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Biomedical subjects

Nobuhide Oshitani

Publications and source records attributed to Nobuhide Oshitani.

At least 37 records · Page 2Linked to original sources
PubMed2005

Relationship between peroxisome proliferator-activated receptor-gamma expression and differentiation of human esophageal squamous cell carcinoma.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, is involved in suppressing the growth of several tumors. We showed that PPAR-gamma is expressed in Barrett's adenocarcinoma cell lines and inhibited the growth of these lines through the induction of G1 cell cycle arrest and apoptosis. We examined PPAR-gamma expression in human esophageal squamous cell carcinoma (SCC) in vitro and in vivo and investigated whether PPAR-gamma ligands affect the proliferation and apoptosis of human SCC cell lines. Biopsy specimens (n=46) obtained from human SCC of the esophagus were stained using a monoclonal antibody against human PPAR-gamma. We assessed the effects of PPAR-gamma ligands on the growth of SCC cells by adding 15-deoxy prostaglandin J2 (15d-PGJ2), or troglitazone to six human esophageal SCC cell lines (TE-1, TE-2, TE-3, TE-5, TE-8, and TE-9). Immunohistochemical staining showed that 34 of 46 (73.9%) SCC of the esophagus expressed PPAR-gamma. All SCC cell lines expressed PPAR-gamma mRNA and protein, especially when poorly differentiated (TE-2, TE-5, and TE-9). The PPAR-gamma ligands significantly and dose-dependently inhibited the proliferation of SCC lines, except for well-differentiated TE-1 and TE-3. Apoptosis was induced by 15d-PGJ2 (10 microM) in all tested SCC lines except TE-1, whereas troglitazone (50 microM) was marginally effective in only the TE-2 and TE-3 cell lines. The present findings suggest that PPAR-gamma could be a therapeutic target for treating squamous cell carcinoma of the esophagus, possibly through the induction of apoptosis.

Antibodies, Monoclonal↗
PubMed2005

[Extraintestinal complications in patients with ulcerative colitis].

Extraintestinal complications of patients with ulcerative colitis contribute to quality of life and mortality of the patients. Extraintestinal complications involve many organ systems. Skin, mucocutaneous, hepatobiliary, and joints complications are major extraintestinal complications. Some disorders correspond the activity of the colitis, other complications develop independently of the bowel inflammation. The purpose of this review is to update the clinicians concerning the etiology, clinical course and the therapy of the extraintestinal manifestations associated with ulcerative colitis.

Cholangitis, Sclerosing↗
PubMed2004

Increased expression of transforming growth factor-alpha and epidermal growth factor receptors in rat chronic reflux esophagitis.

BACKGROUND AND AIM: Transforming growth factor-alpha (TGF-alpha), which binds to epidermal growth factor receptors (EGF-R), stimulates esophageal epithelial cell proliferation, enabling rapid repair after mucosal injury. The aim of the present study was to examine epithelial proliferation and dynamics of TGF-alpha and EGF-R gene and protein expression in rat chronic acid reflux esophagitis. METHODS: Gastric acid reflux esophagitis was induced in Wistar rats by ligating the transitional region between the forestomach and the glandular portion, and by covering the duodenum near the pyloric ring with a small piece of an 18Fr Nélaton catheter. Epithelial cell proliferation was assessed by bromodeoxyuridine (BrdU) uptake. Expression of TGF-alpha and EGF-R mRNA and protein was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. RESULTS: Esophageal lesions were observed in the lower and middle esophagus. Histologically, a significant increase in mucosal thickening with elongation of lamina propria papillae and basal cell hyperplasia was observed. The BrdU labeling index was significantly increased from 2.7 +/- 1.0 in normal mucosa and 2.8 +/- 1.2 in background mucosa adjacent to the esophageal lesion, to 60.3 +/- 32.7 in the lesions of chronic esophagitis. Expression of TGF-alpha and EGF-R mRNA in the esophageal lesion significantly increased compared to those in the control and background tissue, whereas treatment with rabeprazole significantly inhibited increases in TGF-alpha and EGF-R mRNA expression. According to immunohistochemical study, TGF-alpha and EGF-R revealed strong expression in esophageal lesions compared with control and background mucosa. The superficial layer of the esophagus was strongly positive for TGF-alpha and most cells in regions of basal hyperplasia had a positive reaction for EGF-R in the esophagitis lesion. CONCLUSION: Epithelial proliferation and expression of TGF-alpha and EGF-R were significantly increased in rat chronic reflux esophagitis. Activation of TGF-alpha and EGF-R genes in response to acid reflux may facilitate rapid mucosal healing by stimulating epithelial proliferation. These results suggest that TGF-alpha and EGF-R play crucial roles in rat chronic reflux esophagitis.

Amino Acid Sequence↗
PubMed2004

Safety and efficacy of S-1, a novel oral fluorouracil antitumor drug, for a chronic renal failure patient maintained on hemodialysis.

OBJECTIVE: S-1 is a novel oral fluorouracil antitumor drug that combines three pharmacological agents: tegafur (FT), a prodrug of 5-fluorouracil (5-FU); 5-chloro-2,4-dihydroxypyridine (CDHP), an inhibitor of dihydropyrimidine dehydrogenase, and potassium oxonate (Oxo), a reducer of gastrointestinal toxicity. S-1 has safe and potent antitumor effects in patients with gastric cancer via these respective functions. However, the plasma 5-FU concentration is suspected to accumulate in patients with renal dysfunction, because 50% of the CDHP is excreted into the urine. There are no useful data on safety and efficacy of S-1 in chronic renal failure patients maintained on hemodialysis (HD). We examined the influence of HD on the pharmacokinetics (PK) of S-1 and its therapeutic efficacy in liver metastases from gastric cancer. METHODS: For the HD patient, the dose of S-1 in a single-administration study was set at 50 mg/body/day (41.7% of the recommended dose of 80 mg/m2/day). S-1 was given to the patient 24 h after HD. Blood samples were obtained before administration and 2, 4, 6, 8, and 24 h thereafter and 1, 2, 4, and 72 h after the following HD session. The PK parameters (5-FU, CDHP, Oxo, and FT) were measured, and Cmax, Tmax, AUC0-24, and T1/2 were calculated. The dose of consecutive or maintained administrations was determined. RESULTS: Both an increase in Cmax and an elongation of T1/2 for 5-FU, CDHP, and Oxo, but not for FT, occurred in this case as compared with controls. The AUC0-24 of 5-FU in this case was similar to that of controls at the standard dose. After HD, 87.8, 54.5, 77.4, and 66.2% of 5-FU, CDHP, Oxo, and FT, respectively, were eliminated. A slight accumulation of CDHP did not alter the 5-FU PK. Consecutive or maintained S-1 oral administration at the same dose showed similar effects on all PK parameters of a single-administration test. Liver metastases almost totally regressed with no adverse events 4 weeks after S-1 treatment (50 mg/body/day three times a week). CONCLUSION: Adjusted doses of S-1 according to the results of PK studies may provide therapeutic safety and high efficacy in liver metastases from gastric cancer, even in chronic renal failure patients maintained on HD.

Administration, Oral↗
PubMed2004

Activation of human neutrophils by granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, and tumor necrosis factor alpha: role of phosphatidylinositol 3-kinase.

Stimulation of human neutrophils with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage CSF (GM-CSF), or tumor necrosis factor alpha (TNF) resulted in phosphorylation of Akt, the potency being GM-CSF > G-CSF = TNF, which was inhibited by wortmannin. The findings indicated that phosphatidylinositol 3-kinase (PI3K) is activated by these cytokines. The possible participation of PI3K in activation of neutrophil functions induced by these cytokines was explored with PI3K inhibitors (wortmannin and LY294002). Superoxide release and adherence induced by GM-CSF or TNF were inhibited by PI3K inhibitors. Actin reorganization and morphological changes induced by G-CSF or GM-CSF were also inhibited by wortmannin, whereas these responses induced by TNF were unaffected by wortmannin. These findings suggested that PI3K is differentially involved in cytokine-mediated activation of neutrophil functions depending on the cytokines used. The results also showed that activation of extracellular signal-regulated kinase, but not p38 mitogen-activated protein kinase, induced by these cytokines is partly mediated by PI3K activation.

Androstadienes↗
PubMed2004

Has Helicobacter pylori eradication for peptic ulcer been overrated?

Discovery of Helicobacter pylori has changed the life cycle of peptic ulcer disease (PUD). However, PUD does not completely disappear after elimination of H. pylori. Some ulcers recur even after successful eradication of H. pylori in non-users of non-steroidal anti-inflammatory drug (NSAID). In addition, the incidence of H. pylori-negative, non-NSAID PUD (idiopathic PUD) is reported to increase with time. Moreover, H. pylori-positive ulcers are not always H. pylori-induced ulcers because there are two paradoxes of the H. pylori myth: the existence of H. pylori-positive non-recurring ulcer and recurring ulcer after cure of H. pylori infection. Taken together, H. pylori is not the only cause of peptic ulcer disease. Therefore, it is still necessary to seriously consider the pathophysiology and the management of the ulcers, which may exist after elimination of H. pylori.

Causality↗
PubMed2004

[Pathogenesis and treatment of refractory gastroesophageal reflux disease in Japanese patients].

Prevalence of refractory gastroesophageal reflux disease (GERD) defined as a patient who have persistent GERD symptoms during treatment with proton pump inhibitor (PPI) is rare in Japanese patinets. Pathogenesis of refractory GERD is associated with several factors including dysfunction of esophageal motility, presence of severe hiatal hernia, complication such as stricture and short esophagus, extensive metabolizer of CYP2C19 genotype, nocturnal gastric acid breakthrough, absence of H. pylori infection, or bile reflux. Examination by 24 hr pH monitoring is necessary to assess refractory GERD and if acid suppression is insufficient, treatment with double doses of PPIs or combination of PPI and H2 blocker is effective. However, most cases of refractory GERD are required surgical treatment. Endoscopic therapy might be useful for refractory GERD in future.

Aryl Hydrocarbon Hydroxylases↗
PubMed2003

Increased expression of cytokines and adhesion molecules in rat chronic esophagitis.

BACKGROUND/AIMS: Cytokines and adhesion molecules regulate many inflammatory processes in several gastrointestinal diseases. The dynamics of cytokines and adhesion molecules in reflux esophagitis are unknown in detail. We examined the expression and dynamics of interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-2, GRO/cytokine-induced neutrophil chemoattractant-2alpha (CINC-2alpha), intercellular adhesion molecule-1 (ICAM-1), leukocyte function-associated antigen 1 (LFA-1; CD11a/CD18), and Mac-1 (CD11b/CD18) in rat chronic reflux esophagitis. METHODS: Chronic acid reflux esophagitis was induced in Wistar rats by ligating the transitional region between the forestomach and the glandular portion and wrapping the duodenum near the pylorus with a small piece of an 18-Fr Nélaton catheter. Rats were killed 3 or 21 days after operation. The levels of mRNA expression of cytokines and ICAM-1 were determined by real-time quantitative RT-PCR. Localization of adhesion molecules and cytokines was investigated by immunohistochemical staining, and numbers of LFA-1- or Mac-1-positive cells were quantified. RESULTS: IL-1beta, TNF-alpha, MCP-1, MIP-1alpha, MIP-2, CINC-2alpha, and ICAM-1 mRNA expression was significantly increased in esophageal lesions compared with normal esophagus. There were few these cytokines- or adhesion molecule-positive cells in normal esophagus. In regions of esophagitis, numerous inflammatory leukocytes in lamina propria and the submucosal layer exhibited positive reactions for these cytokines and endothelial cells were intensely stained for ICAM-1. Numbers of LFA-1- and Mac-1-positive cells were significantly increased in rat chronic esophagitis. Treatment with rabeprazole almost completely inhibited development of chronic acid reflux esophagitis and significantly decreased expression of cytokines and ICAM-1 mRNA in esophageal tissue compared with control. CONCLUSION: Cytokines and adhesion molecules play important roles in the pathogenesis of chronic reflux esophagitis in this rat model.

Animals↗
PubMed2003

Anti-inflammatory effect of two isoforms of COX in H. pylori-induced gastritis in mice: possible involvement of PGE2.

Neutrophil infiltration mediated by TNF-alpha is associated with various types of gastric injury, whereas PGs play a crucial role in gastric defense. We examined roles of two isoforms of cyclooxygenase (COX) and PGE2 in Helicobacter pylori-induced gastritis in mice. Mice infected with H. pylori were given selective COX-1 inhibitor SC-560 (10 mg/kg), selective COX-2 inhibitor NS-398 (10 mg/kg), or nonselective COX inhibitor indomethacin (2 mg/kg) with or without 16,16-dimethyl PGE2 for 1 wk. H. pylori infection increased levels of mRNA for COX-1 and -2 in gastric tissue by 1.2-fold and 3.3-fold, respectively, accompanied by a significant increase in PGE2 production by gastric tissue. H. pylori infection significantly elevated MPO activity, a marker of neutrophil infiltration, and epithelial cell apoptosis in the stomach. SC-560 augmented MPO activity and epithelial cell apoptosis with associated reduction in PGE2 production, whereas NS-398 had the same effects without affecting PGE2 production. Inhibition of both COX-1 and -2 by indomethacin or concurrent treatment with SC-560 and NS-398 resulted in a stronger increase in MPO activity and apoptosis than inhibition of either COX-1 or -2 alone. H. pylori infection elevated TNF-alpha mRNA expression in the stomach, which was further increased by indomethacin. Effects of COX inhibitors on neutrophil infiltration, apoptosis, and TNF-alpha expression in H. pylori-infected mice were abolished by exogenous 16,16-dimethyl PGE2. In conclusion, PGE2 derived from either COX-1 or -2 is involved in regulation of gastric mucosal inflammation and contributes to maintenance of mucosal integrity during H. pylori infection via inhibition of TNF-alpha expression.

Animals↗
PubMed2003

Cross-reactivity of yeast antigens in human colon and peripheral leukocytes.

Elevation of the serum anti-Saccharomyces cerevisiae antibody (ASCA) level has been reported in patients with Crohn's disease. This study investigated the antigenic distribution of S. cerevisiae in human colon and peripheral leukocytes. ASCA was isolated from sera from patients with Crohn's disease using immuno-affinity chromatography and then biotinylated and assayed immunohistologically and immunocytologically to determine the distribution of antigens recognized by ASCA in human colon and peripheral leukocytes. Immunoblot analysis of yeast extract and human peripheral leukocytes was performed. Immunohistological study using biotinylated ASCA revealed the presence of yeast-like particles in the granulation tissue of inflamed colonic mucosa. Biotinylated ASCA also stained lymphocytes and polymorphonuclear cells infiltrating inflamed intestine. Monocytes in epithelioid granulomas of colon with Crohn's disease were also stained. Polymorphonuclear leukocytes in peripheral blood were also stained with biotinylated ASCA. The antigens reactive to ASCA among heat-extracted, non-heat-extracted yeast antigens, and human leukocyte extract differed. The findings of cross-reactivity of polymorphonuclear leukocytes with S. cerevisiae antigen and the presence of S. cerevisiae antigen in Crohn's disease granulomas suggest the possibility of involvement of S. cerevisiae in the pathogenesis of Crohn's disease.

Adult↗
PubMed2003

Association between gastroesophageal flap valve, reflux esophagitis, Barrett's epithelium, and atrophic gastritis assessed by endoscopy in Japanese patients.

BACKGROUND: Endoscopic grading of the gastroesophageal flap valve (GEFV) is a useful predictor of gastroesophageal reflux status; abnormal GEFV was associated with reflux esophagitis. Atrophic gastritis is often found in Japanese patients and is inversely related to reflux esophagitis. The aim of this study was to examine the association between GEFV, reflux esophagitis, Barrett's epithelium, and atrophic gastritis in Japanese patients by prospective endoscopic assessment. METHODS: We enrolled 548 Japanese patients (296 men and 252 women; mean age, 57.3 years). GEFV was assessed by the classification of Hill and colleagues, reflux esophagitis was assessed by the Los Angeles classification, and the degree of atrophic gastritis was scored as: none, mild, moderate, or severe. Barrett's epithelium was recognized by the endoscopic detection of an upward shift in the columnar lining. RESULTS: Reflux esophagitis and Barrett's epithelium were found in 42 (7.7%) and 67 (12.2%) patients, respectively. An increased prevalence of reflux esophagitis and Barrett's epithelium was correlated with an increased grade of GEFV. Abnormal GEFV (grades III and IV) was a risk for reflux esophagitis (adjusted odds ratio [OR]), 13.33 (95% confidence interval [CI], 6.08-29.25) and Barrett's epithelium (OR, 3.55 [95% CI, 2.04-6.20]), while the presence of atrophic gastritis was inversely associated with reflux esophagitis (OR, 0.15 [95% CI, 0.07-0.36]), but it was not associated with the prevalence of Barrett's epithelium (OR, 1.16 [95% CI, 0.67-2.01]). The prevalence of Barrett's epithelium and the severity of atrophic gastritis increased with age, while that of reflux esophagitis and abnormal GEFV did not change. CONCLUSIONS: Reflux esophagitis and Barrett's epithelium are associated with abnormal GEFV in Japanese patients. The presence of atrophic gastritis is inversely related to reflux esophagitis, but it is not related to Barrett's epithelium in Japanese patients.

Age Factors↗
PubMed2003

Crohn's disease complicated by adult-onset Still's disease.

A 31-year-old man with Crohn's disease developed arthritis, spiking fever, and skin rash indistinguishable from that of adult-onset Still's disease. He was admitted to our hospital because of a periumbilical intestinal skin fistula. Crohn's disease had been diagnosed in 1991, and had required intestinal resection twice, and schizophrenia had been diagnosed in 1993. He developed polyarthritis and spiking fever, accompanied by a macular skin rash on both forearms. Marked hepatosplenomegaly and bilateral pleural effusion were detected on computed tomography examination. These findings are indistinguishable from those of adult-onset Still's disease. Because his mental status had deteriorated following high-dose prednisolone on a previous admission, he was treated with an immunosuppressive agent on this occasion, with the treatment being successful. This is the first report of adult-onset Still's disease complicating Crohn's disease. In patients with Crohn's disease, polyarthritis and skin rash can easily be misdiagnosed as enteropathic arthritis with erythema nodosum associated with the Crohn's disease. Although adult-onset Still's disease may not be fatal, early diagnosis is important because it can, in rare cases, result in life-threatening complications.

Adult↗
PubMed2003

No additive effect between Helicobacter pylori infection and portal hypertensive gastropathy on inducible nitric oxide synthase expression in gastric mucosa of cirrhotic patients.

Increased expression of inducible nitric oxide synthase (iNOS) has been reported in gastric mucosa of patients with Helicobacter pylori infection or portal hypertensive gastropathy (PHG) but whether there is an additive or synergistic impact between H. pylori and PHG on iNOS expression was unknown. Sixty cirrhotic patients and 21 age-matched control subjects without liver disease were included. Biopsies from the gastric antrum and body were obtained for quantitative histological assessment and immunohistochemical staining for iNOS. iNOS staining was detected in endothelial cells and macrophages. In the absence of PHG, H. pylori significantly induced iNOS expression in cirrhotic patients. PHG also significantly induced iNOS expression in H. pylori-negative patients. However, there was no synergistic or additive effect between H. pylori and PHG on this expression. Furthermore, expression of iNOS was significantly higher in patients with severe PHG than in those with mild PHG and without PHG.

Case-Control Studies↗
PubMed2003

Outpatient treatment of moderately severe active ulcerative colitis with pulsed steroid therapy and conventional steroid therapy.

Pulsed steroid therapy may induce rapid remission in patients with moderately severe ulcerative colitis in outpatient clinics. A total of 19 patients with moderately severe active ulcerative colitis who refused hospitalization were treated between October 1999 and September 2001 in the outpatient clinic. Patients were treated with either conventional oral steroid therapy or intravenous pulsed steroid therapy followed by conventional oral steroid therapy. Eight patients received conventional steroid therapy and 11 patients received pulsed steroid therapy followed by conventional steroid therapy. The efficacies of the two types of steroid therapy were equal, but patients with active colitis responded more quickly to pulsed steroid therapy than to conventional steroid therapy. No serious adverse effects were observed. Moderately severe colitis can be safely treated with either conventional or pulsed steroid therapy in the outpatient clinic, but pulsed steroid therapy may induce clinical remission more quickly than conventional steroid therapy.

Administration, Oral↗
PubMed2003

Esophagogastric varices due to arterioportal shunt in a serous cystadenoma of the pancreas in von Hippel-Lindau disease.

Von Hippel-Lindau (VHL) disease is an autosomal dominant inherited disorder characterized by extensively vascularized tumors and cysts in specific organs. Angiogenesis is a striking future of VHL disease with its characteristic cysts and well-vascularized tumors. The hypervascular nature of VHL lesions has been linked to the overproduciton of vascular endothelial growth factor (VEGF) through increased expression of hypoxia inducible factor-1alpha (HIF-1alpha). Here we describe a rare case of VHL disease with esophageal and gastric varices due to arterioportal shunt in a serous cystadenoma of the pancreas, which, upon immunohistochemical examination, exhibited HIF-1alpha and VEGF expression. Rupture of esophageal varices was successfully treated with endoscopic injection sclerotherapy.

Angiography↗