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Biomedical subjects

J Ostman

Publications and source records attributed to J Ostman.

At least 73 records · Page 4Linked to original sources

Nerve fibre studies in skin biopsies in peripheral neuropathies. I. Immunohistochemical analysis of neuropeptides in diabetes mellitus.

Standardised skin biopsies followed by immunohistochemical examination for the presence of terminal nerve fibres reacting for neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) were evaluated. Healthy subjects regularly displayed free nerve endings of both fibre types in the papillary and reticular dermis. Both fibre types were present close to blood vessels, while CGRP immunoreactive fibres were more often encountered near sweat gland acini compared to SP fibres. Diabetes mellitus complicated by polyneuropathy was accompanied by marked reduction of SP and CGRP reactive fibres in the dermis layers. Five type I diabetes patients without clinical or neurophysiological evidence of polyneuropathy also had reduced density of both fibre types, being significant for CGRP fibres when compared with controls. Skin biopsy with immunohistochemical staining for neuropeptides may represent a sensitive tool in evaluation of patients with peripheral neuropathies.

Adult↗

Fifteen years' experience with pancreas transplantation with pancreaticoenterostomy.

We report on 92 pancreas transplantations with exocrine diversion by pancreaticoenterostomy. All recipients suffered from long-term type I (insulin-dependent) diabetes. In most transplantations, cadaveric segmental grafts were used (n = 89). In a few patients, segmental grafts from related donors were used (n = 3), and in a few other patients, whole-organ cadaveric grafts were used (n = 4). There were 9 retransplantations. Most pancreas transplantations were performed in uremic diabetic patients in combination with a kidney transplantation (n = 58). In a few patients the pancreas transplantation was performed after a kidney transplantation (n = 6). The remaining transplantations were in nonuremic diabetic patients who received only a pancreas (n = 25). Over the years, the results have improved considerably; in the 1986-1987 series the overall 1-yr patient survival (ps) and graft survival (gs) rates were 97 and 56%, respectively. The best results were achieved with the combined procedure (ps 100%, gs 77%); with pancreas only, the figures were inferior (ps 92%, gs 34%). Several factors explain the improved results. The incidence of graft thrombosis has been reduced by the use of anticoagulation, and posttransplantation pancreatitis has been reduced by avoiding ischemic injury to the graft. Cyclosporin has helped reduce the incidence of graft rejection, and monitoring of the exteriorized pancreatic juice has helped in the diagnosis of rejection.

Diabetes Mellitus, Type 1↗

Effects of pancreas transplantation on metabolic and hormonal profiles in IDDM patients.

The diurnal patterns of relevant metabolites and hormones in five pancreas-kidney-transplanted patients (aged 36 +/- 2 yr, mean +/- SD) with insulin-dependent diabetes mellitus (IDDM) were compared with those in five kidney-transplanted nondiabetic patients (aged 28 +/- 2 yr). The groups were matched for body mass and current dose and type of immunosuppressive treatment. The serum creatinine levels did not differ between the two study groups, but the serum urea level in the nondiabetic patients was slightly but significantly higher than in the diabetic patients. In the pancreas-kidney-transplanted group the investigation was performed 8-47 mo posttransplantation; in the kidney-transplanted nondiabetic patients, 12-18 mo posttransplantation. The mean 24-h levels and rhythms of blood glucose, free fatty acid, 3-hydroxybutyrate, and alanine did not differ between the groups. The mean 24-h levels of blood lactate and glycerol were moderately but significantly higher in the pancreas-kidney-transplanted diabetic patients. At fasting, the level of serum immunoreactive insulin was more than twice as high in the pancreas-kidney-transplanted patients, whereas the plasma C-peptide levels did not differ significantly between the two groups. The meal-induced increases in serum insulin as well as in the plasma C-peptide levels were more marked in the pancreas-kidney-transplanted patients. The findings suggest that the hyperinsulinemia in these patients was due to both the systemic delivery of insulin and an increase in insulin resistance, the latter being particularly apparent in the postprandial phase.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Hydroxybutyric Acid↗

Adrenoceptor occupancy in isolated human fat cells and its relationship with lipolysis rate.

The relationship between lipolysis and adrenoceptor occupancy was determined in isolated human fat cells, which possess both lipolytic beta-adrenoceptors and antilipolytic alpha 2-adrenoceptors. The beta-adrenoceptor agonist, isoprenaline, and the alpha 2-adrenoceptor agonist, clonidine, had lower affinities to compete with antagonist radioligands (Ki) than to affect the rate of lipolysis (Ka). At 1 min of incubation human fat cells bound isoprenaline and clonidine with high affinity to beta- and alpha 2-adrenoceptors, respectively, but this high-affinity binding rapidly converted to a low-affinity state. The relationship between lipolysis and adrenoceptor occupancy was also assessed after long-lasting receptor inactivation. The inactivation of a small receptor fraction shifted the dose-response curves for isoprenaline and clonidine to the right but did not alter the maximum effect of the agonists (responsiveness). These results suggest that alpha 2- and beta-adrenoceptors are coupled to lipolysis according to similar models. There is a non-linear relationship between receptor and effector for both receptors, which can be explained by the co-existence of spare receptors and a transient high-affinity state of the receptors for agonists.

Adipose Tissue↗

Effect of felodipine in refractory hypertension.

Felodipine (Plendil), a new drug, has been used in the treatment of five patients with refractory essential hypertension (WHO II-III). Their mean blood pressure at the last outpatient visit before the study was opened was 195 +/- 25/129 +/- 21 mmHg (mean +/- s.d.) (range 175-235/110-165 mmHg), despite treatment with combinations of diuretics, beta-blockers and vasodilators, including minoxidil and captopril. Felodipin is a dihydropyridine derivative, a calcium antagonist that exerts a relaxant effect on resistance vessels. The first period of the study consisted of a 5-day stay in hospital followed by 3 months during which observations were carried out at the Outpatients' Department. After the first days in hospital felodipine therapy was introduced at a dose of 25 mg three times daily, given together with diuretics, beta-blockers and, in one case, captopril. At 8.00 immediately before the first dose was given, the blood pressure was 178 +/- 19/118 +/- 19 mmHg (mean +/- s.d.); 2 h later it was 144 +/- 18/85 +/- 4 mmHg, at which level it remained throughout the rest of the study. At the 3-month follow-up the mean pressure (recorded at the Outpatients' Department) was 138 +/- 20/89 +/- 14 mmHg. Side-effects included headache, flushing, palpitations and ankle oedema (in two patients during the second part of the study); they were of a mild to moderate degree and did not interfere with the treatment. There was no evidence of general fluid retention, and the body weight remained constant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Are effects of antihypertensive treatment on lipoproteins merely "side-effects"? A comparison of prazosin and metoprolol.

Thirty-seven patients with a supine systolic blood pressure greater than 160 and/or a diastolic blood pressure greater than 95 mmHg were enrolled in the study and treated for 6 months with prazosin and 6 months with metoprolol (in random order). Neither the systolic nor the diastolic blood pressures differed after the two types of treatment (median difference 0/0 mmHg). The mean and median differences in serum cholesterol, however, were 0.4 and 0.3 mmol/l respectively, which were 9 and 5% of the pretreatment values. The corresponding differences in the atherogenic index (in which cholesterol in high density lipoproteins is integrated) were 10 and 8% of the pretreatment values. This difference in the metabolic response to the two drugs at the same blood pressure level is most probably of importance in the long-term prevention of ischaemic heart disease, for which high levels of serum cholesterol and atherogenic index are major risk factors.

Clinical Trials as Topic↗

Residual insulin production, glycaemic control and prevalence of microvascular lesions and polyneuropathy in long-term type 1 (insulin-dependent) diabetes mellitus.

The aim of the present study was to evaluate the role of residual insulin production in long-term Type 1 (insulin-dependent) diabetes mellitus. Ninety-seven patients with a disease duration of 9-16 years and onset before the age of 30 years were studied. C-peptide excretion in 24-h urine samples was measured as an indicator of residual insulin production. Thirty-five patients (36%) excreted C-peptide (greater than or equal to 0.2 nmol); as many as possible of them were carefully matched with a non-excretor patient with regard to age at onset of diabetes and disease duration. Twenty-nine pairs were obtained, and 22 of them agreed to participate in further investigations of glycaemic control and microangiopathic lesions. The patients who excreted C-peptide had significantly lower HbA1c than the non-excretor group, 6.9 +/- 0.3% vs 7.9 +/- 0.3%, (p less than 0.025). Moderate-to-advanced background retinopathy was found in 2 patients in the excretor group and in 7 patients in the non-excretor group. Microalbuminuria [ratio of albumin: creatinine (mg/l:mmol/l) greater than or equal to 5] was found in 1 and in 5 patients, respectively, while proteinuria [ratio of protein: creatinine (mg/l:mmol/l X 10) greater than or equal to 136] was found in 0 and in 4 patients, respectively. Microalbuminuria and/or proteinuria was found in 7 of the non-excretor group as compared to 1 in the excretor group (p = 0.046).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Improved results in pancreatic transplantation by avoidance of nonimmunological graft failures.

Twenty eight consecutive combined renal and pancreatic transplantations with enteric exocrine diversion were performed between June 1984 and May 1986. The one-year actuarial patient survival and renal and pancreatic graft survival were 90%, 67%, and 69%, respectively. Nineteen pancreatic grafts and eighteen renal grafts are currently functioning at 1-24 months. Of the pancreatic graft losses only 2 were attributable to nonimmunological complications. No pancreatic graft was lost due to pancreaticoenteric leakage or vascular thrombosis. This was achieved by reducing the cold ischemia time and by adopting an aggressive anticoagulant policy. In all patients with functioning grafts the fasting blood glucose, glycosylated hemoglobin level, and oral glucose tolerance test were normal. The intravenous glucose tolerance test was normal in most of the patients but subnormal in some.

Adult↗

Serum lipid and lipoprotein levels in long-term insulin-dependent diabetes mellitus. Relation to residual insulin secretion, microvascular lesions and environmental factors.

The aim of the present study concerning patients with long-term insulin-dependent diabetes mellitus was to determine whether the serum lipid and lipoprotein concentrations differ in subjects with and without residual insulin secretion. We also investigated whether factors such as sex, smoking, physical activity and microvascular lesions were associated with particular lipoprotein profiles. C-peptide excretion (greater than or equal to 0.2 nmol) in 24-hour urine samples was used as an indicator of residual insulin secretion. Twenty-two pairs of patients with and without residual insulin secretion matched for age at onset and disease duration were participating in the investigations of glycaemic control and microvascular lesions. The HbA1c was significantly lower in C-peptide excretors than in the non-excretors (6.9 +/- 0.3 vs. 7.9 +/- 0.3%, p less than 0.025). The lipids and lipoprotein fractions were all within normal limits. The HDL2/3 ratio was significantly higher in C-peptide excretors than in non-excretors (1.72 +/- 0.28 vs. 1.10 +/- 0.09, p less than 0.05). Multiple regression analysis showed that factors, such as physical activity, body mass index and glycaemic control could explain more of the variation in the different lipid and lipoprotein fractions than residual C-peptide excretion alone. The only fraction correlating with C-peptide excretion was HDL3 cholesterol. It is concluded that minute residual insulin secretion per se is of minor importance for the regulation of lipids and lipoproteins. Glucose control and residual insulin secretion together with environmental factors seem to be of great importance for the regulation of the lipid and lipoprotein levels in insulin-dependent diabetes mellitus.

Alcohol Drinking↗