Biological Actions

Corrosion associated with the action of micro-organisms present in the corrosion system. The biological action of organisms which is responsible for the enliancement of corrosion can be, for instance, to produce aggressive metabolites to render the environment corrosive, or they may be able to participate directly in the electrochemical reactions. In many cases microbial corrosion is closely associated with biofouling, which is caused by the activity of organisms that produce deposits on the metal surface. 

The following chemical databases are available for searching in MACCS-II. ChemicalDirectoy Database contains a combined catalogue of 66 commercial suppHers of more than 77,000 organic chemicals. AL4.CCS-II Drug Data eport based on the Prous Dmg Data Report, includes 39,000 compounds with information on therapeutic indication, biological action, phase of development, related patents, and Hterature references. MUSE Database the tutorial database for MACCS-II, contains over 100 compounds. 

The information contained in the chemical stmcture of a given ligand is without value unless decoded and executed by the appropriate receptor. The pharmacologic analysis of dmg—receptor interactions is based on the understanding of how the dmg is recognized by the receptor, how the dmg—receptor complex forms, and how the dmg—receptor complex initiates its biological action (12). 

The PGs, PGI2 and TXA2 collectively exhibit a wide variety of biochemical and pharmacological activities and are iavolved ia both physiological and pathophysiological processes. However, the iadividual compounds show different overall activity profiles sometimes ia opposiag directions. Excellent reviews are available (59—64). A survey of some of the more important biological actions of the prostanoids foUow. 

Biochemical Oxygen Demand. The biochemical oxygen demand (BOD) test is an empirical determination of the oxygen requirement of a sample. It is most often appHed to wastewaters, industrial effluents, and poHuted waters. The decrease in the dissolved oxygen concentration resulting primarily from biological action is measured after storage for 5 d at 20°C. 

Technology Description Hydrolysis is the process of breaking a bond in a molecule (which is ordinarily not water-soluble) so that it will go into ionic solution with water. Hydrolysis can be achieved by the addition of chemicals (e.g., acid hydrolysis), by irradiation (e.g., photolysis) or by biological action (e.g., enzymatic bond cleavage). The cloven molecule can then be further treated by other means to reduce toxicity. 

Aerobic Treatment. The activated sludge process depends on aerobic biological action. In this case the microorganisms, in searching for food, break down the complex organic substances into simple stable substances. This process results in the removal of soluble and suspended organic matter from wastewater. 

The simplification of the local anesthetic phaimacophore of cocaine to an aryl substituted ester of ethanolamine has been described previously. Atropine (S2) is a structurally closely related natural product whose main biologic action depends on inhibition of the parasympathetic nervous system. Among its many other actions, the compound exerts useful spasmolytic effects. 

Acylation of a sulfonamide on the amide nitrogen serves to remove the sometimes objectionable taste of these drugs. Reac-I ion of intermediate, 154, with acetic anhydride followed by reduction of the nitro group affords acetyl methoxyprazine (156). The last, which has much the same biologic action as Mie parent compound, is used for oral administration in syrups. 

Taxol s journey to the clinic was slow and arduous. Initial difficulties with aqueous solubility and lack of knowledge regarding its mechanism, of action delayed its development until 1979 when, in another seminal paper in the field, S.B.Horwitz and her collaborators disclosed their findings on the interaction of taxol with microtubules.4 Taxol s unique biological action, which includes promotion of microtubule formation and microtubule stabilization, stimulated a renewed interest in taxol as a potential drug candidate. The problem of procuring adequate supplies of taxol became even... 

Several mechanisms serve to terminate the biological actions of noradrenaline and adrenaline. From the... 

The biological actions of adrenaline and noradrenaline are mediated via nine different G-protein-coupled receptors, which are located in the plasma membrane of neuronal and nonneuronal target cells. These recqrtors are divided into two different groups, a-adrenergic receptors and P-adrenergic recqrtors (see P-adrenergic system). 

Antidiabetic Drugs other than Insulin. Table 2 Tissue expression, ligands, genes activated, and biological actions of the peroxisome proliterator-activated receptor-y (PPARy)... 

Biological actions Adipocyte differentiation fatty acid uptake lipogenesis glucose uptake other effects on nutrient metabolism which lower hepatic glucose production... 

The incretin effect is reduced in type 2 diabetes, and this is attributed, at least in part, to reduced secretion of GLP-1. The biological actions of GLP-1 remain essentially intact in type 2 diabetes, but administration of extra GLP-1 is not a practical therapeutic option because the peptide is degraded rapidly if A < 2 min) by the enzyme dipeptidyl peptidase IV (DPP-4). DPP-4 cleaves the N-terminal dipeptide from many of the peptides that have either an alanine or a proline residue penultimate to the N-terminus (Fig. 6). 

The atrial natriuretic peptide (ANP) belongs to a family of hormones that have structural similarity and some biological actions in common, such as natriuresis and haemoconcentration. It is synthesized and secreted by the cardiac atrium in response to increased atrial pressure. ANP is believed to act physiologically in an opposing manner to AVP... 

Way KJ, Chou E, King GL (2000) Identification of PKC-isoform-specific biological actions using pharmacological approaches. Trends Pharmacol Sci 21 181-187... 

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