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Featured researches published by Matsuo Nagata.


Gastric Cancer | 2010

High preoperative neutrophil-lymphocyte ratio predicts poor survival in patients with gastric cancer

Hideaki Shimada; Nobuhiro Takiguchi; Osamu Kainuma; Hiroaki Soda; Atsushi Ikeda; Akihiro Cho; Akinari Miyazaki; Hisashi Gunji; Hiroshi Yamamoto; Matsuo Nagata

BackgroundThe neutrophil-lymphocyte ratio (NLR) reflects inflammatory status. An elevated NLR has been reported to be a prognostic indicator in some malignant tumors. The aim of this study was to evaluate the clinical significance of the preoperative NLR in patients with primary gastric cancer.MethodsA total of 709 men and 319 women, with a mean age of 64.4 years, who underwent gastrectomy were included. The numbers of patients in each pathological stage were as follows: stage I, 584; stage II, 132; stage III, 153; and stage IV, 159. The mean NLR was 2.62 ± 1.68. A total of 127 patients (12.4%) with an NLR of 4.0 or more were classified as high NLR individuals in this study. The prognostic significance of a high NLR, together with various clinicopathological factors, was evaluated by multivariate analysis.ResultsThe 5-year survival of patients with a high NLR was significantly worse than that of patients with a low NLR (57% vs 82%, P < 0.001). Univariate and multivariate analyses of clinicopathological factors affecting survival revealed that high NLR, depth of tumor, positive lymph nodes, distant metastasis, peritoneal metastasis, poorly differentiated type, and high platelet count were significant risk factors for reduced survival. On multivariate analysis, after adjusting for tumor stage, a high NLR was an independent risk factor for reduced survival (P = 0.003; adjusted hazard ratio, 1.845; 95% confidence interval, 1.236–2.747).ConclusionA high preoperative NLR may be a convenient biomarker to identify patients with a poor prognosis after resection for primary gastric cancer.


Transplantation | 1987

Studies of the induction and maintenance of long-term graft acceptance by treatment with FK506 in heterotopic cardiac allotransplantation in rats.

Takenori Ochiai; Kazuaki Nakajima; Matsuo Nagata; Seiji Hori; Takehide Asano; Kaichi Isono

Immunosuppressive activities of the newly discovered FK506, isolated from Streptomyces tsukubaensis, were examined by using cardiac allotransplantation in the rat, and the mechanisms underlying induction and maintenance of FK506-induced long-term allograft survival were studied. Male rats of WKA (RT1k) and F344 (RT1Iv1) strains were used as recipients and donors, respectively, and those of BN (RT1n) strain were used as third-party donors. Treatment with FK506, beginning from the day of allografting for 14, 10, or as few as 4 days, prolonged allograft survival significantly across the major histocompatibility barrier. The minimum doses for prolonging graft survival were 0.1 mg/kg/day by intramuscular treatment and 1.0 mg/kg/day by oral treatment. Treatment with FK506 at a dose of 0.32 mg/kg/day from day 4 until day 10 resulted in all the grafts surviving indefinitely and from days 5 to 10, half the grafts survived indefinitely, suggesting that the agent inhibited ongoing rejection. On the other hand, cyclosporine treatment at a dose of 20 mg/kg/day from day 2 did not prolong graft survival time statistically significantly. Induction of prolonged graft survival was not obtained by pretreatment of the prospective donor or recipient; prolonging effects were observed only when the agent was administered after allografting. Thus, the primary effect of the agent is exerted on responder lymphocytes reacting to the donor antigens in the induction phase of long-term graft acceptance. The mechanisms underlying the maintenance of long-term grafts were analyzed by testing the capacity of lymphocytes or serum of long-term graft-bearing rats to inhibit graft rejection in irradiated grafted hosts. Transfer of 2×108 lymphocytes from FK506-induced long-term F344 graft-bearing WKA rats resulted in indefinite survival of F344 heart allografts, but it did not prolong survival of third-party BN hearts. Transfer of 2.5 ml serum from long-term graft-bearing rats also prolonged graft survival of F344 hearts, but not BN hearts. These results suggest that donor strain–specific suppressor cells and humoral factor(s) are induced by treatment with FK506 in the presence of allografts, and that they play at least partial roles in the maintenance of long-term allograft acceptance.


Transplantation | 1987

Studies of the effects of FK506 on renal allografting in the beagle dog

Takenori Ochiai; Matsuo Nagata; Kazuaki Nakajima; Takashi Suzuki; Kaoru Sakamoto; Kazuo Enomoto; Yoshio Gunji; Takeshi Uematsu; Goto T; Seiji Hori

The immunosuppressive activities of a newly discovered macrolide extracted from Streptomyces tsukubaensis, FK506, were examined using 38 renal allografts in the beagle dog. The median survival time was 15.5 days in dogs without treatment, 61 days with a dose of 0.08 mg/kg/day and 176 days with a dose of 0.16 mg/kg/day of intramuscularly administered FK506. Prolongation of survival was statistically significant when compared with controls (P = 0.02, 0.0044, respectively). None of 6 recipient dogs receiving the agent at a dose of 0.16 mg/kg/day encountered rejection during the treatment course. Three of them survived over 200 days. Oral administration of FK506 at a dose of 0.32 mg/kg/day did not prolong the median survival time (20.5 days) compared with the placebo treated control (16.5 days), but oral treatment with 1.0 mg/kg/day resulted in all of the recipient dogs surviving over 130 days. Histological studies of 7 kidney graft biopsy specimens of the dogs surviving over 3 months revealed no cell infiltration or only some degree of reversible interstitial cell infiltration, but vascular and glomerular changes were not observed in any of the specimens. Irregularity of nuclear shape and cytoplasmic vacuolation of the pars recta of the proximal tubules were observed in one dog each. Liver biopsy specimens showed no consistent evidence of hepatocellular damage. Three dogs died of intussusception 2–3 weeks posttransplant. The dogs treated intramuscularly with 0.32 mg/kg/day suffered from anorexia. Two dogs receiving oral treatment at a dose of 1.0 mg/kg developed papilloma of the skin around day 60, but the tumors disappeared by day 120. We conclude that FK506 is a powerful immunosuppressant in the dog with tolerable side effects.


American Journal of Surgery | 2009

Comparison of laparoscopy-assisted and open pylorus-preserving pancreaticoduodenectomy for periampullary disease

Akihiro Cho; Hiroshi Yamamoto; Matsuo Nagata; Nobuhiro Takiguchi; Hideaki Shimada; Osamu Kainuma; Hiroaki Souda; Hisashi Gunji; Akinari Miyazaki; Atsushi Ikeda; Tomoko Tohma; Ikuko Matsumoto

BACKGROUND Although many reports have described laparoscopic pancreatic surgery, pancreaticoduodenectomy (PD) has not been widely accepted. The present study aimed to compare laparoscopy-assisted and open pylorus-preserving pancreaticoduodenectomy (PPPD) to investigate the feasibility, safety, and tumor clearance. METHODS Fifteen patients with periampullary disease underwent laparoscopy-assisted PPPD, in which resection was performed laparoscopically and the reconstruction was performed through a small midline incision. These patients were compared with 15 patients who, during the same period, underwent conventional open PPPD. RESULTS Mean operative time and mean blood loss were similar between groups. No significant differences in the incidence of complications or hospital stay were noted between groups. Surgical margin and number of lymph nodes found in the resected specimen did not differ between groups. CONCLUSIONS Laparoscopy-assisted PPPD is on the same level with conventional open surgery in terms of perioperative outcomes or treatment efficacy.


Surgical Endoscopy and Other Interventional Techniques | 2007

Laparoscopy-assisted hepatic lobectomy using hilar Glissonean pedicle transection

Akihiro Cho; Takehide Asano; Hiroshi Yamamoto; Matsuo Nagata; Nobuhiro Takiguchi; Osamu Kainuma; Hiroaki Souda; Hisashi Gunji; Akinari Miyazaki; H. Nojima; Atsushi Ikeda; I. Matsumoto; M. Ryu; Harufumi Makino; Shinichi Okazumi

Although many reports have described laparoscopic minor liver resections, major hepatic resection, including right or left lobectomy, has not been widely developed because of technical difficulties. This article describes a new technique for performing laparoscopy-assisted right or left hepatic lobectomy using hilar Glissonean pedicle transection. Laparoscopic mobilization of the right or left hepatic lobe is performed, including dissection of the round, faliciform, triangular, and coronary ligaments. The right or left Glissonean pedicle is encircled and divided laparoscopically. A parenchymal dissection is then performed though the upper median or right subcostal incision, through which the resected liver is removed. We successfully performed this procedure in 6 patients without blood transfusion or serious complications. Laparoscopy-assisted hepatic lobectomy using hilar Glissonean pedicle transection can be feasible and safe in highly selected patients.


Journal of Hepato-biliary-pancreatic Surgery | 2008

Renal cell carcinoma with unusual metastasis to the gallbladder

Hiroyuki Nojima; Akihiro Cho; Hiroshi Yamamoto; Matsuo Nagata; Nobuhiro Takiguchi; Osamu Kainuma; Hiroaki Souda; Hisashi Gunji; Akinari Miyazaki; Atsushi Ikeda; Ikuko Matsumoto; Takehide Asano; Munemasa Ryu; Naoki Nihei; Masayuki Maruoka

Gallbladder involvement in patients with renal cell carcinoma (RCC) is extremely rare. We present a report of a 61-year-old man with a synchronous RCC metastasis to the gallbladder presenting as an intraluminal polypoid mass simulating primary gallbladder carcinoma. Enhanced abdominal computed tomography demonstrated a well-enhanced polypoid lesion in the gallbladder. Intraoperative rapid pathological examination of the gallbladder tumor showed clear cell-type cancerous cells. Microscopically, tumor cells of both the resected kidney and gallbladder had round uniform nuclei, clear cytoplasm, and well-defined cytoplasmic borders, forming alveolar patterns. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) and carcinoembryonic antigen (CEA), which is usually positive in primary clear cell carcinoma of the gallbladder. Therefore, the final diagnosis was RCC with a synchronous gallbladder metastasis.


American Journal of Clinical Oncology | 2001

Surgical treatment for pancreatic metastasis from soft-tissue sarcoma: report of two cases.

Hiroshi Yamamoto; Kazuo Watanabe; Matsuo Nagata; Ichiro Honda; Satoshi Watanabe; Hiroaki Soda; Shinichiro Tatezaki

We present two cases in which a soft-tissue sarcoma metastasized to the pancreas, but both patients survived as a result of repetitive surgical treatment during a 6- to 10-year period. The first case was a 29-year-old man who had a history of removal of mesenchymal chondrosarcoma in the left thigh in 1986 and who underwent distal pancreatectomy and the enucleation of a tumor in the head of the pancreas because of the development of three metastatic lesions in 1989. Afterward, although metastases were found in other organs, they were resected each time (for a total of five times) and the patient has survived over 10 years. The second case was a 40-year-old woman who had a history of the removal of synovial sarcoma in the right thigh and had 6 surgical resections of local or pulmonary recurrent tumors. She underwent pylorus-preserving pancreaticoduodenectomy in 1993 because of the development of a solitary metastatic lesion in the pancreas and survived more than 6 years after the pancreatectomy. Our report suggests, in selected cases, that long-term survival from pancreatic metastasis of soft-tissue sarcoma is expected as a result of curative resection. However, because pancreatic metastasis has a potential to recur in other organs, it is necessary to take aggressive surgical procedures repeatedly for the treatment of recurrences to improve prognosis after pancreatectomy.


Surgery Today | 2009

A Totally Laparoscopic Pylorus-Preserving Pancreaticoduodenectomy and Reconstruction

Akihiro Cho; Hiroshi Yamamoto; Matsuo Nagata; Nobuhiro Takiguchi; Hideaki Shimada; Osamu Kainuma; Hiroaki Souda; Hisashi Gunji; Akinari Miyazaki; Atsushi Ikeda; Tomoko Tohma

AbstractAlthough many reports have described laparoscopic pancreatic surgery, laparoscopic pancreaticoduodenectomy (PD) has not been widely employed because of technical difficulties. This paper describes a totally laparoscopic pylorus-preserving PD performed for an intraductal papillary-mucinous neoplasm. After the laparoscopic resection, an end-to-side pancreaticojejunostomy including duct-to-mucosa anastomosis without a stenting tube, an approximation of the pancreas stump and jejunal wall, an end-to-side hepaticojejunostomy, and an end-to-side duodenojejunostomy were performed intracorporeally. The patient recovered without any complications and was discharged on the 14th postoperative day. The surgical margin was free of neoplastic changes. Although the experience is limited and the appropriate indications must await future studies, this case indicates that a laparoscopic pylorus-preserving PD can be feasible, safe, and effective in highly selected patients.


Surgical Endoscopy and Other Interventional Techniques | 2011

Safe and feasible extrahepatic Glissonean access in laparoscopic anatomical liver resection.

Akihiro Cho; Hiroshi Yamamoto; Osamu Kainuma; Hiroaki Souda; Atsushi Ikeda; Nobuhiro Takiguchi; Matsuo Nagata

BackgroundAlthough recent technological developments and improved endoscopic procedures have further spread the application of laparoscopic liver resection, laparoscopic anatomical liver resection still presents major technical difficulties, such as pedicle control.MethodsSubjects comprised 27 patients who underwent laparoscopic anatomical liver resection using an extrahepatic Glissonean pedicle transaction between August 2005 and February 2010.ResultsA total of 61 Glissonean pedicles could be encircled en bloc extrahepatically, as planned. No serious complications, including major bleeding or injury of the portal triad, were encountered during procedures.ConclusionsExtrahepatic Glissonean access seems to be feasible and safe for laparoscopic anatomical resection of the liver.


Surgical Endoscopy and Other Interventional Techniques | 2009

Safe and feasible inflow occlusion in laparoscopic liver resection

Akihiro Cho; Hiroshi Yamamoto; Matsuo Nagata; Nobuhiro Takiguchi; Hideaki Shimada; Osamu Kainuma; Hiroaki Souda; Hisashi Gunji; Akinari Miyazaki; Atsushi Ikeda

Background A major challenge in laparoscopic liver resection to avoid massive hemorrhage from the transection plane.

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