microbes(305 KB) by
Randall C. Willis
Methods such as the enzyme-linked immunosorbent assay rely on the specific
interaction of antibodies directed against microbial surface antigens.
Such assays can identify microbial isolates, but their effectiveness
is often compromised because many microbes have found ways of altering
their surface antigenicity. New methods have been developed that identify
microbes by a relatively unchanging factor: their genetic material.
For example, Canadian researchers recently developed an assay to distinguish
between two Candida species in blood samples. This is especially
important because C. albicans and C. dubliniensis require
entirely different patient treatment regimens.
therapy: Hope in a cautionary tale(141 KB)
by Mark S. Lesney
In the early 1990s, gene therapy changed from science fantasy to viable
technique with the work of cancer researcher W. French Anderson. Since
then, it has proved a cautionary tale of the rocky and frustrating
road toward success. Gene therapy, especially when combined with traditional
chemotherapy, has shown itself capable of causing lethal tumors to
vanish. But there have been nightmare chapters as well. In clinical
trials, gene therapy has killed one youth and caused cancer in a three-year-old
boy. Although directed targeting does not eliminate insertional mutagenesis
or oncogenesis, it has the potential to limit the number of statistical
chances for such a problem to occur.