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Featured researches published by Jozef Janssens.


Gastroenterology | 1998

Role of impaired gastric accommodation to a meal in functional dyspepsia

Jan Tack; H. Piessevaux; B Coulie; Philip Caenepeel; Jozef Janssens

BACKGROUND & AIMS Impaired accommodation of the proximal stomach to a meal has been reported in functional dyspepsia, but its relevance to symptoms is unclear. The aim of this study was to test the hypothesis that impaired gastric accommodation causes early satiety. METHODS A gastric barostat was used to study postprandial fundus relaxation in 35 healthy subjects and 40 patients with functional dyspepsia. Gastric emptying, Helicobacter pylori status, sensitivity to gastric distention, and a dyspepsia symptom score were obtained from all patients. In addition, the effect of sumatriptan, a fundus-relaxing 5-hydroxytryptamine1 agonist, on gastric accommodation and on early satiety in dyspeptic patients was studied. RESULTS Impaired gastric accommodation to a meal was found in 40% of the patients. In univariate analysis, this was associated with early satiety and weight loss but not with hypersensitivity to gastric distention, presence of H. pylori, or delayed gastric emptying. In a multivariate analysis, only early satiety was associated with impaired gastric accommodation. Sumatriptan restored gastric accommodation, thereby significantly improving meal-induced satiety. CONCLUSIONS Impaired relaxation of the proximal stomach to a meal is present in a high proportion of patients with functional dyspepsia. It is associated with symptoms of early satiety. Restoring gastric accommodation with a fundus-relaxing drug improves early satiety.


Gut | 1999

An evidence-based appraisal of reflux disease management - The Genval Workshop Report

J. Brun; A. M. Fendrick; M. B. Fennerty; Jozef Janssens; Peter J. Kahrilas; K. Lauritsen; J. C. Reynolds; M. Shaw; Nicholas J. Talley

This report summarises conclusions from an evidence-based workshop which evaluated major clinical strategies for the management of the full spectrum of gastro-oesophageal reflux disease, with an emphasis on medical management. The disease was defined by the presence of oesophageal mucosal breaks or by the occurrence of reflux induced symptoms severe enough to impair quality of life. Endoscopy negative patients were recognised as the most common subgroup; most of these patients can be diagnosed by a well structured symptom analysis. There is a consistent hierarchy of effectiveness of available initial and long term therapies that applies for all patient subgroups. Lifestyle measures were judged to be of such low efficacy that they were rejected as a primary therapy for all patient subgroups. Proton pump inhibitor therapy was considered the initial medical treatment of choice because of its clearly superior efficacy which results in the most prompt achievement of desirable outcomes at the lowest overall medical cost. It was acknowledged that most of patients require long term management and that any maintenance therapy should be chosen by step down to the regimen that is still effective, but least costly. Endoscopic monitoring of routine long term therapy was considered inappropriate, on the basis that control of symptoms is an acceptably reliable indicator of healing in patients with oesophagitis. Laparoscopic antireflux surgery was recognised as a significant therapeutic advance, the results of which, however, depend substantially on the experience of the surgeon. There are currently no published direct comparisons of cost and efficacy outcomes of optimal medical and surgical therapies for reflux disease. To a significant degree, the choice between medical and surgical therapy should depend on informed patient preference. Substantial advances have occurred recently in the understanding and treatment of reflux disease. By contrast, there has been relatively little research into the best …


Journal of Clinical Investigation | 1977

The interdigestive motor complex of normal subjects and patients with bacterial overgrowth of the small intestine.

Gaston Vantrappen; Jozef Janssens; J Hellemans; Yvo Ghoos

Intraluminal pressures were measured in the gastric antrum and at different levels of the upper small intestine in 18 normal subjects to investigate whether or not the interdigestive motor complex, identified in several animal species, occurs in man and, if so, to determine its characteristics. In all normal subjects, the activity front of the interdigestive motor complex was readily identified as an uninterrupted burst of rhythmic contraction waves that progressed down the intestine and that was followed by a period of quiescence. Quantitative analysis of various parameters of the complex and simultaneous radiological and manometrical observations revealed that it resembled closely the canine interdigestive motor complex. To test the hypothesis that disorders of this motor complex may lead to bacterial overgrowth in the small intestine, similar studies were performed in 18 patients with a positive (14)CO(2) bile acid breath test and in an additional control group of 9 patients with a normal (14)CO(2) breath test. All but five patients had normal interdigestive motor complexes. The five patients in whom the motor complex was absent or greatly disordered had bacterial overgrowth as evidenced by (14)CO(2) bile acid breath tests before and after antibiotics. These studies establish the presence and define the characteristics of the normal interdigestive motor complex in man. They also suggest that bacterial overgrowth may be due to a specific motility disorder i.e., complete or almost complete absence of the interdigestive motor complex.


The American Journal of Gastroenterology | 2003

Symptoms Associated With Impaired Gastric Emptying of Solids and Liquids in Functional Dyspepsia

Giovanni Sarnelli; Philip Caenepeel; Benny Geypens; Jozef Janssens; Jan Tack

OBJECTIVES:The relationship between functional dyspepsia and delayed gastric emptying of solids or liquids is still unclear. The aim of the present study was to investigate in dyspeptic patients the prevalence of delayed gastric emptying for solids or for liquids and to investigate the relationship to the dyspepsia symptom pattern.METHODS:In 392 and 330 patients with functional dyspepsia, the solid and liquid gastric emptying, respectively, was measured using breath tests, and the severity of eight dyspeptic symptoms was scored.RESULTS:Gastric emptying of solids and liquids were delayed in 23% and 35% of the patients. Multivariate analysis showed that the presence of vomiting and postprandial fullness was associated with delayed solid emptying (OR 2.65, 95% CI = 1.62–4.35 and OR 3.08, 95% CI = 1.28–9.16, respectively). Postprandial fullness was also associated with the risk of delayed liquid emptying when symptom was present (OR 3.5, 95% CI = 1.57–8.68), relevant or severe (OR 2.504, 95% CI = 1.41–4.65), and severe (OR 2.214, 95% CI = 1.34–3.67). Severe early satiety was associated with the risk of delayed liquid emptying (OR 1.902, 95% CI = 1.90–3.30).CONCLUSIONS:A subset of dyspeptic patients has delayed gastric emptying of solids or of liquids. Delayed gastric emptying of solids was constantly associated with postprandial fullness and with vomiting. Delayed emptying for liquids was also associated with postprandial fullness and with severe early satiety.


Digestive Diseases and Sciences | 1979

Motilin and the interdigestive migrating motor complex in man.

Gaston Vantrappen; Jozef Janssens; T Peeters; Stephen R. Bloom; Nd Christofides; J Hellemans

In order to assess the possible role of the new candidate gut hormone, motilin, in cantrolling the interdigestive migrating motor complex (MMC) in man, 14 normal subjects were studied after an overnight fast by means of three pressure-recording catheters with orifices 25 cm apart in the upper small intestine. The typical aboral progressing bursts of pressure waves occurred at a mean interval of 137 minutes and were preceded by a peak motilin level 25 pmol/liter higher than the lowest level in the postactivity-front quiescent period. To study the effect of exogenous motilin, an infusion of pure porcine motilin at various dose levels was given to 16 normal volunteers shortly after the onset of the phase I quiescent period. Motilin infusion induced an activity front in 12 of the 16 subjects. The mean activity front interval was reduced to 46 min (P<0.001). This effect could be obtained tained even at the low dose level of 0.4 pmol/kg/min, which produced an increase in plasma motilin level of only 57 pmol/liter. These data suggest that a cyclic rise in plasma motilin levels is one of the factors involved in the production of the activity front of the migrating motor complex in man.


Gut | 2006

Influence of ghrelin on interdigestive gastrointestinal motility in humans

Jan Tack; Inge Depoortere; Raf Bisschops; Christine Delporte; B Coulie; Ann L. Meulemans; Jozef Janssens; T Peeters

Background: Recent studies in animals have shown that ghrelin stimulates upper gastrointestinal motility through the vagus and enteric nervous system. The aim of the present study therefore was to simultaneously investigate the effect of administration of ghrelin on upper gastrointestinal motility and to elucidate its mode of action by measuring plasma levels of gastrointestinal hormones in humans. Materials and methods: Nine healthy volunteers (four males; aged 22–35 years) underwent combined antroduodenal manometry and proximal stomach barostat study on two separate occasions at least one week apart. Twenty minutes after the occurrence of phase III of the migrating motor complex (MMC), saline or ghrelin 40 μg was administered intravenously over 30 minutes in a double blind, randomised, crossover fashion. Ghrelin, motilin, pancreatic polypeptide, glucagon, and somatostatin were measured by radioimmunoassay in blood samples obtained at 15–30 minute intervals. The influence of ghrelin or saline on MMC phases, hormone levels, and intraballoon volume was compared using paired t test, ANOVA, and χ2 testing. Results: Spontaneous phase III occurred in all subjects, with a gastric origin in four. Administration of ghrelin induced a premature phase III (12 (3) minutes, p<0.001; gastric origin in nine, p<0.05), compared with saline (95 (13) minutes, gastric origin in two). Intraballoon volumes before infusion were similar (135 (13) v 119 (13) ml; NS) but ghrelin induced a longlasting decrease in intraballoon volume (184 (31) v 126 (21) ml in the first 60 minutes; p<0.05). Administration of ghrelin increased plasma levels of pancreatic polypeptide and ghrelin but motilin, somatostatin, and glucagon levels were not altered. Conclusions: In humans, administration of ghrelin induces a premature gastric phase III of the MMC, which is not mediated through release of motilin. This is accompanied by prolonged increased tone of the proximal stomach.


Digestion | 2002

Gastric electrical stimulation in intractable symptomatic gastroparesis.

Thomas L. Abell; Eric Van Cutsem; Hasse Abrahamsson; Jan D. Huizinga; Jan W. Konturek; Jean Paul Galmiche; Guy VoelIer; Ludo Filez; Bernt Everts; William E. Waterfall; Wolfram W. Domschke; Stanislas Bruley des Varannes; Babajide Familoni; Ivan M. Bourgeois; Jozef Janssens; Gervais Tougas

Background: The treatment of gastroparesis remains unsatisfactory despite prokinetic and anti-emetic drugs. Gastric electrical stimulation has been proposed as a therapeutic option. We have assessed the effect of gastric electrical stimulation on symptoms, medical treatment, body weight and gastric emptying in patients with intractable symptomatic gastroparesis in a non-placebo-controlled study. Methods: In this multicenter study, 38 highly symptomatic patients with drug-refractory gastroparesis were enrolled. Patients first received temporary electrical stimulation using percutaneous electrodes. The 33 responders to temporary stimulation then underwent surgical implantation of a permanent stimulator. Severity of vomiting and nausea was assessed before and after stimulation. Patients were reassessed 3, 6, and 12 months after permanent implantation. Results: With stimulation, 35/38 patients (97%) experienced >80% reduction in vomiting and nausea. This effect persisted throughout the observation period (2.9–15.6 months, 341 patient-months). Gastric emptying did not initially change, but improved in most patients at 12 months. At 1 year, the average weight gain was 5.5% and 9/14 patients initially receiving enteral or parenteral nutrition were able to discontinue it. Conclusion: Electrical stimulation of the stomach has an immediate and potent anti-emetic effect. It offers a safe and effective alternative for patients with intractable symptomatic gastroparesis.


Gastroenterology | 1986

24-Hour recording of esophageal pressure and pH in patients with noncardiac chest pain

Jozef Janssens; Gaston Vantrappen; G Ghillebert

Sixty patients with anginalike chest pain of noncardiac origin were studied to determine the diagnostic value of 24-h ambulatory esophageal pH and pressure monitoring. The results of these 24-h studies were compared with those obtained by established methods, including x-rays, endoscopy with biopsy, conventional esophageal manometry, and acid perfusion test. Esophageal origin of the chest pain was considered to be likely if the familiar pain sensation was reproduced by the acid perfusion test, or if the pain occurred during an episode of gastroesophageal reflux, severe motor disorders, or both. When the results of established methods were combined and interpreted according to predetermined criteria, esophageal origin of the pain was shown to be likely in 27% of the patients. The 24-h recordings, alone, showed the esophagus to be the likely cause of the pain in 35% of the patients. Combination of all conventional examinations and of 24-h recordings made esophageal origin of the pain likely in 48% of the patients.


Gut | 1999

Patterns of gas and liquid reflux during transient lower oesophageal sphincter relaxation: a study using intraluminal electrical impedance

Daniel Sifrim; Jiri Silny; Richard H. Holloway; Jozef Janssens

Background Belching has been proposed as a major mechanism underlying acid gastro-oesophageal reflux in normal subjects. However, the presence of oesophageal gas has not been measured directly but only inferred from manometry. Aims To investigate, using intraluminal electrical impedance, the patterns of gas and liquid reflux during transient lower oesophageal sphincter (LOS) relaxations, the main mechanism of acid reflux in normal subjects. Methods Impedance changes associated with the passage of gas were studied in vitro, and in vivo in cats. Oesophageal manometry, pH, and intraluminal electrical impedance measurements were performed in 11 normal subjects after a meal. Results Gas reflux caused a sudden increase in impedance that propagated rapidly to the proximal oesophagus whereas liquid reflux induced a retrogressively propagated fall in impedance. Impedance showed gas or liquid reflux during most (102/141) transient LOS relaxations. When acid reflux occurred, impedance showed evidence of intraoesophageal retrograde flow of liquid in the majority (78%) of events. Evidence of gas retroflow was found in almost half (47%) of acid reflux episodes. When present together, however, liquid preceded gas on 44% of occasions. Overall, gas reflux occurred as the initial event in only 25% of acid reflux episodes. Conclusions These findings suggest that in upright normal subjects, although belching can precipitate acid reflux, most acid reflux occurs as a primary event.


Alimentary Pharmacology & Therapeutics | 2005

Influence of ghrelin on gastric emptying and meal-related symptoms in idiopathic gastroparesis.

Jan Tack; Inge Depoortere; Raf Bisschops; Kristin Verbeke; Jozef Janssens; Theo L. Peeters

Background : Ghrelin, the endogenous ligand of the growth hormone secretagogue receptor, is released from the stomach. Animal studies suggest that ghrelin stimulates gastrointestinal motor activity.

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Jan Tack

Katholieke Universiteit Leuven

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Gaston Vantrappen

Katholieke Universiteit Leuven

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Daniel Sifrim

Queen Mary University of London

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Rita Vos

Katholieke Universiteit Leuven

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Raf Bisschops

Katholieke Universiteit Leuven

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Philip Caenepeel

Katholieke Universiteit Leuven

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Joris Arts

Katholieke Universiteit Leuven

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Paul Rutgeerts

Katholieke Universiteit Leuven

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Pieter Vanden Berghe

Katholieke Universiteit Leuven

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T Peeters

Katholieke Universiteit Leuven

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