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

The role of spinal cord injury in the pathogenesis of abnormal motor signs (depressed tone and reflexes) following severe perinatal hypoxia-ischemia was prospectively evaluated by clinical, electrophysiological, and neuropathological examinations in 18 asphyxiated neonates. All infants had an abnormal mental status (lethargy or coma), and seizures were present in 12. Neuromuscular examinations revealed hypotonia or flaccidity and hyporeflexia or areflexia in all infants. Neuropathological examinations of the cerebrum and spinal cord were conducted in the 12 neonates who expired. Cerebral pathological findings included cortical neuronal necrosis in 10 of 12 and subcortical white matter injury in 5 of 12. All infants with coma or seizures displayed diffuse cortical injury, but no injury conformed to a parasagittal "watershed" distribution. Spinal cord gray matter displayed prominent ischemic necrosis in 5 patients who were typically flaccid and areflexic. Electromyographic examinations of all 6 survivors were abnormal, consistent with recent injury to the lower motor neuron above the level of the dorsal root ganglion. We conclude that ischemic injury to anterior horn cells within spinal cord gray matter is relatively common among hypotonic-hyporeflexic neonates following severe perinatal hypoxia-ischemia. Although the acute neurological syndrome of neonatal asphyxia is often overshadowed by prominent cerebral signs such as coma and seizures, the motor abnormalities may be partially attributed to concurrent spinal cord injury.
 ...
PMID:Hypoxic-ischemic spinal cord injury following perinatal asphyxia. 291 67

This article presents the results of a multiple baseline design, across subjects, to assess the effect of vibratory stimulation on head-erect behavior in subjects who were prone. The subjects were three children with severe multiple handicaps whose mean age was 2 years 4 months and whose conditions included seizures and muscle tone disorders. Frequency of head lifts and cumulative duration of head-erect behavior were recorded during three-minute sessions with the subjects positioned prone on their forearms over a wedge. After baseline observations were recorded, vibration was applied to the paraspinal muscles of the neck and upper back for the first two minutes of each intervention session. In addition, electromyographic activity was recorded for a three-minute session at least once during both the baseline and intervention conditions. Results of the study demonstrated an increase in the cumulative duration of head-erect behavior for the three subjects and an accompanying increase in EMG activity during muscle vibration. The diversity of handicapping conditions (ie, seizures, hypertonia, and hypotonia) appeared to have no effect on the benefits received from muscle vibration for these subjects. Limitations of the study and implications for future research are discussed.
 ...
PMID:Head-erect behavior among three preschool-aged children with cerebral palsy. 295 13

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.
 ...
PMID:Fatal infantile cytochrome c oxidase deficiency: decrease of immunologically detectable enzyme in muscle. 298 57

At the eve of its mapping, the pre-molecular picture of the FG syndrome is heavily biased towards the severe end of the phenotypic spectrum because present knowledge is largely based on propositi. It is an X-linked, incompletely recessive, complexly pleiotropic syndrome with considerably variable expressivity. Though a true multiple congenital anomalies/mental retardation (MCA/MR) syndrome, severe malformations are uncommon and involve mostly the anus (60%) and non-colonic GI defects (33%), hypospadias (25%), cleft palate (6%), rarely a congenital heart defect. The complex CNS dysfunctions of congenital hypotonia and all of its sequelae, MR, and occasional seizures, must be attributed to a developmental CNS defect which is rarely demonstrated at pre-mortem, and which is known to involve agenesis of the corpus callosum in some 25% of appropriately studied patients (mostly propositi). Thus, the diagnosis is largely made on a specific constellation of minor anomalies and mild malformations in a hypotonic boy with severe constipation and a very characteristic facial appearance and behavioral phenotype. In about 1/3 of cases, carrier manifestations may be detected physically. New hemizygote manifestations seen in this review of 5 new patients include abnormal eruption of teeth, diastasis between upper central incisors, apparent gynecomastia, cleft lip, and nasolacrimal and helicine fistulae. Only a half hundred or so FG syndrome patients are known, but we suspect the syndrome is much more common than realized, and because of the unfortunate recurrence risk potential, deserves careful consideration in every appropriate case. RFLP mapping studies are urged in order to aid diagnosis of "mild" cases, and prenatal and carrier detection.
 ...
PMID:FG syndrome update 1988: note of 5 new patients and bibliography. 305 62

In order to evaluate significance and frequency of valproic acid (VPA)-induced hyperammonemia we measured venous serum ammonia, SGOT, G-GT, platelets and antiepileptic drug levels in three groups of subjects: 1.) 30 pediatric patients treated with VPA, alone or in combination 2.) 30 healthy age and sex matched subjects 3.) 30 pediatric unselected patients treated with various antiepileptic drugs except VPA. In the VPA group serum ammonia was significantly (p less than 0.01) higher than in controls and in the group 3. Patients on VPA-polytherapy had significantly higher serum ammonia values than patients on VPA-monotherapy (p less than 0.01). Hyperammonemia was found in 8 (27%) VPA-treated patients. A syndrome consisting of lethargy, stupor, hypotonia and increased seizure activity developed in 3 patients on VPA-therapy of whom two showed hyperammonemia. After discontinuing VPA this syndrome disappeared in all three cases. There was no direct correlation between VPA and ammonia levels. The etiology of hyperammonemia in VPA treated patients is not yet fully explained. It may be related to the fatal VPA induced hepatic failure reported in the literature. Some risk factors which may facilitate hepatic injury during VPA therapy (young age, co-medication, polytherapy, infectious disease, protein overload, low caloric intake) are discussed and some practical consequences are indicated.
 ...
PMID:[Hyperammonemia in valproate therapy in children and adolescents]. 308 61

We report 14 cases of a severe familial leukoencephalopathy among native North American Indian infants in northern Quebec and Manitoba. Affected infants have hypotonia and mild motor delay, followed by seizures, hypotonia or spasticity, eye deviation, and abnormal posture during a febrile illness around 6 months of age. Death follows a rigid, vegetative state that manifests days to months after disease onset and is marked in some cases by prominent autonomic disturbances, blindness, and cessation of head growth. Symmetrical hemispheric white matter lucencies and diffuse hypomyelination of the cerebral hemispheres and brainstem are the radiological and pathological hallmarks. This disease differs from the known diseases of cerebral myelin. An autosomal recessive pattern of inheritance awaits statistical confirmation. The proposed cause is a delay in development or abnormal turnover of central nervous system myelin.
 ...
PMID:Leukoencephalopathy among native Indian infants in northern Quebec and Manitoba. 323 51

18F fluorodeoxyglucose (18FDG) and positron tomography (PT) were used in 20 full term babies with seizures or hypotonia to describe regional cerebral glucose metabolism. Among babies with seizures, birth asphyxia was the most common cause. PT was performed at age 6-17 days. One hour before PT, 18FDG (50-100 microCi/kg) was injected intravenously. Ten or more PT sections were obtained in each infant. The areas of the brain that were metabolically the most active were the cortex and the thalami. Six cortical areas and a white matter reference area were selected for analysis of relative rates of glucose metabolism as indicated by relative rates of fluorine-18 activity. Cortical fluorine-18 activity was highest in the pericentral (sensorimotor) regions and lowest in the frontal regions. The overall cortex/white matter ratio for fluorine-18 activity averaged 1.78 +/- 0.44 (SD). Four patterns of regional cerebral glucose metabolism were distinguished: 1) bilateral symmetry, 2) loss of metabolic definition, 3) hemispheral asymmetry, 4) focal hyper- or hypometabolism. Patterns 1) and 2) correlated with a history of birth asphyxia, a diagnosis of hypoxic-ischemic encephalopathy and the absence of focal echoes on cranial ultrasound. Hypodense areas on CT could be associated with either high or low fluorine-18 relative activity on PT. The prognostic significance of the presently reported patterns of cerebral glucose metabolism remains to be determined.
 ...
PMID:Patterns of cerebral glucose metabolism using 18FDG and positron tomography in the neurologic investigation of the full term newborn infant. 326 90

There are several clinically distinct forms of neuronal ceroid lipofuscinosis whose presentation and pathology are usually homogeneous within families. Several atypical variants have also been reported. We have studied an inbred sibship in which neuronal ceroid lipofuscinosis appeared to present in two completely different ways. In the proband, the course was compatible with a somewhat atypical juvenile variant. Ataxia and spasticity started at 4.5 years, followed by blindness with optic atrophy, intractable seizures, dementia, and death at 14 years. Atypical features included areflexia, hypotonia, and ataxia. Electron microscopic studies of her skin and her rectal ganglion cells showed lucent, dense, and fingerprint inclusions that were also found in the central nervous system at autopsy. Her brother and sister developed difficulty walking at ages 8.5 and 10.5 years and are alive at 24 and 18 years. They presented with slowly progressive spinocerebellar degeneration with sensorimotor neuropathy without dementia, seizures, or visual impairment. Lysosomal enzymes and lipoprotein analysis were normal in all three siblings and their parents. Elevated dolichol in the urine and lucent, dense, and fingerprint inclusions in skin, cutaneous nerve, buffy coat lymphocytes in both siblings and in the sural nerve of the brother suggest that their disease may represent a novel phenotype of neuronal ceroid lipofuscinosis. While it is possible that two different recessive genes may be segregating in this consanguineous family, we cannot dismiss the possibility that variability of gene expression may account for the divergent phenotypes.
 ...
PMID:Spino-cerebellar degeneration with polyneuropathy associated with ceroid lipofuscinosis in one family. 342 77

Septo-optic dysplasia (De Morsier's syndrome) is a common cause of congenital optic nerve hypoplasia. Associated abnormalities such as hypothalamic/pituitary dysfunction, hypotonia or spasticity, may result in affected children presenting for surgical procedures under general anaesthesia. A 3.5-year-old boy with the undiagnosed condition had his Achilles tendons elongated under an uncomplicated general anaesthetic. The postoperative period was complicated by coma and a major convulsive seizure which responded to glucose and steroids. The importance of awareness of this condition in short children with poor visual acuity who require general anaesthesia is stressed, and the presenting features of seven other cases are demonstrated.
 ...
PMID:Anaesthesia and septo-optic dysplasia. Implications of missed diagnosis in the peri-operative period. 343 62

Six Italian university centers have taken part in the Perinatal Preventive Medicine Project of the National Research Council since 1973. In this report the preliminary data on neonatal neurological disorders of 38775 single not malformed infants are presented. Neurological abnormality has been defined by the presence of at least one of the following symptoms: seizures, hypertonia, hypotonia, apneic spells. The relative frequencies of seizures vary from a minimum of 0.28% to a maximum of 0.75% in the six centers. The frequencies of the other symptoms demonstrate a greater variability among centers. Males are more affected than females. The relative frequency of neurological abnormalities is higher among babies with low birthweight, short gestational age or retarded intrauterine growth. Also, the frequency of seizures is higher among babies with low birthweight or retarded intrauterine growth while the relationship between seizures and gestational age is not clear.
 ...
PMID:[Neurologic pathology in the neonatal period: relation to birth weight and gestational age]. 357 28


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>