Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026838 (spasticity)
 6,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Co-contraction of antagonist muscles is characteristic of spasticity arising from perinatal brain damage but not in spasticity occurring after brain damage in adulthood. Such co-contraction is a normal feature of early post-natal motor development. Heteronymous, monosynaptic Group Ia projections from biceps brachii to both the antagonist triceps brachii and to other synergist and non-synergist muscles of the upper limb occur in the newborn baby and become restricted during the first 4 years to motor neurons of primarily synergistic muscles. Longitudinal and cross-sectional studies have been performed to test the hypothesis that inappropriate heteronymous excitatory projections persist in children with perinatal brain damage who develop spasticity. Subjects with spasticity, from brain damage acquired in adulthood were also studied to determine if these projections simply become unmasked as part of spasticity, independent of the age of occurrence of the brain damage. Twenty-nine healthy newborn babies and 29 at high risk for cerebral palsy, 12 of whom developed spastic quadriparesis, were studied longitudinally for 4 years. Thirty-eight subjects, aged 8-30 years, with spasticity of perinatal origin (11 hemiplegic, 11 quadriplegic, 16 with Rett syndrome) and 11 subjects with stroke in adulthood and spastic hemiplegia were also studied. The results were compared with those obtained in 372 normal subjects aged from birth to 55 years. Small taps were delivered to the tendon of biceps brachii using an electromechanical tapper. Surface EMG was recorded from biceps and triceps brachii, pectoralis major and deltoid. In the longitudinal study, those developing spastic quadriparesis showed persistent low thresholds for the homonymous phasic stretch reflex, which had abnormally short onset latencies. There was persistence of short onset heteronymous excitatory responses in triceps brachii, while a normal pattern of restriction of heteronymous responses to pectoralis major and deltoid occurred. The same pattern was observed in older subject groups with spasticity of perinatal origin. In adults with hemiplegia following stroke the threshold of the homonymous phasic stretch reflex was low, but it had a normal onset latency. There was no evidence of abnormal heteronymous excitatory responses. In conclusion, exaggerated excitatory responses to primary muscle afferent input were observed in the homonymous (biceps brachii) and antagonist (triceps brachii) motor neurons in subjects with spasticity arising from perinatal brain damage. They are likely to play an important role in the predominant co-contraction of agonist/antagonist muscles during voluntary movement observed in subjects with spastic cerebral palsy.
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PMID:Abnormal development of biceps brachii phasic stretch reflex and persistence of short latency heteronymous reflexes from biceps to triceps brachii in spastic cerebral palsy. 987 88

We report 5 girls presenting Rett syndrome. All of them were from south Tunisia. They fulfilled the Rett syndrome diagnosis criteria (The Rett syndrome diagnosis criteria work group, 1988). Pregnancy, birth and psychomotor development during the first year of live were normal. The mean age at the onset was 19.8 +/- 2.5 months. The two revealing symptoms were psychomotor regression (3 cases) and epilepsy (2 cases). They were admitted to our ward at a mean age of 4.7 +/- 1.5 years. Clinical presentation was typical of Rett syndrome. Mental retardation, stereotypic hand movement (hand washing/wringing or clapping/tapping) and loss of purposeful manual skills were noted in all cases. Gait was apraxic and increase of head circumference was slowed. Additional features included, respiratory dysfunction (episodic hyperventilation and breath-holding), epilepsy, scoliosis (4 cases), growth retardation and spasticity (3 cases). Electroencephalography showed slow activity with multifocal epileptiform abnormalities. Sleep enhanced these EEG abnormalities. MRI and CT-scan disclosed non specific cortical and sub-cortical atrophy. All cases were isolated and parents were consanguineous in 3 cases. Rett syndrome is relatively frequent in Europe, but in Tunisia this disease remains rare and certainly underdiagnosed.
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PMID:[Rett's syndrome: report of 5 cases in Tunisia]. 1060 40

Heterozygous mutations in the X-linked MECP2 gene cause Rett syndrome, a severe neurodevelopmental disorder of young females. Only one male presenting an MECP2 mutation has been reported; he survived only to age 1 year, suggesting that mutations in MECP2 are male lethal. Here we report a three-generation family in which two affected males showed severe mental retardation and progressive spasticity, previously mapped in Xq27.2-qter. Two obligate carrier females showed either normal or borderline intelligence, simulating an X-linked recessive trait. The two males and the two obligate carrier females presented a mutation in the MECP2 gene, demonstrating that, in males, MECP2 can be responsible for severe mental retardation associated with neurological disorders.
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PMID:A mutation in the rett syndrome gene, MECP2, causes X-linked mental retardation and progressive spasticity in males. 1098 43

The Rett syndrome (RS) is a peculiar, sporadic, atrophic disorder, almost entirely confined to females. After the first six months of life there is developmental slowing with reduced communication and head growth for about one year. This is followed by a rapid destructive stage with severe dementia and loss of hand skills (with frequent hand wringing), apraxia and ataxia, autistic features and irregular breathing with hyperventilation. Seizures often supervene. Subsequently there is some stabilization in a pseudo-stationary stage during the preschool to school years, associated with more emotional contact but also abnormalities of the autonomic and skeletal systems. After the age of 15-20 years, a late motor deterioration occurs with dystonia and frequent spasticity but seizures become milder. RS has generally been considered an X-linked disorder in which affected females represent a new mutation, with male lethality. Linkage studies suggested a critical region at Xq28. In 1999, mutations in the gene MECP2 encoding X-linked methyl cytosine-binding protein 2 (MeCP2) were found in a proportion of Rett girls. This protein can bind methylated DNA. Analyses are leading to much further investigation of mutants and their effects on genes. Neuropathological and electrophysiological studies of RS are described. Description of neurometabolic factors includes reduced levels of dopamine, serotonin, noradrenaline and choline acetyltransferase (ChAT) in brain, also estimation of nerve growth factors, endorphin, substance P, glutamate and other amino acids and their receptor levels. The results of neuroimaging are surveyed, including volumetric magnetic resonance imaging (MRI) and positron emission tomography (PET).
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PMID:Rett syndrome: review of biological abnormalities. 1125 89

Mutations in the MECP2 (methyl-CpG-binding protein 2) gene are known to cause Rett syndrome, a well-known and clinically defined neurodevelopmental disorder. Rett syndrome occurs almost exclusively in females and for a long time was thought to be an X-linked dominant condition lethal in hemizygous males. Since the discovery of the MECP2 gene as the cause of Rett syndrome in 1999, MECP2 mutations have, however, also been reported in males. These males phenotypically have classical Rett syndrome when the mutation arises as somatic mosaicism or when they have an extra X chromosome. In all other cases, males with MECP2 mutations show diverse phenotypes different from classical Rett syndrome. The spectrum ranges from severe congenital encephalopathy, mental retardation with various neurological symptoms, occasionally in association with psychiatric illness, to mild mental retardation only. We present a 21-year-old male with severe mental retardation, spastic tetraplegia, dystonia, apraxia and neurogenic scoliosis. A history of early hypotonia evolving into severe spasticity, slowing of head growth, breathing irregularities and good visual interactive behaviour were highly suggestive of Rett syndrome. He has a de novo missense mutation in exon 3 of the MECP2 gene (P225L). The clinical spectrum and molecular findings in males with MECP2 mutations are reviewed.
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PMID:Neurodevelopmental disorders in males related to the gene causing Rett syndrome in females (MECP2). 1261 69

Intrathecal baclofen infusions have proven to be effective for management of spasticity during the last two decades. Efficacy of intrathecal baclofen for spasticity of spinal origin has been well established and has shown promise in treatment of spasticity that is not spinal in origin. Rett syndrome is a neurodevelopmental disorder primarily affecting girls and women. Manifested in the advanced stages of this syndrome is increased spasticity leading to functional decline. Presented is a case report of a 32-yr-old white woman with Rett syndrome, diagnosed before the age of 2 yr, and significant spasticity that was successfully managed with intrathecal baclofen. After placement of an intrathecal baclofen pump, the dose was increased slowly during 1 yr to 800 microg/day with good clinical response. There was observed a significant decrease in upper and lower limb Ashworth scores, from an average of 3-4 to 2-3, during this 1-yr period. The decrease in spasticity in this patient eventually led to improved range of motion, positioning, skin care, hygiene, and quality of life. Intrathecal baclofen is an effective option in managing severe spasticity from Rett syndrome.
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PMID:Intrathecal baclofen for spasticity management in Rett syndrome. 1281 44

Loss-of-function mutations of the MECP2 gene at Xq28 are associated with Rett syndrome in females and with syndromic and nonsyndromic forms of mental retardation (MR) in males. By array comparative genomic hybridization (array-CGH), we identified a small duplication at Xq28 in a large family with a severe form of MR associated with progressive spasticity. Screening by real-time quantitation of 17 additional patients with MR who have similar phenotypes revealed three more duplications. The duplications in the four patients vary in size from 0.4 to 0.8 Mb and harbor several genes, which, for each duplication, include the MR-related L1CAM and MECP2 genes. The proximal breakpoints are located within a 250-kb region centromeric of L1CAM, whereas the distal breakpoints are located in a 300-kb interval telomeric of MECP2. The precise size and location of each duplication is different in the four patients. The duplications segregate with the disease in the families, and asymptomatic carrier females show complete skewing of X inactivation. Comparison of the clinical features in these patients and in a previously reported patient enables refinement of the genotype-phenotype correlation and strongly suggests that increased dosage of MECP2 results in the MR phenotype. Our findings demonstrate that, in humans, not only impaired or abolished gene function but also increased MeCP2 dosage causes a distinct phenotype. Moreover, duplication of the MECP2 region occurs frequently in male patients with a severe form of MR, which justifies quantitative screening of MECP2 in this group of patients.
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PMID:Duplication of the MECP2 region is a frequent cause of severe mental retardation and progressive neurological symptoms in males. 1608 Jan 19

Individuals with Rett syndrome (RS) present a vast array of orthopedic and neurological difficulties. Typical problems, which may need to be addressed, when treating this population are functional limitations, low cardiovascular capacity, hypotonia, ataxia, apraxia, loss of transitional movements, spasticity, scoliosis and/or kyphosis, loss of ambulation, loss of hand function, foot deformities, and spatial disorientation. Coping with such difficulties and overcoming the associated limitations carry a wearisome task for the individual with Rett as well as for her family. An informed and intensely applied physical therapy regime can help the child and the family cope and even overcome the above-mentioned limitations. The present article presents some insights regarding the intervention with individuals with RS, an overview of typical neuromuscular problems associated with RS, and appropriate suggestions pertaining to clinical intervention that have been found to contribute to this population's well-being. The information presented is mainly based on the clinical knowledge of the authors.
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PMID:Physical therapy intervention for individuals with Rett syndrome. 1704 20

Loss-of-function mutations of the MECP2 gene are the cause of most cases of Rett syndrome in females, a progressive neurodevelopmental disorder characterized by severe mental retardation, global regression, hand stereotypies, and microcephaly. On the other hand, gain of dosage of this gene causes the MECP2 duplication syndrome in males characterized by severe mental retardation, absence of speech development, infantile hypotonia, progressive spasticity, recurrent infections, and facial dysmorphism. Female carriers of a heterozygous duplication show a skewed X-inactivation pattern which is the most probable cause of the lack of clinical symptoms. In this paper, we describe a girl with a complex de novo copy number gain at Xq28 and non-skewed X-inactivation pattern that causes mental retardation and motor and language delay. This rearrangement implies triplication of the MECP2 and IRAK1 genes, but it does not span other proximal genes located in the common minimal region of patients affected by the MECP2 duplication syndrome. We conclude that the triplication leads to a severe phenotype due to random X-inactivation, while the preferential X chromosome inactivation in healthy carriers may be caused by a negative selection effect of the duplication on some proximal genes like ARD1A or HCFC1.
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PMID:De novo interstitial triplication of MECP2 in a girl with neurodevelopmental disorder and random X chromosome inactivation. 2193 80

Rett syndrome (RTT) is a severe neurodevelopmental disorder primarily affecting females that has an incidence of 1:10000 female births, one of the most common genetic causes of severe mental retardation in females. Development is apparently normal for the first 6-18 months until fine and gross motor skills and social interaction are lost, and stereotypic hand movements develop. Progression and severity of the classical form of RTT are most variable, and there are a number of atypical variants, including congenital, early onset seizure, preserved speech variant, and "forme fruste." Mutations in the X-linked gene methyl-CpG-binding protein 2 (MECP2) involve most of the classical RTT patients. Mutations in cyclin-dependent kinase like 5 (CDKL5) and FoxG1 genes have been identified in the early onset seizure and the congenital variants respectively. Management of RTT is mainly symptomatic and individualized. It focuses on optimizing each patient's abilities. A dynamic multidisciplinary approach is most effective, with specific attention given to epileptic and nonepileptic paroxysmal events, as well as scoliosis, osteoporosis, and the development of spasticity, which can have a major impact on mobility, and to the development of effective communication strategies for these severely disabled individuals.
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PMID:Genetically determined encephalopathy: Rett syndrome. 2362 76


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