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Transcriptomic profile reveals molecular events associated to focal adhesion and invasion in canine mammary gland tumour cell lines 下载免费PDF全文
Y. G. Cordeiro P. L. P. Xavier A. L. Rochetti P. A. Alexandre C. M. C. Mori R. F. Strefezzi H. Fukumasu 《Veterinary and comparative oncology》2018,16(1):E89-E98
The prevalence of cancer in animals has increased significantly over the years. Mammary tumours are the most common neoplasia in dogs, in which around 50% are presented in the malignant form. Hence, the development and characterization of in vitro models for the study of canine tumours are important for the improvement of cancer diagnosis and treatment. Thus, the aim of this study was to characterize cell lines derived from canine mammary gland neoplasias which could be further used for basic and applied oncology research. Samples of canine mammary carcinomas were taken for cell culture and 2 cell lines were established and characterized in terms of cell morphology, tumourigenicity and global gene expression. Both cell lines presented spindle‐shape morphology and shown common malignant features as in vitro invasion potential and expression of epithelial and mesenchymal proteins. Also, we found gene expression patterns between the 2 cell cultures in comparison to the normal mammary gland tissue. Cells from M25 culture showed a higher invasion and in vivo tumourigenic potential, associated to the overexpression of genes involved in focal adhesion and extracellular matrix communication, such as FN1, ITGA8 and THBS2. The phenotypic characterization of these cells along with their global gene expression profile potentially determine new therapeutic targets for mammary tumours. 相似文献
54.
Rita Bastos António T. Monteiro Diogo Carvalho Carla Gomes Paulo Travassos João P. Honrado Mário Santos João Alexandre Cabral 《Landscape Ecology》2016,31(4):701-710
Context
Land-use/land-cover (LU/LC) dynamics is one of the main drivers of global environmental change. In the last years, aerial and satellite imagery have been increasingly used to monitor the spatial extent of changes in LU/LC, deriving relevant biophysical parameters (i.e. primary productivity, climate and habitat structure) that have clear implications in determining spatial and temporal patterns of biodiversity, landscape composition and ecosystem services.Objectives
An innovative hierarchical modelling framework was developed in order to address the influence of nested attributes of LU/LC on community-based ecological indicators.Methods
Founded in the principles of the spatially explicit stochastic dynamic methodology (StDM), the proposed methodological advances are supported by the added value of integrating bottom-up interactions between multi-scaled drivers.Results
The dynamics of biophysical multi-attributes of fine-scale subsystem properties are incorporated to inform dynamic patterns at upper hierarchical levels. Since the most relevant trends associated with LU/LC changes are explicitly modelled within the StDM framework, the ecological indicators’ response can be predicted under different social-economic scenarios and site-specific management actions. A demonstrative application is described to illustrate the framework methodological steps, supporting the theoretic principles previously presented.Conclusions
We outline the proposed multi-model framework as a promising tool to integrate relevant biophysical information to support ecosystem management and decision-making.55.
Comparison of serological assays for the diagnosis of canine visceral leishmaniasis in animals presenting different clinical manifestations 总被引:1,自引:0,他引:1
Ferreira Ede C de Lana M Carneiro M Reis AB Paes DV da Silva ES Schallig H Gontijo CM 《Veterinary parasitology》2007,146(3-4):235-241
Three serological methods, indirect fluorescent immunoassay (IFI), enzyme-linked immunosorbent assay (ELISA) and direct agglutination test (DAT) that are commonly employed in the diagnosis of canine visceral leishmaniasis (CVL), have been assessed. A total of 234 domestic dogs, drawn from an area in the municipality of Belo Horizonte, Minas Gerais, Brazil, endemic for visceral leishmaniasis, were submitted to clinical and parasitological examinations and serological assay. Sera collected from confirmed non-infected dogs (n=20), and from dogs with other parasitic diseases including Trypanosoma cruzi (n=7), Leishmania braziliensis (n=5), Toxoplasma gondii (n=5) and Ehrlichia canis (n=3), were also included in the study. IFI presented a lower sensitivity (72%) than ELISA (95%), although the specificities of these assays were low (52 and 64%, respectively) and both exhibited cross-reactivity with sera from dogs infected with T. cruzi, L. braziliensis and E. canis. In contrast, DAT exhibited a high sensitivity (93%) and a high specificity (95%) and cross-reacted with only one serum sample derived from an E. canis-infected dog. The reproducibilities of the ELISA and DAT assays were excellent, whilst that of IFI was considered to be acceptable. The results produced by ELISA and DAT were in complete agreement, those between ELISA and IFI were at an acceptable level of agreement, whilst the concurrence between the IFI and DAT results were either acceptable or poor depending on the clinical conditions of the group of dogs examined. Since there is no readily accessible method for the diagnosis of CVL that offers 100% specificity and sensitivity, the choice of technique employed must depend on the aim of the investigation. 相似文献
56.
Garcia JL Navarro IT Biazzono L Freire RL da Silva Guimarães Junior J Cryssafidis AL Bugni FM da Cunha IA Hamada FN Dias RC 《Veterinary parasitology》2007,145(3-4):197-206
This study evaluated a vaccine made from crude rhoptry proteins of Toxoplasma gondii with Quil-A, which was administered to cats by the intranasal route. Eleven short-hair domestic cats were divided into four groups: G1 (n=3) received three doses (200 microg/dose) of the rhoptry vaccine with Quil-A (20 microg); G2 (n=3) received PBS with Quil-A (20 microg); G3 (n=3) and G4 (n=2) received only PBS. Treatments were administered at days 0, 21, and 42 by the intranasal route. Challenge was done to G1, G2, and G3 animals with 600 cysts of the VEG strain on day 51 (challenge day); G4 animals were unchallenged. The anti-T. gondii IgG and IgA antibody levels from sera were measured by indirect enzyme-linked immunosorbent assay (ELISA). At challenge, two animals from G1 revealed antibody levels for both IgG and IgA; oocysts were not detected in feces of these two cats. There were no differences in hematological values between groups throughout the experiment (p>0.10). Preventable fractions were 67% in G1 and 0% in G2 and G3. Comparatively, G1 animals shed 89.3% and 90.8% less oocysts than G3 and G4, respectively. Two out of three cats were protected against T. gondii oocyst shedding when the rhoptry vaccine was administered by the intranasal route. This is the first study using crude rhoptry proteins as vaccine by the intranasal route in cats to evaluate protection against oocysts shedding. 相似文献
57.
This study focused on the capability of two silty soils (tills) having low clay contents and CEC to retain and release two heavy metals, Pb and Cu. Samples of two non contaminated till deposits from the Eastern Townships region of Quebec, Canada, were artificially contaminated with concentrated solutions of these heavy metals. The latter were later extracted from the various geochemical phases of the soils by using the sequential extraction procedure. The results show that silty soils may have a relatively high heavy metal retention capacity due to the presence of carbonate and that this retention capacity can be comparable in magnitude to the retention capacity of certain clayey soils. This is particularly positive in the context of municipal waste disposal (landfills) in Quebec, where some old sanitary landfill sites are underlain by till deposits. A high buffering capacity is not as desirable in the case a deposit needs to undergo remediation. 相似文献
58.
Aurielle S. Medeiros Mércia V. F. dos Santos Márcio V. da Cunha Alexandre C. L. de Mello Djalma E. Simões Neto Osniel F. de Oliveira James P. Muir Jose C. B. Dubeux Jr André E. dos Santos 《Grass and Forage Science》2023,78(1):161-172
The use of legumes is an important strategy for animal feeding, especially during the dry season. The aim was to evaluate the effect of planting densities (40,000; 15,625 and 10,000 plants ha−1) and harvest heights (20 and 40 cm) on the morphology, accumulation and survival of Desmanthus (Desmanthus pernambucanus [L.] Thellung), cultivated in subhumid tropical region, as well as to estimate the repeatability of the evaluated characteristics and the optimal number of measurements. The treatments were randomized in blocks, with subdivided plots and four replicates. Planting densities were evaluated in the plots and the harvest heights in the subplots. Eight harvests were carried out with an interval of 84 days. Morphological and productive characteristics and survival were evaluated. Cultivation under density of 40,000 plants ha−1 produced taller plants, with higher leaf area index (LAI = 0.98), light interception (LI = 49%), individual accumulations (18.8 g DM plant−1) and by area (576.5 kg DM ha−1 harvest−1), although resulting in reduced plant stand (66%). Harvest heights do not affect accumulation and survival. It is possible to reduce the number of measurements for stem diameter, number of leaflets per leaf (R2 = 95%), plant height, canopy diameter, LAI, LI, leaf length and width, number of leaves per branch, branch diameter and LBR (R2 = 90%), optimizing resources for future research. Desmanthus has potential for use in protein banks, being harvested in the rainy season, conserved and supplied in addition to animals, but plant growth is minimal during the dry season under rainfed conditions. 相似文献
59.
Robson Elpídio Pereira Ribeiro Alexandre Carneiro Leão de Mello Márcio Vieira da Cunha Suellen Brandão de Miranda Costa Janerson José Coelho Rayanne Thalita de Almeida de Souza Mércia Virginia Ferreira dos Santos 《Grass and Forage Science》2023,78(1):194-203
This study hypothesised that different elephant grass genotypes respond differently in terms of their morphological development to irrigation. The objective of this study was to evaluate how water availability could affect the morphological development of different genotypes of elephant grass. The treatments consisted of four genotypes of elephant grass [Cenchrus purpureus (Schumach.) Morrone], managed under irrigation or not, during a two-year field trial. The experiment was arranged in a randomised block design in a split-plot, with four replicates per treatment (n = 4). Between the genotypes, two of them were classified as tall-sized (IRI 381 and Elephant B), and two as dwarfs (Taiwan A-146 2.37 and Mott). A three-way interaction between season, irrigation, and genotype affected the variables plant height, stem diameter, number of dead tillers, light interception (LI), and leaf area index (LAI) (p < .05). The morphological development of all genotypes was negatively impacted by the dry season. All genotypes grew taller during the rainy season (p < .05) and had a greater light interception (62%–80%) compared to the dry period (28%–59%). The genotype Mott, showed comparable LI and LAI to the tall-sized genotypes, whilst Taiwan A-146 2.37 was characterized by the lowest values, despite being the genotype with the greatest tiller density (60 tillers m−2) (p < .05). The use of irrigation mitigated the negative effects of the dry season on the plants, however, the type and size (tall vs. dwarf) of the elephant grass genotypes defined the extent of the responses to the use of the irrigation during the dry period. 相似文献
60.
Single nucleotide polymorphisms in the growth hormone gene of Oreochromis niloticus and their association with growth performance 下载免费PDF全文
Suhaila Karim Khalil Jaser Marco Aurélio Dessimoni Dias Aline de Assis Lago Rafael Vilhena Reis Neto Alexandre Wagner Silva Hilsdorf 《Aquaculture Research》2017,48(12):5835-5845
Polymorphisms in the growth hormone (GH) gene that is associated with the growth rate of farmed fish have been the target of many breeding programmes. The present study aimed to identify single nucleotide polymorphisms (SNPs) in GH gene regions to evaluate the association of SNP variations with the growth rate of two Nile tilapia: Oreochromis niloticus (Linnaeus, 1758) strains. The targeted regions were amplified, sequenced, aligned and screened for the presence of SNPs; thereafter, performance tests were used to check for the association between SNPs and weight. Allele and genotype frequencies were estimated for each SNP and genotype. Genotype blocks or sets of SNP genotypes and frequencies were also estimated. Association between SNPs and growth rate was statistically evaluated using a univariate linear mixed model that included both fixed and random effects. A total of 10 SNPs were identified, nine in the proximal promoter and one located in the 5′ UTR, forming 10 genotype blocks. In all weight recordings, five genotype blocks were significantly associated with the highest weights. Single nucleotide polymorphisms 6‐10 were also found to be significantly associated with growth (p‐value < .05). Genotypes with higher additive genetic values for weight were identified in the Chitralada strain, suggesting a possible impact of these additive effects of the GH SNP genotype on the growth rate of Nile tilapia. These findings may be used as part of marker‐assisted selection in tilapia breeding programmes. 相似文献