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                                                                    Exhibit 2.2


                              AMENDED AND RESTATED
                                     BYLAWS
                                       of

                  PENNSYLVANIA PHYSICIAN HEALTHCARE PLAN, INC.


                             Adopted October 3, 1998


                               ARTICLE I - OFFICES

                  1.1  Offices.  The  Corporation  may have such  offices as the
board of  directors  may from  time to time  determine  or the  business  of the
Corporation may require.


                                ARTICLE II - SEAL

                  2.1 Corporate  Seal.  The corporate  seal shall have inscribed
thereon the name of the Corporation,  the year of its organization and the words
"Corporate Seal, Pennsylvania".


                      ARTICLE III - SHAREHOLDERS' MEETINGS

                  3.1   Location   of   Shareholders'   Meetings.   Meetings  of
shareholders  shall be held at the  registered  office of the  Corporation or at
such other place as shall be determined by the board of directors.

                  3.2  Annual   Meeting.   The  annual  meeting  of  the  voting
shareholders shall be held each year on such date and at such time between March
1 and June 30 as shall be  determined  by the board of directors for the purpose
of electing  directors and for the  transaction of such other business as may be
properly  brought  before  the  meeting.  In each  election  of  directors,  the
candidates  receiving the highest number of votes, up to the number of directors
to be elected in such election, shall be elected.

                  3.3      Quorum.  The presence, in person or by proxy, of
shareholders entitled to cast at least one-third (1/3) of the votes


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which all  shareholders  are  entitled to cast on the  particular  matter  shall
constitute a quorum for the purpose of considering such matter. The shareholders
present  at  a  duly  organized  meeting  can  continue  to  do  business  until
adjournment, notwithstanding the withdrawal of enough shareholders to leave less
than a quorum.

                  3.4  Action by  Shareholders.  Except as  otherwise  specified
herein or  provided  by law,  whenever  any action is to be taken by vote of the
shareholders,  it shall be authorized upon receiving the  affirmative  vote of a
majority of the votes cast by all shareholders entitled to vote thereon.

                  3.5  Vote for Sale of  Corporation.  Any vote of  shareholders
having the effect of the acquisition of substantially the entire business of the
Corporation by any person,  whether a plan of merger,  sale or other disposition
of all or  substantially  all  the  assets,  or  otherwise,  shall  require  the
affirmative  vote of ninety percent  (90%)of the votes cast by all  shareholders
entitled to vote thereon.

                  3.6 Notice of Meetings. Written notice of every meeting of the
shareholders  shall be given to each  shareholder of record  entitled to vote at
the  meeting  at least ten days  prior to the day named for a meeting  called to
consider a fundamental  change under Chapter 19 of the Business  Corporation Law
of 1988,  as  amended,  or at least  five days  prior to the day named for other
meetings,  unless a greater period of notice is required in a particular case by
law.

                  3.7  Adjourned  Meetings.  When a meeting of  shareholders  is
adjourned, it shall not be necessary to give any notice of the adjourned meeting
or of the  business to be  transacted  at an  adjourned  meeting,  other than by
announcement at the meeting at which the adjournment is taken,  unless the board
of directors fixes a new record date for the adjourned meeting.

                  3.8  Judges  of  Election.   In  advance  of  any  meeting  of
shareholders,  the board of directors may appoint  judges of election,  who need
not be  shareholders,  to act at such  meeting or any  adjournment  thereof.  If
judges of  election  are not so  appointed,  the  presiding  officer of any such
meeting may, and on

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the request of any shareholder shall, make such appointment at the meeting.  The
number of judges shall be one or three.  No person who is a candidate for office
shall act as a judge.  The judge[s] of election may rely upon a certification by
the  shareholder  of record,  in a form  determined  by the  Corporation,  as to
whether the holder of any share of stock  eligible to vote at the meeting  meets
the voting eligibility  requirements set forth in the Corporation's  Articles of
Incorporation, as amended.

                  3.9 Special  Meetings.  Except as  otherwise  provided by law,
special  meetings  of  shareholders  may be called by and held at such places as
shall  be fixed by the  Chairman,  President  or the  board  of  directors.  The
Secretary of this Corporation shall, within three business days after receipt of
a written request by persons who have duly called such meeting,  fix the time of
the  meeting,  which  shall be held not more than 60 days  after  receipt of the
request,  and the  Secretary or the President  shall give notice  thereof to the
shareholders.  If the Secretary neglects or refuses,  within such three business
days  to fix the  time of the  meeting,  then  the  President  or the  board  of
directors may do so.

                  3.10 Record Date.  The books of the  Corporation  shall not be
closed against transfers of shares. The record date for determining shareholders
for any purpose  where such date has not been fixed by the board of directors or
by law,  shall be at the  close of  business  on the day on which  the  board of
directors adopts the resolution relating thereto.

                  3.11 Voting  Eligibility.  Only those persons eligible to hold
stock of the  Corporation,  as set forth in the  Articles of  Incorporation  and
Article XIII of these bylaws shall be eligible to receive notice and vote at any
shareholders' meeting.


                             ARTICLE IV - DIRECTORS

                  4.1 Number of Directors;  Election; Term. The business of this
Corporation  shall be managed by a board of  directors,  consisting  of not less
than 15 in  number.  All  directors  shall be  natural  persons  of full age.  A
director need not be a shareholder of the Corporation. At least two-thirds (2/3)
of the  directors  must be  actively  practicing  medical  doctors or doctors of
osteopathy. The directors shall be classified with respect to the time for

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which they shall  severally hold office by dividing them into three (3) classes,
as nearly equal in number as possible.  At each annual meeting of  shareholders,
the  successors to the class of directors  whose term expires that year shall be
elected to hold  office for terms of three (3) years,  and until the  director's
successor  shall have been  elected and  qualified,  or the  director's  earlier
resignation  or  removal.   The  number  of  directors  to  be  elected  by  the
shareholders  in any year  shall be  determined  by the Board of  Directors  and
specified in the notice of the annual meeting.  Within the limits stated in this
paragraph,  the number of directors may be increased at any time by the board of
directors.

                  4.2 Quorum.  One-third  (1/3) of the directors in office shall
be necessary to constitute a quorum for the transaction of business and the acts
of a majority of the directors present at a meeting at which a quorum is present
shall be the acts of the board of directors.

                  4.3 Regular and Special Meetings-Timing,  Location and Notice.
Regular and special  meetings  of the board of  directors  shall be held at such
times and places as shall be fixed by the board of directors.  Special  meetings
may be called by the President or Chairman of the Board of Directors.  Notice of
every special  meeting of the board of directors shall be given to each director
by  telephone  or in  writing  at  least  24 hours  (in the  case of  notice  by
telephone,  telex,  TWX or  telecopy)  or 48  hours  (in the case of  notice  by
telegraph,  courier  service or  express  mail) or five (5) days (in the case of
notice by first class mail)  before the time at which the meeting is to be held.
Neither  the  business to be  transacted  at, nor the purpose of, any regular or
special meeting of the board need be specified in the notice of the meeting.

                  4.4  Committees  Generally.  The board of  directors  may,  by
resolution  adopted by a majority of the  directors in office,  establish one or
more committees,  in addition to those  established  under the Bylaws at Section
4.6  below,  each  committee  to  consist  of one or  more of the  directors.  A
committee,  to the extent  provided in the  resolution of the board of directors
creating it, shall have and may exercise all of the powers and  authority of the
board of directors except that a committee shall not have any power or authority
regarding:  (i) the  submission  to  shareholders  of any action  requiring  the
approval of shareholders under the

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Pennsylvania  Business Corporation Law of 1988, as amended, (ii) the creation or
filling of vacancies in the board of directors, (iii) the adoption, amendment or
repeal of the bylaws,  (iv) the amendment,  adoption or repeal of any resolution
of the board that by its terms is amendable or repealable  only by the board, or
(v) action on matters  committed  by the  bylaws or  resolution  of the board to
another committee of the board. The board may designate one or more directors as
alternate  members of any committee  who may replace any absent or  disqualified
member at any meeting of the committee or for the purposes of any written action
by the committee.  In the absence or  disqualification of a member and alternate
member or members of a committee,  the member or members  thereof present at any
meeting and not disqualified from voting,  whether or not constituting a quorum,
may unanimously  appoint another  director to act at the meeting in the place of
the absent or  disqualified  member.  Each committee of the board shall serve at
the pleasure of the board.

         4.5  Committee  Procedures.  The term "board of  directors" or "board,"
when used in any  provision  of these  Bylaws  relating to the  organization  or
procedures of or the manner of taking action by the board of directors, shall be
construed to include and refer to any executive or other committee of the board.
The board of directors  shall  appoint one member of each  committee to serve as
chairman of that  committee.  Each chairman shall preside at all meetings of his
or her committee.

         4.6      Specific Committees.

                  4.6.1.  Executive Committee

         Among other duties  assigned to it by Board  resolution,  the Executive
Committee  shall have and may exercise all the powers and authority of the Board
of Directors between meetings of the Board of Directors, except as restricted by
Section 4.4 of these bylaws, or as otherwise restricted by law.

                  4.6.2.  Audit Committee

         The Audit Committee, to the extent permitted by law or regulation
applicable to the Corporation, shall recommend the firm to be employed as the
Corporation's independent auditor, and review and approve the discharge of any
such firm. The Audit Committee

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shall also review and approve the independent auditor's compensation,  the terms
of its engagement,  and the  independence  of such auditor.  The Audit Committee
shall, in consultation with the independent auditor:  review the results of each
external  audit  of the  Corporation,  the  report  of the  audit,  any  related
management  letter and  management's  responses to  recommendations  made by the
independent  auditor in  connection  with the audit,  the  Corporation's  annual
financial statements, any certification,  report, opinion, or review rendered by
the independent auditor in connection with those financial  statements,  and any
significant  disputes between management and the independent  auditor that arose
in  connection  with  the  preparation  of  those   financial   statements.   In
consultation with the independent  auditor,  the  Corporation's  chief financial
officer  and the chief  internal  auditor,  if any,  the Audit  Committee  shall
consider the adequacy of the  Corporation's  internal audit controls.  The Audit
Committee  shall also consider,  when presented by the  independent  auditor,  a
principal  senior  executive,  or otherwise,  material  questions of choice with
respect to the appropriate  auditing and accounting  principles and practices to
be used in the preparation of the Corporation's financial statements.


          ARTICLE V - ACTION BY WRITTEN CONSENT AND USE
                      OF CONFERENCE TELEPHONE

                  5.1 Actions by Unanimous Written Consent.  Any action required
or permitted to be taken at any meeting of the shareholders or the directors, or
of any  committee  of  directors,  may be taken  without a meeting if,  prior or
subsequent to the action, a consent or consents thereto in writing setting forth
the action so taken is signed by all the  shareholders  who would be entitled to
vote at a meeting for such purpose,  or by all of the directors in office, or by
all of the members of such committee in office, as the case may be, and is filed
with the Secretary of the Corporation.

                  5.2 Participation in Meetings by Conference Telephone.  One or
more persons may participate in a meeting of the shareholders, of the directors,
or of any  committee of directors,  by means of conference  telephone or similar
communications  equipment  by means of which all  persons  participating  in the
meeting can hear each other.  Such  participation  shall constitute  presence in
person at the meeting.

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                              ARTICLE VI - OFFICERS

                  6.1 Officers;  Term.  The  Corporation  shall have a Chairman,
President,  Secretary,  and  Treasurer  and such other  officers  and  assistant
officers as the board of directors  shall  authorize from time to time who shall
be elected or appointed by the board of directors each to serve for such term as
shall be determined by the board of directors, and until his or her successor is
chosen and shall  have  qualified  or until his or her  earlier  resignation  or
removal. Any of the foregoing offices may be held by the same person.

                  6.2 Authority and Duties of Officers.  The officers shall have
such  authority  and  perform  such  duties  customarily  associated  with their
respective  offices  unless the board of directors  shall  determine  otherwise.
Unless otherwise determined by a resolution of the board of directors, the Board
shall also fix the compensation of all officers of the Corporation.

                  6.3 Removal.  Any officer or agent elected or appointed by the
board of  directors  may be  removed by the board of  directors  with or without
cause,  without  prejudice  to the  contract  rights,  if any,  of the person so
removed.


                        ARTICLE VII - SHARE CERTIFICATES

                  7.1 Execution of Share  Certificates.  Every share certificate
shall be executed by facsimile or otherwise, by or on behalf of the Corporation,
by the Chairman or President and  countersigned by the Treasurer or an Assistant
Treasurer  or by the  Secretary  or an  Assistant  Secretary.  In the  event any
officer who has signed,  or whose  facsimile  signature has been placed upon any
share  certificate  shall have ceased to be such officer because of resignation,
removal or otherwise,  before the certificate is issued, it may be issued by the
Corporation  with the same effect as if the officer had not ceased to be such at
the date of issue.

                  7.2      Transfers of Shares.  Transfers of shares shall be
made on the books of the Corporation upon surrender of the
certificates therefor, endorsed by the person named in the

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certificates.  No  transfer  shall  be made in a  manner  inconsistent  with the
provisions of Article VIII of the Pennsylvania  Uniform  Commercial Code and its
amendments and supplements.

                  7.3 Lost Certificates. Any person claiming a share certificate
to be lost or destroyed shall be issued a new certificate  after  furnishing the
Corporation with a satisfactory affidavit that such certificate has been lost or
destroyed,  and, if required by the board of  directors,  a bond of indemnity to
the  Corporation  with  satisfactory  surety to protect the  Corporation  or any
person injured by the issue of a new  certificate  from any liability or expense
by reason thereof.


                                   ARTICLE VIII - INDEMNIFICATION AND LIMITATION
                         OF DIRECTOR LIABILITY

                  8.1  Indemnification.  Any  person who was or is a party or is
threatened to be made a party to any threatened,  pending or completed action or
proceeding, whether civil, criminal, administrative or investigative (whether or
not the  liability  arises or arose from any  threatened,  pending or  completed
action  by or in the  right of the  Corporation)  by reason of the fact that the
person  at  any  time  is or  shall  have  been a  director  or  officer  of the
Corporation or any of its subsidiaries,  or is or shall have been serving at the
written request of the Corporation as a director,  officer, employee or agent of
another Corporation, for profit or not-for-profit,  partnership,  joint venture,
trust  or  other   enterprise,   and  such   person's   heirs,   executors   and
administrators,  shall be indemnified by the Corporation,  to the fullest extent
permitted by applicable  law,  against  expenses  (including  attorney's  fees),
judgments, fines and amounts paid in settlement actually and reasonably incurred
by such person in connection  with such action or  proceeding  unless the act or
failure to act giving rise to the claim for  indemnification  is  determined  to
have constituted  willful  misconduct or recklessness.  The  determination  that
indemnification  shall be made because such standard of conduct has been met may
be made by a court, or in the absence of a court determination, shall be made by
the board by a majority vote of any directors who were not parties to the action
or  proceeding,  even though such  directors  are less than a quorum,  or, if no
directors are disinterested, by independent legal counsel in a written opinion.

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                  8.2 Advancing Expenses.  Expenses (including  attorneys' fees)
incurred in defending any action or proceeding  referred to in Section 8.1 shall
be paid by the Corporation in advance of the final  disposition of the action or
proceeding  upon receipt of an  undertaking  by or on behalf of the person to be
indemnified to repay the amount if it is ultimately determined that he or she is
not entitled to be indemnified by the  Corporation as authorized by these bylaws
or otherwise.

                  8.3 Contract  Right.  The right of a person covered by Section
8.1 hereof to be indemnified or to receive an  advancement or  reimbursement  of
expenses  pursuant  to Section 8.2 hereof (1) may also be enforced as a contract
right  pursuant  to which the person  entitled  thereto may bring suit as if the
provisions  hereof  were set forth in a separate  written  contract  between the
Corporation and such person,  and (2) shall continue to exist, if this Article 8
is  rescinded  or  restrictively  modified,  with  respect  to  events,  acts or
omissions  occurring  before such  rescission  or  restrictive  modification  is
adopted.

                  8.4 Non-Exclusivity of Indemnification; Insurance. The
foregoing right of indemnification shall not be deemed exclusive of other rights
to which any director, officer, employee, agent or other person may be entitled
in any capacity as a matter of law or under any bylaw, agreement, vote of
directors, or otherwise. The Corporation may purchase and maintain insurance on
behalf of any person to the full extent permitted by Pennsylvania law as in
effect at the adoption of this bylaw or as amended from time to time. The
Corporation may create a fund of any nature which may, but need not be, under
the control of a trustee, or otherwise secure or insure in any manner its
indemnification obligations under this bylaw.

                  8.5 Limitation of Director  Liability.  Each person who at any
time  is or  shall  have  been a  director  of  this  Corporation  shall  not be
personally  liable for  monetary  damages as such for any action  taken,  or any
failure to take any action,  unless: (1) such person as director has breached or
failed to perform the duties of his office under 15 Pa. C.S. Subchapter 17B, and
(2)  the  breach  or  failure  to  perform  constitutes  self  dealing,  willful
misconduct or recklessness. The provisions of this bylaw shall not apply to: (1)
responsibility or liability of such person as director pursuant to

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any criminal  statute;  or (2) the  liability of a director for payment of taxes
pursuant to local,  state or federal law. The  provisions of this bylaw shall be
construed to limit the liability of such person as director in  accordance  with
and to the full extent permitted by Pennsylvania law as in effect at the time of
the adoption of this bylaw or as amended from time to time.


                               ARTICLE IX - NOTICE

                  9.1 Manner of Giving Notice. Except as otherwise  specifically
provided in these bylaws,  whenever the  Corporation is required to give written
notice to any person under these  bylaws or by statute,  it may be given to such
person, either personally or by sending a copy thereof by first class or express
mail, postage prepaid, or by telegram (with messenger service specified),  telex
or TWX (with  answerback  received),  courier service (charges  prepaid),  or by
telecopier  to his or her address (or to his or her telex,  TWX,  telecopier  or
telephone  number)  appearing on the books of the Corporation or, in the case of
directors,  supplied  by the  directors  to the  Corporation  for the purpose of
notice. If the notice is sent by mail, telegraph or by courier service, it shall
be deemed to have been given to the person entitled thereto one (1) business day
after being  deposited in the United States mail, with a courier service or with
a telegraph  office for delivery to such person or, in the case of telex, TWX or
telecopy, when dispatched.  Such notice shall specify the place, day and hour of
the meeting and, in the case of a special meeting of  shareholders,  the general
nature of the business to be transacted.


                             ARTICLE X - AMENDMENTS

                  10.1  Amendments  to Bylaws.  Except as otherwise  provided in
this Section 10.1, the bylaws of the Corporation may be amended or repealed by a
majority  vote of the  members  of the  board  of  directors,  unless  otherwise
provided by law,  subject  always to the power of the  shareholders  entitled to
vote to change such action.  Notwithstanding  the  foregoing or any of the other
provisions  of these  Bylaws,  Section  3.5 of the  Bylaws may not be amended or
repealed except by an affirmative  vote of ninety percent (90%)of the votes cast
by all shareholders entitled to vote thereon.


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                            ARTICLE XI - FISCAL YEAR

                  11.1 Fiscal Year. The fiscal year of the Corporation  shall be
fixed by the board of directors.


                        ARTICLE XII - CORPORATE DIVISION

                  12.1 Plan of  Division.  Any plan of  division  shall  require
approval  of the  shareholders,  in the manner  provided  in Section 3.4 hereof,
notwithstanding  any provision in the Pennsylvania  Business  Corporation Law of
1988, as amended, to the contrary.


             ARTICLE XIII - SHAREHOLDER ELIGIBILITY; SHARE TRANSFERS

                  13.1  Shareholder  Eligibility.  The following person shall be
eligible to acquire and hold stock of the Corporation of record:

                           (i)      any health professional licensed in
                                    Pennsylvania or elsewhere;

                           (ii)     any retired, but formerly licensed, health
                                    professional;

                           (iii)    any professional corporation or other 
                                    practice group of health professionals;

                           (iv)     any individual  retirement  account or other
                                    retirement  plan  established  by  a  person
                                    eligible  to be a  shareholder  or in  which
                                    such person is a participant; and

                           (v)      any employee of the Corporation.

As used herein the term "health professional" shall include, without limitation:
physicians,  podiatrists, dentists, oral surgeons, optometrists,  chiropractors,
nurses, nurse practitioners,  physical or occupational  therapists,  physicians'
assistants.


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                  13.2  Share Transfers.

                           13.2.1  A shareholder of record may not voluntarily
transfer for value any share of the  Corporation  except to a transferee who, in
accordance  with the  provisions  of the  Articles  of  Incorporation  and these
bylaws, is a shareholder of record and who is entitled to vote such share.

                           13.2.2  The Corporation may rely upon a
certification of the transferee, in a form determined by the
Corporation, to establish the voting eligibility of the transferee.

                           13.2.3  For purposes of this Section, "voluntary
transfer for value" shall not include  gifts,  transfers by operation of law, or
any other involuntary transfer or involuntary disposition.




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