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Featured researches published by Osamu Totsuka.


Transplantation | 2002

Effects of a p38 mitogen-activated protein kinase inhibitor as an additive to Euro-Collins solution on reperfusion injury in canine lung transplantation1.

Naoki Hashimoto; Izumi Takeyoshi; Daisuke Yoshinari; Hirofumi Tsutsumi; Masahiko Tokumine; Osamu Totsuka; Yutaka Sunose; Susumu Ohwada; Koshi Matsumoto; Yasuo Morishita

Background. The activation of p38 mitogen-activated protein kinase (MAPK) plays an important role in the development of ischemia/reperfusion injury. FR167653 is a novel p38 MAPK inhibitor. This study evaluated the effects of p38 MAPK inhibition during cold ischemia on subsequent reperfusion injury using FR167653 as an additive to Euro-Collins solution in canine lung transplantation. Methods. Canine orthotopic left lung transplantation was performed after 12-hr cold storage using Euro-Collins solution, with or without FR167653. Fifteen minutes after reperfusion, the right pulmonary artery and the right stem bronchus were ligated, and the animals were observed for 4 hr after reperfusion. Left pulmonary vascular resistance (L-PVR), cardiac output (CO), arterial oxygen pressure (Pao2), and alveolar-arterial oxygen pressure difference (A-aDo2) were measured. Lung specimens were harvested for wet-to-dry lung weight ratio (WDR) measurements, histopathologic studies, and polymorphonuclear neutrophil (PMN) counts. The activities of p38 MAPK in lung grafts were evaluated. Results. The addition of FR167653 significantly (P <0.05) improved Pao2, A-aDo2, L-PVR, CO, and WDR and suppressed PMN infiltration after transplantation. FR167653 also ameliorated histologic damage to the lung graft. During cold storage, p38 MAPK was not activated in the lung graft, whereas it was markedly activated 30 min after reperfusion. FR167653 significantly (P <0.05) inhibited p38 MAPK activation 30 min after reperfusion. Conclusions. The addition of FR167653 to Euro-Collins solution improved lung graft viability associated with the inhibition of p38 MAPK activation. These results suggest that inhibiting p38 MAPK activation may attenuate ischemia/reperfusion injury in lung transplantation.


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2013

Three-dimensional computed tomography for analyzing the vascular anatomy in laparoscopic surgery for right-sided colon cancer.

Keitaro Hirai; Daisuke Yoshinari; Hiroomi Ogawa; Seshiru Nakazawa; Yoshiaki Takase; Kazumi Tanaka; Yohei Miyamae; Norifumi Takahashi; Hiroshi Tsukagoshi; Hiroyuki Toya; Osamu Totsuka; Yutaka Sunose; Izumi Takeyoshi

Background: The mesenteric vessels have many branching patterns. This study clarified the anatomic relationship between the superior mesenteric vein (SMV), the right colic artery (RCA), and the ileocolic artery (ICA) using 3-dimensional computed tomography (3D-CT). The relationship between the RCA and the right colic vein (RCV) was also examined. Methods: Between April 2006 and July 2011, all patients with colorectal cancer underwent multidetector computed tomography (MDCT) before laparoscopic surgery. The 100 most recent consecutive cases were analyzed. 3D-CT images were made by combining arterial angiography, venous angiography, colonography, tumor, lymph node, and duodenal images. Results: The RCA branched from the SMA in 37 cases (37%); of these, 21 had an ICA that crossed anterior to the SMV and 16 had an ICA that crossed posterior. When the ICA crossed anterior to the SMV, all had an RCA that crossed anterior to the SMV, and no posterior RCA was seen. Furthermore, the RCV joined the SMV in 10 cases (27%) and the gastrocolic trunk in 27 cases (73%). Conclusions: Our study clarified the anatomic variety of the vessels in right-sided colon cancer. Preoperative 3D-CT is useful for understanding the anatomy to ensure a safe, precise operation.


Journal of Heart and Lung Transplantation | 2004

Effects of a bradykinin B2 receptor antagonist on ischemia–reperfusion injury in a canine lung transplantation model

Naoki Hashimoto; Izumi Takeyoshi; Hirofumi Tsutsumi; Yutaka Sunose; Masahiko Tokumine; Osamu Totsuka; Susumu Ohwada; Koshi Matsumoto; Yasuo Morishita

BACKGROUND This study investigated the effects of a bradykinin B(2) receptor antagonist, FR173657 (FR), on ischemia-reperfusion (I/R) injury in a canine lung transplantation model. METHODS Eighteen pairs of weight-matched dogs were randomly divided into 3 groups. Six pairs were assigned to the FR(D+R) group, in which FR (100 nmol/kg/h) was administered to the transplant donor continuously beginning 30 minutes before ischemia until the onset of ischemia, and FR was administered to the transplant recipient beginning 30 minutes before reperfusion and continuing for 2 hours after reperfusion. Another 6 pairs of dogs were assigned to the FR(R) group, in which FR was administered only to the recipient in the same manner as in the FR(D+R) group. The other pairs were assigned to the control group, in which vehicle alone was administered. Orthotopic left lung transplantation was performed after 12-hour cold storage in Euro-Collins solution. Fifteen minutes after reperfusion, the right pulmonary artery and the right stem bronchus were ligated. The animals were measured for 4 hours after reperfusion for left pulmonary vascular resistance (L-PVR), cardiac output (CO), arterial oxygen pressure (PaO(2)) and alveolar-arterial oxygen pressure difference (A-aD(O(2))). Lung specimens were harvested for measurement of the wet-to-dry lung weight ratio (WDR), histopathologic studies and polymorphonuclear neutrophil (PMN) count. RESULTS Compared with the control group, PaO(2), A-aDO(2), L-PVR and CO were all significantly (p < 0.05) improved and WDR significantly (p < 0.05) lower in both the FR(D+R) and FR(R) groups. Moreover, in the FR-treated groups, histologic tissue edema was mild, and PMN infiltration was significantly (p < 0.05) reduced. CONCLUSIONS The bradykinin B(2) receptor antagonist, FR173657, ameliorates I/R injury in lung grafts, indicating that protection of lung grafts can be achieved by the administration of FR solely to the transplant recipient.


Digestive Diseases and Sciences | 2005

Bradykinin B2 Receptor Antagonist FR173657 Ameliorates Small Bowel Ischemia–Reperfusion Injury in Dogs

Kazuhisa Arakawa; Izumi Takeyoshi; Yoshihiko Akao; Osamu Totsuka; Koshi Matsumoto; Yasuo Morishita

Bradykinin mediates acute inflammation by increasing microvascular permeability, vasodilation, leukocyte migration and accumulation, and the production of arachidonic acid via phospholipase A2 activation. Arachidonic acid metabolites, or eicosanoids, are potent modulators of biological functions, particularly inflammation. Bradykinin exerts its inflammatory effects via the bradykinin B2 receptor. The aim of this study was to evaluate the effect of a bradykinin B2 receptor antagonist, FR173657 (FR), on intestinal ischemia-reperfusion (I/R) injury. Twenty-eight mongrel dogs were divided into four groups (n = 7 per group). Group I underwent I/R alone, Group II underwent I/R and received FR treatment, Group III was sham operated, and Group IV was sham operated and received FR treatment. The FR treatment consisted of FR continuously from 30 min prior to ischemia to 2 hr after reperfusion. In the I/R procedure, the superior mesenteric artery (SMA) and vein were clamped for 2 hr and then released to permit reperfusion for 12 hr. The intramucosal pH (pHi), SMA blood flow, and mucosal tissue blood flow were measured during the reperfusion period. The serum thromboxane B2 and 6-keto-prostaglandin F1α levels were determined, and tissue samples were examined histologically. Results showed that tissue blood flow, pHi, and SMA blood flow after reperfusion were maintained in Group II in comparison with Group I. Histopathological examination showed less severe mucosal damage after reperfusion in Group II than in Group I. The serum thromboxane B2 and 6-keto-prostagland in F1α levels were significantly lower in Group II than in Group I (P < 0.05). We conclude that FR treatment appears to have clear protective effects on small bowel I/R injury by inhibiting the release of eicosanoids.


Journal of Heart and Lung Transplantation | 2002

Effects of a bradykinin B2 receptor antagonist, FR173657, on pulmonary ischemia–reperfusion injury in dogs

Naoki Hashimoto; Izumi Takeyoshi; Hirofumi Tsutsumi; Yutaka Sunose; Masahiko Tokumine; Osamu Totsuka; Susumu Ohwada; Takao Yokoe; Koshi Matsumoto; Yasuo Morishita

BACKGROUND This study investigated the effects of a bradykinin B(2) receptor antagonist, FR173657 (FR), on pulmonary ischemia-reperfusion (I/R) injury. METHODS Twenty-four mongrel dogs were divided into four groups (n = 6 each). In Groups I, II and III, FR doses of 33, 100 and 300 nmol/kg per hour, respectively, were administered continuously beginning 30 minutes before ischemia and continuing for 2 hours after reperfusion. In Group IV, vehicle alone was administered. Warm ischemia was induced for 3 hours by clamping the left pulmonary artery and veins. Simultaneously, the left stem bronchus was bisected and then anastomosed before reperfusion. Fifteen minutes after reperfusion, the right pulmonary artery and bronchus were ligated. Left pulmonary vascular resistance (L-PVR), cardiac output (CO), arterial oxygen pressure (PaO(2)) and the alveolar - arterial oxygen pressure difference (A-aDO2) were measured for 4 hours after reperfusion. Lung tissue was harvested for wet-to-dry weight ratio (WDR) measurements, histopathologic studies and polymorphonuclear neutrophil (PMN) counts. Serum thromboxane (TX) B(2), 6-keto-prostaglandin (PG) F(1alpha) and leukotriene (LT) B(4) levels were also measured. RESULTS PaO(2), A-aDO2, L-PVR and CO were significantly (p < 0.05) improved and WDR was significantly (p < 0.05) lower in Groups II and III than in Group IV. Histologic tissue edema was mild, and PMN infiltration was significantly (p < 0.05) reduced in Groups I, II and III compared with Group IV. TXB(2) levels were significantly (p < 0.05) lower in Group II than in Group IV, whereas 6-keto-PGF(1alpha) levels were not significantly different. LTB(4) levels were significantly (p < 0.05) lower in Groups II and III than in Group IV. CONCLUSIONS FR appears to have a protective effect on pulmonary I/R injury stemming from the inhibition of eicosanoid release.


Jpn J Gastroenterol Surg, Nihon Shokaki Geka Gakkai zasshi | 1999

Right Hemicolectomy for Colon Cancer and Endoscopic Microwave Coagulation Therapy for Gastric Cancer with myelodysplastic syndrome: Case Report.

Osamu Totsuka; Susumu Ohwada; Tetsushi Ogawa; Toshio Fukusato; Izumi Takeyoshi; Yoshihiro Sato; Yasuo Morishita

症例は73歳の男性で, 右下腹部痛を主訴に近医を受診し, 早期胃癌と上行結腸進行癌と診断され, 紹介入院となった. 著明な汎血球減少があり, 骨髄穿刺で骨髄異形成症候群 (myelodysplastic syndrome: MDS) のrefractory anemia with excess of blasts in transformationと診断された. 結腸癌に対し開腹手術を行った. 結腸癌は膿瘍を形成し腹壁まで浸潤していたため, 腹壁の一部と膿瘍を含めた結腸右半切除術を施行した. 病理組織学的にはss, ly0, v0, n0, stage IIであった. 周術期を準無菌室で管理し, 顆粒球ころにー刺激因子 (G-CSF) は投与せず, 白血球除去赤血球と濃厚血小板の輸注および抗生剤を投与した. 術後出血や感染などの合併症はなく退院した. 術後1 か月, 胃癌に対し内視鏡的治療を施行した. 結腸癌手術から3か月目に肺炎からの敗血症で死亡した. MDSと同時期に発見された他臓器癌に対する手術症例は少なく, 文献的考察を加えて報告した.


Journal of Heart and Lung Transplantation | 2006

Effect of the Free Radical Scavenger MCI-186 on Pulmonary Ischemia–Reperfusion Injury in Dogs

Takahiko Akao; Izumi Takeyoshi; Osamu Totsuka; Kazuhisa Arakawa; Masato Muraoka; Katsumi Kobayashi; Kenjiro Konno; Koshi Matsumoto; Yasuo Morishita


World Journal of Gastroenterology | 2007

Effect of atrial natriuretic peptide on ischemia-reperfusion injury in a porcine total hepatic vascular exclusion model

Katsumi Kobayashi; Kiyohiro Oshima; Masato Muraoka; Takahiko Akao; Osamu Totsuka; Hisashi Shimizu; Hiroaki Sato; Kazumi Tanaka; Kenjiro Konno; Koshi Matsumoto; Izumi Takeyoshi


Hepato-gastroenterology | 2005

Effects of a free radical scavenger, MCI-186, on ischemia-reperfusion injury during extended liver resection in dogs.

Osamu Totsuka; Izumi Takeyoshi; Hirofumi Tsutsumi; Kazuhisa Arakawa; Takahiko Akao; Masato Muraoka; Susumu Ohwada; Koshi Matsumoto; Yasuo Morishita


Journal of Surgical Research | 2002

Advantages of Celsior solution in graft preservation from non-heart-beating donors in a canine liver transplantation model.

Susumu Ohwada; Yutaka Sunose; Masaaki Aiba; Hirofumi Tsutsumi; Shigeru Iwazaki; Osamu Totsuka; Koshi Matsumoto; Izumi Takeyoshi; Yasuo Morishita

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