Chuan-Hao Lin

Gastric emptying using three different formulas in infants with gastroesophageal reflux.

Summary The role of delayed gastric emptying (GE) in the pathogenesis of gastroesophageal reflux (GER) in infants is controversial at present. GE has been shown to be altered by the composition and osmolality of the feedings. This prospective study was undertaken to assess the changes in the GE and the percentage of time GER was detected by scintigraphy using three different formulas on consecutive days in infants with GER. Twenty-eight infants under 1 year of age diagnosed to have GER by extended intraesophageal pH monitoring (pH being <4.0 for >5% of the duration of the test), underwent scintigraphy on three consecutive days using the same volume per single feeding of a casein-predominant, soy, or a wheyhydrolysate formula in a randomized order. The formulas were isocaloric. Gastric emptying and percentage of GER into the esophagus were estimated for 60 min following these feedings. Mean GER percent during the study was 20.39, 17.68, and 16.34 on casein-predominant, soy, and whey-hydrolysate formulas, respectively, and was not significantly different. Mean values of GE were 39.7%, 44.6%, and 48.5% on casein, soy, and whey formula, respectively. No significant difference in GE was also observed between casein-predominant and soy formula. However, a significant difference was observed (p < 0.05) on GE between casein-predominant and whey-hydrolysate feedings. Our data suggest that formula selection may be important in the treatment of conditions associated with delayed gastric emptying.

Induction of Gastric Ornithine Decarboxylase in Early Weaning Rats

Background/Aims: Early weaning has been shown to induce intestinal ornithine decarboxylase (ODC) activities and cell proliferation in rats. No information is available about the effect of early weaning on ODC activity in the stomach. Methods: Suckling rats were prematurely weaned on postnatal day 15 and followed through day 21. Oxyntic gland mucosa of stomach was obtained on postnatal days 15, 16, 18 and 21 (days 0, 1, 3 and 6 after early weaning) and assayed for ODC activity, DNA, protein and pepsinogen activity. α-Difluoromethyl ornithine (DFMO), a specific ODC inhibitor, was given orally to early-weaned pups and its resultant effects were assessed on days 1 and 6 after early weaning. Results: Stomach mucosal wet weight, DNA, protein and pepsinogen activities significantly increased on day 6 after early weaning. ODC activity increased on days 1, 3, and 6 after early weaning, with the highest increase (3-fold) on day 1 when compared to controls. The increases of ODC activity, DNA and protein contents as induced by early weaning were significantly suppressed when pups were exposed to DFMO. However, no suppression of pepsinogen activity was observed. Conclusions: Our study shows that early weaning induces ODC activity and functional growth in the stomach. Gastric ODC activity is essential in gastric mucosal growth processes but not in differentiation. The induction of stomach ODC may act as an early marker in the growth of stomach mucosa induced by early weaning in rats.

Increased colonic ornithine decarboxylase activity in inflammatory bowel disease in children.

The risk of colorectal carcinoma is increased inpediatric-onset inflammatory bowel disease (IBD). Thereis little information available regarding the colonicmucosal proliferative state in children with IBD. The aim of this study was to assesscolonic ornithine decarboxylase (ODC) activity, a markerof cell proliferation, in pediatric IBD patients. ODCactivity was assessed in colonic mucosa from 23 children (7 with ulcerative colitis, 9 with Crohnsdisease, and 7 controls) undergoing colonoscopicexamination. ODC activities were then compared withdegree of inflammation of biopsied samples. ODCactivities in patients with and without corticosteroidtreatment were also analyzed. The mucosal ODC activitiesof sigmoid colon and rectum were significantly higher(2.5- to 4-fold) in both ulcerative colitis and Crohns disease. The higher ODC activity wasassociated with increased mucosal inflammation.Moreover, treatment with corticosteroids decreased theODC activity. In conclusion, using ODC activities as a marker of cell proliferation, our resultssuggest that there is a higher colonic mucosalproliferative state in children with IBD. The increasedODC activities were associated with increased colonicmucosal inflammation. Colonic mucosal ODC activity mayprovide an additional parameter to access thetherapeutic efficacy of corticosteroid treatment inpediatric IBD patients.

Essential role for polyamine biosynthesis in thyroxine stimulated pancreatic development in neonatal rats

Administration of thyroxine to rat pups leads to precocious development of the pancreas. The role of ornithine decarboxylase (ODC) and polyamines in thyroxine-induced pancreatic maturation was examined. Rat pups (aged 5 days) were given daily subcutaneous injection of thyroxine (0.1 micrograms/g body wt.) until the day before death. Serial ODC activities were measured in pancreatic homogenates after 1, 2, 3, 4, 5, 6, 7 and 10 days of thyroxine treatment. There was a biphasic induction of ODC activities by thyroxine: an early peak appeared on day 2 of treatment followed by a decrease on day 4; a second peak was evident on day 5 and then a decrease to control values by day 7. Significant increases in tissue concentrations of putrescine and spermidine were observed concomitant with two peaks of ODC activity. Pancreatic amylase concentration, DNA and protein also showed a significant increase after thyroxine treatment. Difluoromethyl ornithine (DFMO), a specific ODC inhibitor, given orally (8% in drinking water) to nursing dams at postnatal day 5 for 5 days caused an 83% inhibition of pancreatic ODC activity in thyroxine-treated pups when compared to thyroxine-treated pups not exposed to DFMO. Concomitantly, the thyroxine-induced increases in pancreatic weight, protein and amylase activity were suppressed. Our results suggest that increases in ODC activities and polyamine levels are critical intermediary steps in the precocious induction of pancreatic development by thyroxine.

2001: Author Index for abstracts

Babyatsky, M.W. 272 Baffi, M.C. 273 Ball, A.J. 269 Ballinger, A.B. 273 Bantick, S. 254 Barbara, G. 254 Barrachina, M.D. 271 Beckett, E.A.H. 250 Beckmann, C. 254 Bellinger, L.L. 252 Bielanski, W. 270 Bielefeldt, K. 267, 274 Bilski, J. 262 Bischoff, S. 251 Bonaz, B. 274, 275 Bonior, J. 262, 273 Booth, C.E. 267 Bradley, J.M. 249 Brammer, M.J. 254 Brinkman, B. 264 Brodacz, B. 270 Brown, D.R. 271 Browning, K.N. 272 Bruijnzeel, A.W. 277 Brzozowski, T. 261, 270 Bueno, L. 274, 275 Burr, R.L. 276 Burton, D. 264

7069 Value of serologic markers in children with inflammatory bowel disease (ibd).

Peri-nuclear anti-neutrophil cytoplasmic antibodies (pANCAs) and anti- saccharomyces cerevisiae antibodies (ASCAs) are increasingly used by clinicians for evaluation of patients with IBD. Aim: This prospective study was to assess the accuracy of these antibodies in evaluating children with confirmed or suspected IBD. Methods: Two groups of patients: one with established diagnosis with ulcerative colitis (UC) or Crohns disease (CD) based on clinical, radiological, endoscopic and histopathologic standard criteria. Second group consisted of patients who were evaluated for possible IBD and found to have gastrointestinal non-IBD disorders and served as controls. Both groups had IBD first step serologic tests then were extended to IgG and IgA ASCAs and IgG ANCA in positive screens at Prometheus lab, San Diego, CA. Peri-nuclear location of IgG ANCA-positive samples were evaluated by indirect immunofluorescence staining and confirmed by its disappearance after deoxyribonuclease treatment. In group one there were 19 patients with UC (mean age 12.8) and 27 with CD (mean age 13.8), and in group two there were 6 controls (mean age 11.2yr). Results: See table Conclusions:IBD serological markers in children are helpful diagnostic tools to assist in the evaluation of patients with suspected IBD but should not avert the need for more definitive tests.

EARLY WEANING INDUCES JEJUNAL MUCOSAL CELL PROLIFERATION IN NEONATAL RATS.|[dagger]| 718

The cellular mechanisms of early weaning on intestinal development are not well established. To see if cell proliferation occurs in intestinal mucosa after early weaning, suckling rats were weaned precociously on postnatal day 15 and sacrificed 1, 2, 3, and 6 days after early weaning. Jejunal mucosa were assayed for ODC (ornithine decarboxylase), sucrase activities, protein and DNA contents. Jejunal cell proliferation was monitored by bromodeoxyuridine (BrdU) immunohistochemistry. The results demonstrated that increased jejunal ODC activity was the earliest cellular event to occur after early weaning. ODC increased at day 1 and peaked at day 3 (32-fold), followed by sucrase activity with increases at day 2 and peaked at day 3 (13-fold). The increase in BrdU immunostaining was seen at day 3. The increase of protein and DNA contents occurred at day 6. Serum corticosterone levels were increased on days 1 and 2 only. To explore if the intake of high carbohydrate rat chow was the causative factor, we also compared the induction of ODC activity in early weaned and fasted pups. Results showed that 1 day after early weaning ODC activity was not increased in the fasted group while the early weaned group showed 7-fold increase. These findings suggest early weaning stimulates jejunal cell proliferation as indicated by increased in both BrdU immunostaining and ODC activity. Increase in corticosteroid may be the trigger in the initial stage of the early weaning process but dietary factor also plays a role.