ESS - Escola Superior de Saúde
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- O orçamento da União Europeia - A problemática da sua insuficiênciaPublication . Curado, HenriqueO debate proposto - o orçamento da União Europeia vs a problemática da sua insuficiência - resulta da comparação das seguintes grandezas: o crescimento necessário para que a União Europeia se assumisse mais solidária , mais friendly dos problemas regionais e as perspectivas financeiras assumidas até 1999.
- Contributos da citologia analítica para estudos de biologia de levedurasPublication . Côrte-Real, Manuela; Sansonetty, Filipe; Ludovico, Paula; Fortuna, Margarida; Sousa, Maria João; Silva, Manuel Teixeira da; Leão, Cecília; Prudêncio, Cristina; Rodrigues, FernandoNeste artigo começamos por apresentar uma breve introdução à citologia analítica descrevendo alguns conceitos importantes desta disciplina bem como um dos instrumentos que a torna possível - o citómetro de fluxo. Referimos alguns dos aspectos relevantes desta instrumentação, em particular a possibilidade de medir a estrutura e o funcionamento de células vivas e de separar sub-populações celulares para posterior obtenção de culturas puras. Discutimos ainda os fundamentos de algumas aplicações e apresentamos os resultados obtidos nos nossos laboratórios com os seguintes estudos: i) efeitos de fungicidas no ciclo celular de leveduras; ii) relação entre a presença de proteínas de efluxo activas e a menor susceptibilidade de leveduras a antifúngicos; iii) avaliação de alterações estruturais e funcionais induzidas pelo ácido acético e sua relação com perda de viabilidade celular em populações de Saccharomyces cerevisiae e Zygosaccharomyces bailii; iv) determinação do potencial de membrana mitocondrial e avaliação da função mitocondrial de leveduras; v) determinação da ploidia de DNA em leveduras; vi) monitorização in vivo de processos celulares em S. cerevisiae e vii) morte celular programada induzida pelo ácido acético em S. cerevisiae. No decurso destes trabalhos, optimizámos diferentes protocolos de marcação celular recorrendo aos seguintes fl uorocromos: SYBR® Green I para a marcação de DNA; calceína-M, BCECF-AM, Rh123 e DiOC5 para a detecção de proteínas de efl uxo activo; DAF, FUN-1®, IP e Rh123 para a avaliação da integridade estrutural e funcional da célula; Rh123 para a avaliação de potencial de membrana mitocondrial, anexina V-FITC para a detecção de fosfatidilserina no folheto externo da membrana citoplasmática e FITC conjugado com dUTP (reacção de TUNEL) para a detecção de fragmentação internucleosomal de DNA.
- Rapid detection of efflux pumps and their relation with drug resistance in yeast cellsPublication . Prudêncio, Cristina; Sansonetty, Filipe; Sousa, Maria João; Côrte-Real, Manuela; Leão, Cecı́liaCell drug resistance can be due to the presence of active efflux pumps (AEP). Identification of yeast cells with a resistance phenotype is important either from a clinical, agricultural or biotechnological point of view. Rapid and reliable methods to detect AEP can be therefore very useful. Some yeast cells change their staining by cal-cein-AM, BCECF-AM, rhodamine 123 and DiOC5,when pretreated with verapamil, CCCP or ATP depletion, or when pretreated with specific antimicrobial agents. This fact may be interpreted as an indication of the presence/absence of AEP. Six yeast species were tested with a flowcytometric method (FCM) and an epifluorescence micro-scopic method (EFM), and ten other species were evalu-ated only by EFM. The minimum inhibitory concentration(MIC) of penconazol, benomyl and cycloheximide for Saccharomyces cerevisiae and Kluyveromyces marxia-nus, were determined by growth inhibition on solid me-dium and were compared to the staining changes de-tected by FCM. The FCM and the EFM allowed the detection of AEP in all the yeast species tested. High MIC values for adrug were related with the presence of at least one AEP indicated by the cytometric data. The FCM revealed to be a robust assay where as the EFM can be used as a preliminary test. It is possible to identify resistance/sensitivity patterns in yeast cells through cytometric detection methods of different efflux pumping systems.
- On transdisciplinarity in organizations, innovation and lawPublication . Caetano, João Relvão; Curado, Henrique; Jacquinet, MarcContemporaneous societies are facing complex economic problems, i.e. problems constituted by relationships of distinct types (managerial, technical, econmic, political, etc.), and those, in turn, are incorporatingvdeeply diverse elements wich are not foreign to the history of the various economic, political and legal systems.
- Harmful cyanobacterial toxic blooms in waste stabilization pondsPublication . Barros, Piedade; Martins, RosarioA coccoid picocyanobacterium Synechocystis sp. (0.6-2 µm of cell diameter) was found to be dominant during summer period in the experimental wastewater stabilisation pond of Marrakesh. The taxonomy of this isolated strain was confirmed by electron microscope study. The general patterns of ultrastructure and the mode of cell division resemble Chroococcales. The cyanobacterium strain was axenic and cultured on both inorganic Z8 and BG13 media. Mammalian toxicity was confirmed by mice bioassay. The major sympton of poisoning was severe diarrhoea. Histopathological study shows a slight hepatotoxicosis associated with a pronounced change in the intestinal mucosa which shows swelling and destruction of villi epithelium and shedding of enterocytes into the lumen. Although slow, these kinds of poisoning are comparable to those induced by okadiac acid intraperitoneal mice injection (diarrhetic shellfish poisoning “DSP” toxins). By using the enzyme-linked immunosorbent assay (ELISA), the amount of hepatotoxins “microcystins” was determined. The result shows that Synechocystis can produce a small amount of total microcystine [an average of 15 µg-1 dry weight corresponding to 20 ng(109cell)-1]. These findings lead us to consider Synechocystis as both a potent neurotoxin and hepatotoxin producer. Because of the confirmed cyanobacterium toxicity, an eventual ecological implication should be considered. However, a toxic chronic test experiment on Daphnia was simultaneously carried out. Juvenile D. magna (less than 24 hours old), were fed three concentrations (104 , 106 , 108 cells / ml) of Synechocystis. A group of organisms fed with Chlorella vulgaris (3. 105 cells/ml) and another group without food, were studied as control treatments. Only animals cultured with 104 cells/ml of cyanobacterium survived at 80% until the end of the test (21 days). Reproduction and normal growth occurred in control treatments fed with Chlorella vulgaris and the group fed with the lowest concentration of Synechocystis. One-way ANOVA statistical analyses show significant differences in Daphnia survival and growth, between treatments with and without Synechocystis and between treatments with and without food. In terms of this study, there is evidence that toxic picocyanobacteria blooms occurring in wastewater stabilization ponds of Marrakesh, could have harmful repercussions on zooplanktonic, bacteria and other algae communities. Consequently, this will constitute a possible hindrance for sewage self-purification process and system treatment performance. In addition, the reuse of such treated wastewater effluent for irrigation will constitute an additional, potent, health hazard for animals and human’s. Keywords Chlorella; daphnia; microcystins; picocyanobacteria; synechocystis; wastewater.
- Isolation, characterization and quantification of microcystins (heptapeptides hepatotoxins) in Microcystis aeruginosa dominated bloom of Lalla Takerkoust lake–reservoir (Morocco)Publication . Martins, RosarioThis paper presents the first data on the identification, characterization and quantification of microcystins isolated from both an extract of a cyanobacteria natural bloom, collected from a eutrophic Moroccan reservoir (Lalla Takerkoust, Marrakesh) and an isolated strain cultivated under laboratory conditions. The isolation and purification of toxins was performed by reverse phase HPLC and then characterized by amino acid analysis and fast atom bombardment mass spectrometry (FAB-MS). Chemical characterization of the toxins from the bloom revealed variants of microcystins such as Mcyst-LR, Mcyst-RR, Mcyst-YR and [D-Asp3]Mcyst-LR. However, the Microcystis aeruginosa strain produced only Mcyst-RR. Using an ELISA assay the total microcystin contents of eight bloom samples collected from 1994 to 1997 ranged from 0.7 to 8.8 μg/mg of lyophilized material. The two isolated Microcystis strains contained higher amounts of microcystins (0.65 μg/ mg of dry weight) than the Pseudanabaena strains (0.021 μg/mg of dry weight). Our results show that the presence of cyanobacteria toxins in water used for drinking in a North African country may be regarded as an health hazard. These results are a contribution to the knowledge of the biogeography of toxic cyanobacteria and their toxins, namely in north African countries.
- Isolation, excystation and axenization of Giardia lamblia isolates: in vitro susceptibility to metronidazole and albendazolePublication . Cruz, Agostinho; Sousa, M. Isaura; Azeredo, Zaida; Leite, Emilia; Sousa, J. C. Figueiredo de; Cabral, MiguelFrom 53 samples of human faeces containing Giardia lamblia cysts, 18 isolates were successfully excysted in vitro, and cultivated axenically in TYI-S-33 modified medium. The in vitro effects of metronidazole and albendazole on these isolates were evaluated by the trophozoite adherence inhibition method. The IC50 was between 2.4 and 11.5 µM for metronidazole and 0.027 and 0.192 µM for albendazole. These IC50 values were similar to those found for the ATCC 30888 and 30957 reference isolates. All isolates were susceptible to the antiparasitic drugs tested. These results suggest that resistance of G. lamblia to metronidazole and albendazole does not seem to be a significant problem in our population.
- In vitro metabolism of steroid hormones by ovary and hepatopancreas of the crustacean Penaeid shrimp Marsupenaeus japonicusPublication . Summavielle, Teresa; Monteiro, Pedro Ribeiro Rocha; Reis-Henriques, Maria Armanda; Coimbra, João; Monteiro, Pedro; Summavielle, TeresaRadioimmunoassay (RIA) was applied to identify selected metabolites obtained in in vitroincubations of ovarianand hepatopancreatic tissues from female Marsupenaeus japonicusin previtellogenic and vitellogenic maturation stages. Depend-ing on the precursors used, progesterone, 17α-hydroxyprogesterone or testosterone, it was possible to observe the presence of sev-eral enzymatic activities through metabolites detected in incubations. The present study provides evidence that the ovary of theshrimpM. japonicusis capable of synthesising 17β-estradiol from progesterone, evidencing the presence of 17α-hydroxy-lase, C17-C20lyase, 17β-hydroxysteroid dehydrogenase (17β-HSD) and aromatase. Enzymatic activities of aromatase, 3β-HSD and 17α-hydroxylase were detected in hepatopancreas, but not that of C17-C20lyase. These results suggest that 17β-estradiol could be the vitellogenesis stimulating ovarian hormone (VSOH), and together with former in vivoand in vitrostudies this leads us to propose that in fact there may be a physiological role for steroid hormones in the maturation cycleof crustaceans.
- Comparison between two common methods for measuring Giardia lamblia susceptibility to antiparasitic drugs in vitroPublication . Cruz, Agostinho; Sousa, M. Isaura; Azeredo, Zaida; Silva, M. Carolina; Sousa, J.C. Figueiredo de; Manso, Olga; Cabral, MiguelIn this study a comparison between two different methods for measuring the susceptibility of Giardia lamblia trophozoites to metronidazole and albendazole is performed. Modifications of Meloni’s method, based on the loss of adherence of parasites to surfaces, and the Hill method, based on the loss of parasite division capacity, are compared. A logistic model was used to calculate the inhibitory concentrations IC10, IC50 and IC90 that were further compared using the respective standard errors. The results obtained, after contact of parasites with the antiparasitic drugs for 24 h, show that the adherence method is more sensitive than the multiplication method for low and moderate inhibitory concentrations of albendazole. Conversely for metronidazole the multiplication method seems to be more sensitive for high inhibitory concentrations of the drug. For screening the IC50, both methods seem to be effective, however, the inhibition of adherence method have even better performance for the benzimidazole like drugs.
- Processo de auto-avaliação na Escola Superior de Tecnologia da Saúde (ESTSP): Um desafio enquadrado no espírito da Declaração de BolognaPublication . Fonte, Rosália; Prudêncio, CristinaAtendendo ao espírito da Declaração de Bologna, a livre circulação que determina a mobilidade de pessoas e a decorrente possibilidade de emprego nos países da U.E., pressupõe que sejam tomados em consideração conhecimentos, capacidades e competências, através do reconhecimento e validação dos diplomas obtidos nos países de origem. Para que tal aconteça é necessário que a qualidade dos diplomas seja garantida pelas Instituições de Ensino Superior (IES) através da Auto-Avaliação e pela Entidade que, a nível nacional, é responsável pelo sistema de qualidade, através da Avaliação externa (Andrade, 2003).