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Alemtuzumab is a powerful lymphocyte depleting antibody currently being evaluated in solid organ transplantation. This paper describes 5-year results of a single center study of alemtuzumab as induction in renal transplantation. Thirty-three renal transplant recipients received 20 mg alemtuzumab on day 0 and 1, followed by half-dose cyclosporin monotherapy (trough concentration 75-125 ng/mL) from day 3. They were compared in a retrospective contemporaneous-controlled manner with 66 kidney transplant recipients transplanted in the same period and center who received conventional immunosuppression with cyclosporin, azathioprine and prednisolone. In the alemtuzumab group 12% of recipients died compared to 17% in the control group (p = 0.48); likewise graft loss was similar in both groups (21% vs. 26%, respectively, p = 0.58). Incidence of acute rejection was also comparable at 5 years (31.5% vs. 33.6%), although the pattern of rejection was different with 14% patients in the alemtuzumab group experiencing rejection over 1 year post-transplant compared to none in the control group. There was no significant difference between groups in terms of infection or serious adverse events. While acknowledging the limitations of a relatively small single-center study, results suggest that alemtuzumab induction allowed satisfactory long-term patient and graft survival equivalent to that seen with standard triple immunosuppression, while avoiding steroid therapy.  相似文献   
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In 1987, die Department of Health in the UK set up a working party to identify reasons contributing to a shortfall in donor organs. One recommendation was reimbursement to the District Health Authorities for costs incurred in providing the donor organs. The figure chosen was not to be seen as an incentive to donate organs, merely as an appropriate compensation for the costs incurred. There would be no direct payment to doctors, trustees or relatives of the donor. With the development of the competitive health care environment in the United Kingdom, the reimbursement of donating hospital costs is being considered with these data.  相似文献   
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One systemic effect of burn trauma is skeletal muscle weakness. This is the result of changes in second messenger systems involving calcium (Ca2+). Kinetic analysis of Ca2+ from cellular compartments of skeletal muscle of mice that were subjected to small burn injury (20% body surface area) was performed. Muscles of the burn group showed an increased 45Ca2+ uptake maxima compared with those of time-matched control groups. Also, 45Ca2+ efflux analysis showed a lack of differentiation between electrically stimulated tissues and nonstimulated tissues that was easily observed in time-matched control groups. This lack of differentiation indicated changes in intracellular compartmentation. It can be speculated that burn trauma may have a regulatory role in the excitation-contraction coupling mechanism by altering myoplasmic levels of Ca2+ even before skeletal muscle dysfunction occurs. These findings suggest that agents capable of controlling myoplasmic Ca2+ levels may aid in alleviating chronic skeletal muscle dysfunction in patients with burns.  相似文献   
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The present study investigated the specific ways by which cytotoxicity due to glutamate receptor stimulation could be attenuated by the administration of agonists and antagonists of the ionotropic and metabotropic glutamate receptors within the nucleus basalis magnocellularis (NBM) of rats as measured by cortical choline acetyltransferase activity. The results of these studies suggest that (1) the cytotoxicity of ibotenate to NBM cholinergic cells is not dependent upon stimulation of metabotropic glutamate receptors, but results from activation of (NMDA) receptors, (2) the cytotoxicity of quisqualate to cholinergic cells within the NBM is not dependent upon stimulation of NMDA or metabotropic receptors, and (3) the cytotoxicity of NMDA was prevented by administration (i.p.) of the un-competitive NMDA antagonist memantine (30 mg/kg), resulting in plasma levels of 2.5 μg/ml, a concentration known to block efficiently NMDA receptors in vitro. Finally, performance of a food-motivated, delayed-alternation task on a T-maze was impaired by injections of NMDA into the NBM, but was prevented by co-administration of NMDA with memantine.  相似文献   
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The purpose of this study was to evaluate the dose to normal tissues as a function of increasing margins around the lumpectomy cavity in accelerated partial breast irradiation (APBI) using 3D-conformal radiotherapy (3DCRT). Eight patients with Stage 0-I breast cancer underwent treatment planning for 3DCRT APBI. The clinical target volume (CTV) was defined as a 15-mm expansion around the cavity limited by the chest wall and skin. Three planning target volumes (PTV1, PTV2, PTV3) were generated for each patient using a 0, 5-, and 10-mm expansion around the CTV, for a total margin of 15, 20, and 25 mm. Three treatment plans were generated for every patient using the 3 PTVs, and dose-volume analysis was performed for each plan. For each 5-mm increase in margin, the mean PTV:total breast volume ratio increased 10% and the relative increase in the mean ipsilateral breast dose was 15%. The mean volume of ipsilateral breast tissue receiving 75%, 50%, and 25% of the prescribed dose increased 6% to 7% for every 5 mm increase in PTV margin. Compared to lesions located in the upper outer quadrant, plans for medially located tumors revealed higher mean ipsilateral breast doses and 20% to 22% more ipsilateral breast tissue encompassed by the 25% IDL. The use of 3DCRT for APBI delivers higher doses to normal breast tissue as the PTV increases around the lumpectomy cavity. Efforts should be made to minimize the overall PTV when this technique is used. Ongoing studies will be necessary to determine the clinical relevance of these findings.  相似文献   
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Campath-1M is a rat monoclonal IgM antibody that binds human complement and recognizes virtually all peripheral human mononuclear cells. It is known to be effective in T cell depletion of bone marrow grafts, and encouraging results were obtained in a pilot study in which the antibody was used in prevention and treatment of rejection of kidney, pancreas, and liver allografts. In this randomized controlled clinical trial, Campath-1M has been evaluated as a prophylactic agent following renal allografting. It is shown that patients who received a 10-day course of the antibody immediately postoperatively, in addition to standard therapy with high-dose cyclosporine (17 mg/kg), experienced a significantly lower incidence of early acute cellular rejection than control patients who received cyclosporine alone. There was no evidence of "rebound" rejection following the end of antibody treatment to suggest that rejection had merely been delayed. However, patients who received this additional immunosuppression experienced a significantly higher incidence of serious infections than controls, this negating any benefit from the treatment in terms of graft survival. Thus, a monoclonal antibody of broad specificity directed against lymphocytes may be effective as a prophylactic agent after organ transplantation but its use should be accompanied by a reduction in other immunosuppressive drugs.  相似文献   
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