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Isolated loss of PMS2 immunohistochemical expression is frequently caused by heterogeneous MLH1 promoter hypermethylation in Lynch syndrome screening for endometrial cancer patients
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Inhibition of MEK1 Signaling Pathway in the Liver Ameliorates Insulin Resistance
Get PDF秋田大学博士(医学)Although mitogen-activated protein kinase kinase (MEK) is a key signaling molecule and a negative regulator of insulin action, it is still uncertain whether MEK can be a therapeutic target for amelioration of insulin resistance (IR) in type 2 diabetes (T2D) in vivo. To clarify whether MEK inhibition improves T2D, we examined the effect of continuous MEK inhibition with two structurally different MEK inhibitors, RO5126766 and RO4987655, in mouse models of T2D. RO5126766 and RO4987655 were administered via dietary admixture. Both compounds decreased blood glucose and improved glucose tolerance in doses sufficient to sustain inhibition of extracellular signal-regulated kinase (ERK)1/2 phosphorylation downstream of MEK in insulin-responsive tissues in db/db mice. A hyperinsulinemic-euglycemic clamp test showed increased glucose infusion rate (GIR) in db/db mice treated with these compounds, and about 60% of the increase was attributed to the inhibition of endogenous glucose production, suggesting that the liver is responsible for the improvement of IR. By means of adenovirus-mediated Mek1 shRNA expression, we confirmed that blood glucose levels are reduced by suppression of MEK1 expression in the liver of db/db mice. Taken together, these results suggested that the MEK signaling pathway could be a novel therapeutic target for novel antidiabetic agents
Acoustic radiation force impulse elastography for the differential diagnosis of liver tumors in patients with liver dysfunction
Get PDF秋田大学博士(医学)Objective : Acoustic radiation force impulse (ARFI) technology can measure the elasticity of tissue and tumor. The aim of this study was to evaluate whether the ARFI technology can differentiate cavernous hemangioma, hepatocellular carcinoma (HCC) and metastatic liver tumors in patients with liver dysfunction. Materials and Methods : Forty patients with liver dysfunction and liver tumors were enrolled in the study. The shear wave velocities (SWVs) in the tumors and background liver were examined by ARFI elastography under ultrasonography (US). Results : The SWVs in livers bearing HCCs were significantly higher than those of livers bearing cavernous hemangiomas. The SWVs in HCCs and metastatic liver tumors were significantly higher than those in cavernous hemangiomas. The SWVs in metastatic liver tumors were significantly higher than those in HCCs. The SWV ratio of metastatic liver tumor/parenchyma was significantly higher than that of cavernous hemangioma/parenchyma and HCC/parenchyma. There was a significant correlation between the tumor sizes and the SWVs in metastatic liver tumors. Conclusions : We herein demonstrated that ARFI elastography could noninvasively provide helpful information, without the need for biopsy, that could be used for the differential diagnosis among cavernous hemangiomas, HCCs and metastatic liver tumors in patients with liver dysfunction
The clinical course of a gastrointestinal stromal tumor (GIST) diagnosed by endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)
Get PDF秋田大学博士(医学)Objectives:
Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumor of the gastrointestinal tract. However, little is known about the clinical presentation of GIST, especially small lesions. The purpose of the present study was to clarify the efficacy of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for the diagnosis of GIST and to determine its clinical course.
Methods:
Pathological and clinical records of GIST extracted from our institutional database between 1996 and 2012 were reviewed. All GIST cases were diagnosed pathologically by surgical specimen or EUS-FNA. To examine the efficacy of EUS-FNA for the diagnosis of GIST, the pathological findings of EUS-FNA were compared with the surgical findings from resected cases. Next, to clarify the clinical presentation of GIST, imaging findings and changes in tumor size over time were evaluated in follow up.
Results:
Of 84 cases of GIST, 67 were resected surgically after EUS-FNA; tumor size was <20 mm in 19 patients, and ≥20 mm in 48 patients. For the diagnosis of small GIST<20 mm, sensitivity and positive predictive value of EUS-FNA were 81.3% and 100%, respectively. A total of 27 patients with GIST was follow up for more than 1 year. Tumor size increased significantly during follow up. However, generalized linear analysis showed that there was no significant relationship between tumor size and follow up period.
Conclusions:
The present results showed that even small GIST can be correctly identified by EUS-FNA. Moreover, size of small GIST increased significantly during follow up
Expression of cell competition markers at the interface between p53 signature and normal epithelium in the human fallopian tube
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Neutrophil elastase in amniotic fluid as a predictor of preterm birth after emergent cervical cerclage
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MicroRNA-150 inhibits tumor invasion and metastasis by targeting the chemokine receptor CCR6 ,in advanced cutaneous T-cell lymphoma
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Functional status of the articularis genus muscle in individuals with knee osteoarthritis.
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感性情報を考慮した人物画像処理の開発に関する検討
Get PDF秋田大学博士（工学）近年，ディジタルカメラやカメラ付き携帯電話などのカメラ機能を持つ電子端末の普及に伴い，私たちは手軽にディジタル写真や動画を撮影することが可能となり，個人の所有する写真・動画は増加傾向にある．特に，重要な被写体である「人物」の撮像された写真（人物写真）や動画は，ソーシャルネットワーキングサービス，動画共有サイト，並びにビデオチャットなどを介して多くの人に利用・共有されている．上記のような情報通信技術の発展によって人物写真や動画などのコンテンツが日常的に利用可能となった結果，①膨大な量の写真や動画を対象とし，ユーザの要求に適したコンテンツを抽出する「コンテンツ検索」や， ②ユーザの要求を満足するようにコンテンツ自体の品質を向上させる「コンテンツ高品質化」のように，ユーザの要求に合わせてコンテンツ利活用を可能にする機能（コンテンツ利活用機能）の開発が求められるようになった．このため，コンテンツ利活用機能の実現を目的とし，①膨大な写真の中から品質の高い写真を検索するために，画像処理を用いて写真に含まれる感性情報を評価する方法や， ②写真・動画の高品質化を目的として，そのコンテンツ自体に画像処理を施し高品質化を図る方法など，感性情報を考慮した人物画像処理の開発が行われている．しかしながら，ユーザの感性的な評価は定性的な評価を含むことが多く，感性情報を考慮した人物画像処理の開発および評価を行うためには，定性的な評価指標の定量化やユーザテストによる手法の評価などのアプローチが必要となる．本論文は，感性情報を考慮した人物画像処理の開発に関する上記課題について研究を行い，工学上の進歩に寄与することを目的とする．すなわち，人物写真や動画を対象として，①人物写真のもつ感性情報を評価する手法，並びに②感性情報を考慮し写真・動画を高品質化する手法を提案することで，感性情報を考慮した人物画像処理を開発するためのアプローチを示し，工学上の進歩に寄与することを目的とする．本論文は全 4 章により構成されている．
第 1 章を緒論とし，本論文の主題である感性情報を考慮した人物画像処理の開発について，人物写真および動画に関する利活用の現状とその関連研究，並びに今日までの研究状況を概観し，本研究の目的および本研究に対する筆者の立場を述べるとともに，本論文の内容について述べている．
第 2 章では，人物画像を構成する「人物領域」に着目し，人物写真の品質劣化要因となりうる「白飛び」の準定量評価について検討を加えている．具体的には，証明写真やプロフィール写真などに利用する人物写真の選定支援を目的として，顔画像における白飛びの準定量評価手法を提案した．11 名の評価者による主観評価と白飛びの準定量評価結果を比較したところ，提案手法は，顔画像の白飛びに対する準定量評価を可能にすることが明らかとなった．
第 3 章では，人物画像を構成する「背景領域」を別の画像に差し替える背景差し替え法に着目している．具体的には，背景差し替えにおける前景（人物領域）と新しい背景（風景画像）の光源色の違いに起因して生じる背景差し替え映像の違和感を軽減する手法を提案した．14 名による評価実験の結果，提案手法は色被りした風景画像を用いた背景差し替え映像に対する違和感軽減を可能にすることを明らかにした．
第 4 章は結論で，本研究で得られた主な成果と本論文の工学的意義および今後に残された課題について述べている
