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Biomedical subjects

J Janssens

Publications and source records attributed to J Janssens.

At least 109 records · Page 6Linked to original sources
PubMed1995

How well can quantitative 24-hour intraesophageal pH monitoring distinguish various degrees of reflux disease?

Twenty-four normal subjects and 64 symptomatic patients with various degrees of reflux disease (24 with reflux symptoms without esophagitis and 21 with mild and 19 with severe esophagitis) underwent quantitative 24-hr intraesophageal pH monitoring. Various reflux parameters during supine, interprandial, and postprandial periods were examined by binary logistic regression and by CART analysis to determine the sensitivity and specificity to separate the various groups of subjects and patients. The distinction was excellent between asymptomatic controls and patients with severe erosive esophagitis (sensitivity and specificity both 100% by logistic regression and 95% and 88%, respectively, by CART), but discrimination was poor when asymptomatic controls were compared to symptomatic patients without esophagitis (71% and 79% by logistic regression and 75% and 92% by CART), which is the most important indication for pH recording in clinical practice. A 3-hr postprandial pH recording was inadequate to distinguish the various groups. The acidity of the reflux episodes during the night appeared to be a crucial factor in the development of severe erosive esophagitis. The duration of esophageal acid exposure was another important factor in the development of reflux lesions.

Adolescent↗
PubMed1995

Provocation tests versus 24-h pH and pressure measurements.

The diagnosis of the oesophageal origin of non-cardiac chest pain is still a matter of controversy. This review discusses the diagnostic accuracy of oesophageal provocation tests, such as acid perfusion, edrophonium and balloon distension, in comparison with 24-h intra-oesophageal pH and pressure recordings. It also discusses how these various tests relate to known underlying mechanisms of oesophageal chest pain: acid reflux, oesophageal dysmotility or a combination of both.

Chest Pain↗
PubMed1995

A risk-benefit assessment of cisapride in the treatment of gastrointestinal disorders.

Cisapride is a substituted benzamide compound that stimulates motor activity in all segments of the gastrointestinal tract by enhancing the release of acetylcholine from the enteric nervous system. Cisapride is administered orally in the treatment of gastro-oesophageal reflux disease, functional dyspepsia, gastroparesis, chronic intestinal pseudo-obstruction syndromes and chronic constipation. In gastro-oesophageal reflux disease in both adults and children, cisapride provides symptomatic improvement and mucosal healing. Long term treatment with cisapride is effective in the prevention of relapse of oesophagitis. Cisapride improves gastric emptying rates and improves symptoms in patients with gastroparesis of various origins. Unlike domperidone and metoclopramide, long term administration of cisapride seems to result in persistently enhanced gastric emptying. Cisapride is also effective in improving symptoms in patients with functional dyspepsia. In comparative studies in patients with functional dyspepsia, cisapride was at least as effective as metoclopramide, domperidone, clebopride, ranitidine and cimetidine. Cisapride increases stool frequency and reduces laxative consumption in patients with idiopathic constipation. Severe cases of slow transit constipation seem refractory to cisapride. Clinical studies also indicate that cisapride might be effective in the treatment of chronic intestinal pseudo-obstruction, postoperative ileus, peptic ulcer and irritable bowel syndrome. Further clinical studies are warranted to define the role of cisapride in these conditions. The dosage of cisapride ranges from 5mg 3 times daily to 20mg twice daily. Cisapride is generally well tolerated, both during short and long term treatment. In children, cisapride is also well tolerated in doses of 0.2 to 0.3 mg/kg, 3 to 4 times daily.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Ulcer Agents↗
PubMed1995

The pathophysiology of gastro-oesophageal reflux disease: an overview.

Gastro-oesophageal reflux disease (GORD) is a multifactorial disease. Although it is primarily a motility disorder, several other disturbances can interfere and contribute to determine the severity of symptoms and the degree of lesions. In normal subjects, as in patients with pathological reflux, nearly all the episodes of reflux obey one of the following three mechanisms: (a) a transient complete relaxation of the lower oesophageal sphincter (TLOSR), (b) a transient increase in intra-abdominal pressure which overcomes the resistance of the antireflux barrier ('stress reflux') and, (c) a spontaneous reflux through a permanently hypotonic sphincter. Gastric distension is the major factor that can induce TLOSRs. Whereas, at rest, the diaphragm probably plays little role in cardial competence, diaphragmatic contraction may help prevent reflux in conditions resulting in increased abdominal pressure such as during physical activity and abdominal staining. The presence of a hiatal hernia increases susceptibility to reflux. A delayed gastric emptying may also facilitate reflux and represents a factor of resistance to antireflux therapy. Most studies in humans have shown that motor abnormalities remain unchanged after healing of oesophagitis. Acid and pepsin are the most noxious agents of the upper gastrointestinal secretions that can participate in the pathogenesis of oesophagitis. However, there is no evidence that patients with reflux have greater acid secretion than subjects without reflux. The clearance function is a two-stage phenomenon requiring first a reduction in volume by peristalsis and then chemical neutralization by saliva. Primary peristalsis is mainly responsible for the clearance of acid in both the upright and the supine positions. It takes longer to clear acid in patients with non-reducing hiatal hernia. The layer of mucus which carpets the mucosa comes from the saliva and also from the submucosal glands of the oesophagus. The paracellular pathway is the major route by which mucosal HCl enters and then damages the oesophageal epithelium. Only a minority of acid reflux episodes are accompanied by symptoms. The acid exposure during the time period that precedes a reflux episode (i.e. the acid burden) is a key factor determining whether that reflux episode will be symptomatic or asymptomatic.

Animals↗
PubMed1995

Intermittent subobstruction and cholestasis as complications of duodenal amyloid tumours.

Amyloidosis confined to the duodenum is uncommon. In the present report the history of an 83-year old patient, admitted for vomiting and heavy epigastric pain, is described. Radiographic and endoscopic investigation revealed two polypoid lesions in the duodenum (D2). Biopsies showed diffuse amyloid deposition in the lamina propria, muscularis mucosae and submucosa of the duodenum as well as vascular deposits. No other localisations were documented. Amyloid tumours of the gastrointestinal tract are rare but may lead to serious symptoms.

Aged↗
PubMed1994

Failing deglutitive inhibition in primary esophageal motility disorders.

BACKGROUND/AIMS: Primary esophageal motility disorders (achalasia, diffuse esophageal spasm, and intermediate forms) are suggested to be caused by different degrees of inhibitory dysfunction; however, direct evidence for this hypothesis has never been presented in humans. The aim of this study was to measure the degree of inhibition that precedes deglutitive contractions in patients with primary motility disorders. METHODS: Deglutitive inhibition was examined in patients with primary motility disorders: 9 with achalasia, 6 with symptomatic diffuse esophageal spasm, and 5 with intermediate forms. An artificial high-pressure zone was created in the esophageal body by inflating a balloon to a critical level, and pressure changes were measured at the interface between the balloon and esophageal wall. Inhibition was visualized as a relaxation of the artificial high-pressure zone. RESULTS: An inverse relationship was found between the degree of inhibition and the propagation velocity of the deglutitive contraction (r = 0.75; P < 0.001). Normally propagated contractions were preceded by an inhibition of 84.2% +/- 3.6%; fast-propagating contractions were preceded by partial inhibition of 40.6% +/- 6.2%; and, in case of simultaneous contractions, inhibition was absent, i.e., 2.6% +/- 1.6%. CONCLUSIONS: The spectrum of primary motility disorders is an expression of a progressively failing deglutitive inhibition.

Adult↗
PubMed1994

Comparison of the effects of midecamycin acetate and azithromycin on gastrointestinal motility in man.

The gastrointestinal motor effects of the macrolide antibiotic, azithromycin, were compared with those of midecamycin acetate. The method of investigation consisted of intraluminal pressure measurements in the gastric antrum and upper small intestine by means of a low compliance perfused catheter system. Eleven healthy volunteers participated in the single blind, placebo-controlled study of both interdigestive and postprandial gastrointestinal motility. Azithromycin was administered by mouth in a single 500 mg dose or in two daily doses of 250 mg; midecamycin acetate was given in a dose of 600 mg b.i.d. The effect of midecamycin acetate on gastric antral and jejunal motility was not significantly different from that of placebo. This was true for both the interdigestive and the postprandial phases of gastrointestinal motility. Peroral treatment with azithromycin resulted in a statistically significant increase in the postprandial antral motility index as compared to placebo. This increase was observed in the distal antrum as well as in the proximal antrum. In addition, the gastric contractions were found to originate higher up in the stomach after azithromycin as compared to placebo or midecamycin acetate.

Adult↗
PubMed1993

U.S. householder survey of functional gastrointestinal disorders. Prevalence, sociodemography, and health impact.

Our objective was to obtain national data of the estimated prevalence, sociodemographic relationships, and health impact of persons with functional gastrointestinal disorders. We surveyed a stratified probability random sample of U.S. householders selected from a data base of a national market firm (National Family Opinion, Inc.). Questions were asked about bowel symptoms, sociodemographic associations, work absenteeism, and physician visits. The sampling frame was constructed to be demographically similar to the U.S. householder population based on geographic region, age of householder, population density, household income, and household size. Of 8250 mailings, 5430 were returned suitable for analysis (66% response). The survey assessed the prevalence of 20 functional gastrointestinal syndromes based on fulfillment of multinational diagnostic (Rome) criteria. Additional variables studied included: demographic status, work absenteeism, health care use, employment status, family income, geographic area of residence, population density, and number of persons in household. For this sample, 69% reported having at least one of 20 functional gastrointestinal syndromes in the previous three months. The symptoms were attributed to four major anatomic regions: esophageal (42%), gastroduodenal (26%), bowel (44%), and anorectal (26%), with considerable overlap. Females reported greater frequencies of globus, functional dysphagia, irritable bowel syndrome, functional constipation, functional abdominal pain, functional biliary pain and dyschezia; males reported greater frequencies of aerophagia and functional bloating. Symptom reporting, except for incontinence, declines with age, and low income is associated with greater symptom reporting. The rate of work/school absenteeism and physician visits is increased for those having a functional gastrointestinal disorder. Furthermore, the greatest rates are associated with those having gross fecal incontinence and certain more painful functional gastrointestinal disorders such as chronic abdominal pain, biliary pain, functional dyspepsia and IBS. Preliminary information on the prevalence, socio-demographic features and health impact is provided for persons who fulfill diagnostic criteria for functional gastrointestinal disorders.

Absenteeism↗
PubMed1993

5-hydroxytryptamine-3 receptors are involved in the initiation of gastric phase-3 motor activity in humans.

BACKGROUND: 5-hydroxytryptamine-3 (5-HT3) receptor antagonists inhibit gastric phase-3 motor activity in the dog. This study examined the role of 5-HT3 receptors in the generation of gastric phase 3 of the migrating motor complex in humans. METHODS: Interdigestive motor activity was recorded manometrically in 16 subjects before and after administration of ondansetron, a selective 5-HT3 receptor antagonist. Plasma motilin values were also assayed in 7 individuals. The incidence of gastric activity fronts before and after ondansetron was compared with a control group that had not received ondansetron. The ability of erythromycin to induce a gastric activity front in the presence of ondansetron was also evaluated in 7 subjects. RESULTS: The incidence of gastric activity fronts was 69% before ondansetron vs. 19% after ondansetron. In contrast, in the control group there was no significant change in the incidence of gastric activity fronts over time. Activity fronts preceding ondansetron were associated with motilin peaks while activity fronts after ondansetron were not. Despite the previous administration of ondansetron, erythromycin induced gastric activity fronts in 89% of cases. CONCLUSIONS: Selective antagonism of 5-HT3 receptors suppresses the gastric component of phase-3 motor activity and simultaneously suppresses plasma motilin peaks. The results suggest that the suppression of gastric activity fronts is achieved via the suppression of plasma motilin peaks because in the presence of ondansetron a motilin agonist like erythromycin restores the gastric phase 3.

Adult↗
PubMed1993

Recurrent meningococcal infections in a patient with congenital C5 deficiency.

A congenital C5 deficiency was the cause of recurrent meningococcal disease in a 27-year-old man. The lack of serum bactericidal activity accounts for the higher incidence and the different course of Neisseria infections in patients with a deficiency of the late complement components. Early antibiotic treatment and vaccination with a capsular polysaccharide meningococcal vaccine (A,C,Y,W-135) should be considered.

Adult↗
PubMed1993

Bursts of non-deglutitive simultaneous contractions may be a normal oesophageal motility pattern.

The frequency and characteristics of non-deglutitive motor activity of the human oesophagus and its relation to motility patterns in the antrum and upper small intestine were studied in 25 fasted healthy subjects. Motility of the oesophagus, antrum, and upper small intestine was recorded by means of a manometric perfused catheter system. The most striking non-deglutitive motility pattern consisted of repetitive bursts of non-sequential pressure peaks occurring in the smooth muscle portion of the oesophagus. The mean number of pressure peaks per burst was 2.7 (SD 2) waves with a mean amplitude of 19.5 (SD 9.9) mm Hg and a duration of 3.09 (SD 0.22) seconds. The highest amplitude was 80 mm Hg and the longest burst consisted of 13 repetitive waves. The bursts were recorded up to a distance of 15-20 cm above the lower oesophageal sphincter. Ninety five per cent of the bursts occurred during a 15 minute period before the onset of phase 3 of the migrating motor complex in the antral or upper small intestinal area, or during the lower oesophageal sphincter component of the migrating motor complex. In conclusion, spontaneous bursts of non-sequential pressure peaks occurred in the smooth muscle part of the human oesophagus in relation to phase 3 of the migrating motor complex. They represent the oesophageal body component of phase 3 of the migrating motor complex and are not a sign of oesophageal motor abnormalities.

Adult↗
PubMed1993

Vaginal symptoms of unknown aetiology: a study in Dutch general practice.

Vaginal symptoms are frequently presented by women to general practitioners. In many cases, the aetiology of these symptoms remains unknown. This study focused on the factors associated with microbiologically unexplained vaginal symptoms, the course of symptoms and signs in these cases, and factors modifying this course. In a group of 610 women presenting to their general practitioner with vaginal symptoms (itching, irritation, abnormal but non-bloody discharge) the distribution of diagnoses was studied and factors associated with symptoms of unknown aetiology were identified using logistic regression analysis. During a three month follow up, the course of symptoms and signs was studied in 139 women with unexplained vaginal symptoms, using survival analysis methods. It was found that 25% of all the women had symptoms of unknown aetiology. A larger number of these women, compared with women with other diagnoses, were Caucasian, married, more highly educated, used oral contraceptives and reported psychological distress. During the follow-up period, a specific infection was diagnosed in less than 20% of the women with unexplained vaginal symptoms. Over half of the women (54%) recovered within three months. Short duration of symptoms before presentation was associated with a higher probability of recovery. From the study, it was found that many women visiting the general practitioner for vaginal symptoms had no demonstrable microbial disorder. Often these symptoms were transient and disappeared without intervention. Persistent symptoms may call for further examination where somatic, as well as psychosocial, factors should be taken into account.

Adolescent↗
PubMed1992

Relation between slow-wave frequency and spiking activity during the migrating myoelectric complex in dogs.

The quantitative relation between slow-wave periods and spiking activity was evaluated in vivo in canine small intestine during the fasted state. Experiments were performed in three conscious dogs with three bipolar electrodes, implanted respectively 10, 25 and 40 cm beyond the ligament of Treitz. Digitized electrical recordings were automatically processed for the individual slow-wave periods and spike-burst intensities using a set of computer programs developed in our laboratory. A linear correlation existed between the degree of spiking activity and the average length of the preceding slow-wave period. The slopes of the regression lines were less steep for more distal electrodes. A second series of experiments showed that an increase in the slow-wave period precedes the onset of phase 3 of the migrating myoelectric complex and that a fall in slow-wave period precedes the end of phase 3. These data show that a low slow-wave frequency is accompanied by a facilitation of spiking activity, whereas shortening of the slow-wave period is accompanied by a decrease in spike burst intensity. This relation between slow-wave period and spiking activity shows an aboral trend that may be related to intrinsic slow-wave frequency.

Animals↗