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)

In order to approach the hitherto unknown brain involvement in the XYY syndrome five adult patients with this syndrome were studied clinically and pneumoencephalographically. Clinical manifestations included delayed difficulties of speech and learning, clumsiness, mild intention tremor, muscular hypotonia, convulsions, hyperactivity, distractibility, impulsiveness, weak mental control, psychosexual disturbances and a slight defect of intelligence. All five had committed crimes. Pneumoencephalograms showed general ventricular enlargement of mild or moderate degree. The enlargement of lateral ventricles was unilateral or asymmetrically bilateral. The suprapineal recess of the third ventricle was uniformly enlarged. Small cerebellum and enlarged fourth ventricle were the abnormal findings in the posterior fossa. No cortical abnormalities were found. The clinical and pneumoencephalographic findings suggest a slight non-progressive developmental disorder of the brain resembling the so-called minimal brain dysfunction syndrome. The XYY syndrome appears to be one cause of the male preponderance in minimal brain dysfunction syndrome and criminal psychopathy.
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PMID:Pneumoencephalographic and clinical findings of the XYY syndrome. 71 4

Human and animal experiments performed recently have resulted in a more detailed understanding of limb movement and body posture disorders associated with cerebellar dysfunction. The delay in movement initiation can be explained by a delay in onset of phasic motor cortex neural discharge owing to decreased input from the cerebellar hemispheres. Disorders of movement termination (dysmetria), which can occur for movements at proximal and distal joints, result from disturbances of the timing and intensity of antagonist electromyographic (EMG) activity necessary to break the movement. Disorders in velocity and acceleration of limb movements result from muscular activity that is smaller in amplitude and more prolonged. The cerebellum is important for control of constant force but not for generation of maximal force. Dysdiadochokinesia is explained by a combination of the above mentioned mechanisms. During complex movements in three-dimensional space, the cerebellum contributes to timing between single components of a movement, scales the size of muscular action, and coordinates the sequence of agonists and antagonists. The basic structure of motor programs is not generated in the cerebellum. Hypotonia can be observed only in acute cerebellar lesions. Cerebellar tremor appears to result from a central mechanism, but is modulated or provoked through increased long-loop EMG responses. The common assumption that cerebellar ataxia of stance does not improve with visual feedback is true only of vestibulocerebellar lesions, not for ataxia resulting from atrophy of the anterior lobe of the cerebellum.
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PMID:Pathophysiology of cerebellar ataxia. 158 45

A new patient with Leigh's syndrome (subacute necrotizing encephalomyelopathy due to pyruvate dehydrogenase complex deficiency) is presented. A Turkish boy of consanguinously married healthy parents developed progressive muscle weakness since infancy. At the age of 3 years he was unable to sit, stand or walk. Clinical examination showed general muscle weakness, hypotonia, muscle hypotrophy, bilateral ptosis, partial bilateral external ophthalmoplegia, nystagmus, intention tremor and hypoactive tendon reflexes. The EEG showed diffuse slowing, the cerebral CT scan disclosed mild hydrocephalus e vacuo. Motor nerve conduction velocity was slightly decreased, the EMG revealed signs of neuropathy. In the biopsied muscle only a mild hypotrophy of type 2 fibres was found, no abnormal mitochondria could be detected. The sural nerve was slightly abnormal: loss of large myelinated axons, loss of unmyelinated nerves. CSF protein was elevated to 80 mg/dl, protein electrophoresis revealed the pattern of markedly impaired blood-CSF barrier. Serum lactate and pyruvate were permanently elevated. In the urine the excretion of alanine was raised. The clinical state deteriorated during intercurrent infections; somnolence, vomiting and Cheyne-Stoke's respiration occurred. At the age of 3 1/2 years the child died of pneumonia. In the liver tissue a decreased activity of the pyruvate dehydrogenase complex was found. Neuropathological examination of the brain demonstrated wide-spread changes of Leigh's spongiform encephalopathy. Several enzyme deficiencies have hitherto been associated with Leigh's syndrome: This patients confirms earlier findings that a subgroup of Leigh's syndrome is caused by pyruvate dehydrogenase complex deficiency.
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PMID:[Leigh's subacute necrotizing encephalomyelopathy due to decreased activity of the pyruvate dehydrogenase complex]. 312 26

To elucidate the effects of cerebellar hemorrhage on the term neonate, neurodevelopmental assessments were conducted at a mean age of 32 months on six children. In addition to cerebellar hemorrhage, ventriculomegaly was present on each subject's initial computed tomographic scan. All were managed without surgical evacuation. Two patients required shunts for progressive ventriculomegaly. Five patients had follow-up computed tomography indicating mild atrophy of the superior anterior vermis of the cerebellum; however, none had abnormal ventricular size or abnormalities of the cerebrum. On detailed examination conducted between the ages of 18 and 48 months, five had hypotonia, truncal ataxia, and intention tremor; two had nystagmus. Only one patient walked independently. Intellectual performance of four patients was within the retarded range and two had mildly delayed development. Two patients had markedly disordered expressive language. These data suggest that term neonates surviving cerebellar hemorrhage have neurologic deficits related to the site of hemorrhage, and cognitive deficits related to more generalized cerebral insult.
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PMID:Cerebellar hemorrhage in the term neonate: developmental and neurologic outcome. 388 Apr 21

We report a nonprogressive neurological disorder in at least 11 Hutterites with healthy but consanguineous parents. In several of the affected, hypotonia was noted at birth. Retarded motor and mental development became apparent during the first year of life. The age of unsupported walking varied from 5-21 years. Consistent signs were unsteady, broadly based gait and stance, exaggerated deep tendon reflexes mainly in the lower limbs, and mild to moderate mental retardation. Variable signs were extensor plantar reflexes (9/11), short stature (-2SD in 8/11), strabismus (7/11), small muscle mass (6/11), mild intention tremor (3/11), cataracts (1/11), and epilepsy (1/11). CAT scans in two affected sisters showed slight enlargement of the fourth ventricle in one and hypoplasia of the cerebellum in both. The disorder is probably the same as that described earlier under the heading, dysequilibrium syndrome.
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PMID:Nonprogressive cerebellar disorder with mental retardation and autosomal recessive inheritance in Hutterites. 724 19

Seven children had congenitally small cerebella. Perinatal asphyxia was not a factor. Clinical signs in infancy were generalized muscular hypotonia, delayed development, truncal titubation, and intention tremor. Most had fixation nystagmus and esotropia. Three had seizures and an abnormal EEG. Pneumoencephalography in each case revealed a small cerebellum with prominent folia, large fourth ventricle, wide vallecula, large cisterna magna, and normal lateral and third ventricles. A computerized tomography scan in one case showed similar findings. One patient had an absent corpus callosum. One patient died at 2 1/2 years. The cerebellar hemispheres and vermis were small. Granular cells were absent throughout. Purkinje's cells were preserved, but had dendritic swellings with radiating fibrils. Cerebellar, pontine, and inferior olivary nuclei showed mild neuronal loss. The clinical and pathologic findings resemble those of animal models of cerebellar hypoplasia produced by fetal exposure to certain viruses, toxins, or repeated low doses of radiation. Cerebellar hypoplasia is a clinical syndrome of several causes, but with many symptoms and signs in common.
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PMID:Human cerebellar hypoplasia: a syndrome of diverse causes. 738 51

An electro-mechanical device has been used to measure muscle tone in 12 children with cerebellar ataxia and in 12 healthy children matched for age and sex. All the children also had their tone assessed clinically. The machine measurement showed that six (50%) of the 12 ataxic children had hypotonia, one was hypertonic, while five had normal tone. There was significant correlation between estimation of muscle tone by the machine and by clinical examination. The machine will serve as a valuable addition to other devices already being used to measure the other motor deficits encountered in children with cerebellar disease--such as devices that measure gait ataxia, truncal balance, intention tremor and incoordination of the limbs. It is re-emphasized that assessment or confirmation of clinical signs by reliable and reproducible instrumentation, offers a more objective basis for management and follow-up of patients, than clinical testing alone, and eliminates the often-encountered inter-tester discrepancies.
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PMID:Measurement of muscle tone in children with cerebellar ataxia. 806 75

This article attempts to describe a very unusual case of a boy aged 15, who has had intractable epileptic phenomena, mental retardation, megalocephaly, micrognathy, syndactyly, small tongue, hypoplastic genitalia, gynecomasty, obesity, and slight left body hemiatrophy. Neurologically the patient has had hypotonia of the lower limbs, cerebellar dysfunction including horizontal nystagmus, bilateral intention tremor, dysdiadokokinesia, gait ataxia. The clinical investigation revealed low plasma cholesterol and hypoplasia of the vermis in MRI. The epileptic phenomena were intractable and polymorphous. One should have thought that this is an unusual case of Smith-Lemli-Opitz syndrome associated with features of Joubert syndrome.
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PMID:Clinical case: vermis hypoplasia with features of Smith-Lemli-Opitz syndrome. 1736 27

Leigh syndrome (LS) is a subacute necrotizing encephalomyelopathy with a diverse range of symptoms, such as psychomotor delay or regression, weakness, hypotonia, truncal ataxia, intention tremor as well as lactic acidosis in the blood, cerebrospinal fluid or urine. Both nuclear gene defects and mutations of the mitochondrial genome have been detected in these patients. Here we report a 7-year-old girl with hypotonia, tremor, developmental delay and psychomotor regression. However, serum lactate level as well as brain magnetic resonance imaging were normal. Mutational analysis has revealed a novel mutation in exon 4 of COX15 gene (c.415C>G) which results in p.Leu139Val. Previous studies have demonstrated that COX15 mutations are associated with typical LS as well as fatal infantile hypertrophic cardiomyopathy. Consequently, clinical manifestations of COX15 mutations may be significantly different in patients. Such information is of practical importance in genetic counseling.
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PMID:Leigh syndrome associated with a novel mutation in the COX15 gene. 2695 37