title: Preliminary comparative analysis of antibacterial effects of activated and non-activated of expired platelet concentrate by disc diffusion method.
abstract: BACKGROUND
  Platelets release more than 30 cytokines to provide primary hemostatic function. In addition, platelets are also known to release antimicrobial peptides upon activation by thrombin.
  
  
  METHODS
  In this study, comparative analysis of antibacterial activity of activated and non-activated expired platelet concentrate was determined against Gram-positive and Gram-negative bacteria by Kirby-Bauer disk diffusion method. Thrombin was used to prepare activated platelet concentrate. Gram-positive bacteria tested in this study were S.aureus and S.pyogenes and Gram-negative bacteria were E.coli and K.oxytoca. All the bacteria used in this study were sensitive strains from clinical isolates. Activated and non-activated platelet showed no zone of inhibition against S.pyogenes and E.coli.
  
  
  RESULTS
  Activated platelet showed antibacterial activity against S.aureus and K.oxytoca with the zone of inhibition of 8.3 ± 0.6 mm and 7.7 ± 0.2 mm, respectively. Zone of inhibition observed in non-activated platelet against S.aureus and K.oxytoca were 7.8 ± 0.4 mm and 7.5 ± 0.3 mm, respectively.
  
  
  CONCLUSIONS
  These findings showed that no significant differences in antibacterial activity produced by activated and non-activated platelet. However, zone of inhibition observed in activated and non-activated platelet indicate the presence of antibacterial property in expired platelet.
authors.affiliation: Advanced Medical and Dental Institute, Universiti Sains Malaysia, Penang, Malaysia.
authors.forename: Muhammad Azrul
authors.initials: MA
authors.lastname: Zabidi
authors.forename: Narazah Mohd
authors.initials: NM
authors.lastname: Yusoff
authors.forename: Zainoodin Sheik Abdul
authors.initials: ZS
authors.lastname: Kader
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000378:metabolism* / Q000494:pharmacology*; D001792:Blood Platelets / Q000737:chemistry*; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D006801:Humans; D008826:Microbial Sensitivity Tests
chemical_list: D023181:Antimicrobial Cationic Peptides