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T Tomomasa

Publications and source records attributed to T Tomomasa.

At least 55 records · Page 3Linked to original sources
PubMed1995

Gastrointestinal manometry findings in a case with dilated small bowel and disturbed transit treated successfully with bowel plication.

We report the manometric findings in a case of dilated small bowel and disturbed transit successfully treated with plication of the dilated small bowel. The female newborn infant required total parenteral nutrition following an operation for small bowel atresia. X-ray showed a dilated proximal small bowel. Jejunal manometry showed normal phase 3 migration but persistently low-amplitude contractions in the dilated segment. After plication of the dilated intestine, symptoms of bowel obstruction disappeared. A second manometry two weeks after the operation showed contractions with normal amplitude. These findings indicate that: (1) disturbed transit in the dilated intestine proximal to small intestinal atresia is associated with persistently low contraction amplitude, and (2) the amplitude can be increased by the plication of the dilated loop.

Digestive System↗
PubMed1995

Cytolytic action of stored human milk on blood cells in vitro.

Stored human milk induced cytolysis on various types of blood cells depending on the storage time and temperature. When separated by centrifugation after storage for 24 h at 4 degrees C, the cream, not whey, induced cytolysis. When separated and heated for 30 min at 56 degrees C before storage, neither cream or whey induced cytolysis. When the cream was heated at 56 degrees C for 30 min and mixed with non-heat-treated whey before being storage for 24 h at 4 degrees C, it induced cytolysis. When bile salt was added to whole milk before storage, the cytolytic activity was enhanced. When eserine was added, the cytolytic activity was suppressed. Thin layer chromatography showed that stored milk, not fresh milk, contained free fatty acids which caused a similar degree of cytolysis as stored whole milk. These results indicated that the cytolysis is due to the free fatty acids which were produced from triglycerides catalyzed by the lipase in milk.

Animals↗
PubMed1994

Effect of erythromycin on antroduodenal motility in children with chronic functional gastrointestinal symptoms.

To evaluate the effects of erythromycin on antroduodenal motility in children with chronic functional gastrointestinal symptoms, we studied 35 consecutive subjects referred for diagnostic motility studies. We recorded fasting motility for > 4 hr, then infused in random order either 1 or 3 mg/kg erythromycin intravenously over 1 hr and continued the study for another hour. Erythromycin induced phase III in 18 of 20 children who had phase III during fasting compared to only one of 15 who did not (P < 0.001). The antral motility index increased after erythromycin (1596 +/- 323 vs 436 +/- 242 mm Hg/30 min before erythromycin, P < 0.005) but the duodenal motility index did not change. The antral motility index was greater in children receiving 3 mg/kg than in those receiving 1 mg/kg (1968 +/- 391 vs 1226 +/- 285 mm Hg/30 min, P < 0.01), but duodenal motility indices did not differ. Only one child receiving the lower dose erythromycin complained of abdominal pain, nausea, or vomiting vs 9 of 19 the children receiving the higher dose (P < 0.02). In summary, in children with chronic functional gastrointestinal disorders, erythromycin rarely induced phase III in patients who did not have it during fasting. When different doses erythromycin are compared, 1 and 3 mg/kg are equally efficacious in inducing phase III episodes; the lower dose is associated with fewer side effects and the higher dose produces a higher antral motility index.

Adolescent↗
PubMed1994

Antroduodenal manometry in children and adults with severe non-ulcer dyspepsia.

BACKGROUND: Nonulcer dyspepsia is common in adults but has been recognized only recently in children. METHODS: We compared signs, symptoms, and antroduodenal motility findings in 34 children and 35 adults with severe nonulcer dyspepsia. RESULTS: Symptoms and signs were similar in the two groups. Ten children (29%) and one adult (3%) required tube feedings (p = 0.01). Abdominal surgery had been performed on 6 of 34 (18%) children and 18 of 35 adults (51%) (p < 0.01), without relief of symptoms. Esophageal manometry was abnormal in 5 of 23 (22%) children and 6 of 31 (19%) adults. Antroduodenal manometry was suggestive of neuropathy in 25 children and 26 adults and of myopathy in 3 children and 2 adults. Absence of phase 3 of the migrating motor complex was found in 4 children and 17 adults (p = 0.01). Antroduodenal manometry was normal in six children and seven adults. CONCLUSION: Signs, symptoms, and discrete manometric abnormalities of childhood nonulcer dyspepsia resembled those of adult nonulcer dyspepsia. Manometric findings in nonulcer dyspepsia resembled those reported in chronic intestinal pseudo-obstruction, suggesting that these conditions are on a continuum of enteric neuromuscular diseases.

Adolescent↗
PubMed1993

Erythromycin increases gastric antral motility in human premature infants.

The aim of this study was to determine if erythromycin (EM), which is a potent motilin agonist, alters gastrointestinal motility in premature infants. Six infants who were born after 23-30 weeks gestation and weighed 825-1,408 g at birth were studied when 6-31 days old. Intraluminal pressure changes within the gastric antrum and proximal duodenum were recorded. We infused EM 0.75 mg/kg intravenously for 15 min and we compared gastric and duodenal contractions for 30 min between before and after the initiation of EM infusion. In these preterm infants the migrating complex was not present, and was not induced by EM. However, in all 6 infants EM increased nonpropagating antral clusters of contractions (p < 0.05). The antral motility index increased 4-fold (p < 0.05). We concluded that human premature infants have functioning motilin receptors.

Duodenum↗
PubMed1993

Postnatal changes in receptor-mediated rabbit gastric smooth muscle relaxation.

The aims of this study were to identify mediators of relaxation in rabbit proximal gastric circular smooth muscle and to assess age-dependent changes in tissue response. Vasoactive intestinal peptide (VIP), adenosine, and norepinephrine induced tetrodotoxin-insensitive, concentration-dependent relaxation in bethanechol-precontracted (3 microM) gastric muscle strips from newborns and weanlings. Maximally effective concentrations of 10 microM VIP induced complete relaxation in newborns, but only 30% relaxation in weanlings (p < 0.01). Maximally effective concentrations of adenosine induced complete relaxation at both ages. Adenosine (ED50 3 microM) was more potent than adenosine triphosphate, indicating the presence of P1 purinergic receptors. In newborns norepinephrine induced complete relaxation (ED50 0.5 microM). The response to norepinephrine changed in age-dependent increments from relaxation in newborns to strong contraction in weanlings. In weanlings phentolamine inhibited norepinephrine-stimulated contraction, revealing persistent propranolol-sensitive relaxation. Tetrodotoxin and atropine had no effect on norepinephrine-stimulated contraction. In summary, in rabbit gastric circular smooth muscle: (1) VIP, adenosine, and norepinephrine induce relaxation; (2) VIP loses efficacy with age; (3) there is a beta-adrenergic receptor mediating relaxation in the newborn which persists, and (4) an alpha-adrenergic receptor mediating contraction emerges early in postnatal life. Age-dependent changes in response to VIP and norepinephrine may contribute to the postnatal maturation of the gastric motility.

Adenosine↗
PubMed1993

Predicting the clinical response to cisapride in children with chronic intestinal pseudo-obstruction.

We assessed upper gastrointestinal anatomy and function with contrast radiology and antroduodenal manometry in 51 children with chronic intestinal pseudo-obstruction (CIP) prior to entering these patients into an open-label outpatient trial of cisapride. The diagnosis of CIP was based on characteristic symptoms requiring special nutritional support (parenteral in 30, tube feeding in 12) or interfering with daily activities (documented by diary in nine). At a time the subjects were not acutely ill, antroduodenal pressures were recorded for > 4 h fasting and > 1 h after a complex liquid meal. Results were categorized by the most prominent manometric abnormality as myopathy (n = 6), absent migrating motor complex (MMC) (n = 27), failure to induce fed pattern (n = 7), MMC plus discrete abnormalities (n = 7), and postprandial duodenal hypomotility (n = 4). Patients in the first two categories did not have effective MMCs, but those in the last three categories did. Compared to children without MMCs, those with MMCs rarely required parenteral nutrition (p < 0.001). All children were treated with oral cisapride 0.2 mg/kg/dose t.i.d., and evaluated every 2 months for up to 1 yr. Of 49 evaluable subjects, the final global assessment was unchanged in 25, fair (improved symptom score) in 17, or excellent (change from TPN to tube feeding or tube feeding to oral feeding) in seven. Children with MMCs (13 of 18) responded more often to cisapride than those without MMCs (11 of 31), p < 0.02. All four subjects with postprandial duodenal hypomotility had excellent responses. Children with normal diameter bowel responded more often than those with dilated bowel, p < 0.004. To summarize, in children with CIP, absence of the MMC was associated with need for greater intensity of nutritional support and decreased response rate to cisapride. The response to cisapride was highly variable within the study group, but often could be predicted by the presence or absence of bowel dilation and MMCs.

Child, Preschool↗
PubMed1992

Effect of cell culture on rabbit colonic smooth muscle bradykinin receptors.

The aim of this study was to assess the effect of cell culture on the bradykinin receptor of rabbit colon myocytes. In longitudinal muscle strips prepared from distal colon, bradykinin stimulated dose-dependent contraction that was 62% of the maximal response to bethanecol. At 4 degrees C, [3H]bradykinin binding to fresh muscle homogenates from the distal colon was time dependent, saturable, and linearly related to tissue concentration. Specific binding of 0.6 nmol/L [3H]bradykinin was 80% +/- 2% of total binding. In competitive binding studies, Hill coefficients approached unity, suggesting the presence of a single class of receptors. The order of potency was bradykinin greater than [D-Phe7]bradykinin much greater than des-Arg9, [Leu8]bradykinin, which is consistent with results of a B2 receptor subclass. Colon myocytes from the longitudinal muscle layer achieved confluence and were harvested for studies after 12-14 days in culture. Bradykinin receptors were of high affinity [disassociation constant (Kd) = 672 pmol/L] and numbered 10,217 +/- 2567/cell. To show that the receptors on cultured myocytes were functional, the effect of bradykinin was measured (a) on intracellular calcium concentration using Fura 2 and (b) on prostaglandin E2 concentration in the culture media using radioimmunoassay. In cells grown to confluence on cover slips and preloaded with Fura 2, bradykinin stimulated the threshold response at 1 nmol/L and maximal response (increased intracellular calcium concentration from 229 to 633 nmol/L) at 1 mumol/L. Bradykinin, 100 nmol/L, increased Prostaglandin E2 in the culture media threefold. In summary, colon myocytes express functioning bradykinin receptors, which, unlike muscarinic receptors, persist in culture. Bradykinin appears to be a suitable agonist for studies of receptor-mediated intracellular events in cultured colon myocytes.

Animals↗
PubMed1992

Postnatal changes in the substance P receptor on rabbit gastric smooth muscle.

We used radioligand binding to tissue homogenates and isometric contraction of muscle strips to characterize the substance P (SP) receptor on gastric smooth muscle from 1- (newborn) and 7-day-old and 4- and 11-wk-old (weanling) rabbits. Scatchard analysis for newborns was curvilinear, suggesting the presence of multiple binding sites. In newborns the dissociation constant (Kd) of high-affinity binding site was 2.2 +/- 0.3 nM, and the maximum binding (Bmax) was 0.57 +/- 0.06 pmol/mg DNA. The number of high-affinity binding sites decreased with age, disappearing by 11 wk. The Kd for the low-affinity site was more than two orders of magnitude greater than that of the high-affinity site. In competitive binding studies with [3H]SP, the order of potency for the neurokinins was SP much greater than neurokinin A (NKA) greater than neurokinin B (NKB), suggesting that the high-affinity binding sites were NK-1 receptors. [125I]NKA is also bound to newborn tissue homogenate with high affinity. With [125I]NKA the order was NKA greater than SP greater than NKB, suggesting that NK-2 receptors were also present. In contraction studies, atropine and tetrodotoxin had no effect on tachykinin-stimulated contraction, suggesting solely myogenic tachykinin effects on this tissue. In newborn rabbits, the potency and efficacy of SP and NKA were similar. The half-maximal effective dose (ED50) of SP was nearly two orders of magnitude less in newborn rabbits than in weanlings; the potency of NKA did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1992

Developmental changes in gastric mucus gel thickness: responsiveness to 16,16-dimethyl prostaglandin E2 and mucosal protection in the rat.

The gastric mucosa of newborn rats is sensitive to the damaging effects of acid and ethanol. We measured gastric mucus gel thickness in newborn, suckling, and weaned rats by inversion microscopic observation. The thickness in newborn rats was 52.2 +/- 6.7 microns and increased with age, reaching 96.8 +/- 5.6 microns in 8-wk-old rats (p less than 0.001). Oral administration of 16,16-dimethyl prostaglandin E2 at concentrations of 10 and 100 micrograms/kg body weight increased mucus thickness in 8-wk-old rats but had no effect in 1-wk-old rats. We also assessed the effect of 16,16-dimethyl prostaglandin E2 on the prevention of gastric mucosal damage induced by ethanol. Oral 16,16-dimethyl prostaglandin E2 reduced damage in 8-wk-old rats, but there was no effect in 1-wk-old rats. These data suggest that the susceptibility of newborn rats to gastric mucosal injury may be related to the relative thinness of the gastric mucus gel layer and the failure of prostaglandins to increase the mucus gel layer thickness.

16,16-Dimethylprostaglandin E2↗
PubMed1991

The role of the accessory pancreatic duct of Santorini in pancreatic drainage in children (with emphasis on choledochal cyst patients).

Pancreatic drainage patterns have been studied by endoscopic retrograde cholangiopancreatography (ERCP) in four children with choledochal cyst (CC). The first two had mild or chemical pancreatitis; the third had a history of recurrent cholangitis and was diagnosed as chronic pancreatitis. The fourth manifested with severe, acute pancreatitis. All children were found to have an impaired flow through the papilla of Vater. In the first three cases, the duct of Santorini (DS) seemed to play an important role in the pancreatic drainage. In the fourth case, however, the duct was found to be absent. ERCP findings in additional eleven children without CC also were reviewed, and in this group the DS did not seem to play any significant role in pancreatic drainage. These results indicate that in children with common bile duct (CBD) anomalies, the DS may relieve the obstruction and ameliorate the pancreatitis.

Acute Disease↗
PubMed1991

Oral neurotensin increases gastrointestinal transit in suckling rats.

Several neuropeptides known to alter gastrointestinal motility are present in milk. We investigated the effect of gastric administration of neurotensin, bombesin, somatostatin, and vasoactive intestinal polypeptide on gastrointestinal motility in suckling rats. We gavage fed 7- to 10-day-old rats with a meal consisting of 10 microliters/g of body weight of 0.9% NaCl with 51Cr tracer and one of the peptides (0, 0.1, 10, and 1,000 ng/ml). We estimated the rates of gastric emptying and the small intestinal transit from the distribution of the radioactivity in the gut. Approximately one-half of the counts emptied from the stomach in 15 min. Both gastric emptying and small intestinal transit were time dependent and were accelerated by metoclopramide and inhibited by butylscopolamine. Neurotensin 1 micrograms/ml accelerated the gastric emptying by 35% (p less than 0.02). Small intestinal transit was also accelerated (p less than 0.05). The other neuropeptides had no effect on gastric emptying and small intestinal transit. Neurotensin did not change either the gastric emptying or small intestinal transit in weaned rats, 40-50 days old, studied in the same manner. These data suggest that the intraluminal administration of neurotensin may increase gastrointestinal motility in suckling animals.

Administration, Oral↗
PubMed1990

Recurrent pneumonia caused by diffuse oesophageal spasm.

A 14-month-old severely retarded girl with a history of regurgitation, aspiration, and recurrent pneumonia was found to suffer from diffuse oesophageal spasm. This diagnosis was made by oesophageal cineradiography. This case suggests that diffuse oesophageal spasm is an oesophageal motility disorder that causes respiratory disease in the retarded child.

Esophageal Spasm, Diffuse↗