1,720,971 research outputs found
Le Cellule endoteliali del cordone ombelicale hanno un destino cellulare che dipende dal sesso del feto
Full text linkAims: The endothelial cells (EC) play a crucial role in the regulation of a broad range of many physiological and pathological processes. The aims of this work are to evaluate possible gender differences in EC obtained by male and female newborn umbilical cord in cell fate and in the ability of cell survival in starvation an inducer of autophagy.
Methods: HUVECs (human umbilical vein endothelial cells) were isolated as previously described by Cheung L et al. and umbilical cord were provided by the department of Pharmacology, Gynecology, and Obstetrics by University of Sassari. The cell proliferation was evaluated with MTS assay kit and dimension and cell shape were evaluated with Labworks sofware. Moreover we determinate H2O2 LDH and PAI-1 concentration with commercial colorimetric assay kit respectively in cell supernatants and, eNOS, Beclin1, LC3, AKT, mTOR expression by western blotting on cell lysates according to the instructions provided by Cell Signalling Tecnology assay kit and nitrite quantification by Griess reaction on culture supernatants. The experiments were performed with the 5 passage.
Results: Basically, no significant differences are observed in cell shape and dimension, LDH, PAI-1 and nitrite and nitrate production levels and espression of eNOS. But basal male cells have a higher expression of Beclin1, an autophagic marker, while the expression of AKT and its activity as mTOR expression are significantly higher in female than in male cells. After 36 hours of starvation, as expected both cell types are more autophagic, but male cells shows significantly higher expression of ratio LC3II/LC3I, an autophagic activity indicator. Finally, both cell types have lower AKT and mTOR espression and both cells show no AKT activity.
Conclusion: When intracellular nutrients are limited as during starvation, eukaryotic cells can trigger a pathway of survival called autophagy. Here, it is evident that male and female endothelial cells have different responses
Statistical Analysis Applied to the Production of Mirto Liqueur
Full text linkPreparation of myrtle liqueur through ethanol-based extraction is a widely employed methodology. Nevertheless, optimization of existing processes is possible, especially through a modern statistical multivariate approach. In this context, a Design of Experiments (DoE) approach was used to quantitatively assess for the first time the effect of the time, ethanol concentration, temperature, and the ratio between the Myrtus communis berries’ weight and the extractant volume (v/w) on the amounts of anthocyanins, volatile compounds and dry residues in the liqueur. The kinetic profile relative to the volatile fraction variation during the process was described by gas chromatography (GC), while spectrophotometric analysis allowed quantification of the total anthocyanins and total polyphenols. Multiple response analysis showed that the maximum efficiencies in terms of the considered parameters (desirability function) were reached by setting the temperature to 25 °C and the ethanol percentage to 96% after 20 days of processing. Some hints as to the chemical instability and not negligible sensitivity of anthocyanins in relation to the experimental conditions for longer extraction times were also observed. The statistical model represents a novel tool for industrial production of myrtle liqueur
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
Profiling of the bioactive compounds in flowers, leaves and roots of vinca sardoa
No full textVinca sardoa (Stern) Pignatti (Apocynaceae) is largely distributed in Sardinia where it is considered a typical endemism. Since the plant is used in traditional folk medicine, the aim of the present work was to identify and quantify the polyphenolic metabolites, due to the well-known importance of polyphenolic compounds, as well as to evaluate antioxidant activity in different parts of the plant. The compounds were identified and determined in the methanol extracts of leaves, flowers, and roots by developing different LC-MS/MS methods. The obtained data show that leaves possess the highest amount of polyphenols, in particular quinic acid (3401 mg/100 g), chlorogenic acid (1082 mg/100 g), caffeoylquinic acid isomer 1 (190 mg/100 g), and robinin (633 mg/100 g). Likewise, antioxidant tests showed that leaves possess the main radical scavenging activities in both ABTS (49.19 ± 3.41 Î1⁄4g/mL, 30.88 ± 3.04 Î1⁄4g/mL at time zero and after 50 min, respectively) and DPPH assays (223.97 ± 30.81 Î1⁄4g/mL, 109.52 ± 12.89 Î1⁄4g/mL at time zero and after 30 min, respectively).Taking into account that leaves differed most from flowers and roots in the content of caffeoylquinic acid and chlorogenic acid, of which antioxidant properties are widely recognized, it is reasonable to assume that these two compounds are involved in the differences described. The relationship between the high polyphenolic content and interesting antioxidant activities, justifies its use in ethnobotany and may be suggest a use of this specie, after removal of the alkaloid fraction, in the pharmaceutical, phytotherapy, and cosmetic industries
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
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