Hyperoxia-induced alterations in cardiovascular function and autonomic control during return to normoxic breathing.

Hyperoxia causes hemodynamic alterations. We hypothesized that cardiovascular and autonomic control changes last beyond the end of hyperoxic period into normoxia. Ten healthy volunteers were randomized to breathe either medical air or 100% oxygen for 45 min in a double-blind study design.

Cardiac alterations induced by a fish-catching diving competition.

Cardiac changes induced by repeated breath-hold diving were investigated after a fish-catching diving competition. Eleven healthy subjects carried out repeated breath-hold dives at a mean maximal depth of 20 ± 2.7 msw (66 ± 9 fsw) during 5 h.

Pulmonary oedema in healthy SCUBA divers: new physiopathological pathways.

Introduction: The mechanism of immersion pulmonary oedema occurring in healthy divers is a matter of debate. Among consecutive injured divers admitted to our hyperbaric centre, we analysed prospective data about pulmonary oedema.

Method: A total of 22 divers suffering from immersion pulmonary oedema without cardiac disease were included.

A 5-month weight-reduction programme has a positive effect on body composition, aerobic fitness, and habitual physical activity of severely obese girls: a pilot evaluation study.

In this pilot study, we wished to determine whether a 5-month multidisciplinary programme of a combined dietary-nutritional education-exercise intervention would have favourable effects on the health status of 18 obese adolescent girls. Before and after the clinical intervention, body composition and habitual physical activity were assessed by bioelectrical impedance and accelerometry, respectively. Aerobic fitness and substrate utilization were determined by gas exchange using an incremental field test that mimics habitual conditions.

Combination of two oxidant stressors suppresses the oxidative stress and enhances the heat shock protein 27 response in healthy humans.

We tested the hypothesis that the combination of 2 oxidant stressors (hyperoxia and fatiguing exercise) might reduce or suppress the oxidative stress. We concomitantly measured the plasma concentration of heat shock proteins (Hsp) that protect the cells against the deleterious effects of reactive oxygen species. Healthy humans breathed pure oxygen under normobaric condition for 50-minute periods during which they stayed at rest or executed maximal static handgrip sustained until exhaustion.

Arterial compliance in divers exposed to repeated hyperoxia using rebreather equipment.

Background: Acute hyperoxic exposure is known to modify cardiovascular parameters like a decrease in cardiac output, arterial vasoconstriction, and autonomic nervous system changes. We hypothesized that repeated hyperbaric hyperoxic exposures, as experienced by military oxygen divers, lead to long-term arterial alterations.

Methods: Arterial blood pressure measurements and pulse wave velocity (PWV) recordings were performed during basal conditions in 15 elite military oxygen divers, and compared to 15 non-diver controls.

Haemodynamic changes after prolonged water immersion.

Thermoneutral water immersion increases cardiac preload and changes the neuroendocrine settings of blood volume regulation. The resulting marked diuresis may lead to significant haemodynamic changes after the end of a prolonged water immersion. Ten volunteers underwent 6 h of complete thermoneutral water immersion.

Fin swimming improves respiratory gas exchange.

Data in the literature suggest that compared to dry-land exercise fin swimming might delay the activation of the anaerobic metabolism. To verify this hypothesis, we explored indirect indices such as the oxygen pulse (VO(2)/HR), carbon dioxide production (VCO(2)), and ventilatory threshold, comparing fin swimming exercise to dry-land cycling. Thirteen participants, experienced or inexperienced in fin swimming, completed an incremental fin swimming exercise and a maximal exercise on a cycloergometer with breath-by-breath measurements of heart rate (HR), ventilation (VE), tidal volume (VT), VO(2), VCO(2), and VO(2)/HR and determination of the ventilatory threshold and maximal oxygen uptake (VO(2)max).

Military diving training improved arterial compliance.

This study was aimed at investigating whether repeated SCUBA diving might induce long term cardiovascular and autonomic modifications. In 11 military mine clearance diving students, arterial compliance (ultrasound scan study of brachial artery and ratio of stroke volume to pulse pressure: SV/PP), resting spectral analyses of heart rate and blood pressure variability, and a cold pressor test were performed before and after a 15-week military diving training course. After the diving training, arterial compliance was improved, as indicated by the significant increase in brachial arterial compliance (from 24+/-10 to 37+/-14 ml.

Diaphragmatic motion studied by m-mode ultrasonography: methods, reproducibility, and normal values.

Background: Although diaphragmatic motion is readily studied by ultrasonography, the procedure remains poorly codified. The aim of this prospective study was to determine the reference values for diaphragmatic motion as recorded by M-mode ultrasonography.

Methods: Two hundred ten healthy adult subjects (150 men, 60 women) were investigated.

Synthesis and evaluation of pyrazolo[3,4-b]pyridines and its structural analogues as TNF-alpha and IL-6 inhibitors.

In the present article, we have synthesized three different series of pyrazolo[3,4-b]pyridines and their structural analogues using novel synthetic strategy involving one-pot condensation of 5,6-dihydro-4H-pyran-3-carbaldehyde/2-formyl-3,4,6-tri-O-methyl-D-glucal/chromone-3-carbaldehyde with heteroaromatic amines. All synthesized compounds were evaluated for their anti-inflammatory activity against TNF-alpha and IL-6. Out of 28 compounds screened, 40, 51, 52 and 56 exhibited promising activity against IL-6 with 60-65% inhibition at 10 microM concentration.

Specific diving training-induced arterial circulation changes.

Objective: Several stressors such as cold water immersion, hyperoxic exposure and decompression-induced circulating bubbles can alter arterial circulation after a dive. The aim of this study was to investigate the arterial modifications induced by a specific diving training including repeated hyperbaric exposures and physical training.

Method: Arterial pressure measurement and pulse wave velocity (PWV) recordings were performed in 12 student military divers before and after 15 weeks' training.