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Publications (15)31.32 Total impact

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    ABSTRACT: BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) in early gastric cancer has rapidly come into widespread use. However, since complications such as bleeding and perforation often occur, and the procedure time is longer for ESD than endoscopic mucosal resection (EMR), development of safer and more reliable technique is required. PATIENTS AND METHODS: The subjects comprised 45 patients with lesions diagnosed histologically as early gastric cancer. They were divided into three groups: cross-counter technique group (CC, n = 15), peroral traction-assisted ESD with suture material group (PT, n = 15), and no-traction group (NT, n = 15). ESD was carried out by two endoscopists who had experienced fewer than 30 cases of ESD. To compare safety and efficacy of a new traction method (CC group) for ESD in early gastric cancer with other methods (PT group and NT group), procedure time, dissected area per unit time, complete resection rate, perforation rate, and bleeding rate were evaluated. RESULTS: There was no significant difference among these three groups in terms of complications, complete resection rate or procedure time. The dissection area per unit time was 22.4, 15.7, and 13.5 mm(2)/min in the CC, PT, and NT groups, respectively, and there was a significant difference between the CC and NT groups (p = 0.007). CONCLUSIONS: The cross-counter technique shortened the treatment time for endoscopists without abundant experience in gastric ESD, and it is considered a useful method to institute in order to introduce ESD.
    Surgical Endoscopy 06/2012; · 3.43 Impact Factor
  • Endoscopy 05/2012; 44 Suppl 2:E182-3. · 5.74 Impact Factor
  • Endoscopy 05/2012; 44 Suppl 2:E225. · 5.74 Impact Factor
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    ABSTRACT: A 62-year-old man was referred to our hospital with enlargement of mucosa-associated lymphoid tissue (MALT) lymphoma of the rectum after the eradication of Helicobacter pylori. The patient was given a diagnosis of stage I MALT. Endoscopic observation revealed an enlarged rectal tumor with 3, 18 double trisomy. Rituximab monotherapy was given and complete remission was achieved. Rituximab monotherapy can be useful for MALT lymphoma of the rectum.
    Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 04/2010; 107(4):612-9.
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    ABSTRACT: Indocyanine green (ICG) is a fluorescent marker that is excited by rays at a wavelength of 768 nm to emit fluorescence at a wavelength of 807 nm in the infrared (IR) range. We developed an IR fluorescence endoscope (IRFE) to observe superficial gastric tumors and assessed its clinical usefulness. To evaluate the clinical usefulness of an IRFE for the assessment of superficial gastric tumors. An observational study. University hospital. Newly developed IRFE. Thirty patients with gastric tumors were enrolled in this study, and their lesions were subjected to endoscopic submucosal dissection (ESD), or laparoscopic gastrectomy after observation with the IRFE. Gastric lesions were subjected to conventional observation, followed by IR fluorescence observation before and after intravenous ICG (0.01 mg/kg) injection. The relationship between the positive fluorescence and invasivity of each tumor. Fluorescence was positive in 8 of 10 gastric cancers with submucosal invasion (80%) and 1 of 20 adenomas or intramucosal gastric cancers (5%); the difference was statistically significant (P<.01). IRFE is a useful diagnostic tool for estimating the invasivity of gastric tumors.
    Gastrointestinal Endoscopy 07/2007; 66(1):37-43. · 5.21 Impact Factor
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    ABSTRACT: Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.
    Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 04/2007; 104(3):401-6.
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    ABSTRACT: The present study evaluated correlations between preoperative bile juice cytology and mucin expression of surgical specimens in biliary tract carcinoma. Twenty-five patients with biliary tract carcinoma surgically treated at our hospital, whose bile juice cytology had been evaluated before operation, were allocated to this study. Biliary cytology was classified into three categories based on the Papanicolaou classification. Immunohistochemical staining of tissues was performed using MUC1 and MUC2 monoclonal antibodies. Lesions showing MUC1 expression of ++ or higher and MUC2 expression of - were classified as Group A, and the remaining lesions as Group B. According to the epithelial site, preoperative cytology was highly correlated in Group A, while it was negative in Group B (p<0.05). In the advanced site of carcinomas, preoperative cytology tended to highly be positive in Group A, while it tended to be negative in Group B (p<0.05). These results suggest that the bile juice cytology results are affected by characteristics of mucin expression in the tissue. Based on the possibility that mucin expression correlates with the prognosis of each carcinoma, a positive cytological result suggests a poor prognosis for the carcinoma, which may be informative for predicting the post-operative courses and choosing treatments.
    The Journal of Medical Investigation 02/2007; 54(1-2):41-7.
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    ABSTRACT: Background In previous studies, we generated infrared ray fluorescence-labeled monoclonal antibodies and developed an infrared ray fluorescence endoscope capable of detecting the monoclonal antibodies to establish a novel diagnostic technique for gastrointestinal cancer. Although the whole IgG molecule has commonly been used for preparation of labeled antibodies, labeled IgG displays insufficient sensitivity and specificity, probably resulting from non-specific binding of the Fc fragment to target cells or interference between fluorochromes on the identical labeled antibody, which might be caused by molecular structure. In this in vitro study, we characterized an Fc-free fluorescence-labeled Fab fragment, which was expected to yield more specific binding to target cells than the whole IgG molecule. Methods An anti-mucin antibody and ICG-ATT, an ICG derivative, were used as the labeled antibody and labeling compound, respectively. Paraffin sections of excised gastric cancer tissues were subjected to staining. The labeled whole IgG molecule (ICG-ATT-labeled IgG) and the labeled Fab fragment (ICG-ATT-labeled Fab) were prepared according to a previous report, and the fluorescence properties, antibody activities, and features of fluorescence microscope images obtained from paraffin sections were compared. Results Both ICG-ATT-labeled Fab and ICG-ATT-labeled IgG were excited by a near infrared ray of 766 nm, and maximum emission occurred at 804 nm. Antibody activities of ICG-ATT-labeled Fab were shown to be similar to those of unlabeled anti-MUC1 antibody. The fluorescence intensity obtained from paraffin sections of excised gastric cancer tissues revealed a tendency to be greater with ICG-ATT-labeled Fab than with ICG-ATT-labeled IgG. Conclusions The infrared ray fluorescence-labeled Fab fragment was likely to be more specific than the conventionally labeled antibodies. Fragmentation of antibodies is considered to contribute to improved sensitivity and specificity of labeled antibodies for detection of micro gastrointestinal cancers.
    Photodiagnosis and Photodynamic Therapy 09/2006; 3(3):177-183. · 2.24 Impact Factor
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    ABSTRACT: Since there is no infrared fluorescence materials in the living body, infrared fluorescence labeling materials are very useful for making a diagnosis of a micro cancer. We have developed an infrared fluorescence endoscope (IRFE) and indocyanin green (ICG)-derivative as infrared fluorescence labeling materials to evaluate gastrointestinal neoplastic lesions. The study aims were to apply an IRFE and to demonstrate its usefulness in detecting cancerous tissue using an antibody coupled with ICG-derivative. IRFE consisted of an infrared endoscope equipped with excitation (710-790 nm) and barrier (810-920 nm) filters and an intensified CCD camera. We have developed ICG N-hydroxy sulfo succinimide ester (ICG-sulfo-OSu) and 3-ICG-acyl-1, 3-thiazolidine-2-thione (ICG-ATT) as an infrared fluorescent-labeling reagent. ICG-derivative-labeled mouse anti-human carcinoembryonic antigen (CEA) antibody and MUC1 antibody were employed in this study. Moreover, we examined the ability of a reinforcement agent, octylglucoside, to intensity fluorescence from the labeled antibody. Biopsy specimens of gastric cancer were stained with anti-CEA antibody by the avidin-biotinylated peroxidase complex method. Among the positive specimens, freshly resected stomach from three cases were used for the infrared (IR) imaging analysis. The incubation of freshly resected stomach specimens with ICG-anti-CEA antibody-complex resulted in positive staining of the tumor sites by IRFE, and the IR fluorescent images correlated well with the tumor sites. The immunohistochemical studies suggested that the intensity of IR fluorescence of ICG-ATT-MUC1 was stronger than that of ICG-sulfo-OSu. In tumor sections, the reinforcement agent intensified fluorescence, ever at low antibody concentrations. Therefore, we conclude that an anti-CEA (and/or MUC1) antibody with affinity for cancerous lesions and labeled with ICG-derivative can be imaged with this IRFE. Specific antibodies tagged with ICG-derivative with the reinforcement agent can label cancer cells and generate a strong enough fluorescent signal to detect small cancers when examined with an IR fluorescence endoscope.
    The Journal of Medical Investigation 03/2006; 53(1-2):1-8.
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    ABSTRACT: In recent years, labeled antibodies have been used for diagnostic imaging in many studies. In this study, we investigated the mode of binding in antibodies labeled with ICG derivatives newly developed for the diagnosis of microcarcinomas, and evaluated the optimal binding molar ratio between the labeling compounds and antibody. MUC 1 antibody and ICG derivatives (ICG-ATT and ICG-sulfo-OSu) were used. ICG derivatives non-covalently bound to the antibody were removed with ethyl acetate, and the ratio of ICG derivatives covalently bound to the labeled antibody was confirmed. During purification of the labeled antibody, the amount of each labeling compound reacting with 1 molecule of the antibody varied as follows: 4, 8, 16, and 32 molar equivalents. Subsequently, the intensity of fluorescence was evaluated by spectroscopy and infrared fluoroscopy. The ratio of residual ICG derivative labeling the antibody was 67.4% for ICG-ATT and 65.0% for ICG-sulfo-OSu. When fluorescent antibody labeled with ICG-ATT at an F/P ratio of 2.94 or 4.18 was used, specific and clear fluorescent images of the antigen were obtained. When ICG-ATT-labeled antibody at an F/P ratio of 6.50 or 6.75 was used, the fluorescence intensity decreased and the fluorescent images of antigen became unclear. It was found that the ICG-ATT-labeled antibody was a more specific and sensitive marker than ICG-sulfo-OSu-labeled antibody, and that lower binding molar ratios of ICG-ATT were more useful for labeling the antibody.
    The Journal of Medical Investigation 03/2006; 53(1-2):52-60.
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    ABSTRACT: Mucin core proteins are known to be present in various organs and are specifically expressed with carcinogenesis and closely associated with the prognoses of various malignant tumors in the digestive tract such as colorectal cancer. The present study evaluated correlations between mucin and p53 expression and prognosis of gallbladder cancer using surgically resected tissue specimens from 26 patients with gallbladder carcinoma surgically treated at our hospital. Immunohistochemical staining was performed using MUC 1, MUC2, and p53 monoclonal antibody. The level of antigen expression in the lesion was classified into four stages: none(-), slight(+), moderate (++), and severe (+ + +). According to the UICC classification, histopathological grading, levels of T, N, and M factors, and tumor stages were compared with regard to the correlations with mucin and p53 expression. All cases were classified into two groups according to the results of mucin immunohistochemistry: group A (MUC1, > or = ++; and MUC2, < or = +) and group B (MUC1, < ++; or MUC2, > +). Postoperative survival periods were compared between the two groups and p53-positive and -negative groups. Neither histological grading nor T factor correlated with mucin or p53 expression, respectively. Moreover, neither N factor nor M factor correlated with mucin or p53 expression. Furthermore, stage grouping did not correlate with mucin or p53 expression. However, when the correlation between the postoperative survival period and mucin expression was evaluated, the mean postoperative surgical period was significantly shorter in Group A than in Group B (1.02 years in Group A vs 2.92 years in Group B; P = 0.016). There was no relationship between postoperative survival period and p53 positivity. Mucin expression was independent of various tumor growth factors and clearly reflected the prognosis of gallbladder cancer. Because the relative malignancy of gallbladder cancer could be evaluated by examining the level of glycoprotein expression in tumor tissue, mucin could be a more important marker than p53 for predicting prognosis in gallbladder carcinoma using surgically resected tissue specimens.
    Digestive Diseases and Sciences 08/2005; 50(8):1410-3. · 2.26 Impact Factor
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    ABSTRACT: We have developed an infrared fluorescence endoscope to evaluate gastrointestinal vascular lesions. Infrared endoscopy (IRE) after intravenous administration of indocyanine green (ICG) is used at present to examine vascular lesions such as esophageal varices. However, no previous study has compared the sensitivity of infrared fluorescence endoscopy (IRFE) with that of IRE. In this study, we compared the usefulness of IRFE and IRE. For IRFE we used an infrared endoscope equipped with excitation and barrier filters and an intensified charge-coupled device camera. In preliminary experiments, the observable tissue depth was assessed by wrapping increasing numbers of layers of commercially available pork around a syringe containing a uniform concentration of ICG or by changing the concentration of ICG in a syringe covered by a piece of pork of uniform thickness. In the clinical part of the study, ICG was administered intravenously at different concentrations to patients with esophageal varices and the resulting infrared fluorescent images were evaluated. The preliminary experiments revealed that the depth of tissue that could be visualized was significantly greater in IRFE than it was in IRE (11.2 mm in IRFE vs. approximately 3.2 mm in IRE). Clear infrared fluorescence was obtained by IRFE at lower concentrations of ICG than the concentrations required to obtain clear images using IRE. In the clinical part of the study, clear infrared fluorescence was observed in a region where esophageal varices had been detected by conventional endoscopy when ICG was administered in doses of 0.005 mg/kg to 0.01 mg/kg, which was lower than the doses used in IRE. Compared with conventional IRE, IRFE facilitated the observation of deeper layers, and esophageal varices were observed by IRFE following the intravenous administration of a markedly reduced dose of ICG. IRFE, in combining the characteristics of reflected infrared light and fluorescence, may be a useful novel procedure in the diagnosis of vascular lesions in the gastrointestinal tract.
    Endoscopy 02/2005; 37(1):52-7. · 5.74 Impact Factor
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    ABSTRACT: An infrared fluorescence endoscope (IRFE) was used to evaluate several kinds of gastrointestinal lesions under indocyanine-green (ICG) administration. It may be useful as a novel diagnostic procedure for vascular lesions occurring in the gastrointestinal tract.
    Biophotonics, 2004. APBP 2004. The Second Asian and Pacific Rim Symposium on; 01/2005
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    ABSTRACT: We have developed infrared fluorescence endoscope (IRFE) and ICG-derivative as infrared fluorescence labeling materials. Specific antibodies tagged with ICG-derivative with the reinforcement agent can label cancer cells and can generate a strong enough fluorescent signal to detect small cancers when examined with an IRFE.
    Biophotonics, 2004. APBP 2004. The Second Asian and Pacific Rim Symposium on; 01/2005
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    ABSTRACT: A 64-year-old man with a chief complaint of melena visited our emergency outpatient clinic. After several examinations, he was diagnosed as a gastrointestinal stromal tumor (GIST) with liver metastasis. Surgical resection of the jejunal lesion and postoperative adjuvant therapy with STI571 for one year was performed. Due to recent immunohistological studies and introduction of STI571, the diagnosis, treatment, and prognosis of GIST are about to change profoundly. Further accumulation of cases is necessary to investigate the diagnosis, treatment, and prognosis of GIST.
    Internal Medicine 01/2005; 43(12):1151-6. · 0.97 Impact Factor