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L P Degen

Publications and source records attributed to L P Degen.

7 recordsLinked to original sources
PubMed2001

Blockade of GRP receptors inhibits gastric emptying and gallbladder contraction but accelerates small intestinal transit.

BACKGROUND & AIMS: This study was designed to characterize [D-F(5)Phe(6)D-Ala(11)]Bn(6-13)OMe (BIM26226) as a gastrin-releasing peptide (GRP)-preferring bombesin receptor antagonist and to determine whether GRP physiologically regulates gastrointestinal motility. Intravenous BIM26226 (5-500 microg. kg(-1). h(-1)) inhibits GRP-induced gallbladder contraction and plasma cholecystokinin (CCK) release in a dose-dependent fashion. METHODS: Gastric emptying and small bowel transit of a solid meal were quantified using scintigraphy. Meal-stimulated gallbladder contraction was measured by sonography in a 2-period crossover design. RESULTS: Intravenous BIM26226 potently inhibited gastric lag time (114 +/- 7 vs. 41 +/- 6 minutes [control]) and gastric emptying rate (0.11 +/- 0.02%/min vs. 0.26 +/- 0.04%/min [control]), whereas concomitant infusion of BIM26226 accelerated small bowel transit time (153 +/- 41 vs. 262 +/- 20 minutes [control]). A continuous liquid meal perfusion into the duodenum induced complete gallbladder contraction (t(50%), 35 +/- 4 minutes), which BIM26226 inhibited significantly (t(50%), 64 +/- 8 minutes). BIM26226 did not alter plasma CCK response, indicating that circulating CCK did not mediate these effects. CONCLUSIONS: These data show that BIM26226 is a potent antagonist of exogenous and endogenous GRP and suggest that GRP is a major physiologic regulator of gastric emptying, small bowel transit, and gallbladder contraction.

Adult↗
PubMed1997

Ileocecal segment transposition does not alter whole gut transit in humans.

OBJECTIVES: We have recently described a reservoir for rectal replacement after total mesorectal excision for rectal carcinoma. The ileocecal segment with its intact extrinsic nerve and blood supply is placed between the ascending colon and the anal canal. This reconstruction has been shown to provide good defecation quality and anorectal function. Whether gastric emptying and small as well as large bowel transit are affected by this transposition remains unclear. Our aim was to quantify whole gut transit in such patients and compare it with that of a matched group of controls. METHODS: Gastric emptying rates and small intestinal and colonic transit times were assessed scintigraphically in 12 patients aged 46 to 87 years with ileocecal reservoir reconstruction after total mesorectal excision and compared to a sex-matched group of asymptomatic healthy volunteers of similar age. Gastric emptying rates and small intestinal and colonic transit times were calculated as described previously. Data were compared using Wilcoxon's signed rank test for gastric emptying rates and small bowel transit or by analysis of variance for colonic transit; p < 0.05 was considered significant. RESULTS: Gastric time for half of the meal (T50) was 161 +/- 16 minutes for patients and 201 +/- 22 for the controls. Small bowel transit time was 150 +/- 15 minutes for patients and 177 +/- 22 for the controls. Geometric center at 6 hours was 1.53 +/- 0.13 for patients and 1.27 +/- 0.16 for the controls. Geometric center at 24 hours was 2.96 +/- 0.23 for patients and 2.57 +/- 0.25 for the controls. Data are mean +/- SEM. SUMMARY: Gastric emptying rates and small bowel transit and colonic transit times (expressed as geometric center at 6 and 24 hours) were similar in patients with ileocecal reservoir reconstruction and in a sex- and age-matched group of healthy controls. We conclude that the transposition of an ileocecal segment with intact extrinsic neurovascular supply between the sigmoid colon and the anal canal does not alter whole gut transit, not even in any of the presumably key regions.

Age Factors↗
PubMed1996

The ileocecal reservoir for rectal replacement in complicated radiation proctitis.

BACKGROUND/AIMS: Total rectal resection is the radical treatment method for radiation proctitis complications. Park's straight colo-anal reconstruction to replace the rectum often impairs anal continence, increases stool frequency, and causes imperative urgency. We developed and assessed a colo-anal reconstruction (ileocecal reservoir) after resection of radiation-damaged rectum. METHODS: An ileocecal segment was isolated on its lymphovascular pedicel, rotated counterclockwise, and reanastomosed at the dentate line. This provided a neorectal segment with intact intrinsic and extrinsic nerve and lymphovascular supply. We evaluated the safety, defecation quality, and anorectal function of this neorectum in two radiation-injured patients when compared with 15 patients after total mesorectal excision without radiation damage. RESULTS: No perioperative morbidity related to this technique was observed. Neorectal patients showed good defecation quality with maximal tolerable volumes, compliances, and anal manometry comparable with patients without radiation injury. CONCLUSIONS: This rectal replacement technique permits good defecation quality and excellent anorectal function.

Adult↗
PubMed1996

Ileocecal reservoir reconstruction with physiologic function after total mesorectal cancer excision.

BACKGROUND/AIMS: After proctectomy for low rectal cancer and straight coloanal reconstruction, the main causes for increased daily stool frequency, urgency, and incontinence are the limited capacity and distensibility of the anastomosed colic segment in the pelvis. The authors postulated that a pedunculated (preserving the nerve) ileocecal interpositional graft (cecum-reservoir) placed between the sigmoid colon and the anal canal would greatly reduce these inconveniences. METHODS: The authors evaluated the safety, defecation quality, and anorectal physiology of such a neorectum in 20 consecutive patients with rectal carcinoma between 5 and 10 cm above the anal verge who underwent total mesorectal excision. RESULTS: No perioperative morbidity related to the technique and no mortality was observed in these 20 patients. Six months after the operation, 16 patients showed excellent and 4 patients good defecation quality, with maximal tolerable volumes, compliance, and mean colonic transit times comparable to age- and gender-matched healthy volunteers. In addition, anal resting pressure was decreased, squeeze pressure was maintained, and the rectoanal inhibitory reflex remained positive in 80%. CONCLUSIONS: The cecum-reservoir as a neorectum, using an intact neurovascular colonic segment, is a safe technique, providing excellent defecation quality. It enables a nearly normal physiologic anorectal function, which is already seen 6 months postoperatively.

Aged↗
PubMed1996

How well does stool form reflect colonic transit?

BACKGROUND: Watery stools are equated with rapid and hard stools with slow intestinal transit; however, the relation between stool form and transit through specific regions of the gut is not clear cut. In addition, more information is needed on interindividual variability of these measurements. AIM: To examine the relations between stool form and gastric emptying, small bowel and colonic transit. METHODS: Regional gut transit was assessed scintigraphically and segmental colonic transit was also quantified by radio-opaque markers. On two occasions, 32 healthy volunteers (12 men, 20 women) were studied, women during the follicular and luteal phases of menstruation, men twice within a similar four week period. Diets were standardised and stool form was recorded on a seven point scale. RESULTS: Women had significant harder stools; hard stools were correlated significantly with slow transit and loose stools with fast transit through the colon. CONCLUSIONS: Stool form could not be related to gastric emptying or small bowel transit.

Colon↗
PubMed1996

Variability of gastrointestinal transit in healthy women and men.

BACKGROUND AND AIMS: Measurements of gastrointestinal transit are made in clinical and research gastroenterology, yet their intrinsic variability is not well characterised. In particular, an influence of hormones on transit has been proposed as the basis for gastrointestinal symptoms that vary with the menstrual cycle. Our aims were to quantify individual differences in transit during the menstrual cycle in healthy women and to compare these with the intrinsic variability in healthy men. METHODS: On two occasions, whole gut transit was assessed scintigraphically and colonic transit quantified by radio-opaque markers. Thirty two healthy volunteers (12 women, 20 men) were studied, women during the follicular and luteal phases, men twice within a similar four week period. Diets and exercise were standardised prior to and during both studies. RESULTS: Colonic transit was significantly faster in men, and postlag gastric emptying was also more rapid; other indices of regional transit were not different between the sexes. Total colonic transit time was equally well reflected by the scintigraphic and radio-opaque marker methods. Important intraindividual differences were noted in both sexes. The variances in our samples predicted an 80% chance of detecting (with 95% confidence) a mean effect of menstrual hormones on transit that was in the same range as the intrinsic variation in men. CONCLUSIONS: Colonic transit was faster in men than in women. Although group means in the two studies were almost identical, single assessments of transit in subjects sometimes exhibited considerable variability, implying broad biological variations. Given this intrinsic variability, the influence of menstrual hormones on gastrointestinal transit must be small and of doubtful clinical significance.

Adult↗