著者
Kenta Yoshida Rustam Orozbaev Takao Hirajima Akira Miyake Akira Tsuchiyama Apas Bakirov Akira Takasu Kadyrbek Sakiev
出版者
GEOCHEMICAL SOCIETY OF JAPAN
雑誌
GEOCHEMICAL JOURNAL (ISSN:00167002)
巻号頁・発行日
vol.52, no.1, pp.59-67, 2018 (Released:2018-02-02)
参考文献数
42
被引用文献数
5 5

Direct chemical analysis of a single fluid inclusion was conducted by micro-excavation at cryo-temperatures. A scanning electron microscope (SEM) equipped with a focused ion beam (FIB), an energy dispersive X-ray spectrometer (EDS), and a cold stage, were used to analyze the chemical composition of the sample fluid inclusion, which was trapped in the ultrahigh-pressure (UHP) talc-garnet-chloritoid schist obtained from the Makbal metamorphic complex, Kyrgyz. Conventional techniques such as microthermometry and cryo-temperature and room-temperature Raman spectroscopy enabled the detection of NaCl and CaCl2 as solute species in the fluid inclusions, as well as high salinity of 20.5 mass% CaCl2 and 1.7 mass% NaCl with the assumption of a NaCl-CaCl2-H2O ternary system. However, additional chemical analysis using the present cryo-FIB-SEM-EDS system further revealed the presence of K as a solute element, which is hardly identified by conventional techniques. Petrographic examination of the fluid inclusions indicated that they had been trapped during the exhumation stage of the UHP talc-garnet-chloritoid schist, possibly originating from the decompression breakdown of lawsonite. The data acquired from the present study challenges previous reports of the existence of simple chemical system of aqueous fluids in high-pressure and UHP metamorphic terrane in eastern Asia. This is imperative because misidentification of solute species introduces errors into salinity estimation, resulting in inaccuracy propagation in quantitative analytical processes such as LA-ICP-MS. A detailed fluid inclusion petrography would thus require accurate quantitative analysis involving FIB-based sample-preparation and SEM-EDS analysis.
著者
Kazuhiro Takahashi Wataru Shimizu Akira Miyake Taisuke Nabeshima Mami Nakayashiro Hitoshi Ganaha
出版者
The Japanese Circulation Society
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
vol.78, no.8, pp.1974-1979, 2014-07-25 (Released:2014-07-25)
参考文献数
33
被引用文献数
16 15

Background:Genetic testing for long QT syndrome (LQTS) is now in clinical practice. We conducted molecular genetic analyses to definitively diagnose LQTS and to determine its subtypes for gene-specific treatment. We conducted a retrospective study to determine the characteristics of schoolchildren with LQTS living on the Okinawa Islands.Methods and Results:The study population included children identified in a school-based electrocardiographic (ECG) screening program for cardiovascular diseases who were referred to Okinawa Children’s Medical Center between 2007 and 2012; 23 children met the diagnostic criteria for LQTS. Of them, 17 were genotype-positive and 14 were found to harbor theSCN5AE1784K mutation exclusively among the LQTS genotype-positive children. The children were divided into genotype-positive and -negative groups. Clinical characteristics and ECG data were analyzed and compared. The median Schwartz score was 3. The median QT interval was 521 ms.Conclusions:The major finding is that the prevalent subtype of LQTS in Okinawa is discordant with other cohorts living in other regions of Japan or overseas. We cannot exclude the possibility of the presence of a specific founder mutation in this geographically clustered population, particularly considering that the hospital is the only tertiary heart center for children in Okinawa. However, this uniquely high prevalence of theSCN5AE1784K mutation serves as a compelling justification to conduct a larger study. (Circ J 2014; 78: 1974–1979)