PubMed Health⌕ Search

Biomedical subjects

G Scarlato

Publications and source records attributed to G Scarlato.

17 recordsLinked to original sources
PubMed1979

Progressive extrinsic ophthalmoplegia with peripheral neuropathy and storage of muscle glycogen.

A case of progressive extrinsic ophthalmoplegia associated with peripheral neuropathy and hypertriglyceridemia type IV is described. Motor and sensory conduction velocities of the spinal nerves were severely decreased, while the EMG of the facial muscles was more suggested of a myopathic disorder. Electron microscopic study of biopsies of biceps and peroneus brevis muscles disclosed many ragged red fibers, mainly type I, which contained typical abnormal mitochondria. Other fibers, all type II, contained increased amounts of glycogen between myofibrils or beneath the sarcolemmal membrane, but the mitochondria were normal. These fibers were more abundant in the peroneus brevis than in the biceps muscle. Nerve biopsy revealed marked loss of myelinated fibers, but neither mitochondrial changes nor glycogen storages were evident in Schwann's cells. Biochemical investigations confirmed the increased amount of glycogen in both muscle biopsies and revealed a decrease of guanilcyclase. Phosphorylase, phosphorylase b kinase, adenilcyclase, and carnitine concentrations were all normal. The pathogenesis of this syndrome is discussed and the relationship between mitochondrial abnormalities and glycogen accumulation in muscle tissue are considered.

Adult↗
PubMed1979

Hemiparkinsonism. A human model for studying dopaminergic supersensitivity.

The observation of a patient suffering from a parkinsonian syndrome, almost entirely expressed on the right side, and "on-off" attacks with rotatory movement of the trunk, led us to consider that the rotational model of animals may be reproduced in man. The symptoms presented by our patient may reflect a predominant degeneration in the nigrostriatal pathway of the left side. We suggest that his torsion behavior is due to hypersensitivity phenomenon of the dopaminergic receptors on this side.

Animals↗
PubMed1979

Erythrocyte spectrofluorometric abnormalities in Duchenne patients and carriers. A new approach to carrier detection.

Duchenne muscular dystrophy (DMD) is a disorder whose pathogenesis is attributed, according to the most recent theories, to generalized membrane abnormalities, including red cell membrane. The study of erythrocyte ghosts in patients affected by DMD showed alterations in ion transport and in various enzymatic activities. Employing a spectrofluorometric method using 1-anilino-8-naphthalene sufonate (1.8-ANS) we have tried to characterize the erythrocyte ghosts of DMD patients, definite DMD carriers and normal controls, matched for age and sex. We found an increase of membrane polarity in DMD and definite DMD-carrier erythrocyte ghosts. Using this new method we were able to: - confirm by means of a different technique the previous observations of many authors on erythrocyte ghost alterations in DMD - find a new technique useful in detecting the DMD carriers. It is noteworthy that in such a way the detection rate of definite DMD carriers was higher than with the CPK test.

Adult↗
PubMed1978

Muscular carnitine synthesis and palmitate metabolism in vitro.

The carnitine content of the culture media for normal and pathological human muscles, including a case of systemic carnitine deficiency (SCD) was measured and the carnitine concentration was the same in all normal and pathological muscle culture media. Carnitine was never detected in growth medium. Some fibroblasts and myoblasts were filled with neutral lipids in SCD. 14C-palmitate added to the medium was incorporated by SCD fibroblasts or myoblasts to the same concentration as in normal or pathological cells. Factors other than carnitine seem to account for the lipid accumulation of SCD in cell culture.

Carnitine↗
PubMed1978

The syndrome of carnitine deficiency: morphological and metabolic correlations in two cases.

Two cases of systemic carnitine deficiency are described. In both patients, carnitine concentration was lower than normal in serum and muscle tissue. In the first case, the illness began at age 35; the clinical manifestations were only muscular. In the second case, the illness began in childhood; there were intermittent episodes of hepatic enlargement and coma. An excessive lipid content was present in muscle tissue, especially in type 1 fibers, of both cases, and in the liver of the second patient. Ultrastructural studies of muscle tissue revealed important changes of mitochondria. During muscular exercise, aerobic and anaerobic metabolism were investigated. For a given relative work intensity, these patients showed abnormally high blood lactic acid concentration and lactic acid/pyruvic acid ratios. These data, together with the morphological alterations observed in mitochondria, suggest an impaired function of the respiratory chain, leading to a shift of the red/ox potential of the tissue towards a non reduced state.

Adult↗
PubMed1978

Morphologic and metabolic studies in a case of oculo-cranio-somatic neuromuscular disease.

A case resembling the syndrome of "ophthalmoplegia plus" or "oculo-cranio-somatic neuromuscular disease" is reported. A biopsy of deltoid muscle showed that 23% of the fibers were "ragged-red fibers" and were all type 1. Study of their ultrastructure revealed clusters of abnormal skeletal muscle mitochondria in subsarcolemmal and intermyofibrillar spaces. A liver biopsy also revealed a considerable increase in the number and size of the mitochondria. In some instances the mitochondria contained osmiophilic rounded inclusions surrounded by myelin-like structures. Metabolic studies revealed an increase of blood lactate concentration after very light exercise, while the O2 consumption was increased within the expected range. It is concluded that: a) the association of ophthalmoplegia and ultrastructural alterations of the mitochondria in muscle fibers may represent a specific nosographic entity: b) mitochondrial abnormalities are not limited to the skeletal muscles and c) the dysmetabolic basis of such a clinico-pathological entity might lie in an alteration of the mechanism which regulates the mitochondrial oxidative phosphorylation.

Adult↗
PubMed1977

Quantitative EMG and histological carrier detection of Duchenne muscular dystrophy.

Seventy-nine women known as, or suspected to be, carriers of the Duchenne type of muscular dystrophy were examined. The 15 known carriers had an estimation of the CPK serum level and a manual quantitative EMG, which gave the high detection rate of 93%. The 64 suspected carriers had CPK determination and quantitative EMG, or CPK and muscle biopsy, and the value of each technic is discussed. The problem of giving a reassuring answer to women considered to be possible carriers on genetic criteria, but who are not really carriers, is solved if the results of all three tests are negative.

Action Potentials↗
PubMed1977

A case of lipid storage myopathy with carnitine deficiency. Biochemical and electromyographic correlations.

Histochemical, biochemical and electromyographic studies were performed in a case of carnitine deficiency in serum and in muscle. Clinical features include proximal muscle weakness, predominant type I fiber impairment, excess of triglycerides and moderate glycogen accumulation in muscle. No abnormalities of palmityl CoA synthetase, carnitine palmityl transferase, carnitine acetyl transferase and lipase were evidenced. An interesting EMG decremental pattern was recorded. Correlations between electromyographic and biochemical findings are considered. A clinical improvement, a normal plasma carnitine level and a normal response at EMG repetitive stimulation were found after carnitine treatment.

Adult↗
PubMed1976

Quantitative electromyography in the detection of the carriers in Duchenne type muscular dystrophy.

The quantitative EMG technique was used to detect Duchenne muscular dystrophy carriers. The tests were carried out, measuring the parameters of M.U. potentials (the duration, the phase, and the 0 index according to Van den Bosch, modified by Gardner-Medwin), and using the Willison analyzer, in a group of carriers and normal subjects. Ten M.U. potentials from the deltoid, biceps brachii and quadriceps muscles were photographed and measured in each subject, and the right and the left biceps were examined with the Willison analyzer. An high detection rate was obtained by manual EMG, measuring traditional values such as mean number of phases, A.P. duration and 0 index. The Willison analyzer was significant in 2 known carriers. The total EMG detection rate was higher than the CPK tests both in the known carriers and the possible carriers. It is concluded that the quantitative EMG technique is an useful and specific test to detect carriers of the gene of Duchenne muscular dystrophy.

Action Potentials↗
PubMedDate not supplied

Myosin polymorphism in human skeletal muscles.

Myosins isolated from individual human muscles (primarily normal muscles) were investigated with respect to their structural and catalytic properties. The results indicate unexpected elements of uniformity shared by the several myosins, such as a three-banded, electrophoretic pattern of light chains in sodium dodecylsulfate (SDS) gels and a low degree of alkaline lability. The pH activity profile and the effect of KCl on myosin ATPase activities were also found to be the same for the myosins from predominantly fast (e.g., vastus lateralis and rectus abdominis) and slow (e.g,, soleus and pectoralis minor) muscles. Coelectrophoretic experiments lend further credence to the interrelationship between human myosin light chains and the light chains of rabbit fast-muscle myosin. However, several kinds of circumstantial evidence, such as that derived from the study of myosin in nemaline myopathy, suggest that one shoould exercise caution in interpreting these results. On the other hand, human muscle myosins, like those of other mammalian species, can be divided into two main categories according to the peptide composition of tryptic heavy meromyosin (HMM) and the banding pattern of light meromyosin (LMM) paracrystals. These results, which are indicative of differences in the primary structure of the heavy chains, allow us to identify these heavy chains as the main site of heterogeneity among myosins in human mucles.

Adenosine Triphosphatases↗
PubMedDate not supplied

Treatment of denervated muscle by gangliosides.

Short-duration cooling of the nerve to the extensor digitorum longus muscle of the rat in vivo induced partially reversible denervation of the muscle and atrophy in the type 2 muscle fibers. Increases in cyclic adenosine monophosphate, cyclic guanosine monophosphate phosphodiesterase, adenylate cyclase, and guanylate cyclase were observed in the denervated muscle. Treatment with gangliosides of the bovine brain cortex seemed to improve the excitability of the surviving motor units and to encourage recovery of neuromuscular trophic control, but it did not affect the nerve conduction velocity or the contractile properties of the denervated muscle.

Animals↗
PubMedDate not supplied

[Prevention of duchenne's muscular dystrophy: methodological problems in the detection of carriers (author's transl)].

In the last five years 48 possible carries and 13 known carriers of the gene for the Duchenne type of muscular dystrophy were studied in the Neurological Institute of the University of Milan. To achieve the most accurate detection, the following tests are recommended: a) the serum creatine kinase (CPK) estimation; b) quantitative EMB test on 3 muscles (deltoid, biceps and vastus medialis), in case of normal CPK level; c) histological and histochemical studies, only if tests a) and b) are uniformative.

Adolescent↗