New Yorker July 25, "Bloodsuckers" by John Colapinto (p. 72-81)
The FDA has approved only two living animals to be used as medical devices. The first was the maggot, approved in Jan. 2004, to consume infected tissue around wounds. The second, last summer, was the leech, which has been very useful in translant or re-attachment surgery and recovery, as it creates an "artificial circulation" until the new or reattached appendage can grow new veins. (p. 74)
Creepy, but cool at the same time.
There is a Philly connection. Roy T. Sawyer is the world's leading leech specialist.
In the early eighties, he formed a partnership with Andrei Budzynski, a professor of biochemistry at Temple University School of medicine, in Philadelphia. Budzynski isolated an enzyme from the giant leech's salivary glands which he and Sawyer called hementin.( p. 79)
Hementin can dissolve clots and may be useful for cardiovascular problems.