Duration of red blood cell storage is associated with increased incidence of deep vein thrombosis and in hospital mortality in patients with traumatic injuries.

INTRODUCTION: In critically ill patients the relationship between the storage age of red blood cells (RBCs) transfused and outcomes are controversial. To determine if duration of RBC storage is associated with adverse outcomes we studied critically ill trauma patients requiring transfusion. METHODS: This retrospective cohort study included patients with traumatic injuries transfused >or=5 RBC units. Patients transfused >or= 1 unit of RBCs with a maximum storage age of up to 27 days were compared with those transfused 1 or more RBC units with a maximum storage age of >or= 28 days. These study groups were also matched by RBC amount (+/- 1 unit) transfused. Primary outcomes were deep vein thrombosis and in-hospital mortality. RESULTS: Two hundred and two patients were studied with 101 in both decreased and increased RBC age groups. No differences in admission vital signs, laboratory values, use of DVT prophylaxis, blood products or Injury Severity Scores were measured between study groups. In the decreased compared with increased RBC storage age groups, deep vein thrombosis occurred in 16.7% vs 34.5%, (P = 0.006), and mortality was 13.9% vs 26.7%, (P = 0.02), respectively. Patients transfused RBCs of increased storage age had an independent association with mortality, OR (95% CI), 4.0 (1.34 - 11.61), (P = 0.01), and had an increased incidence of death from multi-organ failure compared with the decreased RBC age group, 16% vs 7%, respectively, (P = 0.037). CONCLUSIONS: In trauma patients transfused >/=5 units of RBCs, transfusion of RBCs >or= 28 days of storage may be associated with deep vein thrombosis and death from multi-organ failure.

Modulation of poliovirus replicative fitness in HeLa cells by deoptimization of synonymous codon usage in the capsid region.

We replaced degenerate codons for nine amino acids within the capsid region of the Sabin type 2 oral poliovirus vaccine strain with corresponding nonpreferred synonymous codons. Codon replacements were introduced into four contiguous intervals spanning 97% of the capsid region. In the capsid region of the most highly modified virus construct, the effective number of codons used (N(C)) fell from 56.2 to 29.8, the number of CG dinucleotides rose from 97 to 302, and the G+C content increased from 48.4% to 56.4%. Replicative fitness in HeLa cells, measured by plaque areas and virus yields in single-step growth experiments, decreased in proportion to the number of replacement codons. Plaque areas decreased over an approximately 10-fold range, and virus yields decreased over an approximately 65-fold range. Perhaps unexpectedly, the synthesis and processing of viral proteins appeared to be largely unaltered by the restriction in codon usage. In contrast, total yields of viral RNA in infected cells were reduced approximately 3-fold and specific infectivities of purified virions (measured by particle/PFU ratios) decreased approximately 18-fold in the most highly modified virus. The replicative fitness of both codon replacement viruses and unmodified viruses increased with the passage number in HeLa cells. After 25 serial passages (approximately 50 replication cycles), most codon replacements were retained, and the relative fitness of the modified viruses remained well below that of the unmodified virus. The increased replicative fitness of high-passage modified virus was associated with the elimination of several CG dinucleotides. Potential applications for the systematic modulation of poliovirus replicative fitness by deoptimization of codon usage are discussed.