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1.
Phys Rev Lett ; 110(8): 085301, 2013 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-23473158

RESUMEN

We show how density dependent gauge potentials can be induced in dilute gases of ultracold atoms using light-matter interactions. We study the effect of the resulting interacting gauge theory and show how it gives rise to novel topological states in the ultracold gas. We find in particular that the onset of persistent currents in a ring geometry is governed by a critical number of particles. The density-dependent gauge potential is also found to support chiral solitons in a quasi-one-dimensional ultracold Bose gas.

2.
Langmuir ; 29(47): 14369-79, 2013 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-24205925

RESUMEN

PEG stearates are extensively used as emulsifiers in many lipid-based formulations. However, the scheme of the principles of the lipid-surfactant polymer interactions are still poorly understood and need more studies. A new phase diagram of a lecithin/PEG 40 monostearate/water system at 30 °C is reported. First, we have characterized the binary PEG 40 monostearate/water system by the determination of the critical micelle concentration value and the viscous properties. Then, the ternary phase behavior and the influence of phase structure on their macroscopic properties are studied by a combination of different techniques, namely, optical microscopy, small-angle X-ray scattering, differential scanning calorimetry, and rheology. The phase behavior is complex, and some samples evolve even at long times. The single monophasic regions correspond to micellar, swollen lamellar, and lamellar gel phases. The existence of extended areas of phase coexistence (hexagonal, cubic, and lamellar liquid crystalline phases) may be a consequence of the low miscibility of S40P in the lecithin bilayer as well as of the segregation of the phospholipid polydisperse hydrophobic chains. The presence of the PEG 40 monostearate has less effect in the transformation to the cubic phase for lecithin than that found in other systems with simple glycerol-based lipids.


Asunto(s)
Glycine max/química , Lecitinas/química , Agua/química , Micelas , Estructura Molecular , Tamaño de la Partícula , Tensión Superficial , Viscosidad
3.
ESMO Open ; 8(1): 100751, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36652782

RESUMEN

Developing better treatments that work for the majority of patients with brain metastasis (BM) is highly necessary. Complementarily, avoiding those therapeutic procedures that will not benefit a specific patient is also very relevant. In general, existing therapies for patients with BM could be improved in terms of molecular stratification and therapeutic efficacy. By questioning the benefit of whole brain radiotherapy as provided nowadays and the lack of biomarkers detecting radioresistance, we identified S100A9 and receptor for advanced glycation end-products (RAGE) as a liquid biopsy biomarker and a potential target for a radiosensitizer, respectively. Both of them are being clinically tested as part of the first comprehensive molecular strategy to personalized radiotherapy in BM.


Asunto(s)
Calgranulina B , Neoplasias , Humanos , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Biomarcadores
4.
Anal Bioanal Chem ; 399(2): 851-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21049268

RESUMEN

The possibilities of different media formed by lecithin/n-butanol (n-BuOH)/water ternary mixtures for the analysis of all-trans-retinol by fluorescence have been studied. Fluorescence intensity of retinol increases in the presence of different types of aggregates formed in these media. Analytical features are good, the detection limit and quantification limit have micrograms per liter levels, and the linear range and sensitivity are appropriate to determine retinol in cosmetic samples. The analysis of retinol in anti-wrinkle creams can be achieved directly without any pretreatment of the sample. The vesicles built up from a biocompatible surfactant (lecithin) in aqueous solution with a low amount of n-BuOH permit an appropriated media for a simple, rapid, and sensitive analytical method. This method has a linear range between 64.1 and 800 µg L(-1), a sensitivity of 202.3 L mg(-1), and a low detection and quantification limit at 19.2 and 64.1 µg L(-1), respectively.


Asunto(s)
1-Butanol/química , Cosméticos/química , Lecitinas/química , Espectrometría de Fluorescencia/métodos , Vitamina A/análisis , Agua/química , Sensibilidad y Especificidad
5.
Adv Drug Deliv Rev ; 169: 79-99, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33321154

RESUMEN

Brain metastasis is emerging as a unique entity in oncology based on its particular biology and, consequently, the pharmacological approaches that should be considered. We discuss the current state of modelling this specific progression of cancer and how these experimental models have been used to test multiple pharmacologic strategies over the years. In spite of pre-clinical evidences demonstrating brain metastasis vulnerabilities, many clinical trials have excluded patients with brain metastasis. Fortunately, this trend is getting to an end given the increasing importance of secondary brain tumors in the clinic and a better knowledge of the underlying biology. We discuss emerging trends and unsolved issues that will shape how we will study experimental brain metastasis in the years to come.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/secundario , Modelos Biológicos , Animales , Humanos , Nanomedicina , Resultado del Tratamiento
6.
J Chem Phys ; 132(24): 244501, 2010 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-20590200

RESUMEN

Hydroxyapatite is the main mineral component of bones and teeth. Fluorapatite, a bioceramic that can be obtained from hydroxyapatite by chemical substitution of the hydroxide ions with fluoride, exhibits lower mineral solubility and larger mechanical strength. Despite the widespread use of fluoride against caries, a reliable technique for unambiguous assessment of fluoridation in in vitro tests is still lacking. Here we present a method to probe fluorapatite formation in fluoridated hydroxyapatite by combining Raman scattering with thermal annealing. In synthetic minerals, we found that effectively fluoride substituted hydroxyapatite transforms into fluorapatite only after heat treatment, due to the high activation energy for this first order phase transition.

7.
Cancer Treat Rev ; 89: 102067, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32682248

RESUMEN

BACKGROUND: Brain metastases are frequent complications in patients with non-small-cell lung cancer (NSCLC) associated with significant morbidity and poor prognosis. Our goal is to give a global overlook on clinical efficacy from immune checkpoint inhibitors in this setting and to review the role of biomarkers and molecular interactions in brain metastases from patients with NSCLC. METHODS: We reviewed clinical trials reporting clinical outcomes of patients with NSCLC with brain metastases as well as publications assessing the tumor microenvironment and the complex molecular interactions of tumor cells with immune and resident cells in brain metastases from NSCLC biopsies or preclinical models. RESULTS: Although limited data are available on immunotherapy in patients with brain metastases, immune checkpoint inhibitors alone or in combination with chemotherapy have shown promising intracranial efficacy and safety results. The underlying mechanism of action of immune checkpoint inhibitors in the brain niche and their influence on tumor microenvironment are still not known. Lower PD-L1 expression and less T CD8+ infiltration were found in brain metastases compared with matched NSCLC primary tumors, suggesting an immunosuppressive microenvironment in the brain. Reactive astrocytes and tumor associated macrophages are paramount in NSCLC brain metastases and play a role in promoting tumor progression and immune evasion. CONCLUSIONS: Discordances in the immune profile between primary tumours and brain metastases underscore differences in the tumour microenvironment and immune system interactions within the lung and brain niche. The characterization of immune phenotype of brain metastases and dissecting the interplay among immune cells and resident stromal cells along with cancer cells is crucial to unravel effective immunotherapeutic approaches in patients with NSCLC and brain metastases.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Animales , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/inmunología , Neoplasias Encefálicas/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/patología , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Humanos , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Activación de Linfocitos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Ensayos Clínicos Controlados Aleatorios como Asunto , Microambiente Tumoral/inmunología
8.
Rev Esp Anestesiol Reanim (Engl Ed) ; 67(1): 39-43, 2020 Jan.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31776014

RESUMEN

Complications induced by general anesthesia (GA) and neuromuscular relaxation (NMR) in anterior mediastinal mass (AMM) resection can be serious, especially when there are signs of compression of the airway or large vessels (dyspnea, orthopnea, etc.) (1). It is preferable to perform the procedure in spontaneous ventilation to avoid respiratory or cardiovascular collapse due to the supine position or to loss of negative intrathoracic pressure with GA and NMR. If the supine position and NMR are unavoidable, procedures should be performed in a step-wise manner, and rescue strategies should be prepared (rescue position, bronchoscope, sternotomy). Correct preoperative evaluation, adequate planning, and a multidisciplinary approach will ensure patient safety. We present the case of a child with a history of severe orthopnea and a diagnosis of AMM and lymphoblastic lymphoma (respiratory arrest and cardiovascular collapse during sedation for lumbar puncture and bone marrow biopsy) that did not respond to medical treatment and required resection surgery under GA with NMR.


Asunto(s)
Anestesia/métodos , Linfoma de Células T/cirugía , Neoplasias del Mediastino/cirugía , Posicionamiento del Paciente/métodos , Biopsia/métodos , Niño , Humanos , Linfoma de Células T/diagnóstico por imagen , Masculino , Neoplasias del Mediastino/diagnóstico por imagen , Sedestación , Tomografía Computarizada por Rayos X
11.
J Colloid Interface Sci ; 514: 415-424, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29278797

RESUMEN

HYPOTHESIS: Aqueous solutions of ionic surfactants allow the exfoliation of graphene, that can be explained considering the adsorption model of ionic surfactants to hydrophobic surfaces. For many years, pyrene has been used as a fluorescent probe because its sensitivity to the micro-environment. The study of pyrene fluorescence in the presence of different graphene dispersions in an ionic surfactant, would improve the knowledge of the graphene-surfactant interactions. EXPERIMENTS: Different dispersions of graphene in sodium dodecylsulfate were prepared at different weight ratios 0.5, 1 and 2%. The dispersions have been studied by Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. The influence of the dispersions on the pyrene fluorescence has been investigated. FINDINGS: The graphene sheets modified by the surfactant quench the fluorescence of pyrene, which depends on the amount of graphene, the concentration of surfactant and the weight ratio. For surfactant concentrations below the critical micelle concentration, the quenching effect is higher as the weight ratio increases. Once this concentration is reached, the fluorescence increases slightly and then levels off. This behavior has been explained by the adsorption model. For a constant surfactant concentration, two straight lines can be observed in the Stern-Volmer plots whose cut-off point is approximately 20 mg L-1 of graphene.

14.
J Colloid Interface Sci ; 298(1): 363-8, 2006 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-16380125

RESUMEN

We have investigated the rheological properties of lamellar liquid crystal formed by nonionic surfactants at low and high surfactant concentrations with a small amount of octyl glucoside and their relationship with the topology of the bilayer. Rheology is a specific signature of each bilayer topology. The decrease in viscosity by increasing the shear rate according to a power law with exponent close to -0.8 was found for the concentrated system of LSB/1-butanol/water and 1% in weight of OG. On the contrary, the decrease in the viscosity by increasing the shear rate for the diluted system is less pronounced with lower exponent values. The rheological data agrees with the presence of vesicles. A special case is the system with benzyl alcohol. The apparent viscosity does not follow the same power law than for alkanols.


Asunto(s)
Glucósidos/química , Cristales Líquidos/química , Membranas Artificiales , Transición de Fase , Tensoactivos/química , 1-Butanol/química , Alcohol Bencilo/química , Viscosidad
15.
J Med Food ; 9(1): 72-6, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16579731

RESUMEN

myo-Inositol hexaphosphate (InsP6) widely occurs in plant seeds. At present, some important benefits of InsP6 for human health have been described. The purpose of this study was to find the best condition for the optimum absorption of orally administered InsP6, evaluated by InsP6 urinary excretion. The influence of different stomach conditions (empty, empty with an alkalinizing agent, and full stomach) on the effects of oral administration of InsP6 and its urinary excretion was investigated in six healthy subjects on an InsP6-poor diet, given 400 mg of calcium/magnesium salt of InsP6 as a single dose. The basal urinary excretion of InsP6 on an InsP6-poor diet (50.91 +/- 15.09 microg) was significantly lower than that found when an InsP6-normal diet was consumed (100.09 +/- 26.42 microg) (P < .05). No differences were observed in the areas under the curve of accumulated excretion at 8 hours among the three different stomach conditions studied, suggesting that the overall InsP6 absorption took place independently of the stomach state (full or fasted) and indicating that the InsP6 absorption also takes place during the intestinal transit. Thus, if InsP6 supplements of vegetal origin are consumed to maintain the optimum InsP6 levels needed for a healthy status, these supplements can be consumed either during or between meals with the same efficacy.


Asunto(s)
Alimentos , Ácido Fítico/farmacocinética , Ácido Fítico/orina , Absorción , Adulto , Dieta , Ayuno , Femenino , Humanos , Absorción Intestinal , Masculino , Persona de Mediana Edad , Ácido Fítico/administración & dosificación
19.
Nat Commun ; 7: 13070, 2016 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-27721438

RESUMEN

Spin chains are paradigmatic systems for the studies of quantum phases and phase transitions, and for quantum information applications, including quantum computation and short-distance quantum communication. Here we propose and analyse a scheme for conditional state transfer in a Heisenberg XXZ spin chain which realizes a quantum spin transistor. In our scheme, the absence or presence of a control spin excitation in the central gate part of the spin chain results in either perfect transfer of an arbitrary state of a target spin between the weakly coupled input and output ports, or its complete blockade at the input port. We also discuss a possible proof-of-concept realization of the corresponding spin chain with a one-dimensional ensemble of cold atoms with strong contact interactions. Our scheme is generally applicable to various implementations of tunable spin chains, and it paves the way for the realization of integrated quantum logic elements.

20.
J Colloid Interface Sci ; 453: 132-141, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25982936

RESUMEN

Nowadays, there is a wide variety of arsenic decontamination processes being adsorption processes the most efficient. In this concern, superparamagnetic iron oxide nanoparticles (SPION) have been proposed as an appropriate system to improve arsenic adsorption from acidic wastewater. The number of mines, the amount of ore processed, and thus the amount of mine (acid) wastewaters have been rapidly increased in recent decades. For this reason, arsenic removal from contaminated water is an important goal to accomplish environmental regulations. It is noteworthy that aggregation of these nanoparticles has been detected as the main difficulty, hindering the promising adsorption. In order to overcome this drawback, it is proposed a system to avoid aggregation based on nanoparticles dispersion into an appropriate supporting material. To this purpose, SPION have been fixed on a cellulosic sponge achieving a decrease of the aggregation state, an increase of the active centers, and consequently, arsenic adsorption increases. Experimental results report a lower aggregation of supported SPION over sponge than the observed in the non supported nanoparticles. At this point, a remarkable improvement in the sponge system adsorption capacity is observed in comparison with superparamagnetic nanoparticles in suspension, reaching adsorption capacities about 2.1 mmol As/g SPION and 12.1 mmol As/g SPION for arsenite and arsenate, respectively at pH 3.8. Then, the developed system not only amends the aggregation problem but also keep their nanoproperties intact, making the system a suitable one for arsenic removal in acidic wastewater treatment.

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