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Effects of differential extraction of Verbena officinalis on rat models of inflammation, cicatrization and gastric damage
No full textPlanta Med. 2007 Mar;73(3):227-35. Epub 2007 Mar 12.
Effects of differential extraction of Verbena officinalis on rat models of inflammation, cicatrization and gastric damage.
Speroni E, Cervellati R, Costa S, Guerra MC, Utan A, Govoni P, Berger A, Müller A, Stuppner H.
Source
Dipartimento di Farmacologia, Università di Bologna, Bologna, Italy. [email protected]
Abstract
Verbena officinalis L. is used in folk medicine for the treatment of inflammatory disorders, skin burns, abrasions, and gastric diseases. Extracts obtained with different solvents (methanol, VoME; enriched flavonoids, VoEF; supercritical CO2, VoCO2) were evaluated for anti-inflammatory, gastroprotective and cicatrizing activities. Additionally, the antioxidant capacity was determined in vitro. In order to confirm the activities investigated, histological observations were performed. All extracts induce a remarkable anti-inflammatory activity. The gastric damage is significantly reduced by all extracts administered, whereby the most pronounced protection is observed for the VoCO2 and VoEF extracts. Finally, a wound healing effect is obtained particularly by the CO2 extract, suggesting the presence of some lipophilic active principles. Histological evidence confirms the results evaluated with the animal procedures. The results obtained after oral administration of V. officinalis extracts are also in agreement with the antioxidant capacity evaluated in vitro, confirming the relationship between pharmacological activities and antiradical efficacy
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
Phytochemical investigation and biological activity of Cyclamen repandum .
No full textAs part of a series of phytochemical investigations for bioactive compounds from medicinal plants we investigated Cyclamen repandum S. et S. (Primulaceae). The tubers of this plant were used in Sardinian folk medicine as abortive, others species of the genus are used in Turkish against infertility. Early investigation on the different species of genus resulted in the isolation of triterpenic saponins (1-3). At our knowledge no phytochemical and biological data are available about C. repandum. In this paper we report the chemical investigation, anti-inflammatory and anti-nociceptive activities of C. repandum tubers. The powdered tubers were extracted using solvents of increasing polariry (petroleum ether, chloroform and methanol). The residues were tested for the biological activities. The activities were evaluated “in vivo” with two experimental procedures: rat paw’s edema and writhing in mice. The results obtained with methanol extract indicate a significant reduction of edema, after oral administration of 75 mg/Kg of dried residue. As concerns the writhing test, a very significant decrease of the number of writhes was observed, after oral administration of 150 mg/Kg. As frequently natural active principles, endowed with anti-inflammatory activity exhibit antioxidant power, it seemed interesting to evaluate this capacity. For this purpose the same extracts were tested with Briggs-Rauscher reaction (4). No antioxidant power was recorded. Nevertheless the saponin content justifies the pharmacological results.
The active extract was fractionated using combined column chromathography (silica gel, Sephadex LH 20 and preparative HPLC). Five compounds were isolated. Compounds 1 and 2 were characterized by HR mass spectrometry, 1D and 2D NMR experiments as triterpenoid saponins, namely deglucocyclamin and deglucoanagalloside B. The structural elucidation of 3- 5 is in progress.
References: 1. Calis I. et al. (1997) Planta Med. 63, 166-170. 2. Calis I. et al. (1997) J.Nat.Prod. (1997). 60, 315-318. 3. Yayli N. et al. (1998) Planta Med. 64, 382-384. 4. Cervellati R. et al. (2002) J. Agric. Food Chem., 50, 7504-7509
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
Analgesic and antiinflammatory activity of Cyclamen repandum S. et S.
No full textAccording to folk medicine some species belonging to the genus Cyclamen were used for their biological
activities. Early investigation of the different species of the genus resulted in the isolation of triterpenic
saponins. No phytochemical and biological data are available on C. repandum. As part of a series of
phytochemical investigations for bioactive compounds from medicinal plants, Cyclamen repandum S. et S. was
investigated. The present study sought to find the antiinflammatory and antinociceptive activities of C. repandum
tubers in rats and mice. A preliminary screening was conducted with three different extracts in the tests used,
particularly the paw edema and the writhing tests. Subsequently some saponins isolated from the ME extract,
the more effective one, have been identified.
This paper also describes the results of fractionation and bioassay guided chemical studies. Chemical
investigation of the active extract afforded the isolation and characterization of six triterpenic saponins. The
possible antiinflammatory and analgesic properties were investigated as the saponin content of the fractions
allows to speculate on such aspect
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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