title: Association of microparticles and neutrophil activation with decompression sickness.
abstract: Decompression sickness (DCS) is a systemic disorder, assumed due to gas bubbles, but additional factors are likely to play a role. Circulating microparticles (MPs)--vesicular structures with diameters of 0.1-1.0 μm--have been implicated, but data in human divers have been lacking. We hypothesized that the number of blood-borne, Annexin V-positive MPs and neutrophil activation, assessed as surface MPO staining, would differ between self-contained underwater breathing-apparatus divers suffering from DCS vs. asymptomatic divers. Blood was analyzed from 280 divers who had been exposed to maximum depths from 7 to 105 meters; 185 were control/asymptomatic divers, and 90 were diagnosed with DCS. Elevations of MPs and neutrophil activation occurred in all divers but normalized within 24 h in those who were asymptomatic. MPs, bearing the following proteins: CD66b, CD41, CD31, CD142, CD235, and von Willebrand factor, were between 2.4- and 11.7-fold higher in blood from divers with DCS vs. asymptomatic divers, matched for time of sample acquisition, maximum diving depth, and breathing gas. Multiple logistic regression analysis documented significant associations (P < 0.001) between DCS and MPs and for neutrophil MPO staining. Effect estimates were not altered by gender, body mass index, use of nonsteroidal anti-inflammatory agents, or emergency oxygen treatment and were modestly influenced by divers' age, choice of breathing gas during diving, maximum diving depth, and whether repetitive diving had been performed. There were no significant associations between DCS and number of MPs without surface proteins listed above. We conclude that MP production and neutrophil activation exhibit strong associations with DCS.
authors.affiliation: Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, Maryland; sthom@smail.umaryland.edu.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Thom
authors.affiliation: Department of Diving and Hyperbaric Medicine, Prince of Wales Hospital, New South Wales, Australia;
authors.forename: Michael
authors.initials: M
authors.lastname: Bennett
authors.affiliation: Department of Hyperbaric Medicine, Fiona Stanley Hospital, Perth, Western Australia;
authors.forename: Neil D
authors.initials: ND
authors.lastname: Banham
authors.affiliation: Department of Hyperbaric Medicine, University of California Los Angeles Medical Center, Los Angeles, California;
authors.forename: Walter
authors.initials: W
authors.lastname: Chin
authors.affiliation: Department of Emergency Medicine, The Townsville Hospital and College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland, Australia;
authors.forename: Denise F
authors.initials: DF
authors.lastname: Blake
authors.affiliation: Sahlgrenska University Hospital/Omrade2, Gothenburg, Sweden;
authors.forename: Anders
authors.initials: A
authors.lastname: Rosen
authors.affiliation: Divers Alert Network, Durham, North Carolina;
authors.forename: Neal W
authors.initials: NW
authors.lastname: Pollock
authors.affiliation: Department of Integrative Physiology, University of Split School of Medicine, Soltanska, Split, Croatia;
authors.forename: Dennis
authors.initials: D
authors.lastname: Madden
authors.affiliation: Department of Integrative Physiology, University of Split School of Medicine, Soltanska, Split, Croatia;
authors.forename: Otto
authors.initials: O
authors.lastname: Barak
authors.affiliation: Divers Alert Network Europe Foundation and Diving Safety Laboratory, Roseto, Italy;
authors.forename: Alessandro
authors.initials: A
authors.lastname: Marroni
authors.affiliation: Divers Alert Network Europe Foundation and Diving Safety Laboratory, Roseto, Italy; Environmental, Occupational, Ageing and Integrative Physiology Laboratory, Haute Ecole Paul-Henri Spaak, Brussels, Belgium;
authors.forename: Costantino
authors.initials: C
authors.lastname: Balestra
authors.affiliation: Centre for Hyperbaric Oxygen Therapy, Military Hospital Brussels, Brussels, Belgium; and.
authors.forename: Peter
authors.initials: P
authors.lastname: Germonpre
authors.affiliation: Divers Alert Network Europe Foundation and Diving Safety Laboratory, Roseto, Italy;
authors.forename: Massimo
authors.initials: M
authors.lastname: Pieri
authors.affiliation: Divers Alert Network Europe Foundation and Diving Safety Laboratory, Roseto, Italy;
authors.forename: Danilo
authors.initials: D
authors.lastname: Cialoni
authors.affiliation: Department of Emergency Medicine, Pereleman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Phi-Nga Jeannie
authors.initials: PN
authors.lastname: Le
authors.affiliation: Department of Emergency Medicine, Pereleman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Christopher
authors.initials: C
authors.lastname: Logue
authors.affiliation: Department of Emergency Medicine, Pereleman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: David
authors.initials: D
authors.lastname: Lambert
authors.affiliation: Department of Emergency Medicine, Pereleman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Hardy
authors.affiliation: Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
authors.forename: Douglas
authors.initials: D
authors.lastname: Sward
authors.affiliation: Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.affiliation: Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
authors.forename: Veena B
authors.initials: VB
authors.lastname: Bhopale
authors.affiliation: Department of Integrative Physiology, University of Split School of Medicine, Soltanska, Split, Croatia;
authors.forename: Zeljko
authors.initials: Z
authors.lastname: Dujic
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D015992:Body Mass Index; D055252:Cell-Derived Microparticles / Q000378:metabolism*; D003665:Decompression Sickness / Q000188:drug therapy / Q000378:metabolism*; D004242:Diving / Q000502:physiology*; D005260:Female; D005740:Gases / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D018375:Neutrophil Activation / Q000187:drug effects / Q000502:physiology*; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D055815:Young Adult
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D005740:Gases; D010100:Oxygen
keywords: CD14; CD235; CD41; decompression sickness; myeloperoxidase; platelet-endothelial cell-adhesion molecule; tissue factor; von Willebrand factor