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PubMed1989

[Intragastric pH determination as a screening test in the diagnosis of chronic atrophic gastritis].

A simple routine endoscopic screening test has been sought for the diagnosis of chronic atrophic gastritis. An endoscopic-bioptic study was therefore carried out on 850 subjects presenting consecutively at a Digestive Endoscopy Department with dyspeptic-pain symptomatology. In a first sample of 389 patients, 2 biopsies of the gastric body and 2 of the gastric antrum were carried out, independently of the endoscopically documented macroscopic picture. Atrophic changes were in this way encountered in 65 patients (16.7%). In a second group of 461 patients, intragastric pH was determined extemporaneously during endoscopy. pH was = or greater than the chosen threshold value (3.5) in 117 patients and less than this value in 344. In all subjects with pH greater than 3.5 and, by comparison, in 130 with pH less than 3.5 biopsy was carried out on the gastric mucosa, 2 biopsies of the body and 2 of the antrum. Using this approach it was possible to determine the presence of atrophic changes in the gastric mucosa in 57 of 117 (48%) and in 25 of 130 (20%) respectively. In total, chronic atrophic gastritis was diagnosed in 83 of 461 subjects (18%). This percentage is comparable to that observed in the frequency of chronic atrophic gastritis using the more demanding and less selective test of bioptic sampling indiscriminately for all patient. So, the straight-forward determination of intragastric pH in a sample of gastric juice taken during digestive endoscopy would appear to meet the criteria demanded for a screening test and its wider use is recommended in routine endoscopic practice.

Adolescent↗

PubMed2003

Evaluation of the anti-ulcerogenic activity of a dry extract of Maytenus ilicifolia Martius ex. Reiss produced by a jet spouted bed dryer.

We undertook the present study to evaluate the activity of the dried extract of Maytenus ilicifolia against stomach ulcers and in the increase of the volume and pH of the gastric juice of Wistar rats, as a model to evaluate the viability of the Jet Spouted Bed Dryer for the production of dry-extracts of medicinal Brazilian plants. The extract was obtained from the drying of a hydro-alcoholic extract with drying aid (40% of colloidal SiO2 related to solid content in the concentrated extract, at a concentration of 15.82% in water). The drying conditions employed were: Temperature of the spouting gas 150 degrees C, feed flow-rate of hydro-alcoholic extract 16.0 g/min, feed flow rate of the spouting gas 1.67 m3/min and static bed height 7.0 cm. Wistar rats received three different doses (140, 280 and 420 mg/kg) of the dried extract by intraperitoneal way and, after 60 minutes, were immobilized with wire screen and placed at temperature of 4 degrees C for two hours (cold-restraint stress). The animals were sacrificed and the stomach removed, examined and the volume and pH of the gastric secretion determined. A significant reduction in the ulceration index, was observed as well as a significant increase of the volume and of the pH of the gastric secretion for all doses administered. This is an indication that the preparation of dried extracts by the Jet spouted bed technique does not alter the biological activity of Maytenus ilicifolia.

Animals↗

PubMed1977

Participation of the jejunum and ileum in postprandial gastric secretion in man.

The role of the small intestine in postprandial gastric secretory function was determined in 6 normal volunteers by diverting chyme at the ligament of Treitz and comparing the results with those obtained in the same individuals when chyme was exposed to the entire small intestine. Because diversion of chyme caused a lesser gastric secretory response, it is concluded that the small intestine contributes appreciably to the magnitude of gastric secretory responses to meals.

Adult↗

PubMed1978

Serum group I pepsinogens and gastrin in relation to gastric H+ and pepsin outputs before and after subcutaneous injection of pentagastrin.

A conventional pentagastrin test was carried out in 25 patients with dyspeptic complaints, and gastric H+ and pepsin outputs were determined. Blood was drawn before the intubation and 5 and 30 min after subcutaneous injection of pentagastrin, and serum group I pepsinogens (PG I) and serum gastrin were determined by radioimmunoassay methods. A significant correlation was found between serum PG I, on the one hand, and basal gastric pepsin, output as well as pentagastrin-stimulated gastric H+ and pepsin outputs, on the other. Basal serum gastrin was also significantly correlated to pentagastrin-stimulated gastric pepsin output as well as to serum PG I. Pentagastrin failed to induce an increase in serum PG I during the first 30 min.

Adult↗

PubMed1997

[The pathophysiological basis of vagotomy in perforated duodenal ulcers].

Fractional intubation, intragastric pH-metry and other methods were used in complex examination of 107 patients who had perforated duodenal ulcers. The influence of surgical vagotomy upon the state of tissue blood flow was determined by means of polarography with a medicamentous vagotomy test. The medicamentous denervation was found to result in decreased blood supply of the acid-producing area and increased blood filling of the duodenum mucose. A conclusion is made that performing vagotomy is expedient after suturing the ulcer defect in patients having no diffuse purulent peritonitis.

Adult↗

PubMed2001

Gastric antral juxtamucosal pH in helicobacter pylori positive and negative dyspeptic patients.

Maintenance of gastric juxtamucosal pH at a stable near neutral value may be the cumulative effect of the various components of the mucosal defense system. In order to assess the effect of helicobacter pylori (HP) infection on mucosal defense, we measured the gastric antral juxtamucosal pH in 40 dyspeptic patients by using a flexible glass pH microelectrode which can be passed down the instrument channel of standard gastroscopes. HP status was determined using serology, culture, histology and urease test. We also investigated the relationship between juxtamucosal pH and the severity of antral HP infection. The mean antral juxtamucosal pH in 26 (65%) HP positive patients was 6.49 +/- 0.20 compared to 6.19 +/- 0.21 in 14 (35%) HP negative patients (p < 0.00001). Other factors like age, sex, duodenogastric reflux or presence of chronic duodenal ulcer did not significantly affect juxtamucosal pH (p > 0.05). Subset analysis of data on HP positive patients (n = 26) revealed no significant correlations between antral chronic gastritis anti-HP IgG titre and antral juxtamucosal pH (p > 0.05). This study shows that HP increases gastric antral juxtamucosal pH. This finding supports the suggested role of HP in producing hypergastrinaemia and gastric acid hypersecretion.

Adult↗

PubMed1987

[Functional and morphological changes in the stomach in irradiation of the para-aortic region].

Six assays were conducted in order to determine some functional and morphological parameters of the gastric mucosa in patients who underwent Co60 irradiations of the para-aortic area. Slight as well as marked morphological alterations were observed whereas the functional alterations were found to be marked in all cases. Basal gastric secretion and serum gastrin level showed a continuous reduction, however, in case of severe gastritis the stimulated secretion was increased. A possible correlation with increased tissue histamine levels is discussed.

Aorta, Abdominal↗

PubMed1975

Concentration of lidocaine hydrochloride in newborn gastric fluid after elective caesarean section and vaginal delivery with epidural analgesia.

Lidocaine concentrations were measured after vaginal delivery or Caesarean section with epidural anaesthesia in samples of maternal and umbilical blood and in newborn gastric contents. The pH of the gastric aspirate was also determined in a number of neonates. Gastric lidocaine concentrations were higher and the pH was lower after vaginal delivery in comparison to Caesarean section. A significant inverse correlation exists between gastric pH and gastric lidocaine concentration, Neonate gastric lidocaine concentration was significantly higher than in maternal or umbilical venous plasma after vaginal delivery, but not after Caesarean section. Due to these differences, gastric lavage for the treatment of neonatal lidocaine intoxication may be more beneficial in reducing foetal systemic local anaesthetic concentration after vaginal than after elective abdominal delivery.

Anesthesia, Epidural↗

PubMed1991

Twenty-four hour intragastric acidity and plasma gastrin concentration profiles in female and male subjects.

1. Simultaneous 24 h intragastric acidity and plasma gastrin concentration profiles were determined in 35 healthy young women and 96 healthy young men. 2. The females had a consistently lower median hourly intragastric acidity, and a higher median hourly plasma gastrin concentration, throughout the 24 h. 3. The 24 h integrated intragastric acidity was significantly lower in the female group (females, 485 mmol.h.l-1; males, 842 mmol.h.l-1. P less than 0.001). The 24 h integrated plasma gastrin concentration was significantly higher in the female group (females, 407 pmol.h.l-1; males, 185 pmol.h.l-1; P less than 0.001).

Adult↗

PubMed2005

Regional postprandial differences in pH within the stomach and gastroesophageal junction.

Our objective was to determine regional differences in intragastric pH after different types of meals. Ten normal subjects underwent 27-hr esophagogastric pH monitoring using a four-probe pH catheter. Meals were a spicy lunch, a high-fat dinner, and a typical bland breakfast. The fatty dinner had the highest postprandial buffering effect, elevating proximal and mid/distal gastric pH to 4.9 +/- 0.4 and 4.0 +/- 0.4, respectively, significantly (P < 0.05) higher compared to 4.2 +/- 0.3 and 3.0 +/- 0.4 for the spicy lunch and 3.0 +/- 0.3 and 2.5 +/- 0.8 for the breakfast. The buffering effect of the high-volume fatty meal to pH > 4 was also longer (150 min) compared to that of the spicy lunch (45 min) and the bland breakfast, which did not increase gastric pH to > 4 at any time. Proximal gastric acid pockets were seen between 15 and 90 min postprandially. These were located 3.4 +/- 0.8 cm below the proximal LES border, extending for a length of 2.3 +/- 0.8 cm, with a drop in mean pH from 4.7 +/- 0.4 to 1.5 +/- 0.9. Acid pockets were seen equally after the spicy lunch and fatty dinner but less frequently after the bland breakfast. We conclude that a high-volume fatty meal has the highest buffering effect on gastric pH compared to a spicy lunch or a bland breakfast. Buffering effects of meals are significantly higher in the proximal than in the mid/distal stomach. Despite the intragastric buffering effect of meals, focal areas of acidity were observed in the region of the cardia-gastroesophageal junction during the postprandial period.

Adult↗

PubMedDate not supplied

Digital image processing of intracellular pH in gastric oxyntic and chief cells.

Cytosolic pH (pHi) is a critically regulated determinant of intracellular function. Several mechanisms for pHi regulation in different tissues have been found, such as direct proton pumping, Na/H exchange, Cl/HCO3 exchange, NaHCO3 cotransport, and Na/H/Cl/HCO3 obligatorily linked. All these studies have used either single cells or cell populations assumed to be behaving homogeneously. Most tissues consist of more than one cell type, so it would be desirable to examine pHi regulation simultaneously in many identified individual cells, particularly in epithelia where disaggregation and purification of isolated cells destroys the normal distinction between luminal and serosal environments. We have used a pH-sensitive fluorescent dye, BCECF (2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein) and digital image processing to study pHi regulation simultaneously in the oxyntic cells (OC) and chief cells (CC) of gastric glands isolated from rabbit stomach. CCs become markedly more acidic upon removal of external Na (Nao), but pHi is restored rapidly on return to normal Nao, with or without Cl. Oxyntic cell pHi is much less affected by Nao. Conversely, OCs become strongly more alkaline on removal of external Cl (Clo), pHi being restored when Clo is replaced with or without Na, whereas CCs are relatively insensitive to Clo. Therefore, Na/H exchange is dominant over Cl/HCO3 exchange in CCs, but in the neighbouring OCs, Cl/HCO3 outweighs the Na/H mechanism, a heterogeneity that correlates with the functions of the two cell types.

Animals↗

PubMed1994

Dose effects of aspirin on gastric prostaglandins and stomach mucosal injury.

OBJECTIVE: To determine if a dose of aspirin exists that might inhibit thromboxane-dependent platelet function without causing gastric mucosal injury, we studied the effects of a wide range of doses of aspirin (3 mg/d to 2600 mg/d) on gastric juice prostaglandins (PGE2 and PGF2 alpha), on serum thromboxane B2, and on stomach mucosal injury as reflected by gastric juice hemoglobin and DNA concentrations. DESIGN: A randomized, placebo-controlled study. SETTING: Research laboratory at a Veterans Affairs medical center. PARTICIPANTS: 16 healthy volunteers (5 men and 11 women). INTERVENTION: In the first part of the study, volunteers received placebo; aspirin, 324 mg/d; 1300 mg/d; or 2600 mg/d for 2 days. In the second part, volunteers received placebo; aspirin, 3 mg/d; 10 mg/d; 30 mg/d; or 81 mg/d for 8 days. MEASUREMENTS: Gastric juice PGE2 and PGF2 alpha, hemoglobin and DNA concentrations; gastric juice volume and acidity; and serum salicylate and thromboxane B2 concentrations. RESULTS: In the first part, significant and similar (approximately 50%) inhibition of gastric juice prostaglandin output was observed with daily aspirin doses of 324 to 2600 mg. However, a significant increase in gastric juice hemoglobin output occurred only with 2600 mg/d. In the second part, significant inhibition (approximately 50%) of gastric PGE2 output was noted at a daily aspirin dose of 30 mg. Lower aspirin doses did not reduce PGE2 output significantly, although these doses did significantly reduce serum thromboxane B2 in a dose-related manner. CONCLUSIONS: Aspirin can significantly reduce serum thromboxane B2 at doses of 3 mg/d or 10 mg/d, which are significantly below the threshold dose for significant gastric prostaglandin inhibition and acute stomach mucosal injury.

Adult↗

PubMed1996

Is motility impaired in the entire upper gastrointestinal tract in patients with gastro-oesophageal reflux disease?

BACKGROUND: Although the pathogenesis of gastro-oesophageal reflux disease is multifactorial, abnormal function of the lower oesophageal sphincter has been established, and in some cases motility defects in the oesophageal body has been described. In some patients with gastro-oesophageal reflux disease delayed gastric emptying has also been observed. METHODS: Oesophageal and gastric motor function, as evaluated by use of scintigraphy and manometry, were studied concomitantly in 105 patients with chronic, gastro-oesophageal reflux disease before and after antireflux surgery. In a subgroup of these patients (n = 29) similar data were retrieved also at 2.7 years after antireflux surgery. RESULTS: Impaired oesophageal motor function expressed as delayed transit of a labelled bolus was closely associated with motor dysfunction also recorded in the stomach as determined by delayed emptying of labelled solid food items. A similar relationship was found when oesophageal motor dysfunction was characterized as the frequency of failed primary peristalses after water swallows during manometry. When the 105 patients were studied half a year after an antireflux operation, noncorrelation between oesophageal and gastric motor function could be recorded. CONCLUSIONS: These data further substantiate the view that gastro-oesophageal reflux disease is associated with a disturbed motor function within the entire upper gastrointestinal tract.

Adult↗

PubMed1990

Effects of ranitidine and metoclopramide on gastric fluid pH and volume in children.

To determine the effects of ranitidine and metoclopramide on gastric fluid in children, 40 healthy children (aged 2-8 yr) were allocated randomly to groups of 10 to receive one of four oral premedications 4 h before surgery: no premedication, metoclopramide 0.1 mg kg-1, ranitidine 2 mg kg-1 and metoclopramide 0.1 mg kg-1 with ranitidine 2 mg kg-1. After tracheal intubation, gastric fluid was aspirated and analysed for pH and total fluid volume. Ranitidine, with or without metoclopramide, increased gastric fluid pH significantly compared with control (P less than 0.05). Gastric fluid volume did not change significantly.

Child↗

PubMed1966

Studies on natural gastric flora. I. Bacterial flora of fasting human subjects.

The presence and survival of ingested micro-organisms, both pathogenic and commensal, is of practical interest because the stomach is one of the principal portals of entry of bacteria in humans. A study of the environmental factors governing the survival of indigenous flora in the gastric lumen will assist in determining whether potentially pathogenic organisms will survive in the stomach and pass on. The authors set out to determine the significance of gastric mucin in such survival, with the ultimate objective of learning what factors provide optimal bactericidal conditions.Samples of gastric juice were aspirated from 149 fasting individuals; samples of saliva, nose and throat swabs were also obtained. Positive gastric cultures were found in 82%. The study of the effects of gastric pH demonstrated an increase in the number of samples showing growth above pH 2.0 and a concomitant increase in total bacterial growth. At a pH lower than 2.0, certain organisms are selected out. It appears that even minor changes in gastrointestinal physiology disrupt the normal clearing of the flora.

Adolescent↗

PubMedDate not supplied

[Hydrochloric acid and pepsin secretion and the structure of the stomach in experimental protein malnutrition].

In adult male rats submitted during 12 weeks to a diet containing 2,5% protein the amount of hydrochloric acid and of pepsin was determined and the macro and microscopic morphology of the stomach was studied. A group fed a diet containing 20% protein was used as control. The statistical analysis of the data obtained showed that the apparent differences in the secretion of acid as well as pepsin could be attributed to the different body weights of the two groups. The morphological examination showed papillomas, frequently ulcerated occurring in the forestomach of the undernourished rats. In these areas, histological examination revealed hyperkeratosis and acanthosis. The glandular epithelium showed neither macroscopic nor microscopic alterations.

Animals↗

PubMed1985

Inhibition of peptic activity by sucralfate.

It is known that antacids containing aluminum hydroxide inhibit peptic activity by raising intragastric pH and by adsorbing pepsin. Since sucralfate contains aluminum hydroxide moieties, the possibility that this drug might inhibit peptic activity by these same mechanisms was examined. Sucralfate was incubated at a concentration of 10 mg/ml with samples of human gastric juice having pH values between 1.5 and 4 for 30 minutes at 37 degrees C. The proteolytic activity of the supernatant was then determined at a pH of 2.2 against a bovine hemoglobin substrate. When the initial pH of the gastric juice sample was 1.5, sucralfate was converted to a viscous gel and the pH of the incubation mixture rose to 2.9. However, there was no decrease in the peptic activity of the supernatant. In contrast, when the pH of the gastric juice sample was more than 2, the drug remained in suspension, but there was a graded rise in pH to a maximum of 4.1 and a progressive decrease in peptic activity (determined at a pH of 2.2) to a nadir of 65 percent of the control value. However, because peptic activity declines rapidly at a pH of more than 3, peptic activity at the ambient pH of the samples was reduced to only 25 percent of the control value. The results indicate that at pH values of more than 2, sucralfate inhibits peptic activity by both adsorbing pepsin and buffering hydrogen ions.

Adsorption↗

PubMed1986

[Bacterial flora in gastric juice taken at endoscopy in 93 normal subjects].

Bacteriologic examination of gastric juice samples taken during endoscopy in ninety-three subjects free of endoscopically-detectable disease was performed. Mucosal pH was determined using bromocresol green dye. Among the 17 subjects with a mucosal pH exceeding 4, 11 (64%) had more than 10(5) organisms/ml. In contrast, similar counts were found in only 10 of the 76 subjects with a normal mucosal pH. The pathogens recovered were normal hosts of the upper digestive tract and a few nitrate reductase + Enterobacteriaceae. Questions still to be resolved are whether these pathogens can induce disease and whether bacterial colonization correlates with the increased gastric nitrosamine levels and microscopic mucosal lesions previously described in patients with a gastric pH above 4.

Adult↗