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                                                                   EXHIBIT 10.35

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                            MEDICAL PROPERTIES TRUST

March 3, 2005

Jerome S. Tannenbaum, M.D., Ph.D., FACP
Chairman, President and CEO
Diversified Specialty Institutes, Inc.
511 Union Street, Suite 1800
Nashville, Tennessee 37219

         RE:      COMMITMENT LETTER FOR ACQUISITION AND DEVELOPMENT LINE

Dear Dr. Tannenbaum:

MPT Operating Partnership, L.P., or its designated affiliates (collectively,
"MPT"), are pleased to extend a commitment to Diversified Specialty Institutes,
Inc., or its affiliates (collectively, "DSI" or "LESSEE") respecting an
acquisition and development facility (the "Line") to be used to finance the
acquisition of certain existing healthcare facilities (the "Acquisition
Facilities") and the development of certain other healthcare facilities (the
"Development Facilities"). The real estate and improvements relating to the
Acquisition Facilities and the Development Facilities shall hereinafter be
referred to, collectively, as the Real Estate, and the operating permits,
licenses, and other non-Real Estate assets relating to the Acquisition
Facilities and the Development Facilities shall hereinafter be referred to
collectively as the Operations. Contemporaneously with MPT's acquisition of the
Real Estate respecting any Acquisition Facility or Development Facility, such
Real Estate shall be leased by MPT to LESSEE on the terms herein provided.

The closing of the Line itself (the "Line Closing") is subject to: (i) MPT being
satisfied, in its reasonable discretion, with the results of its due diligence
investigation of LESSEE, (ii) the execution of definitive agreements relating to
the Line, which are consistent with the terms hereof; (iii) the obtaining of any
necessary consents and approvals of governmental entities and third parties; and
(iv) such other conditions to such closing as are described herein or as are
customary in similar transactions. The closing of any acquisition of Real Estate
with respect to any particular Acquisition Facility or Development Facility
(each a "Closing") shall be subject to: (i) MPT being satisfied, in its
reasonable discretion, with the results of its due diligence investigation of
LESSEE and such Acquisition Facility or Development Facility, as the case may
be, including the Real Estate and the Operations with respect thereto; (ii) the
execution of definitive agreements respecting the acquisition and/or development
of the Real Estate with respect to such Acquisition Facility or Development
Facility, as well as the lease and other definitive agreements relating to the
leaseback of such Real Estate; (iii) MPT's receipt of a current title insurance
policy and survey respecting such Real Estate, provided at LESSEE'S expense,
which are in form and substance satisfactory to MPT; (iv) MPT's receipt of a
recent phase one environmental study for such Real Estate, provided at LESSEE'S
expense,

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which is in form and substance satisfactory to MPT; (v) MPT's receipt of a
recent engineering (soil condition) report respecting the condition of such Real
Estate, provided at LESSEE'S expense, which is in form and substance
satisfactory to MPT; (vi) the obtaining of any consents and approvals of
governmental entities or third parties; (vii) the approval of such acquisition
or development and leaseback by the Board of Directors of Medical Properties
Trust, Inc.; and (viii) such other conditions to such closing as are described
herein or as are customary in similar transactions.

                                    ARTICLE I

                                   BASIC TERMS

SECTION 1.1 BASIC TRANSACTION: It is the parties' intent for MPT to make
available a total Line of Fifty Million Dollars ($50,000,000). The Line shall be
utilized to acquire Real Estate with respect to Acquisition Facilities and to
acquire and develop Real Estate with respect to Development Facilities. The Line
shall remain outstanding until the first anniversary of the date of acceptance
of this Commitment Letter (the "Outside Date"), it being understood and agreed
that the Line shall be available to finance any Acquisition Facility or
Development Facility that is subject to definitive agreements as of the Outside
Date, notwithstanding that the closing or completion of such Acquisition
Facility or Development Facility may not have occurred as of the Outside Date.

         SECTION 1.1.1 CONVEYANCE OF REAL ESTATE: The conveyance of each parcel
         of Real Estate shall be by general warranty deed conveying good and
         marketable title, free and clear of any liens and encumbrances, except
         for liens and encumbrances reasonably acceptable to MPT (the "Permitted
         Exceptions").

         SECTION 1.1.2 DEVELOPMENT: MPT shall be responsible for funding the
         Total Development Costs (as herein defined) for any Development
         Facility. Total Development Costs shall include all costs and expenses
         associated with the purchase, development, and lease of the Real Estate
         relating to such Development Facility, including, but not limited to,
         the purchase price paid for the Real Estate, legal, appraisal, title,
         survey, environmental, engineering, and other fees paid to advisors and
         or brokers, expenses of site visits, and all other development costs.
         During the period of development of any Development Facility, funds
         shall be advanced pursuant to requests made by LESSEE in accordance
         with the terms and conditions of a development agreement entered into
         by MPT with the developer of such Development Facility (the
         "Development Agreement"). Any such Development Agreement shall provide
         that, prior to any advance of funds, the developer shall be required to
         provide MPT with the following:

                  (a)      TITLE INSURANCE: Satisfactory evidence in the form of
         an endorsement to the original title insurance policy that no
         intervening liens have been placed on the Real Estate relating such to
         Development Facility since the date of the previous advance;

                  (b)      ARCHITECT'S CERTIFICATE: A certificate executed by
         the architect of record (the "Architect's Certificate") that indicates
         that all construction work completed on such Real Estate conforms with
         the requirements of the plans, specifications, and any change orders
         previously approved by MPT;


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                  (c)      CONTRACTOR'S CERTIFICATE; LIEN WAIVER: A certificate
         executed by the general contractor or construction manager that all
         work that is the subject of a request for reimbursement has been
         completed and a lien waiver that all bills have been paid; and

                  (d)      CONSTRUCTION REPORT: Approval by MPT of the
         Architect's Certificate.

LESSEE shall designate the general contractor, developer, architect,
construction company, engineer, and other parties which will participate in the
development of the Development Facility, however, MPT shall control the
preparation and negotiation of the definitive agreements with such parties. MPT
will give LESSEE an opportunity to review such definitive agreements prior to
their execution.

SECTION 1.3 LEASE: On the date of Closing with respect to any Acquisition
Facility or Development Facility (each a "Closing Date"), the parties shall
execute a lease agreement for the Real Estate for such Acquisition Facility or
Development Facility in a form mutually satisfactory to the parties
(collectively the "Leases" and individually a "Lease") generally in accordance
with the terms set forth herein. The term of each Lease shall be for a period of
fifteen (15) years commencing on the Closing Date and (so long as there is no
default under the Leases) each Lease shall provide for three (3) options
exercisable by LESSEE, in its sole discretion, to extend for five (5) years so
long as the options are exercised at least six (6) months prior to the
expiration of the Lease. Each Lease shall provide that at the expiration of the
initial term of the Lease and at the expiration of each extended term
thereafter, so long as there is no default under the Leases, LESSEE shall have
the option to purchase the Real Estate at a purchase price equal to the greater
of (i) the appraised fair market value of such Real Estate (which appraisal
shall assume that the Lease remains in effect for a term of fifteen (15) years),
or (ii) the amount of (A) the purchase price paid for the Real Estate, including
costs of third party reports, legal fees, and all other acquisition costs (the
"Purchase Price"), in the case of Acquisition Facilities, or, (B) Total
Development Costs, in the case of Development Facilities, in each case increased
by an amount equal to the greater of (1) two and one-half percent (2.5%) per
year from the Closing, or (2) the rate of increase in the Consumer Price Index
on each Adjustment Date. As used herein, the term "Consumer Price Index" means
the Consumer Price Index, all urban consumers, all items, U.S. City Average,
published by the United States Department of Labor, Bureau of Labor Statistics,
in which 1982-1984 equals one hundred (100). As used herein, the term
"Adjustment Date" means January 1 of each year commencing on the first January
1st following commencement of the Lease, with respect to Acquisition Facilities,
or on the first January 1st following the completion date, in the case of
Development Facilities. Each Lease shall further provide that LESSEE may
exercise the purchase option described above upon at least sixty (60) days'
written notice and LESSEE shall be required to close within ninety (90) days
following delivery of such notice.

SECTION 1.4 RENTS: Each Lease of Real Estate shall provide for the following
rents:

         SECTION 1.4.1 CONSTRUCTION PERIOD RENT FOR DEVELOPMENT FACILITIES:
         During the construction period (the "Construction Period"), if
         applicable, LESSEE shall pay MPT, in consecutive monthly installments,
         a per annum amount equal to 10.75% multiplied by the total amount of
         Total Development Costs disbursed under the applicable Development
         Agreement (the "Construction Period Rent"). The Construction Period
         Rent shall commence on the first day of

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         the month following the month in which the first funds are disbursed
         under the applicable Development Agreement, and shall continue to be
         paid by LESSEE to MPT on the first (1st) day of each month.

         SECTION 1.4.2 BASE RENT: Following the Construction Period with respect
         to any Development Facility and from the date of commencement of the
         Lease with respect to any Acquisition Facility, the aggregate annual
         base rent ("Base Rent") for the Real Estate shall be an initial annual
         rate of 10.75% multiplied by the Total Development Costs or Purchase
         Price, as the case may be. The Base Rent shall be payable in twelve
         (12) equal monthly installments.

         SECTION 1.4.3 RENT INCREASE: Commencing on the first January 1st
         following commencement of the Lease, with respect to Acquisition
         Facilities, and the first January 1st following the completion date,
         with respect to Development Facilities, and on each January 1st
         thereafter (each such date an "Adjustment Date") the Base Rent shall be
         increased by an amount equal to the greater of (A) two and one-half
         percent (2.50%) of the prior year's Base Rent, or (B) the percentage by
         which the Consumer Price Index on the Adjustment Date shall have
         increased over the Consumer Price Index figure in effect on the then
         just previous Adjustment Date. If the previous year's Base Rent is for
         a partial year, it shall be annualized.

         SECTION 1.4.4 CAPITAL IMPROVEMENT RESERVE: Commencing on the date that
         construction has been completed with respect to Development Facilities,
         or on the date of commencement of the Lease with respect to Acquisition
         Facilities, and on each January 1 thereafter, LESSEE will be required
         to make annual deposits into a Capital Improvement Reserve (the
         "Capital Improvement Reserve"), at a financial institution of MPT's
         choosing, in the amount of $2,500 per bed, which amount shall increase
         each January 1st by 2.50%. Such reserve shall be under the joint
         control of MPT and LESSEE and shall be used for the repair and
         replacement of capital items on the Real Estate and as expressly
         provided in the Lease.

 SECTION 1.5 ABSOLUTE TRIPLE NET LEASE: Each parcel of Real Estate will be
 leased to LESSEE on an absolute triple-net or fully-netted basis. The LESSEE
 will be responsible for all costs of the Real Estate, including, but not
 limited to, taxes, insurance, and maintenance.

 SECTION 1.6 SECURITY: As security for the performance of LESSEE'S obligations
 under the Leases, MPT shall be granted a security interest in LESSEE'S personal
 property (excluding accounts receivable and the proceeds thereof) (subject to
 any contract lien and security interest of LESSEE'S primary lender (the
 "Primary Lender") providing financing for LESSEE to purchase the personal
 property) and shall receive from LESSEE an assignment of any rents and leases.
 The Leases shall be cross-defaulted and shall also be cross-defaulted with any
 other lease between LESSEE, or its affiliates, and MPT, or its affiliates. If
 LESSEE obtains financing from a Primary Lender, LESSEE will use commercially
 reasonable efforts to obtain from its Primary Lender a consent to a secondary
 lien on the personal property in favor of MPT, in form and content reasonably
 acceptable to Primary Lender and LESSOR. LESSEE shall not place any liens, or
 allow any other liens to be placed, on the personal property.

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 SECTION 1.7 COMMITMENT FEE: LESSEE shall pay to MPT a commitment fee (the
"Commitment Fee") equal to One Percent (1%) of the Line, of which amount One
Hundred Thousand Dollars ($100,000) shall be due and payable upon the execution
of this Commitment Letter. The remainder of the fee shall be due and payable at
the closing of future projects, with such fee on each project being equal to
One Percent (1%) of that project's purchase price. Credit shall be given on
future payments of Commitment Fees for the One Hundred Thousand Dollars
($100,000) paid upon the execution of this letter.

SECTION 1.8 LINE CLOSING DATE: MPT and DSI agree that time is of the essence and
the parties will prepare, negotiate, and execute the documentation relating to
the Line, consistent with the terms hereof, and will use their good faith
reasonable efforts to close the Line (the "Line Closing") by February 28, 2005.
The definitive documents shall provide that the Transaction must close (the
"Line Closing Date") by March 31, 2005, unless either party requests a thirty
(30) day extension, such request not to be unreasonably withheld by the other
party.

SECTION 1.9 FINANCIAL INFORMATION AND COVENANTS: MPT must receive, prior to the
Line Closing, audited financial statements of DSI for the three most recent
fiscal years and any current year-to-date interim financial statements of DSI.
In addition, with respect to the Closing of any Acquisition Facility or
Development Facility. MPT also shall receive five years pro forma for such
Acquisition Facility or Development Facility prior to Closing. The Leases will
require that MPT receive on a continuing basis during the term of the Leases,
within the times as hereinafter set forth, the following:

                  (a)      Within ninety (90) days after the end of each year,
         audited financial statements of DSI and LESSEE'S Operations by a
         nationally recognized accounting firm or an independent certified
         public accounting firm reasonably acceptable to MPT, which statements
         shall include a balance sheet and a statement of income and expenses
         for the year then ended; plus

                  (i)      Within forty-five (45) days after the end of each
                           quarter, current financial statements of DSI and
                           LESSEE'S Operations certified to be true and correct;
                           and

                  (ii)     Within thirty (30) days after the end of each month,
                           current operating statements of LESSEE'S Operations
                           certified to be true and correct.

                  (b)      Upon request, a certificate in form acceptable to
         MPT, that no event of default as defined in the Leases (a "Default")
         then exists and no event has occurred (that has not been cured) and no
         condition currently exists that would, but for the giving of any
         required notice or expiration of any applicable cure period, constitute
         a Default.

                  (c)      Within ten (10) days of receipt, any and all notices
         (regardless of form) from any and all licensing and/or certifying
         agencies that any license or certification, including, without
         limitation, the Medicare or Medicaid certification of the Acquisition
         Facility or Development Facility, is being downgraded, revoked, or
         suspended, or that action is pending or being considered to downgrade,
         revoke, or suspend such Acquisition Facility's or Development
         Facility's license or certification.

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                  (d)      MPT reserves the right to require such other
         financial information from DSI at such other times as it shall deem
         reasonably necessary. All financial statements must be in such form and
         detail as MPT shall from time to time, but not unreasonably, request.

SECTION 1.10 FINANCIAL COVENANTS: The parties shall mutually develop and agree
upon certain financial covenants to be included in each Lease, and the failure
to achieve such covenants shall constitute an event of default thereunder.
LESSEE'S Operations shall in the aggregate maintain EBITDAR coverage of at least
two hundred percent (200%) of the Base Rent.

SECTION 1.11 SUBLEASE, MANAGEMENT AND ASSIGNMENT: LESSEE shall not sublease or
assign (which will be broadly defined) any Lease or engage a management company
without MPT's prior consent, which shall not be unreasonably withheld or
delayed. Any such assignment shall not release the LESSEE. Any sublease shall be
subordinate to the applicable Lease and may be terminated or left in place by
MPT in the event of a termination of such Lease.

[SECTION 1.12 CASH INJECTION: On any Closing Date, the LESSEE either shall have
tangible net worth of no less than Five Million Dollars ($5,000,000) in cash
equity or shall have access to a working capital line of credit of no less than
Five Million Dollars ($5,000,000) that is personally guaranteed by Jerome S.
Tannebaum, M.D., and such other persons as may be approved by MPT, which
approval shall not be unreasonably withheld.

SECTION 1.13 LETTER OF CREDIT: Simultaneously with the execution and delivery of
any Lease by LESSEE, LESSEE shall obtain and deliver to MPT an unconditional and
irrevocable letter of credit from a bank acceptable to MPT, naming MPT
beneficiary thereunder, in an amount equal to one (1) year's Base Rent under
such Lease.

SECTION 1.14 SYNDICATION: If requested, MPT will permit up to twenty percent
(20%) of the Real Estate relating to a particular Acquisition Facility or
Development Facility to be owned by local or area physicians. MPT and DSI will
work together to decide which physicians receive an opportunity to invest in
such Real Estate. The physicians will invest on an equal basis with MPT.

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                                   ARTICLE II

                                 THE FACILITIES

SECTION 2.1 ACCESS TO INFORMATION: With respect to the Line Closing, from the
date hereof, DSI will provide MPT and its representatives (including architects,
engineers, surveyors, attorneys, accountants, investment bankers, and other
representatives) with reasonable and available access to DSI and the officers,
agents, and employees of DSI. In addition, with respect to any particular
Acquisition Facility or Development Facility, DSI shall provide the same access
as provided in connection with the Line Closing and, in each case, DSI shall
furnish or cause to furnish MPT's representatives with all financial, operating,
and other data or information relating to DSI and, if applicable, the Real
Estate and the Operations, as may be reasonably requested in connection with
MPT's due diligence review.

SECTION 2.2 APPROVAL OF THE FACILITIES: MPT shall have the right to review and
approve all aspects an Acquisition Facility or Development Facility, including
the final configuration of the Real Estate with respect to a particular
Acquisition Facility or Development Facility, the location of any improvements
on such Real Estate, the location of all roads and interchanges in relation to
such Real Estate, the location of all property lines, utilities, easements,
rights of way, common areas, and amenities affecting the Acquisition Facility or
Development Facility, and the soil and subsurface engineering studies,
investigations, and reports that support and justify the location of the
Acquisition Facility or Development Facility. Such Real Estate shall include
such easements, rights-of-way and other privileges as are necessary to conduct
the business of the Acquisition Facility or the Development Facility, as the
case may be.

SECTION 2.3 INSPECTION OF FACILITIES:

                  (a)      With respect to any Development Facility, Total
         Development Costs shall include a fee to MPT in the amount of
         Seventy-Five Thousand Dollars ($75,000) per Development Facility to
         cover the cost of MPT's inspections of each such Development Facility
         during the construction stage.

                  (b)      LESSEE shall pay MPT Seven Thousand Five Hundred
         Dollars ($7,500) (increasing at the rate of two and one-half percent
         (2.5%) per year starting on the first January 1st following
         commencement of the Lease, in the case of an Acquisition Facility, or
         the completion date, in the case of a Development Facility) for each
         Acquisition Facility or Development Facility to cover the cost of
         physical inspections. DSI shall maintain all Acquisition Facilities and
         Development Facilities in a first class manner and shall be required to
         respond to any deficiencies reported in these annual reports.
         Furthermore, LESSEE shall report to MPT on any and all major
         improvement or repairs in excess of Ten Thousand Dollars ($10,000)
         LESSEE makes to any such Acquisition Facility or Development Facility.

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SECTION 2.4 MPT'S RIGHT TO INSPECT FACILITIES: MPT and its representatives shall
have the right to make periodic inspections of each Acquisition Facility or
Development Facility from time to time upon reasonable prior notice to LESSEE.
MPT shall use every effort to not disrupt the patient care being provided at the
Acquisition Facility or Development Facility. MPT recognizes the importance of
patient privacy.

SECTION 2.5 EXPANSIONS AND RENOVATIONS: MPT shall have a right of first
opportunity to fund any expansions or material renovations requested by LESSEE.
The Lease term for the expansions or renovations shall be identical to the term
of the underlying Lease.

                                   ARTICLE III

                              CONDITIONS PRECEDENT

SECTION 3.1 LINE CLOSING: Prior to the Line Closing and in addition to any
conditions addressed elsewhere in the Commitment Letter, MPT shall have been
furnished with the following, each of which must be, in form and substance,
reasonably satisfactory to MPT and MPT's counsel:

         SECTION 3.1.1 UCC SEARCHES: UCC searches to ensure that no liens other
         than Permitted Exceptions have been filed against DS1.

         SECTION 3.1.2 ATTORNEY'S OPINION: An opinion of counsel for the LESSEE
         addressed to MPT covering such matters as MPT and MPT's counsel may
         reasonably require.

         SECTION 3.1.3 ORGANIZATIONAL DOCUMENTS: Certified copies of the
         organizational documents of the LESSEE together with such resolutions,
         consents, and similar documents evidencing the authorization of the
         transactions contemplated as MPT and its counsel may require.

         SECTION 3.1.4 OTHER: Such other documents, certificates, and the like,
         as may be customary in comparable transactions or as MPT or MPT's legal
         counsel may otherwise reasonably require.

SECTION 3.2 OTHER CLOSINGS: Prior to any Closing of an Acquisition Facility or
Development Facility and in addition to any conditions addressed elsewhere in
the Commitment Letter, MPT shall have been furnished with the following, each of
which must be, in form and substance, reasonably satisfactory to MPT and MPT's
counsel:

         SECTION 3.2.1 CONTRACTS, CONSENTS AND LIEN WAIVERS: Fully executed
         counterparts of any previously executed contracts with architects,
         engineers, contractors, and material subcontractors and lien waivers
         and subordinations pursuant to which such parties release all liens for
         work performed by them prior to the Closing.

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         SECTION 3.2.2 GOVERNMENTAL APPROVALS AND LICENSES: Copies of all
         permits, licenses, and other approvals of governmental authorities
         required for the operation of such Acquisition Facility or Development
         Facility for its intended use and written evidence satisfactory to MPT
         that the operation and use of such Acquisition Facility or Development
         Facility is in accordance with all applicable governmental
         requirements.

         SECTION 3.2.3 TITLE INSURANCE: At LESSEE'S expense, a title insurance
         policy conforming to the requirements set forth in Exhibit B hereto
         issued by a title insurance company satisfactory to MPT, insuring the
         particular parcel of Real Estate. The title policy shall contain no
         exceptions other than Permitted Exceptions and shall contain a general
         comprehensive endorsement (ALTA 9), an ALTA 3.0 zoning endorsement and
         such other endorsements as MPT may require. LESSEE will provide any
         customary affidavits and certifications required by the title company.

         SECTION 3.2.4 INSURANCE: LESSEE must provide evidence to MPT that the
         LESSEE is maintaining insurance on such Acquisition Facility or
         Development Facility as set forth in Exhibit B, and that MPT and any
         lender of MPT are named as additional insureds and, where applicable,
         loss payees.

         SECTION 3.2.5 SURVEY: At LESSEE'S expense, a current survey of the
         particular parcel of Real Estate prepared and certified by a duly
         registered land surveyor licensed, and in good standing in the state
         where such Real Estate is located, and acceptable to MPT. The survey
         shall comply with ALTA requirements, shall show all improvements and
         encroachments located on such Real Estate, and all recorded or visible
         easements, rights-of-way, and similar encumbrances affecting the title
         to such Real Estate, shall contain a certification in the form shown on
         Exhibit C and shall state whether or not such Real Estate lies within a
         designated flood hazard zone.

         SECTION 3.2.6 UCC SEARCHES: UCC searches to ensure that no liens other
         than Permitted Exceptions have been filed against such Acquisition
         Facility or Development Facility or DSI.

         SECTION 3.2.7 ZONING: Evidence that the particular parcel of Real
         Estate, and the use and occupancy thereof, will comply with all
         applicable governmental requirements related to planning, zoning, and
         land use.

         SECTION 3.2.8 PLANS: To the extent LESSEE has them, LESSEE will provide
         MPT with one complete set of final plans and specifications for any
         Development Facility.

         SECTION 3.2.9 ATTORNEY'S OPINION: An opinion of counsel for the LESSEE
         addressed to MPT covering such matters as MPT and MPT's counsel may
         reasonably require.

         SECTION 3.2.10 ENVIRONMENTAL MATTERS: An environmental indemnity
         agreement, mutually acceptable to LESSEE and MPT, executed by LESSEE in
         favor of MPT. Pursuant to that agreement, the LESSEE shall make various
         environmental representations and warranties to MPT and shall indemnify
         and hold harmless MPT from environmental claims and liabilities.

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         including, without limitation, claims and liabilities arising from any
         hazardous or toxic materials present on the particular parcel of Real
         Estate and from any violations of environmental laws and regulations.

         SECTION 3.2.11 ORGANIZATIONAL DOCUMENTS: Certified copies of the
         organizational documents of the LESSEE, together with such resolutions,
         consents, and similar documents evidencing authorization of the
         acquisitions and developments contemplated by this commitment, as MPT
         and its counsel may require.

         SECTION 3.2.12 APPRAISAL: MPT acknowledges, that, in order to
         facilitate a timely Closing, LESSEE, at its expense, shall order an
         appraisal on the particular parcel of Real Estate showing the fair
         market value thereof (the "Appraised Value"). The appraisal must meet
         all applicable governmental requirements. The Appraised Value shown by
         such appraisal must be equal to or exceed the Purchase Price for such
         Real Estate. The appraiser will provide a reliance letter to MPT for
         each appraisal.

         SECTION 3.2.13 OTHER: Such other documents, certificates, and the like,
         as may be customary in comparable transactions or as MPT or MPT's legal
         counsel may otherwise reasonably require.

                                   ARTICLE IV

                             ADDITIONAL REQUIREMENTS

SECTION 4.1 EXPENSES: LESSEE shall reimburse MPT for all expenses incurred in
connection with this Commitment Letter, as well as the purchase, development,
and leaseback of any parcel of Real Estate; provided, however, that LESSEE will
not be required to reimburse any such expenses with respect to the Closing of a
particular Acquisition Facility or Development Facility if such Closing does not
occur as a result of MPT's failure to perform (unless such failure is as a
result of LESSEE'S failure to perform).

SECTION 4.2 MANAGEMENT: DSI or a management company approved by MPT will at all
times manage each Acquisition Facility and Development Facility unless written
approval is obtained from MPT or unless removed by MPT as provided for herein.
All management agreements shall be subordinate to the applicable Lease and may
be terminated by MPT in the event of a default under such Lease, and all fees
due and payable under all management agreements shall be subordinate to all
monetary obligations under such Lease.

SECTION 4.3 SIGNS: MPT shall have the right to erect a sign, approved by DSL,
which such approval shall not be unreasonably withheld, at the Acquisition or
Development Facilities stating that the Real Estate relating thereto is owned by
MPT.

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                                    ARTICLE V

                               GENERAL CONDITIONS

SECTION 5.1 REPRESENTATIONS OF THE LESSEE: MPT's obligations under this
Commitment Letter are subject to and contingent upon the accuracy and
completeness of all information, representations, and materials submitted with,
or in support of, this transaction and LESSEE'S strict and timely compliance
with all terms, conditions, and requirements set forth herein.

SECTION 5.2 RIGHT TO SELL: LESSEE understands MPT may sell its interest in any
parcel of Real Estate in whole or in part. LESSEE agrees that any purchaser may
exercise any and all rights of the landlord, as fully as if such had made the
purchase directly from the LESSEE. MPT may divulge to any purchaser all
information, reports, financial statements, certificates, and documents obtained
by it from the LESSEE.

SECTION 5.3 ENTIRE AGREEMENT, MODIFICATIONS, AND AMENDMENTS: This Commitment
Letter and the Confidentiality Agreement described in Section 5.8 hereof contain
the entire agreement of LESSEE and MPT with respect to the transaction described
herein and supersede any prior or contemporaneous understanding or commitment.
MPT has made no representations to the LESSEE that are not set forth in this
Commitment Letter. No changes in this Commitment Letter shall be binding unless
in writing and executed by the party against whom enforcement of the change is
sought.

SECTION 5.4 TIME: Time is of the essence with respect to all dates and periods
of time set forth in this Commitment Letter.

SECTION 5.5 ACCEPTANCE OF COMMITMENT: Upon return by LESSEE to MPT of a fully
executed copy of this commitment by the time set forth below, this Commitment
Letter will constitute an agreement of the LESSEE to consummate the Line terms
and conditions set forth herein. If said executed copy of this Commitment Letter
is not received by MPT by 5:00 p.m. Central Time on January 31, 2005 this
Commitment Letter shall be null and void and of no further force and effect
unless extended in writing by MPT.

SECTION 5.6 NONSOLICITATION: In consideration of the substantial expenditures of
time, effort, and expense to be undertaken by MPT and its representatives in
connection with its due diligence investigation and review of DSI, during the
period from the date of this Commitment Letter until the earlier of (i) the date
of execution of definitive agreements relating to the Line and (ii) April 30,
2005, neither DSI, nor any officer, director, member, partner, employee or agent
of DSI shall, directly or indirectly, solicit, seek, enter into, conduct, or
participate in any discussions or negotiations or enter into any agreement with
any other prospective person or entity, regarding a development and acquisition
facility similar to the Line.

SECTION 5.7 MPT SECURITIES OFFERING: Notwithstanding any other agreement of the
parties, in connection with its public offering or private placement of its
securities, MPT may disclose that it has entered into this Commitment Letter
with DSI respecting the Line and the acquisition of particular

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                                       11
<PAGE>

Acquisition or Development Facilities and may provide other information
regarding DSI, the Line, the Real Estate, and any Acquisition Facility or
Development Facility to its proposed investors in such public offering or
private offering of its securities.

SECTION 5.8 CONFIDENTIALITY: The parties reaffirm the existence and validity of
that certain confidentiality agreement between MPT and DSI dated August 8, 2004
(the "Confidentiality Agreement") and agree to continue to comply with all of
the terms and provisions thereof.

SECTION 5.9 ASSIGNMENT: This Commitment Letter and all rights of the parties
hereunder shall not be assigned by any party without the prior written approval
of the other parties; provided, however, that any party may assign its rights
and obligations hereunder to any entity controlling, controlled by or under
common control with the other; provided, however, that no such assignment shall
relieve any party of any liability hereunder.

SECTION 5.10 COUNTERPARTS: This Commitment Letter may be executed and delivered
by telecopy and in counterparts. Each counterpart when executed and delivered
shall be deemed an original, but together shall constitute one and the same
document.

SECTION 5.11 EXHIBITS: The exhibits indicated below are attached hereto and by
this reference made a part hereof:

           Exhibit A - Title insurance policy requirements.
           Exhibit B - Insurance Requirements
           Exhibit C - Surveyor's Certificate requirements

SECTION 5.12 NON-DISTURBANCE: MPT agrees that it will not grant a security
interest with respect to any parcel of Real Estate unless the grantee of such
security interest acknowledges in writing, in a form reasonably acceptable to
LESSEE and such grantee, that LESSEE'S rights under the applicable Lease
(including specifically the right to occupy the Real Estate and operate the
business thereon as provided in the Leases) will not be disturbed so long as
LESSEE is not in default under the terms of the Lease.

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Please indicate acceptance of the terms and conditions set forth in this
Commitment Letter by signing a copy of this Commitment Letter below.

                                   Sincerely,


                                   MPT OPERATING PARTNERSHIP, L.P.

                                   By: /s/ R. Steven Hamner
                                       ---------------------------
                                       R. Steven Hamner
                                       Executive Vice President and CFO

ACCEPTED AND AGREED TO:


DIVERSIFIED SPECIALTY INSTITUTES, INC.


/s/ Jerome S. Tannenbaum, M.D., Ph.D., FACP
-------------------------------------------
Jerome S. Tannenbaum, M.D., Ph.D., FACP
Chairman and Chief Executive Officer


Dated: March 3, 2005

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<PAGE>

                                    EXHIBIT A

                          TITLE INSURANCE REQUIREMENTS

MPT Operating Partnership. L.P., as Purchaser
Title Insurance Requirements

1.       "Title Policy" means a title insurance policy in American Land Title
Association "ALTA") 1992 form, or such other form as may be approved by
LESSOR, issued by a title insurer approved by LESSOR with reinsurance as
required by LESSOR to be on ALTA Facultative Reinsurance Agreement (rev 4/6/90)
such that the maximum single risk assumed by any single title insurer may not
exceed 25% of that company's capital, surplus, and statutory reserves. Each
title insurer issuing insurance required hereby must be licensed to insure
properties in the jurisdictions in which the Facilities are located.

2.       Owner's Title Policy. The amount of the owner's title insurance policy
on each Facility must equal the Purchase Price. The policy must insure against
ail standard exceptions (e.g., parties in possession, matters shown on public
records, matters which an accurate survey would show, and real estate taxes
currently due) and must be effective as of the date of the Closing. The title
policy must include such affirmative insurance endorsements as LESSOR may
require, to the extent not prohibited by the laws or insurance regulations of
the state where each Facility is located, including, without limitation, a
zoning compliance endorsement, a street access endorsement, a comprehensive
(ALTA Form 9) endorsement, a "Fairways" (change of partners) endorsement, an
endorsement negating imputation of knowledge to LESSOR, an endorsement that each
Facility is assessed for real estate taxes separate from any other property
(i.e., the property consists of a single tax lot and is not part of a larger tax
lot).


<PAGE>

                                    EXHIBIT B

                             INSURANCE REQUIREMENTS

I.       GENERAL REQUIREMENTS

The General Requirements set forth herein shall be applicable to the insurance
requirements outlined below in Paragraphs II and III throughout the term of this
Commitment Agreement.

         (A)      RELATING TO INSURER.

         All insurance coverages required by the Commitment Letter must be
provided by insurance companies acceptable to MPT that are rated at least an "A,
VII" or better by Best's Insurance Guide and Key Ratings and a claim payment
rating by Standard & Poor's Corporation of A or better. The aggregate amount of
coverage provided by a single company must not exceed 5% of the company's
policyholders' surplus. All insurance companies must be licensed and qualified
to do business in the state where the insured collateral is located.

         Each insurance policy must (i) provide primary insurance without right
of contribution from any other insurance carried by MPT, (ii) contain an express
waiver by the insurer of any right of subrogation, setoff or counterclaim
against any insured party thereunder including MPT, (iii) permit MPT to pay
premiums at MPT's discretion and (iv) as respects any third party liability
claim brought against MPT, obligate the insurer to defend MPT as an additional
insured thereunder.

         (B)      RELATING TO DOCUMENTATION OF COVERAGE.

         The original copy of each insurance policy required hereunder shall be
furnished to MPT, or in the case of a blanket policy, a copy of the original
policy certified in writing by a duly authorized Agent for the insurance company
as a "true and certified" copy of the policy. LESSEE shall not submit a
Certificate of Insurance, in lieu of the certified copy of the policy. The
original policy(ies) or certified copy of the policy(ies) must be delivered to
MPT, effective with the commencement of each of the Facilities and furnished
annually thereafter, prior to the expiration date of the preceding policy(ies).

         (C)      CANCELLATION AND MODIFICATION CLAUSE.

         1.       The insurer hereby agrees that its policy will not lapse,
terminate, or be canceled, or be amended or modified to reduce limits or
coverage terms unless and until MPT has received not less than sixty (60) days'
prior written notice thereof at the following address:

         MPT Operating Partnership, LP
         Attention; Its: President
         1000 Urban Center Drive, Suite 501
         Birmingham, Alabama 35242

         2.       Notwithstanding the foregoing, in the event of cancellation
due to non-payment of premium, the insurer shall provide not less than ten (10)
days' Notice of Cancellation to:

         MPT Operating Partnership, LP
         Attention: Its: President
         1000 Urban Center Drive, Suite 501
         Birmingham, Alabama 35242


<PAGE>

II.      TYPES OF INSURANCE

         LESSEE will at all times keep the Facilities insured against loss or
damage from such causes as are customarily insured against, by prudent owners of
similar Facilities. Without limiting the generality of the foregoing, LESSEE
will obtain and maintain in effect the following amounts and types of insurance
on each of the Facilities throughout the term of the Leases:

         (A)      "ALL RISKS" or "SPECIAL" FORM PROPERTY INSURANCE.

         All Risks or Special Form Property insurance against loss or damage to
the building and improvements, including but not limited to, perils of fire,
lightning, water, wind, theft, vandalism and malicious mischief, plate glass
breakage, and perils typically provided under an Extended Coverage Endorsement
and other forms of broadened risk perils, and insured on a "replacement cost"
value basis to the extent of the full replacement value of the Facility. The
deductible amount thereunder shall be borne by LESSEE in the event of a loss and
the deductible must not exceed $10,000 per occurrence. Further, in the event of
a loss, LESSEE shall abide by all provisions of the insurance contract,
including proper and timely notice of the loss to the insurer, and LESSEE
further agrees it will notify MPT of any loss in the amount of $25,000 or
greater and that no claim at or in excess of $25,000 thereunder shall be settled
without the prior written consent of MPT, which consent shall not be
unreasonably withheld or delayed by MPT.

         (B)      FLOOD AND EARTHQUAKE INSURANCE (Required only in the event
that the property is in a flood plain or earthquake zone).

         Insurance in an amount equal to the full replacement cost value of the
Facility, subject to no more than a $25,000 per occurrence, deductible. The
policy shall include coverage for subsidence.

         (C)      LOSS OF EARNINGS INSURANCE.

         Insurance against loss of earnings in an amount sufficient to cover not
less than 12 months' lost earnings and written in an "all risks" form, either as
an endorsement to the insurance required under Paragraph II(A), or under a
separate policy.

         (D)      WORKERS COMPENSATION INSURANCE.

         Workers Compensation insurance covering all employees in amounts that
are customary for LESSEE'S industry.

         (E)      LIABILITY INSURANCE.

         COMMERCIAL GENERAL LIABILITY: Commercial General Liability in a primary
amount of at least $5,000,000 per occurrence. Bodily Injury for injury or death
of any one person and $100,000 for Property Damage for damage to or loss of
property of others, subject to a $10,000,000 annual aggregate policy limit for
all Bodily Injury and Property Damage claims, occurring on or about the Land or
in any way related to the Project, including but not limited to, any swimming
pools or other recreational Facility or areas that are located on the Land or
otherwise related to the Facility. Such policy shall include coverages of a
Broad Form nature, including, but not limited to, Explosion, Collapse and
Underground (XCU). Products Liability, Completed Operations, Broad Form
Contractual Liability, Broad Form Property Damage, Personal Injury, Incidental
Malpractice Liability, and Host Liquor Liability.

         VEHICLE LIABILITY: Automobile and Vehicle Liability insurance coverage
for all owned, non-owned, leased or hired automobiles and vehicles in a primary
limit amount of $1,000,000 per occurrence for Bodily Injury; $100,000 per
occurrence for Property Damage; subject to an annual aggregate policy limit of
$1,000,000.


<PAGE>

         UMBRELLA LIABILITY: Umbrella Liability insurance in the minimum amount
of $10,000,000 for each occurrence and aggregate combined single limit for all
liability, with a $10,000 self-insured retention for exposure not covered in
underlying primary policies. The Umbrella Liability policy shall name in its
underlying schedule the policies of Professional Liability, Commercial General
Liability, Garage Keepers Liability, Automobile/Vehicle Liability and Employer's
Liability under the Workers Compensation Policy.

         PROFESSIONAL LIABILITY: NOTE: WE ARE DISCUSSING THIS COVERAGE WITH OUR
CONSULTANTS. Professional Liability insurance for LESSEE and any physician or
other employee or agent of LESSEE providing services at the Facility in an
amount not less than five million dollars ($5,000,000) per individual claim and
ten million dollars ($10,000,000) annual aggregate.

         (F)      COMMERCIAL BLANKET FIDELITY BOND INSURANCE.

         A Commercial Blanket Bond covering all employees of the Borrower,
including its officers, and the individual owners of the insured business
entity, whether a joint-venture, partnership, proprietorship or incorporated
entity, against loss as a result of their dishonesty. Policy limit shall be in
an amount of at least $1,000,000, subject to a deductible of no more than
$10,000 per occurrence.


<PAGE>

                                    EXHIBIT C

                             SURVEYOR'S CERTIFICATE

The undersigned hereby certifies to Medical Properties Trust, Inc and__________
______________________ (the "Title Insurance Company"): (a) that he is a duly
registered land surveyor in the State of ______________________; (b) that the
plat to which this certificate is affixed (the "Plat") is a true, complete and
correct survey of the property described therein (the "Property") being
approximately _____ acres as further described by the Property Description on
the Plat; (c) the Plat is based upon a field survey made _______, _____, by me
or directly under my supervision in accordance with the minimum standards
established by the State of _______________ for surveyors and with the "Minimum
Standard Detail Requirements for ALTA/ACSM Land Title Surveys" jointly
established and adopted by ALTA and ACSM in 1992 and meets the Accuracy
Standards (as adopted by ALTA and ACSM in 1992 and in effect on the date of this
certification) of an Urban Survey, and contains items 1, 2, 3, 4, 7(a), 8, 9,
10, 11(a), and 11(b) of Table A thereto; (d) that the Plat correctly shows the
location of all buildings, structures and other improvements on the Property;
(e) that the Plat correctly shows the location of all easements, restrictions
and rights-of-way described in title insurance commitment number _________
effective as of ________, 1997 issued by the Title Insurance Company (the
"Title Commitment"); (f) that the legal description set forth in the Title
Commitment is identical in all respects to the Property Description set forth on
the Plat; (g) except as shown on the Plat there are no discrepancies between the
boundary lines of the Property as shown on the Plat and as described in the
legal description of record; (h) that the Plat easements indicate existing
surface and underground transmission lines or utilities, such as natural gas,
telephone, telegraph, TV cable, water, sewage and electrical power, including
pipeline type and sizes with all utility pole locations with overhead wires
indicated and the nearest available services clearly shown and dimensional: (i)
that, except as shown on the Plat, there are (1) no visible easements or
rights-of-way on the Property or any other easements or rights-of-way thereon of
which the undersigned has knowledge. (2) no party walls on the Property. (3) no
encroachments from the Property over adjoining premises, streets or roads by any
buildings, structures or other improvements located on the Property, and (4) no
encroachments on the Property by any buildings, structures or other improvements
located on adjoining property; (j) that the boundary line dimensions as shown on
the Plat form a mathematically closed figure within +/- 0.01 foot; (k) that the
boundary lines of the Property are contiguous with the boundary lines of all
adjoining parcels, roads, highways, streets or alleys as described in their most
recent respective legal description of record; (1) that the buildings,
structures and other improvements located on the Property do not violate any
building or setback lines; (m) that adequate ingress to and egress from the
Property is provided by _____________, the same being paved, dedicated public
rights-of-way maintained by ____________________ (name of maintaining
authority); and (n) that the undersigned has consulted the National Flood
Insurance Program Maps and has found that, in accordance with said maps, Panel
Number________, dated______________________, no portion of the Property lies
within a flood hazard area, except as depicted on the Plat.

                      (Name of Surveyor. Registration No.)