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Biomedical subjects

Ken Haruma

Publications and source records attributed to Ken Haruma.

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

Cardiac glands hyperplastic polyp of the stomach.

Reported herein is a very rare polyp in the gastric cardia of a 49-year-old man. He was referred because of a polyp detected by upper gastrointestinal examination in an affiliated hospital. Endoscopic examination revealed a polyp-like submucosal tumor. Endoscopic ultrasonography revealed minute cystic dilatations and thickening of the submucosal layer. Accordingly, a preliminary diagnosis of cardiac gland hyperplasia was made. The lesion was removed successfully by snare polypectomy. Observed macroscopically, the polyp was 30 mm in diameter and covered with normal gastric mucosa. Examined histologically, the polyp comprised a hyperplastic submucosal cardiac gland.

Cardia↗
PubMed2005

Evaluation of bowel ischemia with contrast-enhanced US: initial experience.

PURPOSE: To prospectively evaluate the accuracy of contrast material-enhanced ultrasonography (US) in the depiction of bowel ischemia in patients with radiographic evidence of small-bowel dilatation. MATERIALS AND METHODS: The ethics committee approved this study, and informed consent was obtained from all patients. Fifty-one patients (34 men and 17 women; mean age, 67.1 years) with evidence of small-bowel dilatation at conventional radiography were enrolled. Twenty patients had bowel ischemia (15 cases of bowel strangulation and five of thromboembolism of the superior mesenteric artery) and 31 patients had simple obstruction. After injection of SHU-508A, the most dilated or the least peristaltic bowel segments were imaged at contrast-enhanced power Doppler US (interval, 4 seconds) for 2 minutes. Color signals obtained in the bowel wall were classified as normal, diminished, or absent. Contrast-enhanced US and classification of color signals were performed by a sonologist. The US systems were equipped with 3-12-MHz transducers. Fisher exact test was used to evaluate the significance of the differences between each group of patients, and P < .01 was considered to indicate a significant difference. RESULTS: The color signals were absent in five patients with superior mesenteric arterial thromboembolism and in seven patients with strangulation, were diminished in five patients with strangulation, and were normal in three patients with strangulation and in 31 patients with simple obstruction. By pooling the absent and diminished color signals together as a diagnostic indicator of bowel ischemia, the sensitivity was 85% (95% confidence interval [CI]: 62.1%, 96.8%), the specificity was 100% (95% CI: 90.8%, 100%), the positive predictive value was 100% (95% CI: 83.8%, 100%), the negative predictive value was 91.2% (95% CI: 76.3%, 98.1%), the likelihood ratio for a positive test result was infinity, and the likelihood ratio for a negative test result was 0.15 (95% CI: 0.032, 0.379). CONCLUSION: Contrast-enhanced US shows promise for the noninvasive diagnosis of bowel ischemia based on initial experience in patients with radiographic evidence of small-bowel dilatation.

Aged↗
PubMed2005

[Pathophysiology of Barrett's esophagus--motility disorder of esophagus].

Barrett's esophagus is a premalignant condition of reflux esophagitis and the prevalence is increasing in western countries. Although pathogenesis of Barrett's esophagus is still unknown, several studies have indicated that Barrett's esophagus is related to increased acid reflux through decreased lower esophageal sphincter tone and reduced esophageal contractions. In this article recent studies of Barrett's esophagus on pathophysiology of esophageal motility is reviewed.

Barrett Esophagus↗
PubMed2004

Clinicopathologic and endoscopic features of colorectal serrated adenoma: differences between polypoid and superficial types.

BACKGROUND: Serrated adenoma is a distinct histologic colorectal lesion. There are two macroscopic types: polypoid and superficial. The aim of this study was to clarify clinicopathologic and endoscopic differences between polypoid and superficial serrated adenomas. METHODS: An analysis was conducted of the clinicopathologic and endoscopic features for 240 polypoid and 127 superficial serrated adenomas examined by colonoscopy, and the surface pit patterns of 114 polypoid and 64 superficial serrated adenomas examined by magnifying videoendoscopy. RESULTS: The male:female gender ratio for the polypoid serrated adenomas (3.5:1) was significantly higher than that for the superficial serrated adenomas (1.7:1). Superficial serrated adenomas were significantly larger than polypoid serrated adenomas (mean [standard deviation], respectively, 10.1 [7.9] mm vs. 6.3 [4.6] mm). In the distal segments of the colorectum, polypoid serrated adenomas were more common than superficial serrated adenomas. Granulonodular and lobular appearances at endoscopy were significantly more common for polypoid (23.3%) than for superficial serrated adenomas (7.1%). Pit patterns differed between the lesion types: polypoid serrated adenomas had type III(L) or IV pit patterns; all superficial serrated adenomas had the type II pit pattern. The relative frequency of occurrence of high-grade dysplasia and carcinoma in situ among superficial serrated adenomas (25.2%) was significantly greater than that among polypoid serrated adenomas (9.2%). The tubulovillous growth pattern was significantly more common in polypoid tumors (31.5%) than in superficial tumors (0%). CONCLUSIONS: Polypoid and superficial serrated adenomas have different clinicopathologic characteristics and growth patterns.

Adenoma↗
PubMed2004

Initial experience with catheter probe US when using a multibending endoscope.

BACKGROUND: High-frequency catheter probe US provides detailed images when the scanning plane is perpendicular to the area of interest and the latter is within the focal zone. A multibending endoscope has been developed that has two bending sections that can be deflected independently. The aim of this study was to determine whether this new endoscope enhances high-frequency catheter probe US. METHODS: High-frequency catheter probe US was performed with the multibending endoscope in 33 patients with upper-GI lesions. The endoscope was carefully maneuvered until the scanning plane was perpendicular to the area of interest and the target area was within the focal zone of the probe. The effects of deflecting the second bending section on the image and on the rotating elements in the probe were evaluated. RESULTS: For 28 lesions, no improvement was observed with use of both bending sections. However, for 5 lesions, the US image was improved by use of the second bending section. These lesions were located in the stomach on the lesser or greater curve. In no instance did deflection of both bending sections result in uneven rotation of the mechanical elements in the probe. CONCLUSIONS: For certain lesions, US images obtained with a catheter probe can be improved by using an endoscope with a second bending section.

Catheterization↗
PubMed2004

Magnifying colonoscopic features of ulcerative colitis reflect histologic inflammation.

BACKGROUND: Colonoscopy plays an important role in the diagnosis of ulcerative colitis and the determination of disease activity. Standard colonoscopic findings, however, do not often agree with histologic findings. The aim of this study was to clarify the relation between magnifying colonoscopic features and histologic inflammation in the course of ulcerative colitis. METHODS: We performed magnifying colonoscopy examinations in 60 patients with ulcerative colitis. We classified the features into six types and analyzed the relations among these features, standard colonoscopic features (Matts grades), and pathohistological findings. RESULTS: It was difficult to distinguish the remission stage from the active stage by standard colonoscopy in cases of Matts grade 2 disease. There was a relation, however, between the magnifying colonoscopic types and the degrees of histologic inflammation. The magnifying colonoscopic types reflected histologic inflammation status more accurately than did standard colonoscopic findings. CONCLUSION: Magnifying colonoscopy is useful for determining the degree of histologic change without biopsy in patients with ulcerative colitis.

Adult↗
PubMed2004

Recurrent peptic ulcers in patients following successful Helicobacter pylori eradication: a multicenter study of 4940 patients.

OBJECTIVE: Although curative treatment of Helicobacter pylori infection markedly reduces the relapse of peptic ulcers, the details of the ulcers that do recur is not well characterized. The aim of this study is to describe the recurrence rate and specific features of peptic ulcers after cure of H. pylori infection. METHODS: This was a multicenter study involving 4940 peptic ulcer patients who were H. pylori negative after successful eradication treatment and were followed for up to 48 months. The annual incidence of ulcer relapse in H. pylori-cured patients, background of patients with relapsed ulcers, time to relapse, ulcer size, and site of relapsed ulcers were investigated. RESULTS: Crude peptic ulcer recurrence rate was 3.02% (149/4940). The annual recurrence rates of gastric, duodenal and gastroduodenal ulcer were 2.3%, 1.6%, and 1.6%, respectively. Exclusion of patients who took NSAIDs led annual recurrence rates to 1.9%, 1.5% and 1.3%, respectively. The recurrence rate was significantly higher in gastric ulcer. Recurrence rates of patients who smoked, consumed alcohol, and used NSAIDs were significantly higher in those with gastric ulcer recurrence compared to duodenal ulcer recurrence (e.g. 125 of 149 [83.9%] relapsed ulcers recurred at the same or adjacent sites as the previous ulcers). CONCLUSIONS: Curative treatment of H. pylori infection is useful in preventing ulcer recurrence. Gastric ulcer is more likely to relapse than duodenal ulcer. Recurrent ulcer tended to recur at the site of the original ulcers.

Alcohol Drinking↗
PubMed2004

Chromosomal and microsatellite instability in sporadic gastric cancer.

BACKGROUND: Gastric cancer can progress through two pathways of genomic instability: chromosomal (CIN) and microsatellite instability (MSI). It is hypothesized that these two pathways are not always independent and that some tumors show overlap between these two mechanisms. METHODS: A total of 98 sporadic gastric cancers were classified based on their MSI status, using microsatellite assay with BAT26. Evidence for CIN was investigated by identifying loss of heterozygosity (LOH) events on chromosome arms, 5q, 10p, 17p, 17q, and 18q, which are regions harboring tumor suppressor genes that are significant in gastric cancer development. RESULTS: Twelve tumors (12%) showed high-frequency MSI (MSI-H). Overall, 43 of the tumors (44%) had at least one LOH event, with most frequent chromosomal losses observed on 10p and 18q (30%, respectively), followed by 5q (21%), 17p (14%), and 17q (12%). Interestingly, overlap was observed between CIN and MSI pathways. Of 43 cancers with LOH events, four (9%) were also MSI-H. It was also found that 48% of cancers without MSI-H had no LOH events identified, comprising a subgroup of tumors that were not representative of either of these two pathways of genomic instability. CONCLUSION: These results suggest that molecular mechanisms of genomic instability are not necessarily independent and may not be fully defined by either the MSI or CIN pathways in sporadic gastric cancers.

Adult↗
PubMed2004

Mucin phenotype and background mucosa of intramucosal differentiated-type adenocarcinoma of the stomach.

OBJECTIVES: Gastric carcinomas have been divided into differentiated (intestinal) and undifferentiated (diffuse) types. Recently, classification studies based on mucin expression have revealed that some differentiated-type carcinomas are of a gastric phenotype. In this study, we investigated the clinicopathological features of differentiated-type adenocarcinomas and evaluated the background mucosa of the stomach based on mucin expression by the tumors. METHODS: Seventy-six intramucosal differentiated-type adenocarcinomas of the stomach were evaluated macroscopically and histologically. The mucin expression of tumor cells was examined by immunohistochemical staining with monoclonal antibodies against human gastric mucin (45M1), class III mucin (HIK1083), small intestinal mucinous antigen (SIMA-4D3), and MUC2 (Ccp58). Tumors were classified by phenotype as gastric (G-type), intestinal (I-type), mixed (M-type), or null (N-type). Not only the clinicopathological features but also the background mucosa of the stomach of G-type and I-type carcinomas were compared histologically and serologically. RESULTS: Seventeen tumors (22.4%) were classified as G-type, 31 (40.8%) as I-type, 22 (28.9%) as M-type, and 6 (7.9%) as N-type. The frequencies of elevated type tumors and papillary adenocarcinomas and the ratio of moderately/well-differentiated adenocarcinomas were higher in G-type than in I-type carcinomas. The scores for glandular atrophy and intestinal metaplasia were higher and the scores for chronic inflammation, polymorphonuclear neutrophil activity, and the density of Helicobacter pylori were lower in G-type than in I-type tumors. The serum level of pepsinogen I and the pepsinogen I/II ratio were significantly lower in G-type than in I-type tumors. CONCLUSIONS: G-type carcinoma is the predominant phenotype of papillary adenocarcinoma. The background mucosa of G-type carcinoma is associated with glandular atrophy and intestinal metaplasia, whereas that of I-type carcinoma is associated with active and chronic inflammation induced by H. pylori infection.

Adenocarcinoma↗
PubMed2004

Expression of human telomerase reverse transcriptase mRNA in esophageal cancers and precancerous lesions.

Telomerase activity confers immortality to cells through stabilization of chromosomes and contributes to the development of most human cancers. Human telomerase reverse transcriptase (hTERT) is a catalytic subunit of telomerase. Expression of hTERT mRNA has been reported to be correlated with telomerase activity. The purpose of this study was to investigate localization of hTERT mRNA in human esophageal precancerous and cancerous lesions by in situ mRNA hybridization with avidin-biotin staining. Ki-67 immunoreactivity was also examined. We analyzed 51 squamous cell carcinomas, 9 dysplasias and 60 normal mucosae. The integrity of mRNA in each sample was verified with a poly-d(T)20 probe. Seventy-eight samples (65%), including 35 carcinomas, 4 dysplasias and 39 normal mucosae, contained intact mRNA. At the single-cell level, hTERT was expressed at high levels in both the cytoplasm and nucleus. In all cases, the majority of cancer and dysplastic cells showed high levels of hTERT expression. In all 39 normal mucosae, basal cells expressed hTERT mRNA, and this was also observed in infiltrating lymphocytes. The distribution of cells expressing hTERT was similar to that of Ki-67-positive cells. These results suggest that overexpression of hTERT mRNA may be correlated with proliferative activity reflected by Ki-67 immunoreactivity and is an early event in carcinogenesis of the esophagus.

Carcinoma, Squamous Cell↗
PubMed2004

Clinical significance of angiopoietin-2 expression at the deepest invasive tumor site of advanced colorectal carcinoma.

Angiopoietin (Ang)-2 and vascular endothelial growth factor (VEGF) are thought to be critical regulators in tumor angiogenesis. We investigated the clinical significance of Ang-2 expression at the deepest invasive tumor site under the influence of VEGF expression in relation to angiogenesis, invasive/metastatic potential, and prognosis of advanced colorectal carcinoma (CRC). One hundred and fifty-two patients who underwent surgical resection for advanced CRC were enrolled in this study. Ang-2 and VEGF expression were examined immunohistochemically. Tumor microvessel density (MVD) was examined by immunohistochemical staining against CD34. Ang-2 and VEGF were expressed at the deepest invasive tumor site in 90 (59.2%) and 64 (42.1%) of 152 lesions, respectively. Patients with Ang-2 expression at the deepest invasive tumor site showed significantly (p<0.01) more frequent poorly histologic grade (71.9%), lymphatic involvement (65.9%), venous involvement (69.1%), lymph node metastasis (75.0%), liver metastasis (80.0%) and advanced disease (Dukes' stage C, 70.2%; stage D, 80.0%) than patients without Ang-2 expression. MVD was not significantly up-regulated by Ang-2 expression alone at the deepest invasive tumor site but was significantly up-regulated by VEGF expression at the deepest invasive tumor site under the positive-Ang-2 condition. In patients treated by curative surgery, patients with tumors showing both positive-Ang-2 and positive-VEGF condition at the deepest invasive tumor site had significantly poorer prognoses than patients with tumors under other conditions. Multivariate analysis with logistic regression for 5-year survival in cases of curative surgery showed that lymph node metastasis, VEGF expression and Ang-2 expression were significant factors to predict poor prognosis. Our results suggest that Ang-2 expression in collaboration with VEGF expression at the deepest invasive tumor site may result in tumor angiogenesis and that these angiogenic factors at the deepest invasive tumor site may be correlated with invasive/malignant potential and prognosis of advanced CRC.

Adenocarcinoma↗
PubMed2004

Frequent loss of heterozygosity on chromosome 10p14-p15 in esophageal dysplasia and squamous cell carcinoma.

High frequencies of loss of heterozygosity (LOH) on chromosome 10p14-p15 have been reported in various tumors, including glioma, pulmonary carcinoid and cervical, hepatic and prostatic carcinomas. These findings suggest the presence of a tumor suppressor gene at the loci. However, analysis of LOH on chromosome 10p14-p15 in esophageal tumors has not been reported. Therefore, we examined LOH on chromosome 10p14-p15 in 88 esophageal squamous cell carcinomas (SCC) (35 superficial- and 53 advanced-types) and 44 dysplasias by microsatellite assay. Five oligonucleotide primer sets for microsatellite loci D10S191, D10S501, D10S559, D10S558 and D10S249 were used. In dysplasias, frequent LOH was detected with markers D10S191 (26%) and D10S249 (33%). In superficial esophageal SCCs, frequent LOH was detected with markers D10S191 (26%), D10S559 (50%), D10S558 (29%) and D10S249 (33%). In advanced esophageal SCCs, we found frequent LOH was detected with markers D10S191 (38%), D10S501 (25%) and D10S559 (30%). There were no significant correlations between LOH on chromosome 10p14-p15 and clinicopathologic features, including patient age, sex, tumor location, depth of invasion and lymph node metastasis. These data suggest that a putative tumor suppressor gene for esophageal carcinogenesis may be located on chromosome 10p14-p15 and that malfunction of this gene may be involved in the development but not progression of esophageal tumors.

Adult↗
PubMed2004

[Reflux esophagitis--Japan and Western countries].

Although reflux esophagitis (RE) is a common disease of the upper gastrointestinal tract in Western countries, its prevalence is still low in Asian countries, including Japan. On the other hand, the prevalence of H. pylori infection and atrophic gastritis are very high in Japan in comparison to that of other developed countries. Atrophic gastritis decreases gastric acid secretion, which is much lower in the Japanese compared to that in Western persons. The main mechanism of RE is reflux of gastric acid into the esophagus from the stomach. A decrease in gastric acid secretion induced by atrophic gastritis might prevent this acid reflux. This may be the reason RE is an uncommon disease in Japan.

Asian People↗