Granulocyte transfusions for neutropenic patients with life-threatening infections: a single centre experience in 47 patients, who received 348 granulocyte transfusions.

INTRODUCTION: The role of granulocyte transfusions (GT) in patients with neutropenia-related infections remains controversial. MATERIALS AND METHODS: A retrospective analysis of 47 neutropenic patients, treated with 348 consecutive GTs for life-threatening infections between 1999 and 2004, is presented. RESULTS: The only grade III-IV toxicity observed in GT recipients was respiratory deterioration (n = 6, 12.8%). The overall infection-related mortality (IRM) approached 38%. Achievement of a neutrophil count of > 700 cells per microl after at least 50% of days of GTs (n = 33, 70%) significantly correlated with reduced IRM (27.3% vs. 64.3%, P < 0.02). GT doses of > 2 x 10(10) neutrophils per bag appeared to increase both neutophil and platelet counts following transfusion. CONCLUSION: GTs are safe and should be considered for patients with life-threatening neutropenic infections. However, prospective randomized studies of GTs are the only way to establish the true role of GTs.

Blood bank protocols for large-scale civilian casualty events: experience from terrorist bombing in Israel.

Terrorist attacks in crowded places cause multiple casualties that are evacuated by quick succession to nearby hospitals. The study goals were to analyse the issues of patient misidentification and excessive blood request and to develop recommendations for the management of such episodes. A retrospective analysis of nine explosion attacks was performed. In nine consecutive events, 450 casualties were reported by the National Ambulance Service, 82 of whom (18%) died on the explosion site and 368 were admitted to nearby trauma centres. Red blood cell units were typed and cross-matched for 70 patients. Seventy-three per cent of the blood supplied over the first 24 h was administered during the first 2 h. The cross-matched/transfused ratio was 2.52 +/- 1.42, reflecting the overestimation of blood requirement in mass casualty episodes. In the mass casualty setup, blood bank personnel should be alert to a potential mistransfusion or a blood collection error. Unidentified patients are subjected to errors due to only one-digit difference in their temporary identification number. Application of the system using an additional sequential four-digit number printed in bold and large size font for patients at admission reduced the possibility of misidentification. Modern technologies, including error-reduction design wristbands, barcode-based system or radiofrequency identification tags may also increase reliability of patient identification in the mass casualty setup.

A Meis family protein caudalizes neural cell fates in Xenopus.

A homologue of the Drosophila homothorax (hth) gene, Xenopus Meis3 (XMeis3), was cloned from Xenopus laevis. XMeis3 is expressed in a single stripe of cells in the early neural plate stage. By late neurula, the gene is expressed predominantly in rhombomeres two, three and four, and in the anterior spinal cord. Ectopic expression of RNA encoding XMeis3 protein causes anterior neural truncations with a concomitant expansion of hindbrain and spinal cord. Ectopic XMeis3 expression inhibits anterior neural induction in neuralized animal cap ectoderm explants without perturbing induction of pan-neural markers. In naive animal cap ectoderm, ectopic XMeis3 expression activates transcription of the posteriorly expressed neural markers, but not pan-neural markers. These results suggest that caudalizing proteins, such as XMeis3, can alter A-P patterning in the nervous system in the absence of neural induction. Regionally expressed proteins like XMeis3 could be required to overcome anterior signals and to specify posterior cell fates along the A-P axis.

Paraxial-fated mesoderm is required for neural crest induction in Xenopus embryos.

Neural crest induction is thought to occur by a two-step process. Axially fated mesoderm induces neural plate, which is then recruited to neural crest by nonneural epidermal ectoderm at the neural plate border. This model suggests a rather indirect role for mesoderm in inducing neural crest. We extensively examined the role of mesoderm in neural crest induction by determining which types of mesoderm induce neural crest cells in Xenopus embryos. We found that noggin-dorsalized ventral marginal zone (VMZ) explants differentiate as melanocytes in the absence of axial mesoderm. Dorsalized VMZ is also a potent inducer of melanocytes when juxtaposed to animal cap ectoderm in recombinant explants. Dorsalized VMZ is analogous to the dorsal-lateral marginal zone (DLMZ) region of the embryo. Neural crest-inducing activities of gastrula stage DLMZ and dorsal marginal zone (DMZ) were also compared in recombinant explants. DLMZ was a stronger inducer of neural crest than was DMZ; DLMZ induced high levels of XSlug expression and melanocyte formation in recombinants, whereas DMZ weakly induced neural crest. In whole embryos lacking DLMZ, XSlug expression and melanocyte formation were significantly reduced; in contrast, no significant reduction of XSlug expression or melanocyte formation was seen in embryos lacking a DMZ. These results suggest that paraxial-fated mesoderm plays a central role in neural crest formation by inducing a novel type of lateral neural plate. This lateral neural plate is then recruited to neural crest by adjacent nonneural epidermal ectoderm.