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Mechanochemical C-H Arylation and Alkylation of Indoles Using 3 d Transition Metal and Zero-Valent Magnesium. Chemistry 2024; 30:e202304231. [PMID: 38294073 DOI: 10.1002/chem.202304231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/31/2024] [Accepted: 01/31/2024] [Indexed: 02/01/2024]
Abstract
Although the 3 d transition-metal catalyzed C-H functionalization have been extensively employed to promote the formation of valuable carbon-carbon bonds, the persistent problems, including the use of sensitive Grignard reagents and the rigorous operations (solvent-drying, inert gas protection, metal pre-activation and RMgX addition rate control), still leave great room for further development of sustainable methodologies. Herein, we report a mechanochemical technology toward in-situ preparation of highly sensitive organomagnesium reagents, and thus building two general 3 d transition-metal catalytic platforms that enables regioselective arylation and alkylation of indoles with a wide variety of halides (including those containing post transformable functionalities and heteroaromatic rings). This mechanochemical strategy also brings unique reactivity and high step-economy in producing functionalized N-free indole products.
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Photodynamic anticancer activity evaluation of novel 5-aminolevulinic acid and 3-hydroxypyridinone conjugates. Bioorg Med Chem 2024; 105:117726. [PMID: 38626642 DOI: 10.1016/j.bmc.2024.117726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/08/2024] [Accepted: 04/12/2024] [Indexed: 04/18/2024]
Abstract
5-Aminolevulinic acid (ALA) and its derivatives, serving as the endogenous precursor of the photosensitizer (PS) protoporphyrin IX (PpIX), successfully applied in tumor imaging and photodynamic therapy (PDT). ALA and its derivatives have been used to treat actinic keratosis (AK), basal cell carcinoma (BCC), and improve the detection of superficial bladder cancer. However, the high hydrophilicity of ALA and the conversion of PpIX to heme have limited the accumulation of PpIX, hindering the efficiency and potential application of ALA-PDT. This study aims to evaluate the PDT activity of three rationally designed series of ALA-HPO prodrugs, which were based on enhancing the lipophilicity of the prodrugs and reducing the labile iron pool (LIP) through HPO iron chelators to promote PpIX accumulation. Twenty-four ALA-HPO conjugates, incorporating amide, amino acid, and ester linkages, were synthesized. Most of the conjugates, exhibited no dark-toxicity to cells, according to bioactivity evaluation. Ester conjugates 19a-g showed promoted phototoxicity when tested on tumor cell lines, and this increased phototoxicity was strongly correlated with elevated PpIX levels. Among them, conjugate 19c emerged as the most promising (HeLa, IC50 = 24.25 ± 1.43 μM; MCF-7, IC50 = 43.30 ± 1.76 μM; A375, IC50 = 28.03 ± 1.00 μM), displaying superior photodynamic anticancer activity to ALA (IC50 > 100 μM). At a concentration of 80 μM, the fluorescence intensity of PpIX induced by compound 19c in HeLa, MCF-7, and A375 cells was 18.9, 5.3, and 2.8 times higher, respectively, than that induced by ALA. In conclusion, cellular phototoxicity showed a strong correlation with intracellular PpIX fluorescence levels, indicating the potential application of ALA-HPO conjugates in ALA-PDT.
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Study on the components changes of polysaccharides and saponins during nine steaming and drying of Polygonatum sibiricum. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2024. [PMID: 38587108 DOI: 10.1002/jsfa.13516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/26/2024] [Accepted: 04/08/2024] [Indexed: 04/09/2024]
Abstract
BACKGROUND In this study, the content and structure of Polygonatum sibiricum polysaccharides and saponins during different processing stages were determined. RESULTS After processing of Polygonatum, the content of polysaccharide and glucose decreased, and the content of galactose, glucuronic acid and sugar substitution gradually increased. The content of total saponins increased significantly. Only 18 compounds were found in raw Polygonatum and 17 new compounds were presented in processed Polygonatum. During the processing of Polygonatum, the polysaccharide was partially degraded into oligosaccharides, the molecular weight gradually decreased, and the neutral sugar was converted into uronic acid, resulting in a decrease in polysaccharide content. The saponins were partially degraded into sapogenins or modified. CONCLUSION This study clarifies the changes in the content and structure of polysaccharides and saponins in processed Polygonatum, which will pave the way for elucidating the processing mechanism. © 2024 Society of Chemical Industry.
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Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2024; 132:131802. [PMID: 38613283 DOI: 10.1103/physrevlett.132.131802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 02/26/2024] [Indexed: 04/14/2024]
Abstract
This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13 TeV and corresponding to an integrated luminosity of 137 fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst) pb.
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Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2024; 132:102301. [PMID: 38518341 DOI: 10.1103/physrevlett.132.102301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 11/07/2023] [Accepted: 12/04/2023] [Indexed: 03/24/2024]
Abstract
ATLAS measured the centrality dependence of the dijet yield using 165 nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16 TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.
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Review of studies on polysaccharides, lignins and small molecular compounds from three Polygonatum Mill. (Asparagaceae) spp. in crude and processed states. Int J Biol Macromol 2024; 260:129511. [PMID: 38242391 DOI: 10.1016/j.ijbiomac.2024.129511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 01/08/2024] [Accepted: 01/12/2024] [Indexed: 01/21/2024]
Abstract
Since ancient times, Polygonatum Mill. (Asparagaceae) has been utilized as a medicinal and culinary resource in China. Its efficacy in treating various illnesses has been well documented. Traditional processing involves the Nine-Steam-Nine-Bask method, which results in a reduction of toxicity and enhanced effectiveness of Polygonatum. Many substances, such as polysaccharides, lignins, saponins, homoisoflavones, alkaloids, and others, have been successfully isolated from Polygonatum. This review presents the research progress on the chemical composition of three crude and processed Polygonatum, including Polygonatum sibiricum Redouté (P. sibiricum), Polygonatum kingianum Collett & Hemsl (P. kingianum), and Polygonatum cyrtonema Hua (P. cyrtonema). The review also includes the pharmacology of Polygonatum, specifically on the pharmacology of polysaccharides both before and after processing. Its objective is to provide a foundation for uncovering the significance of the processing procedure, and to facilitate the development and utilization of Polygonatum in clinical practice.
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Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2024; 132:081801. [PMID: 38457710 DOI: 10.1103/physrevlett.132.081801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 12/13/2023] [Indexed: 03/10/2024]
Abstract
Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140 fb^{-1} of pp collisions at sqrt[s]=13 TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.
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Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2024; 132:021802. [PMID: 38277610 DOI: 10.1103/physrevlett.132.021802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 09/30/2023] [Accepted: 11/08/2023] [Indexed: 01/28/2024]
Abstract
This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2 fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst) fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06 fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.
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Rationale and Design of a Phase II Trial of Combined Serplulimab and Chemotherapy in Patients with Histologically Transformed Small Cell Lung Cancer: a Prospective, Single-arm and Multicentre Study. Clin Oncol (R Coll Radiol) 2024; 36:39-45. [PMID: 37977903 DOI: 10.1016/j.clon.2023.11.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023]
Abstract
AIMS Transformed small cell lung cancer (T-SCLC) is a highly aggressive clinical disease with a notably poor prognosis. It most often arises from epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) following treatment. To date, no standard treatment has been established for T-SCLC. Platinum-etoposide was the most commonly used regimen, but progression-free survival remains unsatisfactory. Therefore, there is an urgent unmet need to develop novel and effective strategies for this population. Our study, a multicentre, open-label, single-arm phase II clinical trial (NCT05957510), aims to evaluate the efficacy and safety of serplulimab plus chemotherapy in untreated T-SCLC patients after histological transformation. MATERIALS AND METHODS In total, 36 eligible participants experiencing SCLC transformation from EGFR-mutant NSCLC will be enrolled to receive combination therapy of serplulimab, etoposide and carboplatin for four to six cycles, followed by maintenance therapy with serplulimab for up to 2 years. The primary endpoint is progression-free survival; secondary endpoints include objective response rate, overall survival and safety. RESULTS Enrolment started in July 2023 and is ongoing, with an estimated completion date of December 2025. CONCLUSIONS This study aims to provide valuable insights into the efficacy and safety of combining serplulimab with chemotherapy for treating patients with T-SCLC originating from EGFR-mutant NSCLC.
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Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data. PHYSICAL REVIEW LETTERS 2023; 131:251802. [PMID: 38181336 DOI: 10.1103/physrevlett.131.251802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 11/06/2023] [Indexed: 01/07/2024]
Abstract
A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140 fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11 GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.
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Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:251801. [PMID: 38181367 DOI: 10.1103/physrevlett.131.251801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 10/11/2023] [Indexed: 01/07/2024]
Abstract
A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139 fb^{-1} of sqrt[s]=13 TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.
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Observation of Single-Top-Quark Production in Association with a Photon Using the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:181901. [PMID: 37977601 DOI: 10.1103/physrevlett.131.181901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 11/19/2023]
Abstract
This Letter reports the observation of single top quarks produced together with a photon, which directly probes the electroweak coupling of the top quark. The analysis uses 139 fb^{-1} of 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. Requiring a photon with transverse momentum larger than 20 GeV and within the detector acceptance, the fiducial cross section is measured to be 688±23(stat) _{-71}^{+75}(syst) fb, to be compared with the standard model prediction of 515_{-42}^{+36} fb at next-to-leading order in QCD.
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Author Correction: A detailed map of Higgs boson interactions by the ATLAS experiment ten years after the discovery. Nature 2023; 623:E5. [PMID: 37853131 PMCID: PMC10620074 DOI: 10.1038/s41586-023-06248-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
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Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:172301. [PMID: 37955510 DOI: 10.1103/physrevlett.131.172301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 05/11/2023] [Accepted: 09/18/2023] [Indexed: 11/14/2023]
Abstract
This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02 TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72 nb^{-1} and 257 pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158
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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings. PHYSICAL REVIEW LETTERS 2023; 131:162301. [PMID: 37925689 DOI: 10.1103/physrevlett.131.162301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/18/2023] [Accepted: 08/09/2023] [Indexed: 11/07/2023]
Abstract
A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13 TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8 pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.
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Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:151902. [PMID: 37897770 DOI: 10.1103/physrevlett.131.151902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/31/2023] [Accepted: 08/11/2023] [Indexed: 10/30/2023]
Abstract
A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13 TeV, corresponding to an integrated luminosity of 140 fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.
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Observation of the γγ→ττ Process in Pb+Pb Collisions and Constraints on the τ-Lepton Anomalous Magnetic Moment with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:151802. [PMID: 37897746 DOI: 10.1103/physrevlett.131.151802] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 07/07/2022] [Indexed: 10/30/2023]
Abstract
This Letter reports the observation of τ-lepton-pair production in ultraperipheral lead-lead collisions Pb+Pb→Pb(γγ→ττ)Pb and constraints on the τ-lepton anomalous magnetic moment a_{τ}. The dataset corresponds to an integrated luminosity of 1.44 nb^{-1} of LHC Pb+Pb collisions at sqrt[s_{NN}]=5.02 TeV recorded by the ATLAS experiment in 2018. Selected events contain one muon from a τ-lepton decay, an electron or charged-particle track(s) from the other τ-lepton decay, little additional central-detector activity, and no forward neutrons. The γγ→ττ process is observed in Pb+Pb collisions with a significance exceeding 5 standard deviations and a signal strength of μ_{ττ}=1.03_{-0.05}^{+0.06} assuming the standard model value for a_{τ}. To measure a_{τ}, a template fit to the muon transverse-momentum distribution from τ-lepton candidates is performed, using a dimuon (γγ→μμ) control sample to constrain systematic uncertainties. The observed 95% confidence-level interval for a_{τ} is -0.057
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A high activity mesoporous Pt@KIT-6 nanocomposite for selective hydrogenation of halogenated nitroarenes in a continuous-flow microreactor. NANOSCALE ADVANCES 2023; 5:5649-5660. [PMID: 37822898 PMCID: PMC10563833 DOI: 10.1039/d3na00437f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 09/13/2023] [Indexed: 10/13/2023]
Abstract
In this study, we designed a Pt@KIT-6 nanocomposite prepared by impregnating platinum nanoparticles on the nanopores of the KIT-6 mesoporous material. This Pt@KIT-6 nanocomposite was used as a catalyst in a micro fixed bed reactor (MFBR) for the continuous-flow hydrogenation of halogenated nitroarenes, which demonstrates three advantages. First, the Pt@KIT-6 nanocomposite has a stable mesoporous nanostructure, which effectively enhances the active site and hydrogen adsorption capacity. The uniformly distributed pore structure and large specific surface area were confirmed by electron microscopy and N2 physisorption, respectively. In addition, the aggregation of the loaded metal was avoided, which facilitated the maintenance of high activity and selectivity. The conversion and selectivity reached 99% within 5.0 minutes at room temperature (20 °C). Furthermore, the continuous-flow microreactor allows precise control and timely transfer of the reaction system, reducing the impact of haloid acids. The activity and selectivity of the Pt@KIT-6 nanocomposite showed virtually no degradation after 24 hours of continuous operation of the entire continuous-flow system. Overall, the Pt@KIT-6 nanocomposite showed good catalysis for the hydrogenation of halogenated nitroarenes in the continuous-flow microreactor. This work provides insights into the rational design of a highly active and selective catalyst for selective hydrogenation systems.
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Mechanochemical synthesis of cysteine-gum acacia intermolecular complex for multiple metal(loid) sequestration from herbal extracts. CHEMOSPHERE 2023; 338:139612. [PMID: 37482312 DOI: 10.1016/j.chemosphere.2023.139612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 07/17/2023] [Accepted: 07/21/2023] [Indexed: 07/25/2023]
Abstract
The ubiquitous heavy metal(loid)s (HMs) contamination has triggered great concern about food safety, while sequestration and separation of trace HMs from herbal extracts still calls for appropriate sorbent materials. In this work, gum acacia was modified by cysteine to form a cysteine-acacia intermolecular complex (Cys-GA complex) via facile mechanochemical synthesis, aiming at capturing multiple HMs simultaneously. Preliminary screening confirms the superiority of Cys-CA complex for both cationic and anionic HMs, and determines an optimum Cys/GA mass ratio of 9:1 to achieve high removal capacities for Pb(II) (938 mg g-1), Cd(II) (834 mg g-1), As(V) (496 mg g-1), and Cr(VI) (647 mg g-1) in simulated aqueous solution. The analysis on HMs-exhausted Cys-GA complex indicates that Pb(II), As(V), and Cr(VI) tend to be removed through chelation, electrostatic attraction, and reduction, while Cd(II) can only be chelated or adsorbed by electrostatic interaction. The batch experiments on commercial herbal (e.g. Panax ginseng, Glycine max, Sophora flavescens, Gardenia jasminoides, Cyclocarya paliurus, and Bamboo leaf) extracts indicate that Cys-GA complex can reduce HMs concentration to attain acceptable level that comply with International Organization for Standardization, with negligible negative effect on its active ingredients. This work provides a practical and convenient strategy to purify HMs-contaminated foods without introducing secondary pollution.
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Universal response method for the quantitative analysis of photodegradation impurities in lomefloxacin hydrochloride ear drops by liquid chromatography coupled with charged aerosol detector. J Pharm Biomed Anal 2023; 234:115552. [PMID: 37393690 DOI: 10.1016/j.jpba.2023.115552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/11/2023] [Accepted: 06/25/2023] [Indexed: 07/04/2023]
Abstract
In terms of risk assessment especially for the impurities with different ultraviolet responses, quantitative analysis without the availability of corresponding reference substances currently poses a challenge. In this study, a universal response method was established for the quantitative analysis of photodegradable impurities in lomefloxacin hydrochloride ear drops by high performance liquid chromatography-charged aerosol detector (HPLC-CAD) for the first time. The chromatographic conditions and CAD parameters were optimized for a good separation and sensitivity. The uniform response of developed method was validated by impurity reference substances with different ultraviolet responses. In the gradient compensation HPLC-CAD method validation, good linearities were obtained with coefficient of determination (R2) all greater than 0.999 for lomefloxacin and impurity reference substances. The average recoveries of the impurities were 98.63%- 102.18% by UV and 97.92%- 102.57% by CAD, respectively. RSDs all were less than 2.5% for intra-day and inter-day precision by UV and CAD, with good precision and accuracy. The correction factor experimental results showed that the developed method provided a uniform response to the impurities with differences chromophores in lomefloxacin. The effects of packaging materials and excipients on the photodegradation were also investigated using the developed method. The results of correlation analysis showed that the packaging materials with low light transmittance and the organic excipients (glycerol and ethanol) could significantly improve the stability of lomefloxacin hydrochloride ear drops. The developed HPLC-CAD quantification method was a reliable and universal response method for quantitative analysis of impurities in the lomefloxacin. This study also revealed the key factors affecting the photodegradation of lomefloxacin hydrochloride ear drops, which guided enterprises to improve drug prescription and packaging materials and ensure the public medication safety.
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Ethics and biomedical engineering for well-being: a cocreation study of remote services for monitoring and support. Sci Rep 2023; 13:14322. [PMID: 37652901 PMCID: PMC10471689 DOI: 10.1038/s41598-023-39834-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 07/31/2023] [Indexed: 09/02/2023] Open
Abstract
The well-being of students and staff directly affects their output and efficiency. This study presents the results of two focus groups conducted in 2022 within a two-phase project led by the Applied Biomedical and Signal Processing Intelligent e-Health Lab, School of Engineering at the University of Warwick, and British Telecom within "The Connected Campus: University of Warwick case study" program. The first phase, by involving staff and students at the University of Warwick, aimed at collecting preliminary information for the subsequent second phase, about the feasibility of the use of Artificial Intelligence and Internet of Things for well-being support on Campus. The main findings of this first phase are interesting technological suggestions from real users. The users helped in the design of the scenarios and in the selection of the key enabling technologies which they considered as the most relevant, useful and acceptable to support and improve well-being on Campus. These results will inform future services to design and implement technologies for monitoring and supporting well-being, such as hybrid, minimal and even intrusive (implantable) solutions. The user-driven co-design of such services, leveraging the use of wearable devices and Artificial Intelligence deployment will increase their acceptability by the users.
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Strong Constraints on Jet Quenching in Centrality-Dependent p+Pb Collisions at 5.02 TeV from ATLAS. PHYSICAL REVIEW LETTERS 2023; 131:072301. [PMID: 37656838 DOI: 10.1103/physrevlett.131.072301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 10/04/2022] [Accepted: 11/17/2022] [Indexed: 09/03/2023]
Abstract
Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including pp and p+Pb collisions. In contrast, while jet quenching is observed in Pb+Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36 nb^{-1} of p+Pb and 3.6 pb^{-1} of pp collisions at 5.02 TeV. The yields of charged hadrons with p_{T}^{ch}>0.5 GeV near and opposite in azimuth to jets with p_{T}^{jet}>30 or 60 GeV, and the ratios of these yields between p+Pb and pp collisions, I_{pPb}, are reported. The collision centrality of p+Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The I_{pPb} values are consistent with unity within a few percent for hadrons with p_{T}^{ch}>4 GeV at all centralities. These data provide new, strong constraints that preclude almost any parton energy loss in central p+Pb collisions.
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Search for Heavy Neutral Leptons in Decays of W Bosons Using a Dilepton Displaced Vertex in sqrt[s]=13 TeV pp Collisions with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:061803. [PMID: 37625051 DOI: 10.1103/physrevlett.131.061803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 08/08/2022] [Indexed: 08/27/2023]
Abstract
A search for a long-lived, heavy neutral lepton (N) in 139 fb^{-1} of sqrt[s]=13 TeV pp collision data collected by the ATLAS detector at the Large Hadron Collider is reported. The N is produced via W→Nμ or W→Ne and decays into two charged leptons and a neutrino, forming a displaced vertex. The N mass is used to discriminate between signal and background. No signal is observed, and limits are set on the squared mixing parameters of the N with the left-handed neutrino states for the N mass range 3 GeV
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Test of CP Invariance in Higgs Boson Vector-Boson-Fusion Production Using the H→γγ Channel with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2023; 131:061802. [PMID: 37625052 DOI: 10.1103/physrevlett.131.061802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 02/03/2023] [Indexed: 08/27/2023]
Abstract
A test of CP invariance in Higgs boson production via vector-boson fusion has been performed in the H→γγ channel using 139 fb^{-1} of proton-proton collision data at sqrt[s]=13 TeV collected by the ATLAS detector at the LHC. The optimal observable method is used to probe the CP structure of interactions between the Higgs boson and electroweak gauge bosons, as described by an effective field theory. No sign of CP violation is observed in the data. Constraints are set on the parameters describing the strength of the CP-odd component in the coupling between the Higgs boson and the electroweak gauge bosons in two effective field theory bases: d[over ˜] in the HISZ basis and c_{HW[over ˜]} in the Warsaw basis. The results presented are the most stringent constraints on CP violation in the coupling between Higgs and weak bosons. The 95% C.L. constraint on d[over ˜] is derived for the first time and the 95% C.L. constraint on c_{HW[over ˜]} has been improved by a factor of 5 compared to the previous measurement.
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Study on the impurity profile and influencing factors of photodegradation in non-aqueous ofloxacin ear drops using liquid chromatography combined with ion trap/time-of-flight mass spectrometry. J Pharm Biomed Anal 2023; 233:115476. [PMID: 37245330 DOI: 10.1016/j.jpba.2023.115476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/15/2023] [Accepted: 05/20/2023] [Indexed: 05/30/2023]
Abstract
Ofloxacin ear drops contain a large proportion of organic solvents, which have a great effect on the photodegradation of ofloxacin. The photodegradation impurities of ofloxacin in aqueous solution has been studied, however, the photodegradation of ofloxacin in non-aqueous solution with a high proportion of organic solvents has not been reported. In this article, the impurity profile in non-aqueous ofloxacin ear drops was studied for further improvement of official monograph in pharmacopoeia and quality control of drug. The liquid chromatography combined with ion trap/time-of-flight mass spectrometry was applied to separate and characterize the structures of the impurities in non-aqueous ofloxacin ear drops. Mass fragmentation pattern of ofloxacin and its impurities were studied. The structures of seventeen impurities in ofloxacin ear drops were elucidated based on the high-resolution MSn data in positive ion modes, and ten of them were unknown impurities. The results showed that the impurity profile of non-aqueous ofloxacin solution was significantly different from that of aqueous ofloxacin solution. The effects of packaging materials and excipients on the photodegradation of ofloxacin ear drops were also investigated. The results of correlation analysis showed that the packaging materials with low light transmittance could reduce the light degradation, and ethanol of excipients could significantly decrease the light stability of ofloxacin ear drops. This study revealed the impurity profile and key factors affecting the photodegradation of non-aqueous ofloxacin ear drops, and guided enterprises to improve drug prescription and packaging materials to ensure the safety of drug use by the public.
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Improving the Treatment Effect of Carotenoids on Alzheimer's Disease through Various Nano-Delivery Systems. Int J Mol Sci 2023; 24:ijms24087652. [PMID: 37108814 PMCID: PMC10142927 DOI: 10.3390/ijms24087652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/10/2023] [Accepted: 04/20/2023] [Indexed: 04/29/2023] Open
Abstract
Natural bioactive compounds have recently emerged as a current strategy for Alzheimer's disease treatment. Carotenoids, including astaxanthin, lycopene, lutein, fucoxanthin, crocin and others are natural pigments and antioxidants, and can be used to treat a variety of diseases, including Alzheimer's disease. However, carotenoids, as oil-soluble substances with additional unsaturated groups, suffer from low solubility, poor stability and poor bioavailability. Therefore, the preparation of various nano-drug delivery systems from carotenoids is a current measure to achieve efficient application of carotenoids. Different carotenoid delivery systems can improve the solubility, stability, permeability and bioavailability of carotenoids to a certain extent to achieve Alzheimer's disease efficacy. This review summarizes recent data on different carotenoid nano-drug delivery systems for the treatment of Alzheimer's disease, including polymer, lipid, inorganic and hybrid nano-drug delivery systems. These drug delivery systems have been shown to have a beneficial therapeutic effect on Alzheimer's disease to a certain extent.
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C-4 Regioselective Alkylation of Pyridines Driven by Mechanochemically Activated Magnesium Metal. Org Lett 2023; 25:2531-2536. [PMID: 37018037 DOI: 10.1021/acs.orglett.3c00684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2023]
Abstract
Mechanochemically activated magnesium(0) metal as a highly active mediator driving direct C-4-H alkylation of pyridines with alkyl halides has been developed. Excellent regioselectivity and substrate scope, including those containing reducible functionalities, free amines, and alcohols, as well as biologically relevant molecules were achieved to access 4-alkylpyridine products. Preliminary mechanistic studies suggested a radical-radical coupling pathway.
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Continuous-Flow Hydrogenation of Nitroaromatics in Microreactor with Mesoporous Pd@SBA-15. Processes (Basel) 2023. [DOI: 10.3390/pr11041074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
Abstract
The hydrogenation of nitroaromatics to prepare aromatic amines plays a crucial role in the chemical industry. Traditional hydrogenation has the risk of hydrogen leakage from the equipment, and its catalyst has the disadvantage of being easily deactivated and difficult to recover. In this study, we designed an efficient and stable mesoporous catalyst, Pd@SBA-15, which was constructed by impregnating the nanopores of the mesoporous material SBA-15 with palladium nanoparticles. The catalyst was then filled in a micro-packed-bed reactor (MPBR) for continuous flow hydrogenation. The designed continuous flow hydrogenation system has two distinctive features. First, we used mesoporous Pd@SBA-15 instead of the traditional bulk Pd/C as the hydrogenation catalyst, which is more suitable for exposing the active sites of metal Pd and reducing the agglomeration of nanometals. The highly ordered porous structure enhances hydrogen adsorption and thus hydrogenation efficiency. Secondly, the continuous flow system allows for precise detection and control of the reaction process. The highly efficient catalysts do not require complex post-treatment recovery, which continues to operate for 24 h with barely any reduction in activity. Due to the high catalytic activity, the designed mesoporous Pd@SBA-15 showed excellent catalytic performance as a hydrogenation catalyst in a continuous flow system with 99% conversion of nitroaromatics in 1 min. This work provides insights into the rational design of hydrogenation systems in the chemical industry.
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Determination of elemental impurities in lomefloxacin hydrochloride ear drops by inductively coupled plasma-mass spectrometry using oxygen reaction mode and study of their catalytic effect on photodegradation reaction. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2023; 37:e9468. [PMID: 36597261 DOI: 10.1002/rcm.9468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/28/2022] [Accepted: 01/01/2023] [Indexed: 06/17/2023]
Abstract
RATIONALE This study developed a method for the simultaneous determination of 12 element impurities in lomefloxacin hydrochloride ear drops using inductively coupled plasma-mass spectrometry (ICP-MS) in accordance with the requirements of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use Q3D. However, this product contains high concentrations of organic compounds such as glycerol and ethanol, and soluble carbon interference exists when it is determined by direct injection method. Therefore, we applied ICP-MS using oxygen reaction mode to reduce the effect of high organic matter on plasma body. The catalytic effect of trace metal ions on the photodegradation of lomefloxacin hydrochloride was also investigated. METHODS The sample was dissolved, diluted, and directly determined by direct injection using oxygen reaction mode of ICP-MS with 45 Sc, 73 Ge, and 115 In as internal standards. Direct injection using oxygen reaction mode was equipped with argon-oxygen mixer. To investigate the catalytic effect of metal ions on photodegradation, a series of combinations of lomefloxacin hydrochloride mixed with different metal ions were designed. After being irradiated under ultraviolet light for 10 days, the photodegraded impurities in combinations were determined using high-performance liquid chromatography. RESULTS The linear relationships in the corresponding concentration range for 12 element impurities were good (r > 0.9993). Limits of detection were between 0.002 and 1.294 ng ml-1 . The average recoveries were 93.7%-108.2%, and the precision relative standard deviation was 0.04%-0.55% (n = 6). The experimental results showed that metal ions had a certain catalytic effect on photodegradation of lomefloxacin when EDTA, Mg2+ , and Cu2+ coexisted. CONCLUSIONS ICP-MS using oxygen reaction mode is suitable for the direct determination of the sample rich in organic matter without digestion and can effectively eliminate the interference of high organic matter in this product. The established method was rapid, sensitive, and accurate and can be used for the quality control of elemental impurities in lomefloxacin hydrochloride ear drops.
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An Efficient Continuous Flow Synthesis for the Preparation of N-Arylhydroxylamines: Via a DMAP-Mediated Hydrogenation Process. Molecules 2023; 28:molecules28072968. [PMID: 37049731 PMCID: PMC10096002 DOI: 10.3390/molecules28072968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/23/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
The selective hydrogenation of nitroarenes to N-arylhydroxylamines is an important synthetic process in the chemical industry. It is commonly accomplished by using heterogeneous catalytic systems that contain inhibitors, such as DMSO. Herein, DMAP has been identified as a unique additive for increasing hydrogenation activity and product selectivity (up to >99%) under mild conditions in the Pt/C-catalyzed process. Continuous-flow technology has been explored as an efficient approach toward achieving the selective hydrogenation of nitroarenes to N-arylhydroxylamines. The present flow protocol was applied for a vast substrate scope and was found to be compatible with a wide range of functional groups, such as electron-donating groups, carbonyl, and various halogens. Further studies were attempted to show that the improvement in the catalytic activity and selectivity benefited from the dual functions of DMAP; namely, the heterolytic H2 cleavage and competitive adsorption.
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NMR-Based Metabolomics to Analyze the Effects of a Series of Monoamine Oxidases-B Inhibitors on U251 Cells. Biomolecules 2023; 13:biom13040600. [PMID: 37189348 DOI: 10.3390/biom13040600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 03/29/2023] Open
Abstract
Alzheimer’s disease (AD) is a typical progressive neurodegenerative disorder, and with multiple possible pathogenesis. Among them, coumarin derivatives could be used as potential drugs as monoamine oxidase-B (MAO-B) inhibitors. Our lab has designed and synthesized coumarin derivatives based on MAO-B. In this study, we used nuclear magnetic resonance (NMR)-based metabolomics to accelerate the pharmacodynamic evaluation of candidate drugs for coumarin derivative research and development. We detailed alterations in the metabolic profiles of nerve cells with various coumarin derivatives. In total, we identified 58 metabolites and calculated their relative concentrations in U251 cells. In the meantime, the outcomes of multivariate statistical analysis showed that when twelve coumarin compounds were treated with U251cells, the metabolic phenotypes were distinct. In the treatment of different coumarin derivatives, there several metabolic pathways changed, including aminoacyl-tRNA biosynthesis, D-glutamine and D-glutamate metabolism, glycine, serine and threonine metabolism, taurine and hypotaurine metabolism, arginine biosynthesis, alanine, aspartate and glutamate metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, glutathione metabolism and valine, leucine and isoleucine biosynthesis. Our work documented how our coumarin derivatives affected the metabolic phenotype of nerve cells in vitro. We believe that these NMR-based metabolomics might accelerate the process of drug research in vitro and in vivo.
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[Clinical and genetic characteristics of young patients with myeloproliferative neoplasms]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2023; 44:193-201. [PMID: 37356980 PMCID: PMC10119718 DOI: 10.3760/cma.j.issn.0253-2727.2023.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
Objectives: To investigate the clinical and genetic features of young Chinese patients with myeloproliferative neoplasms (MPN). Methods: In this cross-sectional study, anonymous questionnaires were distributed to patients with MPN patients nationwide. The respondents were divided into 3 groups based on their age at diagnosis: young (≤40 years) , middle-aged (41-60 years) , and elderly (>60 years) . We compared the clinical and genetic characteristics of three groups of MPN patients. Results: 1727 assessable questionnaires were collected. There were 453 (26.2%) young respondents with MPNs, including 274 with essential thrombocythemia (ET) , 80 with polycythemia vera (PV) , and 99 with myelofibrosis. Among the young group, 178 (39.3%) were male, and the median age was 31 (18-40) years. In comparison to middle-aged and elderly respondents, young respondents with MPN were more likely to present with a higher proportion of unmarried status (all P<0.001) , a higher education level (all P<0.001) , less comorbidity (ies) , fewer medications (all P<0.001) , and low-risk stratification (all P<0.001) . Younger respondents experienced headache (ET, P<0.001; PV, P=0.007; MF, P=0.001) at diagnosis, had splenomegaly at diagnosis (PV, P<0.001) , and survey (ET, P=0.052; PV, P=0.063) . Younger respondents had fewer thrombotic events at diagnosis (ET, P<0.001; PV, P=0.011) and during the survey (ET, P<0.001; PV, P=0.003) . JAK2 mutations were found in fewer young people (ET, P<0.001; PV, P<0.001; MF, P=0.013) ; however, CALR mutations were found in more young people (ET, P<0.001; MF, P=0.015) . Furthermore, mutations in non-driver genes (ET, P=0.042; PV, P=0.043; MF, P=0.004) and high-molecular risk mutations (ET, P=0.024; PV, P=0.023; MF, P=0.001) were found in fewer young respondents. Conclusion: Compared with middle-aged and elderly patients, young patients with MPN had unique clinical and genetic characteristics.
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Differentiation of tetracyclines and their 4-epimers by mass spectrometry of the alkali metal adduct ions. Talanta 2023; 254:124201. [PMID: 36549141 DOI: 10.1016/j.talanta.2022.124201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/14/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022]
Abstract
Tetracyclines (TCs) are a family of broad-spectrum antibiotics. During the manufacturing process or storage, epimerization of tetracyclines could occur, leading to 4-epimers which are nearly inactive. From an analytical point of view, isomers are often difficult to distinguish. Previously, four pairs of TCs (oxytetracycline, tetracycline, doxycycline, chlortetracycline and their respective 4-epimers) were differentiated by mass spectrometry (MS) through protonated ions. However, they do not follow common rules and so it is still quite difficult to differentiate between them. In order to solve this, the four pairs were differentiated in the current study by collision induced dissociation (CID) spectra of the alkali adduct ions, including lithium, sodium and potassium. In the spectra of the sodium adducts, all studied tetracyclines showed a tendency to form [M+Na-NH3]+ ions, while the 4-epimers liked to form [M+Na-NH3-H2O]+ ions. Meanwhile, energy resolved mass spectrometry (ERMS) showed that all four 4-epimers' sodium adducts had the tendency to fragment at higher energy points. In the CID spectra of lithium adducts of TCs, a similar trend was observed for three pairs, except for doxycycline. For potassium adducts, the fragmentation was found to be less discriminative. As was derived from the 3D model, the four pairs all interact with the alkali metal through the dimethyl amino group at the C-4 position. The lithium adduct species also bound through the hydroxyl group at the C-5 position. If the TCs did not have a hydroxyl group at the C-5 position, they bound with the hydroxyl group at the C-6 position. For the same TC, with an increase of the diameter of the metal ion, the loss of H2O decreased gradually. As sodium adduct ions are common during the ionization process, TCs and their 4-epimers could be differentiated rapidly by ERMS of the sodium adduct ions.
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[Clinical characteristics and progression risk factors for patients with monoclonal gammopathy of undetermined significance]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2023; 44:137-140. [PMID: 36948868 PMCID: PMC10033275 DOI: 10.3760/cma.j.issn.0253-2727.2023.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/24/2023]
Abstract
Objective: To analyze the clinical presentation and progression risk factors of patients with monoclonal gammopathy of undetermined significance (MGUS) in China. Methods: We retrospectively assessed the clinical features and disease progression of 1 037 patients with monoclonal gammopathy of undetermined significance between January 2004 and January 2022 at Peking Union Medical College Hospital. Results: A total of 1 037 patients were recruited in the study, including 636 males (63.6%) , with a median age of 58 (18-94) years. The median concentration of serum monoclonal protein was 2.7 (0-29.4) g/L. The monoclonal immunoglobulin type was IgG in 380 patients (59.7%) , IgA in 143 patients (22.5%) , IgM in 103 patients (16.2%) , IgD in 4 patients (0.6%) , and light chain in 6 patients (0.9%) . 171 patients (31.9%) had an abnormal serum-free light chain ratio (sFLCr) . According to the Mayo Clinic model for risk of progression, the proportion of patients in the low-risk, medium-low-risk, medium-high risk, and high-risk groups were 254 (59.5%) , 126 (29.5%) , 43 (10.1%) , and 4 (0.9%) , respectively. With a median follow-up of 47 (1-204) months, 34 of 795 patients (4.3%) had disease progression, and 22 (2.8%) died. The overall progression rate was 1.06 (0.99-1.13) /100 person-years. Patients with non-IgM MGUS have a markedly higher disease progression rate per 100 person-years than IgM-MGUS (2.87/100 person-years vs 0.99/100 person-years, P=0.002) . The disease progression rate per 100 person-years in non-IgM-MGUS patients of Mayo classification low-risk, medium-low risk and medium-high risk groups were 0.32 (0.25-0.39) /100 person-years, 1.82 (1.55-2.09) /100 person-years, and2.71 (1.93-3.49) /100 person-years, which had statistically difference (P=0.005) . Conclusion: In comparison to non-IgM-MGUS, IgM-MGUS has a greater risk of disease progression. The Mayo Clinic progression risk model applies to non-IgM-MGUS patients in China.
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Metal-free regioselective mono- and poly-halogenation of 2-substituted indazoles. RSC Adv 2023; 13:4958-4962. [PMID: 36762091 PMCID: PMC9904359 DOI: 10.1039/d2ra07398f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 01/04/2023] [Indexed: 02/10/2023] Open
Abstract
An unprecedented metal-free regioselective halogenation of 2H-indazoles has been revealed, which not only realized the highly selective synthesis of mono-halogenated products, but also completed poly-halogenations by fine tuning the reaction conditions. Various mono-/poly-/hetero-halogenated indazoles were obtained in moderate to excellent yields. Notably, this approach features environmentally friendly solvents, mild reaction conditions, simple execution and short reaction time.
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Analysis of organic components in various butyl rubber closures and their compatibility study with cefamandole nafate by HPLC/GC-MS. CURR PHARM ANAL 2023. [DOI: 10.2174/1573412919666230202153741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Background:
To control the quality of various butyl rubber closures and assess their applicability to cefamandole nafate, HPLC/ GC-MS methods were developed to qualitatively and quantitatively analyze the organic components in various types of butyl rubber closures and drug powder of cefamandole nafate for injection, and migration of these components from rubber closures to drug also were studied.
background:
To control the quality of various butyl rubber closures and assess their applicability to cefamandole nafate, HPLC/ GC-MS methods were developed to qualitatively and quantitatively analyze the organic components in various types of butyl rubber closures and drug powder of cefamandole nafate for injection, and migration of these components from rubber closures to drug also were studied.
Materials and Methods:
The chemical components in the rubber closures and corresponding drug were identified by GC-MS in full scan mode and NIST mass library. A GC-MS method in SIM mode was established to quantitatively analyze siloxane compounds, aromatic hydrocarbons and saturated chain-hydrocarbons in rubber closures and drugs. An HPLC method was established to quantitatively analyze antioxidants and sulfides from rubber closures and drugs. The turbidity values of powder for injection were measured by a turbidimeter. Further, the correlation between the content of organic components in the drug and the clarity of the solution was analyzed.
objective:
To control the quality of various butyl rubber closures and assess their applicability to cefamandole nafate
Results:
It was found that the chemical components were released from butyl rubber closures and migrated to the drug, which influenced solution clarity of cefamandole nafate for injection and was the main factor to cause solution turbidity of powder for injection. The gradual migration of components occurred over time with the use of common butyl rubber closures, but the coated butyl rubber closures (rubber plated with membrane) were coated with a polytetrafluoroethylene film to block the contact between rubber closures and the drug, and could effectively prevent the migration of the components from rubber closures to drugs. The organic components in the butyl rubber closures were mainly identified as siloxanes, saturated chain-hydrocarbons, and antioxidants. An unknown ingredient was identified as 1-piperidinecarboxaldehyde, and trace amounts of toxic toluene were also detected within limits.
method:
The chemical components in the rubber closures and corresponding drug were identified by GC-MS in full scan mode and NIST mass library. A GC-MS method in SIM mode was established to quantitatively analyzed siloxane compounds, aromatic hydrocarbons and saturated chain-hydrocarbons in rubber closures and drugs. A HPLC method was established to quantitatively analyze antioxidants and sulfides from rubber closures and drugs. The turbidity values of powder for injection were measured by turbidimeter. Further, the correlation between the content of organic component in the drug and the clarity of solution was analyzed.
Conclusion:
It is suggested that rubber plated with membrane or rubber closures of high quality were applicable to cefamandole nafate for injection and should be used in its production. HPLC/ GC-MS methods can be used as an effective method for quality control of butyl rubber closures and compatibility research with drugs to ensure drug safety for the public.
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High efficiently preparation of cellulose nanocrystals by mechano-enzymatic hydrolysis: the mechanism study. Catal Sci Technol 2023. [DOI: 10.1039/d2cy01904c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
One-step mechano-enzymatic hydrolysis (MEH) method was developed to prepare cellulose nanocrystals (CNCs) under liquid-assited grinding (LAG) conditions. The mechanism of MEH to afford high yields of CNCs was elucidated that...
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Regioselective Benzylation of Quinoxalin‐2(1H)‐ones with Methylarenes Under Transition‐Metal‐Free Conditions. ChemistrySelect 2022. [DOI: 10.1002/slct.202203468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Efficacy and safety of native type II collagen in modulating knee osteoarthritis symptoms: a randomised, double-blind, placebo-controlled trial. J Exp Orthop 2022; 9:123. [PMID: 36562843 PMCID: PMC9780623 DOI: 10.1186/s40634-022-00559-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 11/30/2022] [Indexed: 12/24/2022] Open
Abstract
PURPOSE Knee osteoarthritis (OA) is the most common form of clinical arthritis in middle-aged and older individuals. Undenatured or native type II (TII) collagen derived from the chicken sternum has a good therapeutic effect on relieving severe pain of OA. Hence, the present study aimed to investigate the efficacy and safety of TII collagen (Native CT-II®) in individuals with knee OA. METHODS We conducted a 12-week randomised, double-blind, placebo-controlled, parallel-group study on 101 participants aged 40-65 years with knee OA. The participants were randomised to receive either TII collagen, glucosamine hydrochloride + chondroitin sulfate (G + C) or a placebo. The primary outcome was an improvement in the joint health of the participants assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) compared to G + C and placebo. RESULTS Compared with the placebo group (n = 27), the TII collagen group (n = 29) and G + C group (n = 29) significantly improved the overall joint health measured by the change in WOMAC total score (week 12: TII collagen = -32.47 ± 19.51 and G + C = -33.74 ± 24.64 vs. placebo = -13.84 ± 17.61; p < 0.05) and relieved knee joint pain (week 12: TII collagen = -5.69 ± 3.66 and G + C = -6.03 ± 4.72 vs. placebo = -2.71 ± 3.95; p < 0.05). The statistically significant effect was observed as early as 4 weeks after the investigational product administration. Additionally, the TII collagen was more effective in improving the quality of life than the G + C. CONCLUSION TII collagen not only has a significantly better effect and high safety profile for OA but also improves the quality of life of patients. LEVEL OF EVIDENCE Level 1 - Randomized Controlled Trial. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT04470336 ; First submitted date: July 08, 2020; First posted date: July 14, 2020.
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A Multi-Institutional Study of Definitive Radiotherapy for Locally Advanced Basal Cell Carcinoma. Int J Radiat Oncol Biol Phys 2022. [DOI: 10.1016/j.ijrobp.2022.07.1809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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A Phase II Study of Nelfinavir plus Concurrent Chemoradiation for Advanced, HPV-Negative Squamous Cell Carcinoma of the Head and Neck. Int J Radiat Oncol Biol Phys 2022. [DOI: 10.1016/j.ijrobp.2022.07.613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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9P Development and validation of a pathogenomics model to improve the risk stratification of breast cancer: A deep learning study. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.10.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
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[Prognostic value of translocation t(11;14) in primary light-chain amyloidosis treated with bortezomib-based regimen]. ZHONGHUA YI XUE ZA ZHI 2022; 102:2854-2860. [PMID: 36153870 DOI: 10.3760/cma.j.cn112137-20211227-02908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To investigate the prognostic value of translocation t(11;14) in newly-diagnosed primary light-chain (AL) amyloidosis patients treated with bortezomib-based regimen. Method: Clinical information of newly-diagnosed AL amyloidosis patients in Peking Union Medical College Hospital who had baseline t(11;14) data and accepted bortezomib-combined therapies from September, 2015 to September, 2021 was collected. The relationships between t(11;14) status and baseline characteristics, hematological response, organ response and prognosis were analyzed. Results: A total of 152 patients were included, aged (59.5±9.1) years and 93 cases were male (61.2%). Forty-six patients carried t(11;14) (30.3%). There was no statistical difference in the proportion of organ involved, distribution of Mayo 2004 and 2012 stages and laboratory indexes between patients with and without t(11;14) (all P>0.05). For hematological response, the difference in the rates of ≥very good partial response (VGPR) between those with t(11;14) and without after the first cycle [28.2%(11/39) vs 37.4%(34/91), P>0.05] was not statistically significant. After 3 cycles, the difference in the rates of ≥VGPR between two groups was not statistically significant [35.9%(14/39) vs 51.1%(46/90), P>0.05]. The difference in the ratio of the best hematological response reaching ≥VGPR between two groups during the first-line treatment was not statistically significant [52.2%(24/46) vs 64.2%(68/106), P>0.05]. But patients with t(11;14) had lower cardiac response rate at 3 months [15.2%(5/33) vs 34.6%(28/81), P=0.038] and 6 months [19.4%(6/31) vs 50.6%(42/83),P=0.003] than those without, but the difference in cardiac response rates at 12 months was not statistically significant [41.7%(10/24) vs 53.5%(38/71),P>0.05]. For survival, the differences in overall survival (not reached vs 50.1 months, P>0.05) and hematological event-free survival (36.2 months vs 39.9 months, P>0.05) between patients carrying t(11;14) and those without were not statistically significant. Conclusion: Patients with t(11;14) had lower cardiac response rate than those without, but their hematological response and survival are not significantly different from those free from t(11;14).
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896P Multiple radiomic biomarkers-based machine learning model to predict responses of surufatinib-treated advanced neuroendocrine tumor (NET): A multicenter exploratory study. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.07.1022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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EP08.02-063 SANOVO: A Phase 3 Study of Savolitinib or Placebo in Combination with Osimertinib in Patients with EGFR-mutant and MET Overexpressed NSCLC. J Thorac Oncol 2022. [DOI: 10.1016/j.jtho.2022.07.745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Design and biological features of platinum (II) complexes with 3-hydroxy-3-(Trifluoromethyl)cyclobutane-1,1-Dicarboxylate as a leaving ligand. Eur J Med Chem 2022; 242:114673. [PMID: 36049275 DOI: 10.1016/j.ejmech.2022.114673] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 08/06/2022] [Accepted: 08/08/2022] [Indexed: 11/04/2022]
Abstract
A series of platinum compounds 2a-5a and 2b-5b with fluoro-functional groups are designed and synthesized. Among them, complex 2b is the most effective agent with 3-hydroxy-3-(trifluoromethyl)cyclobutane-1,1-dicarboxylate as a leaving ligand, which showed better cytotoxic activity than compounds containing only CF3 or OH group at 3-position of cyclobutane-1,1-dicarboxylate. The water solubility of 2a is better than that of carboplatin (32 mg/mL vs. 16 mg/mL), and its antitumor activity on A549 is 4.6-fold higher than that of carboplatin. The IC50 value of 2b on A549 cells is 4.73 ± 0.64 μM, which is comparable to that of oxaliplatin and higher than that of carboplatin. Meanwhile, 2a and 2b are less toxic than oxaliplatin and cisplatin toward BEAS-2B cells. Moreover, 2a and 2b induce cell apoptosis in vitro by the Bax-Bcl-2-caspase-3 pathway and ferroptosis through inhibiting GPx-4 and elevating COX2. Results from in vivo experiment show that the inhibition rate of A549 xenograft tumor is cisplatin > 2b > oxaliplatin > 2a > carboplatin.
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Modular reconstruction and optimization of the trans-4-hydroxy-L-proline synthesis pathway in Escherichia coli. Microb Cell Fact 2022; 21:159. [PMID: 35953819 PMCID: PMC9367115 DOI: 10.1186/s12934-022-01884-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 07/26/2022] [Indexed: 11/24/2022] Open
Abstract
Background In recent years, there has been a growing demand for microbial production of trans-4-hydroxy-L-proline (t4Hyp), which is a value-added amino acid and has been widely used in the fields of medicine, food, and cosmetics. In this study, a multivariate modular metabolic engineering approach was used to remove the bottleneck in the synthesis pathway of t4Hyp. Results Escherichia coli t4Hyp synthesis was performed using two modules: a α-ketoglutarate (α-KG) synthesis module (K module) and L-proline synthesis with hydroxylation module (H module). First, α-KG attrition was reduced, and then, L-proline consumption was inhibited. Subsequently, to improve the contribution to proline synthesis with hydroxylation, optimization of gene overexpression, promotor, copy number, and the fusion system was performed. Finally, optimization of the H and K modules was performed in combination to balance metabolic flow. Using the final module H1K4 in a shaking flask culture, 8.80 g/L t4Hyp was produced, which was threefold higher than that produced by the W0 strain. Conclusions These strategies demonstrate that a microbial cell factory can be systematically optimized by modular engineering for efficient production of t4Hyp. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01884-4.
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Observation of WWW Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2022; 129:061803. [PMID: 36018638 DOI: 10.1103/physrevlett.129.061803] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 06/23/2022] [Indexed: 06/15/2023]
Abstract
This Letter reports the observation of WWW production and a measurement of its cross section using 139 fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from WWW production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive WWW production cross section is measured to be 820±100 (stat)±80 (syst) fb, approximately 2.6 standard deviations from the predicted cross section of 511±18 fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy.
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A detailed map of Higgs boson interactions by the ATLAS experiment ten years after the discovery. Nature 2022; 607:52-59. [PMID: 35788192 PMCID: PMC9259483 DOI: 10.1038/s41586-022-04893-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022]
Abstract
The standard model of particle physics1-4 describes the known fundamental particles and forces that make up our Universe, with the exception of gravity. One of the central features of the standard model is a field that permeates all of space and interacts with fundamental particles5-9. The quantum excitation of this field, known as the Higgs field, manifests itself as the Higgs boson, the only fundamental particle with no spin. In 2012, a particle with properties consistent with the Higgs boson of the standard model was observed by the ATLAS and CMS experiments at the Large Hadron Collider at CERN10,11. Since then, more than 30 times as many Higgs bosons have been recorded by the ATLAS experiment, enabling much more precise measurements and new tests of the theory. Here, on the basis of this larger dataset, we combine an unprecedented number of production and decay processes of the Higgs boson to scrutinize its interactions with elementary particles. Interactions with gluons, photons, and W and Z bosons-the carriers of the strong, electromagnetic and weak forces-are studied in detail. Interactions with three third-generation matter particles (bottom (b) and top (t) quarks, and tau leptons (τ)) are well measured and indications of interactions with a second-generation particle (muons, μ) are emerging. These tests reveal that the Higgs boson discovered ten years ago is remarkably consistent with the predictions of the theory and provide stringent constraints on many models of new phenomena beyond the standard model.
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