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Query: UMLS:C0038379 (strabismus)
 9,317 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thirty-four children with lactic acidosis and Leigh encephalopathy due to cytochrome C oxidase (COX) deficiency distributed in 28 families have recently been identified in northeastern Quebec, particularly in the Saguenay-Lac-Saint-Jean (SLSJ) region. The segregation analysis was consistent with an autosomal recessive mode of inheritance. The incidence was estimated at 1/2,063 live births between 1979 and 1990, and the carrier rate was estimated at 1/23 inhabitants in SLSJ. In SLSJ, the places of origin of the COX-deficient children and their parents did not show a clustered nonuniform distribution. The genealogical reconstruction of 54 obligate carriers identified 26 ancestors common to all of them. Twenty-two were 17th-century Europeans, suggesting that the COX-deficient gene was introduced in the French-Canadian population by early settlers. These results support the hypothesis of a founder effect for COX deficiency in northeastern Quebec. Clinical findings are reported for 15 of these COX-deficient patients, age 6 mo to 11 years. Moderate developmental delay, hypotonia, ataxia, strabismus, and mild facial dysmorphism were frequent. Eleven children died in episodes of fulminant metabolic acidosis. The patients had elevated blood and cerebrospinal fluid lactate levels, decreased blood bicarbonate levels, and normal blood pH. Leigh disease and microvesicular steatosis of the liver were present in all affected patients for whom postmortem examination was performed. This biochemically uniform group of patients showed a wide range of clinical severity.
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PMID:Clinical, metabolic, and genetic aspects of cytochrome C oxidase deficiency in Saguenay-Lac-Saint-Jean. 839 91

To explore the structural basis for visuomotor deficits in infantile esotropia, we examined binocular connections and metabolic activity in the primary visual cortex of two strabismic macaque monkeys. The animals were documented to have onset of natural esotropia in early infancy. Behavioral testing showed that the animals had normal visual acuity in both eyes and the ocular motor deficits that characterize strabismus with onset in infancy. The neuronal tracer substance biotinylated-dextran-amine was injected into ocular dominance columns (ODC) in area V-1 (striate cortex), revealing a paucity of binocular connections between right-eye and left-eye ODCs. The metabolic label cytochrome-oxidase was used to stain neighboring right-eye and left-eye ODCs, revealing inequalities in metabolic activity compatible with interocular suppression. These results show that infantile esotropes have abnormalities of visual cortex structure that correlate with abnormalities in binocular behaviors.
J Pediatr Ophthalmol Strabismus
PMID:Neuroanatomic abnormalities of primary visual cortex in macaque monkeys with infantile esotropia: preliminary results. 853 Oct 39

A recent model for the development of the pattern of eye-dominance domains in primary visual cortex predicts that stimulus conditions during early visual life determine the spacing (or periodicity) of ocular dominance columns (ODC). The model predicts that normal binocular visual experience consists of highly correlated binocular stimulation and leads to relatively narrow ODC spacing, while abnormal binocular visual stimulation attendant with strabismus consists of non-correlated, incoherent, and asynchronous stimulation and leads to wider than normal ODC spacing. Evidence in support of the model has been presented for strabismus in the kitten. We tested the predictions of the model in normal monkeys and others subjected to various forms of abnormal visual experience during infancy. We identified and measured the inter-column spacing (or periodicity) in the V1 cortex of 19 adult monkeys (M. mulatta) using the cytochrome-oxidase (CO) histochemical method. There were no significant differences in the V1 inter-column spacing between normal adult monkeys (n=5) and other adult monkeys having had monocular-form deprivation (n=5), experimental anisometropia (n=5), or experimental strabismus (n=4) early in life. The quality of early binocular visual experience is not a significant determinant of the inter-column spacing in primate V1 cortex. Therefore, the model predicting an increase in the ODC periodicity with strabismus is not supported.
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PMID:Column spacing in normal and visually deprived monkeys. 986 Feb 66

The diagnosis of mitochondrial myopathy depends upon a constellation of findings, family history, type of muscle involvement, specific laboratory abnormalities, and the results of histological, pathobiochemical and genetic analysis. In the present paper, the authors describe the diagnostic approach to mitochondrial myopathies manifesting as extraocular muscle disease. The most common ocular manifestation of mitochondrial myopathy is progressive external ophthalmoplegia (PEO). To exclude myasthenia gravis, ocular myositis, thyroid associated orbitopathy, oculopharyngeal muscular dystrophy, and congenital fibrosis of the extraocular muscles in patients with an early onset or long-lasting very slowly progressive ptosis and external ophthalmoplegia, almost without any diplopia, and normal to mildly elevated serum creatine kinase and lactate, electromyography, nerve conduction studies and MRI of the orbits should be performed. A PEO phenotype forces one to look comprehensively for other multisystemic mitochondrial features (e.g., exercise induced weakness, encephalopathy, polyneuropathy, diabetes, heart disease). Thereafter, and presently even in familiar PEO, a diagnostic muscle biopsy should be taken. Histological and ultrastructural hallmarks are mitochondrial proliferations and structural abnormalities, lipid storage, ragged-red fibers, or cytochrome-C negative myofibers. In addition, Southern blotting may reveal the common deletion, or molecular analysis may verify specific mutations of distinct mitochondrial or nuclear genes.
Strabismus 2006 Jun
PMID:Extraocular mitochondrial myopathies and their differential diagnoses. 1676 Jan 17