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Biomedical subjects

Tetsuo Arakawa

Publications and source records attributed to Tetsuo Arakawa.

At least 19 recordsLinked to original sources
PubMed2005

Prevalence of gastroesophageal reflux disease and gastroesophageal reflux disease symptoms in Japan.

BACKGROUND AND AIM: Epidemiological studies have shown that 10-48% of people in developed countries have gastroesophageal reflux disease (GERD) symptoms such as heartburn and acid regurgitation. The present study aimed to examine the prevalence of GERD symptoms and GERD in Japanese subjects. METHODS: A cross-sectional study of Japanese subjects who visited a clinic for a routine health check up was carried out. Subjects were asked to fill out a self-report questionnaire. GERD was defined as the presence of heartburn and/or acid regurgitation at least twice per week. RESULTS: Of the 6035 eligible subjects, 2662 (44.1%) reported having had heartburn and/or acid regurgitation during the past year: 124 (2.1%) daily, 275 (4.6%) twice per week, 773 (12.8%) twice per month and 1490 (24.7%) less than twice per month. Three hundred and ninety-nine (6.6%) subjects were diagnosed as having GERD and there was no relationship between the prevalence of GERD and either sex or age. The prevalence of bothersome GERD symptoms was significantly higher in subjects with GERD than in those without GERD. CONCLUSION: Approximately 6.6% of Japanese have GERD and most persons with GERD described heartburn or acid regurgitation as bothersome.

Adult↗
PubMed2005

Dislocation of tight junction proteins without F-actin disruption in inactive Crohn's disease.

Crohn's disease is associated with increased permeability of the intestinal barrier even in quiescent patients. Increased intestinal permeability may cause dysregulated immunological responses in the intestinal mucosa that leads to chronic intestinal inflammation. We have studied the expression of tight junction proteins (occludin and zonula occludens), alpha2-smooth muscle actin, TGF-beta with a cytoskeletal protein (F-actin) in the intestinal epithelium of patients with inflammatory bowel disease. Surgical samples were obtained from 6 controls (individuals without inflammatory bowel disease), 8 patients with ulcerative colitis and 7 patients with Crohn's disease. F-actin was visualized with fluorescein phalloidin. Tight junction proteins, alpha2 smooth muscle actin, and TGFbeta were visualized by the immunofluorescent method. Occludin and zonula occludens found in apical tight junctions in normal epithelium were dislocated to the basolateral position and in the lamina propria extracellular matrix in patients with Crohn's disease, while the structure of F-actin was maintained in inactive or minimally inflamed mucosa. TGF-beta positive inflammatory cells were increased in ulcerative colitis and Crohn's disease mucosa. Subepithelial myofibroblasts were constitutively found in controls, ulcerative colitis, and Crohn's disease mucosa. Latent dislocation of tight junction proteins, without disturbance of the cytoskeleton in the inactive mucosa of patients with Crohn's disease, may permit the invasion of gut antigens because the functional disruption of tight junctions could initiate an altered immune response.

Actins↗
PubMed2005

Significance of increased proliferation of immature plasma cells in the appendix of patients with ulcerative colitis.

The etiology of ulcerative colitis (UC) is not known. Recent studies support a primary role of the appendix in the pathogenesis of UC, however phenotypical studies of proliferating cells in the appendix have not been reported. We report phenotypical studies of lymphocytes and of proliferating subpopulations in the appendix of patients with inflammatory bowel disease and of controls. Surgical samples of the appendix were obtained from 5 patients with colon cancer, 5 with acute appendicitis, 12 with UC and 7 with Crohn's disease (CD). Frozen sections were cut from fixed samples, and immunostained with lymphocyte markers and anti-Ki-67 antibodies. The number of Ki-67(+) proliferating cells, CD19, and CD138 cells was significantly higher in the appendix of patients with UC than in controls, patients with acute appendicitis, and patients with CD. Immunohistological double staining revealed significant proliferation of CD3, CD19, and CD138 cells in the appendix of patients with UC. The proportions of Ki-67(+) cells in CD3, CD19, and CD138 cells were significantly higher in both total UC patients and patients in remission-stage UC, than in controls, patients with acute appendicitis, and patients with CD. Lamina propria cells in the appendix of patients with UC showed augmented proliferation with increased numbers of CD19 and CD138 cells. The number of CD3 cells was not significantly increased, but the proportion of proliferating CD3 cells was increased. An increased proportion of Ki-67(+) cells in CD19 and CD138 cells represents proliferation of immature plasma cells in the appendix of patients with UC, and proliferation of such immature plasma cells was seen in both active- and remission-stage UC. Proliferation of immature plasma cells in the appendix of patients with UC suggests a primary role of humoral immune responses in the pathogenesis of UC.

Adolescent↗
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↗
PubMed2004

Monocyte chemotactic protein-1 regulates leukocyte recruitment during gastric ulcer recurrence induced by tumor necrosis factor-alpha.

TNF-alpha has numerous biological activities, including the induction of chemokine expression, and is involved in many gastric injuries. C-C chemokines [monocyte chemotactic protein (MCP)-1 and macrophage inflammatory protein (MIP)-1alpha] and C-X-C chemokines [MIP-2 and cytokine-induced neutrophil chemoattractant (CINC)-2alpha] mediate chemotaxis of monocytes and neutrophils, respectively. We examined the roles of TNF-alpha and dynamics of chemokine expression in gastric ulceration including ulcer recurrence and indomethacin-induced injury. Rats with healed chronic gastric ulcers received intraperitoneal TNF-alpha to induce ulcer recurrence. Some rats were given neutralizing antibodies against neutrophils or MCP-1 together with TNF-alpha. In a separate experiment, rats were orally administered 20 mg/kg indomethacin with or without pretreatment with pentoxifylline (an inhibitor of TNF-alpha synthesis) or anti-MCP-1 antibody. TNF-alpha (1 microg/kg) induced gastric ulcer recurrence after 48 h, which was completely prevented by anti-neutrophil antibody. TNF-alpha increased the number of macrophages and MCP-1 mRNA expression in scarred mucosa from 4 h, whereas it increased MPO activities (marker of neutrophil infiltration) and mRNA expression of MIP-2 and CINC-2alpha from 24 h. Anti-MCP-1 antibody inhibited leukocyte infiltration with reduction of the levels of C-X-C chemokines and prevented ulcer recurrence. Indomethacin treatment increased TNF-alpha/chemokine mRNA expression from 30 min and induced macroscopic erosions after 4 h. Pentoxifylline inhibited the indomethacin-induced gastric injury with reduction of neutrophil infiltration and expression of chemokine (MCP-1, MIP-2, and CINC-2alpha). Anti-MCP-1 antibody also inhibited the injury and these inflammatory responses but did not affect TNF-alpha mRNA expression. In conclusion, increased MCP-1 triggered by TNF-alpha may play a key role in gastric ulceration by regulating leukocyte recruitment and chemokine expression.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2004

Dieulafoy's vascular malformation of the jejunum: first case report of laparoscopic treatment.

A case of Dieulafoy's vascular malformation of the jejunum treated by laparoscopic surgery is described. The patient was a 31-year-old-woman who had complained of melena and had severe anemia needing blood transfusion. Angiography revealed microaneurysms and hypervascularity of the jejunum in the area between the first and second jejunal arterial fields. Laparoscopic partial resection of the jejunum was performed. The resected specimen was histologically diagnosed as Dieulafoy's vascular malformation. Since the operation, the patient has been free of melena and anemia. Small-intestinal Dieulafoy's vascular malformation is rare, as only 41 cases have been reported during the past three decades. Almost two-thirds of the patients were under 40 years old. Most of the patients complained of melena. The lesion was preoperatively identified in 14 of the 41 patients, while angiography was useful to define the lesion. Thirty-six of 37 patients for whom treatment methods were reported were surgically treated. While there are various treatment methods for intestinal bleeding, a surgical operation is often needed. When the disease location is obvious, treatment with laparoscopic surgery can reliably produce good results, in terms of its rate of cure, minimal invasiveness, and better cosmetic effect.

Adult↗
PubMed2004

Oxidized low-density lipoprotein levels circulating in plasma and deposited in the tissues: comparison between Helicobacter pylori-associated gastritis and acute myocardial infarction.

BACKGROUND: Oxidized low-density lipoprotein (ox-LDL) is a key factor in the progression of atherosclerosis. We developed a sensitive method for measuring plasma ox-LDL levels using a novel anti-ox-LDL antibody. Recently, several studies have shown positive associations between Helicobacter pylori (H pylori) infection and coronary heart disease. Thus the question arises whether an increase in the plasma levels of ox-LDL occurs in patients with H pylori gastritis. METHODS: We measured plasma ox-LDL levels in patients with H pylori gastritis (n = 27) and compared them with those in patients with acute myocardial infarction (AMI) (n = 62) and stable angina pectoris (SAP; n = 63) and those in control subjects (n = 64). In addition, ox-LDL localization and the presence of macrophages and neutrophils were studied immunohistochemically in gastritis specimens and in coronary culprit lesions obtained from patients with AMI. RESULTS: Plasma ox-LDL levels in patients with AMI were significantly higher than those in patients with SAP (P <.0001), patients with H pylori gastritis (P <.0001), or in control subjects (P <.0001; AMI, 1.34 +/- 0.95; SAP, 0.61 +/- 0.29; Gastritis, 0.53 +/- 0.17; control, 0.57 +/- 0.23 ng/5 microg LDL protein). Immunohistochemically, H pylori gastritis specimens showed distinct infiltration of macrophages and myeloperoxidase-positive neutrophils; however, ox-LDL localization was not detected. In contrast, coronary culprit plaques revealed strong positivity for ox-LDL in ruptured lipid cores with abundant macrophage-derived foam cells, and these plaques also contained myeloperoxidase-positive neutrophils. CONCLUSION: Our results suggest that plasma ox-LDL levels do not seem to be associated with H pylori infection, but do relate to coronary plaque instability in AMI.

Antibodies, Bacterial↗
PubMed2004

Herb medicine Inchin-ko-to (TJ-135) regulates PDGF-BB-dependent signaling pathways of hepatic stellate cells in primary culture and attenuates development of liver fibrosis induced by thioacetamide administration in rats.

BACKGROUND/AIMS: We studied the effect of Inchin-ko-to (TJ-135), a herb medicine that has been clinically used for liver cirrhosis in Japan, on liver fibrosis in a rat model and on the function of stellate cells. METHODS: Rat liver fibrosis was generated by thioacetamide (TAA) administration. DNA synthesis was assessed by 5-bromo-2'-deoxyuridine incorporation assay. Protein expression was analysed by western blotting. Collagen and fibronectin mRNA expression were analysed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: TJ-135 improved liver fibrosis induced in rats by TAA administration. TJ-135 reduced collagen deposition and the expression of smooth muscle alpha-actin in fibrotic liver tissues and decreased the serum level of hyaluronic acid. In primary-cultured stellate cells, TJ-135 suppressed DNA synthesis and the expression of collagen alpha 1(I), collagen III, and fibronectin mRNAs. It hampered DNA synthesis and migration of PDGF-BB-stimulated stellate cells through inhibiting phosphorylation of PDGF receptor-beta and down-stream signaling pathways. Among TJ-135 components, 3-methyl-1,6,8-trihydroxyanthraquinone (emodin) derived from Rhei rhizoma was found to be the most active molecule. CONCLUSIONS: TJ-135 and emodin regulate PDGF-dependent events in stellate cells and attenuate the development of liver fibrosis. Their clinical use may be beneficial for the therapy of human liver fibrosis.

Actins↗
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

p16 promoter hypermethylation in human hepatocellular carcinoma with or without hepatitis virus infection.

BACKGROUND: Epigenetic alteration through methylation is one of the most important steps in carcinogenesis. However, the relation between hepatitis virus infection and epigenetic alterations is poorly understood. METHODS: Sixteen patients without hepatitis B virus (HBV) and hepatitis C virus (HCV) and 35 patients with HBV or HCV who underwent liver resection for hepatocellular carcinoma (HCC) were studied. Mutation of p53 was detected by direct sequencing. Methylation status of p16 was evaluated in tumor and noncancerous liver tissues by methylation-specific polymerase chain reaction. RESULTS: In HCC without HBV and HCV, p53 mutations were detected in 5 (31%) of 16 HCCs. Methylation of p16 promoter was detected in 2 (25%) of 8 moderately differentiated HCCs, 6 (75%) of 8 poorly differentiated HCCs, and none of 16 noncancerous tissue specimens. In HCC with HBV or HCV, p53 mutations were detected in 8 (23%) of 35 HCCs. Methylation of p16 promoter was detected in 2 (100%) of 2 well-differentiated HCCs, 13 (76%) of 17 moderately differentiated HCCs, 12 (75%) of 16 poorly differentiated HCCs, and 9 (26%) of 35 noncancerous liver tissue specimens. CONCLUSIONS: Our results suggest that hepatitis viruses might induce methylation of p16 promoter in liver with chronic inflammation, before appearance of HCC.

Carcinoma, Hepatocellular↗
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

TIPS versus transcatheter sclerotherapy for gastric varices.

OBJECTIVE: The purpose of our study was to compare the efficacy and long-term results of transjugular intrahepatic portosystemic shunt (TIPS) with those of transcatheter sclerotherapy for the treatment of gastric varices. MATERIALS AND METHODS: A total of 139 cirrhotic patients with gastric varices underwent endovascular treatment. Of the 139 patients, 104 without hepatocellular carcinoma were enrolled; 27 patients were treated with TIPS, and 77 patients with transcatheter sclerotherapy. Bleeding of gastric varices and survival rates were compared between the TIPS and transcatheter sclerotherapy groups. Multivariate analysis was used to identify the prognostic factors for gastric variceal bleeding and survival. Changes in liver function were evaluated in each group. RESULTS: The cumulative gastric variceal bleeding rate at 1 year was 20% in the TIPS group and 2% in the transcatheter sclerotherapy group (p < 0.01). The prognostic factor associated with gastric variceal bleeding was the treatment method. The cumulative survival rates at 1, 3, and 5 years were, respectively, 81%, 64%, and 40% in the TIPS group and 96%, 83%, and 76% in the transcatheter sclerotherapy group (p < 0.01). The prognostic factors for survival were the treatment method and the Child-Pugh classification of liver disease. For patients categorized in Child-Pugh class A, the survival rate was higher in the transcatheter sclerotherapy group than in the TIPS group (p < 0.01). For patients in Child-Pugh classes B and C, no significant difference was seen between the two groups. Liver function tended to improve in the transcatheter sclerotherapy group. CONCLUSION: Transcatheter sclerotherapy may provide better control of gastric variceal bleeding than TIPS. Transcatheter sclerotherapy may contribute to a higher survival rate than TIPS in patients with Child-Pugh class A disease.

Analysis of Variance↗
PubMed2004

[Peptic ulcer recurrence after successful eradication of Helicobacter pylori--clinical characteristics and management].

Peptic ulcer recurrence after successful eradication of Helicobacter pylori(H. pylori) is not rare. We evaluated the effect of H. pylori eradication on prevention of gastric ulcer recurrence. Ulcer recurrence had occurred in 20 of 256 H. pylori-eradicated patients, and most of ulcer recurrence were found within 1 year after eradication. NSAIDs and psychological stress, but not sex, smoking habit, drinking habit, and past history of ulcer, seem to be associated with ulcer recurrence. Intractable ulcers after the eradication of H. pylori frequently recurred. Some recurrent ulcers were refractory to treatment with H2-receptor antagonists or proton pump inhibitors. The mechanism(s) by which healed ulcers recur after successful eradication of H. pylori remains unclear.

Helicobacter Infections↗
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↗