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Antoni Pons - One of the best experts on this subject based on the ideXlab platform.
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Scuba Diving induces nitric oxide synthesis and the expression of inflammatory and regulatory genes of the immune response in neutrophils
Physiological Genomics, 2014Co-Authors: Antoni Sureda, Juan M Batle, Josep A Tur, Xavier Capo, Miquel Martorell, Alfredo Cordova, Antoni PonsAbstract:Objective: Scuba Diving, characterized by hyperoxia and hyperbaria, could increase reactive oxygen species production which acts as signaling molecules to induce adaptation against oxidative stress...
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Scuba Diving induces nitric oxide synthesis and the expression of inflammatory and regulatory genes of the immune response in neutrophils
Physiological Genomics, 2014Co-Authors: Antoni Sureda, Juan M Batle, Josep A Tur, Xavier Capo, Miquel Martorell, Alfredo Cordova, Antoni PonsAbstract:Objective: Scuba Diving, characterized by hyperoxia and hyperbaria, could increase reactive oxygen species production which acts as signaling molecules to induce adaptation against oxidative stress. The aim was to study the effects of Scuba Diving immersion on neutrophil inflammatory response, the induction of oxidative damage, and the NO synthesis. Design: Nine male divers performed a dive at 50 m depth for a total time of 35 min. Blood samples were obtained at rest before the dive, after the dive, and 3 h after the Diving session. Measurements: Markers of oxidative and nitrosative damage, nitrite, and the gene expression of genes related with the synthesis of nitric oxide and lipid mediators, cytokine synthesis, and inflammation were determined in neutrophils. Results: The mRNA levels of genes related with the inflammatory and immune response of neutrophils, except TNF-α, myeloperoxidase, and toll-like receptor (TLR) 2, significantly increased after the recovery period respect to predive and postdive le...
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Scuba Diving activates vascular antioxidant system
International Journal of Sports Medicine, 2012Co-Authors: Antoni Sureda, Juan M Batle, Miguel D Ferrer, Antonia Mestrealfaro, Josep A Tur, Antoni PonsAbstract:The aim was to study the effects of Scuba Diving immersion on plasma antioxidant defenses, nitric oxide production, endothelin-1 and vascular endothelial growth factor levels. 9 male divers performed an immersion at 50 m depth for a total time of 35 min. Blood samples were obtained before Diving at rest, immediately after Diving, and 3 h after the Diving session. Leukocyte counts, plasma 8oxoHG, malondialdehyde and nitrite levels significantly increased after recovery. Activities of lactate dehydrogenase, creatine kinase, catalase and superoxide significantly increased immediately after Diving and these activities remained high after recovery. Plasma myeloperoxidase activity and protein levels and extracellular superoxide dismutase protein levels increased after 3 h. Endothelin-1 concentration significantly decreased after Diving and after recovery. Vascular endothelial growth factor concentration significantly increased after Diving when compared to pre-Diving values, returning to initial values after recovery. Scuba Diving at great depth activated the plasma antioxidant system against the oxidative stress induced by elevated pO 2 oxygen associated with hyperbaria. The decrease in endothelin-1 levels and the increase in nitric oxide synthesis could be factors that contribute to post-Diving vasodilation. Diving increases vascular endothelial growth factor plasma levels which can contribute to the stimulation of tissue resistance to Diving-derived oxidative damage.
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Scuba Diving increases erythrocyte and plasma antioxidant defenses and spares no without oxidative damage
Medicine and Science in Sports and Exercise, 2009Co-Authors: Antoni Sureda, Juan M Batle, Miguel D Ferrer, Josep A Tur, Pedro Tauler, Antoni PonsAbstract:Purpose: The aim of the present work was to study the effects of a single Scuba Diving immersion to high depth on erythrocyte and plasma antioxidant defenses, on erythrocyte cellular damage, and on nitric oxide (NO) production. Methods: Seven male preprofessional divers performed an immersion at a depth of 40 m for a total time of 25 min. Blood samples were obtained before the Diving session after overnight fasting, immediately after Diving, and 3 h after the Diving session was finished. Erythrocytes and plasma fractions were purified. Results: No significant differences were found in circulating erythrocytes, bilirubin, and hemoglobin concentration attributed to Diving. Hematocrit levels were reduced after Diving because of the reduction of erythrocyte size that was maintained after 3 h of recovery at the surface. Leukocyte counts significantly increased at recovery (38 +/- 4%). In erythrocytes, glutathione peroxidase activity significantly increased (18 +/- 4%) at recovery. A rise in plasma catalase activity (38 +/- 6%) immediately occurred after Diving, returning to basal values after recovery. Plasma superoxide dismutase activity significantly increased (58 +/- 7%) during recovery. Markers of oxidative damage in both erythrocytes and plasma such as malondialdehyde and protein carbonyl derivates remained unchanged after Diving. Nitrite levels significantly rose in plasma and erythrocytes (85 +/- 8% and 52 +/- 6%, respectively) at recovery. Conclusion: Scuba Diving session induced an antioxidant response in plasma and erythrocytes without the appearance of cellular damage and an increase in NO, which can be related with its vasodilator role.
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Scuba Diving enhances endogenous antioxidant defenses in lymphocytes and neutrophils
Free Radical Research, 2007Co-Authors: Miguel D Ferrer, Juan M Batle, Josep A Tur, Antoni Sureda, P Tauler, Antoni PonsAbstract:The aim was to study the effects of a Scuba Diving session on the lymphocyte antioxidant system, NO synthesis, the capability to produce reactive oxygen species and the antioxidant response in neutrophils. For that purpose seven male divers performed an immersion at a depth of 40 m for 25 min. The same parameters were measured after an hyperbaric oxygen (HBO) treatment at resting conditions in a hyperbaric chamber. Lymphocyte H2O2 production rose after Diving and after HBO treatment. Glutathione peroxidase (GPx) and catalase activities increased after Diving in lymphocytes, while after HBO exposure only increased GPx activity. Lymphocyte HO-1 mRNA expression increased after Diving and after HBO exposure, while iNOS levels and nitrite levels significantly increased after Diving. The hyperoxia associated to Scuba Diving leads to a condition of oxidative stress with increased lymphocyte H2O2 production, HO-1 expression, NO synthesis and antioxidant enzyme adaptations in order to avoid oxidative damage.
C Seiler - One of the best experts on this subject based on the ideXlab platform.
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recreational Scuba Diving patent foramen ovale and their associated risks
Swiss Medical Weekly, 2001Co-Authors: Markus Schwerzmann, C SeilerAbstract:In 1943 Emile Gagnon and Jacques Cousteau invented a self-contained underwater breathing apparatus (Scuba) with a demand valve, sensing the ambient pressure under water and automatically delivering the amount of air a diver needed at a particular depth. Since then, the popularity of Scuba Diving as a leisure time activity has been and still is rising. Today, the “Schweizer Unterwasser-SportVerband” has 12’000 active members, 150 Diving clubs and 55 Diving schools. Around 50’000 persons are Diving on a recreational basis annually in Switzerland, mostly using compressed air for breathing. Diving itself and the use of any high density Scuba Diving has become a popular leisure time activity with distinct risks to health owing to its physical characteristics. Knowledge of the behaviour of any mixture of breathable gases under increased ambient pressure is crucial for safe Diving and gives clues as to the pathopyhsiology of compression or decompression related disorders. Immersion in cold water augments cardiac preand afterload due to an increase of intrathoracic blood volume and peripheral vasoconstriction. In very rare cases, the vasoconstrictor response can lead to pulmonary oedema. Immersion of the face in cold water is associated with bradycardia mediated by increased vagal tone. In icy water, the bradycardia can be so pronounced, that syncope results. For recreational dives, compressed air (ie, 4 parts nitrogen and 1 part oxygen) is the preferred breathing gas. Its use is limited for Diving to 40 to 50 m, otherwise nitrogen narcosis (“rapture of the deep”) reduces a diver’s cognitive function and increases the risk of inadequate reactions. At depths of 60 to 70 m oxygen toxicity impairs respiration and at higher partial pressures also functioning of the central nervous system. The use of special nitrogen-oxygen mixtures (“nitrox”, 60% nitrogen and 40% oxygen as the typical example) decreases the probability of nitrogen narcosis and probably bubble formation, at the cost of increased risk of oxygen toxicity. Most of the health hazards during dives are consequences of changes in gas volume and formation of gas bubbles due to reduction of ambient pressure during a diver’s ascent. The term barotrauma encompasses disorders related to over expansion of gas filled body cavities (mainly the lung and the inner ear). Decompression sickness results from the growth of gas nuclei in predominantly fatty tissue. Arterial gas embolism describes the penetration of such gas bubbles into the systemic circulation, either due to pulmonary barotrauma, transpulmonary passage after massive bubble formation (“chokes”) or cardiac shunting. In recreational divers, neurological decompression events comprise 80% of reported cases of major decompression problems, most of the time due to pathological effects of intravascular bubbles. In divers with a history of major neurological decompression symptoms without evident cause, transoesophageal echocardiography must be performed to exclude a patent foramen ovale. If a cardiac right-to-left shunt is present, we advise divers with a history of severe decompression illness to stop Diving. If they refuse to do so, it is crucial that they change their Diving habits, minimising the amount of nitrogen load on the tissue. There is ongoing debate about the long term risk of Scuba Diving. Neuro-imaging studies revealed an increased frequency of ischaemic brain lesions in divers, which do not correlate well with subtle functional neurological deficits in experienced divers. In the light of the high prevalence of venous gas bubbles even after dives in shallow water and the presence of a cardiac right-to-left shunt in a quarter of the population (ie, patent foramen ovale), arterialisation of gas bubbles might be more frequent than usually presumed.
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recreational Scuba Diving patent foramen ovale and their associated risks
Swiss Medical Weekly, 2001Co-Authors: Markus Schwerzmann, C SeilerAbstract:Scuba Diving has become a popular leisure time activity with distinct risks to health owing to its physical characteristics. Knowledge of the behaviour of any mixture of breathable gases under increased ambient pressure is crucial for safe Diving and gives clues as to the pathophysiology of compression or decompression related disorders. Immersion in cold water augments cardiac pre- and afterload due to an increase of intrathoracic blood volume and peripheral vasoconstriction. In very rare cases, the vasoconstrictor response can lead to pulmonary oedema. Immersion of the face in cold water is associated with bradycardia mediated by increased vagal tone. In icy water, the bradycardia can be so pronounced, that syncope results. For recreational dives, compressed air (i.e., 4 parts nitrogen and 1 part oxygen) is the preferred breathing gas. Its use is limited for Diving to 40 to 50 m, otherwise nitrogen narcosis ("rapture of the deep") reduces a diver's cognitive function and increases the risk of inadequate reactions. At depths of 60 to 70 m oxygen toxicity impairs respiration and at higher partial pressures also functioning of the central nervous system. The use of special nitrogen-oxygen mixtures ("nitrox", 60% nitrogen and 40% oxygen as the typical example) decreases the probability of nitrogen narcosis and probably bubble formation, at the cost of increased risk of oxygen toxicity. Most of the health hazards during dives are consequences of changes in gas volume and formation of gas bubbles due to reduction of ambient pressure during a diver's ascent. The term barotrauma encompasses disorders related to over expansion of gas filled body cavities (mainly the lung and the inner ear). Decompression sickness results from the growth of gas nuclei in predominantly fatty tissue. Arterial gas embolism describes the penetration of such gas bubbles into the systemic circulation, either due to pulmonary barotrauma, transpulmonary passage after massive bubble formation ("chokes") or cardiac shunting. In recreational divers, neurological decompression events comprise 80% of reported cases of major decompression problems, most of the time due to pathological effects of intravascular bubbles. In divers with a history of major neurological decompression symptoms without evident cause, transoesophageal echocardiography must be performed to exclude a patent foramen ovale. If a cardiac right-to-left shunt is present, we advise divers with a history of severe decompression illness to stop Diving. If they refuse to do so, it is crucial that they change their Diving habits, minimising the amount of nitrogen load on the tissue. There is ongoing debate about the long term risk of Scuba Diving. Neuro-imaging studies revealed an increased frequency of ischaemic brain lesions in divers, which do not correlate well with subtle functional neurological deficits in experienced divers. In the light of the high prevalence of venous gas bubbles even after dives in shallow water and the presence of a cardiac right-to-left shunt in a quarter of the population (i.e., patent foramen ovale), arterialisation of gas bubbles might be more frequent than usually presumed.
Richard Castle - One of the best experts on this subject based on the ideXlab platform.
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can Scuba Diving offer therapeutic benefit to military veterans experiencing physical and psychological injuries as a result of combat a service evaluation of deptherapy uk
Disability and Rehabilitation, 2019Co-Authors: Alice Morgan, Harriet Sinclair, Alexander Tan, Ellen Thomas, Richard CastleAbstract:AbstractPurpose: To explore the effectiveness of Scuba Diving in providing therapeutic and rehabilitative benefit to ex-service personnel who have experienced traumatic physical and/or psychologica...
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can Scuba Diving offer therapeutic benefit to military veterans experiencing physical and psychological injuries as a result of combat a service evaluation of deptherapy uk
Disability and Rehabilitation, 2019Co-Authors: Alice Morgan, Harriet Sinclair, Ellen Thomas, Alexander Wei En Tan, Richard CastleAbstract:Purpose: To explore the effectiveness of Scuba Diving in providing therapeutic and rehabilitative benefit to ex-service personnel who have experienced traumatic physical and/or psychological injuries resulting from combat.Methods: This study took the form of a service evaluation of Deptherapy, a UK-based niche charity offering support to military veterans who have experienced life-changing injuries. Deptherapy provides Scuba Diving qualifications, consisting of theory and practical Diving experience, to participants alongside a Peer Support Buddy scheme that provides continuing support to servicemen involved with the charity. A total of 15 male veterans were invited to take part in the study. The methodology comprised retrospective and current quantitative measures of mental well-being and functional ability, utilising the General Health Questionnaire-28, and subsequent semi-structured interviews with participants, their families and health professionals.Results: Participants reported an improvement in levels of anxiety, depression and social functioning, and a reduction in insomnia, following their involvement in organised Scuba Diving activities. There was a mean average difference of 14.3 points improvement on the General Health Questionnaire-28 scale variants between prior interaction with Deptherapy and current perceptions following engagement with the programme. The positive perceptions, as indicated from the semi-structured interviews, were more pronounced in those whose injuries were predominantly psychological, rather than physical.Conclusion: Scuba Diving can offer significant therapeutic benefits, particularly for ex-military amputees experiencing co-morbid anxiety and/or chronic psychological adjustment disorders, notably in terms of improvements in social dysfunction and symptomology of depression.Implications for Rehabilitation Scuba Diving as a TherapyMilitary combat can result in devastating, chronic physical and/or psychological injury.Current research suggests that a combination of medical and psychological therapy may prove to be the most beneficial for military veterans.Scuba Diving has the potential to benefit injured veterans due the requirement of complete focus and the feeling of weightlessness when underwater.This article evaluates whether Scuba Diving is an effective physical and psychological therapy through GHQ-28 analysis and veteran interviews.Scuba Diving benefited injured veterans in terms of chronic pain relief and depression symptoms alleviation.
Antoni Sureda - One of the best experts on this subject based on the ideXlab platform.
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Scuba Diving induces nitric oxide synthesis and the expression of inflammatory and regulatory genes of the immune response in neutrophils
Physiological Genomics, 2014Co-Authors: Antoni Sureda, Juan M Batle, Josep A Tur, Xavier Capo, Miquel Martorell, Alfredo Cordova, Antoni PonsAbstract:Objective: Scuba Diving, characterized by hyperoxia and hyperbaria, could increase reactive oxygen species production which acts as signaling molecules to induce adaptation against oxidative stress...
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Scuba Diving induces nitric oxide synthesis and the expression of inflammatory and regulatory genes of the immune response in neutrophils
Physiological Genomics, 2014Co-Authors: Antoni Sureda, Juan M Batle, Josep A Tur, Xavier Capo, Miquel Martorell, Alfredo Cordova, Antoni PonsAbstract:Objective: Scuba Diving, characterized by hyperoxia and hyperbaria, could increase reactive oxygen species production which acts as signaling molecules to induce adaptation against oxidative stress. The aim was to study the effects of Scuba Diving immersion on neutrophil inflammatory response, the induction of oxidative damage, and the NO synthesis. Design: Nine male divers performed a dive at 50 m depth for a total time of 35 min. Blood samples were obtained at rest before the dive, after the dive, and 3 h after the Diving session. Measurements: Markers of oxidative and nitrosative damage, nitrite, and the gene expression of genes related with the synthesis of nitric oxide and lipid mediators, cytokine synthesis, and inflammation were determined in neutrophils. Results: The mRNA levels of genes related with the inflammatory and immune response of neutrophils, except TNF-α, myeloperoxidase, and toll-like receptor (TLR) 2, significantly increased after the recovery period respect to predive and postdive le...
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Scuba Diving activates vascular antioxidant system
International Journal of Sports Medicine, 2012Co-Authors: Antoni Sureda, Juan M Batle, Miguel D Ferrer, Antonia Mestrealfaro, Josep A Tur, Antoni PonsAbstract:The aim was to study the effects of Scuba Diving immersion on plasma antioxidant defenses, nitric oxide production, endothelin-1 and vascular endothelial growth factor levels. 9 male divers performed an immersion at 50 m depth for a total time of 35 min. Blood samples were obtained before Diving at rest, immediately after Diving, and 3 h after the Diving session. Leukocyte counts, plasma 8oxoHG, malondialdehyde and nitrite levels significantly increased after recovery. Activities of lactate dehydrogenase, creatine kinase, catalase and superoxide significantly increased immediately after Diving and these activities remained high after recovery. Plasma myeloperoxidase activity and protein levels and extracellular superoxide dismutase protein levels increased after 3 h. Endothelin-1 concentration significantly decreased after Diving and after recovery. Vascular endothelial growth factor concentration significantly increased after Diving when compared to pre-Diving values, returning to initial values after recovery. Scuba Diving at great depth activated the plasma antioxidant system against the oxidative stress induced by elevated pO 2 oxygen associated with hyperbaria. The decrease in endothelin-1 levels and the increase in nitric oxide synthesis could be factors that contribute to post-Diving vasodilation. Diving increases vascular endothelial growth factor plasma levels which can contribute to the stimulation of tissue resistance to Diving-derived oxidative damage.
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Scuba Diving increases erythrocyte and plasma antioxidant defenses and spares no without oxidative damage
Medicine and Science in Sports and Exercise, 2009Co-Authors: Antoni Sureda, Juan M Batle, Miguel D Ferrer, Josep A Tur, Pedro Tauler, Antoni PonsAbstract:Purpose: The aim of the present work was to study the effects of a single Scuba Diving immersion to high depth on erythrocyte and plasma antioxidant defenses, on erythrocyte cellular damage, and on nitric oxide (NO) production. Methods: Seven male preprofessional divers performed an immersion at a depth of 40 m for a total time of 25 min. Blood samples were obtained before the Diving session after overnight fasting, immediately after Diving, and 3 h after the Diving session was finished. Erythrocytes and plasma fractions were purified. Results: No significant differences were found in circulating erythrocytes, bilirubin, and hemoglobin concentration attributed to Diving. Hematocrit levels were reduced after Diving because of the reduction of erythrocyte size that was maintained after 3 h of recovery at the surface. Leukocyte counts significantly increased at recovery (38 +/- 4%). In erythrocytes, glutathione peroxidase activity significantly increased (18 +/- 4%) at recovery. A rise in plasma catalase activity (38 +/- 6%) immediately occurred after Diving, returning to basal values after recovery. Plasma superoxide dismutase activity significantly increased (58 +/- 7%) during recovery. Markers of oxidative damage in both erythrocytes and plasma such as malondialdehyde and protein carbonyl derivates remained unchanged after Diving. Nitrite levels significantly rose in plasma and erythrocytes (85 +/- 8% and 52 +/- 6%, respectively) at recovery. Conclusion: Scuba Diving session induced an antioxidant response in plasma and erythrocytes without the appearance of cellular damage and an increase in NO, which can be related with its vasodilator role.
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Scuba Diving enhances endogenous antioxidant defenses in lymphocytes and neutrophils
Free Radical Research, 2007Co-Authors: Miguel D Ferrer, Juan M Batle, Josep A Tur, Antoni Sureda, P Tauler, Antoni PonsAbstract:The aim was to study the effects of a Scuba Diving session on the lymphocyte antioxidant system, NO synthesis, the capability to produce reactive oxygen species and the antioxidant response in neutrophils. For that purpose seven male divers performed an immersion at a depth of 40 m for 25 min. The same parameters were measured after an hyperbaric oxygen (HBO) treatment at resting conditions in a hyperbaric chamber. Lymphocyte H2O2 production rose after Diving and after HBO treatment. Glutathione peroxidase (GPx) and catalase activities increased after Diving in lymphocytes, while after HBO exposure only increased GPx activity. Lymphocyte HO-1 mRNA expression increased after Diving and after HBO exposure, while iNOS levels and nitrite levels significantly increased after Diving. The hyperoxia associated to Scuba Diving leads to a condition of oxidative stress with increased lymphocyte H2O2 production, HO-1 expression, NO synthesis and antioxidant enzyme adaptations in order to avoid oxidative damage.
Zeljko Dujic - One of the best experts on this subject based on the ideXlab platform.
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high intensity cycling before Scuba Diving reduces post decompression microparticle production and neutrophil activation
European Journal of Applied Physiology, 2014Co-Authors: Dennis Madden, Marko Ljubkovic, Veena M Bhopale, Stephen R Thom, Ming Yang, Zeljko DujicAbstract:Venous gas emboli (VGE) have traditionally served as a marker for decompression stress after Scuba Diving and a reduction in bubble loads is a target for precondition procedures. However, VGE can be observed in large quantities with no negative clinical consequences. The effect of exercise before Diving on VGE has been evaluated with mixed results. Microparticle (MP) counts and sub-type expression serve as indicators of vascular inflammation and DCS in mice. The goal of the present study is to evaluate the effect of anaerobic cycling (AC) on VGE and MP following Scuba Diving. Ten male divers performed two dives to 18 m for 41 min, one dive (AC) was preceded by a repeated-Wingate cycling protocol; a control dive (CON) was completed without exercise. VGE were analyzed at 15, 40, 80, and 120 min post-Diving. Blood for MP analysis was collected before exercise (AC only), before Diving, 15 and 120 min after surfacing. VGE were significantly lower 15 min post-Diving in the AC group, with no difference in the remaining measurements. MPs were elevated by exercise and Diving, however, post-Diving elevations were attenuated in the AC dive. Some markers of neutrophil elevation (CD18, CD41) were increased in the CON compared to the AC dive. The repeated-Wingate protocol resulted in an attenuation of MP counts and sub-types that have been related to vascular injury and DCS-like symptoms in mice. Further studies are needed to determine if MPs represent a risk factor or marker for DCS in humans.
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acute and potentially persistent effects of Scuba Diving on the blood transcriptome of experienced divers
Physiological Genomics, 2013Co-Authors: Ingrid Eftedal, Marko Ljubkovic, Arnar Flatberg, Arve Jorgensen, Alf O Brubakk, Zeljko DujicAbstract:During Scuba Diving, the circulatory system is stressed by an elevated partial pressure of oxygen while the diver is submerged and by decompression-induced gas bubbles on ascent to the surface. This Diving-induced stress may trigger decompression illness, but the majority of dives are asymptomatic. In this study we have mapped divers' blood transcriptomes with the aim of identifying genes, biological pathways, and cell types perturbed by the physiological stress in asymptomatic Scuba Diving. Ten experienced divers abstained from Diving for >2 wk before performing a 3-day series of daily dives to 18 m depth for 47 min while breathing compressed air. Blood for microarray analysis was collected before and immediately after the first and last dives, and 10 matched nondivers provided controls for predive stationary transcriptomes. MetaCore GeneGo analysis of the predive samples identified stationary upregulation of genes associated with apoptosis, inflammation, and innate immune responses in the divers, most s...
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acute and potentially persistent effects of Scuba Diving on the blood transcriptome of experienced divers
Physiological Genomics, 2013Co-Authors: Ingrid Eftedal, Marko Ljubkovic, Arnar Flatberg, Arve Jorgensen, Alf O Brubakk, Zeljko DujicAbstract:During Scuba Diving, the circulatory system is stressed by an elevated partial pressure of oxygen while the diver is submerged and by decompression-induced gas bubbles on ascent to the surface. Thi...
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exercise after Scuba Diving increases the incidence of arterial gas embolism
Journal of Applied Physiology, 2013Co-Authors: Dennis Madden, Zeljko Dujic, Mislav Lozo, Marko LjubkovicAbstract:Arterialization of gas bubbles after decompression from Scuba Diving has traditionally been associated with pulmonary barotraumas or cardiac defects, such as the patent foramen ovale. Recent studies have demonstrated the right-to-left passage of bubbles through intrapulmonary arterial-venous anastamoses (IPAVA) that allow blood to bypass the pulmonary microcirculation. These passages open up during exercise, and the aim of this study is to see if exercise in a postDiving period increases the incidence of arterialization. After completing a dive to 18 m for 47 min, patent foramen ovale-negative subjects were monitored via transthoracic echocardiography, within 10 min after surfacing, for bubble score at rest. Subjects then completed an incremental cycle ergometry test to exhaustion under continuous transthoracic echocardiography observation. Exercise was suspended if arterialization was observed and resumed when the arterialization cleared. If arterialization was observed a second time, exercise was terminated, and oxygen was administered. Out of 23 subjects, 3 arterialized at rest, 12 arterialized with exercise, and 8 did not arterialize at all even during maximal exercise. The time for arterialization to clear with oxygen was significantly shorter than without. Exercise after Diving increased the incidence of arterialization from 13% at rest to 52%. This study shows that individuals are capable of arterializing through IPAVA, and that the intensity at which these open varies by individual. Basic activities associated with Scuba Diving, such as surface swimming or walking with heavy equipment, may be enough to allow the passage of venous gas emboli through IPAVA.
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determinants of arterial gas embolism after Scuba Diving
Journal of Applied Physiology, 2012Co-Authors: Marko Ljubkovic, Jaksa Zanchi, Toni Breskovic, Jasna Marinovic, Mihajlo Lojpur, Zeljko DujicAbstract:Scuba Diving is associated with breathing gas at increased pressure, which often leads to tissue gas supersaturation during ascent and the formation of venous gas emboli (VGE). VGE crossover to sys...
