131 research outputs found

    Linguistic Politeness Beyond Modernity. A Critical Reconsideration of Politeness Theories

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    EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Advanced Java-based application to process thermoluminescence digital color images

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    Dielectric minerals that interact with ionizing radiation emit thermoluminescence when heated. The color of the emitted thermoluminescence varies among different samples, even for the same minerals. TL color analysis can be used to study mineral provenance. Thermoluminescence color images (TLCI) can be obtained using a digital camera. Inagaki et al. (2010) created a Java application to handle RGB (red-green-blue) information of each pixel. This Java application is able to visually represent thermoluminescence color on a CIE (Commission Internationale de l’Eclairage) chromaticity diagram. Here, we report an improved Java application that enables the numerical treatment of TLCI of various image sizes and resolutions. This application allows for the handling of many digital TLCI in a short time and it is useful for statistical color analyses

    Successful implantation after reducing matrix metalloproteinase activity in the uterine cavity

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    BACKGROUND: Recently, the concept of recurrent implantation failure (RIF) in assisted reproductive technology has been enlarged. Chronic uterine inflammation is a known cause of implantation failure and is associated with high matrix metalloproteinase (MMP) activity in uterine cavity flushing. MMP activity of women with RIF has been reported to be higher than that of fertile women. In the present retrospective study we evaluated the efficacy of treatment for high MMP activity in the uterine cavity of patients with RIF. METHODS: Of the 597 patients recruited to the study, 360 patients underwent MMP measurements and 237 patients did not (control group). All patients had failed to become pregnant, despite at least two transfers of good-quality embryos. Gelatinase MMP-2 and MMP-9 activity in uterine flushing fluid was detected by enzymology (MMP test). All samples were classified into two groups (positive or negative) based on the intensity of the bands on the enzyme zymogram, which represents the degree of MMP activity. Patients who tested positive on the initial test were treated for 2 weeks with a quinolone antibiotic and a corticosteroid, and subsequently underwent a second MMP test. Negative results on the second MMP tests after treatment and subsequent rates of pregnancy and miscarriage were used to evaluate the efficacy of treatment. Data were analyzed by the Mann–Whitney U-test and the chi-square test. RESULTS: Of the patients who underwent the MMP test, 15.6% had positive results (high MMP activity). After treatment, 89.3% of patients had negative results on the second MMP test. These patients had a significantly better pregnancy rate (42.0%) than the control group (26.6%), as well as a lower miscarriage rate (28.5% vs 36.5%, respectively). CONCLUSIONS: A 2-week course of antibiotics and corticosteroids effectively improves the uterine environment underlying RIF by reducing MMP activity

    Protein phosphatase 4 catalytic subunit regulates Cdk1 activity and microtubule organization via NDEL1 dephosphorylation

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    Protein phosphatase 4 catalytic subunit (PP4c) is a PP2A-related protein serine/threonine phosphatase with important functions in a variety of cellular processes, including microtubule (MT) growth/organization, apoptosis, and tumor necrosis factor signaling. In this study, we report that NDEL1 is a substrate of PP4c, and PP4c selectively dephosphorylates NDEL1 at Cdk1 sites. We also demonstrate that PP4c negatively regulates Cdk1 activity at the centrosome. Targeted disruption of PP4c reveals disorganization of MTs and disorganized MT array. Loss of PP4c leads to an unscheduled activation of Cdk1 in interphase, which results in the abnormal phosphorylation of NDEL1. In addition, abnormal NDEL1 phosphorylation facilitates excessive recruitment of katanin p60 to the centrosome, suggesting that MT defects may be attributed to katanin p60 in excess. Inhibition of Cdk1, NDEL1, or katanin p60 rescues the defective MT organization caused by PP4 inhibition. Our work uncovers a unique regulatory mechanism of MT organization by PP4c through its targets Cdk1 and NDEL1 via regulation of katanin p60 distribution

    Purification, Characterization and Crystal Structure of Isoamylase from Thermophilic Bacteria Rhodothermus marinus

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    The isoamylase gene from Rhodothermus marinus was cloned into and expressed in Escherichia coli Top 10. As a result of characterization of purified R. marinus isoamylase. the enzyme had an optimum pH of 4.0 and optimum temperature of 70℃. Thermal inactivation studies of the purified R. marinus isoamylase revealed the enzymatic activity to be uninfluenced after one hour incubation at 60℃. These results suggest that R. marinus isoamylase has high thermostability. The crystallization and crystal structure analysis of R. marinus isoamylase was performed. The three-dimensional structure at 1.9Å resolution was determined in complex with the panose. R. marinus isoamylase is composed of three domains N, A and C, and, has a (β/α)8-barrel in domain A. The secondary structural alignments of the R. marinus isoamylase and P. amyloderamosa isoamylase was carried out. They have the four active-site consensus regions characteristic of the α-amylase family. And the essential residue of the α-amylase family (D359, E395, and D467) was conserved in these enzymes. R. marinus isoamylase has shorter loops than P. amyloderamosa isoamylase. And R. marinus isoamylase had no Ca2+ binding site. These results are thought to be factors of thermostability of R. marinus isoamylase.Rhodothermus marinus 由来イソアミラーゼ遺伝子を組み込んだプラスミド pBX2を使用し,大腸菌 Top10株を形質転換し,16時間の前培養,24時間の本培養後,菌体破砕し,得られた無細胞抽出液を熱処理(80℃,10 min),50オ硫安分画,陰イオン交換カラムクロマトグラフィー(DEAEントヨパール),ハイドロキシアパタイトカラムクロマトグラフィーに供して本酵素の精製を行った.本精製酵素の性質検討を行った結果,本酵素の最適反応温度は70℃,pH4であり,また本酵素は60℃で1時間処理しても活性が低下することが無く,Pseudomonas amyloderamosa 由来イソアミラーゼよりも高い耐熱性を有することが判明した.本酵素の結晶化・X線結晶構造解析を行った結果,本酵素は P. amyloderamosa 由来イソアミラーゼと同様Nドメイン・AドメインCドメインの3つのドメインから構成されており,活性残基(D359,E395,D467)など活性中心付近のアミノ酸残基も P. amyloderamosa 由来イソアミラーゼと同様,高度に保存されていた.本酵素の熱安定性が P. amyloderamosa 由来イソアミラーゼよりも高 い要因として,P. amyloderamosa 由来イソアミラーゼよりもループの長さが全体的に短いことと,カルシウムイオン結合サイトの欠如が挙げられた.今後さらに構造解析を進めることにより,本酵素の熱安定性機構,反応 機構など更なる知見が得られることが期待される

    Lack of impact of the ALDH2 rs671 variant on breast cancer development in Japanese BRCA1/2‐mutation carriers

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    The aldehyde degrading function of the ALDH2 enzyme is impaired by Glu504Lys polymorphisms (rs671, termed A allele), which causes alcohol flushing in east Asians, and elevates the risk of esophageal cancer among habitual drinkers. Recent studies suggested that the ALDH2 variant may lead to higher levels of DNA damage caused by endogenously generated aldehydes. This can be a threat to genome stability and/or cell viability in a synthetic manner in DNA repair-defective settings such as Fanconi anemia (FA). FA is an inherited bone marrow failure syndrome caused by defects in any one of so far identified 22 FANC genes including hereditary breast and ovarian cancer (HBOC) genes BRCA1 and BRCA2. We have previously reported that the progression of FA phenotypes is accelerated with the ALDH2 rs671 genotype. Individuals with HBOC are heterozygously mutated in either BRCA1 or BRCA2, and the cancer-initiating cells in these patients usually undergo loss of the wild-type BRCA1/2 allele, leading to homologous recombination defects. Therefore, we hypothesized that the ALDH2 genotypes may impact breast cancer development in BRCA1/2 mutant carriers. We genotyped ALDH2 in 103 HBOC patients recruited from multiple cancer centers in Japan. However, we were not able to detect any significant differences in clinical stages, histopathological classification, or age at clinical diagnosis across the ALDH2 genotypes. Unlike the effects in hematopoietic cells of FA, our current data suggest that there is no impact of the loss of ALDH2 function in cancer initiation and development in breast epithelium of HBOC patients
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