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- Blackbirds Turdus merula as competent reservoirs for Borrelia turdi and Borrelia valaisiana in Portugal: evidence from a xenodiagnostic experimentPublication . Norte, A.C.; Lopes de Carvalho, I.; Núncio, M.S.; Ramos, J.A.; Gern, L.To confirm that thrushes, such as blackbirds Turdus merula, play a role as reservoir for some Borrelia genospecies, we performed a xenodiagnostic experiment with blackbirds captured in a mixed wood located in Western Portugal where Borrelia turdi, an uncommon genospecies in Europe, was the most prevalent genospecies associated with birds. Two out of five birds harboured B. turdi infected Ixodes frontalis at the time of capture. Four out of five birds transmitted spirochaetes to Ixodes ricinus xenodiagnostic ticks: two birds transmitted Borrelia valaisiana to 25.7% and 10.5% of ticks, and two transmitted B. turdi to 6.4% and 5.4% of ticks. Our results showed that blackbirds transmit B. valaisiana and B. turdi to I. ricinus feeding larvae, acting as reservoir hosts for these genospecies in nature.
- Occupational exposure to Aflatoxin B1: the case of poultry and swine productionPublication . Viegas, S.; Veiga, L.; Figueiredo, P.; Almeida, A.; Carolino, E.; Sabino, R.; Verissimo, C.; Viegas, C.Although there is an abundance of literature concerning the ingestion of food contaminated with aflatoxin B1 (AFB1), only a small number of studies explore mycotoxin exposure in occupational settings. Taking this into consideration, our study was developed with the intention of elucidating whether there is occupational exposure to AFB1 in Portuguese poultry and swine production facilities. A specific biomarker was used to assess exposure to AFB1. A total of 45 workers (34 from poultry farms; 11 from swine production facilities) participated in this study, providing blood samples. Additionally, a control group (n=30) composed of subjects without any type of contact with agricultural activity was considered. All participants signed a consent form and were provided with the study protocol. Eighteen poultry workers (58.6%) and six workers from the swine production facilities (54.5%) showed detectable levels of AFB1. In the control group, the AFB1 values were all below 1 ng/ml. No significant differences in AFB1 levels in serum between workers from poultry and swine farms were found. Poultry workers, however, showed the highest serum levels and a significant statistical difference between this group and the control group was found. Results suggest that exposure to AFB1 by inhalation occurs in both occupational settings representing an additional risk that needs to be recognised, assessed and prevented.
- The State of Hepatitis B and C in the Mediterranean and Balkan Countries: Report from a Summit ConferencePublication . Hatzakis, A.; Van Damme, P.; Alcorn, K.; Gore, C.; Benazzouz, M.; Berkane, S.; Buti, M.; Carballo, M.; Cortes Martins, H.; Deuffic-Burban, S.; Dominguez, A.; Donoghoe, M.; Elzouki, A.N.; Ben-Alaya Bouafif, N.; Esmat, G.; Esteban, R.; Fabri, M.; Fenton, K.; Goldberg, D.; Goulis, I.; Hadjichristodoulou, C.; Hatzigeorgiou, T.; Hamouda, O.; Hasurdjiev, S.; Hughes, S.; Kautz, A.; Malik, M.; Manolakopoulos, S.; Matičič, M.; Papatheodoridis, G.; Peck, R.; Peterle, A.; Potamitis, G.; Prati, D.; Roudot-Thoraval, F.; Reic, T.; Sharara, A.; Shennak, M.; Shiha, G.; Shouval, D.; Sočan, M.; Thomas, H.; Thursz, M.; Tosti, M.; Trépo, C.; Vince, A.; Vounou, E.; Wiessing, L.; Manns, M.The burden of disease due to chronic viral hepatitis constitutes a global threat. In many Balkan and Mediterranean countries, the disease burden due to viral hepatitis remains largely unrecognized, including in high-risk groups and migrants, because of a lack of reliable epidemiological data, suggesting the need for better and targeted surveillance for public health gains. In many countries, the burden of chronic liver disease due to hepatitis B and C is increasing due to ageing of unvaccinated populations and migration, and a probable increase in drug injecting. Targeted vaccination strategies for hepatitis B virus (HBV) among risk groups and harm reduction interventions at adequate scale and coverage for injecting drug users are needed. Transmission of HBV and hepatitis C virus (HCV) in healthcare settings and a higher prevalence of HBV and HCV among recipients of blood and blood products in the Balkan and North African countries highlight the need to implement and monitor universal precautions in these settings and use voluntary, nonremunerated, repeat donors. Progress in drug discovery has improved outcomes of treatment for both HBV and HCV, although access is limited by the high costs of these drugs and resources available for health care. Egypt, with the highest burden of hepatitis C in the world, provides treatment through its National Control Strategy. Addressing the burden of viral hepatitis in the Balkan and Mediterranean regions will require national commitments in the form of strategic plans, financial and human resources, normative guidance and technical support from regional agencies and research.
- Children Exposure assessment to patulin through the intake of apple based productsPublication . Pereira, Catarina; Alvito, Paula; Seljak, Barbara; Vasco, ElsaNowadays, food safety is of major concern since more chemicals are present in our environment. Food is an important route of exposure to contaminants as mycotoxins. Patulin (PAT) is a toxic secondary metabolite produced by a wide range of fungal species growing on fruit, including apples, pears, grapes and others. Children are a vulnerable part of the population due to, in part, their physiology, a fairly restricted diet and a higher intake relative to their body. Within the safety evaluation procedure of any chemical substance, one crucial step is the dietary exposure assessment. Exposure assessment combines data on concentrations of a chemical substance present in food with the quantity of those foods consumed. Food consumption data are an essential element for risk assessment and EFSA recommended the application of weighed food diaries as main dietary assessment method for 0-36 months children. An online software to entry consumption data are a very useful tool for exposure assessment. The Open Platform for Clinical Nutrition (OPEN) is a Web-based application that provides clinical dietitians and the general population with an online dietary assessment and diet planning tool. It can be used with any food composition dataset that complies with the EuroFIR standards for data harmonisation. In Portugal no data are available on child consumption between 0-36 months and data on mycotoxins occurrence in baby foods are scarce. The main objectives of this study were to: i) determine the contents of patulin in apple based foods, ii) develop tools and procedures for the collection of individual food consumption data for infants, iii) test the above mentioned tools and procedures within a pilot dietary survey and iv) analyse the collected data and evaluate the tools and procedures used, providing recommendations for potential improvements and/or revisions.
- Validation of A HPLC-UV Method for the Simultaneous Determination of Acesulfame K, Saccharin And Aspartame in Tabletop Intense SweetenersPublication . Veiga, Cláudia; Serra, Celeste; Vasco, ElsaIntroduction Arti'cial sweeteners are substances of low calori'c value, used as food additives to give a!sweet taste to foodstu(s, reducing the energy supplied by them. It is well known that the increase of sugar consumption is related with two severe health problems diabetes and obesity. In this way, arti'cial sweeteners are normally used in dietetic products and o)en present in so) drinks and tabletop intense sweeteners, among others products. In order to obtain consistent, reliable and accurate data it is important to use validated methods. Only in this way, obtained occurrence results could be used in exposure studies to evaluate the intake of arti'cial sweeteners by Portuguese population. In this study a!method of high performance liquid chromatography with ultraviolet detection (HPLC- UV) for simultaneous determination of acesulfame k, saccharin and aspartame in tabletop intense sweeteners was developed and validated. Method validation was performed in order to obtain accreditation by ISO 17025. Experimental Method /e analytical method, based on EN 12856, was performed in a!PrevailTM C18 (250 x 4.6mm, 5 μm) column, with the mobile phase phosphate bu(er:acetonitrile (95:5 V/V) and a!=ow rate of 1 ml/min. Detection wavelength was 220 nm for all the sweeteners. Identi'cation was carried out on the basis of the retention time and quantita- tive determination by external standard method. /e method validation included the evaluation of calibration curve parameters, limits, repeatability, precision and accuracy according to the criteria established by ISO 8466 and ISO 5725. /e precision study was performed with tabletop intense sweeteners in granulated, liquid and tablet form, which were purchased from supermarkets in Lisbon city, Portugal, between October and November 2012.Results /e method was validated in a!working range of 4-40 μg/mL for acesulfame k and saccharin and 3.6-36 μg/mL for aspartame. /e values obtained for the limits of detection (LOD) and quanti'cation (LOQ) were 1-4 μg/mL (0.1-0.4 g/kg of sample) for acesulfame k, 0.3-4 μg/mL (0.03-0.4 g/kg of sample) for saccharin and 0.5-3.6 μg/mL (0.05-0.36 g/kg of sample) for aspartame, respectively. /e repeatability (RSDr%) and the precision (RSDR%) ranged from 0.95 to 4.33 and from 1.71 to 5.21, respectively. /e absolute z-scores ob- tained in accuracy evaluation was <2. Conclusion /e method proposed in this work allows the simultaneous quanti'cation of acesulfame k, saccharin and aspartame and proved to be accurate for the determination of these additives in tabletop intense sweeteners.
- SNP typing reveals similarity in Mycobacterium tuberculosis genetic diversity between Portugal and Northeast BrazilPublication . Lopes, João S.; Marques, Isabel; Soares, Patricia; Nebenzahl-Guimaraes, Hanna; Costa, João; Miranda, Anabela; Duarte, Raquel; Alves, Adriana; Macedo, Rita; Duarte, Tonya A.; Barbosa, Theolis; Oliveira, Martha; Nery, Joilda S.; Boechat, Neio; Pereira, Susan M.; Barreto, Mauricio L.; Pereira-Leal, José; Gomes, Maria Gabriela Miranda; Penha-Goncalves, CarlosHuman tuberculosis is an infectious disease caused by bacteria from the Mycobacterium tuberculosis complex (MTBC). Although spoligotyping and MIRU-VNTR are standard methodologies in MTBC genetic epidemiology, recent studies suggest that Single Nucleotide Polymorphisms (SNP) are advantageous in phylogenetics and strain group/lineages identification. In this work we use a set of 79 SNPs to characterize 1987 MTBC isolates from Portugal and 141 from Northeast Brazil. All Brazilian samples were further characterized using spolygotyping. Phylogenetic analysis against a reference set revealed that about 95% of the isolates in both populations are singly attributed to bacterial lineage 4. Within this lineage, the most frequent strain groups in both Portugal and Brazil are LAM, followed by Haarlem and X. Contrary to these groups, strain group T showed a very different prevalence between Portugal (10%) and Brazil (1.5%). Spoligotype identification shows about 10% of mis-matches compared to the use of SNPs and a little more than 1% of strains unidentifiability. The mis-matches are observed in the most represented groups of our sample set (i.e., LAM and Haarlem) in almost the same proportion. Besides being more accurate in identifying strain groups/lineages, SNP-typing can also provide phylogenetic relationships between strain groups/lineages and, thus, indicate cases showing phylogenetic incongruence. Overall, the use of SNP-typing revealed striking similarities between MTBC populations from Portugal and Brazil.
- Socio-demographic factors associated with tobacco consumption and cessation in PortugalPublication . Leite, Andreia; Machado, Ausenda; Dias, Carlos MatiasBackground: Smoking is a significant risk factor for several diseases. Social inequalities have been described for tobacco consumption and though to a lesser extend for tobacco cessation. Objectives: Describe sociodemographic factors associated with tobacco consumption and cessation. Methods: Data from the 2005/2006 Portuguese National Health Interview Survey was analysed. A multinomial log-linear model was fitted considering 3 groups: present smokers, former smokers and never smokers. Relative Risk Ratios (RRR) were obtained. Men and women were analysed separately. RRR adjusted for age and comparatively with reference categories (Centre for regions, married for marital status, student for professional situation and higher education for education) are presented. RRR of present smokers compare to never smokers and RRR of former smokers to present smokers. Results: Men from groups that have higher RRR of present smoking also have lower RRR of stopping. The lowest risk of cessation and higher of consumption was observed in Azores [RRR (95 % Confidence Interval (CI 95)) 0.53 (0.46, 0.61) and 1.89 (1.64, 2.18), respectively]. Divorcees, unemployed, and men with lower secondary education all had lower risk of cessation and higher of consumption, [respectively RRR (IC 95): 0.50 (0.41, 0.61) and 2.01 (1.64, 2.46); RRR (IC 95): 0.16 (0.13, 0.20) and 6.29 (5.00, 7.91); RRR (IC 95): 0.65 (0.56, 0.77) and 1.53 (1.30, 1.79)]. Similar results were observed in women (higher RRR of smoking and lower RRR of stop). Exceptions were found in the non-unemployed women and those with less that upper secondary. Taking region into consideration women in Madeira had a lower RRR of stop smoking and in Lisbon they had the higher risk of smoking [RRR (IC 95) 0.40 (0.27, 0.58) and 2.11 (1.74, 2.57), respectively]. The same was observed for divorced women [RRR (IC 95) 0.54 (0.41, 0.69) and 3.21 (2.69, 3.84), respectively]. Unemployed had the lower risk of quitting smoking and the highest of smoking [RRR (IC 95) 0.83 (0.51, 1.38) and 4.23 (3.20, 5.58), respectively], while the other groups had highest RRR of stop smoking and smoking, comparatively with reference group. Less educated women (lower secondary or less) had lower risk of cessation but also lower risk of smoking. Conclusions: Unfavourable sociodemographic characteristics are associated with higher risks of being a current smoker and lower risks of being an ex-smoker. Different/further cessation measures are needed in these less prone to quit group of individuals, namely men from Azores, divorced, unemployed and with lower secondary education and for divorced and unemployed women.
- Children Exposure assessment to patulin through the intake of apple based productsPublication . Pereira, C.; Alvito, Paula; Martins, Carla; Seljak, B.; Vasco, ElsaNowadays, food safety is of major concern since more chemicals are present in our environment. Food is an important route of exposure to contaminants as mycotoxins. Patulin (PAT) is a mycotoxin present mainly in apple based products which are widely consumed by children. Children are a vulnerable part of the population due to, in part, their physiology, a fairly restricted diet and a higher intake relative to their body weight. Within the safety evaluation procedure of any chemical substance, one crucial step is the dietary exposure assessment. Exposure assessment combines data on concentrations of a chemical substance present in food with the quantity of those foods consumed. Online software to access consumption data are a very useful tool for exposure assessment. The Open Platform for Clinical Nutrition (OPEN) is a Web-based application that provides clinical dietitians and the general population with an online dietary assessment and diet planning tool. It can be used with any food composition dataset that complies with the EuroFIR standards for data harmonisation. In Portugal no data are available on children consumption and data on mycotoxins occurrence in baby foods are scarce. The main objectives of this study were to: i) determine the contents of patulin in apple based foods intended for children, ii) develop tools and procedures for the collection of individual food consumption data for children, iii) test the above mentioned tools and procedures within a pilot dietary survey and iv) analyse the collected data and evaluate the tools and procedures used. For these purposes, 15 samples of apple based foods (juices and purees) analysed for patulin contents (μg/kg) by an accreditated high-performance liquid chromatography and ultraviolet detection method. The children food consumption survey was undertaken using a food diary through the OPEN applied to 20 children aged between 0 to 36 months. Parents were asked to record detailed information about all food and beverages consumed during 3 days. In order to evaluate the exposure, a daily intake will be expressed as μg PAT / kg of body weight / day. For this aim, data on the patulin content will be added to the Portuguese food composition database and applied by the OPEN. We will also consider a provisional tolerable weekly intake (PTWI) of 0.43 μg PAT /kg of body weight / day as a referential value for patulin. Preliminary results of this study shows that apple based products presented patulin contents are all below the legislated limit for patulin (<10 μg/kg). Consumption and exposure assessment results will be discussed. This study reported, for the first time, the use of an online platform for children exposure assessment to patulin through the intake of apple based products in Portugal.
- Genética das hipercolesterolemias dominantesPublication . Bourbon, Mafalda
- The cellular and flagella morphologies of ulcerogenic Helicobacter pylori paediatric strainsPublication . Vitoriano, I.; Saraiva-Pava, K.D.; Matos, A.P.A.; Vale, F.F.; Santos, A.; Lopes, A.I.; Oleastro, M.; Roxo-Rosa, M.Abstract Helicobacter pylori is a pathogenic spiral-shaped, microaerophilic, gram-negative bacterium, that inhabits the human stomach. Infection is usually acquired during childhood and always elicits an acute immune response that is, however, inefficient in bacteria clearance. Therefore, in the absence of effective treatment, infection and gastritis (non ulcer dyspepsia, NUD) persist throughout the patient’s life. Depending on its severity and pattern, in about 15% of infected adults, this silent destruction of the gastric mucosa may further progress to peptic ulcer disease (PUD) (gastric and duodenal ulcers, GU and DU respectively) and/or gastric cancer. Infection with H. pylori is also the major cause for the development of paediatric PUD, a rare event that may occur shortly after infection. In addition to the still undisclosed genetic susceptibility of these young patients, the virulence of the implicated H. pylori strain plays a crucial role in the paediatric PUD pathogenesis. Recently, we proved by in vitro infection assays that, compared with paediatric NUD-associated isolates, a group of paediatric ulcerogenic-strains present a greater ability to induce a marked decrease in the gastric cells viability and to cause them severe cytoskeleton damage and mucins’ production/secretion impairment. Moreover, we showed that their enhanced virulence result from a synergy between the ability to better adapt to the hostility of their niche and the expression of cagA, vacAs1, oipA ‘‘on’’ status, homB and jhp562 virulence factors. Accordingly, these ulcerogenic strains share a particular proteome profile, providing them with better antioxidant defences, a metabolism favouring the biosynthesis of aromatic amino acids and higher motility. We are now characterizing/comparing the cellular and flagella morphologies of H. pylori strains isolated from Portuguese children, associated with DU, GU or NUD, belonging to the vast and multiethnic collection of the Instituto Nacional de Saúde Dr. Ricardo Jorge (Portugal). For that, bacteria were grown in H. pylori selective medium (Biogerm, Maia, Portugal) at 37ºC in a microaerobic environment (Anoxomat®, MART Microbiology BV, Drachten, The Netherlands) for 24 h. For Leifson staining analysis, a drop of each bacterial suspension (in PBS) was spread in cleaned microscope slides, stained with the Leifson dye solution until a golden film developed on the dye surface and a precipitate appeared throughout the sample, and analysed by optical microscopy. For Transmission-Electronic-Microscopy (TEM) studies bacterial pellets were fixed sequentially in glutaraldehyde, osmium tetroxide and uranyl acetate, dehydrated in ethanol and embedded in Epon-Araldite. Thin sections contrasted with uranyl acetate and lead citrate were observed with a JEOL 100-SX electron microscope. Corroborating the better swimming abilities of the PUD strains, as previously shown by motility assays, optical microscopy analysis of Leifson stained slides demonstrated marked differences in the morphology of the studied strains (Figure 1). The H. pylori strain associated with DU (Hp 1152/04) seem longer than all the others and, in contrast, that associated with GU (Hp 499/02) is the shortest one and presents a, more pronounced, spiral morphology. Moreover, our preliminary data on TEM analysis indicate the presence of more abundant and apparently more organized flagella in the GU-associated strain Hp 499/02, in contrast to the NUD control strain, Hp 655/99 (Figure 2).
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