Percorrer por autor "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.
- Early diagnosis of acid sphingomyelinase deficiency (ASMD) through biomarkers analysisPublication . Neiva, Raquel; da Silva Gaspar, Paulo Jorge Miranda; Sousa e Silva, Lisbeth Elena; Gonçalves, I.; Ferreira, S.; Diogo, Luisa; Vilarinho, LauraIntroduction: Acid sphingomyelinase deficiency (ASMD), historically known as Niemann–Pick disease (NPD) types A, A/B, and B, is a rare, progressive, potentially fatal lysosomal storage disease caused by pathogenic variants in SMPD1 gene. It presents a wide spectrum of symptoms, age of onset, and degree and type of organ effected. The disease manifestations frequently involve hepatosplenomegaly with progressive organ dysfunction, interstitial lung disease, and bleeding. In this work, we will present a patient whose lysosomal biomarkers study allowed the diagnosis of ASMD. Methods: This patient had hepatosplenomegaly, elevated transaminases in which the primary clinical suspicion was an acid lipase deficiency. By the analysis of our multiplex biomarker panel by LC-MS/MS analysis, we were able to do a differential diagnosis. Results/Case report: The lysosphingomyelin (lysoSM) and lysosphingomyelin-509 (lysoSm-509) were approximately 100 a 150x than normal, suggestive of Niemann–Pick disease. The diagnosis of ASMD was confirmed by reduced acid sphingomyelinase enzyme activity measured in peripheral blood leukocytes and the presence of a pathogenic variant in both alleles in the SMPD1 gene. Conclusion: ASMD can be underestimate and the diagnostic odissey arise from an overlap in symptomology with other diseases, including primary hepatic disease, Gaucher disease, Niemann–Pick disease, and lysosomal acid lipase deficiency. The multiplex biomarker panel, with different lysolipids, allows simultaneously diagnosis of different LSDs, in a timely manner, leading to an early intervention, before the appearance of more deleterious symtpoms.
- Early Diagnosis of Mucopolysaccharidoses in PediatricsPublication . da Silva Gaspar, Paulo Jorge Miranda; Neiva, Raquel; Sousa e Silva, Lisbeth Elena; Diogo, Luisa; Ferreira, A.; Miranda, A.; Ribeiro, S.; Antunes, D.; Garcia, P.; Rodrigues, E.; Campos, T.; Janeiro, P.; Lopes, Altina; Pereira, Cristina; Nogueira, Célia; Sousa, S.; Ferreira, S.; Alves, Sandra; Leão Teles, Elisa; Vilarinho, LauraIntroduction: Mucopolysaccharidoses (MPSs) are a group of Lysosomal Storage Disorders with multisystem involvement, presenting different degrees of severity and evolution. At early disease stages and late onset forms, diagnosis can be postponed for years or even missed. The FIND PROJECT was designed to claim awareness to the redflags of MPSs at pediatric age and to provide a useful tool for physicians to diagnose these pathologies, since most of them are amenable to enzyme replacement therapy.
- Early Diagnosis of Mucopolysaccharidoses in PediatricsPublication . Gaspar, Paulo; Neiva, Raquel; Silva, Lisbeth; Diogo, L.; Ferreira, A.; Miranda, A.; Ribeiro, S.; Antunes, D.; Garcia, P.; Rodrigues, E.; Campos, T.; Janeiro, P.; Lopes. Altina; Pereira, Cristina; Nogueira, Célia; Nogueira, C.; Sousa, S.; Ferreira, S.; Alves, S.; Teles, E.; Vilarinho, LauraIntroduction: Mucopolysaccharidoses (MPSs) are a group of Lysosomal Storage Disorders with multisystem involvement, presenting different degrees of severity and evolution. At early disease stages and late onset forms, diagnosis can be postponed for years or even missed. The FIND PROJECT was designed to claim awareness to the red flags of MPSs at pediatric age and to provide a useful tool for physicians to diagnose these pathologies, since most of them are amenable to enzyme replacement therapy. Methods: MPSs clinical suspicious were addressed by performing seven distinct enzymatic assays in dried blood spots, in order to understand whether any of those specific enzymes was deficient. For positive cases, the identification of glycosaminoglycans and the molecular study is carried out. Results/Case report: In the first eight years of the project, we have identified 12 patients (five MPS I; one MPS II; two MPS IIIB, one MPS IVA, two GM1 and one MPS VI) out of the 385 samples studied. In the majority of the patients identified, the age of diagnosis was less than 3 years of age, which is much lower when compared to the mean age of diagnosis of 6 years old, reported by Pinto et al, 2004. Conclusion: These results, shows that this project was successful also in its educational component, by raising the concern and awareness for these multisystemic pathologies that are linked to high morbidity.
- 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.