Exploring differential item functioning in the SF-36 by demographic, clinical, psychological and social factors in an osteoarthritis population

The SF-36 is a very commonly used generic measure of health outcome in osteoarthritis (OA). An important, but frequently overlooked, aspect of validating health outcome measures is to establish if items work in the same way across subgroup of a population. That is, if respondents have the same 'true' level of outcome, does the item give the same score in different subgroups or is it biased towards one subgroup or another. Differential item functioning (DIF) can identify items that may be biased for one group or another and has been applied to measuring patient reported outcomes. Items may show DIF for different conditions and between cultures, however the SF-36 has not been specifically examined in an osteoarthritis population nor in a UK population. Hence, the aim of the study was to apply the DIF method to the SF-36 for a UK OA population. The sample comprised a community sample of 763 people with OA who participated in the Somerset and Avon Survey of Health. The SF-36 was explored for DIF with respect to demographic, social, clinical and psychological factors. Well developed ordinal regression models were used to identify DIF items. Results: DIF items were found by age (6 items), employment status (6 items), social class (2 items), mood (2 items), hip v knee (2 items), social deprivation (1 item) and body mass index (1 item). Although the impact of the DIF items rarely had a significant effect on the conclusions of group comparisons, in most cases there was a significant change in effect size. Overall, the SF-36 performed well with only a small number of DIF items identified, a reassuring finding in view of the frequent use of the SF-36 in OA. Nevertheless, where DIF items were identified it would be advisable to analyse data taking account of DIF items, especially when age effects are the focus of interest

Distributed Leadership Agency and Work Outcomes: Validation of the Italian DLA and Its Relations With Commitment, Trust, and Satisfaction

Forms of collective leadership, such as distributed leadership, have become increasingly important. The need for measurement of the variables involved in the delegation processes represents a new challenge for organizations that want to ensure high-level working. The present study aimed to validate the Italian version of the distributed leadership agency (DLA). The study was carried out on 704 employees (doctors, nurses, clerks, staff workers, healthcare assistants, consultants, management) of an Italian public hospital, who were selected to complete a survey on organizational perceptions. Multiple confirmatory factor analyses (maximum likelihood) have been computed to explore the factorial structure of the DLA, along with associations with other work outcomes. Results about the Italian DLA confirmed the original trifactorial structure of the construct, suggested by Yukl (2002), through good fit indexes and reliability scores; moreover, consistent with the literature, DLA was strongly related to satisfaction, commitment, and trust. Results contribute to underline the robustness of the construct of DLA in different cultural sectors and provide a useful tool to be adopted in the Italian context

Resistin, visfatin, leptin and omentin are differently related to hormonal and metabolic parameters in growth hormone-deficient children

PURPOSE: The effect of growth hormone (GH) on adipose tissue and the role of adipokines in modulating metabolism are documented, but with discordant data. Our aim was to evaluate the impact of GH treatment on a series of selected adipokines known to have a metabolic role and poorly investigated in this setting. METHODS: This is a prospective study. Thirty-one prepubertal children (25 M, 6 F; aged 8.5 ± 1.6 years) with isolated GH deficiency treated with GH for at least 12 months and 30 matched controls were evaluated. Auxological and metabolic parameters, insulin sensitivity indexes, leptin, soluble leptin receptor, adiponectin, visfatin, resistin, omentin, adipocyte fatty acid-binding protein and retinol-binding protein-4 were evaluated before and after 12 months of treatment. RESULTS: At baseline, no significant difference in metabolic parameters was found between GHD children and controls, except for higher LDL cholesterol (p = 0.004) in the first group. At multivariate analysis, LDL cholesterol was independently associated with resistin (B 0.531; p = 0.002), while IGF-I was the only variable independently associated with visfatin (B 0.688; p < 0.001). After 12 months, a significant increase in fasting insulin (p = 0.008), Homa-IR (p = 0.007) and visfatin (p < 0.001) was found, with a concomitant decrease in LDL cholesterol (p = 0.015), QUICKI (p = 0.001), ISI Matsuda (p = 0.006), leptin (p = 0.015) and omentin (p = 0.003)]. At multivariate analysis, BMI was the only variable independently associated with leptin (B 0.485; p = 0.040). CONCLUSIONS: GH treatment modifies adipokine secretion and the perturbation of some adipokine levels could contribute to the clinical and metabolic changes observed during the follow-up

ADIPONECTIN, LEPTIN, RESISTIN LEVELS IN CYSTIC FIBROSIS ADOLESCENTS

INTRODUCTION: Patients with Cystic Fibrosis, especially in adolescence, could develop endocrine and metabolic complications, related to nutritional state and chronic inflammation. They develop a progressive decrease in lean body mass correlated with the progression of lung disease. Adipose tissue is involved as well and adipocytokines are a possible link between malnutrition and long term complications. PATIENTS AND METHODS: In 24 Cystic Fibrosis adolescents we studied auxological, nutritional, glycometabolic, endocrine patterns, together with leptin, adiponectin and resistin levels. We selected patients not affected by diabetes, insulin resistance, malnutrition, acute inflammatory states so as to avoid possible influences on the adipocytokines. RESULTS: All patients presented with an adequate BMI centile, with no statistically significant difference versus controls. HOMA IR and HOMA B% are in the normal range but lower than in controls, expression of a lower insulin-resistance with a lower insulin secretion. Leptin is significantly higher than in controls and maintains a correlation with BMI and gender. Resistin levels are more elevated in Cystic Fibrosis than in controls, with a statistically significant direct correlation with CRP (C-reactive protein) and insulinemia T0\u2019 and T120\u2019.Adiponectin is significantly higher in Cystic Fibrosis, inversely correlated with CRP and insulinemia and directly with cholesterol and HDL-cholesterol. CONCLUSIONS:The detection of adipocytokines levels could improve the metabolic follow-up of these patients: the maintenance of an adequate leptin gender difference is useful in the follow-up of puberty in adolescence. Adiponectin could be a marker of insulin sensitivity and prevent protein catabolism and loss of lean body mass. Resistin levels may be used as a marker of insulin resistance and may indicate the severity of chronic inflammation. This is the first study available in literature about adiponectin levels in pediatric Cystic Fibrosis patients and about resistin in Cystic Fibrosis

Effects of Atmospheric CO2 Level on the Metabolic Response of Resistant and Susceptible Wheat to Fusarium graminearum Infection.

Rising atmospheric CO2 concentrations and associated climate changes are thought to have contributed to the steady increase of Fusarium head blight (FHB) on wheat. However, our understanding of precisely how elevated CO2 influences the defense response of wheat against Fusarium graminearum remains limited. In this study, we evaluated the metabolic profiles of susceptible (Norm) and moderately resistant (Alsen) spring wheat in response to whole-head inoculation with two deoxynivalenol (DON)-producing F. graminearum isolates (DON+), isolates 9F1 and Gz3639, and a DON-deficient (DON−) isolate (Gzt40) at ambient (400 ppm) and elevated (800 ppm) CO2 concentrations. The effects of elevated CO2 were dependent on both the Fusarium strain and the wheat variety, but metabolic differences in the host can explain the observed changes in F. graminearum biomass and DON accumulation. The complexity of abiotic and biotic stress interactions makes it difficult to determine if the observed metabolic changes in wheat are a result of CO2-induced changes in the host, the pathogen, or a combination of both. However, the effects of elevated CO2 were not dependent on DON production. Finally, we identified several metabolic biomarkers for wheat that can reliably predict FHB resistance or susceptibility, even as atmospheric CO2 levels rise

Left atrial trajectory impairment in hypertrophic cardiomyopathy disclosed by geometric morphometrics and parallel transport

The analysis of full Left Atrium (LA) deformation and whole LA deformational trajectory in time has been poorly investigated and, to the best of our knowledge, seldom discussed in patients with Hypertrophic Cardiomyopathy. Therefore, we considered 22 patients with Hypertrophic Cardiomyopathy (HCM) and 46 healthy subjects, investigated them by three-dimensional Speckle Tracking Echocardiography, and studied the derived landmark clouds via Geometric Morphometrics with Parallel Transport. Trajectory shape and trajectory size were different in Controls versus HCM and their classification powers had high AUC (Area Under the Receiving Operator Characteristic Curve) and accuracy. The two trajectories were much different at the transition between LA conduit and booster pump functions. Full shape and deformation analyses with trajectory analysis enabled a straightforward perception of pathophysiological consequences of HCM condition on LA functioning. It might be worthwhile to apply these techniques to look for novel pathophysiological approaches that may better define atrio-ventricular interaction

Significance of borderline hemoglobin A2 values in an Italian population with a high prevalence of -thalassemia

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Resonant enhancement in leptogenesis

Vanilla leptogenesis within the type I seesaw framework requires the mass scale of the right-handed neutrinos to be above 109 GeV. This lower bound can be avoided if at least two of the sterile states are almost mass degenerate, which leads to an enhancement of the decay asymmetry. Leptogenesis models that can be tested in current and upcoming experiments often rely on this resonant enhancement, and a systematic and consistent description is therefore necessary for phenomenological applications. In this review article, we give an overview of different methods that have been used to study the saturation of the resonant enhancement when the mass difference becomes comparable to the characteristic width of the Majorana neutrinos. In this limit, coherent flavor transitions start to play a decisive role, and off-diagonal correlations in flavor space have to be taken into account. We compare various formalisms that have been used to describe the resonant regime and discuss under which circumstances the resonant enhancement can be captured by simplified expressions for the CP asymmetry. Finally, we briefly review some of the phenomenological aspects of resonant leptogenesis

ARS leptogenesis

We review the current status of the leptogenesis scenario originally proposed by Akhmedov, Rubakov and Smirnov (ARS). It takes place in the parametric regime where the right-handed neutrinos are at the electroweak scale or below and the CP-violating effects are induced by the coherent superposition of different right-handed mass eigenstates. Two main theoretical approaches to derive quantum kinetic equations, the Hamiltonian time evolution as well as the Closed-Time-Path technique are presented, and we discuss their relations. For scenarios with two right-handed neutrinos, we chart the viable parameter space. Both, a Bayesian analysis, that determines the most likely configurations for viable leptogenesis given different variants of flat priors, and a determination of the maximally allowed mixing between the light, mostly left-handed, and heavy, mostly right-handed, neutrino states are discussed. Rephasing invariants are shown to be a useful tool to classify and to understand various distinct contributions to ARS leptogenesis that can dominate in different parametric regimes. While these analyses are carried out for the parametric regime where initial asymmetries are generated predominantly from lepton-number conserving, but flavor violating effects, we also review the contributions from lepton-number violating operators and identify the regions of parameter space where these are relevant.Fil: Drewes, Alejandro Marcelo. Technische Universitat München; AlemaniaFil: Garbrecht, B.. Technische Universitat München; AlemaniaFil: Hernández, P.. Universidad de Valencia; España. Cern - European Organization For Nuclear Research; Suiza. Université Catholique de Louvain. Particle Physics and Phenomenology. Centre for Cosmology; SuizaFil: Kekic, M.. Universidad de Valencia; EspañaFil: Lopez-Pavon, J.. Cern - European Organization For Nuclear Research; SuizaFil: Racker, Juan Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Rius, Natalia. Universidad de Valencia; EspañaFil: Salvado, J.. Universidad de Valencia; EspañaFil: Teresi, D.. Université Libre de Bruxelles; Bélgic