ANÁLISE Numérica de Cisalhamento em Lajes Alveolares Protendidas

Este trabalho analisa numericamente o comportamento de lajes alveolares protendidas de uso corrente no Brasil quanto ao cisalhamento, para diferentes situações: sem capa estrutural, com variações na protensão e no posicionamento dos apoios. Buscando estudar, compreender e aperfeiçoar o uso destas peças, são realizadas modelagens por meio de uma análise numérica via elementos finitos utilizando o programa computacional ANSYS V.15 para reproduzir ensaios físicos já realizados e assim comparar os resultados numéricos aos experimentais a fim de calibrar o uso do programa para o estudo destas lajes. Os resultados obtidos são comparados com resultados teóricos obtidos por meio da utilização das formulações disponíveis nas normas ABNT NBR 14861:2011 e ABNT NBR 6118:2014. Logo, com esta pesquisa, foi possível mensurar o conservadorismo na norma brasileira vigente para o cálculo da resistência ao cisalhamento de lajes alveolares protendidas sem capa estrutural, ampliando o embasamento teórico e vislumbrando novos trabalhos acerca do assunto

DOPAL derived alpha-synuclein oligomers impair synaptic vesicles physiological function

Parkinson's disease is a neurodegenerative disorder characterized by the death of dopaminergic neurons and by accumulation of alpha-synuclein (aS) aggregates in the surviving neurons. The dopamine catabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL) is a highly reactive and toxic molecule that leads to aS oligomerization by covalent modifications to lysine residues. Here we show that DOPAL-induced aS oligomer formation in neurons is associated with damage of synaptic vesicles, and with alterations in the synaptic vesicles pools. To investigate the molecular mechanism that leads to synaptic impairment, we first aimed to characterize the biochemical and biophysical properties of the aS-DOPAL oligomers; heterogeneous ensembles of macromolecules able to permeabilise cholesterol-containing lipid membranes. aS-DOPAL oligomers can induce dopamine leak in an in vitro model of synaptic vesicles and in cellular models. The dopamine released, after conversion to DOPAL in the cytoplasm, could trigger a noxious cycle that further fuels the formation of aS-DOPAL oligomers, inducing neurodegeneration

Metodologias de análise da atividade de duas enzimas com potencial uso em biossensores

As enzimas superóxido dismutase (SOD) e catalase (CAT) fazem parte dos sistemas antioxidantes nos seres vivos. A alteração da atividade da CAT e SOD extraídas de organismos expostos a poluentes químicos tem sido estudada na avaliação ecotoxicológica. São apresentados os resultados preliminares referentes à implementação de metodologias para avaliar as atividades de SOD e CAT frente à possível ação de diversos poluentes de origem agrícola. As metodologias empregadas demonstraram ser satisfatórias para estudos do potencial das enzimas no desenvolvimento de biossensores. Entretanto, alguns ajustes metodológicos poderão ser realizados com relação a uma melhor adaptação às condições laboratoriais

A kinematic examination of dual-route processing for action imitation

The dual-route model of imitation suggests that meaningful and meaningless actions are processed through either an indirect or direct route, respectively. Evidence indicates that the direct route is more cognitively demanding, since it relies on mapping visuospatial properties of the observed action on to a performed one. These cognitive demands might negatively influence reaction time and accuracy for actions performed following a meaningless action under time constraints. However, how meaningful and meaningless action imitation processing is reflected in movement kinematics is not yet clear. We wanted to confirm whether meaningless action performance incurs a reaction time cost, whether the cost is reflected in kinematics, and, more generally, to examine kinematic markers of emblematic meaningful and meaningless action imitation. We examined participants’ reaction time and wrist movements when they imitated emblematic meaningful or matched meaningless gestures in either blocks of the same action type, or mixed blocks. Meaningless actions were associated with a greater correction period at the end of the movement, possibly reflecting a strategy designed to ensure accurate completion for less familiar actions under time constraints. Furthermore, in mixed blocks, trials following meaningless actions had a significantly increased reaction time, supporting previous claims that route selection for action imitation may be stimulus-driven. However, there was only convincing evidence for this effect with an interval of ~2948ms, but not ~3573ms or ~2553ms, between movements. Future work motion-tracking the entire hand to assess imitation accuracy, and more closely examining the influence of duration between movements, may help to explain these effects

Efficacy of pulsatile flow perfusion in adult cardiac surgery: Hemodynamic energy and vascular reactivity

Background: The role of pulsatile (PP) versus non-pulsatile (NP) flow during a cardiopulmonary bypass (CPB) is still debated. This study’s aim was to analyze hemodynamic effects, endothelial reactivity and erythrocytes response during a CPB with PP or NP. Methods: Fifty-two patients undergoing an aortic valve replacement were prospectively randomized for surgery with either PP or NP flow. Pulsatility was evaluated in terms of energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE). Systemic (SVRi) and pulmonary (PVRi) vascular resistances, endothelial markers levels and erythrocyte nitric-oxide synthase (eNOS) activity were collected at different perioperative time-points. Results: In the PP group, the resultant EEP was 7.3% higher than the mean arterial pressure (MAP), which corresponded to 5150 ± 2291 ergs/cm3 of SHE. In the NP group, the EEP and MAP were equal; no SHE was produced. The PP group showed lower SVRi during clamp-time (p = 0.06) and lower PVRi after protamine administration and during first postoperative hours (p = 0.02). Lower SVRi required a higher dosage of norepinephrine in the PP group (p = 0.02). Erythrocyte eNOS activity results were higher in the PP patients (p = 0.04). Renal function was better preserved in the PP group (p = 0.001), whereas other perioperative variables were comparable between the groups. Conclusions: A PP flow during a CPB results in significantly lower SVRi, PVRi and increased eNOS production. The clinical impact of increased perioperative vasopressor requirements in the PP group deserves further evaluation

A phase I study of PankoMab-GEX, a humanised glyco-optimised monoclonal antibody to a novel tumour-specific MUC1 glycopeptide epitope in patients with advanced carcinomas

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Biomonitoramento de fungicida na urina de ratas prenhas: estudo do metalaxil.

Sabe-se que alterações no sistema reprodutivo e na fase de desenvolvimento animal podem ter impactos na sobrevivência da prole. Uma vez que os agrotóxicos são geralmente mais tóxicos em animais imaturos do que em adultos, o presente trabalho visou estudar alguns parâmetros a serem utilizados na medida de bioindicadores de exposição (dose interna) e que possam ser utilizados como mecanismo de previsão dos efeitos destes produtos em doses que aparentemente não causam danos. Para tanto foram avaliadas fêmeas expostas a 10 e 20 mg Kg ?1 de metalaxil v.o. durante os dias 7, 11 e 15 da prenhez. As ratas tiveram coletadas amostras de urina diariamente após o primeiro dia da exposição até o dia 19 do período gestacional. Elas também tiveram seu ganho de peso medido até o dia 20 da prenhez. Não foram encontradas alterações quanto ao ganho de peso. Os aumentos da quantidade excretada de metalaxil da maior dose, no dia seguinte a cada administração, foram respectivamente de 2,96; 5,22 e 19,84 vezes maior que na menor dose. O estabelecimento de indicadores de dose interna que quantifique o metalaxil e/ ou seus metabólitos no organismo podem auxiliar na avaliação dos efeitos decorrentes da exposição perinatal a agrotóxicos.bitstream/CNPMA/5375/1/boletim_27.pd

Randomized controlled trial comparing the effectiveness of 308-nm excimer laser alone or in combination with topical hydrocortisone 17-butyrate cream in the treatment of vitiligo of the face and neck.

Background Vitiligo is a pigmentary disorder which may have disfiguring consequences. Its treatment remains a challenge. Objectives We designed a parallel-group randomized controlled trial to compare the effectiveness of 308-nm excimer laser alone or in combination with topical hydrocortisone 17-butyrate cream in patients with vitiligo unresponsive to previous treatment with topical steroids or narrow-band ultraviolet (UV) B phototherapy. Methods Consecutive patients aged 18\u201375 years with nonsegmental vitiligo localized on the face and \u2044or neck lacking response to previous conventional treatment were eligible. In total, 84 patients (44 women and 40 men, mean age 44 years) were randomized to 308-nm excimer laser phototherapy twice weekly alone or in combination with topical hydrocortisone 17-butyrate cream twice daily for three periods of 3 weeks followed by a 1-week steroid-free interval. The primary outcome was a reduction of at least 75% of the overall lesional areas as judged by automatic image analysis on reflected UV photographs, conducted blind to treatment assignment, at 12 weeks compared with baseline. Secondary outcomes were clearance, and improvements on Physician\u2019s Global Assessment (PGA) and Skindex-29 scores. Results A total of 76 (90%) patients completed the study. In an intention-to-treat analysis, seven [16\uc66%; 95% confidence interval (CI) 5\uc63\u201327\uc68%] patients in the excimer monotherapy arm and 18 (42\uc68%; 95% CI 27\uc68\u201357\uc68%) in the combination arm showed \u2021 75% reduction of vitiligo lesions at 12 weeks (v2 test 6\uc689, P = 0\uc60087). Clearance was observed in two (4\uc67%; 95% CI 1\uc66\u201311\uc62%) and nine (21\uc64%; 95% CI 9\uc60\u201333\uc68%) patients, respectively (Fisher\u2019s exact test P = 0\uc604). A significant difference also emerged for PGA scores, while no difference was documented for Skindex-29. Conclusions Recalcitrant vitiligo of the face and neck may benefit from the combination of excimer laser phototherapy with topical hydrocortisone 17-butyrate cream

Spectral characteristics of the internal jugular vein and central venous pressure pulses: a proof of concept study

In this proof-of-concept study the impact of central venous pressure (CVP) on internal jugular veins cross-sectional area (CSA) and blood flow time-average velocity (TAV) was evaluated in eight subjects, with the aim of understanding the drivers of the jugular venous pulse. CVP was measured using a central venous catheter while CSA variation and TAV along a cardiac cycle were acquired using ultrasound. Analysis of CVP, CSA and TAV time-series signals revealed TAV and CSA to lag behind CVP by on average 0.129 s and 0.138 s, with an inverse correlation between CSA and TAV (r= –0.316). The respective autocorrelation signals were strongly correlated (mean r=0.729-0.764), with mean CSA periodicity being 1.062 Hz. Fourier analysis revealed the frequency spectrums of CVP, TAV and CSA signals to be dominated by frequencies at approximately 1 and 2 Hz, with those >1 Hz greatly attenuated in the CSA signal. Because the autocorrelograms and periodograms of the respective signals were aligned and dominated by the same underlying frequencies, this suggested that they are more easily interpreted in the frequency domain rather than the time domain