강연 7

( Fumitaka Tsukihashi ) 대한금속재료학회 ( 구 대한금속학회 ) 1999 대한금속학회 추계학술대회 개요집 Vol.1999 No.-

Uranium Particle Identification with SEM-EDX for Isotopic Analysis by Secondary Ion Mass Spectrometry

( Fumitaka Esaka ),( Masaaki Magara ) 한국질량분석학회 2016 Mass spectrometry letters Vol.7 No.2

Secondary ion mass spectrometry (SIMS) is a promising tool to measure isotope ratios of individual uranium particles in environmental samples for nuclear safeguards. However, the analysis requires prior identification of a small number of uranium particles that coexist with a large number of other particles without uranium. In the present study, this identification was performed by scanning electron microscopy - energy dispersive X ray analysis with automated particle search mode. The analytical results for an environmental sample taken at a nuclear facility indicated that the observation of backscattered electron images with × 1000 magnification was appropriate to efficiently identify uranium particles. Lower magnification (less than × 500) made it difficult to detect smaller particles of approximately 1 μm diameter. After identification, each particle was manipulated and transferred for subsequent isotope ratio analysis by SIMS. Consequently, the isotope ratios of individual uranium particles were successfully determined without any molecular ion interference. It was demonstrated that the proposed technique provides a powerful tool to measure individual particles not only for nuclear safeguards but also for environmental sciences.

Characterization of Fruit Maturity and Fruit Sugar Accumulation in ‘Harumi’ Mandarin

Fumitaka Takishita,Kiyoshi Hiraoka,Noboru Muramatsu,Makoto Uchida 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

SOUND POWER LEVELS OF MUSICAL INSTRUMENTS AND THE ESTIMATION OF THE INFLUENCE ON PLAYERS’ HEARING ABILITY

Fumitaka Saito,Makiko Kasuya,Toshio Harima,Yoiti Suzuki 한국소음진동공학회 2003 한국소음진동공학회 국제학술대회논문집 Vol.2003 No.8

Precise spectral analysis using a multiple band-pass filter for flash-visual evoked potentials

( Fumitaka Asano ),( Ichiro Shimoyama ),( Yasufumi Kasagi ),( Alex Lopez ) 한국감성과학회 2002 춘계학술대회 Vol.2002 No.-

The fast Fourier transform (FFT) is a good method to estimate spectral density, but the frequency resolution is limited to the sampling window, and thus the precise characteristics of the spectral density for short signals are not clear. To solve the limitation, a multiple band-pass filter was introduced to estimate the precise time course of the spectral density for flash visual evoked potentials (VEPs). Signals were recorded during -200 and 600 ms using balanced noncephalic electrodes, and sampled at 1 K Hz in 12 bits. With 1 Hz and 10 ms resolutions, spectral density was estimated between 10 and 100 Hz. Background powers at the alpha-and beta-bands were high over the posterior scalp, and powers around 200ms were evoked at the same bands over the same region, corresponding to P110 and N165 of VEPs. normalized``s spectral density showed evoked powers around 200 ms and suppressed powers following the evoked powers over the posterior scalp. The evoked powers above the 20Hz band were not statistically significant. However, the gamma band was significantly evoked intra-individually; details in the gamma bands were varied among the subjects. Details of spectral density were complicated even for a simple task such as watching flashes; both synchronization and desynchronization occurred with different distributions and different time courses.

Feasibility Study of Isotope Ratio Analysis of Individual Uranium-Plutonium Mixed Oxide Particles with SIMS and ICP-MS

( Fumitaka Esaka ),( Masaaki Magara ),( Daisuke Suzuki ),( Yutaka Miyamoto ),( Chi-gyu Lee ),( Takaumi Kimura ) 한국질량분석학회 2011 Mass spectrometry letters Vol.2 No.4

Isotope ratio analysis of nuclear materials in individual particles is of great importance for nuclear safeguards. Although secondary ion mass spectrometry (SIMS) and thermal ionization mass spectrometry (TIMS) are utilized for the analysis of individual uranium particles, few studies were conducted for the analysis of individual uranium-plutonium mixed oxide particles. In this study, we applied SIMS and inductively coupled plasma mass spectrometry (ICP-MS) to the isotope ratio analysis of individual U-Pu mixed oxide particles. In the analysis of individual U-Pu particles prepared from mixed solution of uranium and plutonium standard reference materials, accurate 235U/238U, 240Pu/239Pu and 242Pu/239Pu isotope ratios were obtained with both methods. However, accurate analysis of 241Pu/239Pu isotope ratio was impossible, due to the interference of the 241Am peak to the 241Pu peak. In addition, it was indicated that the interference of the 238UH peak to the 239Pu peak has a possibility to prevent accurate analysis of plutonium isotope ratios. These problems would be avoided by a combination of ICP-MS and chemical separation of uranium, plutonium and americium in individual U-Pu particles.

Treatment of hepatitis C with direct-acting antiviral agents: Japanese experience

( Fumitaka Suzuki ),( Hiromitsu Kumada ) 대한간학회 2012 춘·추계 학술대회 (KASL) Vol.2012 No.1

In Japan, an estimated 100-150 million people are persistently infected with hepatitis C virus (HCV). The present standard-of-care (SOC) therapy for patients infected with HCV of genotype 1b, the most prevalent genotype in Japan, is peginterferon (PEG-IFN) combined with ribavirin (RBV) for 48 weeks. However, sustained virological response (SVR), judged by the loss of detectable HCV RNA from serum 24 weeks after the completion of therapy, can be achieved in only 42?52% of the patients. To cope with this grim situation, a number of direct acting antivirals (DAAs) have been designed and developed, represented by NS3/4A protease inhibitors and NS5B polymerase or NS5A inhibitors. Among them, telaprevir (TVR) has shown promising results, when combined with PEG-IFN and RBV, in the phase 2 and 3 clinical trials, by improving SVR to ~70% in patients infected with HCV-1. Moreover, the triple therapy with TVR, PEG-IFN, and RBV for 12 weeks, followed by PEG-IFN and RBV for an additional 12 weeks (T12PR24) were reimbursed since November 2011 in Japan. In Japanese clinical studies (phase III, T12PR24), the SVR rates of naive, relapse and non-responder were 73% (92/126), 88% (96/109) and 35% (11/32). We investigate the predictive factors of SVR to a 12-week or 24-week regimen of triple therapy in 81 Japanese patients infected with HCV genotype 1. SVR was achieved by 45% and 67% in the 12- and 24 week regimens, respectively. Multivariate analysis identified rs8099917 near the IL28B gene (genotype TT) and substitution at aa 70 (Arg70) as significant determinants of SVR. Prediction of response to therapy based on a combination of these factors had high sensitivity, specificity, and positive and negative predictive values. The efficacy of triple therapy was high in the patients with genotype TT, who accomplished SVR (85%), irrespective of substitution of core aa 70. In the patients having genotype non-TT, those of Arg70 gained high SVR (57%), and SVR (17%) was the worst in patients who possessed both genotype non-TT and Gln70 (His70). Important adverse events were anemia and shin disorder (mainly rash, drug eruptions, and erythema). Next, dual oral therapy with the NS5A inhibitor (daclatasvir) and NS3 protease inhibitor (asunaprevir) in HCV genotype 1b-infected null responders or patients ineligible or intolerant to peginterferon/ribavirin were done (phase II) in Japan. This study (AI447-017) enrolled two populations infected with HCV genotype 1, including null responders and patients intolerant or medically ineligible to PEG-IFN and RBV. The overall SVR rate was 77%. A higher SVR rate was observed in the null responders (91%) compared to the ineligible and intolerant patients (64%). The overall response to therapy was not influenced by IL28B genotype. Potential association between virologic failure and pre-existing NS5A polymorphisms and low plasma concentrations of asunaprevir and daclatasvir requires further study.

Treatment of hepatitis C with direct-acting antiviral agents: Japanese experience

( Fumitaka Suzuki ),( Hiromitsu Kumada ) 대한간학회 2012 춘·추계 학술대회 (KASL) Vol.2012 No.-

In Japan, an estimated 100-150 million people are persistently infected with hepatitis C virus (HCV). The present standard-of-care (SOC) therapy for patients infected with HCV of genotype 1b, the most prevalent genotype in Japan, is peginterferon (PEG-IFN) combined with ribavirin (RBV) for 48 weeks. However, sustained virological response (SVR), judged by the loss of detectable HCV RNA from serum 24 weeks after the completion of therapy, can be achieved in only 42-52% of the patients. To cope with this grim situation, a number of direct acting antivirals (DAAs) have been designed and developed, represented by NS3/4A protease inhibitors and NS5B polymerase or NS5A inhibitors. Among them, telaprevir (TVR) has shown promising results, when combined with PEG-IFN and RBV, in the phase 2 and 3 clinical trials, by improving SVR to ~70% in patients infected with HCV-1. Moreover, the triple therapy with TVR, PEG-IFN, and RBV for 12 weeks, followed by PEG-IFN and RBV for an additional 12 weeks (T12PR24) were reimbursed since November 2011 in Japan. In Japanese clinical studies (phase III, T12PR24), the SVR rates of naive, relapse and non-responder were 73% (92/126), 88% (96/109) and 35% (11/32). We investigate the predictive factors of SVR to a 12-week or 24-week regimen of triple therapy in 81 Japanese patients infected with HCV genotype 1. SVR was achieved by 45% and 67% in the 12- and 24-week regimens, respectively. Multivariate analysis identified rs8099917 near the IL28B gene (genotype TT) and substitution at aa 70 (Arg70) as significant determinants of SVR. Prediction of response to therapy based on a combination of these factors had high sensitivity, specificity, and positive and negative predictive values. The efficacy of triple therapy was high in the patients with genotype TT, who accomplished SVR (85%), irrespective of substitution of core aa 70. In the patients having genotype non-TT, those of Arg70 gained high SVR (57%), and SVR (17%) was the worst in patients who possessed both genotype non-TT and Gln70 (His70). Important adverse events were anemia and shin disorder (mainly rash, drug eruptions, and erythema). Next, dual oral therapy with the NS5A inhibitor (daclatasvir) and NS3 protease inhibitor (asunaprevir) in HCV genotype 1b-infected null responders or patients ineligible or intolerant to peginterferon/ribavirin were done (phase II) in Japan. This study (AI447-017) enrolled two populations infected with HCV genotype 1, including null responders and patients intolerant or medically ineligible to PEG-IFN and RBV. The overall SVR rate was 77%. A higher SVR rate was observed in the null responders (91%) compared to the ineligible and intolerant patients (64%). The overall response to therapy was not influenced by IL28B genotype. Potential association between virologic failure and pre-existing NS5A polymorphisms and low plasma concentrations of asunaprevir and daclatasvir requires further study.

The mutual contribution of estrogen and PTEN mutations to endometrial carcinogenesis

( Fumitaka. Saito ) 대한산부인과학회 2007 대한산부인과학회 학술대회 Vol.93 No.-

Post Marketing Surveillance of Daclatasvir/Asunaprevir in Japanese Patients with Chronic Hepatitis C: An Interim Report

( Fumitaka Suzuki ),( Naoya Hatanaka ),( Etsuya Bando ),( Akira Komoto ) 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Aims: Daclatasvir (DCV) combined with asunaprevir (ASV) was the first all-oral treatment to be approved in Japan for chronic hepatitis C virus (HCV) serogroup 1 infection in patients with/without compensated cirrhosis. We report interim findings of a post-marketing survey of DCV+ASV in Japanese patients treated in the routine clinical setting. Methods: The survey aimed to register a total of 3000 HCV-infected patients, including 1000 patients with compensated cirrhosis, between September 2014 and August 2015. All patients received oral DCV 60mg once daily + ASV 100 mg twice daily for 24 weeks. This report includes safety data collected up to 3 July 2016. Results: Of the 3089 patients registered, 2165 (70.0%) patients (female, n=1233 [57.0%]; mean age, 69.1 years [range: 21-92]; compensated cirrhosis, n=862 [39.8%]) are included in the safety set; 1874 (86.6%) patients have completed the treatment period. The main reasons for discontinuation in the safety set were adverse events (n=146 [6.7%]) and lack of efficacy (n=86 [4.0%]). A total of 538 patients (24.85%) in the safety set experienced a total of 811 adverse drug reactions (ADRs). Events corresponding to the composite ADR term ‘hepatic function disorder’ occurred in 315 patients (14.55%). Common ADRs were: hepatic function abnormal (n=133 [6.14%]), increased eosinophil count (n=67 [3.09%]), increased alanine aminotransferase (n=63 [2.91%]), increased aspartate aminotransferase (n=61 [2.82%]), liver disorder (n=58 [2.68%]) and pyrexia (n=53 [2.45%]); rates of ADRs in patients with/without compensated cirrhosis were generally comparable (Table). Serious ADRs which occurred in two or more patients were liver disorder (n=5 [0.23%]), pyrexia (n=4 [0.18%]); hepatic function abnormal (n=3 [0.14%]) hepatic hepatic encephalopathy (n=2 [0.09%]) and jaundice (n=2 [0.09%]); all serious ADRs have/are resolved/resolving and all patients have/are recovered/recovering. No deaths have been reported. Conclusions: DCV + ASV was generally well tolerated in this interim analysis of real-world data.