149 research outputs found

    Patterns and localized structures in bistable semiconductor resonators

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    We report experiments on spatial switching dynamics and steady state structures of passive nonlinear semiconductor resonators of large Fresnel number. Extended patterns and switching front dynamics are observed and investigated. Evidence of localization of structures is given.Comment: 5 pages with 9 figure

    Liver Stiffness Measurement and Biochemical Markers in Senegalese Chronic Hepatitis B Patients with Normal ALT and High Viral Load

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    Despite the high prevalence of chronic hepatitis B (CHB) in Africa, few studies have been performed among African patients. We sought to evaluate liver stiffness measurement by FibroScan® (LSM) and two biochemical scores (FibroTest®, Fibrometer®) to diagnose liver fibrosis in Senegalese CHB patients with HBV plasma DNA load ≥3.2 log(10) IU/mL and normal alanine aminotransferase (ALT) values.LSM and liver fibrosis biochemical markers were performed on 225 consecutive HBV infected Senegalese patients with high viral load. Patients with an LSM range between 7 and 13 kPa underwent liver biopsy (LB). Two experienced liver pathologists performed histological grading using Metavir and Ishak scoring.225 patients were evaluated (84% male) and LB was performed in 69 patients, showing F2 and F3 fibrosis in 17% and 10% respectively. In these patients with a 7-13 kPa range of LSM, accuracy for diagnosis of significant fibrosis according to LB was unsatisfactory for all non-invasive markers with AUROCs below 0.70. For patients with LSM values below 7 kPa, FibroTest® (FT), and Fibrometer® (FM) using the cut-offs recommended by the test promoters suggested a fibrosis in 18% of cases for FT (8% severe fibrosis) and 8% for FM. For patients with LSM values greater than 13 kPa, FT, FM suggested a possible fibrosis in 73% and 70%, respectively.In highly replicative HBV-infected African patients with normal ALT and LSM value below 13 kPa, FibroScan®, FibroTest® or Fibrometer® were unsuitable to predict the histological liver status of fibrosis

    2012 Activity Report of the Regional Research Programme on Hadrontherapy for the ETOILE Center

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    2012 is the penultimate year of financial support by the CPER 2007-2013 for ETOILE's research program, sustained by the PRRH at the University Claude Bernard. As with each edition we make the annual review of the research in this group, so active for over 12 years now. Over the difficulties in the decision-making process for the implementation of the ETOILE Center, towards which all our efforts are focussed, some "themes" (work packages) were strengthened, others have progressed, or have been dropped. This is the case of the eighth theme (technological developments), centered around the technology for rotative beam distribution heads (gantries) and, after being synchronized with the developments of ULICE's WP6, remained so by ceasing its activities, coinciding also with the retirement of its historic leader at IPNL, Marcel Bajard. Topic number 5 ("In silico simulations") has suffered the departure of its leader, Benjamin Ribba, although the work has still been provided by Branka Bernard, a former postdoctoral fellow in Lyon Sud, and now back home in Croatia, still in contract with UCBL for the ULICE project. Aside from these two issues (and the fact that the theme "Medico-economical simulations" is now directly linked to the first one ("Medical Project"), the rest of the teams are growing, as evidenced by the publication statistics at the beginning of this report. This is obviously due to the financial support of our always faithful regional institutions, but also to the synergy that the previous years, the European projects, the arrival of the PRIMES LabEx, and the national France Hadron infrastructure have managed to impulse. The Rhone-Alpes hadron team, which naturally includes the researchers of LPC at Clermont, should also see its influence result in a strong presence in France Hadron's regional node, which is being organized. The future of this regional research is not yet fully guaranteed, especially in the still uncertain context of ETOILE, but the tracks are beginning to emerge to allow past and present efforts translate into a long future that we all want to see established. Each of the researchers in PRRH is aware that 2013 will be (and already is) the year of great challenge : for ETOILE, for the PRRH, for hadron therapy in France, for French hadrontherapy in Europe (after the opening and beginning of treatments in the German [HIT Heidelberg, Marburg], Italian [CNAO, Pavia] and Austrian [MedAustron, Wien Neuerstadt]) centers. Let us meet again in early 2014 for a comprehensive review of the past and a perspective for the future ..

    Clinical significance of circulating anti-p53 antibodies in European patients with hepatocellular carcinoma

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    p53 alterations are considered to be predictive of poor prognosis in hepatocellular carcinoma (HCC) and may induce a humoral response. Anti-p53 serum antibodies were assessed by enzyme-linked immunosorbent assay (ELISA) using purified recombinant human p53 on 130 European HCC patients before treatment and during the clinical course of the disease. p53 immunohistochemistry was performed on tumours from the 52 patients who underwent surgery, and DNA sequencing analysis was initiated when circulating anti-p53 antibodies were detected. Nine (7%) HCC patients had anti-p53 serum antibodies before treatment. During a mean period of 30 months of follow-up, all the negative patients remained negative, even when recurrence was observed. Of the nine positive patients, eight were still positive 12–30 months after surgery. The presence of anti-p53 serum antibodies was correlated neither with mutation of the p53 gene nor the serum alpha-fetoprotein levels and clinicopathological characterics of the tumours. However, a greater incidence of vascular invasion and accumulation of p53 protein were observed in the tumours of these patients (P < 0.03 and P < 0.01 respectively) as well as a better survival rate without recurrence (P = 0.05). In conclusion, as was recently shown in pancreatic cancer, anti-p53 serum antibodies may constitute a marker of relative ‘good prognosis’ in a subgroup of patients exhibiting one or several markers traditionally thought to be of bad prognosis. © 1999 Cancer Research Campaig

    Prediction of Liver-Related Events Using Fibroscan in Chronic Hepatitis B Patients Showing Advanced Liver Fibrosis

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    Liver stiffness measurement (LSM) using transient elastography (FibroScan®) can assess liver fibrosis noninvasively. This study investigated whether LSM can predict the development of liver-related events (LREs) in chronic hepatitis B (CHB) patients showing histologically advanced liver fibrosis.Between March 2006 and April 2010, 128 CHB patients with who underwent LSM and liver biopsy (LB) before starting nucleot(s)ide analogues and showed histologically advanced fibrosis (≥F3) with a high viral loads [HBV DNA ≥2,000 IU/mL] were enrolled. All patients were followed regularly to detect LRE development, including hepatic decompensation (variceal bleeding, ascites, hepatic encephalopathy, spontaneous bacterial peritonitis, hepatorenal syndrome) and hepatocellular carcinoma (HCC).The mean age of the patient (72 men, 56 women) was 52.2 years. During the median follow-up period [median 27.8 (12.6-61.6) months], LREs developed in 19 (14.8%) patients (five with hepatic decompensation, 13 with HCC, one with both). Together with age, multivariate analysis identified LSM as an independent predictor of LRE development [P<0.044; hazard ratio (HR), 1.038; 95% confidence interval (CI), 1.002-1.081]. When the study population was stratified into two groups using the optimal cutoff value (19 kPa), which maximized the sum of sensitivity (61.1%) and specificity (86.2%) from a time-dependent receiver operating characteristic curve, patients with LSM>19 kPa were at significantly greater risk than those with LSM≤19 kPa for LRE development (HR, 7.176; 95% CI, 2.257-22.812; P = 0.001).LSM can be a useful predictor of LRE development in CHB patients showing histologically advanced liver fibrosis

    Beyond What Meets the Eye: Imaging and Imagining Wood Mechanical–Structural Properties

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    Abstract: Wood presents a hierarchical structure, containing features at all length scales: from the tracheids or vessels that make up its cellular structure, through to the microfibrils within the cell walls, down to the molecular architecture of the cellulose, lignin, and hemicelluloses that comprise its chemical makeup. This structure renders it with high mechanical (e.g., modulus and strength) and interesting physical (e.g., optical) properties. A better understanding of this structure, and how it plays a role in governing mechanical and other physical parameters, will help to better exploit this sustainable resource. Here, recent developments on the use of advanced imaging techniques for studying the structural properties of wood in relation to its mechanical properties are explored. The focus is on synchrotron nuclear magnetic resonance spectroscopy, X‐ray diffraction, X‐ray tomographical imaging, Raman and infrared spectroscopies, confocal microscopy, electron microscopy, and atomic force microscopy. Critical discussion on the role of imaging techniques and how fields are developing rapidly to incorporate both spatial and temporal ranges of analysis is presented

    The "Statinth" wonder of the world: a panacea for all illnesses or a bubble about to burst

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    After the introduction of statins in the market as effective lipid lowering agents, they were shown to have effects other than lipid lowering. These actions were collectively referred to as 'pleiotropic actions of statins.' Pleiotropism of statins formed the basis for evaluating statins for several indications other than lipid lowering. Evidence both in favour and against is available for several of these indications. The current review attempts to critically summarise the available data for each of these indications

    HFE MUTATIONS AND IRON OVERLOAD IN PATIENTS WITH ALCOHOLIC LIVER DISEASE

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    Context Alcoholic liver disease (ALD) is generally associated with iron overload, which may contribute to its pathogenesis, through increased oxidative stress and cellular damage. There are conflicting reports in literature about hemochromatosis (HFE) gene mutations and the severity of liver disease in alcoholic patients. Objectives To compare the prevalence of mutations in the hemochromatosis (HFE) gene between patients with ALD and healthy controls; to assess the relation of HFE mutations with liver iron stores and liver disease severity. Methods Liver biopsy specimens were obtained from 63 ALD patients (during routine treatment) and 52 healthy controls (during elective cholecystectomy). All individuals underwent routine liver function tests and HFE genotyping (to detect wild-type sequences and C282Y, H63D, S65C, E168Q, E168X, V59M, H63H, P160delC, Q127H, Q283P, V53M and W164X mutations). Associations between HFE mutations and risk of excessive liver iron stores, abnormal serum ferritin, liver fibrosis, or necroinflammatory activity were assessed by multivariate logistic regression analysis. Results ALD patients had significantly higher serum ferritin and transferrin saturation than controls (both P Contexto A doen&#231;a hep&#225;tica alco&#243;lica (DHA) est&#225; geralmente associada &#224; sobrecarga de ferro, que pode contribuir para a sua patog&#234;nese, atrav&#233;s do aumento do estresse oxidativo e dano celular. As descri&#231;&#245;es existentes na literatura sobre a associa&#231;&#227;o entre muta&#231;&#245;es HFE e a gravidade da DHA nem sempre s&#227;o concordantes. Objetivos Comparar a preval&#234;ncia de muta&#231;&#245;es HFE entre um grupo de pacientes com DHA e uma popula&#231;&#227;o de controle. Avaliar a rela&#231;&#227;o entre muta&#231;&#245;es HFE e os dep&#243;sitos de ferro hep&#225;tico. Avaliar se a presen&#231;a dessas muta&#231;&#245;es est&#225; associada com a gravidade da DHA. M&#233;todos Compararam-se 63 pacientes com DHA que efetuaram biopsia hep&#225;tica com 52 controles saud&#225;veis. A genotipagem HFE (wild type, C282Y, H63D, S65C, E168Q, E168X, V59M, H63H, P160delC, Q127H, Q283P, V53M, W164X) e uma avalia&#231;&#227;o laboratorial de rotina (incluindo cin&#233;tica do ferro) foram feitos em todos os indiv&#237;duos. Realizou-se regress&#227;o log&#237;stica multivariada nos casos para avaliar se a presen&#231;a de muta&#231;&#245;es HFE estava relacionada com risco aumentado de dep&#243;sitos de ferro hep&#225;tico aumentados, ferritina s&#233;rica anormal, fibrose hep&#225;tica significativa ou atividade necroinflamat&#243;ria. Resultados Os pacientes apresentaram ferritina s&#233;rica e satura&#231;&#227;o da transferrina mais elevadas que os controles, mas n&#227;o existiram diferen&#231;as significativas na distribui&#231;&#227;o de muta&#231;&#245;es HFE entre pacientes e controles. Considerando apenas os pacientes, o risco relativo de estes apresentarem pelo menos uma muta&#231;&#227;o HFE e dep&#243;sitos de ferro hep&#225;tico significativos foi de 17.23 (CI 95% 2.09-142.34, P = 0.008). Contudo, a presen&#231;a de pelo menos uma muta&#231;&#227;o HFE n&#227;o esteve associada ao risco significativamente aumentado de fibrose ou atividade necroinflamat&#243;ria significativas. O fator mais determinante para apresentar ferritina s&#233;rica acima do normal foi a presen&#231;a de alcoolismo ativo, com risco relativo de 8.87 (CI 95% 2.11-34.78, P = 0.003). Conclus&#245;es N&#227;o existiram diferen&#231;as na distribui&#231;&#227;o de muta&#231;&#245;es HFE entre pacientes com DHA e controles normais. Nos pacientes, o achado de pelo menos uma muta&#231;&#227;o HFE aumentou o risco de ter dep&#243;sitos de ferro hep&#225;tico mais elevados, mas n&#227;o para ter fibrose ou atividade necroinflamat&#243;ria significativas

    Barrier layer at metal-ceramic interface in ferroelectric MIM structures

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    The influence of interfacial contact effects in a ferroelectric Metal-Insulator-Metal (MIM) structure is described. Lead Titano-Zirconate (PZT) material is deposited by a sol-gel technique on a platinum bottom electrode. Top electrodes are deposited after PZT annealing. The ferroelectric properties of the PZT (related to the hysteresis curve) are strongly dependent on the thermal treatments of both electrodes. Preannealing of the bottom electrode before PZT deposition, as well as post annealing of the top electrodes, lead to an improvement of the properties (increase in remanent polarization and in dielectric constant). This is explained by the suppression of the contact barrier at the interfaces between PZT and metal. The switching of the domains in the subsaturated regime of the hysteresis can be modelled by introducing a non ferroelectric barrier at the interfaces when the electrodes are not annealed.
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