐phosphogluconate dehydrogenase and in the concentration of DNA. The activities of lysosomal enzymes correlated significantly with the severity of histopathologic injuries. Histochemical stainings of β‐N‐acetylglucosaminidase and β‐glucuronidase showed a strong increase in the staining intensity 3 and 5 days after exertion, both in inflammatory phagocytes and in surviving muscle fibers in the injured area, and staining intensities increased in parallel with the severity of injuries. Electron microscopy showed an increased number of autophagic vacuoles, lysosomelike bodies, and Golgi complexes in the fibers adjacent to necrotic foci, coinciding with the highest histochemical staining pattern. Lysosomal changes in surviving muscle fibers in close proximity to injured muscle fibers could, by autophagic degradation, provide structural elements for the regeneration of in

ISSN:0148-639X    

DOI:10.1002/mus.880080402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThis study describes immunocytochemical changes in laminin, which is an integral basement membrane (BM) component, during axonal regeneration through antigenic nerve allografts and nonantigenic nerve isografts. In normal rat nerve, laminin was localized in the BM of Schwann cells and the perineurium. During nerve allograft rejection, the perineurium and Schwann cells disappeared. However, the Schwann cell BMs persisted and became distorted and collapsed. In isografted nerves, the perineurium and Schwann cells were present, and only a few Schwann cell BMs appeared to be distorted; however, the staining for laminin was faint, indicating a possible BM breakdown. A new BM appeared as small rings around the Schwann cells after they had become associated with regenerated axons. Because only a limited axonal regeneration occurred in allografts as compared to isografts, it is concluded that the viable Schwann cells, and their BM architecture, are essential for regeneration through long nerve grafts.

ISSN:0148-639X    

DOI:10.1002/mus.880080403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe effects of inspiratory resistive training on respiratory muscle function was evaluated in 11 patients with Duchenne, limb‐girdle, and facioscapulo‐humeral (FSH) type muscular dystrophy. Muscle training consisted of breathing against an inspiratory resistance for two 15‐minute sessions each day while at home. Following 6 weeks of training, there were significant increases in the maximum resistance that could be tolerated for at least 5 minutes (P<0.01) and also in the maximum duration that ventilations equal to 30%, 50%, 70%, and 90% of the maximum voluntary ventilation could be sustained (P<0.05). In six patients who trained for an additional 6‐week period, respiratory muscle endurance increased even further. The degree of improvement in respiratory muscle endurance was positively correlated with baseline vital capacity (r= 0.84,P<0.05) and maximal inspiratory pressure (r= 0.76,P<0.05). Spirometry, functional residual capacity, and maximal inspiratory and expiratory pressures were not affected by training. We conclude that inspiratory resistive training improves respiratory muscle endurance in muscular dystrophy patients. Improvement in respiratory muscle function may serve to delay the onset of respiratory complications in patients with muscular dy

ISSN:0148-639X    

DOI:10.1002/mus.880080404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractWe have studied four members of a family in which five individuals of both sexes in three generations have mild weakness and muscle aching. Serum creatine kinase (CK) and/or aldolase were mildly to moderately elevated. Tubular aggregates were present in all patients in all fiber types. Type 1 fiber predominance and type 2 hypotrophy or atrophy was noted in three biopsies. Fiber splitting was prominent in two cases. Electron microscopic studies confirm that the tubular aggregates originate from muscle sarcoplasmic reticulum (SR). The presence of T tubules making contacts with some tubules inside the collection of tubular aggregates is suggestive of their derivation from terminal cisternae.

ISSN:0148-639X    

DOI:10.1002/mus.880080405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractMuscle biopsy specimens from three patients with an autosomal dominant myopathy and tubular aggregates in both type 1 and type 2 fibers16were investigated for immunofluorescent staining with antibodies to sarcoplasmic reticulum (SR) Ca‐pump protein and calsequestrin and for Ca2+loading ability. The results show that type 1 and type 2 fibers are differentially reactive to anti–ca‐pump protein lgG and similarly reactive with affinity‐purified antibody to calsequestrin, which is in agreement with earlier observations in rat skeletal muscle.8Tubular aggregates, which are shown to be highly reactive with either kind of antibody, appear to be sites of calcium accumulation for oxalatefacilitated adenosine triphosphate (ATP) dependent Ca uptake by chemically skinned fibers and thereby increase markedly the Ca loading capacity of the affected

ISSN:0148-639X    

DOI:10.1002/mus.880080406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractA monoclonal antibody directed against a slow isoform of a 100‐K myofibrillar protein has been used to study the differentiation of muscle fibers in the fast and slow muscles of the rat. Immunohistochemical studies have shown that initiation of differentiation into fast and slow muscle fibers occurs very early during development. The distribution pattern of cell types in different muscles is unique and is also determined very early during fetal muscle development. It is concluded that motor innervation is probably not essential to initiate differentiation into distinct muscle fiber type

ISSN:0148-639X    

DOI:10.1002/mus.880080407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractAn increased cellular Ca2+content has been associated with Duchenne muscular dystrophy (DMD). However, estimates of the free cytoplasmic Ca2+concentration ([Ca2+]i) in cells of DMD patients were not available. We compared the [Ca2+]i levels of normal and DMD peripheral blood lymphocytes and Epstein‐Barr virus‐transformed lymphoblasts using the novel probe, quin 2, an internally trapped fluorescent indicator. The [Ca2+]i levels of normal and DMD cells were not significantly differ

ISSN:0148-639X    

DOI:10.1002/mus.880080408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractEleven consecutive patients with progressive chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) underwent plasma exchange. Eight patients were previously unresponsive to prednisone, two were started on prednisone with plasma exchange, and one did not receive corticosteroids. Electrodiagnostic studies revealed evidence of an acquired demyelinating polyradiculoneuropathy with varying degrees of axonal degeneration. Neurologic impairment was monitored using conventional functional status index. Five patients demonstrated substantial clinical improvement, beginning 2 days to 3 weeks after initiating plasma exchange. Two additional patients improved following a second course of plasma exchange, and four patients demonstrated minimal or no change. Comparison of responding and onresponding patients showed no differences related to the presence or absence of antecedent illness, duration of disease, duration of maximum weakness, or severity of impairment prior to plasma exchange. Responders had significantly prolonged F‐response and motor distal latencies compared to nonresponders. Results in this unselected, consecutive patient trial suggest a temporal relationship between plasma exchange and clinical improvement in some patients with progressive CID

ISSN:0148-639X    

DOI:10.1002/mus.880080409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractTwenty patients with myasthenia gravis were studied. Needle interference patterns at maximal isometric contractions were recorded from the biceps brachii muscles. Each recording lasted for 30 seconds and induced som fatigue. The EMG signals were transformed into power spectra and were analyzed for differences between control and myasthenic fatigue trends and were tested for the power of the frequency variables to classify unknown subjects. Both groups showed a similar averaged spectra for the first 5 seconds. Thereafter, the controls manifested continuous increase in power, and a power peak frequency shift toward low frequencies. The myasthenics showed an initial increase throughout the frequency ranges; however, later, there was a marked decrease in power and their peak frequency shifted toward the lower frequencies. These fatigue trends differed significantly from one another. Discriminant analysis correctly classified 83% of the subjects. This technique may be helpful in the diagnosis of myasthenia gravis.

ISSN:0148-639X    

DOI:10.1002/mus.880080410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe binding of rabies virus to cellular membranes was measured using an enzyme‐linked immunosorbent assay (ELISA). Virus binding to membranes adsorbed to the wells of microtiter plates was detected with rabies virus antibody and alkaline phosphatase‐linked second antibody. The greatest degree of binding was to myotube, neuroblastoma, and salivary gland membranes; intermediate levels occurred in striated muscle and nerve membranes; and low levels of binding were found in other membranes, including those of most parenchymal organs. Binding of rabies virus to myotube membranes was saturable, dependent on pH (with an optimum of pH 6.0), facilitated by the divalent cations Ca++, Mn++, and Mg++, and was temperature dependent. Binding was greatly reduced by inactivation of virus with β‐propiolactone or treatment of virus with trypsin. In embryonic chick myotubes, total acetylcholine receptor content and acetylcholinesterase activity undergo marked changes during development, first increasing and then decreasing at the time of hatching. Binding of rabies virus followed a similar pattern, indicating that the virus may interact with the acetylcholine receptor or other surface molecules undergoing similar developmental c

ISSN:0148-639X    

DOI:10.1002/mus.880080411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY