Recognition and quantitation of cis-vaccenic and eicosenoic fatty acids in olive oils by 13C nuclear magnetic resonance spectroscopy

The presence of 11-cis monoenoic fatty acids was detected in olive oil samples by means of ¹³C nuclear magnetic resonance spectroscopy, and the positional isomery on the glycerol backbone was derived. The 11-cis vaccenic and eicosenoic fatty acid resonances were recognized and the amounts of the fatty acids quantified. For comparison purposes, a quantitative analysis was also made by gas chromatography.     

Autoradiographic study on [3H]-[D-Ala2]-deltorphin-I binding sites in the rat brain

Previous biochemical and pharmacological studies have shown that [D-Ala2]-deltorphin-I (DADTI) has a high affinity and selectivity for delta-opioid receptors. In this study, designed to provide morphological details, the distribution of DADTI binding sites was examined by autoradiography on coronal, sagittal and horizontal frozen sections of adult rat brain. The sections were incubated with tritiated DADTI solution and exposed for 12 weeks to a 3H-sensitive film. DADTI labelling clearly demonstrated selective and high affinity binding sites of delta-opioid type in several brain regions, including olfactory system, neostriatum, nucleus accumbens, and cortical layers I-II and V-VI.     

Homicide in Capgras'' syndrome

A case of Capgras' syndrome associated with homicidal behavior is reported. The psychodynamic implications are discussed. Capgras' syndrome could lie at the base of aggressive and homicidal acts directed towards family members during psychotic breakdown. Capgras' syndrome should always be evaluated in order to prevent violent acts, understand the psychologic characteristics of the patient and undertake the corresponding treatment.     

Application of the SBAS-DInSAR technique to fault creep: A case study of the Hayward fault, California

We present a quantitative assessment of the capability of the differential SAR interferometry (DInSAR) technique referred to as Small BAseline Subset (SBAS) approach to investigate fault creep phenomena. In particular we have computed, via the SBAS-DInSAR algorithm, time series of the surface displacements relevant to the Hayward fault zone, within the San Francisco Bay Area (California), from the European Space Agency's ERS-1/2 satellite radar data for the 1992 to 2000 time period. Starting from the DInSAR time series we measured the relative displacements across the fault with no need for any atmospheric filtering step. These results have been systematically compared to the measurements available from the alignment arrays that are located along the fault. Our analysis shows that the standard deviation of the differences between the DInSAR and the in situ measurements is on the order of 2 mm. Moreover, the estimated mean deformation rates have an accuracy that is better than 1 mm/year.     

Building a virtual archive using brain architecture and Web 3D to deliver neuropsychopharmacology content over the Internet

The vast amount of heterogeneous data generated in various fields of neurosciences such as neuropsychopharmacology can hardly be classified using traditional databases. We present here the concept of a virtual archive, spatially referenced over a simplified 3D brain map and accessible over the Internet. A simple prototype (available at http://aquatics.crs4.it/neuropsydat3d) has been realized using current Web-based virtual reality standards and technologies. It illustrates how primary literature or summary information can easily be retrieved through hyperlinks mapped onto a 3D schema while navigating through neuroanatomy. Furthermore, 3D navigation and visualization techniques are used to enhance the representation of brain's neurotransmitters, pathways and the involvement of specific brain areas in any particular physiological or behavioral functions. The system proposed shows how the use of a schematic spatial organization of data, widely exploited in other fields (e.g. Geographical Information Systems) can be extremely useful to develop efficient tools for research and teaching in neurosciences.     

Conjugated linoleic acid and oxidative stress

At the present time, conjugated linoleic acid (CLA) is the subject of a growing number of studies since it has been demonstrated to possess anticarcinogenic and antiatherogenic activities in experimental animal models and to increase in some pathological states in humans. In both situations, CLA has been claimed to be involved in oxidative stress, as an antioxidant in the first case and as a primary product of a free-radical attack on polyunsaturated fatty acids (PUFA) in the other. The controversial results are due mostly to a lack of a suitable methodology because the presence of conjugated dienes (CD) in lipid moiety has been taken for years as evidence of lipid peroxidation due to the occurrence of this structure in fatty acid hydroperoxides. We have recently developed a new methodology that consists of the extraction of fatty acids, including CD fatty acid hydroperoxides, by mild saponification and their separation and identification by high-performance liquid chromatography with diode array detector. Fatty acid analyses of liver homogenate, oxidized in vitro either with Fe-ADP or t-butyl hydroperoxide (t-ButylHP), of lamb and rats fed CLA at levels known to prevent carcinogenesis, showed that CLA and its metabolites steadily decreased during oxidative stress and that they are more prone to oxidation than their corresponding methylene-interrupted fatty acids. No significant antioxidant effect of CLA was detected in any model tested. However, CD fatty acid hydroperoxides increased in the t-ButylHP model but not in the Fe-ADP model, owing probably to the degradation of CD fatty acid hydroperoxides induced by this oxidative agent. In conclusion, CLA and its metabolites seem to behave, under oxidative stress, as regular PUFA. Thus, it is highly unlikely that the peculiar effects of CLA are directly related to interference in lipoperoxidative processes.     

Modeling Parkinson’s Disease Neuropathology and Symptoms by Intranigral Inoculation of Preformed Human α-Synuclein Oligomers

The accumulation of aggregated α-synuclein (αSyn) is a hallmark of Parkinson’s disease (PD). Current evidence indicates that small soluble αSyn oligomers (αSynOs) are the most toxic species among the forms of αSyn aggregates, and that size and topological structural properties are crucial factors for αSynOs-mediated toxicity, involving the interaction with either neurons or glial cells. We previously characterized a human αSynO (H-αSynO) with specific structural properties promoting toxicity against neuronal membranes. Here, we tested the neurotoxic potential of these H-αSynOs in vivo, in relation to the neuropathological and symptomatic features of PD. The H-αSynOs were unilaterally infused into the rat substantia nigra pars compacta (SNpc). Phosphorylated αSyn (p129-αSyn), reactive microglia, and cytokine levels were measured at progressive time points. Additionally, a phagocytosis assay in vitro was performed after microglia pre-exposure to αsynOs. Dopaminergic loss, motor, and cognitive performances were assessed. H-αSynOs triggered p129-αSyn deposition in SNpc neurons and microglia and spread to the striatum. Early and persistent neuroinflammatory responses were induced in the SNpc. In vitro, H-αSynOs inhibited the phagocytic function of microglia. H-αsynOs-infused rats displayed early mitochondrial loss and abnormalities in SNpc neurons, followed by a gradual nigrostriatal dopaminergic loss, associated with motor and cognitive impairment. The intracerebral inoculation of structurally characterized H-αSynOs provides a model of progressive PD neuropathology in rats, which will be helpful for testing neuroprotective therapies.     

Effect of glass fibres and fire retardant on the combustion behaviour of composites,glass fibres–poly(butylene terephthalate)

The oxygen index (OI) of poly(butylene terephthalate) (PBT) tends to decrease when it is combined with milled-glass fibres either with or without the sizing treatment. This shows that the previously found apparent increase of flammability of PBT glass fibre composites (GFPBT) as compared to PBT is not due to the introduction of the flammable sizing together with the glass fibres in the polymer which was one suggested explanation in the literature, but rather to the wick and anti-dripping effects of glass fibres. The effectiveness of a typical brominated organic compound-antimony trioxide fire retardant system (FR), as measured by OI, is found to be larger in GFPBT as compared to PBT. A linear increase of the temperature index (TI) of PBT and of GFPBT is observed with increasing concentration of the FR. The fire retardant increases the time to ignite while it decreases the maximum rate of heat release and increases the smoke optical density and CO evolution on burning in the cone calorimeter. The dependence of fire risk and hazard assessement on the combustion model of the combustion test method is discussed for OI and cone calorimeter in the case of PBT, GFPBT and FR corresponding materials. © 1998 John Wiley & Sons, Ltd.     

Pentacene-based nanorods on Au(111) single crystals: Charge transfer, diffusion, and step-edge barriers

We investigate nanorod assemblies of two δ ₄-substituted pentacenes, namely (2,3-X ₂-9,10-Y ₂)-substituted pentacenes with X = Y = OCH₃ (MOP) and with X = F, Y = OCH₃ (MOPF), grown on Au(111) single crystals. By using a multi-technique approach based on ultraviolet photoelectron spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption, we find evidence for charge transfer screening at the interface with gold. Furthermore, the MOP and MOPF nanorods show a rough surface morphology, which was investigated with atomic force microscopy. We use molecular simulation techniques to investigate the energetic barriers to diffusion and to traverse step-edges to estimate their influence on the nanorod roughness. We find that barriers to surface diffusion on a terrace are anisotropic and that their direction favors the formation of nanorods in these materials.