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  1. Article ; Online: Synthesis and fluorescence properties of butadiyne-linked linear and cyclic carbazole oligomers.

    Ogawa, Kazuya / Tanaka, Shohei / Shimura, Kyosuke

    RSC advances

    2020  Volume 10, Issue 16, Page(s) 9657–9662

    Abstract: Butadiyne-linked linear and cyclic carbazole oligomers were successfully synthesized. The intensity of the emission band in the 0-0 band of the highly planar macrocyclics decreased compared to that of the 0-1 band. Contrary to this, for larger ... ...

    Abstract Butadiyne-linked linear and cyclic carbazole oligomers were successfully synthesized. The intensity of the emission band in the 0-0 band of the highly planar macrocyclics decreased compared to that of the 0-1 band. Contrary to this, for larger macrocycles having reduced planarity, the intensity of the emission of the 0-0 band increased as in the cases of the linear compounds. This suggests that the emission color of the π-conjugated molecule can be controlled not only by the difference between the cyclic and chain structures but also by the control of the planarity, and is expected to be a new principle for molecular design in the development of fluorescent materials.
    Language English
    Publishing date 2020-03-06
    Publishing country England
    Document type Journal Article
    ISSN 2046-2069
    ISSN (online) 2046-2069
    DOI 10.1039/d0ra00830c
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Unsupervised Predominant Sense Detection and Its Application to Text Classification

    Attaporn Wangpoonsarp / Kazuya Shimura / Fumiyo Fukumoto

    Applied Sciences, Vol 10, Iss 6052, p

    2020  Volume 6052

    Abstract: This paper focuses on the domain-specific senses of words and proposes a method for detecting predominant sense depending on each domain. Our Domain-Specific Senses (DSS) model is an unsupervised manner and detects predominant senses in each domain. We ... ...

    Abstract This paper focuses on the domain-specific senses of words and proposes a method for detecting predominant sense depending on each domain. Our Domain-Specific Senses (DSS) model is an unsupervised manner and detects predominant senses in each domain. We apply a simple Markov Random Walk (MRW) model to ranking senses for each domain. It decides the importance of a sense within a graph by using the similarity of senses. The similarity of senses is obtained by using distributional representations of words from gloss texts in the thesaurus. It can capture large semantic context and thus does not require manual annotation of sense-tagged data. We used the Reuters corpus and the WordNet in the experiments. We applied the results of domain-specific senses to text classification and examined how DSS affects the overall performance of the text classification task. We compared our DSS model with one of the word sense disambiguation techniques (WSD), Context2vec, and the results demonstrate our domain-specific sense approach gains 0.053 F1 improvement on average over the WSD approach.
    Keywords domain-specific sense ; Markov Random Walk ; text classification ; word sense disambiguation ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
    Subject code 006
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: A prospective multicenter study of endoscopic ultrasound-guided fine needle biopsy using a 22-gauge Franseen needle for pancreatic solid lesions.

    Ishigaki, Kazunaga / Nakai, Yousuke / Sasahira, Naoki / Sugimori, Kazuya / Kitamura, Katsuya / Iwai, Tomohisa / Matsubara, Saburo / Shimura, Kenji / Itoi, Takao / Ryozawa, Shomei / Ushio, Jun / Doi, Shinpei / Imazu, Hiroo / Maetani, Iruru / Isayama, Hiroyuki

    Journal of gastroenterology and hepatology

    2021  Volume 36, Issue 10, Page(s) 2754–2761

    Abstract: Background and aim: While encouraging data of endoscopic ultrasound (EUS)-guided fine-needle biopsy (EUS-FNB) using a 22-gauge Franseen needle have been reported, large-scale data of per pass and quantitative analyses are still lacking.: Methods: ... ...

    Abstract Background and aim: While encouraging data of endoscopic ultrasound (EUS)-guided fine-needle biopsy (EUS-FNB) using a 22-gauge Franseen needle have been reported, large-scale data of per pass and quantitative analyses are still lacking.
    Methods: This was a multicenter prospective study of EUS-FNB using the 22-gauge Franseen needle for a pancreatic solid lesion. Cytological and histological analyses per pass were evaluated and semi-quantitative analyses were performed on core tissue and blood contamination. Primary end-point was diagnostic accuracy per session. Prognostic factors were analyzed for diagnostic accuracy, sensitivity, core tissue, and blood contamination.
    Results: A total of 629 passes were performed in 244 cases at 14 centers between 2018 and 2019. The median tumor size was 29 mm, and the puncture was transduodenal in 43%. The median pass number was 2. Diagnostic accuracy per session, at a first pass, and per pass were 93%, 90%, and 88%. In 198 cases with pancreatic cancer, diagnostic sensitivity per session, at a first pass, and per pass were 94%, 89%, and 89%. The rates of core tissue score of 4 and blood contamination score of 3 were 50% and 47%. The adverse event rate was 1.6%. In the multivariate analysis, tumor size ≤20 mm (odds ratio [OR] of 0.46, P = 0.03), transduodenal puncture (OR of 0.53, P = 0.04), and suction (OR of 0.16, P = 0.01) were associated with lower diagnostic accuracy.
    Conclusions: The EUS-FNB using the 22-gauge Franseen needle for pancreatic solid lesions showed high per pass and overall diagnostic accuracy.
    MeSH term(s) Endoscopic Ultrasound-Guided Fine Needle Aspiration ; Humans ; Needles ; Pancreas/diagnostic imaging ; Pancreatic Neoplasms/diagnostic imaging ; Prospective Studies
    Language English
    Publishing date 2021-05-14
    Publishing country Australia
    Document type Journal Article ; Multicenter Study
    ZDB-ID 632882-9
    ISSN 1440-1746 ; 0815-9319
    ISSN (online) 1440-1746
    ISSN 0815-9319
    DOI 10.1111/jgh.15534
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Human retroviral antisense mRNAs are retained in the nuclei of infected cells for viral persistence.

    Ma, Guangyong / Yasunaga, Jun-Ichirou / Shimura, Kazuya / Takemoto, Keiko / Watanabe, Miho / Amano, Masayuki / Nakata, Hirotomo / Liu, Benquan / Zuo, Xiaorui / Matsuoka, Masao

    Proceedings of the National Academy of Sciences of the United States of America

    2021  Volume 118, Issue 17

    Abstract: Human retroviruses, including human T cell leukemia virus type 1 (HTLV-1) and HIV type 1 (HIV-1), encode an antisense gene in the negative strand of the provirus. Besides coding for proteins, the messenger RNAs (mRNAs) of retroviral antisense genes have ... ...

    Abstract Human retroviruses, including human T cell leukemia virus type 1 (HTLV-1) and HIV type 1 (HIV-1), encode an antisense gene in the negative strand of the provirus. Besides coding for proteins, the messenger RNAs (mRNAs) of retroviral antisense genes have also been found to regulate transcription directly. Thus, it has been proposed that retroviruses likely localize their antisense mRNAs to the nucleus in order to regulate nuclear events; however, this opposes the coding function of retroviral antisense mRNAs that requires a cytoplasmic localization for protein translation. Here, we provide direct evidence that retroviral antisense mRNAs are localized predominantly in the nuclei of infected cells. The retroviral 3' LTR induces inefficient polyadenylation and nuclear retention of antisense mRNA. We further reveal that retroviral antisense RNAs retained in the nucleus associate with chromatin and have transcriptional regulatory function. While HTLV-1 antisense mRNA is recruited to the promoter of C-C chemokine receptor type 4 (
    MeSH term(s) Basic-Leucine Zipper Transcription Factors/genetics ; Basic-Leucine Zipper Transcription Factors/metabolism ; Cell Line ; Cell Nucleus/metabolism ; Gene Expression/genetics ; Gene Expression Regulation, Viral/genetics ; HIV-1/genetics ; Human Immunodeficiency Virus Proteins/genetics ; Human Immunodeficiency Virus Proteins/metabolism ; Human T-lymphotropic virus 1/genetics ; Humans ; Primary Cell Culture ; Promoter Regions, Genetic/genetics ; Proviruses/genetics ; RNA, Antisense/genetics ; RNA, Antisense/metabolism ; RNA, Messenger/metabolism ; RNA, Viral/genetics ; Retroviridae Proteins/genetics ; Retroviridae Proteins/metabolism ; Terminal Repeat Sequences/genetics ; Transcription, Genetic/genetics ; Viral Envelope Proteins/genetics ; Viral Envelope Proteins/metabolism ; Viral Proteins/metabolism ; Virus Latency/genetics ; Virus Replication/genetics
    Chemical Substances ASP protein, HIV-1 ; Basic-Leucine Zipper Transcription Factors ; HBZ protein, human T-cell leukemia virus type I ; Human Immunodeficiency Virus Proteins ; RNA, Antisense ; RNA, Messenger ; RNA, Viral ; Retroviridae Proteins ; Viral Envelope Proteins ; Viral Proteins
    Language English
    Publishing date 2021-11-18
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2014783118
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Impact of HIV-1 infection pathways on susceptibility to antiviral drugs and on virus spread.

    Shimura, Kazuya / Miyazato, Paola / Oishi, Shinya / Fujii, Nobutaka / Matsuoka, Masao

    Virology

    2015  Volume 484, Page(s) 364–376

    Abstract: The infection routes of HIV-1 can affect several viral properties, including dissemination, pathogenesis, and immune evasion. In this study, we evaluated the inhibitory activity of a wide variety of anti-HIV drugs, focusing on the impact that different ... ...

    Abstract The infection routes of HIV-1 can affect several viral properties, including dissemination, pathogenesis, and immune evasion. In this study, we evaluated the inhibitory activity of a wide variety of anti-HIV drugs, focusing on the impact that different infection pathways have on their efficacy. Compared to cell-free infection, inhibitory activities were reduced in cell-to-cell productive transmission for all drugs tested. We detected weak reporter-expressing target cells after cell-to-cell transmission in the presence of integrase strand transfer inhibitors (INSTIs). Further analysis revealed that this expression was mainly due to unintegrated circular HIV (cHIV) DNAs, consisting of 1-LTR and 2-LTR circles. When in vitro-constructed cHIV DNAs were introduced into cells, the production of infectious and intercellular transmittable virions was observed, suggesting that cHIV DNA could be a source of infectious virus. These results highlight some advantages of the cell-to-cell infection mode for viral expansion, particularly in the presence of anti-retroviral drugs.
    MeSH term(s) Anti-HIV Agents/pharmacology ; Cell Line ; HIV-1/drug effects ; HIV-1/physiology ; Humans ; Virus Internalization/drug effects ; Virus Release/drug effects ; Virus Replication/drug effects
    Chemical Substances Anti-HIV Agents
    Language English
    Publishing date 2015-07-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 200425-2
    ISSN 1096-0341 ; 0042-6822
    ISSN (online) 1096-0341
    ISSN 0042-6822
    DOI 10.1016/j.virol.2015.06.029
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Elvitegravir: a new HIV integrase inhibitor.

    Shimura, Kazuya / Kodama, Eiichi N

    Antiviral chemistry & chemotherapy

    2009  Volume 20, Issue 2, Page(s) 79–85

    Abstract: Integration is a distinctive and essential process in the HIV infection cycle and thus represents an attractive antiviral drug target. Integrase inhibitors combined with other classes of drug might contribute to long-lasting suppression of HIV type-1 ( ... ...

    Abstract Integration is a distinctive and essential process in the HIV infection cycle and thus represents an attractive antiviral drug target. Integrase inhibitors combined with other classes of drug might contribute to long-lasting suppression of HIV type-1 (HIV-1) replication for many patients. Of the numerous potential integrase inhibitor leads that have been reported, few have reached clinical trials and only one, raltegravir, has been approved (in late 2007) for the treatment of HIV-1-infected patients. Another integrase inhibitor, elvitegravir, is currently showing promise in Phase III clinical studies. Once-daily administration of elvitegravir has a comparable antiviral activity to twice-daily of raltegravir in HIV-1-infected patients. Here, we highlight the salient features of elvitegravir: its chemical structure compared with representative integrase inhibitors, mechanism of action, in vitro and in vivo activity against HIV and other retroviruses, and the effect of integrase polymorphisms and resistance mutations on its anti-HIV activity.
    MeSH term(s) Drug Resistance, Neoplasm/genetics ; HIV Integrase Inhibitors/chemistry ; HIV Integrase Inhibitors/pharmacology ; Humans ; Quinolones/chemistry ; Quinolones/pharmacology ; Retroviridae/drug effects
    Chemical Substances HIV Integrase Inhibitors ; Quinolones ; elvitegravir (4GDQ854U53)
    Language English
    Publishing date 2009-10-19
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 1033586-9
    ISSN 2040-2066 ; 0956-3202
    ISSN (online) 2040-2066
    ISSN 0956-3202
    DOI 10.3851/IMP1397
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Correction: HTLV-1 bZIP Factor Enhances T-cell Proliferation by Impeding the Suppressive Signaling of Co-inhibitory Receptors.

    Kinosada, Haruka / Yasunaga, Jun-Ichirou / Shimura, Kazuya / Miyazato, Paola / Onishi, Chiho / Iyoda, Tomonori / Inaba, Kayo / Matsuoka, Masao

    PLoS pathogens

    2017  Volume 13, Issue 2, Page(s) e1006228

    Abstract: This corrects the article DOI: 10.1371/journal.ppat.1006120.]. ...

    Abstract [This corrects the article DOI: 10.1371/journal.ppat.1006120.].
    Language English
    Publishing date 2017-02-23
    Publishing country United States
    Document type Published Erratum
    ZDB-ID 2205412-1
    ISSN 1553-7374 ; 1553-7366
    ISSN (online) 1553-7374
    ISSN 1553-7366
    DOI 10.1371/journal.ppat.1006228
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Sporadic on/off switching of HTLV-1 Tax expression is crucial to maintain the whole population of virus-induced leukemic cells.

    Mahgoub, Mohamed / Yasunaga, Jun-Ichirou / Iwami, Shingo / Nakaoka, Shinji / Koizumi, Yoshiki / Shimura, Kazuya / Matsuoka, Masao

    Proceedings of the National Academy of Sciences of the United States of America

    2018  Volume 115, Issue 6, Page(s) E1269–E1278

    Abstract: Viruses causing chronic infection artfully manipulate infected cells to enable viral persistence in vivo under the pressure of immunity. Human T-cell leukemia virus type 1 (HTLV-1) establishes persistent infection mainly in CD4+ T cells in vivo and ... ...

    Abstract Viruses causing chronic infection artfully manipulate infected cells to enable viral persistence in vivo under the pressure of immunity. Human T-cell leukemia virus type 1 (HTLV-1) establishes persistent infection mainly in CD4+ T cells in vivo and induces leukemia in this subset. HTLV-1-encoded Tax is a critical transactivator of viral replication and a potent oncoprotein, but its significance in pathogenesis remains obscure due to its very low level of expression in vivo. Here, we show that Tax is expressed in a minor fraction of leukemic cells at any given time, and importantly, its expression spontaneously switches between on and off states. Live cell imaging revealed that the average duration of one episode of Tax expression is ∼19 hours. Knockdown of Tax rapidly induced apoptosis in most cells, indicating that Tax is critical for maintaining the population, even if its short-term expression is limited to a small subpopulation. Single-cell analysis and computational simulation suggest that transient Tax expression triggers antiapoptotic machinery, and this effect continues even after Tax expression is diminished; this activation of the antiapoptotic machinery is the critical event for maintaining the population. In addition, Tax is induced by various cytotoxic stresses and also promotes HTLV-1 replication. Thus, it seems that Tax protects infected cells from apoptosis and increases the chance of viral transmission at a critical moment. Keeping the expression of Tax minimal but inducible on demand is, therefore, a fundamental strategy of HTLV-1 to promote persistent infection and leukemogenesis.
    MeSH term(s) Gene Expression Regulation, Viral ; Gene Products, tax/genetics ; Gene Products, tax/metabolism ; HTLV-I Infections/genetics ; HTLV-I Infections/metabolism ; HTLV-I Infections/virology ; Human T-lymphotropic virus 1/pathogenicity ; Humans ; Leukemia-Lymphoma, Adult T-Cell/genetics ; Leukemia-Lymphoma, Adult T-Cell/metabolism ; Leukemia-Lymphoma, Adult T-Cell/virology ; Single-Cell Analysis ; T-Lymphocytes/virology ; Virus Activation ; Virus Replication
    Chemical Substances Gene Products, tax ; tax protein, Human T-lymphotrophic virus 1
    Language English
    Publishing date 2018-01-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.1715724115
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Impaired oxidative endoplasmic reticulum stress response caused by deficiency of thyroid hormone receptor α.

    Takahashi, Kazuya / Furuya, Fumihiko / Shimura, Hiroki / Kaneshige, Masahiro / Kobayashi, Tetsuro

    The Journal of biological chemistry

    2014  Volume 289, Issue 18, Page(s) 12485–12493

    Abstract: Thyroid hormone receptor α (TRα) is critical to postnatal pancreatic β-cell maintenance. To investigate the association between TRα and the survival of pancreatic β-cells under endoplasmic reticulum (ER) stress, the expression of endogenous TRα was ... ...

    Abstract Thyroid hormone receptor α (TRα) is critical to postnatal pancreatic β-cell maintenance. To investigate the association between TRα and the survival of pancreatic β-cells under endoplasmic reticulum (ER) stress, the expression of endogenous TRα was inhibited by infection with an adenovirus expressing double-stranded short hairpin RNA against TRα (AdshTRα). In control adenovirus-infected pancreatic β-cells, palmitate enhanced the expression of activating transcription factor 4 (ATF4) and heme oxygenase 1, which facilitates adaptation to oxidative ER stress. However, in AdshTRα-infected pancreatic β-cells, palmitate did not induce ATF4-mediated integrated stress response, and oxidative stress-associated apoptotic cell death was significantly enhanced. TRα-deficient mice or wild-type mice (WT) were fed a high fat diet (HFD) for 30 weeks, and the effect of oxidative ER stress on pancreatic β-cells was analyzed. HFD-treated TRα-deficient mice had high blood glucose levels and low plasma insulin levels. In HFD-treated TRα-deficient mice, ATF4 was not induced, and apoptosis was enhanced compared with HFD-treated WT mice. Furthermore, the expression level of 8-hydroxydeoxyguanosine, an oxidative stress marker, was enhanced in the β-cells of HFD-treated TRα-deficient mice. These results indicate that endogenous TRα plays an important role for the expression of ATF4 and facilitates reduced apoptosis in pancreatic β-cells under ER stress.
    MeSH term(s) 8-Hydroxy-2'-Deoxyguanosine ; Activating Transcription Factor 4/genetics ; Activating Transcription Factor 4/metabolism ; Animals ; Apoptosis/drug effects ; Apoptosis/genetics ; Apoptosis/physiology ; Blood Glucose/metabolism ; Blotting, Western ; Cell Line, Tumor ; Deoxyguanosine/analogs & derivatives ; Deoxyguanosine/metabolism ; Diet, High-Fat ; Dietary Fats/pharmacology ; Endoplasmic Reticulum Stress/genetics ; Endoplasmic Reticulum Stress/physiology ; Immunohistochemistry ; Insulin/blood ; Insulin-Secreting Cells/drug effects ; Insulin-Secreting Cells/metabolism ; Insulinoma/genetics ; Insulinoma/metabolism ; Insulinoma/pathology ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Oxidative Stress ; Pancreatic Neoplasms/genetics ; Pancreatic Neoplasms/metabolism ; Pancreatic Neoplasms/pathology ; RNA Interference ; Reverse Transcriptase Polymerase Chain Reaction ; Thyroid Hormone Receptors alpha/deficiency ; Thyroid Hormone Receptors alpha/genetics
    Chemical Substances Atf4 protein, mouse ; Blood Glucose ; Dietary Fats ; Insulin ; Thyroid Hormone Receptors alpha ; Activating Transcription Factor 4 (145891-90-3) ; 8-Hydroxy-2'-Deoxyguanosine (88847-89-6) ; Deoxyguanosine (G9481N71RO)
    Language English
    Publishing date 2014-03-18
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.M113.544122
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Correction

    Haruka Kinosada / Jun-Ichirou Yasunaga / Kazuya Shimura / Paola Miyazato / Chiho Onishi / Tomonori Iyoda / Kayo Inaba / Masao Matsuoka

    PLoS Pathogens, Vol 13, Iss 2, p e

    HTLV-1 bZIP Factor Enhances T-cell Proliferation by Impeding the Suppressive Signaling of Co-inhibitory Receptors.

    2017  Volume 1006228

    Abstract: This corrects the article DOI:10.1371/journal.ppat.1006120.]. ...

    Abstract [This corrects the article DOI:10.1371/journal.ppat.1006120.].
    Keywords Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
    Language English
    Publishing date 2017-02-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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