624 research outputs found

    HelixFold-Single: MSA-free Protein Structure Prediction by Using Protein Language Model as an Alternative

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    AI-based protein structure prediction pipelines, such as AlphaFold2, have achieved near-experimental accuracy. These advanced pipelines mainly rely on Multiple Sequence Alignments (MSAs) as inputs to learn the co-evolution information from the homologous sequences. Nonetheless, searching MSAs from protein databases is time-consuming, usually taking dozens of minutes. Consequently, we attempt to explore the limits of fast protein structure prediction by using only primary sequences of proteins. HelixFold-Single is proposed to combine a large-scale protein language model with the superior geometric learning capability of AlphaFold2. Our proposed method, HelixFold-Single, first pre-trains a large-scale protein language model (PLM) with thousands of millions of primary sequences utilizing the self-supervised learning paradigm, which will be used as an alternative to MSAs for learning the co-evolution information. Then, by combining the pre-trained PLM and the essential components of AlphaFold2, we obtain an end-to-end differentiable model to predict the 3D coordinates of atoms from only the primary sequence. HelixFold-Single is validated in datasets CASP14 and CAMEO, achieving competitive accuracy with the MSA-based methods on the targets with large homologous families. Furthermore, HelixFold-Single consumes much less time than the mainstream pipelines for protein structure prediction, demonstrating its potential in tasks requiring many predictions. The code of HelixFold-Single is available at https://github.com/PaddlePaddle/PaddleHelix/tree/dev/apps/protein_folding/helixfold-single, and we also provide stable web services on https://paddlehelix.baidu.com/app/drug/protein-single/forecast

    Cost analysis of improving emergency care for aged care residents under a Hospital in the Nursing Home program in Australia

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    Background This study aims to examine the costs associated with a Hospital in the Nursing Home (HiNH) program in Queensland Australia directed at patients from residential aged care facilities (RACFs) with emergency care needs. Methods A cost analysis was undertaken comparing the costs under the HiNH program and the current practice, in parallel with a pre-post controlled study design. The study was conducted in two Queensland public hospitals: the Royal Brisbane and Women’s Hospital (intervention hospital) and the Logan Hospital (control hospital). Main outcome measures were the associated incremental costs or savings concerning the HiNH program provision and the acute hospital care utilisation over one year after intervention. Results The initial deterministic analysis calculated the total induced mean costs associated with providing the HiNH program over one year as AU488,116,andthetotalinducedsavingsrelatingtoacutehospitalcareserviceutilisationofAU488,116, and the total induced savings relating to acute hospital care service utilisation of AU8,659,788. The total net costs to the health service providers were thus calculated at -AU8,171,671perannum.Resultsfromtheprobabilisticsensitivityanalysis(basedon10,000simulations)showedthemeanandmedianannualnetcostsassociatedwiththeHiNHprogramimplementationwere−AU8,171,671 per annum. Results from the probabilistic sensitivity analysis (based on 10,000 simulations) showed the mean and median annual net costs associated with the HiNH program implementation were -AU8,444,512 and–AU8,202,676,andastandarddeviationof2,955,346.Therewas958,202,676, and a standard deviation of 2,955,346. There was 95% certainty that the values of net costs would fall within the range from -AU15,018,055 to -AU$3,358,820. Conclusions The costs relating to implementing the HiNH program appear to be much less than the savings in terms of associated decreases in acute hospital service utilisation. The HiNH service model is likely to have the cost-saving potential while improving the emergency care provision for RACF residents

    ULK1 phosphorylates Exo70 to suppress breast cancer metastasis

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    äčłè…șç™Œæ˜Żćšèƒć„łæ€§ç”Ÿć‘œć„ćș·çš„â€œć€Žć·æ€æ‰‹â€ïŒŒè€Œèżœć€„èœŹç§»æ˜Żäčłè…șç™Œæ‚Łè€…æ­»äșĄçš„äž»èŠćŽŸć› ă€‚ć› æ­€ïŒŒäș†è§Łäčłè…șç™ŒćŠ‚äœ•ć‘ćŠšäŸ”èą­ć’ŒèœŹç§»ïŒŒćŻčäșŽæœ‰æ•ˆæȻ疗äčłè…șç™Œă€ć»¶é•żç—…äșșç”Ÿć­˜æœŸć…·æœ‰é‡èŠæ„äč‰ă€‚æœŹç ”ç©¶äž­ïŒŒèŻ„曱队揑现ULK1é€šèż‡ç»“ćˆćč¶çŁ·é…žćŒ–èƒžæłŒè›‹ç™œć€ćˆäœ“ć…łé”źäșšćŸșExo70æ„æŠ‘ćˆ¶äčłè…șç™ŒèœŹç§»ă€‚ULK1ćŻčExo70侊Ser47Ser59撌Ser89䜍ç‚čçš„çŁ·é…žćŒ–ïŒŒäž„é‡ćœ°ć‰ŠćŒ±äș†Exo70的è‡Șèș«ćŻĄèšćŒ–ć’ŒäžŽć…¶ćźƒèƒžć€–ćˆ†æłŒć€ćˆäœ“äșšćŸșçš„ç»“ćˆïŒŒèż›è€Œć‡ć°‘äș†ç»†èƒžèżćŠšäŒȘè¶łćœąæˆä»„ćŠćŸșèŽšé‡‘ć±žè›‹ç™œé…¶çš„ćˆ†æłŒïŒŒä»Žè€ŒæŠ‘ćˆ¶äčłè…șç™Œç»†èƒžçš„èżç§»ć’ŒäŸ”èą­ă€‚èŻ„èźșæ–‡éŠ–æŹĄæ­ç€șäș†èƒžć€–ćˆ†æłŒć€ćˆäœ“é‡èŠæˆć‘˜Exo70朹äčłè…ș癌侭揗戰ULK1撌ERK1/2çš„ćŒé‡çŁ·é…žćŒ–è°ƒæŽ§ïŒŒä»Žè€ŒäœżćŸ—äčłè…șç™Œç»†èƒžćŻä»„æ čæźć€–çŽŻćąƒæ„ć†łćźšæœœäŒèż˜æ˜Żć‘ćŠšäŸ”èą­èœŹç§»ïŒŒäžșäčłè…ș癌的æČ»ç–—æäŸ›äș†æ–°çš„理èźșćŸș础。 æœŹèźșæ–‡çš„é€šèźŻäœœè€…äžșć è‰łè‰łć‰Żæ•™æŽˆă€éƒ­ć·æ•™æŽˆć’ŒèƒĄć€©æƒ æ•™æŽˆă€‚ćŒ»ć­Šé™ąćšćŁ«ç”ŸæŻ›äžœćȘ›ă€ć è‰łè‰łć‰Żæ•™æŽˆă€ćŽæ–ŒćšćŁ«ć’ŒćŒ»ć­Šé™ąćšćŁ«ç”ŸäșŽćŒșäžșć…±ćŒçŹŹäž€äœœè€…ă€‚ă€Abstract】Increased expression of protein kinase ULK1 was reported to negatively correlate with breast cancer metastasis. Here we report that ULK1 suppresses the migration and invasion of human breast cancer cells. The suppressive effect is mediated through direct phosphorylation of Exo70, a key component of the exocyst complex. ULK1 phosphorylation inhibits Exo70 homo-oligomerization as well as its assembly to the exocyst complex, which are needed for cell protrusion formation and matrix metalloproteinases secretion during cell invasion. Reversely, upon growth factor stimulation, Exo70 is phosphorylated by ERK1/2, which in turn suppresses its phosphorylation by ULK1. Together, our study identifies Exo70 as a substrate of ULK1 that inhibits cancer metastasis, and demonstrates that two counteractive regulatory mechanisms are well orchestrated during tumor cell invasion.This work was supported by the grants from the National Natural Science Foundation of China (81572589, U1405228, 81472568, and 31770860), the Natural Science Foundation of Fujian grant (2017J06020, 2018J01400, 2017R1036-4, 2017R1036-6, 2016R1034-1, and 2016R1034-4), and the Xiamen Science and Technology grant (3502Z20159013) to Y.-y.Z. and T.H., and National Institute of Health R01 GM111128 to W.G.èŻ„èźșæ–‡çš„ç ”ç©¶æˆæžœæ˜Żćœšć›œćź¶è‡Ș然科歊ćŸș金撌穏ć»ș省ćŸșé‡‘çš„è”„ćŠ©äž‹ïŒŒäžŽçŸŽć›œćźŸć€•æł•ć°Œäșšć€§ć­Šć’Œæž…ćŽć€§ć­Šć…±ćŒćäœœćźŒæˆçš„

    Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

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    A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

    Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

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    A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV

    Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

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    Measurement of the W gamma Production Cross Section in Proton-Proton Collisions at root s=13 TeV and Constraints on Effective Field Theory Coefficients

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    A fiducial cross section for W gamma production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137 fb(-1) of data collected using the CMS detector at the LHC. The W -> e nu and mu nu decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum chromodynamics. In addition, 95% confidence level intervals are reported for anomalous triple-gauge couplings within the framework of effective field theory.Peer reviewe

    Search for top squark production in fully hadronic final states in proton-proton collisions at root s=13 TeV

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    A search for production of the supersymmetric partners of the top quark, top squarks, is presented. The search is based on proton-proton collision events containing multiple jets, no leptons, and large transverse momentum imbalance. The data were collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV, and correspond to an integrated luminosity of 137 fb(-1). The targeted signal production scenarios are direct and gluino-mediated top squark production, including scenarios in which the top squark and neutralino masses are nearly degenerate. The search utilizes novel algorithms based on deep neural networks that identify hadronically decaying top quarks and W bosons, which are expected in many of the targeted signal models. No statistically significant excess of events is observed relative to the expectation from the standard model, and limits on the top squark production cross section are obtained in the context of simplified supersymmetric models for various production and decay modes. Exclusion limits as high as 1310 GeVare established at the 95% confidence level on the mass of the top squark for direct top squark production models, and as high as 2260 GeV on the mass of the gluino for gluino-mediated top squark production models. These results represent a significant improvement over the results of previous searches for supersymmetry by CMS in the same final state.Peer reviewe

    Observation of tW production in the single-lepton channel in pp collisions at root s=13 TeV

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    A measurement of the cross section of the associated production of a single top quark and a W boson in final states with a muon or electron and jets in proton-proton collisions at root s = 13 TeV is presented. The data correspond to an integrated luminosity of 36 fb(-1) collected with the CMS detector at the CERN LHC in 2016. A boosted decision tree is used to separate the tW signal from the dominant t (t) over bar background, whilst the subleading W+jets and multijet backgrounds are constrained using data-based estimates. This result is the first observation of the tW process in final states containing a muon or electron and jets, with a significance exceeding 5 standard deviations. The cross section is determined to be 89 +/- 4 (stat) +/- 12 (syst) pb, consistent with the standard model.Peer reviewe

    Measurements of Higgs boson production cross sections and couplings in the diphoton decay channel at root s=13 TeV

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    Measurements of Higgs boson production cross sections and couplings in events where the Higgs boson decays into a pair of photons are reported. Events are selected from a sample of proton-proton collisions at root s = 13TeV collected by the CMS detector at the LHC from 2016 to 2018, corresponding to an integrated luminosity of 137 fb(-1). Analysis categories enriched in Higgs boson events produced via gluon fusion, vector boson fusion, vector boson associated production, and production associated with top quarks are constructed. The total Higgs boson signal strength, relative to the standard model (SM) prediction, is measured to be 1.12 +/- 0.09. Other properties of the Higgs boson are measured, including SM signal strength modifiers, production cross sections, and its couplings to other particles. These include the most precise measurements of gluon fusion and vector boson fusion Higgs boson production in several different kinematic regions, the first measurement of Higgs boson production in association with a top quark pair in five regions of the Higgs boson transverse momentum, and an upper limit on the rate of Higgs boson production in association with a single top quark. All results are found to be in agreement with the SM expectations.Peer reviewe
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