Membrane effect

Rysee, H. J. P. a membrane effect of basic polymers dependent on molecular size. Nature 1967. 215, 934—936. 

The mechanisms of the allergy-like reactions to RCM are still a matter of speculation (table 2). Anaphylaxis to RCM has been discussed to be due to a direct membrane effect possibly related to the osmolality of the RCM solution or the chemical structure of the RCM molecule (pseudo-allergy) [2], an activation of the complement system [27], a direct bradykinin formation [28], or an IgE-mediated mechanism [3]. 

TSUCHIYA H (2001) Stereospecificity in membrane effects of catechins. Chem Biol Interact. 134 41-54. 

The second part, on biological applications of interfacial phenomena, has ten chapters that deal successively with protein encapsulation, membranes, effects of phospholi-... 

Patients with acute hyperkalemia usually require other therapies to manage hyperkalemia until dialysis can be initiated. Patients who present with cardiac abnormalities caused by hyperkalemia should receive calcium gluconate or chloride (1 g intravenously) to reverse the cardiac effects. Temporary measures can be employed to shift extracellular potassium into the intracellular compartment to stabilize cellular membrane effects of excessive serum potassium levels. Such measures include the use of regular insulin (5 to 10 units intravenously) and dextrose (5% to 50% intravenously), or nebulized albuterol (10 to 20 mg). Sodium bicarbonate should not be used to shift extracellular potassium intracellularly in patients with CKD unless severe metabolic acidosis (pH less than 7.2) is present. These measures will decrease serum potassium levels within 30 to 60 minutes after treatment, but potassium must still be removed from the body. Shifting potassium to the intracellular compartment, however, decreases potassium removal by dialysis. Often, multiple dialysis sessions are required to remove potassium that is redistributed from the intracellular space back into the serum. 

Cevc, G. Watts, A. Marsh, D., Titration of the phase transition of phosphatidylserine bilayer membranes. Effects of pH, surface electrostatics, ion binding, and head group hydration. Biochemistry 20, 4955 -965 (1981). 

Gutknecht, J. Tosteson, D. C., Diffusion of weak acids across lipid membranes Effects of chemical reactions in the unstirred layers, Science 182, 1258-1261 (1973). 

Gutknecht, J. Bisson, M. A. Tosteson, F. C., Diffusion of carbon dioxide through lipid bilayer membranes. Effects of carbonic anhydrase, bicarbonate, and unstirred layers, J. Gen. Physiol. 69, 779-794 (1977). 

The nion term is simply an expression for the osmotic pressure generated across a semipermeable membrane effectively, the gel serves as a membrane which restricts the polyelectrolytes to one phase, while small ions can readily redistribute between phases. Assuming that the ions form an ideal solution, the expression for nion becomes simply... 

Subczynski, W.K., E. Markowska, and J. Sielewiesiuk. 1993. Spin-label studies on phosphatidylcholine-polar carotenoid membranes Effects of alkyl-chain length and unsaturation. Biochim. Biophys. Acta 1150 173-181. 

So far, SAR studies for P-gp have been performed on the basis of classical QSAR principles which were designed for transporters or receptors, which naturally bind one specific substrate from an aqueous environment. The assumptions made are that (i) the modeled conformation is the bioactive one (ii) the binding site and/or mode is the same for all modeled compounds (iii) interactions between the drug and the binding site are mainly due to enthalpic processes (e.g., van der Waals interactions) and (iv) solvent or membrane effects are negligible (cf. Ref. [35]). 

Gudheti, M. V., Mlodzianoski, ML, and Ffess, S. T. (2007) Imaging and shape analysis of giant unilamellar vesicles (GUVs) as model plasma membranes Effect of fnms-DOPC (dielaidoyl phosphatidylcholine) on membrane properties. Biophys. J. 10.1529/biophysj.106.103374. 

Progesterone produces direct membrane effects [16]. These include actions that promote maturation of spermatozoa as well as oocytes and facilitation of the release of neurotransmitters such as dopamine and LH-releasing hormone (LHRH) (Fig. 52-7). Membrane actions of progesterone also activate oxytocin receptors in the hypothalamus in a way that enables oxytocin to turn on sexual behavior in the estrogen-primed female rat [3],... 

Investigations of the cellular effects of radiofrequency radiation provide evidence of damage to various types of avian and mammalian cells. These effects involve radiofrequency interactions with cell membranes, especially the plasma membrane. Effects include alterations in membrane cation transport, Na+/K+-ATPase activity, protein kinase activity, neutrophil precursor membrane receptors, firing rates and resting potentials of neurons, brain cell metabolism, DNA and RNA synthesis in glioma cells, and mitogenic effects on human lymphocytes (Cleary 1990). 

Lund AE, Narahashi T (1983) Kinetics of sodium channel modification as the basis for the variation in the nerve membrane effects of pyrethroids and DDT analogs. Pestic Biochem Physiol 20 203-216... 

Bienvenue, E., Boudou, A., Desmazes, J. P., Gavach, C., Georgescauld, D., Sandeaux, J., Sandeaux, R. and Seta, P. (1984). Transport of mercury compounds across bimolecular lipid membranes effect of lipid composition, pH and chloride concentration, Chem.-Biol. Interact., 48, 91-101. 

Gad, S.C., Reilly, C., Siino, K.M. and Gavigan, F.A. (1985). Thirteen cationic ionophores Neurobehavioral and membrane effects. Drug Chemical Toxicol. 8 (6)451-468. 

Table 11.1 High-temperature membranes effect of temperature on recovery and rejection. 

Hellenbrecht and co-workers (18) have now produced conclusive evidence showing that the magnitude of these membrane effects correlate directly with lipophilicity. 

Rytdmaa, M., and Kinnunen, P.K.J., 1995, ReversibUity of the binding of cytochrome c to Uposomes. Implications for lipid-protein interactions./. B/oZ. Chem., 270 3197-3202 Salamon, Z., and ToUin, G., 1996, Surface plasmon resonance studies of complex formation between cytochrome c and bovine cytochrome c oxidase incorporated into a supported planar Upid bUayer. II. Binding of cytochrome c to oxidase-containing cardiohpin /phosphatidylcholine membranes. Biophys. J., 71 858-867 Salamon, Z., and ToUin, G., 1997, Interaction ofhorse heart cytochrome c with Upid bilayer membranes effects on redox potentials. J. Bioenerg. Biomembr. 29 211-221 Scarlett, J.L., and Murphy, M.P., 1997, Release of apoptogenic proteins from the... 

Rashba-Step, J., Tatoyan, A., Duncan, R,. Ann, D., Pushpa-Rehka, T.R., and Sevanian, A, 1997, PhosphoUpid peroxidation induces cytosolic phospholipase A2 activity membrane effects versus enzyme phosphorylation, Arcii. Biochem. Biophys. 343 44-54. 

Veiga, M.P., Arrondon, J.L. Goni, P.M. and Alonso, A., 1999, Ceramides in phospholipid membranes effects on bilayer stability and transition to nonlamellar phases. Biophys. 7. 76 342-350... 

Kolosov, E. N., N. I. Starkovskii, S. G. Gul yanova and V. M. Gryaznov. 1988. Oxygen permeability of thin silver membranes Effect of the adsorption of benzene on the oxygen transfer process. Russian J. Phys. Chem. 62(5) 661-663. 

Papahadjopoulos D, Nir S, Oki S. Permeability properties of phospholipid membranes effect of cholesterol and temperature. Biochim Biophys Acta 1972 ... 

Telang S, Tony C, Williams GM. 1982. Epigenetic membrane effects of a possible tumor promoting type on cultured liver cells by the non-genotoxic organochlorine pesticides chlordane and heptachlor. Carcinogenesis 3 1175-1178. 

For the purposes of the present discussion the term curariform neuromuscular block will be taken to refer to a post-neural membrane effect, resulting in paralysis of striated muscle, having the following characteristics ... 

Mechanism of action Na"", K -ATPase inhibition Na /H " exchange mechanism inhibition (proximal tubule) Aldosterone antagonism Membrane effect... 

Ketamine and also tiletamine are structurally and pharmacologically related to phencyclidine. Its mechanism of action is not well understood. It has been suggested that it blocks the membrane effects of the excitatory neurotransmitter glutamic acid. Ketamine produces dissociative anesthesia, which means that the patient seems to be awake but there are no responses to sensory stimuli. Ketamine, which can be administered IV or IM, has strong analgesic activity. It is especially indicated for interventions of short duration without any need for skeletal... 

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