PubMed Health⌕ Search

Biomedical subjects

O Søvik

Publications and source records attributed to O Søvik.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Non-insulin dependent diabetes in children and adolescents].

Maturity-onset diabetes of the young (MODY) is a clinically and genetically heterogenous disorder characterized by autosomal dominant inheritance with onset usually before 25 years of age, and a primary defect in glucose-stimulated insulin secretion. Genetic analyses have shown that mutations in at least five different genes can cause MODY. These are the genes encoding the glycolytic enzyme glucokinase, three liver-enriched transcription factors, hepatocyte nuclear factor (HNF)-1 alpha, HNF-1 beta and HNF-4 alpha, and the gene encoding the transcription factor, insulin promoter factor-1 (IPF-1). Patients with MODY3 run a considerable risk of developing diabetic eye disease. MODY2, related to glucokinase deficiency, is a relatively benign disorder which does not usually require insulin. Experiences with the three other MODY forms have so far been restricted to very few families. We present the first Norwegian family with MODY2. Furthermore, a previously published Norwegian family is shown to be MODY3. Subjects who fulfil the criteria of MODY can, by genetic testing, gain information important for prognosis and perhaps also for therapy.

Adolescent↗
PubMed1998

Insulin management and metabolic control of type 1 diabetes mellitus in childhood and adolescence in 18 countries. Hvidøre Study Group on Childhood Diabetes.

Insulin regimens and metabolic control in children and adolescents with Type 1 diabetes mellitus were evaluated in a cross-sectional, non-population-based investigation, involving 22 paediatric departments, from 18 countries in Europe, Japan, and North America. Blood samples and information were collected from 2873 children from March to August 1995. HbA1c was determined once and analysed centrally (normal range 4.4-6.3%, mean 5.4%). Year of birth, sex, duration of diabetes, height, body weight, number of daily insulin injections, types and doses of insulin were recorded. Average HbA1c in children under 11 years was 8.3 +/- 1.3% (mean +/- SD) compared with 8.9 +/- 1.8% in those aged 12-18 years. The average insulin dose per kg body weight was almost constant (0.65 U kg(-1) 24 h(-1)) in children aged 2-9 years for both sexes, but there was a sharp increase during the pubertal years, particularly in girls. The increase in BMI of children with diabetes was much faster during adolescence compared to healthy children, especially in females. Sixty per cent of the children (n = 1707) used two daily insulin injections while 37% (n = 1071) used three or more. Of those on two or three injections daily, 37% used pre-mixed insulins, either alone or in combination with short- and intermediate-acting insulin. Pre-adolescent children on pre-mixed insulin showed similar HbA1c levels to those on a combination of short- and long-acting insulins, whereas in adolescents significantly better HbA1c values were achieved with individual combinations. Very young children were treated with a higher proportion of long-acting insulin. Among adolescent boys, lower HbA1c was related to use of more short-acting insulin. This association was not found in girls. We conclude that numerous insulin injection regimens are currently used in paediatric diabetes centres around the world, with an increasing tendency towards intensive diabetes management, particularly in older adolescents. Nevertheless, the goal of near normoglycaemia is achieved in only a few.

Adolescent↗
PubMed1998

Generalized peroxisomal disorder in male twins: fatty acid composition of serum lipids and response to n-3 fatty acids.

Male, identical twins presented with hypotonia, hypoglycaemia, dysmorphic facies, feeding problems, discoloured stools, hepatomegaly, and nephrolithiasis. Elevated blood levels of very long-chain fatty acids and bile acids suggested a peroxisomal disorder. Plasmalogen biosynthesis in cultured fibroblasts was reduced. Morphologically distinct peroxisomes were undetectable in liver. Twin 1 suffered from nephrocalcinosis and severe infection, and died at 18 months of age. Twin 2 was blind and physically severely retarded with epilepsy, but survived up to the age of 5 years. Studies of the fatty acid composition of serum lipids showed barely detectable values of eicosapentaenoic (EPA) and docosahexaenoic acid (DHA). During long-term treatment with these n-3 fatty acids, started at age 10 months, the fatty acid profile of the serum lipids was improved or normalized. Since n-3 fatty acids are essential elements in normal development, notably of the nervous system, we suggest that treatment with EPA and DHA should be started as early as possible in general peroxisomal disorders.

Diseases in Twins↗
PubMed1998

A missense mutation, Val62Ala, in the glucokinase gene in a Norwegian family with maturity-onset diabetes of the young.

Maturity-onset diabetes of the young (MODY) is a form of diabetes mellitus characterized by autosomal dominant inheritance, onset usually before 25 y of age and a primary defect in glucose-stimulated insulin secretion. It is a heterogeneous disorder both with respect to aetiology and clinical features. Mutations in the genes encoding the glycolytic enzyme glucokinase, the liver-enriched transcription factors, hepatocyte nuclear factor-1alpha (HNF-1alpha), HNF-1beta and HNF-4alpha, and the transcription factor, insulin promoter factor-1 (IPF-1) have all been associated with MODY. Here, we report a family, Norway-2 (N2), characterized by the presence of a mild, complication-free form of diabetes with autosomal dominant inheritance. Sequencing of the glucokinase gene in the proband revealed a T-to-C mutation in codon 62 which resulted in a valine-to-alanine substitution, designated Va162Ala (V62A). The V62A mutation, which has not been previously reported, cosegregated with diabetes in the N2 family. The results presented here indicate that the glucokinase form of MODY occurs in Norway. Moreover, screening the glucokinase gene for mutations in other families with clinical features similar to those of the N2 family could lead to improved treatment for patients with this form of diabetes.

Adult↗
PubMed1997

[Incidence and content of written guidelines for "do not resuscitate" orders. Survey at six different somatic hospitals in Oslo].

This paper presents the incidence of, and contents of guidelines for do-not-resuscitate orders (DNR orders) in somatic hospital departments in Oslo. Only five out of 14 departments had written guidelines. There was a wide range of contents concerning illness criteria, decision-making responsibility and patient and family participation in the decision-making process. We find that there is a need for written guidelines for the use of DNR orders and present a template for the appropriate use of such orders. The proper use of DNR orders will prevent futile cardiopulmonary resuscitation and hopefully bring about a discussion on the ethical aspects of treatment decisions in hospital departments.

Cardiopulmonary Resuscitation↗
PubMed1997

Medium chain acyl-CoA dehydrogenase deficiency and fatal valproate toxicity.

A boy with delayed psychomotor development, attention deficit disorder, and therapy-resistant epilepsy was treated with valproate. The patient died of liver failure after 4 months of valproate treatment. Postmortem investigation of cultured fibroblasts suggested medium chain acyl-CoA dehydrogenase deficiency, an unexpected finding since the boy had not presented typical manifestations of this disease. Because medium chain acyl-CoA dehydrogenase is an important enzyme in the beta-oxidation of fatty acids, our patient probably had a genetically reduced tolerance to valproate. This drug should be omitted in the treatment of seizures in patients with possible medium chain acyl-CoA dehydrogenase deficiency.

Acyl-CoA Dehydrogenase↗
PubMed1997

HLA-encoded genetic predisposition in IDDM: DR4 subtypes may be associated with different degrees of protection.

Recent studies have shown that the risk conferred by the high-risk DQA1*03-DQB1*0302 (DQ8) haplotype is modified by the DRB1*04 allele that is also carried by this haplotype. However, many of these studies suffer from lack of sufficient numbers of DQ-matched control subjects, which are necessary because there is a strong linkage disequilibrium between genes in the HLA complex. In the present study, using a large material of IDDM patients and DQ-matched control subjects, we have addressed the contribution of DR4 subtypes to IDDM susceptibility. Our data, together with recent data from others, clearly demonstrate that some DR4-DQ8 haplotypes are associated with disease susceptibility, while others are associated with protection, depending on the DRB1*04 allele carried by the same haplotype. In particular, our data demonstrate that DRB1*0401 confers a higher risk than DRB1*0404. Based on combined available data on the genetic susceptibility encoded by various DR4-DQ8 haplotypes and the amino acid composition of the involved DRbeta*04 chains as well as the ligand motifs for these DR4 subtypes, we have developed a unifying hypothesis explaining the different risks associated with different DR4-DQ8 haplotypes. We suggest that disease susceptibility is mainly conferred by DQ8 while DR4 subtypes confer different degrees of protection. Some DR4 subtypes (i.e., DRB1*0405, 0402, and 0401) confer little or no protection, while others (i.e., DRB1*0404, 0403, and 0406) cause an increasing degree of protection, possibly by binding a common protective peptide. Features of a protective peptide that fit such a model are briefly discussed.

Adolescent↗
PubMed1997

No independent associations of LMP2 and LMP7 polymorphisms with susceptibility to develop IDDM.

Results from a recent study suggested that polymorphisms within the HLA class II genes LMP2 and LMP7 were associated with the susceptibility for developing IDDM, and that this association could not be explained by linkage disequilibrium to HLA-DR or -DQ genes. We typed 285 IDDM patients and 337 HLA-DRB1-DQA1-DQB1 genotypically matched control subjects from an ethnically homogeneous population for both the G/T polymorphism in intron 6 of the LMP7 gene and the Arg-His polymorphism in the LMP2 gene. In addition, we typed IDDM families in which at least one parent was homozygous for a DRB1-DQA1-DQB1 haplotype and performed a transmission/disequilibrium test of these LMP polymorphisms. Our data suggest that none of these LMP2 or LMP7 polymorphisms are independently associated with IDDM susceptibility, in contrast to what has been previously reported by others. Further, our results suggest that one partial explanation for the previously reported independent association between IDDM and these LMP polymorphisms may have been that patients and control subjects were not matched for DRB1*04 subtypes. Our results emphasize the need for a complete matching for DRB1, DQA1, and DQB1 alleles between patients and control subjects when attempting to detect independent effects of other polymorphisms in the HLA complex on IDDM susceptibility or protection.

Cysteine Endopeptidases↗
PubMed1996

Mutations in the testis/liver isoform of the phosphorylase kinase gamma subunit (PHKG2) cause autosomal liver glycogenosis in the gsd rat and in humans.

Heritable deficiency of phosphorylase kinase (Phk), a regulatory enzyme of glycogen metabolism, is responsible for 25% of all cases of glycogen storage disease and occurs with a frequency of -1 in 100,000 births. It is genetically and clinically heterogeneous, occurring in X-linked and autosomal-recessive forms and exhibiting various patterns of principally affected tissues (liver only, muscle only, liver and muscle, liver and kidney, heart only). This heterogeneity is thought to reflect the enzyme's structural complexity [subunit composition, (alpha beta gamma delta)4] and isoform diversity. Two isoforms encoded by separate genes are known for the subunits alpha (muscle [alpha M] and liver [alpha L isoforms) and gamma (muscle [gamma M] and testis [gamma T] isoforms), whereas only one gene appears to exist for the subunit beta. The subunit delta is calmodulin; identical calmodulins are expressed from three different human genes. Additional isoform diversity arises by differential mRNA splicing of the alpha M, alpha L and beta subunits. Mutations responsible for the various forms of Phk deficiency are sought in those subunit/isoform genes with a matching chromosomal location and tissue-specificity of expression. We report here that autosomal liver-specific Phk deficiency is associated with mutations in the gene encoding the testis/liver isoform of the catalytic gamma subunit (PHKG2). We found homozygous PHKG2 mutations in three human patients of consanguineous parentage and in the gsd (glycogen storage disease) rat strain, which is thus identified as an animal model for the human disorder. One human mutation is a single base-pair insertion in codon 89 that causes a frameshift and premature chain termination. The three other mutations result in non-conservative replacements of amino acid residues (V106E, G189E, D215N) that are highly conserved within the catalytic core regions of all protein kinases. These are the first mutations to be reported for an autosomal form of Phk deficiency. The findings suggest that the PHKG2 gene product is the predominant isoform of the catalytic gamma subunit of Phk not only in testis but also in liver, erythrocytes and, possibly, other non-muscle tissues.

Adolescent↗
PubMed1996

Studies of insulin resistance in congenital generalized lipodystrophy.

Two well-characterized patients with congenital, generalized lipodystrophy have been studied by the euglycaemic hyperinsulinaemic clamp technique in combination with indirect calorimetry. Furthermore, glycogen synthase in muscle biopsies was studied in one patient with regard to enzyme activity, immunoreactive protein and mRNA levels. The patients had fasting hyperinsulinaemia, and the rate of total glucose disposal was severely impaired, primarily due to a decreased non-oxidative glucose metabolism. In the patient studied with muscle biopsy, the expected activation of glycogen synthase by insulin did not occur. In both patients there was severely increased hepatic glucose output in the basal state, suggesting a failure of insulin to suppress hepatic gluconeogenesis. During insulin infusion a substantially elevated rate of lipid oxidation remained in the patients, in contrast to the almost completely suppressed lipid oxidation in the controls. It is concluded that patients with congenital generalized lipodystrophy may present severe insulin resistance with regard to hepatic glucose production as well as muscle glycogen synthesis and lipid oxidation. The results suggest a postreceptor defect in the action of insulin in congenital generalized lipodystrophy. The further localization of such a defect is hampered by the still incomplete understanding of the pathways that link insulin-stimulated tyrosine phosphorylation to the ultimate action of insulin upon target cells.

Calorimetry, Indirect↗
PubMed1995

[Familial hypercholesterolemia in children. A management program. Procedures for diagnosis and treatment in our pediatric departments].

A Norwegian programme for treatment and selective screening of familial hypercholesterolaemia has been developed which takes into account family history and levels of hypercholesterolaemia. The programme includes recommendations on when and whom to screen for familial hypercholesterolaemia. With regard to treatment, special emphasis is placed on diet. The working group suggests that small lipid clinics with a dietitian should be established in some paediatric departments.

Child↗
PubMed1995

Dead in bed syndrome in young diabetic patients in Norway.

The incidence of unexplained deaths ('dead in bed syndrome') in Norwegian diabetic patients under the age of 40 was investigated during the period 1981-1990. During this 10-year period there were 240 deaths of all causes in the age group 0-39 years. Sixteen of these cases fulfilled the following criteria of the 'dead in bed syndrome': (1) patient found dead in an undisturbed bed; (2) patient observed to be in good health condition the day before; (3) no clinical evidence of late complications (except background retinopathy in two cases). Of the 16 cases ascertained, 10 were males and 6 females. The age range was 7-35 years, and the duration of diabetes varied between a few months and 26 years. Autopsy, performed in 13 cases, did not reveal any cause of death. Nine patients had been using insulin regimens with multiple daily doses. Twelve patients were reported as having had frequent episodes of hypoglycaemia, with nocturnal episodes in 10 cases. There was apparently an increasing incidence of unexplained deaths during the study period, with 12 of 16 cases occurring in the years 1988 to 1990.

Adolescent↗