Agent stabilizing

There are quite a few quinidine-like agents that are used frequently as membrane-stabilizing drugs. For instanee 

Conversion of 4-diisopropylamino-2-phenyl-2-(2-pyridyl) butyronitrile to the corresponding amide is caused by heating with concentrated sulphuric acid which on treatment with phosphoric acid yields the official compound disopyramide phosphate. 

Disopyramide phosphate is recommended orally as a prophylaxis of either unifocal or multifocal premature ventricular contractions and ventricular tachycardia. It also exhibits both anticholinergic and local anaesthetic properties. 

Dose Initial, adult, oral, 200 to 300 mg followed by 100 to 200 mg after every 6 hours. 

4 -Chloro-N-(l-isopropyl-4-piperidinyl)-2-phenyl-acetanilide monohydrochloride Benzeneacetamide, N-(4-chlorophenyl)-N-l-(l-methylethyl)-4-piperidinyl-, monohydrochloride Lorcainide Hydrochloride (Janssen Pharmaceutica, Belgium) 

Many food colloids are stabilized from proteins from milk or eggs [817]. Milk and cream, for example, are stabilized by milk proteins, such as casein micelles, which form a membrane around the oil (fat) droplets [817]. Mayonnaise, hollandaise, and bearnaise, for example, are O/W emulsions mainly stabilized by egg-yolk protein, which is a mixture of lipids (including lecithin), proteins, and lipoproteins [811,817]. The protein-covered oil (fat) droplets are stabilized by a combination of electrostatic and steric stabilization [817]. Alcohols may also be added, such as glycerol, propylene glycol, sorbitol, or sucrose sometimes these are modified by esterification or by 

Most of the surfactants used to stabilize food emulsions and foams fall into two categories [293,803,814,820]  

The high molar mass species reside mostly in the aqueous phase with a number of peptide groups residing in the oil/water interface [293]. Although these latter surfactants are less effective at reducing interfacial tension, they can form a viscoelastic membrane-like film around oil droplets or air bubbles. These tend to be used in the preparation of, for example, O/W emulsions. These trends are by no means exclusive, mixtures are the norm and competitive adsorption is prevalent. Caseinate, one of the most commonly used surfactants in the food industry, is itself a mixture of interacting proteins of varying surface activity [814], 

There are also several water-soluble mixtures of polysaccharides, including those derived from seaweeds and marine animals, such as gum arabic, agar, algin, carrageenan, and chitin. These are hydrophilic. Their suspensions in water can be quite viscous and can readily form gels, and they can form viscous interfacial films around dispersed droplets and bubbles [821], They are used to stabilize suspensions, foams, and emulsions and are used in many different foods and medicines including, for example, ice cream [428,430], See also Ref. [822], 

1) Mono- and diglycerides are derived from partial hydrolysis of animal or vegetable fats. 

Many food colloids are stabilized of proteins from milk or eggs [19]. Milk and cream, for example, are stabilized by milk proteins, such as casein micelles, which form a membrane around the oil (fat) droplets [19]. Mayonnaise, hollandaise and bearnaise, for example, are O/W emulsions mainly stabilized by egg yolk protein. 

The protein-covered oil (fat) droplets are stabilized by a combination of electrostatic and steric stabilization [19]. Alcohols may also be added, such as glycerol, propylene glycol, sorbitol or sucrose sometimes these are modified by esterification or by reacting them with ethylene oxide [1]. There are several reviews of food emulsifiers [1, 20-22]. 

W/O emulsions. Monoglycerides form lamellar phases bilayers separated by aqueous layers. These lipid bilayers can improve the texture of fat-free foods such as spreads, dressings and baked products and when sufficiently cooled they can gel [20]. 

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Properties of PSZ depend on whether CaO, MgO, or Y2O2 is used as the stabilizing agent. 

Geotextiles may be woven, nonwoven, or knitted. AH types, woven, nonwoven, or knitted, are susceptible to degradation owing to the effects of ultraviolet light and water. Thus stabilizing agents are added to the base polymeric material to lessen the effects of exposure to ultraviolet light and water. 

Styrene—butadiene latexes generally are quite stable mechanically because of the presence of relatively large amounts of emulsifying and stabilizing agents, and therefore require addition of less stabilizer in compounding. The apphcations of SBR latex are classified in Table 21. This classification indicates the scope of the industry and illustrates the large number of diverse applications in which synthetic latices are employed. The latex types previously found most suitable for particular applications are also listed. 

Cure Characteristics. Methods of natural rubber production and raw material properties vary from factory to factory and area to area. Consequentiy, the cure characteristics of natural mbber can vary, even within a particular grade. Factors such as maturation, method and pH of coagulation, preservatives, dry mbber content and viscosity-stabilizing agents, eg, hydroxylamine-neutral sulfate, influence the cure characteristics of natural mbber. Therefore the consistency of cure for different grades of mbber is determined from compounds mixed to the ACSl formulation (27). The ACSl formulation is as follows natural mbber, 100 stearic acid, 0.5 zinc oxide, 6.0 sulfur, 3.5 and 2-mercaptobenzothiazole (MBT), 0.5. 

Sulfur polymer cement shows promise as an encapsulation and stabilization agent for use with low level radioactive and mixed wastes. Use of SPC allows accommodation of larger percentages of waste than PCC. As of this writing (1997), SPC-treated waste forms have met requirements of both the Nuclear Regulatory Commission (NRC) and the Environmental Protection Agency (EPA). 

Several stabilization agents are available, ie, protolytic enzymes, tannic acid, or various adsorbents such as polyvinylpyrroHdinone (PvPP) and nylon-6,6 or bentonite. The stabilizing agent is normally added during the transfer to the stabilizing tank and left for some hours to react. 

Hydrosulfite may be purchased as a proprietary formulation containing buffering and stabilizing agents, usually as a dry powder, but sometimes as a solution. The powder is pyrophoric and should be kept dry to avoid the possibiHty of fires. Alternatively, solutions of sodium hydrosulfite may be generated on-site by using a purchased solution of sodium borohydride and sodium hydroxide to reduce sulfur dioxide. 

Treatment of 2,6-dimethylaniline (121) with phosgene and triethylamine affords the corre-S]ionding isocyanate (122). Condensation of that reactive intermediate with N-isopropylpropyl-cne-1,3-diamine leads to formation of urea 123. This product, recainam (123), acts as membrane Stabilizing agent and thus exhibits both local anesthetic and antiarrhythmic activity [30]. 

Stsbilisierung, /. stabilization. Stsbilisienmgsmittel, n. stabilizing agent, stabilizer. 

Cromones are used to prevent asthma attacks. To be effective they have to betaken continuously. Their mechanism of action is poorly understood. Cromones (cromolyn sodium, nedocromil) act as mast cell-stabilizing agents,... 

Bergstralh DT, Ting JP (2006) Microtubule stabilizing agents their molecular signaling consequences and the potential for enhancement by drug combination. Cancer Treat Rev 32 166-179... 

The composite propints are not the only ones subject to degradation processes which affect shelf-life, although they are relative newcomers to propint history. In NC-based pro pints, NC decomposes slowly to release NOa which reacts catalytically to hasten the degradation in physical and ballistic properties. To slow the process, stabilizing agents such1 as diphenylamine or 2-... 

Rudolph, A.S., Crowe, J.H. Crowe, L.M. (1986). Effects of three stabilizing agents - proline, betaine and trehalose on membrane phospholipids. Archives of Biochemistry and Biophysics, 245, 134-43. 

Finally, Jessop and coworkers describe an organometalhc approach to prepare in situ rhodium nanoparticles [78]. The stabilizing agent is the surfactant tetrabutylammonium hydrogen sulfate. The hydrogenation of anisole, phenol, p-xylene and ethylbenzoate is performed under biphasic aqueous/supercritical ethane medium at 36 °C and 10 bar H2. The catalytic system is poorly characterized. The authors report the influence of the solubility of the substrates on the catalytic activity, p-xylene was selectively converted to czs-l,4-dimethylcyclohexane (53% versus 26% trans) and 100 TTO are obtained in 62 h for the complete hydrogenation of phenol, which is very soluble in water. 

When protective colloids are used as stabilizing agents, the following properties contributed by these stabilizing materials should be considered ... 

The practical aspects of stabilizing agents for suspensions are of great importance to the cosmetic and pharmaceutical industries. The following... 

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