title: A Single Controlled Exposure to Secondhand Smoke May Not Alter Thrombogenesis or Trigger Platelet Activation.
abstract: BACKGROUND
  Chronic secondhand smoke (SHS) exposure increases cardiovascular events, particularly acute thrombotic events. There are little human data on acute SHS exposure. The aim of this study was to determine whether a single controlled exposure of humans to SHS increased thrombogenesis.
  
  
  METHODS
  After 6-8 hours fast, subjects (n = 50) were exposed to constant dose SHS (particulate level of 500 μg/m(3)) for 120 minutes in a temperature-regulated and ventilated, simulated bar environment. Blood was drawn before and immediately after SHS exposure for thromboelastography (TEG) and flow cytometry. Maximum clot strength (MA) was measured using TEG and platelet leukocyte aggregates (LPA) were measured as an index of platelet activation. Anti-CD 14 antibodies were used as leukocyte markers and anti-CD 41 antibodies as platelet markers for cytometry. Data were analyzed using students' t test for paired samples.
  
  
  RESULTS
  There was no effect of acute exposure to SHS on platelet activation or thrombogenesis. Also, intra group (smokers [n = 19] and nonsmokers [n = 31]) comparisons of LPA and TEG parameters did not show changes with SHS exposure.
  
  
  CONCLUSIONS
  While there are abundant data showing enhanced thrombogenesis and platelet activation following repeated exposure to SHS, our study suggests that a single exposure does not appear to significantly alter thrombin kinetics nor result in platelet activation. The effects of SHS on thrombogenesis might be nonlinear.
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Sundararajan
authors.initials: S
authors.lastname: Srikanth
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Fridolin
authors.initials: F
authors.lastname: Sy
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Kamal
authors.initials: K
authors.lastname: Kotak
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Richard G
authors.initials: RG
authors.lastname: Kiel
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Bajwa
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Abishek
authors.initials: A
authors.lastname: Tandon
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Andreia A
authors.initials: AA
authors.lastname: Loures-Vale
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Waqqas
authors.initials: W
authors.lastname: Aftab
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA.
authors.forename: Steven
authors.initials: S
authors.lastname: Tringali
authors.affiliation: Division of Cardiovascular Medicine, University of California San Francisco, Fresno, CA jamambrose@yahoo.com.
authors.forename: John A
authors.initials: JA
authors.lastname: Ambrose
mesh_terms: D000328:Adult; D015415:Biomarkers; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation / Q000187:drug effects*; D013916:Thrombelastography; D013927:Thrombosis / Q000139:chemically induced*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects / Q000032:analysis; D055815:Young Adult
chemical_list: D015415:Biomarkers; D014028:Tobacco Smoke Pollution