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CYTOCHROME P450-DEPENDENT MONOXYGENASE ACTIVITIES AND THEIR INDUCIDILITY BY CLASSICAL P450 INDUCERS IN THE LIVER, KIDNEY AND NASAL MUCOSA OF MALE ADULT RING-NECKED PHEASANTS
No full textCytochrome P450-Dependent Monooxygenase Activities and
Their Inducibility by Classic P450 Inducers in the Liver, Kidney,
and Nasal Mucosa of Male Adult Ring-Necked Pheasants. Giorgi
M., Marini S., Longo V., Mazzaccaro A., Amato G., and Gervasi
P. G. (2000). Toxicol. Appl. Pharmacol. 167, 237–245.
In this study, several P450-dependent monoxygenase activities
in the liver, kidney, and nasal mucosa of ring-necked pheasants
were examined. In addition, the presence and inducibility of P450
isoenzymes in the hepatic and renal tissues of pheasants were
examined by using typical substrates and inducers of P450s along
with polyclonal antibodies raised against mammalian isoforms.
Anti-rat P450 1A1 recognized in microsomes of both pheasant
liver and kidney a protein that was markedly induced by b-naphthoflavone
and accompanied by an increase of various monooxygenases,
in particular, methoxyresorufin-O-demethylase (MROD)
activity. Anti-rat P450 2E1 revealed in microsomes of the pheasant
liver but not in kidney an immunoreactive protein that was
slightly induced by acetone but not accompanied by an increase of
para-nitrophenol hydroxylase activity. On the other hand, acetone
treatment caused an induction of other hepatic monoxygenases
including MROD, erythromycin N-demethylase, and 6b-testosterone
hydroxylase. These two latter activities, known to be markers
for 3A isoenzymes in rodents, were also enhanced in pheasant liver
by phenobarbital but not by dexamethasone. The treatment with
these two inducers also lacked to point out hepatic and renal
proteins immunorelated to P450 3A or 2B subfamily, suggesting
that these isoforms may be not expressed in pheasant. On the other
hand, anti-rat P450 2C11 recognized two immunorelated proteins
in the liver of both control and treated pheasants. The treatment
with clofibrate, a mammalian inducer of 4A subfamily, induced
both in liver and kidney of pheasant: i) a protein that cross-reacted
with anti rat P450 4A1 and ii) the (v) and (v21) lauric acid
hydroxylase activities, known to be associated in mammals to this
P450 subfamily. In the nasal mucosa of pheasant, a protein immunorelated
to P450 2A and some monooxygenase activities (i.e.,
7-ethoxycoumarin O-deethylase) linked, in mammals, to this isoform
have been found; by contrast a protein immunoreactive with
anti P450 2G1 was not found. In conclusion, the immunochemical
properties and monooxygenase activities of constitutive and inducible
P450s in pheasants were different not only from those of
mammals but also from those of chickens. The findings of the
present work also suggest that the P450 induction profiles might
provide a potential biomarker of pheasant exposure to chemicals or environmental pollutants in the wild-field or in the stock-farm
Mutagenicity of hexahydrophenanthrenes and their oxirane derivatives
No full textThe mutagenicity of some hexahydrophenanthrenes and their corresponding arene oxides was assayed in histidine-dependent mutants of Salmonella typhimurium TA98 and TA100. All the arene epoxides examd. were devoid of mutagenic activity, although some of them could alkylate nicotinamide. By contrast, the 1,2,3,9,10,10a-hexahydrophenanthrene, trans-1,2,3,4,4a,10a-hexahydrophenanthrene, 9-methyl- and 6-methoxy-trans-1,2,3,4,4a,10a-hexahydrophenanthrene, 7-bromo-trans-1,2,3,4,4a,10a-hexahydrophenanthrene and 9-methyl-trans-1,2,3,4,4a,10a-hexahydrophenanthrene were active as mutagen
EFFECTS OF ?-NF ON P450 SYSTEM, P450 1A AND PHASE II ENZYMES OF [Ah] BATTERY IN GILTHEAD SEABREAM (Sparus aurata)
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
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