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Abstract  

The aim of this study was to determine whether testosterone regulates the rate of lipid synthesis in lung. Rats were either sham-operated controls (Co) or castrated (Ca)·[3H] H2O was administered in vivo, twenty-one days after castration. The animals were sacrificed 1h later to ensure that the newly synthesized lipids in the lung had been labeled. The radioactivity incorporated in the different lipid fractions that had been separated by TLC was counted. The results are expressed in ng3H incorporated/h/mg lipids. We observed that the incorporation of3H in total lipids, phospholipids and free cholesterol increased, while trygliceride and esterified cholesterol did not change in castrated rats in relation to the control. These results suggest that the rate of lipid synthesis in the lung is regulated, directly or indirectly by androgens.

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Abstract  

Thermally stimulated recovery, TSR, like as thermally stimulated depolarisation currents, is a suitable technique that allows for the study of conformational mobility in polymeric systems. Due to its relatively low equivalent frequency and transient nature, the viscoelastic data obtained from this technique are complementary to conventional dynamic mechanical analysis (DMA). In this work TSR-like experiments, including TSR, thermally stimulated creep and thermal sampling (TS) experiments were carried out in the same commercial DMA equipment, allowing for the direct comparison of the data. Some advises for running TSR experiments are presented, such as the need of performing blank experiments and temperature calibrations. The analysis of the data to obtain the thermokinetic parameters of TS experiments is revised. In particular, from the direct fitting of the data, it is reported a tendency for a linear relationship between the pairs of values of (E a, log τ0) that best adjust any TS single experiment. It is concluded that the usual equation for describing TS experiments possesses an intrinsic compensation between these two thermokinetic parameters.

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Abstract  

3D quantitative elemental maps of a section of a strand of hair were produced using a combination of PIXE-Tomography and simultaneous On/Off Axis STIM-Tomography at the University of Surrey Ion Beam Centre. The distributions of S, K, Cl, Ca, Fe and Zn were determined using the PIXE-T reconstruction package DISRA. The results were compared with conventional bulk PIXE analysis of tomographic data as determined using Dan32. The overall concentrations determined by PIXE were compared with elemental concentrations held in the University of Surrey Hair Database. All the entries currently in the database were produced using INAA. The merits and possible contributions of tomographic PIXE analysis to analysis of hair are discussed. The conclusions drawn from the PIXE-Tomography analysis can be used to argue for more stringent procedures for hair analysis at the University of Surrey.

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Journal of Thermal Analysis and Calorimetry
Authors:
A. Kyritsis
,
A. Spanoudaki
,
C. Pandis
,
L. Hartmann
,
R. Pelster
,
N. Shinyashiki
,
J. C. Rodríguez Hernández
,
J. L. Gómez Ribelles
,
M. Monleón Pradas
, and
P. Pissis

Abstract

Hydrogels based on nanocomposites of statistical poly(hydroxyethyl acrylate-co-ethyl acrylate) and silica, prepared by simultaneous copolymerization and generation of silica nanoparticles by sol–gel process at various copolymer compositions and silica contents, characterized by a fine dispersion of filler, were investigated with respect to glass transition and polymer dynamics by dielectric techniques. These include thermally stimulated depolarization currents and dielectric relaxation spectroscopy, covering together broad ranges of frequency and temperature. In addition, equilibrium water sorption isotherms were recorded at room temperature (25 °C). Special attention was paid to the investigation of effects of silica on glass transition, polymer dynamics (secondary γ and β sw relaxations and segmental α relaxation), and electrical conductivity in the dry systems (xerogels) and in the hydrogels at various levels of relative humidity/water content. An overall reduction of molecular mobility is observed in the nanocomposite xerogels, in particular at high silica contents. Analysis of the results and comparison with previous work on similar systems enable to discuss this reduction of molecular mobility in terms of constraints to polymeric motion imposed by interfacial polymer–filler interactions and by the formation of a continuous silica network interpenetrated with the polymer network at filler contents higher than about 15 wt%.

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Journal of Behavioral Addictions
Authors:
Mikel Etxandi
,
Isabel Baenas
,
Bernat Mora-Maltas
,
Roser Granero
,
Fernando Fernández-Aranda
,
Sulay Tovar
,
Neus Solé-Morata
,
Ignacio Lucas
,
Sabela Casado
,
Mónica Gómez-Peña
,
Laura Moragas
,
Amparo del Pino-Gutiérrez
,
Javier Tapia
,
Eduardo Valenciano-Mendoza
,
Marc N. Potenza
,
Ashley N. Gearhardt
,
Carlos Diéguez
, and
Susana Jiménez-Murcia

Abstract

Background

Data implicate overlaps in neurobiological pathways involved in appetite regulation and addictive disorders. Despite different neuroendocrine measures having been associated with both gambling disorder (GD) and food addiction (FA), how appetite-regulating hormones may relate to the co-occurrence of both entities remain incompletely understood.

Aims

To compare plasma concentrations of ghrelin, leptin, adiponectin, and liver-expressed antimicrobial peptide 2 (LEAP-2) between patients with GD, with and without FA, and to explore the association between circulating hormonal concentrations and neuropsychological and clinical features in individuals with GD and FA.

Methods

The sample included 297 patients diagnosed with GD (93.6% males). None of the patients with GD had lifetime diagnosis of an eating disorder. FA was evaluated with the Yale Food Addiction Scale 2.0. All patients were assessed through a semi-structured clinical interview and a psychometric battery including neuropsychological tasks. Blood samples to measure hormonal variables and anthropometric variables were also collected.

Results

From the total sample, FA was observed in 23 participants (FA+) (7.7% of the sample, 87% males). When compared participants with and without FA, those with FA+ presented both higher body mass index (BMI) (p < 0.001) and leptin concentrations, after adjusting for BMI (p = 0.013). In patients with FA, leptin concentrations positively correlated with impulsivity, poorer cognitive flexibility, and poorer inhibitory control. Other endocrine measures did not differ between groups.

Discussion and conclusions

The present study implicates leptin in co-occurring GD and FA. Among these patients, leptin concentration has been associated with clinical and neuropsychological features, such as impulsivity and cognitive performance in certain domains.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
P. Povinec
,
M. Pham
,
J. Sanchez-Cabeza
,
G. Barci-Funel
,
R. Bojanowski
,
T. Boshkova
,
W. Burnett
,
F. Carvalho
,
B. Chapeyron
,
I. Cunha
,
H. Dahlgaard
,
N. Galabov
,
L. Fifield
,
J. Gastaud
,
J. Geering
,
I. Gomez
,
N. Green
,
T. Hamilton
,
F. Ibanez
,
M. Ibn Majah
,
M. John
,
G. Kanisch
,
T. Kenna
,
M. Kloster
,
M. Korun
,
L. Liong Wee Kwong
,
J. La Rosa
,
S. Lee
,
I. Levy-Palomo
,
M. Malatova
,
Y. Maruo
,
P. Mitchell
,
I. Murciano
,
R. Nelson
,
A. Nouredine
,
J. Oh
,
B. Oregioni
,
G. Le Petit
,
H. Pettersson
,
A. Reineking
,
P. Smedley
,
A. Suckow
,
T. van der Struijs
,
P. Voors
,
K. Yoshimizu
, and
E. Wyse

Abstract  

A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides (40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides in the environment, as well as for the development and validation of analytical methods and for training purposes. The material is available from IAEA in 100 g units.

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