624 research outputs found

    Estimating the risk of HIV transmission from homosexual men receiving treatment to their HIV-uninfected partners

    Get PDF
    Objective To determine how the risk of HIV transmission from homosexual men receiving antiretroviral treatment is related to patterns of patient monitoring and condom use. Methods A stochastic mathematical simulation model was developed of cohorts of men in the Netherlands who have sex with men (MSM), defining the parameters of the model using observational cohort data. The model incorporates viral load trends during first-line treatment, patient monitoring and different scenarios for the way in which condom use may depend on recent viral load measurements. The model does not include the effect of sexually transmitted infections on HIV transmission. Results For MSM receiving treatment, the risk of transmitting HIV to their long-term partner is 22% (uncertainty interval: 9-37%) if condoms are never used. With incomplete use (in 30% of sex acts) the risk is reduced slightly, to 17% (7-29%). However, the risk is as low as 3% (0.2-8%) when men receiving treatment use condoms only 6 months beyond their last undetectable viral load measurement. The risk is further reduced when 3 months is the time period beyond which condoms are used. Conclusions When condom use by HIV-infected men receiving combination treatment with antiretroviral agents is based on their last viral load measurement, the transmission risk is much lower than with incomplete condom use. The key message for patients is that although always using condoms during treatment is the best way to protect partners from the risk of HIV transmission, when such use cannot be achieved, the second best strategy is to use condoms whenever the last undetectable viral load was measured more than 3 months ag

    Nonlinear Realization of Chiral Symmetry on the Lattice

    Full text link
    We formulate lattice theories in which chiral symmetry is realized nonlinearly on the fermion fields. In this framework the fermion mass term does not break chiral symmetry. This property allows us to use the Wilson term to remove the doubler fermions while maintaining exact chiral symmetry on the lattice. Our lattice formulation enables us to address non-perturbative questions in effective field theories of baryons interacting with pions and in models involving constituent quarks interacting with pions and gluons. We show that a system containing a non-zero density of static baryons interacting with pions can be studied on the lattice without encountering complex action problems. In our formulation one can also decide non-perturbatively if the chiral quark model of Georgi and Manohar provides an appropriate low-energy description of QCD. If so, one could understand why the non-relativistic quark model works.Comment: 34 pages, 2 figures, revised version to be published in J. High Energy Phys. (changes in the 1st paragraph, additional descriptions on the nature of the coordinate singularities in Sec.2, references added

    Salvage surgery for local failures after stereotactic ablative radiotherapy for early stage non-small cell lung cancer

    Get PDF
    markdownabstract__Introduction:__ The literature on surgical salvage, i.e. lung resections in patients who develop a local recurrence following stereotactic ablative radiotherapy (SABR), is limited. We describe our experience with salvage surgery in nine patients who developed a local recurrence following SABR for early stage non-small cell lung cancer (NSCLC). __Methods:__ Patients who underwent surgical salvage for a local recurrence following SABR for NSCLC were identified from two Dutch institutional databases. Complications were scored using the Dindo-Clavien-classification. __Results:__ Nine patients who underwent surgery for a local recurrence were identified. Median time to local recurrence was 22 months. Recurrences were diagnosed with CT- and/or 18FDG-PET-imaging, with four patients also having a pre-surgical pathological diagnosis. Extensive adhesions were observed during two resections, requiring conversion from a thoracoscopic procedure to thoracotomy during one of these procedures. Three patients experienced complications post-surgery; grade 2 (N = 2) and grade 3a (N = 1), respectively. All resection specimens showed viable tumor cells. Median length of hospital stay was 8 days (range 5-15 days) and 30-day mortality was 0 %. Lymph node dissection revealed mediastinal metastases in 3 patients, all of whom received adjuvant therapy. __Conclusions:__ Our experience with nine surgical procedures for local recurrences post-SABR revealed two grade IIIa complications, and a 30-day mortality of 0 %, suggesting that salvage surgery can be safely performed after SABR

    Hepatitis C virus in hemophilia:Health-related quality of life after successful treatment in the sixth Hemophilia in the Netherlands study

    Get PDF
    INTRODUCTION: Persons with hemophilia and hepatitis C virus (HCV) infection have a lower health‐related quality of life (HRQoL) than those never HCV infected. However, it is unknown whether HRQoL after HCV eradication is comparable to individuals never HCV infected. We aimed to compare HRQoL between HCV‐cured and never chronically HCV‐infected persons with hemophilia. METHODS: All persons with hemophilia in the Netherlands were invited for a nationwide study conducted in 2018–2019. For the current analysis, participants born before 1992 with data on HRQoL and HCV status were included. HCV status was collected from medical records. HRQoL was measured by RAND‐36 questionnaire, with a minimally important difference set at 4.0 points. Multivariable linear regression was used to adjust for age, hemophilia severity, HIV status, and self‐reported joint impairment. RESULTS: In total, 486 persons were eligible; 180 were HCV cured and 306 never chronically HCV infected. Compared with those never HCV infected, HCV‐cured individuals were older (57 vs. 53 years), more often had severe hemophilia (67% vs. 21%), and reported more impaired joints (median 3 vs. 0). Compared with those never HCV infected, adjusted RAND‐36 domain scores of HCV‐cured individuals cured were lower on all RAND‐36 domains except Pain, ranging from a difference of 4.5 (95% CI, −8.8 to −0.3) for Physical functioning to 11.3 (95% CI, −19.4 to −3.1) for Role limitations due to physical problems. CONCLUSION: Despite effective HCV treatment, HRQoL of HCV‐cured persons with hemophilia is still lower than HRQoL of those never chronically HCV‐infected on all RAND‐36 domains. This implies that careful psychosocial follow‐up and support are indicated

    Socioeconomic participation of persons with hemophilia:Results from the sixth hemophilia in the Netherlands study

    Get PDF
    Background and objectives Treatment availability and comprehensive care have resulted in improved clinical outcomes for persons with hemophilia. Recent data on socioeconomic participation in the Netherlands are lacking. This study assessed participation in education, in the labor market, and social participation for persons with hemophilia compared with the general male population. Methods Dutch adults and children (5-75 years) of all hemophilia severities (n = 1009) participated in a questionnaire study that included sociodemographic, occupational, and educational variables. Clinical characteristics were extracted from electronic medical records. General population data were extracted from Statistics Netherlands. Social participation was assessed with the PROMIS Ability to Participate in Social Roles and Activities short form, with a minimal important difference set at 1.0. Results Data from 906 adults and children were analyzed. Participation in education of 20 to 24 year olds was 68% (general male population: 53%). Educational attainment was higher compared with Dutch males, especially for severe hemophilia. Absenteeism from school was more common than in the general population. The employment-to-population ratio and occupational disability were worse for severe hemophilia than in the general population (64.3% vs. 73.2% and 14.7% vs. 4.8%, respectively), but similar for nonsevere hemophilia. Unemployment was 5.4% (general male population: 3.4%). Absenteeism from work was less common (38% vs. 45.2%). Mean PROMIS score was similar to or higher than in the general population (54.2; SD 8.9 vs. 50; SD 10). Conclusion Socioeconomic participation of persons with nonsevere hemophilia was similar to the general male population. Some participation outcomes for persons with severe hemophilia were reduced

    Eight common genetic variants associated with serum dheas levels suggest a key role in ageing mechanisms

    Get PDF
    Dehydroepiandrosterone sulphate (DHEAS) is the most abundant circulating steroid secreted by adrenal glands-yet its function is unknown. Its serum concentration declines significantly with increasing age, which has led to speculation that a relative DHEAS deficiency may contribute to the development of common age-related diseases or diminished longevity. We conducted a meta-analysis of genome-wide association data with 14,846 individuals and identified eight independent common SNPs associated with serum DHEAS concentrations. Genes at or near the identified loci include ZKSCAN5 (rs11761528; p = 3.15×10-36), SULT2A1 (rs2637125; p = 2.61×10-19), ARPC1A (rs740160; p = 1.56×10-16), TRIM4 (rs17277546; p = 4.50×10-11), BMF (rs7181230; p = 5.44×10-11), HHEX (rs2497306; p = 4.64×10-9), BCL2L11 (rs6738028; p = 1.72×10-8), and CYP2C9 (rs2185570; p = 2.29×10-8). These genes are associated with type 2 diabetes, lymphoma, actin filament assembly, drug and xenobiotic metabolism, and zinc finger proteins. Several SNPs were associated with changes in gene expression levels, and the related genes are connected to biological pathways linking DHEAS with ageing. This study provides much needed insight into the function of DHEAS

    Relations between lipoprotein(a) concentrations, LPA genetic variants, and the risk of mortality in patients with established coronary heart disease: a molecular and genetic association study

    Get PDF
    Background: Lipoprotein(a) concentrations in plasma are associated with cardiovascular risk in the general population. Whether lipoprotein(a) concentrations or LPA genetic variants predict long-term mortality in patients with established coronary heart disease remains less clear. Methods: We obtained data from 3313 patients with established coronary heart disease in the Ludwigshafen Risk and Cardiovascular Health (LURIC) study. We tested associations of tertiles of lipoprotein(a) concentration in plasma and two LPA single-nucleotide polymorphisms ([SNPs] rs10455872 and rs3798220) with all-cause mortality and cardiovascular mortality by Cox regression analysis and with severity of disease by generalised linear modelling, with and without adjustment for age, sex, diabetes diagnosis, systolic blood pressure, BMI, smoking status, estimated glomerular filtration rate, LDL-cholesterol concentration, and use of lipid-lowering therapy. Results for plasma lipoprotein(a) concentrations were validated in five independent studies involving 10 195 patients with established coronary heart disease. Results for genetic associations were replicated through large-scale collaborative analysis in the GENIUS-CHD consortium, comprising 106 353 patients with established coronary heart disease and 19 332 deaths in 22 studies or cohorts. Findings: The median follow-up was 9·9 years. Increased severity of coronary heart disease was associated with lipoprotein(a) concentrations in plasma in the highest tertile (adjusted hazard radio [HR] 1·44, 95% CI 1·14–1·83) and the presence of either LPA SNP (1·88, 1·40–2·53). No associations were found in LURIC with all-cause mortality (highest tertile of lipoprotein(a) concentration in plasma 0·95, 0·81–1·11 and either LPA SNP 1·10, 0·92–1·31) or cardiovascular mortality (0·99, 0·81–1·2 and 1·13, 0·90–1·40, respectively) or in the validation studies. Interpretation: In patients with prevalent coronary heart disease, lipoprotein(a) concentrations and genetic variants showed no associations with mortality. We conclude that these variables are not useful risk factors to measure to predict progression to death after coronary heart disease is established. Funding: Seventh Framework Programme for Research and Technical Development (AtheroRemo and RiskyCAD), INTERREG IV Oberrhein Programme, Deutsche Nierenstiftung, Else-Kroener Fresenius Foundation, Deutsche Stiftung für Herzforschung, Deutsche Forschungsgemeinschaft, Saarland University, German Federal Ministry of Education and Research, Willy Robert Pitzer Foundation, and Waldburg-Zeil Clinics Isny

    First observation of Bs -> D_{s2}^{*+} X mu nu decays

    Get PDF
    Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays Bs -> Ds+ X mu nu and Bs -> D0 K+ X mu nu are detected. Two structures are observed in the D0 K+ mass spectrum at masses consistent with the known D^+_{s1}(2536) and $D^{*+}_{s2}(2573) mesons. The measured branching fractions relative to the total Bs semileptonic rate are B(Bs -> D_{s2}^{*+} X mu nu)/B(Bs -> X mu nu)= (3.3\pm 1.0\pm 0.4)%, and B(Bs -> D_{s1}^+ X munu)/B(Bs -> X mu nu)= (5.4\pm 1.2\pm 0.5)%, where the first uncertainty is statistical and the second is systematic. This is the first observation of the D_{s2}^{*+} state in Bs decays; we also measure its mass and width.Comment: 8 pages 2 figures. Published in Physics Letters

    Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

    Get PDF
    The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

    Measurement of the flavour composition of dijet events in pp collisions at root s=7 TeV with the ATLAS detector

    Get PDF
    This paper describes a measurement of the flavour composition of dijet events produced in pp collisions at √s=7 TeV using the ATLAS detector. The measurement uses the full 2010 data sample, corresponding to an integrated luminosity of 39 pb−1. Six possible combinations of light, charm and bottom jets are identified in the dijet events, where the jet flavour is defined by the presence of bottom, charm or solely light flavour hadrons in the jet. Kinematic variables, based on the properties of displaced decay vertices and optimised for jet flavour identification, are used in a multidimensional template fit to measure the fractions of these dijet flavour states as functions of the leading jet transverse momentum in the range 40 GeV to 500 GeV and jet rapidity |y|<2.1. The fit results agree with the predictions of leading- and next-to-leading-order calculations, with the exception of the dijet fraction composed of bottom and light flavour jets, which is underestimated by all models at large transverse jet momenta. The ability to identify jets containing two b-hadrons, originating from e.g. gluon splitting, is demonstrated. The difference between bottom jet production rates in leading and subleading jets is consistent with the next-to-leading-order predictions
    corecore