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Biomedical subjects

G Steinbach

Publications and source records attributed to G Steinbach.

At least 109 records · Page 6Linked to original sources
PubMed1987

The effect of artificial sweetener on insulin secretion. 1. The effect of acesulfame K on insulin secretion in the rat (studies in vivo).

Acesulfame K is an artificial sweetener which has been used in the food industry for some years. As yet no metabolic effects have been reported. It was reported that the sweetener can induce a cephalic phase of insulin secretion. To analyse the mechanism of this phenomenon, we studied the effect of Acesulfame K on insulin secretion in vivo. Male Wistar rats, weighing 250-300 g were fasted overnight and anaesthetized with phenobarbital. A silicon catheter was inserted into the right cervical vein for injection of test substances and for obtaining blood samples. In some experiments, another catheter was inserted into the left cervical vein for continuous infusion. Blood samples were drawn at 0, 5, 10, 15, 30 and 60 min after injection, and at -10, 0, 10, 20, 30, 40, 60, 80, 100 and 120 min after the infusion started. Injection of Acesulfame K (150 mg/kg body weight) increased the plasma insulin concentration at 5 min from 27.3 +/- 3.0 microU/ml to 58.6 +/- 4.2 microU/ml without any significant change in the blood glucose. Infusion of Acesulfame K (20 mg/kg body weight/min) for one hour maintained the insulin concentration at a high level (about 85-100 microU/ml) during this period, and at the same time blood glucose was gradually reduced from 103.0 +/- 7.3 to 72.0 +/- 7.2 mg/dl. When using different amounts of Acesulfame K, the insulin secretion was stimulated in a dose-dependent fashion. The effect of Acesulfame K on insulin secretion was similar to that observed by injecting or infusing the same doses of glucose (150 mg/kg) body weight for injection and 20 mg/kg body weight/min for infusion), except that no hyperglycemia was observed with Acesulfame K.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

The effect of artificial sweetener on insulin secretion. II. Stimulation of insulin release from isolated rat islets by Acesulfame K (in vitro experiments).

The effect of the artificial sweetener Acesulfame K on insulin release in vitro was investigated. Pancreatic islets were obtained from Male Wistar rats. Acesulfame K produced a significant increase in insulin release from incubated islets. This effect was dose- and glucose-dependent. When islets were incubated with different amounts of Acesulfame K (2.5, 7.5 and 15 mM) and 15 mM glucose in the media for one hour, insulin concentrations were 140.2 +/- 21.1, 246.7 +/- 32.4 and 313.9 +/- 37.7 microU/ml, respectively. When 15 mM Acesulfame K was added to a media containing 0, 2.5, 5, 10 and 15 mM glucose, insulin release from incubated islets after 60 min were 25.6 +/- 6.4, 65.4 +/- 12.1, 109.0 +/- 10.0, 229.6 +/- 28.0 and 313.9 +/- 37.7 microU/ml. Incubating islets in the media containing arginine or acetylcholine increased insulin release significantly. However, when Acesulfame K was added to the media containing either arginine or acetylcholine, no further potentiating effect could be detected. The effect of Acesulfame K on insulin secretion was decreased by noradrenaline. However, the addition of naloxone, atropine and propranolol had no significant effect. Somatostatin inhibited insulin release from isolated pancreatic islets, but did not antagonize the action of Acesulfame K. When 2.5 mM Acesulfame K was added to a medium containing somatostatin, the inhibitory effect of somatostatin was totally neutralized. In a perifusion system, Acesulfame K stimulated both phases of insulin secretion. In conclusion, Acesulfame K acts directly on the pancreatic islets and potentiates glucose-induced insulin release.

Animals↗
PubMed1987

[Vitamin E requirement of chicks and young hens].

In 4 experiments young chickens of the species White Leghorn received semisynthetic rations with a vitamin E content less than 1 mg/kg basal ration. Sunflower oil heated with FeCl3 supplement was used as a factor increasing requirement. Feed intake, live weight gain and feed expenditure with semisynthetic rations without oil supplements did not depend on vitamin E supplements. After the feeding of rations without vitamin E animal losses were higher. The losses were normalized by 1 mg vitamin E supplement per kg feed. Rations containing sunflower oil without vitamin E supplementation resulted in encephalomalacia of the young chickens. Vitamin deficiency increased triiodine thyronine content in the blood plasma. Antibody formation after the application of human gamma globulin did not depend on the vitamin E supply studied. A vitamin E requirement of young chickens and young hens of the laying species of less than 1 mg/kg mixed feed is derived from the results.

Animal Feed↗
PubMed1986

[Vitamin E requirements of laying hens].

In 5 experiments with 1,296 laying hybrids at the age of 22-73 weeks producing eggs for consumption a varied supplementation of between 0 and 20 mg vitamin E per kg of a semisynthetic ration was tested. The vitamin E content of the basal ration was less than 1 mg per kg feed. The quotas of selenium and unsaturated fatty acids in the feed were taken into consideration. Vitamin E and Se supplements did not influence, feed intake, laying, performance, feed efficiency/100 g egg development of body weight and mortality. The supplementation of 14% vitamin-E-free sunflower oil caused a significant decrease of the laying performance by 15%. There was no relation between the humoral immune reaction and vitamin E supply. The peroxide value of the abdominal fat and the activities of the creatine phosphokinase, the aspartate and alanine amino transferase in the blood serum were not directionally changed by the vitamin E, Se and oil supplements. There were no significant relations between the vitamin E content of the feed and that of the yolk and the yolk sac of the chicken. A vitamin E requirement of less than 1 mg and a requirement norm, including a safety margin, of 5 mg per kg feed was derived from the results for laying hens for egg production. A supplement of synthetic vitamin E to laying hen feed is thus not necessary.

Animal Feed↗
PubMed1986

Fetal supraventricular tachycardia refractory to digoxin cardioversion. A case report.

Fetal cardiac arrhythmias are being diagnosed with increased frequency through ultrasonography and electronic fetal heart rate monitoring. Although many of them are benign, some, particularly supraventricular fetal tachycardia, have been associated with a poor outcome. Fetal hydrops and other evidence of fetal cardiac failure resulting from the elevated heart rate have been reported on. Although several modes of treatment have been described, the mainstay of cardioversion in utero continues to be digoxin. This case report demonstrates the need for prompt delivery when in utero cardioversion fails.

Administration, Oral↗
PubMed1985

[Vitamin A requirements of growing swine. 3. Effect of vitamin A supply on the state of health of piglets and fattening swine].

Diseases and losses were registered in dependence on vitamin A supply with 2,035 pigs (6.5-114 kg live weight). The histologic examinations comprised various organs of 72 animals. The content of the main protein fractions as well as antibody titre after supplementing antigenes were determined in the serum of 104 animals. The feeding of a vitamin-A- and carotinefree casein-starch-respectively a Vitamin-A-free cereal-soybeanmeal-diet led to deficiency symptoms after 7-8 respectively 16-19 weeks of experiment particularly in the shape of nervous disturbances and voice affectations. Histologically a hyperplasia and a metaplasia of the epithelium of the big ducts in the salivory gland could be proved. The repletion of a part of the avitaminotic animals by means of oral (500 I.U./kg feed) and parenteral (500,000 to 1,000,000 I.U. i.m.) vitamin A administration is proof of a lack of vitamin A. Vitamin A and provitamin dosage did not influence diseases and losses with the exception of the occurrence of deficiency symptoms. The protein content of the serum as well as that of the globulin fractions alpha, beta, gamma did not change, the albumin content was lower in the groups without vitamin A (p greater than 0.05). Antibody titre against the lipopolysaccharide of salmonella dublin and human gamma globulin were diminished in piglets and fattening pigs fed vitamin A free (p less than 0.05). Taking the criterion of animal health, a vitamin A requirement higher than for growth (250 I.U./kg feed) cannot be derived.

Age Factors↗
PubMed1984

[What attitude to dying do we have today?].

Deficient care and unfounded loneliness increasingly form the fate of dying patients. A change under the aspects of socialist norms is the task of the whole society.

Attitude to Death↗
PubMed1984

[Helping to die--helping to live in the boundary between life and death].

Help for the dying patient is a matter of the physician's duty in the sense of the help for life in a border-line situation of human life. Even if the activity of the physician is no more determined by the thought of the preservation of life, the aims in the care for dying patients are on principle to be compared with those in the care for other patients and contain essential principles of the activity of the physician: somatic area (treatment and care) psycho-social area (aid, care and communication). While the hospital in the somatic field has prerequisites for a careful treatment and care, the domestic milieu has advantages in the psycho-social area. It is recommended a flexible and individually adapted performance of the care of dying patients in the hospital and the domestic milieu.

Attitude to Death↗