Promoting agent

Phorbol esters are promoters that interact with cellular receptors and activate protein kinase C. Usually protein kinase C is activated by Ca++ and diacylglycerol, both of which result from the hydrolysis of phosphoinositides catalyzed by phospholipase C. Phospholipase C is normally activated by several different growth factors. Thus phorbol esters bypass a tightly regulated step in the control of cell growth. Since protein kinase C phosphorylates various proteins, it is not known how this activity participates in establishing a cancerous line of cells. 

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Nonmedical uses claimed for pyridopyridazines include fungicides, growth promotion agents, parasiticides, UV absorbants and dyestuff intermediates. 

Dichloro monomers can also be polymerized with bisphenols in the presence of fluorides as promoting agents.78 The fluoride ions promote the displacement of the chloride sites to form more reactive fluoride sites, which react with phenolate anion to form high-molecular-weight polymers. Adding 5-10 mol % phase transfer catalysts such as A-alkyl-4-(dialkylamino)pyridium chlorides significantly increased the nucleophilicity and solubility of phenoxide anion and thus shortened the reaction time to one fifth of the uncatalyzed reaction to achieve the same molecular weight.79... 

Carbohydrate-coupling or glycosylation, is a major synthesis method in carbohydrate preparation. Silver silicates and Ag(I)-exchanged zeolite A - so-called insoluble Ag(I) - have been advocated as promoting agents, applied in more than stoichiometric amount (Fig. 9). All hydroxyl groups except the attacking one are suitably protected. 

In view of the accessibility of zeolite A (only linear molecules adsorb) the coupling will take place at the outer surface of the zeolite crystals. Indeed, Ag-Y and especially a Ag-loaded amorphous silica-alumina, containing a spectrum of wider pores, mrned out to be much better promoter-agents (ref. 28). The silica-alumina is etched with aqueous NaOH and subsequently exchanged with Ag(I). 

From bark, valuable chemicals, such as betulinol, can be obtained [5]. Betulinol is used as a health-promoting agent. Recently Holmbom et al. [27, 28] discovered that hydroxymatairesinol (HMR) is concentrated in the stems and knots of Norway spruce Picea abies). It can be extracted and transformed catalytically to matairesinol (MAT), which is an antioxidant and anticarcinogenic agent [29-31]. 

Cramer SC, Koroshetz WJ, Einklestein SR The case for modality-specific outcome measures in clinical trials of stroke recovery-promoting agents. Stroke 2007 38 1393-1395. 

Several chemicals can act as initiators and/or promoting agents participating actively in the process of carcinogenesis and also producing synergistic effects when taken simultaneously via multiple routes of exposure. 

Engber T. M., Koury E. J., Dennis S. A. et al. (1998). Differential patterns of regional c-Fos induction in the rat brain by amphetamine and the novel wakefulness-promoting agent modafinil. Neurosci. Lett. 241, 95-8. 

BH3 acts both as a reducing agent for the acyl carbonyl and as a promoting agent for subsequent CO insertion into the metal-alkyl bond. As yet the process has been carried as far as C Hg, with Mn(CO)5(CH3), CO, and I B THF as reactants. 

Under basal conditions, PKC is predominantly a cytoplasmic protein. Upon activation by Ca2+ or DAG, the enzyme associates with the plasma membrane, the site of many of its known physiological substrates, including receptors and ion channels. In fact, the translocation of PKC from the cytoplasm to the membrane has long been used as an experimental measure of enzyme activation. Such translocation has often been assayed by phorbol ester binding phorbol esters are tumor-promoting agents that selectively bind to and activate PKC. The molecular basis of the translocation of PKC from the cytoplasm to the plasma membrane has been solved. Subsequent to activation, PKC binds with high affinity to a series of membrane-associated proteins, termed receptors for... 

Interaction effects of arsenic with other carcinogens, cocarcinogens, promoting agents, inhibitors, and common environmental contaminants... 

Van Duuren BL, Goldschmidt BM. 1976. Cocarcinogenic and tumor promoting agents in tobacco carcinogenesis. J Natl Cancer Inst 56 1237-1242. 

Uses. In catalysis with and without promoting agents fumigant flux for soldering magnesium... 

Schlatterer K, Krauter G, Schlatterer B, Hecker E, Chandra P (1999) A novel protein (plO) induced by 12-0-tetradecanoyl-phorbol-13-acetate (TPA) and other hy-perplasiogenic tumor-promoting and non-promoting agents in murine epidermis. Anticancer Res 19 397-404... 

Yoshida, and S. Mizusaki. Identification of cembratriene-4,6-diol as anti-tumor-promoting agent from cigarette smoke condensate. Carcinogenesis... 

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