Biomedical subjects

J B Jansen

Publications and source records attributed to J B Jansen.

At least 127 records · Page 7Linked to original sources

PubMed1994

Serum pepsinogens in patients with gastric diseases or after gastric surgery.

As no comparative study is available on the categorized serum pepsinogen A and C concentrations, we have measured serum pepsinogens in patients with gastric diseases and after gastric surgery. Hyperpepsinogenemia A (> 120 micrograms/l) occurred frequently in patients with the Zollinger-Ellison syndrome (71%) and hypertrophic gastropathy (100%), whereas hypopepsinogenemia A (< 17 micrograms/l) was found mostly in patients with achlorhydria (87%) and after total gastrectomy (100%). Patients with the Zollinger-Ellison syndrome frequently (58%) had hyperpepsinogenemia C (> 40 micrograms/l), which was also the case in all patients with hypertrophic gastropathy who had in addition a low pepsinogen A:C ratio (< 1.6). Patients with achlorhydria, hypertrophic gastropathy, or after total gastrectomy fell into an aberrant category. From this study we conclude that measurement of serum pepsinogen A and C and calculation of their ratio yield information useful for differentiation of gastric abnormalities.

Aged↗

PubMed1994

Gallbladder motility and cholecystokinin release during long-term enteral nutrition in patients with Crohn's disease.

BACKGROUND: Gallbladder bile stasis during long-term continuous enteral feeding may contribute to the high prevalence of gallstones in patients with Crohn's disease. We therefore examined the effects of continuous enteral nutrition on gallbladder motility and cholecystokinin (CCK) release in six patients. METHODS: Gallbladder volume was measured ultrasonographically for 12 h on days 1 (start), 8, 22 (6-h interruption of enteral feeding), 36, and 43 (end) of enteral feeding. Plasma CCK was assessed at several time points. RESULTS: Initial fasting gallbladder volume was 19.3 +/- 4.5 (mean +/- SEM) ml, which decreased to 4.9 +/- 3.6 ml after start of feeding. CCK increased from 1.5 +/- 0.3 to 3.9 +/- 1.1 pmol/l. On days 8 and 36 the gallbladder was almost completely contracted, and CCK increased to 7.5 +/- 2.7 and 8.3 +/- 2.6 pmol/l, respectively. On days 22 and 43 gallbladder volume increased, and CCK decreased rapidly to fasting concentrations after interruption of feeding. CONCLUSIONS: During continuous enteral nutrition the gallbladder is completely contracted, and CCK concentrations remain elevated. It is therefore unlikely that long-term enteral nutrition contributes to the increased prevalence of gallstones in patients with Crohn's disease.

Adolescent↗

PubMed1994

Significant satiety effect of bombesin in lean but not in obese subjects.

The aim of this work was to determine whether infusion of bombesin inhibits intake of a carbohydrate-rich meal in lean and obese women. A double blind study was carried out using bombesin or saline infusion. The subjects were nine lean and nine obese women of the same age. Food intake and hunger feelings were measured. During infusion of bombesin, the amount of food eaten by the lean individuals (294 +/- 55 g) was significantly less than during infusion of saline (467 +/- 69 g, P < 0.01). However, bombesin induced no significant feeding suppression in the obese women when compared to saline (431 +/- 60 vs 499 +/- 99 g). Subjective hunger feelings were significantly affected by bombesin infusion in the lean subjects only. It was concluded that bombesin infusion inhibits food intake and increases satiety in lean women, whereas obese women are less sensitive to these bombesin-induced satiety effects.

Adult↗

PubMed1994

Nutrient-specific effects of modified sham feeding on pancreatic polypeptide release.

OBJECTIVE: To study the effect of meal composition on pancreatic polypeptide release during modified sham feeding. DESIGN: In random order and on separate occasions, isocaloric, isothermic, isoosmotic, homogenized meals (1050 kJ; 250 kcal) either rich in fat (walnuts; 64 g fat, 7 g protein, 15 g starch per 100 g), protein (codfish, 1 g fat, 23 g protein per 100 g) or carbohydrates (bananas; 22 g starch, 1 g protein per 100 g) were sham-fed for 30 min by tasting and spitting out the meal. The plasma pancreatic polypeptide response was monitored by radioimmunoassay at 10 min intervals from 20 min before to 120 min after modified sham feeding. SETTING: Department of Gastroenterology and Hepatology of a University Hospital. SUBJECTS: Seven healthy volunteers: 3 male, 4 female; age 45 (range 30-77) years. RESULTS: Integrated plasma pancreatic polypeptide responses to modified sham feeding of codfish (1088 +/- 395 pM*120 min; P < 0.05) and walnuts (1200 +/- 542 pM*120 min) were distinctly higher (P < 0.05) than to modified sham feeding of bananas (-390 +/- 291 pM*120 min). CONCLUSIONS: These results demonstrate that the pancreatic polypeptide response to modified sham feeding is dependent on the composition of the meal.

Adult↗

PubMed1994

A comparative study of gastrectomy without vagotomy with either Roux-en-Y or Billroth II anastomosis in peptic ulcer.

Since recent small uncontrolled studies have suggested that surgery for peptic ulcer comprising partial gastrectomy with Roux-en-Y anastomosis without vagotomy effectively prevents postoperative enterogastric reflux without increasing ulcer recurrence rate, we have compared mortality, ulcer recurrence rate, and complaints in ulcer patients who had undergone partial gastrectomy with either Roux-en-Y (n = 47) or Billroth II anastomosis (n = 47). The groups were comparable with regard to age, sex, ulcer localisation, indication for surgery and number of emergency procedures. During postoperative follow-up, seven patients with Roux-en-Y have died, compared with nine patients with Billroth II gastrectomy. In two of the seven patients who died after Roux-en-Y gastrectomy, but in none of the nine who died after Billroth II resection, death was unequivocally related to postoperative ulcer recurrences. At 1, 2, 3 and 4 years postoperatively, 90 vs. 100% (not significant), 78 vs. 98% (p < 0.01), 72 vs. 95% (p < 0.01) and 72 vs. 95% (p < 0.01) of the patients were in remission after Roux-en-Y and Billroth II gastrectomy, respectively. All ulcers were localized at or just distal to the anastomosis, and were diagnosed within the first 3 postoperative years. We conclude that in peptic ulcer patients the ulcer recurrence rate after Roux-en-Y gastrectomy without vagotomy is considerably higher than after Billroth II resection. Thus, gastrectomy with Roux-en-Y anastomosis without vagotomy cannot be recommended as the primary procedure in patients undergoing partial gastrectomy for peptic ulcer disease.

Adolescent↗

PubMed1994

Plasma cholecystokinin and pancreatic polypeptide secretion in response to bombesin, meal ingestion and modified sham feeding in lean and obese persons.

Disturbed satiety mechanisms may contribute to obesity. There has been speculation that cholecystokinin (CCK) and pancreatic polypeptide (PP) are involved in the regulation of satiety. We have therefore investigated whether there are differences between healthy lean and healthy non-diabetic obese volunteers in plasma CCK or PP release after a neuropeptidergic stimulation with bombesin and after infusion of a mixed meal. There were no differences in plasma CCK between groups either basally or in response to either form of stimulation. However, the plasma PP concentrations after the meal were significantly less in obese (2845 +/- 404 pM.min) than in lean subjects (5569 +/- 997 pM.min), whereas the plasma PP concentrations during bombesin were similar in both groups. We tested two other groups of nine obese and lean subjects to determine whether a disturbed vagal function could be the cause of the diminished plasma PP in obese persons, by studying the effect of modified sham feeding (MSF) on plasma PP. However, there were no significant differences in the plasma PP response to MSF between lean and obese subjects. We conclude that there are no differences between lean and obese persons in plasma CCK secretion in response to infusion of the neuropeptide bombesin or to ingestion of a mixed meal. However, the plasma PP after a mixed meal, is markedly diminished in obese subjects. This could not be attributed to a disturbed vagal cephalic stimulation.

Adult↗

PubMed1994

[The value of CT for the diagnosis of rectal cancer recurrence. A ROC study and a retrospective analysis].

To assess the ability of CT to detect recurrent tumor growth after colorectal surgery for rectal carcinoma independently of clinical bias and patient selection, a receiver operator characteristic (ROC) analysis was performed. A set of 100 CT scans, 50 scans of 35 patients with proven recurrent disease, and 50 normal postoperatives of 37 patients were read by four observers without knowledge of the present clinical status. The four ROC curves had an area under the curve (AUC) ranging from 0.69 to 0.78 (SD from 0.046 to 0.053). The slightly raised AUC indicates the poor diagnostic power of CT in discriminating between postoperative changes and recurrence. In a retrospective analysis of the CT scans of the 72 patients CT had an overall accuracy of 83%. CT was unable to detect small anastomotic recurrence. The morphological characteristics of recurrence were not specific, but an irregular globular mass with or without inhomogeneity or asymmetry strongly suggests recurrent tumor and stresses the need for further evaluation, e.g., CT-guided biopsy.

Female↗

PubMed1993

Effects of a physiological dose of cholecystokinin on food intake and postprandial satiation in man.

CCK-33 was infused intravenously to groups of 9 lean and 9 obese volunteers in doses that elicited plasma CCK concentrations in the physiological range. The effect of these infusions on food intake and satiety signals was compared with the effect of saline infusions in the same subjects. Food intake (486 +/- 52 g; mean +/- S.E.M.) was slightly, but not significantly decreased (553 +/- 55 g after saline), and hunger and fullness feelings after eating were unaffected, in both of the two groups. We conclude that the infusion of CCK-33 to plasma levels comparable to those observed after a fatty meal does not have a major effect on food intake and postprandial hunger feelings.

Adult↗

PubMed1993

Effect of cholestyramine and cholecystokinin receptor antagonist CR1505 (loxiglumide) on lower esophageal sphincter pressure in man.

Cholecystokinin (CCK) decreases lower esophageal sphincter pressure (LESP) in man. Cholestyramine, a nonabsorbable bile salt binding resin, stimulates endogenous CCK secretion. We have investigated the effect of oral ingestion of 16 g cholestyramine without and with infusion of the CCK receptor antagonist CR1505 (loxiglumide, 15 mg/kg/90 min) on LESP in seven healthy subjects. LESP was recorded for 90 min, in 10-min intervals, with the pull-through technique using a four-lumen water-perfused catheter. Oral ingestion of cholestyramine resulted in a significant (P < 0.05) decrease in LESP, starting from 10 min and continuing during the entire experiment (basal LESP: 11.8 +/- 2 mm Hg, minimal value reached during cholestyramine: 7.3 +/- 1 mm Hg; P < 0.05). Pretreatment with loxiglumide completely antagonized the effect of cholestyramine on LESP. Infusion of loxiglumide without cholestyramine did not affect basal LESP. It is concluded that: (1) cholestyramine significantly reduces LESP; (2) this reduction in LESP does not occur after pretreatment with loxiglumide, indicating that cholestyramine influences LESP through CCK release; and (3) basal LESP is not regulated by CCK.

Adult↗

PubMed1993

Hyperglycemia modulates gallbladder motility and small intestinal transit time in man.

The aim of the present study was to investigate the effect of acute hyperglycemia on (1) the intestinal phase of gallbladder contraction induced by the intraduodenal administration of emulsified fat, and (2) the small intestinal transit time measured by the lactulose breath hydrogen test. Six healthy volunteers were studied in random order during normoglycemia and hyperglycemia (blood glucose levels 15 mmol/liter). Gallbladder volumes were measured with ultrasonography. Administration of 1 and 2 g/hr of fat resulted in significant reductions in gallbladder volumes from 24 +/- 2 cm3 to 11 +/- 1 cm3 (P < 0.05) and 8 +/- 1 cm3 (P < 0.05), respectively during normoglycemia, and from 24 +/- 2 cm3 to 21 +/- 2 cm3 (P < 0.05) and 16 +/- 2 cm3, respectively (P < 0.05) during hyperglycemia. Compared to normoglycemia, the gallbladder contraction was significantly (P < 0.05) reduced during hyperglycemia. No significant differences in CCK secretion were observed between experiments. Small intestinal transit time during hyperglycemia (101 +/- 12 min) was significantly (P < 0.05) prolonged compared to normoglycemia (57 +/- 12 min). During hyperglycemia, basal PP levels and PP secretion in response to intraduodenal fat were significantly (P < 0.05) reduced compared to normoglycemia. It is concluded that (1) low doses of intraduodenal emulsified fat result in significant gallbladder contraction and CCK secretion, (2) acute hyperglycemia inhibits intraduodenal fat induced gallbladder contraction, (3) acute hyperglycemia does not affect the intraduodenal fat induced CCK secretion, (4) small intestinal transit is significantly prolonged during acute hyperglycemia, and (5) acute hyperglycemia inhibits basal and stimulated plasma PP secretion, suggesting impaired vagal-cholinergic tone during hyperglycemia.

Acute Disease↗

PubMed1993

Contribution of gastrin to cysteamine-induced gastric acid secretion in rats.

The role of circulating gastrin in cysteamine induced gastric acid secretion was examined in conscious male Wistar rats, provided with a portal vein catheter, a jugular vein catheter and a pyloric drainage tube. Intravenous infusion of 0.3 nmol/kg.30 min of gastrin 17-l resulted in serum gastrin concentrations of 1138 +/- 151 pg/ml and gastric acid secretion of 104 +/- 36 mumol H+/kg.30 min. This acid response was abolished by intravenous injection of 60 microliters of a gastrin-antiserum, indicating the efficacy of immunoneutralization with this antiserum in vivo. Intravenous bolus administration of 125 mg/kg of cysteamine induced increases in serum gastrin concentration (864 +/- 96 pg/ml) and gastric acid outputs (107 +/- 27 mumol H+/kg.30 min) not significantly different from the gastrin 17-l infusion experiments. Gastrin antiserum abolished cysteamine-induced gastric acid secretion, indicating that gastric acid secretion induced by 125 mg/kg of cysteamine is largely mediated by circulating gastrin in rats.

Animals↗

PubMed1993

Hyperglycemia reduces gallbladder emptying and plasma hormone secretion to modified sham feeding and regular feeding.

The purpose of this study was to investigate the effect of acute stable hyperglycemia on gallbladder motility, plasma cholecystokinin level and pancreatic polypeptide secretion. Gallbladder emptying in response to modified sham feeding and regular feeding was determined in six healthy subjects on two separate occasions during normoglycemia (serum glucose = 5 mmol/L) and during hyperglycemia (serum glucose = 15 mmol/L). Pancreatic polypeptide secretion was determined as an indirect measure of cholinergic tone. Gallbladder contraction in response to sham feeding during hyperglycemia (9% +/- 2%) was significantly (p < 0.05) reduced compared with that in normoglycemia (22% +/- 1%). During hyperglycemia, gallbladder emptying after meal ingestion (29% +/- 9%) was significantly (p < 0.05) less than that in normoglycemia (60% +/- 10%). Sham feeding did not affect plasma cholecystokinin levels. Regular feeding induced significant (p < 0.05) increases in plasma cholecystokinin levels in both experiments. However, integrated postprandial plasma cholecystokinin secretion was significantly (p < 0.05) reduced during hyperglycemia compared with that in normoglycemia (29 +/- 5 pmol.60 min vs. 58 +/- 10 pmol.60 min). Modified sham feeding-and feeding-stimulated pancreatic polypeptide secretion during hyperglycemia (235 +/- 95 pmol.90 min and 1,035 +/- 267 pmol.60 min, respectively) were significantly (p < 0.05) less than levels seen in normoglycemia (434 +/- 71 pmol.90 min and 1,961 +/- 219 pmol.60 min, respectively). This study indicates that gallbladder emptying and plasma hormone secretion in response to sham feeding and regular feeding are affected by blood glucose levels.

Adult↗

PubMed1993

Gallbladder responses to modified sham feeding: effects of the composition of a meal.

Changes in gallbladder contraction and plasma cholecystokinin release were studied following modified sham feeding of 3 different isocaloric meals rich in either fat, protein or carbohydrates in healthy volunteers, and results were compared with those following real feeding of comparable meals. In contrast to carbohydrate-rich meals (8 +/- 19 ml/120 min), fat- (-412 +/- 46 ml/120 min) and protein-rich meals (-352 +/- 42 ml/120 min) reduced integrated gallbladder volume (P < 0.05) in response to modified sham feeding. Plasma cholecystokinin levels were not significantly influenced by modified sham feeding of fat, protein or carbohydrates. Real feeding of a carbohydrate-rich meal also failed to significantly reduce gallbladder volume and to stimulate cholecystokinin release (-45 +/- 40 ml/120 min and 51 +/- 11 pmol/120 min, respectively), while real feeding of both fat- and protein-rich meals distinctly reduced gallbladder volume (-679 +/- 76 and -564 +/- 53 ml/120 min, respectively; P < 0.05) and increased cholecystokinin release (651 +/- 72 and 504 +/- 43 pmol/120 min, respectively; P < 0.05). This study demonstrates that gallbladder contraction during the cephalic phase of meal stimulation is dependent on the fat, protein and carbohydrate percentages of a meal, and is activated by different mechanisms than the intestinal phase of a meal.

Acetylcholine↗

PubMed1993

Glutathione and glutathione S-transferases in Barrett's epithelium.

Glutathione content, enzyme activity and isoenzyme composition of glutathione S-transferases were assayed in normal and Barrett's esophageal epithelium of ten patients with Barrett's esophagus. In addition, gastric and duodenal specimens from the same patients were also investigated. Glutathione content, glutathione S-transferase enzyme activity as well as glutathione S-transferase pi content were all significantly lower in Barrett's epithelium as compared to normal esophageal mucosa. In contrast, glutathione S-transferase class alpha enzymes are markedly expressed in Barrett's epithelium, whereas only low amounts are present in normal esophageal epithelium. Glutathione and glutathione S-transferase composition in Barrett's epithelium show striking similarities with gastric epithelium, whereas duodenal epithelium is provided with considerable higher amounts of glutathione and glutathione S-transferases, except for levels of glutathione S-transferase class pi, which are lower. A significant negative correlation exists between glutathione S-transferase enzyme activity in the mucosa along the gastrointestinal tract, and the tumour incidence. Since glutathione and glutathione S-transferase are correlated with protection against cellular or cytogenetic damage, the low content of glutathione and glutathione S-transferases in the Barrett's esophagus may be a factor of relevance for the increased tumour risk in this tissue.

Adult↗

PubMed1993

Response to adjuvant chemotherapy in primary breast cancer: no correlation with expression of glutathione S-transferases.

Of 139 node-positive breast cancer patients treated with adjuvant chemotherapy, the pre-treatment levels of glutathione S-transferase (GST) classes alpha, mu and pi, were determined by immuno-quantification on Western blots in cytosols of the primary tumours. Their expression was studied with respect to cytosolic oestrogen-receptor, progesterone-receptor and cathepsin D levels, and to the length of disease-free survival. GST class pi was negatively correlated with oestrogen receptor and progesterone receptor, and positively correlated with cathepsin D. There was no correlation between GST isoenzymes and the length of disease-free survival. These data suggest that glutathione S-transferases are not useful as markers to predict the response to adjuvant chemotherapy in human breast cancer.

Adult↗

PubMed1993

Attenuation of the gastric acid and serum gastrin-lowering effects of the prostaglandin E2 analog enprostil.

Enprostil, a synthetic prostaglandin E2 analog, has been shown to decrease gastric acid secretion and plasma gastrin levels during short-term treatment. However, effects of prolonged treatment with enprostil on these parameters in humans are unknown. We have studied the effects of 35 micrograms enprostil twice daily on 24-hour intragastric pH, basal gastrin, and meal-stimulated gastrin release in 10 healthy volunteers. Enprostil, 35 micrograms, was ingested twice daily for 4 weeks. Subjects were studied on day 0 (preentry) and days 1 and 29, when enprostil was taken 30 minutes before the first and third standard test meals at 9 AM and 5 PM. Enprostil significantly increased 24-hour median pH (p < 0.02) on day 1 but not on day 29. Enprostil had no significant effect on basal gastrin levels compared with placebo. However, on day 1, but not on day 29, postprandial gastrin levels were significantly lower compared with preentry (p < 0.05). On day 29 post-prandial gastrin levels after the second standard test meal were significantly higher compared with preentry data (p < 0.05). In conclusion, 35 micrograms enprostil twice daily reduced gastric acidity and serum gastrin levels on the first day of treatment, but this effect attenuated and even transiently reversed during a 4-week treatment period.

Adult↗

PubMed1993

Bombesin reduces food intake after a preload in man by a cholecystokinin-independent mechanism.

1. A double-blind study was undertaken to determine whether the infusion of bombesin inhibits the intake of a carbohydrate-rich meal, consumed 15 min after a 300 ml banana shake, in nine lean healthy subjects and whether the possible inhibition of food intake by bombesin is mediated by cholecystokinin. 2. The amount of food eaten during infusion of bombesin (267 +/- 60 g) and bombesin combined with the cholecystokinin-receptor antagonist loxiglumide (269 +/- 39 g) was slightly (P = 0.09) less than during saline infusion (384 +/- 40 g). In addition, preprandial feelings of hunger were significantly less during infusion of both bombesin and bombesin combined with loxiglumide. 3. In conclusion, infusion of bombesin tends to inhibit the intake of a carbohydrate-rich meal after a preload by a cholecystokinin-independent mechanism.

Adult↗

PubMed1993

Glutathione S-transferases in esophageal cancer.

Glutathione content and glutathione S-transferase enzyme activity as well as isoenzyme composition were studied in normal gastric cardia, normal squamous esophageal epithelium and corresponding malignant tumor of 10 patients with esophageal cancer. Mean values of glutathione (38 +/- 6 versus 36 +/- 12 nmol/mg protein) and glutathione S-transferase activity (532 +/- 44 versus 532 +/- 108 nmol/min mg protein) did not differ significantly between normal esophageal and tumor tissue. However, great individual differences exist. In two patients, glutathione S-transferase activity was much higher in the tumor (1081 and 1381 nmol/min mg protein) due to overexpression of class alpha, mu and pig glutathione S-transferases in one case, and of class mu and pi in the other case. In the other patients, glutathione S-transferase activity was equal (one case) or lower (seven cases) in the tumor. In normal gastric cardia glutathione content as well as glutathione S-transferase activity was significantly lower as compared to normal esophageal epithelium. In conclusion, in contrast to other gastrointestinal tumors, glutathione S-transferases are overexpressed in esophageal tumors in only a limited number of patients.

Adult↗