Yeast Mannans inhibit binding and phagocytosis of zymosan by mouse peritoneal macrophages

We have examined the effects of various mannans, glycoproteins, oligosaccharides, monosaccharides, and sugar phosphates on the binding and phagocytosis of yeast cell walls (zymosan) by mouse peritoneal macrophages. A phosphonomannan (PO(4):mannose ratio = 1:8:6) from kloeckera brevis was the most potent inhibitor tested; it inhibited binding and phagocytosis by 50 percent at concentrations of approximately 3-5 μg/ml and 10 μg/ml, respectively. Removal of the phosphate from this mannan by mild acid and alkaline phosphatase treatment did not appreciably reduce its capacity to inhibit zymosan phagocytosis. The mannan from saccharomyces cerevisiae mutant LB301 inhibits phagocytosis by 50 percent at 0.3 mg/ml, and a neutral exocellular glucomannan from pichia pinus inhibited phagocytosis by 50 percent at 1 mg/ml. Cell wall mannans from wild type S. cervisiae X2180, its mnn2 mutant which contains mannan with predominantly 1(arrow)6- linked mannose residues, yeast exocellular mannans and O-phosphonomannans were less efficient inhibitors requiring concentrations of 1-5 mg/ml to achieve 50 percent reduction in phagocytosis. Horseradish peroxidase, which contains high-mannose type oligosaccharides, was also inhibitory. Mannan is a specific inhibitor of zymosan binding and phagocytosis. The binding and ingestion of zymosan but not of IgG- or complement-coated erythrocytes can be obliterated by plating macrophages on substrates coated with poly-L-lysin (PLL)-mannan. Zymosan uptake was completely abolished by trypsin treatment of the macrophages and reduced by 50-60 percent in the presence of 10 mM EGTA. Pretreatment of the macrophages with chloroquine inhibited zymosan binding and ingestion. These results support the proposal that the macrophage mannose/N-acetylglucosamine receptor (P. Stahl, J.S. Rodman, M.J. Miller, and P.H. Schlesinger, 1978, Proc. Natl. Acad. Sci. U.S.A. 75:1399-1403, mediates the phagocytosis of zymosan particles

A Model of Methotrexate Encephalopathy: Neurotransmitter and Pathologic Abnormalities

Methotrexate may cause seizures, dementia, and leukoencephalopathy when given in toxic doses to children with leukemia or solid tumors. Even in therapeutic doses, treatment with this drug is associated with an increased incidence of seizures in children with leukemia. To study mechanisms of injury, juvenile rats were given multiple intraventricular injections of methotrexate and the brains were analyzed for histopathology and biogenic amine metabolites of dopamine and serotonin. Disruption of monoamine metabolism has been proposed as a cause of brain dysfunction from this chemotherapy. Multiple injections (1 or 2 mg/kg) produced convulsions in an increasingly larger percentage of animals at higher cumulative doses, and five doses produced the neuropathological changes seen in human leukoencephalopathy. A single dose reduced the concentration of brain metabolites of dopamine, but not serotonin, six hours later. The effect was less pronounced after five doses. This rodent model should be useful for studying the metabolic basis of methotrexate encephalopathy. (J Child Neurol 1986;1:351-357)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67332/2/10.1177_088307388600100406.pd

Etoricoxib in the treatment of osteoarthritis over 52-weeks: a double-blind, active-comparator controlled trial [NCT00242489]

BACKGROUND: The aim of this study was to evaluate the long-term efficacy and tolerability of etoricoxib, a COX-2 selective inhibitor, in osteoarthritis (OA) patients. METHODS: A double-blind, randomized, multicenter study was conducted in 617 patients with OA of the knee. The base study was 14 weeks in duration and consisted of 2 parts; in Part I (6 weeks), patients were allocated to once daily oral etoricoxib 5, 10, 30, 60, 90 mg or placebo. In Part II (8 weeks); the placebo, etoricoxib 5 and 10 mg groups were reallocated to etoricoxib 30, 60, or 90 mg qd or diclofenac 50 mg t.i.d. Treatment was continued for consecutive 12 and 26 week extensions. Primary efficacy endpoints were the WOMAC VA 3.0 pain subscale and investigator global assessment of disease status. Safety and tolerability were assessed by collecting adverse events throughout the study. RESULTS: Compared with placebo, the etoricoxib groups displayed significant (p < 0.05), dose-dependent efficacy for all primary endpoints in Part I; efficacy was maintained throughout the 52 weeks of the study. During the 46-week active-comparator controlled period, the etoricoxib groups demonstrated clinical efficacy that was similar to that of diclofenac 150 mg and was generally well tolerated, with a lower incidence of gastrointestinal (GI) nuisance symptoms compared with diclofenac (13.1, 14.7, and 13.5% for etoricoxib 30, 60, and 90 mg, respectively compared with 22.5% for diclofenac). CONCLUSION: In this extension study, etoricoxib, at doses ranging from 30 to 90 mg, demonstrated a maintenance of significant clinical efficacy in patients with OA through 52 weeks of treatment. Etoricoxib displayed clinical efficacy similar to diclofenac 150 mg and was generally well tolerated

The effect of changes in perilymphatic K+ on the vestibular evoked potential in the guinea pig

To investigate the effect on the functioning of the vestibular system of a rupture of Reissner’s membrane, artificial endolymph was injected in scala media of ten guinea pigs and vestibular evoked potentials (VsEPs), evoked by vertical acceleration pulses, were measured. Directly after injection of a sufficient volume to cause rupture, all ears showed a complete disappearance of VsEP, followed by partial recovery. To investigate the effect of perilymphatic potassium concentration on the vestibular sensory and neural structures, different concentrations of KCl were injected directly into the vestibule. The KCl injections resulted in a dose-dependent decrease of VsEP, followed by a dose-dependent slow recovery. This animal model clearly shows a disturbing effect of a higher than normal K+ concentration in perilymph on the vestibular and neural structures in the inner ear. Potassium intoxication is the most probable explanation for the observed effects. It is one of the explanations for Menière attacks

TOIB Study. Are topical or oral ibuprofen equally effective for the treatment of chronic knee pain presenting in primary care: a randomised controlled trial with patient preference study. [ISRCTN79353052]

BACKGROUND: Many older people have chronic knee pain. Both topical and oral non- steroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat this. Oral NSAIDS are effective, at least in the short term, but can have severe adverse effects. Topical NSAIDs also appear to be effective, at least in the short term. One might expect topical NSAIDs both to be less effective and to have fewer adverse effects than oral NSAIDs. If topical NSAIDs have fewer adverse effects this may outweigh both the reduction in effectiveness and the higher cost of topical compared to oral treatment. Patient preferences may influence the comparative effectiveness of drugs delivered via different routes. METHODS: TOIB is a randomised trial comparing topical and oral ibuprofen, with a parallel patient preference study. We are recruiting people aged 50 or over with chronic knee pain, from 27 MRC General Practice Research Framework practices across the UK. We are seeking to recruit 283 participants to the RCT and 379 to the PPS. Participants will be followed up for up to two years (with the majority reaching one year). Outcomes will be assessed by postal questionnaire, nurse examination, laboratory tests and medical record searches at one and two years or the end of the study. DISCUSSION: This study will provide new evidence on the overall costs and benefits of treating chronic knee pain with either oral or topical ibuprofen. The use of a patient preference design is unusual, but will allow us to explore how preference influences response to a medication. In addition, it will provide more information on adverse events. This study will provide evidence to inform primary care practitioners, and possibly influence practice

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT

Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal