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OBJECTIVE: To evaluate molecular abnormalities in the c-kit gene of canine mast cell tumors (MCT) with different grades of cellular differentiation. SAMPLE POPULATION: 31 normal tissue specimens from dogs and 45 canine MCT classified according to grade of cell differentiation. PROCEDURES: Genomic DNA extractions were made from canine MCT and normal tissues. Parts of exon 11, intron 11, and exon 12 of the c-kit gene were amplified by use of polymerase chain reaction. These regions were cloned, sequenced, and compared with GenBank sequences of the National Center for Biotechnology International. A statistical analysis was used to compare sequences from canine MCT and normal tissues. RESULTS: A significantly higher percentage of homozygous intron 11 deletion was found in canine MCT (49%) than in normal tissues (13%). This percentage was also higher in moderately and poorly differentiated MCT, compared with well-differentiated MCT Although no mutations were detected in any of the specimens, a polymorphism at amino acid position 606 of the canine c-kit sequence was found in all the studied sequences. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated a relationship between intron 11 deletion and MCT and the grade of MCT differentiation. We suggest that intron 11 deletion may be implicated in the pathogenesis of MCT and could be used as a marker for diagnosis and prognosis of canine MCT. 相似文献
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Pozo-Bayón MA G-Alegría E Polo MC Tenorio C Martín-Alvarez PJ Calvo de la Banda MT Ruiz-Larrea F Moreno-Arribas MV 《Journal of agricultural and food chemistry》2005,53(22):8729-8735
Red wine amino acids and volatile compounds were analyzed before and after malolactic fermentation carried out by four different starter cultures of the species Oenococcus oeni and Lactobacillus plantarum. The purpose of this study was to determine whether differences can be attributed to the lactic acid bacteria strain used in this important step of the wine-making process. The malolactic cultures selected for this study were indigenous wine lactic acid bacteria strains. The data were evaluated using different multivariate analysis techniques. Results showed different malolactic behaviors for O. oeni and L. plantarum and significant metabolic differences between both species. A degree of diversity was found within each lactic acid bacteria group, since wines presented specific characteristics depending on the lactic acid bacteria strain used. In all cases, malolactic fermentation seemed to modify the amino acid and volatile composition of the wine. 相似文献
55.
Serum haemolytic and agglutinating activity as indicators of fish immunocompetence: their suitability in stress and dietary studies 总被引:4,自引:0,他引:4
Gilthead sea bream, Sparus aurata, were subjected to different stressful situations and the haemolytic activity mediated by the alternative complement and the agglutinating serum activity were tested as indicators of immunocompetence. The results show that both parameters were significantly compromised after chronic or repeated acute stress as well as in groups fed with vitamin E or 3 highly unsaturated fatty acids (HUFA) deficient diets and in infected fish. These results suggest that both haemolytic and agglutinating activity are suitable indicators for immunocompetence as they are non-specific responses induced by non-specific stressors. In addition, a comparison is performed with other immune indicators subjected to the same stressors. 相似文献
56.
George Vardanis Liliana Sfichi‐Duke Lluis Tort Pascal Divanach Kiriakos Kotzabasis Michail Pavlidis 《Aquaculture Research》2011,42(3):341-350
The freshness of red porgy slaughtered in ice slurry and stored in melting ice was evaluated instrumentally, biochemically and sensorialy. Additionally, postmortem skin colour changes were monitored, in an attempt to demonstrate the use of chromaticity parameters as a reliable and convenient approach to quality assessment. Dielectric properties showed a statistically significant decrease (P<0.05) from 12±0 on day 0 to 7.85±0.31 on day 7; there was also a significant decrease in muscle polyamines with more than two amino groups (spermidine and spermine) and an increase in the di‐amine putrescine. The sensorial score was significantly decreased from 30±0 to 4.33±0.21 on day 7. Minimal lightness (L*) and hue (H°ab) at the dorsal skin area were observed on days 1 and 3 following harvesting. Finally, there was a marked decrease in the entire colour index (ECI – a combination of skin hue and chroma) of both the dorsal and the ventral area in day 3 onwards to day 7, as well as a statistically significant correlation between all the estimated freshness indices and ECI. Based on all these, we inferred that the total polyamines (or putrescine to spermidine and spermine ratio) and ECI could be reliable estimators of freshness, at least under the experimental conditions applied. 相似文献
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The main physical and chemical properties of a composted mixture of sewage sludge and wood chips, the nonamended soil, and soils amended with two rates of the compost, in the presence or absence of barley, were determined. Humic acids (HAs) isolated from these materials were characterized by various methods including elemental analysis and Fourier Transform infrared (FTIR), fluorescence, and electron spin resonance spectroscopies. With respect to the nonamended soil HA, the compost HA was characterized by a prevalent aliphatic character, low oxygenated functional group content, high contents of S, N-containing groups and polysaccharide components, low free radical concentration, high molecular heterogeneity, and low degrees of ring polycondensation, polymerization and humification. Compost application at the low rate appeared to induce only limited modifications in the structural and chemical properties of HAs from amended soils, whereas apparent modifications of HA properties occurred where a high amendment rate was used. The absence or presence of barley cultivation appeared not to exert any measurable effect on the composition and properties of compost-amended soil HAs. 相似文献
59.
Strong relations between population trends and spatial distribution have been suggested at the regional scale: declining species
should have more fragmented distributions because decline causes range retractions towards optimal habitats, whereas increasing
species should have more aggregated distributions, because colonization processes are constrained by distance. Most analyses
of the effects of land use changes on animal populations are diachronic studies of population dynamics or synchronic studies
of species habitat selection. Few studies take simultaneously into account temporal changes in habitat distribution and changes
in species spatial distribution. We applied the above rationale to the landscape scale and analysed how population declines,
increases or stability, as diagnosed in a long term study, correlate with population connectivity or fragmentation at that
scale. We used data on changes in faunal distribution and information on temporal changes in the vegetation in a Mediterranean
area that had been subjected to land abandonment. We found that species declining at the landscape scale had retracting fragmented
distributions and that expanding species had expanding continuous distributions. However, for the latter, we suggest that
the factors involved are related to landscape structure and not to dispersal mediated meta-population processes, which are
of little relevance at this local scale. We also show that even species that are numerically stable can show fragmentation
of their distribution and major spatial distribution shifts in response to land use changes, especially in species that have
low occurrence levels or that are associated with transitory habitats such as heterogeneous shrublands (e.g. Sylvia melanocephala). Studying the spatial structure of species distribution patterns at the landscape scale may provide information about population
declines and increases both at the regional and the landscape scale and can improve our understanding of short-term risks
of local extinction. 相似文献
60.
César Plaza Hero T. Gollany Guido Baldoni Alfredo Polo Claudio Ciavatta 《Journal of Soils and Sediments》2012,12(4):486-493