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Exhibit 3.3

                          CERTIFICATE OF INCORPORATION

                                       OF

                           BRITWILL HEALTHCARE COMPANY

                                    * * * * *

                  1. The name of the corporation is

                           BRITWILL HEALTHCARE COMPANY

                  2. The address of its registered office in the State of
Delaware is Corporation Trust Center, 1209 Orange Street, in the City of
Wilmington, County of New Castle. The name of its registered agent at such
address is The Corporation Trust Company.

                  3. The nature of the business or purposes to be conducted or
promoted is to engage in any lawful act or activity for which corporations may
be organized under the General Corporation Law of Delaware.

                  4. The total number of shares of stock which the corporation
shall have authority to issue is one million (1,000,000) and the par value of
each of such shares is One Dollar ($1.00) amounting in the aggregate to One
Million Dollars ($1,000,000).

                  The holders of common stock shall, upon the issuance or sale
of shares of stock of any class (whether now or hereafter authorized) or any
securities convertible into such stock, have the right, during such period of
time and on such conditions as the board of directors shall prescribe, to
subscribe to and purchase such shares or securities in proportion to their
respective holdings of common stock, at such price or prices as the board of
directors may from time to time fix as may be permitted by law.

                  5A. The name and mailing address of each incorporator is as
follows:

                      NAME                                  MAILING ADDRESS
                      ----                                  ---------------

                  L. B. Rush                          811 Dallas Avenue
                                                      Houston, Texas 77002

                  D. Page                             811 Dallas Avenue
                                                      Houston, Texas 77002

                  K. S. Hood                          811 Dallas Avenue
                                                      Houston, Texas 77002

                  5B. The name and mailing address of each person, who is to
serve as a director until the first annual meeting of the stockholders or until
a successor is elected and qualified, is as follows:
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                      NAME                                  MAILING ADDRESS
                      ----                                  ---------------

                  Bruce H. Whitehead                  5950 Berkshire, Suite 1100
                                                      Dallas, Texas 75225

                  Rudy Michalek                       5950 Berkshire, Suite 1100
                                                      Dallas, Texas 75225

                  Dale Patterson                      5950 Berkshire, Suite 1100
                                                      Dallas, Texas 75225

                  Vicki Lund                          5950 Berkshire, Suite 1100
                                                      Dallas, Texas 75225

                  Terri Sharp                         5950 Berkshire, Suite 1100
                                                      Dallas, Texas 75225

                  6. The corporation is to have perpetual existence.

                  7. In furtherance and not in limitation of the powers
conferred by statute, the board of directors is expressly authorized to make,
alter or repeal the by-laws of the corporation.

                  8. Elections of directors need not be by written ballot unless
the by-laws of the corporation shall so provide.

                  Meetings of stockholders may be held within or without the
State of Delaware, as the by-laws may provide. The books of the corporation may
be kept (subject to any provision contained in the statutes) outside the State
of Delaware at such place or places as may be designated from time to time by
the board of directors or in the by-laws of the corporation.

                  Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this corporation under
the provision of Section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this corporation under the provisions of Section 279 of Title 8 of the
Delaware Code order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this corporation, as the case may
be, to be summoned in such manner as the said court directs. If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this corporation as consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on all the
stockholders or class of stockholders, of this corporation, as the case may be,
and also on this corporation.
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                  9. The corporation reserves the right to amend, alter, change
or repeal any provision contained in this Certificate of Incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

                  10. A director of the corporation shall not be personally
liable to the corporation or its stockholders for monetary damages for breach of
fiduciary duty as a director except for liability (i) for any breach of the
director's duty of loyalty to the corporation or its stockholders, (ii) for acts
or omissions not in good faith or which involve intentional misconduct or a
knowing violation of law, (iii) under Section 174 of the Delaware General
Corporation Law, or (iv) for any transaction from which the director derived any
improper personal benefit.

                  WE, THE UNDERSIGNED, being each of the incorporators
hereinbefore named, for the purpose of forming a corporation pursuant to the
General Corporation Law of the State of Delaware, do make this certificate,
hereby declaring and certifying that this is our act and deed and the facts
herein stated are true, and accordingly have hereunto set our hands this 4th day
of August, 1992.

                                    /s/
                                    ----------------------------------
                                    L. B. Rush

                                    /s/
                                    ----------------------------------
                                    D. Page

                                    /s/
                                    ----------------------------------
                                    K. S. Hood