title: The efficacy of a lysine-based dendritic hydrogel does not differ from those of commercially available tissue sealants and adhesives: an ex vivo study.
abstract: BACKGROUND
  Hemostatic agents, tissue adhesives and sealants may contribute to a reduction in hemorrhage-associated morbidity and mortality. Towards this end, we have recently developed a lysine-based dendritic hydrogel (PEG-LysNH2) that can potentially be used in the management of severe trauma and/or intraoperative bleeding. As a first step in demonstrating the potential utility of this approach, our objective was to ascertain the ability of the PEG-LysNH2 to adhere to and seal injured tissues, as well as to maintain the seal under physiological conditions.
  
  
  METHODS
  The efficacy of the PEG-LysNH2 in sealing injured tissues was evaluated using an ex-vivo pressure testing system. A 2.5 mm incision was made on intact ex-vivo tissues and then sealed with the PEG-LysNH2. Application of the PEG-LysNH2 was followed by 1) step-wise pressure increase to a maximum of 250 mmHg and 2) fluctuating pressures, between 100-180 mmHg with a rate of 3 Hz, over a 24-hour period. The performance of the PEG-LysNH2 was compared to those of commercially available sealants and adhesives.
  
  
  RESULTS
  During gradual pressure increase, mean pressures at 30 seconds (P30) ranged between 206.36 - 220.17 mmHg for the sealants, and they were greater than control and suture groups (p < 0.01 and p = 0.013, respectively). Additionally, all products held under fluctuating pressures: mean pressures ranged between 135.20 - 160.09 mmHg, and there were no differences observed between groups (p = 0.96).
  
  
  CONCLUSIONS
  The efficacy of the PEG-LysNH2 was significantly superior to conventional injury repair methods (sutures) and did not differ from those of commercially available products when sealing small incisions.
authors.affiliation: Center for Advanced Orthopaedic Studies, Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA. jvilla@bidmc.harvard.edu.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Villa-Camacho
authors.affiliation: Departments of Biomedical Engineering and Chemistry, Boston University, Boston, MA, USA. ghobril@bu.edu.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Ghobril
authors.affiliation: Center for Advanced Orthopaedic Studies, Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA. lanezbus@bidmc.harvard.edu.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Anez-Bustillos
authors.affiliation: Departments of Biomedical Engineering and Chemistry, Boston University, Boston, MA, USA. mgrin@bu.edu.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Grinstaff
authors.affiliation: Carl J Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA. ekrodrig@bidmc.harvard.edu.
authors.forename: Edward K
authors.initials: EK
authors.lastname: Rodríguez
authors.affiliation: Center for Advanced Orthopaedic Studies, Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA. anazaria@bidmc.harvard.edu.
authors.forename: Ara
authors.initials: A
authors.lastname: Nazarian
mesh_terms: D000268:Adhesiveness; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000293:injuries / Q000503:physiopathology; D002417:Cattle; D003487:Cyanoacrylates / Q000494:pharmacology; D050091:Dendrimers / Q000737:chemistry / Q000494:pharmacology*; D004659:Enbucrilate / Q000494:pharmacology; D015718:Fibrin Tissue Adhesive / Q000494:pharmacology; D006490:Hemostatics / Q000737:chemistry / Q000494:pharmacology*; D020100:Hydrogels; D066298:In Vitro Techniques; D008239:Lysine / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology*; D008422:Materials Testing; D051379:Mice; D011092:Polyethylene Glycols / Q000737:chemistry / Q000494:pharmacology*; D011312:Pressure; D011506:Proteins / Q000494:pharmacology; D012212:Rheology; D012867:Skin / Q000187:drug effects / Q000503:physiopathology; D013314:Stress, Mechanical; D013997:Time Factors; D014014:Tissue Adhesives / Q000737:chemistry / Q000494:pharmacology*; D057772:Vascular System Injuries / Q000188:drug therapy / Q000503:physiopathology
chemical_list: C472676:Bio-glue; D003487:Cyanoacrylates; D050091:Dendrimers; D015718:Fibrin Tissue Adhesive; D006490:Hemostatics; D020100:Hydrogels; D011506:Proteins; D014014:Tissue Adhesives; D011092:Polyethylene Glycols; C100832:octyl 2-cyanoacrylate; D004659:Enbucrilate; D008239:Lysine