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Biomedical subjects

J C Rhee

Publications and source records attributed to J C Rhee.

48 records · Page 3Linked to original sources

Hypersensitivity to acid in ulcer-like functional dyspepsia.

OBJECTIVES: The mechanism of pain sensation in patients with ulcer-like functional dyspepsia is unclear and there are no guidelines for its treatment. Whilst much research and many pharmacological treatments have provided symptomatic relief of ulcer-like functional dyspepsia through control of acid secretion, the role of acid in ulcer-like functional dyspepsia is unknown. We carried out this study to investigate the role of hypersensitivity to acid in the sensation of pain in ulcer-like functional dyspepsia by direct administration of acid into stomach. METHODS: Twelve patients with ulcer-like functional dyspepsia (5 male, 7 female, mean age 41.0 years old, 7 with mild chronic superficial gastritis, 2 with metaplastic gastritis and 3 with normal endoscopic findings) and seven healthy control subjects (3 male, 4 female, mean age 36.0 years old, 7 with normal endoscopic findings) participated in the study. After overnight fasting, a nasogastric sump tube was inserted and its tip was positioned in the antrum under fluoroscopic guidance. Normal saline or 0.1N hydrochloric acid was administered in random and single blind cross over fashion. The test was considered positive only if similar pain developed-similar to that experienced by the patient under nonstudy condition- during the administration. RESULTS: Five patients (41.7%) developed pain with 0.1N hydrochloric acid administration, but none with normal saline (p < 0.05). None of the healthy controls developed pain upon administration of 0.1N hydrochloric acid or normal saline. CONCLUSION: We suggest that acid hypersensitivity plays a role in the sensation of pain in ulcer-like functional dyspepsia.

Adult↗

Primary T-cell lymphoma of the colon.

A 40-year-old woman had been diagnosed with Crohns disease in September 1994, but later examinations revealed a primary T-cell lymphoma of the colon. Colonoscopic and histological examination showed ulcerative lesions simulating Crohns disease involving the entire colon and the terminal ileum, and she was first diagnosed as having Crohns disease. Differential therapeutic strategies, including corticosteroid, had improved the symptoms which were dominated by abdominal pain. When she visited our institute in April 1995, she presented with bloody stool twice a day, 7 kg weight loss in a period of six months and a slightly painful abdomen. Colonoscopic finding showed geographic ulceration on the entire colon, especially rectum and terminal ileum. The histologic examination of specimens from colonoscopic biopsy showed primary peripheral T-cell lymphoma of the colon. Any dense lymphocyte infiltrates seen in the biopsy specimens obtained from lesions simulating ulcerative colitis or Crohns disease should be assessed to exclude intestinal lymphoma.

Adult↗

Effect of stretch on calcium channel currents recorded from the antral circular myocytes of guinea-pig stomach.

The effect of membrane stretch on voltage-activated Ba2+ current (IBa) was studied in antral circular myocytes of guinea-pig using the whole- cell patch-clamp technique. The changes in cell volume were elicited by superfusing the myocytes with anisosmotic solutions. Hyposmotic superfusate (202 mosmol/l) induced cell swelling and increased peak values of IBa at 0 mV (from -406.6 +/- 45.5 pA to -547.5 +/- 65.6 pA, mean +/- SEM, n = 8) and hyperosmotic superfusate (350 mosmol/l) induced cell shrinkage and decreased peak values of IBa at 0 mV (to -269.5 +/- 39.1 pA, n = 8). Such changes were reversible and the extent of change was dependent on the osmolarity of superfusate. The values of normalized IBa at 0 mV were 1.43 +/- 0.04, 1.30 +/- 0.06, 1.23 +/- 0.04, 1.19 +/- 0.04, 1 and 0. 68 +/- 0.06 at 202, 220, 245, 267, 290 and 350 mosmol/l, respectively (n = 8). IBa was almost completely blocked by nicardipine (5 microM) under hyposmotic conditions. The values of steady-state half-inactivation voltage (-37.7 +/- 3.3 and -36.5 +/- 2.6 mV, under control and hyposmotic conditions, respectively) or the half-activation voltage (-13.6 +/- 2.3 and -13.9 +/- 1.9 mV) of IBa were not significantly changed (P > 0.05, n = 6). Cell membrane capacitance was slightly increased from 50.00 +/- 2.86 pF to 50.22 +/- 2.82 pF by a hyposmotic superfusate (P < 0.05, n = 6). It is suggested that cell swelling increases voltage-operated L-type calcium channel current and that such a property is related to the response of gastric smooth muscle to mechanical stimuli.

Animals↗

Intracellular Ca2+ oscillations in vascular smooth muscle cells.

We monitored caffeine- and histamine-induced [Ca2+]i oscillations by patch-clamp whole-cell recordings of K(Ca)-current in single smooth muscle cells of rabbit cerebral (basilar) artery. Superfusion of caffeine (1 mM) or histamine (1-3 microM) induced periodic oscillations of large whole-cell K-current with fairly uniform amplitudes and intervals. Repetitive activations of the large-conductance K(Ca)-channels were recorded in the cell-attached patch mode. Inclusion of heparin (3 mg/ml) in the pipette solution failed to inhibit the oscillations caused by caffeine treatment, but blocked histamine-evoked oscillations. Ryanodine (1-10 microM) abolished both caffeine- and histamine-induced oscillations. Removal of extracellular Ca2+, but not verapamil or Cd2+, abolished the caffeine-induced oscillations, and the changes in the oscillatory frequency closely reflected the altered Ca2+ influx rate. These results indicate that in smooth muscle cells of the rabbit cerebral artery, ryanodine-sensitive Ca(2+)-induced Ca2+ release (CICR) pools play key roles for the generation of the [Ca2+]i oscillations.

Animals↗

Biliary proteins in patients with and without gallstones.

BACKGROUND: Nucleation from supersaturated bile of calcium salts of cholesterol and bilirubinate is essential in the formation of gallstone. Nucleation requires gallbladder mucin and its main component, glycoprotein, may contribute to gallstone formation by providing a nidus or matrix for precipitation of lipid components. However, biliary protein patterns of patients with gallstones have not been completely explored. METHODS: We have tried to extract, isolate and characterize the proteins in patients with gallstones and without gallstones. 21 bile samples were obtained from patients with different types of gallstones and with no stones at cholecystectomy. Biliary protein concentrations were measured by Lowry and Bensadoun methods, and individual glycoproteins from each of the patients were compared by silver staining and densimetric quantification of Sodium Dodesyl Sulfate Polyacrylamide Gel Electrophoresis. RESULTS: 1) Among 16 gallstones, 5 were cholesterol stones, 5 were calcium bilirubinate stones, and 6 were black pigment stones. 2) The mean protein concentration was highest in bile with cholesterol stones (47.6 mg/ml), 24.2 mg% in bile without gallstones, and 15.9 mg/ml in brown pigment stones. 3) Cholesterol gallstones were found to have 14.2 KD glycoproteins, whereas pigment stones were found to have 66 KD glycoproteins. CONCLUSIONS: Gallbladder proteins from both cholesterol and pigment stones play an important role in the nucleation and growth of calcium salt crystals.

Bile↗

The causes and management of lower GI bleeding: a study based on clinical observations at Hanyang University Hospital.

During the period of the study, lower GI bleeding patients comprised a constant 1.6% of the total admitted patients at Hanyang University Hospital annually. There were no statistically significant changes according to year. The 970 cases were classified as follows: hemorrhoid and anal fissure 65.5%, malignant neoplasm 21.1% (rectal cancer 16.9%, sigmoid colon cancer 3.3%, anal cancer 0.9%), benign neoplasm 4.2%, ulcerative colitis 3.3%, infectious colitis 2.3%, ischemic colitis 1.8%, radiation colitis 1.3%, diverticulosis 0.3%, and others 0.2%. Ulcerative colitis and rectosigmoid cancer showed increasing trends, while other disease groups showed no change in the occurrence rate. Hemorrhoid and anal fissure developed mostly in the 30s age group, benign polyp and ulcerative colitis in the 40s age group, malignant neoplasm in the 50s age group, and ischemic colitis and radiation colitis in the 60s age group. There was no sexual predominance of lower GI bleeding. About 10% of the patients admitted to the hospital needed transfusions, particularly patients with ulcerative colitis (21.9%) and radiation colitis (23.1%). 20.2% of the patients improved with supportive measures and medical treatment and 79.8% underwent surgical operation. In particular, 51.2% of the patients with benign neoplasm underwent polypectomies.

Adolescent↗

Mechanism of oleic acid-induced inhibition on gastric acid secretion in rats.

We investigated the existence of an enterogastrone in rats induced by duodenal administration of oleic acid. Acid secretion by the luminally perfused stomach was stimulated in anesthetized rats by intravenous infusion of 0.3 micrograms.kg-1.h-1 pentagastrin. Intraduodenal administration of 3 mmol of oleic acid produced a profound inhibition (94%) of pentagastrin-stimulated acid output in 10 rats (P less than 0.01). Of several peptides in plasma including secretin, neurotensin, somatostatin, and peptide YY, only secretin was found to increase significantly (P less than 0.001). A similar degree of inhibition of acid output (93%) was caused by porcine secretin, 5.6 pmol.kg-1.h-1, given intravenously to mimic the plasma level of secretin produced by oleic acid infusion. The inhibitory effect of oleic acid on the acid secretion was completely reversed by intravenous injection of a rabbit antisecretin serum but not by a normal rabbit serum. These observations strongly suggest that the inhibition was mediated via circulating secretin. The inhibition produced by either oleic acid or secretin was completely blocked by indomethacin. The blocking action was completely reversed by intravenous administration of 48 micrograms.kg-1.h-1 prostaglandin E2. We conclude that endogenous secretin is a major enterogastrone released by oleic acid in anesthetized rats and that the inhibitory action of secretin requires endogenous prostaglandins.

Animals↗

Ulcerogenic tumor syndrome of the pancreas associated with a nongastrin acid secretagogue.

Among 30 patients with islet cell neoplasms or hyperplasia who exhibited marked gastric acid hypersecretion and peptic ulceration and/or diarrhea, fasting plasma gastrin concentrations were less than 150 pg/ml in 11 patients, whereas the remaining 19 patients had hypergastrinemia. Plasma extracts from seven of these 11 patients were assayed for acid secretagogue activity in rats. All seven plasma extracts had secretagogue activity that was not found in the plasma extracts of ten patients with ordinary duodenal ulcer disease. Each of the tumor or pancreatic tissue extracts obtained from nine patients exhibited secretagogue activity in rats even though tissue gastrin content was 101.9 pmol (213.8 ng).g-1 or less. The secretagogue activity of the tumor extracts was confirmed in conscious gastric fistula dogs. The tumors' secretagogue activity, in contrast to gastrin, was destroyed by trypsin. It was eluted between porcine motilin and human gastrin I from a Sephadex G-50 (Pharmacia LKB Biotechnology, Inc., Piscataway, NJ) superfine column and was not retained by CM-cellulose, at pH 8.5. Its retention time during reverse phase HPLC on a C18 column also differed from those of G17 and G34. Thus, this secretagogue activity appeared mediated by a small, acidic peptide with a molecular size of about 2000 to 3000 daltons. The present study indicates that plasma and tumor extracts of these 11 patients contain a gastric acid secretagogue activity mediated by a nongastrin peptide. We suggest that what may be a distinct clinical entity associated with endocrine neoplasms of the pancreas should be considered in the face of excessive acid hypersecretion without fasting hypergastrinemia.

Adult↗

Role of autonomic dysfunction in patients with functional dyspepsia.

BACKGROUND: The role of autonomic dysfunction in patients with functional dyspepsia is not completely understood. AIMS: 1. to prospectively assess abnormalities of autonomic function in patients with functional dyspepsia, 2. to assess whether autonomic dysfunction in these patients is associated with a. visceral hypersensitivity or b. delayed gastric emptying or c. severity of dyspeptic symptoms. PATIENTS: A series of 28 patients with functional dyspepsia and 14 healthy volunteers without gastrointestinal symptoms were studied. METHODS: All patients and controls were submitted to a battery of five standard cardiovascular autonomic reflex tests, dyspeptic questionnaire, gastric barostat tests and gastric emptying tests. RESULTS: 1. Autonomic function tests showed that both sympathetic and parasympathetic scores of dyspeptic patients were significantly higher than in controls; 2. visceral hypersensitivity was confirmed in dyspeptics in response to proximal gastric distension, demonstrating lower pain threshold; 3. delayed gastric emptying occurred more frequently in patients with functional dyspepsia than in controls; 4. epigastric pain and epigastric burning were significantly more prevalent in patients with definite evidence of autonomic dysfunction; 5. No significant association was found between presence of autonomic dysfunction and presence of visceral hypersensitivity or presence of delayed gastric emptying in patients with functional dyspepsia. CONCLUSIONS: We concluded that a possible role of autonomic dysfunction in eliciting dyspeptic symptoms could not be determined from alterations in visceral hypersensitivity or delayed gastric emptying. Autonomic dysfunction might not be the major explanation for symptoms associated with functional dyspepsia.

Abdominal Pain↗

Interaction between cyclooxygenase-2 and inducible nitric oxide synthase in gastric cancer.

BACKGROUND: Chronic expression of cylcooygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) may play an important role in gastric carcinogenesis. Thus, the purpose of our study was to assess the expression of COX-2 and iNOS messenger RNA (mRNA) in gastric cancer and to investigate the correlation between the expression of COX-2 and iNOS mRNA in these patients. STUDY: Twenty-three gastric carcinoma specimens and accompanying adjacent specimens were obtained from surgical resection. The expression of COX-2 and iNOS were examined by comparative reverse transcription polymerase chain reaction. RESULTS: Cylcooygenase-2 and iNOS mRNA were significantly higher in gastric cancer tissues than in adjacent normal tissues. There was significant correlation between the levels of COX-2 and iNOS mRNA in carcinoma tissues. However, there was no significant correlation between the level of COX-2 or iNOS mRNA expression and several clinicopathologic parameters in these patients. CONCLUSION: The expression of COX-2 and iNOS may be one of the factors that contribute to gastric carcinogenesis.

Adenocarcinoma↗