bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced HPC recruitment in children using LVL and a new automated apheresis system
Authors: Torrabadella M. , Olivé T. , Ortega J.J. , Massuet L. 
Published: March 2003

BACKGROUND: A new automated apheresis system has recently been reported as useful in improving peripheral blood HPC collection in adults. The aim of this study has been to verify the utility of this system (AutoPBSC, COBE BCT) for standard leukapheresis and for LVL in the pediatric setting.STUDY DESIGN AND METHODS: A prospective study was set up in 29 leukapheresis procedures carried out in 26 children with malignant diseases and body weight under 40 kg who had undergone mobilization with G–CSF or with G–CSF and chemotherapy. Leukapheresis procedures were performed under two protocols, depending on the total blood volume processed: standard leukapheresis (≤3) and LVL (>3). The need to prime the tubing set with blood was determined, and the inlet flow rate, collection time, recruitment of CD34+ cells, CD34+ cell collection efficiency, component volume, leukapher‐esis cell composition, and preapheresis and postapher‐esis peripheral blood counts were measured. Paired t test, Spearman's correlation coefficient, and the Mann‐Whitney U test were employed for statistical analysis.RESULTS: Because of the low extracorporeal volume (167 mL) of the tubing set of the automated blood processor, priming was necessary in only 2 of 26 patients, both weighing under 10 kg. LVL showed better CD34+ cell yield (7.5 vs. 2.3 × 106/kg; p = 0.047), higher recruitment (2.1 vs. 0.9; p = 0.002), and greater collection efficiency (50% vs. 33%; p = 0.005) than standard leukapheresis. No significant differences were found between groups in collection time. In LVL procedures, CD34+ cell collection efficiency and recruitment were not significantly influenced by the inlet flow rate.CONCLUSION: The AutoPBSC is a reliable system for peripheral blood HPC collection in children mainly when used in combination with LVL. The major advantage of this software is a reduced need for priming. LVL allows better CD34+ cell collection efficiency, enhanced recruitment, and improved CD34+ cell yield.
Fatigue during acute isovolemic anemiain healthy, resting humans
Authors: Toy P. , Feiner J. , Viele M.K. , Watson J. , Yeap H. , Weiskopf R.B. 
Published: March 2003

BACKGROUND: Transfusion guidelines recommend that clinicians assess patients for signs and symptoms of anemia before the transfusion of RBCs. However, studies of signs and symptoms associated with acute isovolemic anemia are limited. The objective of this study was to determine whether acute reduction of Hb concentration to 5 g per dL would result in fatigue, tachycardia, or hypotension in resting, young, healthy, isovolemic humans, and whether changes were reversible with RBC transfusion.STUDY DESIGN AND METHODS: Conscious, resting, healthy adults less than 35 years old (n = 8) underwent acute isovolemic hemodilution to Hb of 5 g per dL and self‐scored their energy level at various Hb concentrations. Heart rate and blood pressure were also measured. For controls, measurements of each subject were made during a comparable period of rest without hemodilution.RESULTS: During acute isovolemic hemodilution, energy levels decreased progressively and were lower at Hb of 7, 6, and 5 g per dL than at baseline (p<0.01) or in control sessions (p<0.05). The energy level was lower at Hb 7 g per dL than at 14 ( p = 0.005), lower at Hb 6 g per dL than at 7 (p = 0.0l), and lower at Hb 5 g per dL than at 6 (p =0.01). Energy levels rose and were not different from baseline or control levels after transfusion of all autologous RBCs. Similarly, median heart rate increased with hemodilution to Hb of 7, 6, and 5 g per dL and decreased with transfusion of autologous RBCs. Supine blood pressure did not decrease with isovolemic hemodilution.CONCLUSION: In resting, young, healthy humans, acute isovolemic anemia to Hb levels of 7, 6, and 5 g per dL results in decreased self‐scored energy levels and in an increase in heart rate but not in hypotension. Changes in energy and heart rate are reversible with the transfusion of autologous RBCs.
Evaluation of automated RNA‐extraction technology and a qualitative HCV assay for sensitivity and detection of HCV RNA in pool‐screening systems
Authors: Beld M. , Habibuw M.R. , Rebers S.P.H. , Boom R. , Reesink H.W. 
Published: March 2003

BACKGROUND: The objective of this study was the evaluation of NAT technology for the detection of HCV RNA in plasma pools according to the recommendations of the Paul Ehrlich Institute (5000 IU/mL/donation) and the Committee for Proprietary Medical Products (100 IU/mL/manufacturing pool).STUDY DESIGN AND METHODS: Serial dilutions of both the EUROHEP standard (3,800 genome equivalents [geq]/mL; HCV genotype 1) and the World Health Organization (WHO) international standard (100,000 IU/mL; HCV genotype 1) were made in S/D plasma (ESPEP plasma, OctaPharma), which was nonreactive in serologic tests. Serial dilutions of plasma (2 mL) were used for extraction of HCV RNA with an automated version of a nucleic acid isolation method (NucliSens Extractor, Organon Teknika). HCV RNA was co‐extracted from 2 mL of plasma, together with 84 copies of an in vitro‐synthesized single‐strand RNA serving as internal extraction control (IC) to monitor the efficiency of extraction and PCR. Amplification and detection of both HCV RNA and IC RNA were performed with an automated PCR system and a qualitative HCV assay (COBAS Amplicor 2.0 HCV, Roche Diagnostics).RESULTS: A cutoff value of 16 geq per mL (10/10 runs [100% hit rate]) was found by using the EUROHEP standard, whereas the WHO international standard had a cutoff value of approximately 12 IU per mL (10/10 runs [100% hit rate]). The IC had a cutoff value of approximately 17.5 copies per mL (6/6 runs [100% hit rate]). Forty‐two copies per mL of IC RNA were found in 282 of 284 runs (99% hit rate). The negative controls (ESDEP plasma) were negative in all experiments. Experiments with pool sizes of 12, 24, 48, and 96 using serial dilutions of the WHO international standard revealed a cutoff value of 8 IU per mL (100% hit rate). The EUROHEP standard and the WHO international standard were detected with a 50 percent detection endpoint of 5.2 geq per mL and 1.5 IU per mL, respectively.CONCLUSION: This test system (NucliSens Extractor, and the COBAS Amplicor 2.0 HCV assay) revealed a high sensitivity for HCV RNA; considering the proposed requirements for sensitivity of NAT assays for the detection of HCV RNA in donor plasma, pool sizes of about 400 donors are possible. These endpoint results indicated that 1 IU is equal to about 3.4 geq.
WBC subset analysis of WBC‐reduced platelet components
Authors: Triulzi D.J. , Meyer E.M. , Donnenberg A.D. 
Published: March 2003

BACKGROUND: WBC‐reduced platelet components may be prepared by filtration or apheresis processing. Both methods have previously been shown to result in a residual total WBC content <5 × 106 per component. However, there may be differences in the efficacy of these techniques for removing certain WBC subsets.STUDY DESIGN AND METHODS: Two multiparameter flow cytometric assays were developed and validated to perform WBC analysis on WBC‐reduced platelets collected with two apheresis instruments (Amicus and COBE Spectra) and on 6 units of filtered pooled random‐donor platelet concentrates.RESULTS: All components contained <1 × 105 WBCs. The COBE Spectra and Amicus apheresis platelet components contained more WBCs than did filtered pooled platelets (p<0.05). Lymphocytes (T and B), monocytes, and granulocytes were identified in all components. Granulocyte content was lowest in the Amicus components and filtered pools. Monocytes were lowest in filtered pools. Amicus platelet components had fewer granulocytes and monocytes than the COBE Spectra platelets. Amicus and COBE Spectra components contained more lymphocytes than the filtered pools.CONCLUSION: Multiparameter flow cytometry can be used to quantify and characterize WBCs in WBC‐reduced platelet components. WBC reduction by filtration or apheresis was highly effective. WBCs from each subset were identified in all components. Although filtered pools had the lowest numbers of WBCs, the very low numbers observed in all components suggests that the absolute quantitative differences in WBC subset content are of questionable clinical significance.
Complications of plasma exchange in 71 consecutive patients treated for clinically suspected thrombotic thrombocytopenic purpura‐hemolytic‐uremic syndrome
Authors: Rizvi M.A. , Vesely S.K. , George J.N. , Chandler L. , Duvall D. , Smith J.W. , Gilcher R.O. 
Published: March 2003

BACKGROUND: With the increased frequency of diagnosis and improved survival of thrombotic thrombocytopenic purpura‐hemolytic‐uremic syndrome (TTP‐HUS), the morbidity of plasma exchange (PE) treatment has become more important.STUDY DESIGN AND METHODS: Data were prospectively collected on 71 consecutive patients referred to the Oklahoma Blood Institute (OBI) for PE treatment for clinically suspected TTP‐HUS from mid‐1996 to mid‐1999. Complications were defined as major or minor, and distinguished between those related to central venous catheter access or to the plasma.RESULTS: Twenty‐one patients (30%) had 27 major complications, which caused two deaths. The major complications included 2 episodes of hemorrhage after subclavian line insertion (1 death), 1 pneumothorax requiring a chest tube, 12 systemic infections (1 death), 7 episodes of catheter thrombosis requiring removal of the central venous catheter, 2 episodes of venous thrombosis requiring anticoagulant treatment, 2 episodes of hypoxemia and hypotension, and 1 episode of serum sickness. Minor complications occurred in 22 additional patients (31%). Twenty‐eight patients (39%) had no complications.CONCLUSIONS: The morbidity and mortality of catheter placement and PE are important considerations when PE treatment for clinically suspected TTP‐HUS is anticipated.
Vaccination‐associated immune hemolytic anemia in two children
Authors: Seltsam A. , Shukry‐Schulz S. , Salama A. 
Published: March 2003

BACKGROUND: Two children in whom acute autoimmune hemolytic anemia (AIHA) developed after vaccination were studied.CASE REPORTS: The children were a 20‐month‐old girl and a 21‐month‐old boy. The diagnosis of AIHA was made in accordance with established criteria (hemolysis, positive DAT, and lack of other reasons for the hemolysis). Serologic tests were performed according to standard technique.RESULTS: The girl experienced two attacks of hemolysis. The first episode occurred 2 weeks after oral polio vaccination, and the second episode was observed 7 months later, when she received a simultaneous vaccination against mumps, rubella, and measles. The DAT was strongly positive with anti‐C3d. No autoantibodies were detectable in either episode. The boy experienced acute hemolysis a few days after a simultaneous revaccination against diphtheria‐pertussis‐tetanus, Haemophilus influenzae, hepatitis B, and polio. The DAT using anti‐IgG was strongly positive, and the DAT performed with anti‐C3d was weakly positive.CONCLUSION: Vaccination‐induced AIHA resembles those forms of AIHA related to infectious diseases, and it may occur more frequently than has been reported.
Thrombopoietin and the TPO receptorduring platelet storage
Authors: Xia Y. , Li J. , Bertino A. , Kuter D.J. 
Published: March 2003

BACKGROUND: For most cells, the addition of a specific growth factor has improved cellular viability by preventing programmed cell death (apoptosis). To determine whether the platelet‐specific hematopoietic growth factor thrombopoietin (TPO) might improve platelet viability, endogenous TPO and the platelet TPO receptor were analyzed during storage, and the effect of recombinant TPO on platelet viability was assessed.STUDY DESIGN AND METHODS: During platelet storage, TPO stability was assessed by SDS‐PAGE, TPO receptor function was measured, and the platelet TPO receptor was characterized by a 125I‐rHuTPO competitive‐binding assay. A recombinant TPO, pegylated recombinant human megakaryocyte growth and development factor (PEG‐rHuMGDF), was added to platelet concentrates during storage, and its effect on pH, LDH, and metabolic activity was determined.RESULTS: During storage, the molecular weight and concentration of endogenous TPO (125 ± 19 pg/mL) and exogenous TPO (5720 ± 140 pg/mL) were constant for 12 days; the number (33 ± 4), binding affinity (149 ± 33 pM), and function of the platelet TPO receptors were constant for 7 days. Metabolic activity measured with the MTT and MTS assays closely correlated with changes in the pH and LDH. The addition of PEG‐rHuMGDF did not alter the pH, LDH, or metabolic activity of platelets during storage, but it did increase by 65 percent the uptake of 35S‐methionine into platelets. Finally, platelet concentrates obtained from donors treated with PEG‐rHuMGDF retained normal metabolic activity for 12 days, as compared with 5 to 6 days for normal platelet concentrates.CONCLUSIONS: TPO and its platelet receptor are present in normal amounts and have normal function during platelet storage. The addition of recombinant TPO increased platelet methionine transport but did not alter platelet viability during storage. Other means to prevent apoptosis during platelet storage should be considered, and the measurement of platelet metabolic activity by MTT and MTS assays may assist this effort.
An evaluation of the process and costs associated with targeted lookbacks for HCV and general notification of transfusion recipients
Authors: Callum Jeannie L. , Pinkerton Peter H. , Coovadia Ahmed S. , Thomson Anne E. , Dewsbury Frankie 
Published: March 2003

BACKGROUND: The Commission of Inquiry on the Blood System in Canada recommended that hospitals notify patients who received blood between 1978 and May 1990 of the risks of contracting HIV (up to the end of 1985 only) and HCV infection. The commission also recommended that patients should be informed of any transfusion received.STUDY DESIGN AND METHOD: General notifications for HIV and HCV for this period were begun in mid‐1994. Notification after discharge of transfusions received after May 1990 was begun in 1997. Targeted HCV lookback was performed from 1995 to 1999.RESULTS: Of 21,016 transfusion recipients from January 1978 to May 1990 identified in the general look‐back process and believed still alive, 13,549 (64%) were presumed contacted, by registered mail. The overall contact rate for the ongoing notifications (transfusions after May 1990) cannot be accurately determined, as registered mail was not used and a reply not requested. The total cost for these two processes was CAN$373,481, or $13 per patient believed contacted. Most (56%) of this cost was for the conversion to elec‐tronic form of paper transfusion records for the period 1978 through early 1984. In the targeted HCV lookback program 1995 through 1999, 94 percent of 256 recipients of specific components identified as likely to have transmitted HCV either were contacted or had died. Of 84 living recipients, 47 (56%) are HCV positive. The last documented potential serocon‐version occurred after a transfusion in November 1991, during the period of first‐generation EIA testing. If the targeted HCV lookback had been restricted to transfusions after 1987, as the FDA recommended, we would have failed to identify 39 living patients, of whom 21 are HCV positive. The cost per HCV‐positive patient notified in the targeted HCV lookback was CAN $4,174.CONCLUSION: The cost of compliance with the com‐mission's recommendations was CAN$569,636. Over 28,000 of 36,773 transfusion recipients were notified or presumed notified, and 272 targeted HCV lookbacks to 256 recipients were performed. Performance of this task required the existence of transfusion records back to 1978, conversion of paper records to electronic form, and adequate secretarial and financial support.
A model of the health and economic impact of posttransfusion hepatitis C: application to cost‐effectiveness analysis of further expansion of HCV screening protocols
Authors: Pereira Arturo , Sanz Cristina 
Published: March 2003

BACKGROUND: Cost‐effectiveness analyses are needed to decide the value of further expansion of the screening protocols for HCV in blood donors. However, such analyses are hampered by imperfect knowledge of the health and economic repercussions of posttransfu‐sion hepatitis C (PTHC).STUDY DESIGN AND METHODS: A Monte Carlo simulation of a Markov model representing the outcomes of patients transfused with HCV‐infective blood was used to estimate the health and economic impact of PTHC and to calculate the cost‐effectiveness ratio of various HCV screening methods.RESULTS: Median survival for hypothetical patients with PTHC and for controls without hepatitis was 11.25 and 11.75 years, respectively. Overall, 12.3 percent of patients receiving HCV‐infective blood will develop chronic hepatitis, 9.3 percent will progress to liver failure, and 9.25 percent will eventually die of liver disease after a median time of 20.75 years (range, 6‐70). Ninety‐one percent of the infected blood recipients had no reduction in life expectancy due to PTHC, and the average loss per patient was 0.754 years. The present value of the lifetime health costs incurred by patients with PTHC is $6330 per case. HCV antibody testing increases the patients' life expectancy by 20.4 hours per blood collection tested, and it results in net savings by decreasing the number of patients that will require treatment for liver disease in the future. Adding HCV NAT increases the patients' life expectancy by 0.08 hours per blood collection tested, at a cost‐effectiveness ratio of $1,829,611 per QALY gained.CONCLUSION: PTHC has low health benefits because of the advanced age of many blood recipients. Testing donors for HCV antibodies results in net savings for the health care system, despite low health benefits. Adding HCV NAT would produce little additional gain at a very high cost.
Immunomagnetic tumor cell selection—implications for the detection of disseminated cancer cells
Authors: Krüger William , Datta Chonda , Badbaran Anita , Tögel Florian , Gutensohn Kai , Carrero Isabel , Kröger Nicolaus , Jänicke Fritz , Zander Axel R. 
Published: March 2003

BACKGROUND: The optimal method for the detection of disseminated epithelial cancer cells has not yet been found. The standard method, using immunocytochemistry, offers a sensitivity of up to 10−6. Molecular methods such as cytokeratin‐19 RT‐PCR are about 10 times as sensitive, but they are hampered by interference such as illegitimate gene expression.STUDY DESIGN AND METHODS: Immunomagnetic bead selection of epithelial cancer cells using conjugates directed against the human epithelial antigen (HEA) followed by immunocytochemistry testing was investigated in this trial.RESULTS: No cytokeratin‐positive cells could be enriched from 56 control samples. In 104 clinical samples of bone marrow aspirations, PBPC collections, and venous blood obtained from breast cancer patients, the cytokeratin‐positive rate increased significantly, from 29.9 percent before selection to 54.8 percent after enrichment. Even the yield of detected cancer cells was significantly higher after selection. Up to 2.5 × 108 MNCs were easily processed. However, the mean cancer cell recovery after HEA enrichment was only 24.4 percent. Subsequently, selected epithelial cells were successfully immunophenotyped by use of a double‐stain technique detecting cytokeratin‐positive cells and the urokinase‐like plasminogen activator receptor.CONCLUSION: HEA bead selection in combination with the standard immunocytochemistry method is a powerful and specific tool for the detection of disseminated cancer cells without false‐positive results. Furthermore, it delivers enough cells for subsequent investigations such as characterization studies.
Receptors involved in the phagocytosis of senescent and diamide‐oxidized human RBCs
Authors: Tartakover‐Matalon Shelly , Shoham‐Kessary Hadar , Foltyn Vera , Gershon Harriet 
Published: March 2003

BACKGROUND: Senescent RBCs bear IgG and C3 opsonins that are three to four times less than required for similar phagocytosis of experimentally opsonized RBCs.STUDY DESIGN AND METHODS: Studies were performed to determine the phagocyte receptors involved in phagocytosis in vitro. The effect of clustering of opsonins and oxidative damage in the sequestration of RBCs was studied by exposing RBCs to BS3 (bis[sulfosuccinimidyl]‐suberate) and diamide (azodicarboxylic acid bis[dimethyl‐amide]).RESULTS: Sequestration of senescent RBCs was inhibited by the treatment of lymphokine‐activated monocytes with N‐acetyl‐D‐galactoseamine (GalNAc), arginine‐glycine‐aspartic acid (RGD), or antibodies to CR3, FcγRI, FcγRII, leukocyte response integrin (LRI), and integrin‐associated protein (IAP). Exposure to BS3 alone did not enhance phagocytosis. The addition of serum resulted in opsonin binding. The level of opsonization required for sequestration was higher than on senescent RBCs and was only marginally inhibited by blocking CR3, FcγRI and FcγRII. Diamide treatment alone did not lead to sequestration. Diamide‐treated RBCs exposed to serum bound opsonin much as did senescent RBCs, and sequestration was inhibited by GalNAc, RGD, and antibodies to CR3, FcγRI, FcγRII, LRI, and IAP.CONCLUSION: Membrane alterations resulting in the binding of opsonins and the sequestration of senescent RBCs may be similar to those that occur on diamide‐oxidized RBCs. They suggest the need for cooperative events among oxidation, clustering and cross‐linking, and serum opsonization.
In vitro and in vivo measurements of human RBCs frozen with glycerol and subjected to various storage temperatures before deglycerolization and storage at 4°C for 3 days
Authors: Valeri C. Robert , Pivacek Linda E. , Cassidy George P. , Ragno Gina 
Published: March 2003

BACKGROUND: This study was designed to assess the effects of changes in storage temperature of frozen RBCs such as might occur during a malfunction of the −80°C mechanical freezer or during shipment.STUDY DESIGN AND METHODS: Fifteen participants donated blood for autologous transfusion of RBCs; all RBCs were frozen with 40‐percent (wt/vol) glycerol. Five subjects received RBCs that were stored at −80°C alone before transfusion. Five subjects received RBCs that were stored initially at −80°C, then at −40°C for 4 weeks, and finally at −80°C before transfusion. Five subjects received RBCs that were stored at −80°C, then at −20°C for 2 weeks, and finally at −80°C before transfusion. After deglycerolization, the RBCs were stored at 4°C in a sodium chloride‐glucose solution for 3 days before transfusion.RESULTS: No significant differences were observed in freeze‐thaw recovery, freeze‐thaw‐wash recovery, 24‐hour posttransfusion survival, index of therapeutic effectiveness, or RBC ATP levels. Greater hemolysis and reduced RBC K+ levels were observed in the units stored at −80°C/−40°C/−80°C and in those stored at −80°C/ −20°C/−80°C compared with the units stored at −80°C alone, but these differences did not affect the 24‐hour posttransfusion survival.CONCLUSIONS: The results of this study indicated that RBCs frozen with 40‐percent (wt/vol) glycerol can be stored at −40°C for 4 weeks or at −20°C for 2 weeks between periods of frozen storage at −80°C with satisfactory results.