119 research outputs found

    Subspace Variational Quantum Simulator

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    Quantum simulation is one of the key applications of quantum computing, which can accelerate research and development in chemistry, material science, etc. Here, we propose an efficient method to simulate the time evolution driven by a static Hamiltonian, named subspace variational quantum simulator (SVQS). SVQS employs the subspace-search variational eigensolver (SSVQE) to find a low-energy subspace and further extends it to simulate dynamics within the low-energy subspace. More precisely, using a parameterized quantum circuit, the low-energy subspace of interest is encoded into a computational subspace spanned by a set of computational basis, where information processing can be easily done. After the information processing, the computational subspace is decoded to the original low-energy subspace. This allows us to simulate the dynamics of low-energy subspace with lower overhead compared to existing schemes. While the dimension is restricted for feasibility on near-term quantum devices, the idea is similar to quantum phase estimation and its applications such as quantum linear system solver and quantum metropolis sampling. Because of this simplicity, we can successfully demonstrate the proposed method on the actual quantum device using Regetti Quantum Cloud Service. Furthermore, we propose a variational initial state preparation for SVQS, where the initial states are searched from the simulatable eigensubspace. Finally, we demonstrate SVQS on Rigetti Quantum Cloud Service

    Evaluating the Quality of Life of People with Dementia in Residential Care Facilities

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    Aims: Our purpose was to compare recipient and caregiver perception of the quality of life (QoL) of people with dementia in residential care facilities and to identify the factors associated with their perception of QoL. Methods: Residents' QoL was evaluated by both the patient and the caregiver, using the Quality of Life in Alzheimer's Disease and several other indices. Results: The correlation between the self-rated QoL score and the staff-rated QoL score was low. Conclusions: The staff tended to underestimate QoL. The main determinants of QoL were the functional status and depression. Improving physical function and mood may be beneficial in providing a better QoL.ArticleDEMENTIA AND GERIATRIC COGNITIVE DISORDERS. 32(1):39-44 (2011)journal articl

    Functional Imaging of Hepatic Masses Using Computed Tomography

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    In order to assess the usefulness of CT functional images, twenty one cases with liver masses were studied. We tried to minimize the motion artifacts by immobilizing the patients with a girdle in performing dynamic CT scans, and by discarding some of the segmented images with serious artifacts before constructing functional images. The qualities of images obtained were considered satisfactory. Of the several transit parameters obtained from the dynamic CT scans, we found the first moment (Ml) to be most useful and the effectiveness of Ml-functional images were studied. In all cases with hepatocellular carcinomas (12 cases) and intrahepatic cholangiocarcinomas (2 cases), the Ml-functional images showed the viable portions of tumors as accumulations of dark pixels reflecting rapid transit times due to arterial blood supply. In three cases with hepatic cavernous hemangiomas, the lesions were represented as bright areas with a well-defined border. In two cases with hepatic abscesses, the Ml-functional images suggested the presence of hyperemia in the surrounding tissue as demonstrated by bright pixels around the lesions. CT functional imaging was proved to be useful for evaluating the circulatory dynamics of contrast material and the differential diagnosis of liver tumors when conventional or dynamic CT studies failed to provide enough information. This technique enabled overall analysis of time-density curves for the entire plane of an image semiautomatically and without the subjective maneuver of setting ROI's (regions of interest)

    Deep Adversarial Reinforcement Learning With Noise Compensation by Autoencoder

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    We present a new adversarial learning method for deep reinforcement learning (DRL). Based on this method, robust internal representation in a deep Q-network (DQN) was introduced by applying adversarial noise to disturb the DQN policy; however, it was compensated for by the autoencoder network. In particular, we proposed the use of a new type of adversarial noise: it encourages the policy to choose the worst action leading to the worst outcome at each state. When the proposed method, called deep Q-W-network regularized with an autoencoder (DQWAE), was applied to seven different games in an Atari 2600, the results were convincing. DQWAE exhibited greater robustness against the random/adversarial noise added to the input and accelerated the learning process more than the baseline DQN. When applied to a realistic automatic driving simulation, the proposed DRL method was found to be effective at rendering the acquired policy robust against random/adversarial noise

    Unique arrangement of bone matrix orthogonal to osteoblast alignment controlled by Tspan11-mediated focal adhesion assembly

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    During tissue construction, cells coordinate extracellular matrix (ECM)assembly depending on the cellular arrangement. The traditional understanding of the relationship between the ECM and cells is limited to the orientation-matched interaction between them. Indeed, it is commonly accepted that the bone matrix (collagen/apatite)is formed along osteoblast orientation. Nonetheless, our recent findings are contrary to the above theory; osteoblasts on nanogrooves organize formation of the bone matrix perpendicular to cell orientation. However, the precise molecular mechanisms underlying the orthogonal organization of bone matrix are still unknown. Here, we show that mature fibrillar focal adhesions (FAs)facilitate the perpendicular arrangement between cells and bone matrix. The osteoblasts aligned along nanogrooves expressed highly mature fibrillar FAs mediated by integrin clustering. Microarray analysis revealed that Tspan11, a member of the transmembrane tetraspanin protein family, was upregulated in cells on the nanogrooved surface compared with that in cells on isotropic, flat, or rough surfaces. Tspan11 silencing significantly disrupted osteoblast alignment and further construction of aligned bone matrix orthogonal to cell orientation. Our results demonstrate that the unique bone matrix formation orthogonal to cell alignment is facilitated by FA maturation. To the best of our knowledge, this report is the first to show that FA assembly mediated by Tspan11 determines the direction of bone matrix organization.Nakanishi Y., Matsugaki A., Kawahara K., et al. Unique arrangement of bone matrix orthogonal to osteoblast alignment controlled by Tspan11-mediated focal adhesion assembly. Biomaterials, 209, 103. https://doi.org/10.1016/j.biomaterials.2019.04.016

    近赤外線スベクトロスコピィを用いた小児期自閉スペクトラム症の前頭前野における血液動態反応の低下

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    Background: Functional neuroimaging studies suggest that prefrontal cortex dysfunction is present in people with autism spectrum disorder (ASD). Near-infrared spectroscopy is a noninvasive optical tool for examining oxygenation and hemodynamic changes in the cerebral cortex by measuring changes in oxygenated hemoglobin. Methods: Twelve drug-naïve male participants, aged 7-15 years and diagnosed with ASD according to DSM-5 criteria, and 12 age- and intelligence quotient (IQ)-matched healthy control males participated in the present study after giving informed consent. Relative concentrations of oxyhemoglobin were measured with frontal probes every 0.1 s during the Stroop color-word task, using 24-channel near-infrared spectroscopy. Results: Oxyhemoglobin changes during the Stroop color-word task in the ASD group were significantly smaller than those in the control group at channels 12 and 13, located over the dorsolateral prefrontal cortex (FDR-corrected P: 0.0021-0.0063). Conclusion: The results suggest that male children with ASD have reduced prefrontal hemodynamic responses, measured with near-infrared spectroscopy.博士(医学)・乙第1442号・令和元年12月5日© The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/ publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated

    An exploratory study for tuft cells in the breast and their relevance in triple-negative breast cancer: the possible relationship of SOX9

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    BACKGROUND: Breast cancer is highly heterogeneous, suggesting that small but relevant subsets have been under-recognized. Rare and mainly triple-negative breast cancers (TNBCs) were recently found to exhibit tuft cell-like expression profiles, including POU2F3, the tuft cell master regulator. In addition, immunohistochemistry (IHC) has identified POU2F3-positive cells in the normal human breast, suggesting the presence of tuft cells in this organ. METHODS: Here, we (i) reviewed previously identified POU2F3-positive invasive breast cancers (n = 4) for POU2F3 expression in intraductal cancer components, (ii) investigated a new cohort of invasive breast cancers (n = 1853) by POU2F3-IHC, (iii) explored POU2F3-expressing cells in non-neoplastic breast tissues obtained from women with or without BRCA1 mutations (n = 15), and (iv) reanalyzed publicly available single-cell RNA sequencing (scRNA-seq) data from normal breast cells. RESULTS: Two TNBCs of the four previously reported invasive POU2F3-positive breast cancers contained POU2F3-positive ductal carcinoma in situ (DCIS). In the new cohort of invasive breast cancers, IHC revealed four POU2F3-positive cases, two of which were triple-negative, one luminal-type, and one triple-positive. In addition, another new POU2F3-positive tumor with a triple-negative phenotype was found in daily practice. All non-neoplastic breast tissues contained POU2F3-positive cells, irrespective of BRCA1 status. The scRNA-seq reanalysis confirmed POU2F3-expressing epithelial cells (3.3% of all epithelial cells) and the 17% that co-expressed the other two tuft cell-related markers (SOX9/AVIL or SOX9/GFI1B), which suggested they were bona fide tuft cells. Of note, SOX9 is also known as the "master regulator" of TNBCs. CONCLUSIONS: POU2F3 expression defines small subsets in various breast cancer subtypes, which can be accompanied by DCIS. The mechanistic relationship between POU2F3 and SOX9 in the breast warrants further analysis to enhance our understanding of normal breast physiology and to clarify the significance of the tuft cell-like phenotype for TNBCs

    Long-term outcomes of microendoscopic laminoplasty in patients with lumbar spinal stenosis: impact of the surgical approach and facet tropism

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     Microendoscopic laminoplasty (MEL) is the surgical procedure of choice at our institution for decompressing nerve roots in lumbar spinal stenosis (LSS). This minimally invasive procedure allows for bilateral decompression via unilateral endoscopic surgical access and maximum preservation of the lumbar zygapophyseal (facet) joints at the level (s) of interest. For this procedure, the surgical approach is generally made on the ipsilateral side of the stenosis. However, this rule of thumb is not always applicable because of lumbar facet joint degeneration and variations in the long-axis orientation of the spinous processes.  Few studies to date have proposed criteria about the surgical approach for MEL. Surgeons use their clinical judgment to decide on a case-by-case basis. Facet tropism is frequently encountered in patients with LSS undergoing MEL. Long-term postoperative changes in spinal alignment parameters could guide selection of the side for the surgical approach in MEL. This retrospective study included 45 patients who underwent MEL for single-level LSS between April 1, 2010 and June 30, 2014. The mean age of the patients was 74.8 ± 8.2 years; 23 (51%) were male. FT was defined as a bilateral facet joint angle difference of ≥10 degrees. Study variables included lumbar lordosis angle, Cobb angle, and vertebral slippage based on standing radiographic images. The study population was divided into two groups based on the degree of facet joint sagittal orientation on the side of the incision. Specifically, patients in whom the surgical approach was made on the side of the more sagittally oriented facet joint were categorized into Group S. The other patients were categorized into Group N. The percent change in mean Cobb angle between preoperative and postoperative assessments was 124 ± 164% for Group S and 45.6 ± 62.5% for Group N (P < 0.05), indicating postoperative progression of scoliosis in Group S. Considering the postoperative risk of scoliosis and related complications, approaching from the side of the less sagittally oriented facet joint is preferable in MEL for the treatment of LSS in patients with FT

    リポポリサッカライドの外因性投与はコリン欠乏 L-アミノ酸置換食誘発脂肪性肝炎モデルマウスにおいて肝線維化を促進する

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    Various rodent models have been proposed for basic research; however, the pathogenesis of human nonalcoholic steatohepatitis (NASH) is difficult to closely mimic. Lipopolysaccharide (LPS) has been reported to play a pivotal role in fibrosis development during NASH progression via activation of toll-like receptor 4 (TLR4) signaling. This study aimed to clarify the impact of low-dose LPS challenge on NASH pathological progression and to establish a novel murine NASH model. C57BL/6J mice were fed a choline-deficient l-amino-acid-defined (CDAA) diet to induce NASH, and low-dose LPS (0.5 mg/kg) was intraperitoneally injected thrice a week. CDAA-fed mice showed hepatic CD14 overexpression, and low-dose LPS challenge enhanced TLR4/NF-κB signaling activation in the liver of CDAA-fed mice. LPS challenge potentiated CDAA-diet-mediated insulin resistance, hepatic steatosis with upregulated lipogenic genes, and F4/80-positive macrophage infiltration with increased proinflammatory cytokines. It is noteworthy that LPS administration extensively boosted pericellular fibrosis with the activation of hepatic stellate cells in CDAA-fed mice. Exogenous LPS administration exacerbated pericellular fibrosis in CDAA-mediated steatohepatitis in mice. These findings suggest a key role for LPS/TLR4 signaling in NASH progression, and the authors therefore propose this as a suitable model to mimic human NASH.博士(医学)・甲第738号・令和2年3月16日© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)
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