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(Ril editores, 2016) Del Barrio Vásquez, Diego
Taxanes for advanced non-small cell lung cancer (Protocol)
(Cochrane, 2018) Madrid, Eva; Barros Monge, Manuel J; Urrútia, Gerard; Roqué I Figuls, Marta; Pérez Bracchiglione, Javier; Vargas Peirano, Manuel; Loézar Hernández, Cristóbal Nicolás; Bonfill Cosp, Xavier
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the effects of taxanes as part of a combined or single‐agent therapy versus other agents or best supportive care as first‐ or second‐line treatment for advanced non‐small cell lung cancer (NSCLC). A secondary objective is to assess different modes or schemes of administration of taxanes in patients with this disease.
Chaos versus noise as drivers of multistability in neural networks
(Chaos, 2018-10-18) Orio, Patricio; Gatica, Marilyn; Herzog, Rubén; Maidana, Jean Paul; Castro, Samy; Xu, Kesheng
The multistable behavior of neural networks is actively being studied as a landmark of ongoing cerebral activity, reported in both functional Magnetic Resonance Imaging (fMRI) and electro- or magnetoencephalography recordings. This consists of a continuous jumping between different partially synchronized states in the absence of external stimuli. It is thought to be an important mechanism for dealing with sensory novelty and to allow for efficient coding of information in an ever-changing surrounding environment. Many advances have been made to understand how network topology, connection delays, and noise can contribute to building this dynamic. Little or no attention, however, has been paid to the difference between local chaotic and stochastic influences on the switching between different network states. Using a conductance-based neural model that can have chaotic dynamics, we showed that a network can show multistable dynamics in a certain range of global connectivity strength and under deterministic conditions. In the present work, we characterize the multistable dynamics when the networks are, in addition to chaotic, subject to ion channel stochasticity in the form of multiplicative (channel) or additive (current) noise. We calculate the Functional Connectivity Dynamics matrix by comparing the Functional Connectivity (FC) matrices that describe the pair-wise phase synchronization in a moving window fashion and performing clustering of FCs. Moderate noise can enhance the multistable behavior that is evoked by chaos, resulting in more heterogeneous synchronization patterns, while more intense noise abolishes multistability. In networks composed of nonchaotic nodes, some noise can induce multistability in an otherwise synchronized, nonchaotic network. Finally, we found the same results regardless of the multiplicative or additive nature of noise.
Characterization of Retinal Functionality at Different Eccentricities in a Diurnal Rodent
(Frontiers in Cellular Neuroscience, 2018-12-03) Escobar, María José; Reyes, César; Herzog, Rubén; Araya, Joaquín; Otero, Mónica; Ibaceta, Cristóbal; Palacios, Adrián G.
Although the properties of the neurons of the visual system that process central and peripheral regions of the visual field have been widely researched in the visual cortex and the LGN, they have scarcely been documented for the retina. The retina is the first step in integrating optical signals, and despite considerable efforts to functionally characterize the different types of retinal ganglion cells (RGCs), a clear account of the particular functionality of cells with central vs. peripheral fields is still wanting. Here, we use electrophysiological recordings, gathered from retinas of the diurnal rodent Octodon degus, to show that RGCs with peripheral receptive fields (RF) are larger, faster, and have shorter transient responses. This translates into higher sensitivity at high temporal frequencies and a full frequency bandwidth when compared to RGCs with more central RF. We also observed that imbalances between ON and OFF cell populations are preserved with eccentricity. Finally, the high diversity of functional types of RGCs highlights the complexity of the computational strategies implemented in the early stages of visual processing, which could inspire the development of bio-inspired artificial systems.
Development of Fixed Dose Combination Products Workshop Report: Considerations of Gastrointestinal Physiology and Overall Development Strategy
(Springer, 2019) Hens, Bart; Corsetti, Maura; Bermejo, Marival; Löbenberg, Raimar; González, Pablo M.; Mitra, V; Desai, Divyakant; Murthy Chilukuri, Dakshina; Aceituno, Alexis
The gastrointestinal (GI) tract is one of the most popular and used routes of drug product administration due to the convenience for better patient compliance and reduced costs to the patient compared to other routes. However, its complex nature poses a great challenge for formulation scientists when developing more complex dosage forms such as those combining two or more drugs. Fixed dose combination (FDC) products are two or more single active ingredients combined in a single dosage form. This formulation strategy represents a novel formulation which is as safe and effective compared to every mono-product separately. A complex drug product, to be dosed through a complex route, requires judicious considerations for formulation development. Additionally, it represents a challenge from a regulatory perspective at the time of demonstrating bioequivalence (BE) for generic versions of such drug products. This report gives the reader a summary of a 2-day short course that took place on the third and fourth of November at the Annual Association of Pharmaceutical Scientists (AAPS) meeting in 2018 at Washington, D.C. This manuscript will offer a comprehensive view of the most influential aspects of the GI physiology on the absorption of drugs and current techniques to help understand the fate of orally ingested drug products in the complex environment represented by the GI tract. Through case studies on FDC product development and regulatory issues, this manuscript will provide a great opportunity for readers to explore avenues for successfully developing FDC products and their generic versions.
Pre‐ and postnatal alcohol exposure delays, in female but not in male rats, the extinction of an auditory fear conditioned memory and increases alcohol consumption
(Wiley, 2019) Plaza, Wladimir; Gaschino, Felice; Gutiérrez, Camilo; Santibañez, Nicolás; Estay‐Olmos, Camila; Sotomayor‐Zárate, Ramón; De la Fuente‐Ortega, Erwin; Pautass, Ricardo M.; Haeger, Paola A.
Repeated exposure to alcohol increases retrieval of fear‐conditioned memories, which facilitates, among other factors, the emergence of post‐traumatic stress disorder (PTSD). Individuals with PTSD are more likely to develop alcohol and substance abuse related disorders. We assessed if prenatal and early postnatal alcohol exposure (PAE) increased the susceptibility to retain aversive memories and if this was associated with subsequent heightened alcohol consumption. Pregnant Sprague‐Dawley rats were exposed for 22 hr/day, throughout pregnancy and until postnatal Day 7 to a single bottle of sucralose ‐ sweetened 10% alcohol solution (PAE Group), or to a single bottle of tap water and sucralose (Control Group). Auditory fear conditioning (AFC) was performed in the adolescent offspring at postnatal Day 40. Freezing was measured during acquisition, retention and extinction phases, followed by 3 weeks of free choice alcohol intake. Female, but not male, PAE rats exhibited impaired extinction of the aversive memory, a finding associated with higher levels of 3‐4 Dihidroxyphenylacetic acid (DOPAC) in the nucleus accumbens and heightened alcohol intake, respect to controls. These findings suggest that PAE makes females more vulnerable to long‐term retention of aversive memories, which coexist with heightened alcohol intake. These findings are reminiscent of those of PTSD
Inclusión de salud basada en evidencia en carreras de la salud en Chile y el modelo integrado Metodología de la Investigación Científica-Medicina Basada en Evidencia en la Universidad de Valparaíso
(Elsevier, 2019) Papuzinski, Cristian; Loézar, Cristóbal; Carvajal, Natalia; Vargas, Manuel; Borgeat, Marjorie; Madrid, Eva; Pérez-Bracchiglione, Javier; Arancibia, Marcelo
Introducción: La salud basada en evidencia (SBE) integra el uso de la mejor evidencia, la experiencia clínica y los valores y preferencias del paciente para la toma de decisiones. Su incorporación en las carreras sanitarias de Chile es desconocida. Métodos: Se realizó un estudio de corte transversal para evaluar la incorporación de SBE en los programas de las carreras sanitarias en Chile hasta 2019. Se describe la integración del modelo Metodología de la Investigación Científica (MIC)-Medicina Basada en la Evidencia (MBE) en la Escuela de Medicina de la Universidad de Valparaíso. Resultados: Un total de 49 universidades imparten carreras sanitarias. Un 8,13% incorpora SBE como asignatura explícitamente. Todas incorporan asignaturas que potencialmente incluyen contenidos de SBE. Las carreras de Medicina y Enfermería son las que más incorporan SBE, pero solo una carrera de Medicina incluye SBE como asignatura por más de un semestre. El modelo integrado MIC/MBE (4 semestres), orientado en competencias y centrado en el alumno, involucra el diseno ̃ y ejecución de un protocolo de investigación, así como el análisis crítico de la mejor evidencia, integrado con los valores de los pacientes. Conclusión: La incorporación de SBE como asignatura es muy infrecuente en carreras sanitarias chilenas. Se enfatiza su inclusión transdisciplinaria como asignatura individual desde un modelo que integre la ensenanza ̃ de MIC, sobre todo en universidades estatales.
A Comparison of the Maximum Entropy Principle Across Biological Spatial Scales
(Entropy, 2019-10-15) Cofré, Rodrigo; Herzog, Rubén; Corcoran, Derek; Rosas, Fernando E.
Despite their differences, biological systems at different spatial scales tend to exhibit common organizational patterns. Unfortunately, these commonalities are often hard to grasp due to the highly specialized nature of modern science and the parcelled terminology employed by various scientific sub-disciplines. To explore these common organizational features, this paper provides a comparative study of diverse applications of the maximum entropy principle, which has found many uses at different biological spatial scales ranging from amino acids up to societies. By presenting these studies under a common approach and language, this paper aims to establish a unified view over these seemingly highly heterogeneous scenarios.
The Gaia-ESO Survey: membership probabilities for stars in 32 open clusters from 3D kinematics
(Royal Astronomical Society, 2020) Bayo, Amelia
The Gaia-ESO Survey (GES) observed many open clusters as part of its programme to spectroscopically characterize the various Milky Way populations. GES spectroscopy and Gaia astrometry from its second data release are used here to assign membership probabilities to targets towards 32 open clusters with ages from 1 to 3800 Myr, based on maximum likelihood modelling of the 3D kinematics of the cluster and field populations. From a parent catalogue of 14 398 individual targets, 5032 stars with uniformly determined 3D velocities, Teff, log g, and chemistry are assigned cluster membership with probability >0.9, and with an average probability of 0.991. The robustness of the membership probabilities is demonstrated using independent membership criteria (lithium and parallax) in two of the youngest clusters. The addition of radial velocities improves membership discrimination over proper motion selection alone, especially in more distant clusters. The kinematically selected nature of the membership lists, independent of photometry and chemistry, makes the catalogue a valuable resource for testing stellar evolutionary models and investigating the time evolution of various parameters.
Stability analysis and constraints on interacting viscous cosmology
(American Physical Society, 2020) Motta, Verónica
In this work we study the evolution of a spatially flat Universe by considering a viscous dark matter and perfect fluids for dark energy and radiation, including an interaction term between dark matter and dark energy. In the first part, we analyse the general properties of the Universe by performing a stability analysis and then we constrain the free parameters of the model using the latest and cosmological-independent measurements of the Hubble parameter. We find consistency between the viscosity coefficient and the condition imposed by the second law of the Thermodynamics. The second part is dedicated to constrain the free parameter of the interacting viscous model (IVM) for three particular cases: the viscous model (VM), interacting model (IM), and the perfect fluid case (the concordance model). We report the deceleration parameter to be q0=−0.54+0.06−0.05, −0.58+0.05−0.04, −0.58+0.05−0.05, −0.63+0.02−0.02, together with the jerk parameter as j0=0.87+0.06−0.09, 0.94+0.04−0.06, 0.91+0.06−0.10, 1.0 for the IVM, VM, IM, and LCDM respectively, where the uncertainties correspond at 68\% CL. Worth mentioning that all the particular cases are in good agreement with LCDM, in some cases producing even better fits, with the advantage of eliminating some problems that afflicts the standard cosmological model.
Pharmacological Characterization of 4- Methylthioamphetamine Derivatives
(MDPI, 2020) Guajardo, Fabrizzio G.; Velásquez, Victoria B.; Raby, Daniela; Núñez-Vivanco, Gabriel; Iturriaga-Vásquez, Patricio; España, Rodrigo A.; Miguel, Reyes-Parada; Sotomayor-Zárate, Ramón
Amphetamine derivatives have been used in a wide variety of pathologies because of their pharmacological properties as psychostimulants, entactogens, anorectics, and antidepressants. However, adverse cardiovascular effects (sympathomimetics) and substance abuse problems (psychotropic and hallucinogenic effects) have limited their use. 4-Methylthioamphetamine (MTA) is an amphetamine derivative that has shown to inhibit monoamine uptake and monoamine oxidase. However, the pharmacological characterization (neurochemical, behavioral, and safety) of its derivatives 4-ethylthioamphetamine (ETA) and 4-methylthio-phenil-2-butanamine (MT-But) have not been studied. In the current experiments, we show that ETA and MT-But do not increase locomotor activity and conditioned place preference with respect to MTA. At the neurochemical level, ETA and MT-But do not increase in vivo DA release in striatum, but ETA and MT-But affect the nucleus accumbens bioaccumulation of DA and DOPAC. Regarding cardiovascular effects, the administration of MTA and ETA increased the mean arterial pressure and only ETA significantly increases the heart rate. Our results show that the pharmacological and safety profiles of MTA are modulated by changing the methyl-thio group or the methyl group of the aminoethyl chain.
Cataclysmic variable evolution and the white dwarf mass problem: A Review
(Elsevier, 2020) Zorotovic, Mónica; Schreiber, Matthias R.
Although the theory of cataclysmic variable (CV) evolution is able to explain several observational aspects, strong discrepancies have existed for decades between observations and theoretical predictions of the orbital period distribution, the location of the minimum period, and the space density of CVs. Moreover, it has been shown in the last decade that the average white dwarf (WD) mass observed in CVs is significantly higher than the average mass in single WDs or in detached progenitors of CVs, and that there is an absence of helium-core WDs in CVs which is not observed in their immediate detached progenitors. This highly motivated us to revise the theory of CV formation and evolution. A new empirical model for angular momentum loss in CVs was developed in order to explain the high average WD mass observed and the absence of systems with helium-core WDs. This model seems to help, at the same time, with all of the above mentioned disagreements between theory and observations. Moreover, it also provides us with a very likely explanation for the existence of low-mass WDs without a companion. Here we will review the standard model for CV evolution and the disagreements that have existed for decades between simulations and observations with their possible solutions and/or improvements. We will also summarize the recently confirmed disagreement related to the average WD mass and the fraction of helium-core WDs among CVs, as well as the development of an empirical model that allows us to solve all the disagreements, discussing the physics that could be involved.
Braquiterapia adaptativa guiada por resonancia magnética para el cáncer cervical localmente avanzado: Experiencia del Hospital Carlos Van Buren
(Sociedad Chilena de Obstetricia y Ginecología, 2020) Solis, JA; Olivares, J; Tudela, B; Veillon, G; Perrot, I; Lazcano, G
Introducción y objetivos: El tratamiento estándar para pacientes con cáncer cervical localmente avanzado (CCLA) se basa en radioterapia externa y quimioterapia concomitante seguida de braquiterapia adaptativa guiada por imágenes (BTAGI). El objetivo de este estudio fue describir los resultados del protocolo de BTAGI de resonancia magnética del Servicio de Oncología del Hospital Carlos Van Buren. Métodos: En pacientes con CCLA tratadas con Radioquimioterapia concomitante seguida de BTAGI de resonancia magnética se evaluó la reducción tumoral, parámetros dosimétricos y la toxicidad aguda. Resultados: Se evaluó la reducción tumoral entre el diagnóstico y el momento de la braquiterapia en 34 pacientes. Todas las pacientes completaron el tratamiento de radioterapia externa. Veinticuatro pacientes recibieron 3 sesiones de braquiterapia. Dosis equivalentes totales > 80 Gy se logro en todos los pacientes. Doce pacientes presentaron reducción del volumen tumoral mayor al 70%. La mediana de las dosis equivalentes totales prescritas al D2cc de vejiga fue 73.9 Gy, al recto 65.6 Gy y al intestino fue de 69.1 Gy. Una paciente presento toxicidad gastrointestinal grado ≥ 3. No hubo diferencias estadísticamente significativas al comparar pacientes que recibieron dosis equivalentes totales desde los 85 Gy con las que recibieron menor dosis respecto a toxicidad gastrointestinal (p=0.33) y genitourinaria (p=0.97). Conclusión: La braquiterapia adaptativa guiada por resonancia magnética se puede realizar en el sistema público de salud y cumplir con las recomendaciones internacionales requeridas para el tratamiento estándar del CCLA.
ALMA reveals the molecular gas properties of 5 star-forming galaxies across the main sequence at 3 < z < 3:5.
(European Southern Observatory, 2020) Ibar, Eduardo
We present the detection of CO (5−4) with signal-to-noise ratio (S/N) > 7–13 and a lower CO transition with S/N > 3 (CO (4−3) for four galaxies, and CO (3−2) for one) with the Atacama Large Millimeter/submillimeter Array in bands 3 and 4 in five main-sequence (MS) star-forming galaxies with stellar masses (3–6) × 1010M⊙ at 3 < z < 3.5. We find a good correlation between the total far-infrared luminosity LFIR and the luminosity of the CO (5−4) transition ${L}_{\mathrm{CO}(5-4)}^{{\prime} }$, where ${L}_{\mathrm{CO}(5-4)}^{{\prime} }$ increases with star formation rate (SFR), indicating that CO (5−4) is a good tracer of the obscured SFR in these galaxies. The two galaxies that lie closer to the star-forming MS have CO spectral line energy distribution (SLED) slopes that are comparable to other star-forming populations, such as local submillimeter galaxies and BzK star-forming galaxies; the three objects with higher specific star formation rates have far steeper CO SLEDs, which possibly indicates a more concentrated episode of star formation. By exploiting the CO SLED slopes to extrapolate the luminosity of the CO (1−0) transition and using a classical conversion factor for MS galaxies of ${\alpha }_{\mathrm{CO}}=3.8\,{M}_{\odot}{({\rm{K}}\mathrm{km}{{\rm{s}}}^{-1}{\mathrm{pc}}^{-2})}^{-1}$, we find that these galaxies are very gas-rich, with molecular gas fractions between 60% and 80% and quite long depletion times, between 0.2 and 1 Gyr. Finally, we obtain dynamical masses that are comparable to the sum of stellar and gas mass (at least for four out of five galaxies), allowing us to put a first constraint on the αCO parameter for MS galaxies at an unprecedented redshift.
Study of the Nucleation and Growth Mechanisms of Copper Electrodeposition on Bare and Nitrogen-Doped Reduced Graphene Oxide Modified SnO2:F/glass Substrates
(The Electrochemical Society, 2020) Riveros, G.; León, M.; Ramírez, D.; Hernández, L.; Martín, F.; Romero, R.; Dalchiele, Enrique A.
In this article, the influence of a nitrogen-doped electrochemically reduced graphene oxide layer on the nucleation and growth mechanisms of copper electrodeposition was studied. Thus, copper electrodeposition from an acidic solution was evaluated using two different substrates: fluorine-doped tin oxide (FTO), and fluorine-doped tin oxide covered with a nitrogen-doped reduced graphene oxide layer (FTO/N-ERGO). In both cases, chronoamperometric curves were obtained, which were analyzed and deconvoluted using pre-established models and equations, where the different contribution and nucleation parameters were determined. Field emission scanning electron microscopy (FESEM) images were acquired in order to observe the morphology and verify the nuclei density for each case considered in this study. In the case of copper electrodeposition onto FTO, an instantaneous three-dimensional nucleation was observed, together with a proton reduction reaction. When FTO/N-ERGO was used as a substrate, a new instantaneous two-dimensional nucleation process was observed in addition to the processes previously described. Furthermore, the increased density of active sites and the changes in copper morphology are directly related with the N-ERGO layer, which also increased the kinetic constant for the proton reduction reaction and the nucleation rate per active site during the copper electrodeposition process.
Simultaneous Adsorption of 4,6-Dimethyldibenzothiophene and Quinoline over Nickel and Boron Modified Gamma-Al2O3 Adsorbent
(MDPI, 2020) Ojeda, Juan
The simultaneous adsorption of quinoline and 4,6-dimethyldibenzothiophene over adsorbents, based on alumina modified with boron and nickel under ambient temperature and pressure, was studied. The adsorbents were characterized by BET specific surface area, a potentiometric method for the determination of acid strength, electrophoretic migration, and X-ray diffraction. The results showed that the adsorbent containing nickel had better adsorption capacity than the adsorbent modified with nickel and boron, which was attributed to its greater acidity and ability to generate π-complexation between the adsorbent and the molecules. In terms of selectivity, quinoline was more adsorbed than 4,6-dimethyldibenzothiophene in all systems, due to the basic nature of quinoline. The experimental data in all cases were adjusted by three kinetic models (Yoon–Nelson, Yan and Thomas), and the regression coefficients in all models were close to one. Finally, the values of the kinetic constant obtained by the Thomas model were used to relate the adsorption capacity results. View Full-Text
Efecto de la ingesta de los edulcorantes estevia y D-tagatosa sobre glicemia, péptido C y apetito-saciedad en mujeres con resistencia a la insulina
(Sociedad Chilena De Endocrinología Y Diabetes, 2020) Sambra Vásquez, Verónica; Vega Soto, Claudia; Vicuña Herrera, Isabella; Priken Figueroa, Kathleen; Novik Assael, Victoria; Allendes González, Daniela; Godoy Vega, Paula; Luna Selva, Leticia
Objetivos: Comparar los efectos de la ingesta de una precarga de edulcorantes no nutritivos (ENN) estevia y D-tagatosa, previo a una carga de glucosa oral, sobre la glicemia, péptido C y apetito objetivo y subjetivo en mujeres con resistencia a la insulina (RI). Diseño Experimental: Se usó un diseño de tratamiento cruzado donde cada voluntaria fue su propio control, doble ciego. La 1° prueba correspondió a administración de agua, la 2° y 3° prueba a la administración aleatoria de ENN. En cada prueba, se instaló un catéter intravenoso en la vena antecubital y se tomó muestra de sangre basal. Inmediatamente, bebió 60 ml de agua solo o con 5 g de D-tagatosa o 15.3 mg de estevia. Después de 10 minutos, la voluntaria recibió una carga de glucosa oral, 75 g en la prueba con D-tagatosa y 77.1 g en la prueba con agua o estevia (2.1 g más de glucosa para compensar el aporte calórico de D-tagatosa, 1.5 kcal/g), y se tomó la muestra de sangre “tiempo 0”. Posteriormente, extracciones de sangre a los 30, 60, 90, 120 y 180 minutos. Se evaluó el apetito al término de la prueba. Sujetos y métodos: 33 mujeres (IMC 28.1 ± 3.4 kg/m2, edad 23.4 ± 3.8 años) con RI según HOMA-IR. La glicemia se midió usando un método GOD-PAP, y el Péptido-C, un inmunoensayo enzimático colorimétrico ELISA. Se realizó una evaluación objetiva de apetito, a través del consumo de un buffet. Además, se aplicó una Escala Visual Análoga (EVA) conformada por 8 preguntas para la evaluación subjetiva de apetito. Resultados: En el tiempo 30, la glicemia de los tratamientos control (p=0.004) y estevia (p=0.02) fueron más altas que el tratamiento tagatosa. En el tiempo 90 la concentración de péptido-C fue significativamente más alta en el tratamiento con estevia v/s el control (p=0.035) y en el tiempo 120 estevia presentó un valor significativamente más alto de péptido C al compararlo con tagatosa (p=0.039). El área bajo la curva (ABC) (p=0.005) y ABCincremental (p=0.009) de péptido C fue significativamente mayor tras la ingesta de estevia al comparar con tagatosa y agua (control). Hubo mayor sensación de hambre a los 30 minutos de haber ingerido estevia al compararlo con tagatosa (p=0.014) y agua (p<0.001) y a los 60 minutos post ingesta de estevia (p<0.001) y tagatosa (p=0.02) respecto al control. Mayor reporte de sensación de saciedad una hora después de la ingesta de estevia (p<0.001) y tagatosa (p<0.001) al comparar con agua. Además, mayor “deseo de ingerir un alimento” a los 90 (p=0.00) y 120 (p=0.00) minutos después de haber ingerido estevia sólo al comparar con agua. Conclusión: La tagatosa podría ser beneficiosa para la salud metabólica de una mujer con RI; la estevia, podría promover un efecto insulinotrópico no beneficioso en estas mujeres. A los 60 minutos con ambos ENN hubo más saciedad, pero la estevia a los 120 minutos generó mayor deseo de ingerir alimentos, que no se vio reflejado en el apetito objetivo, puesto que no hubo diferencias en la ingesta de alimentos del buffet ad libitum. Financiamiento: Sociedad Chilena de Endocrinología y Diabetes, proyecto SOCHED 17-10
Involvement of NO in Antinociception of NSAIDS in Murine Formalin Hind Paw Assay
(Thieme, 2020) Noriega, Viviana; Miranda, Hugo F.; Prieto, Juan Carlos; Sotomayor-Zárate, Ramón; Sierralta, Fernando
There are different animal models to evaluate pain among them the formalin hind paw assay which is widely used since some of its events appear to be similar to the clinical pain of humans. The assay in which a dilute solution of formalin is injected into the dorsal hindpaw of a murine produces two ‘phases’ of pain behavior separated by a inactive period. The early phase (Phase I) is probably due to direct activation of nociceptors and the second phase (Phase II) is due to ongoing inflammatory input and central sensitization. Mice were used to determine the potency antinociceptive of piroxicam (1,3,10,and 30 mg/kg), parecoxib (0.3, 1,3,10 and 30 mg/kg), dexketoprofen (3,10,30 and 100 mg/kg) and ketoprofen (3,10,30 and 100 mg/kg). Doseresponse for each NSAIDs were created before and after 5 mg/kg of LNAME i.p. or 5 mg/kg i.p. of 7nitroindazole. A leastsquares linear regression analysis of the log dose–response curves allowed the calculation of the dose that produced 50 % of antinociception (ED50) for each drug. The ED50 demonstrated the following rank order of potency, in the phase I: piroxicam > dexketoprofen > ketoprofen > parecoxib and in the phase II: piroxicam > ketoprofen > parecoxib > dexketoprofen. Pretreatment of the mice with LNAME or 7nitroindazol induced a significant increase of the analgesic power of the NSAIDs, with a significant reduction of the ED50. It is suggested that NO may be involved in both phases of the trial, which means that nitric oxide regulates the bioactivity of NSAIDs.
Nutritional analysis of lluteño maize and fatty acids characterization in modern and ancient samples from northern Chile
(Asociación Interciencia, 2020) Ogalde, Juan Pablo; Arriaza, Bernardo; Cuellar, Mauricio
We present a food quality evaluation of Zea mays L. amylacea from Lluta Valley, northern Chile, a species with important nutritional qualities for historic and current populations in the area. Studies were made of proximal analyses, antioxidant activity, and characterization of the fatty acids fraction. Also, the fatty acids fraction of six ancient maize samples were studied, searching for possible archaeometric markers. The results of the proximal analysis show that the modern Lluteño maize has a high carbohydrates and protein content, low moisture, high ash residue and low antioxidant activity (free radical scavenging). The oleic and linoleic fatty acids show the highest concentrations in Lluteño maize. The presence of omega-6 and omega-9 present in the maize could provide health benefits againstdiseases such as type II diabetes and cardiovascular diseases. Finally, the fatty acid distribution of the ancient maize samplescluster in two categories, one of which was similar to the modern Lluteño maize. Thus, the fatty acid fraction can be considered in the future to investigate the antiquity and evolution of Lluteño maize, and his influence on the health of the local populations.
¿Qué tecnología escojo para mi clase? Percepción de estudiantes de medicina sobre clickers y Kahoot
(Fundación Educación Médica, 2020) Guerra Zuñiga, Maria; Cuevas Lang, Katherine; Segovia Chamorro, Jaime
Introducción: Las nuevas generaciones de estudiantes y las distintas problemáticas de las asignaturas instan a modificar las actividades formativas hacia nuevas formas utilizando tecnologías de la información y la comunicación. Objetivo: Identificar la opinión de los alumnos de primer y segundo año de la carrera de medicina, Universidad de Valparaíso, respecto del uso de un sistema inalámbrico de respuesta (clicker) y Kahoot en el aula. Sujetos y métodos: Estudio cualitativo, fenomenológico. Para la producción de información se realizaron 2 grupos focales con un total de 18 participantes, los cuales se transcribieron según el principio de verbatim. El análisis utilizado fue de contenido. Se efectuó triangulación de la información con técnica de investigadores. Resultados: El uso de clickersy Kahoot se ha valorado positivamente. Se produjo información acerca de las ventajas e inconvenientes de cada una de las tecnologías. Ambas logran focalizar la atención de los estudiantes y aumentan su sensación de disfrute, aprendizaje y calidad de vida al ser estrategias de gamificación. Conclusión: Ambas estrategias tienen la potencialidad de modificar favorablemente los ambientes del aula, con ventajas y limitaciones que deben ser conocidas por los docentes. Es relevante insertarlas dentro de estrategias educativas coherentes para potenciar los procesos de enseñanza-aprendizaje.

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