65 research outputs found

    An integrative assessment to determine the genotoxic hazard of estuarine sediments: combining cell and whole-organism responses

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    The application of the Comet assay in environmental monitoring remains challenging in face of the complexity of environmental stressors, e.g., when dealing with estuarine sediments, that hampers the drawing of cause-effect relationships. Although the in vitro Comet assay may circumvent confounding factors, its application in environmental risk assessment (ERA) still needs validation. As such, the present work aims at integrating genotoxicity and oxidative DNA damage induced by sediment-bound toxicants in HepG2 cells with oxidative stress-related effects observed in three species collected from an impacted estuary. Distinct patterns were observed in cells exposed to crude mixtures of sediment contaminants from the urban/industrial area comparatively to the ones from the rural/riverine area of the estuary, with respect to oxidative DNA damage and oxidative DNA damage. The extracts obtained with the most polar solvent and the crude extracts caused the most significant oxidative DNA damage in HepG2 cells, as measured by the formamidopyrimidine-DNA glycosylase (FPG)-modified Comet assay. This observation suggests that metals and unknown toxicants more hydrophilic than polycyclic aromatic hydrocarbons may be important causative agents, especially in samples from the rural part of the estuary, where oxidative DNA damage was the most significant. Clams, sole, and cuttlefish responded differentially to environmental agents triggering oxidative stress, albeit yielding results accordant with the oxidative DNA damage observed in HepG2 cells. Overall, the integration of in vivo biomarker responses and Comet assay data in HepG2 cells yielded a comparable pattern, indicating that the in vitro FPG-modified Comet assay may be an effective and complementary line-of-evidence in ERA even in particularly challenging, natural, scenarios such as estuarine environments

    Identidades de professores música: narrativas de acordeonistas

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    No artigo analisou-se características identitárias na formação de cinco professores de acordeom de cinco distintas cidades do Rio Grande do Sul. Para isso, apoiou-se em teorias que abordam a formação de professores de música e na teoria da mutação identitária apresentada por Dubar (2009). O estudo se caracteriza como qualitativo e as narrativas foram coletadas por meio de entrevistas semi-estruturadas fazendo uso da História Oral. Na discussão teórica é apresentada uma interpretação das narrativas destacando traços identitários estudados por Dubar(2009). Dentro das instituições que o autor analisa como estando em crise, destacam-se nos dados a questão de família, essa mais como legado de tradição do que crise, questões de gênero, trabalho e religião. Pela análise da crise das identidades pretende-se contribuir para o debate sobre sociologia da Educação Musical focalizado na formação de professores de instrumentos, estando aqui a principal relevância deste trabalho

    Androgen responsive intronic non-coding RNAs

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    BACKGROUND: Transcription of large numbers of non-coding RNAs originating from intronic regions of human genes has been recently reported, but mechanisms governing their biosynthesis and biological functions are largely unknown. In this work, we evaluated the existence of a common mechanism of transcription regulation shared by protein-coding mRNAs and intronic RNAs by measuring the effect of androgen on the transcriptional profile of a prostate cancer cell line. RESULTS: Using a custom-built cDNA microarray enriched in intronic transcribed sequences, we found 39 intronic non-coding RNAs for which levels were significantly regulated by androgen exposure. Orientation-specific reverse transcription-PCR indicated that 10 of the 13 were transcribed in the antisense direction. These transcripts are long (0.5–5 kb), unspliced and apparently do not code for proteins. Interestingly, we found that the relative levels of androgen-regulated intronic transcripts could be correlated with the levels of the corresponding protein-coding gene (asGAS6 and asDNAJC3) or with the alternative usage of exons (asKDELR2 and asITGA6) in the corresponding protein-coding transcripts. Binding of the androgen receptor to a putative regulatory region upstream from asMYO5A, an androgen-regulated antisense intronic transcript, was confirmed by chromatin immunoprecipitation. CONCLUSION: Altogether, these results indicate that at least a fraction of naturally transcribed intronic non-coding RNAs may be regulated by common physiological signals such as hormones, and further corroborate the notion that the intronic complement of the transcriptome play functional roles in the human gene-expression program

    Differences in breast cancer risk after benign breast disease by type of screening diagnosis

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    Neoplàsies de mama; Detecció precoç del càncer; Factors de riscNeoplasias de mama; Detección precoz del cáncer; Factores de riesgoBreast neoplasms; Early cancer detection; Risk factorsIntroduction: We aimed to assess differences in breast cancer risk across benign breast disease diagnosed at prevalent or incident screens. Materials and methods: We conducted a retrospective cohort study with data from 629,087 women participating in a long-standing population-based breast cancer screening program in Spain. Each benign breast disease was classified as non-proliferative, proliferative without atypia, or roliferative with atypia, and whether it was diagnosed in a prevalent or incident screen. We used partly conditional Cox hazard regression to estimate the adjusted hazard ratios of the risk of breast cancer. Results: Compared with women without benign breast disease, the risk of breast cancer was significantly higher (p-value ¼ 0.005) in women with benign breast disease diagnosed in an incident screen (aHR, 2.67; 95%CI: 2.24e3.19) than in those with benign breast disease diagnosed in a prevalent screen (aHR, 1.87; 95%CI: 1.57e2.24). The highest risk was found in women with a proliferative benign breast disease with atypia (aHR, 4.35; 95%CI: 2.09e9.08, and 3.35; 95%CI: 1.51e7.40 for those diagnosed at incident and prevalent screens, respectively), while the lowest was found in women with non-proliferative benign breast disease (aHR, 2.39; 95%CI: 1.95e2.93, and 1.63; 95%CI: 1.32e2.02 for those diagnosed at incident and prevalent screens, respectively). Conclusion: Our study showed that the risk of breast cancer conferred by a benign breast disease differed according to type of screen (prevalent or incident). To our knowledge, this is the first study to analyse the impact of the screening type on benign breast disease prognosisThis study was supported by grants from Instituto de Salud Carlos III FEDER (grant numbers: PI15/00098 and PI17/00047), and by the Research Network on Health Services in Chronic Diseases (RD12/0001/0015

    Cytocompatibility and biocompatibility of nanostructured carbonated hydroxyapatite spheres for bone repair

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    Objective The aim of this study was to investigate the in vitro and in vivo biological responses to nanostructured carbonated hydroxyapatite/calcium alginate (CHA) microspheres used for alveolar bone repair, compared to sintered hydroxyapatite (HA). Material and Methods The maxillary central incisors of 45 Wistar rats were extracted, and the dental sockets were filled with HA, CHA, and blood clot (control group) (n=5/period/group). After 7, 21 and 42 days, the samples of bone with the biomaterials were obtained for histological and histomorphometric analysis, and the plasma levels of RANKL and OPG were determined via immunoassay. Statistical analysis was performed by Two-Way ANOVA with post-hoc Tukey test at 95% level of significance. Results The CHA and HA microspheres were cytocompatible with both human and murine cells on an in vitro assay. Histological analysis showed the time-dependent increase of newly formed bone in control group characterized by an intense osteoblast activity. In HA and CHA groups, the presence of a slight granulation reaction around the spheres was observed after seven days, which was reduced by the 42nd day. A considerable amount of newly formed bone was observed surrounding the CHA spheres and the biomaterials particles at 42-day time point compared with HA. Histomorphometric analysis showed a significant increase of newly formed bone in CHA group compared with HA after 21 and 42 days from surgery, moreover, CHA showed almost 2-fold greater biosorption than HA at 42 days (two-way ANOVA,

    Genome mapping and expression analyses of human intronic noncoding RNAs reveal tissue-specific patterns and enrichment in genes related to regulation of transcription

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    Abstract\ud \ud \ud \ud Background\ud \ud RNAs transcribed from intronic regions of genes are involved in a number of processes related to post-transcriptional control of gene expression. However, the complement of human genes in which introns are transcribed, and the number of intronic transcriptional units and their tissue expression patterns are not known.\ud \ud \ud \ud Results\ud \ud A survey of mRNA and EST public databases revealed more than 55,000 totally intronic noncoding (TIN) RNAs transcribed from the introns of 74% of all unique RefSeq genes. Guided by this information, we designed an oligoarray platform containing sense and antisense probes for each of 7,135 randomly selected TIN transcripts plus the corresponding protein-coding genes. We identified exonic and intronic tissue-specific expression signatures for human liver, prostate and kidney. The most highly expressed antisense TIN RNAs were transcribed from introns of protein-coding genes significantly enriched (p = 0.002 to 0.022) in the 'Regulation of transcription' Gene Ontology category. RNA polymerase II inhibition resulted in increased expression of a fraction of intronic RNAs in cell cultures, suggesting that other RNA polymerases may be involved in their biosynthesis. Members of a subset of intronic and protein-coding signatures transcribed from the same genomic loci have correlated expression patterns, suggesting that intronic RNAs regulate the abundance or the pattern of exon usage in protein-coding messages.\ud \ud \ud \ud Conclusion\ud \ud We have identified diverse intronic RNA expression patterns, pointing to distinct regulatory roles. This gene-oriented approach, using a combined intron-exon oligoarray, should permit further comparative analysis of intronic transcription under various physiological and pathological conditions, thus advancing current knowledge about the biological functions of these noncoding RNAs.The authors thank Camila Egidio for help with testing the Agilent microarray protocol. The authors also thank Dr Marcia Kubrusly (Hospital das Clínicas, Universidade de São Paulo) and Dr Marcello Barcinski (Instituto Nacional de Câncer, Rio de Janeiro) for providing the tissue samples. This work was supported by a grant from Fundação de Amparo a Pesquisa do Estado de São Paulo, FAPESP to SVA, EMR and AMDS and by fellowships from FAPESP and Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq, Brasil.The authors thank Camila Egidio for help with testing the Agilent microarray protocol. The authors also thank Dr Marcia Kubrusly (Hospital das Clínicas, Universidade de São Paulo) and Dr Marcello Barcinski (Instituto Nacional de Câncer, Rio de Janeiro) for providing the tissue samples. This work was supported by a grant from Fundação de Amparo a Pesquisa do Estado de São Paulo, FAPESP to SVA, EMR and AMDS and by fellowships from FAPESP and Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq, Brasil

    HERA - Environmental Risk Assessment of a contaminated estuarine environment: a case study

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    Sado River estuary is located in the west coast of Portugal. Previous environmental studies identified industrial contamination, non-point anthropogenic sources and contamination coming from the river, all promoting accumulation of polluted sediments with known impacts on the ecological system. Surrounding human populations have intense economic fishery activities. Together with agriculture, estuary fishing products are available to local residents. Food usage previously characterized through ethnographic studies suggests exposure to estuarine products, farming products, and water in daily activities, as potential routes of contamination. It is well established that long term exposure to heavy metals are associated with renal and neurological diseases, most heavy metals are classified as carcinogenic and teratogenic.Instituição Financiadora: FCT; Instituições participantes: IMAR -Instituto do Mar (coord.)e PRÓ-INSA, Associação para a Promoção da Investigação em Saúde, Instituto Nacional de Saúde Doutor Ricardo Jorg
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