Search results for "41"
showing 10 items of 3365 documents
Evaluación de la ingesta alimentaria: una reflexión que nos acerque al futuro
2021
El mantenimiento de un óptimo estado de salud es un tema de relevancia que ha llevado a científicos/as y clínicos/as a estudiar, investigar e innovar con el fin de disminuir las brechas y vacíos existentes de conocimiento. Actualmente, la epidemiología nutricional es un área de investigación que cobra cada día más importancia, cuyo objeto de estudio se centra fundamentalmente en el rol de la alimentación en el proceso salud-enfermedad. A partir del estudio del consumo dietético y su relación con las enfermedades crónicas, se ha observado que la dieta es uno de los factores modificables que influyen directamente en la prevención de estas enfermedades1. Además, el interés en estudiar la relac…
Microbiología alimentaria y fenómenos "paranormales" en la historia
2014
A lo largo de la historia han existido fenómenos aparentemente inexplicables cuyos resultados han originado muertes, milagros, juicios por brujería e incluso ganancias y pérdidas de batallas militares. En este artículo se realiza una inspección microbiológica-histórica en donde algunos microorganismos (Claviceps purpurea, Fusarium sporotrichioides, Serratia marcescens y Stachybotrys chartarum), pueden ser los hipotéticos causantes de algunos de estos fenómenos.
Enzymatic Synthesis and Antimicrobial Activity of Oligomer Analogues of Medicinal Biopolymers from Comfrey and Other Species of the Boraginaceae Fami…
2022
This study reports the first enzymatic synthesis leading to several oligomer analogues of poly[3-(3,4-dihydroxyphenyl)glyceric acid]. This biopolymer, extracted from plants of the Boraginaceae family has shown a wide spectrum of pharmacological properties, including antimicrobial activity. Enzymatic ring opening polymerization of 2-methoxycarbonyl-3-(3,4-dibenzyloxyphenyl)oxirane (MDBPO) using lipase from Candida rugosa leads to formation of poly[2-methoxycarbonyl-3-(3,4-dibenzyloxyphenyl)oxirane] (PMDBPO), with a degree of polymerization up to 5. Catalytic debenzylation of PMDBPO using H2 on Pd/C yields poly[2-methoxycarbonyl-3-(3,4-dihydroxyphenyl)oxirane] (PMDHPO) without loss in molecul…
Assessing the Effects of VEGF Releasing Microspheres on the Angiogenic and Foreign Body Response to a 3D Printed Silicone-Based Macroencapsulation De…
2021
Macroencapsulation systems have been developed to improve islet cell transplantation but can induce a foreign body response (FBR). The development of neovascularization adjacent to the device is vital for the survival of encapsulated islets and is a limitation for long-term device success. Previously we developed additive manufactured multi-scale porosity implants, which demonstrated a 2.5-fold increase in tissue vascularity and integration surrounding the implant when compared to a non-textured implant. In parallel to this, we have developed poly(ε-caprolactone-PEG-ε-caprolactone)-b-poly(L-lactide) multiblock copolymer microspheres containing VEGF, which exhibited continued release of bioa…
AGuIX® from bench to bedside-Transfer of an ultrasmall theranostic gadolinium-based nanoparticle to clinical medicine.
2019
International audience; AGuIX® are sub-5 nm nanoparticles made of a polysiloxane matrix and gadolinium chelates. This nanoparticle has been recently accepted in clinical trials in association with radiotherapy. This review will summarize the principal preclinical results that have led to first in man administration. No evidence of toxicity has been observed during regulatory toxicity tests on two animal species (rodents and monkeys). Biodistributions on different animal models have shown passive uptake in tumours due to enhanced permeability and retention effect combined with renal elimination of the nanoparticles after intravenous administration. High radiosensitizing effect has been obser…
Timing and patterns of the ENSO signal in Africa over the last 30 years: insights from normalized difference vegetation index data.
2014
Abstract A more complete picture of the timing and patterns of the ENSO signal during the seasonal cycle for the whole of Africa over the three last decades is provided using the normalized difference vegetation index (NDVI). Indeed, NDVI has a higher spatial resolution and is more frequently updated than in situ climate databases, and highlights the impact of ENSO on vegetation dynamics as a combined result of ENSO on rainfall, solar radiation, and temperature. The month-by-month NDVI–Niño-3.4 correlation patterns evolve as follows. From July to September, negative correlations are observed over the Sahel, the Gulf of Guinea coast, and regions from the northern Democratic Republic of Congo…
Analysis of random walks on a hexagonal lattice
2019
We consider a discrete-time random walk on the nodes of an unbounded hexagonal lattice. We determine the probability generating functions, the transition probabilities and the relevant moments. The convergence of the stochastic process to a 2-dimensional Brownian motion is also discussed. Furthermore, we obtain some results on its asymptotic behavior making use of large deviation theory. Finally, we investigate the first-passage-time problem of the random walk through a vertical straight-line. Under suitable symmetry assumptions we are able to determine the first-passage-time probabilities in a closed form, which deserve interest in applied fields.
Non-Classical Transformation of Benzendiazonium Hydrogen Sulfates. Access to 1,3-Dimethylisochromeno[4,3-c]pyrazol-5(1H)-one, a Potential Benzodiazep…
2013
The compound 2-((1,3-dimethyl-1H-pyrazol-5-yl)(methyl)carbamoyl)benzene-diazonium hydrogen sulfate (10) was reacted with copper sulfate and sodium chloride, in the presence of ascorbic acid as reducing agent, to afford a mixture of the chlorinated epimers 4′-chloro-2,2′,5′-trimethyl-2′,4′-dihydrospiro[isoindoline-1,3′-pyrazol]-3-one (18) and (19), the epimers 4′-hydroxy-2,2′,5′-trimethyl-2′,4′-dihydrospiro[isoindoline-1,3′-pyrazol]-3-one (20) and (21), and N-(1,3-dimethyl-1H-pyrazol-5-yl)benzamide (22). Under the foregoing conditions, diazonium salt 10 affords neither the 2-chloro-N-(1,3-dimethyl-1H-pyrazol-5-yl)-N-methylbenzamide (23) nor the tricyclic derivative 24, the classical products…
La enseñanza del verbo y la actividad metalingüística de los alumnos. Dos investigaciones en aulas de Secundaria
2021
La investigación en Didáctica de la lengua persigue entender las relaciones entre la perspectiva de la enseñanza, la perspectiva del aprendizaje y la de los contenidos trabajados en el aula de Lengua. Este artículo pone el foco en el verbo como contenido gramatical a partir de dos investigaciones centradas en la actividad metalingüística de los alumnos de Educación Secundaria Obligatoria. En la primera, los estudiantes intentan explicar las diferencias entre los tiempos verbales del pasado como paso previo para utilizarlos en la escritura. En la segunda, la reflexión se centra en el subjuntivo a partir de una actividad de pares mínimos que tiene como objetivo comprender cómo conceptualizan …
Previously undiagnosed Reinke edema as a cause of immediate postextubation inspiratory stridor
2015
Reinke edema (RE) is an uncommon lesion of the vocal folds and a potential cause of complications during airway management. We report the case of a woman with previously unknown RE admitted to the intensive care unit who experienced postextubation inspiratory stridor immediately after separation from mechanical ventilation. RE should be considered among causes of postextubation stridor.