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Biomedical subjects

M A Verity

Publications and source records attributed to M A Verity.

At least 91 records · Page 5Linked to original sources
PubMed1980

Muscle fructose 1,6-diphosphatase deficiency associated with an atypical central core disease.

A 25-year-old woman with a non-familial congenital nonprogressive myopathy was found to have atypical core-like lesions in type 1 muscle fibers. Typical core lesions (approximately 13 micrometers in diameter) and smaller, PAS positive (4.1 micrometers in diameter) atypical core were associated with a predominant type 1 fibre myopathy. A specific deficiency of fructose 1, 6-diphosphatase was found with normal values for nine other muscle glycolytic and mitochondrial marker enzymes. The data provide evidence for a specific muscle enzyme deficiency in a patient with atypical central core disease.

Adenosine Triphosphatases↗
PubMed1980

Modification of mitochondrial respiration by aging and dietary restriction.

Effects of aging and of dietary restriction on mitochondrial recovery and respiratory capacities have been assessed in mice. Old mice (23-26 months) did not differ from adult mice (9-12 months) in amounts of protein recovered in mitochondrial fractions of liver, brain and spleen, but did show a decline in specific activity of cytochrome c oxidase (cyt. c ox.) in liver and spleen. Age effects on in vitro respiration by mitochondria occurred in liver and spleen. In liver, only one substrate (beta-hydroxybutyrate) of four tested was respired at a different rate by old than by young mitochondria. Depression of state 3 respiration and 2,4-dinitrophenol (DNP)-uncoupled rates was observed for this substrate; however, this effect depended on expressing respiration on the basis of mitochondrial protein and was less overt if data were expressed per unit of cyt. c ox. activity. Old spleen mitochondria exhibited a grosser defect, showing a 40% decrease in the respiratory control index (RCI) for (succinate + rotenone)- supported respiration (the only substrate tested) due to a possible increase in state 4 rates. Effects of dietary restriction were assessed in liver and brain of 3-7-month-old mice underfed since weaning. Dietary restriction reduced recovery of total liver mitochondrial protein and liver cyt. c ox. specific activity. Liver mitochondria from restricted mice generally showed increased state 3 rates with no differences from controls in state 4 rates for respiration supported by glutamate or pyruvate + malate, resulting in an increased RCI for these substrates. DNP-uncoupled rates were also raised by dietary restriction. Unlike effects observed in old versus young mice, these differences obtained whether the data were expressed on the basis of mitochondrial protein or on cyt. c ox. activity. Electron microscopy of liver mitochondrial preparations revealed more non-mitochondrial contaminants in old mice and larger mitochondria in dietarily restricted mice. These findings are compatible with reports of age-dependent losses of liver mitochondria and suggest that dietary restriction may retard this loss.

Aging↗
PubMed1980

Polymyositis-dermatomyositis: diagnostic and prognostic significance of muscle alkaline phosphatase.

The distribution and intensity of alkaline phosphatase deposition in 54 patients with dermatomyositis-polymyositis (PM-DM) was analyzed by the enzyme histochemical method. Increased enzyme reactivity of endomysial capillaries was found in 28% of patients, equally distributed between adult onset PM (Group I) and PM-DM with overlap in other connective tissue diseases (Group V). Patients with high endomysial capillary reactivity (R1 larger than or equal to 60) responded poorly to steroids, had an increased incidence of rheumatoid factor, and had less fiber degeneration/necrosis in their biopsies. Twenty-two percent of patients demonstrated prominent perimysial phosphatase reactivity localized in newly formed collagen and fibroblasts. Thirty patients (55%) demonstrated significant numbers of alkaline-phosphatase-positive fibers positively correlated with increased fiber degeneration/necrosis, endomysial fibrosis, increased numbers of triglyceride-containing muscle fibers, and NADH tetrazolium reductase hyperreactivity. Minimal overlap between the three enzyme distribution patterns was found. Endomysial capillary activity probably represents endothelial alkaline phosphatase induction analogous to the pattern seen normally in lower mammals (rat, rabbit, guinea pig). Alkaline phosphatase fiber reactivity probably represents a particular phase in fiber regeneration/maturation especially after denervation and is positively correlated with an increased incidence of spontaneous fibrillation potentials in PM-DM.

Adult↗
PubMed1978

Scleromyxedema myopathy. Histochemical and electron microscopic observations.

A biopsy-proven case of scleromyxedema (papular mucinosis) with IgG lambda light chain paraproteinemia, eosinophilia and severe proximal myopathy is presented. Muscle biopsy revealed an atypical necrotizing vacuolar myopathy. Histochemical studies of cryostat sections revealed fiber necrosis, severe type II fiber atrophy, and fiber vacuolization with NADH tetrazolium reductase hyperactivity. Electron microscopy showed myocytolysis, reduplication of the basement membrane, and unit membrane-lined vacuoles negative for acid mucopolysaccharide.

Biopsy↗
PubMed1978

Familial neuromuscular disease with type 1 fiber hypoplasia, tubular aggregates, cardiomyopathy, and myasthenic features.

Three sisters had autosomal recessive inheritance of a cardiomyopathy, and nonprogressive proximal muscle weakness and lordosis that began in childhood. Small type 1 fibers and tubular aggregates in both fiber types were found on muscle biopsy. In addition, myasthenic features were characterized by fatigability with moderate exercise, decremental response to repetitive nerve stimulation, and improved function with anticholinesterase drug therapy.

Cardiomyopathies↗
PubMed1977

Papular mucinosis with myopathy, arthritis, and eosinophilia. A histopathologic study.

A patient with biopsy-proven papular mucinosis, plus the characteristic IgG lambda light chain paraproteinemia, also developed a severe proximal myopathy, seronegative inflammatory polyarthritis, and marked eosinophilia. Muscle enzymes were elevated, EMG was compatible with polymositis, and muscle biopsy revealed an atypical necrotizing vacuolar myopathy. Synovial biopsy revealed an inflammatory synovitis with Class II synovial fluid. No mucin deposition was detectable in muscle or synovium. During 7 years of observation, corticosteroids and various immunosuppressive agents were successively administered with little benefit. Recently, weekly intravenous methotrexate and low-dose oral corticosteroids have resulted in clinical and laboratory improvement. It is suggested that the pathology in papular mucinosis may include serious rheumatic manifestations in addition to the cutaneous involvement.

Arthritis↗
PubMed1977

Infantile Gaucher's disease: neuropathology, acid hydrolase activities and negative staining observations.

A case of infantile Gaucher's disease with widespread cerebral degenerative changes is presented. Neuropathological features included perivascular Gaucher cell infiltrates accompanied by periadventitial fibrogliosis, focal neuronophagia, Purkinje cell vacuolation and diffuse astrocytosis of cerebellar white matter, brain stem and spinal paracentral grey matter. Gaucher cell tubules were isolated from formalin fixed material. Negative staining confirmed the appearance of a coiled helical structure, 200--400 A in diameter composed of microfibrils. A relative deficiency of acid beta-glucosidase was found in spleen homogenate accompanied by a considerable increase in acid phosphohydrolase, N-acetylglucosaminidase, beta-glucuronidase and beta-galactosidase.

Brain↗
PubMed1977

Atypical fibrous histiocytoma of the orbit: an electron-microscopic study.

A young woman developed progressive proptosis of her right eye, accompanied by retinal striae, exposure keratopathy and a severe decrease in visual acuity, reflecting optic neuropathy. An atypical fibrous histiocytoma was found within the orbit. She received orbital exenteration and irradiation. 2 years later she is free of clinical recurrence.

Adult↗
PubMed1976

Cerebral lymphomatoid granulomatosis. A report of two cases, with disseminated necrotizing leukoencephalopathy in one.

Neuropathologic findings in 2 cases of cerebral lymphomatoid granulomatosis with sequelae are presented. A 30-year old male with macular rash and pulmonary lymphomatoid granulomatosis responded to Prednisone terapy but developed acute intracranial hypertension with coma. A necrotizing hemorrhagic lesion was evident in the left putamen surrounded by diffuse and perivascular atypical lymphoplasmacytic infiltration. An 18-year old girl developed pulmonary lymphomatoid granulomatosis, diplopia, slurred speech and right hemiparesis. Brain scan, angiography and EEG suggested a left fronto-parietal mass assumed to represent lymphomatoid granulomatosis. She responded well to cerebral irradiation, intrathecal methotrexate and cytoxan but relapsed with seizures and increasing respiratory insufficiency. At autopsy, stigmata of cerebral lymphomatoid granulomatosis were absent but a parenchymatous degeneration consistent with disseminated necrotizing leukoencephalopathy following antileukemic therapy in children, was found.

Adolescent↗
PubMed1976

Effects of neonatal hypothyroidism on cerebral and cerebellar synaptosome development.

The effect of hypothyroidism on cerebral and cerebellar synaptosome development has been studied. Neonatal hypothyroidism was induced following addition of 0.3% propylthiouracil to the diet of nursing mothers. Maturation profiles of total synaptosome fraction and specific activities of lactate dehydrogenase, Na+K ATPase, cytochrome c oxidase, and protein were obtained from days 6 to 32 on synaptosomes isolated from Ficoll-sucrose gradients. The greatest changes were found in the total activities of enzymes isolated from the cerebellum. Hypothyroidism induced a retardation of LDH and cytochrome c oxidase in cerebellar synaptosomes, but no change in corresponding specific activities. Maximum rates of 14C-leucine incorporation into cerebellar synaptosome protein was found at 16-20 days, after which a rapid decline occurred to adult levels at 32 days. In neonatal hypothyroidism, synthesis was significantly reduced at 8 and 14 days, but reached control levels or above at 21--32 days. In the cerebrum, maximum rates of 14C-leucine incorporation into synaptosome protein were identified at 8--12 days in normal with a rapid drop to adult levels at approximately 20 days. In neonatal hypothyroidism, peak activities were identified at 14 days and increased activities over control were noted at 14, 20 and 30 days. These observations demonstrate the sensitivity of the developing cerebellar synaptic apparatus to neonatal hypothyroidism, with a protraction in the peak levels of synaptosome protein synthesis in cerebrum and cerebellum.

Adenosine Triphosphatases↗
PubMed1976

Familial progressive bulbar and spinal muscular atrophy. Juvenile onset and late morbidity with ragged-red fibers.

Six members of a family had a neurologic disease with autosomal dominant transmission and adolescent onset of progressive wasting of predominantly distal axial muscles and muscles innervated by cranial nerves V, VII, X, and XII, leading to severe morbidity in adulthood. Muscle biopsy of the propositus revealed "ragged-red" fibers, while electromyography and autopsy material were consisted with a neurogenic disease. The case seemed unique to any clinicogenetic nosology, because it was associated with a cardiac conduction defect, a mitochondrial abnormality in skeletal muscle, and a course, distribution, and degree of weakness that included features of both chronic spinal muscular atrophy and amyotrophic lateral sclerosis.

Adult↗