Influence of ingested load on postprandial insulin secretion. Rôle of gastric inhibitory polypeptide (GIP)

Two standard mixed meals including the same ingredients, and with different caloric values were ingested by 10 normal subjects. The plasma gastric inhibitory polypeptide (GIP) and immunoreactive insulin (IRI) as well as blood glucose (BG) were assayed during these meals at 0 (beginning of the meal) and after 30, 60, 120 and 180 min. BG was not significantly different between the two meals. At 30 min, the GIP peak was significantly higher in the case of the meal with the highest caloric (HC) value (499.5 +/- 112.0 vs. 273.4 +/- 57.5 pg/ml). Insulin was higher as well, although not in a significant way. At 120 min, the IRI was significantly higher (63.0 +/- 9.8 vs. 34.4 +/- 6.2 microU/ml) in the case of the HC meal. The HC meal induced a significantly higher insulinogenic index (0.29 +/- 0.05 vs. 0.14 +/- 0.07 mU litre g-1 ml-1). Integrated IRI and GIP responses of the HC meal were significantly higher than those of the meal with the lowest caloric value (IRI : 7.9 +/- 1.1 vs. 4.9 +/- 0.6 mU ml-1 180 min-1; GIP : 53.3 +/- 20.5 vs. 28.2 +/- 9.9 ng ml-1 180 min-1). The early (30 min) augmentation of IRI secretion after the ingestion of a larger meal is related to the insulinotropic action of the enhanced GIP secretion. The reasons for the late IRI increase are not obvious from this experiment. They might be of neural, nutrient, and/or intestinal origin.

Time-series analysis of stereotyped movements: relationship of body-rocking to cardiac activity

The pathological stereotypies frequently observed among severely mentally retarded and autistic persons are highly rhythmical in nature. Most attempts to quantify such behavior, however, have not analyzed stereotypy in terms of its cyclical properties. In the present paper we have detailed a method for electronically transducing stereotyped body-rocking and analyzing its frequency and amplitude characteristics with a standard polygraph and microprocessor. The relationship between stereotyped body-rocking and cardiac activity was also described using time-series analysis. The method described should provide a sensitive index of various experimental manipulations and treatment effects.

Long-term evolution of the effect of bran ingestion on meal-induced glucose and insulin responses in healthy man

The long-term effect (7 wk) of the addition in the diet of 20 g of wheat bran was studied in five healthy subjects. Blood glucose and plasma insulin were assayed during test-meals taking place before (I), then 10 days (II), 24 days (III), and 45 days (IV) after daily ingestion of wheat bran. Bran addition leads to a time progressive reduction of meal-induced glucose response. This effect was the strongest during meal III, at 30 min (from 7.38 +/- 0.11 to 5.0 +/- 1.11 mmol/l; p less than 0.05) and at 60 min (from 5.94 +/- 0.61 to 3.88 +/- 0.78 mmol/l; p less than 0.05). Insulin response remained identical during the first three test meals. It increased then in a significant manner during meal IV, at 60 min (From 45.5 +/- 12.3 to 61.8 +/- 8.9 microU/ml; p less than 0.02), and at 120 min (from 41.2 +/- 16.3 to 61.0 +/- 16.0 microU/ml; p less than 0.05). The causes of the reduction of glucose response could be potential gastric emptying and intestinal transit increases. The exact mechanism of the improved long-term glucose tolerance seen in brain is not obvious nor is the reason for the enhanced insulin response seen later.

Nightly amended IRI/BG ratio in fasting test during sleeping periods in subjects with insulinoma and in normal, diabetic and obese subjects

In order to obtain a dynamic picture of the way abnormal insulinemia, as a function of blood glucose, occurs in the morning in subjects with insulinoma, we have measured amended plasma insulin (IRI)/blood glucose (BG) ratio during the fasting period of 4 sleeping subjects with insulinoma. Healthy subjects and subjects suffering from other diseases were used as reference in order to determine variations of this ratio during the night. BG and IRI were assayed at intervals of 15 or 30 min. Subjects with insulinoma differed from the other subjects by a very elevated ratio dispersion around the mean value with highly significant peaks (greater than 100). Mean value always remained outside the range (7-82) which covers the total range of values measured in healthy and pathological subjects.

[Plasma glucose and C-peptide after ingestion of sucrose and starch in controlled insulin-dependent diabetics. Importance of glucose availability]

Oral tests using 50 g of sucrose and 100 g of white bread were carried out in ten insulin-dependent diabetics (four with signs of residual B-cell function and in six without). Plasma glucose and C-peptide (CPR) were estimated during the 180 minutes after ingestion. After bread intake, plasma glucose increase was significantly delayed (30 min.). Hyperglycemia (greater than 2.5 g/l) lasted significantly longer after bread then after sucrose ingestion. Blood glucose decreased more quickly in subjects with residual B-cell function than in subjects without. CPR was not significantly modified by either of the carbohydrate loads. In the controlled insulin-dependent diabetic the hyperglycemia observed results from the ease of carbohydrates hydrolysis and from the amount of available glucose. The role of fructose seems weak in the case of sucrose because its conversion to glucose would be minimized in the presence of metabolic normalization as indicated by a well controlled blood glucose.

Intravenous disopyramide: safety and efficacy of a new dosage regimen

The efficacy and safety of a new dosage regimen of intravenous disopyramide in ventricular arrhythmias were evaluated in 10 patients. Each had at least four premature ventricular contractions (PVCs)/min during a 30-min period before dosing. By the classification of Lown et al., grade III arrhythmia was present in four patients, grade IVA in three patients, and grade IVB in three patients. Disopyramide was injected intravenously as a bolus of 0.5 mg/kg over 5 min. Each patient received two to three additional boluses of same strength with 5-min intervals between each dosing during the first hour. Continuous intravenous infusion was started with the first bolus and continued at a rate of 1 mg/kg/hr for 3 hr and at 0.4 mg/kg/hr for 15 hr. All patients had continuous Holter monitoring throughout the 18-hr treatment period and for 30 to 60 min before treatment. In eight patients the grade of arrhythmia after drug decreased and the frequency of PVCs fell by 70% to 100% (greater than 85% in six patients and less than 85% in two patients), and the response persisted during the continuous infusion. In two patients PVC frequency increased. For the group as a whole, PVC frequency decreased on the average by 68.4%. Therapeutic serum levels (greater than 2 micrograms/ml) were reached after the first or second bolus and were maintained during the continuous infusion period. There were no side effects necessitating termination of disopyramide infusion. The dosage regimen of intravenous disopyramide evaluated was effective in 60% of patients with ventricular arrhythmia, induced no severe toxic effects, and rapidly achieved therapeutic serum levels that were maintained during continuous infusion.

Influence of caloric intake on gastric inhibitory polypeptide, VIP and gastrin release in man

Blood glucose, gastric inhibitory polypeptide (GIP), vasoactive intestinal polypeptide (VIP) and gastrin secretions were measured over a three-hour period following the ingestion by normal subjects of a mixed meal with two different caloric levels (1055 Kcal and 1192 Kcal). No VIP secretion was observed after either meal. Gastrin release was not modified by the increase of caloric intake (mainly carbohydrates and lipids), whereas GIP secretion was significantly more important after the meal with the highest caloric value (peak at 30 mm: 499.5 +/- 250.4 vs. 273.4 +/- 128.7 pg/ml and integrated response 53.3 +/- 20.5 vs. 28.2 +/- 9.9 ng X ml-1 X 180 min-1-p less than 0.05). This difference could not be attributed to glucose since the blood glucose levels were not significantly different. It is more probably related to the total amount of ingested food. This suggests the existence of rapid mechanisms of adaptation to the incoming load of the GIP-producing cells.

Carrier detection and X-inactivation studies in the fragile X syndrome. Cytogenetic studies in 63 obligate and potential carriers of the fragile X

Cytogenetic investigations by three different lymphocyte culture methods in 63 obligate and potential carriers of the fragile X [fra(X)] are reported. A difference was observed between normal and retarded carriers in the manifestation of the fra(X). An inverse relationship between percentage positive cells and age was demonstrated in normal carriers, whereas retarded carriers generally showed higher percentages at all ages. X-inactivation studies in retarded carriers compared with normal carriers showed a tendency towards a skewed inactivation pattern with an excess of early replicating fra(X) in both groups when carriers expressing high percentages of fra(X) positive cells were compared. In normal carriers with low percentage expression the tendency was apparently reversed. The relationship between the replication pattern of the fragile X and the mental status of the individual is more complicated than suggested by previous studies.

Gastric inhibitory polypeptide enhancement of the insulin effect on fatty acid incorporation into adipose tissue in the rat

The influence of gastric inhibitory polypeptide (GIP) on fatty acid incorporation into adipose tissue (FIAT) was studied in the rat on epididymal fat pads at concentrations amounting to 1, 2 and 4 ng/ml. Without insulin in the incubation medium, GIP induced a slight though significant FIAT decrease with a maximum of 9% for 2 ng/ml concentration. In the presence of rat insulin (100 microU/ml), it significantly enhanced the insulin-induced FIAT increase, that progressed from 106.4% of the basal value to 110.5% for 1 ng/ml concentration (P less than 0.025) and to 118.2% for 4 ng/ml concentration (P less than 0.0025). The existence of such a phenomenon as well as that of an hyperactive enteroinsular axis in obese subjects could represent two important factors in the development of obesity.

Pregnancy-associated plasma protein A: a possible marker in the classification and prenatal diagnosis of Cornelia de Lange syndrome

The concentration of human platelet lactogen (hPL), pregnancy specific beta-1 glycoprotein (SP-1) and pregnancy-associated plasma protein A (PAPP-A) were analysed in consecutive serum samples from a patient who gave birth to a child with Cornelia de Lange syndrome. HPL and SP-1 were present in normal concentrations from week 20 to week 35 of gestation whereas PAPP-A could not be detected in any of the samples examined. Immunohistochemical examination of two placentae from Cornelia de Lange syndrome revealed normal localization of hPL and SP-1 but the absence of PAPP-A from the syncytiotrophoblast. The significance of association between Cornelia de Lange syndrome and compromised synthesis of PAPP-A is discussed.

Diagnostic and therapeutic aspects of dihydrobiopterin deficiency

The first Scandinavian hyperphenylalaninaemic patient with a cofactor deficiency is described. By neonatal screening the Guthrie test showed a serum phenylalanine of 302 mumol/1 (5 mg/dl), which at age 6 weeks had fallen to high normal values. At age 5 1/2 months the serum phenylalanine was around 2000 mumol/1 and the child presented with severe neurological symptoms. The diagnosis of defect dihydrobiopterin biosynthesis was made by high performance liquid chromatography of the urine. Loading tests followed by daily treatment of the missing cofactor was able to keep the serum phenylalanine in the normal level. Because of persisting, yet diminishing neurological symptoms neurotransmitter treatment was started. Breast feeding as the cause of the low neonatal levels of serum phenylalanine and the late start of clinical symptoms is proposed and the importance of screening all hyperphenylalaninaemic newborns for defect biopterin metabolism is stressed.

In vitro existence of a trypsin dependent C-peptidase in human plasma. Discussion of its possible role in vivo

The C-peptide immunoreactivity (CPR) is markedly increased after a short incubation of human plasma with trypsin. Three experiments (study of the action of trypsin-treated plasma on labelled CPR, precipitation of plasma proteins with polyethylene glycol, CPR measurement with three different radioimmunoassays kits) were made in order to account for this phenomenon. The concordant results obtained and the inhibitory action of aprotinin observed in these experiments led us to conclude to the existence in plasma of a trypsin dependent C-peptidase with a specificity for the COOH terminus of the complete CPR (Arg - Arg - C-peptide - Lys - Arg). The role of this protease is probably minor in the C-peptide degradation process but could have an effect on the insulin catabolism through the existence of the alpha 2 - macroglobulin - trypsin complexes and insulin protease. This suggests a possible influence of the exocrine pancreas on the endocrine pancreas.

[Evaluation] of chronic dust-induced bronchitis as an occupational disease]

Recommendations for announcement and legal recognition of dust induced chronic bronchitis are presented. They rely on practice and aim for improvements and support for decision finding in medical reports. Basic criteria for legal recognition are intensity and duration of exposure, temporal relations between development of disease and exposure as well as type and grade of disease. The problem of demarcating non-occupational factors of influence is discussed. Legal recognition of dust induced bronchitis as an occupational disease can be achieved in a a special procedure.

Portal, hepatic and peripheral insulin immunoreactive substances before and after removal of an insulinoma

Plasma insulin immunoreactivity (IRI) results from high molecular weight substances with insulin immunoreactivity (HWIRI), proinsulin (PI) and insulin (I). Their respective concentrations and percentages of IRI were determined preoperatively in the hepatic and peripheral circulations and after surgery in the latter two and in the portal circulation in a patient with a pancreatic adenoma. Removal of the insulinoma resulted in a highly significant reduction of PI concentration in the hepatic (from 16.2 +/- 1.9 microU/ml to 7.3 +/- 0.8 microU/ml) and in the peripheral (from 24.0 +/- 2.0 microU/ml to 9.2 +/- 1.2 micro U/ml) venous systems. Similarly, I concentration decreased in the hepatic (from 36.9 +/- 3.4 microU/ml to 28.0 +/- 1.0 microU/ml) and peripheral (from 33.8 +/- 3.4 microU/ml to 19.8 +/- 2.0 microU/ml) venous systems. HWIRI concentration decreased in the hepatic venous system (from 6.9 +/- 0.8 microU/ml, to 4.8 +/- 0.6 microU/ml), but the decrease in the peripheral venous system (from 9.7 +/- 1.4 microU/ml to 8.2 +/- 1.2 microU/ml) was not significant. It was found that the concentration of I virtually was the same in hepatic and peripheral blood prior to operation in contrast to a decrease seen after the operation. This indicates that the hyperinsulinemia caused primarily by the autonomous hypersecretion of the insulinoma was amplified by a decreased degradation of insulin by the liver and kidney. Our results also indicate that HWIRI was found with the highest concentration in the peripheral blood independently of the adenoma.

Induction of chronic bacterial prostatitis in the dog

Three methods of creating chronic bacterial prostatitis in dogs were evaluated. Injection of Escherichia coli into the prostatic or caudal vesicle artery after the prostate was pierced with a 22-gauge needle caused prostatic infection in 4 of 5 dogs. The infection persisted up to 28 days. Direct injection of E. coli into the prostate gland resulted in infection in 5 of 6 dogs which persisted up to 42 days. Injection of E. coli into the prostatic urethra after occlusion of the bladder neck caused infection in 2 of 8 dogs not subjected to piercing of the prostate gland and in 5 of 7 dogs subjected to prostate gland trauma. Infection persisted up to 28 days. Although all 3 methods resulted in persistent, chronic bacterial prostatitis, direct injection of bacteria into the prostate gland was technically the easiest to perform and resulted in the lowest incidence of concomitant infections of the rest of the urinary tract. Positive urine cultures for E. coli were found in all dogs at some time after infection. Positive urine and bladder tissue cultures were also found at necropsy in some dogs.

Clinical aspects of GIP secretion

The gastric inhibitory polypeptide (GIP) is the main hormone of the incretin type acting on the entero-insular axis. It is released after fat, glucose or meal ingestion. The variations of this secretion are described in obesity and in some pancreatic and gastrointestinal diseases: it is increased in maturity onset diabetes mellitus, obesity or duodenal ulcer, variable according to the food taken and the severity of the pancreatic lesion in chronic pancreatitis and cystic fibrosis, normal in insulinoma and decreased in celiac disease. The impaired absorption of the food-stuffs and the defective feed-back regulation of GIP secretion by insulin are the major causes of these variations. To a lesser degree, gastric acid secretion, gastric emptying and vagal control may also influence GIP secretion.

Malignant pericardial mesotheliomas and asbestos exposure: a case report

Three cases of malignant pericardial mesotheliomas are presented with evidence of occupational asbestos exposure. Examination results are compared with findings from experimental and epidemiological research on biological effects of asbestos dust. There are sufficient indications that time-limited effects of asbestos dust established either by measurements or assessment of the amount of concentration after a latency of more than 20 years are apt to result in the development of mesotheliomas of the pleura and peritoneum and, moreover, the pericardium. It is suggested that malignant pericardial mesothelioma also be recognized as another form of occupational disease caused by asbestos dust.

Hyperinsulinemia associated with normal C-peptide levels in a woman treated with isoniazide

The authors report on the observation of a woman treated with isoniazide, who presented clinical symptoms of hypoglycemia during treatment (seating, confusion, anxio-depressive syndrome, lipothymia). After the antitubercular treatment was stopped, a moderate hypoglycemia without clinical manifestations accompanied by a marked hyperinsulinemia and normal C-peptide values was detected during a Conn's test. Serum gel filtration on Sephadex G 50 Fine showed that the measured hyperinsulinemia was effectively due to an insulin excess. This excess did not seem caused by surreptitious insulin injection. This seems to be the consequence of a deficiency in insulin catabolism because the C-peptide level was normal. The possible role of isoniazide on carbohydrate metabolism is discussed.

Effect of a dietary protein deficiency on the development of hepatic drug-metabolizing enzymes in young rats

The effect of protein deprivation on the activities of hepatic drug-metabolizing enzymes was studied in young rats whose mothers had previously been on a protein-restricted diet during pregnancy. Dietary protein deficiency (5% lactic casein as the protein source) lowered the amount of cytochrome P-450 and the activities of epoxide hydrolase and UDP-glucuronosyltransferase (UDPGT) (l-borneol as the substrate) by about 45, 63, and 48%, for the first 8 weeks, respectively. Interestingly, UDPGT estimated with p-nitrophenol as the substrate was far less affected than that estimated from l-borneol glucuronidation. This finding provides further evidence of the heterogeneity of UDPGT. Restoration of a balanced diet for 15 days following protein deprivation quickly restored cytochrome P-450 and enzyme activities to control values. Our experiments showed that the development of drug-metabolizing enzymes was changed more by the diet in young rats than in older rats. This could affect the toxicity of drugs that are normally metabolized by these pathways.