Biomedical subjects

W Bachmann

Publications and source records attributed to W Bachmann.

133 records · Page 8Linked to original sources

PubMedDate not supplied

Exercise-induced hypoglycaemia and subcutaneous insulin infusion.

To assess whether exercise-induced hypoglycaemia could be prevented by interruption of insulin infusion (3 h) we studied diabetic patients treated with continuous subcutaneous insulin infusion (CSII). The studies were performed in 7 insulin-dependent diabetics (aged 31.4 +/- 4.8 (mean +/- SD) years, duration of diabetes 16.9 +/- 5.4 years), after an overnight fast and in the afternoon, 4 h after the last pre-meal bolus injection (exercise and control period). Bicycle exercise (45 min at 60% of maximum oxygen consumption) was started 30 min after the insulin infusion was stopped. During exercise there was a more pronounced decline in blood glucose in the afternoon (2.2 +/- 0.3 mmol/l, mean +/- SEM) than in the morning (1.4 +/- 0.4 mmol/l) (p less than 0.01). This corresponded to higher mean levels of free insulin during exercise in the afternoon (20 +/- 4.5 mU/I vs 12.0 +/- 1.0 mU/l, in the morning). Interruption of insulin delivery for 3 h resulted in a moderate increase of blood glucose, a gradual decrease of free insulin, and a moderate increase in free fatty acids and beta-hydroxybutyrate. During exercise in the afternoon 3 diabetics suffered from symptomatic hypoglycaemia (BG less than 2.8 mmol/l). In contrast with most of the other patients they showed no decline of free insulin during exercise. Thus even after interruption of basal rate insulin infusion moderate postprandial exercise may lead to hypoglycaemia if there is relative hyperinsulinism.

Adult↗

PubMedDate not supplied

Binding of biosynthetic human insulin to erythrocytes of normal and insulin-dependent diabetic subjects: comparison with pork and human pancreatic insulin.

Biosynthetic human insulin (BHI) was compared with highly purified human pancreatic and pork insulin with regard to its ability to bind to erythrocytes of normal and insulin-dependent diabetic subjects (type I diabetes). The binding affinity or capacity of erythrocyte from both normal and diabetic subjects were comparable for biosynthetic and pancreatic human insulin. In contrast, binding of pork insulin to erythrocytes was significantly decreased at low insulin concentrations in normal as well as in diabetic subjects due to a reduced receptor affinity. The affinity of the "empty sites" was 5.25 x 10(-8) M-1 with pork insulin in normal subjects and 6.1 x 10(-8) M-1 in diabetic subjects; with both human insulins, the affinities were 6.9 x 10(-8) M-1 in normal subjects and 8.6 x 10(-8) M-1 in diabetic subjects. The number of insulin receptors per erythrocyte was calculated as being 30 in normal subjects and 35 in diabetic patients.

Animals↗

PubMedDate not supplied

Treatment with human insulin (recombinant DNA) in diabetic subjects pretreated with pork or beef insulin: first results of a multicenter study.

In two double-blind studies 66 insulin-dependent diabetic subjects pretreated with pork insulin were changed to human insulin (recombinant DNA) or a purified pork insulin preparation (regular and NPH insulin). Sixty-five patients previously pretreated with beef insulin were transferred, in a randomized, double-blind fashion, to human insulin and purified beef insulin of the same preparations (regular and NPH insulin). Patients' metabolic control, as demonstrated by fasting and 1-h postprandial blood glucose, HbA1c, and daily insulin dosage, over 4 mo was unchanged in our four groups compared with the values before changing insulin preparation. No severe hypoglycemic attacks or skin reactions were reported.

Adult↗

PubMedDate not supplied

Human insulin (recombinant DNA) in the treatment of patients with newly diagnosed insulin-dependent diabetes mellitus (IDDM).

Human insulin (recombinant DNA) was administered subcutaneously to 16 patients with newly diagnosed insulin-dependent diabetes mellitus (IDDM), whereas a control group of 11 patients received highly purified pork insulin (PPI). The control group was only available for the inpatient period, while the HI-treated patients could be observed monthly afterward. For metabolic control, basal and post-prandial blood glucose, plasma C-peptide, and HbA1 were measured. During the outpatient period, blood glucose self-monitoring was also performed. Within 6 days of therapy, blood glucose levels were lowered to normal without any statistical differences between the HI and PPI groups. Mean insulin requirement was 35 U/day in both groups. Plasma C-peptide levels were not different at any time. In the human insulin group, HbA1 values were continuously lowered from the initial 13% to the normal range within 2-3 mo and remained normal after 6 mo of therapy. No allergic reaction and no other side effects could be seen. The results suggest that in the first period of treatment, the metabolic situation of patients with IDDM could be well controlled by human insulin as well as by PPI. Human insulin has been proven to be an effective and safe insulin.

Adolescent↗

PubMedDate not supplied

Efficiency of human insulin (recombinant DNA) in the treatment of diabetic ketoacidosis and severe nonketoacidotic hyperglycemia.

Human insulin (recombinant DNA) was compared with pork insulin in the treatment of diabetic ketoacidosis and severe nonketoacidotic hyperglycemia using a continuous, intravenous, low-dose regimen. Seven patients (age range 48 +/- 26 yr, mean +/- SD) with diabetic ketoacidosis and three (52, 65, and 70 yr) with nonketoacidotic hyperglycemia were studied. In the ketoacidotic group the initial values of blood glucose, pH, and base excess were 808 +/- 353 mg/dl, 7.06 +/- 0.1, and -22.8 +/- 5.9 mmol/L, respectively. The mean initial values of blood glucose and osmolality of the three patients with nonketoacidotic hyperglycemia were 731 +/- 127 mg/dl and 355 +/- 49 mosmol/kg, respectively. Within 24 h insulin therapy led to continuous improvement in blood glucose to 187 +/- 90 (ketoacidotic patients) and 172 +/- 28 mg/dl (nonketoacidotic group) and normalization of pH, base excess, and osmolality. The mean insulin requirement was 84 +/- 45 U/24 h in ketoacidotic and 86 +/- 18 U/24 h in nonketoacidotic patients, respectively. The comparison groups receiving pork insulin did not differ significantly in either clinical or initial and subsequent biochemical data or in insulin requirement.

Adolescent↗

PubMedDate not supplied

Intradermal desensitization with human insulin (recombinant DNA) in a patient with severe allergic skin reaction due to insulin.

This is a case report of a 70-yr-old female patient with a severe allergic skin reaction (necroses) due to insulin injections. Because of insulin dependency, desensitization to insulin was mandatory. For desensitization, a schedule with intradermal injections of increasing insulin concentrations (from 0.02 to 2 U per injection) at time intervals of 3 h was used. With highly purified pork insulin, the concentration limit of 0.04 U was reached in spite of 75 injections. After changing to human insulin (recombinant DNA), a rapid desensitization could be performed at the same concentration. Desensitization resulted not only to human insulin but also to highly purified pork insulin, as shown by intradermal testing 6 mo later.

Aged↗

PubMedDate not supplied

Silicon cast method for quantification of photoablation.

BACKGROUND: Topometry and measurement of photoablation patterns are key questions for keratorefractive photoablation. Ablation rates have been determined previously by either tissue perforation or by micrometry performed on histologic sections. METHODS: A three-dimensional cast of cornea after irradiation was made by using a two-component silicon gel that polymerizes within minutes, thus preserving the corneal topography immediately after photoablation. Polymerization is athermal and nontoxic. The resulting silicon blocks were cut perpendicularly to the anterior surface and measured by calibrated light microscopy. RESULTS: The silicon surface is extremely smooth and the accuracy of the cast is better than 0.25 micron. Reproducibility and long-term stability were demonstrated for casts of photoablated polymethylmethacrylate. Thus, ablation rates and profile, volumetry, and topometry can be determined following laser ablation. The method has been applied for 193-nanometer excimer laser in vitro irradiation of the human cornea. Ablation rates in Bowman's layer and stroma for various radiant energies and distinct pulse numbers were found to be in agreement with published data, and an incubation effect for the first laser pulses could be demonstrated. CONCLUSIONS: The method is nondestructive, accurate, inexpensive, practical, and reduces requirements for laboratory animals.

Animals↗