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                                                                  Exhibit 10.85


                              Restated Pursuant to
                          Amended and Restated "A" Note
                          Dated as of February 10, 1989

                                    "A" NOTE

            FOR VALUE RECEIVED, FIVE HUNDRED BOYLSTON WEST VENTURE ("Maker"), a
joint venture formed pursuant to the partnership laws of the Commonwealth of
Massachusetts, consisting of (1) BOYLSTON WEST 1986 ASSOCIATES LIMITED
PARTNERSHIP, a Texas limited partnership, (2) NEW ENGLAND MUTUAL LIFE INSURANCE
COMPANY, a mutual life insurance company, and (3) DIHC BOYLSTON ASSOCIATES, a
Georgia partnership, and having an address at 462 Boylston Street, Suite 3200,
Boston, Massachusetts 02116, promises to pay to DIHC FINANCE CORPORATION, its
successors is interest or assigns ("Payee"), at its office at 200 Galleria
Parkway, Suite 2000, Atlanta, Georgia 30339, or order, or at such other place as
may be designated in writing by the holder hereof, the principal sum of ONE
HUNDRED FIFTY THREE MILLION SIX HUNDRED FIFTY THOUSAND DOLLARS ($153,650,000),
or so much thereof as shall be advanced in accordance with the provisions of
that certain Building Loan Agreement (the "Building Loan Agreement") of even
date herewith between Maker and Payee, in lawful money of the United States of
America, on the thirty-fifth (35) anniversary of the date of this Note (the
"Maturity Date"), and to pay interest on the unpaid principal balance hereof
from the date hereof at the times and at the applicable rates of interest set
forth below.

            Until the Permanent Funding Date (as such term is defined in the
Building Loan Agreement), interest shall be computed on the outstanding
principal sum of One Hundred and Fifty Three Million Six Hundred Fifty Thousand
Dollars ($153,650,000), or so much thereof as

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shall have been advanced hereunder, at the rate of ten percent (10%) per annum.
Until the Permanent Funding Date, interest shall compound annually, provided,
however, that for any period in which the prime rate of interest as announced by
The Chase Manhattan Bank, N.A. shall be 10% or greater, interest on this Note
for such period shall compound monthly. Maker shall pay all accrued and unpaid
interest (i) or the tenth of each month, to the extent of 70% of Maker's Net
Cash Flow (as such term is hereinafter defined) for the immediately preceding
calendar month, and (ii) any interest not paid out of 70% of Maker's Net Cash
Flow as set forth in (i) above shall be paid annually on each anniversary of the
date of this Note occurring prior to the Permanent Funding Date and on the
Permanent Funding Date, as the case may be, from draws made under the Building
Loan Agreement for Interim Financing Costs (as such term is defined in the
Building Loan Agreement).

            After the Permanent Funding Date, interest shall be paid on the
tenth day of each month following the calendar month which includes the
Permanent Funding Date, in an amount in each case equal to all accrued and
unpaid interest on this Note. Such monthly dates for the payment of interest
after the Permanent Funding Date shall be referred to hereinafter as "Monthly
Payment Dates". The 28, 29, 30 or 31 day period, as the case may be, from the
Permanent Funding Date to the first Monthly Payment Date and from a Monthly
Payment Date to the next Monthly Payment Date shall be referred to as a "Monthly
Period". After the Permanent Funding Date, this Note shall bear interest as
follows (each of the interest rates set forth in the following four numbered
paragraphs being referred to hereinafter as the "Full Interest Rate" then in
effect under this Note after the Permanent Funding Date):

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            (1) at the rate of 8.00% per annum from and after the Permanent
Funding Date through and including the date immediately preceding the fifth
anniversary of the Permanent Funding Date;

            (2) at the rate of 8.50% per annum from and after the fifth
anniversary of the Permanent Funding Date through and including the date
immediately preceding the tenth anniversary of the Permanent Funding Date;

            (3) at the rate of 9.00% per annum from and after the tenth
anniversary of the Permanent Funding Date through and including the date
immediately preceding the fifteenth anniversary of the Permanent Funding Date;
and

            (4) at the rate of 10.00% per annum from and after the fifteenth
anniversary of the Permanent Funding Date through and including the Maturity
Date.

            On the Maturity Date, the outstanding principal balance of this
Note, together with all accrued and unpaid interest thereon shall be due and
payable.

            Commencing with the first month in which the Venture receives any
Gross Receipts (as such term is hereinafter defined) and for each calendar month
thereafter prior to the Permanent Funding Date, Maker shall cause a statement of
income and expense setting forth the elements and the calculation of
Pre-Debt-Service Net Cash Flow (as such term is hereinafter defined) for such
month to be prepared and furnished to Payee on or before the tenth day of the
month following the calendar month to which such statement applies. Each such
monthly statement shall be certified by an authorized representative of Maker.

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            Each payment received by Payee on account of this Note shall be
applied in the following order of priority: first, to the curing of any default
(including late charges) hereunder, under the Building Loan Agreement during the
term thereof or under that certain First Mortgage and Security Agreement (the
"Mortgage") of even date herewith, made by Maker to Payee to secure the payment
of this Note or under any other document executed by Maker pursuant to the terms
of this Note or the other agreements specified above (all such documents and
agreements referred to collectively hereinafter as the "Loan Documents");
second, to interest accruing at the applicable Full Interest Rate on the
outstanding principal balance hereof since the immediately preceding Monthly
Payment Date; and third, to the outstanding principal balance hereof.

            If any portion of the indebtedness evidenced hereby is not paid on
the date on which it is due, Maker shall pay to Payee, in addition to all
amounts otherwise due and payable under this Note, an amount equal to two
percent (2%) of such unpaid portion of the indebtedness evidenced hereby as a
late payment charge, and such amount shall be secured by the Mortgage.

            Upon (i) Payee notifying Maker of any monetary default hereunder, or
under that certain "B" Construction Note (the ""B" Note") of even date herewith
executed by Maker in favor of Payee, or under any of the Loan Documents, and the
continuance of such monetary default for a period of twenty (20) days after the
delivery of such written notice of default by Payee to Maker (the "Event of
Default") or (ii) Payee notifying Maker of any non-monetary default hereunder,
under the "B" Note or under any of the Loan Documents, and the continuance of
such default for a period of sixty (60) days after delivery of such written
notice of default by Payee, (or, if such non-monetary default is of the type
that cannot be cured in such period of time, then such

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additional period of time as is necessary to cure same, provided Maker promptly
commences to cure same and thereafter diligently and continually prosecutes to
completion the cure of same) (the "Event of Default"), Maker, at the option of
Payee, shall pay the principal and interest remaining due and unpaid hereunder
in accordance with the terms hereof and of the Mortgage, together with all costs
and expenses incurred in connection with the collection or attempted collection
hereof and the protection of the security hereof or thereof, including
reasonable attorneys' fees, whether or not suit is instituted. Interest shall
accrue on such past due amounts from the date of such Event of Default at the
"Involuntary Rate" (as hereinafter defined) compounded monthly until the date
such past due amounts together with such interest at the Involuntary Rate are
paid. The "Involuntary Rate" shall be:

      (A) for any advances, disbursements or moneys advanced by Payee in
      accordance with the terms of this Note, the Mortgage, the Building Loan
      Agreement or the other Loan Documents in furtherance of protecting the
      security hereof or thereof or for any monetary defaults set forth in
      clause (i) of this paragraph but prior to any acceleration by Payee of the
      debt evidenced by this Note, an annual rate equal to five percent (5%) in
      excess of the rate announced from time to time by The Chase Manhattan
      Bank, N.A. as its prime rate, on the past due amount or the amount so
      advanced, as the case may be, but in no event in excess of the then
      applicable maximum lawful rate.

      (B) in the event the principal amount of this Note and all interest due
      hereunder is accelerated by Payee in accordance with terms of this Note or
      the Mortgage, an annual rate computed from the date of such acceleration
      equal to the greater of (i) fifteen percent

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      (15%) or (ii) five percent (5%) in excess of the rate announced from time
      to time by The Chase Manhattan Bank, N.A. as its prime rate, on the
      principal and all interest and the amounts then due and payable, but in no
      event in excess of the then applicable maximum lawful rate.

            Maker (i) waives and renounces any and all exemption rights and the
benefit of all valuation and appraisal privileges as against the indebtedness
evidenced hereby or any renewal or extension thereof except as set forth in the
Mortgage, (ii) waives demand, protest, notice of nonpayment, and any and all
lack of diligence or delays in the collection or enforcement hereof, and (iii)
expressly consents to any extension of time, release of any of the security of
this Note, acceptance of other security therefor, or any other indulgence or
forbearance whatsoever by Payee, any one or all of which may be made without
notice to Maker or any other party.

            On or after the Permanent Funding Date Maker and Payee shall execute
and deliver an estoppel letter confirming the principal amount of this Note as
of such Date and, at the request of Payee, Maker shall execute and deliver a
note in replacement of this Note (upon surrender by Payee to Maker of this Note)
setting forth the then holder of this Note and the principal amount of this Note
then outstanding in the form and substance of this Note except that the terms
hereof relating to the period prior the Permanent Funding Date which are no
longer applicable shall be deleted. Any failure of Maker to execute such
replacement note complying with the above within thirty (30) days after delivery
by Payee of a request therefor, accompanied by such replacement note, shall be a
default under this Note but shall in no event affect the validity of this Note.

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            As used in this Note:

            (a) The term "Property" shall mean the property and improvements
encumbered by the Mortgage.

            (b) The term "Gross Receipts" shall mean the gross cash receipts
(computed in accordance with accepted cash basis accounting principles,
consistently applied) received by Maker, any of Maker's partners or agents on
behalf of Maker or any other person on behalf of Maker in cash or cash
equivalents (other than capital contributions made by Maker's partners, the
amounts borrowed hereunder or under the "B" Note or any other loan proceeds
received by Maker and proceeds of any sale, refinancing, condemnation, or
insurance recovery due to any casualty relating to the Property) from all
sources whatsoever as a direct or indirect result of the ownership or operation
of the Property or the operations of Maker including, without limitation, the
gross amounts received as rent, prepaid rent, additional rent, the proceeds of
rent insurance, fees, charges or otherwise (excluding security deposits unless
such security deposits are applied as payment of rent or forfeited upon default
under a lease), sundry income, concession income, interest on deposits
(including deposits in escrow pursuant to the Building Loan Agreement) provided
that such interest is not the property of tenants by lease or local law, the net
amount of any refund of impositions of tax applicable to any period through and
including the Maturity Date (to the extent that Maker is not required to remit
such refund to tenants) and the proceeds of any sale of personal property or
fixtures now or hereafter located on the Property.

            (c) The term "Operating Expenses" shall mean the operating expenses
actually paid by Maker, computed in accordance with accepted cash basis
accounting principles,

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consistently applied, for costs of: the maintenance, management, administration,
operation, repair and replacement of any portion of the Property except to the
extent financed by borrowings of Maker, amounts paid by Maker (including
reimbursements) to any property manager (but not construction manager),
administrator (but specifically excluding the "loan administration fee" payable
to DIHC Management Corporation for administering the loan advanced under the
Building Loan Agreement prior to the Permanent Funding Date), accountants,
attorneys or other agents for services rendered in connection with the operation
(as opposed to the initial construction) of the Property, and all other costs
specifically designated by and in accordance with the provisions hereof to be
Operating Expenses. Operating Expenses shall include the cost of or charges for
the following by way of illustration but not limitation: interest and other
periodic amortization, if any, on any indebtedness of Maker (excluding all
interest paid under this Note and the "B" Note" prior to the Permanent Funding
Date), whether or not secured by a lien on the Property, together with all other
costs incurred in connection with any such indebtedness or lien; advertising and
promotional costs; leasing commissions; real estate taxes and assessments; all
taxes upon the gross or net rental income of Maker derived from the Property;
water-and sewer charges; linkage payments (or alternatives thereto) to City or
the BRA under the Amended and Restated Sale and Construction Agreement dated as
of April 15, 1986; insurance premiums; licenses, permits and inspections (except
building permits and inspections relating to the initial construction of the
Improvements); heat, light and power; janitorial services; building staff;
garbage services; costs of providing air-conditioning; costs of supplies,
materials, equipment and tools for operating the Property; and the cost to Maker
of contesting by appropriate proceedings

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the applicability to the Property, or the validity, of any statute, ordinance,
rule or regulation affecting the Property which might increase Operating
Expenses, provided, however, that Operating Expenses shall not include
depreciation, amortization of any previously capitalized expenditure or any
other expense not involving a cash expenditure by Maker.

            (d) The term "Net Cash Flow" for any period shall mean an amount
equal to Gross Receipts of such period less the sum of Operating Expenses for
such period and a reasonable reserve for contingencies and for general working
capital requirements of Maker.

            (e) The term "Pre-Debt-Service Net Cash Flow" for any period shall
mean an amount equal to the Net Cash Flow for such period computed without
regard to any deduction, as an Operating Expense, for interest paid on this
Note.

            This Note may not be prepaid in whole or in part prior to the
Permanent Funding Date except to the extent that 70% of the Pre-Debt Service Net
Cash Flow of Maker exceeds interest (and any other charges) payable hereunder.
After the Permanent Funding Date, this Note may not be prepaid in whole or in
part prior to the eighth (8th) anniversary of the Permanent Funding Date, except
at the times and to the extent set forth in that certain Escrow Agreement to be
executed by Maker, Payee and DIHC Boylston Associates pursuant to the Building
Loan Agreement (at which time such amount shall be due and payable hereunder
without premium or penalty), and may be prepaid in whole (but not in part) at
any time following the eighth (8th) anniversary of the Permanent Funding Date
upon thirty (30) days prior written notice to Payee and upon payment of the
following prepayment premium (based on the principal amounts so

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prepaid) computed with respect to the year after the Permanent Funding Date
during which such prepayment is made:

               Year after Permanent
                   Funding Date                 Premium
                   ------------                 -------
                        9th                     6%
                       10th                     5%
                       11th                     4%
                       12th                     3%
                       13th - 20th              2%

At any time following the twentieth (20th) anniversary of the Permanent Funding
Date, this Note may be prepaid in whole or in part without premium or penalty
upon thirty (30) days' prior written notice to Payee. Upon any Event of Default
hereunder, and following any acceleration by Payee (except for an acceleration
resulting from an event described in Paragraphs 4(a) or 4(b) of the Mortgage)
prior to the eighth anniversary of the Permanent Funding Date of the obligation
to pay the entire outstanding principal balance hereof and all accrued and
unpaid interest hereon, a tender (the "Tender") of payment of the principal and
interest remaining due and unpaid hereunder, made by Maker or anyone on behalf
of Maker at any time at or prior to foreclosure or mortgagee's sale, shall
constitute an evasion of the payment terms hereof and shall be deemed to be a
voluntary prepayment and such payment, to the extent permitted by law, shall
include a prepayment premium in an amount equal to 12% of the principal amount
so Tendered (or, for the period beginning from the eighth anniversary of the
Permanent Funding Date until the twentieth anniversary of such date, a
prepayment premium in accordance with the schedule set forth above).

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Notwithstanding anything herein to the contrary, this Note shall be prepaid, in
whole or in part without premium or penalty, from any recoveries under title
insurance policies covering the Property or from any undisbursed insurance
proceeds and condemnation awards required by the terms of the Mortgage to be
applied on the indebtedness evidenced by this Note.

            The parties hereto have intended in good faith to comply with all
applicable usury laws. Notwithstanding anything to the contrary contained in
this Note or any of the other Loan Documents, Maker shall not be obligated to
pay interest at a rate which would subject Payee to either criminal or civil
liability. If, by the terms of this Note or any of the other Loan Documents,
Maker is ever obligated to pay interest on the principal balance hereof in an
amount or at a rate in excess of the applicable lawful maximum, then the
interest due to Payee shall be immediately and automatically reduced to such
maximum, the interest payable shall be computed at such maximum rate, and all
prior interest payments in excess of such lawful maximum shall be immediately
and automatically applied, and shall be deemed to have been treated as having
been applied at the time of receipt, in reduction of the principal balance due
under this Note.

            No delays on the part of Payee in exercising any right hereunder or
under the Building Loan Agreement, the "B" Note, the Mortgage or any of the
other Loan Documents shall operate as a waiver thereof or preclude the exercise
thereof at any time during the continuance of any default of which Payee has
given written notice to Maker or during the continuance of a subsequent default
of which Payee has given written notice to Maker.

            Notwithstanding any other provision of this Note or any of the Loan
Documents, neither the obligation of Maker to pay the debt evidenced by this
Note and the Mortgage nor the

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obligation of Maker to perform any covenant or agreement contained in this Note,
the Mortgage, or any of the other Loan Documents shall be enforced by any action
or proceeding wherein or whereby damages or any money judgment shall be sought
against Maker or any of its partners or officers, directors or partners of such
partners, except a foreclosure or other action against the Property encumbered
by the Mortgage, and any judgment in any such foreclosure or other action shall
be enforceable against Maker only to the extent of its interest in such Property
and the income therefrom and no deficiency or other personal judgment shall be
rendered or entered against Maker or any of its partners or officers, directors
or partners of such partner in such foreclosure or other action; provided,
however, that Maker (and Maker's partners) shall be personally liable, following
the receipt of a notice of default hereunder or under any of the Loan Documents,
to apply, prior to the Permanent Funding Date, 70% of the Pre-Debt-Service Net
Cash Flow of the Venture, and, after the Permanent Funding Date, all Pre-Debt
Service Net Cash Flow of the Venture received after the notice of default to
cure such default, before applying such receipts in any other manner. Nothing in
this paragraph shall, however, (1) be deemed to affect the priority of the lien
of the Mortgage, (2) impair the right of Payee to accelerate the maturity of
this Note (or to avail itself of its other rights and remedies against the
Property and Maker's interest therein) upon an Event of Default under this Note,
the Mortgage or any other Loan Documents, or (3) relieve Maker of any of the
covenants or obligations set forth in this Note, the Mortgage or the other Loan
Documents subject, however, to the limitations on personal liability set forth
above.

            This Note may not be modified or terminated orally.

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            This Note has been delivered in Boston, Massachusetts and shall be
construed and enforced in accordance with the laws of the Commonwealth of
Massachusetts.

            The property encumbered by the Mortgage is located in the City of
Boston, Massachusetts.

            Any and all notices, approvals, requests and other communications to
be given hereunder shall be served and delivered in the manner set forth in the
Mortgage.

            IN WITNESS WHEREOF, Maker has executed this Note under seal as of
the 29th day of May, 1986.

                                       FIVE HUNDRED BOYLSTON WEST
                                       VENTURE, a joint venture

                                 By:   BOYLSTON WEST 1986 ASSOCIATES
                                       LIMITED PARTNERSHIP, a joint venturer

WITNESS:                               By:   Gerald D. Hines Interests, Ltd.,
                                             doing business in Massachusetts as
                                             Gerald D. Hines Interests, Limited
                                             Partnership, its general partner

/s/ (signature illegible)              By:   /s/ Gerald D. Hines
-------------------------                    -------------------
                                             Gerald D. Hines,
                                             General Partner ESO

                                 By:   NEW ENGLAND MUTUAL LIFE
                                       INSURANCE COMPANY, a joint venturer

                                 By:   COPLEY REAL ESTATE
WITNESS:                               ADVISORS, INC., its agent and duly
                                       authorized asset manager

/s/ (signature illegible)        By:   /s/ William J. Salisbury
-------------------------              ------------------------
                                         William J. Salisbury,
                                         Principal

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                                    By:   DIHC BOYLSTON ASSOCIATES, a joint
                                          venturer

WITNESS:                                  By:   DIHC BOYLSTON CORP., a
                                                partner

/s/ (signature illegible)                       By:   /s/ Herman A. Vonhof
-------------------------                             --------------------
                                                      Herman A. Vonhof
                                                      President

WITNESS:                                  By:   DIHC ST. JAMES CORP., a partner

/s/ (signature illegible)                       By:   /s/ Herman A. Vonhof
-------------------------                             --------------------
                                                      Herman A. Vonhof,
                                                      President

<PAGE>

                           ASSIGNMENT OF "A" NOTE AND

                      FIRST MORTGAGE AND SECURITY AGREEMENT

            FOR VALUE RECEIVED, DIHC FINANCE CORPORATION (formerly known as
Dutch Institutional Finance Corporation, Inc.), a Georgia corporation having an
office at Suite 2000, 200 Galleria Parkway, Atlanta, Georgia ("Assignor"), has
this day granted, bargained, sold, assigned, transferred and set over unto
STICHTING PENSIOENFONDS VOOR DE GEZONDHEID, GEESTELIJKE EN MAATSCHAPPELIJKE
BELANGEN, a foundation formed according to the laws of The Netherlands, having
an office at Kroostweg Number 149, Zeist, The Netherlands ("Assignee"), all of
Assignor's right, title and interest in and to that certain First Mortgage and
Security Agreement and to that certain "A" Note in the original principal amount
of up to ONE HUNDRED FIFTY-THREE MILLION SIX HUNDRED FIFTY THOUSAND DOLLARS
($153,650,000) dated as of May 29, 1986 granted by FIVE HUNDRED BOYLSTON WEST
VENTURE, a joint venture formed pursuant to the partnership laws of the
Commonwealth of Massachusetts, consisting of (1) BOYLSTON WEST 1986 ASSOCIATES
LIMITED PARTNERSHIP, a Texas Limited partnership, (2) NEW ENGLAND MUTUAL LIFE
INSURANCE COMPANY, a mutual life insurance company, and (3) DIHC BOYLSTON
ASSOCIATES, a Georgia partnership, and having an address at 500 Boylston Street,
Suite 1800, Boston, Massachusetts 02116, to Assignor, and recorded in the
Suffolk County Registry of Deeds Office, Boston, Massachusetts, in Book 12524 at
Page 319, and filed with the Suffolk Registry District of the Land Court as
Document Number 405540, together with moneys due and to become due thereon.

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            TO HAVE AND TO HOLD the same unto Assignee, its successors and
assigns from and after the date hereof.

            AND Assignor covenants that as of this date there was due and owing
on the said note principal and interest under said note in the aggregate amount
of $118,230,463.78.

            IN WITNESS WHEREOF, Assignor has caused its corporate seal to be
hereto affixed and these presents to be signed in its name and behalf by Charles
W. Strawser, Jr., its Senior Vice-President, as of the 10th day of February,
1989.

Signed and Sealed in                      DIHC FINANCE CORPORATION
 Presence of


/s/ Susan M. Harris                       By: /s/ Charles W. Strawser, Jr.
------------------------------               ----------------------------------
                                              Name:  Charles W. Strawser, Jr.
/s/ Melissa W. Carter                         Title: Senior Vice President
------------------------------


                                        2

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                                 ACKNOWLEDGMENT

STATE OF GEORGIA  )
                  : ss.
COUNTY OF COBB    )

            On this 17th day of February, 1989, before me appeared CHARLES W.
STRAWSER, JR., Senior Vice-President of DIHC Finance Corporation, who made oath
that the foregoing statement is true.

                                                /s/ Susan M. Talbott
                                                --------------------------------
                                                Notary Public


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