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Background: Hemophilia B is a bleeding disorder with a recessive X-linked inheritance pattern, in which the infected individuals have low levels of factor IX in their plasma. Affected individuals may have bleeding episodes after trauma or spontaneously considering the plasma level of factor IX. In order to prevent these episodes and to control bleeding, they should use coagulation factor concentrates that may be associated with the formation of inhibitors.

Methods: This study was conducted in the northeast of Iran in 2006. Among 48 individuals who agreed to participate in our survey, 3 individuals (6.25%) had used FFP, 38 s (79.16%) factor IX concentrate and 7 (14.58 both FFP and factor IX concentrate in the 6 months prior to the study. Of them, three participants (6.3%) had factor IX inhibitor which was assayed using Bethesda method.

Results: Three hemophilia B (6.3%) patients had factor IX inhibitor, but no correlation was found between the existence of the inhibitor and the type of coagulation therapy.

Conclusion: Our findings did not show any correlation between factor IX inhibitor and type of coagulation therapy used in the 6 month period (p=0.65). None of the hemophiliacs had used coagulation factor as a prophylaxis regimen and most of them (83.33%) had injected coagulation factor on demand.

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Blood transfusion centers are under considerable pressure to produce platelet concentrates with a shelf life limit of 3 to 5 days. Many approaches have been investigated experimentally to produce new hemostatically active platelet products that are capable of long term storage. In this article infusible platelet membrane will be explained as a platelet substitute versus conventional liquid-stored platelet concentrates with regard to their benefits and disadvantages in transfusion medicine. This review shows that lyophilized infusible platelet membrane as a platelet substitute might offer many important benefits over common platelet concentrates with few disadvantages. Infusible platelet membrane may have efficacy, safety and acceptable tolerability without thrombogenecity, immunogenicity or toxicity. The other main benefits of this product are improved shelf life, ease of storage, high-precision dose calculation, easy reformulation, reduced viral and bacterial load, decreased refractoriness to platelet transfusion, reduced contaminating red and white blood cells, reduced side effects due to removal of undesirable effects of intracellular and extracellular proinflamatory mediators and removal of platelet-derived microparticlecs as a source of CD40/CD40L ligands, which can enhance post-transfusion reactions, achieving hemostatic response without increasing the circulating platelet count, not being removed from circulation by immune mechanisms or sepsis and not requiring blood typing. In spite of these benefits, there are still some difficulties in demonstrating its efficacy, short-term circulation and hemostatic function. Therefore, further human clinical studies will be needed to fully define the exact role of infusible platelet membrane in the management of patients with thrombocytopenia. Keywords: Infusible platelet membrane, platelet, substitute, platelet concentrates, side effects.

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Background: Platelet preparations have been used for a wide variety of clinical applications such as hemorrhage, tissue engineering and cellular therapy. Platelet concentrates can be prepared by the apheresis method or from the whole blood using the Buffy-coat or Platelet-rich plasma methods. The purpose of this study was to compare four variations of platelet-rich plasma method based on double centrifugation protocol to identify the optimal centrifugation conditions with greatest platelet recovery and highest enrichment capacity for preparing platelet concentrates. Materials and Methods: Blood samples were obtained from 145 donors, chosen randomly from the donation department at the Tehran Blood Transfusion Center, Tehran, Iran. Four variations of platelet-rich plasma methods were selected for preparation of platelet concentrates. Platelet counting analysis was performed on samples and platelet enrichment and platelet recovery were calculated by investigating the correlation between the number of platelets in the whole blood, platelet-rich plasma and platelet concentrates. Results: Platelet count analysis revealed that the method performed with 2100 ×g for 2.30 min in the first centrifugation step and 4150 ×g for 6 min in the second centrifugation step had the highest platelet enrichment (5.59fold) and greatest platelet recovery (78.63%). Conclusion: Within the limits of this study, it can be concluded that 2100 ×g for 2.30 min in the first centrifugation step and 4150 ×g for 6 min in the second centrifugation step yielded the greatest platelet recovery and highest enrichment capacity and is a good choice for preparing platelet concentrates. Keywords: Platelet, concentrates, plasma, centrifugation, recovery, enrichment.

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Blood transfusion centers are under considerable pressure to produce platelet concentrates with high quality and safety due to the short shelf life of 3-5 days as well as possible bacterial and viral contaminations. For a variety of reasons, many Europeans have changed their methods of component production from whole blood using the North American standard platelet-rich plasma method to the buffy coat method of platelet production. Many advantages and some limitations during conversion from platelet-rich plasma method to buffy coat method have been observed. It seems that decisions to switch from platelet-rich plasma method to buffy coat method with whole blood component production should be considered the benefits from increased platelet yield, improved platelet quality, increased plasma recovery, reduced blood transfusion adverse reactions and lower pathogen transmission rates compared to the platelet-rich plasma method outweigh any transient difference in red cell parameters or inconsiderable reduction of factor VIII activity. The purpose of this review is to discuss the quality, safety and economic aspects of blood components production during conversion from platelet-rich plasma to buffy coat method in preparing blood components which may benefit developing countries.