PubMed Health⌕ Search

Biomedical subjects

J L Madsen

Publications and source records attributed to J L Madsen.

At least 19 recordsLinked to original sources
PubMed2003

Colorectal transport during defecation in patients with lesions of the sacral spinal cord.

Normal defecation involves reflexes between the colorectum and sacral spinal cord. Lesions of the conus medullaris or cauda equina interrupt such reflex arches and cause constipation. The aim of the study was to compare colorectal transport during defecation in patients with sacral spinal cord lesions and healthy volunteers. Ten patients with sacral spinal cord lesions (six men and four women, age 21-57 y, median = 36) and 16 healthy volunteers (10 men and six women, age 22-42 y, median = 30) took one or two doses of 111In-labelled polystyrene pellets perorally to mark colorectal contents. Abdominal scintigraphy was performed before and after defecation. Total colorectal emptying and segmental antegrade or retrograde transport was computed. Median colorectal emptying during normal defecation was 81% of the rectosigmoid (range: 53% of the rectosigmoid to complete emptying of the rectosigmoid and 40% of the descending colon) in healthy volunteers and 27% of the rectosigmoid (range: 0-44% of the rectosigmoid) in patients with conal/cauda equina lesions (P < 0.001). Median antegrade transport was 82% (control group) vs 27% (patients) of the rectosigmoid (P < 0.001), 38% vs 4% of the descending colon (P < 0.02), 13% vs 1% of the transverse colon (P = 0.28), and 4% vs 2% of the caecum/ascending colon (P = 0.76). It is concluded that damage to reflex arches between the colorectum and the sacral spinal cord significantly reduces emptying of the rectosigmoid and descending colon during defecation.

Adult↗
PubMed2003

Colorectal transport in normal defaecation.

OBJECTIVE: Colorectal luminal transport during defaecation can be assessed by means of scintigraphy. However, normal values remain to be established and inter- and intra-subjective variation is unknown. The aim of the study was to describe colorectal transport during normal defaecation by means of a new method for colorectal scintigraphy and to determine inter- and intrasubjective variation. METHODS: Thirty healthy volunteers (18 men and 12 women, age 22-46 years; median 31) took 2 MBq 111In on two consecutive days (days 0 and 1). On days 1 and 2 an abdominal scintigraphy was done before and after defaecation. Changes in colorectal contents were computed in two ways: firstly, assuming ordered evacuation, the extent of colorectal emptying was computed; secondly, antegrade and retrograde transport within the colorectum was computed for each colorectal segment. RESULTS: Median colorectal emptying during normal defaecation was 99% of the rectosigmoid (range: 60% of the rectosigmoid to complete emptying of the rectosigmoid, descending colon, transverse colon and 19% of the caecum/ascending colon). There was no difference between men (median 99% of the rectosigmoid) and women (98% of the rectosigmoid). Day to day variation was large (dispersion=52%) with a trend towards larger defaecation on day 2 than on day 1 (P = 0.09). Large antegrade and retrograde movements of colorectal contents were observed within the colorectum during defaecation. Antegrade transport involved the rectosigmoid (median 99%), the descending colon (median 53%), the transverse colon (median 46%), and the caecum/ascending colon (median 11%). Retrograde transport was mainly from the transverse colon and the descending colon. Colorectal emptying was significantly correlated to the subjective description (P < 0.01) but not to total gastrointestinal or segmental colorectal transit times determined by means of radioopaque markers. CONCLUSIONS: Colorectal scintigraphy before and after defaecation provides detailed information about colorectal emptying and intracolonic antegrade or retrograde transport during defaecation. Inter- and intraindividual variations are large and antegrade and retrograde transport within the colorectum is common.

Adult↗
PubMed2002

Short-term administration of glucagon-like peptide-2. Effects on bone mineral density and markers of bone turnover in short-bowel patients with no colon.

BACKGROUND: Glucagon-like peptide 2 (GLP-2) is a newly discovered intestinotrophic hormone. We have recently reported that a 5-week GLP-2 treatment improved the intestinal absorptive capacity of short-bowel patients with no colon. Additionally, GLP-2 treatment was associated with changes in body composition that included a significant increase in total body bone mass. This article describes the effect of GLP-2 on spinal and hip bone mineral density (BMD) and biochemical markers of bone turnover in these patients. METHODS: In an open-labelled pilot study, eight short-bowel patients (3M, 5F; mean age 49 years) with small-bowel resection and no colon received 400 microg s.c. of GLP-2 twice daily for 5 weeks. Four received home parenteral nutrition (mean length of residual jejunum 83 cm) and 4 did not (mean length of ileum resected 106 cm). The outcome measures were the mean percent change from baseline in spinal and hip BMD measured by dual-energy X-ray absorptiometry, changes in four biochemical markers of bone-turnover, PTH, 25-hydroxy vitamin-D, and the intestinal absorption of calcium. RESULTS: Mean +/- s(x) (SEM) percent changes in spinal and hip BMD were 1.1+/-0.4% (P < 0.05) and 1.9+/-0.8% (P = 0.06), respectively. The intestinal calcium absorption increased by 2.7% (P = 0.87). Serum ionized calcium increased in 5/8 patients with a concomitant decrease in serum PTH values. Three of the four markers of bone turnover decreased. CONCLUSION: A 5-week GLP-2 administration significantly increased spinal BMD in short-bowel patients with no colon. The mechanism by which GLP-2 affects bone metabolism remains unclear, but may be related to an increased mineralization of bone resulting from an improved intestinal calcium absorption.

Absorptiometry, Photon↗
PubMed2002

Exsanguination of the upper limb in healthy young volunteers.

Using a scintigraphic technique based on an autologous injection of 99mTc-labelled erythrocytes, we have evaluated the efficiency of different exsanguination procedures in the upper limb of ten healthy male volunteers. The methods were elevation alone, the use of the Esmarch bandage or a gauze bandage, the Pomidor roll-cuff, the squeeze method and the Urias bag. The various procedures gave the following median percentage reductions of blood volumes: elevation for 5 seconds 44%, 15 seconds 45%, 30 seconds 46%, 60 seconds 46% and 4 minutes 42%, the Esmarch bandage 69%, a gauze bandage 63%, the Pomidor roll-cuff 66%, the squeeze method 53%, and the Urias bag 57%. With regard to elevation alone no significant differences were found. All the external methods were significantly more effective than elevation alone. Overall, the squeeze method was found to be the best method of exsanguination before inflation of a tourniquet, because it is effective, fast, practical and inexpensive.

Adult↗
PubMed2001

Normal gastrointestinal transit after colonic resection using epidural analgesia, enforced oral nutrition and laxative.

BACKGROUND: Postoperative ileus usually lasts for 2-5 days after colonic surgery and may contribute to discomfort and pulmonary complications. With multimodal rehabilitation (epidural analgesia, early oral nutrition and mobilization, and laxative) defaecation occurs 1-2 days after colonic surgery. The aim of this study was to assess the transit rate of the entire gastrointestinal tract after colonic resection with multimodal rehabilitation. METHODS: Gastrointestinal motility was assessed by means of a scintigraphic method in 12 patients undergoing open colonic resection with multimodal rehabilitation and in 12 matched healthy volunteers. After intragastric or oral administration of 4 MBq 111In-labelled diethylenetriamine penta-acetic acid, images of the abdomen were taken at 24 and 48 h with a double-headed gamma camera. RESULTS: Patient and volunteer demographics were similar. The first defaecation occurred a median of 1 day after operation in the patients. Some 57 per cent of the tracer was excreted in faeces of patients and 53 per cent in faeces of volunteers (P > 0.05) within 48 h, indicating rapid recovery of the entire gastrointestinal motility after colonic resection with multimodal rehabilitation. CONCLUSION: This study documents early normalization of the entire gastrointestinal motility assessed by an 111In scintigraphic method in patients undergoing open colonic resection with a multimodal rehabilitation programme.

Aged↗
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↗