991 resultados para SENSITIVE HALF-TIMES


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The IEEE 802.15.4 Medium Access Control (MAC) protocol is an enabling technology for time sensitive wireless sensor networks thanks to its Guaranteed-Time Slot (GTS) mechanism in the beacon-enabled mode. However, the protocol only supports explicit GTS allocation, i.e. a node allocates a number of time slots in each superframe for exclusive use. The limitation of this explicit GTS allocation is that GTS resources may quickly disappear, since a maximum of seven GTSs can be allocated in each superframe, preventing other nodes to benefit from guaranteed service. Moreover, the GTSs may be only partially used, resulting in wasted bandwidth. To overcome these limitations, this paper proposes i-GAME, an implicit GTS Allocation Mechanism in beacon-enabled IEEE 802.15.4 networks. The allocation is based on implicit GTS allocation requests, taking into account the traffic specifications and the delay requirements of the flows. The i-GAME approach enables the use of a GTS by multiple nodes, while all their (delay, bandwidth) requirements are still satisfied. For that purpose, we propose an admission control algorithm that enables to decide whether to accept a new GTS allocation request or not, based not only on the remaining time slots, but also on the traffic specifications of the flows, their delay requirements and the available bandwidth resources. We show that our proposal improves the bandwidth utilization compared to the explicit allocation used in the IEEE 802.15.4 protocol standard. We also present some practical considerations for the implementation of i-GAME, ensuring backward compatibility with the IEEE 801.5.4 standard with only minor add-ons.

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OBJECTIVE To analyze the temporal evolution of the hospitalization of older adults due to ambulatory care sensitive conditions according to their structure, magnitude and causes. METHODS Cross-sectional study based on data from the Hospital Information System of the Brazilian Unified Health System and from the Primary Care Information System, referring to people aged 60 to 74 years living in the state of Rio de Janeiro, Souhteastern Brazil. The proportion and rate of hospitalizations due to ambulatory care sensitive conditions were calculated, both the global rate and, according to diagnoses, the most prevalent ones. The coverage of the Family Health Strategy and the number of medical consultations attended by older adults in primary care were estimated. To analyze the indicators’ impact on hospitalizations, a linear correlation test was used. RESULTS We found an intense reduction in hospitalizations due to ambulatory care sensitive conditions for all causes and age groups. Heart failure, cerebrovascular diseases and chronic obstructive pulmonary diseases concentrated 50.0% of the hospitalizations. Adults older than 69 years had a higher risk of hospitalization due to one of these causes. We observed a higher risk of hospitalization among men. A negative correlation was found between the hospitalizations and the indicators of access to primary care. CONCLUSIONS Primary healthcare in the state of Rio de Janeiro has been significantly impacting the hospital morbidity of the older population. Studies of hospitalizations due to ambulatory care sensitive conditions can aid the identification of the main causes that are sensitive to the intervention of the health services, in order to indicate which actions are more effective to reduce hospitalizations and to increase the population’s quality of life.

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OBJECTIVE To analyze hospitalization rates and the proportion of deaths due to ambulatory care-sensitive hospitalizations and to characterize them according to coverage by the Family Health Strategy, a primary health care guidance program. METHODS An ecological study comprising 853 municipalities in the state of Minas Gerais, under the purview of 28 regional health care units, was conducted. We used data from the Hospital Information System of the Brazilian Unified Health System. Ambulatory care-sensitive hospitalizations in 2000 and 2010 were compared. Population data were obtained from the demographic censuses. RESULTS The number of ambulatory care-sensitive hospitalizations declined from 20.75/1,000 inhabitants [standard deviation (SD) = 10.42) in 2000 to 14.92/thousand inhabitants (SD = 10.04) in 2010 Heart failure was the most frequent cause in both years. Hospitalizations rates for hypertension, asthma, and diabetes mellitus, decreased, whereas those for angina pectoris, prenatal and birth disorders, kidney and urinary tract infections, and other acute infections increased. Hospitalization durations and the proportion of deaths due to ambulatory care-sensitive hospitalizations increased significantly. CONCLUSIONS Mean hospitalization rates for sensitive conditions were significantly lower in 2010 than in 2000, but no correlation was found with regard to the expansion of the population coverage of the Family Health Strategy. Hospitalization rates and proportion of deaths were different between the various health care regions in the years evaluated, indicating a need to prioritize the primary health care with high efficiency and quality.

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Cork samples from Betula pendula, Quercus suber and Quercus cerris were submitted to Py-GC-MS/FID at temperatures between 550 degrees C and 900 degrees C and the pyrolysis-derived compounds (py-products) were identified and quantified. Corks were compared with wood samples. Py-products include suberin, lignin and carbohydrates derivatives. Suberin py-products are dominated by unsaturated aliphatics. Corks pyrolysis yield and composition were dramatically influenced by temperature in contrast to wood that showed stable results across temperatures. At 850-900 degrees C the peaks area of cork pyrograms were approximately two times higher than at 550 degrees C, for which yield was about half of the woods, and cork py-products were dominated by suberin-derived short chain aliphatics, namely 1-alkenes, while at 550 degrees C composition was dominated by lignin derivatives. Lignin and carbohydrate derived products decreased dramatically over 750 degrees C while the opposite was observed for unsaturated aliphatics. Cork materials show a high potential as feedstock for production of aliphatic-rich pyrolytic biofuels or as a source of olefins. (C) 2014 Elsevier B.V. All rights reserved.

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Nos últimos anos, o avanço da tecnologia e a miniaturização de diversos componentes de electrónica associados a novos conceitos têm permitido nascer novas ideias e projectos, que até há alguns anos não passariam de ficção científica. Talvez o exemplo mais acabado seja actualmente o smartphone, um pequeno bloco de hardware e software, com capacidade de processamento que ultrapassa várias vezes o dos computadores com uma dúzia de anos. Estas capacidades têm sido utilizadas em comunicações, blocos de notas, agendas e até entretenimento. No entanto, podem ser reutilizadas para ajudar a resolver algumas limitações/constrangimentos da actualidade. Dentro destes destacam-se a gestão de recursos escassos. Com efeito, o consumo de energia eléctrica tem aumentado como consequência directa do desenvolvimento global e aumento do número de aparelhos eléctricos. Uma percentagem significativa de energia eléctrica tem sido produzida através de recursos não-renováveis de energia. No entanto, a dependência energética, associada à subida de preços e a redução das emissões de gases do efeito estufa, estimula o desenvolvimento de novas soluções que permitam lidar com esta situação. O desempenho energético por sua vez depende não só das características da estrutura, mas também do comportamento do utilizador. O desempenho energético dos edifícios é muito importante, uma vez que os respectivos consumos são responsáveis por mais de metade do total da energia produzida. Desta forma, a fim de alcançar um melhor desempenho é importante não só considerar o desempenho de estrutura, mas também monitorizar o comportamento do utilizador. Esta última questão coloca várias limitações, uma vez que depende muito do tipo de utilizador. Um dos conceitos actuais emergentes são as chamadas redes de sensores sem fio. Com esta tecnologia, pequenos módulos podem ser desenvolvidos com muitas possibilidades de conectividade, com elevado poder de processamento e com grande autonomia, sem serem excessivamente caros. Isto proporciona os meios para implementar vários dispositivos em toda a instalação, para recolher uma variedade de dados, sendo posteriormente armazenados num servidor. Os blocos fundamentais da infra-estrutura de sensores do projecto foram concebidos na Evoleo Technologies em simultâneo com o decorrer do estágio. Estes blocos recolhem dados específicos na instalação, e periodicamente enviam para o servidor central os valores recolhidos, onde são armazenados e colocados à disposição do utilizador. Os dados recolhidos podem então ser apresentados ao utilizador, proporcionando um registo de consumo de energia associado a um dado período de tempo. Uma vez que todos os dados são armazenados no servidor, podem ser efectuados estudos para determinar o uso típico, possíveis problemas em aparelhos, a qualidade da energia eléctrica, etc., permitindo determinar onde a energia está a ser eventualmente desperdiçada e fornecendo dados ao utilizador para que este possa proceder a alterações, tendo por base dados recolhidos num dado período. O objectivo principal deste trabalho passa por estabelecer a ligação entre o nível máquina e o nível de utilizador, isto é, uma plataforma de interacção entre dispositivos e administrador da instalação. Fornecer os dados de uma forma fácil e sem necessidade de instalação de software específico em cada dispositivo que se pretenda utilizar para monitorizar foi uma das principais preocupações das fases de concepção do projecto.

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Copper iron (Cu-Fe) 3D porous foams for supercapacitor electrodes were electrodeposited in the cathodic regime, on stainless steel current collectors, using hydrogen bubbling dynamic template. The foams were prepared at different current densities and deposition times. The foams were submitted to thermal conditioning at temperatures of 150 and 250 degrees C. The morphology, composition and structure of the formed films were studied by SEM, EDS and XRD, respectively. The electrochemical behaviour was studied by cyclic voltammetry, electrochemical impedance spectroscopy and chronopotentiometry. The morphology of the 3D Cu-Fe foams is sensitive to the electrodeposition current and time. The increase of the current density produces a denser, larger and more ramified dendritic structure. Thermal conditioning at high temperature induces a coarser grain structure and the formation of copper oxides, which affect the electrochemical behaviour. The electrochemical response reveals the presence of various redox peaks assigned to the oxidation and reduction of Cu and Fe oxides and hydroxides in the foams. The specific capacitance of the 3D Cu Fe foams was significantly enhanced by thermal conditioning at 150 degrees C. The highest specific capacitance values attained 297 Fg(-1) which are much above the ones typically observed for single Cu or Fe Oxides and hydroxides. These values highlight a synergistic behaviour resulting from the combination of Cu and Fe in the form of nanostructured metallic foams. Moreover, the capacitance retention observed in an 8000 charge/discharge cycling test was above 66%, stating the good performance of these materials and its enhanced electrochemical response as supercapacitor negative electrodes. (C) 2014 Elsevier B.V. All rights reserved.

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A bi-enzymatic biosensor (LACC–TYR–AuNPs–CS/GPE) for carbamates was prepared in a single step by electrodeposition of a hybrid film onto a graphene doped carbon paste electrode (GPE). Graphene and the gold nanoparticles (AuNPs) were morphologically characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, dynamic light scattering and laser Doppler velocimetry. The electrodeposited hybrid film was composed of laccase (LACC), tyrosinase (TYR) and AuNPs entrapped in a chitosan (CS) polymeric matrix. Experimental parameters, namely graphene redox state, AuNPs:CS ratio, enzymes concentration, pH and inhibition time were evaluated. LACC–TYR–AuNPs–CS/GPE exhibited an improved Michaelis–Menten kinetic constant (26.9 ± 0.5 M) when compared with LACC–AuNPs–CS/GPE (37.8 ± 0.2 M) and TYR–AuNPs–CS/GPE (52.3 ± 0.4 M). Using 4-aminophenol as substrate at pH 5.5, the device presented wide linear ranges, low detection limits (1.68×10− 9 ± 1.18×10− 10 – 2.15×10− 7 ± 3.41×10− 9 M), high accuracy, sensitivity (1.13×106 ± 8.11×104 – 2.19×108 ± 2.51×107 %inhibition M− 1), repeatability (1.2–5.8% RSD), reproducibility (3.2–6.5% RSD) and stability (ca. twenty days) to determine carbaryl, formetanate hydrochloride, propoxur and ziram in citrus fruits based on their inhibitory capacity on the polyphenoloxidases activity. Recoveries at two fortified levels ranged from 93.8 ± 0.3% (lemon) to 97.8 ± 0.3% (orange). Glucose, citric acid and ascorbic acid do not interfere significantly in the electroanalysis. The proposed electroanalytical procedure can be a promising tool for food safety control.

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Dissertação de Mestrado apresentado ao Instituto de Contabilidade e Administração do Porto para a obtenção do grau de Mestre em Auditoria, sob orientação do Mestre Fernando Teixeira Pinto

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RESMO: Introdução: A anemia de células falciformes doença hereditária, com repercussão multi-orgânica, tem grande variabilidade na sua expressão clínica. Daí o interesse do estudo de indicadores de prognóstico. A investigação realizada foi precedida de um resumo histórico incidindo sobre a compreensão de aspectos fundamentais da doença ao longo dos tempos. Na primeira parte do estudo e após revisão bibliográfica, foram referidos dados da fisiopatologia como base para os estudos que integram a presente dissertação. Abordou-se o estado da arte relativamente às complicações, aos indicadores de prognóstico e à terapêutica utilizada. Objectivos: Constituíram objectivos deste estudo realizado numa amostra populacional representativa: identificar as lesões a nível dos sistemas cardio-respiratório e nervoso central, avaliando-se as respectivas repercussões; avaliar a presença de indicadores de prognóstico entre as variáveis seleccionadas; estudar a eficácia e toxicidade da HU nos doentes com as formas graves da ACF. Para a prossecução destes objectivos foram delineados para além do estudo global três estudos específicos: Estudo 1- repercussão no sistema cardio-respiratório; Estudo 2- repercussão no sistema nervoso central; Estudo 3- terapêutica com hidroxiureia. Doentes e métodos: Procedeu-se a um estudo prospectivo e multi-institucional durante um período de três anos tendo-se seleccionado para a amostra, e de acordo com critérios pré-definidos, 30 doentes com ACF na fase estável da doença, com idades compreendidas entre os sete e os 18 anos, todos de origem africana à excepção de um caucasiano. O diagnóstico baseou-se em técnicas de electroforese e estudo molecular que definiu o genotipo da doença e a presença da delecção da -talassémia assim como os haplotipos da amostra populacional. Foram utilizadas diferentes metodologias para avaliar a existência de lesão pulmonar e cerebral. Através do estudo estatístico foram seleccionadas diversas variáveis como hipotéticos indicadores de prognóstico. Estudo 1. Para determinar a existência de lesão a nível pulmonar usaram-se duas metodologias diferentes, a avaliação da função pulmonar com estudo da saturação da Hb em O2 no sangue arterial e a tomografia computadorizada de alta resolução. Estudou-se também a possível disfunção cardíaca como repercussão da lesão pulmonar, através do ecocardiograma, e os indicadores de prognóstico com significado estatístico para a lesão encontrada. Estudo 2. O desenho deste estudo foi sobreponível ao anterior, mas com metodologia adequada para o SNC. Procedeu-se ao estudo das lesões cerebrais por meio de exames imagiológicos, (RMN-CE e DTC) e de testes psicológicos. Correlacionaram-se as três metodologias utilizadas e a importância de cada uma para a decisão de atitudes terapêuticas preventivas. Estudo 3. Consistiu num estudo aberto prospectivo não controlado com nove crianças e adolescentes com formas graves de ACF, com o objectivo de avaliar a eficácia da terapêutica com hidroxiureia, durante um período de 24 meses. Todos os doentes completaram no mínimo 15 meses de terapêutica, com uma dose final média de 194 mg/K/dia. Resultados globais: Durante o período anterior à investigação caracterizou-se a amostra populacional estudada quanto ao fenotipo genético, clínico e hematológico de acordo com os critérios utilizados por outros investigadores. Verificou-se: predomínio do haplotipo Bantu na forma homozigótica em 53% dos doentes; número total de EVO ≥3/ano em 87,5% dos doentes; crises de sequestração em 18,75%; dactilites no primeiro ano de vida em 31,2%; quadro de sépsis grave apenas num doente; crises de hiper-hemólise em 50%; e STA em 59,38% dos doentes. Quanto ao fenotipo hematológico evidenciaram-se como factores de risco reticulocitose (13,1x103/l) e hiperbilirrubinémia (2,5 mg/dl) e como factores de bom prognóstico a presença de delecção de um gene da -talassémia em 46,9% dos doentes e valor médio de Hb 8,1 g/dl. Resultados dos estudos parcelares: Estudo 1. Deste estudo infere-se que a DPR ligeira foi diagnosticada em 70% dos doentes, uma vez que as alterações da difusão não foram estatisticamente significativas, o estudo dos gases no sangue não evidenciaram resultados anormais e a TCAR evidenciou alterações em 43,3% dos doentes. Apenas num doente se verificou doença pulmonar obstrutiva relacionada com maior número da STA.O estudo da disfunção cardíaca encontrada em 86,7% dos doentes não reflecte a repercussão da DPR a nível cardíaco, podendo estar associada às alterações fisiopatológicas da própria anemia crónica. Encontraram-se indicadores de prognóstico hematológicos e clínicos. Entre os primeiros, valores de Hb ≥8,5 g/dl e de HbF ≥13% foram considerados indicadores de bom prognóstico para a lesão pulmonar. Em relação aos parâmetros clínicos, as STA não foram consideradas indicadoras de prognóstico para a DPR ao contrário do que se verificou com o número de EVO. Pela análise dos parâmetros genéticos e socio-económicos provou-se a ausência de relação estatisticamente significativa com lesão pulmonar. Estudo 2. Pela RMN-CE foram diagnosticados ES em 33,3% com uma localização preferencial na substância branca profunda em 26,6% dos doentes. Relativamente aos parâmetros hematológicos seleccionados, o valor médio da HbF 8,6% constituíu um indicador de bom prognóstico para o aparecimento de ES, enquanto o valor médio de leucócitos 12.39x103/μl foi considerado um indicador de mau prognóstico. No estudo do DTC apenas um doente apresentou aumento da velocidade do fluxo cerebral na ACM igual a 196 cm/segundos, associado a vasculopatia grave. Os testes psicológicos alterados em 80% dos doentes mostraram ser o método mais sensível para detectar alterações do neurodesenvolvimento, mas sem correlação com os ES em 10% dos doentes. Realça-se a baixa percentagem de DTC patológicos encontrados neste estudo em relação ao número elevado de ES e de testes psicológicos alterados, não se verificando concordância entre os três exames. Dos indicadores de prognóstico estudados a -talassémia foi considerada um factor de protecção para o coeficiente de inteligência da escala de Wechsler. Em relação a parâmetros clínicos estudados os doentes com maior número de EVO, tem em média valores inferiores nos testes psicológicos. Estudo 3. Neste estudo verificou-se que o valor médio da HbF aumentou significativamente de 7,0±4% para 13,7±5,3% (p=0,028) ao fim de 15 meses de terapêutica com hidroxiureia. Clinicamente todos os doentes responderam significativamente com uma redução de 80% no número de EVO, 69% no número de internamentos, 76% no número de dias de hospitalização e 67% no número de transfusões. Deste modo comprovou-se não só a eficácia desta terapêutica neste grupo pediátrico como também a falta de efeitos secundários significativos. Considera-se a necessidade de estudos mais prolongados e em grande séries, para com segurança se usar a HU antes que a lesão orgânica se estabeleça, portanto logo nos primeiros anos de vida. Conclusão: Na amostra populacional estudada foram evidenciadas lesões pulmonares e cerebrais na grande maioria dos doentes que condicionaram a sua qualidade de vida. Foram identificados indicadores de prognóstico que poderão eventualmente ditar medidas terapêuticas precoces com o objectivo de diminuir a morbilidade e a mortalidade neste grupo etário. Demonstrou-se que a terapêutica com a HU foi eficaz e bem tolerada----------ABSTRACT: Background: Sickle cell anemia (SCA), a hereditary disease characterized by pain and lifetime multi-organic lesion, is a challenge for all that work with carriers of this disease. The clinical expression variability of SCA is a constant reality and a problem to be solved in the current world of investigation, for which the knowledge of prognostic indicators responsible for the different aspects of clinical evolution diversity wiil be an added value. The study is preceded by a historical summary of the most important factors in the evolution of SCA, which are in themselves, an incentive for future research. In the first part of the study, after an extensive bibliographical revision, physiopathology data is referred to in general and specifically regarding the target organs, that constituted the base for the studies presented in the dissertation. The state of the art for the complications to be studied, the choice of prognostic indicators and the therapeutics application, were approached for the renewed interest in the theme. Aims: In regard to the investigation, the objective was to study the lesions in the most affected organs of a chosen pediatric group, to investigate prognostic indicators for lung and cerebral lesions and to evaluate the protective effect of hydroxyurea in children with severe outcomes. Patients and methods: A prospective and multi-institutional study was carried out during a three-year period, February 1998 to March 2001, with children and adolescents followed up at a Immunohematology Outpatient Clinic of Dona Estefânia's Hospital, Lisbon. Based in predefined criteria, 30 children with SCA were selected in a stable phase of the disease, aged from seven to 18 years old, all of whom were of African origin with exception of one who was Caucasian. The diagnosis was based on electrophoresis techniques and molecular study that allowed to define the genotype, the presence of deletional alpha-thalassemia as well as haplotypes in the population. Different methodologies were used to evaluate the existence of lung and cerebral lesion. Statistical study of the different variables selected the prognostic indicators. In Study 1, to determine the existence of lung lesion two different methodologies were used: pulmonar function study with arterial blood gases determination; and high resolution computerized tomography. Heart dysfunction as a repercussion of lung lesion was also studied through echocardiography, and prognostic indicators were statistically significant for lesions found. The design of Study 2 was similar to Study 1, but with the appropriate methodology for CNS. After neurological examination, which was normal in all patients (control group), cerebral lesions were studied with imagiologic exams (MRN-CE and TCD) and psychological tests. These three methodologies were correlated and the importance of each one in the decision of the therapeutic profilactic attitudes. Study 3 consisted of a controlled prospective open study in children with severe forms of SCA, with the aim of the evaluating therapeutic effectiveness of hydroxyurea, during a period of 24 months. Results: In the global overall study preceding the Studies 1,2 and 3, there were a prevalence of haplotype Bantu (53%) and other risk factors, namely the number of VOC (87,5%), sequestration crisis (18,75%), dactilytis in first year of life(31,2%), hyperhemolysis crisis (50%) and ATC in more than half of the patients (59,38%). This group of bad prognostic indicators, associated with the population of the lower class according to the Graffar scale, demonstrates the importance of primary health care services, information provided to the children and their relatives, as well as the interest in prophylactic therapeutics, specific screening and prenatal diagnosis. Study 1. It was evident from this study that slight RPD was diagnosed in 70% of the patients, because alterations of the diffusion had no statistical significance and arterial blood gases determinations were normal. Only one patient had restrictive lung disease related with numerous ACS. However ACS was not considered a prognostic indicator for RPD, contrary to the number of EVO. HRTC revealed discreet fibrotic lines that could be related with slight RPD, but the lack of correlation of these two exams (33%) supports the value of lung function tests for precocious diagnosis of RPD. Heart dysfunction was found in 86,7% of patients, does not reflect the repercussion of RPD, but with the physiopathology of chronic anemia. Hematologic and clinical prognostic indicators were found. Good prognostic indicators for the non-evolution of RPD with average Hb values of ≥ 8,5 g/dl and average HbF values of ≥13%, respectively. The genetic and social-economic factors had no statistical significance; nevertheless, they were more prevalent among Bantu haplotype (53,3%) in patients with RPD. Study 2. RMN-CE detected SI in 33,3% of the patients, with preferential location in deep white substance in 26,6% and in front lobe in 20%. This distribution can be related to structural aspects of the brain and with the high sensibility of this organ to hypoxia. From the hematological parameters selected, average HbF value 8,6% and average leucocyte count 12.39x103/μl were prognostic indicators with different meaning to SI. The increase in the total bilirubin related to hyperhemolysis clinically explains the genesis of SI In the TCD study, only one patient had increased cerebral flow speed >196 cm/sec in CMA, which corresponded to serious vasculopathy in AngioMR. This patient never present previously neurological symptoms and had several hyperhemolysis crisis and VOC as risk factors. Low percentage of pathological TCD in this study, in relation to the high number of SI and altered tests, although without correlation among the three exams, is probably attributed to factors related to the methodology, aspects of cerebral physiopathology or perhaps a sign of good prognostic if the duration of study had not been so short. TCD should be used as a screening method in the age groups with higher risk of AVC and should never be considered separately in prophylactic therapeutics indication. Psychological tests were the most sensitive method to detect neurodevelopment impairment; in 80% of patients the neuropsychologics tests were altered, but without correlation with SI (10%). Since SI can become evident during the first two years of life and develop with time, the first psychological tests should be carried out between 3 and 5 years of age to timely be referred to special education and stimulation programs. Prognostic indicators to psychological tests were also found: alpha-thalassemia was found to be a protection factor of the IQ, just as other hematologic factors (hematocrit, MGCV and erythrocytes count). In relation to clinical parameters, although without statistical significance, patients with larger number of VOC had average lower scores versus the average in tests, except in TP. Results from different studies were conclusive as to the type of lesion found and the importance of prognostic indicators. Study 3. All the patients completed a minimum of 15 months therapeutic treatment with the final average daily dose of 19±4 mg/kg/day. The average value of the fetal hemoglobin increased significantly from 7,0±3,9% to 13,7±5,3% (p=0.028). The HbF average values increased from 6% to 15% after 15 months of therapeutic treatment. Clinically there was a reduction of 80% in the number of VOE , 69% in the number of hospitalization, 76% in the number of days of hospitalization and 67% in the number of transfusions. Once again the effectiveness of this treatment in this pediatric group, as well as the lack of any significant secondary effects, was evident. The study confirms the need for further detailed research in order to safely effect the appropriate treatment prior to the development of organic lesions, which ideally should be in the first year of life. Conclusions: These results allow us to clarify the importance of either pulmonary lesions or either nervous central system impairment among patients, children and adolescents, with sickle cell anemia. These lesions were demonstrated in most of the patients studied compromising their quality of life and the mortality. The treatment with HU is proved to be effective and having low toxicity.

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6th Graduate Student Symposium on Molecular Imprinting

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Chemical sensors and biosensors are widely used to detect various kinds of protein target biomolecules. Molecularly Imprinted Polymers (MIPs) have raised great interest in this area, because these act as antibody-like recognition materials, with high affinity to the template molecule. Compared to natural antibodies, these are also of lower cost and higher stability. There are different types of supports used to carry MIP materials, mostly of these made of gold, favourably assembled on a Screen Printed Electrode (SPE) strategy. For this work a new kind of support for the sensing layer was developed: conductive paper. This support was made by modifying first cellulose paper with paraffin wax (to make it waterproof), and casting a carbon-ink on it afterwards, to turn it conductive. The SPAM approach previously reported in1 was employed herein to assemble to MIP sensing material on the conductive paper. The selected charged monomers were (vinylbenzyl) trimethlammonium chloride (positive charge) or vinylbenzoic acid (negative charge), used to generate binding positions with single-type charge (positive or negative). The non-specific binding area of the MIP layer was assembled by chronoamperometry-assisted polymerization (at 1 V, for 60, 120 or 180 seconds) of vinylbenzoate, cross-linked with ethylene glycol vinyl ether. The BSA biomolecules lying within the polymeric matrix were removed by Proteinase K action. All preparation stages of the MIP assembly were followed by FTIR, Raman spectroscopy and, electrochemical analysis. In general, the best results were obtained for longer polymerization times and positively charged binding sites (which was consistent with a negatively-charged protein under physiological pH, as BSA). Linear responses against BSA concentration ranged from 0.005 to 100 mg/mL, in PBS buffer standard solutions. The sensor was further calibrated in standard solutions that were prepared in synthetic or real urine, and the analytical response became more sensitive and stable. Compared to the literature, the detection capability of the developed device is better than most of the reported electrodes. Overall, the simplicity, low cost and good analytical performance of the BSA SPE device, prepared with positively charged binding positions, seems a suitable approach for practical application in clinical context. Further studies with real samples are required, as well as gathering with electronic-supporting devices to allow on-site readings.

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We evaluated the immunogenicity of three recombinant hepatitis B vaccines, one Brazilian (Butang, Instituto Butantan) and two Korean vaccines (Euvax-B, LG Chemical Ltd. and Hepavax-Gene, Greencross Vaccine Corp.), administered intramuscularly to students aged 17 to 19 years in three 10-µg doses (corresponding to half the amount of antigen routinely used for adult vaccination) at intervals of one month between the first and second dose, and of four months between the second and third dose. A total of 316 students non-reactive for any serological marker of hepatitis B virus infection were vaccinated: 77 (24.4%) with the Butang vaccine, 71 (22.5%) with Euvax-B, 85 (26.9%) with Hepavax-Gene and, for comparison, 83 (26.2%) with Engerix-B (GlaxoSmithKline), whose efficacy in young adults at the dose used here has been confirmed in previous studies. Similar seroconversion rates (anti-HBs > 10 mIU/mL about one month after application of the third dose) were obtained for the Butang, Euvax-B, Hepavax-Gene and Engerix-B vaccines (96.2%, 98.6%, 96.5% and 97.6%, respectively). The frequency of good responders (anti-HBs > 100 mIU/mL) was also similar among students receiving the four vaccines (85.8%, 91.6%, 89.4% and 89.2%, respectively). The geometric mean titers (GMT) of anti-HBs about one month after the third dose obtained with these vaccines were 727.78 ± 6.46 mIU/mL, 2009.09 ± 7.16 mIU/mL, 1729.82 ± 8.85 mIU/mL and 2070.14 ± 11.69 mIU/mL, respectively. The GMT of anti-HBs induced by the Euvax-B and Engerix-B vaccines were higher than those obtained with the Butang vaccine (p < 0.05); this difference was not significant when comparing the other vaccines two-by-two. No spontaneous adverse effects attributable to the application of any dose of the four vaccines were reported.

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Cavopulmonary connections have been extensively used in the palliation of complex forms of congenital heart disease requiring some form of right heart bypass. We examine the mid term outcomes of pulmonary ventricle bypass operations in a single institution and performed by the same surgical team. POPULATION: Between March 1999 and April 2006, 62 patients underwent pulmonary ventricle bypass operations: bidirectional cavopulmonary anastomosis (Glenn procedure), total cavopulmonary connections (Fontan procedure) and one and a half ventricle correction in two cases. Age at operation averaged three years (range: 0.42-25 years) for the Glenn procedure and seven years (range: 3-14 years) for the Fontan procedure. There were 36 male patients (58%) and 26 female patients (42%). The most common indication for surgery was the single ventricle defect, present in 66% of patients. Associated lesions included: transposition of the great arteries in 16 patients (35.6%), bilateral superior vena cava in four patients (8.9%), situs ambigus in five patients (11%), situs inversus in another patient (2.2%), Ebstein disease in one patient (2.2) and coronary fistula in another patient (2.2%). Sub-aortic stenosis was present in one patient (2.2%). Palliative surgery was performed in all, but three patients (5%), before the Fontan procedure. RESULTS: Thirty two patients underwent bidirectional cavopulmonary anastomosis and thirty patients underwent cavopulmonary connections, total or 2nd stage. Mean cardiopulmonary bypass times were 50.6+/-21.9 minutes for the Glenn procedure and 88.5+/-26.3 minutes for the Fontan procedure. There was no intra-operative mortality, but two patients (3.2% (died in the first month after surgery; one due to failure of the Glenn circuit and sepsis and the other due to a low cardiac output syndrome and multi-organ dysfunction. Mean ventilation time was 5.2+/-1.7 hours for the Glenn operation and 6.2+/-3.2 hours for the Fontan operation. The mean length of stay in ICU was 3.4+/-2.8 days for patients undergoing the Glenn operation and 4.6+/-3.1 days for patients undergoing the Fontan operation and the mean length of hospital stay was 10.6+/-5.8 days for the Glenn operation and 19.1+/-12.6 days for the Fontan operation respectively. The mean follow up time was 4+/-2.1 years (minimum 0 years and maximum seven years), most patients being in NYHA class I. Epicardiac pacemakers were implanted in three patients due to arrhythmias. Two re-operations (6.7%) were needed, both in the same patient, after the Fontan procedure, this patient eventually died a few years after surgery. CONCLUSIONS: The immediate and mid term outcomes of pulmonary ventricle bypass operations can have excellent results. From our point of view there has been an improvement, namely in the use of the extracardiac conduit technique in the 2nd stage of the Fontan operation.

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Herpes simplex virus type 1 (HSV-1) ophthalmic disease is the most common cause of corneal blindness in humans world-wide. Current culture techniques for HSV take several days and commercially available HSV laboratory based diagnostic techniques vary in sensitivity. Our study was conducted to evaluate the use of a quicker and simpler method to herpes ophthalmic diagnosis. Corneal smears were made by firm imprints of infected mouse eyes to glass slides, after smears were fixated with cold acetone, and an indirect immunofluorescence (IIF) method was performed using monoclonal antibodies in a murine model of ophthalmic herpes. Eye swabs from infected mice were inoculated in Vero cells for virus isolation. Cytology and histology of the eye were also performed, using hematoxylin-eosin routine. Mouse eyes were examined by slit-lamp biomicroscopy for evidence of herpetic disease at various times postinoculation. We made a comparative evaluation of sensitivity, specificity and speed of methods for laboratory detection of HSV. Our results indicate that this IIF method is quick, sensitive, specific and can be useful in the diagnosis of ophthalmic herpes as demonstrated in an animal model.