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H Tajiri

Publications and source records attributed to H Tajiri.

At least 19 recordsLinked to original sources
PubMed2006

Clinical and endoscopic characterization of depressed gastric adenoma.

BACKGROUND AND STUDY AIM: Depressed gastric adenoma remains poorly characterized because it is rare, and is infrequently detected by endoscopy. The aim of this study was to elucidate clinical and endoscopic characteristics of depressed adenoma of the stomach. PATIENTS AND METHODS: 95 consecutive patients who underwent endoscopic resection of gastric adenomas were studied. Gastric adenomas, diagnosed according to the Vienna classification, were endoscopically classified into two types: depressed and protruding adenomas. In order to clarify endoscopic features of gastric adenomas, we performed indigo carmine chromoendoscopy as well as magnifying endoscopy with narrow band imaging, which yields clear images of mucosal microvasculature. RESULTS: 12% of 100 gastric adenomas resected from 95 patients were depressed adenomas. Age and gender were comparable between patients with each type. Depressed adenomas (15.9 +/- 6.2 mm) were significantly larger in diameter than protruding adenomas (10.6 +/- 8.0 mm) (P = 0.01). Half of depressed adenomas were reddish in color, whereas only 18% of protruding adenomas were reddish. Magnifying endoscopy with narrow band imaging showed that 71% of depressed adenomas had a regular ultrafine network pattern of mucosal microvasculature, which was not seen in protruding adenomas. Intramucosal carcinomas were more frequently found in depressed adenomas (25%) than in protruding adenomas (4.5%). CONCLUSIONS: In comparison with protruding adenomas, depressed adenomas were rare and appeared endoscopically as large and reddish with a specific regular ultrafine network pattern of mucosal microvasculature. Depressed adenomas should be endoscopically resected because intramucosal carcinomas were found in a quarter of them.

Adenoma↗
PubMed2006

A novel double-channel therapeutic endoscope ("R-scope") facilitates endoscopic submucosal dissection of superficial gastric neoplasms.

BACKGROUND AND STUDY AIM: Endoscopic submucosal dissection (ESD) is a new and radical treatment for superficial gastrointestinal neoplasms that provides high rates of en bloc resection compared with treatment by conventional mucosal resection. However, ESD is a complex procedure that is associated with long operating times and a higher complication rate. This feasibility study assessed the use of a novel double-channel therapeutic endoscope for performing en-bloc ESD in order to assess whether the procedure time could be shortened. PATIENTS AND METHODS: The therapeutic endoscope we used (the "R-scope") is equipped with a multibending system and has two movable instrument channels: one moves a grasping forceps vertically for lesion countertraction; the other swings a cutting knife horizontally for dissection. Twenty consecutive patients (18 men, 2 women; mean age 63 years, range 54 - 80 years) with superficial gastric neoplasms in the distal two-thirds of the stomach underwent resection of their tumor by ESD using the R-scope. Forty size- and location-matched gastric neoplasms resected by conventional ESD were reviewed retrospectively for the purposes of comparison. RESULTS: The rates of curative en-bloc resection, complications, and local recurrence using the two ESD methods were comparable. The mean +/- SD operating time was significantly shorter for ESD using the R-scope than for conventional ESD (57.9 +/- 29.7 minutes vs. 92.8 +/- 58.9 minutes, P = 0.016). CONCLUSION: The R-scope appears to shorten the operating time of ESD with comparable efficacy and complication rates.

Aged↗
PubMed2004

Pathological features and genetic alterations in colorectal carcinomas with characteristics of nonpolypoid growth.

We sought to clarify pathological features and genetic alterations in colorectal carcinomas with characteristics of nonpolypoid growth. Colorectal carcinomas resected at Showa University Hospital in Tokyo included 86 with characteristics of polypoid growth (PG) and 21 with those of nonpolypoid growth (NPG). Mutations of APC, Ki-ras, and p53 genes, as well as microsatellite instability (MSI), were analysed using fluorescence-based polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP). Carcinomas with an NPG pattern were smaller than PG tumours (P<0.0001). Carcinomas with a PG pattern were more likely to harbour Ki-ras mutations (36%) than NPG tumours (0%; P<0.0001). Mutation types in the APC gene differed significantly between PG and NPG carcinomas (P=0.0189), including frameshift mutations in 66% of PG carcinomas but no NPG carcinomas. Presence of a p53 mutation at a 'hot spot' also was more likely in PG carcinomas (37%) than in NPG carcinomas (0%; P=0.0124). No significant difference in presence of MSI was evident between carcinomas with PG and NPG patterns. In conclusion, significant genetic differences were evident between carcinomas with PG and NPG patterns. Genetic changes in NPG carcinomas differed from those of the conventional adenoma-carcinoma sequence. Assuming that some nonpolypoid growth lesions transform rapidly into advanced carcinomas, 20% of all colorectal carcinomas may progress in this manner.

Adult↗
PubMed2004

The effectiveness of a new multibending scope for endoscopic mucosal resection.

BACKGROUND AND STUDY AIMS: Each year at our institution we have been performing over 100 endoscopic mucosal resections (EMRs) for gastric tumor. However, there are some tumor locations where it is difficult to carry out this procedure, such as the lesser curvature or posterior wall of the gastric body, the cardia, and the lesser curvature of the antrum. To facilitate EMR of tumors in these locations, a multibending scope (the "M-scope", Olympus GIF-2T240M; Olympus Optical, Tokyo, Japan) has been developed, which has two independently curving segments. The aim of this study was to evaluate the effectiveness of this new multibending scope for EMR of gastric tumors. PATIENTS AND METHODS: Using the M-scope, we carried out EMR in 59 patients at the Jikei University Hospital. The lesions were located in the cardia in seven patients, in the gastric body in 30 patients, and in the antrum in 22 patients. The effectiveness of the M-scope was evaluated by experienced endoscopists; a score of 1 was given for very good effectiveness, and a score of 0 was given when there was no notable difference in effectiveness from the conventional scope. Evaluation was done according to the location of the lesions, the method used for EMR, and the tumor diameter. When the score for each item was equivalent to the average overall score for all the procedures or higher, the M-scope was defined as being effective. RESULTS: The overall score for all the procedures was 0.7 +/- 0.4 (average +/- SD) (very good in 43 procedures; no notable difference in 16 procedures). When assessed according to the location of the lesion, the mean effectiveness scores of the M-scope for lesions at the following locations were higher than the average overall score: the lesser curvature of the antrum (0.8 +/- 0.5); the posterior wall of the gastric body (1.0 +/- 0.0); the greater curvature of the gastric body (1.0 +/- 0.0); and the lesser curvature of the gastric body (0.9 +/- 0.4). The results suggested that the M-scope was effective for EMR of gastric tumors at these traditionally difficult locations. With regard to the scores assessed according to the method of EMR, the mean scores were 0.8 +/- 0.4 for the two-channel scope method and 0.9 +/- 0.4 for EMR using an insulated-tip diathermic knife (IT-EMR), again suggesting that the M-scope was effective for EMR by these methods. When evaluated according to tumor size, the score was 0.8 +/- 0.4 when the tumor was 11 mm or greater in diameter, indicating that the M-scope was effective for EMR of large tumors. CONCLUSION: The results of the study suggest that the M-scope is effective for EMR of tumors in the lesser curvature of the antrum, and in the posterior wall, lesser curvature, or greater curvature of the gastric body. With regard to the method of EMR, the M-scope is effective for both the two-channel scope method and IT-EMR. In relation to tumor size, the M-scope is effective for the resection of large tumors.

Adenoma↗
PubMed2004

Use of the curved linear-array echo endoscope to identify gastrorenal shunts in patients with gastric fundal varices.

BACKGROUND AND STUDY AIMS: : Balloon-occluded retrograde transvenous obliteration (B-RTO) has emerged as an effective, minimally invasive treatment for fundal varices. B-RTO requires a spontaneously developed gastrorenal shunt as a pathway for the balloon catheter to reach the fundal varices. We used a curved linear-array (CLA) echo endoscope in patients with fundal varices to identify gastrorenal shunts, and compared the detection rate with the gold standard, contrast-enhanced computed tomography (CECT). PATIENTS AND METHODS: A total of 40 patients with fundal varices were examined with both CLA echo endoscopy and CECT. The CECT images were retrospectively and independently evaluated by two gastroenterologists who were unaware of the clinical details, including the results of the CLA echo endoscopy. RESULTS: CLA echo endoscopy identified gastrorenal shunts in 26/40 patients with fundal varices. It visualized the shunt in a longitudinal direction and provided images of the connections of the shunt at both ends, the fundal varices and the left renal vein/branch of the inferior adrenal vein. The kappa index for CLA echo endoscopy and CECT for the identification of gastrorenal shunt was 0.9 (95 % CI, 0.6 to 1.0). When the cutoff point for the diameter of the gastrorenal shunt detected by the CLA echo endoscope was set at equal to or greater than 5 mm, the kappa index was 1.0 (95 % CI, 0.7 to 1.0). CONCLUSIONS: These results suggest that CLA echo endoscopy can successfully identify gastrorenal shunt and provide detailed morphological information. It also efficiently identifies patients suitable for B-RTO, particularly in cases of acute bleeding. It also has considerable potential for providing detailed information with regard to the treatment of gastric varices.

Adult↗
PubMed2004

Magnifying endoscopy combined with narrow band imaging system for early gastric cancer: correlation of vascular pattern with histopathology (including video).

BACKGROUND AND STUDY AIMS: The narrow band imaging (NBI) system consists of a sequential electronic endoscope system and a source of light equipped with new narrow band filters, yielding very clear images of microvessels on mucosal surfaces. The aim of this prospective study was to measure the correlation between the magnified images obtained with the NBI system and the histological findings, especially with regard to the vascular pattern. In addition, three-dimensional images of microvessels were reconstructed using a laser scanning microscope. PATIENTS AND METHODS: Between July 2001 and August 2003, 165 patients with depressed-type early gastric cancer lesions were enrolled in the study. The lesions were carefully observed with magnification using the NBI system. The images, the pathological characteristics of the lesions, and three-dimensionally reconstructed images of the microvascular networks in biopsied specimens were carefully analyzed. The microvascular patterns were classified into three groups: A, fine network; B, corkscrew; and C, unclassified pattern. The endoscopic images were compared with the histological findings. RESULTS: Of the three types of filter available for use with the NBI system, microvascular formation was best enhanced in B mode images produced using short wavelengths, which focus on the superficial mucosal layer. Among 109 cases of differentiated adenocarcinoma, the group A microvascular pattern was observed in 72 cases (66.1 %). Among 56 cases of undifferentiated adenocarcinoma, the group B pattern was observed in 48 cases (85.7 %; P = 0.0011) The microvascular structure observed using the NBI system corresponded with the superficial mucosal layer in the three-dimensional images obtained using laser scanning microscopy and the resected specimens. CONCLUSIONS: Magnifying endoscopy performed in combination with the NBI system is not sufficient to replace conventional histology, but is capable of predicting the histological characteristics of gastric cancer lesions.

Adenocarcinoma↗
PubMed2004

Narrow-band imaging in the diagnosis of colorectal mucosal lesions: a pilot study.

BACKGROUND AND STUDY AIMS: A newly developed narrow-band imaging (NBI) technique, in which modified optical filters were used in the light source of a video endoscope system, was applied during colonoscopy in a clinical setting. This pilot study evaluated the clinical feasibility of the NBI system for evaluating colorectal lesions. PATIENTS AND METHODS: A total of 43 colorectal lesions in 34 patients were included in the study. The quality of visualization of colorectal lesions and the accuracy of differentiation between neoplastic and non-neoplastic lesions using the NBI system were evaluated in comparison with results from conventional colonoscopy and with chromoendoscopy. RESULTS: For pit pattern delineation, NBI was superior to conventional endoscopy (P < 0.001), but inferior to chromoendoscopy (P < 0.05). NBI achieved better visualization of the mucosal vascular network and of the hue of lesions than conventional endoscopy (P < 0.05). However there was no significant difference between NBI and chromoendoscopy in differentiating neoplastic from non-neoplastic lesions (both techniques had a sensitivity of 100 % and a specificity 75 %). This was better than the results of conventional colonoscopy (sensitivity 83 %, specificity 44 %; P < 0.05 for specificity). CONCLUSIONS: These results suggest that in the examination of colonic lesions the NBI system provides imaging features additional to those of both conventional endoscopy and chromoendoscopy. For distinguishing neoplasms from non-neoplastic lesions, NBI was equivalent to chromoendoscopy.

Aged↗
PubMed2004

The aging/precancerous gastric mucosa: a pilot nutraceutical trial.

The aim of this study was to test the effect of antioxidant supplementation on enzymatic abnormalities and free radical-modified DNA adducts associated with premalignant changes in the gastric mucosa of elderly patients with HP-negative atrophic gastritis (CAG). Sixty patients with atrophic gastritis and intestinal metaplasia underwent a nutritional interview and a gastroscopy with multiple biopsy samples in the antrum that were processed for histology and for assaying: alpha-tocopherol, MDA, xanthine oxidase (XO), ornithine decarboxylase (ODC), and 8-OHdG. Patients were randomly allocated into three matched groups and supplemented for 6 months with (1) vitamin E, 300 mg/day; (2) multivitamin, two tablets t.i.d.; and (3) Immun-Age 6 g/day nocte (ORI, Gifu, Japan), a certified fermented papaya preparation with basic science-validated antioxidant/immunomodulant properties. Ten dyspeptic patients served as controls. Histology and biochemistry were blindly repeated at 3 and 6 months. CAG patients showed a significantly (P <.05) increased level of mucosal MDA and XO concentration that were reverted to normal by each supplementation (P <.05). All supplements caused a significant decrease of ODC (P <.01), but Immun-Age yielded the most effective (P < 0.05) and was the only one significantly decreasing 8-OhdG (P < 0.05). These data suggest that antioxidant supplementation, and, namely, Immun-Age, might be potential chemopreventive agents in HP-eradicated CAG patients and especially in the elderly population.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2003

A phase I study of S-1 combined with weekly cisplatin for metastatic gastric cancer in an outpatient setting.

A dose-escalation study was conducted for patients with metastatic gastric cancer to determine the recommended dose of weekly intravenous (i.v.) cisplatin combined with a fixed dose of a new oral dihydropyrimidine dehydrogenase-inhibitory fluoropyrimidine, S-1, on an outpatient basis. Secondary endpoints were to define the toxicity profile and to determine tumour responses. S-1 was fixed at a dose of 70 mg/m(2)/day and was administered for 2 weeks followed by a 1-week rest. Three dose levels of cisplatin (10, 15 and 20 mg/m(2)) were studied. Cisplatin was infused over 30 min on days 1 and 8. 20 patients were enrolled. No dose-limiting toxicities (DLTs) were recorded during the administration of cisplatin up to 20 mg/m(2), except for grade 3 diarrhoea and stomatitis in one patient at dose level 3. No grade 4 adverse events occurred. However, grade 2 gastrointestinal adverse reactions, such as nausea and anorexia, were seen in 7 of 13 patients at dose level 3 within the first two treatment cycles. This was determined to be the maximum acceptable level that would not negate the advantages observed with use of an oral drug such as S-1. An objective tumour response was seen at all dose levels, and the overall response rate in the 18 patients evaluated was 61%. A higher response rate of 78% was observed in 9 patients who had received no prior chemotherapy. Oral S-1 with weekly cisplatin is a feasible and promising combination regimen that is appropriate for an outpatient setting. A randomised phase II study comparing this combination with S-1 alone in chemo-nai;ve patients is warranted.

Adult↗
PubMed2002

Routine endoscopy using a magnifying endoscope for gastric cancer diagnosis.

BACKGROUND AND STUDY AIMS: It has been reported that the fine mucosal patterns of the gastric pits can be observed with magnification and this may assist in preliminary evaluation prior to histological diagnosis. The aim of this prospective study was to clarify the relationship between the fine mucosal patterns of gastric lesions and histological findings, and also to evaluate the usefulness of magnifying endoscopy during routine endoscopy. PATIENTS AND METHODS: A recently developed magnifying video endoscope, which enables magnification up to 80 times, was used for gastrointestinal endoscopy in 318 patients between January 2000 and January 2001, at the National Shikoku Cancer Center. In total, 232 lesions were detected. However, patients diagnosed by conventional endoscopy as having advanced gastric cancer, malignant lymphoma, or submucosal tumor were excluded from the study. The endoscopic findings for 211 lesions included in this study were compared with the histological findings. RESULTS: Coarse and irregular mucosal patterns were observed in elevated-type cancers by magnifying endoscopy, and in depressed-type cancers there was a finer pit pattern than in the surrounding mucosa, destruction or disappearance of the mucosal microstructure, and abnormal capillary vessels. The magnifying endoscopy results were closely related to the mucosal microstructure observed by dissecting microscopy and to the histological features. The rate of presumptive diagnosis of small gastric cancers was significantly higher when a magnifying endoscope was used compared with conventional endoscopy. In this study, the sensitivity and specificity of magnifying endoscopy as a diagnostic method were 96.0% and 95.5%, respectively. CONCLUSIONS: The fine mucosal patterns and the features of capillary vessels, which were identified with the magnifying endoscope, correlated well with the pathological diagnosis. Magnifying endoscopy will be very useful in predicting the histological diagnosis during routine endoscopic procedures.

Gastric Mucosa↗
PubMed2001

Structural features of a wheat plastome as revealed by complete sequencing of chloroplast DNA.

Structural features of the wheat plastome were clarified by comparison of the complete sequence of wheat chloroplast DNA with those of rice and maize chloroplast genomes. The wheat plastome consists of a 134,545-bp circular molecule with 20,703-bp inverted repeats and the same gene content as the rice and maize plastomes. However, some structural divergence was found even in the coding regions of genes. These alterations are due to illegitimate recombination between two short direct repeats and/or replication slippage. Overall comparison of chloroplast DNAs among the three cereals indicated the presence of some hot-spot regions for length mutations. Whereas the region with clustered tRNA genes and that downstream of rbcL showed divergence in a species-specific manner, the deletion patterns of ORFs in the inverted-repeat regions and the borders between the inverted repeats and the small single-copy region support the notion that wheat and rice are related more closely to each other than to maize.

DNA, Chloroplast↗
PubMed2001

Detection of early gastric cancer by a real-time autofluorescence imaging system.

A light-induced fluorescence endoscopy in the gastrointestinal tract system was used in 52 patients with 54 lesions (33 early gastric cancers, 21 benign lesions) to assess its ability to detect early gastric cancer. Comparing the images with the histological findings, 21 of the 33 carcinomas appeared dark red, ten had a mixed pattern of dark red and white, and two could not be detected. Of the 21 benign lesions, 18 appeared light blue, as do normal mucosa, with this system. In 85% of the cancer lesions (28/33), cancer extension was correctly detected. The sensitivity and specificity were 94 and 86%, respectively. Real-time autofluorescence endoscopy is a useful adjunct to conventional white-light endoscopy for detecting early gastric cancer.

Carcinoma↗
PubMed2001

A 13C-urea breath test in children with helicobacter pylori infection: assessment of eradication therapy and follow-up after treatment.

PURPOSE: Our aim was to evaluate the usefulness of the 13C-urea breath test (UBT) for the diagnosis of Helicobacter pylori infection, for assessment of the efficacy of eradication therapy, and for post-treatment follow-up in children. METHODS: Seventy-two patients who underwent endoscopy for symptoms related to the upper gastrointestinal tract were examined by rapid urease test, histology, and culture. The patients were also studied with serology and UBT. RESULTS: Forty-seven of the 72 patients were diagnosed with H. pylori infection, based on the results of biopsy-based tests and serology. As an initial diagnostic test to detect H. pylori infection, the sensitivity of the UBT was 95%, which was comparable with that of histology (94%), rapid urease test (96%), and serology (91%) and was greater than that of culture (79%). The specificity of the UBT was 100%, which was comparable with that of the other four tests. The efficacy of eradication therapy was assessed by biopsy-based tests and the UBT in 24 H. pylori-positive patients. For this purpose, the sensitivities of UBT and histology were 100%, while the sensitivities of culture and the rapid urease test were 88%. The specificity was 100% for all of these tests. Eleven patients were assessed by biopsy-based tests and UBT after more than 6 months of post-treatment follow-up. There were no discordances between the results of the UBT and those of the biopsy-based tests in any of the patients. CONCLUSIONS: The UBT may be useful for detecting H. pylori infection in children with upper gastrointestinal tract symptoms, for assessment of the efficacy of eradication therapy, and for the follow-up evaluation of patients after the therapy.

Adolescent↗
PubMed2001

Macroscopic typing with wall stricture sign may reflect tumor behaviors of advanced colorectal cancers.

No appropriate macroscopic classification of advanced colorectal cancers (A-CRC) is available for assessing their tumor behavior. In the present study, A-CRC were classified macroscopically as either stricture or nonstricture type, and the differences in clinicopathological features, mode of recurrence, and prognosis between the two types were investigated. The subjects were 166 patients with A-CRC invading beyond the muscular layer who had undergone curative surgical resection. Fresh resected specimens from these patients were used for the study. The A-CRC were classified as of stricture or nonstricture type according to whether or not they showed marked fold convergence and/or stricture of the intestinal tract (more than 30% wall shrinkage) that had the appearance of a "bow tie". Of the 166 A-CRC, 47 (28%) were classified as stricture type. This type was significantly more frequent in the colon (37%; 37/101) than in the rectum (15%; 10/65) (P = 0.003). The stricture type was more frequently associated with an abundance of fibrosis than the nonstricture type (76%; 28/37 vs 39%; 25/64 in colon; P < 0.001; 100%, 10/10 vs 42%, 23/55 in rectum; P < 0.001). The recurrence rate was also higher in the stricture type than in the non-stricture type in both the colon (51%, 19/37 vs 17%, 11/64; P = 0.003) and rectum (80%, 8/10 vs 38%, 21/55; P = 0.01). The time to recurrence was significantly shorter for the stricture type in both the colon (P < 0.001) and rectum (P = 0.02). These results indicate that the macroscopic typing of A-CRC according to the presence or absence of wall stricture sign may reflect their tumor behavior, although this behavior appears to be complex and related to tumor progression. This classification could be important clinically to assess tumor behavior in a simple way.

Aged↗
PubMed2001

Sequential methotrexate and 5-fluorouracil therapy for gastric cancer patients with peritoneal dissemination: a retrospective study.

BACKGROUND: Most gastric cancer patients with peritoneal dissemination have been excluded from clinical studies because they usually have no measurable lesions. They also have a high risk of toxicity because of complications such as intestinal obstruction and ascites. We conducted a retrospective analysis to evaluate the efficacy and feasibility of sequential methotrexate (MTX) and 5-flurorouracil (5FU) therapy for this population. METHODS: This analysis was based on 56 consecutive chemotherapy-naive patients with confirmed peritoneal dissemination of gastric cancer who were being treated with sequential MTX/5FU. The therapy comprised a weekly schedule of MTX 100 mg/m2, given as a bolus infusion 3 h prior to a bolus infusion of 5FU 600 mg/m2. Leucovorin 10mg/m2 was administered six times, every 6h, starting 24h after MTX administration. RESULTS: Evidence of peritoneal dissemination was confirmed by laparotomy in 16 patients, by cytologic examination of ascites in 11 patients, and by clinical imaging in 29 patients (15 with ascites, 13 with intestinal obstruction; in 10 of the 29 patients, detection was by barium enema or computed tomography [CT] scan). Neutropenia of grade 3 or worse and anemia were observed in 8 (14%) and 10 (18%) of the 56 patients, respectively. There was one treatment-related death due to neutropenic sepsis. Of the 26 patients with measurable lesions, 9 showed a response (36%). The median survival time and median time to treatment failure were 259 days and 167 days, respectively. Objective improvement of ascites was seen in 13 of 26 patients (50%), including 5 with showed complete disappearance of ascites. Seven of the 15 patients (47%) with intestinal obstruction showed resolution, and 8 of the 21 patients (38%) who needed nutritional support before the treatment were free of that support for a median duration of 220 days after the completion of the treatment. Forty-seven of the 56 patients (84%) could be treated at outpatient clinics. CONCLUSIONS: This regimen may be of clinical benefit for patients with peritoneal dissemination of gastric cancer.

Adult↗