Organic selectivity

Kenakin, T. P., Ambrose, J. R., and Irving, P. E. (1991). The relative efficiency of beta-adrenoceptor coupling to myocardial inotropy and diastolic relaxation Organ-selective treatment of diastolic dysfunction. J. Pharmacol. Exp. Ther. 257 1189—1197. 

Kenakin, T. P. (1985). Drug and organ selectivity Similarities and differences. In Advances in drug research, Vol. 15, edited by B. Test, pp. 71-109. Academic Press, New York. 

Various wastes available as carbon substrates for SCP productions are listed in column A. Match each waste with a suitable organism (perhaps more than one) from column B. For each organism select the most appropriate production system from column C. 

Formal Organization selects/pairs mentees and mentor Mentor selects mentee with help from HR Mentee selects mentor (with help from HR) from a panel of well-trained mentors... 

In the presence of air, the roots, coleoptile, mesocotyl, endosperm, scutellum, and anther wall of maize synthesise a tissue-specific spectrum of polypeptides. The scutellum and endosperm of the immature kernel synthesise many or all of the ANPs constitutively, along with many other proteins under aerobic conditions. Under anaerobic conditions all of the above organs selectively synthesise only the ANPs. Moreover, except for a few characteristic qualitative and quantitative differences, the patterns of anaerobic protein synthesis in these diverse organs are remarkably similar (Okimoto et al., 1980). On the other hand, maize leaves, which have emerged from the coleoptile, do not incorporate labelled amino acids under anaerobic conditions and do not survive even a brief exposure to anaerobiosis (Okimoto et al., 1980). 

We have developed a quantitative structure-activity model for the variations in potency among the nitrosamines and, more recently, a related model for the variation in target organ for a smaller set of nitrosamines. We are currently developing a model for interspecies variation in susceptibility toward carcinogenic nitrosamines. The model for organ selectivity requires terms for the parent nitrosamine as well as for the hypothesized metabolites while the model for potency variations contains terms only for the unmetabolized parent compound. 

The degradation of 6-methylpyridine-3-carboxylate by an organism selected by enrichment with 6-methylpyridine-3-carboxylate takes place by selective hydroxylation at C-2,... 

Certain esters have often been employed in attempts to confer organ selectivity to molecules possessing carboxyl functions. Thus, for example, treatment of piperidinecarboxylic acid 76 with N-hydroxysuccinimide and DCC affords the ester 77. In a convergent synthesis, the anion from diphenylacetonitrile (78) is alkylated with dibromoethane to afford the bromide 79. Alkylation of the piperidine derivative 77 with that halide 79 gives the anti-diarrheal agent difenoximide (80). The same sequence starting with the phenoxyethyl ester 81 gives fetoxylate (82). 

Quinazolines containing an electron-rich carbocyclic ring have been associated with smooth muscle relaxant activity. The mechanism of action (phosphodiesterase inhibition, a- adrenergic blockade) and organ selectivity (bronchi, vascular smooth muscle) vary greatly with substitution on the heterocyclic ring. 

In the case of cortical cluster organization, selective elimination of collaterals, and not cell death, is the essential molding parameter. 

St. John T, Coleman D, Reid C (1983) Growth and spatial distribution of nutrient-absorbing organs selective exploitation of soil heterogeneity. Plant Soil 71 487-493. doi http //dx.doi. 

Trust in risk information about food-related hazards is an important determinant of public reactions to risk information. One of the central questions addressed by the risk communication literature is why some individuals and organizations are trusted as sources of risk information whereas others are not. Industry and government often lack public trust, whereas other sources are highly trusted (such as consumer organizations, selected media, and physicians). Their analyses indicate that knowledge in itself does not make one a trusted source, but that trusted sources are characterized by multiple positive attributes. 

De Benedetti, P.G., Heible, J.P. and Giardina, D. (1996) al-Adrenoceptors subtype- and organ-selectivity of different agents, in Perspectives in... 

F4. Fidler, I. J., and Nicolson, G. L., Organ selectivity for survival and growth of B16 melanoma variant tumor lines. J. Natl. Cancer Inst. (U.S.) 57, 1199-1201 (1976). 

The pharmacokinetic implications of these findings are not straightforward. One important factor that must also be considered is hepatic extraction, which is higher for lovastatin than for its hydroxy acid metabolite [188], Some lactones are useful prodrugs of HMG-CoA reductase inhibitors due to this organ selectivity coupled with the efficiency of enzymatic hydrolysis. However, other factors may also influence the therapeutic response, in particular the extent and rate of metabolic reactions that compete with or follow hydrolysis, e.g., cytochrome P450 catalyzed oxidations, /3-oxidation, and tau-... 

Substances acting antagonistically at the M-cholinoceptor are designated parasympatholytics (prototype the alkaloid atropine actions shown in red in the panels). Therapeutic use of these agents is complicated by their low organ selectivity. Possibilities for a targeted action include ... 

Special precautions Store behind lead shielding. Follow institutional regulations regarding type and location of dosimeter. Avoid working immediately above open containers. Because no organ selectively concentrates sodium metabohtes, the entire body is considered to be... 

Special precautions Avoid sulfurous vapors by working in a chemical fume hood. Because no organ selectively concentrates sulfur metabolites, the entire body is the critical organ in terms of dose. The effective biological half-life in humans is around 90 days. The maximum range in air is 0.24 meters. 

The pharmacological agents useful in this disorder may be grouped under five broad categories of treatment (Table 64.2). Such a classification system takes into account the mode of drug action, the route of administration, and the means by which target organ selectivity is achieved. 

Selectivity of action is based on several factors. Some drugs stimulate either muscarinic receptors or nicotinic receptors selectively. Some agents stimulate nicotinic receptors at neuromuscular junctions preferentially and have less effect on nicotinic receptors in ganglia. Organ selectivity can also be achieved by using appropriate routes of administration ("pharmacokinetic selectivity"). For example, muscarinic stimulants can be administered topically to the surface of the eye to modify ocular function while minimizing systemic effects. 

From the beginning of the development of nuclear power, nuclear scientists had agonized about what safety measures were needed in power plants and what health impacts radioactivity releases might cause. They published their analyses and arguments for all to see, and it took little effort for the antinuclear activists to collect, organize selectively, and distort this information into ammunition for their battle. People experienced in debate and political fights are well prepared to do that... 

Microbes acquire iron by utilizing very specific, low molecular weight iron chelators called siderophores. The resistance of bacteria to previously effective antibiotics can be circumvented in part by covalent coupling of antibiotics to siderophores. Some synthetic siderophores have been found to possess significant antibacterial activity themselves. They have also been found to have considerable potential as nontoxic, organ selective MRI contrast agents (27). 

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