Biomedical subjects

J B Jansen

Publications and source records attributed to J B Jansen.

At least 145 records · Page 8Linked to original sources

PubMed1993

Effects of indomethacin on intragastric pH and meal-stimulated serum gastrin secretion in rheumatoid arthritis patients.

The effects of oral indomethacin on intragastric pH and serum gastrin were investigated in rheumatoid arthritis patients. Nine patients (1 male, 8 female) without a history of peptic ulcer disease and 6 patients with a history of peptic ulcer disease (5 male, 1 female) were studied. To obviate Helicobacter pylori infection as a confounding factor, only patients with positive H. pylori serology were included. After a 5-day period of placebo treatment and after a 5-day period of indomethacin (50 mg t.d.s.; total dose 750 mg), 24-h intragastric pH and basal and meal-stimulated serum gastrin levels were measured in a double-blind placebo controlled cross-over study. There were no differences in the median 24-h pH values between placebo and indomethacin users irrespective of peptic ulcer disease history. Indomethacin resulted in a higher basal and stimulated gastrin response than placebo in patients with a history of peptic ulcer disease. The basal and incremental responses were lower in patients with a history of peptic ulcer disease than in patients without a history of peptic ulcer disease, both during indomethacin and placebo. The same basal and stimulated incremental serum gastrin responses were found during placebo and indomethacin treatment in patients without a history of peptic ulcer disease. No correlation was established between median 2-h post-prandial intragastric pH and post-prandial incremental serum gastrin concentration. We conclude that indomethacin does not influence the intragastric pH of rheumatoid arthritis patients irrespective of history of peptic ulcer disease.

Administration, Oral↗

PubMed1993

Short report: smoking habits and the acquisition of metronidazole resistance in patients with Helicobacter pylori-related gastritis.

Thirty-three dyspeptic patients with colonization of Helicobacter pylori in the gastric antrum were treated with tripotassium dicitrate bismuthate 120 mg q.d.s. for 28 days and metronidazole 250 mg q.d.s. for 10 days starting on day 19. Five weeks after cessation of this treatment regimen H. pylori was eradicated in 23 patients. In 8 of the remaining 10 patients, H. pylori had become resistant to metronidazole. In this study resistance was significantly associated with smoking habits, but not with age, bacterial load, gastritis score or alcohol consumption.

Adult↗

PubMed1993

Effect of ageing on postprandial conjugated and unconjugated serum bile acid levels in healthy subjects.

Colorectal cancer is a disease of elderly subjects. A decreased ileal absorption of bile acids in elderly subjects may lead to an increased exposure of the colonic mucosa to secondary bile acids. This may contribute to an enhanced risk of colorectal cancer. In this study fasting and postprandial conjugated and unconjugated serum levels of cholic, chenodeoxycholic, and deoxycholic acid in 12 elderly and 12 younger subjects were investigated. Intestinal transit time, gallbladder emptying and jejunal bacterial flora were also studied in both age groups. Fasting levels of conjugated and unconjugated serum bile acids were similar in both age groups. Postprandial levels of all individual conjugated bile acids increased to a significantly higher extent in the younger subjects. Postprandial unconjugated serum bile acid levels did not differ significantly between both age groups, although unconjugated deoxycholic levels tended to increase to higher levels in the elderly. Results of jejunal bacterial counts, gallbladder emptying and intestinal transit time were similar in both groups. These data suggest that conjugated bile acids are reabsorbed less effectively in elderly subjects.

Adult↗

PubMed1993

Effect of duodenal juice on bombesin-stimulated cholecystokinin release during loxiglumide administration in man.

Stimulation of cholecystokinin release by bombesin in augmented by cholecystokinin receptor blockade with loxiglumide. We hypothesize that this augmented cholecystokinin release results from inhibition of the pancreatico-biliary response to bombesin during cholecystokinin receptor blockade. To test this hypothesis, we infused bombesin for 180 min in six healthy subjects Three bombesin-infusion experiments were performed in each subject in random order on different days. In two of these experiments loxiglumide was co-infused with bombesin, while in the third experiment saline was co-infused with bombesin. In one of the loxiglumide experiments, duodenal juice, collected on the previous day during infusion of cholecystokinin-GIH, was reperfused intraduodenally during the second hour of bombesin infusion. In the saline experiment, the integrated cholecystokinin response during the first hour of bombesin-infusion (262 +/- 63 pmol 60 min-1) was significantly (P < 0.01) higher than during the second (88 +/- 26 pmol 60 min-1) and third (87 +/- 31 pmol 60 min-1) hour of bombesin-infusion. Loxiglumide augmented bombesin-stimulated cholecystokinin secretion from 262 +/- 63 pmol 60 min-1 to 453 +/- 63 pmol 60 min-1 in the first hour of bombesin infusion (P < 0.01). Integrated cholecystokinin values in the second (489 +/- 90 pmol 60 min-1) and third (450 +/- 74 pmol 60 min-1) hour of the loxiglumide experiment, were significantly (P < 0.01) higher than in the saline experiment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Diagnostic value of serum pepsinogen C in patients with raised serum concentrations of pepsinogen A.

Hypopepsinogenaemia A is often found in patients with gastric atrophy and gastric surgery. In these conditions serum pepsinogen C provides additional diagnostic information, especially when expressed as pepsinogen A:C ratio. Hyperpepsinogenaemia A has been shown in patients with duodenal ulcer disease, Zollinger-Ellison syndrome, hypertrophic gastropathy, chronic renal failure, and during omeprazole treatment. As patients with hyperpepsinogenaemia A often overlap in symptoms, endoscopical findings, and serum gastrin values, this study has evaluated whether measurement of serum pepsinogen C in subjects with hyperpepsinogenaemia A can help in differentiating clinical conditions. Serum concentrations of pepsinogen A and C were measured in serologically Helicobacter pylori negative blood transfusion donors (127) as reference population, and in patients with Zollinger-Ellison syndrome (24), duodenal ulcer (50), hypertrophic gastropathy (5), and chronic renal failure (50), and also in reflux oesophagitis patients on longterm omeprazole treatment (28). A low pepsinogen A:C ratio was found in all patients with hypertrophic gastropathy. A pepsinogen A:C ratio above the critical value of 4.7 was found in 14 (70.0%) of the Zollinger-Ellison patients, two (9.5%) of the duodenal ulcer patients, 11 (25.6%) of the patients with chronic renal failure, and in one (7.1%) of the patients receiving longterm omeprazole treatment. In fact, all but three hyperpepsinogenaemia A patients with a pepsinogen A:C ratio greater than 4.7 and normal renal function had the Zollinger-Ellison syndrome. In patients with hyperpepsinogenaemia A, a low pepsinogen A:C ratio may point to hypertrophic gastropathy, while a pepsinogen A:C ratio greater than 4.7 is suggestive for the Zollinger-Ellison syndrome.

Adult↗

PubMed1993

Postprandial gall bladder motility and hormone release during intermittent and continuous subcutaneous octreotide treatment in acromegaly.

Repeated daily injections of the somatostatin analogue, octreotide (SMS201-995, Sandostatin) are an effective treatment for acromegaly, but lead to gall stone formation in about 50% of cases during longterm treatment. This is probably because of impaired gall bladder contraction. This study examined whether the timing of intermittent injections in relation to meals, or alternatively, continuous 24 hour subcutaneous octreotide infusion (CSOI) might avert adverse effects on gall bladder contraction. In six patients with active acromegaly, gall bladder volume, plasma cholecystokinin (CCK), and pancreatic polypeptide (PP) were measured in the fasting state and after consumption of a fatty meal. Measurements were made on five separate days: (a) without treatment, (b) 45 minutes after 100 micrograms octreotide given subcutaneously, (c) four hours after 100 micrograms octreotide given subcutaneously, (d) eight hours after 100 micrograms octreotide given subcutaneously, and (e) during CSOI of 300 micrograms/24 h for two weeks. Without treatment, postprandial gall bladder contraction was 86.2 (2.1%). Fasting gall bladder volume increased after octreotide injection and was almost doubled during CSOI. Octreotide injections impaired postprandial gall bladder contraction as well as CCK and PP release for at least four hours. Eight hours after injection and during CSOI, postprandial gall bladder contraction was partly restored (43.4% and 50.8% respectively). Postprandial CCK release was normal at eight hours after injection but very low during CSOI. PP release was suppressed by each mode of octreotide treatment. This study indicates that octreotide injections impair postprandial gall bladder contraction for at least four hours. Eight hours after injection and during CSOI, gall bladder contraction is partly restored.

Acromegaly↗

PubMed1993

Effect of acute hyperglycaemia on gall bladder contraction induced by cholecystokinin in humans.

This study examined the effect of acute hyperglycaemia, induced by intravenous glucose, on gall bladder motility. Six healthy volunteers were studied in random order on three occasions during normoglycaemia and hyperglycaemia with blood glucose concentrations stabilised at 8 and 15 mmol/l. Gall bladder volumes, measured with ultrasonography, were studied before and during infusion of stepwise increasing doses of cholecystokinin (CCK-33; 0.25, 0.5, and 1.0 IDU.kg-1.h-1). Each dose was given for 30 minutes. Pancreatic polypeptide (PP) secretion was determined as an indirect measure of cholinergic tone. Infusion of CCK-33 resulted in significant dose dependent reductions in gall bladder volume in all three experiments. Compared with normoglycaemia the gall bladder contraction was significantly (p < 0.05) reduced during infusion of 0.25 and 0.5 IDU kg-1.h-1 CCK-33 in the 8 mmol/l hyperglycaemic experiment, and during infusion of 0.25, 0.5, and 1.0 IDU kg-1.h-1 CCK-33 in the 15 mmol hyperglycaemic experiment. During hyperglycaemia basal plasma PP concentrations and PP secretion in response to CCK-33 were significantly (p < 0.05) reduced. It is concluded that blood glucose concentrations affect gall bladder motility, that an acute hyperglycaemia at 8 and 15 mmol/l reduces the gall bladder responsiveness to CCK-33 in a dose dependent manner, and that hyperglycaemia reduces basal and CCK-33 stimulated plasma PP concentrations, suggesting impaired cholinergic activity during hyperglycaemia.

Adult↗

PubMed1993

Inhibition of omeprazole induced hypergastrinaemia by SMS 201-995, a long acting somatostatin analogue in man.

Whether the long acting somatostatin analogue SMS 201-995 (octreotide, Sandostatin) could inhibit the basal and meal stimulated hypergastrinaemia and hyperpepsinogenaemia induced by omeprazole was investigated. Eight healthy subjects were randomised to receive five day courses of SMS 201-995 (25 micrograms subcutaneously three times daily), omeprazole (40 mg once a day), a combination of both drugs, or placebo. Basal and meal stimulated serum gastrin and basal serum pepsinogen A and C values were measured the day before treatment, on day five of treatment, and the day after each course of treatment. Omeprazole caused significant increases in basal and meal stimulated peak and integrated serum gastrin values and pepsinogen A and C levels, which were still significantly raised the day after stopping omeprazole treatment. Giving SMS 201-995 with omeprazole significantly reduced any omeprazole induced increases in basal and meal stimulated peak and integrated serum gastrin levels; serum pepsinogen A and C values were significantly inhibited too. Serum gastrin values during combined therapy were not significantly different from those during placebo treatment, whereas pepsinogen A and C levels were still significantly raised. On the day after stopping combined therapy, basal and meal stimulated peak and integrated serum gastrin and serum pepsinogen C (but not pepsinogen A) levels were not significantly different from values obtained on the day after stopping omeprazole alone. SMS 201-995 without omeprazole significantly inhibited basal and meal stimulated peak and integrated serum gastrin levels. Pepsinogen A was also significantly inhibited by SMS 210-995, but the reduction in pepsinogen C failed to reach statistical significance. In conclusion, SMS 201-995 prevents basal and meal stimulated increases in serum gastrin during omeprazole therapy. This finding may have clinical importance in the few patients who have pronounced hypergastrinaemia because of profound long acting acid inhibition.

Adult↗

PubMed1993

Motor cycles with phase III in antrum are associated with high motilin levels and prolonged gallbladder emptying.

We examined the relationship of interdigestive gallbladder emptying with the different phases of the migrating motor complex (MMC) and with plasma levels of cholecystokinin (CCK) and motilin. In 10 volunteers 20 cycles of the MMC were recorded. In 11 cycles phase III occurred in antrum and duodenum (group 1). In nine cycles phase III was observed only in duodenum (group 2). In group 1 gallbladder emptying started at 30% of total cycle length and continued until the end of the cycle. Maximal gallbladder emptying was 33.3 +/- 3.3% (SE). In group 2 gallbladder emptying also started at 30% of total cycle length but ended at 60%. Maximal gallbladder emptying in this group was 24.3 +/- 3.1% (P < 0.05). Motilin levels were higher in group 1 than in group 2 during phase IIB (240.1 +/- 28.5 and 142.1 +/- 30.9 pg/ml, respectively, P < 0.05) and during phase III (210.8 +/- 24.3 and 93.5 +/- 12.5 pg/ml, respectively, P < 0.05). We conclude that: 1) phase III activities starting in the antrum are preceded by greater and prolonged gallbladder emptying, higher motilin levels, and higher intraduodenal bile acid concentrations than phase III activities starting in the duodenum and 2) no relationship between interdigestive gallbladder motility and CCK levels could be demonstrated.

Adult↗

PubMed1993

Effect of short-term administration of omeprazole on serum gastrin and pepsinogens in antrectomized patients.

Omeprazole, a potent and long-acting inhibitor of gastric acid secretion, is known to increase both serum gastrin and pepsinogen A and C levels in unoperated subjects. It has been suggested that the rise in serum pepsinogens is mediated by the omeprazole-induced increase in serum gastrin. This study was undertaken to determine the role of gastrin in hyper-pepsinogenemia induced by antisecretory therapy. We have studied the effect of a 5-day course of 40 mg of omeprazole daily on fasting serum gastrin and pepsinogen A and C levels in 14 patients with an antrectomy and a Billroth I anastomosis (n = 8) or a Billroth II anastomosis (n = 6). In antrectomized patients omeprazole failed to induce any increase in basal serum gastrin. On the other hand, omeprazole increased significantly serum pepsinogen A levels in both Billroth I and II patients, while the rise in serum pepsinogen C level was significant in Billroth I, but just failed to reach statistical significance in Billroth II patients. We conclude that the stimulation of serum pepsinogens A and C by a short-term treatment with omeprazole is not mediated by increases in serum gastrin. This study further shows that omeprazole stimulates gastrin release only from the antrum and not from extra-antral sources.

Adult↗

PubMed1993

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

This double blind study was undertaken to determine whether infusion of bombesin (BBS) inhibits the intake of a carbohydrate-rich meal in nine lean healthy subjects and whether inhibition of food intake by BBS is mediated by cholecystokinin (CCK). During infusion of BBS, the amount of food eaten was decreased compared to that after saline infusion (482 +/- 74 vs. 602 +/- 68 g; P < 0.01). Subjective criteria of satiation were also significantly affected by BBS infusion (P < 0.05). Administration of the CCK receptor antagonist loxiglumide (CR1505) to six of the subjects did not prevent the decrease in food intake due to BBS (365 +/- 69 g) or the subjective criteria for satiety. Furthermore, the amount of food eaten during loxiglumide treatment alone (537 +/- 109 g) was not different from that during control saline infusion. In conclusion, infusion of BBS inhibits the intake of a carbohydrate-rich meal by a CCK-independent mechanism.

Adult↗

PubMed1993

Long-term omeprazole therapy does not affect Helicobacter pylori status in most patients.

Fifty-one patients were treated with 20-60 mg omeprazole for reflux oesophagitis resistant to H2-blocker therapy during a mean of 49 months of follow-up. With use of a standardized enzyme-linked immunosorbent assay technique specific IgG and IgG Helicobacter pylori antibodies were determined in serum obtained at the start of therapy and at the most recent visit. At the start of therapy 26 patients (51%) had evidence of H. pylori infection, as demonstrated by increased IgG and IgA antibody levels. During follow-up, 4 of these 26 patients (15%) became H. pylori seronegative. It is concluded that long-term treatment with omeprazole has no effect on H. pylori status in most patients.

Aged↗

PubMed1993

Gastrointestinal disturbances with obesity.

Steatosis and steatohepatitis are associated with obesity. Despite florid histological changes, patients with non-alcoholic steatohepatitis generally remain asymptomatic, and it usually runs a relatively benign course. An elevated insulin level may be important in the pathogenesis. There is a marked regression of fatty changes after weight reduction. In obese subjects the risk of developing gallstones is increased due to an increased saturation of gallbladder bile with cholesterol and possible gallbladder stasis. During weight reduction with very low calorie diets the incidence in gallstones increases probably because of an increased saturation of bile during the loss of weight. Ursodeoxycholic acid appears to be a promising prophylactic agent. Chenodeoxycholic acid is not useful for these subjects. There is controversy over whether obesity contributes to gastroesophageal reflux and gastric emptying disturbances. There are changes in gastrointestinal peptide plasma levels in obesity but it is not clear if this contributes to its development. The risk for high-risk colorectal adenomas and carcinomas is reported to be increased in obese males. Vertical banded gastroplasty and gastric bypass procedures are nowadays the surgical options for the treatment of obesity. Nutritional deficiencies, particularly of vitamin B12, folate and iron are common after gastric bypass and must be sought and treated. Dumping is another potential complication of this operation. If stenosis and gastric outlet obstruction develop endoscopic dilatation is a good therapeutic option.

Animals↗

PubMed1993

Postprandial conjugated and unconjugated serum bile acid levels after proctocolectomy with ileal pouch-anal anastomosis.

In patients with ileal pouch-anal anastomosis (IPAA) bile acid reabsorption may be impaired, and stasis may lead to deconjugation and dehydroxylation of bile acids as a result of bacterial overgrowth. We therefore studied fasting and postprandial conjugated and unconjugated serum levels of cholic (CA), chenodeoxycholic (CDCA), and deoxycholic acid (DCA) in 11 patients who underwent proctocolectomy with IPAA and in 11 healthy controls. Fasting levels of conjugated DCA but not CA and CDCA were significantly lower in IPAA patients. Postprandially, conjugated bile acid levels were significantly lower in IPAA patients. Postprandial unconjugated CA levels were significantly higher and CDCA levels tended to be higher in IPAA patients, whereas unconjugated DCA levels were lower in IPAA patients. These data suggest that reabsorption of conjugated bile acids is impaired after IPAA; deconjugation of bile acids may result from bacterial overgrowth secondary to stasis in the pouch; and dehydroxylation of bile acids is decreased after proctocolectomy with IPAA.

Adult↗

PubMed1993

Reproducibility of ambulatory intragastric pH monitoring.

Ambulatory 24-hour intragastric pH monitoring is nowadays the standard technique for assessing intragastric acidity. For (patho)physiological and pharmacological studies the method has to be sensitive and reproducible. Intragastric acidity was measured continuously by means of intragastric electrodes in the gastric corpus. In order to assess the reproducibility of the test, we repeated it test twice on separate days under standardized conditions in 8 healthy subjects. Subjects were fully ambulatory and no medication was administered. We found no significant difference between 24-hour median pH values during both study days [1.45 (range 1.20-1.90) and 1.40 (1.20-2.00), day 1 and 2, respectively]. There was a significant overall correlation between consecutive 30-min median pH values during 24 hours (r = 0.97, p < 0.0001). Over 24 hours and during the day the technique was able to detect consistent pH changes of > 0.1 pH units, but during the night only changes of > 0.3 pH units could be detected, due to nocturnal pH fluctuations in two subjects. This study shows that ambulatory 24-hour intragastric pH monitoring is reproducible and is able to detect small changes in gastric acidity.

Adult↗

PubMed1993

Cholecystokinin and satiation.

Peripheral signals from stomach and small intestine are believed to induce satiation. In experimental animals, satiation factors can be transfused pointing to the humoral nature of the signal. Cholecystokinin (CCK) may be an important mediator, since infusion of exogenous CCK has been demonstrated to induce satiation and to inhibit gastric emptying. However, whether this effect of CCK is a physiological or pharmacological event is a matter of controversy. The significance of exogenous CCK or stimulation of endogenous CCK in the possible treatment of obesity requires further study.

Animals↗

PubMed1993

[Rectal endosonography for perirectal and non-tumor rectal changes].

The value of rectal endosonography was retrospectively evaluated in 39 patients with various rectal and perirectal diseases. Endosonography proved to be very helpful in demonstrating or excluding abscesses. In patients with aspecific minor inflammatory rectal diseases, endosonography was not very helpful. Endosonography is complementary to other imaging techniques like CT and MRI in establishing perirectal tumors. Endosonography shows the relationship of the rectal wall with an extrarectal tumor and is capable of demonstrating the extent of smaller tumors. It may contribute to the diagnosis of endometriosis in the rectovaginal space. In patients with anal pain endosonography can play an important role in demonstrating or excluding fistulas, abscesses and other diseases.

Abscess↗

PubMed1993

Relationship between hunger and plasma cholecystokinin during weight reduction with a very low calorie diet.

Based on a large number of studies in various species, cholecystokinin (CCK) is considered to function as an important regulator of satiety. The present study was undertaken to determine the relationship between hunger score and basal and postprandial plasma CCK secretion, in six obese subjects before and after weight loss with modified fasting. Modified fasting (modifast, 240 kcal/day) for ten weeks induced a mean weight loss of 23 kg. The hunger score was reduced by about 75%. However, basal and plasma CCK release induced by 80 kcal of modifast were not different before and after ten weeks of modifast treatment. Thus, the reduction of hunger during modified fasting is not mediated by circulating CCK.

Adult↗