Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1762617 (weakness)
 37,932 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three bedouin children with mitochondrial myopathy due to cytochrome c oxidase deficiency presented with progressive muscle weakness, failure to thrive, proximal renal tubular acidosis, and lactic acidemia leading to death. Two died by age 5 months and one by age 16 months. Cytochrome c oxidase was markedly reduced in skeletal muscle extracts of all three. Three other children of the same family with most probably the same metabolic aberration are also described. We suggest an autosomal recessive inheritance for this lethal mitochondrial myopathy.
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PMID:Autosomal recessive lethal infantile cytochrome C oxidase deficiency. 185 96

A case of mitochondrial myopathy with mononeuritis multiplex was described. A 55-year-old man was hospitalized because of blepharoptosis and muscle weakness. His mother also showed blepharoptosis in her elderly stage of life. He had been healthy until 46 years of age, when he first noticed difficulty of speech, followed by bilateral blepharoptosis, weakness of upper limbs, and sensory disturbance in the left occipital, and left upper and lower extremities. These symptoms progressed slowly. On admission, bilateral blepharoptosis was recognized. Slightly to moderate muscle wasting and weakness were observed in the face, neck, trunk, and extremities. Areflexia was observed in the upper extremities. Paresthesia was observed in the left occipital and left hip, and superficial sensation was impaired in the left upper and lower extremities. Electromyographic examination of extremities showed neurogenic changes in the distal muscles and myogenic changes in the proximal muscles. Motor conduction velocities were normal, but sensory conduction velocities decreased in amplitude on the left upper extremity and were not evoked on the left lower extremity. Muscle biopsy specimen revealed numerous "ragged-red" fibers. Cytochrome c oxidase stain showed a decrease in intensity of staining. A sural nerve biopsy showed slight axonal degeneration and slight loss of nerve fibers. Biochemical analysis on biopsy muscle showed partial deficiency of cytochrome c oxidase activity.
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PMID:[A case of mitochondrial myopathy with mononeuritis multiplex]. 224 28

We reported a 3-week-old girl with profound generalized weakness, requiring assisted ventilation. There was no consanguinity or family history of any neuromuscular disorders. Serum levels of GOT, GPT and CK were slightly elevated. Although the clinical manifestations mimicked those of Werdning-Hoffmann disease, a lack of the respiratory muscle involvement and the presence of high serum lactate levels suggested an underlying metabolic disorder. During the observation over the months, she gradually improved clinically and assisted ventilation was discontinued at 19 months. Muscle biopsies were performed at 4 and 19 months of age. The first biopsy showed an excessive mitochondrial aggregation and numerous ragged-red fibers. The second biopsy revealed rare ragged-red fibers. However there were definite neurogenic changes including type grouping and angulated fibers. Cytochrome c oxidase (CCO) stain was positive in less than 5% of fibers in the first biopsy but in all fibers in the second biopsy. Biochemical analysis using muscle specimens showed a decreased CCO activity; 18.5% of the control level in the first biopsy and 53.3% in the second biopsy. Immunocytochemistry showed the presence of immunologically reactive enzyme protein in both biopsies. Clinical manifestations of our patient were almost identical to those of two cases reported by DiMauro, et al (1983). The enzyme defect in this case was reversible in contrast to that in the fatal infantile form of CCO deficiency. Histochemical and biochemical bases for these differences were discussed.
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PMID:[Benign infantile mitochondrial myopathy due to reversible cytochrome c oxidase deficiency: histological and biochemical analysis]. 255 79

A 2-month-old boy had progressive generalized weakness, hypotonia, and respiratory insufficiency requiring assisted ventilation. At age 3 1/2 months, he started having seizures and recurrent pulmonary infections; he died at age 7 months. Serum lactate was chronically elevated, but there was no aminoaciduria. Histochemical and ultrastructural studies of muscle biopsies at ages 2 and 3 months showed excessive mitochondria, lipid, and glycogen; a third biopsy at 6 months showed marked increase in perimysial fibrous and fat tissue. Cytochrome c oxidase activity was 7% of normal in the first biopsy and undetectable in the others. Cytochrome spectra of mitochondria isolated from postmortem muscle showed complete lack of cytochrome aa3. Antibodies were obtained against cytochrome c oxidase purified from normal human heart. Immunotitration and enzyme-linked immunosorbent assay (ELISA) showed decreased immunologically reactive enzyme protein in the patient's muscle, but SDS-PAGE electrophoresis of immunoprecipitates of muscle mitochondrial extracts showed the presence of all cytochrome c oxidase subunits. These data suggest that decreased synthesis of one or more subunits may result in markedly decreased concentration of electrophoretically normal complex IV in skeletal muscle.
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PMID:Fatal infantile cytochrome c oxidase deficiency: decrease of immunologically detectable enzyme in muscle. 298 57

The son of third cousins was normal until age 2 when he had difficulty walking. At age 8 there was limb weakness, ataxia, loss of tendon reflexes, dislalia, and he was mildly retarded. During fasting, urinary organic acid excretion was abnormally high. Cytochrome c oxidase activity in muscle was 7% of the normal mean. The enzyme in platelets was 16% of controls with a decreased cytochrome aa3 peak. These data suggest an autosomal recessive transmission of this variant of cytochrome c oxidase deficiency.
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PMID:Childhood encephalomyopathy with cytochrome c oxidase deficiency, ataxia, muscle wasting, and mental impairment. 301 3

A 3-day-old girl had a syndrome of lethargy and lactic acidosis. Pregnancy and delivery had been normal; there was no consanguinity or family history of neuromuscular disease. At age 4 1/2 months, she had generalized weakness, hypotonia, areflexia, and macroglossia. She developed cyanosis and respiratory failure, and marked cardiomegaly was noted. She died at age 8 1/2 months of cardiac arrest. Results from a muscle biopsy specimen obtained at age 4 1/2 months showed ragged-red fibers and increased glycogen and lipid droplets. With the cytochrome c oxidase reaction, only 5% of the fibers stained positively in the biopsy specimen. Cytochrome c oxidase activity was 7.3% of normal in muscle mitochondria and 12.2% of normal in heart mitochondria. Reduced-minus-oxidized cytochrome spectra showed lack of the cytochrome aa3 peak. Immunotitration using antibodies against purified human heart cytochrome c oxidase showed normal amount of cross-reacting material in both heart and muscle. The genetic error could have involved a cytochrome c oxidase isozyme common to heart and muscle.
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PMID:Myopathy and fatal cardiopathy due to cytochrome c oxidase deficiency. 302 95

A 2-week-old boy had profound generalized weakness, hypotonia, hyporeflexia, macroglossia, and severe lactic acidosis. The infant improved spontaneously: he held his head at 4 1/2 months, rolled over at 7 months, and walked by 16 months. At 33 months of age, he had mild proximal weakness. Macroglossia disappeared by age 4 months. Blood lactic acid declined steadily and was normal by 14 months of age. Histochemical and ultrastructural studies of muscle biopsy specimens obtained at 1 and 7 months of age showed excessive mitochondria, lipid, and glycogen; a third biopsy at age 36 months showed only atrophy of scattered fibers. Cytochrome c oxidase stain was positive in fewer than 5% of fibers in the first biopsy, in approximately 60% of fibers in the second biopsy, and in all fibers in the third biopsy. Biochemical analysis showed an isolated defect of cytochrome c oxidase activity, which was only 8% of the lowest control level in the first biopsy; the activity increased to 47% in the second biopsy and was higher than normal in the third. In contrast to that in the fatal infantile form of cytochrome c oxidase deficiency, the enzyme defect in this condition is reversible. The biochemical basis for this difference remains to be explained.
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PMID:Benign infantile mitochondrial myopathy due to reversible cytochrome c oxidase deficiency. 631 69

A case of cytochrome c oxidase deficiency primarily affecting skeletal muscle is described. The child was admitted at 4 weeks due to failure to thrive and examination at that time revealed weakness and hypotonia. His condition deteriorated until at 11 weeks respiratory arrest necessitated artificial ventilation and death occurred at 14 weeks. Biochemical investigation showed lactic acidaemia and generalised aminoaciduria. Histochemical examination of muscle obtained at biopsy showed strong reactions for some oxidative enzymes, but by contrast cytochrome c oxidase could not be detected. Cytochrome c oxidase activity was less than 5% of control values in an extract of fresh muscle. The reduced-minus oxidised absorption spectra of muscle mitochondrial fractions prepared from post-mortem tissue showed an absence of cytochrome aa3 and a partial deficiency of cytochrome b. Ultra-structural examination showed abnormal mitochondria with loss of cristae and an abnormal granular matrix. The family history suggests autosomal recessive inheritance.
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PMID:Fatal infantile mitochondrial myopathy due to cytochrome c oxidase deficiency. 631 67

We report a family of mitochondrial myopathy which appeared to be interited as an autosomal dominant trait. The proband is a 58-year-old Japanese male, who presented with bilateral ptosis, chronic progressive ophthalmopletia, dysphagia, and atrophy of proximal muscles in the upper extremities. There was no cataract or retinal degeneration. Serum creatine kinase (CK) and lactic acid levels were normal. Cardiac evaluations were normal. Muscle biopsy revealed 7% of ragged red fibers. Cytochrome c oxidase activity in the muscle was decreased to 50% of the control value. PCR analysis of muscle mitochondrial DNA revealed 3 large-scale deletions in the non-D-loop regions, ranging in size from 4.2 kb to 5.2 kb. His father, three siblings, and the two children had symptoms similar to the proband. We have reviewed forty-five individuals from six families, including our family, who had mitochondrial myopathy with autosomal dominant inheritance. Frequent manifestations include chronic progressive ophtalmoplegia (91.2%), ptosis (95.6%), hearing loss (72.7%), dysphagia (60.0%), limb weakness (74.1%), and respiratory muscle weakness (75.0%). Interestingly, there is no individual with retinal degeneration or cardiac involvement. Serum CK and lactic acid levels may be elevated. CT of the head is normal. Muscle biopsy shows ragged red fibers and the frequency of cytochrome c oxidase-negative fibers ranges from 0 to 38%. Multiple large-scale deletions of mitochondrial DNA, ranging in size from 4.2 to 8.3 kb, are found in the muscle, all of which are located in the non-D-loop region of the mitochondrial DNA. The multiplicity of deletions may be one to the characteristic features of this form of mitochondrial myopathy.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Mitochondrial myopathy with autosomal dominant inheritance--report of a family and review of the literature]. 831 87

There are few descriptions about the clinical course of children with myoclonus epilepsy with ragged-red fibers (MERRF). We reported a girl who was diagnosed as having MERRF at 10 years of age and developed various clinical manifestations including chronic respiratory failure, paralytic ileus and pancytopenia at 18 years of age. Administration of cytochrome c worsened lactic acidosis and muscle weakness, while intravenous hyperalimentation with copper supplementation gradually improved these findings as well as pancytopenia. Cytochrome c oxidase is a copper dependent enzyme. Its activity is extremely low in MERRF patients. It was suspected that deficiency of serum copper and supplementation of cytochrome c worsened the clinical symptoms of our patient.
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PMID:[A case of childhood onset myoclonus epilepsy with ragged-red fibers--with special reference to various clinical manifestations]. 1223 56


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