764 research outputs found
A model for the compressible, viscoelastic behavior of human amnion addressing tissue variability through a single parameter
A viscoelastic, compressible model is proposed to rationalize the recently reported response of human amnion in multiaxial relaxation and creep experiments. The theory includes two viscoelastic contributions responsible for the short- and long-term time- dependent response of the material. These two contributions can be related to physical processes: water flow through the tissue and dissipative characteristics of the collagen fibers, respectively. An accurate agreement of the model with the mean tension and kinematic response of amnion in uniaxial relaxation tests was achieved. By variation of a single linear factor that accounts for the variability among tissue samples, the model provides very sound predictions not only of the uniaxial relaxation but also of the uniaxial creep and strip-biaxial relaxation behavior of individual samples. This suggests that a wide range of viscoelastic behaviors due to patient-specific variations in tissue composition
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Register-based cumulative prevalence of Autism Spectrum Disorders during childhood and adolescence in Central Italy
Background: Studies have evaluated the prevalence of Autism Spectrum Disorders (ASD), focusing on different ages during childhood and adolescence. How cumulative prevalence increases before adulthood remains unclear.
Methods: We used data from the Autism Register of the Regional Reference Centre for Autism in L'Aquila, Central Italy, to retrieve information on individuals born in 2001-2012 with any of the inclusion diagnoses of ASD (DSM criteria) for the period 2001 to 2018. Cumulative prevalence on L'Aquila district population data was calculated as percentages for three-year age strata.
Results: All prevalence data were estimated at December 31st, 2018. The overall crude prevalence was 0.95% (352 cases over 36938 population). Cumulative prevalence was 1.19% among those born in 2001-2003 (15 to 17 years of follow up), 1.15% among those born in 2004-2006 (12 to 14 years of follow up), 1.04% among those born in 2007-2009 (9 to 11 years of follow up), 0.80% among those born in 2010-2012 (6 to 8 years of follow up), and 0.57% among those born in 2013-2015 (3 to 5 years of follow up). The proportion of ASD diagnoses until the age of 5 years, compared to the group diagnosed 6 to 8 years of age, showed a significant increasing trend over calendar time (53.6% for those born in 2001-2003, to 77.0% for those born in 2010-2012).
Conclusions: Cumulative prevalence by time period provides a better understanding of ASD occurrence than a point prevalence. We did not find any difference in frequency of diagnosis comparing age strata and year of birth, suggesting that frequencies of ASD diagnosis remained roughly constant from 2001 to 2015. Results show that cumulative prevalence of autism diagnosis does not substantially change over time; instead, diagnosis of ASD is more likely at earliest ages over time, although new cases of ASD are also detected at later ages
Improving the uptake of preconception care and periconceptional folate supplementation: what do women think?
<p>Abstract</p> <p>Background</p> <p>Despite strong evidence of the benefits of preconception interventions to improve pregnancy outcomes, the delivery and uptake of preconception care in general and periconceptional folate supplementation in particular remains low. The aim of this study was to determine women's views of the barriers and enablers to the uptake of preconception care and periconceptional folate supplementation.</p> <p>Methods</p> <p>Focus groups were undertaken in 2007 with 17 women of reproductive age (18-45 years). To identify key issues and themes within the data, focus groups were analysed using an inductive process of thematic analysis.</p> <p>Results</p> <p>Most women were unaware of the need to attend for preconception care and were surprised at the breadth of issues involved. Women also felt general practitioners (GPs) should be more proactive in promoting preconception care availability but acknowledged that they themselves had to be thinking about pregnancy or becoming pregnant to be receptive to it. Barriers to periconceptional folate supplementation included confusion about reasons for use, dose, duration, timing and efficacy of folate use. Enablers included the desire to do anything they could to ensure optimum pregnancy outcomes, and promotional material and letters of invitation from their GP to advise them of the availability and the need for preconception care.</p> <p>Conclusion</p> <p>A number of important barriers and enablers exist for women regarding the delivery and uptake of preconception care and periconceptional folate supplementation. It is essential that these patient perspectives are addressed in both the implementation of evidence based clinical practice guidelines and in the systematic design of an intervention to improve preconception care delivery.</p
Serum Uric Acid and Kidney Disease Measures Independently Predict Cardiovascular and Total Mortality: The Uric Acid Right for Heart Health (URRAH) Project
Background: Serum uric acid predicts the onset and progression of kidney disease, and the occurrence of cardiovascular and all-cause mortality. Nevertheless, it is unclear which is the appropriate definition of hyperuricemia in presence of chronic kidney disease (CKD). Our goal was to study the independent impact of uric acid and CKD on mortality. Methods: We retrospectively investigated 21,963 patients from the URRAH study database. Hyperuricemia was defined on the basis of outcome specific cut-offs separately identified by ROC curves according to eGFR strata. The primary endpoints were cardiovascular and all-cause mortality. Results: After a mean follow-up of 9.8 year, there were 1,582 (7.20%) cardiovascular events and 3,130 (14.25%) deaths for all causes. The incidence of cardiovascular and all-cause mortality increased in parallel with reduction of eGFR strata and with progressively higher uric acid quartiles. During 215,618 person-years of follow-up, the incidence rate for cardiovascular mortality, stratified based on eGFR (>90, between 60 and 90 and <60 ml/min) was significantly higher in patients with hyperuricemia and albuminuria (3.8, 22.1 and 19.1, respectively) as compared to those with only one risk factor or none (0.4, 2.8 and 3.1, respectively). Serum uric acid and eGFR significantly interact in determining cardiovascular and all-cause mortality. For each SUA increase of 1 mg/dl the risk for mortality increased by 10% even after adjustment for potential confounding factors included eGFR and the presence of albuminuria. Conclusions: hyperuricemia is a risk factor for cardiovascular and all-cause mortality additively to eGFR strata and albuminuria, in patients at cardiovascular risk
Comparação do percentual de gordura obtido por bioimpedância, ultrassom e dobras cutâneas em adultos jovens
Association of uric acid with kidney function and albuminuria: the Uric Acid Right for heArt Health (URRAH) Project
Background: Hyperuricemia is commonly observed in patients with chronic kidney disease (CKD). However, a better understanding of the relationship among uric acid (UA) values, glomerular filtration rate (GFR) and albuminuria may shed light on the mechanisms underlying the excess of cardiovascular mortality associated with both chronic kidney disease and hyperuricemia and lead to better risk stratification. Our main goal was to study the relationships between serum uric acid and kidney disease measures (namely estimated GFR [eGFR] and albuminuria) in a large cohort of individuals at cardiovascular risk from the URic acid Right for heArt Health (URRAH) Project database.
Methods: Clinical data of 26,971 individuals were analyzed. Factors associated with the presence of hyperuricemia defined on the basis of previously determined URRAH cutoffs for cardiovascular and all-cause mortality were evaluated through multivariate analysis. Chronic kidney disease was defined as eGFR < 60 ml/min per 1.73 m2 and/or abnormal urinary albumin excretion diagnosed as: (i) microalbuminuria if urinary albumin concentration was > 30 and ≤ 300 mg/L, or if urinary albumin-to-creatinine ratio (ACR) was > 3.4 mg/mmol and ≤ 34 mg/mmol; (ii) macroalbuminuria if urinary albumin concentration was > 300 mg/L, or if ACR was > 34 mg/mmol.
Results: Mean age was 58 ± 15 years (51% males, 62% with hypertension and 12% with diabetes), mean eGFR was 81 ml/min per 1.73m22with a prevalence of eGFR < 60 and micro- or macroalbuminuria of 16, 15 and 4%, respectively. Serum uric acid showed a trend towards higher values along with decreasing renal function. Both the prevalence of gout and the frequency of allopurinol use increased significantly with the reduction of eGFR and the increase in albuminuria. Hyperuricemia was independently related to male gender, eGFR strata, and signs of insulin resistance such as body mass index (BMI) and triglycerides.
Conclusions: The lower the eGFR the higher the prevalence of hyperuricemia and gout. In subjects with eGFR < 60 ml/min the occurrence of hyperuricemia is about 10 times higher than in those with eGFR > 90 ml/min. The percentage of individuals treated with allopurinol was below 2% when GFR was above 60 ml/min, it increased to 20% in the presence of CKD 3b and rose further to 35% in individuals with macroalbuminuria
Serum Uric Acid/Serum Creatinine Ratio and Cardiovascular Mortality in Diabetic Individuals—The Uric Acid Right for Heart Health (URRAH) Project
Several studies have detected a direct association between serum uric acid (SUA) and
cardiovascular (CV) risk. In consideration that SUA largely depends on kidney function, some studies
explored the role of the serum creatinine (sCr)-normalized SUA (SUA/sCr) ratio in different settings.
Previously, the URRAH (URic acid Right for heArt Health) Study has identified a cut-off value of this
index to predict CV mortality at 5.35 Units. Therefore, given that no SUA/sCr ratio threshold for CV
risk has been identified for patients with diabetes, we aimed to assess the relationship between this
index and CV mortality and to validate this threshold in the URRAH subpopulation with diabetes; the
URRAH participants with diabetes were studied (n = 2230). The risk of CV mortality was evaluated by
the Kaplan–Meier estimator and Cox multivariate analysis. During a median follow-up of 9.2 years,
380 CV deaths occurred. A non-linear inverse association between baseline SUA/sCr ratio and risk
of CV mortality was detected. In the whole sample, SUA/sCr ratio > 5.35 Units was not a significant
predictor of CV mortality in diabetic patients. However, after stratification by kidney function,
values > 5.35 Units were associated with a significantly higher mortality rate only in normal kidney
function, while, in participants with overt kidney dysfunction, values of SUA/sCr ratio > 7.50 Units
were associated with higher CV mortality. The SUA/sCr ratio threshold, previously proposed by
the URRAH Study Group, is predictive of an increased risk of CV mortality in people with diabetes
and preserved kidney function. While, in consideration of the strong association among kidney
function, SUA, and CV mortality, a different cut-point was detected for diabetics with impaired
kidney function. These data highlight the different predictive roles of SUA (and its interaction with
kidney function) in CV risk, pointing out the difference in metabolic- and kidney-dependent SUA
levels also in diabetic individual
Prognostic Value and Relative Cutoffs of Triglycerides Predicting Cardiovascular Outcome in a Large Regional-Based Italian Database
BACKGROUND: Despite longstanding epidemiologic data on the association between increased serum triglycerides and cardiovascular events, the exact level at which risk begins to rise is unclear. The Working Group on Uric Acid and Cardiovascular
Risk of the Italian Society of Hypertension has conceived a protocol aimed at searching for the prognostic cutoff value of
triglycerides in predicting cardiovascular events in a large regional-based Italian cohort.
METHODS AND RESULTS: Among 14189 subjects aged 18 to 95years followed-up for 11.2 (5.3–13.2) years, the prognostic cutoff
value of triglycerides, able to discriminate combined cardiovascular events, was identified by means of receiver operating
characteristic curve. The conventional (150mg/dL) and the prognostic cutoff values of triglycerides were used as independent
predictors in separate multivariable Cox regression models adjusted for age, sex, body mass index, total and high-density
lipoprotein cholesterol, serum uric acid, arterial hypertension, diabetes, chronic renal disease, smoking habit, and use of antihypertensive and lipid-lowering drugs. During 139375 person-years of follow-up, 1601 participants experienced cardiovascular events. Receiver operating characteristic curve showed that 89mg/dL (95% CI, 75.8–103.3, sensitivity 76.6, specificity
34.1, P<0.0001) was the prognostic cutoff value for cardiovascular events. Both cutoff values of triglycerides, the conventional
and the newly identified, were accepted as multivariate predictors in separate Cox analyses, the hazard ratios being 1.211
(95% CI, 1.063–1.378, P=0.004) and 1.150 (95% CI, 1.021–1.295, P=0.02), respectively.
CONCLUSIONS: Lower (89mg/dL) than conventional (150mg/dL) prognostic cutoff value of triglycerides for cardiovascular
events does exist and is associated with increased cardiovascular risk in an Italian cohor
Evidence for the Higgs-boson Yukawa coupling to tau leptons with the ATLAS detector
Results of a search for H → τ τ decays are presented, based on the full set of proton-proton collision data recorded by the ATLAS experiment at the LHC during 2011 and 2012. The data correspond to integrated luminosities of 4.5 fb−1 and 20.3 fb−1 at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV respectively. All combinations of leptonic (τ → `νν¯ with ` = e, µ) and hadronic (τ → hadrons ν) tau decays are considered. An excess of events over the expected background from other Standard Model processes is found with an observed (expected) significance of 4.5 (3.4) standard deviations. This excess provides evidence for the direct coupling of the recently discovered Higgs boson to fermions. The measured signal strength, normalised to the Standard Model expectation, of µ = 1.43 +0.43 −0.37 is consistent with the predicted Yukawa coupling strength in the Standard Model
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
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