53 research outputs found
Machine learning technique using the signature method for automated quality control of the Argo profiles
A profile from the Argo ocean observation array is a sequence of
three-dimensional vectors composed of pressure, salinity, and temperature,
appearing as a continuous curve in three-dimensional space. The shape of this
curve is faithfully represented by a path signature, which is a collection of
all the iterated integrals. Moreover, the product of two terms of the signature
of a path can be expressed as the sum of higher-order terms. Thanks to this
algebraic property, a nonlinear function of profile shape can always be
represented by a weighted linear combination of the iterated integrals, which
enables machine learning of a complicated function of the profile shape. In
this study, we performed supervised learning for existing Argo data with
quality control flags by using the signature method, and demonstrated the
estimation performance by cross-validation. Unlike rule-based approaches, which
require several complicated and possibly subjective rules, this method is
simple and objective in nature because it relies only on past knowledge
regarding the shape of profiles. This technique should be critical to realizing
automatic quality control for Argo profile data.Comment: 21 pages. 13 figures, 1 table, in revisio
DNA複製におけるイニシエーター蛋白の役割
金沢大学遺伝子実験施設1.in vitro DNA複製系の検討GroEで再生したRep蛋白は、イニシエーターとして働く際に重要なiteronへの結合活性は非常に高い。しかしFullerらのFraction IIにこれを加えても、pSC101のin vitro DNA複製は起こらなかった。単にGroEで再生したRep monomerではiteronへの結合活性は高くてもイニシエーター活性が無いか、あるいはFullerらのFraction IIにはpSC101の複製に必要なfactorが足りないものと思われる。Rep蛋白のdiner形成に関わる領域の同定及び変異型Rep蛋白の単離Rep蛋白のN末端には、ロイシンが7アミノ酸ごとに4回繰り返したロイシンジッパー構造を取り得る領域がある。このモチーフ内の2番目あるいは3番目のロイシンをグリシンまたはプロリンに変えた4種類の変異型Rep蛋白を作製し、その性質を調べた。その結果いずれの変異型Rep蛋白もin vivoにおいて、イニシエーター活性、リプレッサー活性ともに低下していた。マルトース結合蛋白との融合蛋白の形で精製し,in vitroにおけるDNA結合活性を調べたところ、monomer型が結合するdirect repeat,dimer型が結合するinverted repratいずれに対しても結合能が低下した。塩酸グアニジン変性後再生しmonomer化した融合蛋白でもdirect repeatへの結合が弱かったことから、1アミノ酸の置換でDNA結合活性そのものが低下したものと思われる。4種類の変異型Rep蛋白がnative formでmonomerなのかdimerなのかまだ同定できていないが、モチーフ内の2番目、3番目のロイシンはDNA結合活性そのものに重要であることが分かった。研究課題/領域番号:07780600, 研究期間(年度):1995出典:研究課題「DNA複製におけるイニシエーター蛋白の役割」課題番号07780600(KAKEN:科学研究費助成事業データベース(国立情報学研究所)) (https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-07780600/)を加工して作
DNA複製におけるイニシエーター蛋白の役割
金沢大学助手研究課題/領域番号:61780231, 研究期間(年度):1986出典:研究課題「DNA複製におけるイニシエーター蛋白の役割」課題番号61780231(KAKEN:科学研究費助成事業データベース(国立情報学研究所)) (https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-61780231/)を加工して作
太陽光中のUVA/UVBの比率の季節差がDNA損傷(6-4)型光産物のDewar型光産物への光異性化の効率に影響を及ぼす
The UVA and UVB components of sunlight can produce three classes of bipyrimidine DNA photolesions [cyclobutane pyrimidine dimers (CPDs), pyrimidine (6-4) pyrimidone photoproducts (6-4PPs) and related Dewar valence isomers (DewarPPs)]. The UVA/UVB ratio of sunlight is high in winter and low in summer in the Northern Hemisphere. Since UVB radiation produces 6-4PPs and UVA radiation converts them into DewarPPs through photoisomerization, it is expected that there may be differences in the photoisomerization of 6-4PPs between summer and winter, although that has never been documented. To determine that, isolated DNA was exposed to natural sunlight for 8 h in late summer and in winter, and absolute levels of the three classes of photolesions were quantified using calibrated ELISAs. It was found that sunlight produces CPDs and 6-4PPs in DNA at a ratio of about 9:1 and converts approximately 80% of 6-4PPs into DewarPPs within 3 h. Moreover, photoisomerization is more efficient in winter than in late summer after sunlight irradiation for the same duration, at similar solar UV doses and with the same induction level of CPDs. These results demonstrate that seasonal differences in the UVA/UVB ratio influence the efficiency of the photoisomerization of 6-4PPs into DewarPPs.博士(医学)・甲第775号・令和3年3月15日© 2020 The Authors. Photochemistry and Photobiology published by Wiley Periodicals LLC on behalf of American Society for Photobiology.
This is an open access article under the terms of the Creative Commons Attribution License(https://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited
非ラフト部分のATP結合カセット輸送体A1の発現増強は、血管内皮細胞の志賀毒素に対する感受性を減少させる
Shiga toxin (Stx) binds to globotriaosyl ceramide (Gb3) receptors on the surface of vascular endothelial cells, which is followed by Gb3-dependent endocytosis, and initiates a cascade leading to cell damage. The Gb3 receptor is localized in lipid rafts, in which cholesterol is tightly packed primarily with sphingolipids in a liquid-ordered state. Recent studies have indicated that phosphodiesterase (PDE) type 4 inhibitors enhance the expression of ATP-binding cassette 1 (ABCA1) which promotes cholesterol efflux from non-rafts at the plasma membrane. Here we report that rolipram, a PDE4 inhibitor, reduced the sensitivity to Stx2 of human umbilical vascular endothelial cells in association with increased apolipoproteinA-I (apoA-I)-mediated cholesterol efflux, and shift of some Gb3 molecules from lipid rafts into non-rafts. Although rolipram treatment did not reduce Gb3 content at the plasma membrane and Stx binding to whole cells of HUVECs, it reduced Stx2 endocytosis. Knockdown of ABCA1 by transfection with siRNA ABCA1 in vascular endothelial cells abrogated the protective effect of rolipram on Stx2-exposed cells. Our present results suggest that the expression level of ABCA1 protein is one of critical determinants of Stx sensitivity levels in vascular endothelial cells.博士(医学)・乙1324号・平成26年3月17
Effect Of Isometric Exercises Using an Active Therapeutic Movement Device for Patients with Acute Low Back Pain
Background: This study aimed to investigate the effects of isometric exercise using ATM®2 for acute low back pain (LBP) patients as a flexion or extension type.
Methods: The subjects were twenty individuals (age 39.7±8.0ys, 12 males / 8 females) with acute LBP of less than four weeks duration who volunteered to participate in the study. The participants were allocated into four groups. First, the participants were classified by the direction of the movement causing pain in flexion and extension types. Secondly, both types were allocated randomly into two groups which were given exercises using the ATM®2 group and the usual care group. Finally, both groups were treated three times weekly for two weeks, totaling six sessions.
Results: In terms of the extension type of LBP, the effect of the extension pain in the ATM®2-group significantly decreased pain (p=0.04) immediately. And in both groups significantly decreased (p=0.01, 0.001) for two weeks of intervention. Furthermore, in the flexion type of LBP, the effect of the flexion pain in the ATM®2-group and usual care group significantly decreased (p=0.001, p=0.03) during the two weeks intervention. However, neither group had an immediate effect.
Conclusion: Isometric exercise using ATM®2 may have an immediate and short-term effect on acute LBP, which is greater in patients with an extension-type pattern. The ATM®2 exercise may reduce the pain of the acute LBP. Furthermore, it will be a problem in the future to analyze if the influence of pain is reduced in the immediate natural period that gives to chronic LBP
Myofibroblasts proliferation of idiopathic and collagen vascular disorders associated nonspecific interstitial pneumonia.
Nonspecific interstitial pneumonia (NSIP) has been recognized as a separate histological classification of interstitial lung disease. Similar features are found not only in idiopathic NSIP, but also in NSIP associated with collagen vascular disorder (CVD-NSIP). We examined the clinical symptoms, laboratory findings, and prognosis of 13 cases of idiopathic NSIP and 11 cases of CVD-NSIP. Immunohistochemical staining was performed using the streptavidin/biotin/peroxidase method with anti-alpha-smooth muscle actin antibody. No differences in the distribution of clinical features, laboratory findings, and prognosis were observed between idiopathic NSIP and CVD-NSIP. In immunohistochemical staining of the fibrosing areas, myofibroblasts were observed in 7 of 13 idiopathic NSIP cases, but in 10 of 11 CVD-NSIP cases. With regards to intra-alveolar organization, myofibroblasts were observed in all 10 CVD-NSIP cases, but they were observed in only 2 of 9 idiopathic NSIP cases. We found a significantly higher myofibroblast proliferation in the intra-alveolar organization of CVD-NSIP compared to idiopathic NSIP. Clinically, idiopathic NSIP and CVD-NSIP are similar, but are pathologically different.</p
High levels of oxidatively generated DNA damage 8,5'-cyclo-2'-deoxyadenosine accumulate in the brain tissues of xeroderma pigmentosum group A gene-knockout mice.
Xeroderma pigmentosum (XP) is a genetic disorder associated with defects in nucleotide excision repair, a pathway that eliminates a wide variety of helix-distorting DNA lesions, including ultraviolet-induced pyrimidine dimers. In addition to skin diseases in sun-exposed areas, approximately 25% of XP patients develop progressive neurological disease, which has been hypothesized to be associated with the accumulation of an oxidatively generated type of DNA damage called purine 8,5'-cyclo-2'-deoxynucleoside (cyclopurine). However, that hypothesis has not been verified. In this study, we tested that hypothesis by using the XP group A gene-knockout (Xpa-/-) mouse model. To quantify cyclopurine lesions in this model, we previously established an enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody (CdA-1) that specifically recognizes 8,5'-cyclo-2'-deoxyadenosine (cyclo-dA). By optimizing conditions, we increased the ELISA sensitivity to a detection limit of ˜one cyclo-dA lesion/106 nucleosides. The improved ELISA revealed that cyclo-dA lesions accumulate with age in the brain tissues of Xpa-/- and of wild-type (wt) mice, but there were significantly more cyclo-dA lesions in Xpa-/- mice than in wt mice at 6, 24 and 29 months of age. These findings are consistent with the long-standing hypothesis that the age-dependent accumulation of endogenous cyclopurine lesions in the brain may be critical for XP neurological abnormalities
A study on intraalveolar exudates in acute mycoplasma pneumoniae infection.
Pathologic features of Mycoplasma pneumoniae infection (M. pneumonia) are generally non-specific, and the literature regarding the pathologic features of M. pneumonia with intraalveolar exudates is limited. Clinical and histopathological studies were performed in 3 patients with M. pneumonia which did not respond to erythromycin and minocycline, but all rapidly recovered after corticosteroid therapy. In pathologic findings, we observed intraalveolar exudates and focal organization in M. pneumonia, and its intraalveolar lesions were compared between M. pneumonia and bronchiolitis obliterans organizing pneumonia containing fibrin (BOOP). Immunohistochemical studies were performed using the streptavidin biotin peroxidase complex method with anti-alpha-smooth muscle actin antibody and anti-pancytokeratin AE1/AE3 antibody. In pathologic findings, more fibrin deposits in intaalveolar lesions were observed in M. pneumonia than in BOOP. In intaalveolar lesions of M. pneumonia, a larger amount of nuclear debris, more neutrophils, and more erythrocytes were noted. Myofibroblasts were observed in the organization of BOOP, while in the intaalveolar lesions of M. pneumonia, myofibroblasts were not observed. These results suggest that M. pneumonia with intraalveolar exudates responds well to corticosteroid and its intraalveolar lesions apparently differed from those in BOOP.</p
Robot-directed speech detection using multimodal semantic confidence based on speech, image, and motion
ABSTRACT In this paper, we propose a novel method to detect robotdirected (RD) speech that adopts the Multimodal Semantic Confidence (MSC) measure. The MSC measure is used to decide whether the speech can be interpreted as a feasible action under the current physical situation in an object manipulation task. This measure is calculated by integrating speech, image, and motion confidence measures with weightings that are optimized by logistic regression. Experimental results show that, compared with a baseline method that uses speech confidence only, MSC achieved an absolute increase of 5% for clean speech and 12% for noisy speech in terms of average maximum F-measure
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