852 research outputs found

    The nonlinear diffusion limit for generalized Carleman models: the initial-boundary value problem

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    Consider the initial-boundary value problem for the 2-speed Carleman model of the Boltzmann equation of the kinetic theory of gases set in some bounded interval with boundary conditions prescribing the density of particles entering the interval. Under the usual parabolic scaling, a nonlinear diffusion limit is established for this problem. In fact, the techniques presented here allow treating generalizations of the Carleman system where the collision frequency is proportional to some power of the macroscopic density, with exponent in [-1,1]

    1D nonlinear Fokker–Planck equations for fermions and bosons

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    AbstractWe obtain equilibration rates for nonlinear Fokker–Planck equations modelling the relaxation of fermion and boson gases. We show how the entropy method applies for quantifying explicitly the exponential decay towards Fermi–Dirac and Bose–Einstein distributions in the one-dimensional case

    Subclinical giant cell arteritis in polymyalgia rheumatica: Concurrent conditions or a common spectrum of inflammatory diseases?

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    Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common conditions in older adults. Their clinical connection has been recognized over time, with many patients experiencing both conditions separately, simultaneously or in temporal sequence to each other. Early GCA detection is essential to prevent vascular damage, but identifying subclinical GCA in PMR patients remains a challenge and routine screening is not standard practice. Subclinical GCA prevalence in newly diagnosed PMR patients ranges from 23 to 29%, depending on the screening method. Vessel wall imaging and temporal artery biopsy can detect subclinical GCA. Epidemiology and trigger factors show similarities between the two conditions, but PMR is more common than GCA. Genetic and pathogenesis studies reveal shared inflammatory mechanisms involving dendritic cells, pro-inflammatory macrophages, and an IL-6 signature. However, the inflammatory infiltrates differ, with extensive T cell infiltrates seen in GCA while PMR shows an incomplete profile of T cell and macrophage-derived cytokines. Glucocorticoid treatment is effective for both conditions, but the steroid requirements vary. PMR overall mortality might be similar to the general population, while GCA patients with aortic inflammatory aneurysms face increased mortality risk. The GCA-PMR association warrants further research. Considering their kinship, recently the term GCA-PMR Spectrum Disease (GPSD) has been proposed

    On-farm welfare assessment protocol for suckling piglets: A pilot study

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    Piglets experience welfare issues during the nursery phase. This pilot study aimed to test a protocol for identifying the main welfare issues in suckling piglets and to investigate relationships among animal-based indicators and management conditions. Litters (n = 134), composed of undocked and tail-docked piglets, were assessed at two farms. After birth, observations were made at the age of 7 days and 20 days. At each observation, housing conditions (HCs) were measured, and 13 animal-based indicators, modified from Welfare Quality, Classyfarm, Assurewel and others introduced ex novo, were recorded. A generalized linear mixed model was used, considering animal-based indicators as dependent variables and farm, piglets\u2019 age, tail docking and HCs as independent variables. The main welfare issues were lesions of the limb (32.6%) and the front area of the body (22.8%), a poor body condition score (BCS) (16.1%), ear lesions (15.5%), and tail lesions (9.7%). Negative social behaviour (e.g., fighting and biting) represented 7.0% of the active behaviour, with tail biting observed in 8.7% of the piglets. While lesions on the front areas of the body were mostly associated with the farm, tail lesions, low BCS, tear staining, and diarrhoea were associated with light and nest temperature (p < 0.05). In particular, tail biting increased with scarce light (p = 0.007). Tail docking did not influence any animal-based indicator except for tear staining which was higher in the tail-docked as compared to the undocked piglets (p = 0.05), increasing awareness on this practice as a source of negative emotion in piglets. The protocol tested may be a promising tool for assessing on-farm piglets\u2019 welfare

    The Role of PET in the Diagnosis and Disease Activity Assessment in Large Vessel Vasculitis

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    The role of 18F-fluorodeoxyglucose (FDG) positron emission tomography (18F-FDG PET) in the diagnosis of large vessel vasculitis (LVV) is well established. It permits us to assess the extent and the grade of vascular involvement and to rule out the other causes in clinical scenarios characterized by less specific symptoms. The advantages of 18F-FDG PET are far less clear in monitoring disease activity over time. Studies looking for the role of 18F-FDG PET as a potential biomarker had conflicting results and whether and when to repeat it during follow-up is based on clinical experience. A comprehensive assessment, including clinical, laboratory and morphological imaging is still required to monitor patients with large-vessel vasculitis over time. The aim of this review is to present more recent data about the utility of 18 F-FDG PET in the diagnosis and follow-up of LVV

    Follow-Up CT Patterns of Residual Lung Abnormalities in Severe COVID-19 Pneumonia Survivors: A Multicenter Retrospective Study

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    Prior studies variably reported residual chest CT abnormalities after COVID-19. This study evaluates the CT patterns of residual abnormalities in severe COVID-19 pneumonia survivors. All consecutive COVID-19 survivors who received a CT scan 5–7 months after severe pneumonia in two Italian hospitals (Reggio Emilia and Parma) were enrolled. Individual CT findings were retrospectively collected and follow-up CT scans were categorized as: resolution, residual non-fibrotic abnormalities, or residual fibrotic abnormalities according to CT patterns classified following standard definitions and international guidelines. In 225/405 (55.6%) patients, follow-up CT scans were normal or barely normal, whereas in 152/405 (37.5%) and 18/405 (4.4%) patients, non-fibrotic and fibrotic abnormalities were respectively found, and 10/405 (2.5%) had post-ventilatory changes (cicatricial emphysema and bronchiectasis in the anterior regions of upper lobes). Among non-fibrotic changes, either barely visible (n = 110/152) or overt (n = 20/152) ground-glass opacities (GGO), resembling non-fibrotic nonspecific interstitial pneumonia (NSIP) with or without organizing pneumonia features, represented the most common findings. The most frequent fibrotic abnormalities were subpleural reticulation (15/18), traction bronchiectasis (16/18) and GGO (14/18), resembling a fibrotic NSIP pattern. When multiple timepoints were available until 12 months (n = 65), residual abnormalities extension decreased over time. NSIP, more frequently without fibrotic features, represents the most common CT appearance of post-severe COVID-19 pneumonia

    Use of Neem oil and Hypericum perforatum for treatment of calcinosis-related skin ulcers in systemic sclerosis

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    Objective: This study evaluated Neem oil and Hypericum perforatum (Holoil®) for treatment of scleroderma skin ulcers related to calcinosis (SU-calc). Procedure: We retrospectively analyzed 21 consecutive systemic sclerosis (SSc) patients with a total of 33 SU-calcs treated daily with Holoil® cream compared with a control group of 20 patients with 26 SU-calcs. Holoil® was directly applied to skin lesions, while the control group received only standard medication. Results: Application of Holoil® either resulted in crushing and complete resolution of calcium deposits or facilitated sharp excision of calcinosis during wound care sessions in 27/33 cases (81.8%). Complete healing of SU-calc occurred in 15/33 (45%) of cases within a time period of 40.1 ± 16.3 (mean ± SD) days, while 18/33 (55%) of lesions improved in terms of size, erythema, fibrin and calcium deposits. Patients reported a reduction of pain (mean numeric rating scale 7.3 ± 1.9 at baseline versus 2.9 ± 1.4 at follow-up) The control group had longer healing times and a higher percentage of infections. Conclusions: The efficacy of local treatment with neem oil and Hypericum perforatum suggest that Holoil® could be a promising tool in the management of SSc SU-calc

    Epidemiology and management of interstitial lung disease in ANCA-associated vasculitis

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    Antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) is a group of systemic vasculitides that predominantly affect small vessels, including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Pulmonary involvement is frequently observed in AAV patients, with various possible phenotypes in the different diseases. In the last years, among the possible types of lung involvement, a growing interest has been addressed to the interstitial lung disease (ILD). Prevalence of ILD is higher in MPA than in GPA; in fact, ILD has been reported in up to 45% of MPA patients and in 23% of GPA. Anti-MPO antibodies are the main ANCA subtype associated to ILD, in about 46-71% of cases, while anti-PR3 antibodies are reported in 0-29% of patients. High resolution computed tomography (HRCT) frequently detects interstitial lung abnormalities in AAV, up to 66% of patients with MPA, even if with an unclear clinical relevance, specifically in asymptomatic patients. Ground glass opacities, mainly consistent with diffuse alveolar hemorrhage (DAH), are the most frequent finding in MPA patients, but reticulations, interlobular septal thickening and honeycombing are also reported. ILD significantly affects quality of life and survival, with mortality increased 2 to 4 times, particularly higher in MPA patients with pulmonary fibrosis. Currently, immunosuppressive therapy is considered also as a possible treatment of ILD. However, a careful evaluation of progression and severity of lung involvement, should guide the treatment decision in the single patient. In this review, we discuss the available evidence on clinical features, diagnostic work-up, prognosis and management of AAV-ILD
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