Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026827 (hypotonia)
 5,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cerebrospinal fluid aminoacid analysis in a girl with severe psychomotor retardation, hypotonia, hyperreflexia and growth acceleration showed highly increased levels of free gamma-aminobutyric acid (4.8 mumol/l; range in twenty controls 0.04-0.12, median 0.08), homocarnosine, a dipeptide of gamma-aminobutyric acid and histidine (23.4 mumol/l; control range 4.0-8.7, median 7.6) and of beta-alanine, an alternative substrate for gamma-aminobutyric acid-transaminase (0.48 mumol/l; control range 0.02-0.06, median 0.05). Liver gamma-aminobutyric acid-transaminase activity was deficient (0.07 mumol/mg protein h; range in ten controls 0.31-0.69, median 0.38). Fasting plasma growth hormone levels were increased (7.9-38.4 ng/ml; nl less than 5). Brain evoked responses were suggestive of leukodystrophy. A brother of this patient, showing a similar clinical picture, had died at one year. Postmortem examination of his brain showed leukodystrophy of the type seen in amino acidopathies such as phenylketonuria. This appears to be the first report of gamma-aminobutyric acid-transaminase deficiency.
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PMID:Gamma-aminobutyric acid-transaminase deficiency: a newly recognized inborn error of neurotransmitter metabolism. 614 8

A two year and ten-month-old girl with cerebello-brain stem leukodystrophy is presented. She was hypotonic with spasticity and showed delayed motor development until she was twelve months old, when regression of motor activities began. Progressive hypotonia, dysphagia and fatal respiratory abnormalities developed. Auditory brain stem response was absent. Pathological examination revealed primary demyelination with a predilection for the cerebellum, brain stem and spinal cord, in association with changes of the cerebellar cortex, pontine nuclei, inferior olivary nuclei and part of the basal ganglia. Clinical, pathological and biochemical studies revealed that this disease is different from metachromatic leukodystrophy, Krabbe's globoid cell leukodystrophy and adrenoleukodystrophy. The clinical entity of cerebello-brain stem orthochromatic leukodystrophy is discussed.
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PMID:Cerebello-brain stem orthochromatic leukodystrophy with floppiness and bulbar paralysis. 647 80

The clinical distinction between patients with a disorder of peroxisome assembly (e.g., Zellweger syndrome) and those with a defect in a peroxisomal fatty acid beta-oxidation enzyme can be difficult. We studied 29 patients suspected of belonging to the latter group. Using complementation analysis, 24 were found to be deficient in enoylcoenzyme A hydratase/3-hydroxyacylcoenzyme A dehydrogenase bifunctional enzyme and 5 were deficient in acyl-CoA oxidase. Elevated plasma very long-chain fatty acids (VLCFA), impaired fibroblast VLCFA beta-oxidation, decreased fibroblast phytanic acid oxidation, normal plasmalogen synthesis, normal plasma L-pipecolic acid level, and normal subcellular catalase distribution were characteristic findings in both disorders. The elevation in plasma VLCFA levels and impairment in fibroblast VLCFA beta-oxidation were more severe in bifunctional-deficient than in oxidase-deficient patients. The clinical course in bifunctional deficiency (profound hypotonia, neonatal seizures, dysmorphic features, age at death approximately 9 months) was more severe than in oxidase deficiency (moderate hypotonia without dysmorphic features, development of a leukodystrophy, age at death approximately 4 yr). Based on these findings, accurate early diagnosis of these deficiencies of peroxisomal beta-oxidation enzymes is possible.
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PMID:Distinction between peroxisomal bifunctional enzyme and acyl-CoA oxidase deficiencies. 766 38

Two brothers with profound neonatal hypotonia and hyporeflexia and electrodiagnostic testing consistent with lower motor neuron pathology were found to have a leukodystrophy. Using single-strand conformational polymorphism analysis and direct sequencing, a mutation within exon 3 of the gene encoding proteolipid protein (Gly73Arg substitution) was previously detected in both brothers and their mother, establishing the diagnosis of Pelizaeus-Merzbacher disease. Despite reported sparing of the peripheral nervous system in Pelizaeus-Merzbacher disease, we suggest that proteolipid protein gene products may influence the development of anterior horn cells or peripheral nervous system myelin and that some individuals affected with this disease may present with clinical and electromyographic features suggestive of neonatal spinal muscular atrophy.
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PMID:Pelizaeus-Merzbacher disease presenting as spinal muscular atrophy: clinical and molecular studies. 799 80

We report on a patient affected by congenital muscular dystrophy, severe psychomotor retardation, severe hypotonia, papillar hypoplasia and peculiar NMR pattern of hydrocephalus, Dandy-Walker malformation and leukodystrophy. These findings are intermediate between Walker-Walburg syndrome, Fukuyama disease and Occidental congenital muscular dystrophy. Our case focuses on the wide spectrum of congenital muscle dystrophy associated with central nervous system disease and on the difficulties of genetic counseling in these families.
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PMID:Report on a patient with congenital muscular dystrophy, hydrocephalus, Dandy-Walker malformation and leukodystrophy. 811 Apr 18

Pelizaeus-Merzbacher disease (PMD) is a degenerative leukodystrophy of the central nervous system resulting in progressive spasticity and neurologic deterioration. Seitelberger (13) divided this rare disease into six types. Five patients with the type 1 and two patients with the type II form of PMD have been treated at the Children's Hospital of Eastern Ontario. Our study sought to identify the orthopaedic manifestations of PMD and to develop a common orthopaedic profile for these patients. All children with types I and II PMD developed spastic quadriparesis, truncal hypotonia, thoracolumbar scoliosis, soft-tissue contractures of the adductors and hamstrings, osteopenia, bilateral coxa valga, and associated hip dislocation.
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PMID:The orthopaedic manifestations of Pelizaeus-Merzbacher disease in children. 890 38

The classical form of congenital muscular dystrophy (CMD) is now classified into merosin-deficient and -positive forms. The merosin (laminin alpha 2) is one of three subunits of a muscle basement membrane protein, laminin. Patients with the merosin-deficient form have generalized muscle weakness and hypotonia from early infancy as seen in FCMD but with no significant central nervous system involvement. The serum creatine kinase (CK) is markedly elevated. Strikingly all patients examined by a CT/ MRI have diffuse white matter abnormalities mimicking leukodystrophy. The gene has been mapped to chromosome 6q2 in the coding region for merosin. Since the responsible gene and protein have not been identified in the merosin-positive form, this CMD is probably a group of heterogeneous diseases. The overall symptoms are mild, approximately 90% of patients learned to walk alone.
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PMID:[Non-Fukuyama type congenital muscular dystrophy--merosin deficient and positive forms]. 943 31

The congenital muscular dystrophies are a heterogeneous, recessively inherited group of disorders that have been subclassified on the basis of clinical central nervous system involvement. We report two children with "pure" congenital muscular dystrophy, one merosin negative and one merosin positive with extensive white matter and occipital cortical neuromigration abnormalities on magnetic resonance imaging (MRI). The first patient (merosin-negative congenital muscular dystrophy) presented with hypotonia and weakness in the neonatal period and subsequently was found to have a leukoencephalopathy and occipital cortical dysplasia on magnetic resonance imaging. The second patient presented with developmental delay without definite weakness. Initial investigations revealed a leukoencephalopathy and cortical dysplasia, but the patient subsequently was shown to have merosin-positive congenital muscular dystrophy. These patients illustrate that white-matter changes are not specific for merosin-negative congenital muscular dystrophy alone and that extensive cortical abnormality can be found in both groups of patients. In addition, our second patient illustrates a nonmuscular mode of congenital muscular dystrophy presentation that should be considered in patients with a "nonprogressive leukodystrophy."
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PMID:Congenital muscular dystrophy, white-matter abnormalities, and neuronal migration disorders: the expanding concept. 979 53

The rapidly expanding use of magnetic resonance imaging (MRI) in children with neurological impairments of unknown aetiology has revealed a large number of children with abnormalities of the cerebral white matter, some with leukodystrophy-like white matter abnormalities on MRI, but non-progressive in clinical presentation and course. The aim of this study was to investigate the clinical and neuroradiological characteristics of 26 children with white matter abnormalities of unknown origin and to find diagnostic clues or indicators of progressive versus nonprogressive disease. The typical child with white matter abnormalities was characterized by onset of symptoms within the first year of life, most often presenting as general developmental delay and hypotonia. Later-appearing signs were spasticity and ataxia and as a rule severe learning and motor disabilities. Serious ophthalmological signs were frequently seen. Perinatal adverse events were rare, infectious aetiologies not indicated but prenatal stigmata relatively common. The clinical course was progressive in 11 children and non-progressive in 15. Late onset presentation was associated with a progressive course whereas prenatal stigmata and asymmetrical white matter lesions only were found in children with a non-progressive disorder. The MRI showed three main patterns: a) a generalized increase of the T2 signal of the white matter in 12 children, b) a bilateral, symmetric but not generalized abnormality in nine and c) asymmetric, focal or multifocal pathology in five. Useful information as to clinical entities and course was obtained from the combined clinical and radiological assessment. A precise nosological diagnosis could be made in six cases. The study showed that white matter abnormalities in children constitute a heterogeneous group of rare and 'anonymous' conditions, motivating collaborative studies for further clarification of background and management.
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PMID:Clinical characteristics of children with cerebral white matter abnormalities. 1070 Nov

Canavan disease is a severe progressive leukodystrophy characterized by swelling and spongy degeneration of the white matter of the brain. It is an autosomal recessive disease found more frequently among Ashkenazi Jews. The clinical features are those of severe mental retardation with inability to gain developmental milestones. Hypotonia, head lag and macrocephaly are characteristic of Canavan disease and become apparent after 5-6 months of age. Massive excretion in the urine of N-acetylaspartic acid is the biochemical marker for Canavan disease, which is caused by deficiency of the enzyme aspartoacylase. This discovery allowed for accurate diagnosis of Canavan disease, while prior to that, a brain biopsy was needed. The gene for aspartoacylase has been cloned and two mutations predominate among Ashkenazi Jewish individuals with Canavan disease and account for more than 98% of the Ashkenazi Jewish patients. The mutations among other ethnic groups are more diverse. The carrier frequency for the two common mutations among Ashkenazi Jews was found to be surprisingly high, 1:37. Screening for carriers is now common practice for this population. A knock-out mouse for Canavan disease is being genetically engineered in our laboratory. The mouse model will allow for development of strategies for gene therapy.
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PMID:Spongy degeneration of the brain, Canavan disease: biochemical and molecular findings. 1070 28


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