112,035 research outputs found
Effects of beta-naphtoflavone on P450 system, P450 1A and phase II enzymes of [Ah] battery in gilthead seabream (Sparus aurata)
No full textEffect of clofibrate, a peroxisome proliferator, in sea bass (Dicentrarchus labrax), a marine fish
No full textThe effects of 35 or 70 mg/kg clofibrate on some peroxisomal, mitochondrial, and microsomal enzymes (markers of peroxisome proliferation) in liver, gill, and kidney of sea bass following 2 weeks i.p. treatment have been studied, Induction of lauric acid hydroxylase, UDP-glucuronyl transferase, palmitoyl-CoA oxidase, carnitine-palmitoyl-transferase, p-nitrophenylacetate hydrolase, and benzaldehyde and propionaldehyde dehydrogenase activities was not observed in any case. The clofibrate administration at the dose of 70 mg/kg induced in the liver the glutathione S-tranferase and reduced epoxide hydrolase activities. These results demonstrate that a marine fish species, such as sea bass, is rafractary to peroxisome proliferation. (C) 1999 Academic Press
author-bios-SRD-19-0063.R1 – Supplemental material for The Network Structure of Police Misconduct
No full textSupplemental material, author-bios-SRD-19-0063.R1 for The Network Structure of Police Misconduct by George Wood, Daria Roithmayr and Andrew V. Papachristos in Socius</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
No full text“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
Sperm quality assessment in Ficopomatus enigmaticus (Fauvel, 1923): Effects of selected organic and inorganic chemicals across salinity levels
No full textContamination by organic and inorganic compounds remains one of the most complex problems in both brackish and marine environments, causing potential implications for the reproductive success and survival of several broadcast spawners. Ficopomatus enigmaticus is a tubeworm polychaete that has previously been used as a model organism for ecotoxicological analysis, due to its sensitivity and ecological relevance. In the present study, the effects of five trace elements (zinc, copper, cadmium, arsenic and lead), one surfactant (sodium dodecyl sulfate, SDS) and one polycyclic aromatic hydrocarbon (benzo(a)pyrene, B(a)P) on the sperm quality of F. enigmaticus were investigated. Sperm suspensions were exposed in vitro to different concentrations of each selected contaminant under four salinity conditions (10, 20, 30, 35). Possible adverse effects on sperm function were assessed by measuring oxidative stress, membrane integrity, viability and DNA damage. Sperm quality impairments induced by organic contaminants were more evident than those induced by inorganic compounds. SDS exerted the largest effect on sperm. In addition, F. enigmaticus sperm showed high tolerance to salinity variation, supporting the wide use of this species as a promising model organism for ecotoxicological assays. Easy and rapid methods on polychaete spermatozoids were shown to be effective as integrated sperm quality parameters or as an alternative analysis for early assessment of marine and brackish water pollution
Presence and inducibility by Beta-naphthoflavone of CYP1A1, CYP1B1 and phase II enzymes in Trematomus bernacchii, an Antarctic fish
No full textThis study investigated some aspects of xenobiotic metabolism in the Nototheniidae Trematomus bernacchii, a key sentinel species for monitoring Antarctic ecosystems. After laboratory exposure to beta-naphthoflavone (beta NF), basal levels and time-course induction of CYP1A, CYP1B and CYP3A were measured as enzymatic activities, immunoreactive protein content and mRNA expression in liver, gills, intestine and heart. Additional analyses in the liver included enzymatic activities of testosterone hydroxylase, (omega)- and (omega - 1)-lauric acid hydroxylase and some phase II enzymes related to the AhR battery genes, DT-diaphorase, glutathione S-transferases and UDP-glucuronyl transferases. Responsiveness of hepatic CYP1A1 after exposure to PNF demonstrated an higher sensitivity of MEROD than EROD activity and long lasting expression of mRNA still induced after 20 days from the treatment. Testosterone metabolism, oxidation of lauric acid and activities of phase II enzymes were not affected by PNF indicating that their modulation is not mediated by Ah receptor. Induction of CYP1A was more limited in gills and absent in intestine and heart. The first nucleotide sequence for CYP1B1 in an Antarctic fish has been obtained, revealing a homology of 89% and 72% respectively to CYP1B1 of plaice and CYP1B2 of carp. Constitutive expression of CYP1B1 was restricted to gills where it was also induced by beta NE Obtained results represent an additional contribution to the ecotoxicological characterization of T bernacchii and further support the use of biomarkers for early detection of chemical pollution in Antarctica. (c) 2007 Elsevier B.V. All rights reserved
Bioaccumulation and ecotoxicological responses of clams exposed to terbium and carbon nanotubes: Comparison between native (Ruditapes decussatus) and invasive (Ruditapes philippinarum) species
No full textIn the last decades the use of rare earth elements (REEs) increased exponentially, including Terbium (Tb) which has been widely used in newly developed electronic devices. Also, the production and application of nanoparticles has been growing, being Carbon Nanotubes (CNTs) among the most commonly used. Accompanying such development patterns, emissions towards the aquatic environments are highly probable, with scarce information regarding the potential toxicity of these pollutants to inhabiting species, especially considering their mixture. In the present study the effects of Tb and CNTs exposure (acting alone or as a mixture) on native and invasive clams´ species (Ruditapes decussatus and Ruditapes philippinarum, respectively) were evaluated, assessing clams´ accumulation and metabolic capacities, oxidative status as well neurotoxic impacts. Results obtained after a 28-days exposure period showed that the accumulation of Tb in both species was not affected by the presence of the CNTs and similar Tb concentrations were found in both species. The effects caused by Tb and CNTs, acting alone or as a mixture induced greater alterations in R. philippinarum antioxidant capacity in comparison to native R. decussatus, but no cellular damages were observed in both species. Nevertheless, although metabolic impairment was only observed in clams exposed to Tb, loss of redox balance and neurotoxicity were evidenced by both species regardless the exposure treatment. These findings highlight the potential impacts caused by CNTs and Tb, which may affect clams´ normal physiological functioning, impairing their reproduction and growth capacities. The obtained results point out the need for further investigation considering the mixture of pollutants.Fil: Sturla Lompre, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. Universidade de Aveiro; PortugalFil: Moleiro, Pedro. Universidade de Aveiro; PortugalFil: De Marchi, Lucia. Interuniversity Consortium of Marine Biology of Leghorn "G. Bacci"; Italia. University of Pisa. Department of Biology; ItaliaFil: Soares, Amadeu M.V.M.. Universidade de Aveiro; PortugalFil: Pretti, Carlo. Interuniversity Consortium of Marine Biology of Leghorn "G. Bacci"; Italia. University of Pisa. Department of Veterinary Sciences; ItaliaFil: Chielini, Federica. University of Pisa. Department of Chemistry and Industrial Chemistry; ItaliaFil: Pereira, Eduarda. Universidade de Aveiro; PortugalFil: Freitas, Rosa. Universidade de Aveiro; Portuga
Antimicrobial susceptibility of Staphylococcus intermedius and Staphylococcus schleiferi isolated from dogs
No full textThe susceptibility to 23 antimicrobial agents was determined in 114 isolates of Staphylococcus intermedius and eight isolates of Staphylococcus schleiferi of canine origin. Overall, 73% of S. intermedius isolates and 37.5% of S. schleiferi isolates were susceptible to all the 23 antimicrobials tested. The large majority of S. intermedius strains retained susceptibility to antimicrobials currently employed in treatment of pyoderma (cephalosporins, cotrimoxazole and association amoxicillin-clavulanic acid) as well as to those effective against staphylococci (fusidic acid, rifampicin and fluoroquinolones). Resistance in S. intermedius was observed mainly against macrolides, chloramphenicol and lincosamides, while S. schleiferi isolates retained susceptibility to all antimicrobials except three of six fluoroquinolones. Although, our results confirm susceptibility to antimicrobials currently employed in pyoderma treatment, the several different resistance patterns observed for S. intermedius emphasize the importance of antimicrobial susceptibility testing of canine staphylococci to choose the most appropriate treatment of infections and to allow the prudent use of antimicrobial drugs in companion animals. (C) 2009 Elsevier Ltd. All rights reserved
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