498 research outputs found

    Brucella abortus invasion of osteocytes modulates connexin 43 and integrin expression and induces osteoclastogenesis via receptor activator of NF-ÎșB ligand and tumor necrosis factor alpha secretion

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    Osteoarticular brucellosis is the most common localization of human active disease. Osteocytes are the most abundant cells of bone. They secrete factors that regulate the differentiation of both osteoblasts and osteoclasts during bone remodeling. The aim of this study is to determine if Brucella abortus infection modifies osteocyte function. Our results indicate that B. abortus infection induced matrix metalloproteinase 2 (MMP-2), receptor activator for NF-ÎșB ligand (RANKL), proinflammatory cytokines, and keratinocyte chemoattractant (KC) secretion by osteocytes. In addition, supernatants from B. abortus-infected osteocytes induced bone marrow-derived monocytes (BMM) to undergo osteoclastogenesis. Using neutralizing antibodies against tumor necrosis factor alpha (TNF-α) or osteoprotegerin (OPG), RANKL's decoy receptor, we determined that TNF-α and RANKL are involved in osteoclastogenesis induced by supernatants from B. abortus-infected osteocytes. Connexin 43 (Cx43) and the integrins E11/gp38, integrin-α, integrin-ÎČ, and CD44 are involved in cell-cell interactions necessary for osteocyte survival. B. abortus infection inhibited the expression of Cx43 but did not modify the expression of integrins. Yet the expression of both Cx43 and integrins was inhibited by supernatants from B. abortus-infected macrophages. B. abortus infection was not capable of inducing osteocyte apoptosis. However, supernatants from B. abortus-infected macrophages induced osteocyte apoptosis in a dose-dependent manner. Taken together, our results indicate that B. abortus infection could alter osteocyte function, contributing to bone damage.Fil: Pesce Viglietti, AyelĂ©n Ivana. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de ClĂ­nicas General San MartĂ­n; ArgentinaFil: Arriola Benitez, Paula Constanza. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de ClĂ­nicas General San MartĂ­n; ArgentinaFil: Gentilini, Maria Virginia. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de ClĂ­nicas General San MartĂ­n; ArgentinaFil: Velasquez, Lis Noelia. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Fossati, Carlos Alberto. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Instituto de Estudios InmunolĂłgicos y FisiopatolĂłgicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios InmunolĂłgicos y FisiopatolĂłgicos; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias BiolĂłgicas; ArgentinaFil: Giambartolomei, Guillermo Hernan. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de ClĂ­nicas General San MartĂ­n; ArgentinaFil: Delpino, MarĂ­a Victoria. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de InmunologĂ­a, GenĂ©tica y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de ClĂ­nicas General San MartĂ­n; Argentin

    Three-dimensional elastic constitutive relations of aligned carbon nanotube architectures

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    Tailorable anisotropic intrinsic and scale-dependent properties of carbon nanotubes (CNTs) make them attractive elements in next-generation advanced materials. However, in order to model and predict the behavior of CNTs in macroscopic architectures, mechanical constitutive relations must be evaluated. This study presents the full stiffness tensor for aligned CNT-reinforced polymers as a function of the CNT packing (up to ∌20 vol. %), revealing noticeable anisotropy. Finite element models reveal that the usually neglected CNT waviness dictates the degree of anisotropy and packing dependence of the mechanical behavior, rather than any of the usually cited aggregation or polymer interphase mechanisms. Combined with extensive morphology characterization, this work enables the evaluation of structure-property relations for such materials, enabling design of aligned CNT material architectures.NECST ConsortiumUnited States. Army Research Office (Contract No. W911NF- 07-D-0004)United States. Army Research Office (Contract No. W911NF-13-D-0001)United States. National Aeronautics and Space Administration (NASA Space Technology Research Fellowship Grant No. NNX11AN79H)National Science Foundation (U.S.) (Grant No. CMMI-1130437

    Ofloxacin plus Rifampicin versus Doxycycline plus Rifampicin in the treatment of brucellosis: a randomized clinical trial [ISRCTN11871179]

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    BACKGROUND: The combination therapies recommended by the World Health Organization for treatment of brucellosis are doxycycline plus rifampicin or doxycycline plus streptomycin. Although highly successful results have been obtained with these two regimens, relapse rates as high as 14.4%. The most effective and the least toxic chemotherapy for human brucellosis is still undetermined. The aim of the present study was to investigate the efficacy, adverse effects and cost of ofloxacin plus rifampicin therapy, and doxycycline plus rifampicin therapy and evaluate in the treatment of brucellosis. METHODS: The open trial has been carried out prospectively by the two medical centers from December 1999 to December 2001 in Duzce region Turkey. The diagnosis was based on the presence of signs and symptoms compatible with brucellosis including a positive agglutination titre (≄1/160) and/or a positive culture. Doxycycline and rifampicin group consisted of 14 patients who were given doxycycline 200 mg/day plus rifampicin 600 mg/day during 45 days and this group Ofloxacin plus rifampicin group was consisted of 15 patients who were given ofloxacin 400 mg/day plus rifampicin 600 mg/day during 30 days. RESULTS: Regarding clinical and/or demographic characteristics no significant difference was found between two groups of patients that underwent two different therapeutic regimens. At the end of the therapy, two relapses were seen in both groups (p = 0.695). Although duration of therapy was two weeks shorter in group treated with rifampicin plus ofloxacin, the cure rate was similar in both groups of examinees. Fever dropped more rapidly in the group that treated with rifampicin plus ofloxacin, 74 ± 30 (ranges 48–216) vs. 106 ± 26 (ranges 48–262) hours (p = 0.016). CONCLUSIONS: Ofloxacin plus rifampicin therapy has advantages of shorter treatment duration and provided shorter course of fever with treatment than in doxycycline plus rifampicin therapy. However, cost of ofloxacin plus rifampicin treatment is higher than doxycycline plus rifampicin treatment. Because of the similar effects, adverse effects and relapses rates between two regimens, we still advice doxycycline plus rifampicin for the treatment of brucellosis for countries, which have limited resources

    Stenosis and Aneurysm of Coronary Arteries in A Patient with Behcet’s Disease

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    Coronary artery disease is extremely rare in patients with Behçet’s disease. We report the case of a patient with a history of Behçet’s disease who was admitted in our hospital with instable angina pectoris. The patient’s electrocardiogram was normal. Coronary angiography revealed aneurysm of the distal right coronary artery with a tight stenosis of the proximal part of the posterolateral branch. These two conditions were initially treated with immunosuppressive treatment. Three years later coronary angiography showed a total occlusion of the right coronary artery treated with medical therapy. More than fourteen cases of coronary involvement were reported in the literature but the etiopathogeny and the treatment are yet unknow

    Possible Brucellosis in an Early Hominin Skeleton from Sterkfontein, South Africa

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    We report on the paleopathological analysis of the partial skeleton of the late Pliocene hominin species Australopithecus africanus Stw 431 from Sterkfontein, South Africa. A previous study noted the presence of lesions on vertebral bodies diagnosed as spondylosis deformans due to trauma. Instead, we suggest that these lesions are pathological changes due to the initial phases of an infectious disease, brucellosis. The macroscopic, microscopic and radiological appearance of the lytic lesions of the lumbar vertebrae is consistent with brucellosis. The hypothesis of brucellosis (most often associated with the consumption of animal proteins) in a 2.4 to 2.8 million year old hominid has a host of important implications for human evolution. The consumption of meat has been regarded an important factor in supporting, directing or altering human evolution. Perhaps the earliest (up to 2.5 million years ago) paleontological evidence for meat eating consists of cut marks on animal remains and stone tools that could have made these marks. Now with the hypothesis of brucellosis in A. africanus, we may have evidence of occasional meat eating directly linked to a fossil hominin

    Studies of new Higgs boson interactions through nonresonant HH production in the b¯bγγ fnal state in pp collisions at √s = 13 TeV with the ATLAS detector

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    A search for nonresonant Higgs boson pair production in the b ÂŻbγγ fnal state is performed using 140 fb−1 of proton-proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. This analysis supersedes and expands upon the previous nonresonant ATLAS results in this fnal state based on the same data sample. The analysis strategy is optimised to probe anomalous values not only of the Higgs (H) boson self-coupling modifer Îșλ but also of the quartic HHV V (V = W, Z) coupling modifer Îș2V . No signifcant excess above the expected background from Standard Model processes is observed. An observed upper limit ”HH < 4.0 is set at 95% confdence level on the Higgs boson pair production cross-section normalised to its Standard Model prediction. The 95% confdence intervals for the coupling modifers are −1.4 < Îșλ < 6.9 and −0.5 < Îș2V < 2.7, assuming all other Higgs boson couplings except the one under study are fxed to the Standard Model predictions. The results are interpreted in the Standard Model efective feld theory and Higgs efective feld theory frameworks in terms of constraints on the couplings of anomalous Higgs boson (self-)interactions

    Comparison of inclusive and photon-tagged jet suppression in 5.02 TeV Pb+Pb collisions with ATLAS

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    Searches for lepton-flavour-violating decays of the Higgs boson into eτ and Ότ in \sqrt{s} = 13 TeV pp collisions with the ATLAS detector

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    Abstract This paper presents direct searches for lepton flavour violation in Higgs boson decays, H → eτ and H → Ότ, performed using data collected with the ATLAS detector at the LHC. The searches are based on a data sample of proton-proton collisions at a centre-of-mass energy s s \sqrt{s} = 13 TeV, corresponding to an integrated luminosity of 138 fb−1. Leptonic (τ → ℓΜℓΜτ) and hadronic (τ → hadrons Μτ) decays of the τ-lepton are considered. Two background estimation techniques are employed: the MC-template method, based on data-corrected simulation samples, and the Symmetry method, based on exploiting the symmetry between electrons and muons in the Standard Model backgrounds. No significant excess of events is observed and the results are interpreted as upper limits on lepton-flavour-violating branching ratios of the Higgs boson. The observed (expected) upper limits set on the branching ratios at 95% confidence level, B B \mathcal{B} (H → eτ) < 0.20% (0.12%) and B B \mathcal{B} (H → Ότ ) < 0.18% (0.09%), are obtained with the MC-template method from a simultaneous measurement of potential H → eτ and H → Ότ signals. The best-fit branching ratio difference, B B \mathcal{B} (H → Ότ) → B B \mathcal{B} (H → eτ), measured with the Symmetry method in the channel where the τ-lepton decays to leptons, is (0.25 ± 0.10)%, compatible with a value of zero within 2.5σ

    Measurement of the H → γ γ and H → ZZ∗ → 4 cross-sections in pp collisions at √s = 13.6 TeV with the ATLAS detector

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    The inclusive Higgs boson production cross section is measured in the di-photon and the Z Z∗ → 4 decay channels using 31.4 and 29.0 fb−1 of pp collision data respectively, collected with the ATLAS detector at a centre of-mass energy of √s = 13.6 TeV. To reduce the model dependence, the measurement in each channel is restricted to a particle-level phase space that closely matches the chan nel’s detector-level kinematic selection, and it is corrected for detector effects. These measured fiducial cross-sections are σfid,Îł Îł = 76+14 −13 fb, and σfid,4 = 2.80 ± 0.74 fb, in agreement with the corresponding Standard Model predic tions of 67.6±3.7 fb and 3.67±0.19 fb. Assuming Standard Model acceptances and branching fractions for the two chan nels, the fiducial measurements are extrapolated to the full phase space yielding total cross-sections of σ (pp → H) = 67+12 −11 pb and 46±12 pb at 13.6 TeV from the di-photon and Z Z∗ → 4 measurements respectively. The two measure ments are combined into a total cross-section measurement of σ (pp → H) = 58.2±8.7 pb, to be compared with the Stan dard Model prediction of σ (pp → H)SM = 59.9 ± 2.6 p

    Model-independent search for the presence of new physics in events including H → γγ with s \sqrt{s} = 13 TeV pp data recorded by the ATLAS detector at the LHC

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    Abstract A model-independent search for new physics leading to final states containing a Higgs boson, with a mass of 125.09 GeV, decaying to a pair of photons is performed with 139 fb−1 of s s \sqrt{s} = 13 TeV pp collision data recorded by the ATLAS detector at the Large Hadron Collider at CERN. This search examines 22 final states categorized by the objects that are produced in association with the Higgs boson. These objects include isolated electrons or muons, hadronically decaying τ-leptons, additional photons, missing transverse momentum, and hadronic jets, as well as jets that are tagged as containing a b-hadron. No significant excesses above Standard Model expectations are observed and limits on the production cross section at 95% confidence level are set. Detector efficiencies are reported for all 22 signal regions, which can be used to convert detector-level cross-section limits reported in this paper to particle-level cross-section constraints
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