318 research outputs found
New Perspective in HCV Clinical and Economical Management of the Current and Future Therapies
Hepatitis C virus (HCV) is a progressive disease that infects more than 185 million individuals worldwide and is associated with persistence of viral replication and ongoing necroinflammation and fibrosis. To date 20% of patients chronically infected with HCV progress to cirrhosis. Epidemiological studies demonstrate that the incidence of HCV is not well known, because acute infection is generally asymptomatic. The global prevalence is about 2.2% and there is a large degree of geographic variability. Before the 2011, the gold standard of therapy for the treatment of chronic hepatitis C (CHC) was based on the combination of pegylated Interferon (peg-IFN) and Ribavirin (RBV). However, several aspects related to safety profile limited their use in clinical practice. In the recent years, thanks to basic research on HCV structure and replicative cycle, it has been possible to develop direct acting antiviral drugs that have dramatically increased the viral clearance rate. Specifically, the advent of the triple therapy employing direct acting antivirals has dramatically increased the viral clearance rate, from less than 10%, with the initial regimen of IFN monotherapy, to more than 95% with the current therapy. Even though new medications for hepatitis C are effective disease modifiers and have the potential, in a long term perspective, to eradicate the pathology, the cost of new treatments are unlikely to be sustainable for the NHSs. The evidence documenting the effectiveness and tolerability of the new therapies for HCV and several pharmacoeconomic analysis, shows that despite the cost, the new treatments can be considered cost-effective in the long period. However, the health care systems are unable to compensate the height financial resources immediately needed for treating patients with the long terms savings that will be obtained from the eradication of HCV. Indeed, new pharmaceutical policy and a global commitment is required to improve strategies of treatment and price negotiation with pharmaceutical companies to move from a theoretical cost-effectiveness approach to a practical cost-sustainable reality
Combined specular and off-specular reflectometry: elucidating the complex structure of soft buried interfaces
Neutron specular reflectometry (SR) and off-specular scattering (OSS) are non\uaddestructive techniques which, through deuteration, give a high contrast even among chemically identical species and are therefore highly suitable for investigations of soft-matter thin films. Through a combination of these two techniques, the former yielding a density profile in the direction normal to the sample surface and the latter yielding a depth-resolved in-plane lateral structure, one can obtain quite detailed information on buried morphology on length scales ranging from the order of \ue5ngstr\uf6ms to ∼10 \ub5m. This is illustrated via quantitative evaluation of data on SR and OSS collected in time-of-flight (ToF) measurements of a set of films composed of immiscible polymer layers, protonated poly(methyl methacrylate) and deuterated polystyrene, undergoing a decomposition process upon annealing. Joint SR and OSS data analysis was performed by the use of a quick and robust originally developed algorithm including a common absolute-scale normalization of both types of scattering, which are intricately linked, constraining the model to a high degree. This, particularly, makes it possible to distinguish readily between different dewetting scenarios driven either by the nucleation and growth of defects (holes, protrusions etc.) or by thermal fluctuations in the buried interface between layers. Finally, the 2D OSS maps of particular cases are presented in different spaces and qualitative differences are explained, allowing also the qualitative differentiation of the in-plane structure of long-range order, the correlated roughness and bulk defects by a simple inspection of the scattering maps prior to quantitative fit
A symmetric polymer blend confined into a film with antisymmetric surfaces: interplay between wetting behavior and phase diagram
We study the phase behavior of a symmetric binary polymer blend which is
confined into a thin film. The film surfaces interact with the monomers via
short range potentials. We calculate the phase behavior within the
self-consistent field theory of Gaussian chains. Over a wide range of
parameters we find strong first order wetting transitions for the semi-infinite
system, and the interplay between the wetting/prewetting behavior and the phase
diagram in confined geometry is investigated. Antisymmetric boundaries, where
one surface attracts the A component with the same strength than the opposite
surface attracts the B component, are applied. The phase transition does not
occur close to the bulk critical temperature but in the vicinity of the wetting
transition. For very thin films or weak surface fields one finds a single
critical point at . For thicker films or stronger surface fields
the phase diagram exhibits two critical points and two concomitant coexistence
regions. Only below a triple point there is a single two phase coexistence
region. When we increase the film thickness the two coexistence regions become
the prewetting lines of the semi-infinite system, while the triple temperature
converges towards the wetting transition temperature from above. The behavior
close to the tricritical point, which separates phase diagrams with one and two
critical points, is studied in the framework of a Ginzburg-Landau ansatz.
Two-dimensional profiles of the interface between the laterally coexisting
phases are calculated, and the interfacial and line tensions analyzed. The
effect of fluctuations and corrections to the self-consistent field theory are
discussed.Comment: Phys.Rev.E in prin
TM6SF2 rs58542926 is not associated with steatosis and fibrosis in largecohort of patients with genotype 1 chronic hepatitis C
Background & Aims: We tested the putative association of the rs58542926 variant of TM6SF2, a recently described genetic determinant of nonalcoholic fatty liver disease, with steatosis and fibrosis in genotype 1(G1) chronic hepatitis C(CHC) patients. Methods: A total of 694 consecutively biopsied Caucasian G1 CHC patients were genotyped for TM6SF2 rs58542926, IL28B rs12979860 and PNPLA3 rs738409. Steatosis was classified as absent (<5%), mild-moderate(5-29%) and severe( 6530%), Fibrosis was considered severe if=F3-F4. Results: Carriers of TM6SF2 rs58542926 (6.3% of patients) exhibited lower serum levels of cholesterol (P=0.04) and triglycerides (P=0.01), but a similar distribution of steatosis severity (P=0.63), compared to noncarriers. Prevalence and severity of steatosis were reduced in IL28B C allele carriers (P=0.005) and elevated in PNPLA3G allele carriers (P<0.001). After adjustment for age, gender, body mass index and homoeostasis model assessment score, steatosis severity was independently associated with IL28B rs12979860 (odds ratio [OR] 0.69, 95% confidence interval [CI] 0.55-0.86, P=0.001) and PNPLA3 rs738409 (OR 1.84, 95% CI 1.46-2.83, P<0.001), but not TM6SF2 rs58542926 (OR 1.48, 95% CI 0.82-2.69, P=0.19). Variants of TM6SF2 (30.9% vs. 25%, P=0.40), IL28B and PNPLA3 were not directly associated with fibrosis severity, although variants of IL28B and PNPLA3 promoted steatosis (OR 1.36, 95% CI 1.06-1.75, P=0.01) that in turn is associated with severe fibrosis. Conclusions: In G1 CHC patients, TM6SF2 rs58542926 does not affect the histological severity of liver damage. However, IL28B rs12979860 and PNPLA3 rs738409 modify steatosis
Interface localisation-delocalisation transition in a symmetric polymer blend: a finite-size scaling Monte Carlo study
Using extensive Monte Carlo simulations we study the phase diagram of a
symmetric binary (AB) polymer blend confined into a thin film as a function of
the film thickness D. The monomer-wall interactions are short ranged and
antisymmetric, i.e, the left wall attracts the A-component of the mixture with
the same strength as the right wall the B-component, and give rise to a first
order wetting transition in a semi-infinite geometry. The phase diagram and the
crossover between different critical behaviors is explored. For large film
thicknesses we find a first order interface localisation/delocalisation
transition and the phase diagram comprises two critical points, which are the
finite film width analogies of the prewetting critical point. Using finite size
scaling techniques we locate these critical points and present evidence of 2D
Ising critical behavior. When we reduce the film width the two critical points
approach the symmetry axis of the phase diagram and for we encounter a tricritical point. For even smaller film thickness the
interface localisation/delocalisation transition is second order and we find a
single critical point at .
Measuring the probability distribution of the interface position we determine
the effective interaction between the wall and the interface. This effective
interface potential depends on the lateral system size even away from the
critical points. Its system size dependence stems from the large but finite
correlation length of capillary waves. This finding gives direct evidence for a
renormalization of the interface potential by capillary waves in the framework
of a microscopic model.Comment: Phys.Rev.
Molecular subtypes, metastatic pattern and patient age in breast cancer: An analysis of italian network of cancer registries (airtum) data
Breast cancer stage at diagnosis, patient age and molecular tumor subtype influence disease progression. The aim of this study was to analyze the relationships between these factors and survival in breast cancer patients among the Italian population using data from the AIRTUM national database. We enrolled women with primary breast cancer from 17 population‐based cancer registries. Patients were subdivided into older (>69 years), middle (50–69 years) and younger age groups (<50 years) and their primary tumors categorized into four molecular subtypes based on hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status. There were 8831 patients diagnosed between 2010 and 2012 included. The most represented age group was 50– 69 years (41.7%). In 5735 cases the molecular subtype was identified: HER2–/HR+ was the most frequent (66.2%) and HER2+/HR− the least (6.2%). Of the 390 women with metastases at diagnosis, 38% had simultaneous involvement of multiple sites, independent of age and molecular profile. In women with a single metastatic site, bone (20% of cases), liver (11%), lung (7%) and brain (3%) were the most frequent. In the studied age groups with different receptor expression profiles, the tumor metastasized to target organs with differing frequencies, affecting survival. Five‐year survival was lowest in women with triple‐negative (HER2−/HR–) tumors and women with brain metastases at diagnosis
Intrinsic profiles and capillary waves at homopolymer interfaces: a Monte Carlo study
A popular concept which describes the structure of polymer interfaces by
``intrinsic profiles'' centered around a two dimensional surface, the ``local
interface position'', is tested by extensive Monte Carlo simulations of
interfaces between demixed homopolymer phases in symmetric binary (AB)
homopolymer blends, using the bond fluctuation model. The simulations are done
in an LxLxD geometry. The interface is forced to run parallel to the LxL planes
by imposing periodic boundary conditions in these directions and fixed boundary
conditions in the D direction, with one side favoring A and the other side
favoring B. Intrinsic profiles are calculated as a function of the ``coarse
graining length'' B by splitting the system into columns of size BxBxD and
averaging in each column over profiles relative to the local interface
position. The results are compared to predictions of the self-consistent field
theory. It is shown that the coarse graining length can be chosen such that the
interfacial width matches that of the self-consistent field profiles, and that
for this choice of B the ``intrinsic'' profiles compare well with the
theoretical predictions.Comment: to appear in Phys. Rev.
Variation of electric shielding on virtual Frisch-grid detectors
Because of the low mobility of holes, CdZnTe (CZT) detectors operate as electron-transport-only type devices whose particular geometrical parameters and contacts configurations are specially chosen to minimize the contribution of uncollected holes into the output signal amplitudes (induction effect). Several detector configurations have been proposed to address this problem. One of them employs a large geometrical aspect ratio, parallelepiped-shaped crystal with two planar contacts on the top and bottom surfaces (anode and cathode) and an additional shielding electrode placed on a crystal\u27s side to create the virtual Frisch-grid effect. We studied the effect of the shielding electrode length, as well as its location, on the responses of 6 x 6 x 15 mm(3) virtual Frisch-grid detectors. We found that the length of the shielding electrode placed next to the anode can be reduced to 5 mm with no adverse effects on the device performance. Meanwhile, this allows for charge loss correction by reading the cathode signal
Potentially harmful effects of inspiratory synchronization during pressure preset ventilation
Purpose: Pressure preset ventilation (PPV) modes with set inspiratory time can be classified according to their ability to synchronize pressure delivery with patient's inspiratory efforts (i-synchronization). Non-i-synchronized (like airway pressure release ventilation, APRV), partially i-synchronized (like biphasic airway pressure), and fully i-synchronized modes (like assist-pressure control) can be distinguished. Under identical ventilatory settings across PPV modes, the degree of i-synchronization may affect tidal volume (V T), transpulmonary pressure (P TP), and their variability. We performed bench and clinical studies. Methods: In the bench study, all the PPV modes of five ventilators were tested with an active lung simulator. Spontaneous efforts of −10cmH2O at rates of 20 and 30breaths/min were simulated. Ventilator settings were high pressure 30cmH2O, positive end-expiratory pressure (PEEP) 15cmH2O, frequency 15breaths/min, and inspiratory to expiratory ratios (I:E) 1:3 and 3:1. In the clinical studies, data from eight intubated patients suffering from acute respiratory distress syndrome (ARDS) and ventilated with APRV were compared to the bench tests. In four additional ARDS patients, each of the PPV modes was compared. Results: As the degree of i-synchronization among the different PPV modes increased, mean V T and P TP swings markedly increased while breathing variability decreased. This was consistent with clinical comparison in four ARDS patients. Observational results in eight ARDS patients show low V T and a high variability with APRV. Conclusion: Despite identical ventilator settings, the different PPV modes lead to substantial differences in V T, P TP, and breathing variability in the presence spontaneous efforts. Clinicians should be aware of the possible harmful effects of i-synchronization especially when high V T is undesirabl
Advancement of photospheric radius expansion and clocked type-I x-ray burst models with the new 22Mg(α,p)25 Al reaction rate determined at Gamow energy
We report the first (in)elastic scattering measurement of
with the capability to select and measure in a broad
energy range the proton resonances in Si contributing to the
Mg reaction at type I x-ray burst energies. We measured
spin-parities of four resonances above the threshold of Si that
are found to strongly impact the Mg rate. The new rate
advances a state-of-the-art model to remarkably reproduce light curves of the
GS 182624 clocked burster with mean deviation % and permits us to
discover a strong correlation between the He abundance in the accreting
envelope of photospheric radius expansion burster and the dominance of
Mg branch.Comment: accepted by Physical Review Letters on 5 August 2021, published 19
October 202
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