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Campath-1H (alemtuzumab) induction was used for renal transplantation in combination with sirolimus as immunosuppression. We previously reported a high (28%) rate of early rejection with this regimen, and now report 3-year outcomes. Twenty-nine patients were recipients of either deceased donor or non-HLA (Human Leukocyte Antigen) identical living donor primary renal allografts. Clinical parameters including infection, malignancy, kidney function, and kidney histology were followed prospectively for 3 years. Three-year cumulative graft and patient survival were 96% and 100%, respectively. Twenty patients were maintained on steroid-free immunosuppressive regimens, and 15 patients were maintained on monotherapy for immunosuppression (12 on sirolimus). No serious infectious complications were observed and two patients developed basal cell skin cancer. The 3-year results of our initial pilot study demonstrate good graft (96%) and patient (100%) outcomes. Campath-1H induction has yielded a high proportion of patients maintained on immunosuppressive monotherapy (57%) without serious infectious- and no malignancy-related complications. The reported regimen yielded novel insights into both Campath-1H and sirolimus therapy in renal transplantation. Because of the higher incidence of early rejection, we recommend a modified strategy of immunosuppression including a brief course of a calcineurin inhibitor.  相似文献   
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BACKGROUND: High-dose chemotherapy followed by autologous blood stem cell transplantation induces remission of plasma cell dyscrasia in patients with AL amyloidosis. The impact of this treatment on the glomerular amyloid mass is still unknown. METHODS: In the present study, the quantity of the renal amyloid mass before and more than 3 years after high-dose melphalan treatment and autologous blood stem cell transplantation was assessed in two patients. At the time of the second renal biopsy, both patients were in complete remission without detectable serum and urinary monoclonal IgA-lambda and a normal percentage of plasma cells in the bone marrow. RESULTS: In both patients with biopsy-proven AL amyloidosis, urinary protein excretion decreased from 7 g/24 h to <2 g/24 h more than 3 years after autologous blood stem cell transplantation. In contrast, glomerular amyloid deposits persisted, as shown in the second biopsy. CONCLUSION: Despite complete remission of the plasma cell dyscrasia and improvement of glomerular permeability, the amount of glomerular amyloid mass did not regress.  相似文献   
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OBJECTIVE: The studies showing the superior characteristics of ITA graft and its impact on the clinical results of coronary artery surgery were performed with ITA harvested almost exclusively as a pedicle. This study assesses the impact of ITA skeletonization on its innervation and reactivity. METHODS: Segments of skeletonized and non-skeletonized ITA were stained with antibodies against protein S-100 to look for the presence of sympathetic nerve fibers. The functional studies were performed on segments of discarded human pedicled ITA that were divided into two 3mm rings, one skeletonized and another non-skeletonized. We compared concentration-effect relationships for the contraction to norepinephrine and endothelium-dependent relaxation to acetylcholine and bradykinin, as well as endothelium-independent relaxation to sodium nitroprusside in skeletonized and non-skeletonized segments of the same ITA. RESULTS: Skeletonized ITA was devoid of protein S-100 positive nerve fibers. It contracted stronger (maximal response 37.0+/-2.04 vs. 25.4+/-1.83mN (P<0.001)) and was twice as sensitive to norepinephrine: pD(2) 6.03+/-0.10 vs. 5.70+/-0.12 (P=0.035). The endothelium-dependent relaxation responses did not differ between skeletonized and non-skeletonized ITA rings. The skeletonized ITA rings appeared over 10 times more sensitive to sodium nitroprusside: pD(2) 6.66+/-0.20 vs. 5.59+/-0.37 (P=0.012)-potency ratio 11.61. The maximal responses did not differ significantly: 112.0+/-6.71 vs. 129.4+/-16.4% (P=0.33). CONCLUSIONS: Skeletonization results in sympathectomy of ITA. It has no effect on endothelium-dependent relaxation but increases reactivity of ITA to norepinephrine. This augmented response to alpha-agonist is small, in comparison with over a ten-fold increase in sensitivity to sodium nitroprusside. Pedicled and skeletonized ITA are functionally significantly different vessels when studied in vitro.  相似文献   
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Summary: In this study, the administration of erythropoietin to haemodialysis patients revealed its immunomodulating properties. to dissociate the immunological effects of erythropoietin action from its haematological effects the patients in our study were administered recombinant human erythropoietin (rhEpo) at the doses that would not affect erythropoiesis. After baseline data had been obtained, six haemodialysis patients were given rhEpo (Eprex-Cilag) at the dose 7-10 U/kg bodyweight/s.c., three times a week, for 12 weeks. All patients maintained a stable haemoglobin concentration; no blood transfusions were required. Serum levels of tumour necrosis factor (TNF), IL-2 and IL-6 levels of the study patients and the four control patients, not receiving rhEpo, were monitored every 2 weeks. the levels of IL-6 and TNF remained unchanged; however, a low serum level of IL-2, recorded before therapy, increased gradually for 10 weeks until it reached the values observed in normal healthy humans (P<0.01). After that it dropped to the initial values. During the study the red blood cell numbers did not change. This study supports the thesis that erythropoietin administered to haemodialysis patients not only corrects anaemia but also independently modulates immunological response.  相似文献   
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A patient undergoing treatment for abdominal lymphoma presented with a superior vena cava (SVC) syndrome. The presence of a wide mediastinum and "nodular" mediastinal densities on CT presented a diagnostic problem, necessitating thoracotomy. The thoracotomy was negative for tumor or infection. We believe that the presence of an indwelling catheter and mediastinal lipomatosis resulted in the SVC syndrome. The "nodular" densities represented an unusual set of mediastinal collaterals that must be distinguished from adenopathy.  相似文献   
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Exposure of dark-adapted chicks to near ultraviolet (UV-A) light significantly decreased melatonin (MEL) content and the activity of serotonin N-acetyltransferase (AA-NAT; the penultimate and key regulatory enzyme in MEL production) in the pineal glands. Significant reduction in MEL level and AA-NAT activity was also found in pineals of animals whose heads were covered with black opaque tape, an observation suggesting that in the chicken UV-A light perceived by the eyes alone is capable of affecting MEL synthesis in the pineal gland. Covering the chick's eyes, in addition to the head, totally blocked the studied UV-A action. Although SCH 23390 (a selective D1-dopamine receptor antagonist), injected directly into both eyes at a dose of 10 nmol/eye, prevented the decline in pineal AA-NAT activity produced by retinal illumination with white light, the drug did not modify the UV-A light-evoked decrease in the enzyme activity. MK-801 (a selective antagonist of NMDA glutamate receptors; 1 nmol/eye) abolished the suppressive action of UV-A light on pineal AA-NAT activity, but it was inactive in the case of white light. Intraocularly injected sulpiride and CNQX (selective antagonists of D2-dopamine and AMPA/kainite glutamate receptors, respectively) had no effect on the actions of both UV-A and white light (acting on the eyes only) on pineal AA-NAT activity. It is concluded that in the chick retinally perceived UV-A light generates a signal which suppresses MEL production in the pineal gland. At the level of the retina, such signal does not involve dopamine, but is dependent on the stimulation of NMDA glutamate receptors.  相似文献   
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Impaired conditioned taste aversion learning in APP transgenic mice   总被引:8,自引:0,他引:8  
Cognition in transgenic mouse models of Alzheimer's disease (AD) has been predominantly characterized in explicit spatial orientation tasks. However, dementia in AD encompasses also implicit memory systems. In the present study a line of transgenic mice (TgCRND8) encoding a double mutated allele of the human amyloid precursor protein (APP) genes was evaluated in an implicit associative learning task of conditioned taste aversion (CTA). CTA is a form of Pavlovian classical conditioning, in which a mouse learns to avoid a novel taste of saccharine (conditioned stimulus) paired with an experimentally induced (systemic injection of lithium chloride) nausea (unconditioned stimulus). In contrast to conditioned non-Tg mice, TgCRND8 APP mice developed weaker aversion against saccharine and quickly increased its consumption in repeated tests. These results indicate that TgCRND8 mice show a significant impairment not only in explicit spatial memory, as has been previously shown [Nature 408 (2000) 979], but also in implicit memory. Control experiments confirmed that TgCRND8 and non-Tg mice had comparable taste sensitivities in response to appetitive as well as aversive tastes. The study suggests that the CTA paradigm can be a sensitive tool to evaluate deficits in implicit associative learning in APP transgenic mouse models of AD.  相似文献   
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