Journal Articles |
Maurer-Spurej E., Pittendreigh Yakimec De Badyn C J M H; Chipperfield, K Erroneous automated optical platelet counts in 1-hour post-transfusion blood samples Journal Article International Journal of Laboratory Hematology, 32 (1), pp. e1-e8, 2008. @article{Maurer-Spurej2008, title = {Erroneous automated optical platelet counts in 1-hour post-transfusion blood samples}, author = {Maurer-Spurej, E., Pittendreigh, C., Yakimec, J., De Badyn, M. H. and Chipperfield, K.}, url = {http://onlinelibrary.wiley.com/doi/10.1111/j.1751-553X.2008.01097.x/full}, doi = {10.1111/j.1751-553X.2008.01097.x}, year = {2008}, date = {2008-08-25}, journal = {International Journal of Laboratory Hematology}, volume = {32}, number = {1}, pages = {e1-e8}, keywords = {Analyzers}, pubstate = {published}, tppubtype = {article} } |
Maurer-Spurej E., Labrie A; Brown, K Routine Quality Testing of Blood Platelet Transfusions with Dynamic Light Scattering Journal Article Particle & Particle Systems Characterization, 25 (1), pp. 99-104, 2008. Abstract | Links | Tags: Analyzers, dynamic light scattering @article{Maurer-Spurej2008b, title = {Routine Quality Testing of Blood Platelet Transfusions with Dynamic Light Scattering}, author = {Maurer-Spurej, E., Labrie, A. and Brown, K.}, url = {http://onlinelibrary.wiley.com/doi/10.1002/ppsc.200700017/pdf}, doi = {10.1002/ppsc.200700017}, year = {2008}, date = {2008-02-12}, journal = {Particle & Particle Systems Characterization}, volume = {25}, number = {1}, pages = {99-104}, abstract = {Extension of the current 5-day shelf life of platelet concentrates to increase the supply of this life saving blood product will require quality testing. However, no automated test exists to routinely measure the quality of platelet concentrates for transfusion. Platelet concentrates cannot be sampled and diluted. These practical limitations have prevented the routine use of optical methods for platelet quality testing. The Dynamic Light Scattering Platelet Monitor (DLS-PM) addresses these limitations. The DLS-PM is a portable instrument with a temperature-controlled sample holder to accommodate a wide range of sample containers. The challenges of small sample size, short light path through the sample, and accurate temperature control have been solved. The DLS-PM measures platelet size, number of platelet-derived microparticles, and the response of platelets to temperature changes, which are combined to calculate a platelet quality score. In this paper we introduce the DLS-PM and discuss the advantages and challenges for dynamic light scattering to become a clinically relevant, routinely used platelet test.}, keywords = {Analyzers, dynamic light scattering}, pubstate = {published}, tppubtype = {article} } Extension of the current 5-day shelf life of platelet concentrates to increase the supply of this life saving blood product will require quality testing. However, no automated test exists to routinely measure the quality of platelet concentrates for transfusion. Platelet concentrates cannot be sampled and diluted. These practical limitations have prevented the routine use of optical methods for platelet quality testing. The Dynamic Light Scattering Platelet Monitor (DLS-PM) addresses these limitations. The DLS-PM is a portable instrument with a temperature-controlled sample holder to accommodate a wide range of sample containers. The challenges of small sample size, short light path through the sample, and accurate temperature control have been solved. The DLS-PM measures platelet size, number of platelet-derived microparticles, and the response of platelets to temperature changes, which are combined to calculate a platelet quality score. In this paper we introduce the DLS-PM and discuss the advantages and challenges for dynamic light scattering to become a clinically relevant, routinely used platelet test. |
et al, Elisabeth Maurer-Spurej Portable dynamic light scattering instrument and method for the measurement of blood platelet suspensions Journal Article Physics in Medicine & Biology, 51 (15), pp. 3747, 2006. Abstract | Links | Tags: Analyzers, dynamic light scattering @article{Maurer-Spurej2006, title = {Portable dynamic light scattering instrument and method for the measurement of blood platelet suspensions}, author = {Elisabeth Maurer-Spurej et al }, url = {http://iopscience.iop.org/article/10.1088/0031-9155/51/15/010/meta}, doi = {10.1088/0031-9155/51/15/010}, year = {2006}, date = {2006-07-20}, journal = {Physics in Medicine & Biology}, volume = {51}, number = {15}, pages = {3747}, abstract = {No routine test exists to determine the quality of blood platelet transfusions although every year millions of patients require platelet transfusions to survive cancer chemotherapy, surgery or trauma. A new, portable dynamic light scattering instrument is described that is suitable for the measurement of turbid solutions of large particles under temperature-controlled conditions. The challenges of small sample size, short light path through the sample and accurate temperature control have been solved with a specially designed temperature-controlled sample holder for small diameter, disposable capillaries. Efficient heating and cooling is achieved with Peltier elements in direct contact with the sample capillary. Focusing optical fibres are used for light delivery and collection of scattered light. The practical use of this new technique was shown by the reproducible measurement of latex microspheres and the temperature-induced morphological changes of human blood platelets. The measured parameters for platelet transfusions are platelet size, number of platelet-derived microparticles and the response of platelets to temperature changes. This three-dimensional analysis provides a high degree of confidence for the determination of platelet quality. The experimental data are compared to a matrix and facilitate automated, unbiased quality testing.}, keywords = {Analyzers, dynamic light scattering}, pubstate = {published}, tppubtype = {article} } No routine test exists to determine the quality of blood platelet transfusions although every year millions of patients require platelet transfusions to survive cancer chemotherapy, surgery or trauma. A new, portable dynamic light scattering instrument is described that is suitable for the measurement of turbid solutions of large particles under temperature-controlled conditions. The challenges of small sample size, short light path through the sample and accurate temperature control have been solved with a specially designed temperature-controlled sample holder for small diameter, disposable capillaries. Efficient heating and cooling is achieved with Peltier elements in direct contact with the sample capillary. Focusing optical fibres are used for light delivery and collection of scattered light. The practical use of this new technique was shown by the reproducible measurement of latex microspheres and the temperature-induced morphological changes of human blood platelets. The measured parameters for platelet transfusions are platelet size, number of platelet-derived microparticles and the response of platelets to temperature changes. This three-dimensional analysis provides a high degree of confidence for the determination of platelet quality. The experimental data are compared to a matrix and facilitate automated, unbiased quality testing. |
Maurer-Spurej, Elisabeth; Devine, Dana V Platelet Aggregation Is Not Initiated by Platelet Shape Change Journal Article Laboratory Investigation, 81 (11), pp. 1517-1525, 2001. Abstract | Links | Tags: Analyzers @article{Maurer-Spurej2001, title = {Platelet Aggregation Is Not Initiated by Platelet Shape Change}, author = {Elisabeth Maurer-Spurej and Dana V Devine}, url = {https://www.nature.com/articles/3780365}, doi = {10.1038/labinvest.3780365}, year = {2001}, date = {2001-11-01}, journal = {Laboratory Investigation}, volume = {81}, number = {11}, pages = {1517-1525}, abstract = {Because the initial decrease in light transmission in platelet aggregometry is attributed to platelet shape change, it is widely held that platelet shape change is a prerequisite for platelet aggregation. We conducted this study to determine the basis of this initial optical effect in aggregometry. Platelets were activated with ADP, thrombin, or the thrombin receptor agonist peptide SFLLRN (TRAP1–6). In every case the initial decrease in light transmission occurred with the concomitant formation of microaggregates. This was also seen when preactivated platelets, which cannot undergo further morphological changes, were used, and when platelets were activated in the presence of shape-change inhibitors such as cytochalasin D and vincristine. Microscopy analysis of samples fixed at minimum light transmission in the aggregometer, which is generally assumed to signal shape change, always showed the presence of microaggregates. Microaggregation appeared to be distinct from full aggregation, as it was not inhibited by the addition of CD61, an antibody to the β3 integrin. To model these findings, fibrinogen-coated latex spheres, which cannot change shape, were aggregated with thrombin; the initial decrease in light transmission was still seen, and microaggregates formed at this time. These results indicate that platelet shape change is not a prerequisite for aggregation and that the signal widely believed to represent shape change reflects platelet microaggregation instead. We conclude that platelet aggregation occurs independently of shape change and that shape change is not necessarily followed by aggregation. These observations suggest an alternative role for platelet shape change of single platelets.}, keywords = {Analyzers}, pubstate = {published}, tppubtype = {article} } Because the initial decrease in light transmission in platelet aggregometry is attributed to platelet shape change, it is widely held that platelet shape change is a prerequisite for platelet aggregation. We conducted this study to determine the basis of this initial optical effect in aggregometry. Platelets were activated with ADP, thrombin, or the thrombin receptor agonist peptide SFLLRN (TRAP1–6). In every case the initial decrease in light transmission occurred with the concomitant formation of microaggregates. This was also seen when preactivated platelets, which cannot undergo further morphological changes, were used, and when platelets were activated in the presence of shape-change inhibitors such as cytochalasin D and vincristine. Microscopy analysis of samples fixed at minimum light transmission in the aggregometer, which is generally assumed to signal shape change, always showed the presence of microaggregates. Microaggregation appeared to be distinct from full aggregation, as it was not inhibited by the addition of CD61, an antibody to the β3 integrin. To model these findings, fibrinogen-coated latex spheres, which cannot change shape, were aggregated with thrombin; the initial decrease in light transmission was still seen, and microaggregates formed at this time. These results indicate that platelet shape change is not a prerequisite for aggregation and that the signal widely believed to represent shape change reflects platelet microaggregation instead. We conclude that platelet aggregation occurs independently of shape change and that shape change is not necessarily followed by aggregation. These observations suggest an alternative role for platelet shape change of single platelets. |
Maurer-Spurej E., Pfeiler Maurer Linder Glatter Devine G N H O D Room Temperature Activates Human Blood Platelets Journal Article Laboratory Investigation, 81 (4), pp. 581-592, 2001. Abstract | Links | Tags: Analyzers @article{Maurer-Spurej2001b, title = {Room Temperature Activates Human Blood Platelets}, author = {Maurer-Spurej, E., Pfeiler, G., Maurer, N., Linder, H., Glatter, O., Devine, D.}, url = {https://www.nature.com/articles/3780267}, doi = {10.1038/labinvest.3780267}, year = {2001}, date = {2001-04-01}, journal = {Laboratory Investigation}, volume = {81}, number = {4}, pages = {581-592}, abstract = {Temperatures ranging from room temperature (20° C) to 42° C are generally not considered to have an activating effect on platelets. However, this assumption is not supported by clinical phenomena that result in hemostatic failure related to hypothermia. In this study, we investigated the effect of temperatures between room temperature (20° C) and 42° C on human blood platelets and found that room temperature causes marked activation of platelets. Major changes in platelet morphology were seen at 20° C compared to resting platelets at 37° C. Platelet morphology was investigated with noninvasive live cell techniques (light microscopy and dynamic and static light scattering), as well as with transmission and scanning electron microscopy. The changes in platelet morphology correlated with the expression of the activation marker, activated glycoprotein (GP) IIb-IIIa, measured by flow cytometry. Twenty-five percent to 30% of platelets expressed activated GPIIb-IIIa after exposure to 20° C for 10 minutes. In the presence of serotonin re-uptake inhibitors, the serotonin content of platelets at 20° C was twice that of resting platelets. In comparison, moderate heat shock conditions (42° C for 10 minutes) caused no signs of platelet activation as indicated by the absence of morphological alterations, no expression of activated GPIIb-IIIa, and no changes in serotonin content. These results show that room temperature by itself significantly activates platelets and has an effect on the platelet serotonin content. This may contribute to both the functional lesion associated with 22° C storage of platelets for transfusion and the in vivo hemostatic failure after hypothermia.}, keywords = {Analyzers}, pubstate = {published}, tppubtype = {article} } Temperatures ranging from room temperature (20° C) to 42° C are generally not considered to have an activating effect on platelets. However, this assumption is not supported by clinical phenomena that result in hemostatic failure related to hypothermia. In this study, we investigated the effect of temperatures between room temperature (20° C) and 42° C on human blood platelets and found that room temperature causes marked activation of platelets. Major changes in platelet morphology were seen at 20° C compared to resting platelets at 37° C. Platelet morphology was investigated with noninvasive live cell techniques (light microscopy and dynamic and static light scattering), as well as with transmission and scanning electron microscopy. The changes in platelet morphology correlated with the expression of the activation marker, activated glycoprotein (GP) IIb-IIIa, measured by flow cytometry. Twenty-five percent to 30% of platelets expressed activated GPIIb-IIIa after exposure to 20° C for 10 minutes. In the presence of serotonin re-uptake inhibitors, the serotonin content of platelets at 20° C was twice that of resting platelets. In comparison, moderate heat shock conditions (42° C for 10 minutes) caused no signs of platelet activation as indicated by the absence of morphological alterations, no expression of activated GPIIb-IIIa, and no changes in serotonin content. These results show that room temperature by itself significantly activates platelets and has an effect on the platelet serotonin content. This may contribute to both the functional lesion associated with 22° C storage of platelets for transfusion and the in vivo hemostatic failure after hypothermia. |
Journal Articles |
Erroneous automated optical platelet counts in 1-hour post-transfusion blood samples Journal Article International Journal of Laboratory Hematology, 32 (1), pp. e1-e8, 2008. |
Routine Quality Testing of Blood Platelet Transfusions with Dynamic Light Scattering Journal Article Particle & Particle Systems Characterization, 25 (1), pp. 99-104, 2008. |
Portable dynamic light scattering instrument and method for the measurement of blood platelet suspensions Journal Article Physics in Medicine & Biology, 51 (15), pp. 3747, 2006. |
Platelet Aggregation Is Not Initiated by Platelet Shape Change Journal Article Laboratory Investigation, 81 (11), pp. 1517-1525, 2001. |
Room Temperature Activates Human Blood Platelets Journal Article Laboratory Investigation, 81 (4), pp. 581-592, 2001. |