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D Grüneklee

Publications and source records attributed to D Grüneklee.

At least 19 recordsLinked to original sources

Bioavailability assessment of the lipophilic benfotiamine as compared to a water-soluble thiamin derivative.

The bioequivalence of thiamin in 2 therapeutically used preparations was tested in 10 healthy young men. Thiamin was orally administered either as lipophilic benfotiamine or as water-soluble thiamin mononitrate. Biokinetic data, measured as area under the curve and maximal concentration in plasma and hemolysate after ingestion, demonstrated a significantly improved bioavailability from the lipophilic derivative despite an ingested dose of only 40% as compared with the water-soluble salt. A superior cellular efficacy of benfotiamine was also concluded from the short-term stimulation of the thiamin-dependent transketolase activity in erythrocytes.

Adult

Proinsulin autoantibodies: association with type I diabetes but not with islet cell antibodies, insulin autoantibodies or HLA-DR type.

Antibodies reacting with proinsulin but not with insulin determinants have been observed recently in Type I diabetes. We describe here that ELISA-determined proinsulin autoantibodies (IgG-PAA) also occur in first-degree relatives of IDDM patients (38/513, 7.4% vs 1.9% in controls, P less than 0.025). In contrast to insulin autoantibodies (IgG-IAA) and islet cell antibodies (ICA) no association with HLA type was found. Furthermore, IgG-PAA occur independently of IgG-IAA and ICA. We conclude that the humoral autoimmune response to proinsulin determinants is under separate genetic control.

Autoantibodies

Prospective analysis of islet cell antibodies in children with type 1 (insulin-dependent) diabetes.

The prevalence of islet cell antibodies in children with Type 1 (insulin-dependent) diabetes was determined in a cohort of 678 children. The natural course of islet cell antibodies was followed in 375 children at 1 year, 252 and 135 children after 2 and 3 years respectively. Islet cell antibodies were determined by indirect immunofluorescence on cryostat sections of human pancreas. At diagnosis of diabetes 85% of the children had detectable islet cell antibodies (mean titre 10.4). After 3 years 62% of the children were still islet cell antibody positive (mean titre 2.9) indicating a greater persistence of islet cell antibodies than described in earlier studies. In this large cohort a significant correlation between islet cell antibody prevalence or persistence and sex, age or HLA-DR type was not observed except for a faster loss of islet cell antibodies in very young boys and in patients lacking HLA-DR types 3 and 4. Complement fixing islet cell antibodies correlated with high titre islet cell antibodies. Greater persistence of islet cell antibodies was seen for cases with high antibody titre and in children with diagnosis of diabetes during the first half of the year.

Adolescent

Prevalence of coeliac disease in diabetic children and adolescents. A multicentre study.

Screening for coeliac disease (CD) with serum antigliadin antibodies (AGA) was performed in 1032 diabetic children and adolescents. In 8 children CD had been diagnosed before study entry. Of the remaining 1024 children, 33 had an elevated AGA titre in the first serum sample. On follow-up an elevated AGA titre was confirmed in only 17 of 31 patients. Nine of the repeatedly positive patients underwent jejunal biopsy, and CD was diagnosed in two asymptomatic patients; both were positive for IgG- and IgA-AGA. Among 10 AGA-positive patients in whom biopsies could not be performed, only 1 showed IgA-AGA and thus carried a high risk for CD. From our results we estimate a prevalence of CD in Swiss and German diabetic children between 1.1% and 1.3%. False-positive AGA titres occurred significantly more often in patients with diabetes duration of less than 1 year. AGA testing reached a specificity of 99% if performed at least 1 year after the onset of diabetes. Children suffering from both diabetes and CD showed a diabetes manifestation at a significantly younger age than non-coeliac patients, whereas CD tended to be diagnosed at a remarkably late age.

Adolescent

Neutralizing antibodies against Coxsackie B viruses in patients with recent onset of type I diabetes.

In a search for Coxsackie B virus-induced, insulin-dependent diabetes mellitus (IDDM) we examined sera from 166 selected patients (age 1-17 years) with recent onset of IDDM for specific neutralizing antibodies. All 166 patients investigated had a clinical history of recent infectious illness. Eighty per cent of the patients had antibodies against at least one Coxsackie B virus type. But even among the children studied with antibody titers higher than 256 only in about 44% could a recent Coxsackie B virus infection be serologically demonstrated by determining specific neutralizing IgM antibodies. This result again strengthens the notion that IDDM includes several different etiologic groups, among others possibly Coxsackie B virus infections.

Adolescent

Age-related association of insulin-dependent diabetes mellitus with BfF1 and the HLA-B18, BfF1 haplotype.

Five hundred and ninety-nine patients with insulin-dependent (Type 1) diabetes mellitus were typed for Bf (factor B) polymorphism, and 318 of them for HLA-A, B and C antigens. Bf and HLA antigen frequencies were compared with those in 536 normal controls. A significant positive association between Type 1 diabetes and the rare factor B variant BfF1 was found (p less than 10(-3)), but this was present only in patients aged under 16 years at onset of the disease (p less than 0.005). There was a strongly positive linkage disequilibrium between BfF1 and HLA-B18 in the diabetic patients. This, too was especially pronounced in the juvenile onset cases, in whom it was significantly stronger than in controls (p less than 10(-3)). The known positive associations between Type 1 diabetes and HLA-B8, -B15 and -Cw3 were confirmed.

Adolescent

[Granulomatous allergic reaction of the delayed type to surfen].

In the last five years, a distinct increase of allergic reactions to surfen, a constituent of various insulin preparations, was observed. The allergic reactions were tuberculoid granulomas of the delayed type (type IV of Gell and Coombs). Intracutaneous tests with surfen or surfen-containing insulin preparations confirmed the diagnosis. Dermal infiltrates and mild erythema developed 24 to 96 hours after the injection of insulin. In some patients a post-inflammatory pigmentation was noted. Histological examination of the lesions and the intracutaneous test sites revealed a granulomatous inflammation without signs of foreign body reaction. At present, the cause of the increased incidence of allergic reactions to surfen remains hypothetical.

Chemical Phenomena

[Glucagon, growth hormone, and cortisol response to insulin-induced hypoglycemia in insulin-dependent diabetics (IDD) without autonomic neuropathy (author's transl)].

Insulin-induced hypoglycemias are a sign of non-sufficient counterregulation, in which different contra-insulinary hormones participate. The aim of the study was to investigate, whether there exists a difference between IDD and non-diabetics regarding secretion of glucagon, cortisol, and growth hormone during an insulin-induced hypoglycemia and further on pointing out, expecially, the importance of glucagon. Insulin-induced hypoglycemias are counterregulated in non-diabetics, not in IDD. The missing glucagon secretion during insulin-induced hypoglycemia in IDD seems to be independent from an autonomic neuropathy. Only after high doses of exogenous glucagon can one see a counterregulating increase of glucose. The STH secretion is similar in non-diabetics and IDD during an insulin-induced hypoglycemia and has evidently only a secondary effect in hypoglycemic counterregulation. The STH secretion may be the expression of a diencephal-triggered stress situation. The cortisol secretion is the same in both groups. The gluconeogenetic effect of cortisol is not sufficient to accomplish a fast compensation of hypoglycemia. This does not exclude long-term effects. When inhibiting the secretion of insulin and different contra-insulinary hormones with somatostatin, one is able to demonstrate that glucagon alone is a sufficiently counterregulatory hormone in insulin-induced hypoglycemias.

Adult

Studies of heart rate oscillations in diabetics at rest.

Variation in electrocardiographic R-R intervals during rest was investigated as a measure of autonomic function and as a diagnostic tool in diabetes. Diabetics (106) of both sexes with different duration of the disease were compared with 116 metabolically healthy control subjects of the same age range. Diabetic retinopathy was diagnosed using fundus photography, and classified in stages O-II. Coefficient of variation (CV) of R-R intervals in controls is age-dependent. The negative correlation between CV and age in diabetics applied only when retinopathy was absent; in diabetics with late complications, CV was significantly lower (p less than 0.0001) than in the healthy or in uncomplicated diabetic state. The CV decreased with increasing severity of retinopathy permitting routine differentiation of progressive stages of retinopathy and peripheral neuropathy.

Adolescent

Psychometric evaluation of performance in diabetes mellitus.

Two-hundred and fourteen diabetics and 343 controls were studied using a psychological test battery (LPSU-KOLN). Out of these samples, 147 pairs matched for age, sex, and level of education were selected. Diabetics were classified as juvenile onset diabetics (JOD, n = 112) and maturity onset diabetics (MOD, n = 35). The performance was evaluated in four dimensions: Factor I: speed of reaction; Factor II: memory-concentration; Factor III: visual perception; and Factor IV: quality of performance. The data were statistically analyzed using a multivariate analysis of variance (MANOVA). The speed of reaction of both types of diabetics was significantly lower than of that of controls. The abilities in memory-concentration tasks were also decreased in diabetics in general, particularly in MOD. The visual perception and the quality of performance of diabetics were not different from their controls.

Adult