Detección de microRNAs extracelulares y su potencial como biomarcadores moleculares

RESUMEN Los microRNAs (miRNAs) son moléculas de RNA de 18 a 24 nucleótidos de longitud involucrados en la regulación de la expresión génica a nivel postranscripcional en la célula. En este trabajo analizamos la expresión de miRNAs en muestras de tejido y suero de pacientes con cáncer mamario, y este perfil permite distinguir pacientes con cáncer de mama y mujeres sanas con alta sensibilidad, especificidad y eficiencia. La combinación de dos miRNAs para tejido y tres para suero, usados en conjunto como un solo grupo, eleva significativamente la eficiencia de la prueba, y demuestra que los miRNAs tienen gran potencial como nuevos biomarcadores no invasivos en cáncer de mama. Adicionalmente, se realizó la búsqueda de miRNAs en el protozoario Entamoeba histolytica, por secuenciación profunda, lo que permitió realizar la primera descripción de miRNAs en este parásito. Se identificaron 199 miRNAs exclusivos para este parásito, que servirán de base para el estudio de la regulación génica en E. histolytica y el establecimiento de nuevos biomarcadores para la amibiasis. ABSTRACT MicroRNAs (miRNAs) are 18 to 24 nucleotide-long RNA molecules responsible for the regulation of gene expression at the post-transcriptional level in the cell. In this work, we analyzed the expression of miRNAs in tissue samples and serum of patients with breast cancer and we found that miRNA expression patterns distinguish patients with breast cancer from healthy women with high sensitivity, specificity, and efficiency. The combination of 2 and 3 miRNAs used as a group in tissue and serum respectively, significantly increases the efficiency of the test and shows that miRNAs have potential as novel noninvasive biomarkers in breast cancer detection. Additionally, miRNAs were detected by deep sequence in the protozoan parasite Entamoeba histolytica, which allowed the first description of miRNAs in this parasite. We identified 199 new miRNAs in E. histolytica, which are the base for the study of gene regulation and the establishment of new biomarkers for amoebiasis

Effects of mergers and galaxy interactions at intermediate densities in the SDSS-DR4

Recently, several observational works have provided evidence in favor of a pre-processing of galaxies at moderate environments. These evidences show that the transition of galaxies onto the red-sequence could take place in galaxy groups in the outskirt of clusters or in the infalling populations. Based on the evidence that interacting and merging systems are priviledged found at intermediate densities, we use the SDSSDR4 data to analyse the role of mergers and close galaxy interactions as environmental processes to lead to evolutionary transformations. We explore the properties of galaxy pairs and merging systems at different local and global density environments, comparing them with those of isolated galaxies in an unbiased control sample.Recientemente varios autores han aportado evidencia observacional que sugerir´ıa que las galaxias son pre-procesadas en regiones de densidad intermedia, produciendo una gran transformacion en las mismas. Estos resultados observacionales muestran que la transicion de las galaxias hacia la secuencia roja se producir´ıa en regiones perifericas de los cumulos de galaxias. Por otra parte, existe evidencia tanto teorica como observacional que indicar´ıa que las interacciones y fusiones de galaxias son particularmente frecuentes en estas regiones. En este trabajo analizamos el rol de las interacciones y colisiones de galaxias en regiones de densidad intermedia, utilizando para tal efecto galaxias del cat´alogo SDSS-DR4.Facultad de Ciencias Astronómicas y GeofísicasConsejo Nacional de Investigaciones Científicas y Técnica

Effects of mergers and galaxy interactions at intermediate densities in the SDSS-DR4

Recently, several observational works have provided evidence in favor of a pre-processing of galaxies at moderate environments. These evidences show that the transition of galaxies onto the red-sequence could take place in galaxy groups in the outskirt of clusters or in the infalling populations. Based on the evidence that interacting and merging systems are priviledged found at intermediate densities, we use the SDSSDR4 data to analyse the role of mergers and close galaxy interactions as environmental processes to lead to evolutionary transformations. We explore the properties of galaxy pairs and merging systems at different local and global density environments, comparing them with those of isolated galaxies in an unbiased control sample.Recientemente varios autores han aportado evidencia observacional que sugerir´ıa que las galaxias son pre-procesadas en regiones de densidad intermedia, produciendo una gran transformacion en las mismas. Estos resultados observacionales muestran que la transicion de las galaxias hacia la secuencia roja se producir´ıa en regiones perifericas de los cumulos de galaxias. Por otra parte, existe evidencia tanto teorica como observacional que indicar´ıa que las interacciones y fusiones de galaxias son particularmente frecuentes en estas regiones. En este trabajo analizamos el rol de las interacciones y colisiones de galaxias en regiones de densidad intermedia, utilizando para tal efecto galaxias del cat´alogo SDSS-DR4.Facultad de Ciencias Astronómicas y GeofísicasConsejo Nacional de Investigaciones Científicas y Técnica

Promoting dignified end-of-life care in the emergency department: a qualitative study

Background: Preservation of a dying person’s dignity in the emergency department (ED) is fundamental for the patient, his/her relatives and healthcare professionals. The aim of this study was to explore and interpret physicians’ and nurses’ experiences regarding conservation of dignity in end-of-life care in dying patients in the ED. Methods: A qualitative study based on the hermeneutic phenomenological approach, was carried out in the emergency department of two general hospitals. A total of 16 nurses and 10 physicians participated in the study. Data collection included 12 individual in-depth interviews and 2 focus groups. Results: The findings revealed that two themes represent the practices and proposals for the conservation of dignity in the emergency department: dignified care in hostile surroundings and the design of a system focused on the person’s dignity. Conclusion: Dignifying treatment, redesigning environmental conditions, and reorienting the healthcare system can contribute to maintaining dignity in end-of-life care in the ED

Regions of interest computed by SVM wrapped method for Alzheimer’s disease examination from segmented MRI

Accurate identification of the most relevant brain regions linked to Alzheimer’s disease (AD) is crucial in order to improve diagnosis techniques and to better understand this neurodegenerative process. For this purpose, statistical classification is suitable. In this work, a novel method based on support vector machine recursive feature elimination (SVM-RFE) is proposed to be applied on segmented brain MRI for detecting the most discriminant AD regions of interest (ROIs). The analyses are performed both on gray and white matter tissues, achieving up to 100% accuracy after classification and outperforming the results obtained by the standard t-test feature selection. The present method, applied on different subject sets, permits automatically determining high-resolution areas surrounding the hippocampal area without needing to divide the brain images according to any common template.This work was partly supported by the MICINN under the TEC2012-34306 project and the Consejería de Innovación, Ciencia y Empresa (Junta de Andalucía, Spain) under the Excellence Projects P09-TIC-4530 and P11-TIC-7103. Data collection and sharing for this project was funded by the Alzheimer’s Disease Neuroimaging Initiative (ADNI; National Institutes of Health Grant U01 AG024904).This research was also supported by NIH grants P30 AG010129, K01 AG030514, and the Dana Foundation

Steady-State 3D Trapping and Manipulation of Microbubbles Using Thermocapillary

[EN] An experimental and theoretical study on the 3D trapping and manipulation of microbubbles by means low power laser-induced temperature gradients induced in ethanol by bulk light absorption (¿ 1550 nm) is presented. Two optical fibers were used: One for bubble generation (OFG) and the other for both trapping and manipulation (OFT). Light from a Q-switched pulsed laser (¿ 532 nm and pulse width ¿p 5 ns) propagates in fiber OFG and gets absorbed at silver nanoparticles (AgNPs), previously photodeposited, at the distal end of a fiber optic core, generating the microbubbles. In the fiber OFT, light of low power CW laser was used to trap and manipulate the bubbles by thermocapillary induced by light bulk absorption in ethanol. The microbubble generated on OFG migrates toward the fiber OFT. The equilibrium between the buoyancy force FB, drag force FD and the Marangoni force (also known as thermocapillary force) FM gives rise to a 3D stably trapping and manipulation of the microbubble for the best time to our best knowledge.This work was supported by CONACyT through the grant number A1-S-28440.Muñoz-Pérez, FM.; Ortega-Mendoza, JG.; Padilla-Vivanco, A.; Toxqui-Quitl, C.; Sarabia-Alonso, J.; Ramos-García, R. (2020). Steady-State 3D Trapping and Manipulation of Microbubbles Using Thermocapillary. Frontiers in Physics. 8. https://doi.org/10.3389/fphy.2020.585590

Self-assembled high molecular weight inulin nanoparticles: Enzymatic synthesis, physicochemical and biological properties

Inulin has interesting physicochemical and functional properties, and therefore a wide range of applications in the food and medical industries. It has gained great traction due to its ability to form nanoparticles and its possible application as nanovehicle for drug delivery. In this work, we demonstrated that the enzymatically-synthesized high molecular weight (HMW) inulin forms stable spherical nanoparticles with an average diameter of 112 ± 5 nm. The self-assemblage of HMW inulin nanoparticles is carried out during enzymatic synthesis of the polymer, and become detectable after a certain critical aggregation concentration (CAC) is reached. Both, the CAC and nanoparticle size are influenced by the reaction temperature. These nanoparticles are not toxic for peripheral blood mononuclear cells, at concentrations below 200 μg/mL; no significant prebiotic potential was detected in cultures of 13 probiotic strains. This work contributes to a better understanding of the formation of HMW inulin nanoparticles and their biological properties

Clustering and descendants of MUSYC galaxies at z<1.5

We measure the evolution of galaxy clustering out to a redshift of z~1.5 using data from two MUSYC fields, the Extended Hubble Deep Field South (EHDF-S) and the Extended Chandra Deep Field South (ECDF-S). We use photometric redshift information to calculate the projected-angular correlation function, omega(sigma), from which we infer the projected correlation function Xi(sigma). We demonstrate that this technique delivers accurate measurements of clustering even when large redshift measurement errors affect the data. To this aim we use two mock MUSYC fields extracted from a LambdaCDM simulation populated with GALFORM semi-analytic galaxies which allow us to assess the degree of accuracy of our estimates of Xi(sigma) and to identify and correct for systematic effects in our measurements. We study the evolution of clustering for volume limited subsamples of galaxies selected using their photometric redshifts and rest-frame r-band absolute magnitudes. We find that the real-space correlation length r_0 of bright galaxies, M_r<-21 (rest-frame) can be accurately recovered out to z~1.5, particularly for ECDF-S given its near-infrared photometric coverage. There is mild evidence for a luminosity dependent clustering in both fields at the low redshift samples (up to =0.57), where the correlation length is higher for brighter galaxies by up to 1Mpc/h between median rest-frame r-band absolute magnitudes of -18 to -21.5. As a result of the photometric redshift measurement, each galaxy is assigned a best-fit template; we restrict to E and E+20%Sbc types to construct subsamples of early type galaxies (ETGs). Our ETG samples show a strong increase in r_0 as the redshift increases, making it unlikely (95% level) that ETGs at median redshift z_med=1.15 are the direct progenitors of ETGs at z_med=0.37 with equivalent passively evolved luminosities. (ABRIDGED)Comment: 16 pages, 12 figures, 2 tables, accepted for publication in MNRA

VOLUMEN 14, NÚMERO 28 (1980)

ACTIVIDAD SÍSMICA EN EL DEPARTAMENTO DE SANTANDER. Gómez Padilla, J. A.EVOLUCIÓN GEOLÓGICA DE LA CUENCA PACÍFICA (GEOSINCLINAL DE BOLÍVAR), SECTOR NOROCCIDENTAL DE SURAMÉRICA. Pérez Téllez, G.GEOLOGÍA DE LA CUENCA DEL PUTUMAYO. Govea, R. C., Aguilera, H

VOLUMEN 14, NÚMERO 28 (1980)

ACTIVIDAD SÍSMICA EN EL DEPARTAMENTO DE SANTANDER. Gómez Padilla, J. A.EVOLUCIÓN GEOLÓGICA DE LA CUENCA PACÍFICA (GEOSINCLINAL DE BOLÍVAR), SECTOR NOROCCIDENTAL DE SURAMÉRICA. Pérez Téllez, G.GEOLOGÍA DE LA CUENCA DEL PUTUMAYO. Govea, R. C., Aguilera, H