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1.
Oxid Med Cell Longev ; 2019: 9719730, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31467641

RESUMEN

Glioblastoma (GBM) is the most common and devastating primary brain tumor. The presence of cancer stem cells (CSCs) has been linked to their therapy resistance. Molecular and cellular components of the tumor microenvironment also play a fundamental role in the aggressiveness of these tumors. In particular, high levels of hypoxia and reactive oxygen species participate in several aspects of GBM biology. Moreover, GBM contains a large number of macrophages, which normally behave as immunosuppressive tumor-supportive cells. In fact, the presence of both, hypoxia and M2-like macrophages, correlates with malignancy and poor prognosis in gliomas. Antioxidant agents, as nutritional supplements, might have antitumor activity. Ocoxin® oral solution (OOS), in particular, has anti-inflammatory and antioxidant properties, as well as antitumor properties in several neoplasia, without known side effects. Here, we describe how OOS affects stem cell properties in certain GBMs, slowing down their tumor growth. In parallel, OOS has a direct effect on macrophage polarization in vitro and in vivo, inhibiting the protumoral features of M2 macrophages. Therefore, OOS could be a feasible candidate to be used in combination therapies during GBM treatment because it can target the highly resilient CSCs as well as their supportive immune microenvironment, without adding toxicity to conventional treatments.


Asunto(s)
Ácido Ascórbico/uso terapéutico , Glioblastoma/tratamiento farmacológico , Macrófagos/metabolismo , Células Madre Neoplásicas/metabolismo , Extractos Vegetales/uso terapéutico , Vitamina B 12/uso terapéutico , Vitamina B 6/uso terapéutico , Animales , Ácido Ascórbico/farmacología , Ácido Fólico , Glioblastoma/patología , Humanos , Ratones , Ratones Desnudos , Ácido Pantoténico , Extractos Vegetales/farmacología , Vitamina B 12/farmacología , Vitamina B 6/farmacología , Sulfato de Zinc
2.
PLoS One ; 10(11): e0142987, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26599583

RESUMEN

Some of the most important effects of global change on coastal marine systems include increasing nutrient inputs and higher levels of ultraviolet radiation (UVR, 280-400 nm), which could affect primary producers, a key trophic link to the functioning of marine food webs. However, interactive effects of both factors on the phytoplankton community have not been assessed for the Mediterranean Sea. An in situ factorial experiment, with two levels of ultraviolet solar radiation (UVR+PAR vs. PAR) and nutrients (control vs. P-enriched), was performed to evaluate single and UVR×P effects on metabolic, enzymatic, stoichiometric and structural phytoplanktonic variables. While most phytoplankton variables were not affected by UVR, dissolved phosphatase (APAEX) and algal P content increased in the presence of UVR, which was interpreted as an acclimation mechanism of algae to oligotrophic marine waters. Synergistic UVR×P interactive effects were positive on photosynthetic variables (i.e., maximal electron transport rate, ETRmax), but negative on primary production and phytoplankton biomass because the pulse of P unmasked the inhibitory effect of UVR. This unmasking effect might be related to greater photodamage caused by an excess of electron flux after a P pulse (higher ETRmax) without an efficient release of carbon as the mechanism to dissipate the reducing power of photosynthetic electron transport.


Asunto(s)
Ecosistema , Fósforo/farmacología , Fitoplancton/efectos de los fármacos , Fitoplancton/efectos de la radiación , Rayos Ultravioleta , Fosfatasa Alcalina/metabolismo , Biomasa , Carbono/análisis , Mar Mediterráneo , Nitrógeno/análisis , Compuestos Orgánicos/análisis , Fósforo/análisis , Fotosíntesis/efectos de los fármacos , Fotosíntesis/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo , Solubilidad , Xantófilas/metabolismo
3.
Chemosphere ; 119: 363-370, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25061941

RESUMEN

A methodology based on headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) determination was developed for the monitoring and evaluation of the removal efficiency of 16 common fragrance allergens and two polycyclic musks in wastewater treatment plants (WWTPs). An experimental design with a full factorial model was applied to evaluate the effects of the experimental parameters on the extraction (e.g., salt content, time and extraction temperature). After determining the optimum conditions (2.4 g NaCl, 45 min at 90 °C), an external calibration was performed and quality parameters of the proposed method were evaluated. Method detection limits in the range of 0.01-1.7 µg L(-1) were obtained. Satisfactory inter-day precision values between 4% and 23% (n=5) were obtained for most compounds. The method was applied to the monitoring of the target analytes in samples from two WWTPs. Seven target compounds were detected at the primary effluent of both plants at µg L(-1) levels. Limonene, linalool and eugenol were quantitatively eliminated during the secondary treatments of both WWTPs, while lilial, benzyl salicylate, galaxolide, and tonalide were still detected at the effluent waters.


Asunto(s)
Alérgenos/análisis , Ácidos Grasos Monoinsaturados/análisis , Perfumes/análisis , Contaminantes Químicos del Agua/análisis , Monoterpenos Acíclicos , Aldehídos/análisis , Benzopiranos/análisis , Ciclohexenos/análisis , Eugenol/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Limoneno , Monoterpenos , Odorantes/análisis , Salicilatos/análisis , Microextracción en Fase Sólida/métodos , Terpenos/análisis , Tetrahidronaftalenos/análisis , Aguas Residuales/análisis
4.
J Sep Sci ; 36(9-10): 1621-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23495009

RESUMEN

This study describes the development of an analytical method based on active collection in a multisorbent Tenax TA/Carbograph 1TD tube, followed by thermal desorption and GC-MS for the determination of 16 volatile organic compounds in air samples. The analyzed compounds include ozone precursors and odor-causing compounds belonging to different chemical families (sulfur- and nitrogen-containing compounds, aldehydes, and terpenes). Two types of sorbents were tested and desorption conditions (temperature, time, and sampling, and desorption flow) were evaluated. External calibration was carried out using the multisorbent bed. Method detection limits in the range 0.2-2.0 µg m(-3) for 1 L samples were obtained. The method was applied for determining the target compounds in air samples from two different wastewater treatment plants. Most compounds were detected and toluene, limonene, and nonanal were found in particularly high concentrations with maximum values of 438, 233, and 382 µg m(-3), respectively.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Odorantes/análisis , Compuestos Orgánicos Volátiles/análisis , Aguas Residuales/análisis , Purificación del Agua/instrumentación
5.
J Chromatogr A ; 1218(30): 4863-8, 2011 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-21411101

RESUMEN

Odorous emissions from wastewater collection systems and treatment facilities affecting quality of life have given local populations reasons to complain for decades. In order to characterise the composition of such malodorous emissions, a method based on headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled to mass spectrometry (GC-MS) has been developed to determine a list of compounds belonging to different chemical families, which have been previously described as potentially responsible for odour complaints, in wastewater matrices. Some parameters affecting the chromatographic behaviour of the target compounds were studied (e.g. splitless time). Experimental conditions affecting the extraction process (temperature, time and salt content) were evaluated by applying a factorial design at two levels. Using a DVB/CAR/PDMS fibre and the optimised HS-SPME conditions, calibration curves were constructed with detection limits in the range of 0.003-0.6 µg L(-1). Recovery values higher than 70% and relative standard deviation values between 5 and 16% (n=5) were obtained for all compounds and found to be satisfactory. In wastewater samples, a decrease in the concentration of the analysed compounds through the different treatments was observed. Most of the target analytes were found in influent samples while only octanal and carvone were detected in samples from the plant effluent.


Asunto(s)
Residuos Industriales/análisis , Odorantes/análisis , Microextracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/análisis , Eliminación de Residuos Líquidos/métodos , Cromatografía de Gases y Espectrometría de Masas , Gases/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Temperatura , Factores de Tiempo , Compuestos Orgánicos Volátiles/aislamiento & purificación
6.
Microb Ecol ; 56(2): 350-63, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18165873

RESUMEN

Knowledge of variations in microbial food web interactions resulting from atmospheric nutrient loads is crucial to improve our understanding of aquatic food web structure in pristine ecosystems. Three experiments mimicking atmospheric inputs at different nitrogen/phosphorus (N/P) ratios were performed in situ covering the seasonal biological succession of the pelagic zone in a high-mountain Spanish lake. In all experiments, abundance, biomass, algal cell biovolume, P-incorporation rates, P-cell quota, and N/P ratio of algae strongly responded to P-enrichment, whereas heterotrophic bacteria remained relatively unchanged. Ciliates were severely restricted when a strong algal exploitation of the available P (bloom growth or storage strategies) led to transient (mid-ice-free experiment) or chronic (late ice-free experiment) P-deficiencies in bacteria. In contrast, maximum development of ciliates was reached when bacteria remained P-rich (N/P < 20) and algae approached Redfield proportions (N/P approximately 16). Evidence of a higher P-incorporation rate supports the proposition that algae and bacteria shifted from a mainly commensalistic-mutualistic to a competitive relationship for the available P when bacterial P-deficiency increased, as reflected by their unbalanced N/P ratio (N/P > 20-24). Hence, the bacterial N/P ratio proved be a key factor to understand the algae-bacteria relationship and microbial food web development. This study not only demonstrates the interdependence of life history strategies, stoichiometric nutrient content, and growth but also supports the use of bacterial N/P thresholds for diagnosing ciliate development, a little-studied aspect worthy of further attention.


Asunto(s)
Bacterias , Cilióforos , Eucariontes , Cadena Alimentaria , Fósforo/metabolismo , Animales , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Cilióforos/crecimiento & desarrollo , Cilióforos/metabolismo , Ecosistema , Eucariontes/crecimiento & desarrollo , Eucariontes/metabolismo , Agua Dulce/microbiología , Agua Dulce/parasitología , Procesos Heterotróficos , Nitrógeno/metabolismo , Estaciones del Año , España
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