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Davis JC, van der Heijde DM, Braun J, Dougados M, Cush J, Clegg D, Inman RD, Kivitz A, Zhou L, Solinger A, Tsuji W. Sustained durability and tolerability of etanercept in ankylosing spondylitis for 96 weeks. Ann Rheum Dis 2005; 64:1557-62. [PMID: 15843448 PMCID: PMC1755272 DOI: 10.1136/ard.2004.035105] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
OBJECTIVE To evaluate the continued safety and durability of clinical response in patients with ankylosing spondylitis receiving etanercept. METHODS 277 patients who had participated in a previous randomised, double blind, placebo controlled 24 week trial were eligible to continue in this open label extension study. All patients who enrolled in the open label extension (n = 257) received subcutaneous etanercept 25 mg twice weekly for up to 72 weeks, for a combined 96 weeks of cumulative trial and open label experience. For the patients who had received etanercept for 24 weeks in the double blind trial, this represented almost 2 years of continuous etanercept treatment. RESULTS Patients continuing etanercept treatment had a sustained response for almost 2 years, with 74% achieving an ASsessments in Ankylosing Spondylitis 20% (ASAS 20) response after 96 weeks of etanercept treatment. Patients who had received placebo in the preceding double blind trial had similar responses, with 70% of patients attaining an ASAS 20 response after 24 weeks of etanercept treatment and 78% achieving an ASAS 20 response after 72 weeks. Improved spinal mobility was seen in both groups. Etanercept was well tolerated in patients treated for up to 96 weeks. CONCLUSION The subcutaneous administration of twice weekly doses of etanercept provided sustained durability of response in the improvement of signs and symptoms of ankylosing spondylitis for nearly 2 years.
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Gescuk B, Wu AJ, Whitcher JP, Daniels TE, Lund S, Fye K, Davis JC. Lamivudine is not effective in primary Sjögren's syndrome. Ann Rheum Dis 2005; 64:1326-30. [PMID: 15708886 PMCID: PMC1755647 DOI: 10.1136/ard.2004.031393] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Retroviral infection has been implicated in the pathogenesis of primary Sjögren's syndrome. OBJECTIVE To examine the efficacy of the reverse transcriptase inhibitor lamivudine in patients with this syndrome. METHODS 16 patients with primary Sjögren's syndrome were randomised to receive either lamivudine 150 mg twice daily or placebo for three months. Measures of lacrimal and salivary function, including minor salivary gland biopsies, were obtained before and after treatment. RESULTS Treatment with lamivudine did not result in significant improvement in the primary outcome measure of unstimulated whole salivary flow or other secondary measures, including minor salivary gland biopsy focus scores. CONCLUSION Lamivudine is not effective in patients with primary Sjögren's syndrome, suggesting either that a retroviral aetiology is not present or that it may be important only in early disease.
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Summers VK, Hipkin LJ, Osborne Hughes R, Davis JC. Panhypopituitarism after cured tuberculous meningitis. BRITISH MEDICAL JOURNAL 2004; 1:359. [PMID: 15508206 PMCID: PMC1984892 DOI: 10.1136/bmj.1.5588.359] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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154
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Davis JC, Donaldson MG, Ashe MC, Khan KM. The role of balance and agility training in fall reduction. A comprehensive review. EUROPA MEDICOPHYSICA 2004; 40:211-21. [PMID: 16172589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
AIM In the elderly, falls and fall-related injuries are a major problem worldwide and the number of injuries are continuing to increase. It is well established that stability requires a well-functioning muscular-skeletal system as well as an intact balance system. The purpose of this comprehensive review of controlled trials is to examine the evidence for the value of balance and agility training in preventing falls and injuries resulting from falls in older people. METHODS Thirteen studies meeting our inclusion criteria have been reviewed. RESULTS Of these 13 studies, 6 demonstrated a significant reduction in the rate of falls. CONCLUSIONS The conclusion is drawn that an exercise program with a balance component in healthy community dwelling older people is likely to prevent future falls.
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155
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Hanaguri T, Lupien C, Kohsaka Y, Lee DH, Azuma M, Takano M, Takagi H, Davis JC. A ‘checkerboard’ electronic crystal state in lightly hole-doped Ca2-xNaxCuO2Cl2. Nature 2004; 430:1001-5. [PMID: 15329714 DOI: 10.1038/nature02861] [Citation(s) in RCA: 587] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2004] [Accepted: 07/13/2004] [Indexed: 11/09/2022]
Abstract
The phase diagram of hole-doped copper oxides shows four different electronic phases existing at zero temperature. Familiar among these are the Mott insulator, high-transition-temperature superconductor and metallic phases. A fourth phase, of unknown identity, occurs at light doping along the zero-temperature bound of the 'pseudogap' regime. This regime is rich in peculiar electronic phenomena, prompting numerous proposals that it contains some form of hidden electronic order. Here we present low-temperature electronic structure imaging studies of a lightly hole-doped copper oxide: Ca2-xNaxCuO2Cl2. Tunnelling spectroscopy (at energies |E| > 100 meV) reveals electron extraction probabilities greatly exceeding those for injection, as anticipated for a doped Mott insulator. However, for |E| < 100 meV, the spectrum exhibits a V-shaped energy gap centred on E = 0. States within this gap undergo intense spatial modulations, with the spatial correlations of a four CuO2-unit-cell square 'checkerboard', independent of energy. Intricate atomic-scale electronic structure variations also exist within the checkerboard. These data are consistent with an unanticipated crystalline electronic state, possibly the hidden electronic order, existing in the zero-temperature pseudogap regime of Ca2-xNaxCuO2Cl2.
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Takada K, Danning CL, Kuroiwa T, Schlimgen R, Tassiulas IO, Davis JC, Yarboro CH, Fleisher TA, Boumpas DT, Illei GG. Lymphocyte depletion with fludarabine in patients with psoriatic arthritis: clinical and immunological effects. Ann Rheum Dis 2003; 62:1112-5. [PMID: 14583577 PMCID: PMC1754350 DOI: 10.1136/ard.62.11.1112] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To obtain preliminary information on the safety and efficacy of fludarabine in PsA and analyse its immunomodulatory effects in peripheral blood and synovial tissue. METHODS 15 patients with active PsA who did not respond to DMARDs were randomly allocated to receive fludarabine every four weeks or placebo. Primary outcomes were the proportion of patients who met the ACR20 and the psoriatic arthritis response criteria (PsARC) at 16 weeks. Secondary outcomes were changes in tender or swollen joint counts and scores of the psoriasis area and severity index (PASI). Phenotypic analysis of peripheral blood mononuclear cells (PBMC), synovial immunohistochemistry, and functional analysis of PBMC were used to determine the immunomodulatory effects of fludarabine. RESULTS At 16 weeks the ACR20 criteria were met by 3/7 (43%) fludarabine treated v 0/8 placebo treated patients (p=0.08); the PsARC was achieved by 4/7 (57%) fludarabine treated v 2/8 (25%) placebo treated patients; and 3/7 (43%) fludarabine treated v 0/7 placebo treated patients had > or =20% improvement in the PASI. Marked peripheral lymphopenia involving naive (CD4(+) CD45RA(+)) and memory (CD4(+) CD45RO(+)) T cells, CD8(+) T cells, and B cells was seen in fludarabine treated patients. CONCLUSIONS In PsA fludarabine induces significant peripheral, but modest, synovial lymphopenia, and a trend towards improved clinical response.
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McElroy K, Simmonds RW, Hoffman JE, Lee DH, Orenstein J, Eisaki H, Uchida S, Davis JC. Relating atomic-scale electronic phenomena to wave-like quasiparticle states in superconducting Bi2Sr2CaCu2O8+delta. Nature 2003; 422:592-6. [PMID: 12686994 DOI: 10.1038/nature01496] [Citation(s) in RCA: 398] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2002] [Accepted: 02/14/2003] [Indexed: 11/09/2022]
Abstract
The electronic structure of simple crystalline solids can be completely described in terms either of local quantum states in real space (r-space), or of wave-like states defined in momentum-space (k-space). However, in the copper oxide superconductors, neither of these descriptions alone may be sufficient. Indeed, comparisons between r-space and k-space studies of Bi2Sr2CaCu2O8+delta (Bi-2212) reveal numerous unexplained phenomena and apparent contradictions. Here, to explore these issues, we report Fourier transform studies of atomic-scale spatial modulations in the Bi-2212 density of states. When analysed as arising from quasiparticle interference, the modulations yield elements of the Fermi-surface and energy gap in agreement with photoemission experiments. The consistency of numerous sets of dispersing modulations with the quasiparticle interference model shows that no additional order parameter is required. We also explore the momentum-space structure of the unoccupied states that are inaccessible to photoemission, and find strong similarities to the structure of the occupied states. The copper oxide quasiparticles therefore apparently exhibit particle-hole mixing similar to that of conventional superconductors. Near the energy gap maximum, the modulations become intense, commensurate with the crystal, and bounded by nanometre-scale domains. Scattering of the antinodal quasiparticles is therefore strongly influenced by nanometre-scale disorder.
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Abstract
Ankylosing spondylitis is an inflammatory disorder affecting the axial skeleton and periphery. Symptoms can often be debilitating. Current therapy for the disease include physical therapy, non-steroidal anti-inflammatory drugs (NSAIDS, anti-rheumatic disease modifying drugs (DMARDS), and the newly developed biologic agents targeting tumor necrosis factor alpha (TNF-alpha). This paper will provide a comprehensive review of these treatments which focusing on evidence based medicine for the daily clinical practice of rheumatology.
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Davis JC. The role of etanercept in ankylosing spondylitis. Clin Exp Rheumatol 2002; 20:S111-5. [PMID: 12463459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Ankylosing spondylitis is a chronic inflammatory disease that leads to significant loss of function and disability in patients. Current conventional therapies have not demonstrated improvement in axial symptoms and progressive ankylosis of the spine. The use of new biologic agents that block the actions of tumor necrosis factor-alpha have, for the first time, reported significant improvement in axial symptoms and reduction in spinal inflammation in short-term studies. Future studies with larger numbers of patients over long periods of time will eventually determine the long-term success and safety of these agents.
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Hoffman JE, McElroy K, Lee DH, Lang KM, Eisaki H, Uchida S, Davis JC. Imaging quasiparticle interference in Bi2Sr2CaCu2O8+delta. Science 2002; 297:1148-51. [PMID: 12142440 DOI: 10.1126/science.1072640] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Scanning tunneling spectroscopy of the high-Tc superconductor Bi2Sr2CaCu2O8+delta reveals weak, incommensurate, spatial modulations in the tunneling conductance. Images of these energy-dependent modulations are Fourier analyzed to yield the dispersion of their wavevectors. Comparison of the dispersions with photoemission spectroscopy data indicates that quasiparticle interference, due to elastic scattering between characteristic regions of momentum-space, provides a consistent explanation for the conductance modulations, without appeal to another order parameter. These results refocus attention on quasiparticle scattering processes as potential explanations for other incommensurate phenomena in the cuprates. The momentum-resolved tunneling spectroscopy demonstrated here also provides a new technique with which to study quasiparticles in correlated materials.
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161
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Derro DJ, Hudson EW, Lang KM, Pan SH, Davis JC, Markert JT, de Lozanne AL. Nanoscale one-dimensional scattering resonances in the CuO chains of YBa(2)Cu(3)O(6+x). PHYSICAL REVIEW LETTERS 2002; 88:097002. [PMID: 11864044 DOI: 10.1103/physrevlett.88.097002] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2001] [Indexed: 05/23/2023]
Abstract
We present scanning tunneling spectroscopy measurements of the CuO chain plane in YBa(2)Cu(3)O(6+x), showing an approximately 25 meV gap in the local density of states (LDOS) filled by numerous intragap resonances: intense peaks in LDOS spectra associated with one-dimensional, Friedel-like oscillations. We discuss how these phenomena shed light on recent results from other probes, as well as their implications for phenomena in the superconducting CuO(2) plane.
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162
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Lang KM, Madhavan V, Hoffman JE, Hudson EW, Eisaki H, Uchida S, Davis JC. Imaging the granular structure of high-Tc superconductivity in underdoped Bi2Sr2CaCu2O8+delta. Nature 2002; 415:412-6. [PMID: 11807550 DOI: 10.1038/415412a] [Citation(s) in RCA: 638] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Granular superconductivity occurs when microscopic superconducting grains are separated by non-superconducting regions; Josephson tunnelling between the grains establishes the macroscopic superconducting state. Although crystals of the copper oxide high-transition-temperature (high-Tc) superconductors are not granular in a structural sense, theory suggests that at low levels of hole doping the holes can become concentrated at certain locations resulting in hole-rich superconducting domains. Granular superconductivity arising from tunnelling between such domains would represent a new view of the underdoped copper oxide superconductors. Here we report scanning tunnelling microscope studies of underdoped Bi2Sr2CaCu2O8+delta that reveal an apparent segregation of the electronic structure into superconducting domains that are approximately 3 nm in size (and local energy gap <50 meV), located in an electronically distinct background. We used scattering resonances at Ni impurity atoms as 'markers' for local superconductivity; no Ni resonances were detected in any region where the local energy gap Delta > 50 +/- 2.5 meV. These observations suggest that underdoped Bi2Sr2CaCu2O8+delta is a mixture of two different short-range electronic orders with the long-range characteristics of a granular superconductor.
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Hoffman JE, Hudson EW, Lang KM, Madhavan V, Eisaki H, Uchida S, Davis JC. A four unit cell periodic pattern of quasi-particle states surrounding vortex cores in Bi2Sr2CaCu2O8+delta. Science 2002; 295:466-9. [PMID: 11799234 DOI: 10.1126/science.1066974] [Citation(s) in RCA: 733] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Scanning tunneling microscopy is used to image the additional quasi-particle states generated by quantized vortices in the high critical temperature superconductor Bi2Sr2CaCu2O8+delta. They exhibit a copper-oxygen bond-oriented "checkerboard" pattern, with four unit cell (4a0) periodicity and a approximately 30 angstrom decay length. These electronic modulations may be related to the magnetic field-induced, 8a0 periodic, spin density modulations with decay length of approximately 70 angstroms recently discovered in La1.84Sr0.16CuO4. The proposed explanation is a spin density wave localized surrounding each vortex core. General theoretical principles predict that, in the cuprates, a localized spin modulation of wavelength lambda should be associated with a corresponding electronic modulation of wavelength lambda/2, in good agreement with our observations.
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Zhang L, Beeler DL, Lawrence R, Lech M, Liu J, Davis JC, Shriver Z, Sasisekharan R, Rosenberg RD. 6-O-sulfotransferase-1 represents a critical enzyme in the anticoagulant heparan sulfate biosynthetic pathway. J Biol Chem 2001; 276:42311-21. [PMID: 11551899 DOI: 10.1074/jbc.m101441200] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Using recombinant retroviral transduction, we have introduced the heparin/heparan sulfate (HS) 3-O-sulfotransferase 1 (3-OST-1) gene into Chinese hamster ovary (CHO) cells. Expression of 3-OST-1 confers upon CHO cells the ability to produce anticoagulantly active HS (HS(act)). To understand how 6-OST and other proteins regulate HS(act) biosynthesis, a CHO cell clone with three copies of 3-OST-1 was chemically mutagenized. Resulting mutants that make HS but are defective in generating HS(act) were single-cell-cloned. One cell mutant makes fewer 6-O-sulfated residues. Modification of HS chains from the mutant with pure 6-OST-1 and 3'-phosphoadenosine 5'-phosphosulfate increased HS(act) from 7% to 51%. Transfection of this mutant with 6-OST-1 created a CHO cell line that makes HS, 50% of which is HS(act). We discovered in this study that (i) 6-OST-1 is a limiting enzyme in the HS(act) biosynthetic pathway in vivo when the limiting nature of 3-OST-1 is removed; (ii) HS chains from the mutant cells serve as an excellent substrate for demonstrating that 6-OST-1 is the limiting factor for HS(act) generation in vitro; (iii) in contradiction to the literature, 6-OST-1 can add 6-O-sulfate to GlcNAc residues, especially the critical 6-O-sulfate in the antithrombin binding motif; (iv) both 3-O- and 6-O-sulfation can be the final step in HS(act) biosynthesis in contrast to prior publications that concluded 3-O-sulfation is the final step in HS(act) biosynthesis; (v), in the presence of HS interacting protein peptide, 3-O-sulfate-containing sugars can be degraded into disaccharides by heparitinase digestion as demonstrated by capillary high performance liquid chromatography coupled with mass spectrometry.
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Pan SH, O'Neal JP, Badzey RL, Chamon C, Ding H, Engelbrecht JR, Wang Z, Eisaki H, Uchida S, Gupta AK, Ng KW, Hudson EW, Lang KM, Davis JC. Microscopic electronic inhomogeneity in the high-Tc superconductor Bi2Sr2CaCu2O8+x. Nature 2001; 413:282-5. [PMID: 11565024 DOI: 10.1038/35095012] [Citation(s) in RCA: 723] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The parent compounds of the copper oxide high-transition-temperature (high-Tc) superconductors are unusual insulators (so-called Mott insulators). Superconductivity arises when they are 'doped' away from stoichiometry. For the compound Bi2Sr2CaCu2O8+x, doping is achieved by adding extra oxygen atoms, which introduce positive charge carriers ('holes') into the CuO2 planes where the superconductivity is believed to originate. Aside from providing the charge carriers, the role of the oxygen dopants is not well understood, nor is it clear how the charge carriers are distributed on the planes. Many models of high-Tc superconductivity accordingly assume that the introduced carriers are distributed uniformly, leading to an electronically homogeneous system as in ordinary metals. Here we report the presence of an electronic inhomogeneity in Bi2Sr2CaCu2O8+x, on the basis of observations using scanning tunnelling microscopy and spectroscopy. The inhomogeneity is manifested as spatial variations in both the local density of states spectrum and the superconducting energy gap. These variations are correlated spatially and vary on the surprisingly short length scale of approximately 14 A. Our analysis suggests that this inhomogeneity is a consequence of proximity to a Mott insulator resulting in poor screening of the charge potentials associated with the oxygen ions left in the BiO plane after doping, and is indicative of the local nature of the superconducting state.
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Simmonds RW, Marchenkov A, Davis JC, Packard RE. Observation of the superfluid shapiro effect in a 3He weak link. PHYSICAL REVIEW LETTERS 2001; 87:035301. [PMID: 11461563 DOI: 10.1103/physrevlett.87.035301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2001] [Indexed: 05/23/2023]
Abstract
We have studied the mass currents through a superfluid 3He Josephson weak link in the presence of an externally applied ac pressure modulation. Characteristic changes in the dc mass currents are observed whenever the superfluid Josephson frequency omega(J) is an integer multiple of the ac modulation frequency omega. The measured dependencies of these current changes on ac pressure amplitude are in excellent agreement with theory describing quantum phase dynamics of superfluid 3He weak links. These results establish the superfluid analog of the superconducting Shapiro effect.
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Simmonds RW, Marchenkov A, Hoskinson E, Davis JC, Packard RE. Quantum interference of superfluid 3He. Nature 2001; 412:55-8. [PMID: 11452302 DOI: 10.1038/35083518] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Celebrated interference experiments have demonstrated the wave nature of light and electrons, quantum interference being the manifestation of wave-particle duality. More recently, double-path interference experiments have also demonstrated the quantum-wave nature of beams of neutrons, atoms and Bose-Einstein condensates. In condensed matter systems, double-path quantum interference is observed in the d.c. superconducting quantum interference device (d.c. SQUID). Here we report a double-path quantum interference experiment involving a liquid: superfluid 3He. Using a geometry analogous to the superconducting d.c. SQUID, we control a quantum phase shift by using the rotation of the Earth, and find the classic interference pattern with periodicity determined by the 3He quantum of circulation.
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Hudson EW, Lang KM, Madhavan V, Pan SH, Eisaki H, Uchida S, Davis JC. Interplay of magnetism and high-Tc superconductivity at individual Ni impurity atoms in Bi2Sr2CaCu2O8+delta. Nature 2001; 411:920-4. [PMID: 11418850 DOI: 10.1038/35082019] [Citation(s) in RCA: 289] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Magnetic interactions and magnetic impurities are destructive to superconductivity in conventional superconductors. By contrast, in some unconventional macroscopic quantum systems (such as superfluid 3He and superconducting UGe2), the superconductivity (or superfluidity) is actually mediated by magnetic interactions. A magnetic mechanism has also been proposed for high-temperature superconductivity. Within this context, the fact that magnetic Ni impurity atoms have a weaker effect on superconductivity than non-magnetic Zn atoms in the high-Tc superconductors has been put forward as evidence supporting a magnetic mechanism. Here we use scanning tunnelling microscopy to determine directly the influence of individual Ni atoms on the local electronic structure of Bi2Sr2CaCu2O8+delta. At each Ni site we observe two d-wave impurity states of apparently opposite spin polarization, whose existence indicates that Ni retains a magnetic moment in the superconducting state. However, analysis of the impurity-state energies shows that quasiparticle scattering at Ni is predominantly non-magnetic. Furthermore, we show that the superconducting energy gap and correlations are unimpaired at Ni. This is in strong contrast to the effects of non-magnetic Zn impurities, which locally destroy superconductivity. These results are consistent with predictions for impurity atom phenomena derived from a magnetic mechanism.
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Stone JH, Hoffman GS, Merkel PA, Min YI, Uhlfelder ML, Hellmann DB, Specks U, Allen NB, Davis JC, Spiera RF, Calabrese LH, Wigley FM, Maiden N, Valente RM, Niles JL, Fye KH, McCune JW, St Clair EW, Luqmani RA. A disease-specific activity index for Wegener's granulomatosis: modification of the Birmingham Vasculitis Activity Score. International Network for the Study of the Systemic Vasculitides (INSSYS). ARTHRITIS AND RHEUMATISM 2001; 44:912-20. [PMID: 11318006 DOI: 10.1002/1529-0131(200104)44:4<912::aid-anr148>3.0.co;2-5] [Citation(s) in RCA: 338] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To refine and validate the Birmingham Vasculitis Activity Score (BVAS) as a disease-specific activity index for Wegener's granulomatosis (WG). METHODS Sixteen members of the International Network for the Study of the Systemic Vasculitides (INSSYS) revised the BVAS, with 3 goals: to reduce the redundancy of some component items, to enhance its ability to capture important disease manifestations specific to WG, and to streamline the instrument for use in clinical research. We defined the items and weighted them empirically as either minor (e.g., nasal crusting = 1 point) or major (e.g., alveolar hemorrhage = 3 points). We then validated the new, disease-specific BVAS/WG in 2 simulation exercises and a clinical case series that involved 117 patients with WG. RESULTS We removed 38 items from the original BVAS, revised 9 items, and added 7 new items. Correlations between the scores on the BVAS/WG and the physician's global assessment (PGA) of disease activity were high, even when patients in remission were excluded. In the clinical case series, Spearman's rank correlation coefficient between the BVAS/WG and the PGA was r = 0.81 (95% confidence interval 0.73-0.87). The interobserver reliability using intraclass (within-case) correlation coefficients in the 2 simulation exercises was r = 0.93 for the BVAS/WG and r = 0.88 for the PGA in the first and r = 0.91 for the BVAS/WG and r = 0.88 for the PGA in the second. There was no significant observer effect in the scoring of the BVAS/WG or the PGA. The discriminant validity of the BVAS/WG was good: r = 0.73 (95% confidence interval 0.43-0.83). CONCLUSION The BVAS/WG is a valid, disease-specific activity index for WG. Tested in simulation exercises and in actual patients, the BVAS/WG correlates well with the PGA, is sensitive to change, and has good inter- and intraobserver reliability. The INSSYS will use the BVAS/WG to assess the primary outcome in a phase II/III trial of etanercept in WG.
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Davis JC, Manzi S, Yarboro C, Rairie J, Mcinnes I, Averthelyi D, Sinicropi D, Hale VG, Balow J, Austin H, Boumpas DT, Klippel JH. Recombinant human Dnase I (rhDNase) in patients with lupus nephritis. Lupus 2001; 8:68-76. [PMID: 10025601 DOI: 10.1191/096120399678847380] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Systemic lupus erythematosus (SLE) is characterized by the production of pathogenic autoantibodies to nucleoprotein antigens, including double-stranded DNA (dsDNA). The deposition of IgG dsDNA immune complexes in glomeruli is thought to be crucial for disease pathogenesis and complement activation. rhDNase catalyzes the hydrolysis of extracellular DNA and has been shown to delay the development of dsDNA antibodies, reduce proteinuria, and delay mortality in a lupus-prone murine model. We conducted a 40d, phase Ib, randomized, double-masked, placebo-controlled trial to determine the safety and pharmacokinetics of rhDNase, and to measure any changes in markers of disease activity in 17 patients with lupus nephritis. Patients were assigned to receive either: (1) 25 microg/kg rhDNase (n = 8); (2) 125 microg/kg rhDNase (n=6); or (3) placebo (n = 3) initial single intravenous (IV) dose followed by 10 subcutaneous (SC) doses. Skin biopsies performed on nine patients pre- and post-treatment were studied for immune complex deposition by immunofluorescence. Serum cytokine levels (sIL2-R, IL-6, IL-10, and TNF-alpha) were analyzed by ELISA. Cytokine secretion and antibody production were measured by ELISPOT analysis and ELISA. Serum hydrolytic activity of rhDNase was achieved after IV administration at 25 and 125 microg/kg, but not after SC administration at either dose. A t 1/2 of 3-4h was estimated from serum concentration profiles following IV administration. Serum dsDNA antibodies were unchanged (mean values: 33 IU/mL vs 39 IU/mL [pre- and post-treatment] for the 25 microg/kg group, and 74 IU/mL vs 74 IU/mL for the 125 microg/kg group, and 14 IU/mL vs 20 IU/mL for the placebo group). Complement levels (C3 and C4) and circulating immune complexes did not change appreciably during the treatment period for any of the groups. Serum cytokine profiles by ELISA revealed no changes in sIL-2 receptor, IL-6, IL-10, or TNF-alpha. There was no change in the number of cells secreting either Th1 or Th2 specific cytokines, nor in the number of cells secreting dsDNA antibodies. Neutralizing antibodies to rhDNase were not detected in serum at any time during the study. Immune complex deposition was unchanged in pre- and post-treatment in skin biopsies in both dose groups. rhDnase was well tolerated without significant adverse events following administration, and treatment was not associated with the development of neutralizing antibodies to rhDNase. Serum rhDNase concentrations capable of hydrolytic activity of rhDNase were achieved for a few hours following IV, but not SC administration. Serum markers of disease activity were unchanged during the study period.
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Davis JC, Totoritis MC, Rosenberg J, Sklenar TA, Wofsy D. Phase I clinical trial of a monoclonal antibody against CD40-ligand (IDEC-131) in patients with systemic lupus erythematosus. J Rheumatol 2001; 28:95-101. [PMID: 11196549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To investigate the safety and pharmacology of a humanized monoclonal antibody against CD40-ligand (IDEC-131) in patients with systemic lupus erythematosus (SLE). METHODS Cohorts of 3 to 5 patients with symptomatic lupus each received 0.05, 0.25, 1.0, 5.0, or 15.0 mg/kg of IDEC-131 as a single intravenous infusion. Patients were followed for 3 months to evaluate toxicity and pharmacokinetics. RESULTS This phase I, single dose, dose-escalating study was conducted in 23 patients at a single institution. All patients experienced at least 1 adverse event (AE) during a 3 month followup period, although 58 AE in 17 patients were considered possibly or probably related or of unknown relationship to treatment. No dose relationship in the distribution of AE was apparent. No infusion related cytokine-release syndrome was observed; no infusions were interrupted, and all patients completed treatment. Eight mild (grade 1 or 2) infections were reported in 8 patients. All infections were considered unrelated to drug administration and all resolved uneventfully. No patient developed detectable antibodies to IDEC-131. Flow cytometry revealed no apparent treatment related depletion of lymphocyte subsets. Pharmacokinetic analysis indicated that the maximum serum concentration and the area under the concentration curve of IDEC-131 were proportional to the dose administered. At doses between 1.0 and 15.0 mg/kg, the serum half-life ranged from 299 to 320 h. Efficacy was not formally evaluated in this single dose study. CONCLUSION IDEC-131 (humanized Mab against CD40L) administered in a single intravenous infusion at doses of 0.05-15.0 mg/kg is safe and well tolerated in patients with SLE.
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Pan SH, Hudson EW, Gupta AK, Ng K, Eisaki H, Uchida S, Davis JC. STM studies of the electronic structure of vortex cores in Bi(2)Sr(2)CaCu(2)O(8+delta). PHYSICAL REVIEW LETTERS 2000; 85:1536-1539. [PMID: 10970548 DOI: 10.1103/physrevlett.85.1536] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2000] [Indexed: 05/23/2023]
Abstract
We report on low temperature scanning tunneling microscopy (STM) studies of the electronic structure of vortex cores in Bi 2Sr 2CaCu 2O (8+delta). At the vortex core center, an enhanced density of states is observed at energies near Omega = +/-7 meV. Spectroscopic imaging at these energies reveals an exponential decay of these "core states" with a decay length of 22+/-3 A. The fourfold symmetry sometimes predicted for d-wave vortices is not seen in spectroscopic vortex images. A locally nodeless order parameter induced by the magnetic field may be consistent with these measurements.
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Simmonds RW, Marchenkov A, Vitale S, Davis JC, Packard RE. New flow dissipation mechanisms in superfluid 3He. PHYSICAL REVIEW LETTERS 2000; 84:6062-6065. [PMID: 10991124 DOI: 10.1103/physrevlett.84.6062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2000] [Indexed: 05/23/2023]
Abstract
We have studied the flow of superfluid 3He-B forced through small apertures. There are unexpectedly large dissipative currents, which can be described by two independent processes. One process involves the creation of quasiparticles within the aperture and their subsequent acceleration in the ambient pressure gradient. The second process involves the dissipative precession of a texture in a geometry-induced anisotropic order parameter. For both mechanisms we make a simple estimate of the relevant effect and find these agree well with the data.
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Gorman JD, Danning C, Schumacher HR, Klippel JH, Davis JC. Multicentric reticulohistiocytosis: case report with immunohistochemical analysis and literature review. ARTHRITIS AND RHEUMATISM 2000; 43:930-8. [PMID: 10765941 DOI: 10.1002/1529-0131(200004)43:4<930::aid-anr27>3.0.co;2-a] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This report describes the case of a patient with multicentric reticulohistiocytosis. Immunohistochemical analysis revealed prominent markers of monocyte/macrophage origin, as well as the presence of tumor necrosis factor alpha, interleukin-1beta (IL-1beta), and IL-12; the occurrence of the latter in this disease has not previously been reported. Clinical, laboratory, radiographic, and histologic findings in multicentric reticulohistiocytosis are reviewed. In addition, all published cases of multicentric reticulohistiocytosis which included reports of cytokine and immunohistochemical analysis are reviewed, and evidence for a monocyte/macrophage origin and role in disease pathogenesis is provided.
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Gorman JD, Danning C, Schumacher HR, Klippel JH, Davis JC. Multicentric reticulohistiocytosis: case report with immunohistochemical analysis and literature review. ARTHRITIS AND RHEUMATISM 2000. [PMID: 10765941 DOI: 10.1002/1529-0131(200004)43:4<930::aid-anr27>3.0.co;2-a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This report describes the case of a patient with multicentric reticulohistiocytosis. Immunohistochemical analysis revealed prominent markers of monocyte/macrophage origin, as well as the presence of tumor necrosis factor alpha, interleukin-1beta (IL-1beta), and IL-12; the occurrence of the latter in this disease has not previously been reported. Clinical, laboratory, radiographic, and histologic findings in multicentric reticulohistiocytosis are reviewed. In addition, all published cases of multicentric reticulohistiocytosis which included reports of cytokine and immunohistochemical analysis are reviewed, and evidence for a monocyte/macrophage origin and role in disease pathogenesis is provided.
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