8 research outputs found

    Development of new chemical tools to study the cannabinoid receptor type 2

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    The endocannabinoid receptors CB1R and CB2R are involved in a plethora of processes, and consequently are involved in many pathological conditions. Their wide distribution makes the CBRs both an interesting therapeutic target and hard to study. Additional chemical tools are required to study and understand the function and mechanism of CB1R and CB2R. This thesis describes the development of several such tools to improve our insight in the (pathological) roles of the receptors in order to develop novel and improved therapeutics. First evaluation of three dimensional ligand-CB2R complexes made and analysed with Cryo-EM are described. Hotspots that potentially generate selectivity between CB1R and CB2R are evaluated with point-mutations in vitro. Consequently describes the development of the first tools, two-step bifunctional probes based on LEI-121 and LEI 102, is described. As two-step probes are not compatible with every assay, the toolbox is expanded with a one-step fluorescent probe. Briefly touching upon CB1R, ligands were designed with negatively charged phosphonium groups that are potentially selective for mtCB1R. Molecular Physiolog

    Structural basis of selective cannabinoid CB2 receptor activation

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    Cannabinoid CB2 receptor (CB2R) agonists are investigated as therapeutic agents in the clinic. However, their molecular mode-of-action is not fully understood. Here, we report the discovery of LEI-102, a CB2R agonist, used in conjunction with three other CBR ligands (APD371, HU308, and CP55,940) to investigate the selective CB2R activation by binding kinetics, site-directed mutagenesis, and cryo-EM studies. We identify key residues for CB2R activation. Highly lipophilic HU308 and the endocannabinoids, but not the more polar LEI-102, APD371, and CP55,940, reach the binding pocket through a membrane channel in TM1-TM7. Favorable physico-chemical properties of LEI-102 enable oral efficacy in a chemotherapy-induced nephropathy model. This study delineates the molecular mechanism of CB2R activation by selective agonists and highlights the role of lipophilicity in CB2R engagement. This may have implications for GPCR drug design and sheds light on their activation by endogenous ligands

    Higgs Boson Studies at the Tevatron

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    We combine searches by the CDF and D0 Collaborations for the standard model Higgs boson with mass in the range 90--200 GeV/c2/c^2 produced in the gluon-gluon fusion, WHWH, ZHZH, ttˉHt{\bar{t}}H, and vector boson fusion processes, and decaying in the HbbˉH\rightarrow b{\bar{b}}, HW+WH\rightarrow W^+W^-, HZZH\rightarrow ZZ, Hτ+τH\rightarrow\tau^+\tau^-, and HγγH\rightarrow \gamma\gamma modes. The data correspond to integrated luminosities of up to 10 fb1^{-1} and were collected at the Fermilab Tevatron in ppˉp{\bar{p}} collisions at s=1.96\sqrt{s}=1.96 TeV. The searches are also interpreted in the context of fermiophobic and fourth generation models. We observe a significant excess of events in the mass range between 115 and 140 GeV/c2c^2. The local significance corresponds to 3.0 standard deviations at mH=125m_H=125 GeV/c2c^2, consistent with the mass of the Higgs boson observed at the LHC, and we expect a local significance of 1.9 standard deviations. We separately combine searches for HbbˉH \to b\bar{b}, HW+WH \to W^+W^-, Hτ+τH\rightarrow\tau^+\tau^-, and HγγH\rightarrow\gamma\gamma. The observed signal strengths in all channels are consistent with the presence of a standard model Higgs boson with a mass of 125 GeV/c2c^2

    A Deep Neural Network for Simultaneous Estimation of b Jet Energy and Resolution

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    We describe a method to obtain point and dispersion estimates for the energies of jets arising from b quarks produced in proton–proton collisions at an energy of s=13TeV at the CERN LHC. The algorithm is trained on a large sample of simulated b jets and validated on data recorded by the CMS detector in 2017 corresponding to an integrated luminosity of 41 fb-1. A multivariate regression algorithm based on a deep feed-forward neural network employs jet composition and shape information, and the properties of reconstructed secondary vertices associated with the jet. The results of the algorithm are used to improve the sensitivity of analyses that make use of b jets in the final state, such as the observation of Higgs boson decay to b b ¯. © 2020, The Author(s)

    Evidence for a Particle Produced in Association with Weak Bosons and Decaying to a Bottom-Antibottom Quark Pair in Higgs Boson Searches at the Tevatron

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    We combine searches by the CDF and D0 Collaborations for the associated production of a Higgs boson with a W or Z boson and subsequent decay of the Higgs boson to a bottom-antibottom quark pair. The data, originating from Fermilab Tevatron p[bar over p] collisions at √s=1.96  TeV, correspond to integrated luminosities of up to 9.7  fb[superscript -1]. The searches are conducted for a Higgs boson with mass in the range 100–150  GeV/c[superscript 2]. We observe an excess of events in the data compared with the background predictions, which is most significant in the mass range between 120 and 135  GeV/c[superscript 2]. The largest local significance is 3.3 standard deviations, corresponding to a global significance of 3.1 standard deviations. We interpret this as evidence for the presence of a new particle consistent with the standard model Higgs boson, which is produced in association with a weak vector boson and decays to a bottom-antibottom quark pair

    GM in Asian Auto Markets

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    We combine searches by the CDF and D0 collaborations for a Higgs boson decaying to W+W-. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) fb-1 of p-pbar collisions at sqrt{s}=1.96 TeV at the Fermilab Tevatron collider. No excess is observed above background expectation, and resulting limits on Higgs boson production exclude a standard-model Higgs boson in the mass range 162-166 GeV at the 95% C.L

    Measurements with silicon photomultipliers of dose-rate effects in the radiation damage of plastic scintillator tiles in the CMS hadron endcap calorimeter

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    Measurements are presented of the reduction of signal output due to radiation damage for two types of plastic scintillator tiles used in the hadron endcap (HE) calorimeter of the CMS detector. The tiles were exposed to particles produced in proton-proton (pp) collisions at the CERN LHC with a center-of-mass energy of 13 TeV, corresponding to a delivered luminosity of 50 fb-1. The measurements are based on readout channels of the HE that were instrumented with silicon photomultipliers, and are derived using data from several sources: A laser calibration system, a movable radioactive source, as well as hadrons and muons produced in pp collisions. Results from several irradiation campaigns using 60Co sources are also discussed. The damage is presented as a function of dose rate. Within the range of these measurements, for a fixed dose the damage increases with decreasing dose rate
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