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1.
The present study was undertaken to determine whether alterations in the gallbladder sensitivity to cholecystokinin (CCK), apart from a reduced endogenous CCK secretion, contribute to the abnormally decreased postprandial gallbladder contraction in patients with coeliac disease. Gallbladder emptying, measured by cholescintigraphy, and plasma CCK levels, measured by radioimmunoassay, were studied during infusion of graded doses of the CCK analog cerulein in six coeliac patients with subtotal villous atrophy, six coeliac patients on a gluten-free diet with normal villous architecture, and nine control subjects. Both in the patients and in the controls infusion of stepwise increasing doses of cerulein, in the range of 1-16 ng.kg-1.h-1, induced dose-related changes in plasma CCK-like immunoreactivity (CCK-LI) (r = 0.99; p less than 0.001) and gallbladder emptying (r greater than 0.97; p less than 0.01-p less than 0.001). Plasma CCK-LI and gallbladder responses were not significantly different among untreated coeliac patients, treated coeliac patients, and controls. Gallbladder sensitivity to cerulein in untreated and treated coeliac patients was not significantly different from that in controls. It is concluded that the abnormally decreased gallbladder contraction in coeliac patients is the result of a reduced endogenous CCK secretion and not of a lack of end-organ responsiveness to CCK.  相似文献   
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OBJECTIVE: The effect of a cyclic versus a continuous enteral feeding protocol on postoperative delayed gastric emptying, start of normal diet, and hospital stay was assessed in patients undergoing pylorus-preserving pancreatoduodenectomy (PPPD). SUMMARY BACKGROUND DATA: Delayed gastric emptying occurs in approximately 30% of patients after PPPD and causes prolonged hospital stay. Enteral nutrition through a catheter jejunostomy is used to provide postoperative nutritional support. Enteral infusion of fats and proteins activates neurohumoral feedback mechanisms and therefore can potentially impair gastric emptying and prolong postoperative gastroparesis. METHODS: From September 1995 to December 1996, 72 consecutive patients underwent PPPD at the Academic Medical Center, Amsterdam. Fifty-seven patients were included and randomized for either continuous (CON) jejunal nutrition (0-24 hr; 1500 kCal/24 hr) or cyclic (CYC) enteral nutrition (6-24 hr; 1125 kCal/18 hr). Both groups had an equal caloric load of 1 kCal/min. The following parameters were assessed: days of nasogastric intubation, days of enteral nutrition, days until normal diet was tolerated orally, and hospital stay. On postoperative day 10, plasma cholecystokinin (CCK) levels were measured during both feeding protocols. RESULTS: Nasogastric intubation was 9.1 days in the CON group (n = 30) and 6.7 days in the CYC group (n = 27) (not statistically significant). First day of normal diet was earlier for the CYC group (15.7 vs. 12.2 days, p < 0.05). Hospital stay was shorter in the CYC group (21.4 vs. 17.5 days, p < 0.05). CCK levels were lower in CYC patients, before and after feeding, compared with CON patients (p < 0.05). CONCLUSIONS: Cyclic enteral feeding after PPPD is associated with a shorter period of enteral nutrition, a faster return to a normal diet, and a shorter hospital stay. Continuously high CCK levels could be a cause of prolonged time until normal diet is tolerated in patients on continuous enteral nutrition. Cyclic enteral nutrition is therefore the feeding regimen of choice in patients after PPPD.  相似文献   
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During total parenteral nutrition (TPN) gallbladder bile stasis and hypomotility have been well documented. Little is known, however, about the effect of the separate components of TPN on gallbladder motor function. Inasmuch as fat, administered intraduodenally, is a potent stimulus of cholecystokinin (CCK) secretion and gallbladder contraction we have investigated whether intravenous (IV) fat affects gallbladder motility. Six healthy volunteers were studied on two separate occasions, during infusion of Intralipid 10%, 200 mL/h or saline infusion (control) for 3 hours, to evaluate the effect of IV infusion of fat on (1) plasma CCK concentration and gallbladder volume and (2) CCK-induced gallbladder emptying. Intravenous infusion of Intralipid resulted in significant increases in serum triglycerides from 0.9 +/- 0.1 to 5.1 +/- 1.3 mmol/L (at 90 min). During fat infusion no significant changes in plasma CCK and gallbladder volume were noted when compared with basal values or to the control experiment. During IV fat, concomitant infusion of 0.25, 0.5, and 1.0 Ivy dog unit (IDU) per kilogram per hour of CCK-33 resulted in a significant reduction in gallbladder volume from 26 +/- 6 cm3 (basal) to 15 +/- 4 cm3 (p less than .05), 6 +/- 2 cm3 (p less than .05) and 2.5 +/- 1 cm3 (p less than .05), respectively. No significant differences in CCK-induced gallbladder emptying were observed between IV fat and saline infusion (control). It is concluded that, in contrast to intraduodenal fat, IV infusion of fat does not affect (1) basal plasma CCK and gallbladder volume and (2) CCK-induced gallbladder contraction.  相似文献   
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Effect of laparoscopic partial fundoplication on reflux mechanisms   总被引:1,自引:0,他引:1  
OBJECTIVES: Transient lower esophageal sphincter relaxations (TLESRs) are the main mechanism causing gastroesophageal reflux. Since 1994 we have performed laparoscopic partial instead of complete fundoplication as standard surgical treatment for therapy resistant reflux disease to minimize postoperative dysphagia. To better understand the management of gastroesophageal reflux, we conducted a prospective study of the effects of laparoscopic partial fundoplication on TLESRs and other reflux mechanisms. METHODS: From 1994 to 1999, 65 patients underwent laparoscopic partial fundoplication (180-200 degrees) and 28 of these patients (16 female, 12 male, mean age 43 +/- 2 yr [range, 26-66 yr]) agreed to participate in this prospective study on reflux mechanisms. Before and 6 months after surgery, all patients were evaluated by simultaneous recording of pH and lower esophageal sphincter characteristics, using sleeve manometry. RESULTS: After partial fundoplication basal LES pressure increased significantly (p < 0.05), from 14.3 +/- 1.2 mm Hg to 17.8 +/- 1 mm Hg. Partial fundoplication significantly (p < 0.05) decreased the number of TLESRs, from 3.4 +/- 0.8 to 1.6 +/- 0.3 per hour in the fasting period, and from 4.7 +/- 0.5 to 1.9 +/- 0.3 per hour postprandially. The percentage of TLESRs associated with reflux also decreased significantly (p < 0.05), from 45 +/- 7% to 27 +/- 6% after operation. The number of reflux episodes decreased significantly (p < 0.05), from 4.1 +/- 0.7 to 1.3 +/- 0.3 per hour postoperatively. The majority of these episodes were associated with TLESRs: 57% and 46%, pre- and postoperatively, respectively. CONCLUSIONS: Laparoscopic partial fundoplication significantly increased fasting and postprandial LES pressure and significantly decreased TLESR frequency. This resulted in a significant reduction in esophageal acid exposure, with preservation of postprandial LES characteristics.  相似文献   
6.
BACKGROUND: Patients with Crohn disease (CD) have an increased risk of developing gallstones. Among other factors, gallbladder motility may have a role in the pathogenesis of gallstone formation. We have evaluated whether gallbladder motor function is affected in Crohn disease with special emphasis on the influence of disease localization and previous bowel resection. METHODS: Thirty-seven patients (20 females and 17 males, age 36 +/- 2 years) with inactive Crohn disease (CDAI < 150) were studied: 15 patients after ileocecal resection and 22 non-operated patients; 12 had small bowel disease and 10 had large bowel disease. Nineteen healthy subjects (10 female; 9 male, age 30 +/- 2 years) served as controls. Gallbladder volumes were measured in the fasting state and at regular intervals for 2 h after ingestion of a solid meal (780 kcal). Blood samples were drawn at regular intervals for determination of cholecystokinin (CCK) and peptide YY (PYY). RESULTS: Fasting gallbladder volumes were significantly (P < 0.05) reduced in patients with large bowel disease (20.8 +/- 2.1 ml) or after ileocecal resection (18.3 +/- 2.4 ml) compared to patients with small bowel disease (28.0 +/- 2.1 ml) and controls (27.2 +/- 1.8 ml). Fasting plasma CCK levels were significantly (P < 0.05) higher in patients with large bowel disease or after ileocecal resection compared to patients with small bowel disease and controls. Postprandial gallbladder emptying and endogenous plasma CCK and PYY secretion in patients with Crohn disease were not different from controls. CONCLUSIONS: Fasting gallbladder volume is decreased and fasting plasma CCK levels are increased in patients with Crohn disease of the large bowel and patients after ileocecal resection. Postprandial gallbladder motility, CCK and PYY release were not affected in patients with Crohn disease.  相似文献   
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Dose-related effects of motilin on proximal gastrointestinal motility   总被引:5,自引:0,他引:5  
AIM: To assess non-invasively the dose-response relations for the effects of exogenous motilin on antrum contraction frequency, gall-bladder volume and gastric myoelectrical activity. METHODS: In a double-blind, randomized, placebo-controlled, five-way crossover study, 10 fasted healthy volunteers were infused intravenously with synthetic human motilin (0.5, 1, 2 and 4 pmol x min/kg) or placebo for 60 min. Gall-bladder volume and antrum contractions were assessed by ultrasonography and gastric myoelectrical activity by electrogastrography. Motilin concentrations were measured using a radioimmunoassay. RESULTS: Baseline plasma motilin levels (60 pmol/L) were similar for all treatments. Motilin levels increased upon the start of infusion and rapidly returned to baseline after cessation of the infusion. At motilin doses of 2 and 4 pmol.min/kg, the antrum contraction frequency was significantly augmented, with maximum differences of two contractions per 2-min interval compared to placebo, while no changes in gastric myoelectrical activity were observed. Changes in gall-bladder volume were not significantly different for any of the motilin doses compared to placebo. CONCLUSIONS: Motilin increased antrum contraction frequency, whereas no effect on gastric myoelectrical activity was observed. Antrum contraction frequency appears to be a useful biomarker for motilin efficacy, and motilin doses of 2 and 4 pmol x min/kg were equally effective.  相似文献   
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