253 research outputs found
A simple point of care test can indicate the need for periodontal therapy to reduce the risk for adverse pregnancy outcomes in mothers attending antenatal clinics
INTRODUCTION: Although the association between periodontal disease (PD) and adverse pregnancy
outcomes has gained recognition amongst antenatal healthcare workers, not much has changed in
practice to address it. This prospective study tested the hypothesis that BANA (N-benzoyl-DL-arginine-
2-naphthylamide), a diagnostic test for PD, may inform obstetricians and other antenatal healthcare
practitioners, of the risk of adverse pregnancy outcomes in mothers attending antenatal clinics.
METHODS: At first visit, the presence of suspected periodontopathogens was assessed by BANA testing
of dental plaque from 443 mothers attending antenatal clinics in KwaZulu-Natal, South Africa and an
association later sought with pregnancy outcomes. The accuracy of BANA to predict adverse pregnancy
outcomes was evaluated by the calculation of likelihood ratios. The study complied with the
Declaration of Helsinki.
RESULTS: Significant differences were found between pregnancy outcomes of BANA-negative and
BANA-positive mothers (p<0.0001). BANA showed sensitivity and negative predictive values of 87%
and 91%; 75% and 78%; 87% and 94% in detecting low birth weight, preterm delivery, and preterm
low birth weight delivery respectively.
CONCLUSION: This study confirms that BANA may indicate the need for periodontal therapy to reduce
the risk of adverse pregnancy outcomes and could form part of the routine antenatal examination.National Research Foundation (NRF
Morfoanatomia foliar em mudas de Schinus terebinthifolius sob diferentes nÃveis de saturação hÃdrica.
As caracterÃsticas morfológicas e anatômicas foliares de espécies vegetais são importantes indicadores de sua ecologia e de seus hábitats. Objetivou-se caracterizar a plasticidade fenotÃpica de Schinus terebinthifolius Raddi em diferentes condições de saturação hÃdrica. As mudas foram produzidas em tubetes plásticos, permanecendo em estufa por quatro meses, sendo irrigadas normalmente. Em seguida foram submetidas aos tratamentos: T1- testemunha, T2- alagamento parcial e T3- alagamento total. Após três semanas sob alagamento, foram realizadas descrições anatômicas foliares comparativas e avaliadas as caracterÃsticas morfológicas área foliar, área especÃfica foliar, espessura foliar, teor de água e densidade estomática. Durante 10 semanas foram observadas as modificações fenotÃpicas adaptativas. Foi observado aumento da espessura da base do caule, clorose e abscisão foliar, surgimento de lenticelas e raÃzes adventÃcias. Após três semanas de alagamento, não foram verificadas grandes modificações na morfologia das folhas, principalmente para a AF e AEF. Em T3, o teor de água foi maior e a espessura foliar menor. Não houve diferença entre os tratamentos para DE. Quanto aos aspectos anatômicos, observou-se uma redução na espessura do mesofilo e das nervuras, assim como a produção de compostos fenólicos por alguns tipos celulares. Os espaços intercelulares são progressivamente mais amplos nas plantas submetidas ao alagament
3D printed microchannels for sub-nL NMR spectroscopy
Nuclear magnetic resonance (NMR) experiments on subnanoliter (sub-nL) volumes are hindered by the limited sensitivity of the detector and the difficulties in positioning and holding such small samples in proximity of the detector. In this work, we report on NMR experiments on liquid and biological entities immersed in liquids having volumes down to 100 pL. These measurements are enabled by the fabrication of high spatial resolution 3D printed microfluidic structures, specifically conceived to guide and confine sub-nL samples in the sub-nL most sensitive volume of a single-chip integrated NMR probe. The microfluidic structures are fabricated using a two-photon polymerization 3D printing technique having a resolution better than 1 \u3bcm3. The high spatial resolution 3D printing approach adopted here allows to rapidly fabricate complex microfluidic structures tailored to position, hold, and feed biological samples, with a design that maximizes the NMR signals amplitude and minimizes the static magnetic field inhomogeneities. The layer separating the sample from the microcoil, crucial to exploit the volume of maximum sensitivity of the detector, has a thickness of 10 \u3bcm. To demonstrate the potential of this approach, we report NMR experiments on sub-nL intact biological entities in liquid media, specifically ova of the tardigrade Richtersius coronifer and sections of Caenorhabditis elegans nematodes. We show a sensitivity of 2.5x1013spins/ Hz1/2on1H nuclei at 7 T, sufficient to detect 6 pmol of1H nuclei of endogenous compounds in active volumes down to 100 pL and in a measurement time of 3 hours. Spectral resolutions of 0.01 ppm in liquid samples and of 0.1 ppm in the investigated biological entities are also demonstrated. The obtained results may indicate a route for NMR studies at the single unit level of important biological entities having sub-nL volumes, such as living microscopic organisms and eggs of several mammalians, humans included
hybridModels: An R Package for the Stochastic Simulation of Disease Spreading in Dynamic Networks
Disease spreading simulations are traditionally performed using coupled differential equations. However, in the setting of metapopulations, most of the solutions provided by this method do not account for the dynamic topography of subpopulations. Conversely, the alternative approach of individual-based modeling (IBM) may add computational cost and complexity. Hybrid models allow for the study of disease spreading because they combine both aforementioned approaches by separating them across different scales: a local scale that addresses subpopulation dynamics using coupled differential equations and a global scale that addresses the contact between these subpopulations using IBM. We present a simple way of simulating the spread of disease in dynamic networks using the high-level statistical computational language R and the hybridModels package. We built four examples using disease spread models at the local scale in several different networks: an animal movement network; a three-node network, whose model solution using a stochastic simulation algorithm is compared with the ordinary differential equations approach; the commuting of individuals between patches, which we compare with the permanent migration of individuals; and the commuting of individuals within the metropolitan area of São Paulo
Evidence of field-evolved resistance of Spodoptera frugiperda to Bt corn expressing Cry1F in Brazil that is still sensitive to modified bt toxins.
Effect of biofunctionalized implant surface on osseointegration: a histomorphometric study in dogs
Among the different properties that influence bone apposition around implants, the chemical or biochemical composition of implant surface may interfere on its acceptance by the surrounding bone. The aim of this study was to investigate if a biofunctionalization of implant surface influences the bone apposition in a dog model and to compare it with other surfaces, such as a microstructured created by the grit-blasting/acid-etching process. Eight young adult male mongrel dogs had the bilateral mandibular premolars extracted and each one received 6 implants after 12 weeks, totaling 48 implants in the experiment. Four groups of implants were formed with the same microrough topography with or without some kind of biofunctionalization treatment. After histomorphometric analysis, it was observed that the modified microstructured surface with a "low concentration of the bioactive peptide" provided a higher adjacent bone density (54.6%) when compared to the other groups (microstructured + HA coating = 46.0%, microstructured only = 45.3% and microstructured + "high concentration of the bioactive peptide" = 40.7%), but this difference was not statistically significant. In conclusion, biofunctionalization of the implant surface might interfere in the bone apposition around implants, especially in terms of bone density. Different concentrations of bioactive peptide lead to different results.Entre as diferentes propriedades de uma superfÃcie capazes de influenciar a deposição óssea ao redor de implantes, a composição quÃmica e bioquÃmica pode atuar no reconhecimento do tecido ósseo circundante. O presente trabalho investigou a influência da biofuncionalização de superfÃcies de implante na deposição óssea ao redor dos mesmos em um modelo animal, comparando-as com outras superfÃcies, como a microtexturizada obtida pelo processo de jateamento e ataque ácido. Metodologicamente, os pré-molares mandibulares bilaterais de 8 cães foram extraÃdos e após 12 semanas foram instalados 6 implantes em cada cão, constituindo uma amostra de 48 implantes. Dos 4 grupos experimentais de diferentes superfÃcies, todos continham a mesma microtopografia rugosa, porém possuindo ou não alguma biofuncionalização. A análise histomorfométrica revelou que a superfÃcie microtexturizada modificada pela adição de baixa concentração peptÃdica obteve uma maior densidade óssea adjacente (54,6%) quando comparada aos outros grupos (microtexturizada + HA = 46%, somente microtexturizada = 45,3% e microtexturizada com adição de alta concentração peptÃdica = 40,7%), no entanto estas diferenças numéricas não foram estatisticamente significantes. Dentro deste contexto, conclui-se que a biofuncionalização da superfÃcie de implantes pode interferir na aposição óssea, em particular na densidade óssea, e que diferentes concentrações peptÃdicas podem conduzir a diferentes resultados.FAPES
On the Fibonacci universality classes in nonlinear fluctuating hydrodynamics
We present a lattice gas model that without fine tuning of parameters is
expected to exhibit the so far elusive modified Kardar-Parisi-Zhang (KPZ)
universality class. To this end, we review briefly how non-linear fluctuating
hydrodynamics in one dimension predicts that all dynamical universality classes
in its range of applicability belong to an infinite discrete family which we
call Fibonacci family since their dynamical exponents are the Kepler ratios
of neighbouring Fibonacci numbers , including
diffusion (), KPZ (), and the limiting ratio which is the
golden mean . Then we revisit the case of two
conservation laws to which the modified KPZ model belongs. We also derive
criteria on the macroscopic currents to lead to other non-KPZ universality
classes.Comment: 17 page
Gestational age acceleration is associated with epigenetic biomarkers of prenatal physiologic stress exposure
BACKGROUND: Physiological maternal stress response, such as imbalance in the glucocorticoid pathway and immune system seems to be mediated by DNA methylation (DNAm) and might translate intrauterine stress exposures into phenotypic changes in a sex-specific manner. DNAm in specific sites can also predict newborn gestational age and gestational age acceleration (GAA). GAA occurs when the predicted biological age is higher than the chronological age. In adults, poor health outcomes related to this deviance are well documented and raise questions for the interpretation and prediction in early stages of life. Boys seem to be more vulnerable to intrauterine stress exposure than girls; however, the mechanisms of adaptive sex-specific responses are still unclear. We hypothesize that intrauterine stress exposure is associated with GAA and could be different in boys and girls if inflammatory or glucocorticoid pathways exposure is considered. RESULTS: Using the Western Region Birth Cohort (ROC-Sao Paulo, Brazil) (n = 83), we calculated DNAm age and GAA from cord blood samples. Two epigenetic risk scores were calculated as an indirect proxy for low-grade inflammation (i-ePGS) and for glucocorticoid exposure (GES). Multivariate linear regression models were applied to investigate associations of GAA with prenatal exposures. The i-ePGS and GES were included in different models with the same co-variates considering sex interactions. The first multivariate model investigating inflammatory exposure (adj. R(2) = 0.31, p = < 0.001) showed that GAA was positively associated with i-ePGS (CI, 0.26-113.87, p = 0.049) and negative pregnancy-related feelings (CI, 0.04-0.48 p = 0.019). No sex interaction was observed. The second model investigating glucocorticoid exposure (adj. R(2) = 0.32, p = < 0.001) showed that the higher was the GAA was associated with a lower the lower was the GES in girls (CI, 0.04-2.55, p = 0.044). In both models, maternal self-reported mental disorder was negatively associated with GAA. CONCLUSION: Prenatal epigenetic score of exposure to low-grade inflammatory was a predictor of GAA for both sexes. Glucocorticoid epigenetic score seems to be more important to GAA in girls. This study supports the evidence of sex-specificity in stress response, suggesting the glucocorticoid as a possible pathway adopted by girls to accelerate the maturation in an adverse condition
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