Percorrer por autor "Lopes, Carlos"
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- Carcinogenic Ability of Schistosoma Haematobium Possibly through Oncogenic Mutation of KRAS GenePublication . Botelho, Mónica C.; Veiga, Isabel; Oliveira, Paula A.; Lopes, Carlos; Teixeira, Manuel; Costa, José M Correia da; Machado, José C.Schistosoma haematobium is a parasitic flatworm that infects millions of people, mostly in the developing world, and is associated with high incidence of bladder cancer, although why is not clear. Previously, we have used CD-1 mice to show that Schistosoma haematobium total antigen (Sh) has a carcinogenic ability. Sh intravesically instillation induced the development of several urothelial lesions, namely nodular hyperplasia and dysplasia (LGIUN—Low Grade Intra-Urothelial Neoplasia) after 40 weeks of treatment. These results suggested that Sh induce urothelium malignization. Bladder carcinoma frequently harbours gene mutations that constitutively activate the receptor tyrosine kinase-Ras pathway for this reason we studied activating mutations in KRAS gene. Twenty percent of the bladders with dysplasia presented a KRAS mutation in codon 12 of exon 2. We concluded from these results that the parasite extract of S. haematobium has carcinogenic ability possibly through oncogenic mutation of KRAS gene.
- Disclosing effects of tobacco smoke on occupationally exposed workers at Lisbon restaurantsPublication . Pacheco, Solange; Simoes, Tania; Torres, Vukosawa; Lopes, Carlos; Almeida, Bugalho; Penque, DeborahThis study represents a global assessment of IAQ in Lisbon smoking entertainment places and health effects on exposed workers. Most importantly, it may contribute to the better understanding of pathogenesis mechanisms due to SHS exposure. In addition it may lead to the discovery of specific biomarkers for occupational SHS-exposure that might precede respiratory diseases on their employees and promote more effective therapies.
- Effects of occupational exposure to tobacco smoke: is there a link between environmental exposure and disease?Publication . Pacheco, Solange A.; Torres, Vukosava M.; Louro, Henriqueta; Gomes, Filomena; Lopes, Carlos; Marçal, Nelson; Fragoso, Elsa; Martins, Carla; Oliveira, Cátia L.; Hagenfeldt, Manuela; Bugalho-Almeida, António; Penque, Deborah; Simões, TâniaIn a previous study, evidence was provided that indoor secondhand tobacco smoke (SHS) air pollution remains high in Lisbon restaurants where smoking is allowed, regardless of the protective measures used. The aim of this study was to determine in these locations the levels of polycyclic aromatic hydrocarbons (PAH) associated with the particulate phase of SHS (PPAH), a fraction that contains recognized carginogens, such as benzo[a]pyrene (BaP). Data showed that restaurant smoking areas might contain PPAH levels as high as 110 ng/m(3), a value significantly higher than that estimated for nonsmoking areas (30 ng/m(3)) or smoke-free restaurants (22 ng/m(3)). The effective exposure to SHS components in restaurant smoking rooms was confirmed as cotinine levels found in workers' urine. Considering that all workers exhibited normal lung function, eventual molecular changes in blood that might be associated with occupational exposure to SHS and SHS-associated PPAH were investigated by measurement of two oxidative markers, total antioxidant status (TAS) and 8-hydroxyguanosine (8-OHdG) in plasma and serum, respectively. SHS-exposed workers exhibited higher mean levels of serum 8-OHdG than nonexposed workers, regardless of smoking status. By using a proteomics approach based on 2D-DIGE-MS, it was possible to identify nine differentially expressed proteins in the plasma of SHS-exposed nonsmoker workers. Two acute-phase inflammation proteins, ceruloplasmin and inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4), were predominant. These two proteins presented a high number of isoforms modulated by SHS exposure with the high-molecular-weight (high-MW) isoforms decreased in abundance while low-MW isoforms were increased in abundance. Whether these expression profiles are due to (1) a specific proteolytic cleavage, (2) a change on protein stability, or (3) alterations on post-translational modification pattern of these proteins remains to be investigated. Considering that these events seem to precede the first symptoms of tobacco-related diseases, our findings might contribute to elucidation of early SHS-induced pathogenic mechanisms and constitute a useful tool for monitoring the effects of SHS on occupationally exposed individuals such as those working in the hospitality industry.
- Granulomatous-like immune reaction and hepatic fibrosis induced by Schistosoma haematobium immature wormsPublication . Botelho, Mónica C.; Oliveira, Paula A.; Vieira, Paulo; Delgado, Maria de Lurdes; Lourenço, Ligia; Lopes, Carlos; Machado, José C .; Costa, José M Correia daGolden hamsters were inoculated with Schistosoma haematobium cercariae to examine histological lesions at different time points over an 18 month period of infection. Hamsters were sacrificed 26 weeks and 82 weeks after inoculation. The parasite was found in the blood and in the liver of infected animals as was expected, but we found exclusively male worms, no female worms nor eggs. Interestingly we observed unexpected hepatic lesions induced by S. haematobium immature male worms alone in the golden hamster, characteristic of schistosome eggs. Samples from liver, kidneys, lungs, bladder and gastrointestinal tract were collected during necropsy to evaluate injuries induced by S. haematobium. Notably we observed hepatitis in the liver of infected hamsters, no lesions were found in other organs. We also found liver fibrosis in infected hamsters. This study provides further experimental evidence for the role that schistosome worms, and their derived antigens, may play in the pathology of the infection and modulation of liver chronic inflammation in the murine model of schistosomiasis.
- HFE variants and the expression of iron-related proteins in breast cancer-associated lymphocytes and macrophagesPublication . Marques, Oriana; Rosa, Ana; Leite, Luciana; Faustino, Paula; Rêma, Alexandra; Martins da silva, Berta; Porto, Graça; Lopes, CarlosThe association of HFE (High Iron FE) major variants with breast cancer risk and behavior has been a matter of discussion for a long time. However, their impact on the expression of iron-related proteins in the breast cancer tissue has never been addressed. In the present study, hepcidin, ferroportin 1, transferrin receptor 1 (TfR1), and ferritin expressions, as well as tissue iron deposition were evaluated in a collection of samples from breast cancers patients and analyzed according to the patients’ HFE genotype. Within the group of patients with invasive carcinoma, those carrying the p.Cys282Tyr variant in heterozygosity presented a higher expression of hepcidin in lymphocytes and macrophages than wild-type or p.His63Asp carriers. An increased expression of TfR1 was also observed in all the cell types analyzed but only in p.Cys282Tyr/p.His63Asp compound heterozygous patients. A differential impact of the two HFE variants was further noticed with the observation of a significantly higher percentage of p.Cys282Tyr heterozygous patients presenting tissue iron deposition in comparison to p.His63Asp heterozygous. In the present cohort, no significant associations were found between HFE variants and classical clinicopathological markers of breast cancer behavior and prognosis. Although limited by a low sampling size, our results provide a new possible explanation for the previously reported impact of HFE major variants on breast cancer progression, i.e., not by influencing systemic iron homeostasis but rather by differentially modulating the local cellular expression of iron-related proteins and tissue iron deposition.
- HLA and age of onset in myasthenia gravisPublication . Santos, Ernestina; Bettencourt, Andreia; da Silva, Ana Martins; Boleixa, Daniela; Lopes, Dina; Brás, Sandra; Costa, Paulo Pinho E.; Lopes, Carlos; Gonçalves, Guilherme; Leite, Maria Isabel; da Silva, Berta MartinsThe aetiology of MG is unknown, but both genetic and environmental factors are important. Over the years association of MG with Human Leucocyte Antigens (HLA) has been described in different populations. We investigated a possible association between HLA-DRB1 alleles and age of onset in MG. One hundred and fourteen MG patients (82 females) and 282 control individuals (CP) were studied. Patients were classified according to the age of onset (early-onset <50, n = 74 and late-onset ≥ 50, n = 20). Patients with thymoma (n = 20) were analyzed separately. HLA-DRB1 and HLA-B*08 genotyping was performed using PCR-SSP methodology. HLA-DRB1*03 allele was overrepresented in the global MG. When the early-onset subgroup was considered, this association became even stronger. Regarding the late-onset subgroup, the frequency of HLA-DRB1*01 allele was higher than in the CP. For the thymoma subgroup, the HLA-DRB1*10 allele frequency was significantly higher when compared to the CP. These results have shown a strong association of HLA-DRB1*03 with MG, especially for EOMG also in our population. HLA-DRB1*01 was associated to LOMG suggesting that is a susceptibility factor for this subgroup of the disease. This study confirms a different genetic background of MG subgroups regarding age of onset.
- Human papillomavirus type distribution in cervical intraepithelial neoplasia grade 2/3 and cervical cancer in Portugal: a CLEOPATRE II StudyPublication . Pista, Angela; de Oliveira, Carlos F.; Lopes, Carlos; Cunha, Maria João; CLEOPATRE Portugal Study GroupaOBJECTIVE: Cervical cancer is the third most frequent cancer in women, worldwide and etiologically associated with infection by human papillomavirus (HPV). Following the results of the first epidemiologic population-based CLEOPATRE study in Portugal, it was important to understand the HPV type-specific distribution in women with cervical intraepithelial neoplasia (CIN) grades 2 and 3 and invasive cervical cancer (ICC). METHODS: This was an observational, multicenter, cross-sectional study with retrospective data collection. Between January 2008 and May 2009, paraffin-embedded samples of histologically confirmed cases of CIN2, CIN3, and ICC were collected from the 5 regional health administrations in mainland Portugal. Eligible samples were sent to 2 central laboratories for histological reassessment and HPV genotyping. Prevalence estimates were calculated together with 95% confidence intervals. RESULTS: A total of 582 samples, 177 cases of CIN2, 341 of CIN3, and 64 of ICC, were included. The mean age of participants was 41.8 years (range, 20-88 years). The overall HPV prevalence was 97.9% with a higher prevalence of high-risk genotypes, particularly HPV 16. Multiple infections were observed in 11.2% of the cases. Human papillomavirus prevalence was 95.5% in CIN2, 99.4% in CIN3, and 96.9% in ICC. The 8 more frequent genotypes in order of decreasing frequency were HPV 16, 31, 58, 33, 51, 52, 18, and 35 in CIN2 and HPV 16, 31, 33, 58, 52, 35, 18, and 51 in CIN3. In ICC cases, the 12 detected HPV genotypes were HPV 16, 18, 31, 33, 45, 51, 52, 53, 56, 58, 59, and 73. However, HPV 53 and 73 were always associated to other high-risk genotypes. Human papillomavirus types 31, 51, 52, 56, and 59 were detected in 1 case each. CONCLUSIONS: Human papillomavirus prevalence and patterns of type-specific HPV positivity were comparable with other studies. Current HPV vaccines should protect against HPV genotypes responsible for 77.4% of ICC in Portugal.
- Insight into the molecular basis of Schistosoma haematobium-induced bladder cancer through urine proteomicsPublication . Bernardo, Carina; Cunha, Maria Cláudia; Santos, Júlio Henrique; da Costa, José M Correia; Brindley, Paul J; Lopes, Carlos; Amado, Francisco; Ferreira, Rita; Vitorino, Rui; Santos, Lúcio LaraInfection due to Schistosoma haematobium is carcinogenic. However, the cellular and molecular mechanisms underlying urogenital schistosomiasis (UGS)-induced carcinogenesis have not been well defined. Conceptually, early molecular detection of this phenomenon, through non-invasive procedures, seems feasible and is desirable. Previous analysis of urine collected during UGS suggests that estrogen metabolites, including depurinating adducts, may be useful for this purpose. Here, a new direction was pursued: the identification of molecular pathways and potential biomarkers in S. haematobium-induced bladder cancer by analyzing the proteome profiling of urine samples from UGS patients. GeLC-MS/MS followed by protein-protein interaction analysis indicated oxidative stress and immune defense systems responsible for microbicide activity are the most representative clusters in UGS patients. Proteins involved in immunity, negative regulation of endopeptidase activity, and inflammation were more prevalent in UGS patients with bladder cancer, whereas proteins with roles in renal system process, sensory perception, and gas and oxygen transport were more abundant in subjects with urothelial carcinoma not associated with UGS. These findings highlighted a Th2-type immune response induced by S. haematobium, which seems to be further modulated by tumorigenesis, resulting in high-grade bladder cancer characterized by an inflammatory response and complement activation alternative pathway. These findings established a starting point for the development of multimarker strategies for the early detection of UGS-induced bladder cancer.
- Occupational exposure to environmental tobacco smoke in hospitality venues: are genetic- or proteomics-based biomarkers predictive of respiratory diseases?Publication . Silva, M.J.; Vital, Nádia; Pacheco, Solange; Antunes, Susana; Neves, Sofia; Louro, Henriqueta; Torre, Vukosava M.; Vaz, Fátima; James, Peter; Lopes, Carlos; Marçal, Nelson; Bugalho de Almeida, António; Simões, Tânia; Penque, DeborahEnvironmental tobacco smoke (ETS) is recognized as an occupational hazard in the hospitality industry. Although Portuguese legislation banned smoking in most indoor public spaces, it is still allowed in some restaurants/bars, representing a potential risk to the workers’ health, particularly for chronic respiratory diseases. The aims of this work were to characterize biomarkers of early genetic effects and to disclose proteomic signatures associated to occupational exposure to ETS and with potential to predict respiratory diseases development. A detailed lifestyle survey and clinical evaluation (including spirometry) were performed in 81 workers from Lisbon restaurants. ETS exposure was assessed through the level of PM 2.5 in indoor air and the urinary level of cotinine. The plasma samples were immunodepleted and analysed by 2D-SDSPAGE followed by in-gel digestion and LC-MS/MS. DNA lesions and chromosome damage were analysed innlymphocytes and in exfoliated buccal cells from 19 cigarette smokers, 29 involuntary smokers, and 33 non-smokers not exposed to tobacco smoke. Also, the DNA repair capacity was evaluated using an ex vivo challenge comet assay with an alkylating agent (EMS). All workers were considered healthy and recorded normal lung function. Interestingly, following 2D-DIGE-MS (MALDI-TOF/TOF), 61 plasma proteins were found differentially expressed in ETS-exposed subjects, including 38 involved in metabolism, acute-phase respiratory inflammation, and immune or vascular functions. On the other hand, the involuntary smokers showed neither an increased level of DNA/chromosome damage on lymphocytes nor an increased number of micronuclei in buccal cells, when compared to non-exposed non-smokers. Noteworthy, lymphocytes challenge with EMS resulted in a significantly lower level of DNA breaks in ETS-exposed as compared to non-exposed workers (P<0.0001) suggestive of an adaptive response elicited by the previous exposure to low levels of ETS. Overall, changes in proteome may be promising early biomarkers of exposure to ETS. Likewise, alterations of the DNA repair competence observed upon ETS exposure deserves to be further understood. Work supported by Fundação Calouste Gulbenkian, ACSS and FCT/Polyannual Funding Program.
- Prevention, protocols, and lab capacity: lessons from a norovirus outbreak in the AlgarvePublication . Sá, Regina; Roque, Joana; Marques Mendes, Pedro; Gonçalves, Inês; Sousa, Judite; Matos, Cátia; Júnior, Álvaro; Coelho, Anabela; Belo Correia, Cristina; Manageiro, Vera; Minetti, Corrado; de Sousa, Rita; Horta Correia, Filomena; Lopes, Carlos; Fonseca, Ana; Almeida, Soraia; Ferreira, Maria Jesus; Almendra, Tiago; des Neves, Natalie; Fernandes, Aida; Queiroz, Carolina; Maia, Carla; Bodião, Joaquim; Guerreiro, Ana CristinaThis brief report presents the findings of an epidemiological investigation into a large-scale outbreak of norovirus gastroenteritis that occurred in a hotel in Algarve, Portugal, in August 2022. A total of 244 cases were reported, primarily affecting Portuguese families, with the parents aged 40-50 years and the children aged 0-19 years. Reported symptoms included vomiting, nausea, abdominal pain, and diarrhoea. Norovirus genotype GI.3 [P3] was detected in stool samples from eight probable cases, while food samples tested negative for norovirus and common pathogenic bacteria. The investigation data collected suggest that the source of the outbreak was likely in the hotel's common areas, with subsequent person-to-person transmission in other areas. The final report emphasizes the importance of improving outbreak prevention and control measures, including the development of a foodborne outbreak investigation protocol, the establishment of an outbreak response team, and the enhancement of regional laboratory capacity.