Liver phospholipids fatty acids composition in response to different types of diets in rats of both sexes

Background: Dietary intake influence changes in fatty acids (FA) profiles in liver which plays a central role in fatty acid metabolism, triacylglycerol synthesis and energy homeostasis. We investigated the effects of 4-weeks treatment with milk-and fish-based diet, on plasma biochemical parameters and FA composition of liver phospholipids (PL) in rats of both sexes. Methods: Adult, 4 months old, Wistar rats of both sexes, were fed with different types of diets: standard, milk-based and fish-based, during 4 weeks. Analytical characterization of different foods was done. Biochemical parameters in plasma were determined. Fatty acid composition was analyzed by gas-chromatography. Statistical significance of FA levels was tested with two-way analysis of variance (ANOVA) using the sex of animals and treatment (type of diet) as factors on logarithmic or trigonometric transformed data. Results: Our results showed that both, milk-and fish-based diet, changed the composition and ratio of rat liver phospholipids FA, in gender-specific manner. Initially present sex differences appear to be dietary modulated. Although, applied diets changed the ratio of total saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA), and effects were gender specific. Milk-based diet lowered SFA and elevated MUFA in males and increased PUFA in females vs. standard diet. The same diet decreased n-3, increased n-6 and n-6/n-3 ratio in males. Fish-based diet increased n-3, decreased n-6 and n-6/n-3 ratio vs. standard and milk-based diet in females. However, the ratio of individual FA in liver PL was also dietary-influenced, but with gender specific manner. While in females fish-based diet decreased AA (arachidonic acid) increased level of EPA (eicosapentaenoic acid), DPA (docosapentaenoic acid) and DHA (docosahexaenoic acid), the same diet elevated only DHA levels in males. Conclusion: Gender related variations in FA composition of rat liver PL were observed, and results have shown that those initial differences could be significantly modulated by the type of diet. Furthermore, the modulatory effects of milk-and fish-based diets on liver phospholipids FA profiles appeared to be sex-specific

Effect of correlation and dielectric confinement on 1S1/2(e)nS3/2(h)Excitons in CdTe/CdSe and CdSe/CdTe Type-II quantum dots

Controlled reduction of graphene oxide is an alternative and promising method to tune the electronic and optically active energy gap of this two-dimensional material in the energy range of the visible light spectrum. By means of ab initio calculations, based on hybrid density functional theory, that combine the Hartree–Fock method with the generalized gradient approximation (GGA), we investigated the electronic, optical, and radiative recombination properties of partially reduced graphene oxide, modelled as small islands of pristine graphene formed in an infinite sheet of graphene oxide. We predict that tuning of optically active gaps, in the wide range from ∼6.5 eV to ∼0.25 eV, followed by the electron radiative transition times in the range from ns to μs, can be effected by controlling the level of oxidization

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

The effect of ceria and zirconia nanoparticles on the corrosion behaviour of cataphoretic epoxy coatings on AA6060 alloy

In this work an attempt was made to produce epoxy coating doped with ceria (CeO2) and/or zirconia (ZrO2) nanoparticles, in single step electrophoretric deposition process. Deposition was carried out on AA6060 cataforetically from epoxy resin suspension containing synthesized stable aqueous colloidal dispersions (sols) of CeO2 and ZrO2. The influence of ceria and zirconia nanoparticles on the physicochemical characteristics of epoxy coatings was evaluated by energy dispersive X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis and adhesion measurements, while their corrosion stability during immersion in 0.5 M NaCl solution was monitored by electrochemical impedance spectroscopy. All ceria and/or zirconia containing coatings showed better corrosion stability and adhesion than pure epoxy coating, while between doped epoxy coatings one with CeO2/ZrO2 exhhibited the greatest values of charge-transfer resistance due to synergetic effect of both types of added nanoparticles

Hydrostatic pressure experiments on dilute nitride alloys

GaN(x)As(1-x) and Ga(1-y)In(y)N(x)As(1-x) are the most prominent members of a novel class of non-amalgamation type semiconductor alloys where a fraction x of the anions of the host (e.g., GaAs or Ga(1-y)In(y)As) is replaced by N isovalent impurity atoms. The localized N-states in GaN(x)As(1-x) and Ga(1-y)In(y)As(1-x) form a series of discrete energy levels (e.g., isolated N-state, N-pairs and higher order N-cluster states) resonant with the conduction band of the host. The effect of the alloying with nitrogen on the bandstructure of GaN(x)As(1-x) and Ga(1-y)In(y)N(x)As(1-x) can be well parameterized using a band-anticrossing (BAC) model, namely, assuming a level repulsion between an effective N-state and the conduction band-edge state. The dependence of several physical properties on nitrogen incorporation can be predicted qualitatively in the framework of this model, e.g., a tremendous increase of the electron effective mass in GaN(x)As(x) with increasing x, a huge cross section for scattering of electrons by N impurities in electronic transport, etc. Most of these predictions can be tested and verified by performing hydrostatic pressure experiments which, within the picture of the BAC model, allow one to tune continuously the energy difference between the host-like conduction band edge and the effective N-level within one and the same specimen. Several examples of this kind will be discussed. Furthermore, we will demonstrate the limitations of the BAC model in the case of GaN(x)P(1-x) and also of GaN(x)As(1-x). In particular, we will show several examples where the description by a single effective N-state fails and that the multiplicity of the N-states needs to be taken into account. Again hydrostatic pressure experiments prove to be a useful and suitable tool for revealing the effects due to N-cluster states. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim