Irrational approach

The basic steps of the irrational or random scanning approach are shown in Fig. 3.1. 

This approach to drug discovery commences with the collection of natural materials from their habitats. Such collections typically gather 1-5 kg of materials, which may consist of leaves, shoots, bark, and roots of plants. Marine life forms are collected as well. The locations are recorded, to facilitate further collection of materials should that be required. 

An important aspect of natural product collection is to provide biodiversity, that is, products with different and diverse chemical compositions so that many potential variations of chemical compositions and structures can be extracted for testing. 

Collection of natural products, or bioprospecting, used to be relatively straightforward, with little formality or encumbrances. Now, however, there are new rules (Exhibit 3.2) to protect the natural habitats. 

Until recently, obtaining samples of plants, microorganisms, animals, and marine life forms was straightforward. Normally, a researcher would arrive at the collection site with permission from the local authority and collect samples without much restriction. 

There are two main approaches to discovering small molecule drugs the irrational approach, or the more recent structured rational approach. Antisense and chiral drugs are two other drug discovery methodologies. 

Chapter 3 Drug Discovery Small Molecule Drugs 

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Xo is Irrational Using the same argument as given above, orbits for irrational Xq must be nonperiodic, with the attractor in this case being the entire interval. Because any finite sequence of digits appears infinitely many times within the binary decimal representation of almost all irrational numbers in [0,1] (all except for a set of measure zero), the orbit of almost all irrationals approaches any x G [0,1] to within a distance e << 1 an infinite number of times i.e., the Bernoulli shift is ergodic. 

Irrational Approach This approach is the historical method of discovering and developing drugs. It involves empirical observations of the pharmacological effects from the screening of many chemical compounds, mainly those from natural products. The active component that gives rise to the observed effects is isolated. The chemical formula is determined, and modifications are made to improve its properties. This approach has yielded many drugs available today. 

Describe the irrational approach to drug discovery and provide examples of drugs discovered using this approach. 

The discovery of pharmaceuticals commences with the scanning of hundreds of compounds, whether with actual materials (irrational approach) or virtual simulations (rational approach). To discover biopharmaceuticals, we have to examine the compounds within us, for example, hormones or other biological response modihers, and determine how they affect the biological processes. In some cases, we study pathogens such as the influenza virus or bacteria to derive the vaccines. In other cases, we copy these biological response modifiers and use them as replacement therapy. 

For TM to be accepted into mainstream medical treatment, a likely scenario is the application of scientific methodologies and controls for TM development, evaluation, and production. Many of the tools for high throughput screening (HTS) and assay systems can be used to test the efficacy of TM, similar to the irrational approach of screening natural products. Pharmacology studies have to be conducted in accordance with Good Laboratory Practice (GLP). 

The fear has been expressed that with the increased interest in alternative medicine, we [shall] see a reversion to irrational approaches to medical practice (28). The only way to minimize incompetence is proper education and training, combined with responsible regulatory control. While training and control are self-evident features of mainstream medicine they are often not fully incorporated in complementary medicine. Thus the issue of indirect health risk is particularly pertinent to complementary medicine. Whenever complementary practitioners take full responsibility for a patient, this should be matched with full medical competence if on the other hand, competence is not demonstrably complete, the practitioner in question should not assume full responsibility (29). 

Screening combinatorial libraries should not imply a random or irrational approach to drug discovery. Far from obviating the use of computers, the increased complexity of combinatorial drug discovery makes their use ever more essential. Although the number of compounds that could be made is enormous, a well-planned experimental design selects a reasonable number of compounds that sample the range of accessible properties. 

Unless you are prepared to adopt a highly irrational approach to sound design, you should always give preference to basing your new instruments on well-documented acoustic theories see Howard and Angus (1996) for a good introduction to acoustics. Acoustic musical instruments are a reliable point of departure because the human ear is familiar with them. However, be wary here, because the expression point of departure does not necessarily mean that you should always attempt to imitate these instruments. Bear in mind that software sound synthesis gives you the power to create new instruments and sonorities. 

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