http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Akihisa Ohno,Nao Fujimori,Toyoma Kaku,Masayuki Hijioka,Ken Kawabe,Naohiko Harada,Makoto Nakamuta,Takamasa Oono,Yoshihiro Ogawa 대한소화기내시경학회 2022 Clinical Endoscopy Vol.55 No.6
Background/Aims: Patients with acute cholecystitis (AC) after metallic stent (MS) placement for malignant biliary obstruction (MBO)have a high surgical risk. We performed percutaneous transhepatic gallbladder aspiration (PTGBA) as the first treatment for AC. Weaimed to identify the risk factors for AC after MS placement and the poor response factors of PTGBA. Methods: We enrolled 401 patients who underwent MS placement for MBO between April 2011 and March 2020. The incidence of ACwas 10.7%. Of these 43 patients, 37 underwent PTGBA as the first treatment. The patients’ responses to PTGBA were divided into goodand poor response groups. Results: There were 20 patients in good response group and 17 patients in poor response group. Risk factors for cholecystitis after MSplacement included cystic duct obstruction (p<0.001) and covered MS (p<0.001). Cystic duct obstruction (p=0.003) and uncovered MS(p=0.011) demonstrated significantly poor responses to PTGBA. Cystic duct obstruction is a risk factor for cholecystitis and poor re-sponse factor for PTGBA, whereas covered MS is a risk factor for cholecystitis and an uncovered MS is a poor response factor of PTG-BA for cholecystitis. Conclusions: The onset and poor response factors of AC after MS placement were different between covered and uncovered MS. PTG-BA can be a viable option for AC after MS placement, especially in patients with covered MS.
Akihisa Otaka,Yasuhiko Iwasaki 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.75 No.-
Phosphorus-containing polymers are taking a growing interest as a bio-applicable material. Anionic poly(phosphodiester) is one type of phosphorus-containing polymer and has a similar backbone structure toteichoic acid (TA), which makes up the cell walls of gram-positive bacteria. In this study, we synthesized acopolymer of ethylene sodium phosphate and butynyl phosphate (P(EP Na/BYP)), which mimics TA and,thus, should be taken up by macrophages by the same mechanism as bacterial cells. In-vitro studiesshowed that RAW 264.7 mammalian macrophages exhibited higher uptake of P(EP Na/BYP) than L929mammalianfibroblasts. Further, the uptake of P(EP Na/BYP) by macrophages decreased in the presence ofdextran sulfate; this implies that the scavenger receptor contributes to endocytosis of P(EP Na/BYP). Invitrostudies on P(EP Na/BYP) with different lengths (38, 85, and 127 phosphate residues) showed that P(EP Na/BYP) with 127 phosphate residues led to the highest intracellular transportation and the leastgene expressions of IL-6 and TNF-α. These results demonstrate that water-soluble poly(phosphodiester)can be used as a modifier to deliver medical drugs to macrophages.
Network Technologies for IMT-2000
Akihisa Nakajima 에스케이텔레콤 (주) 1997 Telecommunications Review Vol.7 No.4
In Japan, the number of cellular subscribers is growing explosively. This will result in a radio bandwidth shortage by the year 2000. Also, mobile data communications have been growing as an essential service in society. To overcome the insufficient network capacity and realize multimedia services, NTT DoCoMo is carrying out network development for International Mobile Telecommunications 2000 (IMT-2000), formerly known as Future Public Land Mobile Telecommunication Systems (FPLMTS) [1],[2]. To realize the IMT-2000 network, a number of studies and standardization activities are being carried out in diverse areas. Functional network models and reference models, an ATM transmission technique for asymmetrically handling data at a wide range of speeds, including low-bit-rate mobile voice data, and signalling protocols supporting various services, are being discussed and standardized. This paper clarifies requirements and introduces these network technologies for use in the IMT-2000 network.
Synthetic Study of Carbohydrate Binding Domain of Siglec7
Akihisa Otsuki,Ryo Okamoto,Masayuki Izumi,Yasuhiro Kajihara 한국당과학회 2012 한국당과학회 학술대회 Vol.2012 No.1
Sialic acid-binding immunoglobulin-like lectin (Siglec) 7 is one of the sialic acid binding protein that plays an important role in immune system. Siglec 7 is expressed on natural killer cells and displays a unique ligand binding properties comparing to the other members of the Siglec family, specifically binds to 2,8-disialyl residues. The precise structural analysis of Siglec 7 has been already performed, and amino acid residues involved in the ligand binding are reported. In such context, we set out the first total chemical synthesis of Siglec 7 carbohydrate binding domain (CBD) which consists of 127 amino acid residues. Since chemical synthesis can easily introduce unnatural amino acids, we envisioned that we could produce an artificial sialic acid binding lectin based on this chemical synthetic strategy. The synthesis of Siglec 7 CBD was carried out by convergent total chemical synthesis. The whole polypeptide was assembled from 5 peptide segments (Figure), which were synthesized by conventional solid phase peptide synthesis. We applied native chemical ligation (NCL) for the coupling of these segments sequentially from C-terminus, combined with alkylation with haloacetoamide or desulfuration reaction. These reactions can provide pseudo-Gln residue or Ala residue from Cys residues at the ligation sites. Based on these strategies we have successfully obtained the full-length polypeptide of Siglec 7 CBD and currently are investigating the in vitro folding step.