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991.
Roesch-Ely D Scheffel H Weiland S Schwaninger M Hundemer HP Kolter T Weisbrod M 《Psychopharmacology》2005,178(4):420-430
Rationale Executive control (EC) has different subcomponents, e.g., response inhibition (measured, for example, by the Stroop task) and working memory (WM—measured, for example, by delayed response tasks, DRT). EC has been associated with networks involving the prefrontal cortex (PFC). Moreover, there is evidence that dopamine agonists, especially those with a D1 profile, may modulate EC, since in the PFC D1 subtype receptors are more abundant.Objective This study aimed to selectively distinguish whether D1 versus D2 dopamine agonism differentially influences EC related to the inhibition of irrelevant information and WM. Because of its D1 component, we predicted that the administration of pergolide (mixed D1/D2 agonist), in comparison with bromocriptine (D2 selective agonist) and placebo, would enhance performance in both EC tasks. Using a lateralized Stroop task, we predicted a decrease in the interference effect, as well as error rates, while no increase in facilitation effects. For the DRT task, we predicted fewer error scores in the delay condition.Methods Forty male healthy subjects participated in this randomized, double-blind, placebo-controlled, crossover study.Results For the Stroop task no superiority of pergolide was found; however, with bromocriptine, decreased interference was found. No modulation of lateralization effects was shown in interference measures. Moreover, subjects on pergolide showed an absence of facilitation effects. No effects of either agonist were found for the DRT.Conclusion Our findings suggest that dopamine agonists modulate two EC tasks differently. Furthermore, there seems to be a selective modulation of different aspects of the Stroop task. 相似文献
992.
Lang PA Kempe DS Akel A Klarl BA Eisele K Podolski M Hermle T Niemoeller OM Attanasio P Huber SM Wieder T Lang F Duranton C 《Naunyn-Schmiedeberg's archives of pharmacology》2005,372(3):228-235
Osmotic shock, oxidative stress and Cl− removal activate a non-selective Ca2+-permeable cation conductance in human erythrocytes. The entry of Ca2+ leads to activation of a scramblase with subsequent exposure of phosphatidylserine at the cell surface. Phosphatidylserine
mediates binding to phosphatidylserine receptors on macrophages which engulf and degrade phosphatidylserine exposing cells.
Moreover, phosphatidylserine exposure may lead to adherence of erythrocytes to the vascular wall. In the present study, we
explored whether activation of the non-selective cation conductance and subsequent phosphatidylserine exposure might be influenced
by catecholamines. Phosphatidylserine exposure has been determined by FITC-annexin V binding while cell volume was estimated
from forward scatter in FACS analysis. Removal of Cl− enhanced annexin binding and decreased forward scatter, an effect significantly blunted by the β agonist isoproterenol (IC50 approx. 1 μM). Fluo-3 fluorescence measurements revealed an increase of cytosolic Ca2+ activity following Cl− removal, an effect again significantly blunted by isoproterenol exposure (10 μM). Whole-cell patch-clamp experiments performed
in Cl− free bath solution indeed disclosed a time-dependent inactivation of a non-selective cation conductance following isoproterenol
exposure (10 μM). Phenylephrine (IC50<10 μM), dobutamine (IC50 approx. 1 μM) and dopamine (IC50 approx. 3 μM) similarly inhibited the effect of Cl− removal on annexin binding and forward scatter. In conclusion, several catecholamines inhibit the Cl− removal-activated Ca2+ entry into erythrocytes, thus preventing increase of cytosolic Ca2+ activity, subsequent cell shrinkage and activation of erythrocyte scramblase. The catecholamines thus counteract erythrocyte
phosphatidylserine exposure and subsequent clearance of erythrocytes from circulating blood. 相似文献
993.
Recurrent central neurocytomas 总被引:4,自引:0,他引:4
994.
Piras F Colombari R Minerba L Murtas D Floris C Maxia C Corbu A Perra MT Sirigu P 《Cancer》2005,104(6):1246-1254
BACKGROUND: To establish the prognostic value of immune system cells that infiltrate melanoma, the authors evaluated the distribution and density of T lymphocyte subsets, macrophages, and dendritic cells in samples of primary cutaneous melanoma from 47 patients with Stage I and II melanoma according to the American Joint Committee on Cancer staging system. METHODS: Immunohistochemical demonstrations of CD8 and CD4 lymphocytes, CD68 macrophages, human leukocyte antigen-D-related (HLA-DR) cells, S-100 protein, and melanoma-associated antigens Melan A and HMB-45 were performed. The results were derived from independent histopathologic reviews by two pathologists. The low-density, moderate-density, and high-density groups of cells that infiltrated the base of the tumor during the vertical growth phase were compared with the overall survival rate using the Kaplan-Meier method and the log-rank test. Clinical variables (gender, age, tumor location, Clark level, vascular/lymphatic invasion, and thickness) also were analyzed. RESULTS: The CD8 lymphocytes exhibited independent statistically positive significance in survival (log-rank test, 8.49; P = 0.01) between patients in different lymphocyte density groups. There was a difference in 5-year survival among patients in the high-density group (78.8%), the moderate-density group (44.4%), and the low-density group (25.0%). The CD4 lymphocytes, which were less numerous than CD8 cells, had similar distribution. There also was a correlation of HLA-DR cells with overall survival (log-rank test, 5.29; P = 0.02). CD68 cell density was not found to be correlated with survival. CONCLUSIONS: The presence and number of infiltrating CD8 lymphocytes as well as the overall occurrence of HLA-DR cells may be considered independent, favorable prognostic factors in melanoma. The current results may be important for identifying other prognostic factors with which to evaluate disease progression and develop immune therapies for patients with melanoma. 相似文献
995.
996.
997.
Carano A De Berardis D Gambi F Salerno MR Campanella D Castrovilli M Cotellessa C Ferro FM 《Annali italiani di chirurgia》2005,76(5):461-464
The problem of relationship between obesity and psychological distress is debated in the literature wherein a lot of studies exists with controversial results. The phenomenon of obesity is actually considered with criteria aimed to evaluate almost exclusively the weight excess. Even if such criteria have the advantage to permit a scientific communicability, in the clinical settings the focus of obesity involves medical as well psychiatric aspects. The psychological aspects that may have a relevant role in the development of obesity must be recognized and distinguished from those that may be a direct consequence of obesity itself. In fact, certain obese subjects (no-binge obese) may not experience any psychological distress during lifetime whereas other obese subjects (binge obese) may have a significant and highly distressing psychological suffering. Therefore, obese persons seem to represent a heterogeneous population with different adaptive characteristics who may show several and complex psychological mechanisms and distresses. A psychotherapeutic approach seems to be essential to treat such psychological distress that may heavily concur to the development and the maintenance of obesity. 相似文献
998.
999.
Cugini D Azzollini N Gagliardini E Cassis P Bertini R Colotta F Noris M Remuzzi G Benigni A 《Kidney international》2005,67(5):1753-1761
BACKGROUND: Ischemia/reperfusion (I/R) injury after organ transplantation is a major cause of delayed graft function. Following I/R, locally produced CXC chemokines attract and activate granulocytes, which in turn promote graft damage. METHODS: We examined the involvement of granulocyte recruitment via the CXCR2 pathway in a rat model of 4 hours cold ischemia followed by kidney transplantation. Serum creatinine and intragraft granulocyte infiltration were monitored in the early phase posttransplant. A CXCR2 inhibitor, repertaxin, was given to recipients before transplantation (at -24 hours or -8 hours or -2 hours), immediately before reperfusion and 2 hours later. RESULTS: An increase of granulocyte chemoattractant CINC-1/interleukin-8 (IL-8) mRNA expression after I/R both in syngeneic and allogeneic transplantation was associated with a marked infiltration of granulocytes in renal tissue. In syngeneic transplantation, Lewis rats given 15 mg/kg repertaxin 24 hours before surgery had granulocyte graft infiltration and serum creatinine levels significantly reduced in respect to vehicle-treated animals. Intermediate effects were observed with 5 mg/kg, whereas the dose of 30 mg/kg had toxic effects. We found that reducing the pretreatment time to 8 hours before surgery was still effective. Prevention of granulocyte infiltration and serum creatinine increase was also obtained in allogeneic transplantation, when Brown Norway recipients of Lewis kidneys were given 15 mg/kg repertaxin starting 8 hours before surgery. CONCLUSION: Repertaxin treatment of the recipient animal was effective in preventing granulocyte infiltration and renal function impairment both in syngeneic and in allogeneic settings. The possibility to modulate I/R injury in this rat model opens new perspectives for preventing posttransplant delayed graft function in humans. 相似文献
1000.
Pretransplant donor peripheral blood mononuclear cells infusion induces transplantation tolerance by generating regulatory T cells 总被引:2,自引:0,他引:2
Cavinato RA Casiraghi F Azzollini N Cassis P Cugini D Mister M Pezzotta A Aiello S Remuzzi G Noris M 《Transplantation》2005,79(9):1034-1039
BACKGROUND: It was suggested that maintenance of tolerance to organ transplantation may depend on the formation of T regulatory cells. METHODS: Lewis (LW) rats were made tolerant to a Brown Norway kidney by pretransplant donor peripheral blood mononuclear cells (PBMC) infusion. At greater than 90 days after transplantation, lymph node cells (LN) and graft-infiltrating leukocytes (GIL) alloreactivity was tested in mixed lymphocyte reaction (MLR), coculture, and transwell experiments. GIL phenotype was analyzed by FACS. mRNA expression of cytokines and other markers was analyzed on CD4+ T cells from LN. The tolerogenic potential of tolerant cells in vivo was evaluated by adoptive transfer. RESULTS: Tolerant LN cells showed a reduced proliferation against donor stimulators but a normal anti-third-party alloreactivity. In coculture, these cells inhibited antidonor but not antithird-party reactivity of na?ve LN cells. Interleukin (IL)-10 and FasL mRNA expression was up-regulated in tolerant CD4+ T cells, but an anti-IL-10 monoclonal antibody (mAb) only partially reversed their inhibitory effect. Immunoregulatory activity was concentrated in the CD4+ CD25+ T-cell subset. In a transwell system, tolerant T cells inhibited a na?ve MLR to a lesser extent than in a standard coculture. Regulatory cells transferred tolerance after infusion into na?ve LW recipients. CD4+ T cells isolated from tolerized grafts were hyporesponsive to donor stimulators and suppressed a na?ve MLR against donor antigens. CONCLUSIONS: Donor-specific regulatory T cells play a role in tolerance induction by donor PBMC infusion. Regulatory activity is concentrated in the CD4+ CD25+ subset and requires cell-to-cell contact. Regulatory CD4+ T cells accumulate in tolerized kidney grafts where they could exert a protective function against host immune response. 相似文献