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- ERO1-independent production of H2O2 within the endoplasmic reticulum fuels Prdx4-mediated oxidative protein foldingPublication . Konno, Tasuku; Melo, Eduardo Pinho; Lopes, Carlos; Mehmeti, Ilir; Lenzen, Sigurd; Ron, David; Avezov, EdwardThe endoplasmic reticulum (ER)-localized peroxiredoxin 4 (PRDX4) supports disulfide bond formation in eukaryotic cells lacking endoplasmic reticulum oxidase 1 (ERO1). The source of peroxide that fuels PRDX4-mediated disulfide bond formation has remained a mystery, because ERO1 is believed to be a major producer of hydrogen peroxide (H2O2) in the ER lumen. We report on a simple kinetic technique to track H2O2 equilibration between cellular compartments, suggesting that the ER is relatively isolated from cytosolic or mitochondria! H2O2 pools. Furthermore, expression of an ER-adapted catalase to degrade lumenal H2O2 attenuated PRDX4-mediated disulfide bond formation in cells lacking ERO1, whereas depletion of H2O2 in the cytosol or mitochondria had no similar effect. ER catalase did not effect the slow residual disulfide bond formation in cells lacking both ERO1 and PRDX4. These observations point to exploitation of a hitherto unrecognized lumenal source of H2O2 by PRDX4 and a parallel slow H2O2-independent pathway for disulfide formation.
- Using remote sensing as a support to the implementation of the European Marine Strategy Framework Directive in SW PortugalPublication . Cristina, Sónia; Icely, John; Goela, Priscila; Angel DelValls, Tomás; Newton, AliceThe exclusive economic zones (EEZ) of coastal countries are coming under increasing pressure from various economic sectors such as fishing, aquaculture, shipping and energy production. In Europe, there is a policy to expand the maritime economic sector without damaging the environment by ensuring that these activities comply with legally binding Directives, such as the Marine Strategy Framework Directive (MSFD). However, monitoring an extensive maritime area is a logistical and economic challenge. Remote sensing is considered one of the most cost effective, methods for providing the spatial and temporal environmental data that will be necessary for the effective implementation of the MSFD. However, there is still a concern about the uncertainties associated with remote sensed products. This study has tested how a specific satellite product can contribute to the monitoring of a MSFD Descriptor for "good environmental status" (GES). The results show that the quality of the remote sensing product Algal Pigment Index 1 (API 1) from the MEdium Resolution Imaging Spectrometer (MERIS) sensor of the European Space Agency for ocean colour products can be effectively validated with in situ data from three stations off the SW Iberian Peninsula. The validation results show good agreement between the MERIS API 1 and the in situ data for the two more offshore stations, with a higher coefficient of determination (R-2) of 0.79, and with lower uncertainties for the average relative percentage difference (RPD) of 24.6% and 27.9% and a root mean square error (RMSE) of 0.40 and 0.38 for Stations B and C, respectively. Near to the coast, Station A has the lowest R-2 of 0.63 and the highest uncertainties with an RPD of 112.9% and a RMSE of 1.00. It is also the station most affected by adjacency effects from the land: when the Improved Contrast between Ocean and Land processor (ICOL) is applied the R-2 increases to 0.77 and there is a 30% reduction in the uncertainties estimated by RPD. The MERIS API 1 product decreases from inshore to offshore, with higher values occurring mainly between early spring and the end of the summer, and with lower values during winter. By using the satellite images for API 1, it is possible to detect and track the development of algal blooms in coastal and marine waters, demonstrating the usefulness of remote sensing for supporting the implementation of the MSFD with respect to Descriptor 5: Eutrophication. It is probable that remote sensing will also prove to be useful for monitoring other Descriptors of the MSFD.
- The shading sign: is it exclusive of endometriomas?Publication . Dias, Joao Lopes; Veloso Gomes, Filipe; Lucas, Rita; Cunha, Teresa MargaridaTo investigate if the shading sign is an exclusive MRI feature of endometriomas or endometrioid tumors, and to analyze its different patterns. Three hundred and fourty six women with adnexal masses who underwent 1.5/3-T MRI were included in this retrospective, board-approved study. The shading sign was found in 56 patients, but five cases were excluded due to lack of imaging follow-up or histological correlation. The final sample included 51 women. The type of tumor and the pattern of shading were recorded for each case. Thirty endometriomas and five endometrioid carcinomas were found. The remaining 16 cases corresponded to other benign and malignant tumors. The overall sensitivity, specificity, positive predictive value, and negative predictive value were 73%, 93%, 59%, and 96%, respectively. Restricting the analysis to cystic lesions without solid or fat component, sensitivity, specificity, positive predictive value, and negative predictive value were 73%, 96%, 94%, and 80%. Five shading patterns were identified: layering (15.7%), liquid-liquid level (11.8%), homogenous (45.1%), heterogeneous (11.8%), and focal/multifocal shading within a complex mass (19.6%). No significant correlation was found between these patterns and the type of tumor. The shading sign is not exclusive of endometriomas or endometrioid tumors. Homogenous shading was the most prevalent pattern in endometriomas and half of the cases with focal/multifocal shading within a complex mass were endometrioid carcinomas.
- Hepatitis C treatment in a district HospitalPublication . Espírito Santo, Margarida; Guerreiro, Luisa; Nascimento, TâniaThe aim of this study was the characterization of patients with Hepatitis C (HCV) under treatment. Patients included in this study were followed in a Portuguese District Hospital between January 2012 and September 2014, have received treatment for HCV and who had at least one infectiology consultation in this period. Data were collected from the hospital computer system, and patient´s data were collected anonymously, without patient identification. Data analysis was performed using SPSS v22.0. Were included in this study 87 patients who met the inclusion criteria, 75% (n=65) were males and 25% (n=22) female, with a mean age of 45±10 years. Most patients included in this study were Portuguese, resident in the Hospital district and nearby districts. Patients were diagnosed with HCV with a mean age of 3311 years, were followed on average for 53.5 years in this Hospital, and were diagnosed with HCV on average 126.9 years ago. Among these patients, 44% (n=38) had genotype 1, 2% (n=2) genotype 2, 17% (n=15) genotype 3, 13% (n=11) genotype 4 and 24% (n=21) with unknown genotype. Most frequent treatment regimens used by patients included in the study were the association of pegylated interferon alfa 2b (100mcg/week) and ribavirin (1000 mg/day) (52%; n=45); pegylated interferon alpha 2a (180mcg/week) and ribavirin (1000 mg/day) (42%; n=36). Other associations were used but less frequently: pegylated interferon alfa 2a + ribavirin + boceprevir (2%; n=2); pegylated interferon alfa 2b + ribavirin + boceprevir (3%; n=3); and pegylated interferon alfa 2a + ribavirin + telaprevir (1%; n=1). Among included patients, 55 (63%) have performed, to date, one treatment for HCV, 19 (22%) have performed two treatments for HCV (using two different regimens or by using the same regimen twice), 9 (10%) already underwent treatment three times, 3 (3%) already underwent treatment four times and only one patient (1%) has conducted five treatments for HCV. Excluding patients who were receiving treatment at the time of data collection (September 2014), the average length of all other treatments performed by the patients was 82 months, and most (40%; n=51) of treatments performed by patients had a duration from 6 to 9 months. From the results, the standard treatment for patients with HCV appears to be in accordance with the existing guidelines for the treatment of this pathology. In the future it would be advisable further analysis and extended to other hospitals to assess the degree of compliance with currently existing national guidelines for the treatment of this pathology.
- Pelagic population dynamics of Aurelia sp in French Mediterranean lagoonsPublication . Marques, Raquel; Albouy-Boyer, Severine; Delpy, Floriane; Carre, Claire; Le Floc'h, Emilie; Roques, Cecile; Molinero, Juan-Carlos; Bonnet, DelphineThe pelagic dynamics of the cosmopolitan scyphozoan Aurelia sp. was investigated in three French Mediterranean lagoons, Thau, Berre and Bages-Sigean, which harbour resident populations. The annual cycles showed a common univoltine pattern in all lagoons where the presence of pelagic stages in the water column lasted similar to 8 months. Field observations showed a release of ephyrae in winter time followed by pronounced growth between April and July, when individuals reached the largest sizes, before disappearing from the water column. Maximum abundance of ephyrae and medusae were registered in Thau. Medusae abundance attained a maximum of 331 ind 100 m(-3) in Thau, 18 ind 100 m(-3) in Berre and 7 ind 100 m(-3) in Bages-Sigean lagoons. Temperature and zooplankton abundance appeared as leading factors of growth, where Bages-Sigean showed the population with higher growth rates (2.66 mm day(-1)) and maximum size (32 cm), followed by Thau (0.57-2.56 mm day(-1); 22.4 cm) and Berre (1.57-2.22 mm day(-1); 17 cm). The quantification of environmental windows used by the species showed wider ranges than previously reported in the Mediterranean Sea, which suggests a wide ecological plasticity of Aurelia spp. populations in north-western Mediterranean lagoons.
- How diabetics’ patients identify their medicines?Publication . Espírito Santo, Margarida; Nascimento, Tânia; Newman, JeffThe main goal of this study was the characterization of diabetic patients´ knowledge in the identification of medicines, respectively the drug´s name, drug´s strength, and therapeutic indication. A cross-sectional study was developed at a specialized medical center in the diabetes area. Only patients that accepted to participate in this research and who gave their consent in writing before the start of the study were enrolled. In the study they were included patients aged 18 years and older, with diagnosis of diabetes mellitus, and using at least one medicine. Data collection was conducted through structured interviews, which was held during a consultation in a systematic way by completion of a questionnaire. Were included in this study one hundred and seven (107) patients, 41.1% female and 58.9% male, aged between 35 and 88 years, with a mean age of 65.6±10.5 years. The most prevalent health problems, beside diabetes mellitus, were hypertension (83.2%) and dyslipidaemia (74.8%), with a mean of 4.7±1.9 health problems per patient. Each patient was using a mean of 6.9±2.9 medicines and 0.2±0.4 food supplements per day. The therapeutic group often used was C (Cardiovascular System), A (Alimentary Tract and Metabolism) and N (Nervous System) with respectively 33.8%, 32.6% and 11.5%. Patients included in this study could not indicate the name of the medicines they were taking in 50% of the medicines, but were able to read the name of the medicine in most (96.5%) of them. When patients were questioned regarding drug´s strength only in about 25% of the medicines they managed to indicate the respective value. In most medicines (67.7%), patients were able to indicate the correct therapeutic indication for each medicine, although in 16.8% of medicines patients did not know the respective therapeutic indication, in 9.2% of medicines the information about therapeutic indication was incomplete, and in 6.3% of medicines patients have indicated an incorrect therapeutic indication. The results obtained indicate that patients have some lack of ability in the basic identification of the medicines used. In the future it will be desirable to perform a more extensive analysis that includes further variables related to the knowledge of the patients about medicines, including instructions of use, possible side effects and storage conditions, in order to be able to establish an action plan that can provide patients with more and better skills to achieve a responsible use of medicines.
- Stanniocalcin 1 effects on the renal gluconeogenesis pathway in rat and fishPublication . Schein, Vanessa; Kucharski, Luiz C.; M Guerreiro, Pedro; Martins, Tiago Leal; Morgado, Isabel; Power, Deborah M.; Canario, Adelino V. M.; da Silva, Roselis S. M.The mammalian kidney contributes significantly to glucose homeostasis through gluconeogenesis. Considering that stanniocalcin 1 (STC1) regulates ATP production, is synthesized and acts in different cell types of the nephron, the present study hypothesized that STC1 may be implicated in the regulation of gluconeogenesis in the vertebrate kidney. Human STC1 strongly reduced gluconeogenesis from C-14-glutamine in rat renal medulla (MD) slices but not in renal cortex (CX), nor from C-14-lactic acid. Total PEPCK activity was markedly reduced by hSTC1 in MD but not in CX. Pck2 (mitochondrial PEPCK isoform) was down-regulated by hSTC1 in MD but not in CX. In fish (Dicentrarchus labrax) kidney slices, both STC1-A and -B isoforms decreased gluconeogenesis from C-14-acid lactic, while STC1-A increased gluconeogenesis from C-14-glutamine. Overall, our results demonstrate a role for STC1 in the control of glucose synthesis via renal gluconeogenesis in mammals and suggest that it may have a similar role in teleost fishes. (C) 2015 Elsevier Ireland Ltd. All rights reserved.
- European Sea Bass (Dicentrarchus labrax) immune status and disease resistance are impaired by arginine dietary supplementationPublication . Azeredo, Rita; Perez-Sanchez, Jaume; Sitja-Bobadilla, Ariadna; Fouz, Belen; Tort, Lluis; Aragao, Claudia; Oliva-Teles, Aires; Costas, BenjaminInfectious diseases and fish feeds management are probably the major expenses in the aquaculture business. Hence, it is a priority to define sustainable strategies which simultaneously avoid therapeutic procedures and reinforce fish immunity. Currently, one preferred approach is the use of immunostimulants which can be supplemented to the fish diets. Arginine is a versatile amino acid with important mechanisms closely related to the immune response. Aiming at finding out how arginine affects the innate immune status or improve disease resistance of European seabass (Dicentrarchus labrax) against vibriosis, fish were fed two arginine-supplemented diets (1% and 2% arginine supplementation). A third diet meeting arginine requirement level for seabass served as control diet. Following 15 or 29 days of feeding, fish were sampled for blood, spleen and gut to assess cell-mediated immune parameters and immune-related gene expression. At the same time, fish from each dietary group were challenged against Vibrio anguillarum and survival was monitored. Cell-mediated immune parameters such as the extracellular superoxide and nitric oxide decreased in fish fed arginine-supplemented diets. Interleukins and immune-cell marker transcripts were down-regulated by the highest supplementation level. Disease resistance data were in accordance with a generally depressed immune status, with increased susceptibility to vibriosis in fish fed arginine supplemented diets. Altogether, these results suggest a general inhibitory effect of arginine on the immune defences and disease resistance of European seabass. Still, further research will certainly clarify arginine immunomodulation pathways thereby allowing the validation of its potential as a prophylactic strategy.
- Mediterranean Outflow and surface water variability off southern Portugal during the early Pleistocene: A snapshot at Marine Isotope Stages 29 to 34 (1020-1135 ka)Publication . Voelker, Antje H. L.; Salgueiro, Emilia; Rodrigues, Teresa; Jiménez-Espejo, Francisco J.; Bahr, Andre; Alberto, Ana; Loureiro, Isabel; Padilha, Maria; Rebotim, Andreia; Roehl, UrsulaCentennial-to-millennial scale records from IODP Site U1387, drilled during IODP Expedition 339 into the Faro Drift at 558 m water depth, now allow evaluating the climatic history of the upper core of the Mediterranean Outflow (MOW) and of the surface waters in the northern Gulf of Cadiz during the early Pleistocene. This study focuses on the period from Marine Isotope Stages (MIS) 29 to 34, i.e. the interval surrounding extreme interglacial MIS 31. Conditions in the upper MOW reflect obliquity, precession and millennial-scale variations. The benthic delta O-18 signal follows obliquity with the exception of an additional, smaller delta O-18 peak that marks the MIS 32/31 transition. Insolation maxima (precession minima) led to poor ventilation and a sluggish upper MOW core, whereas insolation minima were associated with enhanced ventilation and often also increased bottom current velocity. Millennial-scale periods of colder sea-surface temperatures (SST) were associated with short-term maxima in flow velocity and better ventilation, reminiscent of conditions known from MIS 3.A prominent contourite layer, coinciding with insolation cycle 100, was formed during MIS 31 and represents one of the few contourites developing within an interglacial period. MIS 31 surface water conditions were characterized by an extended period (1065-1091 ka) of warm SST, but SST were not much warmer than during MIS 33. Interglacial to glacial transitions experienced 2 to 3 stadial/interstadial cycles, just like their mid-to-late Pleistocene counterparts. Glacial MIS 30 and 32 recorded periods of extremely cold (<12 degrees C) SST that in their climatic impact were comparable with the Heinrich events of the mid and late Pleistocene. Glacial MIS 34, on the other hand, was a relative warm glacial period off southern Portugal. Overall, surface water and MOW conditions at Site U1387 show a strong congruence with Mediterranean climate, whereas millennial-scale variations are closely linked to North Atlantic circulation changes. (C) 2015 Elsevier B.V. All rights reserved.
- Metatranscriptomes reveal functional variation in diatom communities from the Antarctic PeninsulaPublication . Pearson, Gareth; Lago-Lestón, Asunción; Canovas, Fernando; Cox, C. J.; Verret, Frédéric; Lasternas, Sebastian; Duarte, Carlos M.; Agusti, Susana; Serrao, Ester A.Functional genomics of diatom-dominated communities from the Antarctic Peninsula was studied using comparative metatranscriptomics. Samples obtained from diatom-rich communities in the Bransfield Strait, the western Weddell Sea and sea ice in the Bellingshausen Sea/Wilkins Ice Shelf yielded more than 500K pyrosequencing reads that were combined to produce a global metatranscriptome assembly. Multi-gene phylogenies recovered three distinct communities, and diatom-assigned contigs further indicated little read-sharing between communities, validating an assembly-based annotation and analysis approach. Although functional analysis recovered a core of abundant shared annotations that were expressed across the three diatom communities, over 40% of annotations (but accounting for <10% of sequences) were community-specific. The two pelagic communities differed in their expression of N-metabolism and acquisition genes, which was almost absent in post-bloom conditions in the Weddell Sea community, while enrichment of transporters for ammonia and urea in Bransfield Strait diatoms suggests a physiological stance towards acquisition of reduced N-sources. The depletion of carbohydrate and energy metabolism pathways in sea ice relative to pelagic communities, together with increased light energy dissipation (via LHCSR proteins), photorespiration, and NO3 uptake and utilization all pointed to irradiance stress and/or inorganic carbon limitation within sea ice. Ice-binding proteins and cold-shock transcription factors were also enriched in sea ice diatoms. Surprisingly, the abundance of gene transcripts for the translational machinery tracked decreasing environmental temperature across only a 4 degrees C range, possibly reflecting constraints on translational efficiency and protein production in cold environments.
- A new analysis method for structural failure evaluationPublication . Estêvão, João Manuel Carvalho; Oliveira, Carlos SousaThere are many possible approaches for structural failure evaluation which uses different nonlinear structural analysis methods. For computer implementation purposes, some important differences between them are the results precision, the amount of computer memory needed and computer processing time. For solving practical problems, a compromise between accuracy and computational effort is needed. In this work, a new method is presented for linear and nonlinear structural analysis. The new developed method was named Fibre Contact Element Method (FCEM). In the proposed method, structures are divided in a mesh of several small rectangular block elements (neighbour blocks do not need to be aligned). These elements are divided in several micro fibre elements. Fibres belonging to neighbour blocks are connected between contact points. Two degrees of freedom are considered per contact point and three degrees of freedom are considered for each block (in a 2D model). The elemental block stiffness matrix is obtained from the assembly of fibre stiffness matrix. A static matrix condensation is preformed to reduce the block stiffness matrix dimension. The elasticity and plasticity is concentrated on each fibre element. Global nonlinear response can result from flexural or from shear fibre cracking or yielding. In this work, comparisons between numerical and analytical results are presented. The new method seems to be accurate and fast enough for solving practical problems, namely for seismic damage assessment. Results seem to demonstrate that FCEM can be a valid option for using in structural failure evaluation.
- O western entre a história e o mito: a arte do oeste americano no western de HollywoodPublication . Carrega, JorgeSurgida no início do séc. XIX, a arte sobre o Oeste americano, constitui parte de um folclore que transformou o cowboy no mais influente símbolo da América nos séculos XIX e XX. A influência de artistas como Frederic Remington e Charles Russell, na cultura popular dos EUA, é particularmente visível no western clássico de Hollywood. Ao assimilar os valores formais e ideológicos que caracterizam a obra destes artistas, cineastas como John Ford, Raoul Walsh e John Sturges, realizaram uma verdadeira simbiose entre o cinema e o primeiro movimento artístico americano. No entanto, o western de Hollywood nunca foi um mero exercício estético, constituindo uma expressão das profundas transformações que a sociedade americana sofreu ao longo do século XX.
- A transcriptome resource for the copepod Calanus glacialis across a range of culture temperaturesPublication . A Ramos, Ana; Weydmann, A.; Cox, C. J.; Canario, A.V.M.; A, Serrão; Pearson, G. A.The copepod Calanus glacialis plays a key role in the Arctic pelagic ecosystem. Despite its ecological importance and ongoing climate changes, limited knowledge at the genomic level has hindered the understanding of the molecular processes underlying environmental stress responses and ecological adaptation. Transcriptome data was generated from an experiment with C glacialis copepodite (CV) subjected to five different temperatures. We obtained a total of 512,352 high-quality 454 pyrosequencing reads, which were assembled into 55,562 contigs distributed in 128 KEGG pathways. Functional analysis revealed numerous genes related to diverse biological functions and processes, including members of all major conserved signaling pathways. Comparative analysis of acclimated individuals to experimental temperatures has provided information about gene variations observed in several pathways (e.g. genes involved in energy, lipid and amino acid metabolism were shown to be down-regulated with increasing temperatures). These mRNA sequence resources will facilitate further studies on genomics and physiology-driven molecular processes in C glacialis and related species. (C) 2015 Elsevier B.V. All rights reserved.
- As empresas vitivinícolas e o desenvolvimento do enoturismo: o caso da região do Alentejo, PortugalPublication . Lavandoski, Joice; Vargas-Sánchez, Alfonso; Silva, João Albino; Valle, Patrícia Oom doEsta Tese aborda a questão da mudança estratégica das empresas produtoras de vinho que se tornam também empresas ligadas à atividade turística, através do desenvolvimento do enoturismo. O objetivo geral desta pesquisa é desenvolver e testar um modelo de análise que permita identificar causas e efeitos do desenvolvimento do enoturismo nas empresas produtoras de vinho. Utilizando técnicas estatísticas apoiadas na Modelação de Equações Estruturais (SEM). Este modelo aproxima duas perspectivas teóricas diferentes, porém complementares. A abordagem de Capacidades Dinâmicas conduz a um ponto de vista intraorganizacional (fatores endógenos) e a Teoria Institucional proporciona uma análise interorganizacional (fatores exógenos) do contexto institucional. A revisão bibliográfica da investigação permitiu adaptar escalas de medida validadas, sobretudo de estudos turísticos, que foram utilizadas num questionário aplicado em 40 empresas produtoras de vinho com a componente de enoturismo no Alentejo, Portugal. O modelo permitiu revelar que as capacidades dinâmicas e as pressões institucionais influenciam o desenvolvimento do enoturismo que, por sua vez, tem efeito na legitimidade social e no desempenho organizacional. A capacidade de aprender e a força normativa são as variáveis com maior poder explicativo do desenvolvimento do enoturismo e, também, tem maior incidência no desempenho das empresas analisadas. Os resultados obtidos permitem concluir que, através do desenvolvimento do enoturismo as empresas produtoras de vinho criam, ampliam e modificam os seus processos, construindo e utilizando capacidades dinâmicas, enquanto os fatores institucionais moldam o seu comportamento e conferem legitimidade social para as ações e práticas de enoturismo, além de melhorar o seu desempenho organizacional. As conclusões apuradas servem de ferramentas norteadoras para implantação, avaliação e direcionamento estratégico do enoturismo para o sector empresarial, principalmente aos gestores e diretores de empresas produtoras de vinho que tenham a componente de enoturismo no negócio ou que pretendem desenvolvê-la. O estudo também destaca o papel dos gestores e dos recursos humanos no processo de mudança organizacional, em termos estratégicos e decisórios. E fornece reflexões sobre a relação entre uma rota de vinho e as empresas, as quais tem consequências significativas no enoturismo. A criação deste modelo fornece ao sector empresarial vitivinícola uma ferramenta que lhes permite diagnosticar e/ou desenvolver o enoturismo, alterar processos e delinear estratégias de atuação no segmento do enoturismo, em conformidade com o quadro institucional envolvente e aproveitando as oportunidades de mercado.
- O perfil do enoturista: o caso portuguêsPublication . Lameiras, Edgar Teles Marques Salgado; Silva, João Albino; Mendes, Júlio; Valle, Patrícia Oom doO enoturismo adquire importância crescente para as regiões vitivinícolas, enquanto setor que promove o crescimento e origina lucro. Contudo, o enoturismo permanece pouco desenvolvido e uma das causas apontadas consiste na falta de investigação sobre o comportamento e características do visitante da adega. O presente trabalho tem como principais objetivos a determinação do perfil demográfico e psicográfico dos visitantes que se deslocam às quintas, adegas e caves e a segmentação dos enoturistas. Para alcançar os objetivos indicados, construiu-se um instrumento de pesquisa, tendo em vista a obtenção de dados quantitativos e qualitativos sobre o enoturista e os seus hábitos, comportamentos, preferências e motivações. O questionário realizado foi aplicado aos turistas que se deslocavam às quintas, adegas e caves, das 12 rotas de vinho existentes em Portugal. Os dados foram sujeitos a testes paramétricos e a técnicas estatísticas multivariadas, de modo a obterem-se diferentes clusters. Os resultados mostram que os turistas foram motivados para a sua visita por uma variedade de fatores, entre os quais a prova e a compra de vinhos ou a participação num curso de vinhos. Verificou-se que os enoturistas são maioritariamente de nacionalidade portuguesa, do sexo masculino, com um nível elevado de educação e com um rendimento mensal médio acima dos 1251€. Obtiveram-se quatro segmentos de enoturistas, que foram designados por: o turista apaixonado pelo vinho, o turista com curiosidade pelo vinho, o turista interessado pelo vinho e o turista indiferente. As conclusões indicam que o aumento do conhecimento sobre os enoturistas e suas finalidades e motivações para visitar a região permite melhorar a satisfação e a interação com eles, apoiando estratégias de marketing, de modo a reforçar a motivação e o apelo dos vinhos e das quintas.
- Loss of Par3 leads to aberrant divisions and faster mitotic progression in differentiating primary murine keratinocytesPublication . Gomes, Martim Carvalho Fernandes Dias; Iden, Sandra; Tavares, ÁlvaroTodas as células que constituem o organismo foram geradas através de sucessivas divisões celulares a partir de uma única célula: o ovo fertilizado. Durante o desenvolvimento e estado adulto existe um controlo exato dos processos de divisão, polaridade e destino celular de forma a produzir, controlar e manter os diferentes tipos de tecido que constituem um organismo adulto. Entre estes, o tecido epitelial é de particular interesse pois é responsável pela constituição da maioria dos órgãos nos mamíferos nos mais diversos contextos. Esta multiplicidade implica um leque alargado de funções diferenciadas e extremamente especializadas que só podem ser atingidas através de um grau de organização elevado por partes das células epiteliais de modo a gerar e manter a arquitetura do tecido. Paralelamente, a grande maioria dos cancros humanos provêm de tecidos epiteliais. De facto a perda da polaridade e a desorganização tecidular são pré-requisitos para a formação de tumores epiteliais e sua progressão. A polaridade apico-basal assenta na ação concertada de proteínas que medeiam a polaridade e que são controladas por sinais externos e internos, tais como factores de crescimento ou sinais do citoesqueleto. Essas proteínas organizam-se em três complexos distintos: Scribbles, Par e Crumbs que foram identificados em invertebrados e que são conservados em mamíferos tanto estrutural como funcionalmente. A disrupção de qualquer um destes complexos já foi demonstrada contribuir para génese de tumores nos mais diversos contextos. Dos três complexos, o PAR tem a função mais alargada, estando envolvido na polaridade apico-basal, polarização neuronal e migração direcionada de células T. O complexo PAR é constituído por duas proteínas Par (partitioning defective), Par3 e Par6 com funções estruturais e aPKC (atypical Protein Kinase C), uma serina-treonina cinase. Par3/Par6/aPKC conseguem formar um complexo ternário, no entanto Par3 dissocia-se do mesmo após fosforilação por aPKC. O complexo Par está envolvido em decisões de destino celular pois transmite sinais apicais para regular o alinhamento e orientação do fuso mitótico. Durante uma divisão celular orientada, a célula tem de alinhar o eixo de divisão paralela ou perpendicularmente em relação ao eixo do tecido. Esta diferente orientação está acoplada à regulação do destino celular. Se ambas as células filha têm o mesmo destino designa-se por divisão celular simétrica, ou no caso das células filhas terem destinos diferentes é designado por divisão celular assimétrica. A orientação da divisão envolve o alinhamento do fuso mitótico como o eixo de polaridade celular. Proteínas de polaridade como Par3, aPKC e Par6 permitem a transdução de estímulos externos e sinais da maquinaria intracelular para estabelecer a polaridade no interior da célula. Tecidos que proliferam e se autorrenovam mantêm a homeostasia através do rácio entre a manutenção de células estaminais e a geração de células filhas que se comprometem numa via de diferenciação. Sabemos hoje, que as células estaminais podem ser determinantes e até causativas na formação de tumores e que decisões de destino celular defetivas podem contribuir para o comportamento anormal das células estaminais. A pele é o maior órgão dos mamíferos e representa a primeira linha de defesa do organismo contra agressões externas. É composta por dois compartimentos: um à superfície forrado por epitélio, designado por epiderme e outro mais profundo com propriedades conectivas e de nutrição designado por derme. A epiderme é um epitélio estratificado com capacidade de auto renovação. Numa epiderme normal e saudável, existe um balanço entre a proliferação celular que ocorre na camada basal, a diferenciação das camadas suprabasais e a morte celular. Alterações neste balanço podem resultar em processos de renovação e reparação celular deficientes ou aberrantes que podem em último caso, levar ao envelhecimento da pele, hiperplasias ou até mesmo cancro. Na verdade, a epiderme está em contacto direto com diversos fatores oncogénicos como agentes patogénicos, químicos e radiação ultravioleta (UV) que estão associados ao aparecimento de neoplasias. No entanto uma questão que continua em aberto é como a alteração da polaridade pode alterar este equilíbrio, especialmente através dos processos de divisão celular. Foi anteriormente demonstrado que a perda da proteína Par3 na epiderme murina resultava em fenótipos diferenciados dependendo do contexto. Através de um modelo clássico de indução e promoção da génese de tumores através de DMBA/TPA, a perda de Par3 resultou num menor número e tamanho de papilomas (tumores benignos epiteliais), mediados pela localização errónea da cinase aPKC fora das junções intercelulares, acompanhados por apoptose e redução da proliferação celular. Estes resultados sugeriram uma função oncogénica para Par3 na epiderme murina. Porém os papilomas que se formaram demonstraram-se muito invasivos. Inesperadamente a perda de Par3 também predispôs os animais para a formação de queratoacantoma, um tipo de neoplasia muito rara em M. musculus mas frequentemente observadas em humanos. Desta forma Par3 atua na epiderme murina tanto como oncogene ou gene supressor de tumores dependendo do contexto. Considerando o papel do complexo Par no destino celular e génese de tumores, o objectivo deste trabalho é estudar o efeito da perda de Par3 sobre a divisão celular e o seu contributo para a génese de tumores em queratinócitos epidérmicos murinos durante homeostasia e stress mediado por radiação ultravioleta. Neste estudo observámos que a perda de Par3 em queratinócitos primários predispôs para divisões celulares aberrantes em condições de diferenciação. Paralelamente, os queratinócitos Par3 KO que progrediram através de uma divisão celular correta, demonstraram passar menos tempo em mitose que os controlos, sugerindo uma progressão mitótica mais rápida. Demonstrámos igualmente que a indução da diferenciação leva a amplificação de centrossomas e aneuploidia in vitro mas independentemente do genótipo. Observou-se também que, em condições de não diferenciação a perda de Par3 levou ao aparecimento de fuso mitóticos multipolares. De seguida foi avaliado o ciclo celular nas duas populações de queratinócitos: as célulasPar3 KO demonstraram um perfil de FACS comparável ao dos controlos aquando da diferenciação, sugerindo um perfil de diferenciação precoce. A perda de Par3 predispôs as células primárias para uma mais rápida progressão mitótica após irradiação por UV. Ao analisarmos a área do núcleo, as células Par3KO demonstraram ter uma maior área nuclear quando comparadas com os controlos nas condições de não diferenciação. Analisou-se a resposta ao dano no ADN através do marcador 53BP1. Em condições de não diferenciação após irradiação das células, os queratinócitos Par3 KO demostraram responder ao dano no ADN de forma diferenciada quando comparados com os controlos. Nas secções de queratoacantomas das nossas experiências in vivo observámos divisões celulares assimétricas, simétricas e aberrantes. Este estudo aponta para uma possível nova função de Par3 na regulação da progressão mitótica durante a homeostasia e stress induzido por radiação UV. Os queratoacantomas são tumores de crescimento rápido que advêm de áreas da pele exposta à radiação solar, no entanto a sua etiologia é pouco conhecida. As nossas observações contribuem para a compreensão do impacto da perda de polaridade na homeostasia tegumentar e abrem possíveis vias para o entendimento da génese dos queratoacantomas.
- Neuroendocrinology of cooperation: the role of neuropeptides on the modulation of mutualistic behaviour of the Indo-Pacific Cleaner Wrasse (Labroides dimidiatus)Publication . Cardoso, Sónia Cristina Cobra; Soares, Marta; Oliveira, Rui; Canario, Adelino V. M.Interspecific cleaning interactions are a classical textbook example of mutualistic cooperation. One of the most notorious cleaning mutualisms involve the Indo-Pacific Bluestreak cleaner wrasse Labroides dimidiatus, which are known to interact with an average of 2300 visitor reef fish per day. In contrast to the increasing knowledge on the functional aspects of cleaning mutualisms in the last decades, their underlying physiological mechanisms are still relatively rare. One major class of neuromodulators that is involved in the control of social behaviour and that seems to be co-opted for the regulation of cleaning behaviour is a group of nonapeptides of the arginine vasopressin /oxytocin family (AVP/OT). The general aim of this study is to attempt to link functional aspects of decision-making underlying the cleaning behaviour with their proximate mechanisms, namely to determine the contribution of the neuropeptides arginine vasotocin (AVT) and isotocin (IT) for the regulation of adjustments of individual cleaner wrasses’ behavioural output. This study yielded several findings. First, I tested the influence of AVT upon the cleaners’ ability to solve two different problems that in principle differ in ecological relevance and are associated with two different memory circuits and found that AVT affected the learning competence of cleaners as individual performance showed distinct response selectivity to AVT dosage levels. However, only in the ecologically relevant task was their learning response improved by blocking AVT via treatment with the antagonist Manning compound. Next I examined if neuropeptides may be implicated in the mechanisms underlying the adjustment of individuals to the existence of partner control mechanisms in cooperative interactions between unrelated individuals and discovered that solely the experimental transient higher dosage of AVT led to a decrease of cleaners’ willingness to feed against their preference, while IT and AVT antagonists had no significant effects. Then I asked if the establishment of privileged ties and the quality of association between cleaner wrasse pairs is correlated with neuroendocrine mechanisms involving forebrain neuropeptides and whether these neuropeptides level shifts relate to individual’s interspecific service quality. Here I found .that variation in pairs’ relationship influence male and female cleaner fish differently and contribute to the variation of brain neuropeptide levels, which is linked to distinct cooperative outcomes. Finally, I explore the link between these neuroendocrine pathways and the expression of mutualistic behaviour in fishes by comparing the brain quantitative distribution of AVT and IT across the overall and in selected areas of the brain; aiming at four closely related species of labrids that differ in the degree to which they depend on cleaning. The levels of both AVT and IT varied significantly across species, as measured in the whole brain or in specific macro-areas. More importantly, significantly higher AVT levels in cerebellum and in the whole brain were found in the obligate cleaner species, which seems to be related to expression of mutualistic behaviour. Overall, my study suggests that the neuropeptidergic system but mostly AVT pathways play a pivotal role in the regulation of interspecific cooperative behaviour and conspecific social behaviour among stabilized pairs of cleaner wrasses.
- Landscape genetics of a seagrass species in a tidal mudflat lagoonPublication . Berković, B.; Serrão, Ester; Alberto, FilipeIn this thesis I looked at different components of dispersal in the seagrass Zostera noltii, from the dispersal potential of both sexual and asexual propagules to indirect genetic estimation and landscape genetics analysis. My studies show that the dispersal biology of Z. noltii is very dependent on commonly underestimated asexual dispersal. This asexual LDD is the most parsimonious explanation for the wide distribution of clones in the lagoon and dramatically changes our view of the species’ life history. Furthermore, I propose that the observed lack of association between landscape features and spatial genetic structure is a consequence of this LDD of asexual propagules. The high dispersal capacity of Z. noltii combined with a tidal regime which homogenizes the otherwise complex lagoon habitat, are prevalent over any effects of landscape on gene flow caused by the lagoon complexity as shown by the landscape genetics analyses. Nevertheless, sexual reproduction also affects spatial genetic structure, as the positive kinship between clones within a 3 km range is a signature of restricted seed dispersal.
- Suplementos alimentares na menopausaPublication . Silva, Sofia Marina Fernandes da; Santos, Maria da Assunção Martinez Fernandez Macedo dosA chegada da menopausa marca o fim da fertilidade e o início de uma etapa com várias implicações biopsicossociais. As alterações hormonais evidentes na menopausa (hipoestrogenismo) estão associadas ao aparecimento de sintomas vasomotores, neuropsíquicos, disfunções sexuais, síndrome geniturinária da menopausa e distúrbios metabólicos, que podem degradar a qualidade de vida. Com o aumento da esperança média de vida, a mulher tende a menorizar estes efeitos desagradáveis, procurando mais e melhor saúde, uma vez que um terço da sua vida será passado nesta fase. A terapêutica hormonal de substituição é a mais eficaz no alívio destes sintomas, no entanto, dada a complexidade de riscos para a saúde e contraindicações, muitas mulheres optam hoje por terapias alternativas com recurso a suplementos alimentares. Com o crescimento exponencial a nível mundial dos suplementos alimentares, estes produtos têm vindo a assumir um lugar de destaque no quadro das novas lógicas de oferta e consumo de recursos terapêuticos, com a finalidade de aliviar e ajudar a prevenir o desconforto da menopausa. Esta dissertação tem o intuito de instruir a atividade farmacêutica no aconselhamento de suplementos alimentares na menopausa, combater a dispensa e o uso irracional dos mesmos e averiguar a veracidade dos seus benefícios no alívio dos sintomas da menopausa. Para tal, procedeu-se, numa primeira fase, ao levantamento dos suplementos alimentares indicados para a menopausa mais requisitados e vendidos em 2014 em oito farmácias comunitárias, nomeadamente Menopace® Plus, Estrofito® Forte, Estromineral® Serena Plus, Fisiogen®, Afron® Pleno, Climater® Plus, Estrosil® e o Menotril®, e, numa segunda fase, à análise das substâncias ativas presentes em cada um destes suplementos: vitaminas, minerais e plantas e extratos de ervas. Os suplementos alimentares analisados contêm substâncias com uma ampla variedade de propriedades farmacêuticas que parecem servir como uma alternativa razoável para a terapêutica hormonal de substituição para mulheres na menopausa e merece mais investigação e consideração.
- As transições dos alunos com necessidades educativas especiais do ensino secundário para o superiorPublication . Silva, Lara Filipa Loureiro e; Fragoso, AntónioA inclusão dos alunos com Necessidades Educativas Especiais (NEE) é uma temática que assume uma importância crucial em todos os níveis do sistema educativo, pelas implicações que esta pode trazer ao desenvolvimento dos alunos, por isso importa refletir e conhecer de que forma vai acontecendo essa inclusão, identificando as dificuldades que possam ocorrer na adaptação e na integração destes jovens. Através de uma investigação qualitativa pretendemos evidenciar a realidade dos estudantes de 1ºano com NEE na Universidade do Algarve, tendo como objetivos principais a caracterização dos sujeitos e a perceção que têm sobre o seu processo de inclusão na Universidade. Desta investigação fazem parte: seis estudantes com NEE e quatro docentes que lecionam a estes alunos. Os dados foram recolhidos através de entrevistas individuais e apontam para percursos diferenciados em função das problemáticas apresentadas e das perceções individuais das dificuldades e vivências experienciadas. Desta forma, refletimos sobre o modo como esta passagem para a universidade é trabalhada na perspetiva do aperfeiçoamento e aquisição de competências que possibilitem a estes jovens com NEE a adaptação plena na sociedade no futuro. Os resultados obtidos permitem caracterizar os estudantes NEE da Universidade do Algarve e sugerir um conjunto de recomendações com vista à melhoria da sua situação académica.
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