84 research outputs found
On the impact of serial dependence on penalized regression methods
This paper characterizes the impact of covariates serial dependence on the
non-asymptotic estimation error bound of penalized regressions (PRs). Focusing
on the direct relationship between the degree of cross-correlation of
covariates and the estimation error bound of PRs, we show that orthogonal or
weakly cross-correlated stationary AR processes can exhibit high spurious
correlations caused by serial dependence. In this respect, we study
analytically the density of sample cross-correlations in the case of two
orthogonal Gaussian AR(1) processes. Our results are validated by an extensive
simulation study. Furthermore, we introduce a new procedure to remedy spurious
correlations in a time series regime, applying PRs to pre-whitened (ARMA
filter) time series. We show that under mild assumptions our procedure allows
both to reduce the estimation error and to develop an effective forecasting
strategy. The estimation accuracy of our proposal is validated by means of
simulations and an empirical application based on a large monthly macroeconomic
data relative to the Euro Area economy
Modulation of the Senescence-Associated Inflammatory Phenotype in Human Fibroblasts by Olive Phenols
Senescent cells display an increase in the secretion of growth factors, inflammatory cytokines and proteolytic enzymes, termed the “senescence-associated-secretory-phenotype” (SASP), playing a major role in many age-related diseases. The phenolic compounds present in extra-virgin olive oil are inhibitors of oxidative damage and have been reported to play a protective role in inflammation-related diseases. Particularly, hydroxytyrosol and oleuropein are the most abundant and more extensively studied. Pre-senescent human lung (MRC5) and neonatal human dermal (NHDF) fibroblasts were used as cellular model to evaluate the effect of chronic (4–6 weeks) treatment with 1 μM hydroxytyrosol (HT) or 10 μM oleuropein aglycone (OLE) on senescence/inflammation markers. Both phenols were effective in reducing β-galactosidase-positive cell number and p16 protein expression. In addition, senescence/inflammation markers such as IL-6 and metalloprotease secretion, and Ciclooxigenase type 2 (COX-2) and α-smooth-actin levels were reduced by phenol treatments. In NHDF, COX-2 expression, Nuclear Factor κ-light-chain-enhancer of activated B cells (NFκB) protein level and nuclear localization were augmented with culture senescence and decreased by OLE and HT treatment. Furthermore, the inflammatory effect of Tumor Necrosis Factor α (TNFα) exposure was almost completely abolished in OLE- and HT-pre-treated NHDF. Thus, the modulation of the senescence-associated inflammatory phenotype might be an important mechanism underlying the beneficial effects of olive oil phenols
TCT-845 Femoral Approach with Systematic Use of FemoSeal™ Closure Device Compared to Radial Approach in Primary Angioplasty: a Propensity-matched Comparison
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Prodromal non-motor symptoms of Parkinson’s disease
The motor symptoms of Parkinson’s disease (PD), bradykinesia, muscular rigidity, and tremor depend upon degeneration of the dopaminergic neurons in the substantia nigra pars compacta. Recent neuropathological studies show that the Lewy bodies, the intraneuronal landmark of PD, accumulate in several neuronal cell types in the brain. An ascending gradient of pathological involvement, from the medulla oblongata to neocortical areas has been reported. Thus the original view of PD as a disease characterized by selective damage of the dopaminergic neurons in the mesencephalon should be updated into the concept of a severe multisystemic neurodegenerative disorder. Additionally, the neuropathological alterations outside the substantia nigra are soundly correlated with the non-motor symptoms of PD. As a result of these findings, interest is growing in the identification of prodromal non-motor symptoms of PD. Indeed, data from the literature suggest that autonomic disturbances, olfactory dysfunctions, depression and sleep disorders (in particular REM-sleep behavior disorder) may represent prodromal non-motor symptoms of PD. Several tests are available to detect most of these symptoms. Thus, the identification of prodromal non-motor symptoms may contribute to the precocious diagnosis of PD, and might be useful in the future to test the efficacy of neuroprotective agents
Partial block by riluzole of muscle sodium channels in myotubes from amyotrophic lateral sclerosis patients.
International audienceDenervated muscles undergo fibrillations due to spontaneous activation of voltage-gated sodium (Na(+)) channels generating action potentials. Fibrillations also occur in patients with amyotrophic lateral sclerosis (ALS). Riluzole, the only approved drug for ALS treatment, blocks voltage-gated Na(+) channels, but its effects on muscle Na(+) channels and fibrillations are yet poorly characterized. Using patch-clamp technique, we studied riluzole effect on Na(+) channels in cultured myotubes from ALS patients. Needle electromyography was used to study fibrillation potentials (Fibs) in ALS patients during riluzole treatment and after one week of suspension. Patients were clinically characterized in all recording sessions. In myotubes, riluzole (1 μM, a therapeutic concentration) reduced Na(+) current by 20%. The rate of rise and amplitude of spikes evoked by depolarizing stimuli were also reduced. Fibs were detected in all patients tested during riluzole treatment and riluzole washout had no univocal effect. Our study indicates that, in human myotubes, riluzole partially blocks Na(+) currents and affects action potentials but does not prevent firing. In line with this in vitro finding, muscle Fibs in ALS patients appear to be largely unaffected by riluzole
Definition of physical-dynamic parameters in circular kick in Muay Thai through latest generation inertial sensors with a critical review of the literature
In recent years, the study of movement analysis with the application of dedicated advanced technologies, such as inertial technologies, has also become essential in scientific research of sports disciplines such as martial arts and combat sports, to better define the real dynamics of technical components in order to adapt the training design. A great number of studies in the literature have focused on the kinematics of circular kick in combat sport and martial arts but a relatively small number have focused on the kinetic and kinematic analysis of Muay Thai and especially its circular kick technique. This study aims to highlight instrumentally the quality of circular kick gesture and through which segmental motor dynamics it achieves its greatest effectiveness, evaluating the accelerations and execution times of the different body segments involved in technical execution itself obviously in a performative sense. It is important to note that the inertial data shows that both knee and ankle have an increasing linear velocity greater than the hip in the preparation and execution phase, while for the angular velocity in the execution phase it is the hip that has higher acceleration than the knee and ankle. These results, therefore, highlight the basic importance of intra-articular and intramuscular coordination processes that allow or not linearity and fluidity of movements that are the basis to obtain maximum intersegmental performance in order to deliver maximum acceleration in the apical point of the shot and thus have the maximum effectiveness of hit and therefore the optimal performance
Morpho-Physiological Responses of Three Italian Olive Tree (Olea europaea L.) Cultivars to Drought Stress
Water scarcity in agriculture can limit crop production and trigger the need for more effective water resource management. As a result, it is critical to identify new crop genotypes that are more drought tolerant and perform better under low irrigation or even rain-fed conditions. The olive tree is a high-value crop that is well adapted to dry Mediterranean conditions. However, different genotypes may have developed different mechanisms of tolerance to water stress. To investigate such mechanisms, we examined three Italian olive cultivars (‘Giarraffa’, ‘Leccino’, and ‘Maurino’) grown in a greenhouse under drought stress. We found that single genotypes responded differently to the drought, though not all parameters revealed significant differences. The first major difference among the cultivars was in transpiration: the lower stomatal density and stomatal conductance of ‘Giarraffa’ allow this cultivar to use water more conservatively. In parallel with the reduction in stomatal and mesophyll conductance, the drought-stressed group of ‘Giarraffa’ maintained the electron transport rate and effective efficiency levels of photosystem II similar to those of the control until the fourth week of stress. The fluorescence parameters revealed the earlier closure of reaction photosynthetic centres in ‘Leccino’. Finally, the higher rate of electrolyte leakage in ‘Maurino’ indicated a significant ions loss in this cultivar when it was subjected to the drought. Both water management under stress conditions and the effect of drought on photosynthesis make ‘Giarraffa’ interesting to researchers studying its use in breeding or water-saving programmes
Life Food Diet: A Protocol for the Promotion of the Mediterranean Diet
Background: The potential benefits for the health arising from the Mediterranean Diet (MD) are supported by several scientific evidences: the MD helps to reduce the LDL cholesterol levels, to prevent and/or control conditions dramatically spread out such as diabetes, overweight and obesity. A healthy and balanced diet constitutes an incisive instrument of preventing the chronical diseases, the cardiovascular risk factors and certain cancers.
Objectives: The “Life Foof Diet” (LFD) Project is aimed at promoting worldwide the MD, along with all benefits arising out from the latter for the Public Health. The project involves several professionals and sectors, within the context of a multidisciplinary cooperation, in which culture/research and catering/food sector can ensure the quality of the products.
Methods: The cooperation among the players operating in the food sector, operators of the catering sector and companies of the entire Mediterranean Sea area, in addition to the endorsement of the Sicily Region shall be required. The certification so-called “Life Food Diet” can be granted to products which complies with the MD and which meet the specific requirements imposed by the applicable regulation.
The intervention: The products shall be subject to periodic checks to be implemented by the University of the countries involved in the project. The certification will be also issued in favor of restaurateurs, restaurants, entities, collective catering etc., which express the value under the MD, by demonstrating the use of LFD certified products. Trainings (Master, refresher trainings, Master Class etc.), as well as optional teaching activities at the universities of the countries involved - that allow to change the way of communicating about the human nutrition, which is an indispensable tool for prevention - shall be established.
Conclusions: The establishment of the LFD certification will improve the promotion of a proper nutrition, by favoring virtuous lifestyles allowing the decrease of the economic charge of the chronic degenerative diseases
Chronic resveratrol treatment inhibits MRC5 fibroblast SASP-related pro-tumoral effects on melanoma cells
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