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PRODUZIONE DI METABOLITI SECONDARI DI ORIGINE VEGETALE A PARTIRE DA COLTURE IN VITRO DI CALLI DALLA POLPA DI FRUTTA DI DIVERSE POMACEAE (VALUTAZIONE DELL’ATTIVITÀ BIOLOGICA DEI METABOLITI SECONDARI OTTENUTI DA COLTURE IN VITRO DI CELLULE DI POLPA DI CALLO)
No full textThis doctoral thesis focused on evaluating the biological activities of hydroalcoholic extracts derived from callus pulp cultures of three selected apples: Cydonia oblonga Mill., Mela Rosa Marchigiana, and Malus pumila cv Miller (Annurca Campana Apple).
For each apple, the research followed the following workflow: (1) establishment of callus cultures and extract preparation, (2) qualitative-quantitative chemical characterization of SM extracts, and (3) evaluation of their biological activity.
In Cydonia oblonga Mill., the hydroalcoholic extract, previously found to be rich in phenolic and triterpenic compounds, demonstrated a potent anti-inflammatory effect in in vitro models of LPS-stimulated RAW 264.7 macrophages and HaCaT keratinocytes. Results indicated significant reductions in NO production, and pro-inflammatory gene expression (iNOS, IL-6, IL-1β, ikBα, ICAM). Moreover, the extract reduced the radical oxygen species levels in the hydrogen peroxide (H2O2) and tert-butyl hydroperoxide- (TBHP) injured HaCaT keratinocytes, revealing an important antioxidant activity.
For Mela Rosa Marchigiana, callus cultures from sub-cultures maintained high triterpenic acid content and bioactivity over the years. Comparative analysis with previous extracts confirmed consistent antioxidant, and anti-inflammatory effects, as demonstrated through cell-free (DPPH, ABTS, and ORAC) and cell-based assays (LPS-stimulated RAW 264.7 macrophages and H2O2 injured HaCaT keratinocytes).
In Malus pumila cv Miller, two callus cultures were cultivated under darkness and photoperiod conditions. The selected conditions for generating the two types of calli facilitated the production of substantial amounts of triterpenic compounds. Both calli primarily exhibit anti-inflammatory and genoprotective effects (tested using the lipoxygenase inhibition activity assay and LPS-stimulated RAW 264.7 macrophages, and the nicking assay, respectively) while showing lower antioxidant activity (evaluated by DPPH, ABTS, and ORAC assays). The callus cultivated in light conditions was chosen for encapsulation in a nanocarrier, which allowed for the assessment of its anti-inflammatory activity in a cellular model of ferroptosis on HaCaT cells. The results highlight the promise of Annurca Apple Callus extract in addressing oxidative stress and inflammation linked to excess iron. The nanocarrier system greatly improves its therapeutic effectiveness, as evidenced by gene expression analysis showing that the encapsulated extract can modulate the expression of genes associated with the ferroptosis process (COX-2, GPX-4, NrF2, IL-6, and TNF-α).
Overall, this study highlights the potential of callus culture technology for producing bioactive SMs with pharmaceutical, cosmetic, and nutraceutical applications. It also emphasizes the importance of optimizing culture conditions and leveraging advanced delivery systems to maximize the therapeutic potential of plant-derived compounds. These findings pave the way for scalable and sustainable production strategies in bioactive compound research and industry applications
Cydonia oblonga Mill. Pulp Callus Inhibits Oxidative Stress and Inflammation in Injured Cells
Get PDFThe pharmacological activity of a callus extract from the pulp of Cydonia oblonga Mill., also known as quince, was investigated in murine macrophage (RAW 264.7) and human keratinocyte (HaCaT) cell lines. In particular, the anti-inflammatory activity of C. oblonga Mill. pulp callus extract was assessed in lipopolysaccharides (LPS)-treated RAW 264.7 by the Griess test and in LPS-treated HaCaT human keratinocytes by examining the expression of genes involved in the inflammatory process, including nitric oxide synthase (iNOS), interleukin-6 (IL-6), interleukin-1β (IL-1β), nuclear factor-kappa-B inhibitor alfa (ikBα), and intercellular adhesion molecule (ICAM). The antioxidant activity was evaluated by quantizing the reactive oxygen species (ROS) production in the hydrogen peroxide and tert-butyl hydroperoxide-injured HaCaT cell line. The obtained results indicate that C. oblonga callus from fruit pulp extract has anti-inflammatory and antioxidant activities, suggesting its possible application in delaying and preventing acute or chronic diseases associated with aging or in the treatment of wound dressing. © 2023 by the authors
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
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