885 research outputs found

    Expression of CCN family of genes in human skin in vivo and alterations by solar-simulated ultraviolet irradiation

    Get PDF
    The CCN family of proteins is involved in diverse biological functions such as cell growth, adhesion, migration, angiogenesis, and regulation of extracellular matrix. We have investigated expression of CCN family genes and alternations induced by solar-simulated ultraviolet irradiation in human skin in vivo. Transcripts of all six CCN genes were expressed in human skin in vivo. CCN5 was most abundantly expressed followed by CCN2>CCN3>CCN1>CCN4>CCN6. Solar-simulated ultraviolet irradiation increased mRNA expression of CCN1 and CCN2. In contrast, mRNA levels of CCN3, CCN4, CCN5, and CCN6, were reduced. Knowledge gained from this study provides the foundation to explore the functional roles of CCN gene products in cutaneous biology and responses to solar ultraviolet irradiation

    Low pH immobilizes and kills human leukocytes and prevents transmission of cell-associated HIV in a mouse model

    Get PDF
    BACKGROUND: Both cell-associated and cell-free HIV virions are present in semen and cervical secretions of HIV-infected individuals. Thus, topical microbicides may need to inactivate both cell-associated and cell-free HIV to prevent sexual transmission of HIV/AIDS. To determine if the mild acidity of the healthy vagina and acid buffering microbicides would prevent transmission by HIV-infected leukocytes, we measured the effect of pH on leukocyte motility, viability and intracellular pH and tested the ability of an acidic buffering microbicide (BufferGel(Âź)) to prevent the transmission of cell-associated HIV in a HuPBL-SCID mouse model. METHODS: Human lymphocyte, monocyte, and macrophage motilities were measured as a function of time and pH using various acidifying agents. Lymphocyte and macrophage motilities were measured using video microscopy. Monocyte motility was measured using video microscopy and chemotactic chambers. Peripheral blood mononuclear cell (PBMC) viability and intracellular pH were determined as a function of time and pH using fluorescent dyes. HuPBL-SCID mice were pretreated with BufferGel, saline, or a control gel and challenged with HIV-1-infected human PBMCs. RESULTS: Progressive motility was completely abolished in all cell types between pH 5.5 and 6.0. Concomitantly, at and below pH 5.5, the intracellular pH of PBMCs dropped precipitously to match the extracellular medium and did not recover. After acidification with hydrochloric acid to pH 4.5 for 60 min, although completely immotile, 58% of PBMCs excluded ethidium homodimer-1 (dead-cell dye). In contrast, when acidified to this pH with BufferGel, a microbicide designed to maintain vaginal acidity in the presence of semen, only 4% excluded dye at 10 min and none excluded dye after 30 min. BufferGel significantly reduced transmission of HIV-1 in HuPBL-SCID mice (1 of 12 infected) compared to saline (12 of 12 infected) and a control gel (5 of 7 infected). CONCLUSION: These results suggest that physiologic or microbicide-induced acid immobilization and killing of infected white blood cells may be effective in preventing sexual transmission of cell-associated HIV

    Localization and potential role of matrix metalloproteinase-1 and tissue inhibitors of metalloproteinase-1 and -2 in different phases of bronchopulmonary dysplasia

    Get PDF
    Bronchopulmonary dysplasia (BPD) can evolve in prematurely born infants who require mechanical ventilation because of hyaline membrane disease (HMD). The development of BPD can be divided in an acute, a regenerative, a transitional, and a chronic phase. During these different phases, extensive remodeling of the lung parenchyma with re-epithelialization of the alveoli and formation of fibrosis occurs. Matrix metalloproteinase-1 (MMP-1) is an enzyme that is involved in re-epithelialization processes, and dysregulation of MMP-1 activity contributes to fibrosis. Localization of MMP-1 and its inhibitors, tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2, were investigated in lung tissue obtained from infants who died during different phases of BPD development. In all studied cases (n = 50) type-II pneumocytes were found to be immunoreactive for MMP-1, TIMP-1, and TIMP-2. During the acute and regenerative phase of BPD, type-II pneumocytes re-epithelialize the injured alveoli. This may suggest that MMP-1 and its inhibitors, expressed by type-II pneumocytes, play a role in the re-epithelialization process after acute lung injury. Although MMP-1 staining intensity remained constant in type-II pneumocytes during BPD development, TIMP-1 increased during the chronic fibrotic phase. This relative elevation of TIMP-1 compared with MMP-1 is indicative for reduced collagenolytic activity by type-II pneumocytes in chronic BPD and may contribute to fibrosis. Fibrotic foci in chronic BPD contained fibroblasts immunoreactive for MMP-1 and TIMP-1 and -2. This may indicate that decreased collagen turnover by fibroblasts contributes to fibrosis in BPD development

    Measurement of B(t->Wb)/B(t->Wq) at the Collider Detector at Fermilab

    Get PDF
    We present a measurement of the ratio of top-quark branching fractions R= B(t -> Wb)/B(t -> Wq), where q can be a b, s or a d quark, using lepton-plus-jets and dilepton data sets with integrated luminosity of ~162 pb^{-1} collected with the Collider Detector at Fermilab during Run II of the Tevatron. The measurement is derived from the relative numbers of t-tbar events with different multiplicity of identified secondary vertices. We set a lower limit of R > 0.61 at 95% confidence level.Comment: 7 pages, 2 figures, published in Physical Review Letters; changes made to be consistent with published versio

    Acid Solution Is a Suitable Medium for Introducing QX-314 into Nociceptors through TRPV1 Channels to Produce Sensory-Specific Analgesic Effects

    Get PDF
    BACKGROUND: Previous studies have demonstrated that QX-314, an intracellular sodium channel blocker, can enter into nociceptors through capsaicin-activated TRPV1 or permeation of the membrane by chemical enhancers to produce a sensory-selective blockade. However, the obvious side effects of these combinations limit the application of QX-314. A new strategy for targeting delivery of QX-314 into nociceptors needs further investigation. The aim of this study is to test whether acidic QX-314, when dissolves in acidic solution directly, can enter into nociceptors through acid-activated TRPV1 and block sodium channels from the intracellular side to produce a sensory-specific analgesic effect. METHODOLOGY/PRINCIPAL FINDINGS: Acidic solution or noradrenaline was injected intraplantarly to induce acute pain behavior in mice. A chronic constrictive injury model was performed to induce chronic neuropathic pain. A sciatic nerve blockade model was used to evaluate the sensory-specific analgesic effects of acidic QX-314. Thermal and mechanical hyperalgesia were measured by using radiant heat and electronic von Frey filaments test. Spinal Fos protein expression was determined by immunohistochemistry. The expression of p-ERK was detected by western blot assay. Whole cell clamp recording was performed to measure action potentials and total sodium current in rats DRG neurons. We found that pH 5.0 PBS solution induced behavioral hyperalgesia accompanied with the increased expression of spinal Fos protein and p-ERK. Pretreatment with pH 5.0 QX-314, and not pH 7.4 QX-314, alleviated pain behavior, inhibited the increased spinal Fos protein and p-ERK expression induced by pH 5.0 PBS or norepinephrine, blocked sodium currents and abolished the production of action potentials evoked by current injection. The above effects were prevented by TRPV1 channel inhibitor SB366791, but not by ASIC channel inhibitor amiloride. Furthermore, acidic QX-314 employed adjacent to the sciatic nerve selectively blocked the sensory but not the motor functions in naĂŻve and CCI mice. CONCLUSIONS/SIGNIFICANCE: Acid solution is a suitable medium for introducing QX-314 into nociceptors through TRPV1 channels to produce a sensory-specific analgesic effect

    Search for ZZ and ZW Production in ppbar Collisions at sqrt(s) = 1.96 TeV

    Get PDF
    We present a search for ZZ and ZW vector boson pair production in ppbar collisions at sqrt(s) = 1.96 TeV using the leptonic decay channels ZZ --> ll nu nu, ZZ --> l l l' l' and ZW --> l l l' nu. In a data sample corresponding to an integrated luminosity of 194 pb-1 collected with the Collider Detector at Fermilab, 3 candidate events are found with an expected background of 1.0 +/- 0.2 events. We set a 95% confidence level upper limit of 15.2 pb on the cross section for ZZ plus ZW production, compared to the standard model prediction of 5.0 +/- 0.4 pb.Comment: 7 pages, 2 figures. This version is accepted for publication by Phys. Rev. D Rapid Communication

    Measurement of the Cross Section for Prompt Diphoton Production in p-pbar Collisions at sqrt(s) = 1.96 TeV

    Get PDF
    We report a measurement of the rate of prompt diphoton production in ppˉp\bar{p} collisions at s=1.96 TeV\sqrt{s}=1.96 ~\hbox{TeV} using a data sample of 207 pb−1^{-1} collected with the upgraded Collider Detector at Fermilab (CDF II). The background from non-prompt sources is determined using a statistical method based on differences in the electromagnetic showers. The cross section is measured as a function of the diphoton mass, the transverse momentum of the diphoton system, and the azimuthal angle between the two photons and is found to be consistent with perturbative QCD predictions.Comment: 7 pages, 3 figures,revtex4. Version accepted by PRL, but with cross section tables i

    Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

    Get PDF
    We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

    Search for the standard model Higgs boson at LEP

    Get PDF

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

    Get PDF
    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  Όb-1 of data as a function of transverse momentum (pT) and the transverse energy (ÎŁETPb) 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 ÎŁETPb. 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 ÎŁETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ÎŁETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁥2Δϕ modulation for all ÎŁETPb ranges and particle pT
    • 

    corecore