Biomedical subjects

O Rasmussen

Publications and source records attributed to O Rasmussen.

At least 37 records · Page 2Linked to original sources

PubMed1993

Day-to-day variation of the glycemic response in subjects with insulin-dependent diabetes with standardized premeal blood glucose and prandial insulin concentrations.

To study the day-to-day variation in the glycemic response to a starch-rich meal in subjects with insulin-dependent diabetes mellitus (IDDM), eight young subjects with IDDM were served test meals of 100 g white bread on 3 separate days. They had achieved normoglycemia 2 h before the test meals by means of a glucose clamp and a constant insulin infusion was provided during the study period. Mean areas under the response curves of blood glucose to the three meals (above basal) were not different: 1067 +/- 93, 1028 +/- 91, and 970 +/- 42 mmol/L x 180 min (NS) and no difference in insulin concentrations was found. The mean (+/- 95% confidence interval) of blood glucose area under the response curves for one test meal was 1067 +/- 230 mmol/L x 180 min and for the test meal repeated three times was 1021 +/- 133 mmol/L x 180 min. Intra- and interperson components of variance were 26% and 74%, respectively, of the total variance of blood glucose areas.

Adult↗

PubMed1993

Wine for type 2 diabetic patients?

To ensure an acceptable quality of life for Type 2 diabetic patients, the food recommendations have to be as liberal and individualized as possible. Unfortunately, disagreements exists about the consumption of different types of wine. Diabetic patients are advised by some to restrain their wine intake and to use dry wine containing little carbohydrate, while others are more liberal. The purpose of this study was to evaluate the effects of dry and sweet wine on the glycaemic control in Type 2 diabetes. Twelve diabetic patients consumed a light meal with either 300 ml tap water 300 ml dry white wine, 300 ml sweet white wine with ethanol added or 300 ml dry white wine with glucose added. Similar glucose, insulin, and triglyceride responses were obtained in all four situations. There was a greater suppression of the free fatty acid levels in the three situations with wine as compared with water (p < 0.001). This effect may be caused by an attenuation of the free fatty acid mobilization and esterification of free fatty acids to triglycerides induced by alcohol. Our results indicate that patients with well-controlled Type 2 diabetes can drink moderate amounts of wine with meals without risking acute deterioration of glycaemic control. Whether the wine is dry or sweet has no impact on the glycaemic control.

Adult↗

PubMed1993

Effect of meal frequency on blood glucose, insulin, and free fatty acids in NIDDM subjects.

OBJECTIVE: We studied the effects of meal frequency on blood glucose, serum insulin, and FFAs in 12 NIDDM subjects. RESEARCH DESIGN AND METHODS: Subjects were assigned in random order to two 8-hr observation periods after an overnight fast. They received isocaloric diets with similar composition either as six small or as two large meals. At the end of each study period, an IVGTT was given. RESULTS: Two large meals induced an 84% greater maximum amplitude of glucose excursions than six small meals (6.1 +/- 0.5 vs. 3.3 +/- 0.5 mM, P < 0.005) and higher insulin responses (P < 0.03). The Kg response to an IVGTT did not differ in the two situations. The average FFA level was lowest in response to frequent meals (P < 0.02). CONCLUSIONS: A higher meal frequency acutely subdues glucose excursions and reduces insulin and FFA levels during the daytime in older NIDDM subjects.

Blood Glucose↗

PubMed1993

Acute effects of graded alcohol intake on glucose, insulin and free fatty acid levels in non-insulin-dependent diabetic subjects.

Alcohol-induced hypoglycaemia is a well-known phenomenon in insulin-treated diabetic subjects. Less attention has been paid to the impact of alcohol on blood glucose and insulin responses in non-insulin dependent diabetic subjects. The aim of this study was to investigate the acute metabolic effects of different alcohol contents added to a non-alcohol beer in 10 non-insulin-dependent diabetes mellitus (NIDDM) subjects. The patients received 500 ml non-alcohol beer with an alcohol percentage (v/v) of 0 (A), 2.7 (B), and 5.4 (C), implying identical contents of ingredients except for alcohol. Blood glucose (mean +/- SE) responses were similar in the three situations (395 +/- 59, 365 +/- 86 and 261 +/- 26 mmol/l x 240 min). In contrast, the incremental insulin response areas increased dose dependently to alcohol (5430 +/- 1158, 9336 +/- 2172 and 12336 +/- 2922 pmol/l x 240 min) and showed a linear correlation (r = 0.39; P < 0.03). The average suppression of serum free fatty acid was similar in the three situations (72.4 +/- 4.4%, 76.3 +/- 6.0% and 68.2 +/- 6.3%). In conclusion, intake of small amounts of alcohol does not acutely deteriorate the glycaemic control in NIDDM. The fact that alcohol results in a dose-related elevation in insulin levels with unaltered blood glucose and free fatty acid responses in NIDDM points to an aggravation of insulin resistance.

Aged↗

PubMed1992

The effect of microgravity on the development of plant protoplasts flown on Biokosmos 9.

An experiment using plant protoplasts has been accepted for the IML-1 Space Shuttle mission scheduled for 1991. Preparatory experiments have been performed using both fast and slow rotating clinostats and in orbit to study the effect of simulated and real weightlessness on protoplast regeneration. Late access to the space vehicles before launch has required special attention since it is important to delay cell wall regeneration until the samples are in orbit. On a flight on Biokosmos 9 ("Kosmos-2044") in September 1989 some preliminary results were obtained. Compared to the ground control, the growth of both carrot and rapeseed protoplasts was decreased by 18% and 44% respectively, after 14 days in orbit. The results also indicated that there is less cell wall regeneration under micro-g conditions. Compared to the ground controls the production of cellulose in rapeseed and carrot flight samples was only 46% and 29% respectively. The production of hemicellulose in the flight samples was 63% and 67% respectively of that of the ground controls. In both cases all samples reached the stage of callus development. The peroxidase activity was also found to be lower in the flight samples than in the ground controls, and the number of different isoenzymes was decreased in the flight samples. In general, the regeneration processes were retarded in the flight samples with respect to the ground controls. From a simulation experiment for IML-1 performed in January 1990 at ESTEC, Holland, regenerated plants have been obtained. These results are discussed and compared to the results obtained on Biokosmos 9. Protoplast regeneration did not develop beyond the callus stage in either the flight or the ground control samples from the Biokosmos 9 experiment.

Brassica↗

PubMed1992

Structural and functional organisation of regenerated plant protoplasts exposed to microgravity on Biokosmos 9.

Preparatory experiments for the IML-1 mission using plant protoplasts, were flown on a 14-day flight on Biokosmos 9 in September 1989. Thirty-six hours before launch of the biosatellite, protoplasts were isolated from hypocotyl cells of rapeseed (Brassica napus) and suspension cultures of carrot (Daucus carota). Ultrastructural and fluorescence analysis of cell aggregates from these protoplasts, cultured under microgravity conditions, have been performed. In the flight samples as well as in the ground controls, a portion of the total number of protoplasts regenerated cell walls. The processes of cell differentiation and proliferation under micro-g did not differ significantly from those under normal gravity conditions. However, in micro-g differences were observed in the ultrastructure of some organelles such as plastids and mitochondria. There was also an increase in the frequency of the occurrence of folds formed by the plasmalemma together with an increase in the degree of complexity of these folds. In cell cultures developed under micro-g conditions, the calcium content tends to decrease, compared to the ground control. Different aspects of using isolated protoplasts for clarifying the mechanisms of biological effects of microgravity are discussed.

Brassica↗

PubMed1992

Influence of the amount of starch on the glycaemic index to rice in non-insulin-dependent diabetic subjects.

To test whether the glycaemic index is altered by the amount of carbohydrate, meals containing 25 and 50 g carbohydrate as white rice and white bread were taken by seven non-insulin-dependent diabetic subjects. The glycaemic indices to parboiled white rice corresponding to 25 and 50 g carbohydrate were similar, being 55 (SE 10) and 60 (SE 8) respectively. The incremental areas of blood glucose (above basal) to parboiled white rice were significantly lower than to white bread after both an amount corresponding to 25 g carbohydrate (85 (SE 24) mM x 180 min v. 181 (SE 55) mM x 180 min; P less than 0.01) and to 50 g carbohydrate 226 (SE 29) mM x 180 min v. 423 (SE 76) mM x 180 min; P less than 0.01). Similar insulin response areas to 25 g carbohydrate given as parboiled white rice and white bread were found, whereas 50 g carbohydrate as white bread caused a significantly higher insulin response area than parboiled white rice (P less than 0.05). In conclusion, the glycaemic index of parboiled white rice is not affected by the amount of carbohydrate ingested, at least under the present study conditions.

Blood Glucose↗

PubMed1992

Influence of ripeness of banana on the blood glucose and insulin response in type 2 diabetic subjects.

Banana is a popular and tasty fruit which often is restricted in the diet prescribed for diabetic patients owing to the high content of free sugars. However, in under-ripe bananas starch constitutes 80-90% of the carbohydrate content, which as the banana ripens changes into free sugars. To study the effect of ripening on the postprandial blood glucose and insulin responses to banana, 10 type 2 (non-insulin-dependent) diabetic subjects consumed three meals, consisting of 120 g under-ripe banana, 120 g over-ripe banana or 40 g white bread on separate days. The mean postprandial blood glucose response area to white bread (181 +/- 45 mmol l-1 x 240 min) was significantly higher compared with under-ripe banana (62 +/- 17 mmol l-1 x 240 min: p < 0.01) and over-ripe banana (106 +/- 17 mmol l-1 x 240 min: p < 0.01). Glycaemic indices of the under-ripe and over-ripe bananas differed (43 +/- 10 and 74 +/- 9: p < 0.01). The mean insulin response areas to the three meals were similar: 6618 +/- 1398 pmol l-1 x 240 min (white bread), 7464 +/- 1800 pmol l-1 x 240 min (under-ripe banana) and 8292 +/- 2406 pmol l-1 x 240 min (over-ripe banana). The low glycaemic response of under-ripe compared with over-ripe bananas may be ascribed to the high starch content, which has previously been found to be only hydrolysed slowly by alfa-amylase in humans.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Glucose↗

PubMed1992

Assessment of glucose turnover rates in euglycaemic clamp studies using primed-constant [3-3H]-glucose infusion and labelled or unlabelled glucose infusates.

Underestimation of glucose turnover rates has been a problem in clamp studies using primed-constant [3-3H]-glucose infusion technique. Due to slow mixing in interstitial compartments concealed specific activity gradients may arise between plasma and interstitial compartments during intravenous unlabelled glucose infusion. Such specific activity gradients, however, can be prevented if plasma specific activity is maintained constant. Two euglycaemic clamp studies (insulin infusion 40 mU m-2 min-1) were performed in six lean normal subjects. Using conventional unlabelled glucose infusates plasma specific activity declined by 74%, tracer determined glucose appearance was smaller than actual glucose infusion rates (317 +/- 11 vs 366 +/- 15 mg m-2 min-1, p < 0.001), and erroneous negative values were calculated for glucose production (- 49 +/- 7 mg m-2 min-1). Average underestimation during the first 2 h correlated with glucose infusion rates (r = 0.88, p < 0.02). In contrast, when plasma specific activity was maintained constant, using appropriately labelled glucose infusates, tracer determined glucose appearance and glucose infusion rates were similar (385 +/- 16 vs 385 +/- 17 mg m-2 min-1), and negative errors for glucose production were avoided. In conclusion, using unlabelled glucose infusates, as in previous studies, suppression of glucose production is overestimated and stimulation of glucose utilization is underestimated. As errors were greater with larger glucose infusions, the mistakes may have been greatest in insulin sensitive control subjects, and smaller in insulin resistant subjects. Therefore, re-evaluation of hepatic insulin sensitivity seems appropriate in diabetes, obesity, and other insulin resistant states.

Adult↗

PubMed1992

The effect of exposure to microgravity on the development and structural organisation of plant protoplasts flown on Biokosmos 9.

Preparatory experiments for the IML-1 (International Microgravity Laboratory) mission to be flown on the Space Shuttle in January, 1992, were performed on a 14 day flight on Biokosmos 9 (Kosmos 2044) in September 1989. The purpose of the experiment was to study the effect of weightlessness on protoplast regeneration. Problems with late access to the space vehicle meant that the newly isolated protoplasts from hypocotyl cells of rapeseed (Brassica napus L. cv Niklas) and suspension cultures of carrot (Daucus carota L, cv Nobo) had to be stored at 4 degrees C for 36 h prior to the launch of the biosatellite, in order to delay cell wall regeneration until the samples were in orbit. In the flight samples and the ground controls, a portion of the total number of protoplasts regenerated cell walls. The growth of flight rapeseed cells was only 56% compared to the ground control; the respective growth of carrot cells in orbit was 82% of the ground control. Analysis demonstrated that the peroxidase activity and the amount of protein was lower in the flight samples than in the ground controls. The number of different isoenzymes was also decreased in the flight samples. A 54% decrease in the production of cellulose was found in rapeseed, and a 71% decrease in carrot. Hemicellulose production was also decreased in the flight samples compared to the ground controls. Ultrastructural analysis of the cell aggregates from the protoplasts cultured in orbit, demonstrated that hydrolysis and disappearance of reserve starch occurred in the flight cell plastids. The mitochondria were more varied in appearance in the flight samples than in the ground control cells. An increased frequency of the occurrence of folds formed by the plasmalemma together with an increase in the degree of complexity of these folds was also observed. Fluorescence analysis showed a decrease of the calcium content in cell cultures under space flight compared to the ground controls. One general effect of the stay onboard the space vehicle was a retardation of the regeneration processes. Callus cultures obtained from the flight samples grew very slowly compared to callus regenerated from the ground controls, and two years after the Biokosmos 9 flight there appears to be no further growth in the samples exposed to microgravity. Callus cultures from the ground controls, however, continue to grow well. A simulation experiment for IML-l performed in January 1990 at ESTEC (European Space Technology Center), The Netherlands, has resulted in regenerated plants. These observations are discussed and compared to the results obtained on Biokosmos 9.

Bioreactors↗

PubMed1992

Glycaemic and insulinaemic responses to orange and apple compared with white bread in non-insulin-dependent diabetic subjects.

To study the postprandial blood glucose and insulin responses to exchangeable amounts of simple and complex carbohydrates, eight non-insulin-dependent diabetic subjects consumed 227 g apple, 280 g orange or 50 g white bread on three separate days. The mean postprandial blood glucose response area to white bread (404 +/- 95 mM x 240 min) was significantly higher compared with orange (131 +/- 34 mM x 240 min; P less than 0.05) and apple (157 +/- 57 mM x 240 min; P less than 0.05). Thr glycaemic indices of the fruits were identical: 44 +/- 13 (orange) and 40 +/- 11 (apple). The low glycaemic response to orange and apple may be ascribed to the high content of fructose which is rapidly cleared and metabolized by the liver, without elevating the blood glucose.

Blood Glucose↗

PubMed1991

Direct regeneration of transformed shoots in Brassica napus from hypocotyl infections with Agrobacterium rhizogenes.

Genetically transformed root clones of rapeseed (Brassica napus) were obtained after in vitro infection of excised hypocotyl segments with a wild type strain of Agrobacterium rhizogenes and two strains of A. rhizogenes harbouring kanamycin resistance. The ability of hairy root formation was affected by light and was highly dependent on the location of the infection site at the hypocotyl. Inoculation of decapitated hypocotyls with an intact root system gave rise to direct shoot formation from the site of inoculation. Histological sections showed that several meristems were initiated at the inoculation site. Root and shoot clones were isolated and subcultured axenically in hormone-free liquid MS medium. Identification of transformed root and shoot clones was based on opine assays. Further selection was carried out in kanamycin-enriched medium. All opine-positive root clones showed NPT II (neomycin phosphotransferase) activity. Nearly half of the shoot clones expressed a strong NPT II activity while the rest gave a weak or no NPT II response.

Brassica↗

PubMed1991

Decreased hepatic glucagon responses in type 1 (insulin-dependent) diabetes mellitus.

The effect of glucagon infusion on hepatic glucose production during euglycaemia was evaluated in seven Type 1 (insulin-dependent) diabetic patients and in ten control subjects. In the diabetic subjects normoglycaemia was maintained during the night preceding the study by a variable intravenous insulin and glucose infusion. During the study endogenous insulin secretion was suppressed by somatostatin (450 micrograms/h) and replaced by insulin infusion (0.15 mU.kg-1.min-1). 3H-glucose was infused for isotopic determination of glucose turnover. Plasma glucose was clamped at 5 mmol/l for 2 h 30 min and glucagon (1.5 ng.kg-1.min-1) was then infused for the following 3 h. Hepatic glucose production and glucose utilisation were measured during the first, second and third hour of the glucagon infusion. Basal hepatic glucose production (just prior to glucagon infusion) was similar in diabetic (1.2 +/- 0.3 mg.kg-1.min-1) and control (1.6 +/- 0.1 mg.kg-1.min-1) subjects. In diabetic patients hepatic glucose production rose slowly to 2.1 +/- 0.5 mg.kg-1.min-1 during the first hours of glucagon infusion and stabilized at this level (2.4 +/- 0.5 mg.kg-1.min-1) in the third hour. In control subjects hepatic glucose production increased sharply to higher levels than in the diabetic subjects (3.4 +/- 0.3 mg.kg-1.min-1) during the first and second hour of glucagon infusion (p less than 0.05) and then gradually fell (2.9 +/- 0.4 mg.kg-1.min-1) during the third hour. In conclusion, when stimulated with glucagon at a physiologic plasma concentration diabetic patients had 1) an overall reduced hepatic glucose production response and 2) an abnormal sluggish response pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Hydroxybutyric Acid↗

PubMed1991

Preprandial blood glucose values and glycemic responses in insulin-dependent diabetes mellitus at constant insulinemia.

The influence of preprandial blood glucose (PPBG) concentration on glycemic responses was studied in seven subjects with insulin-dependent diabetes who, by means of the artificial pancreas, had achieved PPBG concentrations of 6, 9, and 17 mmol/L. A test meal of 50 g parboiled rice was given at the three different occasions and a constant insulin infusion was provided during the observation periods. The mean postprandial-blood-glucose-response area (above basal) differed significantly at the three blood glucose concentrations of 6, 9, and 17 mmol/L, reaching 1371, 621, and 179 mmol/L x 240 min, respectively (P less than 0.01). A negative correlation between the PPBG concentrations and the glycemic responses to the test meal was found (r = 0.94; P less than 0.001). The fasting insulin concentration at a PPBG concentration of 17 mmol/L was lower than at a PPBG concentration of 6 and 9 mmol/L. In conclusion, the glycemic responses to a carbohydrate meal are inversely correlated to the PPBG concentration in insulin-dependent diabetic subjects.

Adult↗

PubMed1991

Glycaemic responses to different types of bread in insulin-dependent diabetic subjects (IDDM): studies at constant insulinaemia.

To study the glycaemic effect of various Danish bread types in insulin-dependent diabetic subjects (IDDM) we looked at the incremental blood glucose areas after isocaloric meals of grained wholemeal rye bread, wholemeal bread (graham bread) and white bread in seven C-peptide negative diabetic subjects. Furthermore, we evaluated the glycaemic potency of dried fruits by exchanging 40 per cent of the starch of grained wholemeal rye bread as dried figs. Prior to the meal intake the patients had attained normoglycaemia and isoinsulinaemia by means of the artificial pancreas. The four test meals containing 50 g of available carbohydrate were taken in random order. The postprandial blood glucose response areas after whole-meal bread (1037 +/- 113 mM X 180 min) and white bread (1021 +/- 100 mM X 180 min) were significantly higher than that to grained wholemeal rye bread (786 +/- 66 mM X 180 min, P less than 0.05). Exchange of 40 per cent of the complex carbohydrate as grained wholemeal rye bread with simple sugars, such as figs, had no influence on the blood glucose response (786 +/- 66 mM X 180 min vs. 766 +/- 56 mM X 180 min). Constant and identical serum-free insulin levels at 30 mU/l and similar amounts of glucose lost in the urine were found after the four test meals. In conclusion, the difference in extraction rate of wheat in the form of white flour (0, 7) and wholemeal flour (1, 0) was not reflected in the glycaemic responses in IDDM subjects. Grained wholemeal rye bread is a fibre-rich, cheap nutrient which elicits a significantly lower glycaemic response compared to wholemeal and white bread and can be recommended to diabetic subjects.

Adult↗

PubMed1990

Rectal compliance in the assessment of patients with fecal incontinence.

Rectal compliance (dV/dP) was studied in 31 patients with fecal incontinence, 8 patients with constipation, and 16 control subjects. Patients with fecal incontinence experienced a constant defecation urge at a lower rectal volume and also had a lower maximal tolerable volume and a lower rectal compliance than control subjects (median 126 vs. 155 ml, 170 vs. 220 ml, and 9 vs. 15 ml/mm Hg, respectively; P less than 0.05). Constipated patients had a higher constant defecation urge volume and maximal tolerable volume than controls (median, 266 ml and 300 ml; P less than 0.05). There was no differences in the parameters between patients with idiopathic fecal incontinence and patients with incontinence of traumatic origin, indicating that a poorly compliant rectum in patients with fecal incontinence may be secondary to anal incontinence due to the lack of normal reservoir function.

Adult↗

PubMed1990

Water volume and consumption time: influence on the glycemic and insulinemic responses in non-insulin-dependent diabetic subjects.

The present study was carried out to see if either the volume of water or the duration of ingestion time influence the postprandial blood glucose and insulin responses in non-insulin-dependent diabetic (NIDDM) subjects. Small test meals containing 40 g carbohydrate as rye bread (100 g) with butter (10 g) and tomatoes (75 g) were given to 10 NIDDM subjects. The meals were taken in random order with either 90 or 600 mL tap water. The meal with 90 mL tap water was ingested over 10 and 30 min. The glycemic responses to isocaloric meals of large and small volumes were similar (338 +/- 56 vs 384 +/- 67 mmol/L.240 min) as were the insulinemic responses (29,424 +/- 6512 min vs 27,140 +/- 6548 mumol/L.240 min). An extension of eating time from 10 to 30 min did not alter the glycemic (384 +/- 67 vs 370 +/- 54 mmol/L.240 min) or the insulinemic response (27,140 +/- 6548 vs 35,670 +/- 10,245 mumol/L.240 min) in the NIDDM patients.

Aged↗

PubMed1990

The predictive capability of the glycaemic response to spaghetti in non-insulin dependent (NIDDM) and insulin dependent (IDDM) diabetic subjects.

To evaluate the predictive capability of the postprandial blood glucose response after consumption of a starch-rich meal, we compared the glycaemic effects of spaghetti (60 g) taken alone and with bolognese sauce (167 g). The study was carried out in both NIDDM (n = 6) and IDDM (n = 6) subjects. The latter had achieved normoglycaemia 120 min prior to the test meal by means of an artificial pancreas (Biostator) which provided constant insulinaemia during the observation period of 4 h. We found that the areas of blood glucose (above basal) were identical irrespective of whether spaghetti was taken alone or as part of a mixed meal in both NIDDM (484 +/- 154 mmol l-1 240 min-1 vs. 393 +/- 126 mmol l-1 240 min-1) and IDDM subjects (610 +/- 143 mmol l-1 240 min-1 vs. 770 +/- 135 mmol l-1 240 min-1). The insulin levels were identical in the IDDM diabetics. By contrast, the mixed meal caused a more marked insulinaemic response than spaghetti per se in the NIDDM subjects (3187 +/- 637 mU l-1 240 min-1 vs. 1940 +/- 235 mU l-1 240 min-1; P less than 0.05). In conclusion, the predictive capability of the glycaemic response to spaghetti was good in both IDDM and NIDDM diabetic subjects, at least under the conditions of the present study.

Blood Glucose↗