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- Comet assay assessment of oleic acid-coated magnetite nanoparticles on human SHSY5Y neuronal cellsPublication . Joao, Teixeira; Blanca, Laffon; Gözde, Kiliç; Natalia, Fernández-Bertólez; Carla, Costa; Solange, Costa; Eduardo, Passaro; Vanessa, ValdiglesiasSuperparamagnetic iron oxide nanoparticles (ION) have a wide range of potential applications. Among them, the most important uses in biology and medicine are as contrast agents in magnetic resonance imaging, as carriers for drug delivery or transfection and as therapeutic agents in cancer therapy by magnetic field-mediated hyperthermia. For all these applications, ION must be introduced in the human body and come into contact with cells and tissues, so it is imperative to know the potential risks associated to this exposure. Nevertheless, although ION biocompatibility has been reported to be high, there is a lack of information regarding their genotoxic potential, especially on the nervous system. Thus, the main objective of this work was to examine possible genotoxic effects of ION (crystalline phase magnetite, covered by oleic acid) on human SHSY5Y neuronal cells by the standard alkaline comet assay, along with its OGG1 enzyme modified version to analyse oxidative DNA damage. Previously we evaluated the possible interference of the ION with the comet assay methodology and with OGG1 enzyme activity. ION were dispersed both in complete and serum-free cell culture media, and cells were exposed to four concentrations in the range 10-200 µg/ml for 3 and 24 h. Results obtained showed increases in DNA damage, both primary and oxidative, after treatment with oleic acid-coated ION, even though the highest concentrations were found to interfere with OGG1 enzyme activity in incomplete cell culture medium. The results of this study encourage the need for checking the suitability of comet assay when used for testing genotoxicity of nanomaterials. Further investigations are required to assess the ability of ION to induce oxidative stress, and to elucidate the specific mechanism involved in primary DNA damage induced by these ION.
- Tinea capitis - retrospective analysis of cases diagnosed between 2004 and 2013Publication . Parada, Helena; Sabino, Raquel; Brandão, João; Furtado, Cristina; Veríssimo, CristinaTinea capitis is an infection of the hair and scalp caused by dermatophytes of the genera Trichophyton and Microsporum. Transmission may occur by person to person contact, or indirectly by contact with infected animals. The prevalence varies by country and region, being more prevalent in developing countries; children of are usually the most affected group.This study aims to describe the epidemiology of tinea capitis in the region of Lisbon and Tagus Valley, from January 2004 to December 2013.
- First description of food-borne Salmonella enterica resistance regions R1 and R3 associated with IS26 elementsPublication . Gomes-Neves, Eduarda; Manageiro, Vera; Ferreira, Eugénia; Correia da Costa, José M.; Caniça, ManuelaIn this study, we assessed the presence of IS26 in food-borne ASSuT-type Salmonella enterica isolates. A new genetic region (R3) was described, that included a C14 caspase gene between IS26 elements. R3 was present in two Salmonella Rissen isolates from a swine carcass and a meat handler, collected at the same abattoir. Furthermore, a new rearrangement of resistance region R1, harboring the blaTEM-1 gene flanked by IS26 elements, was identified in Salmonella Typhimurium and Salmonella 4,[5],12:i:-, from different samples. This study highlights the zoonotic potential of Salmonella spp. isolates and the possible role of IS26 in the mobilization of resistance genes.
- Current perspectives on the dynamics of antibiotic resistance in different reservoirsPublication . Caniça, Manuela; Manageiro, Vera; Jones-Dias, Daniela; Clemente, Lurdes; Gomes-Neves, Eduarda; Poeta, Patrícia; Dias, Elsa; Ferreira, EugéniaAntibiotic resistance consists of a dynamic web. In this review, we describe the path by which different antibiotic residues and antibiotic resistance genes disseminate among relevant reservoirs (human, animal, and environmental settings), evaluating how these events contribute to the current scenario of antibiotic resistance. The relationship between the spread of resistance and the contribution of different genetic elements and events is revisited, exploring examples of the processes by which successful mobile resistance genes spread across different niches. The importance of classic and next generation molecular approaches, as well as action plans and policies which might aid in the fight against antibiotic resistance, are also reviewed.
- Genetic basis of Familial Hypercholesterolemia in PortugalPublication . Bourbon, Mafalda; Aula no âmbito do mestrado em Biologia Humana e Ambiente, Faculdade de Ciências da Universidade de Lisboa, 2 julho 2015
- A novel insight on an ancient aromatic plant: The rosemary (Rosmarinus officinalis L.)Publication . Ribeiro-Santos, Regiane; Carvalho-Costa, Denise; Cavaleiro, Carlos; Costa, H.S.; Albuquerque, T.G.; Castilho, Maria Conceição; Ramos, Fernando; Melo, Nath ália R.; Sanches-Silva, AnaBackground: Rosemary (Rosmarinus officinalis L.) is a widely consumed aromatic plant that belongs to the Lamiaceae family. Fresh and dried leaves are frequently used in traditional Mediterranean cuisine and in folk medicine. Scope and approach: For this study, an extensive bibliographic review on rosemary was carried out, including its main uses, components (both nutrients and bioactive), biological activities, interactions with drugs and potential applications. Key findings and conclusions: The nutrient composition of rosemary reveals a great amount of vitamins and minerals. The most well studied bioactive compounds are carnosic acid, carnosol, caffeic acid and its derivative, rosmarinic acid. The levels on bioactive compounds depend on many factors, such as the variety, plant part, edafoclimatic conditions, drying conditions (if applied) and extraction and analysis methods. Numerous biological activities of rosemary are recognized including antioxidant, antibacterial and antifungal, anti-cancer, anti-inflammatory, among others. Therefore it has a vast range of industrial applications such as food and food packaging, pharmaceutical, perfumery and cosmetics industries.
- Molecular evidence of the close relatedness of clinical, gull and wastewater isolates of quinolone-resistant Escherichia coliPublication . Varela, Ana Rita; Manageiro, Vera; Ferreira, Eugénia; Guimarães, M. Augusta; da Costa, Paulo Martins; Caniça, Manuela; Manaia, Célia M.Escherichia coli with reduced susceptibility to quinolones isolated from different environmental sources (urban wastewater treatment plants, n = 61; hospital effluent, n = 10; urban streams, n = 9; gulls, n = 18; birds of prey, n = 17) and from hospitalised patients (n = 28) were compared based on multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). The habitats with the most diversified genotypes of quinolone-resistant E. coli, corresponding to the highest genetic diversity (H′), were wastewater and gulls. In addition, genetically distinct populations were observed in clinical samples and birds of prey, suggesting the influence of the habitat or selective pressures on quinolone-resistant E. coli. The close genetic relatedness between isolates of clinical origin and from gulls and wastewater suggests the existence of potential routes of propagation between these sources. The most common sequence types were ST131 and ST10, with ST131 being highly specific to patients, although distributed in all of the other habitats except birds of prey. The prevalence of antimicrobial resistance was significantly higher in isolates from patients and gulls than from other sources (P < 0.01), suggesting that the effect of selective pressures met by isolates subjected to strong human impacts. The evidence presented suggests the potential circulation of bacteria between the environmental and clinical compartments, with gulls being a relevant vector of bacteria and resistance genes.
- Interações embalagem alimento e segurança alimentar- 2014/2015Publication . Sanches-Silva, Ana
- Capsular typing of Streptococcus pneumoniae isolated in an Algerian hospital using a new multiplex PCR-based schemePublication . Ziane, Hanifa; Manageiro, Vera; Ferreira, Eugénia; Bektache, Soumia; Tazir, Mohamed; Caniça, ManuelaWe developed a new sequential multiplex-PCR-based typing scheme (MPBTS) for pneumococcal capsular classification. The serogroup/type of 37 control isolates obtained by the Quellung reaction, MPBTS, and nucleotide sequencing, were fully concordant. The serogroups/types of 75 invasive isolates determined by MPBTS, presented 100% specificity and 96% sensitivity, when compared with the Quellung reaction.
- Complete Sequence of a blaOXA-48-Harboring IncL Plasmid from an Enterobacter cloacae Clinical IsolatePublication . Manageiro, Vera; Pinto, Margarida; Caniça, ManuelaWe report a 63,584-bp conjugative IncL plasmid (pUR17313-1) from an Enterobacter cloacae clinical isolate, containing a blaOXA-48 gene. The plasmid sequence also carried important mobile genetic elements involved in the spread of antibiotic resistance, namely, the Tn1999.2 composite transposon, which enclosed blaOXA-48-, integrase-, and transposase-encoding genes.