Joana Rolo

• PhD in Biology
• PostDoc Position at University of Beira Interior

The epidemiologically most important mechanism of antibiotic resistance in Staphylococcus aureus is associated with mecA–an acquired gene encoding an extra penicillin-binding protein (PBP2a) with low affinity to virtually all β-lactams. The introduction of mecA into the S. aureus chromosome has led to the emergence of methicillin-resistant S. aureu...

Bacterial vaginosis (BV) is the most frequent vaginal infection worldwide. It is caused by the overgrowth of anaerobic vaginal pathogens such as Gardnerella spp. BV has been associated with the occurrence of dense multispecies biofilms on the vaginal mucosa. Treatment of biofilm-associated infections such as BV is challenging. In this study, we hav...

Candida albicans is the leading cause of vulvovaginal yeast infections; however, other species are becoming relevant in this niche. The spatial distribution of these fungi in the female genital tract remains poorly understood. In this study, swab samples were collected from 33 patients, first from the anterior vulva and then from the upper third an...

Previous studies have revealed that Candida albicans isolates involved in chronic vulvovaginal candidosis (cVVC) phenotypically express less virulent traits than clinical isolates involved in sporadic infections. In this study, we aimed to further explore this finding by studying the behaviour of those same clinical isolates in in-vitro models of i...

Chronic vulvovaginal candidosis results either from reinfection or from the ability of Candida spp. to persist in the vulva and/or vagina. Persistence is usually associated with increased antifungal (mainly azoles) resistance rates, which can explain treatment failure, and/or increased expression of virulence factors by Candida spp. The aim of this...

Natural mineral waters (NMWs) and plant extracts have long been valued for their therapeutic properties and skin benefits. This study investigated, in vitro, the role of five Portuguese NMWs (A-E), combined with plant extracts from five species (Ficus carica L., Rubus idaeus L., Vaccinium myrtillus, Cistus ladanifer and Thymus x citriodorus) as bio...

Background/Objectives: Excessive or inadequate use of antimicrobial drugs may lead to the emergence of resistant strains. For this reason, it is important to monitor consumption indicators to assess drugs’ utilization over time. This study aimed to analyze the consumption of medically prescribed azole antifungal drugs in mainland Portugal from 2014...

Human papillomavirus (HPV)-associated cervical cancer is the most common cancer among women worldwide. The treatment options are strongly related to increased infertility in women. Imiquimod (IQ) is an imidazoquinoline, which has proven antiviral effects against persistent HPV infection by activating immune cells via Toll-like receptors 7/8 when fo...

The interest in the use of probiotics to treat and prevent vaginal infections is known. The new regulation of medical devices by the European Medical Agency (EMA) introduced big changes in Europe regarding probiotic products for vaginal application, as they are no longer considered as medical devices. As the future classification will be as drugs,...

The role of the fungal community, the mycobiota, in the health of the vagina is currently an important area of research. The emergence of new sequencing technologies and advances in bioinformatics made possible the discovery of novel fungi inhabiting this niche. Candida spp. constitutes the most important group of opportunistic pathogenic fungi, be...

The microbiome consists mostly of bacteria, but new evidence and developments in sequencing methods have shown that fungi play an important role in human health and in the stability of the microbiota. Scientific knowledge about the role of commensal fungi in intestinal, oral, vaginal and cutaneous communities has been increasing; however, more stud...

Ethnopharmacological relevance: Thymus mastichina (L.) L. (TM) and Cistus ladanifer L. (CL) are two Portuguese autochthonous species with traditional skin application in folk medicine. TM is majorly known for its antiseptic and wound healing properties, as an external anti-inflammatory agent and for its application in folk cosmetics and hygiene pr...

PurposeDespite the vaginal mucosa is able to respond to allergenic stimuli, vaginal allergic responses have been under investigated in clinical practice. Thus, we aimed to identify the most frequent etiological agents responsible for vulvovaginal allergies, the prevalent signs/symptoms, and the diagnostic tests applied in this clinical condition.Me...

During the past decades, pharmaceutical companies have been making efforts to find alternative methods to animal-based tests. Several tests have been proposed as models for in vitro testing, including oocyte and bovine embryo produced in vitro in developmental toxicity screening. Under optimal experimental conditions, the in vitro maturation rate o...

To use or not to use, that is the first decision to take regarding a drug product. This mandatory step for adherence dictates product efficacy. The determinants for such decision do not only rely on the priority of the therapeutic or preventive strategy but are related to a complex network of perceptions, preferences, personal and cultural backgrou...

Introduction The vast majority of the species of the genus Candida spp. is commensal in humans; however, some are opportunistic pathogens that can cause infection, called candidosis. Among the different types of candidosis, we highlight the vulvovaginal (VVC) which can occur in two main clinical variants: chronic (cVVC) and episodic or sporadic. Th...

Ethnopharmacological relevance Thymus × citriodorus (Pers.) Schreb. is an interspecific hybrid between Thymus pulegioides and Thymus vulgaris, known for its pharmacological activities as diaphoretic, deodorant, antiseptic and disinfectant, the last mostly related with its antimicrobial activity. The folk use of other extracts, as hydrolates, have a...

Dermatophagoides pteronyssinus and Dermatophagoides farinae are the most common House Dust Mite (HDM) species in home environments worldwide and responsible for HDM allergy. Since the prevalence of HDM-related clinical conditions is linked to exposure to the mite itself, the detection of HDM in the human households gains importance. We aimed to dev...

Recurrent vulvovaginal candidiasis (RVVC) is caused by Candida spp., a vaginal colonizer. Despite the clinical importance of RVVC, little is known regarding the characteristics of the disease in Portugal. Thirty-six clinical cases were analyzed, comprising 93 yeast vulvovaginal isolates obtained from women attending a gynecologic consultation at a...

Vulvovaginal candidosis (VVC), caused mainly by the yeast Candida albicans, is the second most prevalent vaginal infection. It has been found to have a large impact on women's quality of life, self-esteem and routines. The prevalence of recurrent vulvovaginal candidosis (RVVC) remains high so the development of alternative treatments is needed. The...

Objective Vulvovaginal candidosis (VVC) is a condition that impacts the quality of life of women worldwide. At least 5–8% of all VVC cases re-occur. Recurrent vulvovaginal candidosis (RVVC) can be defined as the occurrence of a VVC episode at least four times per year. The reasons for recurrence to occur are poorly understood. This work aims to ide...

Aim: Vulvovaginal candidosis (VVC) is the second most common vaginal infection (20-25%), and about 90% of all VVC cases are caused by Candida albicans. Unprotected sexual intercourse has been implicated as one of the risk factors that lead to an outbreak of VVC. To further investigate the relevance of this particular risk factor, in this study, we...

Lactobacillus sp. are well-known colonizers of human mucosa and frequently used as probiotics. Accurate species identification is crucial both for fundamental studies and biotechnology applications; however, it has been thus far challenging. The aim of this work was to develop a one-step multiplex-PCR assay for detection of ten Lactobacillus specie...

Several lines of evidence indicate that the most primitive staphylococcal species, the Staphylococcus sciuri group, were involved in the first stages of evolution of SCC mec — the genetic element carrying the β-lactam resistance gene mecA. However, many steps are still missing from this evolutionary history. In particular, it is not known how mecA...

Epidemiological information of all strains studied. The distribution of the different mecA homologue alleles in the population of isolates studied is also shown. Phylogenetic group (S. sciuri sciuri, S. sciuri rodentius, S, sciuri carnaticus, S. sciuri new subspecies group 1, S. sciuri new subspecies group 2, S. vitulinus, S. fleurettii), origin of...

Distribution of oxacillin MICs of S. sciuri (A) and S. vitulinus (B) as determined by Etest. “Wild-type” S. sciuri strains: S. sciuri strains carrying mecA1 only; “Resistant” S. sciuri strains: S. sciuri strains carrying mecA1 and mecA. “Wild-type” S. vitulinus strains: S. vitulinus strains carrying mecA2; “Resistant” S. vitulinus strains: S. vitul...

Percentage of nucleotide identity and size of the core genes of the 76 S. sciuri isolates from this study. (XLSX)

Marginal likelihoods for the strict, fixed, random and uncorrelated molecular clock models under a constant size population model. (XLSX)

Bayes factors for the strict, fixed, random and uncorrelated molecular clock models under a constant size population model. (XLSX)

Phylogenetic analysis of the mecA homologues nucleotide sequence. mecA homologues. The sequences of each mec homologue gene was extracted from the de novo assembly contigs and aligned with ClustalW. The tree was performed with UPGMA method, under the Jukes-Cantor substitution model, with a bootstrap of 100 replicates. The unrooted tree is shown (A)...

Phylogenetic analysis of the core genome of isolates belonging to the sciuri group. Unrooted phylogenetic tree based on the number of SNP differences found among the predicted core genome of the strains. The reference genome used was S. fleurettii 402567. S. fleurettii (A). S. vitulinus (B). S. sciuri (C). (TIF)

Bacterial species comprise related genotypes that can display divergent phenotypes with important clinical implications. Staphylococcus epidermidis is a common cause of nosocomial infections and, critical to its pathogenesis, is its ability to adhere and form biofilms on surfaces, thereby moderating the effect of the host's immune response and anti...

The opportunistic pathogens Staphylococcus aureus and Staphylococcus epidermidis represent major causes of severe nosocomial infection, and are associated with high levels of mortality and morbidity worldwide. These species are both common commensals on the human skin and in the nasal pharynx, but are genetically distinct, differing at 24% average...

Previous studies produced evidence that mecA, the determinant of β-lactam resistance in methicillin-resistant Staphylococcus aureus (MRSA), may have originated in the most primitive and widespread animal commensal species-Staphylococcus sciuri. But how the mecA homologue (mecA1/pbpD) was captured from S. sciuri into the staphylococcal cassette chro...

Methicillin resistance in Staphylococcus spp. results from the expression of an alternative penicillin-binding protein 2a (encoded by mecA) with a low affinity for β-lactam antibiotics. Recently, a novel variant of mecA known as mecC (formerly mecALGA251) was identified in Staphylococcus aureus isolates from both humans and animals. In this study,...

Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of infection in the community (CA-MRSA), but in spite of its relevance, no data exist concerning its epidemiology in Portugal. In this study, we aimed to evaluate the prevalence, population structure, and origin of MRSA in the Portuguese community. A total of 527 isolates, both m...

Antibiotic resistance is a serious problem in Staphylococcus epidermidis infections as many clinical isolates of this organism are resistant to up to eight different antibiotics. The increased resistance to conventional antibiotic therapy has lead to the search for new antimicrobial therapeutic agents. Farnesol, an essential oil found in many plant...

Several studies have addressed the epidemiology of community-associated Staphylococcus aureus (CA-SA) in Europe; nonetheless, a comprehensive perspective remains unclear. In this study, we aimed to describe the population structure of CA-SA and to shed light on the origin of methicillin-resistant S. aureus (MRSA) in this continent. A total of 568 c...

Additional molecular and epidemiological information. (DOCX)

Little is known about the clonality of Staphylococcus epidermidis in the United States, although it is the predominant pathogen in infections involving prosthetic materials, including ventricular assist devices (VADs). Seventy-five VAD recipients at 4 geographically diverse US cardiac centers were prospectively followed up to 1 year of VAD support....

Staphylococcus epidermidis is a harmless commensal, but it can become a human pathogen, mainly in the hospital environment. In order to clarify strategies used by these bacteria to adapt to the hospital environment, we compared the population structure and staphylococcal cassette chromosome mec (SCCmec) content of S. epidermidis from the community...

Polymerase chain reaction (PCR) amplification of antibiotic resistance genes as well as staphylococcal cassette chromosome mec (SCCmec) typing and pulsed-field gel electrophoresis (PFGE) of SmaI macrorestriction fragments of genomic DNA were used to characterize 45 methicillin-resistant coagulase-negative staphylococci (MRCoNS) isolates responsible...