1,720,982 research outputs found
Protective effect of verbascoside in activated C6 glioma cells: possible molecular mechanisms
No full textDualistic Properties of Cosmetic Formulations Based on Phenylpropanoids from Ajuga Reptans
No full textOur continued interest in the research and development of cosmetic active ingredients deriving from natural sources, led us to investigate the potential of a purified extract of Ajuga reptans, a plant belonging to the family Labiatae known for its traditional use in skin healing. The extracts derives from a biotechnology platform componed by meristematic cell colture, developed in the frame of a NTFP (non timber forest product) project, an is characterized by high content in phenylpropanoid, of which teupolioside represents the majority component. The latter is a phenylpropanoid glucoside, structurally correlated echinacoside, known in the literature for the antioxidant properties. This study was conducted with the purpose of evaluating the applicability of the Ajuga reptans extract within different cosmetic formulations. In particular Photochemiluminescence (PCL) was used to proof the antioxidant capacity of cosmetic formulations containing the product, in relation to the change of the title of teupolioside. Furthermore, UVA and UVB filtering properties were also investigated. The results of the study showed relevant antioxidant capacity of the finished formulation against superoxide anion, the main reactive oxygen species, responsible for skin aging and significant synergic capacities to filter UV radiatio
Epidermal growth factor promotes uncoupling from the adenylate cyclase of the human D2 receptor expressed in GH4C1 cells
No full textNerve growth factor suppresses the transforming phenotype of human prolactinomas
No full textThe most effective therapy of human prolactinomas is represented by dopamine D-2 receptor agonists; there is, however, a population of nonresponder patients who require surgical intervention. In the present study, we report that prolactinomas totally resistant to pharmacological therapy have a high potential of both growing in soft agar and forming tumors in nude mice and lack D-2 receptors for dopamine. These tumors express the receptors for nerve growth factor (NGF) and are sensitive to its differentiating activity. After exposure to NGF for 4 days, prolactinoma cells decreased their proliferation rate, lost their capability to form colonies in soft agar, lost their tumorigenic activity in nude mice, and reexpressed the lactotroph-specific D-2 receptor protein inhibiting prolactin release. These effects were permanent after NGF withdrawal and were reproducible in vivo in nude mice transplanted with the tumors. NGF in fact remarkably and lastingly depressed tumor growth and induced expression of D-2 receptors when injected intravenously once a day for 5 days into prolactinoma-bearing nude mice. These data suggest that NGF may induce a long-lasting switch of gene expression in human prolactinomas, modifying their transforming phenotype and reverting them to more differentiated, less malignant, dopamine-sensitive lactotroph-like cells. The possibility thus arises that short-term treatment with NGF may restore the refractory patients to conventional pharmacological therapy with D-2 agonists
Nerve growth factor in the anterior pituitary: localization in mammotroph cells and co-secretion with prolactin by a dopamine-regulated mechanism
No full textNerve growth factor directs differentiation of the bipotential cell line GH-3 into the mammotroph phenotype
No full textGH-3 is an established cell line which, for the production of both PRL and GH, may be related to the bipotential somatomammotroph from which both somatotroph and mammotroph cells derive. In the present study we first report that GH-3 cells express both the gp140trk and the gp75 components of the nerve growth factor (NGF) receptor and that NGF dictates a nonneuronal type of differentiation of this cell line of ectodermal origin. After exposure to NGF, GH-3 cells markedly decreased their proliferation rate. This effect, which was maximal (50% inhibition) 3 days after beginning the treatment and was maintained during the following days of exposure, was paralleled by a change in the hormone production. The secretion of PRL was increased 6-fold, but that of GH was remarkably inhibited. Moreover, GH-3 cells expressed the mammotroph-specific D-2 receptor protein in response to NGF, as shown by binding with the D-2 receptor ligand N-(p-aminophenetyl)spiperone coupled to fluorescein. The present data thus show that NGF induces the differentiation of GH-3 cells into one of their physiological counterparts, the mammotroph cell, and together with the finding that NGF receptors are expressed in the anterior pituitary suggest a physiological role for the neurotrophic factor in pituitary ontogenesis
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
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