Glossary

Water which is free of most inorganic (not completely free, since Na is present in ample quantities) and most organic compounds.

A grade of purified water produced by the exchange of cations for hydrogen ions, and anions for hydroxyl ions.

Design Exposure Limit

Separation into constituent layers.

(ICH Q6A) Release of a drug (or drugs) at a time other than immediately following oral administration.

Modified release dosage forms showing a release of the active substance(s) which is delayed. Delayed release is achieved by a special formulation design and/or manufacturing method. Delayed release dosage forms include gastro-resistant preparations as defined in the general monographs on solid oral dosage forms.

Data that in the past existed on the computer as live data and was deleted by the computer system or by end-user activity. Deleted data remains on storage media in whole or in part until it is overwritten by ongoing usage or “wiped” with a software program specifically designed to remove deleted data. Even after data itself has been wiped, directory entries, pointers, or other metadata relating to the deleted data may remain on the computer.

A particular kind of mutation: loss of a piece of DNA from a chromosome. Deletion of a gene or part of a gene can lead to a disease or abnormality.

A description of a specific chromosome that uses defined mutations – specific deleted areas in the genome – as “biochemical signposts”, or markers for specific areas.

(ANSI) A character used to indicate the beginning or the end of a character string. Synonym: Separator.

Complete separation of the fetus from the woman by expulsion or extraction or any other means.

A localized area that is dissimilar to the surrounding areas with a defined boundary after electropolishing.

Severe impairment of mental functioning.

Sometimes used interchangeably with deionization, it refers to the removal of minerals and mineral salts using ion exchange. Water softening is a common form of demineralization.

Division of Ethics and Management Operations (CDRH)

Converting signals from a wave form [analog] to pulse form (digital).

Characteristics of subjects or study populations, which include such information as age, sex, family history of the disease or condition for which they are being treated, and other characteristics relevant to the study in which they are participating.

Drug Experience Network

Loss of native configuration of a macro-molecule (protein or nucleic acid) by physical or chemical means, usually accompanied by loss of biological activity. Denatured proteins often unfold their polypeptide chains and express changed properties of solubility. The separation of duplex nucleic acid molecules into single strands. Most commonly used by genetic engineers to describe the destruction of hydrogen bonds maintaining the double-stranded nature of all or part of a DNA molecule.

To induce structural alterations that disrupt the biological activity of a molecule. Often refers to breaking hydrogen bonds between base pairs in double-stranded nucleic acid molecules to produce single-stranded polynucleotides, or altering the secondary and tertiary structure of a protein, destroying its activity.

A protein having unfolded or disordered polypeptide chains, which render the molecule less soluble and usually nonfunctional. A protein can be refolded (renatured).

A polymer having a regular branched structure. If suitably functionalized (such as the benzyl alcohol-substituted) it may be used as a soluble support, in which case the desired, dendrimer-supported, material may be isolated by size-exclusion chromatography. Dendrimers may also be attached to a polymer and used as a solid support, with significantly increased loading over the initial resin.

One of the branching protoplasmic processes of the nerve cell.

High-speed centrifugation in which molecules “float” at a point where their density equals that in a gradient of cesium chloride or sucrose. The density gradient may either be formed before centrifugation by mixing two solutions of different density (as in sucrose density gradients) or it can be formed by the process of centrifugation itself (as in CsCl and Cs2SO4 density gradients).

The mass of fluid per unit volume. For a compressible fluid flow, the density can vary from place to place.