Selected scientific publications on diving medicine and physiology.

2012 Sep 26
Effect of tetrahydrobiopterin and exercise training on endothelium-dependent vasorelaxation in SHR_V2
Guerrero F, Thioub S, Goanvec C, Theunissen S, Feray A, Balestra C & Mansourati J.

We examined whether the improvement of impaired NO-dependent vasorelaxation by exercise training could be mediated through a BH4-dependent mechanism. Male spontaneously hypertensive rats (SHR, n = 20) and Wistar-Kyoto rats (WKY, n = 20) were trained (Tr) for 9 weeks on a treadmill and compared to age-matched sedentary animals (Sed). Endothelium-dependent vasorelaxation (EDV) was assessed with acetylcholine by measuring isometric tension in rings of femoral artery precontracted with 10(-5) M phenylephrine. EDV was impaired in SHR-Sed as compared to WKY-Sed (p = 0.02).

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2019 Jul 11
Static Metabolic Bubbles as Precursors of Vascular Gas Emboli During Divers' Decompression: A Hypothesis Explaining Bubbling Variability
Imbert JP, Egi SM, Germonpre P & Balestra C

Introduction: The risk for decompression sickness (DCS) after hyperbaric exposures (such as SCUBA diving) has been linked to the presence and quantity of vascular gas emboli (VGE) after surfacing from the dive. These VGE can be semi-quantified by ultrasound Doppler and quantified via precordial echocardiography. However, for an identical dive, VGE monitoring of divers shows variations related to individual susceptibility, and, for a same diver, dive-to-dive variations which may be influenced by pre-dive pre-conditioning. These variations are not explained by currently used algorithms. In this paper, we present a new hypothesis: individual metabolic processes, through the oxygen window (OW) or Inherent Unsaturation of tissues, modulate the presence and volume of static metabolic bubbles (SMB) that in turn act as precursors of circulating VGE after a dive.

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2017 Feb 1
Preconditioning to Reduce Decompression Stress in Scuba Divers
Germonpré P., Balestra C.

BACKGROUND: Using ultrasound imaging, vascular gas emboli (VGE) are observed after asymptomatic scuba dives and are considered a key element in the potential development of decompression sickness (DCS). Diving is also accompanied with vascular dysfunction, as measured by flow-mediated dilation (FMD). Previous studies showed significant intersubject variability to VGE for the same diving exposure and demonstrated that VGE can be reduced with even a single pre-dive intervention. Several preconditioning methods have been reported recently, seemingly acting either on VGE quantity or on endothelial inflammatory markers.

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2012 Jun 1
The ‘normobaric oxygen paradox’: does it increase haemoglobin?
De Bels D, Theunissen S, Devriendt J, Germonpre P, Lafere P, Valsamis J, Snoeck T, Meeus P & Balestra C.

Background: A novel approach to increasing erythropoietin (EPO) using oxygen (O2) (the 'normobaric oxygen paradox') has been reported in healthy volunteers. We investigated whether the EPO increase is sufficient to induce erythropoiesis by comparing two protocols of O2 administration. Methods: We compared the effect of daily versus alternate days 100% O2, breathed for 30 minutes, on haemoglobin concentrations during a 12-day period. Nine subjects underwent the two protocols six weeks apart.

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2012 Jan 1
P-1359 - The impact of foot reexology on sleep induction in patients suering from sleeping disorders
Véron R, Balestra C, Berlémont C, Lanquart JP & Jurysta F.

Objective: The purpose of this study was to test the impact of foot reflexology (FR) on sleep architecture in patients suffering from sleeping disorders. Aims: Try to improve sleep quality in patients with sleep disorders using the foot reflexology.

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