Using 5-color fluorescence-activated cell sorting, we isolated a subset of murine pluripotent hematopoietic stem cells (PHSC) with the phenotype Lin(-) Sca(+) kit(+) CD38(+) CD34(-) that appears to fulfill the criteria for most primitive PHSC. In the presence of whole bone marrow (BM) competitor cells, these cells produced reconstitution in lethally irradiated primary, secondary, and tertiary m...

The hierarchy of hematopoietic stem cells (HSC) is represented by several categories of maturating pluripotent progenitors. Most of them are the members of transitional cell populations and, obviously, have no capacity for self-maintenance, i. e., are not capable of giving rise to self-replicating offspring with the same proliferative potential as the parent had [1]. The foundator of this hiera...

A scheme is presented whereby pluripotent hemopoietic stem cells (PHSC) from rat bone marrow can be enriched 320-fold with the aid of the fluorescence- activated cell sorter. This scheme is based on the observations that PHSC are strongly positive for Thy-1 antigen (upper 10th percentile); have light- scattering properties (size distribution) between those of bone marrow lymphocytes and myeloid...

IL-1 has putative chemo- and radioprotective properties, but its effects on primitive hemopoietic stem cell (PHSC) and early multilineage precursor function when given with these modalities is unknown. C57BL6/J (B6) mice, given IL-1 20 h before cyclophosphamide (200 mg/kg for four biweekly doses) or before irradiation (500 cGy), were sacrificed after 4 wk. Their marrow was used as donor cells, ...

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Blood cell production is a dynamic process in which immature precursors progress through a series of developmental events that culminate in the production of mature cells of the erythroid, myeloid, and lymphoid lineages. The characteristics of cells at particular stages of development and the intrinsic and extrinsic signals that regulate their growth and differentiation are becoming increasingl...

A simple density functional theory for the various liquid-crystalline phases of parallel hard spherocylinders is formulated on the basis of Pynn's ansatz for the direct correlation function of the spherocylinders. Fair agreement with the computer simulations is found. It was Onsager [1] who showed for the first time that a nematic liquid crystalline phase can be formed, above a certain density,...

( ) A group-contribution GC method was coupled with the perturbed-hard-sphere-chain ( ) ( ) PHSC equation of state EOS to predict its characteristic parameters. This model can describe both equilibrium and ®olumetric properties of regular fluids and chain-like molecules. The estimation of group contributions for the characteristic ®olume, surface area, and interaction energy was based only on ®...

Phosphinothricin tripeptide (PTT) is a peptide antibiotic produced by Streptomyces viridochromogenes Tü494, and it is synthesized by nonribosomal peptide synthetases. The PTT biosynthetic gene cluster contains three peptide synthetase genes: phsA, phsB, and phsC. Each of these peptide synthetases comprises only one module. In neither PhsB nor PhsC is a typical C-terminal thioesterase domain pre...