1,720,954 research outputs found
STUDI IN SILICO QUININ SEBAGAI KANDIDAT AGEN ANTI AGING: IN SILICO STUDY OF QUININE AS A CANDIDATE ANTI-AGING AGENT
Full text linkAging is a complex natural process and an inherent part of the life cycle. The continuous aging and accumulation of cells contribute to the degradation of the extracellular matrix, which further accelerates the aging process. Various topical agents have been utilized to combat aging, primarily through anti-aging treatments. Examples include the use of topical agents such as retinoids (retinol), vitamin C, hyaluronic acid, alpha hydroxy acids (AHA), and beta hydroxy acids (BHA). This study aims to explore the potential anti-aging properties of compounds found in the quinine-producing plants Cinchona ledgeriana (Ledger) and Cinchona succirubra (Succi) through a molecular approach using the molecular docking method to assess their activity against aging-related proteins. The tested ligands in this study include quinine, cinchonine, quinidine, and cinchonidine, with retinol as the antagonist ligand. In silico analysis suggests that quinine, cinchonine, quinidine, and cinchonidine from Cinchona ledgeriana (Ledger) and Cinchona succirubra (Succi) exhibit strong potential as anti-aging agents by targeting the proteins hyaluronidase receptor (1FCV), elastase (1Y93), collagenase (2D1N), tyrosinase (2Y9X), and HSP90 (5XRB). Molecular docking simulations using MOE 2015.10 revealed quinine\u27s superior binding affinity, with free energy values ranging from -4.9 to -6.8 kcal/mol across target proteins. Critical interactions with His263 (tyrosinase) and Asp206 (elastase)were identified through LigPlot analysis. The docking analysis confirmed the reliability of the methodology, demonstrating that quinine, quinidine, cinchonine, and cinchonidine strongly bind to key skin-ageing enzymes. This study demonstrates the potential of Cinchona bark-derived phytochemicals as anti-aging agents, with quinine exhibiting superior inhibitory activity against tyrosinase. Quinine demonstrated the strongest inhibition against tyrosinase (ΔG = -6.84 kcal/mol), outperforming reference ligands and other Cinchona alkaloids. These findings provide a scientific basis for further exploration of these compounds in mitigating skin aging and enhancing dermatological health.
Keywords: Antiaging, in silico, molecular docking, quininePenuaan merupakan proses alami kompleks yang merupakan bagian dari siklus hidup. Penuaan yang berlangsung terus-menerus serta akumulasi kematian sel berkontribusi pada degradasi matriks ekstraseluler, yang selanjutnya mempercepat proses penuaan. Berbagai agen topikal telah digunakan untuk melawan penuaan, terutama melalui perawatan anti-aging seperti retinoid (retinol), vitamin C, asam hialuronat, alpha hydroxy acids (AHA), dan beta hydroxy acids (BHA). Studi ini bertujuan untuk mengeksplorasi potensi anti-aging dari senyawa yang ditemukan pada tanaman kina, dengan spesies Cinchona ledgeriana (Ledger) dan Cinchona succirubra (Succi), melalui pendekatan molekuler menggunakan metode molecular docking untuk melihat aktivitasnya terhadap protein-protein yang berhubungan dengan penuaan. Ligan yang diuji dalam studi ini meliputi kina, sinkonin, kuinidin, dan sinkonidin, dengan retinol sebagai ligan antagonis. Analisis in silico menunjukkan bahwa kina, sinkonin, kuinidin, dan sinkonidin dari Cinchona ledgeriana dan Cinchona succirubra memiliki potensi kuat sebagai agen anti-aging dengan menargetkan protein reseptor hialuronidase (1FCV), elastase (1Y93), kolagenase (2D1N), tirosinase (2Y9X), dan HSP90 (5XRB). Analisis docking menunjukkan validitas metode dan reseptor yang digunakan, dan juga ligan uji kina, sinkonin, kuinidin, dan sinkonidin memiliki afinitas ikatan yang kuat terhadap enzim-enzim penting yang berperan dalam penuaan kulit. Studi ini menunjukkan potensi fitokimia dari kulit batang kina sebagai agen anti-aging karena memiliki aktivitas inhibisi kuat terhadap tirosinase. Penelitian ini memberikan dasar ilmiah untuk eksplorasi lebih lanjut terhadap senyawa-senyawa uji dalam mengurangi penuaan dan meningkatkan kesehatan kulit
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
Contract Farming through Tea-Horticulture Intercropping System: A Case Study of Gambung Estate and Horticultural Farmers in Bandung, Indonesia
Full text linkContract farming is becoming a viable form of partnership between tea plantation companies and local farmers in the management of tea plantations. This study aimed to: (1) describe a contract farming pattern through the system of intercropping tea-horticulture, (2) analyze the efficiency of the management of tea garden with contract farming, and (3) describe the benefits and sustainability of the contract farming between Gambung Estate and horticultural farmers. The case study was conducted in Gambung Estate using qualitative descriptive analysis and contract farming scheme analysis. The study observed that the contract farming patterns applied was a modified nucleus estate model with a combination of resource provisioning cooperation with production management cooperation. The challenges for future contract farming include land management, new skill transfer, climate change, and shared risk and effort between the two parties so that the bargaining position of horticultural farmers will be increased in the sustainable tea plantation management framework. Value of investment efficiency was 47 percent for new planting and 49 percent for replanting. The highest R/C and B/C values were given to the intercropping system of tea-chili at 2:25 and 1:25, respectively
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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