1,378 research outputs found

    Pressure responsive nanogel base on Alginate‐Cyclodextrin with enhanced apoptosis mechanism for colon cancer delivery

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    5‐Fluorouracil (5‐Fu) commonly use in the treatment of different kinds of cancer, but limited cellular uptake and death is still a problem. Herein, we report a simple process for the synthesis of pressure‐sensitive nanogels that indicate to be appropriate in the delivery of 5‐Fu. The hydrogels (Al‐CD) prepare by crosslinking of alginate (Al) with modified beta Cyclodextrin (ÎČ‐CD) as Crosslinker. Next, nanoparticles obtaine by an emulsification method. 5‐Fu as model drug loades into the Al‐CD nanogels easily by mixing it in aqueous solution with the nanoparticles. The results revealed that the Al‐CD nanogels are cytocompatible. They have also a noticeable drug encapsulation (82.1 ±5.7%) while they can release (in vitro controlled) 5‐Fu in conditions that imitate the intravascular pressure conditions. These nanogels can rapidly be taken up by HT‐29 cells (a colon cell line). In addition, a higher 5‐Fu intracellular accumulation and a significant cell death extension by apoptosis mechanism is notice when compare with free 5‐Fu. Accordingly, the developed nanogels can be employe as an excellent candidate to overcome the inefficiency of 5‐Fu in anticancer treatments and possibly can employe for further evaluation as a chemotherapical agent in applications beyond cancer. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 349–359, 2018.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143710/1/jbma36242.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143710/2/jbma36242_am.pd

    Biodegradable elastic nanofibrous platforms with integrated flexible heaters for on-demand drug delivery

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    Delivery of drugs with controlled temporal profiles is essential for wound treatment and regenerative medicine applications. For example, bacterial infection is a key challenge in the treatment of chronic and deep wounds. Current treatment strategies are based on systemic administration of high doses of antibiotics, which result in side effects and drug resistance. On-demand delivery of drugs with controlled temporal profile is highly desirable. Here, we have developed thermally controllable, antibiotic-releasing nanofibrous sheets. Poly(glycerol sebacate)- poly(caprolactone) (PGS-PCL) blends were electrospun to form elastic polymeric sheets with fiber diameters ranging from 350 to 1100 nm and substrates with a tensile modulus of approximately 4-8 MPa. A bioresorbable metallic heater was patterned directly on the nanofibrous substrate for applying thermal stimulation to release antibiotics on-demand. In vitro studies confirmed the platform’s biocompatibility and biodegradability. The released antibiotics were potent against tested bacterial strains. These results may pave the path toward developing electronically controllable wound dressings that can deliver drugs with desired temporal patterns

    Engineered Ovalbumin Nanoparticles for Cancer Immunotherapy

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    Ovalbumin (OVA) is a protein antigen that is widely used for eliciting cellular and humoral immune responses in cancer immunotherapy. As an alternative to solute OVA, engineering approach is developed herein towards protein nanoparticles (pNPs) based on reactive electrospraying. The resulting pNPs are comprised of polymerized OVA, where individual OVA molecules are chemically linked via poly(ethylene glycol) (PEG) units. Controlling the PEG/OVA ratio allows for fine‐tuning of critical physical properties, such as particle size, elasticity, and, at the molecular level, mesh size. As the PEG/OVA ratio decreased, OVA pNPs are more effectively processed by dendritic cells, resulting in higher OT‐I CD8+ cells proliferation in vitro. Moreover, pNPs with lower PEG/OVA ratios elicit enhanced lymphatic drainage in vivo and increased uptake by lymph node macrophages, dendritic cells, and B cells, while 500 nm OVA pNPs show poor draining lymph nodes delivery. In addition, pNPs with lower PEG/OVA ratios result in higher anti‐OVA antibody titers in vivo, suggesting improved humoral immune responses. Importantly, OVA pNPs result in significantly increased median survival relative to solute OVA antigen in a mouse model of B16F10‐OVA melanoma. This work demonstrates that precisely engineered OVA pNPs can improve the overall anti‐tumor response compared to solute antigen.As an alternative to solute antigens for cancer immunotherapy, protein nanoparticles (pNPs) comprised of polymerized antigen linked by poly(ethylene glycol) units are developed based on reactive electrospraying. This engineering approach allows fine tuning the physico‐chemical properties of pNPs such as particle size, elasticity, and mesh size. These properties are related to pNPs enhanced antigen‐specific immune responses and improved anti‐tumor efficacy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163384/3/adtp202000100-sup-0001-SuppMat.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163384/2/adtp202000100.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163384/1/adtp202000100_am.pd

    Robust Anti‐Tumor T Cell Response with Efficient Intratumoral Infiltration by Nanodisc Cancer Immunotherapy

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    Potent anti‐tumor T cell response and efficient intratumoral T cell infiltration are the major challenges for therapeutic cancer vaccines. To address these issues, a nanovaccine system is designed to promote anti‐tumor T cell responses, and intratumoral infiltration is examined in various murine tumor models. Subcutaneous vaccination with nanodiscs carrying human papillomavirus (HPV)‐16 E7 antigen elicits as high as ∌32% E7‐specific CD8α+ T cell responses in circulation, representing a 29‐fold improvement over the soluble peptide vaccination. Importantly, nanodisc vaccination also promotes robust intratumoral T cell infiltration and eliminates HPV16 E6/E7‐expressing TC‐1 tumors at mucosal sites, including lungs, inner lip, and intravaginal tissues. In a benchmark study with a live Listeria vaccine combined with anti‐PD‐1 IgG, nanodiscs plus anti‐PD‐1 immune checkpoint blockade elicits comparable levels of T cell responses with anti‐tumor efficacy. Furthermore, compared with Complete Freund’s Adjuvant combined with tetanus toxoid, nanodisc vaccination in HLA‐A02 mice generates >200‐fold stronger IFN‐γ+ T cell responses against a neoantigen from an HLA‐A02 melanoma patient. Overall, these results show that the nanodisc system is a promising cancer vaccine platform for inducing anti‐tumor T cell responses.Efficient infiltration of T cells in solid cancer is a major challenge for cancer immunotherapy. A nanoparticle vaccine system is developed to promote T cell infiltration into peripheral mucosal tissues and eliminate disseminated tumors. Nanodiscs are broadly applicable with a wide range of tumor antigens, thus providing a versatile and potent vaccine platform for eliciting T cell immunity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156420/3/adtp202000094.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156420/2/adtp202000094-sup-0001-SuppMat.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156420/1/adtp202000094_am.pd

    Search for invisible decays of the Higgs boson produced via vector boson fusion in proton-proton collisions at s\sqrt{s} = 13 TeV

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    A search for invisible decays of the Higgs boson produced via vector boson fusion (VBF) has been performed with 101  fb−1^{-1} of proton-proton collisions delivered by the LHC at s\sqrt{s} =13  TeV and collected by the CMS detector in 2017 and 2018. The sensitivity to the VBF production mechanism is enhanced by constructing two analysis categories, one based on missing transverse momentum and a second based on the properties of jets. In addition to control regions with Z and W boson candidate events, a highly populated control region, based on the production of a photon in association with jets, is used to constrain the dominant irreducible background from the invisible decay of a Z boson produced in association with jets. The results of this search are combined with all previous measurements in the VBF topology, based on data collected in 2012 (at s\sqrt{s} =8  TeV), 2015, and 2016, corresponding to integrated luminosities of 19.7, 2.3, and 36.3  fb−1^{-1}, respectively. The observed (expected) upper limit on the invisible branching fraction of the Higgs boson is found to be 0.18 (0.10) at the 95% confidence level, assuming the standard model production cross section. The results are also interpreted in the context of Higgs-portal models

    Observation of the Bc+_\mathrm{c}^+ Meson in Pb-Pb and pp Collisions at sNN\sqrt{s_{\mathrm{NN}}} = 5.02 TeV and Measurement of its Nuclear Modification Factor

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    The Bc+_\mathrm{c}^+ meson is observed for the first time in heavy ion collisions. Data from the CMS detector are used to study the production of the Bc+_\mathrm{c}^+ meson in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a center-of-mass energy per nucleon pair of sNN\sqrt{s_{\mathrm{NN}}} = 5.02 TeV , via the Bc+_\mathrm{c}^+ → (J/ψ → ÎŒ+^+Ό−^−)ÎŒ+^+ΜΌ_ÎŒ decay. The Bc+_\mathrm{c}^+ nuclear modification factor, derived from the PbPb-to-pp ratio of production cross sections, is measured in two bins of the trimuon transverse momentum and of the PbPb collision centrality. The Bc+_\mathrm{c}^+meson is shown to be less suppressed than quarkonia and most of the open heavy-flavor mesons, suggesting that effects of the hot and dense nuclear matter created in heavy ion collisions contribute to its production. This measurement sets forth a promising new probe of the interplay of suppression and enhancement mechanisms in the production of heavy-flavor mesons in the quark-gluon plasma

    Measurement of the B0^{0}s_{s} → ÎŒ+^{+} Ό−^{-} decay properties and search for the B0^{0} → ÎŒ+^{+}Ό−^{-} decay in proton-proton collisions at √s = 13 TeV

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    Search for top squarks in the four-body decay mode with single lepton final states in proton-proton collisions at s \sqrt{s} = 13 TeV

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    A search for the pair production of the lightest supersymmetric partner of the top quark, the top squark (t∌1), is presented. The search targets the four-body decay of the t∌1, which is preferred when the mass difference between the top squark and the lightest supersymmetric particle is smaller than the mass of the W boson. This decay mode consists of a bottom quark, two other fermions, and the lightest neutralino (χ∌01), which is assumed to be the lightest supersymmetric particle. The data correspond to an integrated luminosity of 138 fb−1 of proton-proton collisions at a center-of-mass energy of 13 TeV collected by the CMS experiment at the CERN LHC. Events are selected using the presence of a high-momentum jet, an electron or muon with low transverse momentum, and a significant missing transverse momentum. The signal is selected based on a multivariate approach that is optimized for the difference between m(t∌1) and m(χ∌01). The contribution from leading background processes is estimated from data. No significant excess is observed above the expectation from standard model processes. The results of this search exclude top squarks at 95% confidence level for masses up to 480 and 700 GeV for m(t∌1) − m(χ∌01) = 10 and 80 GeV, respectively

    Search for a massive scalar resonance decaying to a light scalar and a Higgs boson in the four b quarks final state with boosted topology

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    Search for Higgs Boson Decay to a Charm Quark-Antiquark Pair in Proton-Proton Collisions at √s = 13 TeV

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    A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H→cÂŻc, produced in association with a leptonically decaying V (W or Z) boson is presented. The search is performed with proton-proton collisions at √s=13  TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138  fb−1. Novel charm jet identification and analysis methods using machine learning techniques are employed. The analysis is validated by searching for Z→cÂŻc in VZ events, leading to its first observation at a hadron collider with a significance of 5.7 standard deviations. The observed (expected) upper limit on σ(VH)B(H→cÂŻc) is 0.94 (0.50+0.22−0.15)pb at 95% confidence level (C.L.), corresponding to 14 (7.6+3.4−2.3) times the standard model prediction. For the Higgs-charm Yukawa coupling modifier, Îșc, the observed (expected) 95% C.L. interval is 1.1<|Îșc|<5.5 (|Îșc|<3.4), the most stringent constraint to date
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