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Coverage-dependent molecular tilt of carbon monoxide chemisorbed on Pt{110}: A combined LEED and DFT structural analysis
The adsorption of carbon monoxide on the Pt{110} surface at coverages of 0.5 ML and 1.0 ML was investigated
using quantitative low-energy electron diffraction (LEED IV) and density-functional theory (DFT). At 0.5
ML CO lifts the reconstruction of the clean surface but does not form an ordered overlayer. At the saturation
coverage, 1.0 ML, a well-ordered p(2×1) superstructure with glide line symmetry is formed. It was confirmed
that the CO molecules adsorb on top of the Pt atoms in the top-most substrate layer with the molecular
axes tilted by ±22° with respect to the surface normal in alternating directions away from the close
packed rows of Pt atoms. This is accompanied by significant lateral shifts of 0.55 Å away from the atop
sites in the same direction as the tilt. The top-most substrate layer relaxes inwards by −4% with respect to
the bulk-terminated atom positions, while the consecutive layers only show minor relaxations. Despite the
lack of long-range order in the 0.5 ML CO layer it was possible to determine key structural parameters by
LEED IV using only the intensities of the integer-order spots. At this coverage CO also adsorbs on atop sites
with the molecular axis closer to the surface normal (b10°). The average substrate relaxations in each
layer are similar for both coverages and consistent with DFT calculations performed for a variety of ordered
structures with coverages of 1.0 ML and 0.5 ML
Corticosteroids and hip fracture risk in elderly respiratory patients: EPIC-Greece cohort
INTRODUCTION: In an ageing population the prevalence of osteoporosis and chronic respiratory diseases is expected to increase in the near future. Interestingly, several forms of corticosteroids, drugs implicated in osteoporosis pathogenesis, are prescribed to respiratory patients without taking into consideration their age and risk for osteoporotic fractures. The aim of this study was to investigate the risk for hip fracture of the elder individuals who are taking corticosteroids for respiratory disease, including inhalers. MATERIAL AND METHODS: Data on incident hip fractures were collected through the active follow-up for all individuals participating in the Greek segment of the European Prospective Investigation into Cancer and Nutrition (EPIC-Greece) study who were 60 years or older at recruitment and reported "a doctor's diagnosis" of respiratory disease. Socio-demographic, life-style, health status data and use of corticosteroids were recorded from the baseline and follow-up questionnaires. Cox regression models were applied to estimate hazard ratios (HRs) adjusting for relevant confounders. RESULTS: We observed an increase in hip fracture risk with corticosteroid intake overall (HR: 1.68, 95% CI: 0.85-3.34). Increased risk persisted when we restricted our analysis to participants taking any form of corticosteroids for obstructive lung disease (HR: 1.40, 95% CI: 0.64-3.06) and to those using only inhalers (HR: 1.58, 95% CI: 0.71-3.50). However, these positive associations did not reach the nominal level of significance probably due to the small number of participants with hip fractures during follow-up. CONCLUSION: Hip fracture risk should be taken into consideration when recommending corticosteroids to the elder respiratory patients, including inhalers
Diffuse Idiopathic Skeletal Hyperostosis (DISH) and non small cell lung cancer: case presentation and review of the literature
Diffuse idiopathic skeletal hyperostosis (DISH), also known as Forestier’s disease, is a systemic non inflammatory disease of unknown cause. It is characterized by the presence of osteophytes due to calcification and ossification of spinal ligaments and entheses. Moreover, diffuse idiopathic skeletal hyperostosis has been associated with a variety of metabolic disorders. However, to the best of our knowledge no association with non small cell lung cancer (NSCLC) has been reported so far. In the present study we report a case of a patient with NSCLC and DISH.Diffuse idiopathic skeletal hyperostosis (DISH), also known as Forestier’s disease, is a systemic non inflammatory disease of unknown cause. It is characterized by the presence of osteophytes due to calcification and ossification of spinal ligaments and entheses. Moreover, diffuse idiopathic skeletal hyperostosis has been associated with a variety of metabolic disorders. However, to the best of our knowledge no association with non small cell lung cancer (NSCLC) has been reported so far. In the present study we report a case of a patient with NSCLC and DISH
Epidemiology of interstitial lung diseases in Greece
SummaryIntroductionFew data are available on the epidemiology of interstitial lung diseases (ILDs), especially after the current classification of idiopathic interstitial pneumonias. The aim of this study is to provide data on the epidemiology of ILDs in Greece, under the ATS/ERS international consensus.MethodsDepartments of Pneumonology were contacted and asked to complete a questionnaire for every case of ILD that was alive on 2004 as well as for every new case from 1st January 2004 to 31st December 2004. Questions on the patients' demographic data, the exact diagnosis and the procedures used to establish the diagnosis were included. Centers covering about 60% of the Greek population have been analyzed.ResultsA total of 967 cases have been registered. The estimated prevalence of ILDs is 17.3 cases per 100,000 inhabitants. The estimated annual incidence of ILDs is 4.63 new cases per 100,000 inhabitants. The most frequent disease is sarcoidosis (34.1%), followed in decreasing order by idiopathic pulmonary fibrosis (19.5%), ILD associated with collagen vascular diseases (12.4%), cryptogenic organizing pneumonia (5.3%), histiocytosis (3.8%), and hypersensitivity pneumonitis (2.6%). Unclassified ILD or not otherwise specified accounted for the 8.5% of prevalent cases.ConclusionsThese data suggest that sarcoidosis and idiopathic pulmonary fibrosis are the most frequent ILDs in our population. In comparison with the few previous reports, interesting dissimilarities have been observed
Edge-based nonlinear diffusion for finite element approximations of convection–diffusion equations and its relation to algebraic flux-correction schemes
The final publication is available at Springer via http://dx.doi.org/10.1007/s00211-016-0808-zFor the case of approximation of convection–diffusion equations using piecewise affine continuous finite elements a new edge-based nonlinear diffusion operator is proposed that makes the scheme satisfy a discrete maximum principle. The diffusion operator is shown to be Lipschitz continuous and linearity preserving. Using these properties we provide a full stability and error analysis, which, in the diffusion dominated regime, shows existence, uniqueness and optimal convergence. Then the algebraic flux correction method is recalled and we show that the present method can be interpreted as an algebraic flux correction method for a particular definition of the flux limiters. The performance of the method is illustrated on some numerical test cases in two space dimensions
Neuronal LRP4 regulates synapse formation in the developing CNS
The low-density lipoprotein receptor-related protein 4 (LRP4) is essential in muscle fibers for the establishment of the neuromuscular junction. Here, we show that LRP4 is also expressed by embryonic cortical and hippocampal neurons, and that downregulation of LRP4 in these neurons causes a reduction in density of synapses and number of primary dendrites. Accordingly, overexpression of LRP4 in cultured neurons had the opposite effect inducing more but shorter primary dendrites with an increased number of spines. Transsynaptic tracing mediated by rabies virus revealed a reduced number of neurons presynaptic to the cortical neurons in which LRP4 was knocked down. Moreover, neuron-specific knockdown of LRP4 by in utero electroporation of LRP4 miRNA in vivo also resulted in neurons with fewer primary dendrites and a lower density of spines in the developing cortex and hippocampus. Collectively, our results demonstrate an essential and novel role of neuronal LRP4 in dendritic development and synaptogenesis in the CNS
Pirfenidone in idiopathic pulmonary fibrosis:expert panel discussion on the management of drug-related adverse events
Pirfenidone is currently the only approved therapy for idiopathic pulmonary fibrosis, following studies demonstrating that treatment reduces the decline in lung function and improves progression-free survival. Although generally well tolerated, a minority of patients discontinue therapy due to gastrointestinal and skin-related adverse events (AEs). This review summarizes recommendations based on existing guidelines, research evidence, and consensus opinions of expert authors, with the aim of providing practicing physicians with the specific clinical information needed to educate the patient and better manage pirfenidone-related AEs with continued pirfenidone treatment. The main recommendations to help prevent and/or mitigate gastrointestinal and skin-related AEs include taking pirfenidone during (or after) a meal, avoiding sun exposure, wearing protective clothing, and applying a broad-spectrum sunscreen with high ultraviolet (UV) A and UVB protection. These measures can help optimize AE management, which is key to maintaining patients on an optimal treatment dose.Correction in: Advances in Therapy, Volume 31, Issue 5, pp 575-576 , doi: 10.1007/s12325-014-0118-8</p
Patterns in metabolite profile are associated with risk of more aggressive prostate cancer: A prospective study of 3,057 matched case-control sets from EPIC
Metabolomics may reveal novel insights into the etiology of prostate cancer, for which few risk factors are established. We investigated the association between patterns in baseline plasma metabolite profile and subsequent prostate cancer risk, using data from 3,057 matched case-control sets from the European Prospective Investigation into Cancer and Nutrition (EPIC). We measured 119 metabolite concentrations in plasma samples, collected on average 9.4 years before diagnosis, by mass spectrometry (AbsoluteIDQ p180 Kit, Biocrates Life Sciences AG). Metabolite patterns were identified using treelet transform, a statistical method for identification of groups of correlated metabolites. Associations of metabolite patterns with prostate cancer risk (OR1SD ) were estimated by conditional logistic regression. Supplementary analyses were conducted for metabolite patterns derived using principal component analysis and for individual metabolites. Men with metabolite profiles characterized by higher concentrations of either phosphatidylcholines or hydroxysphingomyelins (OR1SD = 0.77, 95% confidence interval 0.66-0.89), acylcarnitines C18:1 and C18:2, glutamate, ornithine and taurine (OR1SD = 0.72, 0.57-0.90), or lysophosphatidylcholines (OR1SD = 0.81, 0.69-0.95) had lower risk of advanced stage prostate cancer at diagnosis, with no evidence of heterogeneity by follow-up time. Similar associations were observed for the two former patterns with aggressive disease risk (the more aggressive subset of advanced stage), while the latter pattern was inversely related to risk of prostate cancer death (OR1SD = 0.77, 0.61-0.96). No associations were observed for prostate cancer overall or less aggressive tumor subtypes. In conclusion, metabolite patterns may be related to lower risk of more aggressive prostate tumors and prostate cancer death, and might be relevant to etiology of advanced stage prostate cancer
Intake of individual fatty acids and risk of prostate cancer in the European prospective investigation into cancer and nutrition
The associations of individual dietary fatty acids with prostate cancer risk have not been examined comprehensively. We examined the prospective association of individual dietary fatty acids with prostate cancer risk overall, by tumor subtypes, and prostate cancer death. 142,239 men from the European Prospective Investigation into Cancer and Nutrition who were free from cancer at recruitment were included. Dietary intakes of individual fatty acids were estimated using center-specific validated dietary questionnaires at baseline and calibrated with 24-hour recalls. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). After an average follow-up of 13.9 years, 7,036 prostate cancer cases and 936 prostate cancer deaths were ascertained. Intakes of individual fatty acids were not related to overall prostate cancer risk. There was evidence of heterogeneity in the association of some short chain saturated fatty acids with prostate cancer risk by tumor stage (Pheterogeneity <0.015), with a positive association with risk of advanced stage disease for butyric acid (4:0; HR1SD =1.08; 95%CI=1.01-1.15; P-trend=0.026). There were no associations with fatal prostate cancer, with the exception of a slightly higher risk for those who consumed more eicosenoic acid (22:1n-9c; HR1SD =1.05; 1.00-1.11; P-trend=0.048) and eicosapentaenoic acid (20:5n-3c; HR1SD =1.07; 1.00-1.14; P-trend=0.045). There was no evidence that dietary intakes of individual fatty acids were associated with overall prostate cancer risk. However, a higher intake of butyric acid might be associated with a higher risk of advanced, whereas intakes of eicosenoic and eicosapentaenoic acids might be positively associated with fatal prostate cancer risk. This article is protected by copyright. All rights reserved
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