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101.
Sarah L. Rowland-Jones Stephen H. Powis Julian Sutton Ian Mockridge Frances M. Gotch Nick Murray Ann B. Hill William M. Rosenberg John Trowsdale Andrew J. McMichael 《European journal of immunology》1993,23(8):1999-2004
In previous studies of antigen presentation through HLA-B27, we identified a healthy person whose lymphoblastoid cells do not present three B27-restricted viral epitopes to specific cytotoxic T lymphocytes (CTL), despite adequate cell surface expression of HLA-B2702 of normal sequence. Similar findings were observed in all members of his family sharing the HLA-A3-B2702 haplotype. The original donor, NW, carries HLA-B8 on his other class I haplotype, which his daughter, HW, has inherited. We now report a failure to present an HLA-B8-restricted epitope from influenza nucleoprotein following viral infection of NW cells, although exogenous added peptide is still presented normally. However, cells from HW, which do not carry the A3-B2702 haplotype, present the expected epitope after viral infection. Another B8-restricted epitope, from human immunodeficiency virus-gag, is presented equally well by both cell lines when infected with gag-vaccinia. This antigen processing phenotype does not correlate with any of the known human TAP-1 and TAP-2 polymorphisms. 相似文献
102.
An immunogold silver staining method for the light microscopic analysis of blood lymphocyte subsets with monoclonal antibodies 总被引:2,自引:0,他引:2
This paper introduces an immunogold silver staining procedure for the identification of human lymphocyte subpopulations in optical microscopy. The described procedure is performed on cells in suspension (peripheral mononuclear cells or blood buffy-coat cells) and uses conventional antilymphocytic monoclonal antibodies (OKT3, OKT4, OKT8, OKIa1) followed by gold-labeled secondary antibodies (GAM G30 or G40) and silver sensitization. It ends with the preparation of permanent records (smears or cytocentrifuge preparations) which are counterstained with standard panoptic Wright or May-Grünwald Giemsa stain. In all cases, the surface antigens appear as numerous black dots on the lymphocytes, with a strong labeling reaction that allows one to clearly distinguish between negative and positive cells. The comparison with immunofluorescence microscopy in normal individuals and in patients indicates that this new immunostaining technic is specific and more sensitive. It has the advantages of using small amounts of blood (1 mL per test), of being rapid (three hours), and of allowing the simultaneous immunophenotypic and morphologic evaluation on smears. This makes it suitable for the analysis of other biologic specimens not already accessible with immunofluorescence. The labeled preparations apparently can be stored indefinitely, and are thus useful for longitudinal studies in the same patient. Finally, the method does not require sophisticated equipment and may be subjected to automated analysis. 相似文献
103.
Undar A Zapanta CM Reibson JD Souba M Lukic B Weiss WJ Snyder AJ Kunselman AR Pierce WS Rosenberg G Myers JL 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2005,51(1):56-59
Unreliable quantification of flow pulsatility has hampered many efforts to assess the importance of pulsatile perfusion. Generation of pulsatile flow depends upon an energy gradient. It is necessary to quantify pressure flow waveforms in terms of hemodynamic energy levels to make a valid comparison between perfusion modes during chronic support. The objective of this study was to quantify pressure flow waveforms in terms of energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE) levels in an adult mock loop using a pulsatile ventricle assist system (VAD). A 70 cc Pierce-Donachy pneumatic pulsatile VAD was used with a Penn State adult mock loop. The pump flow rate was kept constant at 5 L/min with pump rates of 70 and 80 bpm and mean aortic pressures (MAP) of 80, 90, and 100 mm Hg, respectively. Pump flows were adjusted by varying the systolic pressure, systolic duration, and the diastolic vacuum of the pneumatic drive unit. The aortic pressure was adjusted by varying the systemic resistance of the mock loop EEP (mm Hg) = (integral of fpdf)/(integral of fdt) SHE (ergs/cm3) = 1,332 [((integral of fpdt)/(integral of fdt))--MAP] were calculated at each experimental stage. The difference between the EEP and the MAP is the extra energy generated by this device. This difference is approximately 10% in a normal human heart. The EEP levels were 88.3 +/- 0.9 mm Hg, 98.1 +/- 1.3 mm Hg, and 107.4 +/- 1.0 mm Hg with a pump rate of 70 bpm and an aortic pressure of 80 mm Hg, 90 mm Hg, and 100 mm Hg, respectively. Surplus hemodynamic energy in terms of ergs/cm3 was 11,039 +/- 1,236 ergs/cm3, 10,839 +/- 1,659 ergs/cm3, and 9,857 +/- 1,289 ergs/cm3, respectively. The percentage change from the mean aortic pressure to EEP was 10.4 +/- 1.2%, 9.0 +/- 1.4%, and 7.4 +/- 1.0% at the same experimental stages. Similar results were obtained when the pump rate was changed from 70 bpm to 80 bpm. The EEP and SHE formulas are adequate to quantify different levels of pulsatility for direct and meaningful comparisons. This particular pulsatile VAD system produces near physiologic hemodynamic energy levels at each experimental stage. 相似文献
104.
A 2-week efficacy and safety study of eszopiclone in elderly patients with primary insomnia 总被引:6,自引:0,他引:6
STUDY OBJECTIVES: Evaluate the efficacy of eszopiclone in primary insomnia. DESIGN/SETTING: Randomized, double-blind, placebo-controlled multicenter in outpatient setting with weekly visits. PARTICIPANTS: Two-hundred thirty one men and women aged 65 to 85 years (mean age 72.3 years) with primary insomnia, as defined by the Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition. INTERVENTIONS: Eszopiclone 1 mg (n = 72), eszopiclone 2 mg (n = 79), or placebo (n = 80) nightly for 2 weeks. MEASUREMENTS/RESULTS: Efficacy was assessed using an interactive voice response system. Following the predefined hierarchical testing strategy, the eszopiclone 2-mg group had a significantly shorter sleep latency compared with placebo over the double-blind period (P = .0034). The eszopiclone 2-mg group had significantly longer total sleep time (P = .0003) and eszopiclone 1-mg group had significantly shorter sleep latency (P < or = .012) compared with placebo. The eszopiclone 1-mg group was not significantly different from placebo on total sleep time or any other secondary efficacy endpoint. Secondary analyses indicated that the eszopiclone 2-mg group had significantly less wake after sleep onset; significantly fewer and shorter in duration daytime naps; and significantly higher ratings of sleep quality and depth, daytime alertness, and sense of physical well-being compared with placebo (P < .05). Eszopiclone was well tolerated. The most frequent treatment-related adverse event was unpleasant taste. CONCLUSION: Nightly treatment with eszopiclone 1 mg effectively induced sleep, while the 2-mg dose was effective in inducing and maintaining sleep. Eszopiclone was well tolerated in elderly patients with primary insomnia, and the sleep efficacy was accompanied by significantly less napping and significantly higher ratings of daytime alertness, sense of physical well-being, and several quality-of-life parameters at the higher dose. 相似文献
105.
C Rosenberg Z Mustacchi A Braz I J Arnhold T H Chu J Carnevale O Frota-Pessoa 《American journal of medical genetics》1984,19(1):183-188
The 16-year old girl studied here had ambiguous external genitalia, ie, enlarged clitoris, pseudo vagina, and rudiments of Wolffian tubes. Her karyotype was 46,XY and she was H-Y antigen-positive. In spite of absence of gonadal tissue, genital virilization suggests presence of testes during embryogenesis. This patient is compared to 20 others with testicular regression from the literature. Autosomal-recessive inheritance of this condition is proposed. 相似文献
106.
C.Raymond Zeiss Roy Patterson Jacob J. Pruzansky Michael M. Miller Michael Rosenberg Doris Levitz 《The Journal of allergy and clinical immunology》1977,60(2):96-103
This report describes a spectrum of respiratory symptoms in workers exposed to trimellitic anhydride (TMA), a biologically reactive chemical used in the plastics industry. Fourteen workers who had worked on a unit which synthesized TMA were evaluated by clinical and immunologic methods. Respiratory syndromes induced by TMA inhalation included asthma and rhinitis of the immediate type, late onset asthma with systemic symptoms, and airway irritation. TMA was shown to couple rapidly to human serum albumin, forming an immunoreactive hapten-protein complex. The workers' immunologic reactivity to this complex could be quantitated and correlated with the three respiratory syndromes. The asthma-rhinitis syndrome was mediated by IgE antibody specific for the TMA hapten. The syndrome of late onset asthma with systemic symptoms was accompanied by elevated levels of TMA-specific IgG antibody. Rheumatoid factor in high titer was found in one worker with IgE-mediated asthma and in two workers with asthma of late onset. Lymphocyte reactivity of TMA-HSA was demonstrated in three workers representative of the three clinical syndromes. Leukocyte histamine release was demonstrated to TMA-HSA in one worker with high levels of IgE antibody specific for TMA-HSA who had severe symptoms of acute rhinitis and asthma. 相似文献
107.
A role for antigen in the generation of fully mature splenic type B cells has been shown. In adoptive transfer experiments, cells from bone marrow or fetal liver required a longer period to give an anti-sheep red blood cell plaque-forming cell (PFC) response than those from spleen. This delay was not overcome by allowing the cells a 7-day sojourn in the irradiated host before antigen challenge. A two-stage protocol was designed in which the in vivo generation of fully mature cells could be measured by their ability to give PFC in lipopolysaccharide-stimulated cultures in vitro. These experiments showed that a critical factor which influences the final differentiation of bone marrow or fetal liver cells into mature, splenic type B cells is exposure to antigen. 相似文献
108.
109.
Dreyer B Tranebjaerg L Rosenberg T Weston MD Kimberling WJ Nilssen O 《European journal of human genetics : EJHG》2000,8(7):500-506
Usher syndrome type II is an autosomal recessive disorder, characterised by stable hearing impairment from childhood and progressive retinitis pigmentosa from the late teens. Mutations in the USH2A gene, located on 1q41, were recently shown to be responsible for Usher syndrome type IIa. We have investigated the molecular pathology of Usher type II by screening the USH2A gene for mutations in 31 unrelated patients from Denmark and Norway. Besides the frequent 2299delG mutation, which accounted for 44% of the disease alleles, a heterogeneous spectrum of mutations was identified. Sixteen new, putative disease-causing mutations were detected, of which 12 were private and four were shared by unrelated patients. The disease-causing mutations were scattered throughout the gene and included six nonsense and seven missense mutations, two deletions and one small insertion. In addition, six non-pathogenic polymorphisms were identified. All missense mutations resulted in major amino acid side-chain alterations. Four missense mutations affected the N-terminal part of USH2A, whereas three missense mutations affected the laminin-type epidermal growth factor-like (LE) domain. The structural consequences of the mutations affecting the LE domain are discussed in relation to the three-dimensional structure of a LE-module of the mouse laminin gamma1 chain. 相似文献
110.