110 research outputs found

    Existence and regularity results for viscous Hamilton–Jacobi equations with Caputo time-fractional derivative

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    We study existence, uniqueness and regularity properties of classical solutions to viscous Hamilton–Jacobi equations with Caputo time-fractional derivative. Our study relies on a combination of a gradient bound for the time-fractional Hamilton–Jacobi equation obtained via nonlinear adjoint method and sharp estimates in Sobolev and Hölder spaces for the corresponding linear problem

    A Note on the Strong Maximum Principle for Fully Nonlinear Equations on Riemannian Manifolds

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    We investigate strong maximum (and minimum) principles for fully nonlinear second-order equations on Riemannian manifolds that are non-totally degenerate and satisfy appropriate scaling conditions. Our results apply to a large class of nonlinear operators, among which Pucci\u2019s extremal operators, some singular operators such as those modeled on the p- and 1e-Laplacian, and mean curvature-type problems. As a byproduct, we establish new strong comparison principles for some second-order uniformly elliptic problems when the manifold has nonnegative sectional curvature

    Interleukin-1beta and glutamate activate the NF-kappaB/Rel binding site from the regulatory region of the Amyloid Precursor Protein gene in primary neuronal cultures

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    We originally reported that members of the family of transcription factors NF-kappaB/Rel can specifically recognize two identical sequences, referred to as APPkappaB sites, which are present in the 5'-regulatory region of the APP gene. Here we show that the APPkappaB sites interact specifically with a complex which contains one of the subunits of the family, defined as p50 protein, and that they act as positive modulators of gene transcription in cells of neural origin. Additionally, the nuclear complex specifically binding to the APPkappaB sites is constitutively expressed in primary neurons from rat cerebellum and it is up-regulated in response to both the inflammatory cytokine interleukin-1beta (IL-1beta) and the excitatory amino acid glutamate. Since IL-1, whose levels are known to be induced in brain of individuals affected by Alzheimer's disease, and glutamate, are stimuli which have been regarded as major actors on the stage of neurodegenerative processes, we believe our evidence as potentially relevant for understanding the neuropathology associated with Alzheimer's disease

    Satellite-detected tropospheric nitrogen dioxide and spread of SARS-CoV-2 infection in Northern Italy

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    Following the outbreak of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) last December 2019 in China, Italy was the first European country to be severely affected, with the first local case diagnosed on 20 February 2020. The virus spread quickly, particularly in the North of Italy, with three regions (Lombardy, Veneto and Emilia-Romagna) being the most severely affected. These three regions accounted for >80% of SARS-CoV-2 positive cases when the tight lockdown was established (March 8). These regions include one of Europe's areas of heaviest air pollution, the Po valley. Air pollution has been recently proposed as a possible risk factor of SARS-CoV-2 infection, due to its adverse effect on immunity and to the possibility that polluted air may even carry the virus. We investigated the association between air pollution and subsequent spread of the SARS-CoV-2 infection within these regions. We collected NO2 tropospheric levels using satellite data available at the European Space Agency before the lockdown. Using a multivariable restricted cubic spline regression model, we compared NO2 levels with SARS-CoV-2 infection prevalence rate at different time points after the lockdown, namely March 8, 22 and April 5, in the 28 provinces of Lombardy, Veneto and Emilia-Romagna. We found little association of NO2 levels with SARS-CoV-2 prevalence up to about 130 μmol/m2, while a positive association was evident at higher levels at each time point. Notwithstanding the limitations of the use of aggregated data, these findings lend some support to the hypothesis that high levels of air pollution may favor the spread of the SARS-CoV-2 infection

    Opposing Roles for NF-κB/Rel Factors p65 and c-Rel in the Modulation of Neuron Survival Elicited by Glutamate and Interleukin-1β

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    The nuclear transcription factors NF-kappaB/Rel have been shown to function as key regulators of either cell death or survival in neuronal cells. Here, we investigated whether selective activation of diverse NF-kappaB/Rel family members might lead to distinct effects on neuron viability. In both cultured rat cerebellar granule cells and mouse hippocampal slices, we examined NF-kappaB/Rel activation induced by two opposing modulators of cell viability: 1) interleukin-1beta (IL-1beta), which promotes neuron survival and 2) glutamate, which can elicit toxicity. IL-1beta produced a prolonged stimulation of NF-kappaB/Rel factors by inducing both IkappaBalpha and IkappaBbeta degradation. Glutamate produced a delayed and transient activation of NF-kappaB/Rel, which was associated with a brief loss of IkappaBalpha. Moreover, IL-1beta activated the p50, p65, and c-Rel subunits of NF-kappaB/Rel, whereas glutamate activated only the p50 and p65 proteins. The inhibition of NF-kappaB/Rel protein expression by antisense oligonucleotides in cerebellar granule cells showed that p65 was involved in glutamate-mediated cell death, whereas c-Rel was essential for IL-1beta-preserved cell survival. Furthermore, the depletion of c-Rel in cultured neurons as well as in the hippocampus from the c-Rel(-/-) mouse converted the IL-1beta effect into toxicity. These findings suggest that, within a single neuron, the balance between cell death and survival in response to external stimuli may rely on the activation of distinct NF-kappaB/Rel proteins

    A multi-criteria approach for the selection of wastewater treatment systems

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    The inefficiency of Wastewater Treatment Systems (WTS) might be a source of hydrological and environmental pollution, and it also causes problems to public health. The advances of technology have contributed to the development of a diversity of new WTS, but it generates a gap for decision-making regards to the correct use of these treatment systems, with a high number of available alternatives, not easily measurable and often presenting conflicting criteria. In this context, this work presents a literature review aiming to identify relevant economic, social, technical and environmental criteria, which can be used in the selection of WTS. Thus, 48 criteria were identified, as well and their importance was ranked according to a group of academics. Furthermore, an illustrative application was conducted considering 20 available WTS and 12 criteria. The ELECTRE 11 method was used to rank and allocate the most suitable WTS. This research contributes with a multi-criteria model for the evaluation of WTS and to show its relevance in a real world situation

    Associations between mortality from COVID-19 in two Italian regions and outdoor air pollution as assessed through tropospheric nitrogen dioxide

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    After the appearance of COVID-19 in China last December 2019, Italy was the first European country to be severely affected by the outbreak. The first diagnosis in Italy was on February 20, 2020, followed by the establishment of a light and a tight lockdown on February 23 and on March 8, 2020, respectively. The virus spread rapidly, particularly in the North of the country in the ‘Padan Plain’ area, known as one of the most polluted regions in Europe. Air pollution has been recently hypothesized to enhance the clinical severity of SARS-CoV-2 infection, acting through adverse effects on immunity, induction of respiratory and other chronic disease, upregulation of viral receptor ACE-2, and possible pathogen transportation as a virus carrier. We investigated the association between air pollution and subsequent COVID-19 mortality rates within two Italian regions (Veneto and Emilia-Romagna). We estimated ground-level nitrogen dioxide through its tropospheric levels using data available from the Sentinel-5P satellites of the European Space Agency Copernicus Earth Observation Programme before the lockdown. We then examined COVID-19 mortality rates in relation to the nitrogen dioxide levels at three 14-day lag points after the lockdown, namely March 8, 22 and April 5, 2020. Using a multivariable negative binomial regression model, we found an association between nitrogen dioxide and COVID-19 mortality. Although ecological data provide only weak evidence, these findings indicate an association between air pollution levels and COVID-19 severity

    The Incidence of Adjacent Segment Degeneration after Cervical Disc Arthroplasty (CDA): A Meta Analysis of Randomized Controlled Trials

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    Cervical disc arthroplasty is being used as an alternative degenerative disc disease treatment with fusion of the cervical spine in order to preserve motion. However, whether replacement arthoplasty in the spine achieves its primary patient centered objective of lowering the frequency of adjacent segment degeneration is not verified yet.We conducted a meta-analysis according to the guidelines of the Cochrane Collaboration using databases including PubMed, Cochrane Central Register of Controlled Trials and Embase. The inclusion criteria were: 1) Randomized, controlled study of degenerative disc disease of the cervical spine involving single segment or double segments using Cervical disc arthroplasty (CDA) with anterior cervical discectomy and fusion (ACDF) as controls; 2) A minimum of two-year follow-up using imaging and clinical analyses; 3) Definite diagnostic evidences for "adjacent segment degeneration" and "adjacent segment disease"; 4) At least a minimum of 30 patients per population. Two authors independently selected trials; assessed methodological quality, extracted data and the results were pooled.No study has specifically compared the results of adjacent segment degenerative; Two papers describing 140 patients with 162 symptomatic cervical segment disorders and compared the rate of postoperative adjacent segment disease development between CDA and ACDF treatments, three publications describing the rate of adjacent-segment surgery including 1273 patients with symptomatic cervical segments. The result of the meta-analysis indicates that there were fewer the rate of adjacent segment disease and the rate for adjacent-segment surgery comparing CDA with ACDF, but the difference was not statistically significant.Based on available evidence, it cannot be concluded, that CDA can significantly reduce the postoperative rate of the adjacent segment degenerative and adjacent segment disease. However, due to some limitations, the results of this meta-analysis should be cautiously accepted, and further studies are needed

    The critical care management of poor-grade subarachnoid haemorrhage

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