Effect of phototherapy on erythrocyte membrane proteins of full-term and premature human newborn infants

Erythrocyte membrane proteins of premature and full-term newborn infants were analyzed by sodium dodecyl sulfatepolyacrylamide gel disc electrophoresis before and after phototherapy for about 21 hours at the irradiation energy of 7.3 x 10(3) erg/cm2/sec. There were no qualitative and quantitative differences in the pattern of membrane proteins before and after phototherapy in these infants.

HLA-DR antigens in pemphigus among Japanese

The frequency of HLA-DR4 was significantly increased at P less than 0.02 in 37 unrelated pemphigus patients (62.2%), when compared with unrelated 73 healthy controls (30.1%). This antigen was more frequently found in pemphigus foliaceus (70.6%) than pemphigus vulgaris (55.8%).

The effect of rectal administration of insulin on the short-term treatment of alloxan-diabetic dogs

Six alloxan-diabetic dogs with fasting plasma glucose levels above 200 mg/100 mL were treated with rectal administration of insulin suppositories twice a day for 6--9 days. The effectiveness was compared with that of subcutaneous insulin injections. In three diabetic dogs with fasting plasma glucose levels below 300 mg/100 mL, both insulin suppository at a dose of 20 U (2.3 U/kg) and subcutaneous insulin at a dose of 0.2 U/kg showed a similar effect in reducing fasting glucose levels and daily urinary glucose amounts. In dogs with higher fasting glucose levels, 0.5 U of subcutaneous insulin/kg is less effective in reducing fasting glucose than 50 U (5.2 U/kg) suppositories, in spite of the same effects on daily urinary glucose output. Postprandial glucose responses were significantly lessened with rectal administration of insulin suppositories. The integrated area of increase in peripheral insulin concentration after subcutaneous infection of 0.2 or 0.5 U insulin/kg was significantly greater than that after rectal administration of an insulin suppository (2.3 or 5.2 U/kg, respectively). These results indicate that diabetes could be controlled by the daily rectal administration of an insulin suppository instead of the conventional subcutaneous injection.

Perfect normalization of excessive glucagon responses to intravenous arginine in human diabetes mellitus with the artificial beta-cell

To elucidate the precise significance of pancreatic A-cell hypersecretion in the pathogenesis of diabetes mellitus, the change in the immunoreactive glucagon (IRG) response to intravenous arginine was studied in both nonobese, hypoinsulinemic non-insulin-dependent (NIDDM) and insulin-dependent diabetic (IDDM) subjects whose blood glucose responses and plasma immunoreactive insulin (IRI) simulated those of healthy subjects with the aid of the artificial beta-cell system that we originally developed. In both five NIDDM and five IDDM subjects, blood glucose responses and plasma IRI after arginine challenges were made equivalent to those seen in healthy subjects by infusing insulin in response to blood glucose, revealing that previously exaggerated IRG responses were made completely similar to the responses in healthy subjects. In summary, these results clearly demonstrate that the exaggerated response of A-cell secretion against arginine challenges in insulin-deficient diabetics is secondary to insulin lack, and the perfect normalization of its response is achieved only when both plasma insulin concentration and glycemic control simulate those of healthy subjects.

Two forms of α-glucosidase from sugar-beet seeds

Two forms of α-glucosidase (EC 3.2.1.20), designated as I and II, have been isolated from sugarbeet (Beta vulgaris L.) seeds by a procedure including fractionation with ammonium sulfate and ethanol, carboxymethyl-cellulose column chromatography, and preparative disc gel electrophoresis. The two enzymes were homogeneous by polyacrylamide disc gel electrophoresis. Their molecular weights were 98,000 (I) and 60,000 (II). α-Glucosidase I readily hydrolyzed maltose, isomaltose, kojibiose, maltotriose, panose, amylose, soluble starch, amylopectin and glycogen. α-Glucosidase II also hydrolyzed maltose, kojibiose and maltotriose but hydrolyzed the other substrates only very weakly or not at all. α-Glucosidase I hydrolyzed soluble starch at a faster rate than maltose. It produced isomaltose and panose as the main α-glucosyltransfer products from maltose, whereas maltotriose was the main product of α-glucosidase II. α-Glucosidase I hydrolyzed amylose liberating α-glucose. The neutral-sugar content was calculated to be 2.7% for α-glucosidase I and 8.8% for α-glucosidase II. The main neutral sugar was mannose in α-glucosidase I, and glucose in α-glucosidase II.

Counterregulatory system in an artificial endocrine pancreas. Glucose infusion algorithm

An artificial endocrine pancreas has been developed by adding a glucose infusion system to the artificial beta cell system. In this computer algorithm, glucose is infused on the basis of proportional and derivative actions to blood glucose concentration with the time delay constant between blood withdrawal and initiation of glucose infusion. When glucose was infused on the basis of proportional action with a 20-minute time delay, the prompt restoration to normoglycemia from the hypoglycemic state with a smaller amount of glucose was shown in depancreatized dogs. These results indicate that the artificial endocrine pancreas thus prepared is not only a useful device to safely control blood glucose, but also is an efficient research tool for the analysis of the blood glucose regulatory mechanism.

Validation of I.V. small-dose insulin infusion therapy in diabetic ketoacidosis of depancreatized dogs

A validation of small-dose insulin infusion therapy was studied by the constant i.v. infusion of various doses of insulin into ketoacidotic depancreatized dogs. Constant insulin infusion of 5 x B, 10 X B, 30 X B and 50 X B (B = 225 microunit/kg/min) was performed for 3 h by mechanical pump. The following results were obtained: (1) plasma concentrations of immunoreactive insulin (IRI) increased proportionally to the dose of infused insulin, but the higher IRI did not result in a greater fall in plasma glucose concentration, correspondingly; the mean rate of fall in plasma glucose concentration of 5 x B was not significantly lower than that of 50 x B; beta-hydroxybutyrate and arterial pH improvements were observed in each group during the 3-h insulin infusion. These data suggested that for the improvement of diabetic ketoacidosis, the insulin infusion rate of more than 30 x B, which raised the plasma IRI levels above the physiological range, was not essential; (2) the necessity of potassium supplementation during the small-dose insulin infusion was suggested if the pre-treatment level of serum potassium was low. These results confirmed that in the absence of infection or severe acidosis small-dose insulin infusion therapy is as effective as the conventional large-dose insulin therapy.

Increased intestinal absorption of insulin in a micellar solution: water-in-oil-in-water insulin micelles

Water-in-oil-in-water (W/O/W) insulin micelles were prepared, and the possibility of insulin absorption in a micellar form was examined. In this preparation, insulin was trapped in oil droplets of oleic acid in glyceryl-alpha-monooleate. (1) W/O/W insulin micelles were absorbed from the ligated jejunal loop of rabbits to the order of 12.3 to 58.5% of the dose given (10 mU/kg body weight) during the 3-h experimental period. (2) Alloxan diabetic rats were treated with intrajejunal administration of W/O/W insulin micelles at a dosage of either 25 or 50 mU/100 g body weight, three times daily for as long as 14 days. During treatment, a significant reduction in the daily excretion of urinary glucose was observed, concomitant with a decrease in fasting blood glucose. Quantitative estimates suggested that the effectiveness of 25 mU/100 g of intrajejunal W/O/W insulin micelles was comparable to that of regular insulin at a dosage of 1 mU/100 g i.m. These results would indicate that W/O/W insulin micelles, when given enterally, are more effective in lowering blood and urinary glucose levels than W/O/W insulin emulsions in which insulin was trapped in oil droplets of triglyceride.

Importance of insulin secretion based on the rate of change in blood glucose concentration in glucose tolerance, assessed by the artificial beta cell

The dynamic property of glucose-induced insulin secretion was simulated with the aid of a control theory, and the relationship between the stepwise input of glucose concentration and the biphasic response of insulin as an output was expressed in the transfer function of proportional plus derivative action to glucose concentration. By utilizing this model, the following computer algorithm for the artificial beta cell was made; rate of insulin infusion = Kp BG + Kd ΔBG+ Kc, where BG was the abbreviation for glucose concentration, ΔBG was the rate of change in BG, Kp and Kd were the coefficient for the proportional and derivative action, respectively, and Kc the constant for basal insulin secretion.

Microcomputer, insulin pump and digital printer were packed in small case, which was connected with glucose analyzer.

Experiments were carried out in the depancreatized dogs to validate the importance of infused insulin based on derivative action to glucose concentration in glucose regulation. Kd/Kp ratio was changed when insulin was infused following iv glucose bolus injection. The results revealed that when the derivative action was added to the proportional action properly in insulin infusion regulatory system, insulin requirement was the smallest and glucose regulation was the best.

The characteristics of the system recognized in clinical application were 1) rate of insulin infusion was small enough to keep the plasma concentration of insulin at a physiological level, then insulin requirements were reduced to around a half of those given subcutaneously, 2) glucose or glucagon to restore hypoglycaemia was not essential.

Induction of ornithine decarboxylase in cultured mouse L cells. II. Effects of additions of amino acids and serum

Induction of ornithine decarboxylase [EC 4.1.1.17] (ODC) in mouse L cells by components of the culture medium was investigated. It was found that further addition of amino acid mixture, but not of calf serum, to confluent cells of 5 day culture induced ODC and that this induction was accelerated by actinactinomycin D. In salt solution, addition of either amino acids or serum alone did not cause full induction, but addition of both together did. This induction, in contrast, was inhibited by actinomycin D. Induction by insulin, but not by cyclic AMP, was enhanced by a higher concentration of amino acids. These results can be explained by supposing that in non-growing cells there is stable RNA which is involved in ODC induction, possibly mRNA of ODC, and that the observed induction is caused by inhibition of enzyme degradation and accelerated translation, while in growing cells this RNA is unstable and ODC induction is controlled at the level of transcription.

Induction of ornithine decarboxylase in cultured mouse L cells. I. Effects of cellular growth, hormones, and actinomycin D

The activity of ornithine decarboxylase [EC 4.1.1.17] (ODC) in mouse L cells in the confluent state was induced within 4 hr by cyclic AMP (cAMP) or by insulin. During growth of L cells the concentration of cAMP increased first, then induction of ODC occurred and finally the cell number increased: the levels of cAMP and ODC increased only transitorily and returned to the basal levels when the cells become confluent. In growing cultures, however, the presence of cAMP reduced induction of ODC and cell growth. These results suggest that cAMP is involved in induction of ODC and that its concentration may be important for enzyme induction as well as for cell growth. Actinomycin D with or without these inducers stimulated induction of ODC in L cells, whereas cycloheximide inhibited it, suggesting that these hormones affect the translational level of ODC synthesis. The effect of actinomycin D on induction of ODC was much greater in non-growing cells than in growing cells. It was also found that the half life of ODC was 81 min in non-growing cells and 112 min in growing cells. This suggests that turnover of the enzyme is more rapid in the non-growing than in the growing state and that there may be an RNA fraction which controls its turnover and which also has a very short half life.