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Dive into the research topics where Nobutaka Hatanaka is active.

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Featured researches published by Nobutaka Hatanaka.


Transplantation | 1993

ATTENUATION OF WARM ISCHEMIC INJURY OF RAT LUNG BY INFLATION WITH ROOM AIR-ASSESSMENT OF CELLULAR COMPONENTS AND THE SURFACTANT IN THE BRONCHOALVEOLAR LAVAGE FLUID IN RELATION TO CHANGES IN CELLULAR ADENOSINE TRIPHOSPHATE

Akinori Akashi; Kazuya Nakahara; Wataru Kamiike; Akihide Matsumura; Nobutaka Hatanaka; Yasunaru Kawashima; Yukuo Yoshida; Kunio Tagawa

Studies were made on the effects in rat lungs of aerobic and anaerobic conditions on the intracellular levels of adenosine triphosphate and its related metabolites, the releases of intracellular enzymes, and the secretion of pulmonary surfactant. After warm ischemia for 120 min, the ATP content of lungs inflated with air was significantly higher (8.0±1.2 μmol/g dry weight) than those of deflated lungs and lungs inflated with nitrogen (0.8±0.7 μmol/g dry weight and 2.0±0.7 μmol/g dry weight, respectively; P<0.001). The amounts of intracellular enzymes, such as lactate dehydrogenase, cyto-solic and mitochondrial aspartate aminotransferase, and protein in the bronchoalveolar lavage fluid (BALF) of air-inflated lungs were significantly less than those in BALFs of deflated and nitrogen-inflated lungs (P<0.001). The BALF-contents of dipalmitoyl phosphatidylcholine (DPPC), the main component of alveolar surfactant of aerobic and anaerobic ischemic lung were, however, similar. During 120-min warm ischemia after lavage, air-inflated lungs secreted significantly more DPPC into the alveolar space than nitrogen-inflated lungs did (P<0.001). We conclude that cell membranes in the lungs are damaged under anaerobic conditions, but that inflation of ischemic lungs with air is effective for protecting them from cell injury and for maintaining the intracellular level of ATP and the ability of the cells to secrete pulmonary surfactant.


Transplantation | 1994

Enzyme release from mitochondria during reoxygenation of rat liver

Shigeomi Shimizu; Wataru Kamiike; Nobutaka Hatanaka; Motonobu Nishimura; Masahiko Miyata; Toru Inoue; Yukuo Yoshida; Kunio Tagawa; Hikaru Matsuda

Reoxygenation-induced release of mitochondrial aspartate aminotransferase (mAST) into the cytosol was studied using perfused rat liver. As the absolute activity of mAST in the perfusate did not indicate the degree of mitochondrial enzyme release, the following 3 methods were applied: measurement of the mAST to total AST ratio in the efferent perfusate, the digitonin infusion method, and measurement of mAST activity in the cytosolic compartment isolated from perfused livers. The results by all 3 methods were consistent and showed that mitochondrial injury occurs on reoxygenation. The mitochondrial Ca2+ content was proportional to the extent of mAST release during reoxygenation, indicating involvement of Ca2+ in the enzyme release. CsA, a potent inhibitor of Ca(2+)-induced increase in permeability of the mitochondrial membrane, completely prevented mAST release on reoxygenation. We conclude that during reoxygenation of hypoxic liver, mAST leaks into the cytosol in a Ca(2+)-dependent, CsA-sensitive manner.


Biochimica et Biophysica Acta | 1991

Protection of cellular and mitochondrial functions against anoxic damage by fructose in perfused liver

Hironao Okabe; Kazuhei Kurosawa; Nobutaka Hatanaka; Junichi Yoshitake; Kunio Tagawa

In anoxic perfused liver, conversion of fructose to lactate was greatly increased to about 3 mumol/min per g liver. This increase in lactate implied that the same amount of ATP was also produced. The rate of metabolism of glucose was less than 10% of that of fructose, as judged by rate of production of lactate. In anoxic liver perfused with fructose, the ATP levels of both the tissue and mitochondria remained high, despite lack of oxygen, thus preventing enzyme leakage and preserving processes requiring ATP, such as bile excretion and urea formation. The mitochondrial oxidative phosphorylation capacity of anoxic liver perfused with fructose was also unimpaired. Spectral analysis of light transmitted through the liver revealed that the mitochondrial electron transfer system was in the completely reduced state during anoxia, indicating that the mitochondria were incapable of synthesizing ATP. These results suggest that fructose metabolism during anoxia resulted in sufficient production of ATP for maintaining the physiological functions of the cells and the oxidative phosphorylation capacity of their mitochondria.


Surgery Today | 1993

Radical resection of primary malignant melanoma of the gallbladder with multiple metastases : report of a case

Nobutaka Hatanaka; Masahiko Miyata; Wataru Kamiike; Kenzo Okumura; Tsukuru Hashimoto; Tokio Yamaguchi; Yoshinobu Kishino; Masami Sakurai; Hikaru Matsuda

We present herein an usual case of primary malignant melanoma of the gallbladder in a 51-year-old man in whom an exploratory laparotomy for melena revealed six malignant melanoma lesions located in the gallbladder, main pancreatic duct, stomach, duodenum, jejunum, and a mesenteric lymph node. Total pancreatectomy was performed and histologically, junctional activity was seen only in the gall-bladder, suggesting that this was the primary site. No melanotic lesions were found on the skin or eyes. The metastases to the main pancreatic duct and gastrointestinal tract appeared likely to have occurred as a consequence of the mucosal dissemination of the tumor cells shed into the bile. The post-operative course was uneventful and combined chemotherapy was administered for 16 months. No new metastatic lesions were found until 21 months postoperatively, when metastases were detected in the brain and thoracic spinal cord. These metastatic tumors were removed surgically, but the patient died from cerebral disturbance 26 months after the initial operation. Thus, we consider that aggressive surgical therapy was effective for extending the survival time and improving the quality of life of this patient.


Gastroenterology | 1996

Improvement of rat liver graft function by insulin administration to donor.

Yoshikazu Morimoto; Wataru Kamiike; Toshirou Nishida; Nobutaka Hatanaka; Shigeomi Shimizu; Tai–Ping Huang; Eisaku Hamada; Yasuo Uchiyama; Yukuo Yoshida; Eisuke Furuya; Hikaru Matsuda

BACKGROUND & AIMS The nutritional status of a donor is considered to be an important factor affecting organ viability. The purpose of the present study was to examine hepatic energy status in connection with posttransplantation liver function. METHODS The following five groups of donor rat livers were prepared and stored in University of Wisconsin solution at 4 degrees C: fasted group, rats fasted for 24 hours; fed group, rats provided standard laboratory chow; fed plus insulin group, fed rats treated with insulin before harvest; fasted plus insulin group, fasted rats treated with insulin before harvest; and fed plus glucagon group, fed rats pretreated with glucagon. RESULTS Hepatic levels of adenosine triphosphate and total adenine nucleotides were maintained in the decreasing order of the fed plus insulin, fed, fasted plus insulin, fasted, and fed plus glucagon groups during preservation. Lactate production rate and fructose 2,6-bisphosphate level increased in the order of the fed plus insulin, fed, fed plus glucagon, fasted, and fasted plus insulin groups. Liver function after transplantation evaluated by the bile flow rate and enzyme leakage was well restored in the fed plus insulin group. CONCLUSIONS Insulin administration to nutritionally well-supported livers before harvest improved energy metabolism during preservation and liver function after transplantation.


Transplantation | 1994

Beneficial effects of cyclosporine on reoxygenation injury in hypoxic rat liver.

Shigeomi Shimizu; Wataru Kamiike; Nobutaka Hatanaka; Masahiko Miyata; Toru Inoue; Yukuo Yoshida; Kunio Tagawa; Hikaru Matsuda

The effect of CsA on hypoxia-reoxygenation injury was studied in perfused rat livers. CsA did not attenuate hypoxic injury, as assessed by the release of lactate dehydrogenase and mitochondrial aspartate aminotransferase. During reoxygenation, the release of lactate dehydrogenase was also not affected by CsA. However, the release of mitochondrial aspartate aminotransferase into the cytosol, which indicates mitochondrial injury, was significantly reduced by CsA. The effect of CsA on mitochondrial function during hypoxia-reoxygenation was also investigated. CsA administration increased both the respiratory control ratio and the adenine nucleotide content after reoxygenation in both isolated mitochondria and perfused livers. In addition, glucose production by perfused livers after reoxygenation was increased by CsA. We conclude that the beneficial effect of CsA on hypoxiareoxygenation injury may be partly due to protection of the mitochondria against reoxygenation injury.


International Surgery | 2012

Gastric neuroendocrine tumors in our institutions according to the WHO 2010 classification.

Shunji Endo; Tsutomu Dousei; Yukinobu Yoshikawa; Nobutaka Hatanaka; Kiyomi Taniyama; Amane Yamauchi; Wataru Kamiike; Junichi Nishijima

In 2010, World Health Organization classified gastric neuroendocrine tumor (NET) as follows: NET grade (G) 1, NET G2, neuroendocrine carcinoma (NEC). We reviewed 22 gastric NETs that were encountered in our institutions. Nine, 6, and 4 were NET G1, G2, and NEC, respectively. We also encountered 3 NET G3. NET G1 was treated with observation in 2 patients, endoscopic mucosal resection (EMR) in 3, and gastrectomy in 4 patients. No recurrence was experienced during a median of 53 months of follow-up. All NET G2 was treated with gastrectomy. No patient experienced recurrence during a median of 25 months of follow-up. NET G3 was treated with gastrectomy. One patient died of liver metastasis 52 months after gastrectomy. For NEC, gastrectomy was performed in 3 cases and no patients died of tumor-related death. We conclude that the prognoses of NET G1 and G2 were good. We also experienced long-term survivors of NEC. An accumulation of more patients is needed for further investigation.


International Surgery | 2014

Prognostic Factors for Gastrectomy in Elderly Patients

Shunji Endo; Yukinobu Yoshikawa; Nobutaka Hatanaka; Tsutomu Dousei; Terumasa Yamada; Junichi Nishijima; Wataru Kamiike

The decision to undergo surgery for gastric cancer patients aged ≥85 years should be made carefully. We retrospectively reviewed the prognostic factors of gastrectomy for 64 patients aged ≥85 years who had undergone curative gastrectomy for gastric cancer. The effects of various clinical characteristics and surgical interventions on survival were retrospectively analyzed. Univariate analysis revealed that sex (male/female; P = 0.001), the extent of gastric resection (total/distal; P = 0.028), the extent of lymph node dissection (D2/<D2; P = 0.019), and blood loss (P = 0.005) were significant prognostic factors for overall survival. Multivariate analysis demonstrated that sex was the only independent prognostic factor. For pneumonia-specific survival, sex was also the only prognostic factor by multivariate analysis.Prognoses of males aged ≥85 years after gastrectomy were significantly worse than those of females, as they were more likely to die of pneumonia.


International Journal of Clinical Oncology | 2006

Unresectable gastric cancer with multiple liver metastases effectively treated with combined paclitaxel and doxifluridine chemotherapy

Shin Mizutani; Tsukasa Oyama; Nobutaka Hatanaka; Fumihiro Uchikoshi; Katsuhide Yoshidome; Masayuki Tori; Shigeyuki Ueshima; Masaaki Nakahara; Kazuyasu Nakao

We report a 72-year-old man who was diagnosed by gastroscopy as having a type III poorly differentiated adenocarcinoma in the lesser curvature, with the longest diameter being 10 cm. An abdominal computed tomography (CT) scan revealed multiple liver metastases, thickening of the gastric wall, and an enlarged paraaortic lymph node. The serum carcinoembryonic antigen (CEA) level was 60 ng/ml and the carbohydrate antigen (CA) 19–9 level was 1355 U/ml. The patient received combined chemotherapy with doxifluridine (800 mg/body per day) and paclitaxel (one course comprised three weekly infusions at a dose of 70 mg/m2 followed by 1-week rest). After the completion of three courses, the patient achieved a complete response (CR), with complete disappearance of the primary tumor, the metastatic foci in the liver, and the enlarged abdominal lymph nodes; as well, the tumor markers were normalized. Adverse effects included only mild anorexia that was limited to grade 1. He maintained a CR for 1 year and 2 months. Combination chemotherapy with paclitaxel and doxifluridine can be an effective treatment for unresectable advanced gastric carcinoma.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 1998

Mediastinal bronchogenic cyst associated with high serum level of CA19-9 —A surgical case report—

Yasuo Sumi; Kiyoshi Ohno; Yoshio Yamasaki; Nobutaka Hatanaka; Shigetaka Yamamoto; Keiji Kuwata

We reported a case of mediastinal bronchogenic cyst in a patient with a high serum level of CA19-9. The patient, a 41-year-old man, presented with a complaint of persistent fever. Chest X-ray examination, computed tomography and magnetic resonance imaging showed a subcarinal mass shadow which was diagnosed preoperatively as a bronchogenic cyst. The serum level of CA19-9 was 73 U/ml. The cyst was partially removed via right thoracotomy. Histopathological findings were compatible with bronchogenic cyst. The CA19-9 level in the specimen was 134,00 U/ml. The serum level of CA19-9 decreased to normal postoperatively. The postoperative course was uneventful.

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Shigeomi Shimizu

Tokyo Medical and Dental University

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