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Dive into the research topics where Takatsugu Yamada is active.

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Featured researches published by Takatsugu Yamada.


Annals of Surgery | 1996

Significant influence of accompanying chronic hepatitis status on recurrence of hepatocellular carcinoma after hepatectomy. Result of multivariate analysis.

Saiho Ko; Yoshiyuki Nakajima; Hiromichi Kanehiro; Michiyoshi Hisanaga; Yukio Aomatsu; Tastuya Kin; Kazuaki Yagura; Takao Ohyama; Kazushi Nishio; Kazuo Ohashi; Masayuki Sho; Takatsugu Yamada; Hiroshige Nakano

OBJECTIVE The aim of this study was to evaluate the correlation between the histologic status of accompanying chronic hepatitis and the recurrence rate of hepatocellular carcinoma (HCC) after hepatectomy by multivariate analysis. SUMMARY BACKGROUND DATA Recent studies have suggested that a considerable number of intrahepatic recurrence of HCC after hepatectomy might be the results of metachronous multicentric hepatocarcinogenesis. The authors hypothesized that the incidence of recurrence due to metachronous multicentric hepatocarcinogenesis would depend on the histologic status of accompanying chronic viral liver disease, which is a main promoter of HCC. METHODS One hundred ten patients with HCC who underwent curative resection were studied. Histologic status of accompanying chronic hepatitis was classified into the three categories: 1) normal liver or chronic persistent hepatitis (CPH, n = 13), 2) chronic aggressive hepatitis (CAH, n = 50), and 3) liver cirrhosis (LC, n = 47). RESULTS The Cox multivariate proportional hazard model showed that the accompanying chronic viral hepatitis status (p = 0.0133), extent of hepatectomy (p = 0.0078), and number of tumors (p = 0.0475) were significantly predictive variables for recurrence-free survival. By the log-rank test, recurrence-free survival rate in patients with CPH was significantly higher than those in patients with CAH (p = 0.0005) and LC (p = 0.0075). Patients with CAH had the lowest recurrence-free survival rate (vs. LC, p = 0.028). CONCLUSIONS The results of this study indicated the significant influence of histologic activity of hepatitis on recurrence of HCC. This might support the concept of significant contribution of multicentric hepatocarcinogenesis to recurrence of HCC after hepatectomy.


World Journal of Surgery | 1998

Pattern of Recurrence after Resection for Intraductal Papillary Mucinous Tumors of the Pancreas

Masayuki Sho; Yoshiyuki Nakajima; Hiromichi Kanehiro; Michiyoshi Hisanaga; Kazushi Nishio; Mitsuo Nagao; Naoya Ikeda; Hideki Kanokogi; Takatsugu Yamada; Hiroshige Nakano

Abstract. The objective of this study was to clarify the patterns of recurrence and prognosis after resection of intraductal papillary mucinous tumors (IPMTs). Fourteen patients with IPMT were reviewed histologically; intraductal papillary adenocarcinoma was present in 12 cases and intraductal papillary adenoma in 2. Six patients were alive with no evidence of disease. Two patients died from other causes. Six patients had recurrences. The median survival time was 46 months. In the six recurrent cases, the median postoperative disease-free interval was 38 months. Four patients died of recurrence, and the median survival time after recurrence was 6 months. The major site of recurrence was the remnant pancreas. The other sites were the liver in two cases, peritoneum in two, and local in one. These results suggest the multicentric or metachronous oncogenesis of IPMT. Because of the low frequency of lymph node metastases, an operation to preserve pancreatic function may be recommended, especially for localized tumors such as the branch type. It is important to avoid an incomplete resection using intraoperative pancreatoscopy and ultrasonography. Long-term follow-up after surgery is necessary even for a curative resection. We should perform total pancreatectomy for recurrences without distant metastases.


World Journal of Surgery | 1998

Serum Interleukin-6, Interleukin-8, Hepatocyte Growth Factor, and Nitric Oxide Changes during Thoracic Surgery

Takatsugu Yamada; Michiyoshi Hisanaga; Yoshiyuki Nakajima; Hiromichi Kanehiro; Akihiko Watanabe; T Ohyama; Kazushi Nishio; Masayuki Sho; Mitsuo Nagao; Akihisa Harada; Kouji Matsushima; Hiroshige Nakano

Abstract. Thoracic surgery creates a different environment from abdominal surgery in respect to the surgical procedure with pulmonary collapse under unilateral ventilation. Definitive evidence whether surgical trauma during thoracotomy is involved in postoperative pulmonary infections has not been clearly demonstrated. The objectives of this study were to evaluate the influence of surgical trauma during thoracotomy on postoperative infections and to investigate the clinical significance of postoperative humoral mediators in pulmonary infections after surgery. We measured serum interleukin-6 (IL-6), IL-8, hepatocyte growth factor (HGF), and nitric oxide (NO) levels in 27 patients undergoing thoracic surgery; the measurements were before and during thoracotomy, 60 minutes after reinflation, and after surgery. The patients were divided into three groups: lobectomy patients (group A), and esophagectomy patients without (group B) or with (group C) postoperative infections. The serum IL-6 and IL-8 levels in group C were markedly elevated 60 minutes after reinflation and were significantly higher than those in group A. The serum IL-8 levels during that period in group C were significantly higher than those in group B. The postoperative serum IL-6, IL-8, HGF, and NO levels were significantly higher in group C than in group B. Taken together, intraoperative hypercytokinemia, especially IL-8, following the thoracic procedure and subsequent reinflation preceded the clinical onset of postoperative infections. Hence postoperative serum IL-6, IL-8, and HGF levels may be useful predictors of infection after esophagectomy.


American Journal of Surgery | 1998

A new evaluation of pancreatic function after pancreatoduodenectomy using secretin magnetic resonance cholangiopancreatography

Masayuki Sho; Yoshiyuki Nakajima; Hiromichi Kanehiro; Michiyoshi Hisanaga; Kazushi Nishio; Mitsuo Nagao; Yukihiro Tatekawa; Naoya Ikeda; Hideki Kanokogi; Takatsugu Yamada; Shinji Hirohashi; Rina Hirohashi; Hideo Uchida; Hiroshige Nakano

BACKGROUND The remnant pancreatic function after pancreatoduodenectomy influences greatly postoperative quality of life. However, it has been difficult to evaluate the exocrine remnant pancreatic function postoperatively. The aim of this study was to assess the usefulness of secretin-stimulated magnetic resonance cholangiopancreatography (secretin MRCP) in evaluating the remnant pancreatic function and ascertaining the anastomotic patency after pancreatoduodenectomy. METHODS Thirty-four patients who underwent pancreatoduodenectomy were evaluated with secretin MRCP. The results of MRCP were determined by the amount of exocrine pancreatic secretion, and were graded as follows: grade I (poor secretion), grade II (moderate secretion), and grade III (good secretion). RESULTS Secretin MRCP could visualize the pancreatic secretion dynamically. MRCP grades were grade I in 11 patients, grade II in 12, and grade III in 11. There was a significant correlation between MRCP grade and glucose tolerance. We confirmed visually the patency of the anastomotic site in 24 patients (71%). MRCP grades correlated significantly with clinical symptoms. CONCLUSION Our results demonstrated secretin MRCP was feasible for evaluating the remnant pancreatic function after pancreatoduodenectomy.


Journal of Gastroenterology | 1997

Primary adenocarcinoma of appendix, colonic type associated with perforating peritonitis in an elderly patient

Takatsugu Yamada; Yoshinori Murao; Tatsuya Nakamura; Hisayuki Tabuse; Seiji Miyamoto; Shunsuke Imai; Hiroshige Nakano

We report a case of colonic type adenocarcinoma of the appendix with perforating peritonitis in a 92-year-old man. The preoperative diagnosis was localized peritonitis due to acute appendicitis and emergency laparotomy was performed. A gray, hard tumor was palpated at the base of the appendix. Appendiceal cancer was suspected, and right hemicolectomy was performed. The histopathological diagnosis was moderately differentiated adenocarcinoma of the appendix. The tumor obstructed the orifice of the appendix, and this may have caused the perforation of the appendix. The patient had an uneventful postoperative course and there have been no signs of recurrence in the 2 years since the operation.


Surgery Today | 2010

Malignant potential of intraductal papillary mucinous neoplasms of the pancreas.

Yoshiyuki Nakajima; Takatsugu Yamada; Masayuki Sho

An intraductal papillary mucinous neoplasm (IPMN) is now a well-recognized disease entity. In general, the prognosis of IPMN is much more favorable than that of pancreatic ductal adenocarcinoma (PDAC). However, IPMN has a broad biological spectrum and it sometimes progresses, slowly showing neoplastic transformations. International consensus guidelines have been recently proposed for the management of IPMN. While they significantly contribute to appropriate management of IPMN, various issues including the natural history and malignant potential of IPMN are not fully elucidated. This review focuses on the malignant potential, including the postoperative recurrence of IPMN, coincidence of IPMN with PDAC, and extrapancreatic malignancy that may affect the long-term survival of the patients rather than IPMN itself.


Methods of Molecular Biology | 2006

Derivation and Characterization of Gut-Like Structures From Embryonic Stem Cells

Takatsugu Yamada; Yoshiyuki Nakajima

Embryonic stem (ES) cells have a pluripotent ability to differentiate into a variety of cell lineages of all three embryonic germ layers in vitro. The hanging drop culture of ES cell suspension in the absence of leukemia inhibitory factor induces aggregation and differentiation of the cells into simple or cystic embryoid bodies (EBs). After 6 d of hanging drop culture, the resulting EBs are plated onto plastic dishes for the outgrowth culture. At d 21 after outgrowth culture, cell populations of EBs can give rise to three-dimensional gut-like structures that exhibit spontaneous contraction and highly coordinated peristalsis. The gut-like structures have large lumens surrounded by three layers: epithelium, lamina propria, and muscularis. Ganglia are scattered along the periphery, and interstitial cells of Cajal are distributed among the smooth muscle cells. The fundamental process of formation of the in vitro organized gut-like structures is similar to embryonic gastrointestinal development in vivo. The EBs at the 6-d egg-cylinder stage may have the potential to regulate developmental programs associated with cell lineage commitment and provide an appropriate microenvironment to differentiate ES cells into enteric derivatives of all three embryonic germ layers and reproduce the gut organization process in vitro.


Recent results in cancer research | 1998

Hyperthermo-Chemo-Hypoxic Isolated Liver Perfusion for Hepatic Metastases: A Possible Adjuvant Approach

Yoshiyuki Nakajima; Masato Horikawa; Tatsuya Kin; T Ohyama; Hiromichi Kanehiro; Michiyoshi Hisanaga; Kazushi Nishio; Mitsuo Nagao; Masayuki Sho; Takatsugu Yamada; Kazuo Ohashi; Saiho Ko; Hiroshige Nakano

As a possible intraoperative adjuvant approach to treating hepatic metastases we developed a method of hyperthermo-chemo-hypoxic isolated liver perfusion in combination with hepatic resection. This method was applied to 11 patients with colorectal hepatic metastases between 1992 and 1995. One patient died on postoperative day 14 of hepatic failure (9% mortality), the cause of which was live temperature that reached 42.9 degree C, which seems to be the maximum limit for thermal toxic effect on the human liver. The other 10 patients tolerated the perfusion well, with mild hepatic and non systemic toxicity after minor or even major hepatic resection; the serum aminotransferase and total bilirubin levels returned to normal levels by postoperative day 14. Only one of eight patients (13%) for whom cytotoxic drugs were added to the perfusate (mitomycin C 10 micrograms/ml or cisplatin 2 micrograms/ml) had hepatic recurrence by 19 months after the perfusion (mean follow-up 25.8 months; median 23 months; range 8-57 months). Two patients were alive with no evidence of disease at 13 and 57 months, respectively after the perfusion; the other five patients had postperfusion extrahepatic recurrences (median: 19 months; range 7-20 months). In contrast, hepatic metastases recurred 7 and 20 months after the perfusion, respectively, in the two patients not given a cytotoxic drug.


Journal of Surgical Oncology | 2016

The prognosis of liver resection for patients with four or more colorectal liver metastases has not improved in the era of modern chemotherapy

Daisuke Hokuto; Takeo Nomi; Ichiro Yamato; Satoshi Yasuda; Shinsaku Obara; Takahiro Yoshikawa; Chihiro Kawaguchi; Takatsugu Yamada; Hiromichi Kanehiro; Yoshiyuki Nakajima

The impact of perioperative chemotherapy on patients with multiple colorectal liver metastases (CRLM) remains unclear. We attempted to examine whether the introduction of modern chemotherapies has improved the prognosis of patients that undergo liver resection for ≥4 CRLM.


International Journal of Surgery Case Reports | 2015

Huge hepatocellular carcinoma with multiple intrahepatic metastases: An aggressive multimodal treatment

Satoshi Yasuda; Takeo Nomi; Daisuke Hokuto; Ichiro Yamato; Shinsaku Obara; Takatsugu Yamada; Hiromichi Kanehiro; Yoshiyuki Nakajima

Highlights • To the best of our knowledge, this case was, the largest HCC that had been previously reported to be resected safely.• We could avoid spontaneous tumor rupture although its risk was thought to be high.• We could control multiple intrahepatic metastases in the remnant liver with repeated TACEs after hepatectomy.• Multimodal treatment involving hepatectomy and TACE might be a good treatment strategy.

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Yoshiyuki Nakajima

National Archives and Records Administration

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Hiromichi Kanehiro

National Archives and Records Administration

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Masayuki Sho

Nara Medical University

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Mitsuo Nagao

Nara Medical University

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Takeo Nomi

Nara Medical University

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