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951.
952.
Lo Vasco VR Fabrizi C Artico M Cocco L Billi AM Fumagalli L Manzoli FA 《Journal of cellular biochemistry》2007,100(4):952-959
Signal transduction from plasma membrane to cell nucleus is a complex process depending on various components including lipid signaling molecules, in particular phosphoinositides and their related enzymes, which act at cell periphery and/or plasma membrane as well as at nuclear level. As far as the nervous system may concern the inositol lipid cycle has been hypothesized to be involved in numerous neural as well as glial functions. In this context, however, a precise panel of glial PLC isoforms has not been determined yet. In the present experiments we investigated astrocytic PLC isoforms in astrocytes obtained from foetal primary cultures of rat brain and from an established cultured (C6) rat astrocytoma cell line, two well known cell models for experimental studies on glia. Identification of PLC isoforms was achieved by using a combination of RT-PCR and immunocytochemistry experiments. While in both cell models the most represented PI-PLC isoforms were beta4, gamma1, delta4, and epsilon, isoforms PI-PLC beta2 and delta3 were not detected. Moreover, in primary astrocyte cultures PI-PLC delta3 resulted well expressed in C6 cells but was absent in astrocytes. Immunocytochemistry performed with antibodies against specific PLC isoforms substantially confirmed this pattern of expression both in astrocytes and C6 glioma cells. In particular while some isoenzymes (namely isoforms beta3 and beta4) resulted mainly nuclear, others (isoforms delta4 and epsilon) were preferentially localized at cytoplasmic and plasma membrane level. 相似文献
953.
Gauthier DT Cartwright DD Densmore CL Blazer VS Ottinger CA 《Fish & shellfish immunology》2003,14(4):279-288
In this study we present a method for the measurement of in vitro mitogenesis in fish leucocytes that is based on the incorporation of the thymidine analogue 5'-bromo-2'-deoxyuridine (BrdU) into the DNA of replicating cells, followed by ELISA-based detection. This technique, adapted from methods developed for mammalian cells, operates on a similar biological principle to (3)H-thymidine incorporation, but circumvents the logistical and safety issues inherent with the radioactive label. Because it directly measures DNA proliferation, the assay has advantages over other colorimetric methods that may be strongly influenced by leucocyte metabolic status. Using BrdU incorporation followed by ELISA, we evaluate the responsiveness of rainbow trout (Oncorhynchus mykiss [Walbaum]) leucocytes to the mammalian T-cell mitogen Concanavalin A (Con A) as well as the differential response of white perch (Morone americana [Gmelin]) leucocytes to Con A and pokeweed mitogen. Specific considerations intrinsic to the assay system are discussed, including the implications of utilising enzyme-based detection. 相似文献
954.
The binding capacity of bovine beta-lactoglobulin variant A (beta-Lg A) for six peptides derived from beta-Lg was evaluated using an ultrafiltration method under the following conditions: pH 6.8, 40 degrees C, and a beta-Lg A/peptide molar ratio of 1:5. Only peptides beta-Lg f102-105, f142-148, and f69-83 bound in significant amounts to beta-Lg A corresponding to 1.5, 1.1, and 0.7 mol of peptide per mole of beta-Lg A, respectively. The interaction between beta-Lg A and the antihypertensive peptide beta-Lg f142-148 was investigated further by isothermal titration calorimetry. The binding isotherms at pH 6.8 and 25 degrees C confirmed that beta-Lg f142-148 bound to beta-Lg A and that the interaction followed a sequential three-site binding model with constants of association of 2 x 10(3), 1 x 10(3), and 0.4 x 10(3) M(-1) for the first, second, and third binding sites, respectively. The enthalpy of binding was exothermic for the first and second binding sites and endothermic for the third binding site. Binding of the peptide to all three sites was spontaneous as shown by the negative free energy values. These results show for the first time that beta-Lg A can bind bioactive peptides. This potential could be exploited to transport bioactive peptides and protect them in the gastrointestinal tract following their oral administration as nutraceuticals. 相似文献
955.
Venturini MC Venturini L Bacigalupe D Machuca M Echaide I Basso W Unzaga JM Di Lorenzo C Guglielmone A Jenkins MC Dubey JP 《International journal for parasitology》1999,29(10):1705-1708
Antibodies to Neospora caninum were measured in bovine foetuses, dairy cows and beef cows in Argentina using the IFAT, the N. caninum agglutination test, and the recombinant NCDG1 and NCDG2 ELISA. Serum antibodies (IFAT titre 1:80) were found in 20 of 82 (24.4%) dairy cow foetuses and one of 22 (4.5%) beef cow foetuses. Microscopic lesions suggestive of neosporosis were seen in brains of seven of eight foetuses with IFAT titres of 1:80. Antibodies (IFAT) were found in 122 of 189 (64.5%) dairy cows that aborted. Serum antibody titres (IFAT) of 189 dairy cows that aborted were: < 1:25 (67 cows), 1:25 (four cows), 1:50 (16 cows), 1:200 (seven cows), 1:> or = 800 (95 cows). Of the 87 sera with IFAT titres of < or = 1:50, 57 had no antibodies in 1:40 dilution and 30 had titres of 1:40 in the N. caninum agglutination test. Thus, sera from at least 56 dairy cows which had aborted were seronegative both in the N. caninum agglutination test and the IFAT. The distribution of positive and negative sera was similar when measured by ELISA, except that, depending on cut-off titre, the ELISA indicated a greater number of seropositive cows that were negative by the IFAT and N. caninum agglutination test. These results suggest that transplacental transmission of N. caninum in dairy cows in Argentina is frequent. 相似文献
956.
Giuseppe Gugliotta Mauro Botta Giovanni Battista Giovenzana Lorenzo Tei 《Bioorganic & medicinal chemistry letters》2009,19(13):3442-3444
Novel bifunctional agents based on the AAZTA (6-amino-6-methylperhydro-1,4-diazepinetetraacetic acid) structure with hydroxyl, carboxyl and chloro functional groups were prepared. The GdIII complexes show optimal magnetic properties making them very good candidates for conjugation to biomolecules for molecular imaging applications. An example of conjugation to a bile acid derivative is also reported. 相似文献
957.
Fabrication of multi‐well chips for spheroid cultures and implantable constructs through rapid prototyping techniques 下载免费PDF全文
958.
959.
Emily S. Darling Lorenzo Alvarez‐Filip Thomas A. Oliver Timothy R. McClanahan Isabelle M. Côté 《Ecology letters》2012,15(12):1378-1386
Classifying the biological traits of organisms can test conceptual frameworks of life‐history strategies and allow for predictions of how different species may respond to environmental disturbances. We apply a trait‐based classification approach to a complex and threatened group of species, scleractinian corals. Using hierarchical clustering and random forests analyses, we identify up to four life‐history strategies that appear globally consistent across 143 species of reef corals: competitive, weedy, stress‐tolerant and generalist taxa, which are primarily separated by colony morphology, growth rate and reproductive mode. Documented shifts towards stress‐tolerant, generalist and weedy species in coral reef communities are consistent with the expected responses of these life‐history strategies. Our quantitative trait‐based approach to classifying life‐history strategies is objective, applicable to any taxa and a powerful tool that can be used to evaluate theories of community ecology and predict the impact of environmental and anthropogenic stressors on species assemblages. 相似文献
960.
Permanent Genetic Resources added to Molecular Ecology Resources Database 1 April 2012 - 31 May 2012
Molecular Ecology Resources Primer Development Consortium P Abelló W Ai C Altmann G Bernardi O Bonato KM Burchhardt X Chen Z Chen D Cížková C Clouet MA Cubeta V Garcia-Merchan N Gauthier S Gibson K Halačka F Hamdi T Hankeln A Hochkirch T Hrbek AM Jackson C Lin SM Lin E Macpherson J Macrander E Marešová J Mendel M Nowak G Orti F Palero I Papoušek M Pascual T Schmitt BX Semmens JC Streito EW Tian SP Tseng M Veith L Vetešník HY Wang J Weyer S Willis H Yu Z Zhou 《Molecular ecology resources》2012,12(5):972-974
This article documents the addition of 123 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Brenthis ino, Cichla orinocensis, Cichla temensis, Epinephelus striatus, Gobio gobio, Liocarcinus depurator, Macrolophus pygmaeus, Monilinia vaccinii-corymbosi, Pelochelys cantorii, Philotrypesis josephi, Romanogobio vladykovi, Takydromus luyeanus and Takydromus viridipunctatus. These loci were cross-tested on the following species: Cichla intermedia, Cichla ocellaris, Cichla pinima, Epinephelus acanthistius, Gobio carpathicus, Gobio obtusirostris, Gobio sp. 1, Gobio volgensis, Macrolophus costalis, Macrolophus melanotoma, Macrolophus pygmaeus, Romanogobio albipinnatus, Romanogobio banaticus, Romanogobio belingi, Romanogobio kesslerii, Romanogobio parvus, Romanogobio pentatrichus, Romanogobio uranoscopus, Takydromus formosanus, Takydromus hsuehshanesis and Takydromus stejnegeri. 相似文献