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Rensing SA, Lang D, Zimmer AD, Terry A, Salamov A, Shapiro H, Nishiyama T, Perroud PF, Lindquist EA, Kamisugi Y, Tanahashi T, Sakakibara K, Fujita T, Oishi K, Shin-I T, Kuroki Y, Toyoda A, Suzuki Y, Hashimoto SI, Yamaguchi K, Sugano S, Kohara Y, Fujiyama A, Anterola A, Aoki S, Ashton N, Barbazuk WB, Barker E, Bennetzen JL, Blankenship R, Cho SH, Dutcher SK, Estelle M, Fawcett JA, Gundlach H, Hanada K, Heyl A, Hicks KA, Hughes J, Lohr M, Mayer K, Melkozernov A, Murata T, Nelson DR, Pils B, Prigge M, Reiss B, Renner T, Rombauts S, Rushton PJ, Sanderfoot A, Schween G, Shiu SH, Stueber K, Theodoulou FL, Tu H, Van de Peer Y, Verrier PJ, Waters E, Wood A, Yang L, Cove D, Cuming AC, Hasebe M, Lucas S, Mishler BD, Reski R, Grigoriev IV, Quatrano RS, Boore JL. The Physcomitrella Genome Reveals Evolutionary Insights into the Conquest of Land by Plants. Science 2007; 319:64-9. [DOI: 10.1126/science.1150646] [Citation(s) in RCA: 1452] [Impact Index Per Article: 85.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Rance G, Barker E, Mok M, Dowell R, Rincon A, Garratt R. Speech Perception in Noise for Children with Auditory Neuropathy/Dys-Synchrony Type Hearing Loss. Ear Hear 2007; 28:351-60. [PMID: 17485984 DOI: 10.1097/aud.0b013e3180479404] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To evaluate the effect of background noise on speech perception in children with auditory neuropathy/dys-synchrony (AN/AD) type hearing loss. DESIGN Open and closed-set speech perception abilities were assessed in 12 school-age children who had been diagnosed with AN/AD in infancy. Data were also obtained from a cohort of subjects with sensorineural (SN) hearing loss and from a group of normal-hearing children. RESULTS Closed-set speech understanding was more affected by the presence of a competing signal in the hearing impaired than in the normal-hearing subjects. The mean S/N ratio required to identify a spondee in noise was -11.5 +/- 2.0 dB for the normal group, whereas the ratio required for the SN group was -5.4 +/- 5.1 dB and for the AN/AD group was -2.5 +/- 4.7 dB. Closed-set perception in noise was not significantly different for the AN/AD children and their SN counterparts although there was a trend toward poorer performance in the AN/AD group. The effect of background noise on open-set speech perception was also similar across hearing-impaired subjects although again, the AN/AD cohort tended to show greater difficulties in noise than their SN peers. CONCLUSIONS Listening in background noise was more difficult for our group of children with AN/AD-type hearing loss than for their normal-hearing peers. However, the noise effects were not consistent across subjects and some children demonstrated reasonable perceptual ability at low signal-to-noise ratios. The ways in which speech understanding is affected by competing signals may be different for different types of hearing deficit, but the results of this investigation indicate that significant perceptual disruption occurs both in children with auditory neuropathy/dys-synchrony and sensorineural type hearing loss.
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Barker E, Murison P, Macchiarini P, Jones A, Otto C, Rothkoetter HJ, Haverson K, Bailey M, Birchall M, Stokes C. Early immunological changes associated with laryngeal transplantation in a major histocompatibility complex-matched pig model. Clin Exp Immunol 2007; 146:503-8. [PMID: 17100771 PMCID: PMC1810420 DOI: 10.1111/j.1365-2249.2006.03232.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Laryngeal transplantation is an increasingly viable proposition for patients with irreversible diseases of the larynx. One human transplant has been performed successfully, but many questions remain before routine transplantation can begin. In order to measure the immunological changes in mismatched transplants, it is first necessary to know the immediate combined effects of ischaemia-reperfusion injury (IRI) plus the added insult of major surgery in a fully matched setting. We measured the changes in immunologically active mucosal cells following 3 h of cold ischaemia and 8 h of in situ reperfusion in a major histocompatibility complex (MHC)-matched minipig model (n = 4). Biopsies were prepared for quantitative, multiple-colour immunofluorescence histology. The number of immunologically active cells was significantly altered above (supraglottis) and below (subglottis) the vocal cords following transplantation and reperfusion (P < 0.05, P < 0.001, respectively). However, the direction of the change differed between the two subsites: cell numbers decreased post-transplant in the supraglottis and increased in the subglottis. Despite the statistical evidence for IRI, these changes were less than the large normal inter- and intrapig variation in cell counts. Therefore, the significance of IRI in exacerbating loss of function or rejection of a laryngeal allograft is open to question. Longer-term studies are required.
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Barker E, Haverson K, Stokes CR, Birchall M, Bailey M. The larynx as an immunological organ: immunological architecture in the pig as a large animal model. Clin Exp Immunol 2006; 143:6-14. [PMID: 16367928 PMCID: PMC1809556 DOI: 10.1111/j.1365-2249.2005.02950.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2005] [Indexed: 12/01/2022] Open
Abstract
The larynx is a mucosal organ positioned at the divergence of the respiratory and digestive tracts. It is exposed to a wide variety of environmental components, including foreign antigens, tobacco smoke, laryngopharyngeal reflux and pollutants. The mucosal immune system generates either active immune responses or tolerance, depending on the nature of the antigen and we hypothesize that the larynx is important organ for immunological decision-making in the airway. Because the pig is an ideal large animal model in which to explore laryngological research questions, such as those relating to laryngeal transplantation, we investigated the normal mucosal immunology of the porcine larynx. Pig larynges and tracheae were processed and prepared for bright-field microscopy and quantitative, multiple-colour immunofluorescence histology using pig-specific monoclonal antibodies. There was an abundance of immunologically active cells within the mucosa of the larynx and trachea of both the newborn and adult animal. Specifically, major histocompatibility complex class II (MHC class II+) cells, CD4+ and CD8+ cells were identified, although regional differences in numbers were apparent: specifically, the supraglottis contained fewer immunologically relevant cells than other sites sampled. There was a significant correlation between the numbers of MHC class II+ and CD4+ cells indicating co-ordinate regulation and therefore functional local interactions. The presence of such an immunological structure suggests that the larynx may have important functions in respiratory immunology and that it may trigger strong alloresponses after laryngeal transplantation.
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Inman CF, Rees LEN, Barker E, Haverson K, Stokes CR, Bailey M. Validation of computer-assisted, pixel-based analysis of multiple-colour immunofluorescence histology. J Immunol Methods 2005; 302:156-67. [PMID: 15992812 DOI: 10.1016/j.jim.2005.05.005] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2004] [Revised: 04/26/2005] [Accepted: 05/18/2005] [Indexed: 11/15/2022]
Abstract
Developments in immunohistology allow the routine simultaneous use on tissue sections of three monoclonal antibodies, tagged with different fluorochromes. Such staining can identify seven different cell populations and the limiting factor is rapid, reliable and reproducible analysis. Future reliance on computer-assisted analysis of digitised images depends on validation against manual counting, often viewed as the 'gold standard'. In this study images were digitised from sections of normal porcine skin, inflamed skin and tonsil, simultaneously stained with three monoclonal antibodies. Combinations of staining were quantified by four manual counts and by pixel-based area measurement. On individual images, the correlation between automated and manual measurements was poor. Despite this, the concordance between manual and automated measurements in the means and variances of tissues was good, and both techniques identified the same changes in inflamed versus normal tissues. In addition, pixel-based counting permitted statistical analysis of co-localisation of cell types in tissue sections. We conclude that automated counting is acceptable for the assessment of tissues, is faster and provides less opportunity for observer variation than manual counting. We also demonstrate that the technique is applicable where more than three fluorochromes are used such that manual counting becomes essentially impossible.
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Duong DN, Schempp C, Barker E, Cupples S, Pierce P, Ryan-Wenger N, Turner M, Young-McCaughan S. Developing Military Nursing Research Priorities. Mil Med 2005; 170:362-5. [PMID: 15974200 DOI: 10.7205/milmed.170.5.362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Congress established the TriService Nursing Research Program (TSNRP) in 1992 to serve the nursing research needs of the military. The TSNRP advances the science of military nursing to support mission readiness and deployment, improves the health and quality of life of military personnel, and provides optimal nursing care in settings worldwide. In 1995, the TSNRP Advisory Council commissioned the Institute of Medicine to make recommendations on management, research funding areas, resource allocation, and objectives. In 1996, the committee issued its report, The Program for Research in Military Nursing: Progress and Future Direction. A principal recommendation was that the TSNRP hold regular research priority-setting conferences. In response, since 2000, the TSNRP has held three conferences. This article follows up the Institute of Medicine report and summarizes the results of those conferences. The article describes conference processes, constituents, and conclusions and outlines future TSNRP research directions.
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Inman C, Barker E, Haverson K, Stokes C, Bailey M. 42. Comparison of manual and computer-assisted analysis of multiple-colour immunofluorescence histology. Res Vet Sci 2003. [DOI: 10.1016/s0034-5288(03)90041-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Warnke E, Barker E, Brilman A, Young C, Cook L. Inheritance of superoxide dismutase ( Sod-1) in a perennial x annual ryegrass cross and its allelic distribution among cultivars. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2002; 105:1146-1150. [PMID: 12582892 DOI: 10.1007/s00122-002-1007-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2001] [Accepted: 03/07/2002] [Indexed: 05/18/2023]
Abstract
Identifying annual ryegrass contamination in perennial ryegrass seed lots has been of major interest in seed-testing laboratories and for seed regulatory agencies in the USA for many years. This study was conducted to characterize a superoxide dismutase locus ( Sod-1) and determine its potential to distinguish cultivated ryegrass species. The inheritance of Sod-1 was evaluated in a three-generation annual x perennial ryegrass mapping population and segregation fitted an expected 1:2:1 ratio for a single locus with two alleles. The molecular form of the Sod-1 locus was determined by H(2)O(2) and KCN inhibitor assays which indicated that the Sod-1, and a second independently segregating Sod-2, locus were both Cu/ZnSod enzymes. The common alleles at the Sod-1 locus were scored in 13 annual and 24 perennial ryegrass cultivars to determine the potential of using this locus for species separation. The Sod-1b allele was homozygous in 98% of perennial ryegrass individuals from 24 cultivars, but those not 100% homozygous for Sod-1b were seed lots with unknown contamination from annual ryegrass. These results indicate that the Sod-1b allele in the homozygous condition is a good indicator of perenniality. All eight annual ryegrass cultivars originating in Europe or Asia had a low frequency of Sod-1b homozygous individuals or none at all. The five cultivars originating in the Western Hemisphere, however, had genotype frequencies for homozygous Sod-1b of up to 56%. The potential of the Sod-1 locus to serve as a test to separate the two growth forms depends on the source of the annual-type contamination.
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Inoue Y, King TE, Barker E, Daniloff E, Newman LS. Basic fibroblast growth factor and its receptors in idiopathic pulmonary fibrosis and lymphangioleiomyomatosis. Am J Respir Crit Care Med 2002; 166:765-73. [PMID: 12204879 DOI: 10.1164/rccm.2010014] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Basic fibroblast growth factor (bFGF) is a potent mitogenic factor for smooth muscle cells, myofibroblasts, and fibroblasts, proliferation of which is a hallmark of idiopathic pulmonary fibrosis (IPF) and lymphangioleiomyomatosis (LAM). Mast cells produce bFGF and have been associated with pulmonary fibrosis. We hypothesize that smooth muscle cell/myofibroblast-like cells will be spatially associated with bFGF-containing mast cells and that bFGF receptors will be expressed on the effector cells in IPF and LAM. We performed quantitative immunohistochemistry for bFGF, mast cell tryptase, smooth muscle actin for smooth muscle cell/myofibroblast-like cells, and fibroblast growth factor receptors (Flg, Bek) and measured collagen and elastic fiber in lung sections from IPF (n = 14), LAM (n = 9), and control lung (n = 10). IPF and LAM lung contained more smooth muscle cell/myofibroblast-like cells than did control lung. bFGF-containing mast cells were abundant both in IPF and LAM and were associated with collagen, elastic fibers, and smooth muscle cell/myofibroblast-like cells in IPF. Flg was expressed on epithelial cells, endothelial cells, smooth muscle cell/myofibroblast-like cells, and macrophages in IPF. In LAM, Flg was expressed on epithelial cells adjacent to smooth muscle cell/myofibroblast-like cell aggregates. Bek was expressed dominantly on smooth muscle cell/myofibroblast-like cells in LAM and on smooth muscle cell/myofibroblast-like cells as well as neutrophils in IPF. These data suggest that mast cell-derived bFGF might exert fibrogenic, proliferative effects on smooth muscle cell/myofibroblast-like cells through its receptors.
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Barker E. "A sneaky, cowardly enemy": Tampa's yellow fever epidemic of 1887-88. TAMPA BAY HISTORY 2001; 8:4-22. [PMID: 11618196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Barker E. Increase your visibility! RN 2001; 64:41-2. [PMID: 11249420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Wrzesinski S, Séguin R, Liu Y, Domville S, Planelles V, Massa P, Barker E, Antel J, Feuer G. HTLV type 1 Tax transduction in microglial cells and astrocytes by lentiviral vectors. AIDS Res Hum Retroviruses 2000; 16:1771-6. [PMID: 11080825 DOI: 10.1089/08892220050193290] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Infection with human T cell leukemia virus type 1 (HTLV-1) can result in the development of HAM/TSP, a nonfatal, chronic inflammatory disease involving neuronal degeneration and demyelination of the central nervous system. Elevated levels of the proinflammatory cytokines tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and IL-1 observed in the cerebrospinal fluid of HAM-TSP patients suggest that cytokine dysregulation within the CNS is involved in neuropathogenesis. HTLV-1 infection and enhanced expression of TNF-alpha by microglial cells, astrocytes, and macrophages has been hypothesized to lead to the destruction of myelin and oligodendrocytes in the CNS. Although the association of HTLV-2 infection and development of neurological disease is more tenuous, HTLV-2 has also been found to be associated with peripheral neuropathies. To investigate the roles of HTLV Tax(1) and Tax(2) in the induction of cytokine disregulation in these cell types, we are currently developing gene delivery vectors based on human immunodeficiency virus type-1 (HIV-1) capable of stably coexpressing the HTLV-1 or -2 tax and eGFP reporter genes in primary human cells. Transduction frequencies of up to 50%, as assessed by eGFP expression, can be achieved in human monocyte-derived macrophages and in explanted cultures of human microglia. Preliminary data suggest that Tax(1) expression is sufficient to up-regulate the proinflammatory cytokine profile in explanted human microglial cells. Future experiments will compare and evaluate the effect of tax(1) and tax(2) gene expression on the cellular proinflammatory cytokine expression profile, as well as demonstrate the effects of transducing human fetal astrocytes and PBMC-derived macrophages.
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Hamada H, Vallyathan V, Cool CD, Barker E, Inoue Y, Newman LS. Mast cell basic fibroblast growth factor in silicosis. Am J Respir Crit Care Med 2000; 161:2026-34. [PMID: 10852784 DOI: 10.1164/ajrccm.161.6.9812132] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
To investigate the role of mast cells (MC) and their fibrogenic growth factors in silicosis, we performed quantitative immunohistochemistry for MC tryptase and for basic fibroblast growth factor (bFGF) in lung tissue from silicotic and control subjects. Anti-bFGF antibody was bound to lung MC, basement membrane, endothelial cells, and smooth-muscle cells. Morphometric analysis revealed that the volume density (V(v)) of MC was increased in silicotic lung and that the V(v) of bFGF-positive (bFGF(+)) cells was significantly higher than normal in silicotic lung. Most MC contained bFGF (rho = 0.88, p < 0.001). The V(v) of collagen/reticulin fibers was increased in silicosis and correlated with the V(v) of bFGF(+) cells (rho = 0.81, p < 0.001). Immature silicotic nodules contained bFGF(+) MC throughout the loose array of collagen/reticulin fibers. In large, mature nodules, the density of collagen/reticulin fibers was higher, and bFGF(+) MC were found only in the nodule periphery. Because of this circumferential MC alignment in silicotic nodules, we observed a negative correlation between the V(v) of bFGF(+) MC and the density of collagen/reticulin fibers in silicotic nodules (rho = -0.80, p < 0.001) and between the V(v) of all other nodule-associated cells and the density of collagen/reticulin fibers in the hypocellular nodule centers (rho = -0.84, p < 0.001). We conclude that MC that produce bFGF may play an important role in the development of silicosis.
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Barker E, Schiffer SW, Rychnovsky J. Transitioning from the military. ADVANCE FOR NURSE PRACTITIONERS 2000; 8:33. [PMID: 15658204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
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Farris GM, Newman LS, Frome EL, Shou Y, Barker E, Habbersett RC, Maier L, Smith HN, Marrone BL. Detection of beryllium sensitivity using a flow cytometric lymphocyte proliferation test: the Immuno-Be-LPT. Toxicology 2000; 143:125-40. [PMID: 10755700 DOI: 10.1016/s0300-483x(99)00167-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Measurement of lymphocyte proliferation to detect hypersensitivity to beryllium (Be-LPT) in vitro is done presently using a method based on tritiated thymidine incorporation. Although this method is sensitive it gives no information on cell viability or responding lymphocyte subsets. We have developed reliable and simple flow cytometric assays for lymphocyte proliferation testing (Immuno-Be-LPT) by combining immunophenotyping with bromodeoxyuridine (BrdU) incorporation or DNA content using propidium iodide (PI) or 4'6'-diimidazolin-2-phenylindole (DAPI). Evaluation of beryllium-induced lymphocyte proliferation in blood cells from seven patients with chronic beryllium disease (CBD) and 120 beryllium workers by both the Bc-LPT and the Immuno-Be-LPT showed agreement between the tests. The Immuno-Bc-LPT provided additional information about the specific type of lymphocytes responding. CD4+ lymphocytes proliferated in response to beryllium in blood samples from all seven CBD individuals and CD8+ lymphocytes proliferated in six of the seven. Four beryllium workers without CBD had positive responses to beryllium primarily in the CD8+ cells. The use of the individual's own plasma supported a greater beryllium or tetanus-induced proliferation of CD4+ lymphocytes when compared to commercial human serum. The response of CD4+ lymphocytes measured in the Immuno-Be-LPT may provide a new marker for the diagnosis of CBD.
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MESH Headings
- Antibodies, Monoclonal
- Antigens, CD/biosynthesis
- Antigens, Differentiation, T-Lymphocyte/biosynthesis
- Beryllium/toxicity
- Biomarkers
- Bromodeoxyuridine/metabolism
- Cell Division/drug effects
- Chronic Disease
- DNA/biosynthesis
- DNA/metabolism
- Flow Cytometry
- Fluorescent Dyes
- Humans
- Lectins, C-Type
- Light
- Lymphocytes/drug effects
- Occupational Diseases/immunology
- Phenotype
- Scattering, Radiation
- T-Lymphocytes, Helper-Inducer/drug effects
- T-Lymphocytes, Helper-Inducer/immunology
- T-Lymphocytes, Regulatory/drug effects
- T-Lymphocytes, Regulatory/immunology
- Tetanus Toxoid/pharmacology
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Charmasson S, Barker E, Calmet D, Pruchon AS, Thébault H. Long-term variations of man-made radionuclide concentrations in a bio-indicator Mytilus galloprovincialis from the French Mediterranean coast. THE SCIENCE OF THE TOTAL ENVIRONMENT 1999; 237-238:93-103. [PMID: 10568268 DOI: 10.1016/s0048-9697(99)00127-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Results from a 14-year monitoring (1984-1997) of man-made radionuclide (137Cs and 106Ru) levels in Mytilus galloprovincialis collected monthly on the French Mediterranean coast are presented. In this area sources of man-made radionuclides are on the one hand atmospheric fallout from both the past nuclear testings and the Chernobyl accident and on the other hand discharges from nuclear installations located on the Rhône River banks, especially those from the spent nuclear fuel reprocessing plant in Marcoule. Long-term variations of radionuclide concentrations in Mytilus demonstrated seasonal variations which are linked to the reproductive cycle of these organisms as well as to variations in land-based inputs of man-made radionuclides. A comparative study of these seasonal variations has been carried out with the aid of spectral analysis. Due to differences in released activities and discharge patterns, flow rates appear to govern mainly the 137Cs variations in the Rhône waters, whereas 106Ru variations are driven by the discharges. In the area under the influence of the Rhône outflow, 137Cs variations in mussels are characterized by seasonal variations which are themselves inversely correlated with variations of 137Cs concentrations in Rhône waters. This cyclic component seems to be closely linked to the mussel reproductive cycle. The possible influence of other parameters is discussed.
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Barker E, Bossart KN, Fujimura SH, Levy JA. The role of CD80 and CD86 in enhancing CD8(+) cell suppression of HIV replication. Cell Immunol 1999; 196:95-103. [PMID: 10527561 DOI: 10.1006/cimm.1999.1551] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
CD8(+) cells activated in the presence of autologous macrophages (Mphi) have an increased ability to suppress HIV replication compared to the same cells stimulated in the absence of Mphi. Blocking the B7 molecules decreases the ability of Mphi to increase CD8(+) cell antiviral activity. In the present study CD8(+) cells exposed to purified forms of both the CD80 and the CD86 molecules during stimulation with anti-CD3 antibodies (Ab) had a greater ability to suppress HIV replication than CD8(+) cells exposed to anti-CD3 Ab alone. The addition of anti-CD86 blocking Ab, but not anti-CD80 blocking Ab, to Mphi decreased their ability to enhance CD8(+) cell suppression of HIV replication. Moreover, anti-CD86 Ab and not anti-CD80 Ab blocked the production of IL-2 by CD8(+) cells stimulated in the presence of Mphi. The incapacity of anti-CD80 Ab to block the enhanced antiviral activity and IL-2 production of CD8(+) cells stimulated in the presence of Mphi was not due to the inability of this Ab to function since anti-CD80 Ab are able to block proliferation of CD8(+) cells cultured in the presence of Mphi. Thus, while both B7 molecules can deliver a costimulatory signal sufficient to increase CD8(+) cell antiviral activity, CD86 appears to be the molecule that serves as the costimulatory molecule on Mphi to enhance CD8(+) cell suppression of HIV replication. The difference in use of CD86 over CD80 molecules on Mphi by CD8(+) cells mediating the antiviral suppressing activity most likely results from a higher number of Mphi expressing the CD86 molecule compared with the CD80 molecule. This information offers a possible therapeutic approach to increase CD8(+) cell anti-HIV response.
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Barker E. CD8+ cell-derived anti-human immunodeficiency virus inhibitory factor. J Infect Dis 1999; 179 Suppl 3:S485-8. [PMID: 10099125 DOI: 10.1086/314808] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
CD8+ cells in human immunodeficiency virus (HIV)-infected individuals develop the ability to control HIV replication not only by destruction of the infected cells but also by controlling the virus in a noncytotoxic fashion that leaves the infected cell functionally intact. The CD8+ noncytotoxic response is mediated by a novel soluble factor known as CD8+ cell antiviral factor (CAF). CAF suppresses HIV replication in the infected cell at the level of viral transcription by interrupting the ability of Tat or host cellular factors to interact with the HIV long terminal repeats. Unlike some strain-specific anti-HIV cytokines, CAF is active against many different virus isolates, including HIV strains that are nonsyncytium- and syncytium-inducing. Of importance, the ability of CD8+ cells to produce CAF and suppress HIV replication plays a critical role in preventing disease progression following HIV infection.
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Barker E. Brain attack! A call to action. RN 1999; 62:54-7. [PMID: 10418526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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Barker E. Life care planning. RN 1999; 62:58-61. [PMID: 10205567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Barker E, Bossart KN, Levy JA. Differential effects of CD28 costimulation on HIV production by CD4+ cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1998; 161:6223-7. [PMID: 9834109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We have observed that CD28 costimulation of CD4+ cells can have differential effects on HIV replication. Triggering the CD28 molecule on peripheral blood CD4+ cells during stimulation with anti-CD3 Abs enhances virus production following acute infection with HIV. Endogenous virus production in CD4+ cells from HIV-infected individuals is also increased by this procedure. The enhanced virus production occurs equally when anti-CD28 Abs and soluble forms of the natural ligands for CD28, CD80Ig, and CD86Ig are used to trigger CD28 on CD4+ cells during stimulation. This increased virus replication is observed only when the source of CD28 costimulation is removed immediately after stimulation and before infection. Continual exposure of CD4+ cells to anti-CD3 and CD28 Ab beads following acute infection prevents virus production. These findings may have relevance to therapeutic approaches aimed at inhibiting HIV replication by CD28 costimulation.
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Barker E. Sex; death in agony: AIDS reversed. S Afr Med J 1998; 88:1362. [PMID: 9861933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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Greco G, Barker E, Levy JA. Differences in HIV replication in CD4+ lymphocytes are not related to beta-chemokine production. AIDS Res Hum Retroviruses 1998; 14:1407-11. [PMID: 9824318 DOI: 10.1089/aid.1998.14.1407] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
CD4+ T lymphocytes from different donors vary in their ability to replicate different isolates of HIV. Beta-chemokines have been shown to reduce the rate of HIV replication in cultured cells. We now demonstrate, using CD4+ cells from 19 different donors, that the variations in viral replication observed in CD4+ lymphocytes are not due to endogenous production of beta-chemokines by the cells. Instead of finding a correlation of high-level beta-chemokine production with low-level replication of virus, we found either no consistent relationship between these two parameters or a correlation between high-level beta-chemokine production and high-level virus replication. This observation was made with both chemokine-sensitive and chemokine-resistant HIV isolates. Thus, other mechanisms appear to be involved in the variability in HIV replication in cultured CD4+ cells.
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Barker E, Mackewicz CE, Reyes-Terán G, Sato A, Stranford SA, Fujimura SH, Christopherson C, Chang SY, Levy JA. Virological and immunological features of long-term human immunodeficiency virus-infected individuals who have remained asymptomatic compared with those who have progressed to acquired immunodeficiency syndrome. Blood 1998; 92:3105-14. [PMID: 9787145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Infection with the human immunodeficiency virus (HIV) leads to a decrease in CD4(+) T cells and disease progression within a decade of seroconversion. However, a small group of infected people, despite being infected by HIV for 10 or more years, remain clinically asymptomatic and have stable CD4(+) cell counts without taking antiretroviral medication. To determine why these individuals, known as long-term survivors (LTS), remain healthy, the hematological profiles, viral load and properties, HIV coreceptor genotype, and anti-HIV immune responses of these people were compared with those of individuals who have progressed to disease (Progressors) over the same time period. Unlike Progressors, LTS have a low circulating viral load and a low number of HIV-infected cells. These differences in the levels of the viral load were not associated with a dominant biologic viral phenotype, varying growth kinetics of the virus, mutation in the cellular CCR5 gene, or the presence of neutralizing antibodies. Importantly, the difference in viral load could be explained by the enhanced ability of CD8(+) cells from LTS to suppress HIV replication.
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Barker E, Kahn J, Fujimura S, Levy JA. Protease inhibitors do not increase the CD4+ cell count in HIV-uninfected individuals. AIDS 1998; 12:1117-8. [PMID: 9662217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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