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Pengaruh Ekstrak Etanol Jahe Merah terhadap Kadar Malondialdehida (MDA) Serum dan Otak Mencit Alzheimer yang di induksi Skopolamin
No full textPenyakit alzheimer merupakan salah satu jenis penyakit otak, dan merupakan bentuk demensia paling umum. Penyakit ini merupakan penyakit degeneratif yang semakin memburuk seiring berjalannya waktu. Penyakit alzheimer ditandai dengan adanya deposisi abnormal beta amiloid yang membentuk plak senile/pikun dan hiperfosforilasi protein tau menyebabkan pembentukan belitan neurofibril/neurofibrillary tangles. Plak beta amiloid menyebabkan kerusakan pada beberapa mekanisme seperti disfungsi mitokondria, akumulasi logam, hiperfosforilasi tau dan inflamasi. Kerusakan itu akan menghasilkan Reactive Oxygen Species (ROS) yang berlebih yang mengakibatkan stres oksidatif. stres oksidatif ini akan berkontribusi dalam akumulasi plak beta amiloid. Proses ini akan menjadi siklus dan akan memperparah perkembangan penyakit alzheimer. Radikal bebas seperti ROS menyerang agen oksigen tipe reaktif pada lipid terutama Polyunsaturated Fatty Acids (PUFA) yang akan menghasilkan beberapa produk oksidasi bergugus fungsi aldehida, salah satunya adalah malondialdehida (MDA). Oleh karena itu, MDA dapat digunakan sebagai indikator stres oksidatif. Namun, hingga saat ini obat yang digunakan untuk mengobati alzheimer hanya berfokus pada penghambatan asetilkolinesterase, antagonis reseptor N-methyl-D-aspartate (NMDA) atau kombinasi keduanya. Obat-obatan ini belum ada yang menargetkan untuk mengurangi radikal bebas pada tubuh dan masih dalam perkembangan, sedangkan penghilangan ROS atau pencegahan pembentukannya diketahui dapat menunda onset atau memperlambat perkembangan penyakit alzheimer. Ekstrak etanol jahe merah mengandung senyawa fenolik seperti gingerol dan shogaol, yang berperan dalam mencegah terjadinya stres oksidatif dan peradangan. Oleh karena itu, pengujian dilakukan pada model mencit alzheimer dengan pemberian induksi skopolamin yang merupakan obat standar yang dapat digunakan untuk menginduksi gangguan memori.
Penelitian ini bertujuan untuk mengetahui pengaruh pemberian ekstrak etanol jahe merah terhadap kadar malondialdehida (MDA) serum darah dan otak mencit alzheimer yang diinduksi skopolamin. Pengujian dilakukan pada 24 ekor mencit yang dibagi menjadi 6 kelompok yaitu kelompok normal (CMC-Na), kelompok negatif (CMC-Na), kelompok positif (Donepezil 3 mg/kgBB), serta kelompok ekstrak etanol jahe merah dosis 100, 200 dan 400 mg/kgBB. Selanjutnya, mencit diinjeksi dengan normal salin pada kelompok normal sedangkan kelompok lain diinjeksi skopolamin 1 mg/kgBB. Pemberian perlakuan dilakukan selama 15 hari, dengan pemberian induksi pada hari ke-8 sampai ke-15. Kemudian, pada hari ke-16 mencit dibedah untuk diambil serum darah dan otak. Serum darah dan otak diambil untuk diuji absorbansi pada panjang gelombang 532 nm untuk diketahui kadar MDA. Sebelumnya, perlu dilakukan pembuatan kurva baku menggunakan standar TEP. Data kadar MDA serum darah berupa rata-rata ± SD, diuji statistika menggunakan one way ANOVA dan dilanjutkan dengan uji LSD, sedangkan data kadar MDA otak diuji statistika menggunakan uji Kruskal-Wallis dan dilanjutkan dengan uji Mann-Whitney, dikarenakan data yang didapat terditribusi normal tetapi tidak homogen.
Hasil penelitian menunjukkan bahwa ekstrak etanol jahe merah dapat menurunkan kadar MDA serum dan otak pada mencit azheimer yang diinduksi skopolamin. Pemberian ekstrak etanol jahe merah dosis 100, 200 dan 400 mg/kgBB mampu menurunkan kadar MDA serum darah secara signifikan dibanding dengan kelompok negatif. Ekstrak etanol jahe merah 400 mg/kgBB diketahui mampu menurunkan kadar MDA otak paling baik dibandingkan dosis 100 mg/kgBB dan 200 mg/kgBB. Aktivitas dari ekstrak etanol jahe merah 400 mg/kgBB menunjukkan kadar MDA otak yang kecil dibandingkan kelompok normal, namun lebih besar dibandingkan donepezil sebagai kontrol positif. Hasil statistik menunjukkan pemberian ekstrak etanol jahe merah 400 mg/kgBB tidak memiliki perbedaan yang signifikan dibandingkan kelompok normal ataupun donepezil sebagai kontrol positif. Sehingga pada penelitian ini dapat disimpulkan bahwa ekstrak etanol 400 mg/kgBB merupakan dosis efektif jahe merah dari tiga tingkatan dosis yang dapat menurunkan kadar MDA serum darah dan otak mencit alzheimer yang diinduksi skopolamin.Dosen Pembimbing Utama : Dr. apt. Fifteen Aprila Fajrin, S.Farm., M.Farm
Dosen Pembimbing Anggota : apt. Ika Puspita Dewi, S.Farm., M.Biomed
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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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