著者

Miho Nishitani-Yokoyama Katsumi Miyauchi Kazunori Shimada Takayuki Yokoyama Shohei Ouchi Tatsuro Aikawa Mitsuhiro Kunimoto Miki Yamada Akio Honzawa Shinya Okazaki Hiroyuki Daida

出版者

The Japanese Circulation Society

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

vol.83, no.1, pp.101-109, 2018-12-25 (Released:2018-12-25)

参考文献数

23

被引用文献数

1 13

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Background:Cardiac rehabilitation (CR) is an established multidisciplinary secondary preventive program. We investigated the effects of CR involving intensive physical activity (PA) on coronary plaque volume and components in patients with acute coronary syndrome (ACS).Methods and Results:We enrolled 32 consecutive patients with ACS in early phase II CR and randomly assigned them to an intensive CR group (n=18; CR participation ≥twice/week, daily PA ≥9,000 steps) or a standard CR group (n=14; CR participation ≥once/2weeks, daily PA ≥6,000 steps). Serial integrated backscatter intravascular ultrasound was performed for non-culprit lesions at baseline and after 8 months. Baseline clinical data were identical between the 2 groups. Unexpectedly, CR participation and PA did not differ significantly between the 2 groups, and there was no significant difference in plaque volume (PV) or components between the 2 groups. Subsequently, we classified the patients into 2 groups according to median PA (7,000 steps). There were significant differences in percent change of PV and of lipid volume between these 2 groups. In addition, these changes were negatively and independently correlated with PA.Conclusions:No significant difference was observed in PV or components between the intensive CR and the standard CR groups. Intensive PA, however, may retard coronary PV and ameliorate lipid component in patients with ACS participating in late phase II CR.

著者

Tatsuro Aikawa Tetsuro Miyazaki Kazunori Shimada Yurina Sugita Megumi Shimizu Shohei Ouchi Tomoyasu Kadoguchi Yasutaka Yokoyama Tomoyuki Shiozawa Masaru Hiki Shuhei Takahashi Hamad Al Shahi Shizuyuki Dohi Atsushi Amano Hiroyuki Daida

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

pp.38315, (Released:2017-03-22)

参考文献数

31

被引用文献数

17

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Aim: Omega-3 polyunsaturated fatty acids (PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been reported to reduce the risk of cardiovascular disease. However, whether omega-3 PUFAs are involved in the pathogenesis of abdominal aortic aneurysms (AAA) remains unclear.Methods: We analyzed 67 consecutive patients admitted for the elective surgical repair of AAA. We investigated the association of serum EPA and DHA levels as well as the EPA/AA ratio with the size of AAA assessed using three-dimensional reconstructed computed tomography images.Results: Mean patient age was 70±9 years and 60 patients were male. Serum EPA and DHA levels were 75.2±35.7 μg/mL and 146.1±48.5 μg/mL, respectively. EPA/AA ratio was 0.44±0.22, which was lower than those in healthy Japanese subject and equivalent to those in Japanese patients with coronary artery disease as previously reported. Mean of the maximum AAA diameter was 56.4±8.9 mm, and serum EPA levels and EPA/AA ratio negatively correlated with it (r=−0.32 and r=−0.32, respectively). Multiple liner regression analysis showed that EPA levels were significant independent factor contributing to the maximum AAA diameter. Furthermore, low serum EPA levels and low EPA/AA ratio were significantly associated with the growth rate of AAA diameter (r=−0.43 and r=−0.33, respectively).Conclusion: EPA levels in patients with AAA were relatively low. Low serum EPA levels and EPA/AA ratio were associated with the size and growth rate of AAA.

著者

Taro Sugai Kohei Takano Shohei Ouchi Satoshi Ito

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.2020-0073, (Released:2021-02-11)

参考文献数

24

被引用文献数

2

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Purpose: To improve the performance of a denoising convolutional neural network (DnCNN) and to make it applicable to images with inhomogeneous noise, a refinement involving an activation function (AF) and an application of the refined method for inhomogeneous-noise images was examined in combination with parallelized image denoising.Methods: Improvements in the DnCNN were performed by three approaches. One is refinement of the AF of each neural network that constructs the DnCNN. Swish was used in the DnCNN instead of rectifier linear unit. Second, blind noise removal was introduced to the DnCNN in order to adapt spatially variant noises. Third, blind noise removal was applied to parallelized image denoising, referred to herein as ParBID. The ParBID procedure is as follows: (1) adjacent 2D slice images are linearly combined to obtained higher peak SNR (PSNR) images, (2) combined images with different weight coefficients are denoised using the blind DnCNN, and (3) denoised combined images are separated into original position images by algebraic calculation.Results: Experimental studies showed that the PSNR and the structural similarity index (SSIM) were improved by using Swish for all noise levels, from 2.5% to 7.5%, as compared to the conventional DnCNN. It was also shown that a well-trained CNN could remove spatially variant noises superimposed on images. Experimental studies with ParBID showed that the greatest PSNR and SSIM improvements were obtained at the middle slice when three slice images were used for linear image combination. More fine structures of images and image contrast remained when the proposed ParBID procedure was used.Conclusion: Swish can improve the denoising performance of the DnCNN, and the denoising performance and effectiveness were further improved by ParBID.

著者

Shohei Ouchi Satoshi Ito

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.2019-0139, (Released:2020-07-02)

参考文献数

28

被引用文献数

8

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Purpose: A deep residual learning convolutional neural network (DRL-CNN) was applied to improve image quality and speed up the reconstruction of compressed sensing magnetic resonance imaging. The reconstruction performances of the proposed method was compared with iterative reconstruction methods.Methods: The proposed method adopted a DRL-CNN to learn the residual component between the input and output images (i.e., aliasing artifacts) for image reconstruction. The CNN-based reconstruction was compared with iterative reconstruction methods. To clarify the reconstruction performance of the proposed method, reconstruction experiments using 1D-, 2D-random under-sampling and sampling patterns that mix random and non-random under-sampling were executed. The peak-signal-to-noise ratio (PSNR) and the structural similarity index (SSIM) were examined for various numbers of training images, sampling rates, and numbers of training epochs.Results: The experimental results demonstrated that reconstruction time is drastically reduced to 0.022 s per image compared with that for conventional iterative reconstruction. The PSNR and SSIM were improved as the coherence of the sampling pattern increases. These results indicate that a deep CNN can learn coherent artifacts and is effective especially for cases where the randomness of k-space sampling is rather low. Simulation studies showed that variable density non-random under-sampling was a promising sampling pattern in 1D-random under-sampling of 2D image acquisition.Conclusion: A DRL-CNN can recognize and predict aliasing artifacts with low incoherence. It was demonstrated that reconstruction time is significantly reduced and the improvement in the PSNR and SSIM is higher in 1D-random under-sampling than in 2D. The requirement of incoherence for aliasing artifacts is different from that for iterative reconstruction.

著者

Masaru Hiki Tetsuro Miyazaki Kazunori Shimada Yurina Sugita Megumi Shimizu Tatsuro Aikawa Shohei Ouchi Tomoyuki Shiozawa Kiyoshi Takasu Shuhei Takahashi Atsutoshi Takagi Katsumi Miyauchi Hiroyuki Daida

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

pp.37424, (Released:2017-03-24)

参考文献数

27

被引用文献数

9

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Aim: Polyunsaturated fatty acids (PUFAs) take part in various biological events linked to the pathogenesis of venous thromboembolism (VTE), including inflammation, endothelial dysfunction, and hypercoagulability. Several studies have demonstrated the association between PUFAs and the occurrence of VTE. However, the role of PUFAs in the pathogenesis of VTE remains unclear.Methods: We enrolled 45 patients with acute VTE and 37 age-, gender-, and body mass index-matched healthy volunteers to examine their PUFA levels. Serum omega 3 (eicosapentaenoic acid: EPA and docosahexaenoic acid: DHA) and omega 6 (dihomogammalinolenic acid: DGLA and arachidonic acid: AA) fatty acids levels were measured within 24 h of admission.Results: Patients with VTE showed significantly higher AA and lower EPA levels, and lower EPA/AA ratios than the controls. Multivariate analysis revealed that AA was an independent marker for VTE. In addition, we divided the patients based on their median age (58 years old). The younger patients with VTE showed significantly lower EPA/AA levels than their age-matched controls, whereas older patients with VTE showed a significantly higher AA/DGLA levels than the older controls.Conclusions: High serum AA levels and low EPA levels are associated with the development of acute VTE, suggesting that the imbalance of PUFAs may be a potential therapeutic target for preventing acute VTE.