1,721,025 research outputs found
Phytochemical and biological studies of Stachys species in relation to chemotaxonomy: A review
No full textThe genus Stachys is comprised of about 300 species spread throughout the world, hence representing one of the largest genera of the Lamiaceae. Several Stachys species have been exploited in traditional medicine as astringent, wound-healing, anti-diarrhoeal, anti-nephritic and anti-inflammatory agents. Moreover, antimicrobial, antioxidant and cytotoxic activities of some Stachys species are documented. Iridoids, flavonoids, phenolic acids and diterpenoids are reported as secondary metabolites of different species of this genus. The aim of the present review is to summarize and to highlight the recent advances in current knowledge on Stachys species and to compile reports of chemical constituents isolated from the genus Stachys over the past decades, together with their structural features, biological activities, and structure-activity relationships. Diversity of chemical constituents is discussed in relationship with current Stachys infra-generic taxonomy, classification and relationships with systematically close genera
Citrus medica L. cv Diamante (Rutaceae) peel extract improves glycaemic status of Zucker diabetic fatty (ZDF) rats and protects against oxidative stress
No full textThis study aimed to investigate the antidiabetic, antilipidaemic and antioxidant activities of Citrus medica cv Diamante (Rutaceae) hydroalcoholic (CD) peel extract in Zucker diabetic fatty (ZDF) rats. The ability of CD to protect against oxidative stress was investigated by using different in vitro assays and in vivo by using the reactive oxygen metabolites-derived compounds (d-ROMs) test and the biological antioxidant potential test (BAP). Two different doses of CD extract (300 and 600 mg/kg/die) were administered at ZDF rats for 4 weeks. CD reduced cholesterol and triglycerides levels. A dose-dependent effect on body weight and serum glucose levels was observed. A decrease of d-ROMs and an increase of BAP were recorded by using the dose of 600 mg/kg. The extract inhibited lipid peroxidation (IC50 value of 0.23 mg/ml). These findings suggest as an efficient phytotherapeutic approach in combating hyperlipidaemic and hyperglycaemic disorders
Flavonoids targeting NRF2 in neurodegenerative disorders
No full textNeurodegenerative disorders are characterized by progressive loss of neurons. To date, no efficacious therapies exist for these disorders, and current therapies provide only symptomatic relief. The neuroprotective effects of natural compounds have been reported in several neurological disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) amyotrophic lateral sclerosis (ALS), cerebral ischemia and brain tumors. Flavonoids are the most widely studied natural products for the prevention and treatment of neurodegenerative disorders. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) represents a complex gene regulated cytoprotective pathway. Several natural compounds have been identified as Nrf2 regulators in various chronic disorders, including carcinogenic, liver ailments, inflammatory conditions, neurodegeneration, diabetes and cardiotoxicities. The current review focuses on Nrf2 targeting by flavonoids in the prevention and treatment of neurodegenerative disorders, addressing the most contemporary information available on this timely subject
Evaluation of fatty acids and biogenic amines profiles in mullet and tuna roe during six months of storage at 4 °C
No full textThe aim of this study was to monitor the fatty acids and biogenic amines (BAs) profiles in mullet (MugilCephalus) and tuna (Thunnus thynnus) roe (bottarga) during storage (0–180 days) at 4 8C. Fatty acids wereanalyzed by gas chromatography (GC) as methyl ester derivatives while BAs were investigated usingreverse-phase liquid chromatography (RP-LC) as dansyl derivatives. The content of total fatty acidsdecreased with time in mullet bottarga (BM) while in tuna bottarga (BT) the PUFA value showed a slightdecrease up to 30 days followed by an intense reduction after 90 and 180 days. An increasing content ofBAs was observed with time in all investigated samples without reaching hazardous concentrations. Ingeneral, the BAs concentrations were in decreasing order: tyramine, putrescine, cadaverine andhistamine. In BM, phenylethylamine was always present, representing a possible discriminatingcompound as it was absent in tuna bottarga at any time of storage. A Pearson correlation matrix showedthat lipid and protein degradation products were strongly and significantly correlated over theconsidered storage time implying that lipid oxidation processes are in some way linked to the chemicalproduction of BAs
Bioassay-guided fractionation of Euphrasia pectinata Ten. and isolation of iridoids with antiproliferative activity
No full textThe use of aerial parts of Euphrasia pectinata Ten. usually known as Eyebright, is one of the commonest
folk remedy in many European and Asian countries to treat eye problems. By a bioassay-guided
fractionation of the dichloromethane fraction of E. pectinata methanolic extract, following the
antiproliferative activity on different cancer cell lines (MCF-7, HeLa, LNCaP, ACHN and C32), the new
iridoid euphrasin (1), and the known campsinol (2), artselaenin A (3), and artselaenin B (4) were isolated.
The structure of euphrasin (1) was determined by spectroscopic methods. All compounds screened by
SRB assay exhibited antiproliferative activity in a concentration dependent-manner. In particular,
euphrasin (1) showed a promising activity against LNCaP and HeLa cells with IC50 values of 0.1 and
0.2 mM, respectively. Signficative results were also obtained with campsinol (2) with IC50 value of 1.9 mM
on endometrial cancer cells
Influence of packaging conditions on biogenic amines and fatty acids evolution during 15 months storage of a typical spreadable salami ('Nduja)
No full textThe study evaluated the fatty acids and the biogenic amines (BAs) in ‘Nduja of Spilinga stored in differentpackaging materials (i.e. natural casing under vacuum, glass jar, aluminum tube and OVTENE) during15 months of shelf-life. Raw materials and pepper mixture were analysed as well. BAs concentrationsincreased with time, tyramine (TYR), putrescine (PUT) and cadaverine (CAD) were the most abundant.BAs in natural casing were always higher than those found in glass jar, aluminum tube and OVTENE.Total fatty acids were characterized by higher level of unsaturated fatty acid that decreased with time(glass jar > natural casing under vacuum > aluminum tube > OVTENE). The reduction of PUFA is the consequenceof the increase of peroxides and carbonyls reacting with amino acids to form BAs. This was confirmedby Pearson’s correlation matrices implying that lipid oxidation processes were in some way linkedto the chemical production of BAs
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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