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1.
The mechanism of cryoprecipitation of a monoclonal IgM kappa cryoglobulin (Mou) with a cold agglutinin activity of Pr2 specificity has been studied. By immunodiffusion this cryoglobulin reacted (by its Fab' fragment) with micellar GM3, a ganglioside bearing the Pr2 antigenic determinant. In contrast to previous reports that indicated a possible temperature dependent self-association of IgM molecules via an immunological interaction leading to cold precipitation, we could not detect any affinity of this cryoglobulin for IgM when we used passive hemagglutination or an indirect enzyme-linked immunosorbent assay (ELISA). However, a GM3-like ganglioside could be extracted, by drastic methods, from the cryoglobulin studied at 22 degrees C, whereas no GM3 was extracted from two control cryoglobulins. Some minor gangliosides (representing less than 25% of total amount of bound gangliosides) were also extracted from Mou cryoglobulin and these gangliosides were shown to crossreact with GM3, as they specifically bind to Mou cryoglobulin by ELISA. After cryoprecipitation the serum still contained a monoclonal anti-Pr2 IgM kappa. A GM3-like ganglioside could be extracted from this purified IgM, and cryoprecipitability could be induced by the addition of a minute amount of micellar GM3. These results suggest that Mou cryoglobulin circulates as an immune complex and that cryoprecipitation may depend on unique IgM-GM3 (or IgM-GM3 cross-reacting gangliosides) complexes.  相似文献   

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Background

Cold-stored platelets are increasingly being used to treat bleeding. Differences in manufacturing processes and storage solutions can affect platelet quality and may influence the shelf life of cold-stored platelets. PAS-E and PAS-F are approved platelet additive solutions (PAS) in Europe and Australia, or the United States respectively. Comparative data are required to facilitate international transferability of laboratory and clinical data.

Study Design and Methods

Single apheresis platelets from matched donors (n = 8) were collected using the Trima apheresis platform and resuspended in either 40% plasma/60% PAS-E or 40% plasma/60% PAS-F. In a secondary study, platelets in PAS-F were supplemented with sodium citrate, to match the concentration in PAS-E. Components were refrigerated (2–6°C) and tested over 21 days.

Results

Cold-stored platelets in PAS-F had a lower pH, a greater propensity to form visible (and micro-) aggregates, and higher activation markers compared to PAS-E. These differences were most pronounced during extended storage (14–21 days). While the functional capacity of cold-stored platelets was similar, the PAS-F group displayed minor improvements in ADP-induced aggregation and TEG parameters (R-time, angle). Supplementation of PAS-F with 11 mM sodium citrate improved the platelet content, maintained the pH above specifications and prevented aggregate formation.

Discussion

In vitro parameters were similar during short-term cold storage of platelets in PAS-E and PAS-F. Storage in PAS-F beyond 14 days resulted in poorer metabolic and activation parameters. However, the functional capacity was maintained, or even enhanced. The presence of sodium citrate may be an important constituent in PAS for extended cold storage of platelets.  相似文献   

4.
G Moroff  D Dende 《Transfusion》1983,23(6):484-489
Citrate-phosphate-dextrose-adenine (CPDA-1), containing 0.25 mM adenine (final concentration) and 25 percent more glucose than citrate-phosphate-dextrose (CPD), has extended the allowable storage time for red cells to 35 days. Studies were conducted to understand better the characteristics of stored CPDA-1 red cells in relation to the properties of stored CPD red cells. Units with hematocrits near 80 percent showed the following: First, adenosine triphosphate (ATP) and total adenine nucleotide levels of red cells stored with CPDA-1 remained essentially constant during the first 3 weeks of storage after which the levels decreased; with red cells stored with CPD, ATP, and adenine nucleotide, levels were decreased even after 1 week of storage. Second, the pattern of the fall in 2,3-diphosphoglycerate was similar in red cells stored with CPD and CPDA-1. Third, changes in plasma and red cell levels of sodium and potassium, and in plasma ammonia levels, were comparable in CPD and CPDA-1 units; changes in cation levels were most pronounced during the initial 2 weeks of storage. Fourth, hemolysis was much greater in units stored in CPDA-1 for 35 days than in units stored in CPD for 21 days. Fifth, residual glucose concentrations were adequate in units drawn in CPDA-1 and stored for 35 days. We conclude that the changes in the biochemical characteristics of units of red cells stored with CPD and CPDA-1 are similar in most instances with the notable exception of the better maintenance of adenosine triphosphate levels in red cells stored with CPDA-1.  相似文献   

5.
Red cells anticoagulated with citrate-phosphate-dextrose (CPD) or a commercial preservative solution containing adenine, sodium chloride, and mannitol (ADSOL) and stored in heat-sealed segments of plastic tubing were tested for antigen stability after refrigeration at 4 degrees C for up to 56 days. Reactivity of the A, B, c, D, K, Lea, Fya, M, and P1 antigens was maintained adequately during the storage period in both solutions. Heat-sealed segments containing red cells suspended in either CPD or ADSOL preservation solutions for up to 56 days appear acceptable for use in compatibility testing.  相似文献   

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Babesiosis is a malaria-like parasitic disease causing subclinical or mild illness in most cases. Splenectomized patients, however, may experience a more severe course. Although generally responsive to antibiotic therapy, several cases of severe babesiosis refractory to appropriate antibiotic therapy have been reported to respond promptly and dramatically to red blood cell (RBC) exchange transfusion. Although the role of HIV coinfection in babesiosis is uncertain, two previously reported cases raise a concern that it may predispose to a more severe clinical course. We report a third case of severe babesiosis in an HIV-positive splenectomized man, following travel to an endemic area. Antibiotic therapy, though initially effective, ultimately failed to prevent severe disease. RBC exchange transfusion resulted in prompt clinical improvement, which has been sustained during 26 months of follow-up. Although the patient has since developed various sequelae of HIV infection, including disseminated Kaposi's sarcoma, CMV retinitis, and enteritis, there has been no recurrence of observable parasitemia. In severe babesiosis, RBC exchange transfusion, combined with appropriate antibiotic therapy, appears to be a rapidly effective therapeutic modality which can induce sustained remissions. © 1993 Wiley-Liss, Inc.  相似文献   

8.
热释放-Ficoll分离-微柱凝胶法检测高冷凝集素患者ABO血型   总被引:1,自引:0,他引:1  
冷凝集素是一种冷自身抗体,是导致血型鉴定困难和交叉配血不合较为常见的因素。国内多采用试管法鉴定冷凝集素综合征患者的血型,最近有学者认为37℃预孵育一微柱凝胶法也可用于上述患者的血型鉴定,为此,笔者对该法进行局部改良,建立了热释放-Ficoll分离-微柱凝胶法,取得满意结果,现报告如下。  相似文献   

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10.
We previously reported that platelets become unresponsive to agonists when stimulated in combined suspension with aspirin-treated human umbilical vein endothelial cells. Inhibition occurred concomitant with metabolism of platelet-derived endoperoxides to prostacyclin by endothelial cells. We now demonstrate that if aspirin-treated platelets which fully respond to appropriate doses of agonists are exposed to aspirin-treated endothelial cells, they remain unresponsive despite absence of prostacyclin. Platelet inhibition is due in large part to ecto-ADPase activity on the endothelial cells. This was established by incubating aspirin-treated endothelial cells with 14C-ADP. Radio-thin layer chromatography and aggregometry demonstrated that 14C-ADP and induction of platelet activation decreased rapidly and concurrently. AMP accumulated transiently, was further metabolized to adenosine, and deaminated to inosine. The apparent Km of the endothelial cell ADPase was 33-42 microM and the Vmax 17-43 nmol/min per 10(6) cells, values in the range of antithrombotic potential. Thus, at least three complementary systems in human endothelial cells control platelet responsiveness: a cell-associated, aspirin-insensitive ADPase which functions in parallel with fluid phase autacoids such as the aspirin-inhibitable eicosanoids, and the aspirin-insensitive endothelium-derived relaxing factor.  相似文献   

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12.
BACKGROUND: Current additive solutions (ASs) for red blood cells (RBCs) do not maintain constant 2,3‐diphosphoglycerate (DPG) and adenosine triphosphate (ATP) levels during cold storage. We have previously shown that with a new AS called phosphate‐adenine‐glucose‐guanosine‐gluconate‐mannitol (PAGGGM), both 2,3‐DPG and ATP could be maintained throughout storage for 35 days. STUDY DESIGN AND METHODS: In this study, the mechanism underlying the effect of PAGGGM on RBC storage was studied in more detail. By using double‐erythrocytapheresis units (leukoreduced), a direct comparison could be made between the current AS saline‐adenine‐glucose‐mannitol (SAGM) and the experimental solution PAGGGM. During cold storage, several in vitro characteristics were analyzed. RESULTS: In agreement with our previous findings with single RBCs, PAGGGM maintained 2,3‐DPG and ATP levels for 35 days of cold storage. Furthermore, glucose consumption and lactate production were higher in PAGGGM units during the first 21 days of cold storage. Fructose‐1,6‐diphophate and dihydroxyacetone phosphate levels were also increased during the first 21 days of storage in PAGGGM units. CONCLUSION: These results indicate that it is likely that phosphofructokinase (PFK) activity is enhanced in PAGGGM units relative to SAGM units. After 21 days, PFK activity also decreases in PAGGGM units, but sufficient metabolic reserve in these units prevents depletion of 2,3‐DPG and ATP.  相似文献   

13.
The effect of platelets on the removal of white cells (WBCs) from 16 to 24-hour-old red cell (RBC) concentrates by filtration was studied. RBC concentrates with various concentrations of platelets and WBCs were filtered on a cellulose acetate column filter and on three polyester flatbed filters. The microscopic study revealed that lymphocytes and most monocytes were captured in the smaller pores of the fiber network, irrespective of the brand of filter, the type of filter material, or the prefiltration platelet amount in the RBC concentrates. In contrast, efficient granulocyte depletion depended on granulocyte-platelet interaction and on the filter material. In the presence of platelets, granulocytes were captured in the top part of the column filter or in the coarse layers of two of the flatbed filters, where platelets covered the fibers. Platelet depletion of the RBC concentrates prior to filtration diminished the contribution of these parts of the filters to granulocyte capture. A larger part of the column filter or the fine layers of the flatbed filters were now required for granulocyte capture. In one of the flatbed filters, granulocyte-platelet interaction occurred mainly in the fine layers, which ended in blockage of this filter after the filtration of variable volumes (250-600 mL) of standard RBC concentrates. A quantitative estimation of the effect of platelets on the WBC-reduction capacity found that all three flatbed filters had a highly significant decrease (p = 0.001) in WBC-reduction capacity for platelet-depleted or buffy coat-depleted RBC concentrates, as compared with standard RBC concentrates.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
微量板酶法测定红细胞内肌酸   总被引:2,自引:0,他引:2  
目的 建立一种红细胞内肌酸的测定方法。 方法 采用 CTase/SOX/POD三联酶氧化肌酸产生 H2 O2 ,通过偶联显色反应测定红细胞内肌酸。 结果 方法的线性范围为 0~ 2 0 0μmol/L;精密度 :批内 CV 0 .92 %~ 1 .5 1 % ,批间CV1 .2 8%~ 2 .1 2 % ;回收率 98.30 %~ 1 0 1 .69%。采用了 μmol/g Hb和 μmol/LRBC两种红细胞内肌酸测定的单位表示方法 ,消除了实验误差对结果产生的影响。 2 86例健康人红细胞肌酸参考值分别为男性 1 .93± 0 .36μmol/g Hb,684 .3± 1 2 7.5μmol/LRBC;女性 2 .1 7± 0 .4 1 μmol/g Hb,75 9.4± 1 37.9μmol/LRBC。 结论 本方法简便、可靠、线性范围广、特异性好 ,适合作为红细胞内肌酸的常规测定。  相似文献   

15.
The development of red cell (RBC) alloantibodies in infants less than 4 months of age is believed to be rare. Though there are no well-documented published accounts, the formation of alloanti-E in a multiply transfused 11-week-old infant is reported here. The infant, blood group B, D +, developed necrotizing enterocolitis and renal failure requiring 31 transfusions of washed and unwashed RBCs (group B and group O), as well as fresh-frozen plasma and platelets. Six weeks after the first blood transfusion, alloanti-E was detected. The anti-E weakly agglutinated R2R2 screening RBCs at 37 degrees C and sensitized these RBCs to react with anti-IgG. The infant's RBCs were typed as E-. Passive transfer of alloanti-E was ruled out by the negative antibody screening tests of each donor unit and the absence of any RBC alloantibodies in the mother's serum. Stored samples of the infant's sera were tested, and anti-E was shown to be present approximately 11 days after exposure to a known E+ RBC unit. The appearance of alloanti-E in this time frame is consistent with a secondary immune response. Primary immunization most likely took place in the first 4 weeks of transfusion therapy.  相似文献   

16.
Cell cycle regulators, such as the CDC25 phosphatases, are potential targets for the development of new anticancer drugs. Here we report the identification and the characterization of BN82685, a quinone-based CDC25 inhibitor that is active in vitro and in vivo. BN82685 inhibits recombinant CDC25A, B, and C phosphatases in vitro. It inhibits the growth of human tumor cell lines with an IC(50) in the submicromolar range, independently of their resistance to chemotherapeutic agents. This inhibitory effect is irreversible on both the purified CDC25 enzyme in vitro and on tumor cell proliferation. The specificity of BN82685 towards the CDC25 phosphatases is shown by an increase in cyclin-dependent kinase 1 tyrosine 15 phosphorylation, by the reversion of the mitosis-inducing effect of CDC25B overexpression in HeLa cells, and by the lack of a growth inhibitory effect in an assay based on the use of a CDC25-independent fission yeast model. Finally, when administered p.o., BN82685 is shown to inhibit the growth of the human pancreatic tumor Mia PaCa-2 xenografted in athymic nude mice. BN82685 is therefore a promising new compound targeting CDC25, which confirms the interest of the inhibition of these enzymes as an anticancer therapeutic strategy.  相似文献   

17.
The evaluation of two automated (AutoGrouper-16C) antibody detection techniques, designed for routine use is reported. Three channels on the instrument were modified for low-ionic-strength or enzyme methods. The incidence of antibody detection was 90.5 percent, and all antibodies that were not detected had titers of 4 or less and would be unlikely to cause adverse clinical reactions if transfused. The adaptation of this automated instrument for donor antibody screening resulted in substantial time and cost savings.  相似文献   

18.
The B cell antigen receptor (BCR) is a large complex that consists of a disulfide-linked tetramer of two transmembrane heavy (mu) chains and two light (lambda or kappa) chains in association with a heterodimer of Igalpha and Igbeta. Kaposi's sarcoma-associated herpesvirus (KSHV) encodes a transforming protein called K1, which has structural and functional similarity to Igalpha and Igbeta. We demonstrate that K1 downregulates the expression of BCR complexes on the surface. The NH(2)-terminal region of K1 specifically interacts with the mu chains of BCR complexes, and this interaction retains BCR complexes in the endoplasmic reticulum, preventing their intracellular transport to the cell surface. Thus, KSHV K1 resembles Igalpha and Igbeta in its ability to induce signaling and to interact with mu chains of the BCR. However, unlike Igalpha and Igbeta, which interact with mu chains to direct BCR complexes to the cell surface, K1 interacts with mu chains to block the intracellular transport of BCR complexes to the cell surface. These results demonstrate a unique feature of the K1 transforming protein, which may confer virus-infected cells with a long-term survival advantage.  相似文献   

19.
Many Regional Blood Centers are providing AS-1(Adsol preservative) red blood cells (RBCs) as a standard product because of the extended shelf life (42 days). The use of AS-1 RBCs is concerning in neonates because of high exposure to dextrose, adenine and mannitol. We conducted this study to evaluate the safety and efficacy of AS-1 RBC use in neonates. We assigned one unit of AS-1 RBCs to each infant for small volume transfusions (15 ml/kg) for the life of the unit (42 days). The study was conducted for one year. The infants under 1500 g were included in the study. We measured the pre- and post-transfusion hematocrit, post-transfusion serum sodium, potassium, glucose, bilirubin and blood pH. We compared the average number of transfusions per patient and average blood donor exposure per patient using AS-1 RBC to CPDA-1 packed red blood cells (PRBC) use, data available for prior year. We monitored the blood transfusion reactions during the study period. The hematocrit increased significantly from 30.1 +/- 4.6 pre-transfusion to 38.3 +/- 4.9 post-transfusion. The post-transfusion serum bilirubin, blood pH, serum potassium, sodium and glucose remained within the normal range. In spite of an increase in the number of average transfusions per patient with AS-1 RBC (6.67 +/- 5.1), the average donor exposure (1.8 +/- 1.1) remained less than two donors. There were not any transfusion reactions reported during the study. In conclusion, the use of AS-1 red blood cells is safe for small volume transfusions in neonates.  相似文献   

20.
The red cell-monocyte assay (RMA), which has been used to evaluate the clinical significance of red cell (RBC) antibodies, was employed to test the effect of the dialyzable leukocyte extract (DLE) on in vitro adherence to monocytes of human RBCs coated with alloantibodies or autoantibodies. The total association index (TAI) of the RMA, expressing the number of RBCs adhering to or phagocytosed by 100 monocytes, indicated a potent inhibitory activity of DLE in the test system. TAI values of 100.4 +/- 20.1 (mean +/- SD) in the control sample, consisting of RBCs coated in vitro with anti-D, dropped to 4.0 +/- 2.1 when DLE was present in the assay medium at a concentration of 0.5 U per mL. Similar results were obtained with RBCs coated with IgG antibodies in vivo. The inhibition was dose dependent and was associated with a thermolabile component of DLE. This study establishes that DLE can modulate monocyte function by inhibiting the recognition of IgG sensitized red cells.  相似文献   

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