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- Is there sufficient training of health care staff on noise reduction in neonatal intensive care units? A pilot study from neonoise projectPublication . Alberto Alves Carvalhais, Carlos; Santos, Joana; Vieira Da Silva, Manuela; Xavier, AnaEvidence indicates that exposure to high levels of noise adversely affects human health, and these effects are dependent upon various factors. In hospitals, there are many sources of noise, and high levels exert an impact on patients and staff, increasing both recovery time and stress, respectively. The goal of this pilot study was to develop, implement, and evaluate the effectiveness of a training program (TP) on noise reduction in a neonatal intensive care unit (NICU) by comparing the noise levels before and after the implementation of the program. In total, 79 health professionals participated in the study. The measurements of sound pressure levels took into account the layout of the unit and locations of the main sources of noise.
- Human salivary α-amylase (EC.3.2.1.1) activity and periodic acid and schiff reactive (PAS) staining: a useful tool to study polysaccharides at an undergraduate levelPublication . Fernandes, Ruben; Correia, Rossana; Fonte, Rosália; Prudêncio, CristinaHealth science education is presently in discussion throughout Europe due to the Bologna Declaration. Teaching basic sciences such as biochemistry in a health sciences context, namely in allied heath education, can be a challenging task since the students of preclinical health sciences are not often convinced that basic sciences are clinically valuable (J. R. Rudland, S. C. Rennie ( 2003) The determination of the relevance of basic sciences learning objectives to clinical practice using a questionnaire survey, Med. Educ. (Oxf.) 37, 962-965; E. C. Wragg ( 2003) How can we determine the relevance of basic sciences learning objectives to clinical practice?, Med. Educ. ( Oxf.) 37, 948-949). Thus, nowadays teachers are compelled to use their imagination to be able to elaborate laboratory sessions aiming for the understanding of theoretical concepts that are also clinically related: in other words, basic concepts and skills that underlie the competencies demanded of the future health professional. In the present work, we describe a set of laboratory sessions implemented in the discipline of biochemistry, belonging to the first year of several courses of allied health professionals, which can also be implemented in other health sciences courses. These sessions focus on the characteristics and properties of carbohydrates. The exercises we propose include two different laboratory practical sessions based on a histopathological routine technique known as periodic acid and Schiff reactive that is currently used to detect sugar metabolic and tumor diseases ( J. M. T. Rivera, C. T. Lopez, B. C. Segui ( 2001) Bioquimica Estructural: Conceptos y Tests, Tebar Flores, Madrid). The methodology described enables the demonstration of some biochemical properties of polysaccharides, namely animal and vegetable, and the catalytic activity of the human salivary alpha-amylase (EC.3.2.1.1) enzyme. A further comparison between alpha-amylase activity in vitro and in situ is also possible by the proposed methodology. Additionally, to this extent, a comparison between the results of the learning improvement that occurred after the implementation of this tool is presented.
- Avaliação da exposição ocupacional a vibrações transmitidas ao sistema corpo inteiro: estudo preliminar em motoristas de pesados de mercadoriasPublication . Costa, Sofia; Santos, Joana; Silva, Maria V.; Neves, PaulaAs vibrações transmitidas ao corpo inteiro (VCI) são um agente físico que afecta os condutores de camiões e apresenta consequências para a sua saúde, estando fortemente associada à dor lombar. No presente estudo seleccionou-se um motorista que conduz um veículo pesado de mercadorias com classificação N3 e que efectua rotas de pequeno curso no Norte de Portugal. As medições realizaram-se em dois dias representativos da actividade semanal, em duas rotas distintas (Rota 1 e 2), de acordo com a metodologia definida no Decreto-Lei n.º 46/2006 de 24 de Fevereiro e na NP ISO 2631-1 de 2007. Foi utilizado um analisador de vibrações, sendo o acelerómetro triaxial fixado ao assento do veículo, de forma a quantificar a aceleração eficaz nos três eixos ortogonais x, y e z. Complementarmente ao processo de amostragem, aplicou-se um questionário a sete motoristas. Os resultados demonstram a dominância da direcção vertical (z) com picos de aceleração na frequência de 1,6Hz. A degradação do piso e a ausência de carga do veículo foram identificados como factores responsáveis pelo aumento dos níveis vibracionais. Relativamente à exposição do trabalhador, obteve-se valores de A(8) Rota 1 de 0,22 m/s2 e A(8) Rota 2 de 0,14 m/s2, sendo o A(8) semanal de 0,19 m/s2, verificando-se que os valores obtidos são inferiores ao valor de acção de exposição preconizado na legislação nacional (0,5m/s2). Quanto aos sintomas manifestados pelos motoristas destacam-se: dor lombar (43%), fadiga (71%), irritabilidade (57%) e dores de cabeça (57%). Apesar dos valores obtidos evidenciarem que o trabalhador não se encontra exposto, segundo o preconizados na legislação, devem ser implementadas medidas que visem a manutenção e conservação dos pisos das vias, manutenção dos veículos e elaboração de planos de formação que abordem o tipo de condução e as posturas a adoptar para salvaguarda do bem-estar e conforto dos trabalhadores.
- Lichens as bio indicators of atmospheric pollution in Porto, PortugalPublication . Freitas, Marisa; Costa, Natália; Rodrigues, Matilde; Marques, Joana; Vieira Da Silva, ManuelaThe emission of air pollutants mainly from anthropogenic sources has led to the degradation of air quality. These pollutants determine the occurrence or worsening of respiratory disorders. Biomonitoring provides information on the quality of the environment or its modifications, having been used as an alternative to monitoring of chemical pollutants. The variation of the biodiversity of lichens can be used as a warning to check if other biological systems are being affected by atmospheric pollution. Lichens have been used as bioindicators, since they have differential sensitivity to air pollution. The purpose of this study was to assess the diversity and abundance of lichens in different zones of the Porto (North Portugal) with respect to the rates of atmospheric pollutants. Three zones were selected for sampling, represented by urban, suburban and rural zones. LDV was calculated for each zone. The average concentrations of CO, CO2, SO2, NO2, O3 and PM10 were also measured. The most sensitive lichens were present in the area with the highest LDV. In places where there were higher concentrations of pollutants, namely NO2 and SO2 a lower LDV. This study suggests that lichens can be used as prevention systems to protect public health, in particular diseases related to air pollution and as a potential alternative or complement to expensive chemical monitoring equipment.
- Application of real-time PCR in the assessment of the toxic cyanobacterium cylindrospermopsis raciborskii abundance and toxicological potentialPublication . Moreira, Cristiana; Martins, António; Azevedo, Joana; Freitas, Marisa; Regueiras, Ana; Vale, Micaela; Antunes, Agostinho; Vasconcelos, VítorCyanobacteria are prokaryotic photosynthetic microorganisms that pose a serious threat to aquatic environments because they are able to form blooms under eutrophic conditions and produce toxins. Cylindrospermopsis raciborskii is a planktonic heterocystous filamentous cyanobacterium initially assigned to the tropics but currently being found in more temperate regions such as Portugal, the southernmost record for this species in Europe. Cylindrospermopsin originally isolated from C. raciborskii is a cytotoxic alkaloid that affects the liver, kidney, and other organs. It has a great environmental impact associated with cattle mortality and human morbidity. Aiming in monitoring this cyanobacterium and its related toxin, a shallow pond located in the littoral center of Portugal, Vela Lake, used for agriculture and recreational purposes was monitored for a 2-year period. To accomplish this, we used the real-time PCR methodology in field samples to quantify the variation of specific genetic markers with primers previously described characterizing total cyanobacteria (16S rRNA), C. raciborskii (rpoC1), and cylindrospermopsin synthetase gene (pks). The results report the high abundance of both cyanobacteria and C. raciborskii in Vela Lake, with C. raciborskii representing 0.4% to 58% of the total cyanobacteria population. Cylindrospermopsin synthetase gene was detected in one of the samples. We believe that with the approach developed in this study, it will be possible to monitor C. raciborskii population dynamics and seasonal variation, as well as the potential toxin production in other aquatic environments.
- Seasonal dynamics of microcystis spp. and their toxigenicity as assessed by qPCR in a temperate reservoirPublication . Martins, António; Moreira, Cristiana; Vale, Micaela; Freitas, Marisa; Regueiras, Ana; Antunes, Agostinho; Vasconcelos, VítorBlooms of toxic cyanobacteria are becoming increasingly frequent, mainly due to water quality degradation. This work applied qPCR as a tool for early warning of microcystin(MC)-producer cyanobacteria and risk assessment of water supplies. Specific marker genes for cyanobacteria, Microcystis and MC-producing Microcystis, were quantified to determine the genotypic composition of the natural Microcystis population. Correlations between limnological parameters, pH, water temperature, dissolved oxygen and conductivity and MC concentrations as well as Microcystis abundance were assessed. A negative significant correlation was observed between toxic (with mcy genes) to non-toxic (without mcy genes) genotypes ratio and the overall Microcystis density. The highest proportions of toxic Microcystis genotypes were found 4-6 weeks before and 8-10 weeks after the peak of the bloom, with the lowest being observed at its peak. These results suggest positive selection of non-toxic genotypes under favorable environmental growth conditions. Significant positive correlations could be found between quantity of toxic genotypes and MC concentration, suggesting that the method applied can be useful to predict potential MC toxicity risk. No significant correlation was found between the limnological parameters measured and MC concentrations or toxic genotypes proportions indicating that other abiotic and biotic factors should be governing MC production and toxic genotypes dynamics. The qPCR method here applied is useful to rapidly estimate the potential toxicity of environmental samples and so, it may contribute to the more efficient management of water use in eutrophic systems.
- Stability of the transthyretin molecule as a key factor in the interaction with a-beta peptide--relevance in Alzheimer's diseasePublication . Ribeiro, Carlos A.; Saraiva, Maria João; Cardoso, IsabelTransthyretin (TTR) protects against A-Beta toxicity by binding the peptide thus inhibiting its aggregation. Previous work showed different TTR mutations interact differently with A-Beta, with increasing affinities correlating with decreasing amyloidogenecity of the TTR mutant; this did not impact on the levels of inhibition of A-Beta aggregation, as assessed by transmission electron microscopy. Our work aimed at probing differences in binding to A-Beta by WT, T119M and L55P TTR using quantitative assays, and at identifying factors affecting this interaction. We addressed the impact of such factors in TTR ability to degrade A-Beta. Using a dot blot approach with the anti-oligomeric antibody A11, we showed that A-Beta formed oligomers transiently, indicating aggregation and fibril formation, whereas in the presence of WT and T119M TTR the oligomers persisted longer, indicative that these variants avoided further aggregation into fibrils. In contrast, L55PTTR was not able to inhibit oligomerization or to prevent evolution to aggregates and fibrils. Furthermore, apoptosis assessment showed WT and T119M TTR were able to protect against A-Beta toxicity. Because the amyloidogenic potential of TTR is inversely correlated with its stability, the use of drugs able to stabilize TTR tetrameric fold could result in increased TTR/ABeta binding. Here we showed that iododiflunisal, 3-dinitrophenol, resveratrol, [2-(3,5-dichlorophenyl)amino] (DCPA) and [4- (3,5-difluorophenyl)] (DFPB) were able to increase TTR binding to A-Beta; however only DCPA and DFPB improved TTR proteolytic activity. Thyroxine, a TTR ligand, did not influence TTR/A-Beta interaction and A-Beta degradation by TTR, whereas RBP, another TTR ligand, not only obstructed the interaction but also inhibited TTR proteolytic activity. Our results showed differences between WT and T119M TTR, and L55PTTR mutant regarding their interaction with A-Beta and prompt the stability of TTR as a key factor in this interaction, which may be relevant in AD pathogenesis and for the design of therapeutic TTR-based therapies.
- Predictive Biomarkers of Bacillus Calmette-Gu´erin Immunotherapy Response in Bladder Cancer: Where AreWe Now?Publication . Lima, Luís; Dinis-Ribeiro, Mário; Longatto-Filho, Adhemar; Santos, LúcioThe most effective therapeutic option for managing nonmuscle invasive bladder cancer (NMIBC), over the last 30 years, consists of intravesical instillations with the attenuated strain Bacillus Calmette-Gu´erin (the BCG vaccine). This has been performed as an adjuvant therapeutic to transurethral resection of bladder tumour (TURBT) and mostly directed towards patients with highgrade tumours, T1 tumours, and in situ carcinomas. However, from 20% to 40% of the patients do not respond and frequently present tumour progression. Since BCG effectiveness is unpredictable, it is important to find consistent biomarkers that can aid either in the prediction of the outcome and/or side effects development. Accordingly, we conducted a systematic critical review to identify themost preeminent predictive molecular markers associated with BCG response. To the best of our knowledge, this is the first review exclusively focusing on predictive biomarkers for BCG treatment outcome. Using a specific query, 1324 abstracts were gathered, then inclusion/exclusion criteria were applied, and finally 87 manuscripts were included. Several molecules, including CD68 and genetic polymorphisms, have been identified as promising surrogate biomarkers. Combinatory analysis of the candidate predictive markers is a crucial step to create a predictive profile of treatment response.
- Culture-dependent characterization of cyanobacterial diversity in the intertidal zones of the Portuguese coast: A polyphasic studyPublication . Brito, Ângela; Ramos, Vitor; Seabra, Rui; Santos, Arlete; Santos, Catarina; Lopo, Miguel; Ferreira, Sérgio; Martins, António; Mota, Rita; Frazão, Bárbara; Martins, Rosario; Vasconcelos, Vítor; Tamagnini, PaulaCyanobacteria are important primary producers, and many are able to fix atmospheric nitrogen playing a key role in the marine environment. However, not much is known about the diversity of cyanobacteria in Portuguese marine waters. This paper describes the diversity of 60 strains isolated from benthic habitats in 9 sites (intertidal zones) on the Portuguese South and West coasts. The strains were characterized by a morphological study (light and electron microscopy) and by a molecular characterization (partial 16S rRNA, nifH, nifK, mcyA, mcyE/ndaF, sxtI genes). The morphological analyses revealed 35 morphotypes (15 genera and 16 species) belonging to 4 cyanobacterial Orders/Subsections. The dominant groups among the isolates were the Oscillatoriales. There is a broad congruence between morphological and molecular assignments. The 16S rRNA gene sequences of 9 strains have less than 97% similarity compared to the sequences in the databases, revealing novel cyanobacterial diversity. Phylogenetic analysis, based on partial 16S rRNA gene sequences showed at least 12 clusters. One-third of the isolates are potential N2-fixers, as they exhibit heterocysts or the presence of nif genes was demonstrated by PCR. Additionally, no conventional freshwater toxins genes were detected by PCR screening.
- Rapid Evolution of the Sequences and Gene Repertoires of Secreted Proteins in BacteriaPublication . Nogueira, Teresa; Touchon, Marie; Rocha, Eduardo P. C.Proteins secreted to the extracellular environment or to the periphery of the cell envelope, the secretome, play essential roles in foraging, antagonistic and mutualistic interactions. We hypothesize that arms races, genetic conflicts and varying selective pressures should lead to the rapid change of sequences and gene repertoires of the secretome. The analysis of 42 bacterial pan-genomes shows that secreted, and especially extracellular proteins, are predominantly encoded in the accessory genome, i.e. among genes not ubiquitous within the clade. Genes encoding outer membrane proteins might engage more frequently in intra-chromosomal gene conversion because they are more often in multi-genic families. The gene sequences encoding the secretome evolve faster than the rest of the genome and in particular at non-synonymous positions. Cell wall proteins in Firmicutes evolve particularly fast when compared with outer membrane proteins of Proteobacteria. Virulence factors are over-represented in the secretome, notably in outer membrane proteins, but cell localization explains more of the variance in substitution rates and gene repertoires than sequence homology to known virulence factors. Accordingly, the repertoires and sequences of the genes encoding the secretome change fast in the clades of obligatory and facultative pathogens and also in the clades of mutualists and free-living bacteria. Our study shows that cell localization shapes genome evolution. In agreement with our hypothesis, the repertoires and the sequences of genes encoding secreted proteins evolve fast. The particularly rapid change of extracellular proteins suggests that these public goods are key players in bacterial adaptation.