The Experts below are selected from a list of 45 Experts worldwide ranked by ideXlab platform
Nancy M Heddle - One of the best experts on this subject based on the ideXlab platform.
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a randomized controlled trial comparing the frequency of acute reactions to Plasma removed platelets and prestorage wbc reduced platelets
Transfusion, 2002Co-Authors: Nancy M Heddle, Ralph M Meyer, Irwin Walker, Robin S Roberts, Morris A Blajchman, Jeffrey H Lipton, Graham Sher, Lorrie A Constantini, Bruce Patterson, Kevin E ThorpeAbstract:BACKGROUND: Removal of the Plasma Supernatant from platelets before transfusion is effective in preventing acute reactions to platelets caused by cytokines. Prestorage WBC reduction of platelets may be even more effective at preventing reactions as the WBCs are removed and WBC-derived cytokines do not accumulate in this component. This study evaluates the effectiveness of Plasma removal and two methods of prestorage WBC reduction for preventing acute reactions to platelets. STUDY DESIGN AND METHODS: Platelets given to adults with hematologic malignancies were randomly allocated to one of three types: Plasma Supernatant removed and a platelet storage solution added, whole blood-derived platelets that are prestorage WBC reduced by filtration before storage, and prestorage WBC-reduced apheresis platelets. Patients were monitored before, during, and after transfusion, and the severity of reactions was graded on a Likert scale. RESULTS: A total of 129 patients from four centers were given 1190 platelet transfusions. The overall frequency of reactions was 13.6 percent (162 of 1190), 21.3 percent (36 of 169) for the Plasma-removed platelets, 11.4 percent (59 of 517) for random donor WBC-reduced platelets, and 13.3 percent (67 of 504) for apheresis WBC-reduced platelets (p = 0.384). The overall frequency of severe reactions was 4.1 percent with Plasma-removed platelets, 1.7 percent for whole blood-derived, prestorage WBC-reduced platelets, and 1.4 percent for prestorage WBC-reduced apheresis platelets. CONCLUSION: The frequency of reactions to Plasma-removed platelets and prestorage WBC-reduced platelets was not significantly different; however, the power of the study for this comparison was low. There was no difference in the frequency of reactions to the two types of prestorage WBC-reduced platelets. The frequency of severe reactions to prestorage WBC-reduced platelets is low, occurring in only 1 to 2 percent of transfusions.
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a randomized controlled trial comparing Plasma removal with white cell reduction to prevent reactions to platelets
Transfusion, 1999Co-Authors: Nancy M Heddle, Luba Klama, Ralph M Meyer, Irwin Walker, Lynn K Boshkov, Robin S Roberts, Shelley Chambers, Linda Podlosky, Pamela Ohoski, Mark LevineAbstract:BACKGROUND: Recent data suggest that most reactions to platelets are caused by white cell (WBC)-derived cytokines that accumulate in the Plasma portion of the component during storage. On the basis of this theory, the effectiveness of two interventions to prevent reactions, poststorage WBC reduction and Plasma depletion, were compared. STUDY DESIGN: A multiple crossover design was used, in which platelet components for transfusion to a patient randomly were WBC reduced after storage, or the Plasma Supernatant was removed. Adults >17 years of age, with a hematologic disease requiring platelet transfusion support, were eligible for the study. Patients were assessed for signs and symptoms characteristic of a reaction during, immediately after, and 1 hour after transfusion. Reactions were graded as mild, moderate, or severe. Interleukin 6 levels were also measured in the transfused platelet components. RESULTS: There were 380 analyzable platelet transfusions to 30 patients. The frequency of reactions was 25.8 percent (48/186) in the transfusions of poststorage WBC-reduced platelets and 17.0 percent (33/194) in the transfusions of Plasma-depleted platelets (p<0.008). The severity of the reaction was graded by the patient. Severe reactions occurred more frequently in connection with poststorage WBC-reduced platelets than with Plasma-depleted platelets: 33.4 percent (16/48) versus 18.2 percent (6/33), respectively (p = 0.048). Regression analysis identified interleukin 6 as the most significant of the evaluated factors in its correlation with the risk of reaction. CONCLUSION: Plasma removal is more effective than poststorage WBC reduction in preventing reactions, especially severe reactions to platelets.
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the role of the Plasma from platelet concentrates in transfusion reactions
The New England Journal of Medicine, 1994Co-Authors: Nancy M Heddle, Luba Klama, Irwin Walker, Joel Singer, Carl D Richards, Paul W M Fedak, John G KeltonAbstract:Background Febrile, nonhemolytic transfusion reactions are the most frequent adverse reactions to platelets. A number of observations argue against the widely held view that these reactions result from the interaction between antileukocyte antibodies in the recipient and leukocytes in the platelet product. We sought to determine whether substances in the Plasma or the cells in the product cause reactions to transfused platelets. Methods We separated standard platelet concentrates into their Plasma and cellular components and then transfused both portions in random order. Patients were monitored for reactions during all transfusions. Before each transfusion, the concentration of cytokines (interleukin-1β and interleukin-6) was measured in the platelet products. Studies were also performed on the platelet products to determine the effect of storage on the concentration of cytokines. Results Sixty-four pairs of platelet-product components (the Plasma Supernatant and the cells) were administered to 12 patient...
Irwin Walker - One of the best experts on this subject based on the ideXlab platform.
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a randomized controlled trial comparing the frequency of acute reactions to Plasma removed platelets and prestorage wbc reduced platelets
Transfusion, 2002Co-Authors: Nancy M Heddle, Ralph M Meyer, Irwin Walker, Robin S Roberts, Morris A Blajchman, Jeffrey H Lipton, Graham Sher, Lorrie A Constantini, Bruce Patterson, Kevin E ThorpeAbstract:BACKGROUND: Removal of the Plasma Supernatant from platelets before transfusion is effective in preventing acute reactions to platelets caused by cytokines. Prestorage WBC reduction of platelets may be even more effective at preventing reactions as the WBCs are removed and WBC-derived cytokines do not accumulate in this component. This study evaluates the effectiveness of Plasma removal and two methods of prestorage WBC reduction for preventing acute reactions to platelets. STUDY DESIGN AND METHODS: Platelets given to adults with hematologic malignancies were randomly allocated to one of three types: Plasma Supernatant removed and a platelet storage solution added, whole blood-derived platelets that are prestorage WBC reduced by filtration before storage, and prestorage WBC-reduced apheresis platelets. Patients were monitored before, during, and after transfusion, and the severity of reactions was graded on a Likert scale. RESULTS: A total of 129 patients from four centers were given 1190 platelet transfusions. The overall frequency of reactions was 13.6 percent (162 of 1190), 21.3 percent (36 of 169) for the Plasma-removed platelets, 11.4 percent (59 of 517) for random donor WBC-reduced platelets, and 13.3 percent (67 of 504) for apheresis WBC-reduced platelets (p = 0.384). The overall frequency of severe reactions was 4.1 percent with Plasma-removed platelets, 1.7 percent for whole blood-derived, prestorage WBC-reduced platelets, and 1.4 percent for prestorage WBC-reduced apheresis platelets. CONCLUSION: The frequency of reactions to Plasma-removed platelets and prestorage WBC-reduced platelets was not significantly different; however, the power of the study for this comparison was low. There was no difference in the frequency of reactions to the two types of prestorage WBC-reduced platelets. The frequency of severe reactions to prestorage WBC-reduced platelets is low, occurring in only 1 to 2 percent of transfusions.
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a randomized controlled trial comparing Plasma removal with white cell reduction to prevent reactions to platelets
Transfusion, 1999Co-Authors: Nancy M Heddle, Luba Klama, Ralph M Meyer, Irwin Walker, Lynn K Boshkov, Robin S Roberts, Shelley Chambers, Linda Podlosky, Pamela Ohoski, Mark LevineAbstract:BACKGROUND: Recent data suggest that most reactions to platelets are caused by white cell (WBC)-derived cytokines that accumulate in the Plasma portion of the component during storage. On the basis of this theory, the effectiveness of two interventions to prevent reactions, poststorage WBC reduction and Plasma depletion, were compared. STUDY DESIGN: A multiple crossover design was used, in which platelet components for transfusion to a patient randomly were WBC reduced after storage, or the Plasma Supernatant was removed. Adults >17 years of age, with a hematologic disease requiring platelet transfusion support, were eligible for the study. Patients were assessed for signs and symptoms characteristic of a reaction during, immediately after, and 1 hour after transfusion. Reactions were graded as mild, moderate, or severe. Interleukin 6 levels were also measured in the transfused platelet components. RESULTS: There were 380 analyzable platelet transfusions to 30 patients. The frequency of reactions was 25.8 percent (48/186) in the transfusions of poststorage WBC-reduced platelets and 17.0 percent (33/194) in the transfusions of Plasma-depleted platelets (p<0.008). The severity of the reaction was graded by the patient. Severe reactions occurred more frequently in connection with poststorage WBC-reduced platelets than with Plasma-depleted platelets: 33.4 percent (16/48) versus 18.2 percent (6/33), respectively (p = 0.048). Regression analysis identified interleukin 6 as the most significant of the evaluated factors in its correlation with the risk of reaction. CONCLUSION: Plasma removal is more effective than poststorage WBC reduction in preventing reactions, especially severe reactions to platelets.
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the role of the Plasma from platelet concentrates in transfusion reactions
The New England Journal of Medicine, 1994Co-Authors: Nancy M Heddle, Luba Klama, Irwin Walker, Joel Singer, Carl D Richards, Paul W M Fedak, John G KeltonAbstract:Background Febrile, nonhemolytic transfusion reactions are the most frequent adverse reactions to platelets. A number of observations argue against the widely held view that these reactions result from the interaction between antileukocyte antibodies in the recipient and leukocytes in the platelet product. We sought to determine whether substances in the Plasma or the cells in the product cause reactions to transfused platelets. Methods We separated standard platelet concentrates into their Plasma and cellular components and then transfused both portions in random order. Patients were monitored for reactions during all transfusions. Before each transfusion, the concentration of cytokines (interleukin-1β and interleukin-6) was measured in the platelet products. Studies were also performed on the platelet products to determine the effect of storage on the concentration of cytokines. Results Sixty-four pairs of platelet-product components (the Plasma Supernatant and the cells) were administered to 12 patient...
Bruno Gogly - One of the best experts on this subject based on the ideXlab platform.
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platelet rich fibrin prf a second generation platelet concentrate part iii leucocyte activation a new feature for platelet concentrates
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2006Co-Authors: D Dohan, Joseph Choukroun, Antoine Diss, Steve L Dohan, Anthony Dohan, Jaafar Mouhyi, Bruno GoglyAbstract:Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. In this third article, we investigate the immune features of this biomaterial. During PRF processing, leucocytes could also secrete cytokines in reaction to the hemostatic and inflammatory phenomena artificially induced in the centrifuged tube. We therefore undertook to quantify 5 significant cell mediators within platelet poor Plasma Supernatant and PRF clot exudate serum: 3 proinflammatory cytokines (IL-1β, IL-6, and TNF-α), an antiinflammatory cytokine (IL-4), and a key growth promoter of angiogenesis (VEGF). Our data are correlated with that obtained in Plasma (nonactivated blood) and in sera (activated blood). These initial analyses revealed that PRF could be an immune regulation node with inflammation retrocontrol abilities. This concept could explain the reduction of postoperative infections when PRF is used as surgical additive.
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platelet rich fibrin prf a second generation platelet concentrate part ii platelet related biologic features
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2006Co-Authors: D Dohan, Joseph Choukroun, Antoine Diss, Steve L Dohan, Anthony Dohan, Jaafar Mouhyi, Bruno GoglyAbstract:Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. In this second article, we investigate the platelet-associated features of this biomaterial. During PRF processing by centrifugation, platelets are activated and their massive degranulation implies a very significant cytokine release. Concentrated platelet-rich Plasma platelet cytokines have already been quantified in many technologic configurations. To carry out a comparative study, we therefore undertook to quantify PDGF-BB, TGFβ-1, and IGF-I within PPP (platelet-poor Plasma) Supernatant and PRF clot exudate serum. These initial analyses revealed that slow fibrin polymerization during PRF processing leads to the intrinsic incorporation of platelet cytokines and glycanic chains in the fibrin meshes. This result would imply that PRF, unlike the other platelet concentrates, would be able to progressively release cytokines during fibrin matrix remodeling; such a mechanism might explain the clinically observed healing properties of PRF.
Mark Levine - One of the best experts on this subject based on the ideXlab platform.
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a randomized controlled trial comparing Plasma removal with white cell reduction to prevent reactions to platelets
Transfusion, 1999Co-Authors: Nancy M Heddle, Luba Klama, Ralph M Meyer, Irwin Walker, Lynn K Boshkov, Robin S Roberts, Shelley Chambers, Linda Podlosky, Pamela Ohoski, Mark LevineAbstract:BACKGROUND: Recent data suggest that most reactions to platelets are caused by white cell (WBC)-derived cytokines that accumulate in the Plasma portion of the component during storage. On the basis of this theory, the effectiveness of two interventions to prevent reactions, poststorage WBC reduction and Plasma depletion, were compared. STUDY DESIGN: A multiple crossover design was used, in which platelet components for transfusion to a patient randomly were WBC reduced after storage, or the Plasma Supernatant was removed. Adults >17 years of age, with a hematologic disease requiring platelet transfusion support, were eligible for the study. Patients were assessed for signs and symptoms characteristic of a reaction during, immediately after, and 1 hour after transfusion. Reactions were graded as mild, moderate, or severe. Interleukin 6 levels were also measured in the transfused platelet components. RESULTS: There were 380 analyzable platelet transfusions to 30 patients. The frequency of reactions was 25.8 percent (48/186) in the transfusions of poststorage WBC-reduced platelets and 17.0 percent (33/194) in the transfusions of Plasma-depleted platelets (p<0.008). The severity of the reaction was graded by the patient. Severe reactions occurred more frequently in connection with poststorage WBC-reduced platelets than with Plasma-depleted platelets: 33.4 percent (16/48) versus 18.2 percent (6/33), respectively (p = 0.048). Regression analysis identified interleukin 6 as the most significant of the evaluated factors in its correlation with the risk of reaction. CONCLUSION: Plasma removal is more effective than poststorage WBC reduction in preventing reactions, especially severe reactions to platelets.
Ralph M Meyer - One of the best experts on this subject based on the ideXlab platform.
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a randomized controlled trial comparing the frequency of acute reactions to Plasma removed platelets and prestorage wbc reduced platelets
Transfusion, 2002Co-Authors: Nancy M Heddle, Ralph M Meyer, Irwin Walker, Robin S Roberts, Morris A Blajchman, Jeffrey H Lipton, Graham Sher, Lorrie A Constantini, Bruce Patterson, Kevin E ThorpeAbstract:BACKGROUND: Removal of the Plasma Supernatant from platelets before transfusion is effective in preventing acute reactions to platelets caused by cytokines. Prestorage WBC reduction of platelets may be even more effective at preventing reactions as the WBCs are removed and WBC-derived cytokines do not accumulate in this component. This study evaluates the effectiveness of Plasma removal and two methods of prestorage WBC reduction for preventing acute reactions to platelets. STUDY DESIGN AND METHODS: Platelets given to adults with hematologic malignancies were randomly allocated to one of three types: Plasma Supernatant removed and a platelet storage solution added, whole blood-derived platelets that are prestorage WBC reduced by filtration before storage, and prestorage WBC-reduced apheresis platelets. Patients were monitored before, during, and after transfusion, and the severity of reactions was graded on a Likert scale. RESULTS: A total of 129 patients from four centers were given 1190 platelet transfusions. The overall frequency of reactions was 13.6 percent (162 of 1190), 21.3 percent (36 of 169) for the Plasma-removed platelets, 11.4 percent (59 of 517) for random donor WBC-reduced platelets, and 13.3 percent (67 of 504) for apheresis WBC-reduced platelets (p = 0.384). The overall frequency of severe reactions was 4.1 percent with Plasma-removed platelets, 1.7 percent for whole blood-derived, prestorage WBC-reduced platelets, and 1.4 percent for prestorage WBC-reduced apheresis platelets. CONCLUSION: The frequency of reactions to Plasma-removed platelets and prestorage WBC-reduced platelets was not significantly different; however, the power of the study for this comparison was low. There was no difference in the frequency of reactions to the two types of prestorage WBC-reduced platelets. The frequency of severe reactions to prestorage WBC-reduced platelets is low, occurring in only 1 to 2 percent of transfusions.
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a randomized controlled trial comparing Plasma removal with white cell reduction to prevent reactions to platelets
Transfusion, 1999Co-Authors: Nancy M Heddle, Luba Klama, Ralph M Meyer, Irwin Walker, Lynn K Boshkov, Robin S Roberts, Shelley Chambers, Linda Podlosky, Pamela Ohoski, Mark LevineAbstract:BACKGROUND: Recent data suggest that most reactions to platelets are caused by white cell (WBC)-derived cytokines that accumulate in the Plasma portion of the component during storage. On the basis of this theory, the effectiveness of two interventions to prevent reactions, poststorage WBC reduction and Plasma depletion, were compared. STUDY DESIGN: A multiple crossover design was used, in which platelet components for transfusion to a patient randomly were WBC reduced after storage, or the Plasma Supernatant was removed. Adults >17 years of age, with a hematologic disease requiring platelet transfusion support, were eligible for the study. Patients were assessed for signs and symptoms characteristic of a reaction during, immediately after, and 1 hour after transfusion. Reactions were graded as mild, moderate, or severe. Interleukin 6 levels were also measured in the transfused platelet components. RESULTS: There were 380 analyzable platelet transfusions to 30 patients. The frequency of reactions was 25.8 percent (48/186) in the transfusions of poststorage WBC-reduced platelets and 17.0 percent (33/194) in the transfusions of Plasma-depleted platelets (p<0.008). The severity of the reaction was graded by the patient. Severe reactions occurred more frequently in connection with poststorage WBC-reduced platelets than with Plasma-depleted platelets: 33.4 percent (16/48) versus 18.2 percent (6/33), respectively (p = 0.048). Regression analysis identified interleukin 6 as the most significant of the evaluated factors in its correlation with the risk of reaction. CONCLUSION: Plasma removal is more effective than poststorage WBC reduction in preventing reactions, especially severe reactions to platelets.