ESS - CM - Ciências Morfológicas
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- Alterações anatómicas induzidas pela idade na coluna vertebral: intervenção para melhoria da saúde da comunidadePublication . Ribas, Jorge; Ribas, C.; Prudêncio, CristinaO aumento do envelhecimento da população implica uma crescente importância na implementação da política de cuidados de saúde primários. O envelhecimento leva a profundas alterações na morfologia da coluna vertebral do indivíduo. Estas alterações não estão ainda devidamente caracterizadas pelo que é necessário estudar e tipificar quais as mudanças induzidas pela idade. Desta forma será possível avaliar de que forma o patológico se poderá enquadrar num padrão normal de envelhecimento.
- Promoção da saúde da mulher com incontinência urinária: validação de instrumentos de avaliaçãoPublication . Ribas, C.; Ribas, Jorge; Prudêncio, CristinaA incontinência urinária (IU) feminina é um importante problema de saúde pública, quer pela sua prevalência, quer pelo elevado impacto físico, psíquico e social na vida da doente. Embora a prevalência da IU tenha sido descrita em vários trabalhos como mais elevada em mulheres idosas, esta perturbação atinge igualmente mulheres jovens e de meia-idade ou seja no ciclo da vida activa. Desta forma constitui um handicap na condição da mulher quer ao nível profissional, familiar e/ou sexual.
- Toxicity assessment of crude and partially purified extracts of marine Synechocystis and Synechococcus cyanobacterial strains in marine invertebratesPublication . Martins, Rosario; Fernandez, Nuria; Beiras, Ricardo; Vasconcelos, VítorAmong the Cyanoprokaryota, the genera Synechocystis and Synechococcus have rarely been studied with respect to potential toxicity. This is particularly true with marine environments where studies about the toxicity of cyanobacteria are restricted to filamentous forms at the warmer temperate and tropical regions and also to filamentous forms at cold seas such as the Baltic Sea. In this study, we describe the effects of cyanobacterial strains of the Synechocystis and Synechococcus genera isolated from the marine coast of Portugal, on marine invertebrates. Crude and partially purified extracts at a concentration of 100 mg/ml of freeze-dried material of the marine strains were tested for acute toxicity in nauplii of the brine shrimp Artemia salina, in the rotifer Brachionus plicatillis and in embryos of the sea urchin Paracentrotus lividus and the mussel Mytilus galloprovincialis. The cyanobacterial extracts, especially the crude extract, had an impact on A. salina nauplii. No significant toxic effects were registered against the rotifer. A negative impact of all strains was recorded on the embryonic development of the sea urchin, with toxic effects resulting in an inhibition of embryogenesis or development of smaller larvae. To the mussel embryos, the effects of cyanobacterial extracts resulted in a complete inhibition of embryogenesis. The results of all assays indicate that Synechocystis and Synechococcus marine strains contained toxic compounds to marine invertebrates.
- Antimicrobial and cytotoxic assessment of marine cyanobacteria - synechocystis and synechococcusPublication . Martins, Rosario; Ramos, Miguel; Herfindal, Lars; Sousa, José; Skærven, Kaja; Vasconcelos, VítorAqueous extracts and organic solvent extracts of isolated marine cyanobacteria strains were tested for antimicrobial activity against a fungus, Gram-positive and Gram-negative bacteria and for cytotoxic activity against primary rat hepatocytes and HL-60 cells. Antimicrobial activity was based on the agar diffusion assay. Cytotoxic activity was measured by apoptotic cell death scored by cell surface evaluation and nuclear morphology. A high percentage of apoptotic cells were observed for HL-60 cells when treated with cyanobacterial organic extracts. Slight apoptotic effects were observed in primary rat hepatocytes when exposed to aqueous cyanobacterial extracts. Nine cyanobacteria strains were found to have antibiotic activity against two Gram-positive bacteria, Clavibacter michiganensis subsp. insidiosum and Cellulomonas uda. No inhibitory effects were found against the fungus Candida albicans and Gram-negative bacteria. Marine Synechocystis and Synechococcus extracts induce apoptosis in eukaryotic cells and cause inhibition of Gram-positive bacteria. The different activity in different extracts suggests different compounds with different polarities.
- A avaliação de stress em saúde ocupacional numa equipa de urgência: um estudo pilotoPublication . Ribas, Cláudia; Ribas, Jorge; Abreu, Sofia; Fonte, Rosália; Moucho, Marina; Montenegro, Nuno; Prudêncio, CristinaO presente estudo constituiu um estudo preliminar que se debruçou sobre a avaliação do stress em Saúde Ocupacional em profissionais que integram o serviço de urgência de Obstétrica do Hospital de S. João no Porto. Esta avaliação visa a elaboração de estratégias que contribuam para a maximização dos cuidados de saúde e está diretamente associada à tríada recursos humanos, materiais e satisfação do utente.
- Hábitos e comportamentos associados ao uso de antibióticos: A autonomia individual versus a saúde da comunidadePublication . Prudêncio, Cristina; Ferraz, Ricardo; Vieira, Mónica; Ribas, Cláudia; Ribas, Jorge; Fonte, Rosália; Fernandes, RubenA resistência a drogas é um dos graves problemas de saúde atual embora possa ser considerada uma resposta natural devida à pressão seletiva da droga. Esta resposta é no entanto exacerbada por vários fatores que incluem, abuso, subutilização ou má utilização, má adesão ao tratamento ou má qualidade das drogas disponíveis. Trata-se de um dos maiores desafios que enfrentam atualmente os profissionais de Saúde e a população em geral. A auto-medicação é um dos fatores que mais contribui para a resistência a antibióticos. No presente trabalho apresentamos um estudo preliminar onde foram avaliados os hábitos e comportamentos associados ao uso de antibióticos num grupo de Pais.
- Primary screening of the bioactivity of brackishwater cyanobacteria: toxicity of crude extracts to artemia salina larvae and paracentrotus lividus embryosPublication . Lopes, Viviana; Fernandez, Nuria; Martins, Rosario; Vasconcelos, VítorCyanobacteria are a diverse group of Gram-negative bacteria that produce an array of secondary compounds with selective bioactivity against vertebrates, invertebrates, plants, microalgae, fungi, bacteria, viruses and cell lines. The aim of this study was to assess the toxic effects of aqueous, methanolic and hexane crude extracts of benthic and picoplanktonic cyanobacteria isolated from estuarine environments, towards the nauplii of the brine shrimp Artemia salina and embryos of the sea urchin Paracentrotus lividus. The A. salina lethality test was used as a frontline screen and then complemented by the more specific sea urchin embryo-larval assay. Eighteen cyanobacterial isolates, belonging to the genera Cyanobium, Leptolyngbya, Microcoleus, Phormidium, Nodularia, Nostoc and Synechocystis, were tested. Aqueous extracts of cyanobacteria strains showed potent toxicity against A. salina, whereas in P. lividus, methanolic and aqueous extracts showed embryo toxicity, with clear effects on development during early stages. The results suggest that the brackishwater cyanobacteria are producers of bioactive compounds with toxicological effects that may interfere with the dynamics of invertebrate populations.
- Morphological, toxicological and molecular characterization of a benthic Nodularia isolated from Atlantic estuarine environmentsPublication . Lopes, Viviana R.; Antunes, Agostinho; Welker, Martin; Martins, Rosário; Vasconcelos, Vítor M.A polyphasic study of a benthic Nodularia isolate (LEGE06071) from an Atlantic environment, specifically salt pans, was performed. LEGE06071 resembled both type strains of Nodularia sphaerocarpa and Nodularia harveyana, while ACOI00729 (purchased isolate) was identified as N. sphaerocarpa. The length and width of vegetative cells varied from 3.10 to 3.15 mu m and from 3.71 to 4.25 mu m, respectively, while heterocyts were 3.91-4.89 mu m long and 4.20-4.74 mu m, wide. None of the isolates had aerotopes. The sequencing of the 16S rRNA gene from the two Nodularia isolates indicated that they belonged neither to Nodularia spumigena nor N. harveyana. Nodularin and other cyanotoxin synthesis-associated genes could not be detected, nor could nodularin production be detected by ELISA. However, MALDI-TOF analysis of LEGE06071 revealed the presence of other compounds, namely, glycolipids. Hence, toxicological screenings against Artemia nauplii, Escherichia coli and Salmonella typhimurium were performed. Toxic effects could only be observed against Artemia, with 48 h-LC50 values for the aqueous and crude extract of methanol of 53.21 mg ml(-1) and 17.81 mg ml(-1), respectively. This study presents the first evidence of a non-nodularin-producing Nodularia isolate in Atlantic salt pan ecosystems and its potential ecotoxicity against Artemia sp. (C) 2009 Elsevier Masson SAS. All rights reserved.
- Are known cyanotoxins involved in the toxicity of picoplanktonic and filamentous north atlantic marine cyanobacteria?Publication . Frazão, Bárbara; Martins, Rosario; Vasconcelos, VítorEight marine cyanobacteria strains of the genera Cyanobium, Leptolyngbya, Oscillatoria, Phormidium, and Synechococcus were isolated from rocky beaches along the Atlantic Portuguese central coast and tested for ecotoxicity. Strains were identified by morphological characteristics and by the amplification and sequentiation of the 16S rDNA. Bioactivity of dichloromethane, methanol and aqueous extracts was assessed by the Artemia salina bioassay. Peptide toxin production was screened by matrix assisted laser desorption/ionization time of flight mass spectrometry. Molecular analysis of the genes involved in the production of known cyanotoxins such as microcystins, nodularins and cylindrospermopsin was also performed. Strains were toxic to the brine shrimp A. salina nauplii with aqueous extracts being more toxic than the organic ones. Although mass spectrometry analysis did not reveal the production of microcystins or other known toxic peptides, a positive result for the presence of mcyE gene was found in one Leptolyngbya strain and one Oscillatoria strain. The extensive brine shrimp mortality points to the involvement of other unknown toxins, and the presence of a fragment of genes involved in the cyanotoxin production highlight the potential risk of cyanobacteria occurrence on the Atlantic coast.
- Cytotoxicity in L929 fibroblasts and inhibition of herpes simplex virus type 1 Kupka by estuarine cyanobacteria extractsPublication . Lopes, Viviana R.; Schmidtke, Michaela; Fernandes, Maria Helena; Martins, Rosario; Vasconcelos, VítorThe cyanobacteria are known to be a rich source of metabolites with a variety of biological activities in different biological systems. In the present work, the bioactivity of aqueous and organic (methanolic and hexane) crude extracts of cyanobacteria isolated from estuarine ecosystems was studied using different bioassays. The assessment of DNA damage on the SOS gene repair region of mutant PQ37 strain of Escherichia coli was performed. Antiviral activity was evaluated against influenza virus, HRV-2, CVB3 and HSV-1 viruses using crystal violet dye uptake on HeLa, MDCK and GMK cell lines. Cytotoxicity evaluation was performed with L929 fibroblasts by MTT assay. Of a total of 18 cyanobacterial isolates studied, only the crude methanolic extract of LEGE 06078 proved to be genotoxic (IF > 1.5) in a dose-dependent manner and other four were putative candidates to induce DNA damage. Furthermore, the crude aqueous extract of LEGE 07085 showed anti- herpes type 1 activity (IC50 = 174.10 μg dry extract mL−1) while not presenting any cytotoxic activity against GMK cell lines. Of the 54 cyanobacterial extracts tested, only the crude methanolic and hexane ones showed impair on metabolic activity of L929 fibroblasts after long exposure (48–72 h). The inhibition of HSV-1 and the strong cytotoxicity against L929 cells observed emphasizes the importance of evaluating the impact of those estuarine cyanobacteria on aquatic ecosystem and on human health. The data also point out their potential application in HSV-1 treatment and pharmacological interest.