1,987 research outputs found
Phenolic acids and derivatives:Â studies on the relationship among structure, radical scavenging activity, and physicochemical parameters
The antiradical activity of caffeic acid (1), dihydrocaffeic acid (5), and their corresponding n-alkyl esters was evaluated by using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) method. Dihydrocaffeic acid (5) was the most potent compound, having an antiradical effect higher than that of (+/-)-alpha-tocopherol, whereas caffeic acid (1) was less efficient. Esterification of the carboxyl group of dihydrocaffeic acid (5) had a dramatic effect on its antiradical potency, but similar effects were not observed for caffeic acid (1) derivatives. The n-alkyl esters of both phenolic series had similar potencies, and their antiradical activities were independent of the alkyl chain length. Dose-dependent scavenger effects were found in both series. Acid-base properties of the compounds, evaluated by using potentiometry and spectrophotometry, showed that the catechol moiety had pK(a2) and pK(a3) values of 9. 24-9.02 and 11.38-10.99 in the dihydrocaffeic series and 8.48-8.24 and 11.38-11.07 in the caffeic series, respectively. Antiradical activity and pK(a) values of the compounds were not related.info:eu-repo/semantics/publishedVersio
Analysis of EGFR Overexpression, EGFR gene amplification and the EGFRvIII Mutation in portuguese high-grade gliomas
Background: Patients with malignant gliomas do not respond to any current therapy. Epidermal growth factor receptor (EGFR) controls several oncogenic processes, being
frequently up-regulated in gliomas due to overexpression, gene amplification and gene mutation. EGFR inhibitors are being tried in gliomas, yet the molecular determinants of therapeutic response are unclear. Materials and Methods: EGFR overexpression, EGFRvIII mutation and EGFR amplification were determined by immunohistochemistry and chromogenic in situ hybridization (CISH) in 27 primary glioblastomas (GBM), 24 anaplastic oligodendrogliomas (AO) and four
anaplastic oligoastrocytomas (AOA). Results: EGFR overexpression was associated with EGFR amplification, being found in 48% and 53% GBM, 33% and 40% AO and 75%
and 67% AOA, respectively. EGFRvIII was found in 22% GBM, 8% AO and was absent in AOA. No association was observed between EGFR alterations and patient survival.
Conclusion: We characterized, for the first time, EGFR molecular alterations in Portuguese patients with malignant
glioma and identified a subpopulation of patients presenting putative biomarkers for EGFR-based therapies
Manual de Edição das Gazetas Manuscritas da Biblioteca Pública de Évora
A edição de um maiores testemunhos narrativos do reinado de D. João V impõe a observância de procedimentos de transcrição, anotação e indexação relativamente complexos. Tendo por meta consolidar o percurso dos últimos anos e considerando a necessidade de ajustar o trabalho em equipa, procura-se aqui proceder a um exercÃcio de pormenorização de critérios, com base na estrutura dos volumes já publicados e num novo contacto com as normas disponÃveis sobre a recuperação de informações bibliográficas e documentais.Editing one of the largest narrative reports from the reign of D. João V demands the practice of fairly complex transcription, annotation and indexing procedures. To firm the track that has been opened in the last few years, and due to the need of making adjustments on team working rules, this is an essay of establishing a list of detailed criteria, built upon the structure observed on the volumes already printed, and bearing in mind international normative principles of accessing documentary and bibliograÂphical information
In Vitro Hepatotoxic and Neurotoxic Effects of Titanium and Cerium Dioxide Nanoparticles, Arsenic and Mercury Co-Exposure
This article belongs to the Special Issue Toxicity of Nanomaterials and Legacy Contaminants: Risks to the Environment and Human Health.Considering the increasing emergence of new contaminants, such as nanomaterials, mixing with legacy contaminants, including metal(loid)s, it becomes imperative to understand the toxic profile resulting from these interactions. This work aimed at assessing and comparing the individual and combined hepatotoxic and neurotoxic potential of titanium dioxide nanoparticles (TiO2NPs 0.75-75 mg/L), cerium oxide nanoparticles (CeO2NPs 0.075-10 μg/L), arsenic (As 0.01-2.5 mg/L), and mercury (Hg 0.5-100 mg/L) on human hepatoma (HepG2) and neuroblastoma (SH-SY5Y) cells. Viability was assessed through WST-1 (24 h) and clonogenic (7 days) assays and it was affected in a dose-, time- and cell-dependent manner. Higher concentrations caused greater toxicity, while prolonged exposure caused inhibition of cell proliferation, even at low concentrations, for both cell lines. Cell cycle progression, explored by flow cytometry 24 h post-exposure, revealed that TiO2NPs, As and Hg but not CeO2NPs, changed the profiles of SH-SY5Y and HepG2 cells in a dose-dependent manner, and that the cell cycle was, overall, more affected by exposure to mixtures. Exposure to binary mixtures revealed either potentiation or antagonistic effects depending on the composition, cell type and time of exposure. These findings prove that joint toxicity of contaminants cannot be disregarded and must be further explored.This research was funded by FEDER—Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020—Operacional Programme for Competitiveness and Internationalisation (POCI), and by Portuguese funds through FCT—Fundação para a Ciência e a Tecnologia in the framework of the project POCI-01-0145-FEDER-029651. This work was also financed by national funds through FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of projects UIDB/04750/2020 and LA/P/0064/2020. This work was also developed within the scope of the project CICECO- Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC). A.T. Reis thanks the financial support of FCT through individual Grant SFRH/BPD/122112/2016. C.B. Lopes and A.C. Estrada acknowledge their research position funded by national funds (OE), through FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19.info:eu-repo/semantics/publishedVersio
Novel and classic myoepithelial/stem cell markers in metaplastic carcinomas of the breast
Metaplastic carcinomas of the breast (MCBs) are unusual neoplasms
characterized by an admixture of glandular epithelial
components, which frequently exhibit features of squamous
differentiation, and mesenchymal malignant components. Regardless
of the presence of myoepithelial features in MCB, no
consensus concerning their putative histogenesis has yet been
achieved. Recently, novel putative myoepithelial markers have
been developed, including p63, maspin, and P-cadherin. We
assessed the expression of these myoepithelial markers in
MCBs and compared their expression with classic myoepithelial
markers. Immunohistochemistry using the streptavidin–
biotin–peroxidase complex technique with antibodies raised
against p63, maspin, P-cadherin, actin (clones CGA7, 1A4 and
HHF35), cytokeratin 14 (Ck14), and vimentin was performed
on 16 MCBs (7 matrix-producing MCBs, 6 adenosquamous
MCBs, and 3 MCBs with heterologous elements). In healthy
breast lobules and ducts adjacent to the tumors, myoepithelial
cells showed distinctive and consistent immunoreactivity for
p63, maspin, P-cadherin, actin, S-100 protein, and Ck14. Matrix-
producing MCBs were positive for maspin in all cases, for
p63 in 4 of 7 cases, and for P-cadherin in 4 of 7 cases. Adenosquamous
MCB showed immunoreactivity for p63, maspin,
and P-cadherin in 5 of 6 cases. All novel myoepithelial markers
and Ck14 decorated squamous cell islands. MCBs with heterologous
elements were positive for p63 in 1 case, for maspin in
all 3 cases, and for P-cadherin in 2 cases. All cases showed at
least one of the novel myoepithelial markers. Eleven of 16
cases were positive for actin. Eleven of 14 cases reacted with
Ck14, and all cases that stained for S-100 protein (9 of 9) and
vimentin (13 of 13) were also positive. Based on our findings,
the balance of probabilities favors that MCBs may have a basal
or myoepithelial cell histogenesis and differentiation.Fundacão para a Ciência e a Tecnologia (FCT), Ministério da Ciência e Tecnologia (MCT) - SFRH/BD/5386/2001
The association between cardiovascular risk factors and major cardiovascular diseases decreases with increasing frailty levels in geriatric outpatients
BACKGROUND: Frailty marks a process of increasing dysregulation of physiological systems which increases the risk of adverse health outcomes. This study examines the hypothesis that the association between multiple cardiovascular risk factors (CVRF) and cardiovascular diseases (CVD) becomes stronger with increasing frailty severity. METHODS: Cross-sectional analysis of 339 older adults (55.2% women; aged 75.2 ± 9.1 years) from an outpatient geriatric clinic from a middle-income country. The frailty index (FI) was calculated as the proportion of 30 possible health deficits. We assessed hypertension, diabetes, obesity, dyslipidemia, sedentarism and smoking as CVRF (determinants) and myocardial infarction, stroke, heart failure as CVD. Poisson regression models adjusted for age, sex, and education was applied to estimate the association between frailty as well as CVRF (independent variables) with CVD (dependent variable). RESULTS: Of the 339 patients, 18,3% were frail (FI ≥ 0.25) and 32.7% had at least one CVD. Both frailty and CVRF were significantly associated with CVD (PR = 1.03, 95% CI 1.01 to 1.05; p = 0.001, and PR = 1.46, 95% 1.24 to 1.71; p < 0.001, respectively) adjusted for covariates. The strength of the association between CVRF and CVD decreased with increasing frailty levels, as indicated by a significant interaction term of frailty and CVRF (p < 0.001). CONCLUSION: Frailty and CVRF are both associated with CVD, but the impact of CVRF decreases in the presence of frailty. When confirmed in longitudinal studies, randomized controlled trials or causal inference methods like Mendelian randomization should be applied to assess whether a shift from traditional CVRF to frailty would improve cardiovascular outcome in the oldest old
Androgen responsive intronic non-coding RNAs
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
Writing 3D In vitro models of human tendon within a biomimetic fibrillar support platform
Tendinopathies are poorly understood diseases for which treatment remains challenging. Relevant in vitro models to study human tendon physiology and pathophysiology are therefore highly needed. Here we propose the automated 3D writing of tendon microphysiological systems (MPSs) embedded in a biomimetic fibrillar support platform based on cellulose nanocrystals (CNCs) self-assembly. Tendon decellularized extracellular matrix (dECM) was used to formulate bioinks that closely recapitulate the biochemical signature of tendon niche. A monoculture system recreating the cellular patterns and phenotype of the tendon core was first developed and characterized. This system was then incorporated with a vascular compartment to study the crosstalk between the two cell populations. The combined biophysical and biochemical cues of the printed pattern and dECM hydrogel were revealed to be effective in inducing human-adipose-derived stem cells (hASCs) differentiation toward the tenogenic lineage. In the multicellular system, chemotactic effects promoted endothelial cells migration toward the direction of the tendon core compartment, while the established cellular crosstalk boosted hASCs tenogenesis, emulating the tendon development stages. Overall, the proposed concept is a promising strategy for the automated fabrication of humanized organotypic tendon-on-chip models that will be a valuable new tool for the study of tendon physiology and pathogenesis mechanisms and for testing new tendinopathy treatments.The authors thank Hospital da Prelada (Porto, Portugal) for providing adipose tissue samples. The authors acknowledge the financial support from Project NORTE-01-0145-FEDER 000021 supported by Norte Portugal Regional Operational Program (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), the European Union Framework Program for Research and Innovation HORIZON 2020, under the Twinning Grant Agreement 810850-Achilles, and European Research Council Grant Agreement 772817 and 101069302, Fundação para a Ciência e a Tecnologia for the Ph.D. grant PD/BD/129403/2017 (to S.M.B.) financed through the doctoral program in Tissue Engineering, Regenerative Medicine and Stem Cells (TERM&SC), for Contract 2020.03410.CEECIND and 2022.05526.PTDC (to R.M.A.D.). The authors acknowledge Doctor Alberto Pardo for performing the rheology measurements of the PL bioink. The schematics in Figures 1, 2A, 4A, and 6A and Table of Contents graphic were created with BioRender.com
Screening for mutations in the GJB3 gene in Brazilian patients with nonsyndromic deafness
Abstract. Deafness is a complex disorder that is affected by a high number of genes and environmental factors. Recently, enormous progress has been made in nonsyndromic deafness research, with the identification of 90 loci and 33 nuclear and 2 mitochondrial genes involved (http://dnalab-www.uia.ac.be/dnalab/hhh/). Mutations in the GJB3 gene, encoding the gap junction protein connexin 31 (Cx31), have been pathogenically linked to erythrokeratodermia variabilis and nonsyndromic autosomal recessive or dominant hereditary hearing impairment. To determine the contribution of the GJB3 gene to sporadic deafness, we analysed the GJB3 gene in 67 families with nonsyndromic hearing impairment. A single coding exon of the GJB3 gene was amplified from genomic DNA and then sequenced. Here we report on three amino acid changes: Y177D (c.529T > G), 49delK (c.1227C > T), and R32W (c.144-146delGAA). The latter substitution has been previously described, but its involvement in hearing impairment remains uncertain. We hypothesize that mutations in the GJB3 gene are an infrequent cause of nonsyndromic deafness
How oogenesis analysis combined with dna barcode can help to elucidate taxonomic ambiguities: A polychaete study-based approach
Polychaetes are common in coastal and estuarine environments worldwide and constitute one of the most complex groups of marine invertebrates. The morpho-physiology of the female reproductive system (FRS) can be understood by using histological tools to describe reproductive cycle and gametogenesis paths and, among other purposes, aiming to identify and differentiate polychaete species. However, this histology-based approach is rarely combined with molecular tools, which is known to accurately delimitate species. In the same way, the description and understanding of oogenesis and vitellogenesis paths within polychaetes are lacking for most families, narrowing the range of its utility. Therefore, the present study aims to describe the oogenesis in three polychaete species common and abundant on the South American Atlantic coast (Laeonereis culveri, Scolelepis goodbodyi and Capitella biota) and investigate the utility of reproductive features and gametogenesis as a relevant associate knowledge to discriminate species, particularly useful for putative cryptic species, integrated with morphological and molecular data. In a first attempt, the results obtained herein allow the authors to describe two new subtypes of oogenesis, dividing it in extraovarian oogenesis type I and II and intraovarian type I and II. The results also demonstrate that the following histological characters of the FRS can be relevant for the separation of related species: a) oogenesis type, b) occurrence or absence of a true ovary, c) ovary tissue organization, d) type of accessory cells present, and e) oocyte morphology. Additionally, these histological features of FRS, when compared with correlated species studied under this scope, converge with the genetic data. The analysis of cytochrome oxidase I (COI) barcode sequences differentiates between North and South American Atlantic populations of L. culveri (16.78% genetic distance), while in S. goodbodyi and C. biota it discriminates them from their congeneric species. These results highlight theOs poliquetas são comuns em ambientes costeiros e estuarinos em todo o mundo e constituem um dos grupos mais complexos de invertebrados marinhos. A morfo-fisiologia do sistema reprodutor feminino (FRS) pode ser compreendida por meio de ferramentas histológicas para identificar e diferenciar estes anelÃdeos. No entanto, essa abordagem histológica raramente é combinada com ferramentas moleculares, amplamente conhecidas por delimitar espécies congenéricas ou crÃpticas com maior precisão. Do mesmo modo, a descrição e o entendimento da oogênese e vitelogênese dentre os poliquetas, para a maioria das famÃlias, é ainda limitado. Portanto, o presente estudo tem como objetivo descrever a oogênese em três espécies de poliquetas comuns e abundantes na costa sul-americana (Laeonereis culveri, Scolelepis goodbodyi e Capitella biota) e investigar a utilidade das caracterÃsticas reprodutivas e da gametogênese como um conhecimento associado relevante para discriminar espécies, particularmente útil para espécies crÃpticas putativas, integradas a dados morfológicos e moleculares. Os resultados aqui obtidos permitiram descrever dois novos subtipos de oogênese, dividindo-a em oogênese extra-ovariana dos tipos I e II e intra-ovariana dos tipos I e II. Os resultados também demonstram que os seguintes caracteres histológicos do FRS podem ser relevantes para a separação de espécies relacionadas: a) tipo de oogênese, b) presença ou ausência de um ovário verdadeiro, c) organização tissular ovariana, d) tipo de células acessórias presentes e, e) morfologia do ovócito. Além disso, essas caracterÃsticas histológicas do FRS, quando comparadas à s espécies correlatas estudadas sob esse escopo, convergem com os dados genéticos separando espécies putativas e congenéricas. As análises com DNA barcode demonstraram que em L. culveri é possÃvel diferenciar as populações atlânticas Norte e Sul-americanas (16,78% de distância genética), enquanto para S. goodbodyi e C. biota fica evidente sua distinção com espécies congenéricas. Esses resultados destacam a importância da abordagem com múltiplas ferramentas e mostram que tanto a histologia quanto a histo-fisiologia do FRS e o DNA barcode podem ser usados para identificar e discriminar espécies crÃpticas e potencialmente crÃpticas, o que geralmente não é possÃvel quando se utilizam apenas caracteres morfológicos. Além disso, esses caracteres também podem ser úteis na diferenciação de espécies relacionadas e / ou populações geograficamente distintas desses poliquetas.The authors would like to thank IB/UNICAMP, IO/USP and CEBIMar/USP for providing logistic support. In addition, the authors would like to thank the CBMA and the IB-S for the technical support. This work was supported by the FAPESP (Grants no 2011/50317-5, 2015/25623-6, 2017/06167-5) and CNPq through a productivity grant to A.C.Z.A (306534/2015-0). M.A.L.T was supported by a PhD fellowship (SFRH/BD/131527/2017) from FCT. P.E.V. was supported by a Post-Doctoral Fellowships (BPD1/next-sea/2018, NORTE-01-0145-FEDER-000032). F.O.C. and the University of Minho contribution was supported by the strategic programme UID/BIA/04050/2013 POCI-01-0145-FEDER-007569
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