75 resultados para enrichment

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)


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This work is related to the so-called non-conventional finite element formulations. Essentially, a methodology for the enrichment of the initial approximation which is typical of the meshless methods and based on the clouds concept is introduced in the hybrid-Trefftz formulation for plane elasticity. The formulation presented allows for the approximation and direct enrichment of two independent fields: stresses in the domains and displacements on the boundaries of the elements. Defined by a set of elements and interior boundaries sharing a common node, the cloud notion is employed to select the enrichment support for the approximation fields. The numerical analysis performed reveals an excellent performance of the resulting formulation, characterized by the good approximation ability and a reduced computational effort. Copyright (C) 2009 John Wiley & Sons, Ltd.

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Modern lifestyle markedly changed eating habits worldwide, with an increasing demand for ready-to-eat foods, such as minimally processed fruits and leafy greens. Packaging and storage conditions of those products may favor the growth of psychrotrophic bacteria, including the pathogen Listeria monocytogenes. In this work, minimally processed leafy vegetables samples (n = 162) from retail market from Ribeirao Preto, Sao Paulo, Brazil, were tested for the presence or absence of Listeria spp. by the immunoassay Listeria Rapid Test, Oxoid. Two L. monocytogenes positive and six artificially contaminated samples of minimally processed leafy vegetables were evaluated by the Most Probable Number (MPN) with detection by classical culture method and also culture method combined with real-time PCR (RTi-PCR) for 16S rRNA genes of L monocytogenes. Positive MPN enrichment tubes were analyzed by RTi-PCR with primers specific for L. monocytogenes using the commercial preparation ABSOLUTET (TM) QPCR SYBR (R) Green Mix (ABgene, UK). Real-time PCR assay presented good exclusivity and inclusivity results and no statistical significant difference was found in comparison with the conventional culture method (p < 0.05). Moreover, RTi-PCR was fist and easy to perform, with MPN results obtained in ca. 48 h for RTi-PCR in comparison to 7 days for conventional method. (C) 2009 Elsevier Ltd. All rights reserved.

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Objective-To evaluate the presence of a dominance rank in a group of cats and the relation between agonistic behavior and the use of resources, including environmental enrichment, in these cats. Design-Observational analytic study. Animals-27 neutered cats in a shelter in Sao Paulo, Brazil. Procedures-The cats were video recorded for 4 consecutive days to obtain baseline data. Subsequently, a puzzle feeder was added as an enrichment device every other day over 8 days, for a total of 4 days with enrichment. Cats were also video recorded on these days. All pretreatment and posttreatment agonistic behaviors and interactions with the puzzle feeder were recorded by reviewing the videotapes. Results-143 agonistic encounters were recorded, of which 44 were related to resources and 99 were not. There were insufficient agonistic interactions to determine a dominance rank. Presence or absence of the puzzle feeder did not affect the rate of aggression. There was no significant effect of weight, sex, or coat color on the rate of aggression, and aggressive behavior did not correlate with time spent with the puzzle feeder. Twenty-three of the 27 cats interacted with the puzzle feeder. Conclusions and Clinical Relevance-In a stable group of communally housed cats, environmental enrichment did not cause increased aggression as a result of competition for the source of enrichment. Because environmental enrichment increases the opportunity to perform exploratory behaviors, it may improve the welfare of groups of cats maintained long-term in shelters, sanctuaries, or multicat households. (J Am Vet Med Assoc 2011239:796-802)

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Nonsyndromic cleft lip and palate (NSCL/P) is a complex disease resulting from failure of fusion of facial primordia, a complex developmental process that includes the epithelial-mesenchymal transition (EMT). Detection of differential gene transcription between NSCL/P patients and control individuals offers an interesting alternative for investigating pathways involved in disease manifestation. Here we compared the transcriptome of 6 dental pulp stem cell (DPSC) cultures from NSCL/P patients and 6 controls. Eighty-seven differentially expressed genes (DEGs) were identified. The most significant putative gene network comprised 13 out of 87 DEGs of which 8 encode extracellular proteins: ACAN, COL4A1, COL4A2, GDF15, IGF2, MMP1, MMP3 and PDGFa. Through clustering analyses we also observed that MMP3, ACAN, COL4A1 and COL4A2 exhibit co-regulated expression. Interestingly, it is known that MMP3 cleavages a wide range of extracellular proteins, including the collagens IV, V, IX, X, proteoglycans, fibronectin and laminin. It is also capable of activating other MMPs. Moreover, MMP3 had previously been associated with NSCL/P. The same general pattern was observed in a further sample, confirming involvement of synchronized gene expression patterns which differed between NSCL/P patients and controls. These results show the robustness of our methodology for the detection of differentially expressed genes using the RankProd method. In conclusion, DPSCs from NSCL/P patients exhibit gene expression signatures involving genes associated with mechanisms of extracellular matrix modeling and palate EMT processes which differ from those observed in controls. This comparative approach should lead to a more rapid identification of gene networks predisposing to this complex malformation syndrome than conventional gene mapping technologies.

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The oil obtained from Brazilian roasted coffee by supercritical CO2 extraction shows considerable aromatic properties, mainly composed by five aromatic compounds, 2-methylpyrazine; 2-furfurylalcohol, 2,5-dimethylpyrazine; γ-butyrolactone and 2-furfurylacetate. Sensory analyses were used to verify the influence of a mixture of these important classes of aromatic coffee compounds (pyrazines, furans and lactones) and of the roasted coffee aromatic oil on the coffee aroma and flavour of black instant freeze and spray-dried coffee beverages. In the acceptance evaluation of the aroma, the samples prepared with freeze-dried instant coffee without the mixture of volatile compounds (sample 4) were not significantly different from the freeze-dried instant coffee in which the aromatic coffee oil was added (sample 5) and from the sample prepared with freeze-dried coffee in which the mixture of the five volatile was added (sample 3), coincidentally from the same drying process. Therefore, sample (3) did not differ from samples prepared with spray dried instant coffee without (sample 1) and to which (sample 2) the mixture of volatile was added. Therefore, with respect to this attribute, the addition of this mixture did not interfere in this drink acceptance. Taking into consideration the flavor, samples prepared with freeze-dried instant coffee in which the aromatic coffee oil was added (5) and the samples with (3) and without (4) the mixture of the five volatile was added did not differ significantly, however sample (4) did not differ from samples (1) and (2). Regarding this attribute, the addition of the aromatic oil of roasted coffee or a mixture of volatile in samples of freeze-dried instant coffee had a better acceptance than those dried by spray dryer (1) and (2). Thus, the enrichment of drinks with the aromatic oil of roasted coffee, or even with the mixture of the five components did not influence the consumer acceptance with respect to the aroma, but exerts influence with respect to flavour.

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A enzima nitrato redutase (NR) catalisa a redução do nitrato a nitrito e controla a taxa de assimilação do nitrato. O ensaio in vitro da nitrato redutase foi otimizado para a linhagem selvagem (marrom, MA) e para a linhagem deficiente em ficoeritrina (verde-clara, VC) de Hypnea musciformis. As duas linhagens foram cultivadas em temperatura de 23 ± 2°C, fotoperíodo de 14 horas, irradiância de 60-90µmol fótons m-2s-1, e meio composto por água do mar esterilizada (30ups) enriquecida com a solução de von Stosch na concentração de 50% (VSES/2). As condições ótimas de ensaio para ambas as linhagens foram: 40µM de NADH; 10min de incubação do extrato bruto (EB) e 100µL de EB. A atividade ótima da NR ocorreu em 4 e 2mM de nitrato para a linhagem VC e MA, respectivamente. As linhagens VC e MA apresentaram, respectivamente, constante aparente de Michaelis-Menten (K M) para NADH de 0,2068 e 0,0837 µM, e K M para nitrato de 0,0492 e 0,0294mM. Os resultados indicam que a NR da linhagem MA tem maior afinidade pelo substrato do que a NR da linhagem VC de H. musciformis. Os experimentos para avaliar os efeitos da disponibilidade de nitrato (5 a 105µM) e nitrato e fosfato (0,5 a 25,5µM, com a relação N:P de 4:1) mostraram que a atividade da NR das linhagens VC e MA não aumentou com a adição de nitrato no meio, o que pode estar relacionado com o estado nutricional dessas algas. A atividade da NR foi maior nos tratamentos com adição de fosfato do que naqueles com adição de apenas nitrato, indicando que esse nutriente é importante para os processos metabólicos relacionados a atividade da NR.

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To develop a convenience healthy food snack the partially hydrogenated vegetable fat, used as the flavour fixative agent, was replaced by a non-fat-flavouring solution enriched with inulin and oligofructose. The effects of this replacement on chemical composition, in vitro rate of starch digestion and sensory acceptability were assessed. The new snack presented low-fat levels (0.1 per cent) and around a sevenfold increase in dietary fibre (15.3 per cent of dietary fibre, being 13.3 per cent of fructans) when compared with the traditional ones. The enrichment with fructans reduced the predicted Glycaemic Index by 25 per cent, thus indicating that this dietary fibre contributes effectively towards delaying the in vitro glycaemic response. Fructans-enriched snack presented overall acceptability score (6.6 ± 1.7) similar to the traditional one, flavoured with fatty fixative agent (7.4 ± 1.4). The healthy low-fat fibre-enriched snack produced presented the high sensory acceptability typical for this food product type

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The present study focuses on potential agents of chromoblastomycosis and other endemic diseases in the state of Parana, Southern Brazil. Using a highly selective protocol for chaetothyrialean black yeasts and relatives, environmental samples from the living area of symptomatic patients were analysed. Additional strains were isolated from creosote-treated wood and hydrocarbon-polluted environments, as such polluted sites have been supposed to enhance black yeast prevalence. Isolates showed morphologies compatible with the traditional etiological agents of chromoblastomycosis, e.g. Fonsecaea pedrosoi and Phialophora verrucosa, and of agents of subcutaneous or systemic infections like Cladophialophora bantiana and Exophiala jeanselmei. Some agents of mild disease were indeed encountered. However, molecular analysis proved that most environmental strains differed from known etiologic agents of pronounced disease syndromes: they belonged to the same order, but mostly were undescribed species. Agents of chromoblastomycosis and systemic disease thus far are prevalent on the human host. The hydrocarbon-polluted environments yielded yet another spectrum of chaetothyrialean fungi. These observations are of great relevance because they allow us to distinguish between categories of opportunists, indicating possible differences in pathogenicity and virulence.

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Premise of study: Microsatellite primers were developed for castor bean (Ricinus communis L.) to investigate genetic diversity and population structure, and to provide support to germplasm management. Methods and Results: Eleven microsatellite loci were isolated using an enrichment cloning protocol and used to characterize castor bean germplasm from the collection at the Instituto Agronomico de Campinas (IAC). In a survey of 76 castor bean accessions, the investigated loci displayed polymorphism ranging from two to five alleles. Conclusions: The information derived from microsatellite markers led to significant gains in conserved allelic richness and provides support to the implementation of several molecular breeding strategies for castor bean.

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Premise of the study: Microsatellite primers were developed for Aulonemia aristulata, an endangered species of economic interest, to further describe its genetic variability and population structure. We also tested cross-amplification in 18 other bamboo species. Methods and Results: Using an enrichment genomic library, 13 microsatellite loci were isolated and characterized in A. aristulata. Seven of these loci were polymorphic. Twelve markers were cross-amplified in at least ten of the tested bamboo species. Conclusions: These markers will be useful for studies on the genetic diversity and structure of A. aristulata, which are important for future conservation, management and breeding programs of this species.

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The immunogenic properties of cysteine proteases obtained from excretory/secretory products (ES) of Haemonchus contortus were investigated with a fraction purified with a recombinant H. contortus cystatin affinity column. The enrichment of H. contortus ES for cysteine protease was confirmed with substrate SDS-PAGE gels since the cystatin-binding fraction activity was three times higher than total ES, despite representing only 3% of total ES. This activity was inhibited by a specific cysteine protease inhibitor (E64) and by recombinant cystatin. The one-dimensional profile of the cystatin-binding fraction displayed a single band with a molecular mass of 43 kDa. Mass spectrometry showed this to be AC-5, a cathepsin B-like cysteine protease which had not been identified in ES products of H. contortus before. The cystatin binding fraction was tested as an immunogen in lambs which were vaccinated three times (week 0, 2.5 and 5), challenged with 10 000 L3 H. contortus (week 6) before necropsy and compared to unvaccinated challenge controls and another group given total ES (n = 10 per group). The group vaccinated with cystatin-binding proteins showed 36% and 32% mean worm burden and eggs per gram of faeces (EPG) reductions, respectively, compared to the controls but total ES was almost without effect. After challenge the cystatin-binding proteins induced significantly higher local and systemic ES specific IgA and IgG responses.

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We report the first quantitative and qualitative analysis of the poly (A)(+) transcriptome of two human mammary cell lines, differentially expressing (human epidermal growth factor receptor) an oncogene over-expressed in approximately 25% of human breast tumors. Full-length cDNA populations from the two cell lines were digested enzymatically, individually tagged according to a customized method for library construction, and simultaneously sequenced by the use of the Titanium 454-Roche-platform. Comprehensive bioinformatics analysis followed by experimental validation confirmed novel genes, splicing variants, single nucleotide polymorphisms, and gene fusions indicated by RNA-seq data from both samples. Moreover, comparative analysis showed enrichment in alternative events, especially in the exon usage category, in ERBB2 over-expressing cells, data indicating regulation of alternative splicing mediated by the oncogene. Alterations in expression levels of genes, such as LOX, ATP5L, GALNT3, and MME revealed by large-scale sequencing were confirmed between cell lines as well as in tumor specimens with different ERBB2 backgrounds. This approach was shown to be suitable for structural, quantitative, and qualitative assessment of complex transcriptomes and revealed new events mediated by ERBB2 overexpression, in addition to potential molecular targets for breast cancer that are driven by this oncogene.

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Background: Melanoma progression occurs through three major stages: radial growth phase (RGP), confined to the epidermis; vertical growth phase (VGP), when the tumor has invaded into the dermis; and metastasis. In this work, we used suppression subtractive hybridization (SSH) to investigate the molecular signature of melanoma progression, by comparing a group of metastatic cell lines with an RGP-like cell line showing characteristics of early neoplastic lesions including expression of the metastasis suppressor KISS1, lack of alpha v beta 3-integrin and low levels of RHOC. Methods: Two subtracted cDNA collections were obtained, one (RGP library) by subtracting the RGP cell line (WM1552C) cDNA from a cDNA pool from four metastatic cell lines (WM9, WM852, 1205Lu and WM1617), and the other (Met library) by the reverse subtraction. Clones were sequenced and annotated, and expression validation was done by Northern blot and RT-PCR. Gene Ontology annotation and searches in large-scale melanoma expression studies were done for the genes identified. Results: We identified 367 clones from the RGP library and 386 from the Met library, of which 351 and 368, respectively, match human mRNA sequences, representing 288 and 217 annotated genes. We confirmed the differential expression of all genes selected for validation. In the Met library, we found an enrichment of genes in the growth factors/receptor, adhesion and motility categories whereas in the RGP library, enriched categories were nucleotide biosynthesis, DNA packing/repair, and macromolecular/vesicular trafficking. Interestingly, 19% of the genes from the RGP library map to chromosome 1 against 4% of the ones from Met library. Conclusion: This study identifies two populations of genes differentially expressed between melanoma cell lines from two tumor stages and suggests that these sets of genes represent profiles of less aggressive versus metastatic melanomas. A search for expression profiles of melanoma in available expression study databases allowed us to point to a great potential of involvement in tumor progression for several of the genes identified here. A few sequences obtained here may also contribute to extend annotated mRNAs or to the identification of novel transcripts.

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Background: Without intensive selection, the majority of bovine oocytes submitted to in vitro embryo production (IVP) fail to develop to the blastocyst stage. This is attributed partly to their maturation status and competences. Using the Affymetrix GeneChip Bovine Genome Array, global mRNA expression analysis of immature (GV) and in vitro matured (IVM) bovine oocytes was carried out to characterize the transcriptome of bovine oocytes and then use a variety of approaches to determine whether the observed transcriptional changes during IVM was real or an artifact of the techniques used during analysis. Results: 8489 transcripts were detected across the two oocyte groups, of which similar to 25.0% (2117 transcripts) were differentially expressed (p < 0.001); corresponding to 589 over-expressed and 1528 under-expressed transcripts in the IVM oocytes compared to their immature counterparts. Over expression of transcripts by IVM oocytes is particularly interesting, therefore, a variety of approaches were employed to determine whether the observed transcriptional changes during IVM were real or an artifact of the techniques used during analysis, including the analysis of transcript abundance in oocytes in vitro matured in the presence of a-amanitin. Subsets of the differentially expressed genes were also validated by quantitative real-time PCR (qPCR) and the gene expression data was classified according to gene ontology and pathway enrichment. Numerous cell cycle linked (CDC2, CDK5, CDK8, HSPA2, MAPK14, TXNL4B), molecular transport (STX5, STX17, SEC22A, SEC22B), and differentiation (NACA) related genes were found to be among the several over-expressed transcripts in GV oocytes compared to the matured counterparts, while ANXA1, PLAU, STC1and LUM were among the over-expressed genes after oocyte maturation. Conclusion: Using sequential experiments, we have shown and confirmed transcriptional changes during oocyte maturation. This dataset provides a unique reference resource for studies concerned with the molecular mechanisms controlling oocyte meiotic maturation in cattle, addresses the existing conflicting issue of transcription during meiotic maturation and contributes to the global goal of improving assisted reproductive technology.

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Context. Our understanding of the chemical evolution (CE) of the Galactic bulge requires the determination of abundances in large samples of giant stars and planetary nebulae (PNe). Studies based on high resolution spectroscopy of giant stars in several fields of the Galactic bulge obtained with very large telescopes have allowed important progress. Aims. We discuss PNe abundances in the Galactic bulge and compare these results with those presented in the literature for giant stars. Methods. We present the largest, high-quality data-set available for PNe in the direction of the Galactic bulge (inner-disk/bulge). For comparison purposes, we also consider a sample of PNe in the Large Magellanic Cloud (LMC). We derive the element abundances in a consistent way for all the PNe studied. By comparing the abundances for the bulge, inner-disk, and LMC, we identify elements that have not been modified during the evolution of the PN progenitor and can be used to trace the bulge chemical enrichment history. We then compare the PN abundances with abundances of bulge field giant. Results. At the metallicity of the bulge, we find that the abundances of O and Ne are close to the values for the interstellar medium at the time of the PN progenitor formation, and hence these elements can be used as tracers of the bulge CE, in the same way as S and Ar, which are not expected to be affected by nucleosynthetic processes during the evolution of the PN progenitors. The PN oxygen abundance distribution is shifted to lower values by 0.3 dex with respect to the distribution given by giants. A similar shift appears to occur for Ne and S. We discuss possible reasons for this PNe-giant discrepancy and conclude that this is probably due to systematic errors in the abundance derivations in either giants or PNe (or both). We issue an important warning concerning the use of absolute abundances in CE studies.