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                                                                   Exhibit 10.28
                            SECURED PROMISSORY NOTE
                                   (RENEWAL)

$13,739,693.87                                                 November 12, 1997
                                                                   Dallas, Texas

     FOR VALUE RECEIVED, this Secured Promissory Note (this "Note") is made by
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JAYHAWK MEDICAL ACCEPTANCE CORPORATION, a Texas corporation ("Maker"), to CARL
H. WESTCOTT ("Payee").

     1.   Payments.  Maker hereby promises to pay to the order of Payee the
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principal sum of THIRTEEN MILLION SEVEN HUNDRED THIRTY-NINE THOUSAND SIX HUNDRED
AND NINETY-THREE DOLLARS AND EIGHTY-SEVEN CENTS ($13,739,693.87) at his address
at 100 Crescent Court, Suite 1620, Dallas, Texas 75201, or such other place as
the holder hereof may designate from time to time in writing, in lawful money of
the United States of America and in immediately available funds, together with
interest on the unpaid principal balance hereof at the rate provided herein from
the date of this Note until payment in full of the indebtedness evidenced by
this Note.  The principal amount of this Note outstanding shall be due and
payable in one lump sum payment of the outstanding principal balance on November
12, 1999 (the "Maturity Date").  Interest on the outstanding principal balance
hereunder shall accrue from the date of this Note until paid and all accrued and
unpaid interest shall be due and payable by Maker to Payee on the Maturity Date.

     2.   Final Payment.  On the Maturity Date, all amounts hereunder shall
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immediately become due and payable without demand or notice.  All payments
received by Payee after the Maturity Date (whether of principal, interest or
other amounts) which are applied at any time by Payee to indebtedness evidenced
by this Note may be allocated, applied and reapplied by Payee to principal,
interest or other amounts then due and payable as Payee may determine in Payee's
sole discretion.

     3.   Interest Rate.  The principal amount outstanding from time to time
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hereunder shall bear interest calculated daily on the basis of a 360-day year,
at a rate equal to the Prime Rate.  As used herein, the term "Prime Rate" shall
mean the prime rate of interest per annum of NationsBank Texas, N.A., as
determined from time to time by NationsBank Texas, N.A. as its prime rate of
interest, fluctuating upward or downward on the business day of each such
determination.

     4.   Maximum Rate.  It is the intention of the Maker and Payee to conform
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strictly to any usury laws in force that apply to this transaction.
Accordingly, all agreements among the parties hereto whether previously
existing, now existing or hereafter arising and whether written or oral, are
hereby limited so that in no contingency, whether by reason of acceleration of
the maturity of the amounts owing under this Note or otherwise, shall the
interest (and all other sums that are deemed to be interest) contracted for,
charged or received by Payee with respect to this Note, exceed the Highest
Lawful Rate.  The "Highest Lawful Rate" means the maximum nonusurious interest
rate that at any time or from time to time may be contracted for, taken,
reserved, charged or received under the laws of the United States and the laws
of such states as
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may be applicable thereto which are presently in effect or, to the extent
allowed under such applicable laws of the United States and the laws of such
states, which may hereafter be in effect and which allow a higher maximum
nonusurious interest rate than applicable laws now allow. If, from any
circumstance whatsoever, interest under any agreement to which Maker and Payee
are parties would otherwise be payable in excess of the Highest Lawful Rate, and
if from any circumstance Payee shall ever receive anything of value deemed
interest by applicable law in excess of the Highest Lawful Rate, then Payee's
receipt of such excess interest shall be deemed a mistake and the same shall, so
long as no Event of Default under this Note or the Security Agreement shall be
continuing, at the option of Maker, either be repaid to Maker or credited to the
unpaid principal; provided, however, that if an Event of Default shall have
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occurred and be continuing, and Payee shall receive excess interest during such
period, then Payee shall have the option of either crediting such excess amount
to principal or refunding such excess amount to Maker.  All interest paid or
agreed to be paid to Payee shall, to the extent allowed by applicable law, be
amortized, prorated, allocated, and spread throughout the full period of Maker's
credit relationship with Payee until payment in full of the principal (including
the period of any renewal or extension) so that the interest for such full
period shall not exceed the Highest Lawful Rate.

     5.   Prepayment.  This Note may be prepaid, in whole or in part, without
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premium or penalty.  All prepayments shall be applied first to accrued interest
and then to principal.

     6.   Default Rate.  Upon the failure of Maker to make any payment of
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principal or interest on, or any amount owing in respect of, the indebtedness
evidenced by this Note, or any other amounts payable by Maker to Payee pursuant
to the terms hereof or any other agreement, when due and payable or declared due
and payable, the interest rate applicable to this Note shall be increased by the
lesser of three percent (3%) per annum above the rate otherwise applicable or
the Highest Lawful Rate.

     7.   Security Agreement.  This Note, including the principal, interest and
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fees and costs payable pursuant hereto, is secured by, among other things, that
certain Security Agreement between Maker and Payee, dated as of March 6, 1997
(the "Security Agreement"), and all covenants, agreements and undertakings of
Maker set forth therein are incorporated in and made part of this Note with the
same force as if fully set forth herein.

     8.   Event of Default.  The occurrence of any one or more of the following
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shall constitute an "Event of Default" hereunder:

          (a) Maker shall fail to pay any principal, interest or other amounts
     when due and payable or declared due and payable (whether at maturity, by
     acceleration or otherwise) under this Note or under any other promissory
     note made by Maker in favor of Payee;

          (b) Maker shall fail or neglect to perform, keep or observe any
     provision, condition, covenant or warranty contained in this Note or in the
     Security Agreement (other than as set forth in paragraph 8(a) of this
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     Note);
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          (c) A judgment or judgments for the payment of money in excess of
     $50,000 in the aggregate shall be rendered against Maker and any such
     judgment or judgments shall, if unsatisfied, remain unstayed for a period
     in excess of thirty (30) days;

          (d) The Collateral (as defined in the Security Agreement) or any
     assets of Maker are attached, seized, levied upon or subjected to a writ or
     distress warrant, or come within the possession of any receiver, trustee,
     custodian or assignee for the benefit of creditors and the same is not
     cured within thirty (30) days thereafter; an application is made by any
     person, other than Maker, for the appointment of a receiver, trustee, or
     custodian for Maker's assets and the same is not dismissed within thirty
     (30) days after the application therefor;

          (e) An application is made by Maker for the appointment of a receiver,
     trustee or custodian for any of Maker's assets; a petition under any
     section or chapter of the Bankruptcy Code or any similar law or regulation
     shall be filed by Maker; or Maker shall make an assignment for the benefit
     of its creditors or any case or proceeding is filed by Maker for its
     dissolution, liquidation, or termination;

          (f) Maker shall be enjoined, restrained or in any way prevented by
     court order from conducting all or any material part of its business
     affairs; a petition under any section or chapter of the Bankruptcy Code or
     any similar law or regulation is filed against Maker or any case or
     proceeding is filed against Maker for its dissolution or liquidation, and
     such injunction, restraint or petition is not dismissed within thirty (30)
     days after the entry or filing thereof;

          (g) A notice of lien, levy or assessment is filed of record with
     respect to all or any of Maker's assets by the United States, or any
     department, agency or instrumentality thereof, or by any state, county,
     municipal or other governmental agency, including, without limitation, the
     Pension Benefit Guaranty Corporation, or if any taxes or debts owing at any
     time or times hereafter to any one of these becomes a lien or encumbrance
     upon any of Maker's assets and the same is not released within thirty (30)
     days after the same becomes a lien or encumbrance; or

          (h) Maker becomes insolvent or admits in writing its inability to pay
     its debts as they mature or communicates its intention to petition for
     protection under the Bankruptcy Code or apply for the appointment of a
     receiver, trustee or custodian.

     9.   Remedies.  Upon and after the occurrence and continuance of an Event
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of Default, Payee shall have the option, without demand or notice or legal
process of any kind, to declare the unpaid principal of this Note, together with
interest thereon and any other sums owing hereunder, at once due and payable,
and to exercise any and all other rights and remedies available hereunder or
under the Security Agreement, or otherwise available at law or in equity.

     10.  Remedies Cumulative.  The remedies of Payee, as provided herein, shall
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be cumulative and concurrent, and may be pursued singularly, successively or
together, at the sole
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discretion of Payee, and may be exercised as often as occasion therefor shall
arise. No act of omission or commission of Payee, including specifically any
failure to exercise any right, remedy or recourse, shall be deemed to be a
waiver or release of the same, such waiver or release to be effected only
through a written document executed by Payee and then only to the extent
specifically recited therein. A waiver or release with reference to any one
event shall not be construed as continuing, as a bar to, or as a waiver or
release of, any subsequent right, remedy or recourse as to a subsequent event.

     11.  Costs of Collection.  Maker promises to pay all of Payee's costs of
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collection of every kind, including but not limited to all reasonable attorneys'
fees, court costs, and expenses of every kind, incurred by Payee in connection
with the collection (including, but not limited to collection through a
bankruptcy or other court) or enforcement of this Note.  If Payee or its
affiliates advance any additional amounts to or on behalf of Maker, then the
principal amount of this Note may, at the option of Payee, be increased by the
amounts so advanced, and Maker agrees to repay such additional amounts pursuant
to the terms hereof.

     12.  Waivers.  Maker and each surety, endorser, guarantor and other party
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now or hereafter liable for the payment of any sums of money payable on this
Note, hereby severally (a) waive demand, presentment for payment, notice of
dishonor, notice of nonpayment, protest, notice of protest, notice of intent to
accelerate, notice of acceleration and all other notices, filing of suit and
diligence in collecting this Note or enforcing any other security with respect
to same, (b)  agree to any substitution, subordination, exchange  or release of
any such security or the release of any parties primarily or secondarily liable
hereon, (c) agree that Payee shall not be required first to institute suit or
exhaust its remedies hereunder against Maker, or others liable or to become
liable hereon or to enforce its rights against them or any security with respect
to same, (d) consent to any and all renewals, extensions, indulgences, releases
or changes regardless of the number of such renewals, extensions, indulgences,
releases or changes, without notice thereof, and (e) agree to the application of
any deposit balance with Payee as payment or part payment hereon or as an offset
hereto.  No such conduct shall affect, impair, release or change the liability
of Maker, surety, endorser, guarantor and any other party.  No waiver by Payee
of any of its rights or remedies hereunder or under any other document
evidencing or securing this Note or otherwise shall be considered a waiver of
any other subsequent right or remedy of Payee; no delay or omission in the
exercise or endorsement by Payee of any rights or remedies shall ever be
construed as a waiver of the same or any other right or remedy of Payee; and no
exercise or enforcement of any such right or remedy shall ever be held to
exhaust any right or remedy of Payee.

     13.  Modification, Extension and Renewal.  This Note is an amendment,
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restatement, extension and renewal of the aggregate principal amount of (i) that
certain promissory note dated February 11, 1997 in the original principal amount
of $1,050,000, (ii) that certain promissory note dated February 18, 1997 in the
original principal amount of $900,000, (iii) that certain promissory note dated
February 26, 1997 in the original principal amount of $1,000,000, (iv) that
certain promissory note dated March 4, 1997, in the original principal amount of
$1,000,000, (v) that certain promissory note dated March 10, 1997 in the
original principal amount of $1,000,000, and (vi) that certain promissory note
dated June 11, 1997 in the original principal amount, each of
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which was made by Maker to order of Payee, and the stated principal amount of
this Note includes all principal on such notes (but not accrued interest on such
notes) as of the date hereof, together with $6,489,693.87 of principal
(exclusive of accrued interest) due by Maker to Payee under that certain
promissory note dated October 1, 1996 made by Maker to the order of NationsBank
Texas, N.A., and subsequently assigned to Payee. Following the execution and
delivery of this Note, each of the foregoing notes shall be marked "modified,
extended and renewed" and shall be attached hereto. The collateral given under
the Security Agreement is not being released or modified. Further, while the
original principal amount hereunder does not include the interest accrued on the
prior notes being renewed and modified hereby, such accrued interest shall
remain due and owing under the terms of the prior notes and the obligation of
Maker to pay to Payee such accrued and unpaid interest shall remain secured
pursuant to the Security Agreement.

     14.  Notices.  Except as otherwise provided herein, any notice or demand
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which, by the provisions hereof, is required or which may be given to or served
upon the Maker or Payee shall be in writing and, if by telecopy, shall be deemed
to have been validly served, given or delivered when transmitted with a copy
immediately mailed by registered or certified mail, if by personal delivery,
shall be deemed to have been validly served, given or delivered upon actual
delivery and, if mailed, shall be deemed to have been validly served, given or
delivered three (3) business days after deposit in the United States mails, as
registered or certified mail, with proper postage prepaid and addressed to the
party to be notified, at the following addresses (or such other address(es) as a
party may designate for itself by like notice):

If to Maker:   Jayhawk Medical Acceptance Corporation
-----------    2001 Bryan Tower, Suite 600
               Dallas, Texas 75201
               Attention:  President

If to Payee:   Carl H. Westcott
-----------    100 Crescent Court, Suite 1620
               Dallas, Texas 75201

     15.  Successors and Assigns.  This Note shall be binding upon Maker and its
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successors and assigns (including, without limitation, a receiver, trustee or
debtor-in-possession of or for Maker) and shall inure to the benefit of Payee
and its successors and assigns.  Maker may not assign its rights hereunder
without the prior written consent of Payee, in its sole discretion.  Payee may
assign all or a part of its interest in this Note and its rights hereunder to
any party.

     16.  GOVERNING LAW.  THIS NOTE SHALL BE DEEMED A CONTRACT AND INSTRUMENT
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MADE UNDER THE LAWS OF THE STATE OF TEXAS AND ACCEPTED BY PAYEE IN SAID STATE,
THE LOCATION OF PAYEE'S PRINCIPAL PLACE OF BUSINESS, AND ANY AND ALL CLAIMS,
DEMANDS OR ACTIONS IN ANY WAY RELATING THERETO OR INVOLVING ANY DISPUTE BETWEEN
ANY OF THE PARTIES TO THIS NOTE, WHETHER ARISING IN CONTRACT OR TORT, AT LAW, IN
EQUITY OR STATUTORILY, SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH AND/OR
GOVERNED BY THE LAWS OF THE STATE OF TEXAS (EXCEPTING ITS
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CHOICE OF LAW RULES) AND THE LAWS OF THE UNITED STATES OF AMERICA. MAKER HEREBY
IRREVOCABLY SUBMITS ITSELF TO THE NON-EXCLUSIVE JURISDICTION OF THE STATE AND
FEDERAL COURTS OF THE STATE OF TEXAS AND AGREES AND CONSENTS THAT SERVICE OF
PROCESS MAY BE MADE UPON IT IN ANY LEGAL PROCEEDING RELATING TO THE TRANSACTION
DOCUMENTS, THE RELATIONSHIPS CREATED THEREBY OR THE DEBT BY ANY MEANS ALLOWED
UNDER TEXAS OR FEDERAL LAW. VENUE FOR ANY LEGAL PROCEEDING MAY BE DALLAS COUNTY,
TEXAS; PROVIDED, THAT PAYEE MAY CHOOSE ANY VENUE IN ANY STATE WHICH IT DEEMS
APPROPRIATE IN THE EXERCISE OF ITS SOLE DISCRETION.

     17.  WAIVER OF JURY TRIAL.  MAKER AND PAYEE HEREBY KNOWINGLY, VOLUNTARILY
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AND INTENTIONALLY WAIVE ANY RIGHT TO A TRIAL BY JURY IN RESPECT OF ANY
LITIGATION BASED HEREON, OR ARISING OUT OF, UNDER OR IN CONNECTION WITH, THIS
NOTE AND THE SECURITY AGREEMENT OR ANY COURSE OF CONDUCT, COURSE OF DEALING,
STATEMENTS (WHETHER VERBAL OR WRITTEN) OR ACTIONS OF PAYEE OR MAKER IN
CONNECTION HEREWITH, WHETHER NOW EXISTING OR HEREAFTER ARISING, AND WHETHER
SOUNDING IN CONTRACT, TORT OR OTHERWISE, MAKER AND PAYEE HEREBY CONSENT AND
AGREE THAT ANY SUCH CLAIM, DEMAND, ACTION, CAUSE OF ACTION, SUIT OR PROCEEDING
SHALL BE DECIDED BY A COURT TRIAL, WITHOUT A JURY, AND THAT ANY PARTY MAY FILE
AN ORIGINAL COUNTERPART OR COPY OF THIS NOTE WITH ANY COURT AS WRITTEN EVIDENCE
OF THE OTHER PARTIES' CONSENT TO SUCH.

     18.  Severability.  If any provisions of this Note or any payments pursuant
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to the terms hereof shall be invalid or unenforceable to any extent, the
remainder of this Note and any other payments hereunder shall not be affected
thereby and shall be enforceable to the greatest extent permitted by law.

     19.  Time of the Essence.  Time is of the essence with respect to all of
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Maker's obligations and agreements under this Note and the Security Agreement.

     IN WITNESS WHEREOF, the undersigned have executed and delivered this Note
as of the date and year first above written.

                         MAKER:

                         JAYHAWK MEDICAL ACCEPTANCE CORPORATION


                         By:
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                         Name:
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                         Title:
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