Biological research focus

Much research focuses on the structures, properties, and uses of the complexes formed between d-metal ions acting as Lewis acids and a variety of Lewis bases, partly because they participate in many biological reactions. Hemoglobin and vitamin B12, for example, are both complexes—the former of iron and the latter of cobalt (Box 16.1). Complexes of the d-metals are often brightly colored and magnetic and are used in chemistry for analysis, to dissolve ions (Section 11.13), in the... 

The versatility and the robustness of CE separation in conjunction with the extreme sensitivity inherent to CL-based reactions make a combination of both techniques promising for application in a wide range of fields, including environmental analysis, biomedicine, and biological research and practice. Obviously, in comparison with other detection modes widely incorporated in CE, CL detection is a slowly evolving technique and advances should focus on the development of new detectors that are instrumentally simpler than existing systems and that offer the ability to detect various types of analytes at trace levels. 

For the biological limitation of trace metal internalisation, complex formation will invariably decrease the concentration of free metal ion and thus decrease the biouptake fluxes and carrier-bound metal (FIAM, BLM). In the case of a diffusion-limited internalisation, complex labilities and mobilities become much more pertinent when determining uptake fluxes. As shown earlier, few experiments have been designed to identify diffusion limitation of metal uptake fluxes, despite the fact that such a limitation is possible (Figure 10). Competition experiments that can distinguish a kinetic from a thermodynamic control are rare. In these areas, an important research focus is... 

Defining the biochemical mechanisms that couple stimulation at the cell surface to secretion by exocytosis is a major focus in biological research. In the mast cell, the steps by which immunologic secretagogues (for example, specific antigen, anti-IgE antibodies) activate a secretory response have been extensively studied and there are several reviews covering this area [ 12-14, 16, 121, 177],... 

The vast majority of research focused on selenium in biology (primarily in the fields of molecular biology, cell biology, and biochemistry) over the past 20 years has centered on identification and characterization of specific selenoproteins, or proteins that contain selenium in the form of selenocysteine. In addition, studies to determine the unique machinery necessary for incorporation of a nonstandard amino acid (L-selenocysteine) during translation also have been central to our understanding of how cells can utilize this metalloid. This process has been studied in bacterial models (primarily Escherichia colt) and more recently in mammals in vitro cell culture and animal models). In this work, we will review the biosynthesis of selenoproteins in bacterial systems, and only briefly review what is currently known about parallel pathways in mammals, since a comprehensive review in this area has been recently published. Moreover, we summarize the global picture of the nonspecific and specific use of selenium from a broader perspective, one that includes lesser known pathways for selenium utilization into modified nucleosides in tRNA and a labile selenium cofactor. We also review recent research on newly identified mammalian selenoproteins and discuss their role in mammalian cell biology. 

Deaza analogs of purines continue to be a major topic of interest to heterocyclic chemists, and especially those with a research focus on biological activity. The synthetic approaches divide, nearly equally, between using pyrimidines or pyrroles as precursors. 

At present the application of LA-ICP-MS in biological research and in medicine focuses on... 

The synthesis and biological evaluation of etoposide derivatives has been a primary research focus of my laboratory for many years. Some highlights of this research follow, and this work illustrates several aspects of the drug development process as described in the introduction. 

---