• Ultrasound lung "comets" increase after breath-hold divingPeer reviewedClosed access 

      23 octobre 2010, LAMBRECHTS, Kate; GERMONPRÉ, Peter; Charbel, Brian; Cialoni, Danilo; Musimu, Patrick; Sponsiello, Nicola; Marroni, Alessandro; Pastouret, Fredéric; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      The purpose of the study was to analyze the ultrasound lung comets (ULCs) variation, which are a sign of extra-vascular lung water. Forty-two healthy individuals performed breath-hold diving in different conditions: dynamic surface apnea; deep variable-weight apnea and shallow, face immersed without effort (static maximal and non-maximal). The number of ULCs was evaluated by means of an ultrasound ...
    • The 'normobaric oxygen paradox': does it increase haemoglobin?Peer reviewedClosed access 

      14 juin 2012, De Bels, David; THEUNISSEN, Sigrid; Devriendt, Jacques; GERMONPRÉ, Peter; Lafère, Pierre; Valsamis, Joseph; SNOECK, Thyl; Meeus, Philippe; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      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 ...
    • Nitric oxide-related endothelial changes in breath-hold and scuba diversPeer reviewedClosed access 

      01 mars 2013, THEUNISSEN, Sigrid; Guerrero, François; Sponciello, Nicholas; Cialoni, Danilo; Pieri, Massimo; GERMONPRÉ, Peter; Obeid, Georges; Tillmans, Frauke; Papadopoulou, Virginie; HEMELRYCK, Walter; Marroni, Alessandro; De Bels, David; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      Objective: Scuba and breath-hold divers are compared to investigate whether endothelial response changes are similar despite different exposure(s) to hyperoxia. Design: 14 divers (nine scuba and five breath-holding) performed either one scuba dive (25m/25 minutes) or successive breath-hold dives at a depth of 20 meters, adding up to 25 minutes of immersion time in a diving pool. Flow-mediated ...
    • The effect of a passive stretch training protocol on performance during a drop jump in humansPeer reviewedClosed access 

      30 mars 2013, Levenez, Morgan; THEUNISSEN, Sigrid; Bottero, Antoine; SNOECK, Thyl; Tinlot, Arnaud; BALESTRA, Costantinoorcid-id; Provyn, Steven, HE Bruxelles Brabant
      Article scientifique
      Our study's aim is to show how a five-week stretch training protocol, based on passive stretching, can change muscle performance during a drop jump (stretch shortening cycle). METHODS: This study observes in 8 healthy subjects (four males and four females), the effect of a 5-week passive stretch training protocol on the stretch shortening cycle (SSC) during the performance of a drop jump, and identify ...
    • Effect of tetrahydrobiopterin and exercise training on endothelium-dependent vasorelaxation in SHRPeer reviewedClosed access 

      02 juin 2013, Guerrero, François; Sanéo, Thioub; Goanvec, Christelle; THEUNISSEN, Sigrid; Feray, Annie; BALESTRA, Costantinoorcid-id; Mansourati, Jacques, HE Bruxelles Brabant
      Article scientifique
      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 ...
    • Oxidative stress in breath-hold divers after repetitive divesPeer reviewedClosed access 

      08 juin 2013, THEUNISSEN, Sigrid; Sponciello, Nicholas; Rozloznik, Miroslav; GERMONPRÉ, Peter; Guerrero, François; Cialoni, Danilo; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      Introduction: Hyperoxia causes oxidative stress. Breath-hold diving is associated with transient hyperoxia followed by hypoxia and a build-up of carbon dioxide (CO₂), chest-wall compression and significant haemodynamic changes. This study analyses variations in plasma oxidative stress markers after a series of repetitive breath-hold dives. Methods: Thirteen breath-hold divers were asked to perform ...
    • The effect of a passive stretch training protocol on performance during a drop jump in humansPeer reviewedClosed access 

      15 juin 2013, Lévénez, Morgan; THEUNISSEN, Sigrid; Bottero, Antoine; SNOECK, Thyl; Bruyère, A; Tinlot, Arnaud; BALESTRA, Costantinoorcid-id; Provyn, Steven, HE Bruxelles Brabant
      Article scientifique
      Aim: Our study's aim is to show how a five-week stretch training protocol, based on passive stretching, can change muscle performance during a drop jump (stretch shortening cycle). Methods: This study observes in 8 healthy subjects (four males and four females), the effect of a 5-week passive stretch training protocol on the stretch shortening cycle (SSC) during the performance of a drop jump, ...
    • Effect of a single, open-sea, air scuba dive on human micro- and macrovascular functionPeer reviewedClosed access 

      15 août 2013, LAMBRECHTS, Kate; Pontier, Jean-Michel; BALESTRA, Costantinoorcid-id; Mazur, Aleksandra; Wang, Qiong; Buzzacott, Peter; Theron, Michaël; Mansourati, Jacques; Guerrero, François, HE Bruxelles Brabant
      Article scientifique
      Purpose: Previous studies have shown that bubble formation induced endothelial damage on conduit arteries. We aim to evaluate the effect of diving on microvascular and macrovascular function. Methods: Nine divers took part in a SCUBA dive at 30 msw (400 kPa), for 30 min of bottom time. Pre- and post-dive, they underwent an assessment of endothelial-dependent (acetylcholine) and endothelial-independent ...
    • Dark chocolate reduces endothelial dysfunction after successive breath-hold dives in cool waterPeer reviewedOpen access 

      16 septembre 2013, THEUNISSEN, Sigrid; Schumacker, Julie; Guerrero, François; Tillmans, Frauke; BOUTROS, Antoine; Lambrechts, Kate; Mazur, Alexandra; Pieri, Massimo; GERMONPRÉ, Peter; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      Objective: The aim of this study is to observe the effects of dark chocolate on endothelial function after a series of successive apnea dives in non-thermoneutral water. Methods: Twenty breath-hold divers were divided into two groups: a control group (8 males and 2 females) and a chocolate group (9 males and 1 female). The control group was asked to perform a series of dives to 20 m adding up to ...
    • Effect of oxygen-breathing during a decompression-stop on bubble-induced platelet activation after an open-sea air dive: oxygen-stop decompressionPeer reviewedClosed access 

      29 septembre 2013, Pontier, Jean-Michel; LAMBRECHTS, Kate, HE Bruxelles Brabant
      Article scientifique
      Purpose: We highlighted a relationship between decompression-induced bubble formation and platelet micro-particle (PMP) release after a scuba air-dive. It is known that decompression protocol using oxygen-stop accelerates the washout of nitrogen loaded in tissues. The aim was to study the effect of oxygen deco-stop on bubble formation and cell-derived MP release. Methods: Healthy experienced ...
    • Effect of decompression-induced bubble formation on highly trained divers microvascular functionPeer reviewedOpen access 

      07 novembre 2013, LAMBRECHTS, Kate; Pontier, Jean-Michel; Mazur, Aleksandra; Pontier, Jean-Michel; Buzzacott, Peter; Morin, Jean; Wang, Qiong; Theron, Michaël; Guerrero, François, HE Bruxelles Brabant
      Article scientifique
      We previously showed microvascular alteration of both endothelium-dependent and -independent reactivity after a single SCUBA dive. We aimed to study mechanisms involved in this postdive vascular dysfunction. Ten divers each completed three protocols: (1) a SCUBA dive at 400 kPa for 30 min; (2) a 41-min duration of seawater surface head immersed finning exercise to determine the effect of immersion ...
    • The "normobaric oxygen paradox": a new tool for the anesthetist?Peer reviewedOpen access 

      10 janvier 2014, Rocco, Monica; Ditri, Luciano; De Bels, David; Corazza, Francis; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      Hypoxia is the natural trigger for endogenous EPO production but recently the use of intermittent hyperoxia to stimulate EPO has been postulated and this phenomenon has been called the "normobaric oxygen paradox" (NOP). The "NOP" is a mechanism by which oxygen regulates the expression of the Hypoxia Inducible Factor 1 alpha (HIF-1alpha). The HIF-1alpha-depending gene regulation is responsible for ...
    • Effect of splenectomy on platelet activation and decompression sickness outcome in a rat model of decompressionPeer reviewedClosed access 

      01 septembre 2014, LAMBRECHTS, Kate; Pontier, Jean-Michel; Mazur, Aleksandra; Buzzacott, Peter; Goanvec, Christel; Wang, Qiong; Theron, Michaël; Belhomme, Marc; Guerrero, François, HE Bruxelles Brabant
      Article scientifique
      Introduction: Splenic platelets have been recognized to have a greater prothrombotic potential than others platelets. We studied whether platelets released by splenic contraction could influence the severity and outcome of decompression sickness (DCS) and bubble-induced platelet activation. Methods: Sixteen, male Sprague-Dawley rats were randomly assigned to either a control or a splenectomized ...
    • A ternary model of decompression sickness in ratsPeer reviewedClosed access 

      01 décembre 2014, Buzzacott, Peter; LAMBRECHTS, Kate; Mazur, Aleksandra; Wang, Qiong; Papadopoulou, Virginie; Theron, Michaël; BALESTRA, Costantinoorcid-id; Guerrero, François, HE Bruxelles Brabant
      Article scientifique
      Background: Decompression sickness (DCS) in rats is commonly modelled as a binary outcome. The present study aimed to develop a ternary model of predicting probability of DCS in rats, (as no-DCS, survivable-DCS or death), based upon the compression/decompression profile and physiological characteristics of each rat. Methods: A literature search identified dive profiles with outcomes no-DCS, ...
    • Relationships between plasma lipids, proteins, surface tension and post-dive bubblesPeer reviewedOpen access 

      13 février 2015, Schellart, Nico; Rozloznik, Miroslav; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      Decompression sickness (DCS) in divers is caused by bubbles of inert gas. When DCS occurs, most bubbles can be found in the venous circulation: venous gas emboli (VGE). Bubbles are thought to be stabilized by low molecular weight surfactant reducing the plasma-air surface tension (γ). Proteins may play a role as well. We studied the interrelations between these substances, γ and VGE, measured before ...
    • Relationships between plasma lipids, proteins, surface tension and post-dive bubblesPeer reviewedOpen access 

      13 février 2015, Schellaert, Nicolas; Rolzoznik, Miroslav; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      Decompression sickness (DCS) in divers is caused by bubbles of inert gas. When DCS occurs, most bubbles can be found in the venous circulation: venous gas emboli (VGE). Bubbles are thought to be stabilized by low molecular weight surfactant reducing the plasma-air surface tension (γ). Proteins may play a role as well. We studied the interrelations between these substances, γ and VGE, measured before ...
    • Pre-dive Whole-Body Vibration Better Reduces Decompression-Induced Vascular Gas Emboli than Oxygenation or a Combination of BothPeer reviewedOpen access 

      17 février 2015, Cavalade, Maxence; Papadopoulou, Virginie; THEUNISSEN, Sigrid; BALESTRA, Costantinoorcid-id, HE Bruxelles Brabant
      Article scientifique
      Purpose: The purpose of this study was (1) to further explore the heart rate dynamics and assess a potential cardiovascular risk in response to 4000 m jumps in experienced skydivers; (2) to assess whether there is an impact of such jumps on skydivers' cortical arousal or not, which may impact their decision making processes. Method: 18 experienced skydivers performed successive jumps from a plane ...
    • Influence of decompression sickness on vasocontraction of isolated rat vesselsPeer reviewedClosed access 

      18 février 2015, Mazur, Aleksandra; LAMBRECHTS, Kate; Wang, Qiong; Belhomme, Marc; Theron, Michaël; Buzzacott, Peter; Guerrero, François, HE Bruxelles Brabant
      Article scientifique
      Studies conducted in divers indicate that endothelium function is impaired following a dive even without decompression sickness (DCS). Our previous experiment conducted on rat isolated vessels showed no differences in endothelium-dependent vasodilation after a simulated dive even in the presence of DCS, while contractile response to phenylephrine was progressively impaired with increased decompression ...
    • The effect of pre-dive ingestion of dark chocolate on endothelial function after a scuba divePeer reviewedClosed access 

      15 mars 2015, THEUNISSEN, Sigrid; BALESTRA, Costantinoorcid-id; BOUTROS, Antoine; De Bels, David; Guerrero, François; GERMONPRÉ, Peter, HE Bruxelles Brabant
      Article scientifique
      Objective: The aim of the study was to observe the effects of dark chocolate on endothelial function after scuba diving. Methods: Forty-two male scuba divers were divided into two groups: a control (n=21) and a chocolate group (n=21). They performed a 33-metres deep scuba-air dive for 20 minutes in a diving pool (Nemo 33, Brussels). Water temperature was 33⁰C. The chocolate group ingested 30 g ...
    • Decompression induced bubble dynamics on ex vivo fat and muscle tissue surfaces with a new experimental set upPeer reviewedClosed access 

      04 avril 2015, Papadopoulou, Virginie; Evgenidis, Sotiris; Eckersley, Robert; Mesimeris, Thodoris; BALESTRA, Costantinoorcid-id; Kostoglou, Margaritis; Tang, Meng-Xing; Karapantsios, Thodoris, HE Bruxelles Brabant
      Article scientifique
      Vascular gas bubbles are routinely observed after scuba dives using ultrasound imaging, however the precise formation mechanism and site of these bubbles are still debated and growth from decompression in vivo has not been extensively studied, due in part to imaging difficulties. An experimental set-up was developed for optical recording of bubble growth and density on tissue surface area during ...