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OBJECTIVES: We sought to assess myocardial perfusion and metabolism in patients with peculiar transient asynergy, which consisted of basal normokinesia and apical akinesia of the left ventricle (LV) at the same time. BACKGROUND: This asynergy has been widely called "tako-tsubo-like LV dysfunction" in Japan, but little is known about its pathophysiology. METHODS: We performed rest tallium-201 ((201)Tl) and iodine-123-beta-methyl-p-iodophenyl penta-decanoic acid ((123)I-BMIPP) dual-isotope myocardial single-photon emission computed tomography (SPECT) in 14 patients with tako-tsubo-like LV dysfunction. The LV was divided into 17 segments, and each segment was graded with scores between normal uptake (0) and defect (4). We also measured the Thrombolysis in Myocardial Infarction trial (TIMI) frame count in 28 patients and 20 control subjects. RESULTS: Early SPECT (5 +/- 3 days) revealed that the total defect score value with BMIPP was significantly higher than reduced uptake with (201)Tl (p < 0.01). Reduced uptake of BMIPP was observed in parallel with an apical akinetic region and usually involved uptake of (201)Tl. This discrepancy improved gradually during the follow-up period (29 +/- 6 days) (p = 0.36). Compared with control subjects, patients had a TIMI frame count that was significantly higher in all coronary arteries immediately after onset. This higher TIMI frame count decreased but was sustained even after resolution of tako-tsubo-like LV dysfunction. CONCLUSIONS: Our data suggest that myocardial fatty acid metabolism is more severely impaired than myocardial perfusion, in parallel with an apical akinetic region during the early phase, and that impaired multivessel coronary microcirculation is involved, at least in part, in tako-tsubo-like LV dysfunction.  相似文献   
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Quality of life (QOL) has been defined in many ways, and these definitions usually emphasize happiness and satisfaction with life. Health‐related problems are known to cause lower QOL. However, the neural mechanisms underlying individual differences in QOL measured by questionnaire (QOLMQ) in young healthy subjects are unknown. QOL is essential to our well‐being, and investigation of the neural mechanisms underlying QOL in uncompromised subjects is obviously of great scientific and social interest. We used voxel‐based morphometry to investigate the association between regional gray matter volume (rGMV) and QOLMQ across the brain in healthy young adults (age, 21.4 ± 1.8 years) men (n = 88) and women (n = 68) in humans. We found significant negative relationships between QOLMQ and rGMV in a region in the left rostrolateral prefrontal cortex and regions in the dorsal part of the anterior cingulate gyrus and contingent cingulate regions. These findings show that structural variations in regions associated with processing of negative emotions such as fear and anger as well as those associated with evaluation of internally generated information are associated with QOLMQ. These findings suggest that these processes might be related to QOLMQ in healthy young adults. Hum Brain Mapp 35:1834–1846, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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Although smectite-type clays are used as heterogeneous media for photofunctional guest molecules, the guest species are limited to cationic or polar molecules because of the intrinsic negative electric charges of clay particles. Nevertheless, in this study, aqueous clay colloids are reported to affect the photoisomerization kinetics of anionic and cationic azobenzene molecules dissolved in the colloids. Under UV-light irradiation, the clay colloids decelerate trans-to-cis isomerization, while under visible-light irradiation, the clay colloids accelerate cis-to-trans isomerization. In addition, the sol–gel transition of clay colloids affects the kinetics. The results considerably expand the applicability of clay colloids as matrixes for functional organic species.

Aqueous clay colloids influence the photoisomerization kinetics of both of the anionic and cationic azobenzene molecules although the guest species has been limited to cationic or polar molecules because of the intrinsic negative electric charges of the clay particles.  相似文献   
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