PubMed Health⌕ Search

Biomedical subjects

K Digre

Publications and source records attributed to K Digre.

10 recordsLinked to original sources
PubMed2000

Neuro-ophthalmic complications of sarcoidosis.

Sarcoidosis is a systemic disorder that is caused by granulomatous changes of uncertain etiology and commonly has multiorgan involvement. Ocular involvement may occur in up to 32% of persons afflicted by sarcoid. The neuro-ophthalmic manifestations of sarcoid, in particular, are varied and may affect any portion of the visual system, including neural structures. Diagnosis is often difficult due to the fact that the clinical presentation can mimic other disorders, such as Multiple Sclerosis, and therefore a systematic approach to testing must be used once the diagnosis has been considered. The importance of diagnosing neuro-ophthalmic sarcoid lies in the fact that it is a treatable disease. The mainstay of treatment is corticosteroids although other immunosuppressive agents may be used. The long-term prognosis of neuro-ophthalmic sarcoid has not been studied in large patient populations, but the data that is available suggests that remission may occur in up to 47%.

Eye Diseases↗
PubMed1999

Habitat-specific genetic effects on growth rate and morphology across pH and water-level gradients within a population of the moss Sphagnum angustifolium (Sphagnaceae).

To study genetic adaptations in bryophytes on small ecological and spatial scales and to assess the adaptive significance of morphological trait variation, genotypes of Sphagnum angustifolium originating from habitats characterized by different pH and height above water table were clonally propagated and grown along the same gradients that exist in the field. Clones from ombrotrophic habitats grew consistently better ombrotrophically than clones from minerotrophic habitats and vice versa, suggesting that the genotypes were adapted to different pH levels. Genetic variation was found in several morphological traits, but habitat-specific genetic effects were detected only in length of spreading branches. Covariation between morphology and growth was generally environmentally induced. Positive and negative cross-environment genetic correlations suggested the presence of constraints on adaptive reaction norm evolution. The indications of small-scale genetic adaptations suggest either selective establishment of genotypes adapted to specific habitats, strong selective forces operating at the later stages of the life cycle, restricted gene flow over short distances, or a combination of these. In contrast to prevailing views, these results indicate that bryophytes are likely to respond genetically to small-scale environmental gradients.

Journal Article↗
PubMed1996

False-negative hydroxyamphetamine (Paredrine) test in acute Horner's syndrome.

PURPOSE: To describe a false-negative hydroxyamphetamine test. METHOD: Two patients with acute unilateral Horner's syndrome whose pupils initially dilated equally to hydroxyamphetamine had pharmacologic localization to the postganglionic nerve in the second week following the onset of symptoms. RESULTS: Neuroimaging confirmed the postganglionic location in both cases. CONCLUSION: Falsely negative localization with hydroxyamphetamine can occur during the first week after injury, during which time the function of the boutons at the presynaptic terminal is lost.

Acute Disease↗
PubMed1996

An expanded CAG repeat sequence in spinocerebellar ataxia type 7.

Expanded CAG repeat sequences have been identified in the coding region of genes mutated in several neurodegenerative disorders, including spinocerebellar ataxia type 1 and Machado-Joseph disease. In all disorders described to date the CAG expansion codes for an elongated polyglutamine chain. An increased polyglutamine chain size leads to a more severe disease, thus correlating with the genetic anticipation seen in repeat expansion disorders. Spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant spinocerebellar ataxia with anticipation and a progressive degeneration of the cerebellar cortex. Using repeat expansion detection (RED), a method in which a thermostable ligase is used to detect repeat expansions directly from genomic DNA, we have analyzed 8 SCA7 families for the presence of CAG repeat expansions. RED products of 150-240 bp were found in all affected individuals and found to cosegregate with the disease (P < 0.000001, n = 66), indicating strongly that a CAG expansion is the cause of SCA7. On the basis of a previously established correlation between RED product sizes and actual repeat sizes in Machado-Joseph disease, we were able to estimate the average expansion size in SCA7 to be 64 CAG copies.

Chromosome Mapping↗
PubMed1994

Usher's syndrome and multiple sclerosis. Review of an individual with Usher's syndrome with a multiple sclerosis-like illness.

We describe an individual with Type I Usher's syndrome and a multiple sclerosis-like illness. MRI scan showed vermian atrophy on T1-weighted images and multiple white matter lesions in the periventricular areas on T2-weighted images. Although MRIs demonstrating increased signal intensity on weighted images are reported in some individuals with Usher's syndrome, the cerebrospinal fluid findings are not described in these cases. In the present case, oligoclonal bands were present in the spinal fluid. The possibility of a linkage between the two diseases is raised.

Adult↗
PubMed1983

Color "amnesia" without aphasia.

Following an apparent left parietal CVA, a patient developed a severe and nearly complete color amnesia which was not associated with any disturbance in color vision or color perception. Like all previously reported cases with color amnesia, this patient was alexic but, unlike most previously reported cases, he was not aphasic.

Agnosia↗
PubMed1978

Depression and hemispheric functions: changes associated with unilateral ECT.

Nine depressed patients received ECT to the dominant (left) side along with nine matched depressed patients who received ECT to the non-dominant (right) side. Neuropsychological tests showed that the right hemispheric functions were more frequently abnormal as compared to left hemispheric (dominant) functions in the pre-ECT tests. ECTs delivered to either the right or left side improved right hemispheric functions when the depression was ameliorated. This study indicates that in depression right hemispheric functions are initially disturbed and ECT, instead of being deleterious to these functions, tends to improve them.

Depression↗
PubMedDate not supplied

Two neuro-ophthalmic episodes separated in time and space.

A-46-year-old woman with a prior history of a spontaneously resolving right central retinal artery occlusion presented with an acute right third order Horner's syndrome and vague ocular pain. Magnetic resonance angiography demonstrated a right internal carotid artery dissection. The dissection improved on anticoagulation therapy. Marfans syndrome or Ehlers-Danlos syndrome was suspected but ruled out by clinical criteria and skin biopsy respectively.

Anticoagulants↗