Biomedical subjects

A G Press

Publications and source records attributed to A G Press.

11 recordsLinked to original sources

PubMed1999

Inflammation does not decrease intraluminal pH in chronic inflammatory bowel disease.

Intestinal inflammation may influence intraluminal pH. Profiles of the gastrointestinal pH were evaluated in 15 patients with active Crohn's disease of the ileocecal area. In addition, five patients with moderate (1) or severe (4) ulcerative colitis were studied. Fifteen healthy subjects served as controls. Intraluminal pH of the different parts of the gastrointestinal tract was measured by a free-floating pH-sensitive telemetering capsule. A metal sphere was attached to the capsule for exact localization by a metal detector. Physiological patterns of pH were maintained throughout the gastrointestinal tract including the inflamed segments. Median pH in the terminal ileum of the patients with Crohn's disease was 7.5 vs. 7.7 and in the rectum in ulcerative colitis 7.8 vs. 7.2 in the controls. In conclusion, intraluminal pH is not decreased by inflammatory changes in Crohn's disease and ulcerative colitis, allowing eudragit-coated pH-controlled-release formulations of mesalazine to dissolve in diseased areas also.

Acid-Base Equilibrium↗

PubMed1998

Gastrointestinal pH profiles in patients with inflammatory bowel disease.

BACKGROUND: 5-Amino salicylic acid preparations are used in therapy for patients with inflammatory bowel diseases. The bioavailability of these drugs depends on their coating. AIM: To determine whether intraluminal pH is decreased by the presence of inflammation, thereby altering the release of 5-amino salicylic acid in the intestinal lumen. METHODS: Intraluminal gastrointestinal pH was measured by means of a radiotelemetry capsule in 12 healthy controls, in 12 patients with Crohn's disease (five with active disease), and in 11 patients with ulcerative colitis (seven with active disease). RESULTS: The median gastric pH values in the patient groups (Crohn's disease 2.4, range 1.5-4.1; ulcerative colitis 1.95, range 1.55-4.4) were significantly higher than those observed in the controls (1.55, range 0.95-2.6). In the small bowel and colonic segments, all the pH values of Crohn's disease patients were comparable to those of the controls, as were the pH values in the proximal small intestine and in the left colon in patients with ulcerative colitis. However, the latter group had higher pH values in the terminal ileum, the caecum and the right colon. Patients with active disease had comparable median gastrointestinal pH values to patients in remission. CONCLUSIONS: The luminal release of 5-amino salicylic acid might not be inhibited by low pH in patients with active inflammatory bowel diseases. This supports a safe disintegration of the slow release mesalazine preparations even in the presence of severe disease.

Adult↗

PubMed1995

Effect of lactose, lactulose and bisacodyl on gastrointestinal transit studied by metal detector.

AIM AND METHODS: To study the effect of 45 g lactose, 30 g lactulose and 10 mg bisacodyl on gastrointestinal transit in 30 healthy volunteers by metal detector and Hinton marker method. The first set of measurements were performed under standard conditions. In a second stage, transit was slowed to twice the original value by loperamide to simulate constipation conditions. RESULTS: Bisacodyl drastically accelerated small and large intestinal transit. Colonic transit was shortened to 23% and to 31% of control values, without and with loperamide. Bisacodyl increased stool weight and decreased stool consistency in all persons. Lactulose marginally shortened small intestinal transit (P = 0.08) but significantly increased stool weight and decreased stool consistency. The accelerating effect of lactose on small intestinal transit was abolished by loperamide. Lactose did not influence colonic transit, stool weight or stool consistency. Results of metal detector and Hinton marker method corresponded well (r = 0.75), the metal detector method measuring slightly shorter transit times than the Hinton marker method. CONCLUSIONS: With the dose chosen in this trial, lactose did not have any laxative effect in lactose tolerant persons. Laxative effect was mild with lactulose and most pronounced with bisacodyl.

Adult↗

PubMed1993

Azathioprine combined with prednisolone or monotherapy with prednisolone in active Crohn's disease.

BACKGROUND: The role of azathioprine (AZA) in the treatment of active Crohn's disease (CD) is still controversial. This study examined whether AZA combined with standard prednisolone therapy improved the therapeutic outcome compared with monotherapy with prednisolone. METHODS: Forty-two patients with a Crohn's Disease Activity Index (CDAI) of > 150 were randomized into two groups. Both received 60 mg of prednisolone daily in a tapering regimen to a maintenance dose of 10 mg. In addition, group 1 received 2.5 mg AZA/kg body wt and group 2 received a placebo over the whole study period of 4 months. RESULTS: At the end of the trial, 16 of 21 patients (76%) in group 1 were in remission (CDAI < 150), compared with 8 of 21 (38%) in group 2 (P = 0.03). The CDAI in group 1 dropped from 290 +/- 97 (SD) to 72 +/- 84 and from 285 +/- 110 to 155 +/- 105 in group 2. The differences between activity indices in groups 1 and 2 became statistically significant after 8 weeks. The average prednisolone dose per day was 20.9 mg in group 1 and 26.7 mg in group 2 (P = 0.02). No major side effects were observed in this study. CONCLUSION: The combination of prednisolone and AZA was superior to the treatment with prednisolone alone in active CD. Patients receiving AZA showed remission more frequently, more quickly, and with lower doses of prednisolone.

Adolescent↗

PubMed1993

Influence of senna, fibre, and fibre + senna on colonic transit in loperamide-induced constipation.

Retarded colonic transit and disturbed defecation are the most prominent pathophysiological mechanisms in constipation. Both may be influenced by bulking agents and by laxatives such as senna. Direct measurements of the influence of such substances on colonic transit are rare mainly because of technical problems. We measured gastric emptying, small and large intestinal transit in 24 healthy volunteers by a newly developed method employing a metal detector. Twelve persons taking a normal diet received loperamide in a dose sufficient to double the individual transit time. All subjects measured gastrointestinal transit time under normal conditions and with Sennatin containing purified sennosides 20 mg, Agiocur (30 g) as a fibre product containing 20 g Plantago ovata seeds/husks, or Agiolax (10 g) as a combination of 5.4 g P. ovata seeds/husks + 1.2 g senna pod with a sennoside content of 30 mg. Colonic transit was reduced by Sennatin and by Agiolax from 39 +/- 4 h to 17 +/- 3 h (p < 0.005). Agiocur did not influence colonic transit (39 +/- 3 h). Loperamide prolonged colonic transit from 27 +/- 0.7 to 72 +/- 12 h. This effect was abolished by Sennatin (30 +/- 5 h) and Agiolax (27 +/- 1 h) (p < 0.005), but not by Agiocur (64 +/- 13 h). The same effects were seen when right and left colonic transit were analyzed separately. Neither gastric emptying nor small intestinal transit were affected by either substance. All of the three study drugs increased stool weight significantly (p < 0.05). When stool frequency and consistency were compared, the effects were less clear.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1992

[The effect of food intake on the gastric emptying of gastric juice-resistant tablets and capsules].

To test the effect of food intake on gastric emptying of gastric juice-resistant drugs, emptying time of a 11 x 6 mm tablet and a 20 x 7 mm capsule was measured by means of a metal detector in 10 healthy persons (5 men and 5 women; mean age 25 [18-30] years) after fasting and after eating three main and three in-between meals. After fasting the tablets left the stomach after 78 +/- 18 min, the capsules after 60 +/- 16 min, while meal intake delayed emptying by a factor of 10 to 12 +/- 1.3 hours and 10 +/- 1.8 hours, respectively. The slightly shorter emptying time of capsules was statistically not significant. The results indicate that gastric juice-resistant tablets taken during day-time may, if several meals are eaten, accumulate in the stomach and then be emptied together at night. It is recommended that such drugs be taken in the fasting state in the morning and between meals, while avoiding in-between meals.

Adolescent↗

PubMed1992

[Spontaneous bacterial peritonitis].

Patients with liver cirrhosis and ascites suffer from spontaneous bacterial peritonitis (SBP) in up to 25%. The typical clinical signs are abdominal pain with tenderness and fever. 30% have no signs of peritonitis. Then clinical worsening, encephalopathy, rising serum creatinine levels, and therapy resistant ascites may be the only clinical features. SBP must be differentiated from bacterascites and culture negative neutrocytic ascites by the polymorphonuclear neutrophil (PMN) count in the ascites and the presence of positive culture results, which has prognostic implications. Gram negative rods from the colon play an important etiological role in SBP. Gastrointestinal bleeding, lack of serum complement, a low ascites protein and the extent of intrahepatic shunts predispose to SBP. Then, prophylaxis with the comparable drugs neomycin and norfloxacin is indicated. Coexisting encephalopathy has to be treated by the therefore effective neomycin. Otherwise, norfloxacin is the drug of choice because of better acceptance and lower costs. Chemical parameters of the ascites (pH value less than 7.4; LDH and lactate greater than serum levels; glucose less than 50 mg%) help to assess the severity of peritonitis. The course of ascitic PMN under therapy and the time of persisting positive cultures can discriminate SBP from secondary peritonitis. Antibiotics of choice are amoxicillin-clavulanic acid and cefotaxime. Short course therapy (5 days) is a effective as long course therapy (10 days). Today SBP is no more life-threatening because diagnosis, prophylaxis and therapy have improved. However, complication rate of patients with liver cirrhosis and ascites has not changed.

Anti-Bacterial Agents↗

PubMed1991

Effect of loperamide on jejunal electrolyte and water transport, prostaglandin E2-induced secretion and intestinal transit time in man.

Jejunal perfusion was performed in 12 healthy volunteers to evaluate the dose dependent effects of loperamide on intestinal absorption, stimulated secretion and transit. In 6 volunteers intestinal perfusion of the jejunal segment with isotonic NaCl solution was followed by addition of loperamide in increasing doses (2-8 mg.l-1). The volunteers were pretreated with 1 mg.l-1 prostaglandin E2 (PgE2) in the perfusate before addition of 4 mg.l-1 loperamide. Phenolsulphonphtalein (PSP) boluses (2 ml) were given to measure mean transit time (MTT). Loperamide 2 mg.l-1 converted the minor secretion after perfusion with the standard solution (water -145 ml.min-1, Na -0.09 and Cl -0.04 mmol.min-1) to absorption (water 0.93 ml.min-1, Na 0.23, Cl 0.25 mmol.min-1) within 15 min. Higher doses of loperamide did not increase absorption. The addition of PgE2 induced net secretion of water (-4.48 ml.min-1) and electrolytes (Na -0.57, Cl -0.51 mmol.min-1). Loperamide 4 mg.l-1 significantly diminished the PgE2-induced net secretion by approximately 50%. Loperamide dose dependently increased the MTT from 6 (2 mg.l-1) to 13.3 min (8 mg.l-1). MTT was still delayed 60 min after a wash out period (10.5 min). It is concluded that loperamide had a dual effect or intestinal activities stimulating absorption and prolonging intestinal transit time with rising doses.

Adolescent↗

PubMed1991

Gastric emptying of indigestible tablets in relation to composition and time of ingestion of meals studied by metal detector.

Enteric-coated tablets leave the stomach mainly during the interdigestive phase. Composition as well as time of ingestion of meals may influence their gastric emptying considerably. In 12 normal volunteers gastric emptying of a plastic tablet with a metal core was followed by a metal detector in relation to different compositions and various times of ingestion of meals. With an empty stomach and after ingestion of 250 ml water, the mean time for gastric emptying of the tablet was 38 +/- 11 min (mean +/- SEM) and 38 +/- 8 min. Two hundred fifty milliliters of milk (652 kJ) and a formula diet (1000 kJ) delayed gastric emptying time to 128 +/- 14 and 152 +/- 6 min, respectively (P less than 0.05). Breakfast (2200 kJ) further retarded gastric emptying compared with both liquids to 249 +/- 24 min (P less than 0.05). There was a close correlation between nutritive density and gastric emptying of the tablet (r = 0.92; P less than 0.001). Main meals also delayed gastric emptying of tablets when compared to empty stomach (P less than 0.05). A snack after breakfast further delayed gastric emptying from 201 +/- 10 to 278 +/- 19 min (P less than 0.05). The largest delay was observed following ingestion of breakfast, lunch, dinner, and additional snacks (509 +/- 220 min). We conclude that the delay of gastric emptying of enteric-coated tablets by food is related to its nutritive density and eating habits. The gastric emptying of an enteric coated tablet that is ingested early in the morning may be delayed until late at night when several meals and snacks are ingested during the day, leading to unwanted alterations in bioavailability and to possible adverse effects.

Adult↗

PubMed1990

Antibodies to cytoskeletal proteins in patients with Crohn's disease.

The immunologic basis of inflammatory bowel disease has been the focus of interest of a series of studies on Crohn's disease and the process of immune sensitization at the gastrointestinal mucosal level is functionally poorly understood. To date only few contradictory reports concerning the incidence of autoantibodies in patients with this disease exist. The aim of this study was to investigate the sera drawn from 60 patients suffering from biopsy-proven Crohn's disease to evaluate the prevalence of autoantibodies against nuclear antigens and cytoskeletal proteins. Using standard methods, no anti-nuclear antibodies or antibodies to extractable nuclear antigens could be detected. All sera were also negative for antibodies to double-stranded DNA, anti-mitochondrial antibodies, and antibodies to gastric parietal cells. Using sensitive enzyme-linke immunosorbent assays with purified antigens and Western blotting with cytoskeletal proteins of human intestinal cells, the following antibodies could be demonstrated: cytokeratin 18 autoantibodies (IgG 20.0%; IgM 6.7%; IgA 13.3%), actin antibodies (IgG 36.7%; IgM 48.3%, IgA 26.7%), desmin antibodies (IgG 6.7%; IgM 15.08%; IgA 5.0%), vimentin antibodies (IgG 3.3%; IgM 16.7%; IgA 10.0%) and tropomyosin antibodies (IgG 3.3%; IgM 3.3%, IgA 5.0%). Statistically significant correlations could be found for levels of cytokeratin 18 antibodies (IgM-type) and the BEST index of activity, and for levels of desmin antibodies (IgM-type) and the van HEES index of activity. Highest levels could be measured for actin antibodies (IgG-type) in patients with isolated disease manifestation in the colon. The mechanism of induction of autoantibodies against cytoskeletal components in Crohn's disease still remains obscure. Unmasking of hidden antigens after cell injury during the inflammatory process of disease might lead to sensitization and antibody production. The pattern of antibodies in patients with Crohn's disease seems to be different compared with that of connective tissue diseases.

Adolescent↗

PubMed1989

Gastrointestinal transit of undigestible solids measured by metal detector EAS II.

A new method was developed to measure gastrointestinal transit: a metal particle is followed on its way through the gastrointestinal tract by means of a portable metal detector. Deviation of measured localization of the metal particle from the exact site was 0.5-1.0 cm depending on its size and distance from the search probe. A metal sphere of 6 mm diameter can be located accurately in the body at a distance of 2-12 cm from the abdominal surface. Emptying of a metal particle from the stomach, its arrival at the caecal area and its passage through the colon into the rectum can be registered and hence, gastric residence time, small intestinal transit and transit through different parts of the colon were determined. Gastric residence time at the interdigestive phase was (mean +/- SD) 67 +/- 52 min in 20 persons with a range of 9-185 min. When gastric emptying was recorded by pH sensitive radiotelemetering capsule in 10 persons, correlation of both methods was r = 0.99. Small intestinal transit averaged 110 +/- 56 min in six healthy volunteers when breakfast was eaten after the marker had left the stomach. It was delayed to 218 +/- 34 min (P less than 0.01) when fasting was continued. Large intestinal transit of the metal marker was compared to whole body transit of radio-opaque ('Hinton') markers. In nine normal persons, 70% of the Hinton markers were excreted together with the metal particle. It is concluded that this new method is suitable for studying a large variety of physiological, pathophysiological and pharmacological questions concerning gastrointestinal transit.(ABSTRACT TRUNCATED AT 250 WORDS)

Digestive System Physiological Phenomena↗