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91.
Upward or downward shifts in the level of brain GABAergictransmission have been held to be necessary and sufficient to promote release of endogenous ligands ('endocoids') for the benzodiazepine (BZD) recognition site. To investigate this possibility, variable-interval self-stimulation performance was used to monitor 'intrinsic' benzodiazepine-like and anti- benzodiazepine activity by the 'neutral' benzodiazepine-receptor antagonist, Ro 15-1788 (flumazenil) (10 or 30 mg/kg intraperitoneally). Rats were pretreated with either a GABA synthesis blocking agent (isoniazid, 130 mg/kg subcutaneously), or with a GABA agonist (progabide, 30 or 100 mg/kg intraperitoneally). The lower dose of Ro 15-1788 (10 mg/kg), without pretreatment, did not affect self-stimulation; higher doses (30 mg/kg) caused a brief (<20 min) depression. Isoniazid (130 mg/kg) depressed self-stimulation, but did not modify the activity of Ro 15-1788. In rats pretreated with progabide (100 mg/kg), low doses of Ro 15- 1788 (10 mg/kg) that were previously without effect now caused a sharp fall in responding. These findings can be interpreted as showing that even low doses of Ro 15-1788 may affect self-stimulation under certain conditions, and that they do so by competing with an endogenous ligand for the benzodiazepine site, released by upward shifts in GABAergic activity. Alternative explanations in terms of altered receptor function seem less feasible. The results imply that the action of the endogenous ligand would not resemble that of a typical benzodiazepine, but that of an inverse agonist (that is, proconflict and proconvulsant); this conclusion agrees with recent biochemical evidence. 相似文献
92.
Blood platelet uptake of serotonin in episodic aggression 总被引:2,自引:0,他引:2
C S Brown T A Kent S G Bryant R M Gevedon J L Campbell A R Felthous E S Barratt R M Rose 《Psychiatry research》1989,27(1):5-12
Blood platelet uptake of 3H-serotonin (5HT uptake), a potential marker of serotonergic function, was determined in male outpatients with episodic aggression (n = 15) and in age- and sex-matched nonaggressive controls (n = 15). Correlations with rating scales of "impulsivity" (Barratt Impulsivity Scale, 10th revision) and "anger" (Spielberger Anger Expression Scale) were performed. Mean 5HT uptake was 18% lower in patients with episodic aggression. A significant negative correlation between % difference in platelet 5HT uptake and impulsivity score was observed, but the correlation between 5HT uptake and anger was not significant. These results support the hypothesis of disturbed serotonergic function in aggression and suggest that the primary relationship is in the "control" of aggression. The blood platelet may be useful in identifying impulsive subtypes. 相似文献
93.
M. Elaine Rose 《Immunology》1961,4(4):346-353
Antibodies to Eimeria stiedae were measured in rabbit serum by complement fixation. The titre rose to a maximum at about the 22nd day after infection, remained at this level for about 20 days and then declined. Antibodies were still detectable up to 160 days after infection.
Evidence of past or present slight E. stiedae infection was found in clinically normal rabbits whose sera fixed complement with E. stiedae antigens.
Challenge of rabbits which had recovered from a near-fatal infection had no effect upon the complement fixation titres of their sera.
The serum of a rabbit which had been injected with alum-precipitated antigen fixed complement with E. stiedae antigens. However, the animal was still susceptible to a superimposed oral infection which had the effect of further increasing the serum titre.
相似文献94.
Pediatric solid-organ transplant recipients carry chronic loads of Epstein-Barr virus exclusively in the immunoglobulin D-negative B-cell compartment
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Rose C Green M Webber S Ellis D Reyes J Rowe D 《Journal of clinical microbiology》2001,39(4):1407-1415
Solid-organ transplant recipients are at risk for development of lymphoproliferative diseases. The purpose of this study was to examine the distribution of Epstein-Barr virus (EBV) load in the peripheral blood of pediatric transplant recipients who had become chronic viral load carriers (>8 copies/10(5) lymphocytes for >2 months). A total of 19 patients with viral loads ranging from 20 to 5,000 viral genome copies/10(5) lymphocytes were studied. Ten patients had no previous diagnosis of posttransplant lymphoproliferative disease (PT-LPD), while nine had recovered from a diagnosed case of PT-LPD. No portion of the peripheral blood viral load was detected in the cell-free plasma fraction. Viral DNA was found in a population of cells characterized as CD19(hi) and immunoglobulin D negative, a phenotype that is consistent with the virus being carried exclusively in the memory B-cell compartment of the peripheral blood. There was no difference in the compartmentalization based upon either the level of the viral load or the past diagnosis of an episode of PT-LPD. These results have implications for the design of tests to detect EBV infection and for the interpretation and use of positive EBV PCR assays in the management of transplant recipients. 相似文献
95.
96.
T-Cell Regulation in Autoimmune Thyroiditis 总被引:12,自引:0,他引:12
Nohl R. Rose YI-CHI M. KONG Isao Okayasu Alvaro A. Giraldo Kirk Beisel Roy S. Sundick 《Immunological reviews》1981,55(1):299-314
97.
98.
Competitive control of the self-renewing T cell repertoire 总被引:1,自引:0,他引:1
We develop a mathematical model for the self-renewing part of the T cell
repertoire. Assuming that self-renewing T cells have to be stimulated by
immunogenic MHC-peptide complexes presented on the surfaces of
antigen-presenting cells, we derive a model of T cell growth in which
competition for MHC-peptide complexes limits T cell clone sizes and
regulates the total number of self-renewing T cells in the animal. We show
that for a sufficient diversity and/or degree of cross-reactivity, the
total T cell number hardly depends upon the diversity of the T cell
repertoire or the diversity of the set of presented peptides. Conversely,
for repertoires of lower diversity and/or cross-reactivity, steady-state
total T cell numbers may be limited by the diversity of the T cells. This
provides a possible explanation for the limited repertoire expansion in
some, but not all, mouse T cell re-constitution experiments. We suggest
that the competitive interactions described by our model underlie the
normal T cells numbers observed in transgenic mice, germ-free mice and
various knockout mice.
相似文献
99.
Elaine Reed Eric Ho David J. Cohen William Ramey Charles Marboe Vivette D'Agati Eric A. Rose Mark Hardy Nicole Suciu-Foca 《Immunologic research》1993,12(1):1-11
Chronic rejection is the major threat to both heart and renal allograft survival. We have explored the possibility that some
patients with anti-donor HLA antibodies (Ab1) develop specific anti-idiotypic antibodies (Ab2) which suppress the production
of Ab1, and subsequently, the progression of chronic rejection. analysis of Ab2 in sera obtained from Ab1 producers showed
that 22% of heart and 18% of kidney recipients produced Ab2. The 4- and 5-year actuarial graft survivals in Ab2 producers
were 100% and 83%, respectively, compared to 57% in patients who formed Ab1 but not Ab2 (p<0.004). Patients carrying the DR2
alleles, DRB1*1501,*1502 or*1601 were at a lower risk of producing anti-donor HLA antibodies. 相似文献
100.