56 results on '"Bishop, G"'
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2. ICE CORE METHODS | Biological Material
- Author
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Priscu, J.C., primary, Christner, B.C., additional, Foreman, C.M., additional, and Royston-Bishop, G., additional
- Published
- 2007
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3. Assessing the environmental footprint of alternative green biorefinery protein extraction techniques from grasses and legumes.
- Author
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Gaffey J, Matinez AA, Andrade TA, Ambye-Jensen M, Bishop G, Collins MN, and Styles D
- Subjects
- Plant Proteins, Climate Change, Poaceae, Fabaceae
- Abstract
The significant grasslands of Europe and its member states represents a significant feedstock opportunity for circular bioeconomy development. The development of green biorefineries (GBR), to supply protein for the feed industry from grass, could help many European member states to address significant deficits in protein availability and reduce imports. The current study assesses the environmental footprint of alternative GBR protein extraction techniques from grasses and legumes using life cycle assessment. The focus is on comparing feedstock and technology pathways that could displace soya bean imports. The study finds that leaf protein concentrate (LPC) produced from grass had an improved environmental performance when compared to soya bean meal (SBM), across the assessed feedstock (perennial ryegrass or grass-clover mixtures) and technology pathways (one-stage maceration versus multi-stage maceration). For example, in the case of Climate Change the emission intensity for LPC was 57-85 % lower per tonne of crude protein (CP) compared with SBM. Acidification burdens were 54-88 % lower, and Eutrophication: Freshwater burdens were 74-89 % lower. Some scenarios of GBR produced LPC with a larger Energy Resources: Non-Renewable burden than SBM, though this could be mitigated with higher renewable energy (biogas and wind energy) integration within the scenario. Grass-clover scenarios generally achieved a lower intensity of emissions compared to ryegrass scenarios, particularly in the category of Climate Change, where feedstock cultivation represented a significant contributor to impacts. Overall, GBR can produce high quality protein with a lower environmental burden than SBM, but choice of feedstock and system design are critical factors for overall environmental performance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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4. Utility of CD127 combined with FOXP3 for identification of operational tolerance after liver transplantation.
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Nafady-Hego H, Li Y, Ohe H, Elgendy H, Zhao X, Sakaguchi S, Bishop GA, and Koshiba T
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- Adolescent, Adult, Cells, Cultured, Child, Female, Humans, Isoantigens immunology, Lymphocyte Culture Test, Mixed, Lymphocyte Depletion, Male, Young Adult, Biomarkers metabolism, Forkhead Transcription Factors metabolism, Graft Rejection diagnosis, Immune Tolerance, Interleukin-7 Receptor alpha Subunit metabolism, Liver Transplantation, T-Lymphocytes, Regulatory immunology
- Abstract
Loss of cell surface expression of CD127 on CD4(+)CD25(++) regulatory T-cells (Tregs) may be a useful marker to efficiently isolate Tregs. As FOXP3 was specifically used to identify Tregs, combining these two markers could give better identification for patient with operational tolerance (OT) after liver transplantation. To testify this mixed lymphocyte reaction (MLR), the function of circulating CD4(+)CD25(++)CD127(dim) cells (CD127(dim) cells) was examined in immunosuppression (IS)-free pediatric recipients after liver transplantation (LTx) (group operational tolerance: OT) (Gr-tol n=25) compared to recipients who could not stop IS due to clinically overt rejection (group intolerance) (Gr-intol n=18), recipients who were weaning IS (Gr-weaning n=11) and age-matched healthy volunteers (Gr-vol n=11). In addition, the frequencies of CD127(dim) cells vs CD4(+)CD25(++)CD127(dim)FOXP3(+) (CD127(dim)FOXP3(+)) cells were compared in these four groups by FACS analyses. Our results showed that The proliferation of CD4 cells to donor antigens was reduced compared to third-party antigens only in Gr-tol (P=0.022) but not in other groups (P=NS). Depletion of CD127(dim) cells resulted in a donor antigen-specific abrogation of this MLR hyporesponsiveness in Gr-tol (P<0.001) but not other groups (P=NS). This implied that CD127 efficiently isolated donor antigen-specific Tregs. The frequencies of CD127(dim) cells were significantly lower in Gr-intol (5.2%±1.9%) compared to those in Gr-tol (7.8%±1.8%) (P<0.001) as were the frequencies of CD127(dim) FOXP3(+) cells (Gr-tol: 5.4%±1.7% vs Gr-intol: 2.9%±1.0%, P<0.001). Of interest, there were fewer CD127(dim)FOXP3(+) cells in Gr-intol (2.9%±1%) than in Gr-weaning (5.1%±1.8%) (P=0.002), but no difference in CD127(dim) cells (Gr-intol: 5.2%±1.9% vs Gr-weaning: 6.7%±2.0%) (NS). Thus, combining FOXP3 with CD127 for phenotype analysis demonstrated an unequivocal difference between Gr-intol and Gr-weaning that was not detected by CD127 alone. In conclusion CD127 was a useful surface marker to isolate donor-antigen-specific-Tregs in OT after LTx. The additive effect of its combination with FOXP3 is important in phenotypical Treg analyses of OT patients., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
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5. Antiproliferative quillaic acid and gypsogenin saponins from Saponaria officinalis L. roots.
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Lu Y, Van D, Deibert L, Bishop G, and Balsevich J
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- Animals, Antineoplastic Agents, Phytogenic chemistry, Caryophyllaceae chemistry, Humans, Nuclear Magnetic Resonance, Biomolecular, Oleanolic Acid chemistry, Oleanolic Acid isolation & purification, Oleanolic Acid pharmacology, Plant Roots chemistry, Saponins chemistry, Sheep, Triterpenes chemistry, Antineoplastic Agents, Phytogenic isolation & purification, Antineoplastic Agents, Phytogenic pharmacology, Oleanolic Acid analogs & derivatives, Saponaria chemistry, Saponins isolation & purification, Saponins pharmacology
- Abstract
Nine quillaic acid and five gypsogenin bisdesmosides were isolated from roots of Saponaria officinalis L. (Caryophyllaceae). Seven of the quillaic acid saponins possessed a 3-O-β-D-galactopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 3)]-β-D-glucuronopyranosyl unit, but differed from each other in oligosaccharide units linked to the C-28 ester. The five gypsogenin saponins isolated from the roots all possessed the 3-O-β-D-galactopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 3)]-β-D-glucuronopyranosyl unit, with their oligosaccharide units linked to the C-28 ester differing. Structures were elucidated by extensive 1D and 2D NMR spectroscopy and mass spectrometry. The saponins were evaluated for growth inhibitory activity in two human cancer cell lines and hemolytic activity in sheep red blood cells., (Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2015
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6. Infiltrating Foxp3(+) regulatory T cells from spontaneously tolerant kidney allografts demonstrate donor-specific tolerance.
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Hu M, Wang C, Zhang GY, Saito M, Wang YM, Fernandez MA, Wang Y, Wu H, Hawthorne WJ, Jones C, O'Connell PJ, Sparwasser T, Bishop GA, Sharland AF, and Alexander SI
- Subjects
- Allografts, Animals, Cytokines metabolism, Genes, Reporter, Inflammation Mediators, Male, Mice, Mice, Inbred C3H, Mice, Inbred C57BL, Mice, Inbred DBA, Skin Transplantation, T-Lymphocytes, Regulatory metabolism, T-Lymphocytes, Regulatory pathology, Forkhead Transcription Factors physiology, Graft Rejection immunology, Graft Survival immunology, Immune Tolerance immunology, Kidney Transplantation, T-Lymphocytes, Regulatory immunology, Tissue Donors, Transplantation Tolerance immunology
- Abstract
Foxp3(+) regulatory T cells (Tregs) have an essential role in immune and allograft tolerance. However, in both kidney and liver transplantation in humans, FOXP3(+) Tregs have been associated with clinical rejection. Therefore, the role and function of graft infiltrating Tregs have been of great interest. In the studies outlined, we demonstrated that Foxp3(+) Tregs were expanded in tolerant kidney allografts and in draining lymph nodes in the DBA/2 (H-2(d) ) to C57BL/6 (H-2(b) ) mouse spontaneous kidney allograft tolerance model. Kidney allograft tolerance was abrogated after deletion of Foxp3(+) Tregs in DEpletion of REGulatory T cells (DEREG) mice. Kidney allograft infiltrating Foxp3(+) Tregs (K-Tregs) expressed elevated levels of TGF-β, IL-10, interferon gamma (IFN-γ), the transcriptional repressor B lymphocyte-induced maturation protein-1 (Blimp-1) and chemokine receptor 3 (Cxcr3). These K-Tregs had the capacity to transfer dominant tolerance and demonstrate donor alloantigen-specific tolerance to skin allografts. This study demonstrated the crucial role, potency and specificity of graft infiltrating Foxp3(+) Tregs in the maintenance of spontaneously induced kidney allograft tolerance., (© Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2013
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7. Expression of common gamma chain signalling cytokines and their receptors distinguishes rejection from tolerance in a rat organ transplant model.
- Author
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Ganbold A, Andersen S, Tay SS, Cunningham E, Ilie V, Krishnan S, Wang C, McCaughan GW, Sharland AF, and Bishop GA
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- Animals, Cytokines genetics, Cytokines immunology, Gene Expression Regulation immunology, Graft Rejection etiology, Humans, Interleukin Receptor Common gamma Subunit genetics, Interleukin Receptor Common gamma Subunit immunology, Male, Models, Animal, RNA, Messenger analysis, Rats, Rats, Inbred Strains, Receptors, Cytokine genetics, Receptors, Cytokine immunology, Receptors, Cytokine metabolism, Signal Transduction immunology, Cytokines metabolism, Graft Rejection immunology, Interleukin Receptor Common gamma Subunit metabolism, Kidney Transplantation immunology, Liver Transplantation immunology, Transplantation Tolerance immunology
- Abstract
Background: Signalling through the cytokine common γ chain (γc) is crucial for survival of activated T cells. In its absence, severe combined immunodeficiency ensues and transplanted tissues are not rejected., Methods: To determine whether differences in the availability of γc signalling cytokines correlate with rejection or acceptance, we examined expression of all γc signalling components in organs transplanted between PVG donors and DA recipients. In this combination hearts or kidneys are rejected in <10 days while livers survive >100 days. Expression of the γc cytokines IL-2, IL-4, IL-7, IL-9, IL-15 and IL-21 and their receptors γc, IL-2Rα, IL-2Rβ/IL-15Rβ, IL-4Rα, IL-7Rα, IL-9Rα, IL-15Rα and IL-21Rα was determined by real-time PCR pre-transplant and on days 3, 5 and 7 after transplantation., Results: Most increased after transplantation, although there were significantly lower levels of IL-2, IL-2Rα, IL-4 and IL-15Rα in tolerant livers compared to rejecting hearts or kidneys. IL-9 was only expressed in normal kidneys and decreased during rejection. IL-15 was constitutively expressed and did not change after transplantation. IL-21 and IL-21R increased in all transplanted organs to a similar extent. IL-7Rα in liver was considerably increased compared with heart or kidney, consistent with its known inverse relationship to global levels of γc signalling., Conclusions: In transplanted livers, acceptance is associated with low levels of all γc cytokines or receptors except IL-21. This is consistent with "dilution" of γc cytokines from a finite clone size of alloreactive T cells in livers, which are ten times larger than kidneys or hearts., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2012
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8. Tolerance in liver transplantation.
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Alex Bishop G, Bertolino PD, Bowen DG, and McCaughan GW
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- Animals, Graft Rejection immunology, Humans, Immunosuppression Therapy adverse effects, Immunosuppression Therapy methods, Liver anatomy & histology, Models, Animal, Organ Size immunology, Survival Rate, Immune Tolerance immunology, Immunosuppressive Agents administration & dosage, Liver Transplantation immunology
- Abstract
Operational tolerance (OT) in liver transplant patients occurs much more frequently than OT of other transplanted organs; however the rate of OT varies considerably with the centre and patient population. Rates of OT range from 15% of the total liver transplant (LTX) patient population down to less than 5%. This review examines the reports of liver OT and compares the factors that could contribute to this variation. Multiple factors were examined, including the time from transplantation when weaning of immunosuppression (IS) was commenced, the rapidity of weaning, the contribution of maintenance and induction IS and the patient population transplanted. The approaches that might be used to increase the likelihood of OT are discussed and the approaches to monitoring OT in LTX patients are reviewed., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
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9. Spontaneous acceptance of mouse kidney allografts is associated with increased Foxp3 expression and differences in the B and T cell compartments.
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Wang C, Cordoba S, Hu M, Bertolino P, Bowen DG, Sharland AF, Allen RD, Alexander SI, McCaughan GW, and Bishop GA
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- Animals, Apoptosis immunology, Heart Transplantation immunology, Immunoglobulins metabolism, Liver chemistry, Liver immunology, Liver metabolism, Liver Transplantation immunology, Mice, Mice, Inbred C57BL, RNA, Messenger analysis, RNA, Messenger metabolism, Rats, Skin Transplantation immunology, Transforming Growth Factor beta metabolism, B-Lymphocytes chemistry, B-Lymphocytes metabolism, Forkhead Transcription Factors genetics, Forkhead Transcription Factors immunology, Kidney Transplantation immunology, T-Lymphocytes, Regulatory chemistry, T-Lymphocytes, Regulatory metabolism, Transplantation Tolerance immunology
- Abstract
Spontaneous acceptance of organ allografts can identify novel mechanisms of drug-free transplantation tolerance. Spontaneous acceptance occurs in both mouse kidney transplants and rat liver transplants however the early immune processes of mouse kidney acceptance have not been studied. Acceptance of C57BL/6 strain kidney allografts in fully MHC-incompatible B10.BR recipients was compared with rejection (REJ) of heart allografts in the same strain combination. Graft infiltrate and antibody deposition were examined by immunohistochemical staining. Expression of mRNA was measured by quantitative real-time PCR. Apoptosis was examined by TUNEL staining. The majority of kidney allografts were accepted long-term and induced tolerance (TOL) of donor-strain skin grafts, showing that acceptance was not due to immune ignorance. There was an extensive infiltrate of T cells in the TOL kidney that exceeded the level in REJ hearts but subsequently declined. The main differences were deposition of IgG2a antibody in REJ that was absent in TOL, more B cells infiltrating TOL kidneys and a progressive increase in the ratio of CD8:CD4 cells during rejection. There was also significantly greater Foxp3 mRNA expression in TOL. Kidneys from RAG-/- donors were accepted, showing that donor lymphocytes were not necessary for acceptance. Neutralising antibodies to TGF-β administered from day 0 to day 6 did not prevent TOL. On the basis of cytokine expression and apoptosis there was no evidence for immune deviation or deletion as mechanisms of acceptance. In accord with the findings of spontaneous acceptance of liver allografts in rats, the main difference between mouse kidney TOL and heart REJ was in the B cell compartment. The major difference to rat liver allograft acceptance was that apoptosis of infiltrate did not appear to play a role. Instead, increased Foxp3 expression in TOL kidneys implies that regulatory T cells might be important., (Copyright © 2010 Elsevier B.V. All rights reserved.)
- Published
- 2011
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10. Donor IL-4-treatment induces alternatively activated liver macrophages and IDO-expressing NK cells and promotes rat liver allograft acceptance.
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Wang C, Tay SS, Tran GT, Hodgkinson SJ, Allen RD, Hall BM, McCaughan GW, Sharland AF, and Bishop GA
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- Animals, Cell Movement, Cells, Cultured, Gene Expression Profiling, Graft Rejection prevention & control, Indoleamine-Pyrrole 2,3,-Dioxygenase genetics, Indoleamine-Pyrrole 2,3,-Dioxygenase immunology, Interferon-gamma genetics, Interferon-gamma metabolism, Interleukin-2 genetics, Interleukin-2 metabolism, Killer Cells, Natural drug effects, Killer Cells, Natural immunology, Killer Cells, Natural pathology, Lectins, C-Type genetics, Lectins, C-Type immunology, Lectins, C-Type metabolism, Liver Transplantation, Macrophage Activation drug effects, Macrophages drug effects, Macrophages immunology, Macrophages pathology, Mannose Receptor, Mannose-Binding Lectins genetics, Mannose-Binding Lectins immunology, Mannose-Binding Lectins metabolism, Rats, Rats, Inbred Lew, Receptors, Cell Surface genetics, Receptors, Cell Surface immunology, Receptors, Cell Surface metabolism, Tissue Donors, Transplantation Tolerance drug effects, Transplantation Tolerance immunology, Graft Rejection immunology, Indoleamine-Pyrrole 2,3,-Dioxygenase metabolism, Interleukin-4 administration & dosage, Killer Cells, Natural metabolism, Macrophages metabolism
- Abstract
Most approaches to transplant tolerance involve treatment of the recipient to prevent rejection. This study investigates donor treatment with IL-4 for its effect on subsequent rat liver allograft survival. Rat orthotopic liver transplants were performed in rejecting (PVG donor to Lewis recipient) or spontaneously tolerant (PVG to DA) strain combinations. Donors were untreated or injected intraperitoneally with IL-4 (30,000U/day) for 5days. Tissue infiltrates and gene expression were examined by immunohistochemistry and real-time quantitative PCR. IL-4 induced a marked leukocyte infiltrate in donor livers prior to transplant. Macrophages comprised the major population, although B cells, T cells and natural killer (NK) cells also increased. IL-4-induced liver macrophages had an alternatively activated phenotype with increased expression of mannose receptor but not inducible nitric oxide synthase (NOS2). IL-4 also induced IDO and IFN-gamma expression by NK cells. Donor IL-4-treatment converted rejection to acceptance in the majority of Lewis recipients (median survival time >96days) and did not prevent acceptance in DA recipients. Acceptance in Lewis recipients was associated with increased donor cell migration to recipient spleens and increased splenic IL-2, IFN-gamma and IDO expression 24h after transplantation. Donor IL-4-treatment increased leukocytes in the donor liver including potentially immunosuppressive populations of alternatively activated macrophages and IDO-expressing NK cells. Donor treatment led to long-term acceptance of most livers in association with early immune activation in recipient lymphoid tissues., (Copyright 2009 Elsevier B.V. All rights reserved.)
- Published
- 2010
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11. The effects of neuroticism and extraversion on cardiovascular reactivity during a mental and an emotional stress task.
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Jonassaint CR, Why YP, Bishop GD, Tong EM, Diong SM, Enkelmann HC, Khader M, and Ang J
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- Adult, Anger physiology, Blood Pressure physiology, Humans, Male, Middle Aged, Neurotic Disorders physiopathology, Neurotic Disorders psychology, Stress, Psychological psychology, Young Adult, Extraversion, Psychological, Heart Rate physiology, Personality physiology, Psychomotor Performance physiology, Stress, Psychological physiopathology
- Abstract
Unlabelled: Evidence suggests that physiological reactivity to mental and emotional stress may be influenced by personality traits., Objectives: This study aimed to examine the relationship between, emotionally based personality traits, Neuroticism (N) and Extraversion (E), and cardiovascular reactivity (CVR) during mental arithmetic (MA) and anger recall (AR)., Methods: Heart rate, blood pressure, cardiac output and total peripheral resistance were measured in 114 Singaporean male patrol officers from the Singapore Police Force while they performed MA and AR tasks. N and E were assessed using the NEO PI-R., Results: Higher N was associated with lower DBP and TPRI reactivity during MA as compared to lower N, but higher TPRI reactivity during AR. Lower E scores were associated with heightened CVR while higher E scores were associated with lower CVR. For SBP and HR, E was associated with a reduction in reactivity across tasks; whereas, for DBP and TPRI this reduction was found only during AR., Conclusion: In this population, N had differential effects on CVR depending upon the nature of the stress task, cognitive or emotional. However, higher E was consistently linked to lower CVR during stress tasks and appeared to influence how individuals express and cope with anger.
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- 2009
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12. Heart allograft acceptance induced by anti-CD3 antibody in high-responder rats: effect on foxp3 and cytokine expression and graft infiltration.
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Lam VW, Taylor CF, Laurence JM, Wang C, Sharland AF, McCaughan GW, Hodgkinson S, Allen RD, Hall BM, and Bishop GA
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- Animals, Antibodies metabolism, Cytokines immunology, Forkhead Transcription Factors immunology, Rats, T-Lymphocytes immunology, T-Lymphocytes metabolism, Transplantation, Homologous, Antibodies immunology, CD3 Complex immunology, Cytokines metabolism, Forkhead Transcription Factors metabolism, Graft Survival, Heart Transplantation immunology
- Abstract
The ability of anti-T cell monoclonal antibody G4.18 and polyclonal anti-lymphocyte serum (ALS) to induce long-term graft survival was examined in a high-responder rat heart transplant model. Heterotopic heart allografts were performed from PVG rat strain donors to high-responder Lewis recipients. Immunosuppressive properties of G4.18 and ALS were investigated by immunohistochemistry and PCR analysis. Untreated graft rejection was 8.5 days while treatment with 1 ml ALS prolonged survival to 11.5 days (p=0.01). Treatment with 7 mg/kg G4.18 on days 1 and 3 prolonged survival to >100 days (p=0.002 vs. control and p=0.002 vs. ALS) but did not induce tolerance. Acceptance was associated with marked inhibition of cellular infiltration and inflammatory cytokine expression and only a brief, slight increase in Foxp3:T cell ratio in the graft and no increase in the spleen. In conclusion, G4.18 treatment led to long-term heart transplant survival associated with marked inhibition of early inflammation. Failure to develop tolerance was associated with a lack of early accumulation of Foxp3 cells in the graft or spleen.
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- 2008
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13. The axial ligand and extent of protein folding determine whether Zn or Cu binds to amicyanin.
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Ma JK, Lee S, Choi M, Bishop GR, Hosler JP, and Davidson VL
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- Bacterial Proteins metabolism, Binding Sites, Ligands, Metalloproteins metabolism, Bacterial Proteins chemistry, Copper metabolism, Metalloproteins chemistry, Protein Folding, Zinc metabolism
- Abstract
M98Q amicyanin is isolated with zinc bound to its type 1 copper-binding site. The influence of the axial ligand of the type 1 copper site on metal specificity is strongest prior to the completion of protein folding and adoption of the final type 1 site geometry. The preference for zinc over copper correlated with the selectivity of apoamicyanin in vitro in the partially folded, rather than the completely folded state. These results suggest that metal incorporation in vivo occurs during protein folding in the periplasm and not to a preformed type 1 site.
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- 2008
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14. The ligand geometry of copper determines the stability of amicyanin.
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Ma JK, Bishop GR, and Davidson VL
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- Bacterial Proteins isolation & purification, Calorimetry, Differential Scanning, Hydrogen-Ion Concentration, Ligands, Models, Molecular, Oxidation-Reduction, Protein Conformation, Spectrophotometry, Thermodynamics, Bacterial Proteins chemistry, Copper chemistry, Paracoccus denitrificans chemistry
- Abstract
Solution differential scanning calorimetry (DSC) of oxidized amicyanin, a Type I copper protein, at pH 7.5 reveals two thermal transitions. The major transition at 67.7 degrees C corresponds to the disruption of the Cys(92) thiolate to Cu(II) charge transfer as evidenced by a corresponding temperature-dependent loss of amicyanin visible absorbance. A minor transition at 75.5 degrees C describes the further irreversible protein unfolding. Reduced amicyanin exhibits a pH-dependent change of the copper ligand geometry. At pH 8.5 where the Type I tetrahedral geometry is maintained, DSC reveals two thermal transitions with T(m) values similar to that of oxidized amicyanin. At pH 6.2 where the Cu(I) coordination is trigonal planar, reduced amicyanin exhibits a single thermal transition with a lower T(m) of 64.0 degrees C. Apoamicyanin, from which copper has been removed, also exhibits a single thermal transition but with a much lower T(m) of 51.8 degrees C. Thus, the thermal stability of amicyanin is dictated both by the presence or absence of copper and its ligand geometry, but not its redox state. The physiological relevance of these data is discussed.
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- 2005
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15. Combined donor leucocyte administration and immunosuppressive drug treatment for survival of rat heart allografts.
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den Dulk M, Wang C, Li J, Clark DA, Hibberd AD, Terpstra OT, McCaughan GW, and Bishop GA
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- Adoptive Transfer, Animals, Combined Modality Therapy, Cytokines genetics, Cytokines immunology, Gene Expression, Male, Postoperative Care, RNA, Messenger biosynthesis, Rats, Rats, Inbred Strains, Skin Transplantation immunology, Tissue Donors, Transplantation, Homologous, Cyclosporine pharmacology, Graft Survival drug effects, Heart Transplantation immunology, Immunosuppressive Agents pharmacology, Indolizines pharmacology, Leukocyte Transfusion, Methotrexate pharmacology
- Abstract
Background: Donor leucocytes (DL) play an important role in rat liver transplant tolerance and their postoperative administration can convert rejection to tolerance. They appear to induce early activation, altered patterns of infiltration and death of recipient alloreactive T cells. The ability of immunosuppressive drugs to combine with DL administration was examined in a rat heart transplant model., Methods: Immediately after PVG to DA heterotopic heart transplantation, 6 x 10(7) spleen DL were injected. Cyclosporine A (CsA), 1.5 mg/kg/day, or methotrexate (MTX), 0.1 or 0.2 mg/kg/day, were given from day (d) 0 to d4 (early) or from d3 to d7 (delayed). Castanospermine (CAST) was administered from d0 to d7 at 100 or 300 mg/kg/day. In a separate experiment, transplanted hearts and recipient spleens were collected from treatment groups for analysis of infiltrate and cytokine mRNA expression., Results: Delayed treatment with CsA or early treatment with MTX but not CAST combined with DL to result in prolonged graft survival. Recipients treated with DL and delayed CsA had a reduced level of intra-graft interleukin (IL)-2, interferon (IFN)-gamma, IL-4, and IL-4R mRNA expression and reduced infiltrate compared to DL alone. Early MTX plus DL led to almost complete inhibition of all markers of inflammation during treatment followed by a rapid increase after cessation. In combination with DL, CsA was more effective than MTX for induction of donor-specific tolerance at the dose and administration regimens tested., Conclusions: Delayed CsA or early MTX combine with DL to prolong heart allograft survival. Early and extensive inhibition of rejection by MTX was less effective than delayed and partial inhibition of the response by CsA for induction of transplant tolerance.
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- 2004
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16. Time course of upregulation of fibrogenic growth factors and cellular infiltration in a rodent model of chronic renal allograft rejection.
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Pilmore HL, Yan Y, Eris JM, Hennessy A, McCaughan GW, and Bishop GA
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- Animals, Chronic Disease, Desmin analysis, Graft Rejection pathology, Histocompatibility Antigens analysis, Immunohistochemistry, Interferon-gamma genetics, Kidney physiology, Male, RNA, Messenger analysis, Rats, Rats, Inbred F344, Transforming Growth Factor beta genetics, Transplantation, Homologous, Up-Regulation, Fibroblast Growth Factor 2 genetics, Gene Expression Regulation, Graft Rejection metabolism, Kidney pathology, Kidney Transplantation immunology
- Abstract
Background: Chronic Rejection (CR) is the leading cause of renal allograft dysfunction. Upregulation of growth factors has been shown in CR but the time point at which this occurs in not known. The aim of this study was to examine the time course of upregulation of growth factors and correlate this with the macrophage and myofibroblast interstitial infiltrate., Methods: Using a rat model of CR (F344 kidney donor to Lewis recipient), infiltration by ED1 + macrophages and proliferation of alpha-smooth muscle actin (alpha-SMA) and desmin-expressing cells was examined using immunohistochemistry. In addition, expression of mRNA for interferon-gamma (IFN-gamma), transforming growth factor-beta (TGF-beta), basic-fibroblast growth factor (b-FGF) and vascular endothelial growth factor (VEGF) was studied using a semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) technique. Native Lewis rat kidney and Lewis-Lewis isografts were used as controls., Results: Immunohistochemical staining of ED1 + cells showed a marked increase in the macrophage infiltrate of allografts compared to isografts at all time periods (P = 0.0002) peaking at weeks 8-12 after transplantation. Expression of alpha-SMA was also increased in allografts (P = 0.002). RT-PCR analysis showed that mRNA for TGF-beta was maximally upregulated in allografts in comparison to isografts at week 8 after engraftment (P = 0.05) and declined thereafter, although remained at elevated levels compared to controls. IFN-gamma and b-FGF gene expression was increased in allografts late in the post-transplantation period., Conclusion: Early infiltration of macrophages and production of TGF-beta1 was followed by later upregulation of fibrogenic growth factors and myofibroblasts associated with interstitial fibrosis and organ dysfunction.
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- 2002
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17. B lymphocyte activation by contact-mediated interactions with T lymphocytes.
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Bishop GA and Hostager BS
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- Animals, B-Lymphocytes metabolism, Cell Adhesion immunology, Lymphocyte Cooperation, T-Lymphocytes metabolism, B-Lymphocytes immunology, Cell Communication immunology, Lymphocyte Activation immunology, T-Lymphocytes immunology
- Abstract
T cell dependent B lymphocyte activation requires interactions between numerous receptor-ligand pairs on the two cell types. Recently, advances have been made both in understanding how these various signals regulate B cell effector functions and in identifying many new receptor-ligand pairs that contribute to the regulation of B cell function by T lymphocytes.
- Published
- 2001
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18. Accumulation of 6-deoxocathasterone and 6-deoxocastasterone in Arabidopsis, pea and tomato is suggestive of common rate-limiting steps in brassinosteroid biosynthesis.
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Nomura T, Sato T, Bishop GJ, Kamiya Y, Takatsuto S, and Yokota T
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- Chromatography, High Pressure Liquid, Gas Chromatography-Mass Spectrometry, Kinetics, Steroids isolation & purification, Arabidopsis metabolism, Solanum lycopersicum metabolism, Pisum sativum metabolism, Steroids biosynthesis, Steroids metabolism
- Abstract
To gain a better understanding of brassinosteroid biosynthesis, the levels of brassinosteroids and sterols related to brassinolide biosynthesis in Arabidopsis, pea, and tomato plants were quantified by gas chromatography-selected ion monitoring. In these plants, the late C-6 oxidation pathway was found to be the predominant pathway in the synthesis of castasterone. Furthermore, all these plant species had similar BR profiles, suggesting the presence of common biosynthetic control mechanisms. The especially high levels of 6-deoxocathasterone and 6-deoxocastasterone may indicate that their respective conversions to 6-deoxoteasterone and castasterone are regulated in planta and hence are important rate-limiting steps in brassinosteroid biosynthesis. Other possible rate-limiting reactions, including the conversion of campestanol to 6-deoxocathasteonre. are also discussed. Tomato differs from Arabidopsis and pea in that tomato contains 28-norcastasterone as a biologically active brassinosteroid, and that its putative precursors, cholesterol and its relatives are the major sterols.
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- 2001
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19. The immune response modifier resiquimod mimics CD40-induced B cell activation.
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Bishop GA, Ramirez LM, Baccam M, Busch LK, Pederson LK, and Tomai MA
- Subjects
- Adjuvants, Immunologic pharmacology, Animals, Antibodies, Monoclonal, Apoptosis drug effects, B-Lymphocytes cytology, B-Lymphocytes metabolism, B7-1 Antigen metabolism, Cell Division drug effects, Cell Line, CpG Islands immunology, Drug Synergism, Humans, Immunoglobulin M immunology, Immunoglobulin M metabolism, Interleukin-6 metabolism, Lipopolysaccharides immunology, Mice, RNA, Messenger genetics, RNA, Messenger metabolism, Receptors, Antigen, B-Cell immunology, Tumor Necrosis Factor-alpha metabolism, Up-Regulation drug effects, B-Lymphocytes drug effects, B-Lymphocytes immunology, CD40 Antigens immunology, Imidazoles pharmacology, Immunologic Factors pharmacology, Lymphocyte Activation drug effects
- Abstract
Members of the imidazoquinoline molecule family, including imiquimod and resiquimod (R-848), have potent antiviral and antitumor activities. Imiquimod cream (5%) (Aldara) is currently indicated for treatment of external genital and perianal warts. Previous characterization of these compounds has focused upon their ability to activate monocytes and dendritic cells, but recent studies have shown that resiquimod also stimulates B lymphocytes to proliferate and express an activated phenotype. This suggests that resiquimod could potentially serve as an effective vaccine adjuvant in stimulating a humoral immune response. This study shows that resiquimod mimics effects of the T-dependent CD40 signal in both mouse and human B cell lines. Resiquimod, like CD40, stimulates antibody secretion, cytokine production, protection from apoptosis, and CD80 upregulation. In addition, it shows synergy with signals delivered by the B cell antigen receptor and heightens CD40-mediated B cell activation, demonstrating that resiquimod can enhance antigen-specific responses in B lymphocytes., (Copyright 2001 Academic Press.)
- Published
- 2001
- Full Text
- View/download PDF
20. Activation-induced programmed cell death of nonspecific cytotoxic cells and inhibition by apoptosis regulatory factors.
- Author
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Bishop GR, Jaso-Friedmann L, and Evans DL
- Subjects
- Acute-Phase Proteins physiology, Animals, Annexin A5 metabolism, Antibodies, Monoclonal pharmacology, Apoptosis drug effects, Cations, Divalent immunology, Cell Cycle immunology, Coculture Techniques, Cytotoxicity Tests, Immunologic, DNA analysis, Dexamethasone pharmacology, Female, Flow Cytometry, HL-60 Cells, Humans, Killer Cells, Natural drug effects, Killer Cells, Natural metabolism, Male, Stress, Physiological immunology, Tilapia, Apoptosis immunology, Cytotoxicity, Immunologic drug effects, Killer Cells, Natural immunology, Lymphocyte Activation drug effects
- Abstract
Nonspecific cytotoxic cells (NCC) are the teleost equivalent of mammalian lymphokine-activated natural killer cells. The cytotoxic activities of NCC are enhanced by stress-activated serum factors (SASF) present in tilapia acute-phase serum. In the present study purified NCC and xenogeneic target HL-60 tumor cells and nuclei were distinguishable in mixtures determined by flow cytometry. NCC activated by target HL-60 cells undergo activation-induced programmed cell death (AIPCD) during 12- to 16-h killing assays as shown by Annexin-V binding and nuclear DNA fragmentation results. Annexin-V binding studies also demonstrated that NCC kill HL-60 cells by an apoptotic mechanism. NCC are protected from AIPCD by 4-h preincubation in 50% SASF. Pretreatment also produced more than a fourfold increase in NCC cytotoxicity (effector/target (E:T) ratio = 100:1). In the absence of SASF preincubation, the percentage of apoptotic NCC increased from 8 to 91% at E:T ratios of 1:0 and 1:1, respectively. Kinetic studies (E:T = 10:1) demonstrated that the percentage of NCC exhibiting HL-60-dependent AIPCD increased between 0.1 and 12 h and then decreased inversely with total cell necrosis over the next 60 h. Preincubation of NCC with SASF protected NCC from AIPCD for over 72 h. Crosslinkage of the NCCRP-1 receptor with monoclonal antibody (mab) 5C6 produced AIPCD between 1 and 100 microg/mL mab concentrations. Preincubation with SASF completely protected NCC from mab 5C6-dependent AIPCD. SASF-mediated protection of NCC from AIPCD was dependent upon divalent cations, as demonstrated by increases in DNA hypoploidy of 38, 67, and 88% following preincubation in the presence of 10, 100, and 1000 microM EDTA, respectively. SASF also protected NCC from glucocorticoid- (i. e., dexamethasone) induced apoptosis. Combined, these results demonstrated that NCC activity is down-regulated by AIPCD. Release of SASF into the peripheral circulation may prevent negative regulation of NCC by AIPCD by increasing recycling capacity. Results are discussed in the context of the effects of acute stressors on innate immunity., (Copyright 2000 Academic Press.)
- Published
- 2000
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21. The site of origin of calcitonin gene-related peptide-like immunoreactive afferents to the inferior olivary complex of the mouse.
- Author
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Peltier AC and Bishop GA
- Subjects
- Animals, Brain Stem chemistry, Fluorescent Dyes, Immunohistochemistry, Injections, Intraperitoneal, Mice, Mice, Inbred C57BL, Microscopy, Fluorescence, Microspheres, Calcitonin Gene-Related Peptide analysis, Neurons, Afferent chemistry, Olivary Nucleus chemistry
- Abstract
The intent of the present study is to define the brainstem nuclei which give rise to CGRP-immunolabeled afferents to the inferior olivary complex of the mouse. A technique which combines retrograde transport of fluorescent microspheres with immunohistochemistry was used to address this question. In the present study, intensely labeled CGRP neurons were localized within several cranial nerve nuclei including the hypoglossal, facial, oculomotor, motor nucleus of the trigeminal nerve and nucleus ambiguus, as well as in the parabrachial nucleus, locus coeruleus and medullary and pontine reticular formation. In addition, lightly labeled CGRP neurons were identified within the deep cerebellar nuclei, the inferior olivary complex, lateral reticular nucleus, medial and lateral vestibular nuclei, nucleus Darkschewitsch, interstitial nucleus of Cajal, the central gray area adjacent to the third ventricle, and the zona incerta. The origin of the projection to the inferior olivary complex primarily arises from the deep cerebellar nuclei, the locus coeruleus, and the central gray matter of the mesodiencephalic area. In addition, a small CGRP input is derived from the superior and lateral vestibular nuclei as well as the zona incerta. In conclusion, we have identified several extrinsic sources of CGRP to the inferior olivary complex and have localized it within afferents that have been shown to have either excitatory (mesodiencephalic nuclei) or inhibitory (cerebellar nuclei) effects on olivary circuits. The presence of CGRP in these functionally diverse brainstem and cerebellar afferents suggests that the peptide may act as a co-transmitter to modulate the activity of olivary neurons.
- Published
- 1999
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22. Atherosclerosis of the liver allograft.
- Author
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McCaughan GW and Bishop GA
- Subjects
- Graft Rejection immunology, Humans, Liver Transplantation immunology, Microcirculation physiology, Transplantation, Homologous, Arteriosclerosis etiology, Liver Transplantation adverse effects
- Published
- 1997
- Full Text
- View/download PDF
23. T helper 1 cytokine mRNA is increased in spontaneously regressing primary melanomas.
- Author
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Lowes MA, Bishop GA, Crotty K, Barnetson RS, and Halliday GM
- Subjects
- Adult, Aged, Base Sequence, CD3 Complex analysis, CD3 Complex genetics, CD3 Complex metabolism, DNA Primers analysis, DNA Primers chemistry, DNA Primers genetics, DNA, Neoplasm analysis, DNA, Neoplasm chemistry, DNA, Neoplasm genetics, Female, Gene Expression Regulation, Neoplastic, Glyceraldehyde-3-Phosphate Dehydrogenases analysis, Glyceraldehyde-3-Phosphate Dehydrogenases genetics, Glyceraldehyde-3-Phosphate Dehydrogenases metabolism, Granulocyte-Macrophage Colony-Stimulating Factor analysis, Granulocyte-Macrophage Colony-Stimulating Factor genetics, Granulocyte-Macrophage Colony-Stimulating Factor metabolism, Growth Substances analysis, Growth Substances genetics, Growth Substances metabolism, Humans, Interferon-gamma analysis, Interferon-gamma metabolism, Interleukin-2 analysis, Interleukin-2 metabolism, Interleukins analysis, Interleukins genetics, Interleukins metabolism, Lymphotoxin-alpha analysis, Lymphotoxin-alpha metabolism, Male, Melanoma metabolism, Melanoma pathology, Middle Aged, Neoplasm Regression, Spontaneous pathology, Neoplasm Regression, Spontaneous physiopathology, RNA, Messenger genetics, RNA, Messenger metabolism, Skin chemistry, Skin metabolism, Skin pathology, Skin Neoplasms metabolism, Skin Neoplasms pathology, T-Lymphocytes chemistry, T-Lymphocytes metabolism, T-Lymphocytes pathology, Interferon-gamma genetics, Interleukin-2 genetics, Lymphotoxin-alpha genetics, Melanoma chemistry, Neoplasm Regression, Spontaneous genetics, RNA, Messenger analysis, Skin Neoplasms chemistry
- Abstract
Spontaneous tumor regression, which is observed clinically and histologically in some primary melanomas, occurs in the absence of any effective therapy. It is probably immunologically mediated, because regressing melanomas are infiltrated with larger numbers of activated T cells, primarily CD4+, than nonregressing melanomas. To investigate the hypothesis that spontaneous regression of melanomas is caused by T-cell cytokine production, cytokine mRNA expression in 20 primary melanomas was examined using a noncompetitive, quantitative reverse-transcriptase polymerase chain reaction method. DNA standards were used to generate known numbers of molecules in each sample. Results were standardized to the internal control, glyceraldehyde-3-phosphate dehydrogenase. mRNA for CD35, lymphotoxin (TNF-beta), and IL-2 were significantly elevated in the ten regressing melanomas compared to the ten nonregressing melanomas. IFN-gamma mRNA was also elevated in regressing melanomas but failed to reach statistical significance. The Th2 cytokines IL-10 and IL-13 did not show differences in the regressing melanomas compared to nonregressing melanomas; neither did the pro-inflammatory cytokines IL-1alpha, IL-1beta, IL-6, IL-8, and TNF-alpha, nor the growth factors, bFGF and TGF-beta or GM-CSF. This study shows an association between Th1 cytokines and spontaneously regressing melanomas. Although we have not shown that these cytokines cause regression, these findings support our hypothesis that activated CD4+ T cells may mediate melanoma regression by secretion of Th1 cytokines.
- Published
- 1997
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24. The distribution of corticotropin-releasing factor (CRF), CRF binding sites and CRF1 receptor mRNA in the mouse cerebellum.
- Author
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King JS, Madtes P Jr, Bishop GA, and Overbeck TL
- Subjects
- Animals, Axons metabolism, Axons ultrastructure, Cerebellum cytology, Mice, Mice, Inbred C57BL, RNA, Messenger analysis, Carrier Proteins metabolism, Cerebellum metabolism, Corticotropin-Releasing Hormone metabolism, Receptors, Corticotropin-Releasing Hormone biosynthesis
- Abstract
The purpose of the present study is to determine the distribution of CRF containing afferents, and correlate these findings with the distribution of CRF binding sites and the neuronal localization of mRNA for the CRF1 receptor in the cerebellum of a single species, the mouse. Corticotropin releasing factor (CRF) has been localized within climbing fibers and mossy fibers throughout the cerebellar cortex of the mouse using immunohistochemistry. CRF immunoreactive, axonal varicosities also are present within all four of the cerebellar nuclei. 125I-labeled CRF binding sites are evident throughout all three layers of the cerebellar cortex (molecular, Purkinje and granule cell layers), but are not seen within the cerebellar nuclei. In situ hybridization histochemistry was employed using an antisense riboprobe corresponding to the full length sequence of the rat mRNA for the CRF1 receptor. Positive signal is present throughout the cerebellum in Purkinje cells and the granule cell layer. CRF1 receptor mRNA also is expressed within all four of the cerebellar nuclei. Further experiments are required to reconcile the lack of CRF binding sites in the cerebellar nuclei with the positive mRNA receptor expression and the presence of immunoreactive axonal varicosities. In previous physiological experiments, iontophoretic application of CRF enhances spontaneous as well as quisqualate-induced activity of Purkinje cells in slice preparations of the mouse cerebellum. When the results of the anatomical techniques are compared to the physiological data, there is convergent evidence to suggest that CRF influences the firing rate or responsiveness of Purkinje cells directly via release of the peptide from the climbing fiber system and indirectly via the mossy fiber-granule cell-parallel fiber circuit. Taken together, these anatomical and physiological data provide strong evidence to suggest that, in the adult cerebellum, CRF functions as a neuromodulator.
- Published
- 1997
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25. The physiological effects of serotonin on spontaneous and amino acid-induced activation of cerebellar nuclear cells: an in vivo study in the cat.
- Author
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Kitzman PH and Bishop GA
- Subjects
- Animals, Cats, Cerebellar Nuclei drug effects, Evoked Potentials drug effects, Female, Male, Neurons drug effects, Receptors, Glutamate physiology, Serotonin physiology, Cerebellar Nuclei physiology, Excitatory Amino Acids pharmacology, Neurons physiology, Serotonin pharmacology, gamma-Aminobutyric Acid pharmacology
- Abstract
It is well established that cerebellar efferents originate from neurons located within the cerebellar nuclei. Neurons within these nuclei receive excitatory inputs derived from the axons that arise from cells in several different regions of the brainstem and spinal cord, some of which continue on to terminate as mossy fibers and climbing fibers in the cerebellar cortex. GABA-induced inhibition in the nuclei is derived primarily from Purkinje cells located in the overlying cortex and possibly from axonal collaterals of a population of small, GABAergic nuclear neurons. In addition, a third chemically defined system of afferents that contain the monoamine serotonin forms a dense plexus of fibers throughout the cat's cerebellar nuclei. The intent of this study is to determine the physiological effects of serotonin on the spontaneous activity of cerebellar nuclear cells as well as that induced by application of the excitatory amino acids glutamate and aspartate in an adult in vivo preparation. Iontophoretic application of serotonin in anesthetized preparations suppresses both spontaneous and excitatory amino acid induced activity. In addition, interactions between serotonin and the amino acid analogs quisqualate and NMDA were analyzed; 5HT suppresses the excitatory responses of neurons to both analogs. However, there is a stronger suppressive effect on quisqualate-induced excitation as compared to that elicited by NMDA. In addition to modulating the effects of the excitatory amino acids, serotonin also potentiates the inhibitory effects of GABA. However, the effect was greatest if the neuron was initially preconditioned with GABA. In summary, serotonin acts to suppress amino acid induced activity in cerebellar nuclear neurons and to enhance gABA-mediated inhibition. The net effect is a decrease in nuclear cell activity and consequently in cerebellar output.
- Published
- 1997
- Full Text
- View/download PDF
26. Cholecystokinin modulation of spontaneous and excitatory amino acid-induced activity in the opossum cerebellum.
- Author
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Bishop GA
- Subjects
- Animals, Dose-Response Relationship, Drug, Electric Conductivity, Electrodes, Opossums, Purkinje Cells drug effects, Sincalide pharmacology, Aspartic Acid pharmacology, Excitatory Amino Acid Antagonists pharmacology, Glutamic Acid pharmacology, Purkinje Cells physiology, Quisqualic Acid pharmacology, Sincalide physiology
- Abstract
Cholecystokinin-B (CCK-8) is an octapeptide that was initially described in the gastrointestinal tract. Recent studies have shown that this peptide also has an extensive distribution in the central nervous system, including the cerebellum of the opossum. In addition to the protein, binding sites for CCK-8 also have been described in the granule cell and molecular layer of this species. These anatomical data suggest that CCK-8 has a functional role in cerebellar circuitry. In the present study we have determined the physiological effects of CCK-8 on spontaneous and amino acid-induced activity. The results indicate that this peptide has both excitatory and inhibitory effects on spontaneous activity as well as the excitatory responses elicited by application of the excitatory amino acids aspartate, glutamate and quisqualate. The data suggest that CCK-8 may influence more than one population of cerebellar neurons. The findings support a neuromodulatory role for this peptide in cerebellar circuitry.
- Published
- 1996
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- View/download PDF
27. Polymorphism in the beta chain of IAq versus IAp influences presentation of protein but not peptide antigens.
- Author
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Lambert LE, Berling JS, Thompson SD, Harton JA, Bishop GA, and Choi E
- Subjects
- Amino Acid Sequence, Animals, Antigen-Presenting Cells physiology, H-2 Antigens genetics, Haplotypes, Hybridomas immunology, Mice, Molecular Sequence Data, Myelin Basic Protein metabolism, Ovalbumin metabolism, Antigen Presentation, Histocompatibility Antigens Class II genetics, Polymorphism, Genetic
- Abstract
T cells play a critical role in the development of collagen-induced arthritis (CIA). Immunization with heterologous (chick) type II collagen (cII) results in chronic inflammation with progressive damage to the joints. The expression of specific MHC Class II alpha beta dimers, including IAq, is critical to induction of disease. The alpha chains of IAq and IAp are identical in sequence. The IAq and IAp beta chains differ by only four amino acid residues: 85, 86, 88, and 89. However, mice of the H-2p haplotype are not susceptible to CIA. To examine the impact of these structural differences in IA molecules on T cell Ag recognition, we studied presentation of cII peptides and denatured cII by APCs obtained from H-2q and H-2p mice. We also assessed presentation of ovalbumin, myelin basic protein (MBP), and MBP peptides by these APC populations. H-2q APCs presented both peptides and proteins to our T cell hybrids. In contrast, APCs obtained from H-2p mice presented peptides, but were defective in the processing and/or presentation of protein Ags. We then altered pairs of the residues in IAq to those found in IAp using site-directed mutagenesis and transfected these constructs into M 12.C3 B cells. All transfectants were able to present peptides, but those expressing IAp were unable to present protein Ags. The use of transfectants expressing hybrid molecules (residues 85 and 86 from IAp, 88 and 89 from IAq, or vice versa) allowed us to localize the region responsible for this defect to residues 85 and 86 of the beta chain. The presence of IAp residues (glu and thr versus gly and val in IAq) at these sites severely compromised the capacity for protein presentation. Resistance to CIA in H-2p haplotype mice may be a reflection of the limited repertoire of epitopes to which these mice can respond relative to susceptible H-2q mice.
- Published
- 1995
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28. Calcitonin gene-related peptide modulates neuronal activity in the mammalian cerebellar cortex.
- Author
-
Bishop GA
- Subjects
- Amino Acids pharmacology, Animals, Cats, Electric Stimulation, Evoked Potentials, Glutamic Acid pharmacology, Serotonin pharmacology, Calcitonin Gene-Related Peptide pharmacology, Cerebellum physiology, Purkinje Cells physiology
- Abstract
Calcitonin gene related peptide (CGRP) has been localized within specific populations of mossy fibers in the cat's cerebellar cortex. The intent of the present study was to determine the physiological role of this peptide in cerebellar circuitry. CGRP was iontophoretically applied and its effects on spontaneous, amino acid-induced, and synaptically-mediated activity were recorded. In addition, interactions between CGRP and serotonin (5HT), another neuromodulator in cerebellar circuitry, also were analyzed. The findings of this study reveal that the primary effect of CGRP is to suppress spontaneous and excitatory amino acid-induced activity. However, CGRP has a more potent effect in suppressing aspartate- and quisqualate-induce activity as compared to that elicited by glutamate. CGRP slowed or completely blocked synaptic activity mediated by stimulation of the inferior cerebellar peduncle. Finally, the individual suppressive effects of 5HT and CGRP were potentiated when both were applied simultaneously. However, the potentiation was greater when the neuron was exposed to 5HT before CGRP was applied. In summary, the presence of CGRP in selected populations of mossy fibers, together with serotoninergic afferents, decreases the responsiveness of Purkinje cells to excitatory amino acids as well as synaptically-driven activity. Thus, activation of an afferent system to the cerebellum can elicit distinct effects on different populations of neurons that are dependent on the microenvironment of the cell at a particular point in time.
- Published
- 1995
- Full Text
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29. Problems following discharge after intensive care.
- Author
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Daffurn K, Bishop GF, Hillman KM, and Bauman A
- Subjects
- Female, Follow-Up Studies, Health Services Needs and Demand, Humans, Male, Middle Aged, Critical Care, Health Status, Patient Discharge, Quality of Life
- Abstract
Intensive care units (ICUs) are now present in most acute care hospitals. While long-term studies on patients admitted to these units have been performed to identify mortality, functional outcome and quality of life, there is little information on the recovery period in the weeks immediately following discharge. The aim of this study was to identify and describe the sequelae found in patients at 3 months after leaving the ICU. The study was conducted over a 6-month period during 1991, in a university teaching hospital in Sydney, Australia. 54 patients with a length stay (LOS) of greater than 48 hours in the ICU were included. Each patient was interviewed in an outpatient clinic attached to the ICU. Information collected included pre-admission details, reason for admission, treatments provided and complications encountered. General health state, social and employment details, functional status, referral patterns since discharge and recollection of ICU stay were studied. The major findings indicated that many of the patients interviewed were returning towards near normal general health, but were suffering mild to moderate physical and psychosocial sequelae. In the majority of cases the problems were not incapacitating. The predominant complaints were minor to severe pain, sleeping difficulties, tiredness and breathlessness. Financial problems were reported by a small number of patients. Depression, irritability or a feeling of loneliness were present in over one-third of the group. More than half the patients required referral for further assessment. 34% of patients had no recollection of their ICU stay. 16 patients (29.6%) reported unpleasant memories including nightmares and hallucinations.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1994
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30. Do nurses know when to summon emergency assistance?
- Author
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Daffurn K, Lee A, Hillman KM, Bishop GF, and Bauman A
- Subjects
- Adolescent, Adult, Aged, Child, Communication, Female, Humans, Male, Middle Aged, Nursing Assessment, Surveys and Questionnaires, Emergencies nursing, Heart Arrest nursing, Heart Arrest prevention & control, Patient Care Team
- Abstract
At Liverpool Hospital in 1989, mortality from cardiopulmonary arrest was 71% in the general wards, and 64% in the Emergency department. In an attempt to identify and treat seriously ill patients before they progressed to cardiac arrest, a medical emergency team (MET) was established. The MET replaced the existing cardiac arrest team and comprised a nurse from the intensive care unit (ICU), a resuscitation registrar (an anaesthetics trainee), a medical registrar and a senior registrar from the ICU. The resuscitation registrar was the team leader. The calling criteria for the MET were based on predetermined physiological variables, abnormal laboratory results, and specific conditions or if nursing or medical staff were concerned by the patient's condition. A study was conducted 2 years following implementation of the MET system, to determine registered nurses' (RNs) opinions, knowledge and use of the system. A questionnaire distributed to 141 nurses rostered on the chosen study date revealed a positive attitude the MET, although there was a low awareness regarding the availability of the MET information booklet. 53% of nurses had called the MET in the last 3 months; all would call the team again in the same circumstances. The correct response in three of four hypothetical situations presented was to call the MET. The number of correct responses varied between scenarios from 17-73%. Hypotension did not appear to alert nurses to summon emergency assistance. Some nurses, despite the presence of severe deterioration and patient distress, called the resident rather than the MET.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1994
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31. Extravascular fluid uptake during cardiopulmonary bypass in hypertensive dogs.
- Author
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Wolfer RS, Bishop GG, Burdett MG, Shigemi K, Freeman JP, Krasna MJ, McLaughlin JS, and Brunner MJ
- Subjects
- Animals, Blood Pressure, Carotid Sinus physiology, Dogs, Male, Body Fluid Compartments physiology, Cardiopulmonary Bypass, Central Venous Pressure physiology, Hypertension, Renovascular physiopathology, Hypertension, Renovascular surgery, Pressoreceptors physiology, Vasodilation physiology, Water-Electrolyte Balance physiology
- Abstract
We investigated the effects of increases in central venous pressure (CVP) and carotid baroreceptor-induced vasodilation on the rate of extravascular fluid uptake during cardiopulmonary bypass in normotensive and Goldblatt hypertensive dogs. Carotid sinus baroreceptors were selectively perfused to control the level of vasodilation. Central venous pressure was controlled by changing the height of the venous outflow cannula. Extravascular fluid uptake was determined from the rate of change in reservoir volume. After 3 hours of bypass, total fluid accumulation was 56.11 +/- 14.16 mL/kg in normotensive dogs, significantly less than in hypertensive dogs (110.90 +/- 23.20 mL/kg) (p < 0.05). Raising CVP from 1 to 5 mm Hg increased the rate of extravascular fluid uptake in both normotensive (from 0.05 +/- 0.25 to 0.85 +/- 0.22 mL.kg-1.min-1; p < 0.05) and hypertensive dogs (from 0.68 +/- 0.28 to 2.57 +/- 0.46 mL.kg-1.min-1; p < 0.01)). At a constant CVP, baroreceptor-induced vasodilation increased the rate of extravascular fluid uptake in normotensive (from 0.25 +/- .15 to 0.81 +/- .22 mL.kg-1.min-1) and in hypertensive dogs (from 0.84 +/- .12 to 1.72 +/- .32 mL.kg-1.min-1; p < 0.05). Hypertensive dogs were more sensitive to changes in CVP and to baroreceptor-induced vasodilation. The results of this study imply that elevations in CVP or the use of vasodilators may lead to increased extravascular fluid uptake during bypass; this effect may be exacerbated in the hypertensive state.
- Published
- 1994
- Full Text
- View/download PDF
32. False detection of negative-strand hepatitis C virus RNA.
- Author
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McGuinness PH, Bishop GA, McCaughan GW, Trowbridge R, and Gowans EJ
- Subjects
- False Positive Reactions, Hepatitis C blood, Humans, Reproducibility of Results, Hepacivirus genetics, Hepatitis C diagnosis, Liver microbiology, Polymerase Chain Reaction methods, RNA, Viral analysis, RNA-Directed DNA Polymerase
- Published
- 1994
33. Intragraft cytokine mRNA levels in human liver allograft rejection analysed by reverse transcription and semiquantitative polymerase chain reaction amplification.
- Author
-
Bishop GA, Rokahr KL, Napoli J, and McCaughan GW
- Subjects
- Acute Disease, Adolescent, Adult, Aged, Base Sequence, Child, Preschool, Chronic Disease, Cytokines genetics, Female, Humans, Interferon-gamma biosynthesis, Interferon-gamma genetics, Interleukin-1 biosynthesis, Interleukin-1 genetics, Interleukin-10 biosynthesis, Interleukin-10 genetics, Interleukin-6 biosynthesis, Interleukin-6 genetics, Liver metabolism, Male, Middle Aged, Molecular Sequence Data, Polymerase Chain Reaction, RNA, Messenger genetics, RNA-Directed DNA Polymerase, Cytokines biosynthesis, Gene Expression Regulation, Graft Rejection genetics, RNA, Messenger analysis
- Abstract
Cytokine gene expression was analysed by reverse transcriptase-polymerase chain reaction (RT-PCR) amplification of RNA from 27 human liver allograft specimens diagnosed as acute (n = 19) or chronic (n = 8) rejection and from 12 normal human livers. In initial screening experiments, mRNA for cytokines interleukin (IL)-1 beta, IL-6, IL-10 and gamma-interferon (IFN-gamma) was expressed in all normal livers and almost all allograft specimens tested. IL-2 mRNA was expressed at barely detectable levels in four of 12 normal livers screened and in 20 of 26 liver allograft specimens with rejection. This constitutive expression of cytokine mRNA required semiquantitative PCR analysis to differentiate levels of cytokine mRNA expression between specimens. Titration of cDNA prior to PCR amplification was initially used and showed significantly more IL-2 (p = 0.02) and IFN-gamma (p = 0.03) in acute rejection compared to normal liver. There was also significantly less IL-10 in chronic rejection compared to acute rejection (p = 0.02) or normal liver (p = 0.01) and less IL-6 in acute rejection compared to chronically rejecting liver (p = 0.05). IL-1 beta (p = 0.04) and IL-6 (p = 0.01) were reduced in acute rejection compared to normal liver. The slight increase of IL-2 in acute rejection and the slight decrease of IL-10 in chronic rejection was confirmed by a second semiquantitative analysis which involved removal of aliquots of PCR reaction at successive cycles followed by dot-blotting and hybridization.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
- Full Text
- View/download PDF
34. Differential modulation of Purkinje cell activity by enkephalin and corticotropin releasing factor.
- Author
-
Bishop GA and King JS
- Subjects
- Action Potentials drug effects, Animals, Aspartic Acid pharmacology, Corticotropin-Releasing Hormone analysis, Corticotropin-Releasing Hormone physiology, Enkephalins analysis, Enkephalins physiology, Glutamates pharmacology, Glutamic Acid, Iontophoresis, Opossums, Purkinje Cells chemistry, Second Messenger Systems, Corticotropin-Releasing Hormone pharmacology, Enkephalins pharmacology, Purkinje Cells drug effects
- Abstract
Several peptides have been localized within afferents to the opossum's cerebellum, including cholecystokinin (15), enkephalin (16, 17) and corticotropin releasing factor (7, 9). Each of these peptides has a heterogeneous laminar and lobular distribution. Two peptide, enkephalin (ENK) and corticotropin releasing factor (CRF) are present in specific populations of climbing fibers and mossy fibers, which have an overlapping distribution in several areas of the cerebellum, in particular the lateral aspect of vermal lobules VII and VIII. Within this location ENK and CRF are co-localized in individual climbing fibers and mossy fibers (7). In the present study, the physiological effects of these peptides on Purkinje cell activity were analyzed. The data indicate that ENK and CRF have opposite effects on Purkinje cell activity. ENK suppresses spontaneous activity as well as that induced by application of glutamate and aspartate, as described previously (5). In contrast, CRF enhances both spontaneous and amino acid-induced unit activity. Further, when applied simultaneously, CRF blocks the suppressive effect induced by ENK. Previous studies have shown that climbing fibers, as well as the mossy fiber-parallel fiber pathway, are excitatory to Purkinje cells (11). However, immunohistochemical data have shown that these afferents are heterogeneous with respect to their chemical content (7-9, 15-17, 25). As found in the current and previous studies (3, 5) peptides in climbing and mossy fibers modulate the responsiveness of Purkinje cells to primary excitatory neurotransmitters in selected areas of the cerebellar cortex. However, the firing rate of individual Purkinje cells is differentially altered depending on which neurochemical messenger(s) are released.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1992
- Full Text
- View/download PDF
35. Lymphocyte adhesion molecules in T cell-mediated lysis of human kidney cells.
- Author
-
Suranyi MG, Bishop GA, Clayberger C, Krensky AM, Leenaerts P, Aversa G, and Hall BM
- Subjects
- Antibodies, Monoclonal immunology, CD58 Antigens, Cells, Cultured, Cytotoxicity Tests, Immunologic, Fluorescent Antibody Technique, Graft Rejection immunology, Histocompatibility Antigens Class I immunology, Histocompatibility Antigens Class II immunology, Humans, Kidney Transplantation immunology, Antigens, Surface immunology, Kidney immunology, Lymphocyte Function-Associated Antigen-1 immunology, Membrane Glycoproteins immunology, T-Lymphocytes, Cytotoxic immunology
- Abstract
The complementary adhesion molecules LFA-1 (CD11a, 18)/ICAM-1 (CD54) and LFA-2 (CD2)/LFA-3 (CD58) have been shown to be important in T cell interaction with lymphoid target cells. The role of these ligand pairs in cytotoxicity against somatic cells is less well established. While LFA-3 is expressed by all cells in the kidney, ICAM-1 expression is low in normal kidneys but is increased in allograft rejection. An in vitro cytotoxicity assay was used to examine the relative importance of the two adhesion ligands in immune damage against kidney cells in rejection. HLA-A2 specific cytotoxic T lymphocyte (CTL) recognition of cultured human kidney cells (HKC), of predominantly renal tubular cell origin, was studied. Immunofluorescence studies showed that both induced and uninduced HKC target cells expressed ICAM-1, MHC class I and LFA-3, but only MHC class I and class II antigens and ICAM-1 were significantly upregulated by cytokine induction. Effector cells expressed LFA-1 and LFA-2 but little or no ICAM-1 and LFA-3. Cytokine induction of ICAM-1 expression on HKC target cells increased their susceptibility to lysis. Monoclonal antibody against ICAM-1 or LFA-1 produced the greatest inhibition of HKC lysis, and their effects were not additive. Antibody against LFA-2 (CD2) or LFA-3 also produced significant inhibition, but to a lesser degree, and no additive effect was found.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1991
- Full Text
- View/download PDF
36. Cyclosporine inhibition of CH series murine B-cell lymphomas.
- Author
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Gorelick MH, Bishop GA, Haughton G, and Pisetsky DS
- Subjects
- Animals, Antigens, Surface analysis, B-Lymphocytes cytology, B-Lymphocytes immunology, Cell Division drug effects, Cell Line, Dose-Response Relationship, Drug, HeLa Cells, Humans, Lipopolysaccharides pharmacology, Mice, B-Lymphocytes drug effects, Cyclosporins pharmacology, Lymphoma physiopathology
- Abstract
To investigate the mechanisms by which cyclosporine (CsA) inhibits B-cell function, the effect of this agent on murine B-lymphoma cell lines of the CH series was tested. These lymphomas appear to be derived from a restricted B-cell population on the basis of their common expression of the Ly-1 cell surface marker and autoantibody products. Proliferation of each of the six cell lines tested was inhibited by CsA at doses without effect on the nonlymphoid HeLa cell line. The cell lines, however, differed from each other in their sensitivity to this agent. To correlate this sensitivity to other functional B-cell properties, the effect of lipopolysaccharide (LPS) on the proliferation of the CH cell lines was tested. Three of the lines showed enhanced proliferation to LPS; two were inhibited while one was unaffected. The cell lines that responded with increased proliferation to LPS were the most sensitive to CsA. These results indicate that sensitivity to CsA may be a common property of B cells of certain lineages, although the degree of sensitivity may be influenced by the activation properties of these cells.
- Published
- 1987
- Full Text
- View/download PDF
37. Expression of leucocyte and lymphocyte adhesion molecules in the human kidney.
- Author
-
Bishop GA and Hall BM
- Subjects
- Antigens, CD analysis, CD58 Antigens, Humans, Immunoenzyme Techniques, Killer Cells, Natural metabolism, Leukocytes, Mononuclear metabolism, Lymphocyte Function-Associated Antigen-1, Macrophages metabolism, T-Lymphocytes metabolism, Antigens, Differentiation metabolism, Antigens, Surface metabolism, Graft Rejection immunology, Kidney metabolism, Kidney Transplantation immunology, Membrane Glycoproteins metabolism, Receptors, Leukocyte-Adhesion metabolism
- Abstract
Leucocyte interaction with other cells is facilitated by the adhesion molecules, leucocyte function-associated antigen-1 (LFA-1)-binding to intercellular adhesion molecule-1 (ICAM-1) and for T cells and natural killer (NK) cells the binding of LFA-2 (CD2) to LFA-3. As these interactions are critical for the mediation of graft destruction by effector T cells, we examined whether there was a change in the expression of these molecules during rejection compared to normal kidneys. In normal kidneys, peritubular and glomerular capillaries and large vessel endothelium expressed ICAM-1 and LFA-3, but tubular cells expressed only low levels of LFA-3. LFA-1-expressing cells, which were probably macrophages, were observed in the glomerulus. A few scattered LFA-1-expressing cells in the interstitium were probably tissue macrophages or dendritic cells, and only occasional interstitial mononuclear cells expressed LFA-2. During rejection, there was an infiltrate of mononuclear cells expressing LFA-1 and the T cell and NK cell component of the infiltrate expressed LFA-2. Neither of these markers was expressed by kidney parenchymal cells except for one allograft with severe rejection which showed LFA-1 beta chain expression by some tubular cells. Tubular cells had increased expression of ICAM-1 during rejection but there was no increase in LFA-3. The importance of LFA-2 and ICAM-1 expression on kidney tubular cells for adhesion of activated T cells was also examined in an in vitro system.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1989
- Full Text
- View/download PDF
38. Increased expression of HLA-DR antigens on renal tubular cells in renal transplants: relevance to the rejection response.
- Author
-
Hall BM, Bishop GA, Duggin GG, Horvath JS, Philips J, and Tiller DJ
- Subjects
- Adult, Cadaver, Female, HLA-DR Antigens, Histocompatibility, Humans, Immunoenzyme Techniques, Kidney pathology, Male, Middle Aged, Transplantation Immunology, Graft Rejection, Histocompatibility Antigens Class II analysis, Kidney Transplantation, Kidney Tubules immunology
- Abstract
Whether the expression of DR antigens is altered in cadaver renal transplants was examined by the use of monoclonal antibodies to the non-polymorphic region of the DR molecule and an indirect immunoperoxidase stain. Expression of DR antigens increased considerably on renal tubular cells in all 25 biopsy specimens which showed severe cellular rejection, but in only 4 of 14 biopsy specimens with no or minimum evidence of rejection. 2 of these 4 specimens were from patients recently treated for severe rejection and the other 2 subsequently lost their grafts from chronic rejection. DR antigens were also expressed on the cell surface of isolated tubular cells aspirated from transplanted kidneys with acute cellular rejection but not on tubular cells in normal kidneys or aspirates from kidneys without rejection. Biopsy specimens with increased DR expression in tubules usually had an interstitial T cell infiltrate. Expression of DR antigens on tubular cells was not related to HLA-DR incompatibility between donor and host, or to the type of immunosuppressive therapy given. The expression of DR antigens on renal tubular cells may be induced by the infiltrating activated T cells or be a consequence of tubular regeneration following rejection or ischaemic damage. The increased expression of DR antigens on renal tubular cells during rejection makes these cells potential targets for delayed type hypersensitivity responses, which are only effective against DR antigen bearing cells.
- Published
- 1984
- Full Text
- View/download PDF
39. Immunopathology of renal allograft rejection analyzed with monoclonal antibodies to mononuclear cell markers.
- Author
-
Bishop GA, Hall BM, Duggin GG, Horvath JS, Sheil AG, and Tiller DJ
- Subjects
- B-Lymphocytes immunology, Biopsy, HLA Antigens immunology, HLA-DR Antigens, Histocompatibility Antigens Class II immunology, Humans, Immunoenzyme Techniques, Immunosuppressive Agents therapeutic use, Kidney immunology, Kidney pathology, Lymphocyte Activation, Nephrectomy, T-Lymphocytes, Cytotoxic immunology, T-Lymphocytes, Helper-Inducer immunology, Time Factors, Antibodies, Monoclonal immunology, Antigens, Surface immunology, Graft Rejection drug effects, Kidney Transplantation, Monocytes immunology
- Abstract
The composition of the mononuclear cell infiltrate in rejecting renal allografts was determined on 96 renal biopsies and 22 nephrectomy specimens by the use of monoclonal antibodies to mononuclear cell surface markers and an indirect immunoperoxidase staining technique. During rejection the composition of the infiltrate was heterogeneous, with T cells (T11), monocytes (OKM1) and HLA-DR expressing mononuclear cells the most frequent sub-populations. B cells (B1) and activated T cells, identified by OKT10, were always in the minority. The T cells infiltrate usually included the helper/inducer (T4) and cytotoxic (T8) subclasses, which suggests that both may contribute to the mediation of rejection. Whether T4 or T8 predominated in the graft did not relate to the ratio of T4:T8 in blood, the HLA A, B or DR incompatibilities of the graft, or the immunosuppressive used. The frequency of T11, T4, T8, HLA-DR positive cells and monocytes, but not B cells, increased with the severity of rejection and was similar in biopsies from patients immunosuppressed with Cyclosporine (CSA) to those given a combination of azathioprine, prednisone and antilymphocyte globulin (AZA). Severe rejection episodes which did not respond to treatment with corticosteroids were more often characterized by a predominance of T8 over T4 cells and T cells infiltrating the glomeruli. In grafts with evidence of cellular rejection, renal tubular cells were shown to have a marked increase in their expression of HLA-DR antigens compared to normal kidneys or grafts with minimal rejection. The expression of HLA-DR antigens on graft tubular cells correlated with the presence of T cells in the interstitium and the severity of rejection, except for moderate rejection in CSA treated biopsies, in which HLA-DR expression was lower than in AZA biopsies. These immunopathological studies have demonstrated that a variety of potential effector cells exist within the graft, and several features have been identified which may assist in assessing the prognosis of the rejection episode.
- Published
- 1986
- Full Text
- View/download PDF
40. The male midwife, back in 1779.
- Author
-
Bishop GH
- Subjects
- England, History, 16th Century, History, 17th Century, History, 18th Century, Humans, Male, Midwifery history
- Published
- 1977
41. High-performance liquid chromatographic determination of benzbromarone and the main metabolite benzarone in serum.
- Author
-
Vergin H and Bishop G
- Subjects
- Benzbromarone analogs & derivatives, Chromatography, High Pressure Liquid methods, Half-Life, Humans, Kinetics, Benzbromarone blood, Benzofurans blood
- Published
- 1980
- Full Text
- View/download PDF
42. A differential scanning calorimeter for ice nucleation distribution studies--application to bacterial nucleators.
- Author
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Parody-Morreale A, Bishop G, Fall R, and Gill SJ
- Subjects
- Calorimetry, Differential Scanning instrumentation, Cloning, Molecular, Escherichia coli genetics, Genes, Bacterial, Models, Theoretical, Freezing
- Abstract
A differential scanning calorimeter has been developed for the automatic detection and measurement of dropwise freezing within a sample of 100-200 water drops. A typical drop size of 1 microliter is employed. The sample is distributed on flat, square (4-cm) thermoelectric sensors and the temperature is scanned downward by conductive cooling to a liquid nitrogen bath. The rate of cooling, typically 1 degree C/min, is set by the choice of a heat conduction rod between the calorimeter and the liquid nitrogen bath. The voltages from the thermopiles along with a system temperature-measuring thermocouple are continuously monitored by digital voltmeters and recorded every half-second in a computer memory. A freezing event in a drop is detected by a characteristic voltage signal whose integral with time is proportional to the size of the drop and its heat of fusion. The half-life of a freezing event signal is 10 s for a 1-microliter drop. The integrated signal produced from multiple freezing events is shown to provide a direct measure of the number of drops frozen at a given temperature. A distribution curve and its smoothed derivative can be constructed directly from these measurements. The instrument, which is termed an "ice nucleometer," is illustrated in determining the ice nucleation distribution in a population of Escherichia coli harboring cloned ice nucleation genes.
- Published
- 1986
- Full Text
- View/download PDF
43. Diagnosis of renal allograft rejection by analysis of fine-needle aspiration biopsy specimens with immunostains and simple cytology.
- Author
-
Bishop GA, Hall BM, Waugh J, Philips J, Horvath JS, Duggin GG, Johnson JR, Sheil AG, and Tiller DJ
- Subjects
- Antibodies, Monoclonal, Azathioprine therapeutic use, Biopsy, Needle, Creatinine blood, Cyclosporins therapeutic use, HLA-DR Antigens analysis, Histocytochemistry, Humans, Immunoenzyme Techniques, T-Lymphocytes immunology, Graft Rejection, Kidney Transplantation
- Abstract
Fine-needle aspiration biopsy specimens of renal transplants were analysed by means of commercially available monoclonal antibodies and an immunoperoxidase stain. Three cellular features associated with acute cellular rejection were identified--heavy infiltrates of activated T cells or large mononuclear cells strongly expressing HLA-DR antigens, and HLA-DR expression by renal tubular cells. A combination of semiquantitative scores for these features correctly identified rejection in 32 of 34 cases, with no false positives in cases of cyclosporin nephrotoxicity or stable graft function.
- Published
- 1986
- Full Text
- View/download PDF
44. Properties of dendrites; apical dendrites of the cat cortex.
- Author
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CLARE MH and BISHOP GH
- Subjects
- Animals, Cats, Cerebral Cortex physiology, Dendrites, Electricity, Felis, Neurons
- Published
- 1955
- Full Text
- View/download PDF
45. The cortical response to direct stimulation of the corpus callosum in the cat.
- Author
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CLARE MH, LANDAU WM, and BISHOP GH
- Subjects
- Animals, Cats, Basal Ganglia physiology, Corpus Callosum, Electroencephalography, Felis, Ganglia
- Published
- 1961
- Full Text
- View/download PDF
46. Relations between specifically evoked and spontaneous activity of optic cortex.
- Author
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BISHOP GH and CLARE MH
- Subjects
- Cerebral Cortex physiology, Eye, Nervous System Physiological Phenomena
- Published
- 1952
- Full Text
- View/download PDF
47. Potential phenomena in thalamus and cortex.
- Author
-
Bishop GH
- Subjects
- Axons, Brain, Cerebral Cortex physiology, Electric Stimulation, Evoked Potentials, Thalamus physiology
- Abstract
1. The cortical response to stimulation of an afferent path consists of two parts, a specific response indicating projection of the afferent and a response of the alpha mechanism. The former of these under the influence of strychnine can be identified with the cortical spikes of paroxysmal activity. 2. The response of the geniculate and other simply arranged nuclei are monophasic spikes. The diphasic spikes of the cortex and elsewhere are inferred to be assignable to two different groups of cells related by synaptic passage. 3. The unit cell potential may be interpreted as the resultant of unequal depolarization during activity of the two ends of the cell dendritic and axonal. If this is so, polarization by external currents should modify or even reverse the potentials and this proves to be the case. The phenomena are comparable to the effects of polarization on nerve axons. 4. Three types of potential fields can be visualized of which different cell structures of the brain may be considered as variants. Plots of the potentials of these fields indicate what relation of potential form to structure may be expected to obtain. 5. The character of the relation between thalamus and cortex appears to be different for the specific response apparatus which is not spontaneously active expect in paroxysmal states and the regulatory apparatus which is normally spontaneously active but suppressed in paroxysm. It is not necessary to infer reverberating closed circuits to account for the activity in either system.
- Published
- 1949
48. The interactions of several varieties of evoked response in visual and association cortex of the cat.
- Author
-
LANDAU WM, BISHOP GH, and CLARE MH
- Subjects
- Animals, Cats, Cerebral Cortex physiology, Electroencephalography, Felis, Optic Nerve physiology, Thalamus physiology
- Published
- 1961
- Full Text
- View/download PDF
49. Potential wave mechanisms in cat cortex.
- Author
-
BISHOP GH and CLARE MH
- Subjects
- Animals, Cats, Cerebral Cortex physiology, Electroencephalography, Felis, Radiation, Nonionizing
- Published
- 1956
- Full Text
- View/download PDF
50. The skin as an organ of senses with special reference to the itching sensation.
- Author
-
BISHOP GH
- Subjects
- Humans, Pruritus, Sensation, Skin
- Published
- 1948
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