636 research outputs found

    DJ-1 as a deglycating enzyme: A unique function to explain a multifaceted protein?

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    The recently reported deglycating activity of DJ-1 reconciles several features previously described for the protein. The deglycating activity reported for DJ-1 may explain its different subcellular localizations, indeed the protein has been found in the cytoplasm, nucleus, and mitochondria. Moreover, this proposed activity could help to understand the involvement of the protein in Parkinson's disease (PD), tumor growth and diabetes

    Automatic and frequency-programmable systems for feeding TMR: state of the art and available technologies

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    La tecnica di razionamento TMR (Total Mixed Ration) per bovine da latte si \ue8 molto diffusa grazie ai vantaggi offerti. La meccanizzazione si basa su carri miscelatori azionati da operatore. Alcuni limiti sono associabili alla bassa frequenza di distribuzione (1-2 volte/giorno). La recente diffusione di sistemi automatici per la preparazioone e distribuzione di TMR consente di introdurre inedite possibilit\ue0 di gestione dell'alimentazione. Circa 15 costruttori operanti su diversi concetti progettuali sono stati individuati. Tra le principali innovazioni vi \ue8 la possibilit\ue0 di variare la frequenza di distribuzione, modulare la razione, controllare gli orari di distribuzione, stimolare l'attivit\ue0 delle bovine, gestire l'ingestione di sostanza secca. Il lavoro presenta una panoramica sullo stato dell'arte della tecnologia e propone una classificazione dei robot per TMR

    Anti-oxidants in Parkinson's disease therapy: a critical point of view

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    Parkinson's disease (PD) is a degenerative neurological syndrome, which is characterized by the preferential death of dopaminergic (DAergic) neurons in the SubstantiaNigra. The pathogenesis of this disorder remains poorly understood and PD is still incurable. Currentdrug treatmentsare aimedprimarily for the treatmentof symptoms to improve the quality of life. Therefore, there is a need to find out new therapeutic strategies that not only provide symptomatic relief but also halt or reverse the neuronal damage hampering PD progression. Oxidative stress has been identified as one of the major contributors for the nigral loss in both sporadic and genetic forms of PD. In this review we first evaluate the current literature that link oxidative stress and mitochondrial dysfunction to PD. We then consider the results obtained through the treatmentof animal modelsor PD patients withmolecules that prevent oxidative stress or reduce mitochondrial dysfunction

    Circadian Rhythm Abnormalities in Parkinson's Disease from Humans to Flies and Back

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    Clinical and research studies have suggested a link between Parkinson\u2019s disease (PD) and alterations in the circadian clock. Drosophila melanogaster may represent a useful model to study the relationship between the circadian clock and PD. Apart from the conservation of many genes, cellular mechanisms, signaling pathways, and neuronal processes, Drosophila shows an organized central nervous system and well-characterized complex behavioral phenotypes. In fact, Drosophila has been successfully used in the dissection of the circadian system and as a model for neurodegenerative disorders, including PD. Here, we describe the fly circadian and dopaminergic systems and report recent studies which indicate the presence of circadian abnormalities in some fly PD genetic models. We discuss the use of Drosophila to investigate whether, in adults, the disruption of the circadian system might be causative of brain neurodegeneration. We also consider approaches using Drosophila, which might provide new information on the link between PD and the circadian clock. As a corollary, since PD develops its symptomatology over a large part of the organism\u2019s lifespan and given the relatively short lifespan of fruit flies, we suggest that genetic models of PD could be used to perform lifelong screens for drug-modulators of general and/or circadian-related PD traits

    Procedure and layout for the development of a fatigue test on an agricultural implement by a four poster test bench

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    The increasing demand in agricultural vehicles’ power requirements, payloads and driving speeds increases issues related to tractors and farm implements exposure to solicitations. One of the main factors to be taken into account for fatigue test developing on agricultural machines is the heterogeneity of the environment and activity in which the tractor operates. In particular, for contractors the use in transport conditions both on terrain and road becomes important. As far as transport is concerned. factors mainly affecting solicitations on carried implement are soil profile roughness, tractor settings and forward speed. In this paper, CRA-ING laboratory of Treviglio, Italy, together with Frandent Group s.r.l. (Osasco, Italy), analyse the possibility of creating a solicitation profile by means of one four poster test bench for fatigue test on a carried implement simulating transport conditions. Accelerations at the hubs of the tractor were acquired during transport on terrain and reproduced with one electro-hydraulic four posters test bench on one dummy of a tractor developed for carrying the implement. Artificial bumps were mathematically created and introduced in the time history to simulate squares solicitations. Twelve hours of test were carried out. This experience confirmed the possibility of carrying out laboratory fatigue test on agricultural implements by reproducing specific field conditions solicitations with four poster test bench

    A new time-varying model for forecasting long-memory series

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    In this work we propose a new class of long-memory models with time-varying fractional parameter. In particular, the dynamics of the long-memory coefficient, dd, is specified through a stochastic recurrence equation driven by the score of the predictive likelihood, as suggested by Creal et al. (2013) and Harvey (2013). We demonstrate the validity of the proposed model by a Monte Carlo experiment and an application to two real time series

    Copper Ions and Parkinson's Disease: Why Is Homeostasis So Relevant?

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    The involvement of copper in numerous physiological processes makes this metal ion essential for human life. Alterations in copper homeostasis might have deleterious consequences, and several neurodegenerative disorders, including Parkinson's disease (PD), have been associated with impaired copper levels. In the present review, we describe the molecular mechanisms through which copper can exert its toxicity, by considering how it can interfere with other cellular processes known to play a role in PD, such as dopamine metabolism, oxidative stress, and α-synuclein aggregation. The recent experimental evidence that associates copper deficiency and the formation of superoxide dismutase 1 (SOD1) aggregates with the progression of PD is also discussed together with its therapeutic implication. Overall, the recent discoveries described in this review show how either copper deficiency or excessive levels can promote detrimental effects, highlighting the importance of preserving copper homeostasis and opening unexplored therapeutic avenues in the definition of novel disease-modifying drugs

    Bootstrap approaches for estimation and condence intervals of long memory processes.

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    In this work we investigate an alternative bootstrap approach based on a result of Ramsey (1974) and on the Durbin-Levinson algorithm to obtain surrogate series from linear Gaussian processes with long range dependence. We compare this bootstrap method with other existing procedures in a wide Monte Carlo experiment by estimating, parametrically and semiparametrically, the memory parameter d. We consider Gaussian and non-Gaussian processes to prove the robustness of the method to deviations from Normality. The approach is useful also to estimate condence intervals for the memory parameter d by improving the coverage level of the interval

    Linking ROS Levels to Autophagy: The Key Role of AMPK

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    Oxygen reactive species (ROS) are a group of molecules generated from the incomplete reduction of oxygen. Due to their high reactivity, ROS can interact with and influence the function of multiple targets, which include DNA, lipids, and proteins. Among the proteins affected by ROS, AMP-activated protein kinase (AMPK) is considered a major sensor of the intracellular energetic status and a crucial hub involved in the regulation of key cellular processes, like autophagy and lysosomal function. Thanks to these features, AMPK has been recently demonstrated to be able to perceive signals related to the variation of mitochondrial dynamics and to transduce them to the lysosomes, influencing the autophagic flux. Since ROS production is largely dependent on mitochondrial activity, through the modulation of AMPK these molecules may represent important signaling agents which participate in the crosstalk between mitochondria and lysosomes, allowing the coordination of these organelles' functions. In this review, we will describe the mechanisms through which ROS activate AMPK and the signaling pathways that allow this protein to affect the autophagic process. The picture that emerges from the literature is that AMPK regulation is highly tissue-specific and that different pools of AMPK can be localized at specific intracellular compartments, thus differentially responding to altered ROS levels. For this reason, future studies will be highly advisable to discriminate the specific contribution of the activation of different AMPK subpopulations to the autophagic pathway
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