158 research outputs found

    Stochastic Claims Reserve in the Healthcare System: A Methodology Applied to Italian Data

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    One of the challenges in the healthcare sector is making accurate forecasts across insurance years for claims reserve. Healthcare claims present huge variability and heterogeneity influenced by random decisions of the courts and intrinsic characteristics of the damaged parties, which makes traditional methods for estimating reserves inadequate. We propose a new methodology to estimate claim reserves in the healthcare insurance system based on generalized linear models using the Overdispersed Poisson distribution function. In this context, we developed a method to estimate the parameters of the quasi-likelihood function using a Gauss–Newton algorithm optimized through a genetic algorithm. The genetic algorithm plays a crucial role in glimpsing the position of the global minimum to ensure a correct convergence of the Gauss–Newton method, where the choice of the initial guess is fundamental. This methodology is applied as a case study to the healthcare system of the Tuscany region. The results were validated by comparing them with state-of-the-art measurement of the confidence intervals of the Overdispersed Poisson distribution parameters with better outcomes. Hence, local healthcare authorities could use the proposed and improved methodology to allocate resources dedicated to healthcare and global management

    AFM, ESEM, TEM, and CLSM in liposomal characterization: a comparative study

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    An outstanding aspect of pharmaceutical nanotechnology lies in the characterization of nanocarriers for targeting of drugs and other bioactive agents. The development of microscopic techniques has made the study of the surface and systems architecture more attractive. In the field of pharmaceutical nanosystems, researchers have collected vital information on size, stability, and bilayer organization through the microscopic characterization of liposomes. This paper aims to compare the results obtained by atomic force microscopy, environmental scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy to point out the limits and advantages of these applications in the evaluation of vesicular systems. Besides this comparative aim, our work proposes a simple confocal laser scanning microscopy procedure to rapidly and easily detect the liposomal membrane

    Apoferritin nanocage as streptomycin drug reservoir: Technological optimization of a new drug delivery system

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    The aim of this study is to formulate and characterize streptomycin-loaded apoferritin nanoparticles (ApoStrep NPs) for their potential therapeutic use in bacterial resistant infections (i.e. tuberculosis). ApoStrep NPs were prepared by disassembly/reassembly process via pH method and changing apoferritin/drug molar ratio, purified by dialyses process also associated with gel filtration chromatography and characterized in their chemico-physical and technological parameters as yield, size distribution, polidispersivity, morphology, internal structure, zeta potential and loading efficacy. The results showed that spherical reproducible NPs could be obtained by using apoferritin/drug molar ratio lower than 1:25 and purification based on the combination of dialysis and gel filtration chromatography. Photon correlation spectroscopy, Uv–visible detection and electron microscopy showed the maintenance of the native apoferritin chemico-physical properties and structure. When formulated with apoferritin/drug 1:10 and 1:25 molar ratio, ApoStrep NPs showed remarkable encapsulation efficacy (35% and 28%, respectively) along with kinetic profile of drug delivery, approximately 15% at 37 °C in 72 h, as evidenced by “in vitro” release experiments

    Proteome-wide observation of the phenomenon of life on the edge of solubility.

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    To function effectively proteins must avoid aberrant aggregation, and hence they are expected to be expressed at concentrations safely below their solubility limits. By analyzing proteome-wide mass spectrometry data of Caenorhabditis elegans, however, we show that the levels of about three-quarters of the nearly 4,000 proteins analyzed in adult animals are close to their intrinsic solubility limits, indeed exceeding them by about 10% on average. We next asked how aging and functional self-assembly influence these solubility limits. We found that despite the fact that the total quantity of proteins within the cellular environment remains approximately constant during aging, protein aggregation sharply increases between days 6 and 12 of adulthood, after the worms have reproduced, as individual proteins lose their stoichiometric balances and the cellular machinery that maintains solubility undergoes functional decline. These findings reveal that these proteins are highly prone to undergoing concentration-dependent phase separation, which on aging is rationalized in a decrease of their effective solubilities, in particular for proteins associated with translation, growth, reproduction, and the chaperone system

    Platelet Function Testing in Patients with Acute Ischemic Stroke: An Observational Study

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    Background: The measurement of platelet reactivity in patients with stroke undergoing antiplatelet therapies is not commonly performed in clinical practice. We assessed the prevalence of therapy responsiveness in patients with stroke and further investigated differences between patients on prevention therapy at stroke onset and patients naive to antiplatelet medications. We also sought differences in responsiveness between etiological subtypes and correlations between Clopidogrel responsiveness and genetic polymorphisms. Methods: A total of 624 stroke patients on antiplatelet therapy were included. Two different groups were identified: "non-naive patients", and "naive patients". Platelet function was measured with multiple electrode aggregometry, and genotyping assays were used to determine CYP2C19 polymorphisms. Results: Aspirin (ASA) responsiveness was significantly more frequent in naive patients compared with non-naive patients (94.9% versus 82.6%, P < .0010). A better responsiveness to ASA compared with Clopidogrel or combination therapy was found in the entire population (P < .0010), in non-naive patients (P < .0253), and in naive patients (P < .0010). Multivariate analysis revealed a strong effect of Clopidogrel as a possible "risk factor" for unresponsiveness (odds ratio 3.652, P < .0001). No difference between etiological subgroups and no correlations between responsiveness and CYP2C19 polymorphisms were found. Conclusion: In our opinion, platelet function testing could be potentially useful in monitoring the biological effect of antiplatelet agents. A substantial proportion of patients with stroke on ASA were "resistant", and the treatment with Clopidogrel was accompanied by even higher rates of unresponsiveness. Longitudinal studies are needed to assess whether aggregometry might supply individualized prognostic information and whether it can be considered a valid tool for future prevention strategies

    Chronic cholesterol administration to the brain supports complete and long-lasting cognitive and motor amelioration in Huntington's disease

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    : Evidence that Huntington's disease (HD) is characterized by impaired cholesterol biosynthesis in the brain has led to strategies to increase its level in the brain of the rapidly progressing R6/2 mouse model, with a positive therapeutic outcome. Here we tested the long-term efficacy of chronic administration of cholesterol to the brain of the slowly progressing zQ175DN knock-in HD mice in preventing ("early treatment") or reversing ("late treatment") HD symptoms. To do this we used the most advanced formulation of cholesterol loaded brain-permeable nanoparticles (NPs), termed hybrid-g7-NPs-chol, which were injected intraperitoneally. We show that one cycle of treatment with hybrid-g7-NPs-chol, administered in the presymptomatic ("early treatment") or symptomatic ("late treatment") stages is sufficient to normalize cognitive defects up to 5 months, as well as to improve other behavioral and neuropathological parameters. A multiple cycle treatment combining both early and late treatments ("2 cycle treatment") lasting 6 months generates therapeutic effects for more than 11 months, without severe adverse reactions. Sustained cholesterol delivery to the brain of zQ175DN mice also reduces mutant Huntingtin aggregates in both the striatum and cortex and completely normalizes synaptic communication in the striatal medium spiny neurons compared to saline-treated HD mice. Furthermore, through a meta-analysis of published and current data, we demonstrated the power of hybrid-g7-NPs-chol and other strategies able to increase brain cholesterol biosynthesis, to reverse cognitive decline and counteract the formation of mutant Huntingtin aggregates. These results demonstrate that cholesterol delivery via brain-permeable NPs is a therapeutic option to sustainably reverse HD-related behavioral decline and neuropathological signs over time, highlighting the therapeutic potential of cholesterol-based strategies in HD patients. DATA AVAILABILITY: This study does not include data deposited in public repositories. Data are available on request to the corresponding authors

    Performance of the CMS Cathode Strip Chambers with Cosmic Rays

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    The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

    Thrombolysis in stroke patients with elevated inflammatory markers.

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    OBJECTIVE To investigate the prognostic value of white blood cell count (WBC) on functional outcome, mortality and bleeding risk in stroke patients treated with intravenous thrombolysis (IVT). METHODS In this prospective multicenter study from the TRISP registry, we assessed the association between WBC on admission and 3-month poor outcome (modified Rankin Scale 3-6), mortality and occurrence of symptomatic intracranial hemorrhage (sICH; ECASS-II-criteria) in IVT-treated stroke patients. WBC was used as continuous and categorical variable distinguishing leukocytosis (WBC > 10 × 109/l) and leukopenia (WBC  10 mg/l) on outcomes. RESULTS Of 10,813 IVT-treated patients, 2527 had leukocytosis, 112 leukopenia and 8174 normal WBC. Increasing WBC (by 1 × 109/l) predicted poor outcome (ORadjusted 1.04[1.02-1.06]) but not mortality and sICH. Leukocytosis was independently associated with poor outcome (ORadjusted 1.48[1.29-1.69]) and mortality (ORadjusted 1.60[1.35-1.89]) but not with sICH (ORadjusted 1.17[0.94-1.45]). Leukopenia did not predict any outcome. In a subgroup, combined leukocytosis and elevated CRP had the strongest association with poor outcome (ORadjusted 2.26[1.76-2.91]) and mortality (ORadjusted 2.43[1.86-3.16]) when compared to combined normal WBC and CRP. CONCLUSION In IVT-treated patients, leukocytosis independently predicted poor functional outcome and death. Bleeding complications after IVT were not independently associated with leukocytosis
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