Exhibit 25.1



                              POWER OF ATTORNEY


      KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Joseph Peterson, M.D. and Ronald W.
Rudolph and each of them, as his or her true and lawful attorneys-in-fact and
agents, with full power of substitution and re-substitution, for him or her and
in his or her name, place and stead, in any and all capacities, to sign any and
all amendments (including post-effective amendments) to this Report on Form
10-K, and to file the same, with all exhibits thereto, and other documents in
connection therewith, with the Securities and Exchange Commission, granting unto
said attorneys-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite and necessary to be done
in connection therewith, as fully to all intents and purposes as he might or
could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents, or any of them, or their or his substitute or
substitutes, may lawfully do or cause to be done by virtue hereof.

      Pursuant to the requirements of the Securities and Exchange Act of 1934,
this report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the dates indicated:




         Signature                              Title                       Date
         ---------                              -----                       ----


                                                                 
/s/ Joseph Peterson, M.D.            Chief Executive Officer,          March 29, 2002
- ---------------------------
Joseph Peterson, M.D.                President and Director
                                     (Principal Executive Officer)

/s/ Ronald W. Rudolph                Executive Vice President,         March 29, 2002
- ---------------------------
Ronald W. Rudolph                    Finance
                                     and Chief Financial Officer
                                     (Principal Financial and
                                     Accounting Officer)

/s/ Karen Brenner                    Director                          March 29, 2002
- ---------------------------
Karen Brenner


/s/ William E. Brock                 Director                          March 29, 2002
- ---------------------------
William E. Brock


/s/ Elliot Ettenberg                 Director                          March 29, 2002
- ---------------------------
Elliot Ettenberg


/s/ Jonathan S. Holman               Director                          March 29, 2002
- ---------------------------
Jonathan S. Holman


/s/ Jeremy M. Jones                  Director                          March 29, 2002
- ---------------------------
Jeremy M. Jones