Silico

In particular, in silico methods are expected to speed up the drug discovery process, to provide a quicker and cheaper alternative to in vitro tests, and to reduce the number of compounds with unfavorable pharmacological properties at an early stage of drug development. Bad ADMET profiles are a reason for attrition of new drug candidates during the development process [9, 10]. The major reasons for attrition of new drugs are ... 

The reliability of the in silico models will be improved and their scope for predictions will be broader as soon as more reliable experimental data are available. However, there is the paradox of predictivity versus diversity. The greater the chemical diversity in a data set, the more difficult is the establishment of a predictive structure-activity relationship. Otherwise, a model developed based on compounds representing only a small subspace of the chemical space has no predictivity for compounds beyond its boundaries. 

The term virtual screening or in silico screening" is defined as the selection of compounds by evaluating their desirability in a computational model. The desirability comprises high potency, selectivity, appropriate pharmacokinetic properties, and favorable toxicology. 

R and M M Hann 2000. The In Silico World of Virtual Libraries. Drug Discovery Today 5 326-336. R and I D Kuntz 1990. Conformational Analysis of Flexible Ligands in Macromolecular eptor Sites. Journal of Computational Chemistry 13 730-748. 

Siheium-. siheon, silico-, silicide of. -amelsen-saiire, /. silicoformic acid (HSiOOH, existence unconfirmed). 

This solution is extracted several times with 5% acetic acid, until the silico-tungstate test (an identification test for alkaloids) yields a negative result, and the acetic solutions are washed with 10 ml ether. 

Sodium silicate and silico fluoride solutions as concrete surface hardeners 9/104... 

Both sodium silicate and silico fluoride solutions are applied to clean, dry, sound concrete floors as dilute aqueous solutions (10-15 per cent solids) in two to three applications, taking care to ensure that all material penetrates and is absorbed into the concrete surface. The silicate or silico fluoride reacts with the small amount of free lime in the cement to form glassy inert materials in the surface, and the successful application of both materials depends upon filling the micropores in the surface of good-quality concrete, leaving its surface appearance and non-skid characteristics virtually unchanged. 

The main difference between the two types are that the reaction products of the silico fluoride types are less soluble in water and are also harder, which may give better in-service performance but at a slightly higher material cost. However, with recent developments in floor-laying techniques, the concrete substrates for industrial floors are laid with much more dense low-porosity surfaces, so that neither silicate nor silico fluoride treatments are as effective as they used to be, when the concrete used had a slightly more open finish and hence was more receptive to these treatments. With modern concrete floors, it is imperative to wash any material not absorbed into the surface within a short period. Otherwise, unpleasant white alkaline deposits, which are difficult to remove, may occur. 

It is important to stress that neither sodium silicate nor silico fluoride will improve the performance of a poor, low-strength, dusty concrete floor and if the surface is too porous, there is no way that all the material applied can react with the relatively small quantity of free lime in the concrete surface. All that will happen is that the pores will be filled with non-reacted powder, producing a most unpleasant alkaline dust, which can be very irritating to the skin and eyes when the floor is put into service. 

Computational biology Computational molecular biology Biocomputing in silico biology... 

If structural information of the protein target is available, e.g., a crystal structure, in silico screening of huge virtual compound libraries can be conducted by the use of docking simulations. Based on identified primary hits, structural variations of the ligand can be evaluated by computational modeling of the ligand-protein complex. 

Common to all three aims is that silico-derived predictions can rationalize experimental efforts either by well-directed very specific molecular biological experiments like site directed mutations or e.g., by reducing the number of compounds to screen experimentally for drug design. 

Silico- and phosphorus borides crystallizing with ordered W5Si3-type structures, such as Ni4ftSi2B and Cr. 45P2B, are closely related structurally. ... 

Cationic low-coordinated n-bonded phosphorus compoimds add Lewis donors, such as amines or phosphines. In contrast to the trigonal bipyramide formed in donor-addition to the silico-nium cation, the phosphorus cations add donors in a perpendicular fashion, depending on the nature of the n-bonds toward phosphorus. According to quantum chemical calculations the various cations reveal different stabilities and hence a strong variation in donor addition abilities. 

Other materials, closely related to zeoHtes, with zeo-type structures are silico-aluminophosphates (SAPOs) and aluminophosphates (ALPOs) [6]. 

Moreover, there is a clear and obvious need for experimental work to be conducted in support of the development of accurate in silico methods. Bioinformaticians, like all other scientists physical or biological or social, need... 

Flower DR. Towards in silico prediction of immunogenic epitopes. Trends Immunol 2003 24 667-74. 

Defranoux NA, Stokes CL, Young DL, Kahn AJ. In silico modeling and simulation of bone biology a proposal. / Bone Miner Res 2005 20 1079-84. 

Figure 11.2 A decision tree, based on an associated inflnence diagram, can help organize and integrate information about risks and the way in which research work buys better information that allows choice of the options most likely to succeed. This example describes the relationship between in silico predictions and in vitro assay results for the same compound structures.

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