Computerized single-breath nitrogen washout in children: variability and reproducibility.

The variability, short-term (1 hour) and long-term (2 weeks) reproducibility of the variables derived from the single-breath N2 test were evaluated in a group of 56 healthy children aged 10 to 16 years with a computerized system. The variability was low for vital capacity and total lung capacity (coefficient of variation less than 3%), moderate for residual volume and phase III N2 slope (9 and 13%) and very high for closing volume (more than 50%). A closing volume could not be identified by the computer algorithm in 18.3% of the trials. The reproducibility of the variables was satisfactory both at 1 hour and at 2 weeks, with the exception of the closing volume, whose increase at 2 weeks seemed to be due to methodological factors. We conclude that reliable results of static lung volumes and phase III N2 slope, but not of closing volume, may be obtained in children by a computerized system in epidemiological studies.

[The importance of nutrition among the risk factors in varicose veins]. / La place de l'alimentation parmi les facterus de risque des maladies veineuses.

The author reminds us that varicose veins involve a large social and financial cost. He states the the etiopathogenic hypotheses commonly suggested have not been confronted with geographic pathological data and that consequently they are of little value. A thorough study of the epidemiological data and clinical characteristics of the disease was made. The different factors which are considered or which are likely to be considered in the onset of varicose veins are investigated in light of these data. From this comparison, it appears that the Western diet is the fundamental cause of varicose inducement and that it leaves the other factors (predisposing, triggering or aggravating) as risk factors. The part it plays is probably due to a slight vitamin E deficiency which, once aggravated (during pregnancy for instance), would act upon venous walls, coagulation and fibrinolysis. Thus, the veins would become sensitive to blood stasis and to venous hypertension effects due in particular to constipation.

[Western diet: risk factors for varices and explanation of their different frequencies among French people and immigrants]. / L'alimentation occidentale: facteur de risque des varices et explication de la différence de leur fréquence entre français et immigrés.

Having run through the data of descriptive epidemiology, which shows a much lower incidence of varicose veins in certain countries of the Third World, the author examines the different aetiologies which are currently accepted or applicable and compares them with these data. He concludes that western alimentation is an important risk factor for varicose veins and that it probably acts through a lack of vitamin E. A preliminary survey, carried out in Lorraine among general practitioners who have both French and immigrant patients, shows a slight prevalence of varicose veins among recently arrived immigrants.

[Hydrogeology and medicine in the approach to health problems linked to nitrates: examples in Lorraine]. / Hydrogéologie et médecine dans l'approache des problèmes de santé liés aux nitrates: exemples en Lorraine.

An investigation carried out by French Ministration of Agriculture (S.R.A.E.L.) has worked out an inventory and defined the nitrate amount evolution in waters, specially originated with underground formations, stared out by collectivities. The investigation spreading has brought about some ascertainment in Lorraine country. Particularly, the "Laboratoire d'hygiène et de recherche en santé publique" has so identified in a commune near Nancy, where nitrate amounts in water are particularly high, gastrointestinal troubles probably caused by minor methemoglobinemias which water supply origin have not been locally suspected. This note so shows that medical and paramedical corps cooperation with administrative authorities charged with water resource can attempt some interventions: better diagnosis, population and mayors information, search of technical and administrative settlements according to local environment.