190 research outputs found
Proton-He elastic scattering at low energies
We present new accurate measurements of the differential cross section
and the proton analyzing power for proton-He
elastic scattering at various energies. A supersonic gas jet target has been
employed to obtain these low energy cross section measurements. The
distributions have been measured at = 0.99, 1.59,
2.24, 3.11, and 4.02 MeV. Full angular distributions of have been
measured at = 1.60, 2.25, 3.13, and 4.05 MeV. This set of
high-precision data is compared to four-body variational calculations employing
realistic nucleon-nucleon (NN) and three-nucleon (3N) interactions. For the
unpolarized cross section the agreement between the theoretical calculation and
data is good when a potential is used. The comparison between the
calculated and measured proton analyzing powers reveals discrepancies of
approximately 50% at the maximum of each distribution. This is analogous to the
existing `` Puzzle'' known for the past 20 years in nucleon-deuteron
elastic scattering.Comment: 22 pages, 9 figures, to be published in Physical Review C, corrected
reference 4
Benchmark calculation of n-3H and p-3He scattering
The n-3H and p-3He elastic phase-shifts below the trinucleon disintegration
thresholds are calculated by solving the 4-nucleon problem with three different
realistic nucleon-nucleon interactions (the I-N3LO model by Entem and
Machleidt, the Argonne v18 potential model, and a low-k model derived from the
CD-Bonn potential). Three different methods -- Alt, Grassberger and Sandhas,
Hyperspherical Harmonics, and Faddeev-Yakubovsky -- have been used and their
respective results are compared. For both n-3H and p-3He we observe a rather
good agreement between the three different theoretical methods. We also compare
the theoretical predictions with the available experimental data, confirming
the large underprediction of the p-3He analyzing power.Comment: 18 pages, 9 figure
The Ay Problem for p-3He Elastic Scattering
We present evidence that numerically accurate quantum calculations employing
modern internucleon forces do not reproduce the proton analyzing power, A_y,
for p-3He elastic scattering at low energies. These calculations underpredict
new measured analyzing powers by approximately 30% at E_{c.m.} = 1.20 MeV and
by 40% at E_{c.m.} = 1.69 MeV, an effect analogous to a well-known problem in
p-d and n-d scattering. The calculations are performed using the complex Kohn
variational principle and the (correlated) Hyperspherical Harmonics technique
with full treatment of the Coulomb force. The inclusion of the three-nucleon
interaction does not improve the agreement with the experimental data.Comment: Latex file, 4 pages, 2 figures, to be published on Phys. Rev. Let
Overview of prognostic systems for hepatocellular carcinoma and ITA.LI.CA external validation of MESH and CNLC classifications
Prognostic assessment in patients with HCC remains an extremely difficult clinical task due to the complexity of this cancer where tumour characteristics interact with degree of liver dysfunction, patient general health status, and a large span of available treatment options. Several prognostic systems have been proposed in the last three decades, both from the Asian and European/North American countries. Prognostic scores, such as the CLIP score and the recent MESH score, have been generated on a solid statistical basis from real life population data, while staging systems, such as the BCLC scheme and the recent CNLC classification, have been created by experts according to recent HCC prognostic evidences from the literature. A third category includes combined prognostic systems that can be used both as prognostic scores and staging systems. A recent example is the ITA.LI.CA prognostic system including either a prognostic score and a simplified staging system. This review focuses first on an overview of the main prognostic systems for HCC classified according to the above three categories, and, second, on a comprehensive description of the methodology required for a correct comparison between different systems in terms of prognostic performance. In this second section the main studies in the literature comparing different prognostic systems are described in detail. Lastly, a formal comparison between the last prognostic systems proposed for each of the above three categories is performed using a large Italian database including 6882 HCC patients in order to concretely apply the comparison rules previously described
Evaluation of Commercial Probiotic Products
Although there is a vast number of probiotic products commercially available due to their acceptability and increasing usage, their quality control has continuously been a major concern. This study aimed to assess some commercially available probiotics on the UK market for content in relation to their label claim. Seven products were used for the study. The bacteria content were isolated, identified and enumerated on selective media. The results revealed that all products evaluated contained viable probiotic bacteria but only three out of the seven products (43%) contained the claimed culture concentration or more. None of the multispecies product contained all the labelled probiotic bacteria. Misidentification of some species occurred. The results concurred with previous studies and showed that quality issues with commercial probiotics remain. Since probiotic activity is linked with probiotic concentration and is strain specific, the need exist for a global comprehensive legislation to control the quality of probiotics whose market is gaining huge momentum
Pain and Frailty in Hospitalized Older Adults
Introduction: Pain and frailty are prevalent conditions in the older population. Many chronic diseases are likely involved in their origin, and both have a negative impact on quality of life. However, few studies have analysed their association. Methods: In light of this knowledge gap, 3577 acutely hospitalized patients 65 years or older enrolled in the REPOSI register, an Italian network of internal medicine and geriatric hospital wards, were assessed to calculate the frailty index (FI). The impact of pain and some of its characteristics on the degree of frailty was evaluated using an ordinal logistic regression model after adjusting for age and gender. Results: The prevalence of pain was 24.7%, and among patients with pain, 42.9% was regarded as chronic pain. Chronic pain was associated with severe frailty (OR = 1.69, 95% CI 1.38–2.07). Somatic pain (OR = 1.59, 95% CI 1.23–2.07) and widespread pain (OR = 1.60, 95% CI 0.93–2.78) were associated with frailty. Osteoarthritis was the most common cause of chronic pain, diagnosed in 157 patients (33.5%). Polymyalgia, rheumatoid arthritis and other musculoskeletal diseases causing chronic pain were associated with a lower degree of frailty than osteoarthritis (OR = 0.49, 95%CI 0.28–0.85). Conclusions: Chronic and somatic pain negatively affect the degree of frailty. The duration and type of pain, as well as the underlying diseases associated with chronic pain, should be evaluated to improve the hospital management of frail older people
Understanding Factors Associated With Psychomotor Subtypes of Delirium in Older Inpatients With Dementia
The multifaceted spectrum of liver cirrhosis in older hospitalised patients: Analysis of the REPOSI registry
Background: Knowledge on the main clinical and prognostic characteristics of older multimorbid subjects with liver cirrhosis (LC) admitted to acute medical wards is scarce. Objectives: To estimate the prevalence of LC among older patients admitted to acute medical wards and to assess the main clinical characteristics of LC along with its association with major clinical outcomes and to explore the possibility that well-distinguished phenotypic profiles of LC have classificatory and prognostic properties. Methods: A cohort of 6,193 older subjects hospitalised between 2010 and 2018 and included in the REPOSI registry was analysed. Results: LC was diagnosed in 315 patients (5%). LC was associated with rehospitalisation (age-sex adjusted hazard ratio, [aHR] 1.44; 95% CI, 1.10-1.88) and with mortality after discharge, independently of all confounders (multiple aHR, 2.1; 95% CI, 1.37-3.22), but not with in-hospital mortality and incident disability. Three main clinical phenotypes of LC patients were recognised: relatively fit subjects (FIT, N = 150), subjects characterised by poor social support (PSS, N = 89) and, finally, subjects with disability and multimorbidity (D&M, N = 76). PSS subjects had an increased incident disability (35% vs 13%, P < 0.05) compared to FIT. D&M patients had a higher mortality (in-hospital: 12% vs 3%/1%, P < 0.01; post-discharge: 41% vs 12%/15%, P < 0.01) and less rehospitalisation (10% vs 32%/34%, P < 0.01) compared to PSS and FIT. Conclusions: LC has a relatively low prevalence in older hospitalised subjects but, when present, accounts for worse post-discharge outcomes. Phenotypic analysis unravelled the heterogeneity of LC older population and the association of selected phenotypes with different clinical and prognostic features
Evidence-based guidelines for use of probiotics in preterm neonates
<p>Abstract</p> <p>Background</p> <p>Current evidence indicates that probiotic supplementation significantly reduces all-cause mortality and definite necrotising enterocolitis without significant adverse effects in preterm neonates. As the debate about the pros and cons of routine probiotic supplementation continues, many institutions are satisfied with the current evidence and wish to use probiotics routinely. Because of the lack of detail on many practical aspects of probiotic supplementation, clinician-friendly guidelines are urgently needed to optimise use of probiotics in preterm neonates.</p> <p>Aim</p> <p>To develop evidence-based guidelines for probiotic supplementation in preterm neonates.</p> <p>Methods</p> <p>To develop core guidelines on use of probiotics, including strain selection, dose and duration of supplementation, we primarily used the data from our recent updated systematic review of randomised controlled trials. For equally important issues including strain identification, monitoring for adverse effects, product format, storage and transport, and regulatory hurdles, a comprehensive literature search, covering the period 1966-2010 without restriction on the study design, was conducted, using the databases PubMed and EMBASE, and the proceedings of scientific conferences; these data were used in our updated systematic review.</p> <p>Results</p> <p>In this review, we present guidelines, including level of evidence, for the practical aspects (for example, strain selection, dose, duration, clinical and laboratory surveillance) of probiotic supplementation, and for dealing with non-clinical but important issues (for example, regulatory requirements, product format). Evidence was inadequate in some areas, and these should be a target for further research.</p> <p>Conclusion</p> <p>We hope that these evidence-based guidelines will help to optimise the use of probiotics in preterm neonates. Continued research is essential to provide answers to the current gaps in knowledge about probiotics.</p
Factors affecting adherence to guidelines for antithrombotic therapy in elderly patients with atrial fibrillation admitted to internal medicine wards
Current guidelines for ischemic stroke prevention in atrial fibrillation or flutter (AFF) recommend Vitamin K antagonists (VKAs) for patients at high-intermediate risk and aspirin for those at intermediate-low risk. The cost-effectiveness of these treatments was demonstrated also in elderly patients. However, there are several reports that emphasize the underuse of pharmacological prophylaxis of cardio-embolism in patients with AFF in different health care settings.
AIMS: To evaluate the adherence to current guidelines on cardio-embolic prophylaxis in elderly (> 65 years old) patients admitted with an established diagnosis of AFF to the Italian internal medicine wards participating in REPOSI registry, a project on polypathologies/polytherapies stemming from the collaboration between the Italian Society of Internal Medicine and the Mario Negri Institute of Pharmacological Research; to investigate whether or not hospitalization had an impact on guidelines adherence; to test the role of possible modifiers of VKAs prescription.
METHODS: We retrospectively analyzed registry data collected from January to December 2008 and assessed the prevalence of patients with AFF at admission and the prevalence of risk factors for cardio-embolism. After stratifying the patients according to their CHADS(2) score the percentage of appropriateness of antithrombotic therapy prescription was evaluated both at admission and at discharge. Univariable and multivariable logistic regression models were employed to verify whether or not socio-demographic (age >80years, living alone) and clinical features (previous or recent bleeding, cranio-facial trauma, cancer, dementia) modified the frequency and modalities of antithrombotic drugs prescription at admission and discharge.
RESULTS: Among the 1332 REPOSI patients, 247 were admitted with AFF. At admission, CHADS(2) score was ≥ 2 in 68.4% of patients, at discharge in 75.9%. Among patients with AFF 26.5% at admission and 32.8% at discharge were not on any antithrombotic therapy, and 43.7% at admission and 40.9% at discharge were not taking an appropriate therapy according to the CHADS(2) score. The higher the level of cardio-embolic risk the higher was the percentage of antiplatelet- but not of VKAs-treated patients. At admission or at discharge, both at univariable and at multivariable logistic regression, only an age >80 years and a diagnosis of cancer, previous or active, had a statistically significant negative effect on VKAs prescription. Moreover, only a positive history of bleeding events (past or present) was independently associated to no VKA prescription at discharge in patients who were on VKA therapy at admission. If heparin was considered as an appropriate therapy for patients with indication for VKAs, the percentage of patients admitted or discharged on appropriate therapy became respectively 43.7% and 53.4%.
CONCLUSION: Among elderly patients admitted with a diagnosis of AFF to internal medicine wards, an appropriate antithrombotic prophylaxis was taken by less than 50%, with an underuse of VKAs prescription independently of the level of cardio-embolic risk. Hospitalization did not improve the adherence to guideline
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