Regeneration Polyamines

These are the most common diazeniumdiolates, formed by the reaction of secondary amines and polyamines with nitric oxide in basic media [214, 215]. They are stable solids, capable of regenerating two equivalents of nitric oxide along with the starting amine in neutral or acidic buffers. The half-life of NO generation varies from a few seconds to many hours, depending on the amine. The decomposition to NO is a spontaneous, first-order reaction at constant pH. 

Bolto, B. A. The role of polyamine resins in thermally regenerable ion exchange, in Polymeric amines and ammonium salts, (ed.) Goethals, E. J., p. 365, New York, Pergamon Press 1980... 

The electron micrographs of no-matrix resins prepared by the precursor method show that there are discrete acidic and basic domains in which the acidic groups are in effect, embedded in a matrix of the polyamine. A possible mode of polymerization is one in which block copolymers are formed as a result of the formation, initially, of a macroradical. The marked dependence of the thermally regenerable capacity of a resin on the solvent suggests that a macroradical may be involved, since their formation and stability are also greatly dependent on the solvent. However, a study of some linear analogues suggests that this is an oversimplified picture. 

Inhibitors of DNA synthesis and cell replication are TGF-jl and HPI (= hepatic proliferation inhibitor). Their function is to block the growth-promoting factors once the nominal size of the liver has been reached. The regeneration course is, however, also linked to a complex network of biochemical processes, including the polyamines (putrescine, spermidine and spermine) as well as the precursors of nucleic acids (orotate, thymidine and uridine). (17, 33, 47-49, 55, 56)... 

Aminopropylation The transfer of decarboxylated SAMe is crucial to the synthesis of polyamines (spermine, spermidine, putresdne). Together with ornithine decarboxylase, SAMe determines the synthesis rate of polyamines, which are essential for cell regeneration. At 30 — 60 minutes, the half-fife of SAMe decarboxylase is very short and thus readily adaptable to various metabolic situations. 

H2. Hannonen, P., Raina, A., and Janne, J., Polyamine synthesis in the regenerating rat liver Stimulation of s-adenosylmethionine decarboxylase, and spermidine and spermine synthases after partial hepatectmny. Biochim. Biophys. Acta 273,... 

Goeppert A, Czaim M, May RB, Prakash GKS, Olah GA, Narayanan SR (2011) Carbon dioxide capture from the air using a polyamine based regenerable solid adsorbent. J Am Chem Soc 133 20164-20167... 

Besides tbe CO2/N2 selectivity and the CO2 uptake capacity, cyclability is another important factor in post-combustion CO2 capture. TSA and VSA are combined to test the cyclability of the polyamine-tethered PAFs. After 20 cycles, no capacity loss can be observed (Fig. 4.10). Although regeneration energy for PPN-6-CH2DETA with more primary amines species in the network are higher than those for mmen-CuBTTri [82] with only secondary amines, it is still lower than that for amine solution. 

F7 Fausto, N., Brandt, J. T. and Kesner, L. Possible interactions between the urea cycle and synthesis of pyrimidines and polyamines in regenerating liver. Cancer Res., 35, 397-404 (1975)... 

The dithiocarbamate-type ligand produced from the reaction of carbon disulfide with silica-polyamine composites represents a viable alternative to the previously reported ethylene-sulfide-modified composites. This material should prove useful for immobilizing mercury that is contained in aqueous waste streams. The resin is not going to be useful for applications requiring the regeneration and reuse of the resin. There are several other polystyrene and silica-based mercury removal resins available on the market, and it remains to be shown how these resins compare with WP-3. 

The alkaline regeneration affects polyethylene-polyamine ion exchangers even more (Figure 11). The alkali causes a sequence if reactions transforming original pyridine groups of this ion exchanger to pyridone ... 

A number of early studies on plant polyamines have docnmented that increased biosynthesis of polyamines is associated with the growth, regeneration, and responses to external environmental stimuli of plants (Flores and Galston 1982 Evans and Malmberg 1989 Galston and Sawhney 1990 Kumar et al. 1997). Detailed information on plant polyamine physiology and biochemistry has previously been... 

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