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J L Madsen

Publications and source records attributed to J L Madsen.

At least 19 recordsLinked to original sources
PubMed2001

Gastrointestinal mean transit times in young and middle-aged healthy subjects.

To investigate the effects of age and gender on gastric, small intestinal and colonic mean transit times, a study was conducted in 32 healthy volunteers: eight young women (22-30 years), eight young men (20-28 years), eight middle-aged women (43-51 years) and eight middle-aged men (38-53 years). After ingestion of a meal containing 111Indium-labelled water and 99mTechnetium-labelled omelette imaging of the abdomen was performed at intervals of 30 min until all radioactivity was located in the colon and henceforth at intervals of 24 h until all radioactivity had cleared from the colon. Gastric, small intestinal and colonic mean transit times were calculated. The gastric, small intestinal and colonic mean transit times were significantly longer in women. Ageing was shown to accelerate the gastric and small intestinal transit significantly. In the group of men the colonic mean transit time was unaffected by age, but middle-aged women had a significantly slower colonic transit than young women. We therefore conclude that both age and gender have to be considered when reference values for gastric, small intestinal and colonic mean transit times have to be established.

Adult↗
PubMed2001

Glucagon-like peptide 2 improves nutrient absorption and nutritional status in short-bowel patients with no colon.

BACKGROUND & AIMS: Glucagon-like peptide 2 (GLP-2) is intestinotrophic, antisecretory, and transit-modulating in rodents, and it is mainly secreted from the intestinal mucosa of the terminal ileum and colon after food ingestion. We assessed the effect of GLP-2 on the gastrointestinal function in patients without a terminal ileum and colon who have functional short-bowel syndrome with severe malabsorption of wet weight (>1.5 kg/day) and energy (>2.3 MJ/day) and no postprandial secretion of GLP-2. METHODS: Balance studies were performed before and after treatment with GLP-2, 400 microg subcutaneously twice a day for 35 days, in 8 patients (4-17 years from last bowel resection; 6 with Crohn's disease). Four patients received home parenteral nutrition (mean residual jejunum, 83 cm), and 4 did not (mean ileum resection, 106 cm). Biopsy specimens were taken from jejunal/ileal stomas, transit was measured by scintigraphy, and body composition was measured by dual-energy x-ray absorptiometry. RESULTS: Treatment with GLP-2 improved the intestinal absorption of energy 3.5% +/- 4.0% (mean +/- SD) from 49.9% to 53.4% (P = 0.04), wet weight 11% +/- 12% from 25% to 36% (P = 0.04), and nitrogen 4.7% +/- 5.4% from 47.4% to 52.1% (P = 0.04). Body weight increased 1.2 +/- 1.0 kg (P = 0.01), lean body mass increased 2.9 +/- 1.9 kg (P = 0.004), fat mass decreased 1.8 +/- 1.3 kg (P = 0.007), and 24-hour urine creatinine excretion increased (P = 0.02). The time to 50% gastric emptying of solids increased 30 +/- 16 minutes from 89 to 119 minutes (P < 0.05). Small bowel transit time was not changed. Crypt depth and villus height were increased in 5 and 6 patients, respectively. CONCLUSIONS: Treatment with GLP-2 improves intestinal absorption and nutritional status in short-bowel patients with impaired postprandial GLP-2 secretion in whom the terminal ileum and the colon have been resected.

Adult↗
PubMed2000

Effect of obesity and major weight reduction on gastric emptying.

BACKGROUND: An enhanced gastric emptying rate might reduce the satiating effect of food and thereby promote obesity. Gastric emptying rate has previously been compared between obese and lean subjects with conflicting outcome. OBJECTIVE: Comparison of gastric emptying rate in lean and obese subjects before and after a major weight reduction. DESIGN: The study was designed as a case-control study comparing obese and lean subjects and a subsequent comparison of obese subjects before and after a dietary induced major weight reduction. METHOD: Gastric emptying rate following a solid test meal was estimated scintigraphically for 3 h using the left anterior oblique projection. SUBJECTS: Nineteen non-diabetic obese (mean BMI=38.7 kg/m2) and 12 lean (mean BMI=23.1 kg/m2) males matched for age and height. All obese subjects were re-examined after a mean weight loss of 18.8 kg (95% CI, 14.4-23.2) achieved by 16 weeks of dietary intervention followed by 8 weeks of weight stability. RESULTS: When comparing obese and lean subjects no differences were seen in overall 3 h emptying rate (30.3% per hour vs 30.5% per hour). However, a trend towards a higher percentage gastric emptying during the initial 30 min was seen in the obese when compared to lean subjects (24.0% vs 17.8% of the test meal; P=0.08). Weight loss was associated with a reduction in percentage gastric emptying during the initial 30 min (from 24.0% to 18.3% of the test-meal; P<0. 02), whereas the overall 3 h emptying rate was unaffected (30.3% vs 30.9% per hour). Neither initial or overall emptying rate differed between reduced-obese and lean subjects. CONCLUSION: Overall 3 h gastric emptying rate was similar in obese and normal weight males, and unaffected by a major weight loss. However, percentage gastric emptying during the initial 30 min for a solid meal appeared to be increased in obese males and was normalized after a major weight reduction.

Adolescent↗
PubMed2000

Simplified scintigraphic methods for measuring gastrointestinal transit times.

To investigate whether simple transit measurements based on scintigraphy performed only 0, 2, 4 and 24 h after intake of a radiolabelled meal can be used to predict the mean transit time values for the stomach, the small intestine, and the colon, a study was conducted in 16 healthy volunteers. After ingestion of a meal containing 111indium-labelled water and 99mtechnetium-labelled omelette, imaging was performed at intervals of 30 min until all radioactivity was located in the colon and henceforth at intervals of 24 h until all radioactivity had cleared from the colon. Gastric, small intestinal and colonic mean transit times were calculated for both markers and compared with fractional gastric emptying at 2 h, fractional colonic filling at 4 h, and geometric centre of colonic content at 24 h, respectively. Highly significant correlations were found between gastric mean transit time and fractional gastric emptying at 2 h (111In: r=0.95, P<0.00001; 99mTc: r=0.96, P<0.00001), between small intestinal mean transit time and fractional colonic filling at 4 h (111In: r=-0.97, P<0.00001; 99mTc: r=-0.89, P<0. 00001), and between colonic mean transit time and geometric centre of colonic content at 24 h (111In: r=- 0.88, P<0.00001). We therefore conclude that reliable regional gastrointestinal transit times can be estimated from scintigraphic images taken 0, 2, 4 and 24 h after intake of radiolabelled markers.

Adult↗
PubMed2000

Scintigraphic method for evaluating reductions in local blood volumes in human extremities.

We introduce a new method for evaluating reductions in local blood volumes in extremities, based on the combined use of autologue injection of 99mTc-radiolabelled erythrocytes and clamping of the limb blood flow by the use of a tourniquet. Twenty-two healthy male volunteers participated in the experiment. Evaluation of one versus two scintigraphic projections, trials for assessment of the reproducibility, a comparison of the scintigraphic method with a water-plethysmographic method and registration of the fractional reduction in blood volume caused by exsanguination as a result of simple elevation were carried out. No significant differences between results obtained by the use of one or two scintigraphic projections were found. The between-subject coefficient of variation was 14% in the lower limb experiment and 11% in the upper limb experiment. The within-subject coefficient of variation was 6% in the lower limb experiment and 6% in the upper limb experiment. We found a significant relation (r = 0.42, p = 0.018) between the results obtained by the scintigraphic method and the plethysmographic method. In fractions, a mean reduction in blood volume of 0.49+0.14 (2 SD) was found after 1 min of elevation of the lower limb and a mean reduction of 0.45+/-0.10 (2 SD) after half a minute of elevation of the upper limb. We conclude that the method is precise and can be used in investigating physiologic and pathophysiologic mechanisms in relation to blood volumes of limbs not subject to research previously.

Adult↗
PubMed2000

Gastrointestinal motor function in patients with portal hypertension.

BACKGROUND: Existing data on gastric emptying and small-intestinal transit rates in portal-hypertensive patients are scarce and contradictory, and so far, the motor function of the colon has not been assessed in these patients. In this study we evaluated the propulsive effect of all main segments of the gastrointestinal tract in patients with well-characterized portal hypertension. METHODS: Eight patients with a postsinusoidal hepatic pressure gradient of at least 13 mmHg and eight age- and sex-matched healthy controls participated in the study. Gastric emptying, small-intestinal transit, and colonic transit rates were evaluated in all subjects by means of a gamma camera technique. The technique was also used to measure the frequency of antral contractions. RESULTS: No difference was observed in gastric mean emptying time or small-intestinal mean transit time of liquid and solid markers between patients and controls. After 24 h, however, the geometric center of the liquid marker had a more caudal localization in the colon of the patient group than in the controls (P = 0.04); that is, the patients had a faster colonic transit. No difference was found in the frequency of antral contractions 45 min after the test meal between patients and controls. CONCLUSIONS: These data suggest that the colonic transit is often accelerated in patients with portal hypertension, whereas the motor function of the stomach and the small intestine is unaffected.

Adult↗
PubMed2000

A simplified method for processing dynamic images of gastric antrum.

By means of a dynamic acquisition protocol and a Fourier transform algorithm the scintigraphic technique can be used to assess gastric antral motility. In previous approaches, however, the definition of a region of interest (ROI) that gives rise to an unequivocal result of the analysis of the corresponding time-activity curve might be crucial. To overcome this problem we evaluated a new technique based on a fixed box-ROI and a simple weighting principle. Eight healthy volunteers ingested a meal that contained a 99Tcm-stannous colloid labelled omelette. Gastric emptying was assessed from static images taken at 30-mm intervals for 2 h. Anterior dynamic frames of 1 s each, which were acquired for 5 mm after each static acquisition, were used to determine the frequency of antral contractions. In order to allow for precise outlining of the antrum, each set of dynamic images was at first reframed into a single 5-mm image. The same ROI (20 pixels vertical, 15 pixels horizontal) was then positioned over the distal portion of the antrum on each reframed image. On each 1-s frame the obtained counts in each of the 15 columns of 20 pixels were summed. Then the localization of the geometric centre of radioactivity in the 15 columns was determined. On the assumption that the horizontal oscillations of the geometric centre of radioactivity in the ROI reflected the contractile activity of the antrum, the frequency of these contractions was calculated by fast Fourier transform analysis of the obtained time versus geometric centre curve. In all subjects, our technique gave unequivocal frequencies of antral contractions at each time point. Statistical analysis did not reveal any intraindividual variation in this frequency during gastric emptying. We believe that the simplified scintigraphic method is an advantageous alternative for assessing the frequency of antral contractions.

Adult↗
PubMed2000

Magnetic resonance imaging, radiography, and scintigraphy of the finger joints: one year follow up of patients with early arthritis. The TIRA Group.

OBJECTIVES: To evaluate synovial membrane hypertrophy, tenosynovitis, and erosion development of the 2nd to 5th metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints by magnetic resonance imaging in a group of patients with rheumatoid arthritis (RA) or suspected RA followed up for one year. Additionally, to compare the results with radiography, bone scintigraphy, and clinical findings. PATIENTS AND METHODS: Fifty five patients were examined at baseline, of whom 34 were followed up for one year. Twenty one patients already fulfilled the American College of Rheumatology (ACR) criteria for RA at baseline, five fulfilled the criteria only after one year's follow up, whereas eight maintained the original diagnosis of early unclassified polyarthritis. The following MRI variables were assessed at baseline and one year: synovial membrane hypertrophy score, number of erosions, and tenosynovitis score. RESULTS: MRI detected progression of erosions earlier and more often than did radiography of the same joints; at baseline the MRI to radiography ratio was 28:4. Erosions were exclusively found in patients with RA at baseline or fulfilling the ACR criteria at one year. At one year follow up, scores of MR synovial membrane hypertrophy, tenosynovitis, and scintigraphic tracer accumulation had not changed significantly from baseline; in contrast, swollen and tender joint counts had declined significantly (p<0.05). CONCLUSIONS: MRI detected more erosions than radiography. MR synovial membrane hypertrophy and scintigraphy scores did not parallel the changes seen over time in clinically assessed swollen and tender joint counts. Although joint disease activity may be assessed as quiescent by conventional clinical methods, a more detailed evaluation by MRI may show that a pathological condition is still present within the synovium.

Adult↗
PubMed1999

A deconvolution technique for processing small intestinal transit data.

The deconvolution technique can be used to compute small intestinal impulse response curves from scintigraphic data. Previously suggested approaches, however, are sensitive to noise from the data. We investigated whether deconvolution based on a new simple iterative convolving technique can be recommended. Eight healthy volunteers ingested a meal that contained indium-111 diethylene triamine penta-acetic acid labelled water and technetium-99m stannous colloid labelled omelette. Imaging was performed at 30-min intervals until all radioactivity was located in the colon. A Fermi function=(1+e-alphabeta)/(1+e(t-alpha)beta) was chosen to characterize the small intestinal impulse response function. By changing only two parameters, alpha and beta, it is possible to obtain configurations from nearly a square function to nearly a monoexponential function. Small intestinal input function was obtained from the gastric emptying curve and convolved with the Fermi function. The sum of least squares was used to find alpha and beta yielding the best fit of the convolved curve to the observed small intestinal time-activity curve. Finally, a small intestinal mean transit time was calculated from the Fermi function referred to. In all cases, we found an excellent fit of the convolved curve to the observed small intestinal time-activity curve, that is the Fermi function reflected the small intestinal impulse response curve. Small intestinal mean transit time of liquid marker (median 2.02 h) was significantly shorter than that of solid marker (median 2.99 h; P<0.02). The iterative convolving technique seems to be an attractive alternative to ordinary approaches for the processing of small intestinal transit data.

Adult↗
PubMed1996

Gallbladder emptying and cholecystokinin response to fish oil and trioleate ingestion.

The aim of the present study was to compare gallbladder emptying, gastric emptying and release of cholecystokinin (CCK), gastrin and secretin after intragastric administration of fish oil and trioleate. After intravenous injection of 99mTc-HIDA, 30 ml of a lipid labelled with 111In was administered through a gastric tube. Using dual scintigraphy with two markers, gallbladder and gastric emptying were measured simultaneously for 120 min. Plasma concentrations of gastrin, secretin and CCK, were determined throughout the period. The emptying of the gallbladder was reduced by 27% and the release of CCK by 85% after fish oil as compared with trioleate. Gastric emptying as well as the release of gastrin and secretin were similar after the two types of fat. The results suggest that the reduced gallbladder emptying after fish oil may be due to a smaller release of CCK.

Adult↗
PubMed1996

Relationship between small-intestinal transit rate and intestinal absorption of (14)C-labelled mannitol and (51)Cr-labelled ethylenediaminetetraacetic acid in healthy subjects.

BACKGROUND: Although the small-intestinal transit rate is generally considered to influence the urinary excretion of markers of intestinal permeability, no study has until now formally addressed the importance of this influence in humans. METHODS: Ten healthy subjects ingested a test solution containing (99m)Tc-labelled diethylenetriaminepentaacetic acid ((99)mTc-DTPA), (14)C-labelled mannitol ((14)C-mannitol), and (51)Cr-labelled ethylenediaminetetraacetic acid ((51)Cr-EDTA). After ingestion, the small-intestinal transit rate of (99)mTc-DTPA was measured with the gamma camera technique. Urine was collected for time periods of 0-2 h, 2-4 h, and 4-6 h to measure the excretion of absorbed (14)C-mannitol and (51)Cr-EDTA. Moreover, the distribution volume and plasma clearance of (14)C-mannitol and (51)Cr-EDTA were determined in each subject. RESULTS: A positive correlation was found between mean small-intestinal transit time and 0- to 6-h urinary excretion of (14)C-mannitol. The study did not show any correlation between small-intestinal transit rate and 0- to 6-h urinary excretion of (51)Cr-EDTA. Urinary excretion of neither (14)C-mannitol nor (51)Cr-EDTA was affected by distribution volume or urine volume. A positive correlation was observed between plasma clearance and 0- to 6-h urinary excretion of (14)C-mannitol, whereas plasma clearance did not influence the urinary excretion of (51)Cr-EDTA. CONCLUSIONS: Small-intestinal transit rate seems to have a significant effect on 0- to 6-h urinary excretion of (14)C-mannitol, whereas small intestinal transit rate does not influence the timed urinary excretion of (51)Cr-EDTA.

Adult↗
PubMed1992

Gastrointestinal transit times of radiolabeled meal in progressive systemic sclerosis.

Gastrointestinal transit times were measured in 12 patients with progressive systemic sclerosis. The CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) was found in all patients. None of the patients reported complaints referable to specific gastric, small intestinal, or colonic involvement. The patient group had an increased mean gastric emptying time of 99mTc-labeled cellulose fiber when compared with 16 healthy controls [1.17 (0.89-1.38) hr [median (range)] vs 0.84 (0.56-1.88) hr; P less than 0.02], whereas mean gastric emptying time of 2- to 3-mm 111In-labeled plastic particles was unaffected [1.86 (0.99-2.74) hr vs 1.50 (0.92-2.51) hr; NS]. No difference was observed in mean small intestinal transit time of cellulose fiber [4.33 (0.50-7.04) hr vs 3.74 (2.09-7.59) hr; NS] or plastic particles [4.21 (2.00-6.25) hr vs 3.53 (1.50-6.70) hr; NS] between patients and controls. The patient group had an increased mean colonic transit time of plastic particles [47 (24-116) hr vs 29 (18-46) hr; P less than 0.01]. These findings suggest that asymptomatic delay in gastric emptying and colonic transit is frequent in patients with progressive systemic sclerosis.

Adult↗
PubMed1992

Effects of gender, age, and body mass index on gastrointestinal transit times.

This study aimed to assess separately the effects of gender, age, and body mass index on gastric emptying, small intestinal transit, and colonic transit times of a meal containing 99mTc-labeled cellulose fiber and 2- to 3-mm 111In-labeled plastic particles. Seventeen healthy young subjects (nine men; eight women; age 21-27 years; body mass index 18.4-25.1 kg/m2) and 16 healthy older subjects (eight men; eight women; age 55-74 years; body mass index 19.8-36.0 kg/m2) were studied. All transit variables were unaffected by gender. The older subjects had a slower mean colonic transit time of radiolabeled plastic particles than the young subjects (P < 0.05). Age did not affect mean gastric emptying or mean small intestinal transit times of the radiolabeled markers. An inverse association was found between body mass index and mean gastric emptying time of radiolabeled cellulose fiber (P < 0.02). Body mass index had no influence on other transit variables. The study revealed a considerable intersubject and a somewhat smaller intrasubject variability in mean gastric emptying, mean small intestinal, and mean colonic transit times.

Adult↗
PubMed1991

Scintigraphic determination of gastrointestinal transit times. A comparison with breath hydrogen and radiologic methods.

A scintigraphic method for determination of gastrointestinal transit times was compared with the breath hydrogen test and a multiple-bolus, single-radiograph technique. A close temporal association was found between the caecal appearance of radioactivity and the onset of breath hydrogen excretion in eight healthy subjects. Neither mean small-intestinal nor mean orocaecal transit times of the radiolabelled marker were correlated with the magnitude of hydrogen peak, hydrogen peak time, or the area under hydrogen curve. No correlation was noted between whole-gut transit time of the radiolabelled marker and mean whole-gut transit time calculated from a 6-day administration of the radiopaque marker in 16 healthy subjects. The stool weight was inversely correlated with the mean colonic (r = -0.46, p = 0.009) and the mean whole-gut (r = -0.45, p = 0.011) transit times of the radiolabelled marker. In conclusion, inadequate delineation of the caecal region seems to be an unimportant drawback of the scintigraphic measurements, whereas day-to-day variation in gastrointestinal transit rates may influence the reliability of the assessments. Probably, quantitative transit data cannot be obtained from the breath hydrogen concentration profiles.

Adult↗
PubMed1990

Effects of cisapride on gastrointestinal transit in healthy humans.

It was the aim of this study to assess the effects of cisapride on gastrointestinal transit of solids in healthy humans. Twelve men received cisapride 10 mg or placebo orally four times a day in random, double-blind, crossover fashion. Transit measurements were performed with a new gamma camera technique. Cisapride reduced mean gastric emptying time of 99mTc-labeled cellulose fiber [0.77 (0.69-1.12) hr [median (range)] vs 0.98 (0.63-1.95) hr; P less than 0.05] and 1- to 2-mm 111In-labeled plastic particles [1.08 (0.50-1.42) hr vs 1.69 (0.59-3.03) hr; P less than 0.01]. Cisapride also decreased mean small intestinal transit time of cellulose fiber [2.11 (0.80-5.08) hr vs 2.82 (0.78-7.12) hr; P less than 0.05] and plastic particles [2.06 (1.13-5.13) hr vs 2.64 (1.18-7.04) hr; P less than 0.05]. However, cisapride increased mean large intestinal transit time of plastic particles [31 (13-75) hr vs 23 (12-36) hr; P less than 0.05]. In conclusion, oral cisapride 10 mg four times a day accelerates gastric emptying and small intestinal transit whereas this dose of cisapride seems to delay large intestinal transit of solids in healthy humans.

Adult↗
PubMed1990

Tc-99m-MDP scintigraphy not informative in painful total hip arthroplasty.

In 61 painful cemented total hip arthroplasties the diagnostic specificity was 0.7 for plain radiography and 0.46 for scintigraphy. The diagnostic sensitivity was 0.97 for radiography and 0.77 for scintigraphy. False negative radiology occurred in 0.05 and false positive in 0.23. False negative scintigraphy was encountered in 0.27 and false positive in 0.49. Seven of thirty-nine hips were operatively explored because of false positive scintigraphy. In conclusion, Tc-99m-MDP scintigraphy could not used as a complementary diagnostic measure in our hands.

Adult↗