Exhibit 10.86

                               GUARANTY AGREEMENT


         This Guaranty  Agreement dated as of August 31,  1999 (as amended or
otherwise modified from time to time, this "Guaranty") is by FemPartners,  Inc.,
a Delaware  corporation  ("Guarantor") in favor of American  Physicians  Service
Group, Inc., a Texas corporation ("Lender").

         WHEREAS,   (i)  Lender,   Syntera  HealthCare   Corporation,   a  Texas
corporation  ("Syntera"),  Guarantor and  FemPartners of Central Texas,  Inc., a
Delaware corporation and wholly-owned  subsidiary of Guarantor  ("Obligor") have
entered  into an  Agreement  and Plan of Merger of even  date  herewith  whereby
Syntera  is merging  with and into  Obligor  with  Obligor  being the  surviving
corporation,  (ii) certain debt owing to Lender from Syntera is evidenced by the
Promissory Note dated November 1, 1998, and is being contemporaneously  amended,
restated and replaced in its entirety by the  Replacement  Promissory Note dated
of even date herewith (as may be amended and or otherwise  modified from time to
time, the "Note"), (iii) Guarantor will directly and indirectly benefit from the
Note,  and (iv) as a condition  precedent to the  consummation  of the merger of
Syntera into Obligor, Lender has required that Guarantor guarantee to Lender all
payment obligations of Obligor under the Note.

         NOW THEREFORE, Guarantor agrees with Lender as follows:

         1.   PAYMENT   GUARANTY.   Guarantor   absolutely,    irrevocably   and
unconditionally  guarantees  to  Lender,  and  to  its  successors,   endorsees,
transferees and assigns,  the prompt and complete  payment when due,  whether at
the stated maturity, by acceleration or otherwise, of the obligations of Obligor
set forth in the Note (collectively,  the "Obligations").  No termination of the
Note shall affect any  obligations  incurred by Guarantor under this Guaranty at
the time of termination.  No notice of the Obligations need be given in any form
to Guarantor at any time and  Guarantor  waives any such notice and the right to
consent to the Obligations. Guarantor waives any right to require as a condition
to its obligations hereunder that collateral be applied to the Obligations, that
presentment  or demand be made upon  Obligor or that  action be brought  against
Obligor or any other person or entity  except  Guarantor,  should Lender seek to
enforce  the  obligations  of  Guarantor.   Specifically,   without  limitation,
Guarantor  waives any right to require  that a judgment  previously  be rendered
against Obligor or any other person or entity except Guarantor,  that Obligor or
any other person or entity be joined in any action against  Guarantor or that an
action  separate from one against  Guarantor be brought  against  Obligor or any
other person or entity.  The  obligations of Guarantor are several from those of
Obligor  or any other  person or entity,  and are  primary  payment  obligations
concerning which Guarantor is the principal  obligor.  If all or any part of the
Obligations are not paid when due,  Guarantor hereby guarantees that it will pay
the same to Lender,  upon demand,  without set-off or  counterclaim  and without
reduction by reason of any taxes,  levies,  imposts,  charges and  withholdings,
restrictions  or  conditions  of any  nature  that are now or may  hereafter  be
imposed,  levied or assessed by any  country,  political  subdivision  or taxing
authority,  all of which will be for the account of and paid by  Guarantor,  and
Lender need not first proceed to preserve, utilize or exhaust any other right or
remedy  against  Obligor,  any  other  guarantor,  any  collateral  or any other
security  that  Lender  may have in  order  to  obtain  payment  hereunder.  The
obligations  of Guarantor  hereunder  shall in no way be affected or impaired by
reason  of the  happening  from  time  to  time  of any  of the  following:  (i)
extensions  (whether  or not  material)  of the time for  payment  of all or any

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portion of the  Obligations,  (ii) the  modification  or amendment in any manner
(whether  or not  material)  of the Note or the  Obligations,  (iii)  except for
applicable statutes of limitations,  any failure,  delay or lack of diligence on
the part of Lender, or any other person or entity to enforce, assert or exercise
any right, privilege, power or remedy conferred on Lender or any other person or
entity in the Note or at law,  or any action on the part of Lender or such other
person  or  entity  granting  indulgence  or  extension  of any  kind,  (iv) the
settlement  or compromise of any  Obligations  and (v) the status,  composition,
structure or name of Obligor change, including, without limitation, by reason of
merger,  dissolution,  consolidation  or  reorganization.   NOTWITHSTANDING  THE
FOREGOING,  THE  LIABILITY  OF GUARANTOR  HEREUNDER  SHALL BE LIMITED TO DIRECT,
ACTUAL  DAMAGES  AND  GUARANTOR  SHALL NOT BE LIABLE  UNDER  THIS  GUARANTY  FOR
CONSEQUENTIAL, INCIDENTAL, PUNITIVE, EXEMPLARY OR INDIRECT DAMAGES, LOST PROFITS
OR OTHER BUSINESS INTERRUPTION DAMAGES, IN TORT, CONTRACT OR OTHERWISE.  Upon 30
Days written notice and with the prior written consent of Lender,  which consent
shall not be  unreasonably  withheld,  this  Guaranty  may be  replaced by (x) a
guaranty in  substantially  similar  form made by a guarantor of equal or better
creditworthiness  or (y) a letter of credit in favor of Lender in the  amount of
the maximum Limit (below defined), issued by a bank and in a form, each of which
shall be reasonably satisfactory to Lender.

         2.       COSTS AND  EXPENSES. In addition to its guarantee of Obligor's
payment of the  Obligations,  Guarantor  shall pay all actual costs and expenses
(including  reasonable attorney's fees) paid or incurred by Lender in connection
with the enforcement of this Guaranty.

         3. CONTINUING  GUARANTY.  This is intended to be and shall be construed
as a continuing guarantee and shall remain in full force and effect and shall be
binding in accordance with and to the extent of its terms upon Guarantor and its
successors  and  assigns,  and shall  inure to the  benefit of  Lender,  and its
successors,  endorsees,  transferees  and assigns.  The obligations of Guarantor
under this Guaranty  shall continue in full force and effect and shall remain in
operation until all of the Obligations shall have been paid in full or otherwise
fully satisfied, and continue to be effective or be reinstated,  as the case may
be, if at any time payment or other  satisfaction  of any of the  Obligations is
rescinded  or must  otherwise  be  restored  or  returned  upon the  bankruptcy,
insolvency,  or reorganization of Obligor, or otherwise,  as though such payment
had not been made or other satisfaction occurred. No invalidity, irregularity or
unenforceability  by reason of applicable  bankruptcy  laws or any other similar
law, or any law or order of any  government or government  agency  purporting to
reduce, amend or otherwise affect, the Obligations,  shall impair,  affect, be a
defense to or claim against the obligations of Guarantor under this Guaranty.

         4.  SUBROGATION.  Notwithstanding  any  payment  or  payments  made  by
Guarantor under this Guaranty or any setoff or application of funds of Guarantor
by Lender, Guarantor shall not be entitled to be subrogated to any of the rights
of Lender  against  Obligor or any  collateral or other security or guarantee or
right  of  offset  held  by  Lender  for  the  payment  or  performance  of  the
Obligations,  nor shall Guarantor seek any reimbursement from Obligor in respect
of payments made by Guarantor under this Guaranty,  until all amounts then owing
and any other performance then due to Lender by Obligor for or on account of the

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Obligations are paid and satisfied in full.  Upon such payment and  satisfaction
in full,  Guarantor  shall be subrogated to all rights of Lender against Obligor
or any  collateral  or other  security or  guarantee  or right of offset held by
Lender for the payment and performance of the Obligations.

         5. SUBORDINATION.  Any and all indebtedness of Obligor now or hereafter
owed to or held by Guarantor is hereby  subordinated  to the Obligations and all
other  indebtedness  of Obligor to Lender;  and such  indebtedness of Obligor to
Guarantor, if Lender so requests,  shall be collected,  enforced and received by
Guarantor  as  trustee  for  Lender and be paid over to Lender on account of the
indebtedness  of Obligor to Lender but  without  reducing  or  affecting  in any
manner the liability of Guarantor under the other provisions of this Guaranty.

         6. DEFAULT.  If Obligor fails or refuses to timely pay any Obligations,
Lender may at its option exercise any or all of its rights,  powers and remedies
afforded  hereunder and may declare the unpaid amounts of all  Obligations  then
owing under the Note to be  immediately  due and  payable,  and  thereupon  such
amounts shall be immediately due and payable without presentation and demand for
payment,  protest,  notice of protest or dishonor,  notice of default, notice of
intent to accelerate or notice of  acceleration to Guarantor or any other person
or entity, all of which Guarantor waives.

         7. NO WAIVER. No failure to exercise and no delay in exercising, on the
part of Lender,  any right, power or privilege under this Guaranty shall operate
as a waiver of the right,  power or  privilege,  nor shall any single or partial
exercise of any right, power or privilege preclude any other or further exercise
of the right,  power or privilege,  or the exercise of any other power or right.
The rights  and  remedies  provided  in this  Guaranty  are  cumulative  and not
exclusive of any rights or remedies provided by law.

         8. NOTICE.  All notices and  communications  made pursuant to this
Guaranty  shall be in writing and  delivered  personally  or mailed by certified
mail,  postage prepaid and return receipt  requested,  or sent by facsimile,  as
follows:

         To Guarantor:
         ------------

         FemPartners, Inc.
         1300 Post Oak Blvd., Suite 600
         Houston, Texas    77056
         Attn.:   Jack Thompson
         Facsimile: (713) 512-8080

         To Lender:
         ---------

         American Physicians Service Group, Inc.
         1301 Capital of Texas Highway, Suite C-300
         Austin, Texas   78746-6550
         Attn:  Colleen Webb
         Facsimile:  (512) 314-4333



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Notice given by person, delivery or mail shall be effective upon actual receipt.
Notice given by facsimile  shall be  effective  upon actual  receipt if received
during recipient's normal business hours or at the beginning of recipient's next
business day after receipt if not received  during  recipient's  normal business
hours. Any party may change its address to which notice is to be given hereunder
by providing notice of same in accordance with this Section 8.

         9.  MISCELLANEOUS.  THIS GUARANTY SHALL IN ALL RESPECTS BE GOVERNED BY,
AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF TEXAS, WITHOUT REGARD
TO  PRINCIPLES  OF CONFLICTS OF LAWS.  Guarantor  waives notice of acceptance of
this Guaranty. No term or provision of this Guaranty shall be amended, modified,
altered,  waived,  supplemented or terminated  except in a writing signed by the
parties hereto.  This Guaranty shall be binding upon and inure to the benefit of
an be  enforceable  by the  respective  successors  and assigns of Guarantor and
Lender.  This Guaranty embodies the entire agreement and  understanding  between
Guarantor and Lender and  supersedes  all prior  agreements  and  understandings
relating to the subject  matter  hereof.  The headings in this  Guaranty are for
purposes  of  reference  only,  and shall not affect the  meaning  hereof.  This
Guaranty may be executed in any number of  counterparts,  each of which shall be
an original, but all of which together shall constitute one document.

         IN WITNESS WHEREOF,  the Guarantor has executed this Guaranty Agreement
on the date first above written.

                                         FEMPARTNERS, INC.


                                         By:  /s/ William C. Altman
                                              -----------------------
                                              William C. Altman
                                              Executive Vice President