90 research outputs found
Lipid Raft Size and Lipid Mobility in Non-raft Domains Increase during Aging and Are Exacerbated in APP/PS1 Mice Model of Alzheimer's Disease. Predictions from an Agent-Based Mathematical Model
A connection between lipid rafts and Alzheimer's disease has been studied during the last decades. Mathematical modeling approaches have recently been used to correlate the effects of lipid composition changes in the physicochemical properties of raft-like membranes. Here we propose an agent based model to assess the effect of lipid changes in lipid rafts on the evolution and progression of Alzheimer's disease using lipid profile data obtained in an established model of familial Alzheimer's disease. We have observed that lipid raft size and lipid mobility in non-raft domains are two main factors that increase during age and are accelerated in the transgenic Alzheimer's disease mouse model. The consequences of these changes are discussed in the context of neurotoxic amyloid β production. Our agent based model predicts that increasing sterols (mainly cholesterol) and long-chain polyunsaturated fatty acids (LCPUFA) (mainly DHA, docosahexaenoic acid) proportions in the membrane composition might delay the onset and progression of the disease.This work was funded by research grants from BIO2014-54411-C2-2-R and SAF2014-52582-R from Ministerio de Economía y Competitividad (MINECO, Spain). GSR acknowledges the support of Obra Social La Caixa-Fundación CajaCanarias that granted him a Posgraduate Fellowship at the Universidad de La Laguna.Peer reviewedPeer Reviewe
Co-evaluation in a problem solving practice in a bioscience subject
La co-evaluación o evaluación entre pares es reconocida como una actividad que
estimula el papel activo del alumnado en el proceso de aprendizaje. Los estudiantes
tienen la oportunidad de revisar el trabajo de su compañeros de clase frente a su propia
evaluación lo que permite una reflexión sobre su proceso de aprendizaje. Como
resultado, son capaces de reorientar sus propias estrategias de apredizaje. En esta
comunicación se muestran los resultados de un ejercicio de co-evaluación llevado a
cabo con un grupo de 90 estudiantes del Grado en Biología de la Universidad de La
Laguna en el marco de un un curso general de Bioquímica con contenidos en cinética
enzimática. Aunque ninguno realizó antes co-evaluaciones, los resultados muestran
que las correcciones realizadas fueron correctas y consistentes con las de los profesoresCo-evaluation or evaluation between peers is gaining ground as a drive for the
active role of the student in the learning process. Students are given the opportunity
to review their classmate’s work, facing their own evaluation and thus reflecting of
their learning process. As a result they are able to reorient their own strategy. In
this communication we show the results of a co-evaluation exercise carried out
with a group of 90 students of a degree in Biology, within a general course of
biochemistry containing enzymology issues. Although none of them have done
co-evaluations before, results show that the corrections made were refined and
consistent with those made by teacher
Modeling of leishmaniasis infection dynamics: novel application to the design of effective therapies
<p>Abstract</p> <p>Background</p> <p>The WHO considers leishmaniasis as one of the six most important tropical diseases worldwide. It is caused by parasites of the genus <it>Leishmania </it>that are passed on to humans and animals by the phlebotomine sandfly. Despite all of the research, there is still a lack of understanding on the metabolism of the parasite and the progression of the disease. In this study, a mathematical model of disease progression was developed based on experimental data of clinical symptoms, immunological responses, and parasite load for <it>Leishmania amazonensis </it>in <it>BALB/c </it>mice.</p> <p>Results</p> <p>Four biologically significant variables were chosen to develop a differential equation model based on the GMA power-law formalism. Parameters were determined to minimize error in the model dynamics and time series experimental data. Subsequently, the model robustness was tested and the model predictions were verified by comparing them with experimental observations made in different experimental conditions. The model obtained helps to quantify relationships between the selected variables, leads to a better understanding of disease progression, and aids in the identification of crucial points for introducing therapeutic methods.</p> <p>Conclusions</p> <p>Our model can be used to identify the biological factors that must be changed to minimize parasite load in the host body, and contributes to the design of effective therapies.</p
Relevancia e impacto del perfil formativo de los estudiantes de nuevo ingreso en los grados en ciencias sobre su progreso y continuidad: un modelo predictivo
La Facultad de Ciencias de la Universidad de La Laguna lanzó, en el curso
2016/17, un Plan de detección y atención de deficiencias formativas en Biología,
Física, Geología, Matemáticas y Química para el alumnado de nuevo ingreso en
el centro. Esta iniciativa estuvo motivada por la constatación de que entre las
diversas variables que condicionan el rendimiento académico en la universidad,
la que muestra una correlación más significativa es la del rendimiento en la fase
preuniversitaria. En este trabajo se hace un diagnóstico de la situación en la que
se encuentra el alumnado de nuevo ingreso de la Facultad de Ciencias (Grados
en Biología, Ciencias Ambientales, Física, Matemáticas y Química) y de la efec-
tividad de algunas de las medidas que tradicionalmente se han venido desarro-
llando para paliar los déficits formativos detectados, y se propone un modelo
estadístico predictivo del rendimiento del alumnado en el primer cuatrimestre de
universidad en función de su rendimiento previo, finalizando con la propuesta de
una serie de políticas y acciones que desde el nivel local (centro y departamento)
al institucional (universidad) habría que acometer si se quiere dar una respuesta
eficaz al problema.The School of Sciences of the University of La Laguna launched, in the academic
year 2016/17, a Plan for the detection and attention of training deficiencies in
Biology, Physics, Geology, Mathematics and Chemistry for incoming freshmen. This
initiative is motivated by the observation that among the various variables that
condition the academic performance in the university, the one which correlates
most significantly is the performance in the pre-university phase. In this work, a
diagnosis is made of the situation in which the newly admitted students to the School
of Sciences (degrees in Biology, Environmental Sciences, Physics, Mathematics
and Chemistry) are, and of the effectiveness of some of the measures that have
been developed so far to alleviate the learning deficits detected. Also, a predictive
statistical model of student performance in the first semester of university based
on their previous performance is proposed. The paper ends by suggesting a series
of policies and actions that from the local level (center and department) to the
institutional one (university) would have to be undertaken in order to effectively
respond to the problems detected
α-Glucosidase and α- amylase inhibition potentials of ten wild Mexican species of Verbenaceae
Purpose: To evaluate the inhibitory activity of 10 wild Verbenaceae species from Mexico against α- glucosidase and α-amylase.Methods: Ethanol leaf extracts of 10 Verbenaceae species from Mexico were prepared. The inhibitory activity of the extracts against α-glucosidase and α-amylase was evaluated using enzymatic protocols. At least four serial diluted concentrations of each extract was used to calculate the half-maximal inhibitory concentration (IC50).Results: The 10 evaluated Verbenaceae species showed high α-glucosidase inhibition activity, but a low inhibitory effect on α-amylase. Aloysia gratissima (IC50 = 0.122 mg/mL), Verbena carolina (IC50 = 0.112 mg/mL), Bouchea prismatica (IC50 = 0.122 mg/mL), Verbena menthiflora (IC50 = 0.071mg/mL) and Priva mexicana (IC50 = 0.032 mg/mL) exhibited the strongest inhibitory activities against α- glucosidase.Conclusion: All the Verbenaceae species studied possess α-glucosidase inhibitory effect, with P. mexicana being the one with the strongest activity. These findings demonstrate the highs potential of these species as a source of natural antihyperglycemic agents for type 2 diabetes therapy.Keywords: Hyperglycemic, Diabetes, α-Glucosidase, α-Amylase Verbenaceae, Aloysia gratissima, Bouchea prismatica, Priva mexican
Modelling and Analysis of Central Metabolism Operating Regulatory Interactions in Salt Stress Conditions in a L-Carnitine Overproducing E. coli Strain
Based on experimental data from E. coli cultures, we have devised a mathematical model in the GMA-power law formalism that describes the central and L-carnitine metabolism in and between two steady states, non-osmotic and hyperosmotic (0.3 M NaCl). A key feature of this model is the introduction of type of kinetic order, the osmotic stress kinetic orders (gOSn), derived from the power law general formalism, which represent the effect of osmotic stress in each metabolic process of the model
An Eccentric Massive Jupiter Orbiting a Subgiant on a 9.5-day Period Discovered in the <i>Transiting Exoplanet Survey Satellite</i> Full Frame Images
We report the discovery of TOI-172 b from the Transiting Exoplanet Survey Satellite (TESS) mission, a massive hot Jupiter transiting a slightly evolved G star with a 9.48-day orbital period. This is the first planet to be confirmed from analysis of only the TESS full frame images, because the host star was not chosen as a two-minute cadence target. From a global analysis of the TESS photometry and follow-up observations carried out by the TESS Follow-up Observing Program Working Group, TOI-172 (TIC 29857954) is a slightly evolved star with an effective temperature of T eff = 5645 ± 50 K, a mass of M ⋆ = {1.128}-0.061+0.065 M ⊙, radius of R ⋆ = {1.777}-0.044+0.047 R ⊙, a surface gravity of log g ⋆ = {3.993}-0.028+0.027, and an age of {7.4}-1.5+1.6 {Gyr}. Its planetary companion (TOI-172 b) has a radius of R P = {0.965}-0.029+0.032 R J, a mass of M P = {5.42}-0.20+0.22 M J, and is on an eccentric orbit (e={0.3806}-0.0090+0.0093). TOI-172 b is one of the few known massive giant planets on a highly eccentric short-period orbit. Future study of the atmosphere of this planet and its system architecture offer opportunities to understand the formation and evolution of similar systems
4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica
Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil.
El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país.
La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica.
Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas
Introducing Systems Biology to Bioscience students through mathematical modelling. A practical module
Systems Biology, one of the current approaches to the understanding of living things, aims to understand the behaviour of living systems through the creation of mathematical models that integrate the available knowledge of the system’s component parts and the relations among them. Accordingly, model building should play a central part in any biology degree program. One difficulty that we face when confronted with this task, however, is that the mathematical background of undergraduate students is very often deficient in essential concepts required for dynamic mathematical modelling. In this practical module, students are introduced to the basic techniques of mathematical modelling and computer simulation from a Systems Biology perspective
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