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Modified method of exchange transfusion in sickle cell disease   总被引:1,自引:0,他引:1  
The treatment of various complications of sickle cell disease has included red cell exchange in the past, and the development of automated pheresis equipment has greatly simplified such exchanges. Traditionally, the patient's red cells have been exchanged while their plasma was returned to them. Recently, plasma factors have been thought to play a role in the pathogenesis of vasoocclusive events. Therefore, we performed whole blood exchange, which consisted of replacement of the patient's plasma with albumin and saline in addition to the usual replacement of erythrocytes. A total of 32 whole blood exchanges were performed on 12 patients with a variety of complications of their disease. The procedure was done using standard pheresis equipment and was relatively simple to perform. There were no serious complications and the clinical outcome was good with 10 out of 12 patients experiencing improvement.  相似文献   
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Heterologous anti-lymphocyte globulin (ALG) is known to contain panagglutination activity and may cause a positive direct antiglobulin test in a renal allograft recipient. Three patients are reported in whom the passively acquired antibody showed apparent specificity in the Lutheran blood group system. The sera of these patients and eluates from their red cells displayed reactivity consistent with a Lutheran-related antibody. While the neat ALG acted as a panagglutinin, the Lutheran system specificity appeared only following dilution of the ALG. This specificity did not appear to represent a separate, distinguishable antibody in the ALG product. Before considering the utilization of units of the rare Lu(a-b-) phenotype for transfusing a renal allograft patient who has a Lutheran-related antibody, investigation of ALG as a source of that antibody should be conducted.  相似文献   
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To determine the characteristics of blood donors in western Venezuela, we collected data from 1983 to 1985 on 31,320 volunteer donors at the Blood Bank of the State of Zulia in Maracaibo. Fifty-nine percent of the donors were blood group O, 30 percent were group A, 9 percent were group B, and 2 percent were group AB. Most of the donors (93%) were Rh positive. One percent of donors had positive reactions to hepatitis B surface antigen, 3.15 percent for syphilis, 1.43 percent for antibodies to Trypanosoma cruzi, and 0.32 percent to human immunodeficiency virus antibodies. About one-half of the donors were between 18 and 30 years old, and only 10 percent were women. To determine if iron deficiency anemia was a cause for the small size of the female donor pool, we measured serum ferritin in 50 first-time female donors. Ten of these (20%) had serum ferritin values below normal, and the distribution of serum ferritin levels of all 50 was very similar to that reported for frequent donors in Europe and the United States, with a clustering of ferritin values between 10 and 70 ng per ml. The data indicate that blood donors in western Venezuela are markedly different from those in the United States and that iron supplementation may be indicated for female Venezuelan donors.  相似文献   
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The Ewing sarcoma family of tumors (ESFT) includes classic Ewing sarcoma of the bone, extraosseous or soft tissue Ewing sarcoma, Askin tumors of the chest wall, and peripheral primitive neuroectodermal tumors of the bone and soft tissues. They share a common neural histogenesis, tumor genetics and biology. The genetic hallmark of the ESFT is the presence of t(11;22)(q24;q12), which creates the EWS/FLI1 fusion gene and results in the expression of a chimeric protein. Although Ewing tumors can occur at any age, the great majority are found in individuals less than 20 years of age. We herein report a case of gastric Ewing sarcoma in a 68-year-old male. This patient illustrates the second reported occurrence of primary Ewing sarcoma in the stomach and the first reported with the t(11;22)(q24;q12) gene translocation.  相似文献   
39.
BACKGROUND: The well-known immune deficiency of the chronic alcoholic dictates the need for a long-term rodent ethanol administration model to evaluate the baseline immunologic effects of chronic ethanol abuse, and investigate the genetic determinants of those effects. Much published work with rodents has shown clearly that acute ethanol administration and short-term ethanol-containing liquid diets both cause elevated corticosterone and can cause significant thymocyte, pre-B cell and peripheral lymphocyte losses. Such losses may mask more subtle alterations in immune homeostasis, and in any case are generally short-lived compared with the span of chronic ethanol abuse. Thus, it is important to have a model in which long-term immune alterations can be studied free of corticosteroid-induced cell losses. METHODS: We have utilized chronic 20% (w/v) ethanol in water administration to several mouse strains for prolonged periods of time and evaluated serum corticosterone, immunologic stress parameters, and other organ changes by standard methods. RESULTS: We now confirm earlier reports that chronic ethanol in water administration to mice does not produce net elevations of corticosterone, although diurnal variation is altered. Importantly, there is neither selective loss of immune cell populations known to be corticosteroid sensitive, CD4+CD8+ thymocytes and pre-B cells, nor are changes observed in the histologic appearance of the thymus. Nonetheless, there are significant chronic ethanol effects in other tissues, including reduced heart weight, mild hepatic steatosis, alterations of gut flora, increased serum peptidoglycan, and as published elsewhere, immune system abnormalities. CONCLUSIONS: This model of ethanol administration is convenient, sustainable for up to 1 year, demonstrably feasible in several mouse strains, permits good weight gains in most strains, and results in significant changes in a number of organs. The administration method also will permit modeling of long-term steady abuse punctuated by major binges, and is suitable for supplementation studies using water soluble additives. Overall, the method is useful for a wide range of studies requiring a chronic low-stress method of ethanol administration.  相似文献   
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BACKGROUND: Transfusion therapy is frequently used to prevent morbidity in sickle cell disease (SCD), and subsequent iron overload is common. The objective of this study was to evaluate the current standard of care in monitoring iron overload and related complications in patients with SCD compared to thalassemia (Thal). STUDY DESIGN AND METHODS: A cross‐sectional study was conducted at 31 hematology clinics in the United States, Canada, or the United Kingdom. Patients who received transfusions with a mean serum ferritin level of least 2000 ng per mL were eligible. A total of 199 patients with SCD (113 female; 24.9 ± 13.2 years) and 142 with Thal (66 female; 25.8 ± 8.1 years) were recruited, and data were collected between 2001 and 2003 by interview and medical record review. RESULTS: Although both groups were recruited on the basis of significant iron overload, the likelihood of performing a liver biopsy for routine iron monitoring was significantly higher (odds ratio [OR], 3.4; 95% confidence interval [CI], 2.2‐5.3) in Thal than SCD. Thal patients were also more likely to be screened for iron‐related organ injury including an echocardiograph for cardiomyopathy (OR, 2.6; p < 0.001; 95% CI, 1.6‐4.2), alanine aminotransferase for liver function (OR, 8.3; CI, 1.05‐64.4), and thyroid‐stimulating hormone for hypothyroidism (OR, 12.3; CI, 7.0‐21.5). For adult SCD patients, those maintained on simple transfusion with a serum ferritin level of greater than 2500 ng per mL were the least likely to have a liver biopsy (p < 0.03). CONCLUSIONS: These data highlight the unsystematic monitoring of iron and related organ injury in SCD. Until the relationship between iron and related comorbidities is better understood, routine monitoring of iron overload in SCD patients who receive transfusions should be considered a standard part of clinical care.  相似文献   
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