title: Sealing effect of a polysaccharide nanosheet for murine cecal puncture.
abstract: BACKGROUND
  Recent developments in nanobiotechnology have led us to develop a method of producing a free-standing polymer nanosheet composed of polysaccharides (ie, polysaccharide nanosheet) with a thickness of tens of nanometers. Owing to its enormous aspect ratio, the polysaccharide nanosheet is semi-absorbent and has a physical adhesive strength 7.5-fold greater than that of conventional films of >1 microm thickness. Herein, we have investigated the therapeutic sealing effect of this polysaccharide nanosheet on murine cecal puncture as a wound dressing material.
  
  
  METHODS
  Murine cecum was punctured and then overlapped with the polysaccharide nanosheet. Thereafter, we evaluated its sealing effect on bacterial peritonitis as well as the protection offered by the polysaccharide nanosheet against bacterial permeability using an in vitro transmembrane assay.
  
  
  RESULTS
  The 39-nm-thick polysaccharide nanosheet overlapped tightly the perforated cecum. No adhering agents were required because of the ability of the polysaccharide nanosheet to adhere to the tissue surface by physical adsorption (eg, van der Waals interaction). Sealing the perforated cecum with the polysaccharide nanosheet increased survival rate without postoperative adhesion by comparison with untreated mice (90 vs 30%; P < .01). These data were supported by the improvement in peritonitis related to bacterial counts, white blood cell counts, and the serum tumor necrosis factor level. Moreover, using an in vitro transmembrane assay, we showed that the polysaccharide nanosheet inhibited effectively bacterial penetration.
  
  
  CONCLUSIONS
  We have demonstrated the potential clinical benefits of the nanosheet-type biomaterial that can be used for repairing a cecal colotomy without chemical bonding agents.
authors.affiliation: Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku, Tokyo, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Fujie
authors.forename: Manabu
authors.initials: M
authors.lastname: Kinoshita
authors.forename: Satoshi
authors.initials: S
authors.lastname: Shono
authors.forename: Akihiro
authors.initials: A
authors.lastname: Saito
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Okamura
authors.forename: Daizoh
authors.initials: D
authors.lastname: Saitoh
authors.forename: Shinji
authors.initials: S
authors.lastname: Takeoka
mesh_terms: D000818:Animals; D018988:Bacterial Translocation; D001458:Bandages; D002432:Cecum; D007958:Leukocyte Count; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D049329:Nanostructures; D010538:Peritonitis / Q000382:microbiology / Q000628:therapy*; D010539:Permeability; D011134:Polysaccharides / Q000627:therapeutic use*; D011677:Punctures; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D011134:Polysaccharides; D014409:Tumor Necrosis Factor-alpha