A trait of mind: stability and robustness of sleep across sleep opportunity manipulations during simulated military operational stress.

Study Objectives: Within-subject stability of certain sleep features across multiple nights is thought to reflect the trait-like behavior of sleep. However, to be considered a trait, a parameter must be both stable and robust. Here, we examined the stability (i.

Biochemical and biological characterization of a human Rac2 GTPase mutant associated with phagocytic immunodeficiency.

The Rho GTPase, Rac2, is expressed only in hematopoietic cell lineages, suggesting a specific cellular function in these cells. Genetic targeting studies in mice showed that Rac2 is an essential regulator of neutrophil chemotaxis, L-selectin capture and rolling, and superoxide production. Recently, a dominant negative mutation of Rac2, D57N, has been reported to be associated with a human phagocytic immunodeficiency.

Dominant negative mutation of the hematopoietic-specific Rho GTPase, Rac2, is associated with a human phagocyte immunodeficiency.

Rho GTPases control a variety of cellular processes, including actin polymerization, integrin complex formation, cell adhesion, gene transcription, cell cycle progression, and cell proliferation. A patient is described who has recurrent infections and defective neutrophil cellular functions similar to those found in Rac2-deficient mice. Molecular methods were used to clone the expressed Rac2 cDNA from this patient, and a single base pair change (G-->A at nucleotide 169) in the coding sequence was identified.

Osmometric and permeability characteristics of human placental/umbilical cord blood CD34+ cells and their application to cryopreservation.

The transplantation of placental/cord blood-derived HPC (e.g., CD34+ cells) has become a useful treatment for a broad spectrum of malignant and nonmalignant diseases.

Previous loss of chromosome 11 containing a suppressor locus increases radiosensitivity, neoplastic transformation frequency and delayed death in HeLa x fibroblast human hybrid cells.

CGL1 (HeLa x fibroblast) hybrid cells have been utilized to study mechanisms of radiation-induced neoplastic transformation of human cells in vitro. Previous analysis has shown that loss of active tumor suppressor alleles on fibroblast chromosomes 11 and 14 may be required for radiation-induced neoplastic transformation of CGL1 cells. Loss of chromosome 11 alone was, therefore, found to be necessary but not sufficient for neoplastic transformation.