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Extracorporeal immune adsorption with staphylococcal protein A (SPA) columns can remove immune complexes and immunoglobulins in the treatment of a variety of diseases. We present the case of an elderly man with neuropathy associated with monoclonal gammopathy, treated by 3 on-line SPA procedures. At the completion of these treatments his neuropathy relapsed, progressing to near-total paralysis. Return to a baseline clinical status required several months. The reason for this severe relapse is not clear. Possible explanations include SPA activation of T-lymphocytes, with release of gamma interferon and increased antigen recognition, or removal of an anti-idiotype control mechanism. We advise caution in the application of immunoadsorption to conditions in which it has not yet been evaluated. © 1992 Wiley-Liss, Inc.  相似文献   
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Since lung transplant recipients are susceptible to infections and inhaled pollution, many centers warn against pets. However, data supporting this recommendation are lacking. Our program is less restrictive regarding pets. This study, for the first time, investigates the association of pets with physiological and psychological parameters in these patients. A questionnaire concerning pets was sent to 104 lung transplant recipients. Lung function tests, levels of exhaled nitric oxide (FE(NO)), need for antibiotic treatments and hospitalizations, creatinine clearance, body mass index (BMI) and demographic data were assessed. Additionally, the questionnaire of life satisfaction (FLZ), a question on summarized life satisfaction (LS), the life orientation test (LOT), the hospital anxiety depression scale (HADS) and the social support questionnaire (F-SozU) were assessed. Response rate was 86%. Fifty-two percent defined themselves as pet owners, whereas 48% did not. The two groups did not differ in demographic or physiological data. Significant differences in FLZ (79/65, p = 0.04), in LS (4.3/3.9, p = 0.01), LOT (32/29, p = 0.006) and F-SozU (4.5/4.2, p = 0.04) were found in favor of pet owners. In lung transplant recipients keeping pets the frequency of somatic complications is not higher compared to lung transplant recipients without pets. After lung transplantation, pets are associated with a better quality of life.  相似文献   
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Cardiovascular diseases requiring surgical therapy in patients with prior liver transplantation are rare. Little is known about the outcome of patients with liver allograft undergoing cardiac surgery. Herein we report our experience in this patient population with an emphasis on operative outcomes and mid-term survival. Between January 1998 and December 2004, 12 patients (mean +/- standard deviation age 68 +/- 9 years, 7 [58%] male) with previous liver transplantation who underwent cardiac surgery were identified. Main outcome measures were hospital mortality, postoperative complications, allograft function, and long-term survival. There was no in-hospital mortality. Three major complications (25%) occurred, including 1 each (8%) of respiratory failure, renal failure, and biliary leakage. All complications were resolved by the time of discharge. Allograft dysfunction determined by an increase of liver function parameters was noticed in 4 (33%) and recovered before discharge. The average length of stay in intensive care unit was 72 +/- 45 hours, and the mean length of stay in hospital was 22 +/- 17 days. One- and 5-year survival was 91% +/- 8% and 67% +/- 14%, respectively. Cardiac surgery can be performed safely in liver transplant recipients with extremely low mortality and acceptable morbidities. Allograft dysfunction is a common finding, but it is transient, with early functional recovery. Five-year survival of liver recipients undergoing cardiac procedures is similar to that of the general population undergoing cardiac surgery. Our data suggest that these patients should be considered for cardiac surgery in reference centers with expertise in complex cardiac procedures and perioperative management of these highly specific patients.  相似文献   
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To determine whether liver repopulation with cell transplantation could be of therapeutic value in acute hepatic failure, it is necessary to establish the fate of transplanted hepatocytes. This study used dipeptidyl peptidase IV-deficient F344 rats as recipients to analyse the engraftment and proliferation of transplanted hepatocytes. Syngeneic hepatocytes were transplanted intrasplenically 24-30 h after induction of liver injury by D-galactosamine (GalN). Portosystemic shunting was analysed with 99m-Tc-labelled albumin microspheres. GalN-treated rats showed characteristic hepatic necrosis, inflammation, gamma-glutamyl transpeptidase activation, and regenerative activity, without increased portosystemic shunting (>99% 99m-Tc activity was in the liver in normal and GalN-treated rats). Transplanted cells entered hepatic sinusoids promptly and were observed in liver plates at 48 h. The number of transplanted cells increased in GalN-treated rats by approximately seven-fold (range two- to 12-fold), along with evidence for DNA synthesis between 3 and 14 days after cell transplantation and greater prevalence of larger transplanted cell clusters. These findings indicate that the liver can be safely repopulated in animals with acute liver failure, although the time required for regenesis of plasma membrane structures and proliferation in transplanted hepatocytes will need to be considered in developing therapeutic strategies.  相似文献   
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Recent studies have found electrical coupling to be more ubiquitous than previously thought, and coupling through gap junctions is known to play a crucial role in neuronal function and network output. In particular, current spread through gap junctions may affect the activation of voltage-dependent conductances as well as chemical synaptic release. Using voltage-clamp recordings of two strongly electrically coupled neurons of the lobster stomatogastric ganglion and conductance-based models of these neurons, we identified effects of electrical coupling on the measurement of leak and voltage-gated outward currents, as well as synaptic potentials. Experimental measurements showed that both leak and voltage-gated outward currents are recruited by gap junctions from neurons coupled to the clamped cell. Nevertheless, in spite of the strong coupling between these neurons, the errors made in estimating voltage-gated conductance parameters were relatively minor (<10%). Thus in many cases isolation of coupled neurons may not be required if a small degree of measurement error of the voltage-gated currents or the synaptic potentials is acceptable. Modeling results show, however, that such errors may be as high as 20% if the gap-junction position is near the recording site or as high as 90% when measuring smaller voltage-gated ionic currents. Paradoxically, improved space clamp increases the errors arising from electrical coupling because voltage control across gap junctions is poor for even the highest realistic coupling conductances. Furthermore, the common procedure of leak subtraction can add an extra error to the conductance measurement, the sign of which depends on the maximal conductance.  相似文献   
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BACKGROUND: Basophils represent an important source of inflammatory mediators and cytokines after IgE-dependent activation in human beings. OBJECTIVE: To assess the role of basophils in allergic asthma, we measured the number of basophils in the bronchial mucosa and their capacity to express IL-4 mRNA and protein during allergen-induced late asthmatic responses. METHODS: Fiberoptic bronchoscopic bronchial biopsies were obtained at 24 hours from sites of segmental bronchial allergen challenge and control sites in 19 patients with atopic asthma and 6 nonatopic healthy volunteers. Basophil numbers were assessed by immunohistochemistry through use of mAb 2D7. IL-4 mRNA--positive cells were detected through use of in situ hybridization and colocalized to basophils through use of sequential immunohistochemistry/in situ hybridization. IL-4 protein was detected and colocalized to basophils through use of dual immunohistochemistry. RESULTS: After allergen challenge, there was an increase in the median number of 2D7-positive basophils per square millimeter in the bronchial mucosa in patients with asthma (0.9 cells/mm(2) at baseline to 8.8 cells/mm(2) after challenge; P =.002), which also was significantly higher than what was seen in nonasthmatic controls (P =.01). Similarly, IL-4 mRNA--positive cells were increased at 24 hours in patients with asthma (1.4 to 14) in comparison with controls (0 to 0; P =.02). Colocalization studies revealed that 15% and 41% of the basophil population in patients with asthma after allergen-challenge expressed, respectively, IL-4 mRNA and protein. Conversely, 19% of IL-4 mRNA-positive cells and 72% of IL-4 protein--positive cells were accounted for by basophils. CONCLUSION: After allergen provocation in sensitive patients with atopic asthma, basophils are recruited to the bronchial mucosa and express IL-4 mRNA and protein, which might contribute to local IgE synthesis and/or tissue eosinophilia or other aspects of allergic inflammation during late responses and ongoing asthma.  相似文献   
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