[Study by radiolabelling of the residual time of a therapeutic gel in the nasal fossae]. / Etude par radiomarquage de la rémanence d'un gel thérapeutique dans les fosses nasales.

The residence times in the nose of the liquid and gel forms of the same therapeutic preparation were compared in 7 healthy subjects. A 50 microliters drop of the preparation, labelled with Tc99m, was placed down the head of the inferior turbinate, and the kinetics of its clearance from the site of deposition was monotired using a gamma camera, during 60 minutes for the liquid and 120 minutes for the gel. The average times for removal of 50% of the labelled material from the site of deposition were 10.3 minutes and 28.6 minutes for the liquid and gel forms respectively. The slower removal of the gel form is probably due to a mechanical effect, and seems to affect the whole nasal passage. The contact time between the preparation and the mucosa is increased in this galenic form and this should improve the efficiency of the preparation.

Discussion on smoke and mucociliary transport.

While the acute cilio-inhibitory action of tobacco smoke is no longer to be proved, the relative importance of the various components involved in such an effect still remains a subject for discussion. We have tried to determine the relative part played by the main compounds of the gaseous and particulate phases taking into account, on the one hand, the dilution factor occurring in the smoker during inhalation, and, on the other hand, the reversibility of the phenomena. Moreover, we have tried to specify the effect of the ciliary inhibition on the mucus rate of transport. Finally, among the possible mechanisms of action, we have examined the influence of the blockage of sulfhydryl groups in the cilio-inhibition induced by tobacco smoke.

[Prevention of gas microemboli during cardiac surgery. Numerical control of cardiac cavity purging by an ultrasonic detector]. / Prévention des micro-embolies gazeuses en chirurgie cardiaque. Contrôle numérique du débullage des cavités cardiaques par détecteur à ultra-sons.

Despite all precautions taken by cardiac surgeons to eliminate air remaining in the cardiac cavities and pulmonary veins at the end of cardiopulmonary bypass, many micro bubbles probably remain and pass into the systemic circulation with a risk of deteriorations of cerebral or myocardial function. Over the last four years we have used ultrasound to try to prevent the risk of preoperative gas microemboli: the machine is equipped with a detector (a quartz oscillator coupled to a piezoelectric transducer emitting a continuous beam of ultrasound at a frequency of 5 Mhz) which allows the following variables to be determined: the time interval from the onset of detection, the total quantity of bubbles (arbitrary units) in the examined regions, the quantity of bubbles detected over a given time interval which can be adjusted from 15 to 120 seconds. The passage of bubbles is also indicated by light and sound alarms. The smallest diameter of bubbles which can be detected is about 10 mu. There are periaortic probes adaptable to the calibre of the ascending aorta, transcutaneous probes for carotid artery detection and a left ventricular probe. In a preliminary series of 74 valve replacements in adults, this apparatus was used immediately after terminating cardiopulmonary bypass after we had thought that the cardiac cavities had been satisfactorily purged of air, and whilst active aspiration was continued in the ascending aorta distal to the periaortic probe: the total quantity of bubbles detected varied from less than 50 to more than 2000 AU, over a variable period of time which may exceed 20 min after termination of cardiopulmonary bypass. The total quantity of bubbles recorded after mitral valve (582 +/- 154 AU) or combined mitral and aortic valve replacement (685 +/- 167 AU) was generally greater than after isolated aortic valve replacement (335 +/- 126 AU). Therefore, after cardiopulmonary bypass, and despite all efforts at purging the air, we showed that numbers of microbubbles were ejected into the ascending aorta for a variable period of time: only some of them were eliminated by active aspiration through a trocar placed distal to the periaortic probe. The right coronary ostium was poorly protected against microbubbles because of its anatomical situation (6 cases in this series). We therefore established a protocol for the use of this apparatus to aid the purging of the cardiac cavities and pulmonary veins before stopping cardiopulmonary bypass: the manoeuvres, guided by the ultrasound probes, are performed before the left ventricle is allowed to eject blood into the ascending aorta.(ABSTRACT TRUNCATED AT 400 WORDS)

[Current status of objective measurements of nasal airflow]. / Etat actuel des mesures objectives de la ventilation nasale.

Objective quantitative measurements of nasal airway patency are badly known and used in clinical practice. However lot of difficulties may be overcame. The modern instruments have a good preciseness and the results are given with reproducibility. The authors sum up principal indications, wether medical or surgical, and insist on a necessary severe methodology.

[Diffusion and retention of therapeutical aerosols in upper airways (author's transl)]. / Diffusion et rétention des aérosols thérapeutiques dans les voies respiratoires supérierues.

The authors make a brief synthesis of the present data on the penetration and retention of therapeutical aerosols in upper airways. They analyze the mechanisms involved during the penetration of aerosols in the regions of the upper airways which are not swept by the inspiratory airflow, particularly in the accessory cavities of nasal fossa, sinus and Eustachian tube. Experimental results reveal that diffusion of aerosols can be improved at this level either by sound vibrations, or by combining vibrations to intermittent overpressures.

[A way of evaluating the tolerance of respiratory mucosa to thermal spring water (author's transl)]. / Une méthode d'évaluation de la tolérance de la muqueuse respiratoire aux eaux thermales.

The therapeutical solutions for respiratory mucosa such as some thermal spring water must be perfectly tolerated and it is presently accepted that one of the best criteria of tolerance is the maintenance of a normal ciliary function. The photo-oscillographic techniques developed by the authors enabled the measurement of the physiological frequency of ciliary beat in vitro, and of the effect, either stimulant or inhibiting, of the thermal spring water. The measurement is done either in liquid phase by immersion of a fragment of ciliated mucosa, or in gas phase by aerosolization. At the same time it is possible to control in man the effects of thermal spring aerosols on the mucocilliary drainage by a simple technique.

Effects on man of 30-day exposure to a PICO2 of 14 torr (2 %): application to exposure limits.

Pulmonary function, acid-base balance, renal electrolyte excretion, hematology, biorhythms and psychomotor test results were studied in six men during 30 days of exposure to a PICO2 of 14 torr (FICO2 = 0.02) with pre- and postexposure periods on air. Alveolar and arterial PCO2 increased and remained constant throughout the CO2 exposure (delta PACO2 = delta PACO2 = 2.5 torr); the rise in expiratory minute volume (delta VE = 60%) was related to the increased tidal volume. Oxygen uptake and carbon dioxide output increased about 10% because of the ventilatory work overload. Physiological dead space increased 8% without an alveolar-arterial PCO2 difference. Respiratory acidosis was mild (delta pH approximately or equal to 0.01) and the renal response was slight. There was no variation in plasma electrolytes, except a slight decrease in potassium. Red blood cell count decreased, showing a confinement effect. Adaptation to exercise was slightly impaired. Results of electrobiological and psychomotor tests and biorhythm evaluations showed no variation; application of these findings to CO2 exposure limits is discussed.

[Experimental results and use of the manosonic aerosoliser (U.D.V.) for the treatment of middle-ear and affections (author's transl)]. / Experimentelle Grundlagen und Anwendung eines Ultraschallverneblers mit Druckstoss und Vibration (UDV) für die Aerosolbehandlung der Nebenhöhlen und des Mittelohrs.

The Manosonic Aerosoliser (UDV in German) is an Ultrasonic generator delivering a dense aerosol in a closed inhalating circuit in combination with temporary overpressures and sonic vibrations. In order to evaluate the efficiency of this new mode of areosoltherapy the Authors devised a glass model: a small vessel representing a sinus was connected to the aerosol stream by a little tube, a small ball being applicated by its own weight on the aperture to simulate the pathological obstructions (dyspermeabilities). The aerosol was made from a solution of Lithium Choloride and the amount introduced estimated by atomic absorbiton spectrometry. An increase of about 15 fold was found between ordinary and vibrated(sonic) aerosols and 35 fold more between vibrated and U.D.V. A short summary of clinical results is given as a confirmation of the expected efficacity of the U.D.V. treatment.

[Mucociliary function and its alteration by certain irritants (author's transl)]. / La fonction muco-ciliaire et ses modifications sous l'influence de certaines agressions.

Mucociliary clearance is usually estimated in vivo by the measurement of mucus transfer or by clearance of radio-active tracers previously deposited in the airways. These methods are relatively difficult and complex so that for routine studies measures are usually made of ciliary activity. To clarify the consequences of changes in activity the authors have established the relationship between the speed of mucus transport and the frequency of ciliary beating. From their own studies and from evidence in the literature they show how the clearance function of mucociliary activity can be disturbed by a fall in temperature and humidity, by viral infection, by atmospheric pollutants such as sulphur dioxide, nitrogen dioxide and aldehydes and by tobacco smoking. They indicate the beneficial effects obtained by the administration of beta adrenergic compounds and the limits of efficiency of mucolytic agents. They examined the pathophysiological consequences of the slowing down or arrest of mucus drainage with particular reference to the proliferation of infectious agents and their penetration into respiratory mucus membranes.

[Effects of long term hypercapnia on plasma amino acids in the rat (author's transl)]. / Effets de l'hypercapnie prolongée sur les acides aminés du plasma chez le rat

Rats have been placed for periods from two hours to 22 days in a chamber, the atmosphere of which was enriched in CO2 (FICO2: 0.10). The acute phase of hypercapnia induces multidirectional changes of many plasma amino acids. Some of these changes lessen or become of an opposite direction during the first days of exposure; most of them disappear when the hypercapnic acidosis is partly compensated. The variety of these reactions seems due to the fact that CO2 brings into play various mechanisms of synthesis, circulation and catabolism.

[Kinetics of the compensation of respiratory acidosis induced by experimental chronic hypercapnia in man (author's transl)]. / Cinétique de la compensation de l'acidose respiratoire induite par l'hypercapnie chronique expérimentale chez l'homme

Four groups of male volunteers have been exposed in a tight climatical chamber to PICO2 of 14, 21, 28 and 32 torr; exposure periods varied from two to 30 days, between two reference periods in normal air. The results deal with the evolution of arterial blood acid-base equilibrium and that of renal response in relation to PICO2. In all exposures, the carbon dioxide alveolar overload increases by several torr during the first 24 hours on account of attenuation of the initial hyperventilation. Kinetics of the respiratory acidosis compensation differs according to hypercapnia which is moderate (PICO2 of 14 and 21 torr) or relatively severe (PICO2 of 28 and 32 torr). The decrease in arterial pH lessens as early as the 24th hour at PICO2 28 and 32 torr, and only after two days at PICO2 14 and 21 torr. The renal response is characterized by a significant increase in aciduria during the first 24 hours at PICO2 28 and 32 torr; the changes are smaller and start latter at PICO2 14 torr.

Persisting and unaltered circadian rhythms of six healthy young men with a night-work shift every 48 hrs and a 2% CO2 atmosphere during a 4-week span.

Six apparently healthy young males (20 +/- 0.5 years of age) lived in a specially designed laboratory for a 1-week span in normal air, followed by 4 weeks in a 2% CO2 atmosphere and thereafter 1 week again in normal air. Room temperature was 24 degrees C. +/- 1 degrees C.; relative hygrometry 75% +/- 5%. With respect to socio-ecologic time clues and cues, the subjects were not isolated. The subjects' social synchronization was altered only by the shift-work schedule (light-on, 07(00); light-off, 22(30) on normal days). Every other day each subject had a 3-h night task, located between 23(00) and 07(00). Once a week, during 48 hrs (Saturday and Sunday) a set of physiologic variables was documented every 4 hrs in order to study their circadian changes: oral temperature, peak expiratory flow, grip strength, arterial blood pressure, tempo, and urinary pH, volume and potassium excretion. As far as rhythms are detectable (cosinor method) the most striking result is that both rhythm acrophases and amplitudes do not show any statistically significant changes when comparing either night-work versus day-work and/or normal air versus air with 2% CO2. Both 3 hrs of night-work every other day and an unusual amount of CO2 do not alter the parameters characterizing the circadian rhythms considered. The absence of desynchronization during night-work could be related to: 1) the speed of rotation in the shift-work; 2) the short duration of night-work; and 3) the youth of the subjects.

[A micromethod for determination of nicotine and cotinine in blood and urine by gas chromatography. Results obtained from various smokers]. / Microméthode de détermination de la nicotine et de la cotinine dans le sang et l'urine par chromatographie en phase gazeuse. Résultats obtenus chez divers fumeurs

The determination of nicotine and cotinine in plasma and urines of smokers is carried out by gas-chromatography with an Ucon-Polar 50 HB 2000 alkalinized column and a specific N detector, using diphenylamine as internal standard. The technique for extraction and chromatographic analysis is developed. The limit values for a correct determination are : 0,2 ng for nicotine and 1 ng for cotinine. The results show that the transit of nicotine and cotinine into the blood is very fast. They confirm the rapidity of the urinary excretion of nicotine, the slowness of that of cotinine, and the relation between the eliminated amounts and the urinary flow.