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Anneloes Dirks Lucianne Groenink Koen G C Westphal Jocelien D A Olivier P Monika Verdouw Jan van der Gugten Mark A Geyer Berend Olivier 《Neuropsychopharmacology》2003,28(10):1790-1798
Chronically elevated levels of corticotropin-releasing factor (CRF) in transgenic mice overexpressing CRF in the brain (CRF-OE) appear to be associated with alterations commonly associated with major depressive disorder, as well as with sensorimotor gating deficits commonly associated with schizophrenia. In the present study, we tested the hypothesis that antipsychotics may be effective in normalizing prepulse inhibition (PPI) of acoustic startle in CRF-OE mice, which display impaired sensorimotor gating compared to wild-type (WT) mice. The typical antipsychotic haloperidol and atypical antipsychotic risperidone improved PPI in the CRF-OE mice, but were ineffective in WT mice. The atypical antipsychotic clozapine did not influence PPI in CRF-OE mice, but reduced gating in WT mice. This effect of clozapine in the CRF-OE mice may thus be regarded as a relative improvement, consistent with the observed effect of haloperidol and risperidone. As expected, the anxiolytic, nonantipsychotic chlordiazepoxide was devoid of any effect. All four compounds dose-dependently reduced the acoustic startle response irrespective of genotype. These results indicate that antipsychotic drugs are effective in improving startle gating deficits in the CRF-OE mice. Hence, the CRF-OE mouse model may represent an animal model for certain aspects of psychotic depression, and could be a valuable tool for research addressing the impact of chronically elevated levels of CRF on information processing. 相似文献
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H. S. Pollinger M. D. Stegall J. M. Gloor S. B. Moore S. R. Degoey N. A. Ploeger W. D. Park H. S. Pollinger M. D. Stegall J. M. Gloor S. B. Moore S. R. Degoey N. A. Ploeger W. D. Park 《American journal of transplantation》2007,7(4):857-863
The immunologic risk associated with donor-specific antibodies (DSA) against Class II human leukocyte antigens (HLA) in kidney transplant (KTx) recipients is unclear. The aim of this study was to determine the outcome of KTx when DSA was detected only against HLA Class II. To isolate the impact of anti-Class II DSA, we retrospectively analyzed 12 KTx recipients who at baseline had a positive B-cell flow cytometric crossmatch (FXM) and a negative T-cell FXM. Using alloantibody specification analysis, 58.3% (7/12) had DSA against donor Class II and 41.7% had no demonstrable DSA. Biopsy-proven AMR occurred in 57% (4/7) in the Class II(+) group and 0% in the Class II(-) group (p > 0.05). Peritubular capillaries stained positive for C4d in 86% (6/7) of the Class II(+) patients and in 40% (2/5) of the Class II(-) patients (p > 0.05). One patient in the Class II(+) group lost their graft at 3 months to accelerated transplant glomerulopathy, while all other grafts were functioning 3-37 months posttransplant despite the persistence of anti-Class II DSA. We conclude that KTx recipients with clearly defined anti-Class II DSA are at risk for humoral rejection suggesting that desensitization and/or close posttransplant monitoring may be needed to prevent AMR. 相似文献
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Claus D. Eisenbach Andreas Gldel Monika Terskan-Reinold Ulrich S. Schubert 《Macromolecular chemistry and physics.》1995,196(4):1077-1091
The synthesis and properties of segmented ABA triblock and (AB)n multiblock copolymer systems with 6,6′-disubstituted 2,2′-bipyridine (bpy) building blocks B and poly(oxytetramethylene) soft segments A are described. The access to the disubstituted bipyridines in large scale quantities was achieved by modification of conventional synthetic routes. In the presence of copper(I) ions these polymers formed mononuclear [Cu(I)(bpy)2] complexes in solution through self-assembly. The complexed copolymers were microphase separated systems in bulk with nano to mesoscopic superstructures consisting of copper-bpy complex aggregates in a polyether matrix. The thermal, mechanical and elastomer properties of the block copolymers varied with composition. 相似文献
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M. Myslak H. Amer P. Morales M. E. Fidler J. M. Gloor T. S. Larson M. D. Stegall F. G. Cosio 《American journal of transplantation》2006,6(7):1660-1665
Increasing numbers of patients receive kidney transplants before initiation of dialysis or shortly thereafter. Some of these patients have significant proteinuria pre-transplant making the interpretation of post-transplant proteinuria problematic. In this study, we evaluated post-transplant proteinuria in 115 patients who had urine protein measured within 3 months of transplant and assessed the association of proteinuria with allograft pathology. Proteinuria declined rapidly from 3650 +/- 3702 mg/day pre-transplant to 550 + 918 at 3 weeks (p < 0.0001) and continued to decline until 1 year post-transplant (472 +/- 1116, p < 0.0001 vs. 3 weeks). Proteinuria greater than 3000 mg/day was present in 48 patients (42%) pre-transplant, in 1 patient (1%) at 3 weeks and in 4 patients (4%) at 1 year. Surveillance graft biopsies were done at 1 year in 93% of patients. Proteinuria > or = 1500 mg/day and/or an absolute increase in proteinuria > 500 mg/day after 3 weeks post-transplant was associated with allograft glomerular pathology. In conclusion, pre-transplant proteinuria, even when high grade, declines rapidly after transplantation. Failure to decline or persistence of proteinuria greater than 1500 mg/day is indicative of allograft pathology. 相似文献
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