Publicaciones
Publicaciones científicas seleccionadas, sobre medicina y fisiología del buceo
Prevalence of acute respiratory symptoms in breath-hold divers
Cialoni D, Sponsiello N, Marabotti C, Marroni A, Pieri M, Maggiorelli F, Tonerini M, Frammartino B.

INTRODUCTION: After repetitive deep dives, breath-hold divers are often affected by a syndrome characterized by typical symptoms such as cough, sensation of chest constriction, blood-striated expectorate (hemoptysis) and, rarely, an overt acute pulmonary edema syndrome, often together with various degrees of dyspnea. The aim of this work is an epidemiological investigation to evaluate the prevalence of acute respiratory symptoms (ARS) in breath-hold divers (BHDs) in practicing breath-hold diving.

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2009 mar 3
Preventive effect of pre-dive hydration on bubble formation in divers
Gempp E, Blatteau JE, Pontier JM, Balestra C, Louge P.

OBJECTIVE: To investigate whether prehydration 90 min before a dive could decrease bubble formation, and to evaluate the consequent adjustments in plasma volume (PV), water balance and plasma surface tension (ST).

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2021 jun 30
Prolonged syncope with multifactorial pulmonary oedema related to dry apnoea training: Safety concerns in unsupervised dry static apnoea
Valdivia-Valdivia JM, Raisanen-Sokolowski A & Lindholm P.

Many competitive breath-hold divers use dry apnoea routines to improve their tolerance to hypoxia and hypercapnia, varying the amount of prior hyperventilation and lung volume. When hyperventilating and exhaling to residual volume prior to starting a breath-hold, hypoxia is reached quickly and without too much discomfort from respiratory drive. Cerebral hypoxia with loss of consciousness (LOC) can easily result. Here, we report on a case where an unsupervised diver used a nose clip that is thought to have interfered with his resumption of breathing after LOC. Consequently, he suffered an extended period of severe hypoxia, with poor ventilation and recovery.

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2005 mar 6
Pulpal and periodontal temperature rise during KTP laser use as a root planing complement in vitro
Nammour, Rocca JP, Keiani K, Balestra C, Snoeck T, Powell L, Reck JV.

The purpose of this study was to define the optimal irradiation conditions of a KTP laser during root planing treatment. METHODS: The surfaces of 60 single-root human teeth were scaled with conventional instruments before lasing. The pulpal temperature increase was measured by means of one thermocouple placed in the pulp chamber and a second one placed on the root surface at 1 mm from the irradiation site. The influence of variables of coloration by Acid Red 52 (photosensitizer), scanning speed, dentin thickness, and probe position was analyzed for a constant exposure time of 15 sec and 500 mw (spot size diameter, 0.5 mm). The pulpal temperature was below 3 degrees C for the adjustments.

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2012 dic 7
Pulsed high oxygen induces a hypoxic-like response in human umbilical endothelial cells and in humans
Cimino F, Balestra C, Germonpré P, De Bels D, Tillmans F, Saija A, Speciale A, Virgili F.

It has been proposed that relative changes of oxygen availability, rather than steady-state hypoxic or hyperoxic conditions, play an important role in hypoxia-inducible factor (HIF) transcriptional effects. According to this hypothesis describing the "normobaric oxygen paradox", normoxia following a hyperoxic event is sensed by tissues as an oxygen shortage, upregulating HIF-1 activity. With the aim of confirming, at cellular and at functional level, that normoxia following a hyperoxic event is "interpreted" as a hypoxic event, we report a combination of experiments addressing the effects of an intermittent increase of oxygen concentration on HIF-1 levels and the activity level of specific oxygen-modulated proteins in cultured human umbilical vein endothelial cells and the effects of hemoglobin levels after intermittent breathing of normobaric high (100%) and low (15%) oxygen in vivo in humans. Our experiments confirm that, during recovery after hyperoxia, an increase of HIF expression occurs in human umbilical vein endothelial cells, associated with an increase of matrix metalloproteinases activity. These data suggest that endothelial cells "interpret" the return to normoxia after hyperoxia as a hypoxic stimulus. At functional level, our data show that breathing both 15 and 100% oxygen 30 min every other day for a period of 10 days induces an increase of hemoglobin levels in humans. This effect was enhanced after the cessation of the oxygen breathing. These results indicate that a sudden decrease in tissue oxygen tension after hyperoxia may act as a trigger for erythropoietin synthesis, thus corroborating the hypothesis that "relative" hypoxia is a potent stimulator of HIF-mediated gene expressions.

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