Rui Miguel Magalhães

• BSc
• PhD at Universidade Católica Portuguesa

Listeria monocytogenes is a foodborne pathogen that causes listeriosis in humans, the severity of which depends on multiple factors, including intrinsic characteristics of the affected individuals and the pathogen itself. Additionally, emerging evidence suggests that epigenetic modifications may also modulate host susceptibility to infection. There...

A newly produced silk fibroin (SF) aerogel particulate system using a supercritical carbon dioxide (scCO2)-assisted drying technology is herein proposed for biomedical applications. Different concentrations of silk fibroin (3%, 5%, and 7% (w/v)) were explored to investigate the potential of this technology to produce size- and porosity-controlled p...

Listeria monocytogenes is a ubiquitous microorganism responsible for listeriosis, a severe disease in humans that become infected by ingesting contaminated foods. Although it can occur in healthy humans, listeriosis affects mainly the elderly, immuno-compromised, pregnant women and newborns, with a high case fatality rate (20%–30%). This article wi...

Calcium plays an important role in barrier function repair and skin homeostasis. In particular, calcium phosphates (CaPs) are well established materials for biomedical engineering due to their biocompatibility. To generate biomaterials with a more complete set of biological properties, previously discarded silk sericin (SS) has been recovered and u...

Water contaminated with microbiological and chemical constituents can cause a variety of diseases. Water bodies may become contaminated by wild and domestic animal feces, agricultural runoff or sewage, and are often overlooked as a reservoir and source of human infection by pathogenic microorganisms. The objectives of this study were to evaluate th...

Epidemiological studies show that improper food handling practices at home account for a significant portion of foodborne illness cases. Mishandling of raw meat during meal preparation is one of the most frequent hazardous behaviours reported in observational research studies that potentially contributes to illness occurrence, particularly through...

Peripheral nerve injury remains a clinical challenge with severe physiological and functional consequences. Despite the existence of multiple possible therapeutic approaches, until now, there is no consensus regarding the advantages of each option or the best methodology in promoting nerve regeneration. Regenerative medicine is a promise to overcom...

Conventional methods for the detection of Listeria monocytogenes in foods and environmental samples rely on selective pre-enrichment, enrichment, and plating. This is followed by confirmation of suspected colonies by testing a limited number of biochemical markers.

Volatile phenols in wines are responsible for unpleasant aromas, which negatively affect the quality of the wine. These compounds are produced from the metabolism of hydroxycinnamic acids, mainly by the yeasts Brettanomyces/Dekkera. Relevant data, potentially useful to support decisions on how to manage the risk of contamination of wines by Brettan...

It was developed a material to act as an antimicrobial and antiparasitic agent through a modification reaction in the gum structure extracted from the plant Sterculia striata. This material was characterized, the oxidant activity was evaluated and the antimicrobial activity against Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Salmone...

The aim of this study was to conduct a preliminary investigation on the occurrence of Salmonella spp. in eggs from chickens raised in backyards in Portugal and Romania. A lack of compliance with safety practices by chicken owners, was demonstrated, especially in Portugal, as 96% of the eggs were visibly dirty and 92.5% were stored at room temperatu...

Stem/stromal cell-based therapies are a branch of regenerative medicine and stand as an attractive option to promote the repair of damaged or dysfunctional tissues and organs. Olfactory mucosa mesenchymal stem/stromal cells have been regarded as a promising tool in regenerative therapies because of their several favorable properties such as multipo...

The objective of this work was to investigate the effect of stress conditions frequently encountered in food- associated environments on virulence-associated characteristics of eight strains of Listeria monocytogenes. Strains were grown at low (11 °C, cold stress) and optimal (37 °C) temperatures and in high NaCl concentrations (6% NaCl, 11 °C; col...

We report here the draft genome sequence of Listeria monocytogenes 2542, a serotype 4b clinical strain recovered from a placental sample during a cheese-related listeriosis outbreak in Portugal.

The association of alginate beads and guar-gum films in a single delivery system was idealized to promote a more effective buccal and oral delivery of bioactive molecules. A response surface method (experimental design approach) was performed to obtain optimal formulations of alginate beads to be incorporated into guar gum oral films as combined bu...

Naturally fermented meat sausages have a long tradition in Mediterranean countries and are one of the most important groups of traditional foods consumed throughout Europe. Despite all the advances in food science and technology and increased regulatory requirements and concerns for safety and quality during the last decades, the challenge to contr...

The potential of constructed wetlands (CWs) as a low technology for wastewater treatment is timely but there is a need to understand the route of pathogenic bacteria (Listeria monocytogenes and Salmonella spp.) and indicator organisms (Enterobacteriaceae and Escherichia coli) present in wastewater within those systems and to what extent they can co...

Contaminated food with Listeria monocytogenes is the predominant route of transmission of listeriosis to humans, a severe illness with a high mortality rate. Food processing environments can be colonized by persistent strains, repeatedly isolated for months or years. This study aimed to investigate the biofilm formation capacity of six strains of L...

Listeria monocytogenes is a foodborne pathogen associated with fermented products. The aim of this study was to characterize anti-listerial bacteriocin produced by lactic acid bacteria (LAB) isolated from Cambodian fermented foods. Four LAB isolates of confirmed bacteriocin production were isolated from fermented fish and shrimp (pha ak trey, ph...

The ongoing rise of antibiotic resistant microbial pathogens has become one of the major public health threats worldwide. Despite all the effort and actions taken so far, a proliferation of antibiotic resistant (AR) and multi-antibiotic resistant (MAR) strains is still observed, including in foodborne pathogens. This trend has been also noted recen...

Listeria monocytogenes is a food-borne pathogen responsible for outbreaks and sporadic cases of listeriosis, a severe invasive disease. Internalin A (InlA) a protein encoded by inlA has a key role in the mechanism of pathogenesis in L. monocytogenes infection, specifically in the invasion of human intestinal epithelial cells. Studies on inlA have s...

This study aimed to investigate the effect of different conditions, including temperature (37 ºC, 22 ºC, and 4 ºC), NaCl concentrations (2.5%, 4%, and 8%), and acidity (pH = 5), on the growth response of persistent and non-persistent isolates of Listeria monocytogenes. The resistance to two common sanitizers (benzalkonium chloride and hydrogen pero...

A significant challenge for traditional food production is to improve its competitiveness by identifying innovations that guarantee the safety of the products, while at the same time meeting general consumer demands and specific consumer expectations towards traditional food (European Research on Traditional Food, EC, DG_Research, 2007). Therefore,...

In Portugal, listeriosis has been notifiable since April 2014, but there is no active surveillance programme for the disease. A retrospective study involving 25 national hospitals led to the detection of an outbreak that occurred between March 2009 and February 2012. The amount of time between the start of the outbreak and its detection was 16 mont...

Listeria monocytogenes is a ubiquitous microorganism responsible for listeriosis, a rare but severe disease in humans, who can become infected by ingesting contaminated food products, namely dairy, meat, fish, and vegetables. Although it can occur in healthy humans, listeriosis mainly affects the elderly, immunocompromised, persons pregnant women,...

Abstract Listeria monocytogenes infection (listeriosis) is an uncommon but severe foodborne illness that affects mainly individuals with recognized underlying conditions: the elderly, immunocompromised individuals, and pregnant women and their fetuses. The aim of this study was to obtain epidemiological data on cases of listeriosis occurring in Por...

Conventional methods for the detection of Listeria monocytogenes in foods and environmental samples relies on selective pre-enrichment, enrichment, and plating. This is followed by confirmation of suspected colonies by testing a limited number of biochemical markers.

Listeria monocytogenes is a ubiquitous bacterium widely distributed in the environment that can cause a severe disease in humans when contaminated foods are ingested. Cheese has been implicated in sporadic cases and in outbreaks of listeriosis worldwide. Environmental contamination, in several occasions by persistent strains, has been considered an...

Abstract The aim of this study was to characterize a broad collection of isolates of Listeria monocytogenes, of different serotypes, recovered in Portugal between 2003 and 2007 from foods (n=353) and from clinical cases of human listeriosis (n=95), in terms of antimicrobial susceptibility. All the isolates were susceptible to ampicillin, the prefer...

Objective. A total of 725 Listeria monocytogenes isolates, 607 from various foods and 118 from clinical cases of listeriosis, were investigated concerning their ability to form biofilms, at 4°C during 5 days and at 37°C during 24 h. Methods. Biofilm production was carried out on polystyrene tissue culture plates. Five L. monocytogenes isolates were...

The effects of previous exposure to sub-lethal acidic and osmotic stresses on the survival of Listeria monocytogenes during exposure to gastro-intestinal (GI) tract simulation, was investigated. Six L. monocytogenes strains isolated from cheeses were selected and exposed to high salt concentrations or acidic conditions and their viability compared...

Pathogenic microorganisms such as Listeria monocytogenes are known to form biofilms. The risk of contamination of food products in the food industry and growth on medical devices in the clinical environment is a cause of concern. The objectives of this work were to examine and compare biofilm formation by food and clinical isolates of L. monocytoge...

In recent years, the number of cases of listeriosis has increased worldwide. Ninety-five isolates of Listeria monocytogenes recovered from Portuguese human cases of listeriosis have been characterized by biotyping (cadmium and arsenic sensitivity), polymerase chain reaction (PCR) grouping, and by pulsed-field gel electrophoresis (PFGE) applying the...

This study was conducted to evaluate the ability of Pediococcus acidilactici HA-6111-2, a PA-1 bacteriocin-producing lactic acid bacterium (LAB), isolated from “Alheira” to inhibit a cocktail of Listeria innocua strains during production and shelf-life of these products. The bacteriocinogenic culture reduced the Listeria population below the detect...