[The Importance of Early Referral in Pediatric Acute Liver Failure]

INTRODUCTION: Acute liver failure is a rare disorder associated to high morbidity and mortality despite survival improvement through liver transplantation. The importance of a multidisciplinary approach and early referral to a pediatric liver transplantation center were important conclusions of a national meeting in 2008, from which resulted an actuation consensus. OBJECTIVES: To characterize acute liver failure admissions in a Pediatric Intensive Care Unit of the portuguese pediatric livertransplantation center. To compare results before (A) and after (B) 2008. MATERIAL AND METHODS: Observational, retrospective study during a 20 year period (1994-2014). INCLUSION CRITERIA: age < 18 years old and acute liver failure (INR ≥ 2 without vitamin K response and hepatocellular necrosis). Children with previous liver disease were excluded. RESULTS: Fifty children were included, with median age of 24.5 months. The most common etiology under 2 years old was metabolic (34.6%) and above that age was infectious (29.2%). Forty six percent were submitted to liver transplantation and 78% of them survived. Overall mortality was 34%. Median referral time was 7 days in period A (n = 35) and 2 days in period B (n = 15; p = 0.006). Pediatric risk of mortality's median was 14.7 in period A and 6.5 in B (p = 0.019). Mortality was 37% vs 26% in periods A and B, respectively (p = 0.474). DISCUSSION AND CONCLUSIONS: Overall mortality was similar to the observed in other European centers. Liver transplantation is in fact the most effective therapeutic option. After 2008, there was a reduction in referral time and cases severity on admission; however, mortality has not reduced so far.info:eu-repo/semantics/publishedVersio

Utilização da técnica de espectrofotometria do infravermelho próximo (NIR) para análise discriminante dos ácidos graxos oléico e linoléico de genótipos de girassol.

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Características dos sistemas de produção de ovinos e caprinos no nordeste paraense.

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Análises moleculares de bactérias e fungo em cana-de-açúcar.

RESUMO: A cana-de-açúcar é uma das principais culturas do Brasil, que é o maior produtor mundial de açúcar e álcool. A cultura da cana-de-açucar é extremamente vulnerável a doenças devido ao sistema de propagação por toletes facilitar a disseminação dos patógenos, uma vez que os colmos mesmo infectados podem não apresentar sintomas. A propagação dessas doenças em monoculturas em grandes áreas facilita as epidemias, sendo importante para o plantio de mudas sadias, métodos para a detecção precoce de doenças. Dentre as doenças mais importantes em cana-de-açúcar, são conhecidas as causadas por bactérias como a Leifsonia xyli subsp.xyli, agente causal do Raquitismo-da-soqueira ou ?ratoon stunting disease? (RSD) e a Xanthomonas albilineans, responsável pela Escaldadura das folhas ou ?sugarcarne leaf scald? (Ashby); por fungo como o do carvão (Ustilago scitaminea) que é uma doença considerada em todos os programas de melhoramento genético, com longo período de latência. Foram utilizadas como amostras folhas de plântulas de cana-açúcar desenvolvidas de cultura de tecido com cerca de 2 meses de transplante. Foram utilizados iniciadores de literatura para raquitismo e escaldadura ou desenvolvido pelo laboratório para carvão. Os fragmentos amplificados de cada doença foram clonados e a identidade confirmada por BLAST. O DNA dos controles positivos das reações foi obtido de clones dos fragmentos amplificados de plantas infectadas. Os iniciadores desenvolvidos para carvão mostraram especificidade em amostras de folhas de plântulas de cana-de-açúcar. A detecção de infecção confirma a eficácia da metodologia em plântulas com 2 meses de transplante, assim como o uso de clones como controle positivo, a maior facilidade para diagnostico de infecção em plântulas de cana-de-açúcar

Características dos sistemas de produção de gado de corte na região bragantina.

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Simple strategies for stable aqueous suspensions of carbon nanotubes

Carbon nanotubes (CNT) are attractive nanoparticles for biological applications due to their broad absorption of light in the UV-Vis-NIR, NIR photoluminescence, unique Raman signature, photothermal response, and large surface area for the covalent and non-covalent conjugation of contrast agents and drugs, DNA/RNA. However, pristine CNT are highly hydrophobic and not biocompatible, requiring functionalization with hydrophilic molecules in order to form stable aqueous suspensions. Here, simple functionalization methods of perylene bisimides and pyrene, to render these polyaromatic molecules amphiphilic, will be presented. Bolaamphiphilic perylene bisimides (PBI) were prepared by the reaction of perylenetetracarboxylic dianhydride with -amino acids in good yield, using a simple protocol and avoiding complex purification methods. [1] Pyrene was modified by nitration followed by amination, and further reacted with maleic anhydride yielding carboxylic acid-functionalized pyrene. The CNT aqueous suspensions were studied by absorption and emission spectroscopy. Theoretical calculations were used to support the experimental observations. The possibility of CNT double functionalization (covalent and non-covalent) will be discussed based on CNT solubility studies in surfactant aqueous solutions. Pristine and covalently functionalized CNT, at different functionalization yields, were compared. The CNT were functionalized by the 1,3-dipolar cycloaddition of azomethine ylides. [2] The ability of CNT to adsorb surfactant molecules was reduced by the covalent functionalization. Nevertheless, depending on the extent of covalent functionalization, a high concentration of CNT in water could be attained, in comparison to that of pristine CNT.Fundação para a Ciência e a Tecnologia (FCT

Application of Light Scattering Techniques to Nanoparticle Characterization and Development

Over the years, the scientific importance of nanoparticles for biomedical applications has increased. The high stability and biocompatibility, together with the low toxicity of the nanoparticles developed lead to their use as targeted drug delivery systems, bioimaging systems, and biosensors. The wide range of nanoparticles size, from 10 nm to 1 μm, as well as their optical properties, allow them to be studied using microscopy and spectroscopy techniques. In order to be effectively used, the physicochemical properties of nanoparticle formulations need to be taken into account, namely, particle size, surface charge distribution, surface derivatization and/or loading capacity, and related interactions. These properties need to be optimized considering the final nanoparticle intended biodistribution and target. In this review, we cover light scattering based techniques, namely dynamic light scattering and zeta-potential, used for the physicochemical characterization of nanoparticles. Dynamic light scattering is used to measure nanoparticles size, but also to evaluate their stability over time in suspension, at different pH and temperature conditions. Zeta-potential is used to characterize nanoparticles surface charge, obtaining information about their stability and surface interaction with other molecules. In this review, we focus on nanoparticle characterization and application in infection, cancer and cardiovascular diseases

XRD and FTIR analysis of Ti–Si–C–ON coatings for biomedical applications

Ti–Si–C–ON films were deposited by DC reactive magnetron sputtering using different partial pressure ratio of oxygen (pO2) and nitrogen (pN2). Compositional analysis revealed the existence of three different growth zones for the films; (I) N/Ti = 2.1 (high atomic ratio) and low oxygen content; (II) 0.76 < N/Ti < 2.1 (intermediate atomic ratio) and (III) N/Ti ≤ 0.12 (low ratio) and high oxygen content. For high N/Ti atomic ratio (N/Ti = 2.1) the XRD pattern exhibits reflections that correspond to a mixture of two different phases: a metallic-like Ti and a fcc NaCl type structure. Its electrical resistivity presents a metallic character and, consequently, has high infrared reflectivity. For the intermediate N/Ti ratio (0.76 < N/Ti < 2.1), the films crystallize in a B1-NaCl crystal structure typical for TiC0.2N0.8. Their FTIR spectra present C–N modes, besides the TiN ones, that indicate a progressive substitution of nitrogen by carbon atoms with increasing oxygen content (and lowering N/Ti ratio). For the highest oxygen content (and lower N/Ti ratio) the presence of the Ti–O–Ti stretching mode shows the formation of highly resistive Ti–O compounds consistent with the semiconductor character of this film. Biofilm formation as well as material cytotoxicity seemed to be related with the presence of the Ti