It is now well-established that dysregulation of the tricarboxylic acid (TCA) cycle enzymes succinate dehydrogenase, fumarate hydratase, and isocitrate dehydrogenase leads to the abnormal cellular ...accumulation of succinate, fumarate, and 2-hydroxyglutarate, respectively, which contribute to the formation and malignant progression of numerous types of cancers. Thus, these metabolites, called oncometabolites, could potentially be useful as tumour-specific biomarkers and as therapeutic targets. For this reason, the development of analytical methodologies for the accurate identification and determination of their levels in biological matrices is an important task in the field of cancer research. Currently, hyphenated gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) techniques are the most powerful analytical tools in what concerns high sensitivity and selectivity to achieve such difficult task. In this review, we first provide a brief description of the biological formation of oncometabolites and their oncogenic properties, and then we present an overview and critical assessment of the GC-MS and LC-MS based analytical approaches that are reported in the literature for the determination of oncometabolites in biological samples, such as biofluids, cells, and tissues. Advantages and drawbacks of these approaches will be comparatively discussed. We believe that the present review represents the first attempt to summarize the applications of these hyphenated techniques in the context of oncometabolite analysis, which may be useful to new and existing researchers in this field.
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•The cellular overproduction of oncometabolites is associated with may type of cancers.•Oncometabolites could potentially be useful as tumour-specific biomarkers and/or therapeutic targets.•We provide a brief description of the biological formation of oncometabolites and their oncogenic properties.•We perform an overview of the GC-MS and LC-MS methods available to determine oncometabolites in biological samples.
ABSTRACT
We present QUIJOTE intensity and polarization maps in four frequency bands centred around 11, 13, 17, and 19 GHz, and covering approximately 29 000 deg2, including most of the northern sky ...region. These maps result from 9000 h of observations taken between May 2013 and June 2018 with the first QUIJOTE multifrequency instrument (MFI), and have angular resolutions of around 1°, and sensitivities in polarization within the range 35–40 µK per 1° beam, being a factor ∼2–4 worse in intensity. We discuss the data processing pipeline employed, and the basic characteristics of the maps in terms of real space statistics and angular power spectra. A number of validation tests have been applied to characterize the accuracy of the calibration and the residual level of systematic effects, finding a conservative overall calibration uncertainty of 5 per cent. We also discuss flux densities for four bright celestial sources (Tau A, Cas A, Cyg A, and 3C274), which are often used as calibrators at microwave frequencies. The polarization signal in our maps is dominated by synchrotron emission. The distribution of spectral index values between the 11 GHz and WMAP 23 GHz map peaks at β = −3.09 with a standard deviation of 0.14. The measured BB/EE ratio at scales of ℓ = 80 is 0.26 ± 0.07 for a Galactic cut |b| > 10°. We find a positive TE correlation for 11 GHz at large angular scales (ℓ ≲ 50), while the EB and TB signals are consistent with zero in the multipole range 30 ≲ ℓ ≲ 150. The maps discussed in this paper are publicly available.
En el presente artículo profundizaremos en los principales hallazgos que evidencian el potencial de diferentes compuestos cannabinoides como fármacos antiepilépticos y el estado actual de la ...legislación vigente en cuanto a lo concerniente a la utilización y cultivo de la planta de cannabis en Colombia, con miras a vislumbrar los retos que enfrenta la investigación y producción de fármacos antiepilépticos derivados de cannabis en nuestro país. Adicionalmente abordaremos temas como los retos que actualmente tiene la legalización de este tipo de fármacos derivados de cannabis en nuestro país. Ciertamente creemos que el avance en este campo no solo es cuestión del marco jurídico vigente sino también de su oportuna divulgación y el trabajo mancomunado del desarrollo industrial y entidades gubernamentales para el establecimiento claro de la normativa requerida para desarrollar y comercializar medicamentos derivados de cannabis en Colombia.
INTRODUCCIÓN: Existe el concepto social que “saber” transforma al experto en un buen docente, peroprobablemente “saber” es la condición básica para ejercer la docencia. El objetivo de este trabajo es ...analizarlas características que superan al conocimiento para transformarse en un buen docente enriquecido por laVisión Ignaciana de esta actividad.MATERIAL Y MÉTODO: Para elaborar este informe se trabajó sobre tres documentos de alto impacto ennuestro hacer: 1) el paradigma Paradigma Ledesma – Kolvenbach; 2) Constitución apostólica sobre lasUniversidades Católicas de SS Juan Pablo II y 3) La pedagogía Ignaciana.DISCUSIÓN Y CONCLUSIÓN: Ser buen docente, parte del saber especifico, pero es mucho más quesimplemente saber, implica compromiso con la realidad y la capacidad de crear espacios, que favorecen laapropiación crítica del conocimiento y la actitud de búsqueda permanente por parte de la comunidadestudiantil
We investigate the quantum entanglement of the three modes associated with the three-photon states obtained by triple-photon generation in a phase-matched third-order nonlinear optical interaction. ...Although the second-order processes have been extensively dealt with, there is no direct analogy between the second and third-order mechanisms. We show, for example, the absence of quantum entanglement between the quadratures of the three modes in the case of spontaneous parametric triple-photon generation. However, we show robust, seeding-dependent, genuine triple-photon entanglement in the fully seeded case.
Estimamos índices de sentimiento a nivel regional y nacional utilizando información en formato de texto del Programa Trimestral de Entrevistas a Directivos, empleada para la elaboración del Reporte ...sobre las Economías Regionales del Banco de México, referente a los factores que los entrevistados consideran que afectaron, afectan o pudieran afectar la actividad económica en su sector o entidad federativa. Estos índices, estimados con información de los programas de entrevistas trimestrales llevados a cabo entre enero de 2016 y enero de 2021, son posteriormente asociados con diferentes indicadores de actividad económica regional y nacional publicados por el INEGI, obteniéndose correlaciones positivas y estadísticamente significativas entre los índices de sentimiento y algunos indicadores de actividad económica. Dado que estos índices de sentimiento pueden obtenerse con mayor rapidez que la mayoría de los indicadores tradicionales de actividad económica aquí analizados, el trabajo destaca la relevancia de la información en formato de texto contenida en el Programa Trimestral de Entrevistas a Directivos para complementar la obtenida con indicadores tradicionales.
A partir de nanocajas metálicas de doble pared con un monoporo (DWSPNb) sintetizadas por efecto Kirkendall y reemplazo galvánico, se propone una plataforma multifuncional nanoestructurada con ...capacidad de liberación secuencial de agentes moleculares para uso terapéutico. La evaluación de la plataforma propuesta se hizo mediante cálculo numérico basado en las dimensiones, morfología y composición de las nanocajas sintetizadas. Para las combinaciones de dos moléculas farmacológicas de interés, se determinaron los coeficientes de difusión en función de la distancia a las paredes de la nanocaja y la concentración. La simulación realizada para la liberación de las dos moléculas de la cavidad interna a través del nanocanal formado entre las dos paredes de la nanocaja evidenció la cinética secuencial requerida. Este comportamiento permite programar entregas controladas en tiempo y lugar para reducir la resistencia a los fármacos duales y, consecuentemente, optimizar la dosis necesaria y evitar los efectos secundarios derivados. La composición metálica convirtió la nanocaja en una nanoantena optotérmica, lo que permite controlar la liberación y entrega de la carga molecular a través de polímeros sensibles a la temperatura, además de su uso potencial para tratamientos fotodinámicos y diagnósticos por imagen.
The cosmic microwave background (CMB) radiation data obtained by different experiments contain, besides the desired signal, a superposition of microwave sky contributions. Using a wavelet ...decomposition on the sphere, we present a fast and robust method to recover the CMB signal from microwave maps. We present an application to the Wilkinson Microwave Anisotropy Probe (WMAP) polarization data, which shows its good performance, particularly in very polluted regions of the sky. The applied wavelet has the advantages that it requires little computational time in its calculations, it is adapted to the healpix pixelization scheme and it offers the possibility of multiresolution analysis. The decomposition is implemented as part of a fully internal template fitting method, minimizing the variance of the resulting map at each scale. Using a χ2 characterization of the noise, we find that the residuals of the cleaned maps are compatible with those expected from the instrumental noise. The maps are also comparable to those obtained from the WMAP team, but in our case we do not make use of external data sets. In addition, at low resolution, our cleaned maps present a lower level of noise. The E-mode power spectrum
is computed at high and low resolutions, and a cross-power spectrum
is also calculated from the foreground reduced maps of temperature given by WMAP and our cleaned maps of polarization at high resolution. These spectra are consistent with the power spectra supplied by the WMAP team. We detect the E-mode acoustic peak at ℓ∼ 400, as predicted by the standard ΛCDM model. The B-mode power spectrum
is compatible with zero.
Taurine is considered the most abundant free amino acid in the brain. Even though there are endogenous mechanisms for taurine production in neural cells, an exogenous supply of taurine is required to ...meet physiological needs. Taurine is required for optimal postnatal brain development; however, its brain concentration decreases with age. Synthesis of taurine in the central nervous system (CNS) occurs predominantly in astrocytes. A metabolic coupling between astrocytes and neurons has been reported, in which astrocytes provide neurons with hypotaurine as a substrate for taurine production. Taurine has antioxidative, osmoregulatory, and anti-inflammatory functions, among other cytoprotective properties. Astrocytes release taurine as a gliotransmitter, promoting both extracellular and intracellular effects in neurons. The extracellular effects include binding to neuronal GABA
A
and glycine receptors, with subsequent cellular hyperpolarization, and attenuation of
N
-methyl-D-aspartic acid (NMDA)-mediated glutamate excitotoxicity. Taurine intracellular effects are directed toward calcium homeostatic pathway, reducing calcium overload and thus preventing excitotoxicity, mitochondrial stress, and apoptosis. However, several physiological aspects of taurine remain unclear, such as the existence or not of a specific taurine receptor. Therefore, further research is needed not only in astrocytes and neurons, but also in other glial cells in order to fully comprehend taurine metabolism and function in the brain. Nonetheless, astrocyte’s role in taurine-induced neuroprotective functions should be considered as a promising therapeutic target of several neuroinflammatory, neurodegenerative and psychiatric diseases in the near future. This review provides an overview of the significant relationship between taurine and astrocytes, as well as its homeostatic and neuroprotective role in the nervous system.
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