著者
Mariko Kimoto Toshiyasu Sakane Hidemasa Katsumi Akira Yamamoto
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.70, no.2, pp.138-145, 2022-02-01 (Released:2022-02-01)
参考文献数
25
被引用文献数
1

The dissolution behaviors of base excipients from sustained-release formulations have been investigated using various methodologies. However, the dissolution of polymers has not been fully evaluated because differences between formulations are still verified only by the release of active pharmaceutical ingredients (APIs). In our previous study, we proposed a quick and simultaneous analysis of dissolved APIs and water-soluble polymers by ultra HPLC using charged aerosol and photodiode array detectors. The purpose of this study was to verify whether the analysis system could be adapted to other water-soluble polymers. Dissolution tests were conducted using matrix model tablets prepared from three polymers and three APIs (propranolol, ranitidine, and cilostazol) with different solubilities. The dissolution profiles of the polymers and APIs were determined using the proposed analysis system and compared. The results clarified differences in the dissolution behaviors of the APIs and polymers. The polymers, especially hydroxypropyl cellulose, exhibited the dissolution properties characteristic of each model formulation. Propranolol and ranitidine showed the diffusion type, while cilostazol showed the erosion type release mechanism due to their different solubilities. The release of cilostazol was delayed in all models compared to the polymer, which may be due to the aggregation of cilostazol in the gel layer. This analytical method can be used to study the dissolution behavior (diffusion or erosion) of APIs from matrix tablets containing various polymers. This method will provide useful information on release control, which will make it easier and more efficient to design appropriate formulations and analyze the release mechanisms.
著者
Hidenori Arai Akira Yamamoto Yuji Matsuzawa Yasushi Saito Nobuhiro Yamada Shinichi Oikawa Hiroshi Mabuchi Tamio Teramoto Jun Sasaki Noriaki Nakaya Hiroshige Itakura Yuichi Ishikawa Yasuyoshi Ouchi Hiroshi Horibe Nobuo Shirahashi Toru Kita
出版者
一般社団法人 日本動脈硬化学会
雑誌
Journal of Atherosclerosis and Thrombosis (ISSN:13403478)
巻号頁・発行日
vol.13, no.4, pp.202-208, 2006 (Released:2006-08-15)
参考文献数
15
被引用文献数
87 126

To determine the prevalence of metabolic syndrome in the Japanese general population, we analyzed data from a nationwide survey conducted in 2000. According to the Japanese new diagnostic criteria for metabolic syndrome in 2005, we analyzed 3,264 people aged from 20 to 79 (men, 1,917; women, 1,347) from the total participants. The incidence of metabolic syndrome was 7.8%. Men had a higher incidence (12.1%) than women (1.7%). Most of the women satisfying the criteria were 50 years old or over, while the incidence in men started to rise from their 30s. When we applied the criteria of Adult Treatment Panel III, the incidence was about 3-fold higher. In this population visceral obesity was associated with metabolic abnormalities, such as higher LDL-cholesterol, triglyceride, glucose, and blood pressure and lower HDL-cholesterol. Thus we determined the incidence of metabolic syndrome and each metabolic abnormality in the Japanese general population in 2000 and found an association of visceral obesity with metabolic abnormalities. Intervention to reduce the incidence of metabolic syndrome in Japan is necessary to reduce the risk of cardiovascular disease.
著者
Naoshi Hirata Shiro Ohmi Shin'ichi Sakai Kei Katsumata Satoshi Matsumoto Tetsuo Takanami Akira Yamamoto Takashi Iidaka Taku Urabe Mayumi Sekine Tooru Ooida Fumihito Yamazaki Hiroshi Katao Yasuhiro Umeda Masao Nakamura Norihiko Seto Takeshi Matsushima Hiroshi Shimizu Japanese University Group of the Urgent Joint
出版者
The Seismological Society of Japan, The Volcanological Society of Japan, The Geodetic Society of Japan
雑誌
Journal of Physics of the Earth (ISSN:00223743)
巻号頁・発行日
vol.44, no.4, pp.317-328, 1996 (Released:2009-04-30)
参考文献数
21
被引用文献数
41 43

A disastrous earthquake with a magnitude of 7.2 hit the southern part of Hyogo Prefecture on January 17, 1995. The mainshock was located on an active fault of the Arima-Takatsuki-Rokko fault system. Its focal mechanism was consistent with a right-lateral strike-slip fault trending N40°E. Three days after the occurrence of the mainshock, we started to install a highly dense seismic array in and around the fault area of the quake. Two permanent regional seismic networks of more than 30 stations covered the entire area of 200 km × 200 km. The temporarily installed array of 27 stations spanned the fault area of 15 km × 50 km. All data were telemetered to a temporary observation center at Uji. We located about 3, 100 aftershocks in real time for 1 month using an Internet connection between seismic networks. The aftershock area extended 70 km trending northeast to southwest. Hypocenters determined by the network were delivered automatically through the Internet. We found that the aftershock distribution was heterogeneous in space and time: seven clusters of hypocenters were identified and temporary variation in the rate of occurrence of aftershocks had a periodic component with periods of a half of day, 1 day, and 3 days, that are superimposed on decaying of the rate following Omori's law.
著者
Hidenori Arai Akira Yamamoto Yuji Matsuzawa Yasushi Saito Nobuhiro Yamada Shinichi Oikawa Hiroshi Mabuchi Tamio Teramoto Jun Sasaki Noriaki Nakaya Hiroshige Itakura Yuichi Ishikawa Yasuyoshi Ouchi Hiroshi Horibe Tohru Egashira Hiroaki Hattori Nobuo Shirahashi Toru Kita
出版者
一般社団法人 日本動脈硬化学会
雑誌
Journal of Atherosclerosis and Thrombosis (ISSN:13403478)
巻号頁・発行日
vol.12, no.5, pp.240-250, 2005 (Released:2005-10-05)
参考文献数
53
被引用文献数
27 31

We studied the association of six common polymorphisms of four genes related to lipid metabolism with serum lipid levels. We selected single-nucleotide polymorphisms (SNPs) in the genes for cholesteryl ester transfer protein (CETP), lipoprotein lipase (LPL), hepatic lipase (LIPC), and apolipoprotein CIII (APOC3), and studied 2267 individuals randomly selected from the participants of Serum Lipid Survey 2000. There was a significant association of CETP polymorphism (D442G, Int14 +1 G → A, and TaqIB), LPL polymorphism (S447X), and LIPC polymorphism (−514 → CT) with HDL-cholesterol levels. We also found a significant association of LPL polymorphism (S447X) and APOC3 polymorphism (SstI) with triglyceride levels. This is the largest database showing the association of common genetic variants in lipid metabolism with serum lipid levels in the general Japanese population. Further study is necessary to elucidate the role of these gene polymorphisms in cardiovascular events.
著者
Hirotaka Yamamoto Mami Iima Yo Kishimoto Ayami Ohno Kishimoto Sho Koyasu Akira Yamamoto Yoshitaka Kawai Akira Yoshizawa Koichi Omori
出版者
Japanese Society for Magnetic Resonance in Medicine
雑誌
Magnetic Resonance in Medical Sciences (ISSN:13473182)
巻号頁・発行日
pp.mp.2021-0149, (Released:2022-03-04)
参考文献数
26
被引用文献数
1

Purpose: To evaluate whether readout-segmented echo-planar imaging (RS-EPI) diffusion-weighted imaging (DWI) can reduce image distortion and improve the lesion identification in parathyroid adenomas (PTAs) compared to single-shot EPI (SS-EPI) DWI, and to determine whether PTAs can be differentiated from other soft tissue structures of the head and neck region by using the apparent diffusion coefficient (ADC) value.Methods: We retrospectively analyzed the preoperative MR images including DWI of 24 patients with surgically confirmed PTA. RS-EPI and SS-EPI DWI were evaluated by two independent readers for the identification of the lesions and distortion. The ADC values of the PTAs were compared with those of thyroid glands and cervical lymph nodes.Results: RS-EPI provided significantly less distortion compared to SS-EPI. RS-EPI tended to have better lesion identification compared with SS-EPI without a statistically significant difference. On SS-EPI, the PTAs had significantly higher ADC values compared with the cervical lymph nodes. On RS-EPI, the PTAs had significantly higher ADC values compared with the thyroid glands and cervical lymph nodes.Conclusion: RS-EPI reduces the DWI distortion in PTAs. The ADC value obtained using RS-EPI enables the differentiation of PTAs from nearby structures, such as thyroid glands and cervical lymph nodes.
著者
Toshiro WATANABE Akira YAMAMOTO Shiro NAGAI Shigeru TERABE
出版者
The Japan Society for Analytical Chemistry
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.13, no.4, pp.571-575, 1997-08-10 (Released:2006-07-07)
参考文献数
13
被引用文献数
17 20

Capillary electrophoretic methods have been developed for the analysis of Monascus yellow pigments for food additives. Monascus yellow pigments were successfully separated by micellar electrokinetic chromatography (MEKC) with a 20mM sodium dodecyl sulfate (SDS) solution containing 50mM phosphate buffer, pH 7.0, and 20% acetonitorile or a 2.0% butyl acrylate/butyl methacrylate/methacrylic acid copolymer sodium salts (BBMA) solution containing 20mM ammonium formate buffer, pH 7.0, and 10% methanol. The xanthomonasin A was identified with the molecular mass measured by FABMS. Monascus yellow pigments were extracted from candies with solid phase extraction and analyzed by the developed technique.
著者
Akira Yamamoto
出版者
一般社団法人 日本動脈硬化学会
雑誌
Journal of Atherosclerosis and Thrombosis (ISSN:13403478)
巻号頁・発行日
vol.15, no.6, pp.304-305, 2008 (Released:2008-12-23)
参考文献数
22
被引用文献数
8 23