Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Takafumi Abo is active.

Publication


Featured researches published by Takafumi Abo.


Journal of Surgical Oncology | 2011

Prognosis of patients with hepatocellular carcinoma after hepatic resection: Are elderly patients suitable for surgery?

Atsushi Nanashima; Takafumi Abo; Takashi Nonaka; Hidetoshi Fukuoka; Shigekazu Hidaka; Hiroaki Takeshita; Tatsuki Ichikawa; Terumitsu Sawai; Toru Yasutake; Kazuhiko Nakao; Takeshi Nagayasu

The indication for hepatectomy is still controversial in elderly patients with hepatocellular carcinoma (HCC). We examined the clinicopathological features and survival of 188 HCC patients who underwent hepatectomy.


Journal of Surgical Oncology | 2008

Relationship between pattern of tumor enhancement and clinicopathologic characteristics in intrahepatic cholangiocarcinoma

Atsushi Nanashima; Yorihisa Sumida; Takafumi Abo; Masayuki Oikawa; Goshi Murakami; Hiroaki Takeshita; Hidetoshi Fukuoka; Shigekazu Hidaka; Takeshi Nagayasu; Ichiro Sakamoto; Terumitsu Sawai

Common enhancement pattern of intrahepatic cholangiocarcinoma (ICC) on computed tomography (CT) is that of hypovascular enhancement; however, in some cases, tumor shows identical enhancement in the arterial phase to that in hepatocellular carcinoma. To identify the specific characteristics of different enhancement patterns, we examined the relationship between CT enhancement pattern and clinicopathological features or postoperative prognosis.


Journal of Gastroenterology | 2006

Modified Japan Integrated Staging is currently the best available staging system for hepatocellular carcinoma patients who have undergone hepatectomy

Atsushi Nanashima; Yorihisa Sumida; Takafumi Abo; Hisakazu Shindou; Hidetoshi Fukuoka; Hiroaki Takeshita; Shigekazu Hidaka; Kenji Tanaka; Terumitsu Sawai; Toru Yasutake; Takeshi Nagayasu; Katsuhisa Omagari; Mariko Mine

BackgroundWe previously reported the effectiveness of the modified Cancer of the Liver Italian Program (CLIP) score in hepatocellular carcinoma (HCC) staging. To determine the best predictive staging system for HCC patients, we conducted a comparative analysis of prognosis using multivariate analysis in 230 Japanese HCC patients following hepatic resection.MethodsWe compared overall survival as predicted by different staging systems: the tumor node metastasis (TNM) system by the Liver Cancer Study Group of Japan, the Japan Integrated Staging (JIS) score (Japanese TNM and Child-Pugh classification), the modified JIS score using liver damage grade, the CLIP score, and our modified CLIP score using protein induced by vitamin K absence or the antagonist II (PIVKA-II).ResultsBy a univariate analysis the PIVKA-II level (cut-off level, 400 mAU/ml) was significantly associated with patient survival (P = 0.031); however, alpha-fetoprotein level was not related to survival. Liver damage grade was significantly associated with patient survival (P = 0.039), although Child-Pugh classification was not related to survival. Univariate analysis showed that prediction of survival, according to disease stage, was better with the modified JIS score than with the TNM system, CLIP, modified CLIP, or JIS score. Multivariate analysis showed the modified JIS score showed the best ability to predict overall survival according to disease stage (Hazard ratio, 1.77; P = 0.002), and its Akaike information criteria statistic was the lowest (634.3).ConclusionsThe modified JIS score, a staging system that combines tumor factors and hepatic function, is a better predictor of prognosis than other systems in HCC patients who have undergone hepatic resection.


Ejso | 2015

Usefulness of intraoperative diagnosis of hepatic tumors located at the liver surface and hepatic segmental visualization using indocyanine green- photodynamic eye imaging

Takafumi Abo; Atsushi Nanashima; Syuuichi Tobinaga; Shigekazu Hidaka; Naota Taura; Katsunori Takagi; Junichi Arai; Hisamitsu Miyaaki; Hidetaka Shibata; Takeshi Nagayasu

BACKGROUND To improve the diagnostic accuracy for hepatic tumors on the liver surface, we investigated the usefulness of an indocyanine green-photodynamic eye (ICG-PDE) system by comparison with Sonazoid intraoperative ultrasonography (IOUS) in 117 patients. Hepatic segmentation by ICG-PDE was also evaluated. METHODS ICG was administered preoperatively for functional testing and images of the tumor were observed during hepatectomy using a PDE camera. ICG was injected into portal veins to determine hepatic segmentation. RESULTS Accurate diagnosis of liver tumors was achieved with ICG-PDE in 75% of patients, lower than with IOUS (94%). False-positive and false-negative diagnosis rates for ICG-PDE were 24% and 9%, respectively. New small HCCs were detected in 3 patients. The ICG fluorescent pattern in tumors was strong staining in 41%, weak staining in 13%, rim staining in 20% and no staining in 26%. Hepatocellular carcinoma predominantly showed strong staining (61%), while rim staining predominated in cholangiocellular carcinoma (60%) and liver metastasis (55%). Hepatic segmental staining was performed in 28 patients, proving successful in 89%. CONCLUSION ICG-PDE is a useful tool for detecting the precise tumor location at the liver surface, identifying new small tumors, and determining liver segmentation for liver resection.


Journal of Surgical Oncology | 2010

Usefulness of the combination procedure of crash clamping and vessel sealing for hepatic resection.

Atsushi Nanashima; Syuuichi Tobinaga; Takafumi Abo; Takashi Nonaka; Terumitsu Sawai; Takeshi Nagayasu

Minimization of blood loss during resection of the hepatic parenchyma in hepatectomy remains a major problem. The usefulness of the LigaSure sealing system has been reported.


The Journal of Thoracic and Cardiovascular Surgery | 2009

Keratinocyte growth factor accelerates compensatory growth in the remaining lung after trilobectomy in rats.

Keitaro Matsumoto; Takeshi Nagayasu; Yoshitaka Hishikawa; Tsutomu Tagawa; Takatomo Yamayoshi; Takafumi Abo; Shuichi Tobinaga; Katsuro Furukawa; Takehiko Koji

OBJECTIVE In rats pulmonary resection is followed by lung compensatory growth. However, the molecular mechanism underlying lung compensatory growth remains unclear. Keratinocyte growth factor is expressed in lung tissue and is considered a possible mitogen for lung epithelial cells. The objectives of this study were to define the role of keratinocyte growth factor and its receptor in rat lung compensatory growth after trilobectomy and the effect of exogenous keratinocyte growth factor gene transfection. METHODS Adult Lewis rats were used. Right trilobectomy was performed in the operation group and sham thoracotomy in the sham group. In the operation group, keratinocyte growth factor-FLAG or FLAG expression vector was transfected directly into the lung by means of electroporation. Expression of keratinocyte growth factor and its receptor and alveolar cell proliferation index based on proliferating cell nuclear antigen levels were measured in the right lung at day 14 after the operation. RESULTS Proliferating cell nuclear antigen, keratinocyte growth factor, and keratinocyte growth factor receptor expression in lung epithelial cells was significantly increased at day 4 after trilobectomy. Transfection of keratinocyte growth factor-FLAG expression vector resulted in further significant enhancement of proliferating cell nuclear antigen at day 4 after trilobectomy; however, the transfection of FLAG expression vector did not alter the enhancement of proliferating cell nuclear antigen. Exogenous expression of keratinocyte growth factor in the remaining lung by means of electroporation significantly augmented epithelial proliferation and decreased the average airspace distance (mean linear intercept). CONCLUSION Our results implicate keratinocyte growth factor in the induction of alveolar epithelial cell proliferation for compensatory lung growth and indicate that overexpression of keratinocyte growth factor in the remaining lung by means of electroporation significantly augmented lung epithelial proliferation.


Journal of Surgical Oncology | 2011

Usefulness of sonazoid–ultrasonography during hepatectomy in patients with liver tumors: A preliminary study

Atsushi Nanashima; Syuuichi Tobinaga; Takafumi Abo; Masaki Kunizaki; Hiroaki Takeshita; Shigekazu Hidaka; Naota Taura; Tatsuki Ichikawa; Terumitsu Sawai; Kazuhiko Nakao; Takeshi Nagayasu

To improve diagnostic accuracy of intraoperative ultrasonography (IOUS), we investigated the usefulness of new contrast medium of microbubble agent, Sonazoid as a preliminary study.


International Journal of Surgery | 2013

Usefulness of vessel-sealing devices combined with crush clamping method for hepatectomy: A retrospective cohort study

Atsushi Nanashima; Takafumi Abo; Junichi Arai; Katsunori Takagi; Hirofumi Matsumoto; Hiroaki Takeshita; Tomoshi Tsuchiya; Takeshi Nagayasu

BACKGROUND Blood loss during resection of the hepatic parenchyma in hepatectomy can be minimized using vessel-sealing (VS) devices. Some sealing devices were retrospectively compared to evaluate the efficacy of each device for controlling blood loss, transection time and postoperative complications in hepatectomy as a cohort study. METHODS Between 2005 and September 2012, hepatectomy was underwent in 150 patients using one of three types of LigaSure™ (Dolphin Tip Laparoscopic Instrument, Precise or Small Jaw) or the Harmonic Focus or Ace ultrasonic dissecting sealer. Results were compared to crush-clamping alone as the control method by the historical study (n = 81). RESULTS Irrespective of the vessel-sealing device used for underlying chronic hepatitis, blood loss, blood transfusion rate, operating time and transection time were significantly reduced in the VS group compared with controls (p < 0.05). Rates of postoperative bile leakage and intra-abdominal abscess formation were significantly lower in the VS group than in controls (p < 0.05). Comparing devices, LigaSure Small Jaw and Harmonic Focus showed lower blood loss, shorter transection time and reduced rates of post-hepatectomy complications, in turn resulting in shorter hospital stays (p < 0.05). Tendencies toward uncontrolled ascites and bile leakage were only concern with the use of Harmonic Focus. Satisfactory surgical results were achieved using the sealing device for laparoscopic hepatectomy. CONCLUSIONS The use of energy sealing devices improves surgical results and avoids hepatectomy-related complications. Adequate use of vessel sealers is necessary for safe and rapid completion of hepatic resection.


Acta Histochemica Et Cytochemica | 2010

Expression of keratinocyte growth factor and its receptor in rat tracheal cartilage: possible involvement in wound healing of the damaged cartilage.

Takafumi Abo; Takeshi Nagayasu; Yoshitaka Hishikawa; Tsutomu Tagawa; Atsushi Nanashima; Takatomo Yamayoshi; Keitaro Matsumoto; Shucai An; Takehiko Koji

Keratinocyte growth factor (KGF) is involved in the development and regeneration of a variety of tissues. To clarify the role of KGF in cartilage wound healing, we examined the expression of KGF and its receptor (KGFR) immunohistochemically in the wound healing area of rat tracheal cartilage, and the direct effect of recombinant KGF on the proliferation and differentiation of primary cultures of rat chondrocytes. KGF was found in the cytoplasm of both chondrocytes and perichondrial cells. On the other hand, KGFR was detected only in the plasma membrane of chondrocytes. Although the expression of KGF was similar in the cartilage and perichondrial area before and after injury, KGFR expression was induced after injury and limited to proliferating chondrocytes. The staining pattern of KGF and KGFR was same in the mature and the immature rat tracheal cartilage. Moreover, in vitro experiments using primary cultured chondrocytes revealed that KGF at 200 ng/ml significantly increased the number of chondrocytes (~1.5-fold), and significantly reduced acid mucopolysaccharide production. These results indicate that KGF stimulates chondrocyte proliferation, suggesting that KGF could therapeutically modulate the wound healing process in the tracheal cartilage.


Journal of Hepato-biliary-pancreatic Surgery | 2009

Usefulness of measuring hepatic functional volume using Technetium-99m galactosyl serum albumin scintigraphy in bile duct carcinoma: report of two cases

Atsushi Nanashima; Yorihisa Sumida; Takafumi Abo; Ichiro Sakamoto; Youji Ogawa; Terumitsu Sawai; Hiroaki Takeshita; Shigekazu Hidaka; Takeshi Nagayasu

We report the usefulness of measuring functional liver volume in two patients undergoing hepatectomy. Case 1 involved a 47-year-old man with hepatitis B virus infection. The indocyanine green test retention rate at 15 min (ICGR15) was 14%. Liver uptake ratio (LHL15) by technetium-99 m galactosyl human serum albumin ((99m)Tc-GSA) liver scintigraphy was 0.91. The patient displayed hilar bile duct carcinoma necessitating right hepatectomy. After preoperative portal vein embolization (PVE), future remnant liver volume became 54% and functional volume by (99m)Tc-GSA became 79%. Although the permitted resected liver volume was lower than the liver volume, scheduled hepatectomy was performed following the results of functional liver volume. Case 2 involved a 75-year-old man with diabetes. ICGR15 was 27.4% and LHL15 was 0.87. The patient displayed bile duct carcinoma located in the upper bile duct with biliary obstruction in the right lateral sector. The right hepatectomy was scheduled. After PVE, future remnant volume became 68% and functional volume became 88%. Although ICGR15 was worse as 31%, planned hepatectomy was performed due to the results of functional volume. In the liver with biliary obstruction or portal embolization, functional liver volume is decreased more than morphological volume. Measurement of functional volume provides useful information for deciding operative indication.

Collaboration


Dive into the Takafumi Abo's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge