% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@ARTICLE{Boschert:862127,
      author       = {Boschert, Alessa and Elmenhorst, David and Gauger, Peter
                      and Li, Zhili and Garcia-Gutierrez, Maria T. and Gerlach,
                      Darius and Johannes, Bernd and Zange, Jochen and Bauer,
                      Andreas and Rittweger, Jörn},
      title        = {{S}leep is compromised in -12° head down tilt position},
      journal      = {Journal of sleep research},
      volume       = {10},
      issn         = {1365-2869},
      publisher    = {Frontiers in Physiology},
      reportid     = {FZJ-2019-02483},
      pages        = {397},
      year         = {2019},
      abstract     = {Recent studies are elucidating the interrelation between
                      sleep, cranial perfusion, and cerebrospinal fluid (CSF)
                      circulation. Head down tilt (HDT) as a simulation of
                      microgravity reduces cranial perfusion. Therefore, our aim
                      was to assess whether HDT is affecting sleep
                      (clinicaltrials.gov; identifier NCT 02976168). 11 male
                      subjects were recruited for a cross-over designed study.
                      Each subject participated in two campaigns each comprising 3
                      days and 2 nights. Intervention started on the second
                      campaign day and consisted of maintenance of horizontal
                      position or −12° HDT for 21 h. Ultrasound measurements
                      were performed before, at the beginning and the end of
                      intervention. Polysomnographic measurements were assessed in
                      the second night which was either spent in horizontal
                      posture or at −12° HDT. Endpoints were sleep efficiency,
                      sleep onset latency, number of sleep state changes and
                      arousals, percentages of N3, REM, light sleep stages and
                      subjective sleep parameters. N3 and REM sleep reduced by
                      25.6 and 19.1 min, respectively (P = 0.002, g = -0.898; P =
                      0.035, g = -0.634) during −12° HDT. Light sleep (N1/2)
                      increased by 33.0 min at −12° HDT (P = 0.002, g = 1.078).
                      On a scale from 1 to 9 subjective sleep quality deteriorated
                      by 1.3 points during −12° HDT (P = 0.047, g = -0.968).
                      Ultrasonic measurement of the venous system showed a
                      significant increase of the minimum (P = 0.009, P < 0.001)
                      and maximum (P = 0.004, P = 0.002) cross-sectional area of
                      the internal jugular vein at −12° HDT. The minimum
                      cross-sectional area of the external jugular vein differed
                      significantly between conditions over time (P = 0.001)
                      whereas frontal skin tissue thickness was not significantly
                      different between conditions (P = 0.077, P = 0.811). Data
                      suggests venous congestion at −12° HDT. Since subjects
                      felt comfortable with lying in −12° HDT under our
                      experimental conditions, this posture only moderately
                      deteriorates sleep. Obviously, the human body can almost
                      compensate the several fold effects of gravity in HDT
                      posture like an affected CSF circulation, airway
                      obstruction, unusual patterns of propioception and effects
                      on the cardiovascular system.},
      cin          = {INM-2},
      ddc          = {610},
      cid          = {I:(DE-Juel1)INM-2-20090406},
      pnm          = {573 - Neuroimaging (POF3-573)},
      pid          = {G:(DE-HGF)POF3-573},
      typ          = {PUB:(DE-HGF)16},
      pubmed       = {pmid:31040791},
      UT           = {WOS:000465090600001},
      doi          = {10.3389/fphys.2019.00397},
      url          = {https://juser.fz-juelich.de/record/862127},
}