Duodenal cancer diagnosed by capsule endoscopy and double balloon enteroscopy in a patient with hereditary nonpolyposis colorectal cancer.
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Biomedical subjects
Publications and source records attributed to Nobuhide Oshitani.
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Human neutrophils underwent spontaneous apoptosis, which was accompanied by degradation of Mcl-1, but not other anti-apoptotic molecules (cIAP1, cIAP2, A1, survivin and Bcl-2). Spontaneous neutrophil apoptosis and Mcl-1 degradation were prevented by cyclic AMP (cAMP) agonists (dibutyryl cAMP and prostaglandin E(1)), and the effects of cAMP agonists on neutrophils were highly resistant to cycloheximide, a protein synthesis inhibitor, although slight increase in Mcl-1 mRNA expression was induced by cAMP agonists. Proteasome inhibitors (epoxomicin and lactacystin) also prevented spontaneous neutrophil apoptosis and Mcl-1 degradation to the same extent as cAMP agonists, and no additive effect was obtained by combination of cAMP agonists and proteasome inhibitors. These findings suggest that cAMP agonists, like proteasome inhibitors, delay neutrophil apoptosis primarily via stabilization of Mcl-1.
Abnormalities in humoral immunity are implicated in the pathogenesis of ulcerative colitis. However, the detailed mechanisms of B-cell activation in the locale remain unaccounted for. We analyzed ulcerative colitis from the standpoint of lymphocytic expansion in the loco. Intestinal specimens obtained at surgery from 30 patients with ulcerative colitis treated with corticosteroids and 15 with Crohn's disease were analyzed by immunohistochemistry and flow cytometry. Ulcerative colitis was characterized by a diffuse distribution of Ki-67(+) small round cells particularly in the ulcer base (that were CD19(+) and CD20(-)), with a significant number of them also CD138(+). Immunoelectron microscopy for CD19 revealed an abundance of rough endoplasmic reticulum in the cytoplasm. These indicated that they are of immature plasma lineage cells. By contrast, plasma cells in Crohn's disease were negative for CD19, and the labeling for Ki-67 was infrequent, showing mature phenotype. Flow cytometry revealed an occurrence of CD19(+) and CD20(-) cells in ulcerative colitis but not in Crohn's disease. The labeling index of Ki-67 among CD19(+) plasma cells was positively correlated with the clinical activity of ulcerative colitis. High labeling of Ki-67 in CD19(+) plasma cells is specific for active ulcerative colitis that was resistant to medical treatment by corticosteroids.
A 74-year-old woman was referred to our department because of epigastralgia. Endoscopic findings revealed yellowish bumpy mucosa from the bulbus to the second portion of the duodenum. The patient was admitted to our hospital for further examinations and treatment for this lesion. Endoscopic mucosal resection (EMR) was performed on part of the lesion to obtain the final diagnosis, and then mucosa-associated lymphoid tissue (MALT) lymphoma of the duodenum was diagnosed using this procedure. In this case, no evidence of Helicobacter pylori infection in the patient's stomach was detected by any of the diagnostic examinations used, such as the urea breath test, histological study, culture, and serological antibody. For this reason, the patient's duodenal MALT lymphoma was treated solely with long-term clarithromycin, which had an inhibitory action on lymphocyte activation. The lesion showed slight improved during the first 12 days of treatment, and complete regression was reached after 6 months of treatment. It is suggested that the long-term use of clarithromycin may be effective for diseases of the gastrointestinal tract associated with the lymphocyte proliferation.
BACKGROUND: Neutrophils are considered to play a causative role in inflammatory mucosal injury in ulcerative colitis (UC), and an association between platelets and neutrophils may contribute to the progression of the inflammatory processes. To test this hypothesis, we performed immunohistochemical and flow cytometric analyses on tissue and blood samples from patients with UC. MATERIALS AND METHODS: Colonic mucosal tissues of patients with active (n = 27) or inactive (n = 16) UC and normal controls (n = 11) were subjected to immunohistochemical staining for markers of activated platelets (glycoprotein IIb/IIIa and P-selectin) and neutrophils (neutrophil elastase, myeloperoxidase, and CD66b). The amounts of stained cells were evaluated by computer-aided morphometry. Peripheral blood samples from patients (n = 8) and healthy volunteers (n = 8) were subjected to comparative flow cytometric analysis of activated platelets. RESULTS: P-selectin-positive activated platelets were frequently aggregated in the inflamed mucosa, especially in ulcerative lesions, and were close to regions of dense neutrophil infiltration. An increase in the number of activated platelets in the colonic lesions was associated with an increase in infiltrating neutrophils and was related to the severity of the disease. The flow cytometric analysis indicated that circulating platelets of patients with UC were highly activated. CONCLUSIONS: The present study demonstrated that a close association between activated platelets and neutrophils is a prominent pathological change in both the affected colonic mucosa and peripheral blood of patients with active-phase UC. This suggests that platelet-neutrophil association may play an important role in the progression of inflammatory processes in UC.
OBJECTIVES: Double-balloon enteroscopy (DBE) enables inspection of deep small bowel, and total small bowel examination can be performed by either antegrade or retrograde DBE. The aim of this study was to evaluate ileal involvement, which cannot be achieved using conventional colonoscopy, by DBE in patients with Crohn's disease. METHODS: From December 2003 to September 2005, a total of 44 patients with Crohn's disease underwent 53 examinations using DBE. RESULTS: Forty patients with Crohn's disease, seven women and 33 men, underwent DBE, and the ileum was investigated in 38 patients. There were 25 cases of ileitis, 2 of colitis, and 13 of ileocolitis. Jejunal lesions were found in two and ileal lesions proximal to the terminal ileum were found in 24 patients with Crohn's disease. DBE was superior to radiological study to detect aphthae, erosions, and small ulcers in the ileum. Small bowel stricture was demonstrated in six and nine patients with DBE and small bowel barium study (SBBS), respectively. An additional mucosal finding was demonstrated in one of the eight patients who underwent wireless capsule endoscopy, and one patient had a capsule removed by DBE that had become lodged because of an ileal stricture. One ileal perforation because of overtube balloon pressure occurred in 53 examinations of patients with Crohn's disease (1.9%). CONCLUSION: DBE is useful to evaluate small bowel lesions in patients with Crohn's disease; however, special attention should be paid to mesenteric longitudinal ulcers during insertion and the overtube balloon should not be inflated if a clear intestinal view is not possible.
A 32-year-old woman visited our department because of repeated regurgitation of food, and was diagnosed with rumination syndrome based on possession of symptoms typical for it. Although rumination syndrome is classified as a functional esophageal disorder according to the Rome II criteria, it is not well known in Japan, and there have been no previous reports of it in an adult with normal intelligence. Since patients with rumination syndrome are often misdiagnosed and receive unnecessary treatment, awareness of it by physicians is important.
Irritable bowel syndrome may be consisted of several subsets of functional disorders including a subset of post inflammatory and post infectious disorders. Animal models revealed prolonged hyper-kinesis of the intestinal muscle and visceral hyperalgesia in adult mice previously received phychological stress or bowel irritation in neonatal period. Murine infectious experiment reproduced adult post infectious functional disorders. Involvement of acute phase Th2 cytokine production and prolonged TGFbeta1 production contribute to intestinal hyper-kinesis in post nematode infectious rat model. Pathogenesis of irritable bowel syndrome may be further subdivided by the results of experimental models, and a novel therapeutic approach is expected from such experimental models.
Epidermal growth factor (EGF) is predominantly secreted by salivary glands and activates Na(+)/H(+) exchanger-1 (NHE-1), which regulates intracellular pH (pH(i)). We investigated the roles of EGF and NHE-1 in esophageal epithelial defense against acid using human esophageal epithelial cell lines and a rat chronic esophagitis model. Esophageal epithelial cells were incubated with acidified medium in the absence or presence of EGF. Cell viability and changes in pH(i) were measured. Chronic acid reflux esophagitis was induced in rats with and without sialoadenectomy. Esophageal lesion index, epithelial proliferation, and expression of EGF receptors and NHE-1 were examined. EGF protected esophageal epithelial cells against acid in a dose-dependent manner, and the cytoprotective effect of EGF was completely blocked by treatment with NHE-1 inhibitors. Tyrosine kinase, calmodulin, and PKC inhibitors significantly inhibited cytoprotection by EGF, whereas MEK, phosphatidylinositol 3-kinase, and PKA inhibitors had no effect. EGF significantly increased pH(i) recovery after NH(4)Cl pulse acidification, and this increase in pH(i) recovery was significantly blocked by inhibitors of calmodulin and PKC. Sialoadenectomy led to an increase in the severity of chronic esophagitis but affected neither epithelial proliferation nor expression of EGF receptors. Expression of NHE-1 mRNA was increased in esophagitis and upregulated in rats with sialoadenectomy. The increasing severity of esophagitis in rats with sialoadenectomy was prevented by exogenous administration of EGF. In conclusion, EGF protects esophageal epithelial cells against acid through NHE activation via Ca(2+)/calmodulin and the PKC pathway. Deficiency in endogenous EGF is associated with increased severity of esophagitis. EGF and NHE-1 play crucial roles in esophageal epithelial defense against acid.
Rebamipide, a gastro-protective drug, was developed in Japan for the treatment of peptic ulcer disease. It was proven superior to the former same category drug cetraxate in a randomized, controlled, double-blind, comparative clinical study in 1989. Rebamipide's mechanisms of actions are different from anti-secretory drugs; it accelerates and improves the quality of ulcer healing and reduces ulcer recurrence rate. Numerous studies have been conducted to explain the mechanisms responsible for these actions, 37 papers were published by 1998. Major properties of rebamipide include: stimulation of prostaglandin and mucus glycoprotein synthesis, inhibition of reactive oxygen species, inflammatory cytokines and chemokines, and inhibition of neutrophils activation. Since 1998, 107 papers were published, clarifying further effects of rebamipide on cyclooxygenase-2, prostaglandin E receptors, growth factors (i.e., HGF, EGF, and VEGF), heat-shock proteins, nitric oxide, adhesion molecules, neutrophils, and Helicobacter pylori- and NSAID-related pathology. Moreover, inhibitory action of rebamipide on gastric cancer growth has also been shown. In this issue we reviewed recent advances in understanding of rebamipide's mechanism of action and its newest clinical applications.
Rebamipide is an antiulcer drug capable of various actions including the induction of cyclooxygenase-2 (COX-2). In this study, we investigated the effect of rebamipide on gastric ulcer healing in COX-2-deficient mice. Wild-type (N=34) and COX-2-deficient mice (N=28) with gastric ulcers were administered 30 mg/kg of rebamipide or the vehicle. Ulcerous tissues were subjected to measurements of ulcer size, immunohistochemical staining of CD31 (an endothelial cell marker), and mRNA levels. COX-2 deficiency delayed ulcer healing and inhibited angiogenesis and bFGF mRNA expression in the granulation tissue. In wild-type mice, rebamipide accelerated ulcer healing and increased COX-2 mRNA expression. In COX-2-deficient mice, rebamipide prevented delayed ulcer healing and reversed the inhibition in angiogenesis and bFGF mRNA expression. The effect of rebamipide on the enhancement of ulcer healing, angiogenesis, and induction of bFGF expression was more prominent in wild-type mice than in COX-2-deficient mice. In conclusion, rebamipide may accelerate gastric ulcer healing through both COX-2-dependent and COX-2-independent mechanisms.
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.
OBJECTIVE: It is generally recommended that patients with gastro-esophageal reflux disease (GERD) refrain from eating within 3 h of going to sleep. In addition to a remarkable lack of supporting clinical evidence, whether GERD patients have shorter dinner-to-bed time is unknown. This study was designed to determine a possible association between dinner-to-bed time and GERD, compared with healthy adults. METHODS: In a matched case-control study, we enrolled 147 GERD patients, and age- and sex-matched 294 controls without GERD symptoms such as heartburn and acid regurgitation during the previous year. Dinner-to-bed time, defined as the time intervals until going to bed after finishing eating dinner, was examined by a self-report questionnaire. Logistic regression was used to calculate odds ratio (OR) and 95% confidence intervals (CI) for GERD. RESULTS: After adjustment for smoking habits, drinking habits, and body mass index, shorter dinner-to-bed time was significantly associated with an increased OR of GERD (p < 0.0001) and the OR for patients whose dinner-to-bed time was less than 3 h was 7.45 (95% CI 3.38-16.4) compared with patients whose dinner-to-bed time was 4 h or more. These observations were consistent in both patients with non-erosive GERD and erosive esophagitis, and there was no significant difference in dinner-to-bed time intervals between non-erosive GERD and erosive esophagitis. CONCLUSION: In this matched case-control study, shorter dinner-to-bed time was significantly associated with an increased OR for GERD.
OBJECTIVE: Helicobacter pylori infection and atrophic gastritis are inversely related to erosive esophagitis. Whether these factors affect the pathogenesis of endoscopy-negative reflux disease is not clear. We aimed to elucidate the differences in clinical characteristics between endoscopy-negative erosive disease and erosive esophagitis. METHODS: 253 subjects (89 with endoscopy-negative reflux disease and 164 with erosive esophagitis) were studied. Gastric atrophy was assessed by measurement of serum pepsinogen. Logistic regression was used to calculate the odds ratio (OR) and 95% confidence intervals (CI) of endoscopy-negative reflux disease compared with erosive esophagitis. RESULTS: Among GERD patients, female gender (OR = 2.27, 95% CI, 1.25-4.10), smoking (OR = 0.45, 95% CI, 0.22-0.91), and the presence of hiatal hernia (OR = 0.30, 95% CI, 0.17-0.56) were significantly associated with endoscopy-negative reflux disease compared with male gender, not smoking, and absence of hiatal hernia, respectively. Body mass index (BMI) was also significantly associated with a decreased OR for endoscopy-negative reflux disease. Although H. pylori infection and gastric atrophy were significantly more common in patients with endoscopy-negative reflux disease, these associations did not persist in a multiple-adjustment model. After adjustment for gender, BMI, smoking, and hiatal hernia, a decrease in serum pepsinogen I/II ratio was significantly associated with an increased OR for endoscopy-negative reflux disease (p for trend = 0.018). CONCLUSIONS: Female gender, low BMI, not smoking, absence of hiatal hernia, and severity of gastric atrophy were positively associated with endoscopy-negative reflux disease compared with erosive esophagitis among Japanese patients.
Activator protein-1 (AP-1) is a transcription factor that consists of either a Jun-Jun homodimer or a Jun-Fos heterodimer. AP-1 regulates the expression of multiple genes essential for cell proliferation, differentiation and apoptosis. Numerous reports suggest that AP-1 plays an important role in various human diseases. Among them, the roles relating to human cancers have been strongly suggested for a long time. In human cancers, colorectal cancer is still a leading cause of morbidity and mortality in the world. Since there are some reports about the role of AP-1 in colorectal cancer response to a number of stimuli, such as cytokines and growth factors, and oncogenictransformation, therapeutic inhibition of AP-1 activity has attracted considerable interest. Here, we demonstrate the biological properties of AP-1 and its role in colorectal cancer, and discuss a possibility of an AP-1 inhibitor, an adenovirus dominant-negative mutant of c-Jun, as a therapeutic agent for gene therapy.
Functional oesophageal epithelial defense, including cell proliferation, restitution, buffers and ion transporters, plays a significant role in maintaining mucosal integrity and enabling rapid repair after injury. Growth factors such as epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha), hepatocyte growth factor (HGF) and keratinocyte growth factor (KGF) are associated with oesophageal epithelial proliferation or restitution. Na+/H+ exchanger-1, an ion transporter, regulates intracellular pH and cell volume, and may have roles in cell proliferation, migration and survival. Cytokine, adhesion molecules, cyclooxygenase-2 and free radicals are associated with oesophageal inflammation and breach of the functional epithelial defense. Although the oesophagus does not have strong functional epithelial defense against acid, this defensive mechanisms may be involved in the pathogenesis of non-erosive gastro-oesophageal reflux disease. Medical therapy may be developed in future to enhance functional oesophageal epithelial defense.
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.
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.