ABSTRACT
A study of the decomposition of alpha-hydroxydialkylnitrosamines in aqueous 9% acetonitrile, with an ionic strength of 1 M (NaClO(4)), at 25 degrees C is reported. Plots of the logarithm of the buffer-independent rate constant, k(o), against pH are concave up and indicate a three-term rate law for the solvent reaction, including acid (k(H+)-, base (k(OH))-, and pH-independent (k(HOH)) terms. Secondary alpha-deuterium isotope effects for compound 1a, (N-nitrosomethylamino)phenylmethanol, are as follows: k(alpha)(H)/k(alpha)(D) = 1.12 +/- 0.03 and 1.19 +/- 0.02 for k(H+) and k(OH), respectively. General acid (k(HA)) and general base (k(A-) catalysis by more acidic carboxylic acid buffers is also observed. Structure reactivity and other parameters obtained in this study, and their changes with substrate and catalyst structure, permit the assignment of mechanisms for the k(H+) k(OH), k(HA), and k(A-) processes.
Subject(s)
Nitrosamines/chemistry , Nitroso Compounds/chemistry , Buffers , Catalysis , Hydrogen/chemistry , Hydrogen-Ion Concentration , Hydroxyl Radical , Kinetics , Magnetic Resonance Spectroscopy , Solubility , Solutions , SolventsABSTRACT
The efficiency of newly synthesized oxime derivatives of quinuclidinium were tested in vitro on soman inhibited acetylcholinesterase (AChE) of human erythrocytes and in vivo using soman poisoned mice. For this purpose, the inhibitory power of oximes (IC50), acute toxicity (LD50) as well as reactivating and protective capacities with respect to soman-inhibited AChE were determined for each of the oximes. All oximes tested were ineffective in vitro but protected mice very efficiently (BM-1 protects against 4LD50 of soman). The results indicate that the in vivo effectiveness of quinuclidinium oximes against soman poisoning may not be related to reactivation or protection of AChE but rather to some other mechanism of the cholinergic system.
Subject(s)
Antidotes/therapeutic use , Oximes/therapeutic use , Quinuclidines/therapeutic use , Soman/antagonists & inhibitors , Soman/poisoning , Acetylcholinesterase/blood , Animals , Cholinesterase Reactivators/blood , Cholinesterase Reactivators/therapeutic use , Erythrocytes/drug effects , Erythrocytes/enzymology , Humans , Lethal Dose 50 , Male , Mice , Mice, Inbred BALB CABSTRACT
PIP: The authors survey the migration history of the territories that make up modern Yugoslavia. The discussion includes migration patterns into and out of Yugoslavia and their socioeconomic and political determinants. The authors analyze reasons for migration to specific countries and conclude with a discussion of current Yugoslav migration policy. (SUMMARY IN ENG)^ieng
Subject(s)
Emigration and Immigration , Politics , Public Policy , Socioeconomic Factors , Demography , Developed Countries , Economics , Europe , Population , Population Dynamics , YugoslaviaABSTRACT
"The present migration situation is analysed in regard to the labour market, the legal status of migrants, return flows and reintegration, and the position of second generation migrants.... In the second part of the paper the author attempts to discern the future of migration in Europe on the basis of existing demographic trends in Europe and the world, present trends [in] the labour market, and current technological changes. In this context he offers an outline for the Yugoslav migration perspective." (SUMMARY IN ENG)
