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Signaling transduction pathway of TGF-β1 and its effect on differention of human dental pulp cell
No full text實驗目的：轉型生長因子(Transforming growth factor-beta, TGF-β) 對於牙髓組織的修復與牙本質生成扮演重要的角色。本實驗的目的在於探討TGF-β1所誘導的訊息傳導途徑以及TGF-β1對牙髓細胞生長分化所造成影響的機制。驗方法：使用TGF-β1對人類牙髓細胞做刺激，在某些實驗中則先加入U0126，Noggin，SB431542 等抑制劑做前處理。另外以西方點墨法(Western Blot Analysis)，MTT 測定，反轉錄鏈聚合反應(RT-PCR)，鹼性磷酸酶染色 (ALP staining)，膠原蛋白定量測定(Sircol Collagen Assay) 來觀察我們的發現。驗結果：在西方點墨法的分析中，TGF-β1會誘導下游的ERK, Smad 2/3, Smad 1/5/8 等訊息的活化。藉由Smad 2的訊息傳導途徑，TGF-β1 (5 ng/ml & 10 ng/ml) 會抑制人類牙髓細胞的細胞存活率與鹼性磷酸酶的活性。透過反轉錄鏈聚合反應的實驗可以發現TGF-β1 (5 ng/ml & 10 ng/ml) 會造成ALP 與Runx-2的基因表現都有下降的趨勢。TGF-β1 (5 ng/ml)也會促進牙髓細胞中膠原蛋白的合成。這些影響在使用U0126 (MEK/ERK抑制劑)，Noggin (Smad 1/5/8抑制劑)做前處理的組別中沒有看到顯著的改變。但在使用SB431542作前處理的組別中可看到TGF-β1的作用有被抑制的現象。論：TGF-β1在人類牙髓細胞中的訊息傳導是複雜的，除了傳統的Smad 2/3之外，還包括了Smad1/5/8，ERK等途徑。透過Smad 2/3的途徑TGF-β1可能抑制細胞內的ALP，Runx-2的表現並提高膠原蛋白的合成，此作用與牙髓的修復與牙本質的再生有某種程度的影響。Aim: Transforming growth factor β1 (TGF-β1) plays a role in repair and dentinogenesis in dental pulp cells. The purpose of this study is to investigate whether TGF-β1 stimulates the two signaling pathways, MEK/ERK and Smad2 to mediate Runx2 expression, collagen matrix deposition and alkaline phosphatase in human dental pulp cells.aterials and Methods: Primary-cultured human dental pulp cells were treated with TGF-β1. in some experiments, cells were pretreated with U0126 (a MEK/ERK inhibitor), Noggin (a BMP antagonist), or SB431542 (an ALK5/ Smad 2/3 inhibitor) 30 minutes before adding TGF-β1. Signaling of TGF-β1 was investigated by western-blot assay. Cell proliferation was evaluated by MTT assay. Cell differentiation and mineralization was evaluated by alkaline phosphatase (ALP) staining. Changes in mRNA expression were determined by reverse-transcriptase polymerase chain reaction (RT-PCR). Collagen content was determined by Sircol Collagen assay.esults: In human dental pulp cell, TGF-β1 induce the expression of ERK, Smad 2, Smad 1/5/8 signaling. Cell under the treatment of TGF-β1 (5 ng/ml & 10 ng/ml) showed a decrease in ALP activity and gene expression of ALP and Runx-2. TGF-β1 (5 ng/ml) induced collagen formation in dental pulp cell. Pretreatment of U0126 (a MEK/ERK inhibitor) and Noggin (a Smad 1/5/8 inhibitor) was not effective to prevent these events. SB431542 (an ALK5/ Smad 2/3 inhibitor) attenuate the TGF-β 1-induced decline of ALP activity and Runx-2 expression. In conclusion, TGF-β1 down-regulates Runx-2 and ALP activity of human dental pulp cells via ALK5/Smad2/3 signaling.onclusion: Signal transduction of TGF-β1 in human dental pulp cell is complex. In addition to the well-known Smad2/3 pathway, Smad 1/5/8 and MAPK/ERK also take part in this complex system. These events are crucial in the mechanism of pulpal repair and regeneration.中文摘要.......1bstract.......3hapter I Literature Review..5.1 Reparative mechanism of pulpal-dentin complex.......5.2 Transforming Growth Factor –beta superfamily.8.2.1 TGF-β superfamily....8.2.2 TGF-β isoforms and their peptide structure.....9.2.3 TGF-β in dental pulp.9.3 Receptors of TGF-β...11.4 Signal transduction pathways of TGF-β1........12.4.1 Ligand binding & Receptor recruitment.12.4.2 Smad Phosphorylation & Co-mad binding.....13.4.3 Translocation into nucleus & DNA transcription.......13.4.4 I-Smads..14.4.5 TGF-β & MAPK pathway...14.5 Regulation of Alkaline phosphatase (ALP) and its role in tissue mineralization..15.5.1 Alkaline phosphatase.15.5.2 Regulation of ALPase..16.6 Runx2 and its role in cell differention.....17hapter II The purposes of the study.19hapter III Materials & Methods.....20.1 Materials..20.2 Culture of human dental pulp cells.20.3 Effect of TGF-β on human dental pulp cells...21.4 Alkaline phosphatase (ALP) staining......21.5 Reverse Transcription Polymerse Chain Reaction (RT-PCR)........22.5.1 Isolation of total RNA.23.5.2 RNA Quantitation....24.5.3 Reverse transcription (RT)..24.5.4 Polymerase Chain Reaction (PCR).......25.6 Western Blot Analysis.27.6.1 Sample preparation..27.6.2 Protein Concentration Determination...27.6.3 Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE)...28.6.4 Western Blot..28.7 MTT assay........30.8 Collagen Content Assay.....30.9 Statistical analysis.....32hapter IV Results..33.1 Morphological observation on human dental pulp cell.33.2 Signaling transduction pathways on human dental pulp cell by TGF-β1 - western blot analysis.......33.3 Effect of TGF-β1 on cell viability of pulp cells- MTT assay.......34.4 Effect of TGF-β1 on ALP activity of pulp cells......35.5 Effect of TGF-β1 on ALP activity of pulp cells and its modulation by SB431542, Noggin and U0126.36.6 Effect of TGF-β1 on ALP and Runx-2 mRNA expression of pulp cells..37.7 Effect of SB431542 on the TGF-β1-induced alterations of ALP and Runx-2 expression in dental pulp cells..37.8 Effect of TGF-β1 on type I collagen formation of dental pulp cell and its modulation by SB431542, Noggin and U0126.....38hpater V Discussion.......39hapter VI Conclusion......44eferences...4
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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