Application of molecular topology to the prediction of the repellent activity of a group of carboxyamides against Aedes aegypti

El mosquito Aedes aegypti presenta características biológicas que lo convierten en un vector importante en el ciclo de transmisión de diferentes patógenos, en especial arbovirus. Durante la última década, la carga de dengue y otras enfermedades tales como la fiebre del zika o fiebre chikungunya se han incrementado. La expansión de dengue ocasionada por este vector, principalmente en América, representa actualmente uno de los problemas más grandes de salud pública, siendo endémico en más de 30 países. Frente a la falta de tratamientos específicos para tratar las infecciones transmitidas por este mosquito, los esfuerzos por hacerle frente se han focalizado en el control vectorial, aplicando diversas estrategias de combate, entre las que se incluye la aplicación de insecticidas y larvicidas para conseguir su eliminación, así como el uso de repelentes como estrategia de protección individual. La búsqueda de nuevos repelentes puede realizarse mediante diferentes herramientas, donde se incluye la topología molecular. En este contexto, computacionalmente a través de un modelo topológico-matemático, evaluamos la potencial actividad repelente de una serie de carboxiamidas preseleccionadas mediante el uso de análisis discriminante lineal y de regresión multilineal. Tras este cribado virtual basado en el modelo seleccionado, proponemos nuevas estructuras químicas con una actividad potencialmente activa como repelentes contra Aedes aegypti.Due to its biological characteristics, the mosquito Aedes aegypti is an important vector in the transmission cycle of various pathogens, especially of arboviruses. The burden of dengue and other diseases such as the Zika virus infection or the chikungunya fever has increased over the last decade. The spread of dengue caused by this vector, mainly in America, represents one of the greatest public health problems, being endemic in more than 30 countries. Faced with the lack of specific treatments to treat the infections caused by this mosquito, efforts have focused on controlling the vector, applying various combat strategies, including the application of Due to its biological characteristics, the mosquito Aedes aegypti is an important vector in the transmission cycle of various pathogens, especially of arboviruses. The burden of dengue and other diseases such as the Zika virus infection or the chikungunya fever has increased over the last decade. The spread of dengue caused by this vector, mainly in America, represents one of the greatest public health problems, being endemic in more than 30 countries. Faced with the lack of specific treatments to treat the infections caused by this mosquito, efforts have focused on controlling the vector, applying various combat strategies, including the application of insecticides and larvicides to directly eliminate the mosquito population, as well as the use of repellants, as an individual protection strategy. The search for new repellants can be done using different tools, including molecular topology. In this context, using a topological-mathematical model, we evaluated the potential repellent activity of a series of preselected carboxyamides by using linear discriminant and multilinear regression analysis. After carrying out a virtual screening based on the selected model, new chemical structures with potential activity as repellants against Aedes aegypti are proposed.Ciencias Experimentale

An accurate test for homogeneity of odds ratios based on Cochran's Q-statistic

Background: A frequently used statistic for testing homogeneity in a meta-analysis of K independent studies is Cochran's Q. For a standard test of homogeneity the Q statistic is referred to a chi-square distribution with K - 1 degrees of freedom. For the situation in which the effects of the studies are logarithms of odds ratios, the chi-square distribution is much too conservative for moderate size studies, although it may be asymptotically correct as the individual studies become large. Methods: Using a mixture of theoretical results and simulations, we provide formulas to estimate the shape and scale parameters of a gamma distribution to t the distribution of Q. Results: Simulation studies show that the gamma distribution is a good approximation to the distribution for Q. Conclusions: : Use of the gamma distribution instead of the chi-square distribution for Q should eliminate inaccurate inferences in assessing homogeneity in a meta-analysis. (A computer program for implementing this test is provided.) This hypothesis test is competitive with the Breslow-Day test both in accuracy of level and in power

Space time transformation acoustics

A recently proposed analogue transformation method has allowed the extension of transformation acoustics to general space-time transformations. We analyze here in detail the differences between this new analogue transformation acoustics (ATA) method and the standard one (STA). We show explicitly that STA is not suitable for transformations that mix space and time. ATA takes as starting point the acoustic equation for the velocity potential, instead of that for the pressure as in STA. This velocity-potential equation by itself already allows for some transformations mixing space and time, but not all of them. We explicitly obtain the entire set of transformations that leave its form invariant. It is for the rest of transformations that ATA shows its true potential, allowing for building a transformation acoustics method that enables the full range of space-time transformations. We provide an example of an important transformation which cannot be achieved with STA. Using this transformation, we design and simulate an acoustic frequency converter via the ATA approach. Furthermore, in those cases in which one can apply both the STA and ATA approaches, we study the different transformational properties of the corresponding physical quantities.This work was developed under the framework of the ARIADNA contracts 4000104572/11/NL/KML and 4000104572/12/NL/KML of the European Space Agency. C.G.-M., J.S.-D., and A.M. also acknowledge support from Consolider EMET project (CSD2008-00066), A.M. from project TEC2011-28664-C02-02, C.B. and GJ. from the project FIS2008-06078-C03-01, and J.S.-D. from the Office of Naval Research (Grant No. N00014-12-1-0216).García Meca, C.; Carloni, S.; Barceló, C.; Jannes, G.; Sánchez-Dehesa Moreno-Cid, J.; Martínez Abietar, AJ. (2014). Space time transformation acoustics. Wave Motion. 51(5):785-797. https://doi.org/10.1016/j.wavemoti.2014.01.008S78579751

Rabdomiosarcoma paratesticular: reporte de caso y revisión de la literatura

Objetivo: Ofrecer un alcance de la relevancia del diagnóstico oportuno del cáncer testicular, a partir de un caso infrecuente de rabdomiosarcoma paratesticular en un adulto. Reporte de Caso: Se trata de un paciente varón de 39 años, que ingresa al servicio de cirugía - urología por un aumento de volumen de contenido escrotal, de forma progresiva desde hace 2 años, con crecimiento paulatino de la masa. En la ecografía testicular se evidencia un notorio aumento de volumen de bolsas escrotales por aparente tumoración o masa de consistencia dura, de estructura heterogénea y aspecto sólido de bordes mal definidos. Considerando los hallazgos clínicos, marcadores testiculares e imagenológicos se diagnosticó un tumor paratesticular derecho. Se realizó una orquiectomía derecha más exéresis de tumor paratesticular derecho. Patología concluyó en rabdomiosarcoma embrionario paratesticular con cápsula rota. Paciente fue dado de alta con seguimiento por consulta externa y referido a hospital oncológico de cuarto nivel

Transformational acoustic metamaterials based on pressure gradients

We apply a homogenization process to the acoustic velocity potential wave equation. The study of various examples shows that the resulting effective properties are different from those of the homogenized pressure wave equation for the same underlying acoustic parameters. A careful analysis reveals that a given set of inhomogeneous parameters represents an entirely different physical system depending on the considered equation. Our findings unveil a different way of tailoring acoustic properties through gradients of the static pressure. In contrast to standard metafluids based on isobaric composites, this alternative kind of metafluid is suitable for the implementation of transformational devices designed via the velocity potential equation. This includes acoustic systems in a moving background or arising from general space-time transformations. As an example, we design a device able to cloak the acoustic velocity potential.This work was developed under the framework of the ARIADNA Contract No. 4000104572/12/NL/KML of the European Space Agency. C.G.-M., J.S.-D., and A.M. also acknowledge support from Consolider project CSD2008-00066, A.M. from project TEC2011-28664-C02-02, and C.B. and G.J. from the project FIS2011-30145-C03-01. J.S.-D. acknowledges support from the USA Office of Naval Research. All authors contributed equally to this work.García Meca, C.; Carloni, S.; Barceló, C.; Jannes, GGP.; Sánchez-Dehesa Moreno-Cid, J.; Martínez Abietar, AJ. (2014). Transformational acoustic metamaterials based on pressure gradients. Physical Review B. 90(2):24310-1-24310-9. https://doi.org/10.1103/PhysRevB.90.024310S24310-124310-990

Cross validation of bi-modal health-related stress assessment

This study explores the feasibility of objective and ubiquitous stress assessment. 25 post-traumatic stress disorder patients participated in a controlled storytelling (ST) study and an ecologically valid reliving (RL) study. The two studies were meant to represent an early and a late therapy session, and each consisted of a "happy" and a "stress triggering" part. Two instruments were chosen to assess the stress level of the patients at various point in time during therapy: (i) speech, used as an objective and ubiquitous stress indicator and (ii) the subjective unit of distress (SUD), a clinically validated Likert scale. In total, 13 statistical parameters were derived from each of five speech features: amplitude, zero-crossings, power, high-frequency power, and pitch. To model the emotional state of the patients, 28 parameters were selected from this set by means of a linear regression model and, subsequently, compressed into 11 principal components. The SUD and speech model were cross-validated, using 3 machine learning algorithms. Between 90% (2 SUD levels) and 39% (10 SUD levels) correct classification was achieved. The two sessions could be discriminated in 89% (for ST) and 77% (for RL) of the cases. This report fills a gap between laboratory and clinical studies, and its results emphasize the usefulness of Computer Aided Diagnostics (CAD) for mental health care

Order-of-magnitude speedup for steady states and traveling waves via Stokes preconditioning in Channelflow and Openpipeflow

Steady states and traveling waves play a fundamental role in understanding hydrodynamic problems. Even when unstable, these states provide the bifurcation-theoretic explanation for the origin of the observed states. In turbulent wall-bounded shear flows, these states have been hypothesized to be saddle points organizing the trajectories within a chaotic attractor. These states must be computed with Newton's method or one of its generalizations, since time-integration cannot converge to unstable equilibria. The bottleneck is the solution of linear systems involving the Jacobian of the Navier-Stokes or Boussinesq equations. Originally such computations were carried out by constructing and directly inverting the Jacobian, but this is unfeasible for the matrices arising from three-dimensional hydrodynamic configurations in large domains. A popular method is to seek states that are invariant under numerical time integration. Surprisingly, equilibria may also be found by seeking flows that are invariant under a single very large Backwards-Euler Forwards-Euler timestep. We show that this method, called Stokes preconditioning, is 10 to 50 times faster at computing steady states in plane Couette flow and traveling waves in pipe flow. Moreover, it can be carried out using Channelflow (by Gibson) and Openpipeflow (by Willis) without any changes to these popular spectral codes. We explain the convergence rate as a function of the integration period and Reynolds number by computing the full spectra of the operators corresponding to the Jacobians of both methods.Comment: in Computational Modelling of Bifurcations and Instabilities in Fluid Dynamics, ed. Alexander Gelfgat (Springer, 2018

A systematic review and meta-analysis of the effects of flavanol-containing tea, cocoa and apple products on body composition and blood lipids: exploring the factors responsible for variability in their efficacy

Several randomized controlled trials (RCTs) and meta-analyses support the benefits of flavanols on cardiometabolic health, but the factors affecting variability in the responses to these compounds have not been properly assessed. The objectives of this meta-analysis were to systematically collect the RCTs-based-evidence of the effects of flavanol-containing tea, cocoa and apple products on selected biomarkers of cardiometabolic risk and to explore the influence of various factors on the variability in the responses to the consumption of these products. A total of 120 RCTs were selected. Despite a high heterogeneity, the intake of the flavanol-containing products was associated using a random model with changes (reported as standardized difference in means (SDM)) in body mass index (−0.15, p < 0.001), waist circumference (−0.29, p < 0.001), total-cholesterol (−0.21, p < 0.001), LDL-cholesterol (−0.23, p < 0.001), and triacylglycerides (−0.11, p = 0.027), and with an increase of HDL-cholesterol (0.15, p = 0.005). Through subgroup analyses, we showed the influence of baseline-BMI, sex, source/form of administration, medication and country of investigation on some of the outcome measures and suggest that flavanols may be more effective in specific subgroups such as those with a BMI ≥ 25.0 kg/m2, non-medicated individuals or by specifically using tea products. This meta-analysis provides the first robust evidence of the effects induced by the consumption of flavanol-containing tea, cocoa and apple products on weight and lipid biomarkers and shows the influence of various factors that can affect their bioefficacy in humans. Of note, some of these effects are quantitatively comparable to those produced by drugs, life-style changes or other natural products. Further, RCTs in well-characterized populations are required to fully comprehend the factors affecting inter-individual responses to flavanol and thereby improve flavanols efficacy in the prevention of cardiometabolic disordersinfo:eu-repo/semantics/publishedVersio