349 research outputs found
New Vehiculation Systems of Mometasone Furoate for the Treatment of Inflammatory Skin Diseases
A pre-formulation study was carried out to obtain liposomal formulations of mometasone furoate as an alternative system to marketed forms of corticosteroid for the treatment of inflammatory skin lesions. Mometasone furoate was loaded in glycerosomes and glyceroethosomes, which were also modified with hyaluronic acid (glyceroethohyalurosomes). Vesicles were designed, elaborated, and characterized, and their biocompatibility, efficacy against oxidative stress and skin lesions were assessed in vitro, in human epidermal cells, and in vivo, in a mouse skin epidermal hyperplasia model. All formulations tested showed great encapsulation efficiency, nanometric size, formed monodispersed systems and a highly negative Z potential. Similar values were obtained over nine months storage at 4 degrees C, which indicates the great stability of the three types of nanoliposomes at least during the time tested. Among them, 0.1% mometasone furoate glyceroethohyalurosomes were the best formulation to protect cells against oxidative stress and their anti-inflammatory efficacy was confirmed in vivo, being even more effective than the marketed form (Elocom (R)), as the reduction in the inflammation was even similar to 15% higher than that achieved with the commercial cream. Selected formulations could be potential candidates as new vehiculation systems for mometasone furoate. The presence of hyaluronic acid in glyceroethohyalurosomes makes them the best candidates in preventing/treating skin inflammatory lesions
Active bilayer films of thermoplastic starch and polycaprolactone obtained by compression molding
Chapter 7 of the DOCTORAL THESIS "Development and characterization of corn starch films by blending with more hydrophobic compounds" by Rodrigo Ortega Toro https://riunet.upv.es/handle/10251/52521[EN] Bilayer films consisting of one layer of PCL with either one of thermoplastic starch (S) or one of thermo-plastic starch with 5% PCL (S95) were obtained by compression molding. Before compression, aqueoussolutions of ascorbic acid or potassium sorbate were sprayed onto the S or S95 layers in order to plas-ticize them and favor layer adhesion. S95 films formed bilayers with PCL with very good adhesion andgood mechanical performance, especially when potassium sorbate was added at the interface. All bilayersenhanced their barrier properties to water vapour (up to 96% compared to net starch films) and oxygen(up to 99% compared to PCL pure). Bilayers consisting of PCL and starch containing 5% PCL, with potas-sium sorbate at the interface, showed the best mechanical and barrier properties and interfacial adhesionwhile having active properties, associated with the antimicrobial action of potassium sorbate.The authors acknowledge the financial support from the Spanish Ministerio de Educacion y Ciencia throughout the project AGL2013-42989-R. Rodrigo Ortega-Toro thanks the Conselleria de Educacio de la Comunitat Valenciana for the Santiago Grisolia grant (GROSO-LIA 2012/001). Authors also thank to Electron Microscopy Service of the UPV for their technical assistance.Ortega-Toro, R.; Morey, I.; Talens Oliag, P.; Chiralt, A. (2015). Active bilayer films of thermoplastic starch and polycaprolactone obtained by compression molding. Carbohydrate Polymers. 127:282-290. https://doi.org/10.1016/j.carbpol.2015.03.080S28229012
Influence of citric acid on the properties and stability of starch-polycaprolactone based films
[EN] The influence of citric acid (CA) on structural and physicochemical properties of blend films based on corn starch and polycaprolactone (PCL) was studied. Films were obtained by melt blending of starch and PCL and compression molding. Phase separation of polymers observed by scanning electron microscope and atomic force microscope was reduced by CA incorporation. CA affected both starch and PCL crystallization as deduced from the X-ray diffraction patterns and values of melting enthalpy. Glass transition of starch was reduced by PCL incorporation, while this occurred to a greater extent in films containing CA. Obtained results point to enhanced interactions between PCL and starch chains in films with CA, although this only quantitatively benefits the film properties at a low PCL ratio. Compounding starch with small amounts of PCL, using glycerol and CA, can supply films with better functional properties than net starch films.The authors acknowledge the financial support from the Spanish Ministerio de Educacion y Ciencia throughout the projects AGL2010-20694 and AGL2013-42989-R. Rodrigo Ortega-Toro thanks the Conselleria de Educacio de la Comunitat Valenciana for the Santiago Grisolia grant. Authors also thank the Electron Microscopy Service of the UPV for their technical assistance.Ortega Toro, R.; Collazo-Bigliardi, S.; Talens Oliag, P.; Chiralt, A. (2015). Influence of citric acid on the properties and stability of starch-polycaprolactone based films. Journal of Applied Polymer Science. 133(2):1-16. doi:10.1002/app.42220S1161332Flieger, M., Kantorová, M., Prell, A., Řezanka, T., & Votruba, J. (2003). Biodegradable plastics from renewable sources. Folia Microbiologica, 48(1), 27-44. doi:10.1007/bf02931273GARCIA, M., PINOTTI, A., MARTINO, M., & ZARITZKY, N. (2004). 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Data calibration for the MASCARA and bRing instruments
Aims: MASCARA and bRing are photometric surveys designed to detect
variability caused by exoplanets in stars with . Such variability
signals are typically small and require an accurate calibration algorithm,
tailored to the survey, in order to be detected. This paper presents the
methods developed to calibrate the raw photometry of the MASCARA and bRing
stations and characterizes the performance of the methods and instruments.
Methods: For the primary calibration a modified version of the coarse
decorrelation algorithm is used, which corrects for the extinction due to the
earth's atmosphere, the camera transmission, and intrapixel variations.
Residual trends are removed from the light curves of individual stars using
empirical secondary calibration methods. In order to optimize these methods, as
well as characterize the performance of the instruments, transit signals were
injected in the data. Results: After optimal calibration an RMS scatter of 10
mmag at is achieved in the light curves. By injecting transit
signals with periods between one and five days in the MASCARA data obtained by
the La Palma station over the course of one year, we demonstrate that MASCARA
La Palma is able to recover 84.0, 60.5 and 20.7% of signals with depths of 2, 1
and 0.5% respectively, with a strong dependency on the observed declination,
recovering 65.4% of all transit signals at versus 35.8% at
. Using the full three years of data obtained by MASCARA La
Palma to date, similar recovery rates are extended to periods up to ten days.
We derive a preliminary occurrence rate for hot Jupiters around A-stars of , knowing that many hot Jupiters are still overlooked. In the era of
TESS, MASCARA and bRing will provide an interesting synergy for finding
long-period ( days) transiting gas-giant planets around the brightest
stars.Comment: 18 pages, 17 figures, accepted for publication in A&
"It has no meaning to me". How do researchers understand the effectiveness of literature searches? A qualitative analysis and preliminary typology of understandings
This study aimed to address the question: what does “effectiveness” mean to researchers in the context of literature searching for systematic reviews?
We conducted a thematic analysis of responses to an e‐mail survey. Eighty‐nine study authors, whose studies met inclusion in a recent review (2018), were contacted via e‐mail and asked three questions; one directly asking the question: in literature searching, what does effective (or effectiveness in) literature searching mean to you?
Thirty‐eight (46%) responses were received from diverse professional groups, including: literature searchers, systematic reviewers, clinicians and researchers. A shared understanding of what effectiveness means was not identified. Instead, five themes were developed from data: 1) effectiveness is described as a metric; 2) effectiveness is a balance between metrics; 3) effectiveness can be categorised by search purpose; 4) effectiveness is an outcome; and, 5) effectiveness is an experimental concept. We propose that these themes constitute a preliminary typology of understandings.
No single definition of effectiveness was identified. The proposed typology suggests that different researchers have differing understandings of effectiveness. This could lead to uncertainty as to the aim and the purpose of literature searches and confusion about the outcomes. The typology offers a potential route for further exploration
Application of edible coatings to partially dehydrated pineapple for use in fruit cereal products
[EN] The present work analyzes the application method and the effectiveness of edible coatings based on caseinates or chitosan in partially dehydrated pineapple for its use in dry fruit-cereal products. Commercial breakfast cereals and partially dehydrated pineapples prepared by osmotic dehydration and vacuum impregnation were used for the experiments. Four coating application techniques, working at atmospheric pressure or applying vacuum impregnation, were used for coating the pineapple samples. Coated and uncoated samples were stored, at 20 degrees C with breakfast cereals and were subsequently analyzed weekly during 6 months. Critical water activity and critical water content for the glass transition of the cereals at 20 degrees C were estimated as 0.60 and 9.1 g water/100 g of product, respectively. Results show that the application of coatings by vacuum impregnation and sample air drying after coating, considerably extends the shelf-life of the pineapple-cereal system when caseinate based coatings are used. Chitosan based coatings are less effective to limit water vapor transfer and the critical moisture content of cereals are reached during the storage period. (c) 2012 Elsevier Ltd. All rights reserved.The authors acknowledge the financial support from the Conselleria de Educacion de la Comunidad Valenciana through Project GVPRE/2008/355 and Universitat Politecnica de Valencia through Project PAID-06-08-3242 M.J. Fabra thanks the support of Campus de Excelencia Internacional from Universitat Politecnica de Valencia.Talens Oliag, P.; Pérez-Masià, R.; Fabra Rovira, MJ.; Vargas, M.; Chiralt, A. (2012). Application of edible coatings to partially dehydrated pineapple for use in fruit cereal products. Journal of Food Engineering. 112:86-93. https://doi.org/10.1016/j.jfoodeng.2012.03.022S869311
El yacimiento arqueológico de El Saucedo (Talavera La Nueva, Toledo): balance y perspectivas
En este artículo presentamos una síntesis de los trabajos de investigación, conservación y difusión reali-zados en el yacimiento de b'l Saucedo hasta el presente, así como un esbozo de los planes de actuación para el futuro
bRing: An observatory dedicated to monitoring the Pictoris b Hill sphere transit
Aims. We describe the design and first light observations from the
Pictoris b Ring ("bRing") project. The primary goal is to detect photometric
variability from the young star Pictoris due to circumplanetary
material surrounding the directly imaged young extrasolar gas giant planet
\bpb. Methods. Over a nine month period centred on September 2017, the Hill
sphere of the planet will cross in front of the star, providing a unique
opportunity to directly probe the circumplanetary environment of a directly
imaged planet through photometric and spectroscopic variations. We have built
and installed the first of two bRing monitoring stations (one in South Africa
and the other in Australia) that will measure the flux of Pictoris,
with a photometric precision of over 5 minutes. Each station uses two
wide field cameras to cover the declination of the star at all elevations.
Detection of photometric fluctuations will trigger spectroscopic observations
with large aperture telescopes in order to determine the gas and dust
composition in a system at the end of the planet-forming era. Results. The
first three months of operation demonstrate that bRing can obtain better than
0.5\% photometry on Pictoris in five minutes and is sensitive to
nightly trends enabling the detection of any transiting material within the
Hill sphere of the exoplanet
MASCARA-2 b: A hot Jupiter transiting the A-star HD185603
In this paper we present MASCARA-2 b, a hot Jupiter transiting the
A2 star HD 185603. Since early 2015, MASCARA has taken more than 1.6 million
flux measurements of the star, corresponding to a total of almost 3000 hours of
observations, revealing a periodic dimming in the flux with a depth of .
Photometric follow-up observations were performed with the NITES and IAC80
telescopes and spectroscopic measurements were obtained with the Hertzsprung
SONG telescope. We find MASCARA-2 b orbits HD 185603 with a period of
at a distance of , has a radius of and place a
upper limit on the mass of . HD 185603 is a
rapidly rotating early-type star with an effective temperature of
and a mass and radius of
, , respectively. Contrary
to most other hot Jupiters transiting early-type stars, the projected planet
orbital axis and stellar spin axis are found to be aligned with . The brightness of the host star and the high equilibrium
temperature, , of MASCARA-2 b make it a suitable target for
atmospheric studies from the ground and space. Of particular interest is the
detection of TiO, which has recently been detected in the similarly hot planets
WASP-33 b and WASP-19 b.Comment: 8 pages, 4 figures, Accepted for publication in A&
Control of skin damages caused by oxidative stress using mangiferin and naringin co-loaded in phospholipid vesicles
Mangiferin and naringin, two naturally occurring antioxidant molecules, were co-loaded in phospholipid vesicles designed for skin delivery. Ultradeformable-liposomes containing tween 80 as edge activator, were used as basic formulation, which was modified adding glycerol (glycerosomes) or a mixture of glycerol and ethanol (etglycerosomes) and further enriched with a polymer, sodium hyaluronate (glycerohyalurosomes and etglycerohyalurosomes), to evaluate the role of vesicle composition on their features and performances. Mean dimeter, polydispersity index and zeta potential of prepared vesicles were measured along with their stabilitcay on storage for 90 days, rheological behavior and suitability as systems for the delivery of these active molecules into and through the skin. Vesicles enriched with sodium hyaluronate were the most stable and the smallest and favored the deposition of both mangiferin and naringin in the whole skin, in a better extent than those without polymer. All the vesicles were highly biocompatible and capable of protecting fibroblasts against hydrogen peroxide-induced oxidative damages in vitro. Once more, glycerohyalurosomes and et-glycerohyalurosomes where those which improved the most the beneficial effect of mangiferin and naringin, as they were capable of effectively counteracting the formation of skin lesion, or even promoting the wound healing, thanks to their greater ability to inhibit both myeloperoxydase activity and oedema formation in vivo in a model mouse in which wound was induced using phorbol acetate
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