A Novel Technique of Hand-Sewn Purse-String Suturing by Double Ligation Method (DLM) for Intracorporeal Circular Esophagojejunostomy

Takayama, Yuichi,Kaneoka, Yuji,Maeda, Atsuyuki,Fukami, Yasuyuki,Takahashi, Takamasa,Uji, Masahito The Korean Gastric Cancer Association 2019 Journal of gastric cancer Vol.19 No.3

Purpose: The optimal method for intracorporeal esophagojejunostomy remains unclear because a purse-string suture for fixing the anvil into the esophagus is difficult to perform with a laparoscopic approach. Therefore, this study aimed to evaluate our novel technique to fix the anvil into the esophagus. Materials and Methods: This retrospective study included 202 patients who were treated at our institution with an intracorporeal circular esophagojejunostomy in a laparoscopy-assisted total gastrectomy with a Roux-en-Y reconstruction (166 cases) or a laparoscopy-assisted proximal gastrectomy with jejunal interposition (36 cases). After incising 3/4 of the esophageal wall, a hand-sewn purse-string suture was placed on the esophagus. Next, the anvil head of a circular stapler was introduced into the esophagus. Finally, the circular esophagojejunostomy was performed laparoscopically. The clinical characteristics and surgical outcomes were evaluated and compared with those of other methods. Results: The average operation time was 200.3 minutes. The average hand-sewn purse-string suturing time was 6.4 minutes. The overall incidence of postoperative complications (Clavien-Dindo classification grade ${\geq}II$) was 26%. The number of patients with an anastomotic leakage and stenosis at the esophagojejunostomy site were 4 (2.0%) and 12 (6.0%), respectively. All patients with stenosis were successfully treated by endoscopic balloon dilatation. There was no mortality. Regarding the materials and devices for anvil fixation, only 1 absorbable thread was needed. Conclusions: Our procedure for hand-sewn purse-string suturing with the double ligation method is simple and safe.

Role of π-Electron Systems in Stabilization of the Oxidized Tetraheme Architecture in Cytochrome <i>c</i>₃

Takayama, Yuki,Taketa-Sato, Midori,Komori, Hirofumi,Morita, Kumiko,Kang, Su-Jin,Higuchi, Yoshiki,Akutsu, Hideo The Chemical Society of Japan 2011 Bulletin of the Chemical Society of Japan Vol.84 No.10

<P>Cytochrome <I>c</I><SUB>3</SUB> possesses four hemes in a compact configuration and exhibits extremely low reduction potentials. Besides the well-characterized factors contributing to the reduction potentials, the aromatic rings have been suggested to be involved. To elucidate its mechanism, the effect of mutations at conserved and noncoordinated aromatic residues on the reduction/oxidation properties of heme irons was investigated on the basis of crystal structures, NMR spectra of coordinated His, and reduction potentials. Phe20 parallel to heme 1 is the most conserved residue. On its mutation, the change in each coordination structure was subtle in the crystal structures despite of significant changes in the NMR spectra and reduction potentials. Significant increases in the reduction potentials of heme 1 led to the conclusion that the aromatic ring of Phe20 stabilizes the polarization of the π-electron density induced by the oxidized iron in the same heme. Furthermore, the reduction potential of heme 2 was also affected by the mutation at Phe20, revealing that the electrostatic interaction between the π-electron system of the porphyrin and a distant iron contributes to the iron reduction potential. This kind of interaction provides new insight into the role of the heme architecture in regulation of the reduction potentials.</P>

Identification of T-cell receptor expression in EBV-positive neoplastic cells in extranodal NK/T-cell lymphoma, nasal-type, and comparison with T-cell receptor gene rearrangement by BIOMED-2 assay

Takayama, Takuya,Shin, Sohyun,Kang, SoYoung,Kim, Suk Jin,Kim, Won Seog,Ko, Young Hyeh Elsevier 2018 Human pathology Vol.73 No.-

<P>The cellular lineage of extranodal NK/T-cell lymphoma, nasal-type (ENKTL), is determined by expression of T-cell receptor (TR) or TR gene rearrangement. In ENKTL, from TR immunohistochemistry, it may often be difficult to decide whether TR-positive cells are tumor cells or not, especially when TR is expressed in a subset of tumor cells. To analyze TR expression pattern and TR rearrangement in T lineage ENKTL, we performed double immunofluorescence staining for Epstein-Barr virus encoded small RNAs (EBER)/T-cell receptor (TCR) beta F1 and CD56/TCR beta F1 in 12 cases of ENKTL that showed TCR beta F1 expression in immunohistochemistry. TR gene rearrangement was analyzed using a commercial BIOMED-2 multiplex polymerase chain reaction system. Immunohistochemistry showed that all 12 cases expressed TCR beta F1 in a wide range of infiltrating cells from 100% to <1%. Two of them expressed both TCR beta F1 and TCR c gamma M1. EBER/TCR-beta F1 positivity was confirmed in 10 cases by double staining. One case failed to show EBER/TCR-beta F1 positive cells but showed a CD56/TCR beta F1 positive result. Among 12 cases, 5 had poor-quality DNA, 3 of them showed no polymerase chain reaction product, and 2 cases showed nonspecific peak of low height. Five of 7 cases with good DNA quality demonstrated monoclonal TR gene rearrangement. Based on TR expression and TR gene rearrangement, 10 of 12 cases of ENKTL were decided as a T-lineage tumor. In conclusion, because of common TR silence and poor DNA quality, consideration of both immunohistochemistry and TR gene rearrangement is necessary to determine the lineage of ENKTL. (C) 2017 Elsevier Inc. All rights reserved.</P>

Fabrication of Semi-Artificial Cellulose Fiber Production System Using Cellulose Spinning Machinery of Bacteria

( Go Takayama ),( Shingo Yokota ),( Tetsuo Kondo ) 한국목재공학회 2021 한국목재공학회 학술발표논문집 Vol.2021 No.1

Nanocelluloses, which are produced by nano-downsizing processes of pulp fibers, have attracted much attention in recent years due to their excellent physical properties and specific surface characteristics. For material design using nanocelluloses, facile understanding of the relationship between structure and property is an essential issue. In contrast, as the 3D-stractural formation starting from biosynthesis of native nanocelluloses has been still complexed as a bottom-up mechanism, it prevents the control of their hierarchical structure in native systems including bacterial producing system. A model system of cellulose fiber spinning mechanism would contribute to the further understanding of the 3D-hierachical structure formation of nanocelluloses. Biosynthesis of native cellulose accompanied with polymerization and crystallization processes is well known to be achieved through synthetic enzyme complexes called Terminal Complexes (TCs). However, the following process including assembly of the nanofibrils secreted from cells has been still unclear, even though the combination of the biosynthesis and the following assembly process is of importance to establish the nano/micro fibrils of cellulose. Then, this unique process leads to the remarkable characteristics of native cellulose fibers. A cellulose-producing bacterium, Gluconacetobacter, has been extensively studied as a model-organism of the cellulose biosynthesis and there have been many studies on in vitro reconstruction of the cellulose synthesis activity. In this study, for the above goal, we first explored a method to extract intact TCs of Gluconacetobacter xylinus from the cell without outer cell walls, and then cellulose fiber spinning activity of the extracted TCs were examined to confirm the intact ability. Namely, bacteria (ATCC23769) were subjected to cell wall digestion treatment and then were burst by osmotic shock to obtain cell membrane fragments holding intact TCs. Finally, cellulose synthesis reaction was conducted using the burst cells.

A Novel Technique of Hand-Sewn Purse-String Suturing by Double Ligation Method (DLM) for Intracorporeal Circular Esophagojejunostomy

Yuichi Takayama,Yuji Kaneoka,Atsuyuki Maeda,Yasuyuki Fukami,Takamasa Takahashi,Masahito Uji 대한위암학회 2019 Journal of gastric cancer Vol.19 No.3

Purpose: The optimal method for intracorporeal esophagojejunostomy remains unclearbecause a purse-string suture for fixing the anvil into the esophagus is difficult to performwith a laparoscopic approach. Therefore, this study aimed to evaluate our novel technique tofix the anvil into the esophagus. Materials and Methods: This retrospective study included 202 patients who were treatedat our institution with an intracorporeal circular esophagojejunostomy in a laparoscopyassistedtotal gastrectomy with a Roux-en-Y reconstruction (166 cases) or a laparoscopyassistedproximal gastrectomy with jejunal interposition (36 cases). After incising 3/4 ofthe esophageal wall, a hand-sewn purse-string suture was placed on the esophagus. Next,the anvil head of a circular stapler was introduced into the esophagus. Finally, the circularesophagojejunostomy was performed laparoscopically. The clinical characteristics andsurgical outcomes were evaluated and compared with those of other methods. Results: The average operation time was 200.3 minutes. The average hand-sewn pursestringsuturing time was 6.4 minutes. The overall incidence of postoperative complications(Clavien–Dindo classification grade ≥II) was 26%. The number of patients with ananastomotic leakage and stenosis at the esophagojejunostomy site were 4 (2.0%) and 12(6.0%), respectively. All patients with stenosis were successfully treated by endoscopicballoon dilatation. There was no mortality. Regarding the materials and devices for anvilfixation, only 1 absorbable thread was needed. Conclusions: Our procedure for hand-sewn purse-string suturing with the double ligationmethod is simple and safe.

IMPROVEMENT OF DISTRIBUTION OF COERCIVITY IN CO-CR FILMS DEPOSSSITED BY FACING TARGETS SPUTTERING

Seiryu TAKAYAMA,Shigeki NAKAGAWA,Kyung-Hwan KIM,Masahiko NAOE 한국표면공학회 1996 한국표면공학회지 Vol.29 No.6

Special Lecture : Minimally invasive gynecological operations

( Masaomi Takayama ) 대한산부인과학회 1998 대한산부인과학회 학술대회 Vol.82 No.-

Mechanical properties of bio-absorbable PLA/PGA fiber-reinforced composites

Tetsuo Takayama,Youhei Daigaku,Hiroshi Ito,Hideki Takamori 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.10

This study investigated important mechanical properties, the flexural strength and flexural modulus, of polyglycolic acid (PGA) fiberreinforcedpolylactic acid (PLA) composites fabricated by melt-mixing. The flexural strength and flexural modulus were estimated usingthree-point bending tests conducted at 37°C. Both the flexural strength and flexural modulus were increased by PGA fiber reinforcement. Viscoelastic properties were also investigated using dynamic mechanical analysis (DMA) under tensile loading. Results show that PGAfiber, which acts as the nucleate agent of PLA, restrains the molecular chains of PLA. That restraint reduces deformation at the samestress condition, thereby improving the PLA flexural properties.

High-Throughput 3D MicroPhysiological Systems

Shuichi TAKAYAMA 한국생물공학회 2022 한국생물공학회 학술대회 Vol.2022 No.9

Numerical analysis of multi-parallelized swirling flow inside a circular pipe

Akimasa Takayama,Koki Kitagawa,Toru Shimada 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.3

The flow field of multi-parallelized swirling flow inside a circular pipe was investigated numerically. Two types of swirling flow configurationare considered. One type is the co-rotating type. Four co-rotating swirls are arranged at the vertex position of square in thistype. The other type is the counter-rotating type which consists of two pairs of swirls having opposite swirl rotations. Each pair is arrangeddiagonally at the vertex position of a square. By coupling the discrete vortex method and boundary element method, unsteadyflow simulation is performed. Swirl modeling with vortex elements is used in this simulation and its validity is confirmed. From thesimulation results, in the co-rotating type, the four swirls interact and their shape is deformed. Each vortex motion vanishes rapidly in thedownstream region. Finally, they are turned into a single swirling flow. In counter-rotating type, each vortex motion is maintained a littlebit longer than co-rotating type, and their shape is not so deformed. However, the flow patterns are changed completely in the downstreamregion. The swirling velocity of each swirl mostly vanishes. Finally, they are turned into an axial flow. For the investigation of themixing promoting effect due to parallelizing swirls, particle tracking simulations are performed in the co-rotating type and the counterrotatingtype. As a comparison, the simulation for single swirl flow is also performed. In these simulations, the particles are introduced inthe vicinity of pipe inner wall. In addition, the assumption that particles follow the flow motion absolutely is used. From the results, themotion of particles in these three cases is completely different. For the co-rotating and counter-rotating type, the particle entrainment intothe main axial flow is clearly observed. This indicates the mixing is improved compared to single swirl flow. The difference of particleentrainment motion between co-rotating and counter-rotating type is slight.