idealidad del dolor Villarreal Barajas, Fernando
Cuadernos de investigación filológica,
12/2022, Volume:
51
Journal Article
Peer reviewed
Este artículo tiene como objeto analizar las convergencias, divergencias e influencias de Arthur Schopenhauer sobre Leopoldo Alas “Clarín” en dos facetas de su carrera literaria e intelectual. Si ...bien la crítica ha estudiado tal influjo, este estudio busca profundizar más al respecto y destacar la función del sufrimiento humano en el credo estético de Alas; su adopción y asimilación parcial. Para elucidar el fundamento de tal temática, se ha analizado la obra periodística de Alas que trata sobre temas filosóficos. Esta herramienta hermeneútica permite establecer los postulados fundamentales del pensamiento filosófico clariniano y determinar los puntos de contacto iniciales. Asimismo, se argumenta que el espiritualismo clariniano de los años noventa presenta una influencia ecléctica, en la cual Schopenhauer ocupa un lugar eminente, en particular su estética y la manifestación del sufrimiento. Este artículo busca determinar el principio artístico de este gran tema clariniano, el cual tiene una función metafísica.
The ability of cancer cells to invade along nerves is associated with aggressive disease and diminished patient survival rates. Perineural invasion (PNI) may be mediated by nerve secretion of glial ...cell line-derived neurotrophic factor (GDNF) attracting cancer cell migration through activation of cell surface Ret proto-oncogene (RET) receptors. GDNF family receptor (GFR)α1 acts as coreceptor with RET, with both required for response to GDNF. We demonstrate that GFRα1 released by nerves enhances PNI, even in the absence of cancer cell GFRα1 expression. Cancer cell migration toward GDNF, RET phosphorylation, and MAPK pathway activity are increased with exposure to soluble GFRα1 in a dose-dependent fashion. Dorsal root ganglia (DRG) release soluble GFRα1, which potentiates RET activation and cancer cell migration. In vitro DRG coculture assays of PNI show diminished PNI with DRG from GFRα1 ⁺/⁻ mice compared with GFRα1 ⁺/⁺ mice. An in vivo murine model of PNI demonstrates that cancer cells lacking GFRα1 maintain an ability to invade nerves and impair nerve function, whereas those lacking RET lose this ability. A tissue microarray of human pancreatic ductal adenocarcinomas demonstrates wide variance of cancer cell GFRα1 expression, suggesting an alternate source of GFRα1 in PNI. These findings collectively demonstrate that GFRα1 released by nerves enhances PNI through GDNF-RET signaling and that GFRα1 expression by cancer cells enhances but is not required for PNI. These results advance a mechanistic understanding of PNI and implicate the nerve itself as a key facilitator of this adverse cancer cell behavior.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Perineural invasion is a form of cancer progression where cancer cells invade along nerves. This behavior is associated with poor clinical outcomes; therefore, it is critical to identify novel ...ligand-receptor interactions between nerves and cancer cells that support the process of perineural invasion. A proteomic profiler chemokine array was used to screen for nerve-derived factors secreted from tissue explants of dorsal root ganglion (DRG), and CCL2 was identified as a lead candidate. Prostate cancer cell line expression of CCR2, the receptor to CCL2, correlated closely with MAPK and Akt pathway activity and cell migration towards CCL2 and DRG. In vitro nerve and cancer coculture invasion assays of perineural invasion demonstrated that cancer cell CCR2 expression facilitates perineural invasion. Perineural invasion is significantly diminished in coculture assays when using DRG harvested from CCL2(-/-) knockout mice as compared with control CCL2(+/+) mice, indicating that CCR2 is required for perineural invasion in this murine model of perineural invasion. Furthermore, 20 of 21 (95%) patient specimens of prostate adenocarcinoma with perineural invasion exhibited CCR2 expression by immunohistochemistry, while just 3 of 13 (23%) lacking perineural invasion expressed CCR2. In summary, nerve-released CCL2 supports prostate cancer migration and perineural invasion though CCR2-mediated signaling.
These results reveal CCL2-CCR2 signaling as a key ligand-receptor mechanism that mediates cancer cell communication with nerves during perineural invasion and highlight a potential future therapeutic target.
In this work, the capacity of wastewater from an inland fishery system in Colombia (Norte de Santander) was tested as culture medium for Chlorella sp. and Scenedesmus sp. Due to insufficient N and P ...concentrations for successful algae growth, the effect of wastewater replenishment with NO3, PO4, and Na2CO3 or NaHCO3 as a carbon source was analyzed using a three-factor nonfactorial response surface design. The results showed that the addition of NaNO3 (0.125 g/L), K2HPO4 (0.075 g/L), KH2PO4 (0.75 g/L), and NaHCO3 (0.5 and 2 g/L for Chlorella sp. and Scenedesmus sp. respectively) significantly increased the biomass of Chlorella sp. (0.87 g/L) and Scenedesmus sp. (0.83 g/L). Although these results show that the addition of other nutrients is not necessary (Na, Mg, SO4, Ca, etc.), it is still essential to determine the quality of the biomass produced in terms of its application as a feed supplement for fish production.
Although microalgae have potential as a raw material for biodiesel production it is necessary to increase biomass and lipids productivity. One way to achieve this goal is the implementation of ...mixotrophic cultures and the regulation of carbon/nitrogen ratio. The present work aims to improve the productivity of biomass and lipids in Chlorella vulgaris UTEX 1803 using waste glycerol from biodiesel production (1, 5 and 10% v/v) and sodium acetate (5, 10 and 20 mM) as carbon sources, with modification of the initial concentration of nitrogen (1.02, 1.47 and 2.94 mM de NaNO sub(3)). All experiments were performed at 23 + or - 1degreesC, with light-dark cycles of 12:12h during five days. In biomass production, a significant increase was achieved (80% higher that cultures without modification). Lipid productivities were also found 2.83 and 3.5 times greater than control. Results show the possibility of increasing the production of biomass and lipids by applying the carbon/nitrogen ratio, using waste glycerol. This opens up great possibilities for the re-use of this residue, thus increasing the sustainability of the process in general. Also, it has been proved that -due to its low cost- carbon/nitrogen ratio using sodium acetate is an interesting alternative.Original Abstract: A unque las microalgas poseen potencial como materia prima para la produccion de biodiesel, es necesario aumentar la productividad de biomasa y lipidos. Una forma de lograrlo es con la implementacion de cultivos mixotroficos y la regulacion de la relacion carbono/nitrogeno. El presente trabajo tiene como objetivo mejorar la productividad de biomasa y lipidos en Chlorella vulgaris UTEX 1803 usando como fuentes de carbono glicerol residual de la produccion de biodiesel (1, 5 y 10% v/v) y acetato de sodio (5, 10 y 20 mM), y modificando la concentracion de nitrogeno inicial (1.02, 1.47 y 2.94 mM de NaNO sub(3)). Las condiciones de cultivo fueron: 23 + or - 1degreesC, ciclos luz-oscuridad 12: 12h durante periodos establecidos de cinco dias. Se logro un aumento significativo en la produccion de biomasa (80% mayor que cultivos sin modificacion). Se encontraron productividades lipidicas 2.83 y 3.5 veces mayores que el control. Los resultados demuestran la posibilidad de aumentar la produccion de biomasa y lipidos aplicando la relacion carbono/nitrogeno empleando el glicerol residual como posibilidad de reciclo de este residuo, aumentado asi la sostenibilidad del proceso en general; se determino ademas que el acetato de sodio puede ser utilizado como una alternativa economica para controlar la relacion carbono/nitrogeno.
El objetivo del presente estudio fue evaluar la viabilidad del uso de glicerina como fuente de carbono, usando algas inmovilizadas para la producción de metabolitos como carbohidratos, proteínas y ...lípidos. Se encontró, mediante el uso de análisis estadístico, que la acumulación de hidratos de carbono se favorece con concentraciones de glicerina de 3-5% (v/v) y 0,37 (g/L) de nitrógeno. La deposición de lípidos, se favorece con una concentración de 3% (v/v) de glicerina y 0,04 (g/L) de nitrógeno; Por otro lado, las proteínas se favorecen con mayores concentraciones de glicerina (5% v/v), y una concentración de nitrógeno similar a la utilizada para hidratos de carbono.
En los últimos años se ha vuelto cada vez más frecuente el uso de medios de cultivo basados en fuentes de fósforo, nitrógeno y microelementos como alternativa a los medios tradicionales. Por lo ...tanto, en este trabajo se diseñaron dos medios de cultivo mixotróficos con diferentes concentraciones de nitrato de sodio, fosfato de potasio, acetato de sodio y carbonato de amonio (estos últimos como fuente de carbono), a fin de evaluar la producción de biomasa y proteínas a partir de la microalga Chlorella vulgaris. Se realizaron diagramas de Pareto y superficies de respuesta a fin de conocer la influencia de las variables de estudio sobre la producción de proteínas. Los resultados mostraron que las mayores producciones de biomasa (3,72 para el cultivo con acetato y 2,17 g/L para el cultivo con carbonato) están directamente relacionadas con el nitrato de sodio (1,96 mM) y el fosfato de potasio (2,11 mM). Además, los máximos porcentajes de proteínas obtenidos fueron 60 % y 34 % para los cultivos con acetato y carbonato, respectivamente, ambos con 2,94 mM de nitrato de sodio. Finalmente, con base en el diagrama de Pareto obtenido, se encontró que para el medio de cultivo con acetato no existieron variables significativas que influyeran sobre la producción de proteínas, mientras que, en el medio de cultivo con carbonato, el nitrato de sodio y el fosfato de potasio influyeron significativamente en la producción de este metabolito.
This work studied the improvement of biomass and carbohydrate (glucose and xylose) lab-scale productivity in Chlorella vulgaris UTEX 1803 through the use of the carbon/nitrogen ratio. In order to do ...so, mixotrophic cultures were made by the modification of initial concentration of CH sub(3)COONa (5, 10 and 20 mM) and NaNO sub(3) (0.97, 1.94 and 2.94 mM). All treatments were maintained at 23 plus or minus 1 degree C, with light/dark cycles of 12h: 12h for 5 days. It was found that in addition to the carbon/nitrogen ratio, time also influences the concentration of biomass and carbohydrates. The treatment containing 10 mM acetate: 1.94 mM nitrate, reached a concentration of 0.79 g/L of biomass, 76.9 mu g/mL of xylose and 73.7 mu g/mL of glucose in the fifth day. However, the treatment containing 20 mM acetate: 0.97 mM nitrate produced 1.04 g/L of biomass, 78.9 mu g/mL of xylose and 77.2 mu g/mL of glucose in the third day, while in the same day the treatment containing 0 mM acetate: 2.94 mM nitrate, produced 0.55 g/L of biomass, 40.2 mu g/mL of xylose and 31.3 mu g/mL of glucose. The use of carbon/nitrogen ratios improved biomass productivity (from 0.55 to 1.04 g/L) as well as xylose (from 40.2 to 78.9 mu g/mL) and glucose (from 31.3 to 77.2 mu g/mL) concentration, representing an improvement of up to two times the production of both biomass and carbohydrates in only 3 days of culture.
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