Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The gene for SCA2 has been mapped to chromosome 12q23-q24.1, but the mutant gene remained to be identified. When studying a Japanese family with SCA2, we noted that clinical features and disability varied among patients, with the central feature being progressive ataxia-slow eye movement-hyporeflexia syndrome. Additional symptoms were parkinsonism with minor cerebellar deficits, and severe ataxia with choreoathetosis. Our experience plus related literature documentation indicates that choreoathetosis is not so rare at the advanced stage of the disease, with onset at an early age, and that the variety of SCA2 phenotype depends on age at onset and duration of the disorder.
 ...
PMID:Central phenotype and related varieties of spinocerebellar ataxia 2 (SCA2): a clinical and genetic study with a pedigree in the Japanese. 899 21

Some of the most common diseases in humans occur intermittently in people who are otherwise healthy and active. Such disorders include migraine headache, epilepsy, and cardiac arrhythmias. Because electrical signals are critical to the function of neurons, muscle cells, and heart cells, proteins that regulate electrical signaling in these cells are logical sites where abnormalities might lead to disease. All of these diseases have prominent genetic components. Difficulty in understanding these diseases arises from the complexity of the clinical phenotypes as well as from the genetic heterogeneity that is almost certain to exist. Therefore, early work in may laboratory was aimed at understanding the pathogenesis of rare disorders that are similar in their episodic nature. These disorders of muscle (the periodic paralyses), lead to attacks of weakness that occur intermittently in otherwise normal people. We, and others, have shown that hyperkalemic periodic paralysis (hyperKPP) and paramyotonia congenita (PC) result from mutations in a gene encoding a skeletal muscle sodium channel. We have also shown that hypokalemic periodic paralysis (hypoKPP) is caused by mutations in a gene encoding a voltage-gated calcium channel. The characterization of these diseases as channelopathies has served as a paradigm for other episodic disorders. One example is periodic ataxia, which results from mutations in voltage-gated potassium calcium channels. Long QT syndrome, an episodic cardiac dysrhythmia syndrome, is known to result from mutations in either voltage-gated sodium or potassium channels. We have recently mapped genes that cause a familial paroxysmal dyskinesia (non-kinesiogenic paroxysmal dystonia/choreoathetosis) in humans and a reflex epilepsy in mice. The similarities among all these disorders, including their episodic nature, precipitating factors, and therapeutic responses, are striking. Understanding gained from work in these rare monogenic episodic disorders is not only allowing characterization of the molecular and physiologic basis of these diseases, but may ultimately shed light on our understanding of the pathophysiology of more common and genetically complex disorders of the central nervous system.
 ...
PMID:Channelopathies: ion channel disorders of muscle as a paradigm for paroxysmal disorders of the nervous system. 919 7

We report a 60-year-old woman with progressive ataxia, myoclonus, choreoathetosis, and dementia. She was well until 27 years of the age when she noted an onset of gait disturbance and speech disturbance. She noted abnormal involuntary movements in her four limbs at 42 years of the age. Her symptoms had progressively become worse and she fell down frequently by her 52 years of the age. In addition, her family members noted gradual decline in her intelligence. She was admitted to our hospital in February of 1993 when she was 57-year-old. On admission, she showed dementia, scanning speech, ataxic gait, limb ataxia, action myoclonus, and choreic movements which involved her four limbs. Deep tendon reflexes were slightly exaggerated in the lower limbs; no Babinski sign was noted. Sensation was intact. Laboratory findings were unremarkable. Cerebral MRI revealed atrophy of the cerebellar cortex, superior cerebellar peduncle, brain stem, and the cerebral cortex; the third ventricle and the lateral ventricles were dilated; furthermore, T2-high signal lesions were seen in the cerebral white matter and in the pontine base. Her clinical course was one of the progressive deterioration of her ataxia, involuntary movements, and dementia. She expired on April 24, 1996 when she was 60-year-old. She was discussed in a neurologic CPC and the chief discussant arrived at the conclusion that the patient had dentatorubral-pallidoluysian atrophy. A minor opinion was that she might have had myoclonus epilepsy with ragged-red fibers. Postmortem examination revealed atrophy, gliosis, and neuronal loss in the external segment of the globus pallidus, subthalamic nucleus, red nucleus, and in the dentate nucleus. In addition, the gracil and cuneiform nuclei showed neuronal loss and spheroid formation; the spinocerebellar tracts were retained. The substantia nigra and the locus coeruleus were intact. No ragged-red fibers were seen in the muscle biopsy specimen taken in February, 1993. The neuropathologic findings were consistent with the diagnosis of dentatorubral-pallidoluysian atrophy.
 ...
PMID:[(Neurological CPC.55). A 60-year-old woman with progressive cerebellar ataxia, myoclonus, and dementia]. 923 57

Clinical details are given of different types of episodic ataxia: type 1, with myokymia, and attacks which usually last a few minutes, and may occur several times a day, and treatment with acetazolamide can reduce the number of attacks; type 2, with interictal nystagmus, and attacks which last for several hours to a day or more, and treatment with acetazolamide is very effective; paroxysmal choreoathetosis with episodic ataxia, with attacks lasting for about 20 min and occurring at varying intervals; and familial hemiplegic migraine, with transient hemiplegia presenting during the aura of a migraine headache, the symptoms improving on treatment with acetazolamide. Their inheritance is of dominant type; and the gene for type 1 is mapped to chromosome 12p near to a cluster of potassium channel genes, and that for type 2 and for familial hemiplegic migraine to chromosome 19p near to calcium channel genes. The differential diagnosis from other conditions with a periodic symptomatology is discussed, especially from a number of metabolic disorders. Treatment is effective for many of these, and the treatment of the episodic ataxias with acetazolamide can sometimes have a dramatic effect. The possible role of the channelopathies in the causation of some periodic neurological disorders is considered; with the expectation that further research will improve the identification of specific diseases, and lead to more effective treatment.
 ...
PMID:Episodic ataxia and channelopathies. 953 53

A variety of cerebral insults can result in static encephalopathy with developmental delays and relatively fixed motor and cognitive deficits. We describe two boys with static encephalopathy who experienced recurrent episodes of generalized, violent ballism seemingly provoked by relatively minor infectious illnesses or surgical procedures. These episodes first began at ages 14 and 9 years, respectively. The baseline clinical states included relatively mild choreoathetosis plus cognitive impairment, as well as spasticity and/or ataxia. These episodes of ballism developed over hours, remained for weeks, and ultimately returned to baseline. Neuroleptics, anticonvulsants, and benzodiazepines were only partially beneficial; responses corresponded to the degree of sedation. Potential for self-injury or rhabdomyolysis/myoglobinuria led to the use of general anesthetics or neuromuscular blocking agents during selected episodes. Blood, urine, and cerebrospinal fluid studies, magnetic resonance imaging head scans, and electroencephalography revealed no diagnostic clues as to the precise causative factor precipitating these episodes.
 ...
PMID:Violent recurrent ballism associated with infections in two children with static encephalopathy. 1083 Apr 25

We present our analysis of 44 patients with alternating hemiplegia of childhood. The clinical course usually consisted of three phases. The first was dominated by abnormal eye movements and dystonic episodes, the second by hemiplegic spells and psychomotor regression, and the third by persistent developmental delay and fixed neurologic deficits. The age of onset was 0-54 months (mean = 7.9 +/- 13 months). The presenting signs included abnormal ocular movements in 65%, dystonia in 60%, and hemiplegia in 32%. Patients with an early onset of the disorder and an early appearance of hemiplegic spells faired the poorest developmentally. Developmental delay was present in 91%, ataxia in 68%, choreoathetosis in 50%, and seizures in 18%. Laboratory investigations suggested mitochondrial abnormalities and cerebrovascular dysfunction in several patients. Numerous therapies were largely ineffective. Flunarizine reduced the duration, severity, and frequency of the hemiplegic attacks in 78%. Patients who received flunarizine did not differ developmentally from those who did not. Our data suggest that flunarizine does not adversely affect and may favorably influence the outcome in patients with alternating hemiplegia of childhood. Additionally, the occurrence of autosomal-dominant cases of the syndrome, although rare, suggests that, in addition to mitochondrial dysfunction, genetic factors may be important.
 ...
PMID:Alternating hemiplegia of childhood: clinical manifestations and long-term outcome. 1102 Jun 38

Ataxia with oculomotor apraxia (ataxia-telangiectasia-like syndrome [AOA]; MIM 208920) is an autosomal recessive disorder characterized by ataxia, oculomotor apraxia, and choreoathetosis. These neurological features resemble those of ataxia-telangiectasia (AT), but in AOA there are none of the extraneurological features of AT, such as immunodeficiency, neoplasia, chromosomal instability, or sensitivity to ionizing radiation. It is unclear whether these patients have a true disorder of chromosomal instability or a primary neurodegenerative syndrome, and it has not been possible to identify the defective gene in AOA, since the families have been too small for linkage analysis. We have identified a new family with AOA, and we show that the patients have no evidence of chromosomal instability or sensitivity to ionizing radiation, suggesting that AOA in this family is a true primary cerebellar ataxia. We have localized the disease gene, by linkage analysis and homozygosity mapping, to a 15.9-cM interval on chromosome 9q34. This work will ultimately allow the disease gene to be identified and its relevance to other types of autosomal recessive cerebellar ataxias to be determined.
 ...
PMID:Autosomal recessive cerebellar ataxia with oculomotor apraxia (ataxia-telangiectasia-like syndrome) is linked to chromosome 9q34. 1102 12

We studied a 27-year-old woman who died after a 6-year history of progressive dementia, dystonia, ataxia, apraxia, spasticity, choreoathetosis, visual and auditory hallucinations, and optic atrophy. Magnetic resonance imaging showed decreased intensity in the globus pallidus, substantia nigra, and dentate nuclei in T2-weighted images, supporting the clinical diagnosis of neurodegeneration with brain iron accumulation type 1 (NBIA-1; formerly known as Hallervorden-Spatz syndrome). At autopsy the brain showed mild frontotemporal atrophy and discoloration of the globus pallidus and the substantia nigra pars reticularis. Histologically, features typical of NBIA-1 were found including widespread axonal spheroids and large deposits of iron pigment in the discolored regions. Additionally, excessive numbers of Lewy bodies (LBs) were found throughout all examined brain stem and cortical regions. LBs of both types, as well as Lewy neurites in this case of NBIA-1, were strongly labeled by antibodies against alpha-synuclein. These findings give further evidence that accumulation of alpha-synuclein is generally associated with LB formation, i.e., in Parkinson's disease, dementia with Lewy bodies and NBIA-1. The case presented here is particularly notable for its high number of LBs in all areas of the cerebral cortex.
 ...
PMID:Alpha-synuclein accumulation in a case of neurodegeneration with brain iron accumulation type 1 (NBIA-1, formerly Hallervorden-Spatz syndrome) with widespread cortical and brainstem-type Lewy bodies. 1104 80

We describe here familial dyskinesia and facial myokymia (FDFM), a novel autosomal dominant disorder characterized by adventitious movements that sometimes appear choreiform and that are associated with perioral and periorbital myokymia. We report a 5-generation family with 18 affected members (10 males and 8 females) with FDFM. The disorder has an early childhood or adolescent onset. The involuntary movements are paroxysmal at early ages, increase in frequency and severity, and may become constant in the third decade. Thereafter, there is no further deterioration, and there may even be improvement in old age. The adventitious movements are worsened by anxiety but not by voluntary movement, startle, caffeine, or alcohol. The disease is socially disabling, but there is no intellectual impairment or decrease in lifespan. A candidate gene and haplotype analysis was performed in 9 affected and 3 unaffected members from 3 generations of this family using primers for polymorphic loci closely flanking or within genes of interest. We excluded linkage to 11 regions containing genes associated with chorea and myokymia: 1) the Huntington disease gene on chromosome 4p; 2) the paroxysmal dystonic choreoathetosis gene at 2q34; 3) the dentatorubral-pallidoluysian atrophy gene at 12p13; 4) the choreoathetosis/spasticity disease locus on 1p that lies in a region containing a cluster of potassium (K+) channel genes; 5) the episodic ataxia type 1 (EA1) locus on 12p that contains the KCNA1 gene and two other voltage-gated K+ channel genes, KCNA5 and KCNA6; 6) the chorea-acanthocytosis locus on 9q21; 7) the Huntington-like syndrome on 20p; 8) the paroxysmal kinesigenic dyskinesia locus on 16p11.2-q11.2; 9) the benign hereditary chorea locus on 14q; 10) the SCA type 5 locus on chromosome 11; and 11) the chromosome 19 region that contains several ion channels and the CACNA1A gene, a brain-specific P/Q-type calcium channel gene associated with ataxia and hemiplegic migraine. Our results provide further evidence of genetic heterogeneity in autosomal dominant movement disorders and suggest that a novel gene underlies this new condition.
 ...
PMID:Familial dyskinesia and facial myokymia (FDFM): a novel movement disorder. 1131 Jun 26

The clinical, pathophysiological and genetic features of some of the familial (idiopathic) paroxysmal movement disorders are reviewed. The paroxysmal dyskinesias share features and therefore may have the same pathophysiological mechanisms as other episodic neurological disorders which are known to be channelopathies. Paroxysmal kinesigenic choreoathetosis/dyskinesias (PKC/PKD) is a condition in which brief and frequent dyskinetic attacks are provoked by sudden movement. Antiepileptics particularly carbamazepine are very helpful for this condition. PKC has similarities to episodic ataxia type 1 which is caused by mutations of the KCNA1 gene. PKC and a related disorder in which infantile convulsions are associated (ICCA syndrome) have recently been linked to the pericentromic region of chromososme 16 in the vicinity of some ion channel genes. Paroxysmal exercise-induced dystonia (PED) is a rare disorder manifesting as episodes of dystonia mostly affecting the feet induced by continuous exercise like walking or running. The pathophysiology of PED is unknown and antiepileptic drugs are generally unhelpful. In paroxysmal dystonic choreoathetosis/nonkinesigenic dyskinesias (PDC/PNKD) the attacks are of long duration and induced by a variety of factors including coffee, tea, alcohol and fatigue but not by sudden movement. The gene for familial PDC has been linked to chromosome 2q close to a cluster of ion channel genes. Paroxysmal nocturnal dyskinesia is now known to be a form of frontal lobe epilepsy in some cases which may be familial with an autosomal dominant inheritance and has been given the eponym ADNFLE. ADNFLE is a genetically heterogenous condition. Mutations of the neuronal nicotinic acetylcholine receptor gene that have chromosome 20q have been reported in some families with ADNFLE. However, another family with ADNFLE has been linked to chromosome 15 in the area of another nicotinic acetylcholine receptor gene. Thus the familial paroxysmal dyskinesias appear to be clinically and genetically heterogeneous.
 ...
PMID:Familial (idiopathic) paroxysmal dyskinesias: an update. 1134 27


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