(August 2003) Antibiotics are compounds that act to kill or inhibit the growth of bacteria1. The etymology of the term can be broken down into two roots: the prefix “anti-” meaning “opposed to” or “preventing” and “biotic” coming from the Greek word for life. In nature, various microbes and fungi secrete these compounds to gain an advantage in their microenvironment and it is from these very organisms that antibiotics are commonly use isolated [1]. The Discovery of Antibiotics The stories of the discovery of antibiotics are dramatic and full of human interest, both on a global and personal scale. Two…

(August 2003) Prions and prion diseases have been widely discussed in the media in recent years. The interest in prions and prion diseases was stimulated by the outbreak of bovine spongiform encephalopathy (BSE or Mad Cow Disease) in Europe in the mid-nineteen-nineties. This is a relatively new area of study. What exactly has been discovered about prions and prion diseases? What Are Prions? Prions are proteins found on the plasma membrane (the membrane that surrounds a cell and defines its physical boundary). In mammals, prions are found in the highest concentration in cells of the central nervous system. In mammals…

(August, 2003) Flow cytometry is a technology that allows a single cell to be measured for a variety of characteristics, determined by looking at how they flow in liquid [1]. Instruments used for this can gather information about cells by measuring visible and fluorescent light emissions, allowing cell sorting based on physical, biochemical and antigenic traits. Flow Cytometers A flow cytometer, sometimes called a Fluorescence Activated Cell Sorter (FACS), has several key components [2] (see Figure 1): 1. A light or excitation source, typically a laser that emits light at a particular wavelength; 2. A liquid flow that moves the…