37 research outputs found

    Faunistic Composition, Ecological Properties and Zoogeographical Composition of the Family Elateridae (Coleoptera) of the Central Anatolian Region of Turkey

    Get PDF
    The focus of this study was to understand the faunistic composition, ecological properties and zoogeographical composition of Elateridae (Coleoptera) of the Central Anatolian region. 72 species belonging to seven subfamilies and 25 genera were identified. The major part of the Elateridae fauna of the Central Anatolian region is formed by the subfamilies Elaterinae and Cardiophorinae. The genus Cardiophorus was the most species-rich genus. The species composition of the Elateridae fauna of the Central Anatolian region is partially consistent with known Elateridae fauna of Turkey. The Central Anatolian region shares most species with the European part of the Western Palaearctic as does the Elateridae fauna of Turkey. Detailed localities of nine species are given for the first time for Turkey, with emphasis on the Central Anatolian region

    Elevated Pontine and Putamenal GABA Levels in Mild-Moderate Parkinson Disease Detected by 7 Tesla Proton MRS

    Get PDF
    Background: Parkinson disease (PD) is characterized by the degeneration of nigrostriatal dopaminergic neurons. However, postmortem evidence indicates that the pathology of lower brainstem regions, such as the pons and medulla, precedes nigral involvement. Consistently, pontomedullary damage was implicated by structural and PET imaging in early PD. Neurochemical correlates of this early pathological involvement in PD are unknown. Methodology/Principal Finding: To map biochemical alterations in the brains of individuals with mild-moderate PD we quantified neurochemical profiles of the pons, putamen and substantia nigra by 7 tesla (T) proton magnetic resonance spectroscopy. Thirteen individuals with idiopathic PD (Hoehn & Yahr stage 2) and 12 age- and gender-matched healthy volunteers participated in the study. c-Aminobutyric acid (GABA) concentrations in the pons and putamen were significantly higher in patients (N = 11, off medications) than controls (N = 11, p,0.001 for pons and p,0.05 for putamen). The GABA elevation was more pronounced in the pons (64%) than in the putamen (32%). No other neurochemical differences were observed between patients and controls. Conclusion/Significance: The GABA elevation in the putamen is consistent with prior postmortem findings in patients with PD, as well as with in vivo observations in a rodent model of PD, while the GABA finding in the pons is novel. The more significant GABA elevation in the pons relative to the putamen is consistent with earlier pathological involvement of th

    EstaciĂłn Experimental de Aula Dei. Memoria anual 2014

    Get PDF
    67 Pags.Esta memoria recoge la actividad científica de la Estación Experimental de Aula Dei (EEAD-CSIC) durante el año 2014, conteniendo información específica sobre las siguientes actividades de la EEAD-CSIC: Publicaciones (ISI y no ISI; Actas de congresos; Libros y Capítulos de Libro), Transferencia tecnológica, Tesis, Congresos, Cursos, Seminarios, Estancias, Actividades de cultura científica, Eventos. Incluye, ademås, un informe de financiación, directorio del personal en activo durante el año y tabla-resumen de las estadísticas relacionadas con los procesos técnicos y servicios de la Unidad Técnica de Biblioteca y Documentación.Peer reviewe

    Alterations in Energy/Redox Metabolism Induced by Mitochondrial and Environmental Toxins: A Specific Role for Glucose-6-Phosphate-Dehydrogenase and the Pentose Phosphate Pathway in Paraquat Toxicity

    Get PDF
    Parkinson’s disease (PD) is a multifactorial disorder with a complex etiology including genetic risk factors, environmental exposures, and aging. While energy failure and oxidative stress have largely been associated with the loss of dopaminergic cells in PD and the toxicity induced by mitochondrial/environmental toxins, very little is known regarding the alterations in energy metabolism associated with mitochondrial dysfunction and their causative role in cell death progression. In this study, we investigated the alterations in the energy/redox-metabolome in dopaminergic cells exposed to environmental/mitochondrial toxins (paraquat, rotenone, 1-methyl-4-phenylpyridinium [MPP+], and 6-hydroxydopamine [6-OHDA]) in order to identify common and/or different mechanisms of toxicity. A combined metabolomics approach using nuclear magnetic resonance (NMR) and direct-infusion electrospray ionization mass spectrometry (DI-ESI-MS) was used to identify unique metabolic profile changes in response to these neurotoxins. Paraquat exposure induced the most profound alterations in the pentose phosphate pathway (PPP) metabolome. 13C-glucose flux analysis corroborated that PPP metabolites such as glucose-6-phosphate, fructose-6-phosphate, glucono-1,5-lactone, and erythrose-4-phosphate were increased by paraquat treatment, which was paralleled by inhibition of glycolysis and the TCA cycle. Proteomic analysis also found an increase in the expression of glucose-6-phosphate dehydrogenase (G6PD), which supplies reducing equivalents by regenerating nicotinamide adenine dinucleotide phosphate (NADPH) levels. Overexpression of G6PD selectively increased paraquat toxicity, while its inhibition with 6-aminonicotinamide inhibited paraquat-induced oxidative stress and cell death. These results suggest that paraquat “hijacks” the PPP to increase NADPH reducing equivalents and stimulate paraquat redox cycling, oxidative stress, and cell death. Our study clearly demonstrates that alterations in energy metabolism, which are specific for distinct mitochondiral/environmental toxins, are not bystanders to energy failure but also contribute significant to cell death progression

    Spurious Phase Correction in Multi-Shot MRSI

    No full text
    International audienceIntroductionSpectral multi-shot (MS) MRSI sequences are used essentially to decrease the scan time and enlarge the spectral width. Here, the spectral information is encoded by acquiring several experiments while shifting the readout position relative to the echo time (TE). These techniques are highly exposed to phase errors with the phase evolution being indirectly sampled through the different echo time increments. During this sampling, phase coherency is crucial. Nowadays, MS techniques can lead up to image distortion because of the loss of phase coherency between the shots. The purpose of this work is to present theoretically and experimentally how to overcome this phase problem.Subjects/MethodsWe demonstrated that during the extra delay to shift the echo time for a 2D slice selection, the phase evolvesdepending on the chemical shift with respect to the excitation frequency. The latter is generally significantlyhigher than the chemical shift, and the phase will mostly depend on it. This phase shift can be corrected oneither the acquired signal or the reconstructed image by subtracting the additional frequency excitationapplied when shifting the slice position. These methods were applied to rapid metabolic imaging (1) of a 13Cphantom and on the particular case of B0 mapping.Results/DiscussionResults showed phase errors in MS MRSI, leading to image distortion, therefore incorrect and inefficientstudies. However, applying one of the provided correction methods cancels the phase errors, improving theimage quality.Unwanted phase shifts are susceptible to be accumulated in MS techniques during different echo timeincrements, especially when the slice position is shifted from a null resonance frequency. We were able tocorrect the phase-shifting through post-processing in the k-space dimension, by image phase correctionaccording to the Nyquist frequency rule or even during a particular experimental case. The three proposedcorrection approaches were able to discard the spurious phase and then to reconstruct parametric mapsaccurately
    corecore