탄도미사일방위의 국제법 및 자위권행사에 관한 법적 제문제

Takai, Susumu 한국항공우주법학회 2000 한국항공우주정책·법학회지 Vol.12 No.-

Bufalin, a Traditional Oriental Medicine, Induces Apoptosis in Human Cancer Cells

Takai, Noriyuki,Kira, Naoko,Ishii, Terukazu,Yoshida, Toshie,Nishida, Masakazu,Nishida, Yoshihiro,Nasu, Kaei,Narahara, Hisashi Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Bufalin is a traditional oriental medicines which induces apoptosis in some lines of human tumor cells. It constitutes the major digoxin-like immunoreactive component of Chan Su, obtained from the skin and parotid venom glands of toads. Bufalin is cardioactive C-24 steroids that exhibits a variety of biological activities, such as cardiotonic, anaesthetic, blood pressure stimulatory, respiratory and antineoplastic effects. In terms of its anti-tumor activity, bufalin has been demonstrated to inhibit the growth of tumors, such as endometrial and ovarian cancers. This commentary introduces biologic and therapeutic effects of bufalin in treating some cancers. The compound is able to mediate inhibition of cell growth, cell cycle arrest, apoptosis, and expression of genes related to the malignant phenotype in human cancer cells.

Feasibility of Photodynamic Diagnosis for Challenging TUR-Bt Cases Including Muscle Invasive Bladder Cancer, BCG Failure or 2^nd-TUR

Takai, Tomoaki,Inamoto, Teruo,Komura, Kazumasa,Yoshikawa, Yuki,Uchimoto, Taizo,Saito, Kenkichi,Tanda, Naoki,Kouno, Junko,Minami, Koichiro,Uehara, Hirofumi,Takahara, Kiyoshi,Hirano, Hajime,Nomi, Hayahi Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Background: Despite widely adopted standard methods for follow-up including cystoscopy plus cytology, recurrence rates of non muscle-invasive bladder cancer (NMIBC) have not improved over the past decades, still ranging from 60% through 70%. Hence, widely acceptable surveillance strategies with excellent sensitivity are needed. Early recurrence has led to the development of a novel cystoscopy technique utilizing photodynamic diagnosis (PDD). Although, no studies have evaluated the efficacy of PDD for patients of MIBC, BCG failure or 2nd-transurethelial resection (TUR). Materials and Methods: The present study was performed from October 2012 through May 2013. IRB approved 25 patients initially underwent a cystoscopy examination of white light and blue light followed by the resection of tumors identified. Resections were performed from bladder mucosa areas considered suspicious at PDD, along with PDD negative normal bladder mucosa area resected by random biopsy. Specimens were divided into two groups, PDD positive and negative. Primary endpoints were sensitivity and specificity. Results: A total of 147 specimens extracted from 25 patients were included in the analysis. Some 45 out of 92 PDD-positive specimens were confirmed to have bladder cancer, and 51 out of PDD-negative 55 specimens were confirmed to be cancer negative. The sensitivity of PDD was 91.8% (45/49) and specificity was 52.0% (51/98). The sensitivity:specificity was 89.5% (17/19) : 47.6% (30/63) in 12 2nd-TUR patients, 90.5% (19/21) : 61.1% (11/18) in seven MIBC patients, and 95.0% (19/20) : 48.5% (16/33) in eight failed BCG cases. Conclusions: PDD-TURBT has high sensitivity to diagnose BC even for 2nd-TUR, MIBC or BCG failure cases.

Facile formation of a <i>meso</i>–<i>meso</i> linked porphyrin dimer catalyzed by a manganese(<small>IV</small>)–oxo porphyrin

Takai, Atsuro,Habermeyer, Benoit,Fukuzumi, Shunichi Royal Society of Chemistry 2011 Chemical communications Vol.47 No.24

<P>A manganese(<SMALL>IV</SMALL>)–oxo porphyrin catalyzes C–C bond formation between zinc porphyrins at the <I>meso</I>-position with a two-electron oxidant to afford the <I>meso</I>–<I>meso</I> linked porphyrin dimer efficiently. The <I>meso</I>–<I>meso</I> linked dimer is formed <I>via</I> formation of the porphyrin radical cation, and the rate-determining step in the catalytic cycle is the formation of a manganese(<SMALL>IV</SMALL>)–oxo porphyrin with a two-electron oxidant.</P> <P>Graphic Abstract</P><P>A manganese(<SMALL>IV</SMALL>)–oxo porphyrin catalyzes C–C bond formation between zinc porphyrins to afford the <I>meso</I>–<I>meso</I> linked dimer efficiently. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1cc10608b'> </P>

Response characteristics and suppression of torsional vibration of rectangular prisms with various width-to-depth ratios

Takai, Kazunori,Sakamoto, Hiroshi Techno-Press 2006 Wind and Structures, An International Journal (WAS Vol.9 No.1

The response characteristics and suppression of flow-induced vibrations of rectangular prisms with various width-to-depth ratios were experimentally investigated. The prisms were rigid and elastically mounted at both ends to enable constrained torsional vibrations only. The present study focused on torsional vibrations, one of the three types of flow-induced vibrations generated in a rectangular prism. First, the response characteristics of torsional vibrations generated in rectangular prisms were investigated by free-vibration tests. It was found that the response characteristics of torsional vibrations generated in rectangular prisms could be classified into six patterns depending on the width-to-depth ratio. Next, the response characteristics of torsional vibrations observed in the free-vibration tests were reproduced by forced-vibration tests, and the mechanisms by which the three types of flow-induced vibrations, low-speed torsional flutter, vortex excitation and high-speed torsional flutter, are generated in the rectangular prisms were elucidated on the basis of characteristics of fluid forces and visualized flow patterns. Experiments were also carried out to establish an effective method for suppressing flow-induced vibrations generated in the rectangular prisms, and it was found that low-speed torsional flutter and high-speed torsional flutter could be suppressed by placing a small normal plate upstream of the prism, which results in suppression of the alternating rolling-up of the shear layers separating from the leading edges of the prism. It was also found that vortex excitation could be suppressed by placing a splitter plate downstream of the prism, which results in suppression of the generation of wake vortices.

Prostatic Bleeding after Prostatic Biopsy Effects Oncological Outcomes with Laparoscopic Radical Prostatectomy

Takai, Tomoaki,Inamoto, Teruo,Komura, Kazumasa,Tsujino, Takuya,Matsunaga, Tomohisa,Yoshikawa, Yuki,Uchimoto, Taizo,Saito, Kenkichi,Tanda, Naoki,Minami, Koichiro,Uehara, Hirofumi,Ibuki, Naokazu,Takahar Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

Background: We vigorously reviewed patients' operation record who had adhesion of the Denonvilliers' fascia and found out most of these patients had prostatic bleeding after prostatic gland biopsies. We examined the magnitude of prostatic bleeding and frequency after biopsies and the relationship with oncological outcomes. Materials and Methods: A total of 285 patients were selected for the final analyses. Inclusion criteria were as follows: receiving MRI three weeks after biopsiesand laparoscopic radical prostatectomy within 300 days after biopsy. We divided the patients into two groups with (group A) or without (group B) prostatic bleeding. We examined the magnitude of prostatic bleeding after biopsies and the relationship with operation time (OT), positive surgical margin (PSM), biochemical recurrence (BCR) and other factors. Furthermore, we created a logistic-regression model to derive a propensity score for prostatic bleeding after biopsies, which included all patient and hospital characteristics as well as selected interaction terms, and we examined the relationship with PSM and BCR. Results: In all patients, the OT in the group B was shorter than the group A (p < 0.001). Prostatic bleeding was associated with PSM (p=0.000) and BCR (p=0.036). In this propensity-matched cohort, 11 of 116 patients in the group B had PSM as compared with 36 of 116 patients from group A (match-adjusted odds ratio, 4.30; 95%CI confidence interval, 2.06 to 8.96; P=0.000). In addition, eight of 116 patients in group B encountered BCR, as compared with 18 of 116 patients in group A (match-adjusted odds ratio, 2.48; 95%CI, 1.03 to 5.96; P=0.042). Kaplan-Meier analysis in the propensity matching cohort showed a significant biochemical recurrence-free survival advantage for being free of prostate bleeding after biopsies. Conclusions: Our findings in the present cohort should help equip surgeons to pay attention to careful excision especially for those who experienced deferred prostatic bleeding.

"Peaceful Uses" of Outer Space and Japan' s Space Policy

Takai, Susumu Korea Society of Air Space Law and Policy 2007 한국항공우주정책·법학회지 Vol.2007 No.special

Space development and utilization must be conducted within a framework of "peaceful uses" principle under Space Treaty. Japan ratified the treaty in 1967, and interpreted "peaceful uses" as "non-military uses" then. A ghost of "peaceful uses" principle has been hung over Japan up to the moment. Japan's space development and utilization has been conducted with genuine academic interest, and therefore Japan did not introduce space infrastructures to national security policy and did not facilitate growth of space industry. When the Cold War ended, Northeast Asian security environment makes Japan difficult to maintain an interpretation as "non-military uses". Besides the change of external security environment, the domestic industry situation and a series of rocket launching failure needed reexamination of Japan's space policy. Japan is gradually changing its space policy, and introducing space infrastructure in a national security policy under a "generalization" theory that gave a broad interpretation of "peaceful uses" principle. Council for Science and Technology Policy (CSTP) adopted a basic strategy of Japan's space policy in 2004. Since then, a long-term report of Japan Aerospace Exploration Agency (JAXA), an investigation report of Society of Japanese Aerospace Companies (SJAC) and a proposal of Japan Business Federation (JSF) were followed. Japan will promote space development and utilization in national security policy with a "strictly defensive defense" strategy and "non-aggressive uses"principle for protection of life and property of Japanese people and stabilization of East Asian countries.

Microbial Dynamics of Paddy Soil Under Waterlogged Condition

Takai, Yasuo 한국토양비료학회 1984 한국토양비료학회지 Vol.17 No.3

Efficient Photoinduced Electron Transfer in a Porphyrin Tripod−Fullerene Supramolecular Complex via π−π Interactions in Nonpolar Media

Takai, Atsuro,Chkounda, Mohammed,Eggenspiller, Antoine,Gros, Claude P.,Lachkar, Mohammed,Barbe, Jean-Michel,Fukuzumi, Shunichi American Chemical Society 2010 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.132 No.12

<P>A novel porphyrin tripod (TPZn<SUB>3</SUB>) was synthesized via “click chemistry”. Three porphyrin moieties of TPZn<SUB>3</SUB> are geometrically close and linked by a flexible linker. The electron-transfer oxidation of TPZn<SUB>3</SUB> results in intramolecular π-dimer formation between porphyrin moieties as indicated by electrochemical, vis−NIR, and ESR measurements. The cyclic voltammogram of TPZn<SUB>3</SUB> exhibited stepwise one-electron oxidation processes of three porphyrin moieties in the range from 0.58 to 0.73 V (vs SCE in CH<SUB>2</SUB>Cl<SUB>2</SUB>). When TPZn<SUB>3</SUB> was oxidized by tris(2,2′-bipyridyl)-ruthenium(III) ([Ru(bpy)<SUB>3</SUB>]<SUP>3+</SUP>), the oxidized species (TPZn<SUB>3</SUB>)<SUP><I>n</I>+</SUP> (0 < <I>n</I> ≤ 3) exhibited a charge resonance band in the NIR region due to the π-dimer formation between porphyrin moieties. A supramolecular electron donor−acceptor system was also constructed using TPZn<SUB>3</SUB>. The flexible conformation of TPZn<SUB>3</SUB> makes it possible to capture a fullerene derivative containing a pyridine moiety (PyC<SUB>60</SUB>) inside the cavity by π−π interactions as well as the coordination bond between Zn<SUP>2+</SUP> and the pyridine moiety. The formation of a 1:1 supramolecular complex of TPZn<SUB>3</SUB> with PyC<SUB>60</SUB> (TPZn<SUB>3</SUB>−PyC<SUB>60</SUB>) was indicated in the UV−vis and <SUP>1</SUP>H NMR spectra in nonpolar solvents. The association constant of TPZn<SUB>3</SUB> with PyC<SUB>60</SUB> (1.1 × 10<SUP>5</SUP> M<SUP>−1</SUP> in toluene) is much larger as compared with those of the corresponding monomer (MPZn) and dimer porphyrin (DPZn<SUB>2</SUB>). The dynamics of photoinduced electron transfer from the singlet excited state of TPZn<SUB>3</SUB> to PyC<SUB>60</SUB> was examined by laser flash photolysis measurements. The efficient intracomplex photoinduced electron transfer in TPZn<SUB>3</SUB>−PyC<SUB>60</SUB> occurred in nonpolar solvents, resulting from the π−π interactions between the porphyrin and fullerene moieties, together with intramolecular π-bond formation between the porphyrin radical cation and the neutral porphyrin in TPZn<SUB>3</SUB><SUP>•+</SUP>.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2010/jacsat.2010.132.issue-12/ja100192x/production/images/medium/ja-2010-00192x_0019.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja100192x'>ACS Electronic Supporting Info</A></P>

Oocyte aging and assisted reproduction

( Yasushi Takai ) 대한산부인과학회 2016 대한산부인과학회 학술대회 Vol.102 No.-

In recent years in Japan, more than 40,000 children are born each year by assisted reproduction, but the assisted reproduction registry of Japan Society of Gynecology and Obstetrics (JSOG) shows that the pregnancy rate decreases and the miscarriage rate increases in the women 35 years of age or older. This is assumed to be caused by a decrease in both the quantity and quality of the oocytes, and the age-related decrease of the oocyte quality is called as “oocyte aging” and draws increasing attention. Aged oocytes display increased chromosomal abnormality and dysfunction of cellular organelles, both of which are related with oocyte quality. In particular, mitochondrial dysfunction has been suggested as a major contributor to “oocyte aging”, but details of the mitochondrial dysfunction are still unknown. Various strategies in assisted reproduction have been tried for oocyte aging. In Japan, mild stimulation using clomiphene and letrozole has been widely performed for aged women, and several tips may be available, but its results are still unsatisfactory. The additional strategies are oocyte cryopreservation, oocyte donation, and oogonial stem cells. Randomized controlled trials comparing outcomes with cryopreserved and fresh oocytes in IVF/ICSI cycles showed that there were no significant differences in fertilization rates, implantation rates and pregnancy rates, but they also showed that the pregnancy rate decreased along with the ageing of women from whom the oocytes had been retrieved. Therefore, some ART clinics in Japan have started elective oocyte cryopreservation for unmarried young women, and Japan Society for Reproductive Medicine (JSRM) issued a guideline for elective oocyte cryopreservation which recommends oocyte pick up and cryopreservation under 40 years of age and utilization of cryopreserved oocytes under 45 years of age. Recent studies in Japan reported that more than 80% of patients with premature ovarian insufficiency and more than 40% of infertility patients have a positive view on oocyte donation. JSOG and JSRM have issued guidelines in 2004 and 2009, respectively, and both state that commercial egg donation should be prohibited, and only “altruistic” donation should be permitted. Although some ART clinics in Japan have started oocyte donation programs under strict regulation, most of oocyte donations for Japanese patients are assumed to be performed in foreign countries, which may burden perinatal centers in Japan. Recent studies describe the successful isolation and characterization of oogonial stem cells (OSCs) from ovarian cortical tissue of women. Although much is still to be learned about human OSCs from both basic science and clinical perspectives, application of human OSCs may be one of the strategies for oocyte aging. In the late 1990s, it was reported that transfer of a small amount of ooplasm from donor eggs of young women into eggs of women with a history of repeat IVF failure resulted in a remarkably high rate of IVF success, but heterologous ooplasmic transfer was quickly stopped by the US Food and Drug Administration because mitochondrial transfer represented an example of genetic manipulation of human germ cells for the purpose of reproduction. However, the delivery of autologous OSC-derived mitochondria into human oocytes during intracytoplasmic sperm injection (ICSI) may provide the energy boost needed to overcome existing mitochondrial deficits due to aging or other factors that negatively affect either fertilization outcome or embryonic competency.