Vascular embolic system

Abstract

Systems and methods of blocking a biological vessel 2 are provided. The systems and methods may comprise introducing to the vessel an amphiphilic peptide. The peptide may comprise at least thirteen amino acids that may alternate between a hydrophobic amino acid and a hydrophilic amino acid. The peptide may form a beta- sheet spontaneously in an aqueous solution in the presence of a cation.

1 . A method of blocking one or more targeted biological vessels in a subject comprising:
 introducing a catheter into a target biological vessel;   positioning an end of the catheter in, near, upstream or downstream from a target area of a biological vessel in which at least a partial obstruction of the vessel is desired;   administering through the catheter a solution comprising an amphiphilic peptide comprising at least 12 amino acids that alternate between a hydrophobic amino acid and a hydrophilic amino acid in an effective amount and in an effective concentration to form a hydrogel at the target site the hydrogel thereby forming at least a partial blockage of the target biological vessel;   removing the catheter from the biological vessel with the at least partial obstruction in place.   
     
     
         2 . The method of  claim 1 , wherein the peptide solution comprises a contrast agent. 
     
     
         3 . The method of  claim 2 , further comprising visualizing a region comprising at least a portion of the targeted biological vessel or vessels. 
     
     
         4 . The method of  claim 3 , wherein visualizing the region comprising at least a portion of the biological vessel comprises visualizing the region during at least one of:
 identifying the target area of the biological vessel;   introducing the catheter;   positioning the end of the catheter in the target area;   administering the solution;   removing the catheter; and   visualizing the biological vessel after removing the catheter.   
     
     
         5 . The method of  claim 4 , wherein visualizing the region comprises imaging using X-ray radiography. 
     
     
         6 . The method of  claim 3 , wherein visualizing the region provides for selective administration of the solution to a targeted biological vessel. 
     
     
         7 . The method of  claim 3 , further comprising visualizing a previously targeted region of a vessel in a time period about two weeks subsequent to administration of a peptide solution. 
     
     
         8 . The method of  claim 1 , wherein at least one of the effective amount, the effective concentration and the identity of the peptide is based in part on the diameter of the target area of the biological vessel. 
     
     
         9 . The method of  claim 1 , wherein at least one of the effective amount, the effective concentration and the identity of the peptide is based in part on the flow rate of the blood in the biological vessel. 
     
     
         10 . (canceled) 
     
     
         11 . The method of  claim 1 , wherein the concentration effective to form at least a partial blockage of the target biological vessel comprises a concentration in a range of about 0.1 weight per volume (w/v) percent to about 3 w/v percent peptide. 
     
     
         12 . The method of  claim 1 , wherein the amount effective to cause at least partial blockage of the biological vessel comprises a volume in a range of about 0.1 mL to about 5 mL. 
     
     
         13 . The method of  claim 1 , further comprising monitoring the area surrounding the at least partial blockage comprising the self-assembled peptide hydrogel to determine an effectiveness of the at least partial obstruction in treating the subject's pathology. 
     
     
         14 . The method of  claim 1 , wherein the formed blockage is used in the treatment of disorders, malformations, or congenital ailments in one or more biological vessels. 
     
     
         15 . The method of  claim 14 , wherein the formed blockage is used in the treatment of one of patent ductus arteriosus (PDA) and major aortopulmonary collateral artery (MAPCA). 
     
     
         16 . The method of  claim 14 , wherein the formed blockage is used in the treatment of a disorder, malformation, or congenital ailment selected from the group consisting of recurrent hemolysis, arteriovenous malformations, cerebral aneurysms, gastrointestinal bleeding, epistaxis, post-partum hemorrhage, surgical hemorrhage, and uterine fibroids. 
     
     
         17 . The method of  claim 1 , wherein the formed blockage is used in the reduction of the size and/or number of cancerous cells. 
     
     
         18 - 21 . (canceled) 
     
     
         22 . The method of  claim 1 , wherein administering the solution comprises administering the solution in a single dose. 
     
     
         23 . The method of  claim 1 , wherein treatment of the subject comprises administering one or more doses of the same or a different solution of peptide in separate applications. 
     
     
         24 . The method of  claim 1 , wherein the peptide has an amino acid sequence of one of RADARADARADARADA (SEQ ID NO: 7), IEIKIEIKIEIKI (SEQ ID NO: 8), and IEIKIEIKIEIKIEIKI (SEQ ID NO: 9). 
     
     
         25 - 53 . (canceled) 
     
     
         54 . The method of  claim 1  wherein the subject is heparinized, on other anticoagulation therapy and/or in which normal coagulation is impaired.