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M Moggio

Publications and source records attributed to M Moggio.

97 records · Page 6Linked to original sources

[Hypothyroid myopathy: histochemical and ultrastructural features with physiopatological correlations (author's transl)].

The Authors describe an adult case of hypothyroid myopathy which occurred after a Hashimoto's thyroiditis. Ultrastructural examination of the deltoid muscle showed two fundamental changes: 1) large collections of mitochondria generally normal in shape, structure and size, especially in the subsarcolemmal sapce of the muscle fibre; 2) glycogen deposits both beneath sarcolemmal membrane and between myofibrils. Histochemical examination reveals an increased activity of mitochondrial oxydative enzymes, such as NADPH and SDH especially in subsarcolemmal regions of many type I fibres. The histogram is normal. It seems that the multiplication of skeletal muscle mitochondria may be compensatory to the slowing down of metabolic activities. This, however, is ineffective because it involves the mitochondria localized more superficially in the fibres with a loosely coupled oxydative phosphorylation. Glycogen accumulations are probably due to deficiency of the thyroid hormone; in fact stimulation of carbohydrate metabolism by thyroxine is well known. The abnormal functioning of the muscular mitochondria and the defective utilisation of glycogen are the most important factors in the pathogenesis of muscular weakness of hypothyroid myopathy.

Adenosine Triphosphatases↗

A sporadic, atypical case of desminopathy: morphological and immunological characterization.

Recently, abnormal expression of cyclin-dependent kinases was proposed as a possible cause of desminopathy. We describe an atypical case clinically characterized by severe respiratory distress. Muscle biopsy showed subsarcolemmal and intracytoplasmic accumulation areas, which intensively stained with anti-desmin antibodies and contained electrondense filamentous material at ultrastructural level. WB analysis showed 30% increased desmin signal compared to controls. Positive immunostain for CDC2 kinase, CDK2 and emerin and nuclear matrix-associated protein were, found in desmin-positive fibres.

Adult↗

In vitro and in vivo tetracycline-controlled myogenic conversion of NIH-3T3 cells: evidence of programmed cell death after muscle cell transplantation.

Ex vivo gene therapy of Duchenne muscular dystrophy based on autologous transplantation of genetically modified myoblasts is limited by their premature senescence. MyoD-converted fibroblasts represent an alternative source of myogenic cells. In this study the forced MyoD-dependent conversion of murine NIH-3T3 fibroblasts into myoblasts under the control of an inducible promoter silent in the presence of tetracycline was evaluated. After tetracycline withdrawal this promoter drives the transcription of MyoD in the engineered fibroblasts, inducing their myogenesis and giving rise to beta-galactosidase-positive cells. MyoD-expressing fibroblasts withdrew from the cell cycle, but were unable to fuse in vitro into multinucleated myotubes. Five days following implantation of engineered fibroblasts in muscles of C57BL/10J mice we observed a sevenfold increase of beta-galactosidase-positive regenerating myofibers in animals not treated with antibiotic compared with treated animals. After 1 week the number of positive fibers decreased and several apoptotic myonuclei were detected. Three weeks following implantation of MyoD-converted fibroblasts in recipient mice, no positive "blue" fiber was observed. Our results suggest that transactivation by tetracycline of MyoD may drive an in vivo myogenic conversion of NIH-3T3 fibroblasts and that, in this experimental setting, apoptosis plays a relevant role in limiting the efficacy of engineered fibroblast transplantation. This work opens the question whether apoptotic phenomena also play a general role as limiting factors of cell-mediated gene therapy of inherited muscle disorders.

3T3 Cells↗

Muscle biopsy in Alzheimer's disease: morphological and biochemical findings.

Recent evidences of a predisposing genetic factor associated with Alzheimer's disease (DAT) suggests that important alterations may be expressed in tissues other than the brain. We present morphological and biochemical studies on muscle obtained from ten patients with Alzheimer's disease and coeval controls. Muscle biopsy examination showed an increased subsarcolemmal mitochondrial oxidative activity in three patients. The biochemical studies showed an increased oxidative enzyme activity only in the DAT group. The CoQ10 level, studied so far in three DAT patients, was greatly reduced (approximately 50%) compared with controls. Possible new peripheral markers in Alzheimer's disease will be discussed.

Aged↗

Practical value of CSF cytological examination in the diagnosis of intracranial neoplasm. A preliminary report.

The authors examined 214 CSF samples, 187 of which had been obtained by lumbar and 27 by ventricular puncture. Within 10' from time of collection, each of the CSF samples were centrifuged in a Shandow cytocentrifuge for 15' at 1500 r.p.m. Slides were made and stained according to the May-Grunwald-Giemsa method. Of the 214 samples, 137 were from patients suffering various neurological disorders while 77 were from patients affected by primitive or metastatic verified CSN neoplasms.

Brain Neoplasms↗

Neural regulation of acid maltase in an unusual adult onset deficiency.

In a 48-year-old female, the first symptoms apparently manifested themselves 18 years before, with occasional tripping and weakness in both legs. During the next 18 years, weakness progressed and the patient developed a waddling gait; she became unable to rise from a lying or seated position unassisted and the shoulder girdle also became affected. Neurological examination revealed limb and shoulder girdle predominantly involving the lower extremities. We established cell cultures from muscle biopsy specimens obtained from our patient and carried out morphological analysis which, although aspecific, demonstrated clear signs of neurogenic suffering. This was confirmed in EMG studies performed. Biochemical analysis revealed very low acid maltase residual activity. We describe an unusual case of adult-onset acid maltase deficiency (AMD) with neurogenic atrophy and low residual activity. Innervated myofibres prepared by co-culturing the patient's myoblasts, with spinal cord foetal mouse explants were not associated with an abnormal in vitro maturation of the innervated myofibres as expected by the very low residual enzymatic activity found both in the muscle biopsy specimens and in the muscle cultures. There is strong suggestion that factors other than the amount of residual activity must be involved to determine the clinical manifestation of this disease.

Animals↗

Critically ill patients: immunological evidence of inflammation in muscle biopsy.

AIM AND METHOD: To verify whether muscle necrosis in critically ill patients could be due to an inflammatory process, we tested muscle biopsies from five intensive care patients with different inflammation-specific immunocytochemical markers (antibodies anti-class I major histocompatibility complex products (class I MHCP or HLA I), membrane attack complex (MAC), T lymphocytes helper-inducer (CD4), cytotoxic (CD8) and pan-B-lymphocytes). RESULTS: In three patients muscle biopsy showed class I MHCP positivity on the surface membrane of several groups of fibres, mainly perifascicular, and scattered microvascular deposits of MAC. In the other two patients muscle biopsy did not show class I MHCP and MAC positivity. CONCLUSION: Our results suggest that inflammation may be a component of muscle damage in some critically ill patients.

Adult↗