Exhibit 4.16


 


SIXTH AMENDMENT TO LETTER

LOAN AGREEMENT


 


This Sixth
Amendment to Letter Loan Agreement ("Sixth Amendment") is made and entered into effective as of January 8, 2012,
by and between FIRST STREET HOSPITAL, L.P., a Texas Limited Partnership (the "Borrower"), and THE BANK OF RIVER OAKS
(the "Lender").


 


RECITALS:


 


A.           Borrower
and Lender have previously executed a Letter Loan Agreement (the "Loan Agreement") dated January 8, 2008, covering
financial arrangements between Borrower and Lender as contained therein.


 


B.           Borrower
and Lender have previously modified the terms and provisions of the Loan Agreement by instruments dated June 1, 2008, January 8,
2009, January 8, 2010, January 8, 2011, and October 31, 2011, to which reference is hereby made for all purposes, and which instruments
are included in all references to the Loan Agreement.


 


C.           Borrower
and Lender have agreed to modify certain provisions of the Loan Agreement.


 


AGREEMENT:


 


NOW, THEREFORE,
in consideration of the mutual promises and agreements set forth herein, and other good and valuable consideration, the receipt
and legal sufficiency of which are hereby acknowledged, Borrower and Lender agree as follows:


 


1.          Recitals,
Definitions and References. The foregoing recitations are true and correct. Each of the terms used herein, which are not otherwise
defined or modified but which are defined in the Loan Agreement, shall have the meaning therein ascribed to them.


 


2.          Modification
of Loan Agreement. Section 1(b) of the Loan Agreement is modified to extend the Termination Date to January 8, 2013.


 


3.          Release
and Waiver of Claims. In consideration of (i) the modification of certain provisions of the Loan and Loan Documents, as herein
provided, and (ii) the other benefits received by Borrower hereunder, Borrower hereby RELEASES, RELINQUISHES and forever DISCHARGES
Lender, as well as its predecessors, successors, assigns, agents, officers, directors, employees and representatives, of and from
any and all claims, demands, actions and causes of action of any and every kind or character, past or present, which Borrower may
have against Lender and its predecessors, successors, assigns, agents, officers, directors, employees, and representatives arising
out of or with respect to (a) any right or power to bring any claim against Lender for usury or to pursue any cause of action against
Lender based on any claim of usury, and (b) any and all transactions relating to the Loan or Loan Documents, occurring prior to
the date hereof, including any loss, cost or damage, of any kind or character, arising out of or in any way connected with or in
any way resulting from the acts, actions or omissions of Lender, and its predecessors, successors, assigns, agents, officers, directors,
employees, and representatives, including any breach of fiduciary duty, breach of any duty of fair dealing, breach of confidence,
breach of funding commitment, undue influence, duress, economic coercion, conflict of interest, negligence, bad faith, malpractice,
intentional or negligent infliction of mention distress, tortuous interference with contractual relations, tortuous interference
corporate governance or prospective business advantage, breach of contract, deceptive trade practices, libel, slander, or conspiracy,
but in each case only to the extent permitted by applicable law.


 









    	 



    	 



    



 


4.          Reaffirmation
of Representations and Warranties. Borrower represents and warrants that (a) the representations and warranties contained in
the Loan Agreement are true and correct in all material respects as of the date of this Sixth Amendment, (b) no condition, act
or event which could constitute an Event of Default under the Loan Agreement exists, and (c) no condition, event, act or omission
has occurred, which, with the giving of notice or passage of time, would constitute an Event of Default under the Loan Agreement.


 


5.          Ratification
of Loan Agreement. In all other respects, the Loan Agreement, as amended by this Sixth Amendment, is ratified and confirmed.
All other terms and provisions of the Loan Agreement shall remain in full force and effect as originally executed or amended. In
the event there is a conflict between the terms and provisions of this Sixth Amendment and the Loan Agreement as originally executed
and/or amended, the terms and provisions of this Sixth Amendment shall control.


 


6.          Miscellaneous.
This Sixth Amendment (a) shall be binding upon and inure to the benefit of Borrower and Lender and their respective successors
and assigns; (b) may be modified or amended only by a writing signed by each party hereto; (c) may be executed by facsimile signatures
and in several or separate counterparts, and each counterpart, when so executed and delivered, shall constitute an original agreement,
and all such separate counterparts shall constitute but one and the same agreement; and (d) embodies the entire agreement and understanding
between the parties with respect to the subject matter hereof and supersedes all prior agreements, consents and understandings
in relating to the subject matter hereof. The headings in this Sixth Amendment shall be accorded no significance in interpreting
this instrument.


 


7.          Final
Agreement. THIS AGREEMENT REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.


 


EXECUTED effective for all purposes as of the date
first above written.


 





	 	BORROWER:
	 	 
	 	FIRST STREET HOSPITAL, L.P., a Texas limited partnership
	 	 
	 	By:	FIRST SURGICAL PARTNERS, L.L.C.,
	 	 	a Texas limited liability company,
	 	 	its General Partner
	 	 	 
	 	 	By:	/s/ Tony Rotondo
	 	 	Tony Rotondo, Member
	 	 	 
	 	 	By:	/s/ Jacob Varon, M.D.
	 	 	Jacob Varon, M.D., Member
	 	 	 
	 	 	LENDER
	 	 	 
	 	 	THE BANK OF RIVER OAKS
	 	 	 
	 	 	Name:	/s/Mark Troth
	 	 	Title:	President