Browsing by Author "Ferreira, S."
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- Anti-cancer potential of Fasciola hepatica extractsPublication . Ferreira, S.; Fernandes, R.; Alves, H.; Richter, J.; Botelho, M.C.Fascioliasis is a food borne disease caused by infection with a liver fluke termed Fasciola (F.) hepatica. Fascioliasis, as a neglected tropical disease, commonly affects poor people from developing countries. It has been estimated that at least 2.6 million people are infected with fascioliasis worldwide. According to the International Agency for Research on Cancer, two other liver flukes Opistorchis viverrini and Clonorchis sinensis) have been recognized as definitive causes of cancer (IARC, 2012). On the other hand even long-lasting and/ or repeated F. hepatica infections have not been associated with cancer, so far. There are any known causative associations between this parasite and cholangiocarcinoma or liver cancer.
- Arcobacter spp. in food chain – From culture to omicsPublication . Ferreira, S.; Oleastro, M.; Domingues, F.Book description by editor: Food is an essential means for humans and other animals to acquire the necessary elements needed for survival. However, it is also a transport vehicle for foodborne pathogens, which can pose great threats to human health. Use of antibiotics has been enhanced in the human health system; however, selective pressure among bacteria allows the development for antibiotic resistance. Foodborne Pathogens and Antibiotic Resistance bridges technological gaps, focusing on critical aspects of foodborne pathogen detection and mechanisms regulating antibiotic resistance that are relevant to human health and foodborne illnesses This groundbreaking guide: - Introduces the microbial presence on variety of food items for human and animal consumption; - Provides the detection strategies to screen and identify the variety of food pathogens in addition to reviews the literature; - Provides microbial molecular mechanism of food spoilage along with molecular mechanism of microorganisms acquiring antibiotic resistance in food; - Discusses systems biology of food borne pathogens in terms of detection and food spoilage; - Discusses FDA’s regulations and Hazard Analysis and Critical Control Point (HACCP) towards challenges and possibilities of developing global food safety. Foodborne Pathogens and Antibiotic Resistance is an immensely useful resource for graduate students and researchers in the food science, food microbiology, microbiology, and industrial biotechnology.
- Classification of the dup 15q13.3 CNV: A National data collectionPublication . Sousa, A.; Serafim, S.; Santos, R.; Custódio, S.; Ávila, M.; Dupont, J.; Dias P, P.; Moldovan, O.; Melo, J.; Ferreira, S.; Pires, L.; Leão, M.; Sá, S.; Prior, C.; Alves, C.; Barreta, A.; Tarelho, A.; Marques, B.; Pedro, S.; Lopes, F.; Maciel, P.; Correia, H.; Dória, S.; Rendeiro, P.; Castedo, S.; Carreira, I.; Sousa, A.B.Introduction: The proximal region 15q11q14 is one of the most unstable regions in the human genome, with six recognizable break points (BP1-BP6). In 15q13.3 there is a recurrent small CNV (BP4-BP5) consisting of a 350-680 Kb duplication, encompassing the CHRNA7 gene, which encodes the alpha 7 subunit of the neuronal nicotinic acetylcholine receptor. Although microdeletions of CHRNA7 are known to cause intellectual disability and neuropsychiatric phenotypes with high penetrance, the patogenicity of CHRNA7 duplications remains unclear. Microduplication 15q13.3 seems to be associated with a phenotypic spectrum of cognitive impairment and neuropsychiatric/neurobehavioral disorders. However, the penetrance of this CNV is considered incomplete since it is present in clinically unaffected individuals in the general population and it is frequently inherited from apparently clinically normal parents. Nonetheless, some pedigree studies have found a history of neuropsychiatric problems among carrier family members. This study aimed at re-evaluating the dup 15q13.3 CNV in national laboratories. Materials and Methods: Our study collected data on 15q13.3 microduplications in eight Portuguese genetics laboratories, among subjects referred for microarray. Results: Here we present a total of seventeen cases with dup 15q13.3. The subjects had somewhat variable phenotypes, with a bias towards developmental delay and autism spectrum disorders. Inheritance was established for eight of the subjects, and the majority originated from the father. We had no access to clinical data on carrier parents. No de novo CNV was found. All laboratories involved classified this variant as of uncertain significance. Discussion/Conclusion: To better determine whether this CNV is benign or pathogenic, careful characterization of patient and control cohorts must be performed, including detailed patient phenotyping, inheritance, clinical evaluation of carrier parents, prevalence in controls, as well as genetic functional studies. We strongly support the creation of a national database for uncertain CNVs in order to clarify the relevance of these recurrent findings, allowing a definitive classification in either pathogenic or benign.
- Differential diagnosis of Autism Spectrum Disorder (ASD) by CNV detection – can early diagnosis be improved?Publication . Kwiatkowska, K.; Conceição, I.C.; Rodrigues, A.C.; Picanço, I.; Marques, I.; Melo, J.; Ferreira, S.; Café, C.; Almeida, J.; Mouga, S.; Oliveira, G.; Vicente, A.M.Autism Spectum Disorder (ASD) is an impairment in neurodevelopment that can be recognized in the first years of life. Symptoms are diverse and vary in severity, determining prognosis and influencing the integration in the community. ASD is characterized by difficulties in interpersonal interaction, verbal and nonverbal communication, and by uncommon interests, inappropriate and uncontrolled behaviors, and repetitive activities. Specific and early diagnosis allows early and effective intervention that improves learning, communication and social skills of autistic children.
- Distinct spectrum of apc germline mutations in familial adenomatous polyposis at the center-south of portugal: identification of a mutational hotspot and suggestion of a founder effectPublication . Filipe, B.; Claro, I.; Lage, P.; Ferreira, S.; Rosa, I.; Rodrigues, P.; Spier, I.; Theisen, Patrícia; Pereira-Caetano, Iris; Isidro, Glória; Gonçalves, João; Aretz, S.; Dias Pereira, A.; Albuquerque, C.Introduction: Familial adenomatous polyposis (FAP) is caused by APC germline mutations. These have been reported in classic and attenuated FAP (AFAP) but only two hotspots were described (codons 1309 and 1061-range:0-15%). We aimed to characterize the APC mutation spectrum in a FAP/AFAP population from the familial polyposis registry of the Portuguese Oncology Institute in Lisbon. Methods: We performed mutation analysis in 95 index patients from our FAP/AFAP cohort (61 FAP; 34 AFAP) using PTT, DGGE, sequencing and MLPA. Haplotype analysis was performed using 3 microsatellite markers flanking APC and 2 intragenic SNPs in 12 families with an intron 9 mutation (6 from our registry, 2 from INSA and 4 from IHG), occasionally detected in the literature, in order to evaluate a possible founder effect. All samples were anonymized. Statistics: Fisher’s exact and Χ2. Results: APC mutations were found in 47/61(77%) FAP and in 12/34(35%) AFAP families. The 1309del and 1061del contributed for 6/59(10%) and 2/59(4%) of the families, respectively. Exon 15 mutations were more frequent in FAP than in AFAP [30/47(64%) vs 1/12(8%),P<0.001]. A high mutation frequency was also found in exon 9 and flanking regions (9/59;15%), contributing for the majority of AFAP with APC mutation (8/12;67%). An intron 9 mutation (c.1312+3A>G) was highly represented (6/59,10%), exclusively in AFAP (6/12;50%). Segregating with this mutation, we detected a common haplotype apparently shared by 6 families. For D5S346, the common allele segregating with this haplotype was more frequent in the index patients (11/20;46%) than in a control population (20/90;22%). Discussion: We identified a specific distribution of APC mutations and a mutational hotspot in our population. The higher frequency of the c.1312+3A>G mutation in Center-South Portugal suggest a non-uniform distribution which may be explained by a founder effect. Further studies using SNPs flanking intron 9 and the analysis of more families/relatives are needed.
- Genotypic and phenotypic features of Arcobacter butzleri pathogenicityPublication . Ferreira, S.; Queiroz, J.A.; Oleastro, M.; Domingues, F.C.Even though Arcobacter butzleri has been implicated in some human disease as diarrhoea and bacteraemia, much of its pathogenesis and virulence factors remain unclear. In this work we have compared pathogenic and genotypic properties of six A. butzleri isolates from human and non-human sources. The tested isolates showed to be susceptible to tetracyclines and aminoglycosides, however non-human isolates were all resistant to quinolones. The ability to form biofilms was variable among the tested strains, and all of them showed a weak haemolytic activity. The presence of nine putative virulence genes was determined, with cadF, ciaB, cj1349, mviN, pldA, tlyA being detected in all strains, while irgA (3/6), hecA (5/6), hecB (4/6) were detected only in some strains. High levels of adhesion were observed for A. butzleri on Caco-2 cells, with pre-existing inflammation showing no significant effect on the adherence ability; yet variable levels of invasion were observed. A. butzleri isolates were able to survive intracellularly in Caco-2 cells and to induce a significant up-regulation of interleukin-8 secretion and structural cell rearrangements. These data brings new insights on A. butzleri virulence and highlights its pathogenic potential.
- Insights in the pathogenesis and resistance of Arcobacter: A reviewPublication . Ferreira, S.; Queiroz, J.A.; Oleastro, Mónica; Domingues, F.C.Arcobacter genus currently comprises 18 recognized species, among which Arcobacter butzleri, Arcobacter cryaerophilus and Arcobacter skirrowii have been associated with human and animal disease. Although these organisms, with special emphasis A. butzleri, are emerging as clinical pathogens, several aspects of their epidemiology and virulence are only starting to be clarified. In vitro human and animal cell culture assays have been used to show that several Arcobacter species can adhere to and invade eukaryotic cells, induce an immune response and produce toxins that damage host cells. In addition, data from genome sequencing highlighted several potential markers that may be helpful candidates for the study and understanding of these mechanisms; however, more work is necessary to clarify the molecular mechanisms involved in Arcobacter virulence. Arcobacter can be considered a relatively robust organism showing to be able to survive in adverse conditions, as the ones imposed by food processing and storage. Moreover, these bacteria have shown increased antibiotic resistance, along with high multidrug resistance. In this review, we seek to update the state-of-the-art concerning Arcobacter distribution, its interaction with the host, the trends of antibiotic resistance, its ability to survive, and finally the use of natural antimicrobials for control of Arcobacter.
- Resveratrol against Arcobacter butzleri and Arcobacter cryaerophilus: activity and effect on cellular functionsPublication . Ferreira, S.; Silva, F.; Queiróz, J.A.; Oleastro, M.; Domingues, F.C.The frequent isolation of Arcobacter butzleri and Arcobacter cryaerophilus from food samples makes it imperative to search for potential compounds able to inhibit the development of these bacteria. Taking this into consideration, this study focuses on the antimicrobial activity of resveratrol and its mechanism of action against A. butzleri and A. cryaerophilus. The activity of resveratrol was assessed by a microdilution method and time– kill curves. Resveratrol effect on cellular functions was assessed by flow cytometry evaluating intracellular DNA content and metabolic activity. Ethidium bromide (EtBr) accumulation in the presence of resveratrol was also evaluated, as well as the susceptibility to resveratrol in the presence of phenylalanine-arginine β- naphthylamide (PAβN). Scanning electron microscopy (SEM) was used to further evaluate cell damage caused by resveratrol. Resveratrol presented MIC values of 100 and 50 μg/mL to A. butzleri and A. cryaerophilus, respectively. Based on the time–kill curves, resveratrol exhibited bactericidal activity, leading to a ≥3 log10 CFU/mL reduction of initial inoculums, for A. butzleri exponential phase cells incubated for 6 h with 1× MIC or with 2× MIC after 24 h for stationary phase cells. For A. cryaerophilus cells in exponential growth phase, 99.9% killing was achieved after 24 h incubation with 2× MIC,whereas, for stationary phase cells, bactericidal activitywas only detected after incubation with 4×MIC. Incubation with resveratrol led to a decrease in both intracellular DNA content and metabolic activity. An increase in the accumulation of EtBr was observed in the presence of resveratrol, and the efflux pump inhibitor PAβN reduced the MIC of resveratrol. SEM analysis revealed disintegration of A. butzleri cells treated with resveratrol, whereas no morphological alteration was observed for A. cryaerophilus cells. Resveratrol has a good anti-Arcobacter activity, and the results obtained suggest that this compound could act through several different mechanisms in the inhibition of this microorganism. The results encourage the use of this compound for the development of potential strategies to control Arcobacter in food products.
- Self-assembled dextrin nanogel as protein carrier: Controlled release and biological activity of IL-10Publication . Carvalho, V.; Castanheira, P.; Madureira, P.; Ferreira, S.; Costa, C.; Teixeira, João Paulo; Faro, C.; Vilanova, M.; Gama, M.Interleukin-10 (IL-10) is an anti-inflammatory cytokine, which active form is a non-covalent homodimer. Given the potential of IL-10 for application in various medical conditions, it is essential to develop systems for its effective delivery. In previous work, it has been shown that a dextrin nanogel effectively incorporated and stabilized rIL-10, enabling its release over time. In this work, the delivery system based on dextrin nanogels was further analyzed. The biocompatibility of the nanogel was comprehensively analyzed, through cytotoxicity (lactate dehydrogenase (LDH) release, MTS, Live, and Dead) and genotoxicity (comet) assays. The release profile of rIL-10 and its biological activity were evaluated in vivo, using C57BL/6 mice. Although able to maintain a stable concentration of IL-10 for at least 4 h in mice serum, the amount of protein released was rather low. Despite this, the amount of rIL-10 released from the complex was biologically active inhibiting TNF-α production, in vivo, by LPS-challenged mice. In spite of the significant stabilization achieved using the nanogel, rIL-10 still denatures rather quickly. An additional effort is thus necessary to develop an effective delivery system for this cytokine, able to release active protein over longer periods of time. Nevertheless, the good biocompatibility, the protein stabilization effect and the ability to perform as a carrier with controlled release suggest that self-assembled dextrin nanogels may be useful protein delivery systems.
- The alpha-galactosidase A p.Arg118Cys variant does not cause a Fabry disease phenotype: data from individual patients and family studiesPublication . Ferreira, S.; Ortiz, A.; Germain, D.P.; Viana-Baptista, M.; Caldeira-Gomes, A.; Camprecios, M.; Fenollar-Cortés., M; Gallegos-Villalobos, Á.; Garcia, D.; García-Robles, J.A.; Egido, J.; Gutiérrez-Rivas, E.; Herrero, J.A.; Mas, S.; Oancea, R.; Péres, P.; Salazar-Martín, L.M.; Solera-Garcia, J.; Alves, H.; Garman, S.C.; Oliveira, J.P.Lysosomal α-galactosidase A (α-Gal) is the enzyme deficient in Fabry disease (FD), an X-linked glycosphingolipidosis caused by pathogenic mutations affecting the GLA gene. The early-onset, multi-systemic FD classical phenotype is associated with absent or severe enzyme deficiency, as measured by in vitro assays, but patients with higher levels of residual α-Gal activity may have later-onset, more organ-restricted clinical presentations. A change in the codon 118 of the wild-type α-Gal sequence, replacing basic arginine by a potentially sulfhydryl-binding cysteine residue - GLA p.(Arg118Cys) -, has been recurrently described in large FD screening studies of high-risk patients. Although the Cys118 allele is associated with high residual α-Gal activity in vitro, it has been classified as a pathogenic mutation, mainly on the basis of theoretical arguments about the chemistry of the cysteine residue. However its pathogenicity has never been convincingly demonstrated by pathology criteria. We reviewed the clinical, biochemical and histopathology data obtained from 22 individuals of Portuguese and Spanish ancestry carrying the Cys118 allele, including 3 homozygous females. Cases were identified either on the differential diagnosis of possible FD manifestations and on case-finding studies (n=11; 4 males), or on unbiased cascade screening of probands' close relatives (n=11; 3 males). Overall, those data strongly suggest that the GLA p.(Arg118Cys) variant does not segregate with FD clinical phenotypes in a Mendelian fashion, but might be a modulator of the multifactorial risk of cerebrovascular disease. The Cys118 allelic frequency in healthy Portuguese adults (n=696) has been estimated as 0.001, therefore not qualifying for "rare" condition.