Isoflurane Induces Endothelial Apoptosis of the Post-Hypoxic Blood-Brain Barrier in a Transdifferentiated Human Umbilical Vein Edothelial Cell Model

Isoflurane is a popular volatile anesthetic agent used in humans as well as in experimental animal research. In previous animal studies of the blood-brain barrier (BBB), observations towards an increased permeability after exposure to isoflurane are reported. In this study we investigated the effect of a 2-hour isoflurane exposure on apoptosis of the cerebral endothelium following 24 hours of hypoxia in an in vitro BBB model using astrocyte-conditioned human umbilical vein endothelial cells (AC-HUVECs). Apoptosis of AC-HUVECs was investigated using light microscopy of the native culture for morphological changes, Western blot (WB) analysis of Bax and Bcl-2, and a TUNEL assay. Treatment of AC-HUVECs with isoflurane resulted in severe cellular morphological changes and a significant dose-dependent increase in DNA fragmentation, which was observed during the TUNEL assay analysis. WB analysis confirmed increases in pro-apoptotic Bax levels at 4 hours and 24 hours and decreases in anti-apoptotic Bcl-2 in a dose-dependent manner compared with the control group. These negative effects of isoflurane on the BBB after a hypoxic challenge need to be taken into account not only in experimental stroke research, but possibly also in clinical practice

Gluon-induced W-boson pair production at the LHC

Pair production of W bosons constitutes an important background to Higgs boson and new physics searches at the Large Hadron Collider LHC. We have calculated the loop-induced gluon-fusion process gg -> W*W* -> leptons, including intermediate light and heavy quarks and allowing for arbitrary invariant masses of the W bosons. While formally of next-to-next-to-leading order, the gg -> W*W* -> leptons process is enhanced by the large gluon flux at the LHC and by experimental Higgs search cuts, and increases the next-to-leading order WW background estimate for Higgs searches by about 30%. We have extended our previous calculation to include the contribution from the intermediate top-bottom massive quark loop and the Higgs signal process. We provide updated results for cross sections and differential distributions and study the interference between the different gluon scattering contributions. We describe important analytical and numerical aspects of our calculation and present the public GG2WW event generator.Comment: 20 pages, 4 figure

Combining Monte Carlo generators with next-to-next-to-leading order calculations: event reweighting for Higgs boson production at the LHC

We study a phenomenological ansatz for merging next-to-next-to-leading order (NNLO) calculations with Monte Carlo event generators. We reweight them to match bin-integrated NNLO differential distributions. To test this procedure, we study the Higgs boson production cross-section at the LHC, for which a fully differential partonic NNLO calculation is available. We normalize PYTHIA and MC@NLO Monte Carlo events for Higgs production in the gluon fusion channel to reproduce the bin integrated NNLO double differential distribution in the transverse momentum and rapidity of the Higgs boson. These events are used to compute differential distributions for the photons in the pp \to H \to \gamma \gamma decay channel, and are compared to predictions from fixed-order perturbation theory at NNLO. We find agreement between the reweighted generators and the NNLO result in kinematic regions where we expect a good description using fixed-order perturbation theory. Kinematic boundaries where resummation is required are also modeled correctly using this procedure. We then use these events to compute distributions in the pp \to H \to W^+W^- \to l^+l^- \nu\bar{\nu} channel, for which an accurate description is needed for measurements at the LHC. We find that the final state lepton distributions obtained from PYTHIA are not significantly changed by the reweighting procedure.Comment: 18 pages, 14 fig

Diagnosis of pericardial effusion with a new generation hand-carried ultrasound device in cardiothoracic intensive care unit patients

Background: Technological advances introduced hand-carried ultrasound (HCU) imagers in daily clinical workflow providing several benefits such as fast bedside availability and prompt diagnosis. Purpose: To evaluate the diagnostic yield of a latest generation HCU imager compared to contrast-enhanced multidetector computed tomography (MDCT) for the detection of pericardial effusion (PE) in cardiothoracic intensive care unit (ICU) patients. Material and Methods: Thirty-six patients from a cardiothoracic ICU were enrolled to this study irrespective of their underlying disease. All patients were examined with a new generation HCU for the presence of PE. Definite diagnosis of PE was based on findings of MDCT as standard of reference. Statistical analysis was performed using PASW 18. Results: PE was identified in 20 patients by MDCT (prevalence 56%). The HCU examination was carried out technically successfully in all patients. Sensitivity, specificity, positive and negative predictive value of HCU for the diagnosis of PE were 75%, 88%, 88%, and 74%, respectively. Conclusion: HCU provides rapid, practical, reliable, and cost-effective diagnosis of PE in patients on cardiothoracic ICU

Electroweak radiative corrections to W-boson production at hadron colliders

The complete set of electroweak O(alpha) corrections to the Drell--Yan-like production of W bosons is calculated and compared to an approximation provided by the leading term of an expansion about the W-resonance pole. All relevant formulae are listed explicitly, and particular attention is paid to issues of gauge invariance and the instability of the W bosons. A detailed discussion of numerical results underlines the phenomenological importance of the electroweak corrections to W-boson production at the Tevatron and at the LHC. While the pole expansion yields a good description of resonance observables, it is not sufficient for the high-energy tail of transverse-momentum distributions, relevant for new-physics searches.Comment: 29 pages, latex, 17 postscript files, revised version that is to appear in Phys.Rev.D, some explanations added and results extended by a discussion of the QED factorization scale dependenc

QCD

We discuss issues of QCD at the LHC including parton distributions, Monte Carlo event generators, the available next-to-leading order calculations, resummation, photon production, small x physics, double parton scattering, and backgrounds to Higgs production.Comment: 115 pages, Latex, 47 figures, to appear in the Report of the ``1999 CERN Workshop on SM Physics (and more) at the LHC'', S. Catani, M. Dittmar, D. Soper, W.J. Stirling, S. Tapprogge (convenors

Eigenständige Analgesie mit Piritramid durch Notfallsanitäter – retrospektive Auswertung der elektronischen Einsatzdokumentation

Hintergrund Schmerzen sind ein häufiger Behandlungsgrund in der prähospitalen Notfallmedizin. In Bayern delegieren die Ärztlichen Leiter Rettungsdienst (ÄLRD) bei subjektiv nichttolerablen Schmerzen nach isoliertem Extremitätentrauma an Notfallsanitäter (NotSan) landesweit einheitlich die Kurzinfusion von 7,5 mg des Opioidanalgetikums Piritramid. Methode Die Routineeinsatzdokumentation aller Einsätze im bayerischen Rettungsdienst mit Heranziehungen des Delegationsalgorithmus „Isolierte Extremitätenverletzung“ der ÄLRD nach § 4 Abs. 2 Nr. 2c Notfallsanitätergesetz wurde über einen 2‑Jahres-Zeitraum ausgewertet. Evaluiert wurden der Effekt auf die Schmerzintensität nach der numerischen Rating-Skala (NRS) und dem Vorliegen nichttolerabler Schmerzen, Auswirkungen auf die Vitalfunktionen sowie die Notwendigkeit von bestimmten weitergehenden Interventionen. Ergebnisse Bei 7151 identifizierten Einsätzen erfolgte in 6097 Fällen eine eigenständige Analgesie durch NotSan entlang der Delegation der ÄLRD. Die Schmerzintensität nach der NRS konnte von im Median 7 (Interquartilsabstand [IQR] 2) auf 3 (IQR 2, p < 0,001) gesenkt und in 96,9 % ein aus Patientensicht tolerables Niveau erreicht werden. In 9,4 % der Fälle wurde ein Notarzt nachgefordert und in 5,0 % eine ergänzende Analgesie verabreicht. Etwa jeder zehnte Patient erhielt Sauerstoff. Atemwegsinterventionen waren in wenigen Einzelfällen notwendig, eine Antagonisierung nur nach höheren als den delegierten Opiatdosen. Schlussfolgerung Eine vom ÄLRD delegierte und von NotSan eigenständig durchgeführte Opiatgabe senkt das Schmerzniveau relevant. Wesentliche Hinweise auf eine Patientengefährdung fanden sich nicht. Durch dieses Verfahren konnten in Bayern jährlich geschätzt ca. 2500 Notarzteinsätze vermieden werden

Neutrino Mass and μ→e+γ\mu \rightarrow e + \gamma from a Mini-Seesaw

The recently proposed "mini-seesaw mechanism" combines naturally suppressed Dirac and Majorana masses to achieve light Standard Model neutrinos via a low-scale seesaw. A key feature of this approach is the presence of multiple light (order GeV) sterile-neutrinos that mix with the Standard Model. In this work we study the bounds on these light sterile-neutrinos from processes like \mu ---> e + \gamma, invisible Z-decays, and neutrinoless double beta-decay. We show that viable parameter space exists and that, interestingly, key observables can lie just below current experimental sensitivities. In particular, a motivated region of parameter space predicts a value of BR(\mu ---> e + \gamma) within the range to be probed by MEG.Comment: 1+26 pages, 7 figures. v2 JHEP version (typo's fixed, minor change to presentation, results unchanged

Electroweak Physics

We review the prospects for studies in electroweak physics at the LHC