311 research outputs found

    Spontaneous internal carotid artery rupture during neck dissection in osteogenesis imperfecta patient.

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    Several connective tissue disorders are associated with vascular wall abnormalities, including spontaneous dissection of the cervical arteries. Osteogenesis imperfecta (OI) is a hereditary disorder, with rare neurovascular complications, which potentially lead to life-threatening events.We presented a case of spontaneous internal carotid artery (ICA) rupture that occurred in a 52-year-old-woman, suffering from OI type I, and who underwent a bilateral modified radical neck dissection (mRND) plus total thyroidectomy for a T4aN1b thyroid cancer. During mRND, an ICA's spontaneous rupture occurred.Histopathologic report suggested a structural defect of the arterial wall without cancer infiltration. The patient did not experience any neurologic complications.Head and neck surgeons have to be aware about early clinical recognition of possible cervical vascular abnormalities, in patients with connective tissue disorders, potentially responsible for dramatic vascular rupture during cervical surgical procedures

    La reputazione come vettore di fiducia nei sistemi socio-economici: alcuni risultati sperimentali

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    This paper presents the results of some laboratory experiments on the relevance of reputation for the emergence of trust and cooperation in socio-economic interaction. We have extended a repeated investment game adding new treatments where reputation is taken more explicitly into account than in the present literature. We compare treatments where the investor and the trustee rate each other and treatments where the investor and the trustee are rated by a third party. The results show that: (i) reputation impacts the behaviour of individuals even when it has no consequence on their payoffs; (ii) third party reputation positively affects cooperation by encapsulating trust; (iii) some differences in the reputation mechanism can generate different cooperation outcomes. These results have interesting implications on the recent sociological debate on the normative pillars of markets

    Comparative chondrogenesis of human cells in a 3D integrated experimental/computational mechanobiology model

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    We present an integrated experimental–computational mechanobiology model of chondrogenesis. The response of human articular chondrocytes to culture medium perfusion, versus perfusion associated with cyclic pressurisation, versus non-perfused culture, was compared in a pellet culture model, and multiphysic computation was used to quantify oxygen transport and flow dynamics in the various culture conditions. At 2 weeks of culture, the measured cell metabolic activity and the matrix content in collagen type II and aggrecan were greatest in the perfused+ pressurised pellets. The main effects of perfusion alone, relative to static controls, were to suppress collagen type I and GAG contents, which were greatest in the non-perfused pellets. All pellets showed a peripheral layer of proliferating cells, which was thickest in the perfused pellets, and most pellets showed internal gradients in cell density and matrix composition. In perfused pellets, the computed lowest oxygen concentration was 0.075mM (7.5% tension), the maximal oxygen flux was 477.5 nmol/m2/s and the maximal fluid shear stress, acting on the pellet surface, was 1.8mPa (0.018 dyn/cm2). In the non-perfused pellets, the lowest oxygen concentration was 0.003mM (0.3% tension) and the maximal oxygen flux was 102.4nmol/m2/s.Alocal correlationwas observed, between the gradients in pellet properties obtained from histology, and the oxygen fields calculated with multiphysic simulation. Our results showup-regulation of hyalinematrix protein production by human chondrocytes in response to perfusion associated with cyclic pressurisation. These results could be favourably exploited in tissue engineering applications

    Atomic and molecular data for spacecraft re-entry plasmas

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    The modeling of atmospheric gas, interacting with the space vehicles in re-entry conditions in planetary exploration missions, requires a large set of scattering data for all those elementary processes occurring in the system. A fundamental aspect of re-entry problems is represented by the strong non-equilibrium conditions met in the atmospheric plasma close to the surface of the thermal shield, where numerous interconnected relaxation processes determine the evolution of the gaseous system towards equilibrium conditions. A central role is played by the vibrational exchanges of energy, so that collisional processes involving vibrationally excited molecules assume a particular importance. In the present paper, theoretical calculations of complete sets of vibrationally state-resolved cross sections and rate coefficients are reviewed, focusing on the relevant classes of collisional processes: resonant and non-resonant electron-impact excitation of molecules, atom-diatom and molecule-molecule collisions as well as gas-surface interaction. In particular, collisional processes involving atomic and molecular species, relevant to Earth (N2, O2, NO), Mars (CO2, CO, N2) and Jupiter (H2, He) atmospheres are considered

    Relationship between herpes simplex virus-1-specific antibody titers and cortical brain damage in Alzheimer's disease and amnestic mild cognitive impairment

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    This work was supported by 2012–2014 Ricerca Corrente (Italian Ministry of Health).Alzheimer's disease (AD) is a multifactorial disease with a still barely understood etiology. Herpes simplex virus 1 (HSV-1) has long been suspected to play a role in the pathogenesis of AD because of its neurotropism, high rate of infection in the general population, and life-long persistence in neuronal cells, particularly in the same brain regions that are usually altered in AD. The goal of this study was to evaluate HSV-1-specific humoral immune responses in patients with a diagnosis of either AD or amnestic mild cognitive impairment (aMCI), and to verify the possible relation between HSV-1-specific antibody (Ab) titers and cortical damage; results were compared to those obtained in a group of healthy controls (HC). HSV-1 serum IgG titers were measured in 225 subjects (83 AD, 68 aMCI, and 74 HC). HSV-specific Ab avidity and cortical gray matter volumes analyzed by magnetic resonance imaging (MRI) were evaluated as well in a subgroup of these individuals (44 AD, 23 aMCI, and 26 HC). Results showed that, whereas HSV-1 seroprevalence and IgG avidity were comparable in the three groups, increased Ab titers (p < 0.001) were detected in AD and aMCI compared to HC. Positive significant correlations were detected in AD patients alone between HSV-1 IgG titers and cortical volumes in orbitofrontal (region of interest, ROI1 RSp0.56; p = 0.0001) and bilateral temporal cortices (ROI2 RSp0.57; p < 0.0001; ROI3 RSp0.48; p = 0.001); no correlations could be detected between IgG avidity and MRI parameters. Results herein suggest that a strong HSV-1-specific humoral response could be protective toward AD-associated cortical damage.Publisher PDFPeer reviewe

    Atomic and molecular data for spacecraft re-entry plasmas

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    The modeling of atmospheric gas, interacting with the space vehicles in re-entry conditions in planetary exploration missions, requires a large set of scattering data for all those elementary processes occurring in the system. A fundamental aspect of re-entry problems is represented by the strong non-equilibrium conditions met in the atmospheric plasma close to the surface of the thermal shield, where numerous interconnected relaxation processes determine the evolution of the gaseous system towards equilibrium conditions. A central role is played by the vibrational exchanges of energy, so that collisional processes involving vibrationally excited molecules assume a particular importance. In the present paper, theoretical calculations of complete sets of vibrationally state-resolved cross sections and rate coefficients are reviewed, focusing on the relevant classes of collisional processes: resonant and non-resonant electron-impact excitation of molecules, atom-diatom and molecule-molecule collisions as well as gas-surface interaction. In particular, collisional processes involving atomic and molecular species, relevant to Earth (N-2, O-2, NO), Mars (CO2, CO, N-2) and Jupiter (H-2, He) atmospheres are considered

    Hip viscosupplementation under ultra-sound guidance riduces NSAID consumption in symptomatic hip osteoarthritis patients in a long follow-up. Data from Italian registry.

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    Introduction: Non-steroidal anti-inflammatory drugs (NSAIDs) consumption is strictly related to a high gastrointestinal and cardiovascular mortality and morbidity rate. Osteoarthritis Research Society International (OARSI) recommendations in patients with symptomatic hip or knee OA stated that NSAIDs should be used at the lowest effective dose but their long-term use should be avoided if possible. OARSI guidelines for the treatment of the hip OA include the use of viscosupplementation, which aims to restore physiological and Theological features of the synovial fluid. Objective: Aim of this multicentric, open and retrospective study is to investigate if NSAID consumption may be reduced by the use of ultrasound-guided intra-articular injection of several hyaluronic acid (HA) products in hip joint administered in patients affected by symptomatic hip OA. Materials and Methods: Patients affected by mono or bilateral symptomatic hip OA according to American Rheumatology Association (ARA) criteria, radiological OA graded II-IV (Kellgren and Lawrence) entered the study and were administered with ultrasound-guided intra-articular injection of hyaluronic acid products. As a primary endpoint, consumption of NSAIDs was evaluated by recording the number of days a month (range 0-30) the patient had used NSAID during the previous month, reported at each visit during the 24 months follow-up period. Secondary endpoints included further analysis for subgroups of patients categorized for Lequesne index score, Kellgren-Lawrence score, pain visual analogue scale (VAS) score, ultrasound pattern, age, hyaluronic acid used. Results: 2343 patients entered the study. Regarding primary endpoint, the consumption of NSAIDs was reduced of 48.2% at the third month when compared with baseline values. This sparing effect increased at 12th and 24th month with a reduction respectively of 50% and 61% in comparison to baseline values. These differences were statistically significant. Conclusions: These data point out that intraarticular hyaluronan preparations provide OA pain relief and reduce NSAIDs consumption in a large cohort of patients for a long period of follow-up. Multiple courses of viscosupplementation (vs) are required to maintain low dose of NSAID consumption over time. NSAIDs consumption is strictly related to an high gastrointestinal and cardiovascular mortality and morbidity rate, instead HA intra-articular treatment is well tolerated and is associated with a low incidence of adverse effects. For these reasons further studies evaluating cost-effectiveness and cost-utility of VS in the management of hip OA are required

    An anatomy-based lumped parameter model of cerebrospinal venous circulation: can an extracranial anatomical change impact intracranial hemodynamics?

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    Background The relationship between extracranial venous system abnormalities and central nervous system disorders has been recently theorized. In this paper we delve into this hypothesis by modeling the venous drainage in brain and spinal column areas and simulating the intracranial flow changes due to extracranial morphological stenoses. Methods A lumped parameter model of the cerebro-spinal venous drainage was created based on anatomical knowledge and vessels diameters and lengths taken from literature. Each vein was modeled as a hydraulic resistance, calculated through Poiseuille’s law. The inputs of the model were arterial flow rates of the intracranial, vertebral and lumbar districts. The effects of the obstruction of the main venous outflows were simulated. A database comprising 112 Multiple Sclerosis patients (Male/Female = 42/70; median age ± standard deviation = 43.7 ± 10.5 years) was retrospectively analyzed. Results The flow rate of the main veins estimated with the model was similar to the measures of 21 healthy controls (Male/Female = 10/11; mean age ± standard deviation = 31 ± 11 years), obtained with a 1.5 T Magnetic Resonance scanner. The intracranial reflux topography predicted with the model in cases of internal jugular vein diameter reduction was similar to those observed in the patients with internal jugular vein obstacles. Conclusions The proposed model can predict physiological and pathological behaviors with good fidelity. Despite the simplifications introduced in cerebrospinal venous circulation modeling, the key anatomical feature of the lumped parameter model allowed for a detailed analysis of the consequences of extracranial venous impairments on intracranial pressure and hemodynamics
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