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M O'Kane

Publications and source records attributed to M O'Kane.

14 recordsLinked to original sources
PubMed1999

Mutation screening and genotype:phenotype correlation in familial hypercholesterolaemia.

The aim of this study was to develop a mutation screening protocol for familial hypercholesterolaemia (FH) patients and to assess genotype/phenotype effects in terms of pre-treatment lipid profiles and presentation of tendon xanthomata (TX). A total of 158 families with clinical definitions of possible (120) or definite (38) FH were studied using a tiered screening protocol. Mutations were identified in 52 families, 44 families showing 23 different LDLR gene defects and eight families showing the common Apo B100 gene defect R3500Q. LDLR defects were detected in various regions of the gene with 56% in the LDL binding domain (exons 2-6) and 37% in the EGF precursor homology domain (exons 7-14). The most common mutations were D461N(7), C210X(5), 932delA(5), and C163Y(4). Frameshift mutations accounted for 20% with nonsense 13%, mis-sense 35%, splice 3%, Apo B 13% and 2% large deletion, 13% of clinically definite FH remained undefined. In conclusion, DNA based diagnosis is possible in 79% (30/38) of clinically definite FH families and of the 120 possible FH families at the start of the screening program, 18% (22/120) now have defined mutations. Overall 60 families from the original 158 meet the clinical and/or genetic criteria for definite FH. Tendon xanthomata were present in only 58% (30/52) of genetically defined FH families, thus limiting its use as a strict diagnostic criteria. Families with low density lipoprotein receptor (LDLR) defects present with higher total and LDL cholesterol levels and a higher incidence of TX than do those with the common Apo B variant, and frameshift mutations appear to have the most severe presentation.

Electrophoresis, Agar Gel↗
PubMed1996

A novel single base deletion in the LDLR gene (211delG): Effect on serum lipid profiles and the influence of other genetic polymorphisms in the ACE, APOE and APOB genes.

A single base deletion (211delG) in the low density lipoprotein receptor (LDLR) gene was shown to cause familial hypercholesterolaemia (FH) in a large family from Northern Ireland. Twenty-four of 52 family members tested had this mutation, 13 of which were newly diagnosed. Mutation-positive individuals had significantly higher mean total-cholesterol (TC) and LDL-cholesterol (LDL-C) than those without 211delG. LDL-C was a more accurate indicator of disease status than TC. When TC levels alone were considered, in individuals over 16 years, a false negative rate (TC < 7.5 mmol/l) of 40% was found; however this fell to 13% based on inclusion of LDL-C levels. Individuals with coronary artery disease (CAD) had significantly higher TC levels than those without CAD and tended to have tendinous xanthomas (TX) and corneal arcus (CA). Generic polymorphisms in the angiotensin converting enzyme (ACE) and apolipoprotein (apo) B genes did not appear to be associated with lipid levels or with the clinical severity of the disease; however, the apo E epsilon4 allele did show a lipid-raising effect in individuals with the mutation.

Adolescent↗
PubMed1985

Monitoring at the Swiss Epilepsy Center.

Long-term monitoring facilities have proven irreplaceable in the investigation of epileptic patients as well as in the assessment of therapy. We describe an integrated monitoring system which has been in operation in our center for over 5 years. It includes long-term monitoring by means of a 21-channel EEG write-out and video taping, ambulatory monitoring using a 4-channel cassette as well as an intensive monitoring system combining 16-channel radio telemetered EEG with split-screen video technology. Technical equipment, organization, indications, applications and clinical results are presented in detail. The availability of an experienced team of specialists (neurologist, engineer, clinical pharmacologist, neuropsychologist) is a prerequisite for the optimal utilization of these facilities. With out integrated monitoring system we investigate an average of 550 patients/year. In over half the cases, the desired information can be provided, resulting in a direct therapeutic benefit. The additional value of these methods, especially of the intensive monitoring, lies also in the possibility of compiling new knowledge about semiology and electro-clinical correlation of epileptic seizures, possible trigger mechanisms and long-term therapeutic effects. This should help to better understand the underlying pathophysiology and to further reduce the number of epileptic patients not responding to therapy.

Ambulatory Care↗
PubMedDate not supplied

Fluoxetine in the treatment of obese type 2 diabetic patients.

In a 12-month randomly allocated double-blind trial in 19 obese Type 2 diabetic patients, fluoxetine 60 mg daily compared to placebo produced a significant fall in median body weight after 3 months (3.8 kg), 6 months (6.5 kg), 9 months (7.1 kg) and at 1 year (5.8 kg). Median fasting blood glucose and HbA1c levels fell significantly after 3 months (1.9 mmol l-1) and 1.7%, respectively) and 6 months (1.8 mmol l-1 and 1.7%) but neither showed a significant difference to placebo after 9 or 12 months therapy with fluoxetine. There were no significant changes in serum cholesterol levels in the year but patients on fluoxetine showed a significant fall in serum triglyceride level (0.5 mmol l-1) after 3 months therapy but not thereafter. Compared to placebo there was a significant fall in median energy intake on fluoxetine after 3 months (257 kcal day-1) and 6 months (199 kcal day-1) but this difference was not significant at 9 or 12 months. There was also a significant fall in carbohydrate intake after 3 months (30 g day-1) and 6 months (23 g day-1) on fluoxetine as well as a significant fall in carbohydrate intake expressed as a percentage of the total daily energy intake; 5.9% at 3 months, 6.1% at 6 months, and 4.0% at 9 months. There were no significant effects on protein or fat intake except a significant increase in the intake of fat expressed as a percentage of daily energy intake, 5.9% after 6 months. Two of the nine patients on fluoxetine dropped out of the study due to gastrointestinal side-effects. Fluoxetine might prove to be a useful adjunct therapy in obese Type 2 diabetic patients where short-term weight loss and fall in carbohydrate intake and an improvement in glycaemia are indicated.

Adult↗
PubMedDate not supplied

The axial spasm--the predominant type of drop seizure in patients with secondary generalized epilepsy.

In 45 patients suffering from secondary generalized epilepsy, we have recorded 239 drop seizures both by radio-telemetered EEG/split-screen video taping and polygraphically. Twenty of these patients had pure tonic drop seizures. Nine patients each had myoclonic-atonic or pure atonic seizures, whereas seven had slow falls that occurred during gradually developing tonic or akinetic seizures. We term the pure tonic drop seizure "axial spasm." It consists of a uniform pattern of movement lasting from 0.5 to 0.8 s and leading to a specific bearing characterized by a moderate flexion of the hips, the upper trunk, and the head. The arms are almost always involved being abducted, elevated and in a semiflexed position. A fall is provoked by the rapidity and violence of the flexion in the hips. The spasms can occur independently (pure axial spasm) or in connection with other seizure manifestations (combined axial spasm). In pure spasms, no disturbance of consciousness and no significant EEG changes--apart from a slight attentuation--are seen. In the combined axial spasms, distinct epileptic phenomena, in close connection with the axial spasms, can be observed, appearing either in the postspasm phase or in both the pre- and the afterphases. The prephase consists always of an absence and spike-and-wave activity. The onset of the spasm coincides with the last generalized spike, which is followed by a biphasic high-voltage slow wave. In the afterphases, various seizure patterns can be seen; quite characteristic are arrest states during which the patients are completely immobile and take up a postural-like or athetoid position. Almost as frequent are absences or absence-like states and tonic seizures. The afterphase can be compounded by two or three of these seizure patterns, the most common sequence of events in these cases being tonic--arrest state--absence. From the clinical and neurophysiological points of view, axial spasms can be regarded as a more mature form of infantile spasms. Clinical and experimental findings suppose a brainstem origin.

Adolescent↗
PubMedDate not supplied

[Alzheimer disease: hypotheses implicating apolipoproteins E].

The most promising discovery in the study of Alzheimer's disease (AD) markers is undoubtedly the implication of apolipoprotein E (apoE). The gene of this apoliprotein is located on chromosome 19 and is characterized by three common alleles epsilon 2, epsilon 3 and epsilon 4 giving raise to 6 genotypes and 6 protein phenotypes. ApoE is well known for its role in cholesterol transport. Different studies have been performed, giving major arguments in favor of an important role of apoE in the pathophysiology of AD. These include the discovery of the relationship between the epsilon 4 allele and AD, the ability of this protein to form complexes with beta amyloid protein (A beta) in seniles plates, its presence in neurofibrillary tangles and in vessels of AD patients. Another important finding is the differential interaction between the different isoforms of apoE and tau protein. Some of the hypotheses implicate the role of different apoE isoforms on the growth and extension of neurones, perhaps by a receptor mediated pathway. It has been suggested that apoE acts as a pathological chaperone protein, or alternatively that it protects neurons by regulation of the cell membrane and modifying calcium homeostasis. It is clear that apoE genotype determination alone cannot be used for diagnosis of AD. The presence of epsilon 4 allele is only one of several risk factors for the development of the disease. Other factors may also be implicated and are the subject of ongoing research.

Alzheimer Disease↗