Percorrer por autor "Carvalho, A."
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- Contaminação de água subterrânea por substâncias de limpeza da neve em estradas: o caso do sector de Nave de Santo António – Covão do Curral (Serra da Estrela, Centro de Portugal)Publication . Carvalho, A.; Espinha Marques, J.; Marques, J.M.; Carreira, P.M.; Moura, R.; Guerner Dias, A.; Chaminé, H.I.; Rocha, F.; Saraiva, R.; Tavares, M.; Mansilha, C.Num momento em que a gestão sustentável dos recursos hídricos se assume como uma das maiores preocupações à escala mundial, as regiões de montanha têm vindo a ser reconhecidas como Reservatórios de Água (PROGRAMA UNESCO IHP-VI). O facto de muitas destas áreas se localizarem a altitudes elevadas e serem recortadas por rodovias obriga a frequentes operações de limpeza de neve, especialmente no inverno. A aplicação de substâncias químicas como cloreto de sódio e cloreto de cálcio na promoção da fusão do gelo e na limpeza da neve das estradas constitui um problema ambiental de elevado interesse científico, social e económico. Devido às suas características geológicas, geomorfológicas e climáticas, a Serra da Estrela é considerada estratégica para a gestão da água em Portugal. No presente trabalho apresentam-se alguns resultados hidrogeoquímicos que indicam que a utilização dos referidos sais na limpeza do gelo e da neve das rodovias contribui para a contaminação dos recursos hídricos.
- Doença de arranhadela do gato em mulher de 44 anos de idadePublication . Murinello, Natacha; Murinello, N.; Murinello, A.; Damásio, H.; Carvalho, A.; de Sousa, R.A doença da arranhadela do gato é uma zoonose causada pela bactéria Bartonella henselae, e transmitida ao homem por inoculação em lesões de arranhadelas ou mordeduras de gatos. Descreve-se aqui um caso de doença da arranhadela do gato numa mulher de 44 anos de idade, imunocompetente, que se apresentou com uma pápula/crosta num dedo da mão direita, linfadenopatias regionais e foi tratada com azitromicina por apresentar uma linfadenopatia epitroclear muito dolorosa. O diagnóstico de infecção por B. henselae foi confirmado laboratorialmente por serologia, e PCR (polymerase chain reaction) numa biópsia de gânglio axilar. Foi também detectado DNA de B. henselae no sangue do gato da doente, mas não nas quatro pulgas, Ctenocephalides felis que parasitavam o gato. Importantes métodos de diagnóstico como a técnica de PCR e sequenciação permitem caracterizar a espécie ou estirpe responsáveis pela infecção no homem uma vez que actualmente existem novas espécies de Bartonella emergentes a causar a mesma doença. Para além disso é extremamente importante para a epidemiologia das doenças existentes no nosso país saber quais as espécies que circulam e que podem causar doença no homem.
- Eficácia da suplementação de vitamina A em crianças da República Democrática de São Tomé e PríncipePublication . Valente, A.; Albuquerque, T.G.; Carvalho, A.; Costa, H.S.Introdução: A República Democrática de São Tomé e Príncipe é um país subdesenvolvido com indicadores de saúde preocupantes no que se refere à taxa de mortalidade infantil, especialmente em crianças de idades pré-escolares. Segundo os dados da United Nations Children's Fund (UNICEF), em 2009 a taxa de mortalidade foi ainda de 37,1%, sendo a malnutrição uma das principais causas de morte infantil, neste País. A deficiência de vitamina A é uma das carências nutricionais mais prevalentes no Mundo subdesenvolvido, apresentando-se como um problema de Saúde Pública em mais de 70 países. De acordo com os critérios da World Health Organization e da UNICEF, a deficiência em vitamina A é considerado um grave problema de Saúde Pública, quando a prevalência de hipovitaminose A (<0,70 μmol/L ou 200 μg/L) é igual ou maior a 20%. Objectivos: Este trabalho teve como objectivo dosear e avaliar os níveis séricos de retinol em crianças da República Democrática de São Tomé e Príncipe antes e após um período de suplementação. Métodos: A população em estudo é constituída por 212 crianças com idades compreendidas entre o 1 e os 5 anos, de dois (Água Grande e Mé-Zochi) dos sete distritos administrativos da República Democrática de São Tomé e Príncipe. Os níveis séricos de retinol nos participantes do estudo foram determinados por cromatografia líquida de elevada resolução. Resultados: Os resultados obtidos indicam que no período de pré-suplementação cerca de 37% das crianças participantes no estudo tinham hipovitaminose A severa (retinol sérico: <100 μg/L), e no período pós-suplementação esse valor passou para 2%. Verificou-se também uma redução na percentagem de participantes com hipovitaminose A moderada (retinol sérico: 100-200 μg/L), que passou de 59% para cerca de 15%. A percentagem de crianças que inicialmente tinham valores séricos de retinol normais (≥200 μg/L) era de 4,4% e após o período de suplementação, essa percentagem passou para 83,5%, o que significa um aumento de cerca de 79%. Em termos globais, cerca de 16,5% das crianças continuam a ter hipovitaminose A e 83,5% passaram a ter níveis normais de retinol sérico, dos quais 29,7% têm entre 200-300 μg/L, 31,1% entre 300-400 μg/L e em 22,7% dos casos os valores séricos de retinol são superiores a 400 μg/L. Conclusões: A eficácia da suplementação com vitamina A nas crianças da República Democrática de São Tomé e Príncipe foi comprovada pela redução da prevalência de hipovitaminose A em cerca de 79,1%.
- Estrogen Metabolism-Associated CYP2D6 and IL6-174G/C Polymorphisms in Schistosoma haematobium InfectionPublication . Cardoso, R.; Lacerda, P.C.; Costa, P.P.; Machado, A.; Carvalho, A.; Bordalo, A.; Fernandes, R.; Soares, R.; Richter, J.; Alves, H.; Botelho, M.C.Schistosoma haematobium is a human blood fluke causing a chronic infection called urogenital schistosomiasis. Squamous cell carcinoma of the urinary bladder (SCC) constitutes chronic sequelae of this infection, and S. haematobium infection is accounted as a risk factor for this type of cancer. This infection is considered a neglected tropical disease and is endemic in numerous countries in Africa and the Middle East. Schistosome eggs produce catechol-estrogens. These estrogenic molecules are metabolized to active quinones that induce modifications in DNA. The cytochrome P450 (CYP) enzymes are a superfamily of mono-oxygenases involved in estrogen biosynthesis and metabolism, the generation of DNA damaging procarcinogens, and the response to anti-estrogen therapies. IL6 Interleukin-6 (IL-6) is a pleiotropic cytokine expressed in various tissues. This cytokine is largely expressed in the female urogenital tract as well as reproductive organs. Very high or very low levels of IL-6 are associated with estrogen metabolism imbalance. In the present study, we investigated the polymorphic variants in the CYP2D6 gene and the C-174G promoter polymorphism of the IL-6 gene on S. haematobium-infected children patients from Guine Bissau. CYP2D6 inactivated alleles (28.5%) and IL6G-174C (13.3%) variants were frequent in S. haematobium-infected patients when compared to previously studied healthy populations (4.5% and 0.05%, respectively). Here we discuss our recent findings on these polymorphisms and whether they can be predictive markers of schistosome infection and/or represent potential biomarkers for urogenital schistosomiasis associated bladder cancer and infertility.
- Hepatic steatosis in an adult population: stronger correlation with the presence of obesity and insulin resistence than with the dietary pattern: results from a cross-sectional studyPublication . Leitao, J.A.M.C.P.; Cochicho, J.; Carvalhana, S.; Velasco, F.; Silva, A.P.; Medeiros, I.S.; Alves, A.C.; Bourbon, M.; Oliveiros, B.; Rodrigues, V.; Carvalho, A.; Cortez-Pinto, H.Background and Aims: Hepatic steatosis is very frequent in thegeneral population, mostly associated with obesity and insulinresistance. Typical dietary patterns have been difficult to identifywith controversial information. We aimed to estimate in a represen-tative sample of the Portuguese adult population, what was thecontribution of the dietary pattern in what concerns macronutrientsand food groups for the presence of steatosis as well as the othertraditional risk factors for steatosis.
- Improving influenza surveillance in Portuguese preschool children by parents' reportPublication . Paixão, P.; Piedade, C.; Papoila, A.; Caires, I.; Pedro, C.; Santos, M.; Silvestre, M.J.; Brum, L.; Nunes, Baltazar; Guiomar, R.; Curran, M.D.; Carvalho, A.; Marques, T.; Neuparth, N.Influenza surveillance is usually based on nationally organized sentinel networks of physicians and on hospital reports. This study aimed to test a different report system, based on parents’ phone contact to the research team and in home collection of samples by a dedicated team. The identification of influenza and other respiratory viruses in children who attended a Hospital Emergency Department was also recorded. Real-time PCR and reverse transcription PCR were performed for influenza A and B, parainfluenza 1-4, adenovirus, human metapneumovirus, respiratory syncytial virus A and B, rhinovirus, enterovirus, group 1 coronaviruses, group 2 coronaviruses, and human bocavirus. One hundred children were included, 64 from the day care centers and 36 from the Hospital. Overall, 79 samples were positive for at least one respiratory virus. Influenza A (H3) was the virus most frequently detected: 25 cases, 20 of these in children under 5 years of age (ten from day care centers and ten who went to the hospital) which was higher than those reported by the National Influenza Surveillance Programme for this age. Conclusion: The results obtained in this study suggest that a surveillance system based on parents’ reports could complement the implanted system of the National Influenza Surveillance Programme.
- Prevalence of alcoholic steatosis in the general adult Portuguese populationPublication . Leitao, J.A.M.C.P.; Carvalhana, S.; Cochicho, J.; Silva, A.P.; Velasco, F.; Medeiros, I.S.; Alves, A.C.; Bourbon, M.; Oliveiros, B.; Rodrigues, V.; Carvalho, A.; Cortez-Pinto, H.Background and Aims: Fatty liver is very frequent in the general population. Although many studies evaluated the prevalence of nonalcoholic fatty liver disease there is scarce information regarding alcoholic fatty liver. We aimed to estimate the prevalence of alcoholic hepatic steatosis, and to what extent it depended on obesity and its interaction.
- Schistosoma haematobium in Guinea-Bissau: unacknowledged morbidity due to a particularly neglected parasite in a particularly neglected countryPublication . Botelho, M.C.; Machado, A.; Carvalho, A.; Vilaça, M.; Conceição, O.; Rosa, F.; Alves, H.; Richter, J.; Bordalo, A.A.Schistosomiasis is the major neglected tropical helminthic disease worldwide. Current knowledge on the epidemiology of schistosomiasis in Guinea-Bissau is scarce and regarding to the absence of Schistosoma haematobium (S.h.). Therefore, a pilot study was undertaken to assess the prevalence and morbidity due to S.h. infection in randomly selected 90 children and adolescents aged 6 to 15 years. Prevalence of S.h. infection was 20.00 % (18/90). Microhematuria was observed in 61.11 % (11/18) of S.h.-egg-excreting vs. 37.50 % (27/72) of non-S.h.-egg-excreting children p ≤ 0.01. Body mass index (BMI) was less than 15 kg/m(2) in 52/90 (57.78 %) of all children and adolescents, but this proportion increased to 66.67 % (12/18) in S.h.-infected children who were more frequently stunted and wasted than in non-infected children. The mean weight-for-age Z score (WAZ) was reduced in S.h. infected as compared to non-infected children (-1.48 ± 1.08 SD vs. -0.80 ± 1.11 SD; p ≤ 0.01). To our knowledge, this is the first epidemiologic report on S. haematobium infection in Guinea-Bissau since 22 years. Even in this relatively small study sample, it appears that S. haematobium, besides the well-known symptoms such as hematuria, leads to significant, albeit commonly unacknowledged morbidity such as stunting and wasting. These observations underscore the notion that this vulnerable but neglected population urgently needs to be targeted for implementation of measures for treatment and control.
- Tuberculosis in a child - search for the infected adult nearby; case report, Portugal, 2007Publication . Duarte, R.; Tavares, E.; Miranda, A.; Carvalho, A.Tuberculosis (TB) transmission in a non-household setting is difficult to detect, because contact with the source case is often not obvious. Here, we report on a case of a four-year-old child who got infected through sporadic non-household exposure at a coffee shop. The source case was a woman who had suffered from weight loss, productive cough and fatigue for two months before being diagnosed with TB. Screening the child s contacts revealed two active TB cases within its family. Overall 148 contacts were screened for both cases and 18 cases of latent TB infection detected. The connection between the child and the source case, who were not aware of their contact, was confirmed by molecular fingerprinting. Our case report illustrates the difficulty in detecting non-household transmission between individuals that do not have significant contact, and draws attention to the need to look for the infected adult whenever a child falls ill with TB. This report is a reminder of the importance to consider possibly neglected ways of TB transmission and highlights once again the need of early diagnosis of TB.
- Tuberculosis in a shopping centre, Portugal, 2004-5Publication . Duarte, R.; Miranda, A.; Braga, R.; Carvalho, A.; Rola, J.; Marques, A.; Barros, H.Genotyping enables to confirm or exclude a tuberculosis (TB) cluster. Excluding the link between cases is particularly important in countries with intermediate/high incidence of TB where the emergence of several TB cases in a particular location in space or time (higher than the expected) could be explained by chance alone. During 2004 and 2005, five TB cases occurred in five shops of a Portuguese shopping centre which employed a total of about 1000 workers. After an epidemiological survey, 52 close contacts were identified and screened. Latent tuberculosis infection was diagnosed in 10 contacts (eight family members and two work colleagues of cases). Genotyping of the Mycobacterium tuberculosis isolates revealed no link between the cases. For this reason no screening of all staff of the shopping centre was carried out. However, close contacts (52) and all fellow workers (1000) were kept under surveillance for two years, and no additional cases were diagnosed. The present analysis demonstrates that the exclusion of a chain of ongoing transmission by genotyping for the investigation of a cluster is cost-effective from the perspective of the public health service, because it allows to avoid unnecessary large scale screening operation and instead to direct resources to more effective measures of TB control.