130 research outputs found

    Gastric Marginal Zone B Cell Lymphoma of the Duodenum

    Get PDF
    Small bowel lymphomas of the extranodal type occur in the young and are characteristically associated with malabsorption syndrome. We present the case of an elderly in whom there was no malabsorption and the duodenal tumor was a gastric type marginal zone B cell lymphoma also known as gastric mucosa-associated lymphoid tissue (MALT) lymphoma. A 73-year-old woman presented to the emergency room with 2 weeks of general weakness, recurrent vomiting containing food particles and abdominal distension. She had been diagnosed with diabetic gastroparesis 4 years prior. CT of the abdomen and pelvis was suggestive of gastric outlet obstruction but no evidence of pancreatic or duodenal mass. Endoscopy and biopsy of the tumor obstructing the distal first part of the duodenum confirmed a gastric marginal MALT lymphoma. The patient's symptoms improved with radiotherapy. Gastric MALT lymphoma, an extranodal lymphoma primarily described in the stomach, can also present in the small bowel and is not associated with malabsorption

    American Society of Hematology 2021 guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19

    Get PDF
    Background: Coronavirus disease 2019 (COVID-19)-related critical illness and acute illness are associated with a risk of venous thromboembolism (VTE).Objective: These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in decisions about the use of anticoagulation for thromboprophylaxis for patients with COVID-19-related critical illness and acute illness who do not have confirmed or suspected VTE.Methods: ASH formed a multidisciplinary guideline panel and applied strict management strategies to minimize potential bias from conflicts of interest. The panel included 3 patient representatives. The McMaster University GRADE Centre supported the guideline-development process, including performing systematic evidence reviews (up to 19 August 2020). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, including GRADE Evidence-to-Decision frameworks, to assess evidence and make recommendations, which were subject to public comment.Results: The panel agreed on 2 recommendations. The panel issued conditional recommendations in favor of prophylactic-intensity anticoagulation over intermediate-intensity or therapeutic-intensity anticoagulation for patients with COVID-19-related critical illness or acute illness who do not have confirmed or suspected VTE.Conclusions: These recommendations were based on very low certainty in the evidence, underscoring the need for high-quality, randomized controlled trials comparing different intensities of anticoagulation. They will be updated using a living recommendation approach as new evidence becomes available.Thrombosis and Hemostasi

    The global, regional, and national burden of pancreatic cancer and its attributable risk factors in 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017

    Get PDF
    Background: Worldwide, both the incidence and death rates of pancreatic cancer are increasing. Evaluation of pancreatic cancer burden and its global, regional, and national patterns is crucial to policy making and better resource allocation for controlling pancreatic cancer risk factors, developing early detection methods, and providing faster and more effective treatments. Methods: Vital registration, vital registration sample, and cancer registry data were used to generate mortality, incidence, and disability-adjusted life-years (DALYs) estimates. We used the comparative risk assessment framework to estimate the proportion of deaths attributable to risk factors for pancreatic cancer: smoking, high fasting plasma glucose, and high body-mass index. All of the estimates were reported as counts and age-standardised rates per 100 000 person-years. 95% uncertainty intervals (UIs) were reported for all estimates. Findings: In 2017, there were 448 000 (95% UI 439 000\u2013456 000) incident cases of pancreatic cancer globally, of which 232 000 (210 000\u2013221 000; 51\ub79%) were in males. The age-standardised incidence rate was 5\ub70 (4\ub79\u20135\ub71) per 100 000 person-years in 1990 and increased to 5\ub77 (5\ub76\u20135\ub78) per 100 000 person-years in 2017. There was a 2\ub73 times increase in number of deaths for both sexes from 196 000 (193 000\u2013200 000) in 1990 to 441 000 (433 000\u2013449 000) in 2017. There was a 2\ub71 times increase in DALYs due to pancreatic cancer, increasing from 4\ub74 million (4\ub73\u20134\ub75) in 1990 to 9\ub71 million (8\ub79\u20139\ub73) in 2017. The age-standardised death rate of pancreatic cancer was highest in the high-income super-region across all years from 1990 to 2017. In 2017, the highest age-standardised death rates were observed in Greenland (17\ub74 [15\ub78\u201319\ub70] per 100 000 person-years) and Uruguay (12\ub71 [10\ub79\u201313\ub75] per 100 000 person-years). These countries also had the highest age-standardised death rates in 1990. Bangladesh (1\ub79 [1\ub75\u20132\ub73] per 100 000 person-years) had the lowest rate in 2017, and S\ue3o Tom\ue9 and Pr\uedncipe (1\ub73 [1\ub71\u20131\ub75] per 100 000 person-years) had the lowest rate in 1990. The numbers of incident cases and deaths peaked at the ages of 65\u201369 years for males and at 75\u201379 years for females. Age-standardised pancreatic cancer deaths worldwide were primarily attributable to smoking (21\ub71% [18\ub78\u201323\ub77]), high fasting plasma glucose (8\ub79% [2\ub71\u201319\ub74]), and high body-mass index (6\ub72% [2\ub75\u201311\ub74]) in 2017. Interpretation: Globally, the number of deaths, incident cases, and DALYs caused by pancreatic cancer has more than doubled from 1990 to 2017. The increase in incidence of pancreatic cancer is likely to continue as the population ages. Prevention strategies should focus on modifiable risk factors. Development of screening programmes for early detection and more effective treatment strategies for pancreatic cancer are needed. Funding: Bill & Melinda Gates Foundation

    Measurement of the View the tt production cross-section using eÎŒ events with b-tagged jets in pp collisions at √s = 13 TeV with the ATLAS detector

    Get PDF
    This paper describes a measurement of the inclusive top quark pair production cross-section (σttÂŻ) with a data sample of 3.2 fb−1 of proton–proton collisions at a centre-of-mass energy of √s = 13 TeV, collected in 2015 by the ATLAS detector at the LHC. This measurement uses events with an opposite-charge electron–muon pair in the final state. Jets containing b-quarks are tagged using an algorithm based on track impact parameters and reconstructed secondary vertices. The numbers of events with exactly one and exactly two b-tagged jets are counted and used to determine simultaneously σttÂŻ and the efficiency to reconstruct and b-tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section is measured to be: σttÂŻ = 818 ± 8 (stat) ± 27 (syst) ± 19 (lumi) ± 12 (beam) pb, where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, the integrated luminosity and the LHC beam energy, giving a total relative uncertainty of 4.4%. The result is consistent with theoretical QCD calculations at next-to-next-to-leading order. A fiducial measurement corresponding to the experimental acceptance of the leptons is also presented

    American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19: May 2021 update on the use of intermediate-intensity anticoagulation in critically ill patients

    Get PDF
    Background: COVID-19-related critical illness is associated with an increased risk of venous thromboembolism (VTE). Objective: These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in making decisions about the use of anticoagulation for thromboprophylaxis in patients with COVID-19-related critical illness who do not have confirmed or suspected VTE.Methods: ASH formed a multidisciplinary guideline panel that included 3 patient representatives and applied strategies to minimize potential bias from conflicts of interest. The McMaster University Grading of Recommendations Assessment, Development and Evaluation (GRADE) Centre supported the guideline development process by performing systematic evidence reviews (up to 5 March 2021). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the GRADE approach to assess evidence and make recommendations, which were subject to public comment. This is an update on guidelines published in February 2021.Results: The panel agreed on 1 additional recommendation. The panel issued a conditional recommendation in favor of prophylactic-intensity over intermediate-intensity anticoagulation in patients with COVID-19-related critical illness who do not have confirmed or suspected VTE.Conclusions: This recommendation was based on low certainty in the evidence, which underscores the need for additional high-quality, randomized, controlled trials comparing different intensities of anticoagulation in critically ill patients. Other key research priorities include better evidence regarding predictors of thrombosis and bleeding risk in critically ill patients with COVID-19 and the impact of nonanticoagulant therapies (eg, antiviral agents, corticosteroids) on thrombotic risk.Thrombosis and Hemostasi

    Measurement of the double-differential high-mass Drell-Yan cross section in pp collisions at √s = 8 TeV with the ATLAS detector

    Get PDF
    This paper presents a measurement of the double-differential cross section for the Drell-Yan Z/γ∗ → ℓ+ℓ− and photon-induced γγ → ℓ+ℓ− processes where ℓ is an electron or muon. The measurement is performed for invariant masses of the lepton pairs, mℓℓ, between 116 GeV and 1500 GeV using a sample of 20.3 fb−1 of pp collisions data at centre-of-mass energy of √s = 8 TeV collected by the ATLAS detector at the LHC in 2012. The data are presented double differentially in invariant mass and absolute dilepton rapidity as well as in invariant mass and absolute pseudorapidity separation of the lepton pair. The single-differential cross section as a function of mℓℓ is also reported. The electron and muon channel measurements are combined and a total experimental precision of better than 1% is achieved at low mℓℓ. A comparison to next-to-next-to-leading order perturbative QCD predictions using several recent parton distribution functions and including next-to-leading order electroweak effects indicates the potential of the data to constrain parton distribution functions. In particular, a large impact of the data on the photon PDF is demonstrated

    Search for dark matter produced in association with a hadronically decaying vector boson in pp collisions at sqrt (s) = 13 TeV with the ATLAS detector

    Get PDF
    A search is presented for dark matter produced in association with a hadronically decaying W or Z boson using 3.2 fb−1 of pp collisions at View the MathML sources=13 TeV recorded by the ATLAS detector at the Large Hadron Collider. Events with a hadronic jet compatible with a W or Z boson and with large missing transverse momentum are analysed. The data are consistent with the Standard Model predictions and are interpreted in terms of both an effective field theory and a simplified model containing dark matter

    Measurement of W± and Z-boson production cross sections in pp collisions at √s=13 TeV with the ATLAS detector

    Get PDF
    See paper for full list of authors - 17 pages plus author list + cover pages (34 pages total), 5 figures, 3 tables, submitted to Phys. Lett. B, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2015-03/International audienceMeasurements of the W±→ℓ±ΜW^{\pm} \rightarrow \ell^{\pm} \nu and Z→ℓ+ℓ−Z \rightarrow \ell^+ \ell^- production cross sections (where ℓ±=e±,Ό±\ell^{\pm}=e^{\pm},\mu^{\pm}) in proton-proton collisions at s=13\sqrt{s}=13 TeV are presented using data recorded by the ATLAS experiment at the Large Hadron Collider, corresponding to a total integrated luminosity of 81 pb−1^{-1}. The total inclusive W±W^{\pm}-boson production cross sections times the single-lepton-flavour branching ratios are σW+tot=11.78±0.02(stat)±0.32(sys)±0.59(lumi)\sigma_{W^+}^{tot}= 11.78 \pm 0.02 (stat) \pm 0.32 (sys) \pm 0.59 (lumi) nb and σW−tot=8.75±0.02(stat)±0.24(sys)±0.44(lumi)\sigma_{W^-}^{tot} = 8.75 \pm 0.02 (stat) \pm 0.24 (sys) \pm 0.44 (lumi) nb for W+W^+ and W−W^-, respectively. The total inclusive ZZ-boson production cross section times leptonic branching ratio, within the invariant mass window 66<mℓℓ<11666 < m_{\ell\ell} < 116 GeV, is σZtot=1.97±0.01(stat)±0.04(sys)±0.10(lumi)\sigma_{Z}^{tot} = 1.97 \pm 0.01 (stat) \pm 0.04 (sys) \pm 0.10 (lumi) nb. The W+W^+, W−W^-, and ZZ-boson production cross sections and cross-section ratios within a fiducial region defined by the detector acceptance are also measured. The cross-section ratios benefit from significant cancellation of experimental uncertainties, resulting in σW+fid/σW−fid=1.295±0.003(stat)±0.010(sys)\sigma_{W^+}^{fid}/\sigma_{W^-}^{fid} = 1.295 \pm 0.003 (stat) \pm 0.010 (sys) and σW±fid/σZfid=10.31±0.04(stat)±0.20(sys)\sigma_{W^{\pm}}^{fid}/\sigma_{Z}^{fid} = 10.31 \pm 0.04 (stat) \pm 0.20 (sys). Theoretical predictions, based on calculations accurate to next-to-next-to-leading order for quantum chromodynamics and next-to-leading order for electroweak processes and which employ different parton distribution function sets, are compared to these measurements

    Search for resonances in the mass distribution of jet pairs with one or two jets identified as b-jets in proton–proton collisions at √s=13TeV with the ATLAS detector

    Get PDF
    Searches for high-mass resonances in the dijet invariant mass spectrum with one or two jets identi-fied as b-jets are performed using an integrated luminosity of 3.2fb−1of proton–proton collisions with a centre-of-mass energy of √s=13TeVrecorded by the ATLAS detector at the Large Hadron Collider. Noevidence of anomalous phenomena is observed in the data, which are used to exclude, at 95%credibility level, excited b∗quarks with masses from 1.1TeVto 2.1TeVand leptophobic Z bosons with masses from 1.1TeVto 1.5TeV. Contributions of a Gaussian signal shape with effective cross sections ranging from approximately 0.4 to 0.001pb are also excluded in the mass range 1.5–5.0TeV

    Measurement of the top quark mass in the tt→ dilepton channel from √s = 8 TeV ATLAS data

    Get PDF
    The top quark mass is measured in the ttÂŻ → dilepton channel (lepton = e,ÎŒ) using ATLAS data recorded in the year 2012 at the LHC. The data were taken at a proton proton centre-of-mass energy of √s = 8 TeV and correspond to an integrated luminosity of about 20.2 fb−1. Exploiting the template method, and using the distribution of invariant masses of lepton–b-jet pairs, the top quark mass is measured to be mtop = 172.99±0.41 (stat) ±0.74 (syst) GeV, with a total uncertainty of 0.84 GeV. Finally, a combination with previous ATLAS mtop measurements from √s = 7 TeV data in the ttÂŻ → dilepton and ttÂŻ → lepton + jets channels results in mtop = 172.84±0.34 (stat)±0.61 (syst) GeV, with a total uncertainty of 0.70 GeV
    • 

    corecore