32 research outputs found
Cellular magnesium acquisition : an anomaly in embryonic cation homeostasis
Author Posting. © The Author(s), 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Experimental and Molecular Pathology 83 (2007): 224-240, doi:10.1016/j.yexmp.2007.03.007.The intracellular dominance of magnesium ion makes clinical assessment difficult despite the critical role of Mg++ in many key functions of cells and enzymes. There is general consensus that serum Mg++ levels are not representative of the growing number of conditions for which magnesium is known to be important. There is no consensus method or sample source for testing for clinical purposes. High intracellular Mg++ in vertebrate embryos results in part from interactions of cations which influence cell membrane transport systems. These are functionally competent from the earliest stages, at least transiently held over from the unfertilized ovum. Kinetic studies with radiotracer cations, osmolar variations, media lacking one or more of the four biological cations, Na+, Mg++, K+, and Ca++, and metabolic poison 0.05 mEq/L NaF, demonstrated: (1) all four cations influence the behavior of the others, and (2) energy is required for uptake and efflux on different time scales, some against gradient. Na+ uptake is energy dependent against an efflux gradient. The rate of K+ loss is equal with or without fluoride, suggesting a lack of an energy requirement at these stages. Ca++ efflux took twice as long in the presence of fluoride, likely due in part to intracellular binding. Mg++ is anomalous in that early teleost vertebrate embryos have an intracellular content exceeding the surrounding sea water, an isolated unaffected yolk compartment, and a clear requirement for energy for both uptake and efflux. The physiological, pathological, and therapeutic roles of magnesium are poorly understood. This will change: (1) when 28Mg is once again generally available at a reasonable cost for both basic research and clinical assessment, and (2) when serum or plasma levels are determined simultaneously with intracellular values, preferably as part of complete four cation profiles. Atomic absorption spectrophotometry, energy-dispersive x-ray analysis, and inductively coupled plasma emission spectroscopy on sublingual mucosal and peripheral blood samples are potential methods of value for coordinated assessments.AEC Grant No. 134
Contact, Continuity, and Collapse: The Norse Colonization of the North Atlantic. James H. Barrett, editor. 2003. Prepols Publishers, Turnhout, Belgium, vi + 254 pp. $142.35 (cloth), ISBN 2-503-51291-7
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The Island Chumash: Behavioral Ecology of a Maritime Society. By Douglas J. Kennett.
EVERY RUSTY NAIL IS SACRED, EVERY RUSTY NAIL IS GOOD: CONFLICT ARCHAEOLOGY, REMOTE SENSING, AND COMMUNITY ENGAGEMENT AT A NORTHWEST COAST SETTLER FORT
Site suitability modeling with culturally-specific variables: A southern Northwest Coast case study
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Return to Chetlessenten: The Antiquity and Architecture of an Athabaskan Village on the Southern Northwest Coast
Radiocarbon dates for the historic village of Chetlessenten (the Pistol River site) suggest that the numerous features and artifacts excavated by Hefiin (1966) from this Oregon coast site date primarily between about A.D. 1600 and A.D. 1856. In this paper, we summarize the historical importance of this well-known site, describe poorly documented investigations of the site by University of Oregon archaeologists between 1960 and 1961, report on architectural details for a semisubterranean wood plankhouse that may have been typical of precontact dwellings at Chetlessenten, and discuss the evidence for the antiquity of the site