85 results on '"Tomoyuki Ueki"'
Search Results
2. INI1-negative colorectal undifferentiated carcinoma with rhabdoid features and postoperative rapidly growing liver metastases: a case report and review of the literature
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Masatsugu Kojima, Toru Miyake, Tomoyuki Ueki, Hiroyuki Ohta, Ryoji Kushima, Masanori Shiohara, Hiroo Mizuta, Hiroya Iida, Tsuyoshi Yamaguchi, Sachiko Kaida, Katsushi Takebayashi, Hiromitsu Maehira, Yusuke Nishina, Tomoharu Shimizu, Eiji Mekata, and Masaji Tani
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INI1/SMARCB1 ,Colorectal undifferentiated carcinoma ,Rhabdoid feature ,Rhabdoid tumor ,Surgery ,RD1-811 - Abstract
Abstract Background Malignant tumors with rhabdoid features are extremely rare. They can occur in various organs, including the gastrointestinal tract, with common clinical features of high malignancy and poor prognosis. Case presentation A 41-year-old man visited our hospital complaining of lower abdominal pain and fever. Computed tomography (CT) revealed two wall-thickening lesions in the rectum and sigmoid colon, with the latter invading the small intestine and abdominal wall. Lymph nodes were swollen in the sigmoid mesocolon and at the roots of the inferior mesenteric artery. Colonoscopy revealed a circular type 3 lesion in the sigmoid colon and a semicircular type 2 lesion in the rectum. Biopsies of the sigmoid colon and rectum lesions revealed poorly and moderately differentiated adenocarcinoma cells, respectively. The sigmoid colon, rectum, invaded small intestine, and abdominal wall were resected; lymph node dissection was also performed. Histopathological finding of the sigmoid colon lesion revealed that the tumor cells had poor connectivity with each other, and each cell had eosinophilic cytoplasm and a polymorphic nucleus. These characteristics are termed rhabdoid features, because the morphology of these cells is similar to that of rhabdomyosarcoma tumor cells. Immunohistochemical examination showed that the tumor cells were positive for both epithelial (cytokeratin AE1/AE3) and mesenchymal cell markers (vimentin); however, they were negative for integrase interactor 1 (INI1). Therefore, the sigmoid colorectal cancer was diagnosed as an INI1-negative undifferentiated carcinoma with rhabdoid features. The patient continued to experience high fever after surgery; thus, we performed an abdominal CT scan that revealed cystic lesions in the liver 4 days after surgery. These were absent in the positron emission tomography (PET)-CT scan performed 14 days before surgery. These tumors grew rapidly, and fine needle aspiration cytology revealed that they were undifferentiated carcinomas compatible with metastatic lesions from the undifferentiated carcinoma with rhabdoid features from the sigmoid colon. Chemotherapy was administered but was not effective. The patient died 60 days after surgery. Conclusions INI1-negative colorectal undifferentiated carcinomas with rhabdoid features are extremely rare, have high histological malignancy, and a poor prognosis. Chemotherapy is not effective. Effective systemic therapy is desired.
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- 2021
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3. IgG4-related focal retroperitoneal fibrosis in ureter suggestive of colon cancer recurrence and resected laparoscopically: a case report
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Tomoyuki Ueki, Toru Miyake, Mitsuhiro Narita, Masatsugu Kojima, Sachiko Kaida, Hiroya Iida, Tomoharu Shimizu, and Masaji Tani
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IgG4-related disease ,IgG4-related focal retroperitoneal fibrosis ,Laparoscopic surgery ,Ureter ,Surgery ,RD1-811 - Abstract
Abstract Background Immunoglobulin G4-related disease (IgG4-RD) is a novel disease concept of unknown cause that is characterized by abundant infiltration of IgG4-positive cells, mass-forming lesions, and elevated serum IgG4 levels. The infiltration of IgG4-positive plasma cells and lymphocytes causes swelling, inflammation, fibrosis, and obliterative phlebitis in multiple organs. On the other hand, IgG4-RD occurring in the ureters has rarely been reported. To our knowledge, this is the first report of laparoscopic partial ureteral resection for IgG4-related focal retroperitoneal fibrosis in a ureter with suspected colon cancer recurrence. Case presentation A 72-year-old man with a history of sigmoid colon cancer visited Shiga University of Medical Science Hospital for regular follow-up in December 2019. Enhanced abdominal computed tomography revealed a mass involving the left ureter. Furthermore, fluorine-18 fluorodeoxyglucose positron emission tomography showed significant accumulation of fluorodeoxyglucose uptake in the same region. Due to the possibility of colon cancer recurrence, a laparoscopic excisional biopsy with partial ureteral resection was performed. Histologically, IgG4-positive plasma cell infiltration exceeding 10 cells per high-power field and a high ratio of IgG4-positive/IgG-positive cells exceeding 40% were observed. The postoperative serum IgG4 level was 384 mg/dL. With the application of these findings to the diagnostic algorithm in the comprehensive diagnostic criteria for IgG4-RD, the mass-forming lesion was diagnosed as definitive IgG4-related focal retroperitoneal fibrosis. Conclusions IgG4-RD should be considered in the differential diagnosis of retroperitoneal lesions. Moreover, laparoscopic surgery may be useful for making the diagnosis in difficult-to-biopsy cases.
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- 2020
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4. The impact of pharmacological thromboprophylaxis and disease-stage on postoperative bleeding following colorectal cancer surgery
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Hiroyuki Ohta, Toru Miyake, Tomoharu Shimizu, Hiromichi Sonoda, Tomoyuki Ueki, Sachiko Kaida, Tsuyoshi Yamaguchi, Hiroya Iida, and Masaji Tani
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Bleeding ,Complications ,Antithrombotic prophylaxis ,Fondaparinux ,Anoxaparin ,D-dimer ,Surgery ,RD1-811 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Pharmacological thromboprophylaxis after colorectal cancer (CRC) surgery is internationally recommended for venous thromboembolism (VTE) prevention. The aim of this retrospective study was to evaluate the risk factors of postoperative bleeding after elective surgery for patients with primary CRC receiving pharmacological thromboprophylaxis of fondaparinux or enoxaparin. Methods We experienced consecutive 266 patients who underwent elective surgery for CRC during the study period. Finally, the medical records of 218 patients with CRC administrated fondaparinux or enoxaparin following surgery were retrospectively reviewed to evaluate symptomatic VTE until 28 days and postoperative bleeding comparing perioperative D-dimer levels. Results The significant differences in TNM classification staging and type of thromboprophylaxis were observed between postoperative bleeding-negative and bleeding-positive group. There was no statistical significance among other backgrounds of patients between the two groups. One case (0.46%) of symptomatic VTE and total 11 cases (5%) of postoperative bleeding were observed. In the univariate analysis, fondaparinux thromboprophylaxis and early disease-stage CRC (stages 0 and I) were associated with risk for postoperative bleeding. Multivariate analysis revealed that fondaparinux thromboprophylaxis was identified as an independent risk factor of postoperative bleeding. Moreover, preoperative levels of D-dimer in patients with stage IV CRC were significantly higher than those with the other stages. The significant elevation in preoperative D-dimer was also observed in patients with stage II CRC compared to those with stage I CRC. Perioperative levels of D-dimer in patients with advanced disease-stage CRC (stages II, III, and IV) were significantly higher than those in patients with early disease-stage CRC. Conclusions Fondaparinux administration and early disease-stage CRC appeared to be risk factors for postoperative bleeding in patients with pharmacological thromboprophylaxis undergoing surgical treatment for CRC. Patients’ hypercoagulative condition depending on disease progression of CRC might be related to the occurrence of postoperative bleeding following CRC surgery.
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- 2019
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5. CD44-positive Cancer Stem-like Cells as a Potential Source of Peritoneal Metastasis After Surgery
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ANDREAS MICHAEL SIHOMBING, SATOSHI MURATA, MIYUKI SHIMOJI, TORU MIYAKE, KATSUSHI TAKEBAYASHI, HIROKAZU KODAMA, AYA TOKUDA, MASATSUGU KOJIMA, TOMOYUKI UEKI, NAOMI KITAMURA, MINA KITAMURA, EIJI MEKATA, and MASAJI TANI
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Cancer Research ,Oncology ,General Medicine - Published
- 2023
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6. A Case of Nuclear Protein of the Testis Midline Carcinoma Diagnosed by Staging Laparoscopy for a Descending Colon Tumor with Peritoneal Dissemination
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Kurumi Tsuchihashi, Toru Miyake, Takeru Maekawa, Tomoyuki Ueki, Masatsugu Kojima, Tomoharu Shimizu, Sachiko Kaida, Hiroya Iida, Rinko Hino, Ryoji Kushima, and Masaji Tani
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Gastroenterology ,Surgery - Published
- 2023
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7. Creep Fracture of Copper Tricrystal along Grain Boundaries
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Tatsuya Okada, Hiromu Hisazawa, Hiroki Morimoto, Kazuki Nakao, Ryuta Okubo, and Tomoyuki Ueki
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Condensed Matter Physics - Published
- 2022
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8. Carbon Deposition Assisting the Enhancement of Catalytic Activity with Time-on-Stream in the Dehydrogenation of Isobutane over NiO/Al2O3
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Shigeru Sugiyama, Tashu Yoshida, Naohiro Shimoda, Tomoyuki Ueki, Yuki Kato, and Wataru Ninomiya
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General Chemical Engineering ,General Chemistry - Published
- 2022
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9. Microscopic Structure and Binding Mechanism of the Corrosion-Protective Film of Oleylpropanediamine on Copper in Hot Water
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Haruka Yoshioka, Ken Yoshida, Naoki Noguchi, Tomoyuki Ueki, Kei-ichiro Murai, Kazuya Watanabe, and Masaru Nakahara
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General Energy ,Physical and Theoretical Chemistry ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Abstract
The structure of the film formed by oleylpropanediamine (OLDA) on the copper (Cu) metal surface in water at 150 °C was investigated by combining quantitative NMR and surface characterization methods. We succeeded in quantifying the amount of film formation by precisely determining all mass balances in the systems examined. 2D IR microscopic mapping showed that the film thickness is uneven in the horizontal direction with a length scale of ~100 μm and hundreds of OLDA layers. This film thickness was also confirmed by AFM. The analysis of the C–H stretching vibrational frequency disclosed that the alkyl chains are highly ordered in the layers close to the Cu surface and are conformationally disordered in the layers distant from the Cu surface in the thicker portion of the film. Combining XPS measurements using argon gas cluster ion beam etching with the ICP-AES analysis, we revealed that the key to multiple layering is the formation of a coordination complex of the unprotonated amino groups of OLDA with Cu that presumably results in polymer chain-like network structures. Contact angle measurements at different OLDA concentrations and treatment times showed that the water repellency of the film originated from the thick layering of OLDA molecules with disordered hydrophobic chains.
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- 2022
10. Predictors and clinical impact of postoperative diarrhea after colorectal cancer surgery: a prospective, multicenter, observational study (SHISA-1602)
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Hiroyuki Ohta, Toru Miyake, Tomoyuki Ueki, Masatsugu Kojima, Masayasu Kawasaki, Takeshi Tatsuta, Takekazu Iuchi, Sumihiro Kamitani, Tomoharu Shimizu, Eiji Mekata, and Masaji Tani
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Diarrhea ,Complications ,Postoperative Complications ,Colorectal surgery ,Rectal Neoplasms ,Gastroenterology ,Humans ,Surgical Stomas ,Prospective Studies ,Colorectal Neoplasms ,Colorectal cancer ,Digestive System Surgical Procedures ,Retrospective Studies - Abstract
Purpose:Postoperative diarrhea, including high-output stoma (HOS), frequently occurs after colorectal surgery; its risk factors and clinical implications on subsequent complications remain unknown. This study aimed to evaluate the risk factors and clinical implications of postoperative diarrhea after primary colorectal cancer (CRC) surgery., Methods: This prospective observational study included patients with CRC who underwent radical surgery at six hospitals between June 2016 and December 2017. The patients were categorized into three groups (non-stoma, colostoma, and ileostoma groups)., Results:A total of 178 patients participated in the study. In the non-stoma group, the incidence of postoperative diarrhea was 18.4% (27/147). The incidence of HOS was 28.6% (4/14) in the ileostoma group, and 0% in the colostoma group. Multivariable analyses of the incidence of diarrhea in the non-stoma group indicated that habitual smoking and hypertension were significantly associated with postoperative diarrhea (P = 0.012 and P = 0.0274, respectively). Postoperative diarrhea was more likely to occur in patients with rectal cancer than in those with colon cancer (P = 0.0501). In the non-stoma and ileostoma groups, the probability of the occurrence of other complications with Clavien-Dindo (C-D) grades II or higher was significantly higher in patients with C-D grade I diarrhea, including HOS, than in patients without diarrhea (39.3% vs. 14.6%, P = 0.0061)., Conclusions:Smoking and hypertension are the independent predictors of postoperative diarrhea after an elective CRC surgery. Rectal cancer surgery seems to be associated with postoperative diarrhea more than colon cancer surgery does. Mild postoperative diarrhea may lead to more severe complications.
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- 2022
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11. Usefulness of measuring temporal changes in physical activity levels using an accelerometer for prediction and early detection of postoperative complications after hepatectomy
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Toru Miyake, Haruki Mori, Masatsugu Kojima, Masaji Tani, Hiroya Iida, Tomoyuki Ueki, Katsushi Takebayashi, Hiromitsu Maehira, Kaori Tomida, Sachiko Kaida, and Tomoharu Shimizu
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Pleural effusion ,medicine.medical_treatment ,Physical activity ,physical activity ,Early detection ,Patient characteristics ,030230 surgery ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Accelerometry ,Ascites ,medicine ,Hepatectomy ,Humans ,skin and connective tissue diseases ,Exercise ,Retrospective Studies ,Bell curve ,Hepatology ,business.industry ,fungi ,Liver Neoplasms ,Gastroenterology ,food and beverages ,medicine.disease ,Pleural Effusion ,accelerometer ,030220 oncology & carcinogenesis ,Anesthesia ,sense organs ,medicine.symptom ,business - Abstract
Background:This research aimed to determine whether patterns of temporal changes in activity levels can indicate postoperative complications following hepatectomy., Methods:Between December 2016 and December 2019, 147 patients wore an accelerometer to measure their physical activity levels after hepatectomy until postoperative day 7. Patterns of changes in activity levels were categorized as follows: upward slope type (n = 88), wherein activity levels gradually increased; bell curve type (n = 13), wherein activity levels initially increased but subsequently decreased; and flat type (n = 46), wherein there was no apparent increase in activity levels. Patient characteristics and postoperative complications were compared for each group., Results:Postoperative complications occurred in 4.5% of patients in the upward slope group, in 76.9% in the bell curve group, and in 65.2% in the flat group (p < 0.001). Surgical site infections (SSI), refractory pleural effusion, and ascites were more common in the bell curve group, while pneumonia was only observed in the flat group., Conclusion:SSI, pleural effusion, and ascites should be considered when previously increasing activity levels decline during the postoperative period. In addition, there is a high risk of SSI and pneumonia when activity levels do not increase at all after surgery.
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- 2022
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12. Effectiveness of York-Mason Procedure for a Refractory Rectourethral Fistula that Relapsed after Repair by a Perineal Approach:A Case Report
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Masatsugu Kojima, Toru Miyake, Tomoyuki Ueki, Tomoharu Shimizu, and Masaji Tani
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Gastroenterology ,Surgery - Published
- 2022
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13. Surgical Technique and Safety of TaTME for Rectal Cancer
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Toru Miyake, Tomoharu Shimizu, Tomoyuki Ueki, Masatsugu Kojima, and Masaji Tani
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Gastroenterology ,Surgery - Published
- 2022
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14. INI1-negative colorectal undifferentiated carcinoma with rhabdoid features and postoperative rapidly growing liver metastases: a case report and review of the literature
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Hiroya Iida, Hiroo Mizuta, Toru Miyake, Masanori Shiohara, Yusuke Nishina, Hiromitsu Maehira, Katsushi Takebayashi, Masatsugu Kojima, Hiroyuki Ohta, Sachiko Kaida, Eiji Mekata, Tsuyoshi Yamaguchi, Masaji Tani, Ryoji Kushima, Tomoharu Shimizu, and Tomoyuki Ueki
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Pathology ,medicine.medical_specialty ,RD1-811 ,Colorectal cancer ,Rectum ,Case Report ,030230 surgery ,Sigmoid mesocolon ,Inferior mesenteric artery ,03 medical and health sciences ,0302 clinical medicine ,Colorectal Undifferentiated Carcinoma ,medicine.artery ,Colorectal undifferentiated carcinoma ,medicine ,Rhabdomyosarcoma ,INI1/SMARCB1 ,business.industry ,Sigmoid colon ,Rhabdoid feature ,medicine.disease ,digestive system diseases ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Adenocarcinoma ,Surgery ,Rhabdoid tumor ,business - Abstract
Background Malignant tumors with rhabdoid features are extremely rare. They can occur in various organs, including the gastrointestinal tract, with common clinical features of high malignancy and poor prognosis. Case presentation A 41-year-old man visited our hospital complaining of lower abdominal pain and fever. Computed tomography (CT) revealed two wall-thickening lesions in the rectum and sigmoid colon, with the latter invading the small intestine and abdominal wall. Lymph nodes were swollen in the sigmoid mesocolon and at the roots of the inferior mesenteric artery. Colonoscopy revealed a circular type 3 lesion in the sigmoid colon and a semicircular type 2 lesion in the rectum. Biopsies of the sigmoid colon and rectum lesions revealed poorly and moderately differentiated adenocarcinoma cells, respectively. The sigmoid colon, rectum, invaded small intestine, and abdominal wall were resected; lymph node dissection was also performed. Histopathological finding of the sigmoid colon lesion revealed that the tumor cells had poor connectivity with each other, and each cell had eosinophilic cytoplasm and a polymorphic nucleus. These characteristics are termed rhabdoid features, because the morphology of these cells is similar to that of rhabdomyosarcoma tumor cells. Immunohistochemical examination showed that the tumor cells were positive for both epithelial (cytokeratin AE1/AE3) and mesenchymal cell markers (vimentin); however, they were negative for integrase interactor 1 (INI1). Therefore, the sigmoid colorectal cancer was diagnosed as an INI1-negative undifferentiated carcinoma with rhabdoid features. The patient continued to experience high fever after surgery; thus, we performed an abdominal CT scan that revealed cystic lesions in the liver 4 days after surgery. These were absent in the positron emission tomography (PET)-CT scan performed 14 days before surgery. These tumors grew rapidly, and fine needle aspiration cytology revealed that they were undifferentiated carcinomas compatible with metastatic lesions from the undifferentiated carcinoma with rhabdoid features from the sigmoid colon. Chemotherapy was administered but was not effective. The patient died 60 days after surgery. Conclusions INI1-negative colorectal undifferentiated carcinomas with rhabdoid features are extremely rare, have high histological malignancy, and a poor prognosis. Chemotherapy is not effective. Effective systemic therapy is desired.
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- 2021
15. Creep Fracture of Aluminum and Copper Tricrystals Having 〈110〉-Tilt Σ3, 3, 9 Grain Boundaries
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Katsuya Kawaguchi, Hiromu Hisazawa, Tomoyuki Ueki, Kazuki Nakao, Tatsuya Okada, Hiroki Morimoto, Akihiro Iwasaki, and Takuro Tomita
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Materials science ,Mechanical Engineering ,chemistry.chemical_element ,Condensed Matter Physics ,Copper ,Tilt (optics) ,Creep ,chemistry ,Mechanics of Materials ,Aluminium ,Void (composites) ,Fracture (geology) ,General Materials Science ,Grain boundary ,Composite material ,Grain Boundary Sliding - Published
- 2021
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16. Preoperative physical activity level measurement by accelerometer for predicting post-hepatectomy complications: a prospective observational study
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Hiroya Iida, Hiromitsu Maehira, Haruki Mori, Katsushi Takebayashi, Masatsugu Kojima, Sachiko Kaida, Tomoyuki Ueki, Toru Miyake, and Masaji Tani
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Surgery - Abstract
Introduction Recently, accelerometers have received much attention around the world. This study examined whether preoperative physical activity level measured by an accelerometer can be a useful predictor of post-hepatectomy complications. Methods Between December 2016 and December 2020, the physical activity levels of 185 patients were measured using an accelerometer 3 days before hepatectomy and from postoperative day 1 to 7. The patients without postoperative complications (n=153) and those with postoperative complications (n=32) were compared using either the chi-square test or Fisher’s exact test for nominal variables; continuous variables were analyzed using either Student’s t-test or Mann–Whitney U test. Differences were considered statistically significant when p-value was
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- 2022
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17. Adverse impact of postoperative intra-abdominal infectious complications on cancer recurrence-related survival after curative gastric cancer surgery
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Katsushi Takebayashi, Satoshi Murata, Sachiko Kaida, Tsuyoshi Yamaguchi, Reiko Otake, Toru Miyake, Tomoyuki Ueki, Masatsugu Kojima, Hiroya Iida, Hiromitsu Maehira, Haruki Mori, Tomoharu Shimizu, and Masaji Tani
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Intraoperative bleeding ,endocrine system ,General Medicine ,biochemical phenomena, metabolism, and nutrition ,Prognosis ,Postoperative intra-abdominal infectious complications ,Postoperative complication ,Postoperative Complications ,Gastrectomy ,Stomach Neoplasms ,Humans ,Surgery ,Neoplasm Recurrence, Local ,Gastric cancer ,Aged ,Retrospective Studies - Abstract
Background:This study aimed to evaluate the impact of postoperative intra-abdominal infectious complications (PICs) on survival after surgery for gastric cancer., Methods:A total of 152 patients who underwent curative gastrectomy for gastric cancer were included. The effect of clinicopathological features and PICs on recurrence-free survival (RFS) and overall survival (OS) were investigated., Results:The median age was 67 years. The pathological stage was stage I (61), II (40), and III (51). Thirty-two patients (21.1%) had PICs: 9, pancreatic fistula; 14, anastomotic leakage; and 17, intra-abdominal abscess. The five-year RFS and OS rates were significantly lower in patients with PICs than in those without PICs (63.4 vs. 85.6%; p < 0.01 and 56.4 vs. 80.3%; p < 0.01, respectively). In multivariate analysis, intraoperative blood loss was an independent prognostic factor for PICs., Conclusions:Patients with PICs had worse clinical outcomes. Reducing intraoperative bleeding may improve the prognosis of gastric cancer.
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- 2022
18. Comparison of self‐expandable metallic stent placement followed by laparoscopic resection and elective laparoscopic surgery without stent placement for left‐sided colon cancer
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Sachiko Kaida, Tomoharu Shimizu, Masatsugu Kojima, Tomoyuki Ueki, Masaji Tani, Toru Miyake, and Hiroya Iida
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Laparoscopic surgery ,medicine.medical_specialty ,RD1-811 ,Colorectal cancer ,medicine.medical_treatment ,retrospective study ,RC799-869 ,bridge to surgery ,Self-expandable metallic stent ,medicine ,obstructive colon cancer ,Elective surgery ,propensity score matching ,business.industry ,Gastroenterology ,self‐expandable metallic stent ,Stent ,Retrospective cohort study ,Perioperative ,Original Articles ,Diseases of the digestive system. Gastroenterology ,medicine.disease ,Surgery ,Propensity score matching ,Original Article ,business - Abstract
Aim:Self‐expandable metallic stent (SEMS) placement for obstructive colon cancer is widely performed as a bridge to surgery (BTS) procedure before resection. This study aimed to investigate the surgical and oncological results of laparoscopic elective surgery with or without SEMS placement to assess the efficacy of SEMS placement as a BTS., Methods:We retrospectively analyzed consecutive patients with stage II, III, and IV left‐sided colon cancer who underwent elective laparoscopic resection between 2013 and 2019. All patients were divided into two groups: with and without SEMS placement., Results:The SEMS group included 24 patients, whereas the non‐SEMS group included 86 patients. The serum hemoglobin and albumin levels were lower (P = .049, P = .03), and the serum leukocyte and C‐reactive protein levels were higher (P < .0001, P = .022) in the SEMS group. The tumor diameter and tumor circumferential rate were higher in the SEMS group (both P < .0001). No significant differences were observed in operation time, blood loss, postoperative complications, or postoperative hospital stay. After 1:1 propensity score matching, 15 patients in the SEMS group were compared with 15 patients in the non‐SEMS group. The 3‐year overall survival rates of the SEMS and non‐SEMS groups were 87.5% and 88.9%, respectively (P = .97). The 3‐year recurrence‐free survival rates of the SEMS and non‐SEMS groups were 58.2% and 81.7%, respectively (P = .233). No significant difference was found in the sites of recurrence., Conclusion:The perioperative and long‐term outcomes of SEMS placement as a BTS before laparoscopic resection could be acceptable compared with other elective laparoscopic operations without SEMS placement.
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- 2021
19. The Comparison of Fecal Microbiota in Left-Side and Right-Side Human Colorectal Cancer
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Haruki Mori, Masashi Ohno, Sachiko Kaida, Toru Miyake, Hiromitsu Maehira, Daiki Yasukawa, Masaji Tani, Hiroya Iida, Tomoharu Shimizu, Akira Andoh, Masatsugu Kojima, Tomoyuki Ueki, and Zhang Hexun
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medicine.medical_specialty ,biology ,Colorectal cancer ,business.industry ,medicine.drug_class ,medicine.medical_treatment ,Antibiotics ,Cancer ,Gut flora ,medicine.disease ,biology.organism_classification ,Gastroenterology ,Gastrointestinal Microbiome ,Feces ,Fusobacterium ,RNA, Ribosomal, 16S ,Internal medicine ,medicine ,Humans ,Surgery ,Microbiome ,Colorectal Neoplasms ,business ,Neoadjuvant therapy - Abstract
Introduction: Microbiomes play a vital role in the development and progression of cancer. The clinical status, including prognosis, genetic mutations, and sensitivity to chemotherapy, differs depending on the location of colorectal cancer (CRC); however, the association between gut microbiota and the location of CRC is not entirely understood. This study was conducted to evaluate the differences in the gut microbiota in patients with CRC according to the location of the tumor. Methods: Fifty-six patients who underwent surgery for CRC between August 2018 and November 2019 were included in the study. Three patients who had received neoadjuvant therapy or antibiotic treatment within 1 month before surgery were excluded. The metagenomes of microbiota in preoperative feces were assessed using the V3–V4 region of 16s rRNA amplicon sequences. Results: The beta diversity of the Bray-Curtis distance was significantly higher in left-sided than in right-sided CRC. Fusobacterium predominated in left-sided CRC according to the linear discriminant analysis effect size method. Blautia, Eryspelotrichales, Holdemanella, Faecalibacterium, Subdoligranulum, and Dorea constituted the dominant intestinal flora in right-sided CRC. Pathway analysis revealed that L-lysine fermentation and cob(II)yrinate a,c-diamide biosynthesis I were predominant in left-sided CRC. Discussion: This study demonstrated that fecal microbiota in left-sided CRC constitutionally and functionally differ from those in right-side CRC. These results will help to elucidate the biological differences according to tumor location and develop treatments for human CRC.
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- 2021
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20. Successful Surgical Repair of Perineal Body for Obstetric Trauma-induced Fecal Incontinence: A Case Report
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Hiroyuki Ohta, Tomoyuki Mizukuro, Kyozo Hashimoto, Mitsuhiro Fujino, Tomoharu Shimizu, Toru Miyake, Tomoyuki Ueki, Masatsugu Kojima, Eiji Mekata, and Masaji Tani
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General Earth and Planetary Sciences ,General Environmental Science - Published
- 2021
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21. The Elevation in Preoperative Procalcitonin Is Associated with a Poor Prognosis for Patients Undergoing Resection for Colorectal Cancer
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Tomoyuki Ueki, Masatsugu Kojima, Yoshihiro Endo, Hiroyuki Ohta, Toru Miyake, Tsuyoshi Yamaguchi, Masaji Tani, Eiji Mekata, Tomoharu Shimizu, Sachiko Kaida, and Hiroya Iida
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Male ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,Poor prognosis ,mGPS ,Multivariate analysis ,Colorectal cancer ,Gastroenterology ,Procalcitonin ,Sepsis ,Internal medicine ,parasitic diseases ,Biomarkers, Tumor ,medicine ,Humans ,Clinical significance ,Stage (cooking) ,Risk factor ,Retrospective Studies ,business.industry ,Prognostic nutritional index ,Middle Aged ,Prognosis ,bacterial infections and mycoses ,medicine.disease ,Preoperative Period ,Female ,Surgery ,Colorectal Neoplasms ,Infection ,business ,hormones, hormone substitutes, and hormone antagonists - Abstract
Background:Procalcitonin (PCT) is a well-known marker for bacterial infection; however, the clinical significance of PCT in the long-term prognosis after colorectal cancer (CRC) surgery remains unclear., Methods:This is a retrospective review of 277 patients that underwent CRC surgery to investigate the relationship between preoperative PCT, clinicopathological condition, cancer-specific overall survival (OS), and relapse-free survival (RFS)., Results:Median follow-up interval was 5.0 years in all patients. Thirty-six patients developed recurrence, and 46 patients died due to recurrences or metastases of CRC. Preoperative PCT levels were highest in Stage IV patients. The cancer-specific OS in patients with Stage IV/PCT ≤0.05 ng/mL was significantly higher than those with Stage IV/PCT >0.05 ng/mL (3 years survival; 42.3 vs. 14.3%, p = 0.0413). On multivariate analysis, gender, TNM classification, and PCT were identified as significant risk factors for cancer-specific OS in patients with Stage I-III CRC. The cancer-specific OS rate of these patients with PCT ≥0.08 ng/mL, compared with PCT, Conclusion:High preoperative PCT values in CRC patients appeared to be associated with poor OS but not RFS following surgical treatments.
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- 2020
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22. [A Case of Intussusception Due to Juvenile Colorectal Cancer with Suspected Lynch Syndrome]
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Reo, Omachi, Masatsugu, Kojima, Toru, Miyake, Tomoyuki, Ueki, Hiroya, Iida, Tsuyoshi, Yamaguchi, Ken, Ishikawa, Sachiko, Kaida, Katsushi, Takebayashi, Hiromitsu, Maehira, Tomoharu, Shimizu, and Masaji, Tani
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Adult ,Male ,Young Adult ,Adolescent ,Colonic Neoplasms ,Humans ,Colorectal Neoplasms, Hereditary Nonpolyposis ,DNA Mismatch Repair ,Intussusception ,Colectomy ,Colon, Transverse - Abstract
A 20-year-old man presenting with abdominal pain and distension from 3 months ago was admitted to our hospital. Colonoscopy showed a type 1 tumor in the transverse colon. The biopsy was moderately differentiated adenocarcinoma. Abdominal enhanced CT revealed intussusception associated with the tumor. After non-invasive reduction of intussusception was performed, a full-body examination revealed no findings suggestive of distant metastases or other Lynch syndrome- related tumors. We performed laparoscopic right hemicolectomy. Lynch syndrome was suspected based on his family history, MMR protein immunohistochemistry and MSI-High, but genetic testing was rejected due to cost reasons. If young people have chronic abdominal symptoms and a family history of suspected hereditary colorectal cancer, a close examination of colon cancer should be performed.
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- 2022
23. Impact of Early Postoperative Diarrhea on Anastomotic Leakage after Laparoscopic Low Anterior Resection for Rectal Cancer
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Masaji Tani, Toru Miyake, Tomoyuki Ueki, Masatsugu Kojima, Tomoharu Shimizu, Hiroyuki Ohta, and Eiji Mekata
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medicine.medical_specialty ,Low Anterior Resection ,Colorectal cancer ,business.industry ,Anastomotic leakage ,medicine ,Postoperative diarrhea ,medicine.disease ,business ,Surgery - Published
- 2020
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24. A Case of Ileocecal Valve Lipohyperplasia Causing Intussusception
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Tomoyuki Ueki, Toru Miyake, Masatugu Kojima, Yusuke Nishina, Tomoharu Simizu, and Masaji Tani
- Subjects
medicine.medical_specialty ,Ileocecal valve ,medicine.anatomical_structure ,business.industry ,Lipohyperplasia ,Intussusception (medical disorder) ,medicine ,business ,medicine.disease ,Surgery - Published
- 2020
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25. The impact of pharmacological thromboprophylaxis and disease-stage on postoperative bleeding following colorectal cancer surgery
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Tsuyoshi Yamaguchi, Masaji Tani, Hiroyuki Ohta, Hiroya Iida, Toru Miyake, Hiromichi Sonoda, Tomoharu Shimizu, Tomoyuki Ueki, and Sachiko Kaida
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Male ,Complications ,Colorectal cancer ,Fondaparinux ,0302 clinical medicine ,Medicine ,Stage (cooking) ,Univariate analysis ,Incidence ,Venous Thromboembolism ,Middle Aged ,Prognosis ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Treatment Outcome ,Oncology ,Elective Surgical Procedures ,030220 oncology & carcinogenesis ,Disease Progression ,Female ,030211 gastroenterology & hepatology ,Colorectal Neoplasms ,medicine.drug ,medicine.medical_specialty ,lcsh:Surgery ,Postoperative Hemorrhage ,lcsh:RC254-282 ,03 medical and health sciences ,Humans ,Enoxaparin ,Risk factor ,Elective surgery ,neoplasms ,Aged ,Neoplasm Staging ,Retrospective Studies ,Antithrombotic prophylaxis ,business.industry ,Research ,Bleeding ,Anticoagulants ,Retrospective cohort study ,Perioperative ,lcsh:RD1-811 ,medicine.disease ,digestive system diseases ,Surgery ,Anoxaparin ,D-dimer ,business - Abstract
Background Pharmacological thromboprophylaxis after colorectal cancer (CRC) surgery is internationally recommended for venous thromboembolism (VTE) prevention. The aim of this retrospective study was to evaluate the risk factors of postoperative bleeding after elective surgery for patients with primary CRC receiving pharmacological thromboprophylaxis of fondaparinux or enoxaparin. Methods We experienced consecutive 266 patients who underwent elective surgery for CRC during the study period. Finally, the medical records of 218 patients with CRC administrated fondaparinux or enoxaparin following surgery were retrospectively reviewed to evaluate symptomatic VTE until 28 days and postoperative bleeding comparing perioperative D-dimer levels. Results The significant differences in TNM classification staging and type of thromboprophylaxis were observed between postoperative bleeding-negative and bleeding-positive group. There was no statistical significance among other backgrounds of patients between the two groups. One case (0.46%) of symptomatic VTE and total 11 cases (5%) of postoperative bleeding were observed. In the univariate analysis, fondaparinux thromboprophylaxis and early disease-stage CRC (stages 0 and I) were associated with risk for postoperative bleeding. Multivariate analysis revealed that fondaparinux thromboprophylaxis was identified as an independent risk factor of postoperative bleeding. Moreover, preoperative levels of D-dimer in patients with stage IV CRC were significantly higher than those with the other stages. The significant elevation in preoperative D-dimer was also observed in patients with stage II CRC compared to those with stage I CRC. Perioperative levels of D-dimer in patients with advanced disease-stage CRC (stages II, III, and IV) were significantly higher than those in patients with early disease-stage CRC. Conclusions Fondaparinux administration and early disease-stage CRC appeared to be risk factors for postoperative bleeding in patients with pharmacological thromboprophylaxis undergoing surgical treatment for CRC. Patients’ hypercoagulative condition depending on disease progression of CRC might be related to the occurrence of postoperative bleeding following CRC surgery.
- Published
- 2019
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26. Boron ion implantation on femtosecond-laser-irradiated diamond surface
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Tatsuya Okada, Kenya Bando, Fumiya Iwaasa, Tomoyuki Ueki, Hiromu Hisazawa, and Takuro Tomita
- Subjects
Physics and Astronomy (miscellaneous) ,General Engineering ,General Physics and Astronomy - Abstract
We investigated the effect of femtosecond-laser-induced surface modifications on ion incorporation into diamond crystals. The (001) surface of a diamond crystal was irradiated with femtosecond laser pulses. Boron ions were implanted on the laser-irradiated surface of two crystals: one at 600 °C and the other at room temperature. The ion concentration along the depth of the crystal was measured with secondary ion mass spectroscopy. The concentration profile was parabolic, and in the deeper region after the peak, the ion concentration was higher in the irradiated area than in the nonirradiated area in both crystals. That is, the introduction of laser-induced surface modifications enhanced the ion migration along the depth direction. Transmission electron microscopy showed that the crystallinity of diamond was better in the crystal subjected to high-temperature implantation. These results support the idea that femtosecond-laser-induced surface modifications can enhance dopant incorporation into diamond while preserving the diamond’s crystallinity.
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- 2022
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27. Long-term prognosis of patients with cancer-related genes detected in postoperative peritoneal washings obtained during curative gastrectomy
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Hiroya Iida, Tsuyoshi Yamaguchi, Masaji Tani, Tomoyuki Ueki, Miyuki Shimoji, Katsushi Takebayashi, Hirokazu Kodama, Sachiko Kaida, Toru Miyake, Satoshi Murata, Ken Ishikawa, Tomoharu Shimizu, Masatsugu Kojima, and Hiromitsu Maehira
- Subjects
Adult ,Male ,medicine.medical_specialty ,Peritoneal cancer ,medicine.medical_treatment ,Keratin-20 ,Fatty Acid-Binding Proteins ,Gastroenterology ,Disease-Free Survival ,03 medical and health sciences ,0302 clinical medicine ,Gastrectomy ,Stomach Neoplasms ,Laparotomy ,Internal medicine ,Gene duplication ,medicine ,Humans ,Peritoneal Lavage ,RNA, Messenger ,Peritoneal Neoplasms ,Aged ,Proportional Hazards Models ,Aged, 80 and over ,Mucin-2 ,business.industry ,Reverse Transcriptase Polymerase Chain Reaction ,Carcinoma ,General Medicine ,Middle Aged ,Curative gastrectomy ,Prognosis ,Carcinoembryonic Antigen ,Reverse transcription polymerase chain reaction ,Cancer related genes ,Oncology ,030220 oncology & carcinogenesis ,Cancer cell ,030211 gastroenterology & hepatology ,Surgery ,Female ,Trefoil Factor-1 ,business ,Transcriptome - Abstract
Cancer cells in intraoperative peritoneal washings (PW) indicate increased peritoneal recurrence. Detection of CEA or CK20 genes indicates poor prognosis. We assessed long-term prognosis of patients with amplification of cancer-related genes in PW obtained intraoperatively during curative gastric cancer surgery.PW was collected before and immediately after curative gastrectomy. CEA, CK20, TFF1, MUC2, and FABP1-mRNA were selected as marker genes for reverse transcription polymerase chain reaction. Peritoneal recurrence-free survival (PRFS) and overall survival (OS) after7-year follow-up were examined using the Kaplan-Meier method.Of 138 patients who underwent gastrectomy with negative cytological findings at laparotomy, 80 patients showed negative cancer-related gene amplification in preoperative PW. Fifty-eight patients were excluded due to positive gene amplification, which suggested presence of preoperative peritoneal cancer cells. The 80 patients had mRNA amplification in PW after surgery. Amplification of multiple and single cancer-related marker genes was observed in 38 and 21 patients; 21 cases had marker-negative results. Five-year PRFS was 69.1%, 95.2%, and 100% in multi-marker-positive, single marker-positive, and marker-negative cases, respectively. Multi-marker-positive patients had significantly worse PRFS than the other groups (p 0.05). Multivariate analysis in the Cox proportional hazards model identified multi-marker-positivity as an independent prognostic factor for PRFS (hazard ratio, 7.6; 95% confidence interval, 1.07-62.63; p = 0.046), and multi-marker-positive patients had significantly worse OS than other groups (p 0.01).Multi-marker cancer-related gene amplification in PW is associated with worse prognosis in PRFS and OS even after a long follow-up; PRFS can be stratified by the number of genes amplified.
- Published
- 2021
28. [A Case of Simultaneous Double Cancer with Gastric Metastasis of Breast Cancer and Lung Cancer]
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Takeru, Maekawa, Sachiko, Kaida, Ken, Ishikawa, Tsuyoshi, Yamaguchi, Katsushi, Takebayashi, Hiromitsu, Maehira, Toru, Miyake, Tomoyuki, Ueki, Hiroya, Iida, and Masaji, Tani
- Subjects
Lung Neoplasms ,Gastrectomy ,Stomach Neoplasms ,Humans ,Breast Neoplasms ,Female ,Carcinoma, Signet Ring Cell - Abstract
A 60s female with complaint of epigastric discomfort revealed 0-Ⅱb lesion in gastric fornix on upper gastrointestinal endoscopy and exhibited signet-ring cell carcinoma on histopathologic examination of biopsy specimens. A thoracoabdominal CT scan suggested tumors in right breast and left lung, and biopsy revealed invasive lobular carcinoma and primary lung adenocarcinoma, respectively. As results of multidisciplinary discussion of the treatment strategy for triple cancers, it was decided to perform robotic proximal gastrectomy, D1+ lymph node dissection, and esophagogastrostomy. The gastric lesion was diagnosed as gastric metastasis of breast cancer(T2N1M1, Stage Ⅳ)because immunohistochemical staining findings showed ER(+), GCDFP-15(+), and GATA-3(+). Two months later, she underwent the left upper lobectomy, and was diagnosed with lung acinar adenocarcinoma(pT2N0M0, pStage ⅠB). Six months after gastrectomy, she is currently on hormone therapy with aromatase inhibitors for breast cancer.
- Published
- 2021
29. Successful Laparoscopy-assisted Repair of a Rectovaginal Fistula after Low Anterior Resection for Rectal Cancer: A Report of Two Cases
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Hiroyuki Ohta, Kyozo Hashimoto, Tomoyuki Mizukuro, Byonggu An, Yumi Zen, Masatsugu Kojima, Tomoyuki Ueki, Toru Miyake, Yusuke Nishina, Yoshitaka Terada, Naomi Kitamura, Hiroya Akabori, Mitsuhiro Fujino, Tomoharu Shimizu, Masaji Tani, and Eiji Mekata
- Abstract
Background: A rectovaginal fistula (RVF) after low anterior resection for rectal cancer is troublesome and refractory. Although various surgical procedures have been previously described, no definitive procedure has shown satisfactory outcomes. We present two consecutive Japanese patients who underwent successful surgery for a RVF after low anterior resection. Case presentation: The patients were a 61-year-old woman and a 64-year-old woman. They were admitted to our hospital with a chief complaint of fecal discharge from the vagina after low anterior resection using the double-stapling technique for rectal cancer. They were diagnosed with RVF. Local surgical procedures, including diverting ileostomy, were unsuccessful in previous hospitals. Therefore, we performed laparoscopy-assisted repair of the RVF. In both the patients, laparoscopically robust pelvic adhesions were dissected, and the sigmoid colon was transected just before the RVF. Thereafter, in combination with a perineal approach, the rectum along with a previous anastomosis and fistula were completely removed. Surgeries were completed after vaginal repair, redo coloanal anastomosis, and interposition of the dissected connective tissue. In both the patients, the postoperative courses were uneventful. They have complained of neither recurrence of any RVF nor fecal incontinence 1 year and 10 months respectively after diverting stoma closure.Conclusions: A laparoscopy-assisted procedure with reanastomosis and interposition of the perineal connective tissue can be an effective treatment for an RVF after low anterior resection for rectal cancer.
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- 2020
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30. IgG4-related focal retroperitoneal fibrosis in ureter suggestive of colon cancer recurrence and resected laparoscopically: a case report
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Masaji Tani, Mitsuhiro Narita, Toru Miyake, Tomoharu Shimizu, Tomoyuki Ueki, Hiroya Iida, Masatsugu Kojima, and Sachiko Kaida
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Laparoscopic surgery ,medicine.medical_specialty ,Colorectal cancer ,medicine.medical_treatment ,lcsh:Surgery ,030232 urology & nephrology ,Case Report ,Retroperitoneal fibrosis ,03 medical and health sciences ,0302 clinical medicine ,Ureter ,parasitic diseases ,Biopsy ,medicine ,IgG4-related disease ,Fluorodeoxyglucose ,medicine.diagnostic_test ,business.industry ,fungi ,lcsh:RD1-811 ,IgG4-related focal retroperitoneal fibrosis ,medicine.disease ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Radiology ,Differential diagnosis ,medicine.symptom ,business ,medicine.drug - Abstract
Background Immunoglobulin G4-related disease (IgG4-RD) is a novel disease concept of unknown cause that is characterized by abundant infiltration of IgG4-positive cells, mass-forming lesions, and elevated serum IgG4 levels. The infiltration of IgG4-positive plasma cells and lymphocytes causes swelling, inflammation, fibrosis, and obliterative phlebitis in multiple organs. On the other hand, IgG4-RD occurring in the ureters has rarely been reported. To our knowledge, this is the first report of laparoscopic partial ureteral resection for IgG4-related focal retroperitoneal fibrosis in a ureter with suspected colon cancer recurrence. Case presentation A 72-year-old man with a history of sigmoid colon cancer visited Shiga University of Medical Science Hospital for regular follow-up in December 2019. Enhanced abdominal computed tomography revealed a mass involving the left ureter. Furthermore, fluorine-18 fluorodeoxyglucose positron emission tomography showed significant accumulation of fluorodeoxyglucose uptake in the same region. Due to the possibility of colon cancer recurrence, a laparoscopic excisional biopsy with partial ureteral resection was performed. Histologically, IgG4-positive plasma cell infiltration exceeding 10 cells per high-power field and a high ratio of IgG4-positive/IgG-positive cells exceeding 40% were observed. The postoperative serum IgG4 level was 384 mg/dL. With the application of these findings to the diagnostic algorithm in the comprehensive diagnostic criteria for IgG4-RD, the mass-forming lesion was diagnosed as definitive IgG4-related focal retroperitoneal fibrosis. Conclusions IgG4-RD should be considered in the differential diagnosis of retroperitoneal lesions. Moreover, laparoscopic surgery may be useful for making the diagnosis in difficult-to-biopsy cases.
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- 2020
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31. Formation of ohmic Ni electrodes on femtosecond laser-modified 4H–SiC surface
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Yuki Fuchikami, Tatsuya Okada, Kazuki Mimura, Tomoyuki Ueki, Takuro Tomita, and Hiromu Hisazawa
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010302 applied physics ,Diffraction ,Materials science ,Annealing (metallurgy) ,Analytical chemistry ,Schottky diode ,02 engineering and technology ,General Chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Crystal ,0103 physical sciences ,Femtosecond ,Electrode ,General Materials Science ,Selected area diffraction ,0210 nano-technology ,Ohmic contact - Abstract
The objective of the present study was to investigate the effects of femtosecond laser-induced modifications on the current–voltage (I–V) characteristics between Ni electrodes deposited on laser-irradiated areas on n-type 4H–SiC crystals. We investigated the I–V characteristics and their changes from low-temperature annealing at 400 °C or 500 °C. The I–V characteristics were not the typical Schottky ones, but nonlinear and without a rectifying voltage range even before annealing, and they approached linear with longer annealing durations. An almost linear (i.e., ohmic) I–V curve was obtained for the sample annealed at 500 °C for 18 min. A selected area diffraction pattern taken from the cross section of a laser-irradiated line in the annealed sample was composed of diffraction spots from pure Ni and δ-Ni2Si grains. The coarse-grained Ni2Si phase had an orientation relationship with the SiC crystal, i.e., SiC(0001)//Ni2Si(100) and SiC $$(1\stackrel{-}{1}00)$$ //Ni2Si(013).
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- 2020
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32. Report of Two Cases of Colon Cancer Diagnosed after Onset of Infective Endocarditis
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Toru Miyake, Tomoyuki Ueki, Hiromichi Sonoda, Hiroya Akabori, Yumi Zen, Hiroyuki Ohta, Tomoharu Shimizu, Eiji Mekata, Masaji Tani, and Masatsugu Kojima
- Subjects
medicine.medical_specialty ,business.industry ,Colorectal cancer ,Internal medicine ,Infective endocarditis ,medicine ,General Earth and Planetary Sciences ,medicine.disease ,business ,Gastroenterology ,General Environmental Science - Published
- 2019
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33. Grain-Boundary Sliding and Its Accommodation at Triple Junctions in Aluminum and Copper Tricrystals
- Author
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Akihiro Iwasaki, Jun Miyaji, Hiromu Hisazawa, Tomoyuki Ueki, Tatsuya Okada, Masaki Shisawa, and Shota Amimoto
- Subjects
Materials science ,Creep ,chemistry ,Mechanics of Materials ,Aluminium ,Mechanical Engineering ,Triple junction ,chemistry.chemical_element ,General Materials Science ,Composite material ,Condensed Matter Physics ,Copper ,Grain Boundary Sliding - Published
- 2019
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34. [Study of Eight Cases of Retroperitoneal Liposarcoma]
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Takashi, Matsunaga, Tsuyoshi, Yamaguchi, Sachiko, Kaida, Katsushi, Takebayashi, Satoshi, Murata, Tomoharu, Shimizu, Hiromichi, Sonoda, Toru, Miyake, Tomoyuki, Ueki, Hiroya, Iida, Naomi, Kitamura, Hiromitsu, Maehira, Akiko, Matsubara, Ryoji, Kushima, and Masaji, Tani
- Subjects
Humans ,Liposarcoma ,Retroperitoneal Neoplasms ,Neoplasm Recurrence, Local ,Prognosis - Abstract
Retroperitoneal liposarcoma is a relatively rare disease, with a high recurrence rate and poor prognosis. We encountered 8 patients with retroperitoneal liposarcoma who underwent surgery in Shiga University of Medical Science Hospital. We often encounter elderly male patients without symptoms. Of the 8 patients, 6 received extensive resection that included the surrounding organs or tissues; however, 3 patients demonstrated positive surgical margins, which resulted in liposarcoma recurrence. Despite the additional resection in the 3 recurrent cases, all the patients had a tumor relapse. One patient with an unresectable tumor received chemotherapy. The other patients received surgical treatment 3 times. One patient developed an unresectable relapse after receiving chemotherapy. Another patient attained long-term survival by adjuvant chemoradiotherapy combined with 3 surgeries. Aggressive surgical resection to achieve a negative surgical margin and careful postoperative follow-up seem important for the treatment of retroperitoneal liposarcoma. This study suggests that postoperative adjuvant therapy may contribute to the improvement of prognosis. Further findings must be accumulated to clarify the significance of postoperative adjuvant therapies in the future.
- Published
- 2020
35. A Complete Response to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Squamous Cell Carcinoma: Two Case Reports
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Hiromichi Sonoda, Masaji Tani, Tomoharu Shimizu, Suzuko Moritani, Jun-ichi Aburaki, Tomoyuki Ueki, Hiroyuki Ohta, Junpei Yonemaru, and Toru Miyake
- Subjects
Oncology ,medicine.medical_specialty ,business.industry ,Internal medicine ,Gastroenterology ,medicine ,Locally advanced ,Surgery ,Rectal Squamous Cell Carcinoma ,business ,Complete response ,Neoadjuvant chemoradiotherapy - Published
- 2018
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36. High temperature degradation mechanism of a red phosphor, CaAlSiN3:Eu for solid-state lighting.
- Author
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Masatsugu Oishi, Shohei Shiomi, Takashi Yamamoto, Tomoyuki Ueki, Yoichiro Kai, Chichibu, Shigefusa F., Aiko Takatori, and Kazunobu Kojima
- Subjects
SOLID state chemistry ,PHOSPHORS ,HIGH temperatures ,THERMAL properties ,EXCITATION spectrum - Abstract
Thermal properties of a red phosphor CaAlSiN
3 :Eu (CASN) at elevated temperatures were evaluated. A heat treatment at 800°C degraded the photoluminescence property of CASN and caused irreversible changes in both the excitation and emission intensities. The heat treatment in air simultaneously decreased the N elements and increased the O elements. Consequently, the Eu2+ luminescence center was oxidized and CASN lost its photoluminescence property. Although the crystal structure of CASN host was stable even after the heat treatments, the local structure change around the Eu2+ ions is the origin of the thermal degradation of CASN. We found that the heat treatment in N2 atmosphere suppresses the thermal degradation. This is due to the suppression of N evolutions and the incorporation of O elements, which sustains the optically active Eu2+ state. [ABSTRACT FROM AUTHOR]- Published
- 2017
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37. In vivoantitumor function of tumor antigen-specific CTLs generated in the presence of OX40 co-stimulationin vitro
- Author
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Toru Miyake, Tomoyuki Ueki, Naomi Kitamura, Ngoc Pham Minh, Hirokazu Kodama, Satoshi Murata, Masatsugu Kojima, Katsushi Takebayashi, Eiji Mekata, and Masaji Tani
- Subjects
0301 basic medicine ,Cancer Research ,Adoptive cell transfer ,biology ,Effector ,Chemistry ,medicine.medical_treatment ,Immunotherapy ,Major histocompatibility complex ,Tumor antigen ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Oncology ,Cancer immunotherapy ,In vivo ,030220 oncology & carcinogenesis ,medicine ,biology.protein ,Cancer research ,CD8 - Abstract
Adoptive cell transfer (ACT) is an emerging and promising cancer immunotherapy that has been improved through various approaches. Here, we described the distinctive characteristics and functions of tumor Ag-specific effector CD8+ T-cells, co-cultured with a tumor-specific peptide and a stimulatory anti-OX40 antibody, before being used for ACT therapy in tumor-bearing mouse recipients. Splenic T-cells were obtained from wild-type FVB/N mice that had been injected with a HER2/neu (neu)-expressing tumor and a neu-vaccine. The cells were then incubated for 7 days in vitro with a major histocompatibility complex (MHC) class I peptide derived from neu, in the presence or absence of an agonistic anti-OX40 monoclonal antibody, before CD8+ T cells were isolated for use in ACT therapy. The proliferative ability of OX40-driven tumor Ag-specific effector CD8+ T-cells in vitro was less than that of non-OX40-driven tumor Ag-specific effector CD8+ T-cells, but they expressed significantly more early T-cell differentiation markers, such as CD27, CD62L and CCR7, and significantly higher levels of Bcl-2, an anti-apoptotic protein. These OX40-driven tumor Ag-specific effector CD8+ T-cells, when transferred into tumor-bearing recipients, demonstrated potent proliferation capability and successfully eradicated the established tumor. In addition, these cells exhibited long-term antitumor function, and appeared to be established as memory T-cells. Our findings suggest a possible in vitro approach for improving the efficacy of ACT, which is simple, requires only a small amount of modulator, and can potentially avoid several toxicities associated with co-stimulation in vivo.
- Published
- 2018
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38. Laparoscopic Surgery for Ileoceacal Abscess due to Crohn’s Disease Occurred to the Patient with Severe Motor and Intellectual Disabilities
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Toru Miyake, Yoshitaka Terada, Hiromichi Sonoda, Tomoharu Shimizu, Tomoyuki Ueki, and Masaji Tani
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Laparoscopic surgery ,medicine.medical_specialty ,Crohn's disease ,business.industry ,General surgery ,medicine.medical_treatment ,medicine ,medicine.disease ,Abscess ,business - Published
- 2017
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39. A Case of Endometriosis in Rectosigmoid Treated by Laparoscopic Surgery
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Katsushi Takebayashi, Hiroya Iida, Tsuyoshi Yamaguchi, Masaji Tani, Toru Miyake, Hiromichi Sonoda, Tomoharu Shimizu, Tomoyuki Ueki, Daiji Ikuta, and Sachiko Kaida
- Subjects
Laparoscopic surgery ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Endometriosis ,Medicine ,business ,medicine.disease ,Surgery - Published
- 2017
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40. [A Surgically Resected Case of Retroperitoneal Liposarcoma with Metastasis]
- Author
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Yoshitaka, Terada, Sachiko, Kaida, Tsuyoshi, Yamaguchi, Katsushi, Takebayashi, Haruki, Mori, Tomoharu, Shimizu, Hiromichi, Sonoda, Hiroya, Iida, Toru, Miyake, Tomoyuki, Ueki, Naomi, Kitamura, Hiromitsu, Maehira, Soichiro, Tani, and Masaji, Tani
- Subjects
Aged, 80 and over ,Male ,Humans ,Liposarcoma ,Retroperitoneal Neoplasms ,Prognosis ,Kidney Neoplasms - Abstract
An 80s man presenting with general malaise and anorexia was referred for treatment of abdominal tumor. Abdominal contrast-enhanced CT revealed a tumor in the left renal cavity. The inside of the tumor coexisted with a fat component and a solid component having a contrast effect. In addition, 2 solid tumors were found to be in contact with the stomach, away from the primary lesion. Based on these findings, retroperitoneal liposarcoma with intraperitoneal metastases was diagnosed. The patient underwent excision of the retroperitoneal tumor and local gastrectomy. The size of the main tumor was 21×18 cm, and the weight was 2.0 kg. Histopathology of the resected specimen showed dedifferentiated liposarcoma and its metastases. The resected margin of the excised tumor was negative. Liposarcoma has a high local recurrence rate, and the status of a resected margin of the tumor is an important factor for prognosis. Here, we report a case of dedifferentiated liposarcoma with metastatic lesions that could be completely resected.
- Published
- 2019
41. [Prognosis of Patients after Palliative Stoma Creation]
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Soichiro, Tani, Toru, Miyake, Tomoharu, Shimizu, Hiromichi, Sonoda, Tomoyuki, Ueki, Sachiko, Kaida, Naomi, Kitamura, Hiroya, Iida, Tsuyoshi, Yamaguchi, and Masaji, Tani
- Subjects
Palliative Care ,Humans ,Surgical Stomas ,Colorectal Neoplasms ,Prognosis ,Intestinal Obstruction ,Aged ,Retrospective Studies - Abstract
We evaluated the effectiveness of palliative stomas created to resolve symptoms of bowel obstruction.We retrospectively evaluated patient characteristics and outcomes in 16 cases of palliative enterostomy performed to resolve malignant bowel obstruction.The median age of the patients was 64 years, and the most common original cancer was colorectal cancer(11 cases, 69%). Oral intake was recovered in 15 patients after the surgery(94%), and the colorectal obstruction scoring system(CROSS)score improved from 2 to 4. Postoperative complications(Clavien-Dindo grade Ⅱ or higher)were observed in 8 cases(50%), in which serum albumin levels were less than 3.5 g/dL(p=0.077), resulting in longer hospital stays(p=0.041). The median overall survival time was 107 days, and longer survival time was achieved in patients aged younger than 70 years, with CA19-9 levels C37.7 U/mL and postoperative CROSS score of 4, who were administered postoperative chemotherapy. The chemotherapy was feasible after surgery when CROSS scores improved to 4(p=0.019).Palliative stomas contributed to the improvement in oral intake of patients with terminal cancer. This improvement may allow patients to receive postoperative chemotherapy, which leads to longer survival times.
- Published
- 2019
42. Electronic state analysis of Li2RuO3 positive electrode for lithium ion secondary battery
- Author
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Masatsugu Oishi, Hirona Yamagishi, Ryoshi Imura, Iwao Watanabe, Tomoyuki Ueki, and Keiji Shimoda
- Subjects
Battery (electricity) ,X-ray absorption spectroscopy ,Materials science ,Absorption spectroscopy ,XAS ,Analytical chemistry ,Oxide ,chemistry.chemical_element ,Statistical and Nonlinear Physics ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,O anion redox reaction ,01 natural sciences ,0104 chemical sciences ,Lithium ion secondary battery ,chemistry.chemical_compound ,X-ray photoelectron spectroscopy ,chemistry ,Transition metal ,Electrode ,XPS ,Lithium ,0210 nano-technology - Abstract
An investigation was made on the electronic structure of 4d transition metal layered oxide material of Li2RuO3 using X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The intensity of O [Formula: see text] pre-edge peak increased for Li ion extracted samples, suggesting increased ligand holes. The Ru 3d XPS spectrum suggested the variation of local structure around Ru ions by extraction of Li ions. We conclude that the delithiation from Li2RuO3 is charge compensated by O anions, and that the creation of the ligand holes reorganizes electronic structures composed of highly hybridized Ru 4d and O 2p orbitals.
- Published
- 2020
43. [A Case of Combined Treatment Approach of Endoscopic Submucosal Dissection and Transanal Minimally Invasive Surgery for Radiation Induced Rectal Cancer]
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Toru, Miyake, Hiromichi, Sonoda, Tomoharu, Shimizu, Tomoyuki, Ueki, Haruki, Mori, Katsushi, Takebayashi, Sachiko, Kaida, Tsuyoshi, Yamaguchi, Hiroya, Iida, Hiromitsu, Ban, and Masaji, Tani
- Subjects
Male ,Neoplasms, Radiation-Induced ,Endoscopic Mucosal Resection ,Humans ,Colonoscopy ,Intestinal Mucosa ,Aged - Abstract
It is hard to determine treatment strategy for radiation induced carcinoma, because radiation cause fibrosis to adjacent organ.The patient was in the 70's, who underwent 70 Gy radiation therapy for prostate cancer 5 years ago.He visited hospital because of fecal occult blood.Endoscopic examination revealed laterally spreading tumor(LST)in rectal front wall, and he referred to our hospital in purpose of endoscopic submucosal dissection(ESD).We performed ESD for LST, following transanal minimally invasive surgery to suture mucosal defect.He discharged out hospital 9 days after operation without any adverse event except anal pain.Suturing of mucosal defect after ESD might be potent to prevent postoperative complications in radiation induced rectal cancer.
- Published
- 2018
44. [A Case of Gastric Cancer Underwent Two-Stage Gastrectomy after Chemotherapy-Induced Perforation]
- Author
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Yumi, Zen, Sachiko, Kaida, Katsushi, Takebayashi, Tsuyoshi, Yamaguchi, Satoshi, Murata, Yoshitaka, Terada, Tomoyuki, Ueki, Toru, Miyake, Hiroya, Iida, Hiroya, Akabori, Naomi, Kitamura, Hiromichi, Sonoda, Tomoharu, Shimizu, Shigeyuki, Naka, and Masaji, Tani
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Male ,Drug Combinations ,Oxonic Acid ,Gastrectomy ,Stomach Neoplasms ,Antineoplastic Combined Chemotherapy Protocols ,Stomach Diseases ,Humans ,Cisplatin ,Aged ,Tegafur - Abstract
A 70's man presenting with a chief complaint of stomachache was found to have advanced gastric cancer with a deep ulcer and some lymph-node metastases. We decided performing a curative operation after 2 courses of S-1 plus cisplatin. On the first course day 13 of chemotherapy, he complained of severe epigastralgia, and we diagnosed as generalized peritonitis due to perforation of gastric cancer. We performed an urgent laparoscopic operation, which made perforation simple closure and omentopexy. Curative distal gastrectomy with D2 lymph node dissection was successfully performed on postoperative day 16.
- Published
- 2018
45. [A Case of Synchronous Quadruple Cancers Treated with Neoadjuvant Chemotherapy Followed by Surgery]
- Author
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Keiji, Muramoto, Toru, Miyake, Tomoharu, Shimizu, Hiromichi, Sonoda, Tomoyuki, Ueki, Yoshitaka, Terada, Haruki, Mori, Hiromitsu, Maehira, Katsushi, Takebayashi, Sachiko, Kaida, Hiroya, Iida, Tsuyoshi, Yamaguchi, and Masaji, Tani
- Subjects
Male ,Neoplasms, Multiple Primary ,Lung Neoplasms ,Stomach Neoplasms ,Antineoplastic Combined Chemotherapy Protocols ,Colonic Neoplasms ,Humans ,Prostatic Neoplasms ,Neoadjuvant Therapy - Abstract
The patient is male in his 60's. He underwent endoscopic examination for anemia, which was found during screening of high PSA value. Endoscopic examination revealed a gastric cancer and 3 colorectal cancers. Histological results from biopsy was HER2 positive poorly differentiated adenocarcinoma in gastric tumor and moderately differentiated adenocarcinoma in colorectal tumor. Chest CT showed a pulmonary nodule in the middle right lung. Histological diagnosis was TTF-1 positive adenocarcinoma, meaning primary lung cancer. Histological examination of prostate biopsy also showed adenocarcinoma. Clinical stages were Stage III B of gastric cancer, Stage III a of colorectal cancer, Stage I A of lung cancer and Stage I of prostate cancer. Neoadjuvant chemotherapy for gastric cancer was performed because gastric cancer with advanced clinical stage was regard as a prognostic factor. Neoadjuvant chemotherapy shrinked gastric and colorectal cancers, so we performed distal gastrectomy for gastric cancer and super low anterior resection for colorectal cancer. Patient was discharged 22 days after operation without any serious adverse events. Hormonal treatment for prostate cancer and radiation therapy for lung cancer were performed. Now this patient is alive without any recurrence.
- Published
- 2018
46. [A Case of Small Intestinal GIST with Long-Term Survival after Tumor Resection for Repeated Peritoneal Recurrence]
- Author
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Yoshitaka, Terada, Hiromichi, Sonoda, Toru, Miyake, Tomoharu, Shimizu, Tomoyuki, Ueki, Katsushi, Takebayashi, Sachiko, Kaida, Tsuyoshi, Yamaguchi, Naomi, Kitamura, Hiroya, Iida, Hiroya, Akabori, Tsuyoshi, Mori, and Masaji, Tani
- Subjects
Time Factors ,Gastrointestinal Stromal Tumors ,Recurrence ,Intestinal Neoplasms ,Intestine, Small ,Imatinib Mesylate ,Humans ,Antineoplastic Agents ,Female ,Combined Modality Therapy ,Peritoneal Neoplasms ,Aged - Abstract
A 70-year-old woman presenting with abdominal pain was admitted to our hospital. Abdominal contrast CT revealed a small intestine tumor of 10 cm with active bleeding and performed partial resection of the small intestine including tumor. Pathological findings were high risk GIST of the small intestine because of spindle cells and c-kit positive. Imatinib 400mg/day as adjuvant chemotherapy was administered. However administration was stopped for 15 days because of the Grade 4 erythema multiforme. Recurrence of peritoneal dissemination was observed in 2 years after surgery and tumor resection was performed, but complete resection was difficult. Within 5 years after surgery, tumor resection was performed on a total of 5 times peritoneal disseminative recurrences, and it was possible to avoid the appearance of symptoms due to tumor augmentation.
- Published
- 2018
47. [Clinical Evaluation of Perforated Gastric Cancer Cases]
- Author
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Sachiko, Kaida, Tsuyoshi, Yamaguchi, Reiko, Otake, Katsushi, Takebayashi, Tomoyuki, Ueki, Toru, Miyake, Hiroya, Iida, Hiromichi, Sonoda, Tomoharu, Shimizu, and Masaji, Tani
- Subjects
Adult ,Aged, 80 and over ,Male ,Gastrectomy ,Stomach Neoplasms ,Stomach Diseases ,Humans ,Female ,Middle Aged ,Prognosis ,Aged - Abstract
Perforated gastric cancer is relatively rare disease. Between 2006 and 2016, we treated 8 cases with perforative gastric cancer. These cases accounted for 15%of the 53 cases with the upper gastrointestinal tract perforated cases. The median age of perforated gastric cancer case was 66(37-80)years, which was significantly higher than that of perforated benign upper gastrointestinal ulcer(55, 12-97 years)(p=0.033). These patients were divided into 2 groups; 3 cases who died up to 3 months as poor prognosis group and 5 cases who survived more than 4 months as good prognosis group. Poor prognosis group tended to be higher Glasgow prognostic score(GPS)(p=0.05)and lower serum albumin level(p=0.05)than good prognosis group. GPS and serum albumin level may predict the prognosis of perforated gastric cancer patients.
- Published
- 2018
48. Influence of alkali treatment on internal microstructure and tensile properties of abaca fibers
- Author
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Ming Cai, Geoffrey I. N. Waterhouse, Yan Li, Antonio Norio Nakagaito, Masahiro Katoh, Hitoshi Takagi, and Tomoyuki Ueki
- Subjects
Materials science ,Scanning electron microscope ,Young's modulus ,Microstructure ,symbols.namesake ,chemistry.chemical_compound ,chemistry ,Sodium hydroxide ,Ultimate tensile strength ,Polymer chemistry ,symbols ,medicine ,Hemicellulose ,Cellulose ,Swelling ,medicine.symptom ,Composite material ,Agronomy and Crop Science - Abstract
The objective of this study is to investigate the effect of alkali treatment on the internal microstructure and tensile properties of abaca fibers. The abaca fibers were immersed in aqueous solutions of NaOH (5, 10, or 15 wt%) for 30 min, rinsed and dried. The fibers were subsequently characterized by scanning electron microscopy, X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), and tensile strength tests. The lumen is a hollow region in each elementary fiber of the abaca fiber bundles. It was found that the lumen of the abaca fibers completely collapsed after 10 and 15 wt% NaOH treatment, due to swelling of the fibers. The fibers also became twisted after these alkali treatments. It was found that cellulose I in abaca fibers was partially transformed to cellulose II after 15 wt% NaOH treatment, as evidenced by XRD measurements. FT-IR analysis indicated that the alkali treatment led to a gradual removal of binding materials; such as hemicelluloses and lignin, from the abaca fibers, resulting in the separation of abaca fiber bundles into individual elementary fibers. The tensile strength of alkali-treated abaca fibers did not vary with alkali concentration. The Young’s modulus of the abaca fibers treated with 5 wt% NaOH solution increased by 41%, whereas those treated with 10 and 15 wt% NaOH solution decreased by 24 and 29%, respectively. A non-linear behavior was observed in the stress–strain curves of the abaca fibers after 10 and 15 wt% alkali treatment, which could be attributable to the twisting of the fibers.
- Published
- 2015
- Full Text
- View/download PDF
49. Creep Fracture of Aluminum and Copper Tricrystals Having ©110ª-Tilt 3, 3, 9 Grain Boundaries.
- Author
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Tatsuya Okada, Hiromu Hisazawa, Akihiro Iwasaki, Katsuya Kawaguchi, Hiroki Morimoto, Kazuki Nakao, Tomoyuki Ueki, and Takuro Tomita
- Subjects
CRYSTAL grain boundaries ,ALUMINUM ,COPPER ,TENSILE tests ,STRESS concentration - Abstract
The major objective of the present study was to investigate the effect of the constraint of grain-boundary sliding and its accommodation at triple junctions on the creep fracture of tricrystals. Tricrystals of pure aluminum and copper having ©110ª-tilt 3, 3, 9 boundaries were grown by the Bridgman method. Creep tests were carried out for tensile specimens in which the 9 boundary made an angle of 45° with the tensile axis at temperatures above 0.80 TM, where TM stands for the melting temperature on the absolute temperature scale. In both aluminum and copper tricrystals, dominant grain-boundary sliding occurred along the 9 boundary. The aluminum tricrystal fractured along a plane across grains, far separated from the triple junction. In contrast, the copper tricrystal fractured via a complete separation along the 9 boundary followed by a tear-off of the remaining portion. This difference is accounted for by the different local deformation behaviors around the triple junctions to release the stress concentration induced by the constraint of 9 sliding, e.g., grain-boundary sliding along the 3 boundary in aluminum and crack formation along the 9 boundary in copper. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
50. Bonding mechanism of lead-free solder and glass plate by ultrasonic assisted soldering method
- Author
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Toshio Wakabayashi, Kazushige Tokiyasu, Shuji Kira, Daisuke Yonekura, and Tomoyuki Ueki
- Subjects
Materials science ,Chemical bond ,X-ray photoelectron spectroscopy ,Scanning electron microscope ,Transmission electron microscopy ,Anodic bonding ,Soldering ,Intermetallic ,Wetting ,Composite material - Abstract
Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the bonding mechanism of lead (Pb)-free solder to glass by ultrasonic assisted soldering. In addition, the effects of ultrasonication, the elements and the oxygen concentration in the solder on the bonding behavior were also investigated. Ultrasonication during the soldering process led to an improvement of the wettability and accelerated the bonding between the lead-free solder and glass. No intermetallic compound layer was identified around the solder and glass interface from SEM and TEM observations. Chemical shifts of O 1s, Zn 2p and Si 2p were observed at the interface by X-ray photoelectron spectroscopy (XPS) analysis, which is attributed to chemical bonding between the glass and a solder component element. In particular, zinc was identified as an important element to form the bond between the glass and solder. The chemical bonding is accelerated by acoustic cavitation due to the ultrasonication.
- Published
- 2015
- Full Text
- View/download PDF
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