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Find video protocols related to scientific articles indexed in Pubmed.
Chemical imaging of single catalyst particles with scanning ?-XANES-CT and ?-XRF-CT.
Phys Chem Chem Phys
PUBLISHED: 11-20-2014
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The physicochemical state of a catalyst is a key factor in determining both activity and selectivity; however these materials are often not structurally or compositionally homogeneous. Here we report on the 3-dimensional imaging of an industrial catalyst, Mo-promoted colloidal Pt supported on carbon. The distribution of both the active Pt species and Mo promoter have been mapped over a single particle of catalyst using microfocus X-ray fluorescence computed tomography. X-ray absorption near edge spectroscopy (XANES) and extended X-ray absorption fine structure revealed a mixed local coordination environment, including the presence of both metallic Pt clusters and Pt chloride species, but also no direct interaction between the catalyst and Mo promoter. We also report on the benefits of scanning ?-XANES computed tomography for chemical imaging, allowing for 2- and 3-dimensional mapping of the local electronic and geometric environment, in this instance for both the Pt catalyst and Mo promoter throughout the catalyst particle.
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Prognostic Factors for Sudden Drops in Hearing Level After Minor Head Injury in Patients With an Enlarged Vestibular Aqueduct: A Meta-analysis.
Otol. Neurotol.
PUBLISHED: 11-20-2014
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To identify factors associated with sudden drops in hearing level after minor head trauma in patients with an enlarged vestibular aqueduct (EVA).
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The mechanically induced structural disorder in barium hexaferrite, BaFe12O19, and its impact on magnetism.
Faraday Discuss.
PUBLISHED: 11-20-2014
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The response of the structure of the M-type barium hexaferrite (BaFe12O19) to mechanical action through high-energy milling and its impact on the magnetic behaviour of the ferrite are investigated. Due to the ability of the (57)Fe Mössbauer spectroscopic technique to probe the environment of the Fe nuclei, a valuable insight on a local atomic scale into the mechanically induced changes in the hexagonal structure of the material is obtained. It is revealed that the milling of BaFe12O19 results in the deformation of its constituent polyhedra (FeO6 octahedra, FeO4 tetrahedra and FeO5 triangular bi-pyramids) as well as in the mechanically triggered transition of the Fe(3+) cations from the regular 12k octahedral sites into the interstitial positions provided by the magnetoplumbite structure. The response of the hexaferrite to the mechanical treatment is found to be accompanied by the formation of a non-uniform nanostructure consisting of an ordered crystallite surrounded/separated by a structurally disordered surface shell/interface region. The distorted polyhedra and the non-equilibrium cation distribution are found to be confined to the amorphous near-surface layers of the ferrite nanoparticles with the thickness extending up to about 2 nm. The information on the mechanically induced short-range structural disorder in BaFe12O19 is complemented by an investigation of its magnetic behaviour on a macroscopic scale. It is demonstrated that the milled ferrite nanoparticles exhibit a pure superparamagnetism at room temperature. As a consequence of the far-from-equilibrium structural disorder in the surface shell of the nanoparticles, the mechanically treated BaFe12O19 exhibits a reduced magnetization and an enhanced coercivity.
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Voluntary Work and the Relationship With Unemployment, Health, and Well-Being: A Two-Year Follow-Up Study Contrasting a Materialistic and Psychosocial Pathway Perspective.
J Occup Health Psychol
PUBLISHED: 11-18-2014
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In the present study we contrast materialistic (i.e., income and economic inequality) and psychosocial (i.e., social circumstances) pathway perspectives on whether volunteering while being unemployed mitigates the well-documented negative effects of unemployment on health, health behaviors, and well-being. We test our hypotheses using data from the 2010 and 2012 waves of the Swedish Longitudinal Occupational Study of Health (SLOSH; n = 717). This is a nationally representative, longitudinal, cohort survey. We compared groups of individuals who were (a) unemployed and volunteering during both SLOSH waves (n = 58), (b) unemployed and not volunteering during both SLOSH waves (n = 194), (c) employed and volunteering during both SLOSH waves (n = 139), and (d) employed and not volunteering during both SLOSH waves (n = 326). Conducting a path analysis in Mplus, we examined the interaction effects between labor market status (i.e., employed or unemployed) and voluntary work (i.e., volunteering or not) when predicting changes in health, health behaviors, and psychological well-being. Our results indicate that volunteering during unemployment significantly decreased the likelihood to smoke, the amount of cigarettes smoked, the likelihood of consuming alcohol, and the likelihood of being diagnosed with hypertension. These results support a psychosocial pathway perspective. For all other indicators no such buffering interaction effect was obtained, thereby supporting a materialistic pathway perspective. Nevertheless, for some indicators, volunteering was found to be beneficial for both the unemployed and employed. Consequently, integrating both perspectives might offer a better explanation for the onset of ill-health and ill-being. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
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Fourier transform holography with extended references using a coherent ultra-broadband light source.
Opt Express
PUBLISHED: 11-18-2014
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We demonstrate a technique that enables lensless holographic imaging with extended reference structures, using ultra-broadband radiation sources for illumination. We show that this 'two-pulse imaging' approach works with one- and two-dimensional HERALDO reference structures, and demonstrate that the obtained spectrally resolved data can be used to improve the signal-to-noise ratio in the final image. Intensity stitching of multiple exposures is applied to increase the detected dynamic range, leading to an improved image reconstruction. Furthermore, we show that a combination of holography and iterative phase retrieval can be used to obtain high-quality images quickly and reliably, by using the HERALDO reconstruction as the initial support constraint in the iterative phase retrieval algorithm. A signal-to-noise improvement of two orders of magnitude is achieved compared to the basic HERALDO result.
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Lattice Matching as the Determining Factor for Molecular Tilt and Multilayer Growth Mode of the Nanographene Hexa-peri-hexabenzocoronene.
ACS Appl Mater Interfaces
PUBLISHED: 11-15-2014
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The microstructure, morphology and growth dynamics of hexa-peri-hexabenzocoronene (HBC, C42H18) thin films deposited on inert substrates of similar surface energies are studied with particular emphasis on the influence of substrate symmetry and substrate-molecule lattice matching on the resulting films of this material. By combining atomic force microscopy (AFM) with x-ray diffraction (XRD), x-ray absorption spectroscopy (NEXAFS) and in-situ x-ray reflectivity (XRR) measurements, it is shown that HBC forms polycrystalline films on SiO2, where molecules are uprightly oriented and adopt the known bulk structure. Remarkably, HBC films deposited on highly oriented pyrolytic graphite (HOPG) exhibit a new, substrate induced polymorph, where all molecules adopt a recumbent orientation with planar ?-stacking. Formation of this new phase, however, depends critically on the coherence of the underlying graphite lattice, since HBC grown on defective HOPG reveals the same orientation and phase as on SiO2. These results therefore demonstrate that the resulting film structure and morphology are not solely governed by the adsorption energy, but also by the presence or absence of symmetry- and lattice-matching between substrate and admolecules. Moreover, it highlights that weakly interacting substrates of high quality and coherence can be useful to induce new polymorphs with distinctly different molecular arrangements than the bulk structure.
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Relationship between insulin resistance and beta cell dysfunction in subphenotypes of pre-diabetes and type 2 diabetes.
J. Clin. Endocrinol. Metab.
PUBLISHED: 11-12-2014
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Context: There is little overlap between diabetes diagnosis by HbA1c and blood glucose, and it is unclear which pathophysiological defects are captured when using HbA1c for diagnosis. Objective: We examined and compared the relationship between insulin sensitivity and beta cell function in different sub-phenotypes of pre-diabetes and type 2 diabetes (T2D). Design, setting and participants: A cross-sectional analysis of the Danish ADDITION-PRO study was performed (n=1,713). Participants without known diabetes were classified into subgroups of pre-diabetes and T2D based on fasting or 2-hour glucose criteria or HbA1c. Insulin sensitivity and insulin release were determined from glucose and insulin concentrations during the oral glucose tolerance test, and disposition indices were calculated. Results: Individuals with pre-diabetes or T2D diagnosed by fasting glucose had lower absolute insulin release (P?0.01) and higher insulin sensitivity after glucose intake (P?0.01), but similar disposition index (P?0.36), compared with individuals with elevated 2-hour glucose concentrations. Individuals with HbA1c-defined T2D or pre-diabetes had a mixture of the pathophysiological defects observed in the glucose-defined subgroups, and individuals with normoglycemia by HbA1c had worse pathophysiological abnormalities than individuals with normoglycemia by the glucose criteria. Conclusions: On average, the diagnostic HbA1c criteria for diabetes and pre-diabetes identified individuals with a mixture of the pathophysiological characteristics found when using glucose criteria, but the diversity and pathophysiology captured by the OGTT cannot be captured when applying the more simple HbA1c criteria. Whether disease progression and prognosis will differ in individuals diagnosed by fasting glucose, 2-h glucose or HbA1c should be examined in longitudinal studies.
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Prediction of individual response to anticancer therapy: historical and future perspectives.
Cell. Mol. Life Sci.
PUBLISHED: 10-27-2014
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Since the introduction of chemotherapy for cancer treatment in the early 20th century considerable efforts have been made to maximize drug efficiency and at the same time minimize side effects. As there is a great interpatient variability in response to chemotherapy, the development of predictive biomarkers is an ambitious aim for the rapidly growing research area of personalized molecular medicine. The individual prediction of response will improve treatment and thus increase survival and life quality of patients. In the past, cell cultures were used as in vitro models to predict in vivo response to chemotherapy. Several in vitro chemosensitivity assays served as tools to measure miscellaneous endpoints such as DNA damage, apoptosis and cytotoxicity or growth inhibition. Twenty years ago, the development of high-throughput technologies, e.g. cDNA microarrays enabled a more detailed analysis of drug responses. Thousands of genes were screened and expression levels were correlated to drug responses. In addition, mutation analysis became more and more important for the prediction of therapeutic success. Today, as research enters the area of -omics technologies, identification of signaling pathways is a tool to understand molecular mechanism underlying drug resistance. Combining new tissue models, e.g. 3D organoid cultures with modern technologies for biomarker discovery will offer new opportunities to identify new drug targets and in parallel predict individual responses to anticancer therapy. In this review, we present different currently used chemosensitivity assays including 2D and 3D cell culture models and several -omics approaches for the discovery of predictive biomarkers. Furthermore, we discuss the potential of these assays and biomarkers to predict the clinical outcome of individual patients and future perspectives.
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Fast Adaptive Responses in the Oral Jaw of Lake Victoria Cichlids.
Evolution
PUBLISHED: 10-07-2014
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Rapid morphological changes in response to fluctuating natural environments are a common phenomenon in species that undergo adaptive radiation. The dramatic ecological changes in Lake Victoria provide a unique opportunity to study environmental effects on cichlid morphology. This study shows how four haplochromine cichlids adapted their premaxilla to a changed diet over the past 30 years. Directly after the diet change towards larger and faster prey in the late 1980s, the premaxilla (upper jaw) changed in a way that is in agreement with a more food manipulating feeding style. During the 2000s, two zooplanktivorous species showed a reversal of morphological changes after returning to their original diet, while two other species showed no reversal of diet and morphology. These rapid changes indicate a potential for extremely fast adaptive responses to environmental fluctuations, which are likely inflicted by competition release and increase, and might have a bearing on the ability of haplochromines to cope with environmental changes. These responses could be due to rapid genetic change or phenotypic plasticity, for which there is ample evidence in cichlid fish structures associated with food capture and processing. These versatile adaptive responses are likely to have contributed to the fast adaptive radiation of haplochromines. This article is protected by copyright. All rights reserved.
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High numbers of mobilized CD34+ cells collected in AML in first remission are associated with high relapse risk irrespective of treatment with autologous peripheral blood SCT or autologous BMT.
Bone Marrow Transplant.
PUBLISHED: 09-18-2014
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The faster hematopoietic recovery after autologous peripheral blood SCT (APBSCT) in patients with AML may be offset by an increased relapse risk as compared with autologous BMT (ABMT). The EORTC and GIMEMA Leukemia Groups conducted a trial (AML-10) in which they compared, as second randomization, APBSCT and ABMT in first CR patients without an HLA compatible donor. A total of 292 patients were randomized. The 5-year DFS rate was 41% in the APBSCT arm and 46% in the ABMT arm with a hazard ratio (HR) of 1.17; 95% confidence interval=0.85-1.59; P=0.34. The 5-year cumulative relapse incidence was 56% vs 49% (P=0.26), and the 5-year OS 50% and 55% (P=0.6) in the APBSCT and ABMT groups, respectively. APBSCT was associated with significantly faster recovery of neutrophils and platelets, shorter duration of hospitalization, reduced need of transfusion packed RBC and less days of intravenous antibiotics. In both treatment groups, higher numbers of mobilized CD34+ cells were associated with a significantly higher relapse risk irrespective of the treatment given after the mobilization. Randomization between APBSCT and ABMT did not result in significantly different outcomes in terms of DFS, OS and relapse incidence.Bone Marrow Transplantation advance online publication, 17 November 2014; doi:10.1038/bmt.2014.262.
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The IRF5-TNPO3 association with systemic lupus erythematosus has two components that other autoimmune disorders variably share.
Hum. Mol. Genet.
PUBLISHED: 09-08-2014
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Exploiting genotyping, DNA sequencing, imputation and trans-ancestral mapping, we used Bayesian and frequentist approaches to model the IRF5-TNPO3 locus association, now implicated in two immunotherapies and seven autoimmune diseases. Specifically, in systemic lupus erythematosus (SLE), we resolved separate associations in the IRF5 promoter (all ancestries) and with an extended European haplotype. We captured 3230 IRF5-TNPO3 high-quality, common variants across 5 ethnicities in 8395 SLE cases and 7367 controls. The genetic effect from the IRF5 promoter can be explained by any one of four variants in 5.7 kb (P-valuemeta = 6 × 10(-49); OR = 1.38-1.97). The second genetic effect spanned an 85.5-kb, 24-variant haplotype that included the genes IRF5 and TNPO3 (P-valuesEU = 10(-27)-10(-32), OR = 1.7-1.81). Many variants at the IRF5 locus with previously assigned biological function are not members of either final credible set of potential causal variants identified herein. In addition to the known biologically functional variants, we demonstrated that the risk allele of rs4728142, a variant in the promoter among the lowest frequentist probability and highest Bayesian posterior probability, was correlated with IRF5 expression and differentially binds the transcription factor ZBTB3. Our analytical strategy provides a novel framework for future studies aimed at dissecting etiological genetic effects. Finally, both SLE elements of the statistical model appear to operate in Sjögren's syndrome and systemic sclerosis whereas only the IRF5-TNPO3 gene-spanning haplotype is associated with primary biliary cirrhosis, demonstrating the nuance of similarity and difference in autoimmune disease risk mechanisms at IRF5-TNPO3.
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Autosomal dominant immune dysregulation syndrome in humans with CTLA4 mutations.
Nat. Med.
PUBLISHED: 09-01-2014
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The protein cytotoxic T lymphocyte antigen-4 (CTLA-4) is an essential negative regulator of immune responses, and its loss causes fatal autoimmunity in mice. We studied a large family in which five individuals presented with a complex, autosomal dominant immune dysregulation syndrome characterized by hypogammaglobulinemia, recurrent infections and multiple autoimmune clinical features. We identified a heterozygous nonsense mutation in exon 1 of CTLA4. Screening of 71 unrelated patients with comparable clinical phenotypes identified five additional families (nine individuals) with previously undescribed splice site and missense mutations in CTLA4. Clinical penetrance was incomplete (eight adults of a total of 19 genetically proven CTLA4 mutation carriers were considered unaffected). However, CTLA-4 protein expression was decreased in regulatory T cells (Treg cells) in both patients and carriers with CTLA4 mutations. Whereas Treg cells were generally present at elevated numbers in these individuals, their suppressive function, CTLA-4 ligand binding and transendocytosis of CD80 were impaired. Mutations in CTLA4 were also associated with decreased circulating B cell numbers. Taken together, mutations in CTLA4 resulting in CTLA-4 haploinsufficiency or impaired ligand binding result in disrupted T and B cell homeostasis and a complex immune dysregulation syndrome.
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Reproducibility of histopathological diagnosis in poorly differentiated NSCLC: an international multiobserver study.
J Thorac Oncol
PUBLISHED: 08-15-2014
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The 2004 World Health Organization classification of lung cancer contained three major forms of non-small-cell lung cancer: squamous cell carcinoma (SqCC), adenocarcinoma (AdC), and large cell carcinoma. The goal of this study was first, to assess the reproducibility of a set of histopathological features for SqCC in relation to other poorly differentiated non-small-cell lung cancers and second, to assess the value of immunohistochemistry in improving the diagnosis.
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Motivational counseling to reduce sitting time: a community-based randomized controlled trial in adults.
Am J Prev Med
PUBLISHED: 08-08-2014
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Sedentary behavior is regarded as a distinct risk factor for cardiometabolic morbidity and mortality, but knowledge of the efficacy of interventions targeting reductions in sedentary behavior is limited.
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Genetic determinants of circulating interleukin-1 receptor antagonist levels and their association with glycemic traits.
Diabetes
PUBLISHED: 06-26-2014
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The proinflammatory cytokine interleukin (IL)-1? is implicated in the development of insulin resistance and ?-cell dysfunction, whereas higher circulating levels of IL-1 receptor antagonist (IL-1RA), an endogenous inhibitor of IL-1?, has been suggested to improve glycemia and ?-cell function in patients with type 2 diabetes. To elucidate the protective role of IL-1RA, this study aimed to identify genetic determinants of circulating IL-1RA concentration and to investigate their associations with immunological and metabolic variables related to cardiometabolic risk. In the analysis of seven discovery and four replication cohort studies, two single nucleotide polymorphisms (SNPs) were independently associated with circulating IL-1RA concentration (rs4251961 at the IL1RN locus [n = 13,955, P = 2.76 × 10(-21)] and rs6759676, closest gene locus IL1F10 [n = 13,994, P = 1.73 × 10(-17)]). The proportion of the variance in IL-1RA explained by both SNPs combined was 2.0%. IL-1RA-raising alleles of both SNPs were associated with lower circulating C-reactive protein concentration. The IL-1RA-raising allele of rs6759676 was also associated with lower fasting insulin levels and lower HOMA insulin resistance. In conclusion, we show that circulating IL-1RA levels are predicted by two independent SNPs at the IL1RN and IL1F10 loci and that genetically raised IL-1RA may be protective against the development of insulin resistance.
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Molecular packing determines singlet exciton fission in organic semiconductors.
ACS Nano
PUBLISHED: 06-25-2014
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Carrier multiplication by singlet exciton fission enhances photovoltaic conversion efficiencies in organic solids. This decay of one singlet exciton into two triplet states allows the extraction of up to two electrons per harvested photon and, hence, promises to overcome the Shockley–Queisser limit. However, the microscopic mechanism of singlet exciton fission, especially the relation between molecular packing and electronic response, remains unclear, which therefore hampers the systematic improvement of organic photovoltaic devices. For the model system perfluoropentacene, we experimentally show that singlet exciton fission is greatly enhanced for a slip-stacked molecular arrangement by addressing different crystal axes featuring different packing schemes. This reveals that the fission process strongly depends on the intermolecular coupling: slip-stacking favors delocalization of excitations and allows for efficient exciton fission, while face-to-edge molecular orientations commonly found in the prevailing herringbone molecular stacking patterns even suppress it. Furthermore, we clarify the controversially debated role of excimer states as intermediary rather than competitive or precursory. Our detailed findings serve as a guideline for the design of next-generation molecular materials for application in future organic light-harvesting devices exploiting singlet exciton fission.
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Cerebral autoregulation and brain networks in occlusive processes of the internal carotid artery.
J. Cereb. Blood Flow Metab.
PUBLISHED: 06-09-2014
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Patients with unilateral occlusive processes of the internal carotid artery (ICA) show subtle cognitive deficits. Decline in cerebral autoregulation and in functional and structural integrity of brain networks have previously been reported in the affected hemisphere (AH). However, the association between cerebral autoregulation, brain networks, and cognition remains to be elucidated. Fourteen neurologically asymptomatic patients (65±11 years) with either ICA occlusion or high-grade ICA stenosis and 11 age-matched healthy controls (HC) (67±6 years) received neuropsychologic testing, transcranial Doppler sonography to assess cerebral autoregulation using vasomotor reactivity (VMR), and magnetic resonance imaging to probe white matter microstructure and resting-state functional connectivity (RSFC). Patients performed worse on memory and executive tasks when compared with controls. Vasomotor reactivity, white matter microstructure, and RSFC were lower in the AH of the patients when compared with the unaffected hemisphere and with controls. Lower VMR of the AH was associated with several ipsilateral clusters of lower white matter microstructure and lower bilateral RSFC in patients. No correlations were found between VMR and cognitive scores. In sum, impaired cerebral autoregulation was associated with reduced structural and functional connectivity in cerebral networks, indicating possible mechanisms by which severe unilateral occlusive processes of the ICA lead to cognitive decline.Journal of Cerebral Blood Flow & Metabolism advance online publication, 12 November 2014; doi:10.1038/jcbfm.2014.190.
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Crystal and solution structure of the human RIG-I SF2 domain.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 04-16-2014
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RIG-I is a pathogen-recognition receptor that recognizes viral 5'-triphosphates carrying double-stranded RNA. Upon binding to these microbe-associated molecular patterns (MAMPs), RIG-I forms oligomers and promotes downstream processes that result in type I interferon production and induction of an antiviral state. Here, the crystal structure of the human RIG-I superfamily 2 ATPase domain crystallized in an unusually elongated and open conformation is reported. The elongated structure is probably induced in part by crystal packing, but nevertheless indicates that the domain is intrinsically very flexible. This flexibility might allow substantial structural changes upon substrate binding and oligomerization.
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Dendritic cell-mediated immune humanization of mice: implications for allogeneic and xenogeneic stem cell transplantation.
J. Immunol.
PUBLISHED: 04-16-2014
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De novo regeneration of immunity is a major problem after allogeneic hematopoietic stem cell transplantation (HCT). HCT modeling in severely compromised immune-deficient animals transplanted with human stem cells is currently limited because of incomplete maturation of lymphocytes and scarce adaptive responses. Dendritic cells (DC) are pivotal for the organization of lymph nodes and activation of naive T and B cells. Human DC function after HCT could be augmented with adoptively transferred donor-derived DC. In this study, we demonstrate that adoptive transfer of long-lived human DC coexpressing high levels of human IFN-?, human GM-CSF, and a clinically relevant Ag (CMV pp65 protein) promoted human lymphatic remodeling in immune-deficient NOD.Rag1(-/-).IL-2r?(-/-) mice transplanted with human CD34(+) cells. After immunization, draining lymph nodes became replenished with terminally differentiated human follicular Th cells, plasma B cells, and memory helper and cytotoxic T cells. Human Igs against pp65 were detectable in plasma, demonstrating IgG class-switch recombination. Human T cells recovered from mice showed functional reactivity against pp65. Adoptive immunotherapy with engineered DC provides a novel strategy for de novo immune reconstitution after human HCT and a practical and effective tool for studying human lymphatic regeneration in vivo in immune deficient xenograft hosts.
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Development of perceived job insecurity across two years: associations with antecedents and employee outcomes.
J Occup Health Psychol
PUBLISHED: 04-16-2014
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This 2-year longitudinal study among 848 university employees investigated the individual development of perceived job insecurity (JI) in the context of changes occurring in the Finnish universities during the follow-up time. Adopting a person-oriented approach through latent profile analysis, 8 classes of employees with similar mean levels and mean-level changes in JI were identified. Two of these classes (75% of the participants) indicated stable (low, moderately high) JI, and the remaining 6 classes (25% of the participants) showed change (decreasing, increasing, curvilinear) in the level of JI across time. We then examined possible differences between these classes with respect to individual antecedents and outcomes of JI. Of the antecedents, the type of employment contract distinguished best between the JI classes. Of the outcomes, moderately high stable JI was associated with low stable vigor and high stable levels of exhaustion and turnover intentions across time. In addition, it seemed that a decrease in JI was associated with a decrease in exhaustion and turnover intentions and vice versa. Altogether the findings suggest that developmental JI classes exhibit a substantial amount of heterogeneity, which is simultaneously reflected in occupational well-being.
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Clofarabine in combination with a standard remission induction regimen (cytosine arabinoside and idarubicin) in patients with previously untreated intermediate and bad-risk acute myelogenous leukemia (AML) or high-risk myelodysplastic syndrome (HR-MDS): phase I results
Ann. Hematol.
PUBLISHED: 03-10-2014
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This study aims to determine the maximum tolerated dose (MTD) of clofarabine combined with the EORTC-GIMEMA 3?+?10 induction regimen (idarubicin?+?cytosine arabinoside) in adults with untreated acute myelogenous leukemia or high-risk myelodysplastic syndrome. In this phase I trial, 25 patients (median age 56 years) received 5 days of clofarabine as 1-h infusion (arm A) or push injection (arm B) at the dose level of 5?×?10 or 5?×?15 mg/m(2)/day in an algorithmic dose escalation 3?+?3 design. A consolidation course (intermediate dose cytosine arabinoside, idarubicin) was planned for patients in complete remission (CR). Primary endpoint was safety and tolerance as measured by dose limiting toxicity (DLT); secondary endpoints were response rate, other grade III/IV toxicities, and hematological recovery after induction and consolidation. Five DLTs were observed (in arm A: one DLT at 10 mg/m(2)/day, three at 15 mg/m(2)/day; in arm B: one DLT at 15 mg/m(2)/day). Three patients receiving 15 mg/m(2)/day were withdrawn due to adverse events not classified as DLT. Prolonged hypoplasia was observed in five patients. CR?+?complete remission with incomplete recovery were achieved in 21 patients (11/12 (92 %) receiving clofarabine 10 mg/m(2)/day; 10/13 (77 %) receiving clofarabine 15 mg/m(2)/day). Clofarabine, 5?×?10 mg/m(2)/day, resulted in one DLT and no early treatment withdrawals. MTD of clofarabine combined with cytosine arabinoside and idarubicin is 5?×?10 mg/m(2)/day.
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Perceived Control and Psychological Contract Breach as Explanations of the Relationships Between Job Insecurity, Job Strain and Coping Reactions: Towards a Theoretical Integration.
Stress Health
PUBLISHED: 02-27-2014
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This study aims to further knowledge on the mechanisms through which job insecurity is related to negative outcomes. Based on appraisal theory, two explanations-perceived control and psychological contract breach-were theoretically integrated in a comprehensive model and simultaneously examined as mediators of the job insecurity-outcome relationship. Different categories of outcomes were considered, namely work-related (i.e.?vigour and need for recovery) and general strain (i.e.?mental and physical health complaints), as well as psychological (i.e.?job satisfaction and organizational commitment) and behavioural coping reactions (i.e.?self-rated performance and innovative work behaviour). The hypotheses were tested using data of a heterogeneous sample of 2413 Flemish employees by means of both single and multiple mediator structural equation modelling analyses (bootstrapping method). Particularly, psychological contract breach accounted for the relationship between job insecurity and strain. Both perceived control and psychological contract breach mediated the relationships between job insecurity and psychological coping reactions, although the indirect effects were larger for psychological contract breach. Finally, perceived control was more important than psychological contract breach in mediating the relationships between job insecurity and behavioural coping reactions. This study meets previous calls for a theoretical integration regarding mediators of the job insecurity-outcome relationship. Copyright © 2014 John Wiley & Sons, Ltd.
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Lensless phase contrast microscopy based on multiwavelength Fresnel diffraction.
Opt Lett
PUBLISHED: 02-25-2014
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We demonstrate a compact, wide-field, quantitative phase contrast microscope that does not require lenses for image formation. High-resolution images are retrieved from Fresnel diffraction patterns recorded at multiple wavelengths, combined with a robust iterative phase retrieval algorithm. Quantitative phase contrast images of living cultured neurons are obtained with a transverse resolution of <2 ?m. Our system is well suited for high-resolution live cell imaging and provides a compact, cost-effective alternative to full-sized phase-contrast microscopes.
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Lack of replication of higher genetic risk load in men than in women with systemic lupus erythematosus.
Arthritis Res. Ther.
PUBLISHED: 02-21-2014
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We aimed to replicate a recent study which showed higher genetic risk load at 15 loci in men than in women with systemic lupus erythematosus (SLE). This difference was very significant, and it was interpreted as indicating that men require more genetic susceptibility than women to develop SLE.
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Secreted semaphorin 5A activates immune effector cells and is a biomarker for rheumatoid arthritis.
PUBLISHED: 02-11-2014
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To investigate the role of the multifunctional protein semaphorin 5A (Sema5A) in modulating cellular immune responses and as a biomarker in rheumatoid arthritis (RA).
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The inverse BAR domain protein IBARa drives membrane remodeling to control osmoregulation, phagocytosis and cytokinesis.
J. Cell. Sci.
PUBLISHED: 01-24-2014
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Here, we analyzed the single inverse Bin/Amphiphysin/Rvs (I-BAR) family member IBARa from Dictyostelium discoideum. The X-ray structure of the N-terminal I-BAR domain solved at 2.2 Å resolution revealed an all-?-helical structure that self-associates into a 165-Å zeppelin-shaped antiparallel dimer. The structural data are consistent with its shape in solution obtained by small-angle X-ray scattering. Cosedimentation, fluorescence anisotropy, and fluorescence and electron microscopy revealed that the I-BAR domain bound preferentially to phosphoinositide-containing vesicles and drove the formation of negatively curved tubules. Immunofluorescence labeling further showed accumulation of endogenous IBARa at the tips of filopodia, the rim of constricting phagocytic cups, in foci connecting dividing cells during the final stage of cytokinesis and most prominently at the osmoregulatory contractile vacuole (CV). Consistently, IBARa-null mutants displayed defects in CV formation and discharge, growth, phagocytosis and mitotic cell division, whereas filopodia formation was not compromised. Of note, IBARa-null mutants were also strongly impaired in cell spreading. Taken together, these data suggest that IBARa constitutes an important regulator of numerous cellular processes intimately linked with the dynamic rearrangement of cellular membranes.
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Analysis of the near-edge X-ray-absorption fine-structure of anthracene: a combined theoretical and experimental study.
J Chem Phys
PUBLISHED: 01-14-2014
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The near-edge fine structure of the carbon K-edge absorption spectrum of anthracene was measured and theoretically analyzed by density functional theory calculations implemented in the StoBe code. It is demonstrated that the consideration of electronic relaxation of excited states around localized core holes yields a significant improvement of the calculated excitation energies and reproduces the experimentally observed fine structure well. The detailed analysis of excitation spectra calculated for each symmetry inequivalent excitation center allows in particular to examine the influence of chemical shifts and core hole effects on the excitation energies. Moreover, the visualization of final states explains the large variations in the oscillator strength of various transitions as well as the nature of Rydberg-states that exhibit a notable density of states below the ionization potentials.
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A genome-wide association study follow-up suggests a possible role for PPARG in systemic sclerosis susceptibility.
Arthritis Res. Ther.
PUBLISHED: 01-09-2014
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A recent genome-wide association study (GWAS) comprising a French cohort of systemic sclerosis (SSc) reported several non-HLA single-nucleotide polymorphisms (SNPs) showing a nominal association in the discovery phase. We aimed to identify previously overlooked susceptibility variants by using a follow-up strategy.
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Immunochip analysis identifies multiple susceptibility loci for systemic sclerosis.
Am. J. Hum. Genet.
PUBLISHED: 01-07-2014
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In this study, 1,833 systemic sclerosis (SSc) cases and 3,466 controls were genotyped with the Immunochip array. Classical alleles, amino acid residues, and SNPs across the human leukocyte antigen (HLA) region were imputed and tested. These analyses resulted in a model composed of six polymorphic amino acid positions and seven SNPs that explained the observed significant associations in the region. In addition, a replication step comprising 4,017 SSc cases and 5,935 controls was carried out for several selected non-HLA variants, reaching a total of 5,850 cases and 9,401 controls of European ancestry. Following this strategy, we identified and validated three SSc risk loci, including DNASE1L3 at 3p14, the SCHIP1-IL12A locus at 3q25, and ATG5 at 6q21, as well as a suggested association of the TREH-DDX6 locus at 11q23. The associations of several previously reported SSc risk loci were validated and further refined, and the observed peak of association in PXK was related to DNASE1L3. Our study has increased the number of known genetic associations with SSc, provided further insight into the pleiotropic effects of shared autoimmune risk factors, and highlighted the power of dense mapping for detecting previously overlooked susceptibility loci.
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Optimized ratiometric calcium sensors for functional in vivo imaging of neurons and T lymphocytes.
Nat. Methods
PUBLISHED: 01-05-2014
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The quality of genetically encoded calcium indicators (GECIs) has improved dramatically in recent years, but high-performing ratiometric indicators are still rare. Here we describe a series of fluorescence resonance energy transfer (FRET)-based calcium biosensors with a reduced number of calcium binding sites per sensor. These 'Twitch' sensors are based on the C-terminal domain of Opsanus troponin C. Their FRET responses were optimized by a large-scale functional screen in bacterial colonies, refined by a secondary screen in rat hippocampal neuron cultures. We tested the in vivo performance of the most sensitive variants in the brain and lymph nodes of mice. The sensitivity of the Twitch sensors matched that of synthetic calcium dyes and allowed visualization of tonic action potential firing in neurons and high resolution functional tracking of T lymphocytes. Given their ratiometric readout, their brightness, large dynamic range and linear response properties, Twitch sensors represent versatile tools for neuroscience and immunology.
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A Candidate Gene Approach Identifies an IL33 Genetic Variant as a Novel Genetic Risk Factor for GCA.
PLoS ONE
PUBLISHED: 01-01-2014
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Increased expression of IL-33 and its receptor ST2, encoded by the IL1RL1 gene, has been detected in the inflamed arteries of giant cell arteritis (GCA) patients. The aim of the present study was to investigate for the first time the potential influence of the IL33 and IL1RL1 loci on GCA predisposition.
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Increased HEV seroprevalence in patients with autoimmune hepatitis.
PLoS ONE
PUBLISHED: 01-01-2014
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Hepatitis E virus (HEV) infection takes a clinically silent, self-limited course in the far majority of cases. Chronic hepatitis E has been reported in some cohorts of immunocompromised individuals. The role of HEV infections in patients with autoimmune hepatitis (AIH) is unknown.
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Structural model for the covalent adhesion of the Streptococcus pyogenes pilus through a thioester bond.
J. Biol. Chem.
PUBLISHED: 11-12-2013
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The human pathogen Streptococcus pyogenes produces pili that are essential for adhesion to host surface receptors. Cpa, the adhesin at the pilus tip, was recently shown to have a thioester-containing domain. The thioester bond is believed to be important in adhesion, implying a mechanism of covalent attachment analogous to that used by human complement factors. Here, we characterize a second active thioester-containing domain on Cpa, termed CpaN. Expression of CpaN in E. coli gave covalently-linked dimers. These were shown by X-ray crystallography and mass spectrometry to comprise two CpaN molecules crosslinked by the polyamine spermidine, following reaction with the thioester bonds. This cross-linked CpaN dimer provides a model for the covalent attachment of Cpa to target receptors and thus the streptococcal pilus to host cells. Similar thioester domains were identified in cell-wall proteins of other Gram-positive pathogens, suggesting that thioester domains are more widely used and provide a mechanism of adhesion, by covalent bonding to target molecules on host cells, that mimics that used by the human complement system to eliminate pathogens.
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International recommendations for the assessment of autoantibodies to cellular antigens referred to as anti-nuclear antibodies.
Ann. Rheum. Dis.
PUBLISHED: 10-14-2013
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Anti-nuclear antibodies (ANA) are fundamental for the diagnosis of autoimmune diseases, and have been determined by indirect immunofluorescence assay (IIFA) for decades. As the demand for ANA testing increased, alternative techniques were developed challenging the classic IIFA. These alternative platforms differ in their antigen profiles, sensitivity and specificity, raising uncertainties regarding standardisation and interpretation of incongruent results. Therefore, an international group of experts has created recommendations for ANA testing by different methods. Two groups of experts participated in this initiative. The European autoimmunity standardization initiative representing 15 European countries and the International Union of Immunologic Societies/World Health Organization/Arthritis Foundation/Centers for Disease Control and Prevention autoantibody standardising committee. A three-step process followed by a Delphi exercise with closed voting was applied. Twenty-five recommendations for determining ANA (1-13), anti-double stranded DNA antibodies (14-18), specific antibodies (19-23) and validation of methods (24-25) were created. Significant differences between experts were observed regarding recommendations 24-25 (p<0.03). Here, we formulated recommendations for the assessment and interpretation of ANA and associated antibodies. Notably, the roles of IIFA as a reference method, and the importance of defining nuclear and cytoplasmic staining, were emphasised, while the need to incorporate alternative automated methods was acknowledged. Various approaches to overcome discrepancies between methods were suggested of which an improved bench-to-bedside communication is of the utmost importance. These recommendations are based on current knowledge and can enable harmonisation of local algorithms for testing and evaluation of ANA and related autoantibodies. Last but not least, new more appropriate terminologies have been suggested.
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High-energy, high-repetition-rate picosecond pulses from a quasi-CW diode-pumped Nd:YAG system.
Opt Lett
PUBLISHED: 10-10-2013
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We report on a high-power quasi-CW pumped Nd:YAG laser system, producing 130 mJ, 64 ps pulses at 1064 nm wavelength with a repetition rate of 300 Hz. Pulses from a Nd:YVO(4) oscillator are first amplified by a regenerative amplifier to the millijoule level and then further amplified in quasi-CW diode-pumped Nd:YAG modules. Pulsed diode pumping enables a high gain at repetition rates of several hundred hertz, while keeping thermal effects manageable. Birefringence compensation and multiple thermal-lensing-compensated relay-imaging stages are used to maintain a top-hat beam profile. After frequency doubling, 75 mJ pulses are obtained at 532 nm. The intensity stability is better than 1.1%, which makes this laser an attractive pump source for a high-repetition-rate optical parametric amplification system.
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Cell-imprinted substrates direct the fate of stem cells.
ACS Nano
PUBLISHED: 10-01-2013
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Smart nanoenvironments were obtained by cell-imprinted substrates based on mature and dedifferentiated chondrocytes as templates. Rabbit adipose derived mesenchymal stem cells (ADSCs) seeded on these cell-imprinted substrates were driven to adopt the specific shape (as determined in terms of cell morphology) and molecular characteristics (as determined in terms of gene expression) of the cell types which had been used as template for the cell-imprinting. This method might pave the way for a reliable, efficient, and cheap way of controlling stem cell differentiation. Data also suggest that besides residual cellular fragments, which are presented on the template surface, the imprinted topography of the templates plays a role in the differentiation of the stem cells.
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Diffusion-controlled growth of molecular heterostructures: fabrication of two-, one-, and zero-dimensional C(60) nanostructures on pentacene substrates.
ACS Appl Mater Interfaces
PUBLISHED: 09-19-2013
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A variety of low dimensional C60 structures has been grown on supporting pentacene multilayers. By choice of substrate temperature during growth the effective diffusion length of evaporated fullerenes and their nucleation at terraces or step edges can be precisely controlled. AFM and SEM measurements show that this enables the fabrication of either 2D adlayers or solely 1D chains decorating substrate steps, while at elevated growth temperature continuous wetting of step edges is prohibited and instead the formation of separated C60 clusters pinned at the pentacene step edges occurs. Remarkably, all structures remain thermally stable at room temperature once they are formed. In addition the various fullerene structures have been overgrown by an additional pentacene capping layer. Utilizing the different probe depth of XRD and NEXAFS, we found that no contiguous pentacene film is formed on the 2D C60 structure, whereas an encapsulation of the 1D and 0D structures with uniformly upright oriented pentacene is achieved, hence allowing the fabrication of low dimensional buried organic heterostructures.
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Magnetic resonance imaging in the evaluation of patients with sensorineural hearing loss caused by meningitis: implications for cochlear implantation.
Otol. Neurotol.
PUBLISHED: 06-18-2013
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To determine the role of MRI in the evaluation of patients with sensorineural hearing loss (SNHL) caused by meningitis. Gadolinium-enhanced T1-weighted MRI (GdMRI) and 3D heavily weighted T2-weighted MRI (T2MRI) were associated with the occurrence of SNHL and the peroperative surgical findings during cochlear implantation, respectively.
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Combined heart rate- and accelerometer-assessed physical activity energy expenditure and associations with glucose homeostasis markers in a population at high risk of developing diabetes: the ADDITION-PRO study.
Diabetes Care
PUBLISHED: 06-11-2013
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Regular physical activity (PA) reduces the risk of developing type 2 diabetes, and different subtypes of dysglycemia have shown different associations with PA. To better understand the associations of PA and glucose homeostasis, we examined the association of objectively measured PA energy expenditure (PAEE) with detailed measures of glucose homeostasis.
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A systemic sclerosis and systemic lupus erythematosus pan-meta-GWAS reveals new shared susceptibility loci.
Hum. Mol. Genet.
PUBLISHED: 06-04-2013
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Systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) are two archetypal systemic autoimmune diseases which have been shown to share multiple genetic susceptibility loci. In order to gain insight into the genetic basis of these diseases, we performed a pan-meta-analysis of two genome-wide association studies (GWASs) together with a replication stage including additional SSc and SLE cohorts. This increased the sample size to a total of 21,109 (6835 cases and 14,274 controls). We selected for replication 19 SNPs from the GWAS data. We were able to validate KIAA0319L (P = 3.31 × 10(-11), OR = 1.49) as novel susceptibility loci for SSc and SLE. Furthermore, we also determined that the previously described SLE susceptibility loci PXK (P = 3.27 × 10(-11), OR = 1.20) and JAZF1 (P = 1.11 × 10(-8), OR = 1.13) are shared with SSc. Supporting these new discoveries, we observed that KIAA0319L was overexpressed in peripheral blood cells of SSc and SLE patients compared with healthy controls. With these, we add three (KIAA0319L, PXK and JAZF1) and one (KIAA0319L) new susceptibility loci for SSc and SLE, respectively, increasing significantly the knowledge of the genetic basis of autoimmunity.
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Risk factors associated with cast complications in horses: 398 cases (1997-2006).
J. Am. Vet. Med. Assoc.
PUBLISHED: 05-31-2013
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To determine the frequency of and risk factors for complications associated with casts in horses.
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Variants at multiple loci implicated in both innate and adaptive immune responses are associated with Sjögrens syndrome.
Nat. Genet.
PUBLISHED: 04-27-2013
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Sjögrens syndrome is a common autoimmune disease (affecting ?0.7% of European Americans) that typically presents as keratoconjunctivitis sicca and xerostomia. Here we report results of a large-scale association study of Sjögrens syndrome. In addition to strong association within the human leukocyte antigen (HLA) region at 6p21 (Pmeta = 7.65 × 10(-114)), we establish associations with IRF5-TNPO3 (Pmeta = 2.73 × 10(-19)), STAT4 (Pmeta = 6.80 × 10(-15)), IL12A (Pmeta = 1.17 × 10(-10)), FAM167A-BLK (Pmeta = 4.97 × 10(-10)), DDX6-CXCR5 (Pmeta = 1.10 × 10(-8)) and TNIP1 (Pmeta = 3.30 × 10(-8)). We also observed suggestive associations (Pmeta < 5 × 10(-5)) with variants in 29 other regions, including TNFAIP3, PTTG1, PRDM1, DGKQ, FCGR2A, IRAK1BP1, ITSN2 and PHIP, among others. These results highlight the importance of genes that are involved in both innate and adaptive immunity in Sjögrens syndrome.
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cGAS produces a 2-5-linked cyclic dinucleotide second messenger that activates STING.
Nature
PUBLISHED: 04-01-2013
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Detection of cytoplasmic DNA represents one of the most fundamental mechanisms of the innate immune system to sense the presence of microbial pathogens. Moreover, erroneous detection of endogenous DNA by the same sensing mechanisms has an important pathophysiological role in certain sterile inflammatory conditions. The endoplasmic-reticulum-resident protein STING is critically required for the initiation of type I interferon signalling upon detection of cytosolic DNA of both exogenous and endogenous origin. Next to its pivotal role in DNA sensing, STING also serves as a direct receptor for the detection of cyclic dinucleotides, which function as second messenger molecules in bacteria. DNA recognition, however, is triggered in an indirect fashion that depends on a recently characterized cytoplasmic nucleotidyl transferase, termed cGAMP synthase (cGAS), which upon interaction with DNA synthesizes a dinucleotide molecule that in turn binds to and activates STING. We here show in vivo and in vitro that the cGAS-catalysed reaction product is distinct from previously characterized cyclic dinucleotides. Using a combinatorial approach based on mass spectrometry, enzymatic digestion, NMR analysis and chemical synthesis we demonstrate that cGAS produces a cyclic GMP-AMP dinucleotide, which comprises a 2-5 and a 3-5 phosphodiester linkage >Gp(2-5)Ap(3-5)>. We found that the presence of this 2-5 linkage was required to exert potent activation of human STING. Moreover, we show that cGAS first catalyses the synthesis of a linear 2-5-linked dinucleotide, which is then subject to cGAS-dependent cyclization in a second step through a 3-5 phosphodiester linkage. This 13-membered ring structure defines a novel class of second messenger molecules, extending the family of 2-5-linked antiviral biomolecules.
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Thermally activated intermixture in pentacene-perfluoropentacene heterostructures.
J Chem Phys
PUBLISHED: 03-29-2013
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Using thermal desorption spectroscopy (TDS) the thermal stability of binary pentacene/perfluoropentacene (PEN/PFP) thin films has been investigated for various preparation protocols. Variation of stoichiometry ratio reveals a significantly enhanced thermal stability in comparison to the single compounds only for films with equimolar stoichiometry. The stabilization also depends on the preparation method and was found for co-deposition as well as for multi-stacks and subsequently grown PEN/PFP-stacks but not for stacks grown in the reversed order. By systemically varying the substrate temperature during deposition, we prove that the resulting intermixture is caused by a thermally activated diffusion during film growth and not due to post-deposition diffusion induced upon heating during TDS measurements. The different extents of thermal stabilization are discussed in the context of the film morphology studied by means of atomic force microscopy (AFM). For complementary information, optical absorption spectra of the heterostructures are analyzed, where the arisal of new absorption bands and the extinction of excitonic bands existing in the pure compounds are identified as decisive criteria to judge the efficiency of intermixture.
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High-precision spectroscopy with counterpropagating femtosecond pulses.
Phys. Rev. Lett.
PUBLISHED: 03-28-2013
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An experimental realization of high-precision direct frequency comb spectroscopy using counterpropagating femtosecond pulses on two-photon atomic transitions is presented. The Doppler broadened background signal, hampering precision spectroscopy with ultrashort pulses, is effectively eliminated with a simple pulse shaping method. As a result, all four 5S-7S two-photon transitions in a rubidium vapor are determined with both statistical and systematic uncertainties below 10(-11), which is an order of magnitude better than previous experiments on these transitions.
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Structural mechanism of cytosolic DNA sensing by cGAS.
Nature
PUBLISHED: 03-21-2013
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Cytosolic DNA arising from intracellular bacterial or viral infections is a powerful pathogen-associated molecular pattern (PAMP) that leads to innate immune host defence by the production of type I interferon and inflammatory cytokines. Recognition of cytosolic DNA by the recently discovered cyclic-GMP-AMP (cGAMP) synthase (cGAS) induces the production of cGAMP to activate the stimulator of interferon genes (STING). Here we report the crystal structure of cGAS alone and in complex with DNA, ATP and GTP along with functional studies. Our results explain the broad DNA sensing specificity of cGAS, show how cGAS catalyses dinucleotide formation and indicate activation by a DNA-induced structural switch. cGAS possesses a remarkable structural similarity to the antiviral cytosolic double-stranded RNA sensor 2-5oligoadenylate synthase (OAS1), but contains a unique zinc thumb that recognizes B-form double-stranded DNA. Our results mechanistically unify dsRNA and dsDNA innate immune sensing by OAS1 and cGAS nucleotidyl transferases.
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Prophylaxis and treatment of GVHD: EBMT-ELN working group recommendations for a standardized practice.
Bone Marrow Transplant.
PUBLISHED: 03-06-2013
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GVHD remains the major impediment to broader application of allogeneic haematopoietic SCT. It can be prevented completely, but at the expense of other complications, rejection, relapse or delayed immune reconstitution. No optimal prevention or treatment method has been defined. This is reflected by enormous heterogeneity in approaches in Europe. Retrospective comparisons between different policies, although warranted, do not give definite answers. In order to improve the present situation, an European Group for Blood and Marrow Transplantation and the European LeukemiaNet working group has developed in a Delphi-like approach recommendations for prophylaxis and treatment of GVHD in the most common allogeneic transplant setting, transplantation from an HLA-identical sibling or unrelated donor for standard risk malignant disease. The working group proposes these guidelines to be adopted as routine standard in transplantation centres and to be used as comparator in systematic studies evaluating the advantages and disadvantages of practices differing from these recommendations.Bone Marrow Transplantation advance online publication, 29 July 2013; doi:10.1038/bmt.2013.107.
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New insight on the Xq28 association with systemic sclerosis.
Ann. Rheum. Dis.
PUBLISHED: 02-26-2013
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To evaluate whether the systemic sclerosis (SSc)-associated IRAK1 non-synonymous single-nucleotide polymorphism rs1059702 is responsible for the Xq28 association with SSc or whether there are other independent signals in the nearby methyl-CpG-binding protein 2 gene (MECP2).
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Studies of association of AGPAT6 variants with type 2 diabetes and related metabolic phenotypes in 12,068 Danes.
BMC Med. Genet.
PUBLISHED: 02-18-2013
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Type 2 diabetes, obesity and insulin resistance are characterized by hypertriglyceridemia and ectopic accumulation of lipids in liver and skeletal muscle. AGPAT6 encodes a novel glycerol-3 phosphate acyltransferase, GPAT4, which catalyzes the first step in the de novo triglyceride synthesis. AGPAT6-deficient mice show lower weight and resistance to diet- and genetically induced obesity. Here, we examined whether common or low-frequency variants in AGPAT6 associate with type 2 diabetes or related metabolic traits in a Danish population.
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Reduced intensity-conditioned allogeneic stem cell transplantation for multiple myeloma relapsing or progressing after autologous transplantation: a study by the European Group for Blood and Marrow Transplantation.
Bone Marrow Transplant.
PUBLISHED: 01-30-2013
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Outcomes and prognostic factors of reduced intensity-conditioned allo-SCT (RIC allo-SCT) for multiple myeloma (MM) relapsing or progressing after prior autologous (auto)-SCT are not well defined. We performed an analysis of 413 MM patients who received a related or unrelated RIC allo-SCT for the treatment of relapse/progression after prior auto-SCT. Median age at RIC allo-SCT was 54.1 years, and 44.6% of patients had undergone two or more prior auto-SCTs. Median OS and PFS from the time of RIC allo-SCT for the entire population were 24.7 and 9.6 months, respectively. Cumulative non-relapse mortality (NRM) at 1 year was 21.5%. In multivariate analysis, CMV seronegativity of both patient and donor was associated with significantly better PFS, OS and NRM. Patient-donor gender mismatch was associated with better PFS, fewer than two prior auto-SCT was associated with better OS, and shorter time from the first auto-SCT to the RIC allo-SCT was associated with lower NRM. The results of this study identify patient and donor CMV seronegativity as the key prognostic factor for outcome after RIC allo-SCT for MM relapsing or progressing after prior auto-SCT.
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The systemic lupus erythematosus IRF5 risk haplotype is associated with systemic sclerosis.
PLoS ONE
PUBLISHED: 01-23-2013
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Systemic sclerosis (SSc) is a fibrotic autoimmune disease in which the genetic component plays an important role. One of the strongest SSc association signals outside the human leukocyte antigen (HLA) region corresponds to interferon (IFN) regulatory factor 5 (IRF5), a major regulator of the type I IFN pathway. In this study we aimed to evaluate whether three different haplotypic blocks within this locus, which have been shown to alter the protein function influencing systemic lupus erythematosus (SLE) susceptibility, are involved in SSc susceptibility and clinical phenotypes. For that purpose, we genotyped one representative single-nucleotide polymorphism (SNP) of each block (rs10488631, rs2004640, and rs4728142) in a total of 3,361 SSc patients and 4,012 unaffected controls of Caucasian origin from Spain, Germany, The Netherlands, Italy and United Kingdom. A meta-analysis of the allele frequencies was performed to analyse the overall effect of these IRF5 genetic variants on SSc. Allelic combination and dependency tests were also carried out. The three SNPs showed strong associations with the global disease (rs4728142: P ?=?1.34×10(-8), OR ?=?1.22, CI 95% ?=?1.14-1.30; rs2004640: P ?=?4.60×10(-7), OR ?=?0.84, CI 95% ?=?0.78-0.90; rs10488631: P ?=?7.53×10(-20), OR ?=?1.63, CI 95% ?=?1.47-1.81). However, the association of rs2004640 with SSc was not independent of rs4728142 (conditioned P ?=?0.598). The haplotype containing the risk alleles (rs4728142*A-rs2004640*T-rs10488631*C: P ?=?9.04×10(-22), OR ?=?1.75, CI 95% ?=?1.56-1.97) better explained the observed association (likelihood P-value ?=?1.48×10(-4)), suggesting an additive effect of the three haplotypic blocks. No statistical significance was observed in the comparisons amongst SSc patients with and without the main clinical characteristics. Our data clearly indicate that the SLE risk haplotype also influences SSc predisposition, and that this association is not sub-phenotype-specific.
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Paramyxovirus V proteins disrupt the fold of the RNA sensor MDA5 to inhibit antiviral signaling.
Science
PUBLISHED: 01-17-2013
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The retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) melanoma differentiation-associated protein 5 (MDA5) senses cytoplasmic viral RNA and activates antiviral innate immunity. To reveal how paramyxoviruses counteract this response, we determined the crystal structure of the MDA5 adenosine 5-triphosphate (ATP)-hydrolysis domain in complex with the viral inhibitor V protein. The V protein unfolded the ATP-hydrolysis domain of MDA5 via a ?-hairpin motif and recognized a structural motif of MDA5 that is normally buried in the conserved helicase fold. This leads to disruption of the MDA5 ATP-hydrolysis site and prevention of RNA-bound MDA5 filament formation. The structure explains why V proteins inactivate MDA5, but not RIG-I, and mutating only two amino acids in RIG-I induces robust V protein binding. Our results suggest an inhibition mechanism of RLR signalosome formation by unfolding of receptor and inhibitor.
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Association of the LILRA3 Deletion with B-NHL and Functional Characterization of the Immunostimulatory Molecule.
PLoS ONE
PUBLISHED: 01-01-2013
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LILRA3 is the sole soluble member of the LILR family. Previous studies from our group had shown that a 6.7 kb genetic deletion of LILRA3 is associated with MS and Sjögrens syndrome. An impairment of the immune response leads to a predisposition for B-NHL, so we wanted to study whether the deletion of LILRA3 is also a risk factor for B-NHL, as well as the function of LILRA3. We discovered that the frequency of the homozygous LILRA3 deletion was significantly higher in B-NHL (6%) than in blood donors (3%) (P?=?0.03). We detected binding of fluorochrome-conjugated recombinant LILRA3 to monocytes and B-cells. Incubation of PBMCs with recombinant LILRA3 induced proliferation of CD8(+) T-cells and NK cells, as determined by CFSE staining. Using a transwell system, we demonstrated that LILRA3-stimulated lymphocyte proliferation was mediated by monocytes and required both cell contact and soluble factors. Secretion of IL-6, IL-8, IL-1? and IL-10 in the cell supernatant was stimulated by LILRA3. We conclude that LILRA3 is an immunostimulatory molecule, whose deficiency is associated with higher frequency of B-NHL.
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Was lates late? A null model for the nile perch boom in lake victoria.
PLoS ONE
PUBLISHED: 01-01-2013
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Nile perch (Lates niloticus) suddenly invaded Lake Victoria between 1979 and 1987, 25 years after its introduction in the Ugandan side of the lake. Nile perch then replaced the native fish diversity and irreversibly altered the ecosystem and its role to lakeshore societies: it is now a prised export product that supports millions of livelihoods. The delay in the Nile perch boom led to a hunt for triggers of the sudden boom and generated several hypotheses regarding its growth at low abundances - all hypotheses having important implications for the management of Nile perch stocks. We use logistic growth as a parsimonious null model to predict when the Nile perch invasion should have been expected, given its growth rate, initial stock size and introduction year. We find the first exponential growth phase can explain the timing of the perch boom at the scale of Lake Victoria, suggesting that complex mechanisms are not necessary to explain the Nile perch invasion or its timing. However, the boom started in Kenya before Uganda, indicating perhaps that Allee effects act at smaller scales than that of the whole Lake. The Nile perch invasion of other lakes indicates that habitat differences may also have an effect on invasion success. Our results suggest there is probably no single management strategy applicable to the whole lake that would lead to both efficient and sustainable exploitation of its resources.
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A standardized vascular disease health check in europe: a cost-effectiveness analysis.
PLoS ONE
PUBLISHED: 01-01-2013
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No clinical trials have assessed the effects or cost-effectiveness of health check strategies to detect and manage vascular disease. We used a mathematical model to estimate the cost-effectiveness of several health check strategies in six European countries.
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Association of CD247 polymorphisms with rheumatoid arthritis: a replication study and a meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2013
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Given the role of CD247 in the response of the T cells, its entailment in autoimmune diseases and in order to better clarify the role of this gene in RA susceptibility, we aimed to analyze CD247 gene variants previously associated with other autoimmune diseases (rs1052237, rs2056626 and rs864537) in a large independent European Caucasian population. However, no evidence of association was found for the analyzed CD247 single-nucleotide polymorphisms (SNPs) with RA and with the presence/absence of anti-cyclic citrullinated polypeptide. We performed a meta-analysis including previously published GWAS data from the rs864537 variant, revealing an overall genome-wide significant association between this CD247 SNP and RA with anti-CCP (OR?=?0.90, CI 95%?=?0.87-0.93, Poverall?=?2.1×10(-10)). Our results show for first time a GWAS-level association between this CD247 polymorphism and RA risk.
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Identification of the tyrosine-protein phosphatase non-receptor type 2 as a rheumatoid arthritis susceptibility locus in europeans.
PLoS ONE
PUBLISHED: 01-01-2013
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Genome-wide association studies have facilitated the identification of over 30 susceptibility loci for rheumatoid arthritis (RA). However, evidence for a number of potential susceptibility genes have not so far reached genome-wide significance in studies of Caucasian RA.
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Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania.
Zookeys
PUBLISHED: 01-01-2013
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Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania, are described and illustrated. These species closely resemble each other. Their affinities to other zooplanktivorous haplochromines from Lake Victoria are discussed. Haplochromis argens sp. n., which featured under nicknames (mainly Haplochromis "argens") in more than 50 papers, was caught both in the Mwanza Gulf and the Emin Pasha Gulf, whereas Haplochromis goldschmidti sp. n. was only found in the Emin Pasha Gulf. Of the latter species only males are available, but it seems unlikely that it represents a case of male colour polymorphism as several presumably unrelated characters differ in sympatry between the two species, suggesting that there is no gene flow. Statistical analysis revealed that the overall difference between the two species is greater than that between the populations from the two locations. Body depth of the two species in sympatry in the Emin Pasha Gulf was more similar than that of Haplochromis goldschmidti sp. n. and the allopatric population of Haplochromis argens sp. n. from the Mwanza Gulf,which mayindicate an overall environmental effect. However, several measurements related to the width of snout and mouth differed more between the populations of the two species in sympatry than between the allopatric populations. In contrast to a group of zooplanktivorous species that recovered successfully after environmental changes in the lake, Haplochromis argens sp. n. is among a group that became extremely rare and probably is in danger of extinction; the conservation status of Haplochromis goldschmidti sp. n. is currently unknown.
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QTc interval prolongation is independently associated with severe hypoglycemic attacks in type 1 diabetes from the EURODIAB IDDM complications study.
Diabetes Care
PUBLISHED: 11-28-2011
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Our aim was to assess whether severe hypoglycemic attacks were cross-sectionally associated with abnormalities of the QTc interval in type 1 diabetic patients.
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Hematopoietic stem cell transplantation in T-prolymphocytic leukemia: a retrospective study from the European Group for Blood and Marrow Transplantation and the Royal Marsden Consortium.
Leukemia
PUBLISHED: 11-25-2011
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T-prolymphocytic leukemia (T-PLL) has a very poor prognosis with conventional immunochemotherapy. Incidental reports suggest that allogeneic hematopoietic stem cell transplantation (allo-HSCT) might have a role in this disease. Therefore, the purpose of the present study was to analyze the outcome of transplants for T-PLL registered with the European Group for Blood and Marrow Transplantation database and the Royal Marsden Consortium. Eligible were 41 patients with a median age of 51 (24-71) years; median time from diagnosis to treatment was 12 months, and in complete remission (CR) (11), partial remission (PR) (12), stable or progressive disease (13) and unknown in 5 patients. A total of 13 patients (31%) received reduced-intensity conditioning. Donors were HLA-identical siblings in 21 patients, matched unrelated donors in 20 patients. With a median follow-up of surviving patients of 36 months, 3-year relapse-free survival (RFS) and OS was 19% (95% CI, 6-31%) and 21% (95% CI, 7-34%), respectively. Multivariate analysis identified TBI and a short interval between diagnosis and HSCT as factors associated with favorable RFS. Three-year non relapse mortality and relapse incidence were each 41% with the majority of relapses occurring within the first year. These data indicate that allo-HSCT may provide effective disease control in selected patients with T-PLL.
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Immobilization of quantum dots via conjugated self-assembled monolayers and their application as a light-controlled sensor for the detection of hydrogen peroxide.
ACS Nano
PUBLISHED: 11-18-2011
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A light-addressable gold electrode modified with CdS and FePt or with CdS@FePt nanoparticles via an interfacial dithiol linker layer is presented. XPS measurements reveal that trans-stilbenedithiol provides high-quality self-assembled monolayers compared to benzenedithiol and biphenyldithiol, in case they are formed at elevated temperatures. The CdS nanoparticles in good electrical contact with the electrode allow for current generation under illumination and appropriate polarization. FePt nanoparticles serve as catalytic sites for the reduction of hydrogen peroxide to water. Advantageously, both properties can be combined by the use of hybrid nanoparticles fixed on the electrode by means of the optimized stilbenedithiol layer. This allows a light-controlled analysis of different hydrogen peroxide concentrations.
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A GWAS follow-up study reveals the association of the IL12RB2 gene with systemic sclerosis in Caucasian populations.
Hum. Mol. Genet.
PUBLISHED: 11-10-2011
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A single-nucleotide polymorphism (SNP) at the IL12RB2 locus showed a suggestive association signal in a previously published genome-wide association study (GWAS) in systemic sclerosis (SSc). Aiming to reveal the possible implication of the IL12RB2 gene in SSc, we conducted a follow-up study of this locus in different Caucasian cohorts. We analyzed 10 GWAS-genotyped SNPs in the IL12RB2 region (2309 SSc patients and 5161 controls). We then selected three SNPs (rs3790567, rs3790566 and rs924080) based on their significance level in the GWAS, for follow-up in an independent European cohort comprising 3344 SSc and 3848 controls. The most-associated SNP (rs3790567) was further tested in an independent cohort comprising 597 SSc patients and 1139 controls from the USA. After conditional logistic regression analysis of the GWAS data, we selected rs3790567 [P(MH)= 1.92 × 10(-5) odds ratio (OR) = 1.19] as the genetic variant with the firmest independent association observed in the analyzed GWAS peak of association. After the first follow-up phase, only the association of rs3790567 was consistent (P(MH)= 4.84 × 10(-3) OR = 1.12). The second follow-up phase confirmed this finding (P(?2) = 2.82 × 10(-4) OR = 1.34). After performing overall pooled-analysis of all the cohorts included in the present study, the association found for the rs3790567 SNP in the IL12RB2 gene region reached GWAS-level significant association (P(MH)= 2.82 × 10(-9) OR = 1.17). Our data clearly support the IL12RB2 genetic association with SSc, and suggest a relevant role of the interleukin 12 signaling pathway in SSc pathogenesis.
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Genetic and physical interaction of the B-cell systemic lupus erythematosus-associated genes BANK1 and BLK.
Ann. Rheum. Dis.
PUBLISHED: 10-06-2011
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Altered signalling in B cells is a predominant feature of systemic lupus erythematosus (SLE). The genes BANK1 and BLK were recently described as associated with SLE. BANK1 codes for a B-cell-specific cytoplasmic protein involved in B-cell receptor signalling and BLK codes for an Src tyrosine kinase with important roles in B-cell development. To characterise the role of BANK1 and BLK in SLE, a genetic interaction analysis was performed hypothesising that genetic interactions could reveal functional pathways relevant to disease pathogenesis.
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Molecular basis of Rrn3-regulated RNA polymerase I initiation and cell growth.
Genes Dev.
PUBLISHED: 09-22-2011
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Cell growth is regulated during RNA polymerase (Pol) I transcription initiation by the conserved factor Rrn3/TIF-IA in yeast/humans. Here we provide a structure-function analysis of Rrn3 based on a combination of structural biology with in vivo and in vitro functional assays. The Rrn3 crystal structure reveals a unique HEAT repeat fold and a surface serine patch. Phosphorylation of this patch represses human Pol I transcription, and a phospho-mimetic patch mutation prevents Rrn3 binding to Pol I in vitro and reduces cell growth and Pol I gene occupancy in vivo. Cross-linking indicates that Rrn3 binds Pol I between its subcomplexes, AC40/19 and A14/43, which faces the serine patch. The corresponding region of Pol II binds the Mediator head that cooperates with transcription factor (TF) IIB. Consistent with this, the Rrn3-binding factor Rrn7 is predicted to be a TFIIB homolog. This reveals the molecular basis of Rrn3-regulated Pol I initiation and cell growth, and indicates a general architecture of eukaryotic transcription initiation complexes.
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Association of systemic lupus erythematosus clinical features with European population genetic substructure.
PLoS ONE
PUBLISHED: 09-08-2011
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Systemic Lupus Erythematosus (SLE) is an autoimmune disease with a very varied spectrum of clinical manifestations that could be partly determined by genetic factors. We aimed to determine the relationship between prevalence of 11 clinical features and age of disease onset with European population genetic substructure. Data from 1413 patients of European ancestry recruited in nine countries was tested for association with genotypes of top ancestry informative markers. This analysis was done with logistic regression between phenotypes and genotypes or principal components extracted from them. We used a genetic additive model and adjusted for gender and disease duration. Three clinical features showed association with ancestry informative markers: autoantibody production defined as immunologic disorder (P?=?6.8×10(-4)), oral ulcers (P?=?6.9×10(-4)) and photosensitivity (P?=?0.002). Immunologic disorder was associated with genotypes more common in Southern European ancestries, whereas the opposite trend was observed for photosensitivity. Oral ulcers were specifically more common in patients of Spanish and Portuguese self-reported ancestry. These results should be taken into account in future research and suggest new hypotheses and possible underlying mechanisms to be investigated. A first hypothesis linking photosensitivity with variation in skin pigmentation is suggested.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.