Category Archives: Nature as source of drugs

In 1990, the two major funding

In 1990, the two major funding agencies, DOE and NIH, developed a memorandum of understanding in order to coordinate plans and set the clock for the initiation of the Project to 1990. At that time, David Galas was Director of the renamed «Office of Biological and Environmental Research» in the U.S. Department of Energy’s Office of Science and James Watson headed the NIH Genome Program. In 1993, Aristides Patrinos succeeded Galas and Francis Collins succeeded James Watson, assuming the role of overall Project Head as Director of the U.S. National Institutes of Health (NIH) National Human Genome Research Institute. A working draft of the genome was announced in 2000 and a complete one in 2003, with more detailed analysis still being published.

Researchers published the

Researchers published the first sequence-based map of large-scale structural variation across the human genome in the journal Nature in May 2008. Large-scale structural variations are differences in the genome among people that range from a few thousand to a few million DNA bases; some are gains or losses of stretches of genome sequence and others appear as re-arrangements of stretches of sequence. These variations include differences in the number of copies individuals have of a particular gene, deletions, translocations and inversions.

Absolute bioavailability compares the bioavailability

Absolute bioavailability compares the bioavailability of the active drug in systemic circulation following non-intravenous administration (i.e., after oral, rectal, transdermal, subcutaneous, or sublingual administration), with the bioavailability of the same drug following intravenous administration. It is the fraction of the drug absorbed through non-intravenous administration compared with the corresponding intravenous administration of the same drug. The comparison must be dose normalized (e.g., account for different doses or varying weights of the subjects); consequently, the amount absorbed is corrected by dividing the corresponding dose administered.

In response to specific cases in which unfavorable

In response to specific cases in which unfavorable data from pharmaceutical company-sponsored research was not published, the Pharmaceutical Research and Manufacturers of America have published new guidelines urging companies to report all findings and limit the financial involvement in drug companies of researchers. US congress signed into law a bill which requires phase II and phase III clinical trials to be registered by the sponsor on the clinical trials website run by the NIH.

Protein-coding sequences represent

Protein-coding sequences represent the most widely studied and best understood component of the human genome. These sequences ultimately lead to the production of all human proteins, although several biological processes (e.g. DNA rearrangements and alternative pre-mRNA splicing) can lead to the production of many more unique proteins than the number of protein-coding genes.

Humans have undergone

Humans have undergone an extraordinary loss of olfactory receptor genes during our recent evolution, which explains our relatively crude sense of smell compared to most other mammals. Evolutionary evidence suggests that the emergence of color vision in humans and several other primate species has diminished the need for the sense of smell.

Many aspects of drug development are

Many aspects of drug development are focused on satisfying the regulatory requirements of drug licensing authorities. These generally constitute a number of tests designed to determine the major toxicities of a novel compound prior to first use in man. It is a legal requirement that an assessment of major organ toxicity be performed (effects on the heart and lungs, brain, kidney, liver and digestive system), as well as effects on other parts of the body that might be affected by the drug (e.g. the skin if the new drug is to be delivered through the skin). While, increasingly, these tests can be made using in vitro methods (e.g. with isolated cells), many tests can only be made by using experimental animals, since it is only in an intact organism that the complex interplay of metabolism and drug exposure on toxicity can be examined.

Alternatively, many American

Alternatively, many American pharmaceutical companies have moved some clinical trials overseas. Benefits of conducting trials abroad include lower costs (in some countries) and the ability to run larger trials in shorter timeframes. Critics have argued that clinical trials performed outside the U.S. allow companies to avoid many of the FDA’s regulations, since the FDA audits these trials less frequently than U.S. studies. For drug applications approved by the FDA in 2008, 0.7 percent of foreign clinical study sites were audited by the FDA compared to 1.9 percent domestically. Other criticisms of foreign clinical studies, especially in developing countries, relate to the rights and welfare of study participants, integrity of study data, and relevance of data to the U.S. population.

Natural products sometimes have

Natural products sometimes have pharmacological or biological activity that can be of therapeutic benefit in treating diseases. As such, natural products are the active components of many traditional medicines. Furthermore synthetic analogs of natural products with improved potency and safety can be prepared and therefore natural products are often used as starting points for drug discovery. In fact, natural products are the inspiration for approximately one half of U.S. Food and Drug Administration-approved drugs.

In addition to the ncRNA

In addition to the ncRNA molecules that are encoded by discrete genes, the initial transcripts of protein coding genes usually contain extensive noncoding sequences, in the form of introns, 5’-untranslated regions (5’-UTR), and 3’-untranslated regions (3’-UTR). Within most protein-coding genes of the human genome, the length of intron sequences is 10- to 100-times the length of exon sequences (Table 2).