Bench-to-bedside review: Current evidence for extracorporeal albumin dialysis systems in liver failure

Acute liver failure (ALF) and acute on chronic liver failure (AoCLF) carry a high mortality. The rationale for extracorporeal systems is to provide an environment facilitating recovery or a window of opportunity for liver transplantation. Recent technologies have used albumin as a scavenging molecule. Two different albumin dialysis systems have been developed using this principle: MARS (Molecular Adsorbent Recirculation System) and SPAD (Single-Pass Albumin Dialysis). A third system, Prometheus (Fractionated Plasma Separation and Adsorption), differs from the others in that the patient's albumin is separated across a membrane and then is run over adsorptive columns. Although several trials have been published (particularly with MARS), currently there is a lack of controlled studies with homogenous patient populations. Many studies have combined patients with ALF and AoCLF. Others have included patients with different etiologies. Although MARS and Prometheus have shown biochemical improvements in AoCLF and ALF, additional studies are required to show conclusive benefit in short- and long-term survival. The appropriate comparator is standard medical therapy rather than head-to-head comparisons of different forms of albumin dialysis

Prospective study of biliary strictures to determine the predictors of malignancy

ORIGINAL ARTICLE BACKGROUND: There have been few prospective studies regarding the investigation of biliary strictures, principally because of rapid technological change. The present study was designed to determine the sensitivity of various imaging studies for the detection of biliary strictures. Serum biochemistry and imaging studies were evaluated for their role in distinguishing benign from malignant strictures. METHODS: Thirty-one patients with suspected noncalculus biliary obstruction were enrolled consecutively in the study. A complete biochemical profile, ultrasound, Disida scan and cholangiogram (endoscopic retrograde cholangiopancreatography [ERCP] or percutaneous cholangiogram) were obtained at study entry. Stricture etiology was determined based on cytology, biopsy and/or clinical follow-up at one year. RESULTS: Twenty-nine of 31 patients had biliary strictures, of which 15 were malignant. The mean age of the malignant cohort was 73.9 years versus 53.9 years in the benign cohort (P<0.001). Statistically significant differences between the malignant and benign groups, respectively, were as follows: alanine transaminase 235.2 versus 66.9 U/L (P=0.004), aspartate transaminase 189.8 versus 84.5 U/L (P=0.011), alkaline phosphatase 840.2 versus 361.1 U/L (P=0.002), bilirubin 317.8 versus 22.1 µmol/L (P<0.001) and bile acids 242.5 versus 73.2 µmol/L (P=0.001). Threshold analysis using receiver operative characteristic (ROC) curves demonstrated that a bilirubin level of 75 µmol/L was most predictive of malignant strictures. Intrahepatic duct dilation was present in 93% of malignant strictures versus 36% of benign strictures (P=0.002). Common hepatic duct dilation was less discriminatory (malignant 13.5 versus benign 9.6 mm; P=0.11). Ultrasound was highly sensitive (93%) in the detection of the primary tumour in the bile duct or pancreas, or in the visualization of nodal or liver metastases. In benign disease, ultrasound failed to detect evidence of intrahepatic or extrahepatic biliary dilation in most cases. Disida scans were not able to distinguish between malignant or benign strictures and could not accurately localize the level of obstruction. The sensitivity of Disida scan for the diagnosis of obstruction was 50%. Cholangiographic characterization of strictures revealed an equal distribution of smooth (eight of 13) and irregular (five of 13) strictures in the malignant group. Ten of 13 benign strictures were characterized as smooth. Malignant strictures were significantly longer than benign ones -30.3 versus 9.2 mm (P=0.001). Threshold analysis using ROC curves showed that strictures greater than or equal to 14 mm were predictive of malignancy (sensitivity 78%, specificity 75%, log odds ratio 11.23). CONCLUSIONS: A serum bilirubin level of 75 µmol/L or higher, or a stricture length of greater than 14 mm was highly predictive of malignancy in patients with a biliary stricture. Ultrasound was useful in predicting malignant strictures by detecting either intrahepatic duct dilation or by visualizing the tumour (primary or metastases). Strictures with a 'benign' cholangiographic appearance are frequently malignant. Disida scan did not add additional information. ERCP is necessary to diagnose benign strictures, which tend to be less extensive at presentation. B iliary strictures are a challenging problem for the clinician. By the time that patients with biliary strictures are referred to a specialist, the diagnosis is usually already known or strongly suspected because clinical evaluation and noninvasive investigations alone have a high specificity and sensitivity (1-4). The job of the medical or surgical specialist is not only to confirm the diagnosis of biliary stricture but also, importantly, to define the etiology and the exact anatomic location, which is vital to therapeutic planning. The differentiation between benign and malignant strictures can be difficult but is of obvious importance in regard to prognosis and optimal therapy. Numerous imaging modalities are available for the investigation of biliary strictures, including abdominal ultrasound, computed tomographic (CT) scanning, nuclear imaging, percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiopancreatography (ERCP) and most recently magnetic resonance cholangiopancreatography (MRCP). Comparative and descriptive studies in this area are lacking, primarily because rapid technological improvements and developments outdate them. We, therefore, embarked on a prospective descriptive trial with the following aims: · Determine the predictive value of liver enzymes, serum bilirubin, serum bile acids, ultrasound and diethyl-iminodiacetic acid (Disida) nuclear imaging for the presence of malignant biliary strictures. · Measure the ability of ultrasound and nuclear imaging to localize the level of obstruction using direct cholangiography as the gold standard. · Determine the sensitivity of abdominal ultrasound and Disida nuclear scanning for the detection of biliary strictures. · Investigate the utility of various cholangiographic features to distinguish malignant from benign strictures. PATIENTS AND METHODS Patients: All patients with biliary strictures referred to the Division of Gastroenterology at the University of Alberta Hospitals for investigation between January 1, 1995 and December 31, 1995 were prospectively entered into the trial. The inclusion criteria were age 16 years or older and noncalculus biliary obstruction. Patients were excluded if subsequent evaluation did not show a stricture. Ethics committee approval was obtained. sente dans 93 % des sténoses malignes par rapport à 36 % des sténoses béni-gnes (P = 0,002). Une dilatation du canal hépatique commun était moins discriminatoire (13,5 mm en cas de malignité par rapport à 9,6 mm en cas de bénignité, P = 0,11). L'échographie était hautement sensible (93 %) pour déceler la tumeur primaire dans le canal biliaire ou le pancréas, ou pour visualiser les nodules ou les métastases hépatiques. Dans le cas d'une maladie bénigne, l'échogra-phie n'a pas réussi à déceler la présence d'une dilatation biliaire intra-hépa-tique ou extra-hépatique dans la plupart des cas. Les scintigraphies au disida n'ont pas pu différencier les sténoses malignes des sténoses bénignes ou localiser précisément le niveau de l'obstruction. La sensibilité des scintigraphies au disida pour établir un diagnostic d'obstruction était de 50 %. La caractérisation cholangiographique des sténoses a révélé une distribution égale de sténoses lisses (huit sur 13) et irrégulières (cinq sur 13) dans le groupe des sténoses malignes. Dix des 13 sténoses bénignes ont été qualifiées de lisses. Les sténoses malignes étaient nettement plus longues que les sténoses bénignes, soit 30,3 mm par rapport à 9,2 mm (P=0,001). L'analyse des seuils au moyen des courbes ROC a révélé que des sténoses supérieures ou égales à 14 mm étaient un prédicteur de malignité (sensibilité de 78 %, spécificité de 75 %, risque relatif logarithmique de 11,23). CONCLUSIONS : Un niveau de bilirubine sérique de 75 µmol/L ou une longueur de sténose de 14 mm étaient fortement prédictifs de malignité chez les patients atteints d'une sténose biliaire. L'échographie était utile pour prédire les sténoses malignes en décelant soit une dilatation du canal intra-hépatique ou en visualisant la tumeur (primaire ou métastases). Les sténoses d'apparence « bénigne » à la cholangiographie s'avèrent souvent malignes. La scintigraphie au disida n'apportait pas d'informations supplé-mentaires. Une CPRE est nécessaire pour diagnostiquer des sténoses bénignes, qui ont tendance à être moins étendues à l'examen. · Abdominal ultrasound examination with particular attention to intrahepatic biliary dilation, extrahepatic duct calibre, presence or absence of gallbladder and other relevant pathology such as tumour mass or ductal stones. · Disida scan. Patients were examined after a 4 h fast. Opiates were withheld for the proceeding 24 h. In addition to the standard scan, data were collected for deconvolutional analysis to determine hepatic extraction fraction and time activity curve so that the half-life of biliary excretion and time to peak activity could be analyzed. · Cholangiography. ERCP was attempted first in all patients with failures proceeding to PTC. Cefazoline 1 g was administered intravenously 30 to 60 mins before cholangiography. The biliary system was filled as completely as possible using 50% Conray 60 (Mallenchrodt, St Louis, Missouri) contrast injected under low pressure. The information obtained from each cholangiogram included site of stricture, multiplicity, character (smoothly tapered versus irregular or shouldered), stricture(s) length, minimal stricture width, maximal proximal biliary dilation and other information (ampullary mass, primary sclerosing cholangitis, cancer of the pancreas). All data were to be collected within five working days so that the different imaging modalities tested would be comparable. All imaging studies were interpreted by radiologists blinded to the results of the patients' other diagnostic studies. The ERCP data were obtained last so that a biliary stent could be inserted if indicated. The cholangiographic measurements were confirmed by two independent observers. Stricture etiology was defined by cytology or biopsy histology or by clinical outcome after one year. Statistical analysis: Statistical analysis was performed using SPSS. Between-groups differences in mean values of continuous variables were tested by independent samples t tests or by nonparametric Mann-Whitney Rank Sum tests when the distributions were not normal. The differences in frequencies of categorical variables were tested by c 2 test with Yates' correction for continuity or by Fisher's exact test when the expected number of observations per cell was less than five. Associations between continuous variables were assessed by Pearson correlation coefficient. Logistic regression analysis was used to analyze the association of dichotomous outcome variable (malignant versus benign) with continuous and categorical predictor variables. The statistical inferences were based on the level of significance P<0.05. Receiver operating characteristic (ROC) curves were constructed for the biochemical variables. To determine optimal threshold levels for each diagnostic parameter, ROC plots were constructed using the observed true and false positive rates at each potential threshold level. A best fit ROC curve was constructed according to methods published elsewhere (5,6). The threshold value providing the best compromise between true and false positive rates was estimated from the ROC plot. Likelihood ratios were calculated from the fitted ROC curve. RESULTS Thirty-one patients were enrolled in the study. Two patients were excluded -one because he did not have a stricture and one whose suspected stricture was unevaluable because of previous biliary bypass and contraindication for PTC as a result of coagulopathy. Of the remaining 29 patients, 15 were diagnosed with malignant strictures and 14 with benign strictures. Two patients had primary sclerosing cholangitis, both of whom had multiple strictures. Patient demographics and underlying diagnosis are shown i

Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes

Background: Regulatory guidance specifies the need to establish cardiovascular safety of new diabetes therapies in patients with type 2 diabetes in order to rule out excess cardiovascular risk. The cardiovascular effects of semaglutide, a glucagon-like peptide 1 analogue with an extended half-life of approximately 1 week, in type 2 diabetes are unknown. Methods: We randomly assigned 3297 patients with type 2 diabetes who were on a standard-care regimen to receive once-weekly semaglutide (0.5 mg or 1.0 mg) or placebo for 104 weeks. The primary composite outcome was the first occurrence of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. We hypothesized that semaglutide would be noninferior to placebo for the primary outcome. The noninferiority margin was 1.8 for the upper boundary of the 95% confidence interval of the hazard ratio. Results: At baseline, 2735 of the patients (83.0%) had established cardiovascular disease, chronic kidney disease, or both. The primary outcome occurred in 108 of 1648 patients (6.6%) in the semaglutide group and in 146 of 1649 patients (8.9%) in the placebo group (hazard ratio, 0.74; 95% confidence interval [CI], 0.58 to 0.95; P<0.001 for noninferiority). Nonfatal myocardial infarction occurred in 2.9% of the patients receiving semaglutide and in 3.9% of those receiving placebo (hazard ratio, 0.74; 95% CI, 0.51 to 1.08; P=0.12); nonfatal stroke occurred in 1.6% and 2.7%, respectively (hazard ratio, 0.61; 95% CI, 0.38 to 0.99; P=0.04). Rates of death from cardiovascular causes were similar in the two groups. Rates of new or worsening nephropathy were lower in the semaglutide group, but rates of retinopathy complications (vitreous hemorrhage, blindness, or conditions requiring treatment with an intravitreal agent or photocoagulation) were significantly higher (hazard ratio, 1.76; 95% CI, 1.11 to 2.78; P=0.02). Fewer serious adverse events occurred in the semaglutide group, although more patients discontinued treatment because of adverse events, mainly gastrointestinal. Conclusions: In patients with type 2 diabetes who were at high cardiovascular risk, the rate of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke was significantly lower among patients receiving semaglutide than among those receiving placebo, an outcome that confirmed the noninferiority of semaglutide. (Funded by Novo Nordisk; SUSTAIN-6 ClinicalTrials.gov number, NCT01720446.)Sin financiación72.406 JCR (2016) Q1, 1/155 Medicine, General & InternalUE

Standalone vertex finding in the ATLAS muon spectrometer

A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson

Measurement of the top quark pair cross section with ATLAS in pp collisions at √s=7 TeV using final states with an electron or a muon and a hadronically decaying τ lepton

A measurement of the cross section of top quark pair production in proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 7 TeV is reported. The data sample used corresponds to an integrated luminosity of 2.05 fb -1. Events with an isolated electron or muon and a τ lepton decaying hadronically are used. In addition, a large missing transverse momentum and two or more energetic jets are required. At least one of the jets must be identified as originating from a b quark. The measured cross section, σtt-=186±13(stat.)±20(syst.)±7(lumi.) pb, is in good agreement with the Standard Model prediction

Measurement of the top quark-pair production cross section with ATLAS in pp collisions at \sqrt{s}=7\TeV

A measurement of the production cross-section for top quark pairs(\ttbar) in $pp$ collisions at \sqrt{s}=7 \TeV is presented using data recorded with the ATLAS detector at the Large Hadron Collider. Events are selected in two different topologies: single lepton (electron $e$ or muon $\mu$) with large missing transverse energy and at least four jets, and dilepton ($ee$, $\mu\mu$ or $e\mu$) with large missing transverse energy and at least two jets. In a data sample of 2.9 pb-1, 37 candidate events are observed in the single-lepton topology and 9 events in the dilepton topology. The corresponding expected backgrounds from non-\ttbar Standard Model processes are estimated using data-driven methods and determined to be $12.2 \pm 3.9$ events and $2.5 \pm 0.6$ events, respectively. The kinematic properties of the selected events are consistent with SM \ttbar production. The inclusive top quark pair production cross-section is measured to be \sigmattbar=145 \pm 31 ^{+42}_{-27} pb where the first uncertainty is statistical and the second systematic. The measurement agrees with perturbative QCD calculations.Comment: 30 pages plus author list (50 pages total), 9 figures, 11 tables, CERN-PH number and final journal adde

Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of √s=7 TeV proton-proton collisions

Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter