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71.
Time-dependent loss of surface complement regulatory activity during storage of donor blood 总被引:2,自引:0,他引:2
The survival of transfused red cells (RBCs) diminishes with time of in vitro storage in blood banks, but the molecular mechanisms underlying the slow but incessant deterioration are incompletely understood. To investigate the possibility that impaired resistance to autologous complement attack could play a role in this phenomenon, packed RBCs stored for variable periods were assayed for decay-accelerating factor (DAF) and CD59, two glycoinositol-phospholipid (GPI)-anchored, membrane- associated complement regulatory proteins that function physiologically to protect blood cells from autologous complement activation on their surfaces. Immunoradiometric and flow cytometric assays employing DAF and CD59 monoclonal antibodies showed that levels of both surface proteins gradually declined over 6 weeks. Digestion analyses with phosphatidylinositol-specific phospholipase C, an enzyme that releases GPI-anchored proteins from cell surfaces, showed that DAF and CD59 molecules with GPI anchors containing unacylated inositol were preferentially lost. These findings suggest: 1) that DAF and CD59 molecules with acylated GPI anchors are more stable in RBC membranes than are molecules with unacylated GPI anchors, and 2) that DAF and CD59 loss may participate with other membrane alterations that occur during in vitro storage in compromising the survival of transfused cells. 相似文献
72.
Histamine levels in stored platelet concentrates. Relationship to white cell content 总被引:1,自引:0,他引:1
The histamine levels in samples from platelet concentrates (PC) were measured at various storage times by a radioenzymatic assay. Elevated histamine levels were detected in 5 of 14 PC after 3 days of storage (range, less than 1 to 13.3 ng/ml) and in 9 of 14 PC after 5 days (range, less than 1 to 22.2 ng/ml). A very good linear correlation (r = 0.913) was found between the initial white cell content of the PC and the histamine level at 5 days of storage. The rise in histamine content was not influenced by the type of plastic container. The results indicate a process of histamine release by the white cells during storage. Although histamine is metabolized rapidly in vivo, a critical histamine threshold could be reached in man by the rapid infusion of stored PC containing high levels of histamine. This could explain some unexpected transfusion reactions in patients receiving PC. 相似文献
73.
DF Stroncek ; ME Clay ; ML Petzoldt ; J Smith ; W Jaszcz ; FB Oldham ; J McCullough 《Transfusion》1996,36(7):601-610
BACKGROUND: Granulocyte-colony-stimulating factor (G-CSF) has been used in patients to increase the level of circulating hematopoietic progenitors. Although G-CSF has been administered to some healthy individuals, the kinetics of mobilization of peripheral blood stem cells (PBSCs), the optimum dose schedule and the incidence and nature of adverse reactions in normal individuals are not completely defined. STUDY DESIGN AND METHODS: Normal individuals (n = 102) who received G- CSF for 5 or 10 days at doses of 2, 5, 7.5, or 10 micrograms per kg per day were studied. The subjects were observed for symptoms and physical changes, and blood samples were obtained for a variety of laboratory tests. After 5 or 10 days of G-CSF treatment, PBSCs were collected by apheresis and analyzed. RESULTS: Overall, 89 percent of the individuals completed the 5-day treatment protocol and 88 percent completed the 10- day protocol without modification of the dose of G-CSF administered. Ninety percent of donors experienced some side effect of G-CSF. The most frequent effects noted were bone pain (83%), headache (39%), body aches (23%), fatigue (14%), and nausea and/or vomiting (12%). The dose of G-CSF administered directly affected the proportion of people with bone pain (p = 0.025) or body aches (p = 0.045) or who were feeling hot or having night sweats (p = 0.02) or taking analgesics (p = 0.01). With the 5-day dose schedule, several changes in serum chemistries occurred, including increases in alkaline phosphatase (p = 0.001), alanine aminotransferase (p = 0.0013), lactate dehydrogenase (p = 0.0001), and sodium (p = 0.0001). Decreases occurred in glucose (p = 0.045), potassium (p = 0.0004), bilirubin (p = 0.001), and blood urea nitrogen (p = 0.0017). In donors who received G-CSF for 5 days, the absolute neutrophil count was increased after one G-CSF dose, and it reached a maximum on Day 6, as did the number of CD34+ cells (64.6 +/? 55.9 × 10(6) cells/L). In those same donors, the platelet count after apheresis on Day 6 was 32 +/? 13 percent lower than pretreatment values (250 +/? 42 × 10(9) cells/L). In donors receiving G-CSF for 10 days, the neutrophil count reached a maximum on Day 8, but the number of CD34+ cells peaked on Day 6 (58.3 +/? 52.1 × 10(5) cells/L) and then declined. The platelet count decreased from pretreatment values by 28 +/? 12 percent prior to apheresis on Day 11. When individuals were treated for 5 days with G-CSF, the quantity of CD34+ cells collected was directly related to the G-CSF dose. When 5 micrograms per kg per day was given, 2.80 +/? 1.81 × 10(8) cells were collected, compared with collection of 4.67 +/? 3.11 × 10(8) cells when 10 micrograms per kg per day was given (p = 0.04). More important, PBSCs collected after 10 days of G-CSF administration (5 micrograms/kg/day) had significantly fewer CD34+ cells (0.82 +/? 0.37 × 10(8) cells, p = 0.01) than did PBSCs collected after 5 days of G-CSF (5 micrograms/kg/day). CONCLUSION: Most normal donors receiving G-CSF experience side effects, but these are mild to moderate in degree. Some alterations in blood chemistries occur, but none were clinically serious. Because of the symptoms associated with G-CSF, these individuals must be monitored closely. The treatment of normal donors with G-CSF for more than 5 days significantly decreased the number of circulating CD34+ cells and the quantity collected by apheresis. 相似文献
74.
This article describes a model designed to provide an understanding of fluid flow in intravenous systems and human subjects. Experiments were developed which demonstrate that the model can represent common clinical situations. The model depicts physical devices as ideal resistors, pressure sources, and flow sources. The patient's venous system is depicted as a combination of ordinary and Starling resistors. For flows between 0 and 300 ml/hr, both physical devices and patients are adequately represented by a straight line representing the pressure-flow relationship (PFR): pressure = opening pressure + flow × resistance, where the slope is the resistance to fluid flow and the intercept is the opening pressure. The PFR for a normal vein is characterized by a flat slope (vein resistance =22±20 mm Hg/L/hr, mean ± SD) and a low intercept (opening pressure =15±8 mm Hg). The PFR for a partially obstructed vein has a resistance equal to that of an unobstructed vein and an opening pressure elevated approximately equal to the pressure obstructing the vein. For perivascular tissue, the PFR has a steep slope (tissue resistance =1,125±1,376 mm Hg/L/hr), while tissue opening pressure depends on the amount of fluid infused. At the onset of fluid extravasation (infiltration), tissue pressure usually is lower than venous pressure (8±8 versus 15±8 mm Hg), until fluid fills the distensible tissue compartment. In clinical practice, when infiltration or obstruction occurs, flow decreases and the clinician adjusts the roller clamp until correct flow resumes; no problem is obvious. The combined model for the intravenous tubing and venous systems explains the behavior of current clinical infusion devices.Presented in part at the Sixth Medical Monitoring Technology Conference, Vail, CO, March 1986; at the Annual Meeting of the American Society of Anesthesiologists, Las Vegas, NV, October 1986; at the Seventh Medical Monitoring Technology Conference, Vail, CO, March 1987; at a meeting on Computers in Critical Care and Pulmonary Medicine, San Diego, CA, June 1987; at the Annual Meeting of the American Society of Anesthesiologists, Atlanta, GA, October 1987; at the Regional Meeting of the Association for the Advancement of Medical Instrumentation, Cincinnati, OH, October 1987; at the Institute of Electrical and Electronics Engineers Ninth Annual Conference of the Engineering in Medicine and Biology Society, Boston, MA, November 1987; and at a meeting of the American Society of Hospital Pharmacists, Atlanta, GA, December 1987.Supported in part by grants from IVAC Corp.The author thanks the following individuals for important intellectual and/or technical assistance: Peter Basser, PhD, Avital Cnaan, PhD, Adriane Concus, MD, John Fox, MD, David Gissen, MD, David Joseph, MD, Anne Kamara, David Leith, MD, Leonard Lind, MD, Richard Morris, MB, BS, Barbara Orlowitz, MEE, Mary Anne Palleiko, RN, Beverly Philip, MD, Daniel Raemer, PhD, David Scott, MB, BS, John Stelling, MPH, and Marie vanRensberg, MB. At IVAC Corp: Walter Bochenko, BSEE, MBA, Robert Butterfield, BSEE, Douglas Christian, RPh, MBA, Alan Davison, BS, David Doan, PhD, Alan Somerville, BSEE, MS, Robin Wernick, BSEE, MS. 相似文献
75.
Autoantibodies against bactericidal/permeability-increasing protein in patients with cystic fibrosis 总被引:5,自引:0,他引:5
Zhao MH; Jayne DR; Ardiles LG; Culley F; Hodson ME; Lockwood CM 《QJM : monthly journal of the Association of Physicians》1996,89(4):259-265
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic
pulmonary infection/inflammation which leads to respiratory failure. The
presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has
previously been observed in the sera of patients with CF. In view of the
known relationship of ANCA with primary vasculitis and of their putative
pathogenetic role in these disorders, we studied the presence, specificity
and isotype of ANCA and their clinical associations in 66 adult CF
patients. None of the 66 CF samples had autoantibodies to the major ANCA
antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples
contained IgG and 55/66 (83%) IgA, autoantibodies to
bactericidal/permeability increasing protein (BPI), a recently
characterized ANCA specificity. All the IgA anti-BPI-positive samples were
also IgG anti-BPI-positive. The autoantibody specificity was confirmed by
inhibition assay and immunoblotting of CF sera against a neutrophil granule
preparation. Furthermore, in this cross-sectional study, anti-BPI levels
were inversely correlated with the observed reductions in FEV1 and FVC (IgA
anti-BPI and FEV1: r = 0.508, <it>p</it> < 0.0001), and
both IgG and IgA anti-BPI levels were higher in CF patients with secondary
vasculitis (<it>n</it> = 6) than in those without
(<it>p</it> < 0.05). ANCA with specificity for BPI were
present in the majority of CF sera in this study and autoimmune processes
may be associated with the development of pulmonary injury in CF.
相似文献
76.
The authors developed quantitative radioimmunoassays to allow direct measurement of total human IgG and individual IgG subclasses among antibodies bound to cell surfaces. The assays use four mouse monoclonal radioiodinated antibodies, one that reacts equally well with all four human IgG subclasses and three that are specific for human IgG subclasses 1, 2, or 3. The assays were used to analyze IgG subclass composition in 21 high-titer anti-D samples from Rh-negative volunteers immunized for Rh immunoglobulin production. Anti-D activity was restricted primarily to the IgG1 and IgG3 subclasses. Eleven of 21 sera demonstrated red cell antibodies with a marked predominance of IgG1 (87 +/- 3.6% of total IgG antibody, +/- SEM) and low levels of IgG3 (1.4 +/- 0.73%). In the remaining 10 sera, IgG3 made up a greater proportion of total IgG antibody (32 +/- 3.8%), although IgG1 was still predominant (61 +/- 4.1%). This observed dichotomy in the IgG subclass profiles of different anti-D sera may be a consideration in the selection of anti-D sera for the production of the immunoglobulin used in the prophylaxis of Rh-incompatible pregnancies. 相似文献
77.
Patrick G. Yong BSEE Leslie A. Geddes ME PhD FACC 《Journal of clinical monitoring and computing》1987,3(3):155-159
The importance of cuff deflation rate in the auscultatory method of measuring blood pressure was investigated using a computer-based model. To determine the relationship between the cuff deflation rate and the measurement error, two cuff deflation protocols were used, one based on heart rate (mm Hg per heartbeat), the other on a constant rate (mm Hg per second). The different deflation protocols and rates were tested using a constant blood pressure of 120/80 mm Hg and heart rates ranging from 40 to 120 beats/min. It was confirmed that a cuff deflation rate that is time based will introduce larger errors at low heart rates. Using heart rate as a basis for cuff deflation rate yields a constant error that is independent of heart rate. The currently used standard of 3 mm Hg/s could result in a maximum error of 2.5 mm Hg in both systolic and diastolic pressures at a heart rate of 72 beats/min. The maximum systolic and diastolic errors increase to more than 4 mm Hg at 40 beats/min. A deflation rate of 2 mm Hg/beat, however, yields a maximum error of 2 mm Hg for both systolic and diastolic pressures, independent of heart rate. A cuff deflation rate based on heart rate is recommended to help minimize changes in measurement error when measuring blood pressure if a wide range of heart rates will be encountered.Supported by grants from IVAC, San Diego, CA, and Physio Control, Redmond, WA. 相似文献
78.
Dr Nikolaus Gravenstein MD Samsun Lampotang ME Jan E. W. Beneken PhD 《Journal of clinical monitoring and computing》1985,1(1):6-10
The Bain circuit provides continuous fresh gas flow near the airway. The potential mixing of this fresh gas with expired gas may prevent reliable analysis of expired gas. We therefore investigated the interaction of sampling site, fresh gas flow rate, expiratory flow rate, and sampling flow rate on expiratory capnography. Sampling near the fresh gas outlet yielded inaccurate results under several of these conditions. The magnitude of the error was related to the fresh gas and expiratory flow rates. A reliable sampling region near the endotracheal tube was identified. 相似文献
79.
Transfusion-related acute lung injury caused by an NB2 granulocyte- specific antibody in a patient with thrombotic thrombocytopenic purpura 总被引:3,自引:0,他引:3
HLA and granulocyte-specific antibodies have been implicated in the production of transfusion-related acute lung injury (TRALI). Reported here is a case that suggests that the patient's preexisting condition may play an important role in determining whether TRALI develops upon transfusion of blood products containing anti-white cell (WBC) antibodies. A 29-year-old woman with thrombotic thrombocytopenic purpura (TTP) underwent an uneventful 1.5-volume plasma exchange, which was followed by the transfusion of 2 red cell (RBC) units. At the end of the second RBC transfusion, the patient developed clinical signs and symptoms of noncardiogenic pulmonary edema. Serologic studies demonstrated that the serum from the second RBC donor had no HLA antibodies but did have a granulocyte-specific antibody (anti-NB2) that caused the agglutination of the recipient's granulocytes, which were NB2 positive. Serum from the donor of the first RBC unit and serum from the donors of units used in the exchange had no HLA or granulocyte-specific antibodies that reacted with the recipient's WBCs. Because the donor implicated in this reaction had a history of 21 blood donations, none of which had been associated with a transfusion reaction, we suggest that the patient's preexisting condition played a significant role in this episode of TRALI, owing to the granulocyte-specific antibody. 相似文献
80.
There is abundant evidence of immune modulation induced by exposure to blood transfusions. Some studies have demonstrated a detrimental effect of transfusion on the recurrence of malignant disease and survival. We retrospectively studied the impact of blood transfusion exposure on 229 patients with breast cancer who were seen from July 1973 to September 1980, had at least 5 years' follow-up and had been randomized by therapy at the time of diagnosis. The patients were divided into four groups according to transfusion history: Group 1 (111 patients), no transfusion; Group 2 (34 patients), first transfusion after mastectomy; Group 3 (41 patients), first transfusion at mastectomy; and Group 4 (43 patients), first transfusion before mastectomy. All transfused patients received red cells or whole blood or both. At the time of analysis, 124 (54%) of the patients had died. Only Group 2 was statistically associated with decreased survival; recurrence of disease was 85 percent in this group, compared with 53 percent to 61 percent in the other three groups (p = 0.006, log-rank test). In general, Group 2 patients received transfusions because of recurrent disease. We conclude that transfusions before or at mastectomy are not associated with increased recurrence or reduced survival in patients with breast cancer. 相似文献