Effect of gamma irradiation with 30 Gy on the coagulation system in leukoreduced fresh-frozen plasma

Impacts of leukocyte filtration and irradiation on coagulation factors in fresh frozen plasma

This study aimed to compare and analyze the changes in the coagulation factors in fresh frozen plasma (FFP) prior to and following leukocyte filtration and irradiation. In total, 30 bags of FFP from healthy donors were processed: One-third of the FFP of each bag was left within the original bag (the A group), the other two-thirds of the FFP of each bag were passed through a disposable leukocyte filter, then divided equally into two parts. One of these was designated as the B group, and the other was designated the C group (subjected to 30 Gy irradiation). All samples were analyzed to evaluate 16 coagulation indicators. Analysis of variance revealed that there were statistically significant differences in the levels of fibrinogen (FbgC) and coagulation factor VIII (FVIII:C) among the groups (P=0.044 and P=0.015, respectively); the Dunnett’s t-test revealed that there was a statistically significant difference in the level of FbgC between the A and B groups (P=0.025), and there was a statistically significant difference in the level of FVIII:C between the A and C groups (P=0.009); while the remaining 14 coagulation parameters were not significantly different among the groups. Although the levels of FbgC and FVIII:C in the FFP were reduced following treatment, this would not affect the clinical effect of the FFP.

Biological Effects of Space Radiation and Development of Effective Countermeasures

As part of a program to assess the adverse biological effects expected from astronaut exposure to space radiation, numerous different biological effects relating to astronaut health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death and extracellular matrix (ECM) remodeling), oxidative stress, gastrointestinal tract bacterial translocation and immune system activation, peripheral hematopoietic cell counts, emesis, blood coagulation, skin, behavior/fatigue (including social exploration, submaximal exercise treadmill and spontaneous locomotor activity), heart functions, alterations in biological endpoints related to astronaut vision problems (lumbar puncture/intracranial pressure, ocular ultrasound and histopathology studies), and survival, as well as long-term effects such as cancer and cataract development. A number of different countermeasures have been identified that can potentially mitigate or prevent the adverse biological effects resulting from exposure to space radiation.

Potassium content of irradiated packed red blood cells in different storage media: is there a need for additive solution-dependent recommendations for infant transfusion?

Prevention of transfusion-associated graft versus host disease (TA-GVHD) by gamma irradiation is known to induce increased K+ in supernatant of packed red blood cells (PRBCs) stored in CPDA-1 and SAGM conservative solutions. However, no data exist for PRBCs in AS-3 medium which is considered safe for neonatal transfusion. We evaluated haemolysis and K+ release from irradiated AS-3 PRBCs and compared our results with reported data for SAGM and CPDA-1 PRBCs. Our results indicate that irradiated PRBCs stored in AS-3 after more than 7 days post-irradiation should not be used in massive and/or rapidly infused transfusions in neonates and infants.

The effects of proton radiation on the prothrombin and partial thromboplastin times of irradiated ferrets

PURPOSE

To determine whether proton radiation affects coagulation.

MATERIAL AND METHODS

Ferrets were exposed to solar particle event-like proton radiation at doses of 0, 25, 100, or 200 centigray (cGy), and dose rates of 50 cGy/minute (high dose rate or HDR) or 50 cGy/hour (low dose rate or LDR). Plasma was isolated from blood collected prior to radiation exposure and at 3-7 h post-radiation. Prothrombin time (PT) assays and activated partial thromboplastin time (aPTT) assays were performed as were mixing studies to determine the coagulation factors involved.

RESULTS

HDR and LDR exposure led to statistically significant increases in PT values. It was determined that the HDR-induced increase in PT was due to Factor VII, while Factors II, V, and VII contributed to the LDR-induced increase in PT values. Only acute LDR exposure caused an increase in aPTT values, which remained elevated for 48 h post-irradiation (which was the latest time assayed in these studies). Mixing studies revealed that Factor IX contributed to the increased aPTT values. A majority of the animals exposed at the LDR had an International Normalized Ratio approaching or surpassing 2.0.

CONCLUSIONS

PT/aPTT assays resulted in increased clotting times due to different coagulation factors, indicating potential radiation-induced coagulopathy.