Myristic acid potentiates palmitic acid-induced lipotoxicity and steatohepatitis associated with lipodystrophy by sustaning de novo ceramide synthesis.

Palmitic acid (PA) induces hepatocyte apoptosis and fuels de novo ceramide synthesis in the endoplasmic reticulum (ER). Myristic acid (MA), a free fatty acid highly abundant in copra/palmist oils, is a predictor of nonalcoholic steatohepatitis (NASH) and stimulates ceramide synthesis. Here we investigated the synergism between MA and PA in ceramide synthesis, ER stress, lipotoxicity and NASH. Unlike PA, MA is not lipotoxic but potentiated PA-mediated lipoapoptosis, ER stress, caspase-3 activation and cytochrome c release in primary mouse hepatocytes (PMH). Moreover, MA kinetically sustained PA-induced total ceramide content by stimulating dehydroceramide desaturase and switched the ceramide profile from decreased to increased ceramide 14:0/ceramide16:0, without changing medium and long-chain ceramide species. PMH were more sensitive to equimolar ceramide14:0/ceramide16:0 exposure, which mimics the outcome of PA plus MA treatment on ceramide homeostasis, than to either ceramide alone. Treatment with myriocin to inhibit ceramide synthesis and tauroursodeoxycholic acid to prevent ER stress ameliorated PA plus MA induced apoptosis, similar to the protection afforded by the antioxidant BHA, the pan-caspase inhibitor z-VAD-Fmk and JNK inhibition. Moreover, ruthenium red protected PMH against PA and MA-induced cell death. Recapitulating in vitro findings, mice fed a diet enriched in PA plus MA exhibited lipodystrophy, hepatosplenomegaly, increased liver ceramide content and cholesterol levels, ER stress, liver damage, inflammation and fibrosis compared to mice fed diets enriched in PA or MA alone. The deleterious effects of PA plus MA-enriched diet were largely prevented by in vivo myriocin treatment. These findings indicate a causal link between ceramide synthesis and ER stress in lipotoxicity, and imply that the consumption of diets enriched in MA and PA can cause NASH associated with lipodystrophy

Prospection and identification of traditional-heritage Peruvian grapevine cultivars (Vitis vinifera L.) from Ica and Cañete valleys

Interest in ancient and autochthonous cultivars has increased in recent years since they are directly related to the historical and cultural values of a region. Ica and Cañete valleys (Peru) have a long history of grapevine cultivation and the aim of this study was to identify phenotypes corresponding to the most used varieties for the local production of Pisco and wine. The 29 samples were collected in 17 vineyards in the Ica and Cañete valleys, and were analyzed using 20 molecular markers and 5 morphological descriptors according to the OIV. Results showed that the 29 collected samples corresponded to 11 genotypes: seven traditional cultivars and four unknown genotypes not registered previously. The known cultivars were 'Muscat of Alexandria', 'Listán Prieto', 'Quebranta', 'Moscatel Rosado', 'Pedro Giménez', 'Muscat Hamburg' and 'Palomino Fino'. The four not registered genotypes are locally known as 'Mollar de Ica', 'Moscatel Rosada de Cañete', 'Prieta Mollar' and 'Torontel'. All of them correspond to offspring of traditional-heritage Peruvian cultivars. We also found a phenotypic variation of 'Listán Prieto' with muscat flavor and identified phenotypic berry color variations in 'Quebranta'. This study increases the knowledge of traditional Peruvian grape varieties and highlight the genetic variability preserved in the traditional vineyards of local producers

Boson Stars in General Scalar-Tensor Gravitation: Equilibrium Configurations

We study equilibrium configurations of boson stars in the framework of general scalar-tensor theories of gravitation. We analyse several possible couplings, with acceptable weak field limit and, when known, nucleosynthesis bounds, in order to work in the cosmologically more realistic cases of this kind of theories. We found that for general scalar-tensor gravitation, the range of masses boson stars might have is comparable with the general relativistic case. We also analyse the possible formation of boson stars along different eras of cosmic evolution, allowing for the effective gravitational constant far out form the star to deviate from its current value. In these cases, we found that the boson stars masses are sensitive to this kind of variations, within a typical few percent. We also study cases in which the coupling is implicitly defined, through the dependence on the radial coordinate, allowing it to have significant variations in the radius of the structure.Comment: 19 pages in latex, 3 figures -postscript- may be sent via e-mail upon reques

Simple nonlinearity evaluation and modeling of low-noise amplifiers with application to radio astronomy receivers

This paper describes a comparative nonlinear analysis of low-noise amplifiers (LNAs) under different stimuli for use in astronomical applications. Wide-band Gaussian-noise input signals, together with the high values of gain required, make that figures of merit, such as the 1 dB compression (1 dBc) point of amplifiers, become crucial in the design process of radiometric receivers in order to guarantee the linearity in their nominal operation. The typical method to obtain the 1 dBc point is by using single-tone excitation signals to get the nonlinear amplitude to amplitude (AM-AM) characteristic but, as will be shown in the paper, in radiometers, the nature of the wide-band Gaussian-noise excitation signals makes the amplifiers present higher nonlinearity than when using single tone excitation signals. Therefore, in order to analyze the suitability of the LNA’s nominal operation, the 1 dBc point has to be obtained, but using realistic excitation signals. In this work, an analytical study of compression effects in amplifiers due to excitation signals composed of several tones is reported. Moreover, LNA nonlinear characteristics, as AM-AM, total distortion, and power to distortion ratio, have been obtained by simulation and measurement with wide-band Gaussian-noise excitation signals. This kind of signal can be considered as a limit case of a multitone signal, when the number of tones is very high. The work is illustrated by means of the extraction of realistic nonlinear characteristics, through simulation and measurement, of a 31 GHz back-end module LNA used in the radiometer of the QUIJOTE (Q U I JOint TEnerife) CMB experimen

Tectonic fabrics vs. mineralogical artifacts in AMS analysis: A case study of the Western Morocco extensional Triassic basins

New magnetic fabric data from 48 sites in Upper Triassic red beds from the Argana, Asni and Tizi n''Tichka areas in the western High Atlas, in combination with rock magnetic analyses, SEM observations and qualitative chemical analyses, reveal that mineralization processes can affect the primary (extensional) or secondary (post-depositional) magnetic fabrics. Twenty out of the 48 analyzed sites show tectonic-related fabrics consistent with the rifting stage (primary). Their orientation suggests that the extensional Atlasic (for the Asni area) and Atlantic (for Argana area) distinct directions prevailing during Liassic times are already present in the Upper Triassic sediments. The other 28 sites show axes switching (including different possibilities, kmax-kmin or kint-kmin), indicating their secondary development related to mineralogical changes after deposition. However, orientation of magnetic susceptibility axes (without considering their relative value) is consistent with the main directions obtained for the rifting stage. This magnetic fabric study also suggests that (i) extension had a small transtensional component and (ii) there is a limited influence of compressional inversion tectonics

Large-scale evaluation of shotgun triacylglycerol profiling for the fast detection of olive oil adulteration

Fast and effective analytical screening tools providing new suitable authenticity markers and applicable to a large number of samples are required to efficiently control the global olive oil (OO) production, and allow the rapid detection of low levels of adulterants even with fatty acid composition similar to OO. The present study aims to develop authentication models for the comprehensive detection of illegal blends of OO with adulterants including different types of high linoleic (HL) and high oleic (HO) vegetable oils at low concentrations (2–10%) based on shotgun triacylglycerol (TAG) profile obtained by Flow Injection Analysis-Heated Electrospray Ionisation-High Resolution Mass Spectrometry (FIA-HESI-HRMS) at a large-scale experimental design. The sample set covers a large natural variability of both OO and adulterants, resulting in more than one thousand samples analysed. A combined PLS-DA binary modelling based on shotgun TAG profiling proved to be a fit for purpose screening tool in terms of efficiency and applicability. The external validation resulted in the correct classification of the 86.8% of the adulterated samples (diagnostic sensitivity = 0.87), and the 81.1% of the genuine samples (diagnostic specificity = 0.81), with an 85.1% overall correct classification (efficiency = 0.85)

Selective Fractionation And Isolation Of Allelopathic Compounds From Helianthus Annuus L. Leaves By Means Of High-Pressure Techniques

The allelopathic potential of Helianthus annuus L. leaves was study based on bio-directed chemical fractionation approach. Aerial parts of H. annuus were extracted by means of SFE using supercritical carbon dioxide (scCO2) and ESE using CO2+50% EtOH/H2O (varying ethanol in water from 0 to 100%). Extractions were carried out at 400 bar, 55 °C, 20 g/min and for 4 h. Then, extracts were fractionated in three separators at the following conditions: S1: 200 bar/45 °C; S2: 90 bar/40 °C; and S3: 1 atm/30 °C. ESE obtained higher overall yields than scCO2 and the use of water as cosolvent (CO2+50% H2O) resulted in a S3 fraction free from chlorophylls and rich in bioactive compounds. 14 compounds, including fatty acids, terpenes, flavonoids and heliannuols, were isolated from this fraction. After performing the bioassay on pure compounds, heliannuol D, tambulin, pinoresinol and sesquiterpene 10-oxo-isodauc-3-en-15-al showed the most effective inhibitor profiles

pySCu: A new python code for analyzing remagnetizations directions by means of small circle utilities

The Small Circle (SC) methods are founded upon two main starting hypotheses: (i) the analyzed sites were remagnetized contemporarily, acquiring the same paleomagnetic direction. (ii) The deviation of the acquired paleomagnetic signal from its original direction is only due to tilting around the bedding strike and therefore the remagnetization direction must be located on a small circle (SC) whose axis is the strike of bedding and contains the in situ paleomagnetic direction. Therefore, if we analyze several sites (with different bedding strikes) their SCs will intersect in the remagnetization direction. The SC methods have two applications: (1) the Small Circle Intersection (SCI) method is capable of providing adequate approximations to the expected paleomagnetic direction when dealing with synfolding remagnetizations. By comparing the SCI direction with that predicted from an apparent polar wander path, the (re)magnetization can be dated. (2) Once the remagnetization direction is known, the attitude of the beds (at each site) can be restored to the moment of the acquisition of the remagnetization, showing a palinspastic reconstructuion of the structure. Some caveats are necessary under more complex tectonic scenarios, in which SC-based methods can lead to erroneous interpretations. However, the graphical output of the methods tries to avoid ‘black-box’ effects and can minimize misleading interpretations or even help, for example, to identify local or regional vertical axis rotations. In any case, the methods must be used with caution and always considering the knowledge of the tectonic frame. In this paper, some utilities for SCs analysis are automatized by means of a new Python code and a new technique for defining the uncertainty of the solution is proposed. With pySCu the SCs methods can be easily and quickly applied, obtaining firstly a set of text files containing all calculated information and subsequently generating a graphical output on the fly.CGL2012-38481 and CGL2016-77560 of the MINECO (Spanish Ministry of Economy and Competitiveness) with also FEDER founding (European Union). PC acknowledges the MINECO for the F.P.I. research grant BES-2013-062988. LT acknowledges support from National Science Foundation grant # EAR 1345003

The Behaviour Of Cosmological Models With Varying-G

We provide a detailed analysis of Friedmann-Robertson-Walker universes in a wide range of scalar-tensor theories of gravity. We apply solution-generating methods to three parametrised classes of scalar-tensor theory which lead naturally to general relativity in the weak-field limit. We restrict the parameters which specify these theories by the requirements imposed by the weak-field tests of gravitation theories in the solar system and by the requirement that viable cosmological solutions be obtained. We construct a range of exact solutions for open, closed, and flat isotropic universes containing matter with equation of state $p\leq \frac{1}{3}\rho$ and in vacuum. We study the range of early and late-time behaviours displayed, examine when there is a `bounce' at early times, and expansion maxima in closed models.Comment: 58 pages LaTeX, 6 postscript figures, uses eps