martindale proved that under some conditions every multiplicative isomorphism between two rings is additive. in this paper, we extend this theorem to a larger class of mappings and conclude that every multiplicative $(alpha, beta)-$derivation is additive.

This study examined the role of transforming growth factor beta 1 (TGF-beta 1) in monocytic differentiation of hematopoietic cells. TGF-beta 1 and retinoic acid (RA) inhibited HL-60 cell growth in a dose-dependent fashion. Treatment of HL-60 cells with a combination of TGF-beta 1 and a 50% optimal dose of RA (RA + TGF-beta 1) resulted in increased growth suppression compared to the individual t...

Transforming growth factor-beta (TGF-beta) has growth-stimulating effects on mesenchymal cells and several tumor cell lines. The signaling pathway for this effect is, however, not well understood. We examined how TGF-beta stimulates proliferation of MG63 human osteosarcoma cells. Two distinct type I receptors for TGF-beta, ALK-1 and ALK-5, were expressed and functional in MG63 cells. Of these t...

The identification of secreted factors that can selectively stimulate the generation of insulin producing beta-cells from stem and/or progenitor cells represent a significant step in the development of stem cell-based beta-cell replacement therapy. By elucidating the molecular mechanisms that regulate the generation of beta-cells during normal pancreatic development such putative factors may be...

Understanding and manipulating pancreatic beta-cell proliferation is a major challenge for pancreas biology and diabetes therapy. Recent studies have raised the possibility that human beta-cells can undergo dedifferentiation and give rise to highly proliferative mesenchymal cells, which retain the potential to redifferentiate into beta-cells. To directly test whether cultured beta-cells dediffe...

beta 2 glycoprotein i (β2gpi) is a single chain 50 kda highly glycosylated glycoprotein at an approximate concentration of 4 μm in cells. the abundance of this protein in plasma and its high state of preservation indicate the important role of this protein in mammalian. in addition, β2gpi has a particular structure in the fifth domain, and is categorized as the major antigen recognized by autoa...

Cellular interactions with substrata of the microenvironment are one of the major mechanisms for differentiation and morphogenesis. Many of these interactions are mediated via the beta 1 integrin subfamily of cell surface receptors, which are believed to transduce signals upon cell adhesion. We have used beta 1 integrin-deficient embryonic stem cells to test their ability to differentiate into ...