Abstract
Fluoride activation of the cGMP cascade of vision requires the presence of aluminum, and is shown to be mediated by the binding of one A1F-4 to the GDP/GTP-binding subunit of transducin. The presence of GDP in the site is required: A1F-4 is ineffective when the site is empty or when GDP beta S is substituted for GDP. This sensitivity to the sulfur of GDP beta S suggests that A1F-4 is in contact with the GDP. Striking structural similarities between A1F-4 and PO3-4 lead us to propose that A1F-4 mimics the role of the gamma-phosphate of GTP.
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De novo expression of the class-A macrophage scavenger receptor conferring resistance to apoptosis in differentiated human THP-1 monocytic cells.
The class-A macrophage scavenger receptor (MSR) is a trimeric multifunctional protein expressed selectively in differentiated monomyeloid phagocytes which mediates uptake of chemically modified lipoproteins and bacterial products. This study investigated whether MSR plays a role in the regulation of apoptosis, a model of genetically programmed cell death. De novo expression
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Paradoxes of fluoride toxicity
Numerous literature sources reveal evidence that fluoride affects the activities of numerous enzymes in vitro as well as in vivo. Millions of people live in endemic fluoride areas with a severe public health problem. A plethora of data suggest that fluoride should be recognized as a developmental neurotoxicant for humans.
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Fluoride: mode of action.
Conclusions and Perspectives The results obtained so far on the cellular mechanism by which fluoride may influence the growth and differentiation of osteoblastic cell lines strongly suggest alteration of one or several G protein-dependent tyrosine phosphorylation process(es), activation of the ERK, and possibly other signaling pathways. There is a controversy of
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Phosphatidylinositol 4,5-bisphosphate hydrolysis accompanies T cell receptor-induced apoptosis of murine thymocytes within the thymus.
Regulation of the development of thymocytes into mature T cells within the thymus is now known to involve antigen-induced deletion, by apoptosis, of potentially autoreactive thymocytes, and it can be mimicked either by stimulating the T cell receptor (TcR) complex by monoclonal antibody (mAb) or by ionophore-induced elevation of cytosolic
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Fluoride toxicity in the male reproductive system
This review covers the current scientific understanding of the links between environmental exposure to fluoride (F) and its known or potential effects on human male fertility. The most important consequences of these F exposures are: changes in the structure and functional behavior of spermatozoa, disruption of spermatogenesis, and disturbances of
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