684 - Validation Of Multi-frequency Bioelectrical Impedance Analysis In Detecting Changes In Fluid Balance Of Geriatric Patients.
OBJECTIVE:
Multi-Frequency Bioelectrical Impedance Analysis (MFBIA) is a quick, simple, and inexpensive method to assess body fluid compartments. This study aimed at determining the validity of MFBIA in detecting clinically relevant changes of fluid balance in geriatric patients.
DESIGN:
A prospective, observational study.
SETTINGS:
The 22-bed Geriatric Department of the University Hospital Nijmegen.
PARTICIPANTS:
Hospitalized patients were eligible if they did not have a pacemaker, were not suffering from terminal illnesses, and did not have psychogeriatric diseases likely to interfere with capacity to consent or comply. During a 16-months period, 218 patients were admitted, of whom 78 patients were eligible and 53 consented to participate.
MEASUREMENTS:
Each subject''s fluid balance was diagnosed twice a week as dehydrated, overhydrated, or euvolemic, based on standardized physical examination, laboratory tests, and weight evaluation. Changes in fluid balance were quantified by measuring total body water (TBW) and extracellular fluid (ECF) applying deuterium- and bromide-dilution techniques. Impedance at 1, 5, 50, and 100 kHz and body weight were measured daily. Sensitivity and Guyatt''s responsiveness indexes of MFBIA in detecting dehydration and overhydration were determined.
RESULTS:
In total, 1071 MFBIA measurements were performed, during which 14 transitions from dehydration to euvolemia and 13 transitions from overhydration to euvolemia were monitored. Rehydration of dehydrated patients caused an increase in TBW and ECF of 3.4 +/- 1.8 L and 1.9 +/- 1.9 L, respectively, which resulted in significant decreases in impedance of 133 +/- 67 omega at 1 kHz and 93 +/- 61 omega at 100 kHz (p = .001)
TREATMENT:
of overhydrated patients caused a TBW and ECF loss of 3.8 + /- 4.2 L and 3.1 +/- 3.8 L, respectively, which resulted in significant increases in impedance of 104 +/- 72 omega at 1 kHz and 81 +/- 68 omega at 100 kHz (p < .001). Sensitivity of a single MFBIA in diagnosing dehydration and overhydration was 14% and 17%, respectively. Responsiveness indexes of weighing and MFBIA for dehydration and overhydration were similar at all frequencies and greater than one.
CONCLUSIONS:
The sensitivity of a single impedance measurement in detecting dehydration and overhydration was low. However, responsiveness of serial measurements to intra-individual changes in fluid balance was good. Therefore, this noninvasive technique may be used in clinical practice to improve monitoring fluid balance in geriatric patients, especially when daily weighing is difficult.
Application de la technique de l'impédancemétrie multifréquence (4 fréquences) pour évaluer les compartiments hydriques : eau totale et eau extra-cellulaire chez des patients âgés hospitalisés évoluant de la déshydratation ou de la surhydratation vers la normohydratation.685 - Regulation Of Fluid Shifts.
Water is the largest single constituent of living organisms. The distribution and regulation of body water and electrolytes (principally the sodium and potassium ions) are vital importance to the adequate working of the main biological and physiological functions. The first part of this paper exposes some data concerning the distribution and the composition of body water compartments and the water exchanges between these compartments. The total body water content in men is usually taken as 60 % of total body weight (bw), and 50 % in women. Extracellular water is principally subdivised into interstitial water (approximately 16 % of bw) and plasma water (around 4,5 % of bw). Intracellular water corresponds approximately to 35 % of bw. The second part concerns the fluid exchanges between the internal and the external environments (intakes and outputs of water in adult) and the mechanisms involved in the regulation of these fluid exchanges (thirst and the control of water intake/ the hormonal system implied in the control of urinary water and electrolyte excretion).
Revue générale en langue française sur l'homéostasie des liquides corporels, et en particulier les réactions adaptatives aux perturbations de cet équilibre sous l'influence de l'exercice. Cette revue qui définit les compartiments liquidiens, les éléments du bilan hydrominéral (apports et sorties) et la régulation, peut être conseillée en lecture à tous ceux dont la connaissance du sujet est débutante.686 - Detection Of Hydration Status By Total Body Bioelectrical Impedance Analysis (bia) In Patients On Hemodialysis.
The purpose of the present study was to investigate whether total body bioelectrical impedance analysis (BIA) could be appropriate to assess normohydration (i.e. dry weight) in hemodialysis patients. This study is warranted, because the simultaneous assessment of both hydration and nutritional status by BIA requires the presence of a situation of normohydration in order to guarantee valid conclusions about the nutritional analysis. Segmental bioelectrical impedance was performed to classify patients according to their hydration status. BIA measurements revealed significant differences in TBW, ECW and ICW /ECW between three hydration subgroups (under-, normo, and overhydration), whereas ICW was similar. Therefore, TBW, ECW and ICW /ECW appear appropriate variables to assess hydration status in patients on hemodialysis. Hemodialysis diminished ECW significantly, whereas ICW did not change, suggesting that a decrease of ECW explains the fluid loss during hemodialysis.
Mesure des variations des différents compartiments hydriques par impédancemétrie au cours d'hémodialyse. Mise en évidence d'une diminution de la seule eau extracellulaire.687 - The Prediction Of Total Body Water And Extracellular Water From Bioelectric Impedance In Obese Children.
A study was conducted to assess the reliability of bioelectric impedance analysis (BIA) for predicting total body water (TBW) and extracellular water (ECW) in obese children. A comparison was carried out of 5 prediction models based on: body weight (Wt)/ the impedance (Z) index (ZI = height2/Z)/ the association of Wt and ZI/ the body surface area (SA) to impedance ratio SA/Z and the body volume (V) to impedance ratio V/Z Subjects were 30 obese and 25 control children 11.2 plus or minus 1.8 years old. TBW and ECW were assessed by deuterium and bromide dilution/ Z was measured at frequencies of 5, 50 and 100 kHz. In controls, Wt explained 11% more variance of TBW than ZI (r2 = 0.977, s.e.e. = 0.9 I, CV = 3.8%) and the association of Wt and ZI improved the prediction of TBW only slightly (r2 = 0.982, s.e.e. = 0.8 I, CV = 3.5%). The SA:Z and V/Z indexes explained 6 and 33% less variance of TBW, respectively as compared to Wt alone. In obese subjects, ZI explained 4% more variance of TBW than Wt (r2 = 0.914, SEE = 1.8 I, CV = 6.4%) and the SA/Z ratio was the most accurate predictor of TBW (r2 = 0.959, s.e.e. = 1.2 I, CV = 4.4%). However, the increase in the explained variance of TBW associated to the use of the SA/Z ratio was of only 1% as compared to the association of ZI and Wt. The V/Z ratio explained 9% less of variance of TBW as compared to ZI. In both control and obese subjects, the association of Wt and ZI offered the best prediction of ECW (r2 = 0.807, s.e.e. = 1.564 I and r2 = 0.826, s.e.e. = 1.035 I, respectively). However, the values of CV were much higher in controls than in obese children (17.5 vs. 8.4%) owing to their lower ECW and greater variability in ECW%. ZI was the most accurate predictor of TBW on the pooled sample (n = 55/ r2 = 0.910, SEE = 1.932 I, CV = 7.4%). However, it was a poor predictor of ECW on the same sample owing to its high CV (n = 55/ r2 = 0.866, s.e.e. = 1.806 I, CV = 17.0%). The body surface area to impedance ratio is the most accurate predictor of TBW in obese children but the association of ZI and Wt may be of more interest when BIA is used to estimate TBW and ECW. The impedance index offers a good prediction of TBW but not of ECW in children with different levels of fatness.
Evaluation de la validité des prédictions du contenu en eau totale par impédancemétrie chez des enfants normaux et obèses. L'étude souligne l'assez grande imprécision de la prédiction.688 - Practical Aspects Of Fluid Replacement.
This review combines the practical and scientific considerations required to develop a fluid and energy replacement plan, before, during and after exercise. The paper discusses the choices of beverages available, sport-specific tactics to facilitate optimal fluid replacement, environmental aspects contributions to fluid losses, methods of monitoring hydration levels, fluid replacement equipment and sports drinks regulations set by the Australia and New Zealand Food Authority. Tables are presented which describe the opportunities for fluid replacement in different sporting situations and different sources of carbohydrates during exercise.
Bonne revue générale sur les stratégies de réhydratation avant et après l'exercice. Les différents points abordés : hydratation pré-exercice, hyperhydratation, vidange gastrique, réhydratation après l'exercice, apport d'électrolytes, surtout Na+, restauration du glycogène hépatique, le sont clairement et sans difficulté de compréhension.689 - Rehydration Strategies Before And After Exercise.
This paper reviews issues of pre-exercise rehydration and post- exercise hydration and proposes fluid intake guidelines for athletes and those undertaking recreational exercise.
Revue de lecture aisée relative aux différents facteurs susceptibles d'interférer avec la biodisponibilité de l'eau bue : soif, palatabilité, vidange gastrique, concentration en hydrates de carbone et leur nature, volume ingéré, température de la boisson, boissons gazeuses, déshydratation, stress, exercice, adaptation climatique, absorption intestinale.690 - Dietary Sodium And Plasma Volume Levels With Exercise.
Sodium is the major cation of the extracellular fluid and has a potent influence on fluid movement. Sodium has been likened to a sponge that draws fluids into the extracellular space, including the plasma volume, to equalize gradients in concentration. Conventional wisdom suggests limiting dietary intake of Na+ to decrease risk of hypertension. However, there are some extreme occupational or exercise-related conditions where sweat losses are great and Na+ losses may exceed normal dietary intake. This can occur acutely such as in an ultra-endurance event or chronically as in hard manual work in the hear. In such cases, additional Na+ in the form of a higher Na + diet or adding Na+ to beverages used for fluid replacement may be warranted. A higher Na+ diet also appears to accelerate the cardiovascular and thermoregulatory adaptations that accompany heat acclimation or short term exercise training. Saline ingestion before exercise causes an expansion of plasma volume at rest and throughout the subsequent exercise bout. This expansion of plasma volume alters cardiovascular and thermoregulatory responses to exercise in ways that may lead to beneficial changes in endurance exercise performance. Plasma volume expansion also occurs with saline infusion during exercise, but exercise performance advantages have yet to be reported. The purpose of this article is to review the literature concerning dietary sodium and its influence on fluid balance, plasma volume and thermoregulation during exercise. It contains 2 major sections. First, we will discuss manipulations in daily Na+ intake initiated before or throughout an exercise regime. Second, we will examine studies where an acute Na+ load was administered immediately before or during an exercise trial. The dependent variables that we will discuss pertain to: (i) body water compartments, i.e. plasma volume/ (ii) thermoregulatory variables, i.e. core temperature and sweat rate/ (iii) cardiovascular variables, i.e. heart rate and stroke volume/ and (iv) performance, i.e. time trial performance and time to exhaustion. Particular attention will be given to the route by which Na+ was administered, the environmental conditions, the level of acclimation of the participants and specifics relating to Na + administration such as the osmolality of the Na(+)-containing beverage.
Cette revue consiste en une discussion touffue sur le rôle de l'ion Na+ dans l'homéostasie des compartiments liquidiens de l'organisme à l'exercice. En particulier, les auteurs développent les aspects liés à l'administration de sels de Na+ avant et après l'exercice. Très documentée, la discussion est complexe relativement exhaustive.691 - Potassium Changes In Trained Subjects After Potassium Loading And During Restriction Of Muscular Activity And Chronic Hyperhydration.
The hypothesis that urinary and plasma potassium changes developed during prolonged hypokinesia (HK) (decreased number of km run/day) in endurance-trained subjects could be minimized or reversed with a daily intake of fluid and salt supplementation (FSS) was examined in 30 endurance-trained men (23-26 years old) who ran ran an average of 13.8 km/day, prior to HK and had an average peak oxygen uptake of 65 ml /kg /min. Volunteers were randomly divided into 3 groups: 10 were restricted to an average of 2.7 km/day (unsupplemented hypokinetic subjects), 10 were restricted to an average of 2.7 km/day and were supplemented with sodium chloride 0.1 g/kg body weight and water 30 ml/kg body weight (supplemented hypokinetic subjects) and 10 control subjects whose training schedule and diets remained unaltered. During the pre-hypokinetic period of 60 days and during the hypokinetic period of 364 days, K loading tests were performed with potassium chloride 1.5-1.7 mEq/kg body weight and K, Na and chloride excretion in urine and plasma concentrations were estimated. In unsupplemented hypokinetic volunteers, urinary excretion of electrolytes and concentrations of electrolytes in plasma increased significantly compared with control and supplemented hypokinetic groups. It was concluded that daily intake of fluid and salt supplementation had a favourable effect on regulation of urinary and plasma K changes in trained subjects during prolonged HK.
Comme cela a déjà été noté par les mêmes auteurs en réalisant le même protocole chez les mêmes sujets (réf. 2997 et 3263) l'hyperhydratation chronique a un effet favorable sur la balance potassique de sujets entraînés soumis à une hypokinésie prolongée.692 - Enamel Fluoride Concentrations In Unerupted Third Molars And The Influence Of Fluoridated Water On Caries Scores.
Enamel fluoride concentrations in buccal and lingual surfaces were determined in successive layers obtained by the acid etch method. The 48 unerupted third molar teeth were from subjects who had lived continuously since birth in 2 Brazilian towns (Barretos and Riveirao Preto) with different fluoride levels in the drinking water but with similar socioeconomic conditions. The DMFT index was determined for children 7-12 years old living in the 2 towns. Enamel fluoride concentrations were significantly higher in teeth from the town with higher fluoride levels in drinking water. The children residing in the community with near-optimum fluoride concentration in the water had mean DMFT scores that were less than half those found in the community with a low level of fluoride in the drinking water.
Comparaison entre deux villes du Brésil, avec deux populations, qui diffèrent par l'apport en fluor dans l'eau mais qui sont pour le reste dans les mêmes conditions socio-économiques. L'étude concerne les enfants de 16 à 12 ans. On y trouve une meilleure répartition des index de l'état dentaire chez les enfants qui bénéficient d'une amélioration du taux de fluor dans l'eau par rapport aux autres. 693 - Fluoride Concentrations And Distribution In Premolars Of Children >From Low And Optimal Fluoride Areas.
Fluoride concentrations from the enamel surface were compared to the dentino-enamel junction (DEJ), and through dentine to the dentino-pulpal junction (DPJ) in premolars extracted from school children in Chemnitz (former Karl-Marx-Stadt), Germany (F: 1.0 mg/kg), Erfurt, Germany (F: 0.2) and Nagoya, Japan (F: 0.1 mg/kg in the water supply) . In teeth from children in Chemnitz, Erfurt and Nagoya, the profiles of F distribution using an abrasive microsampling technique revealed high F concentrations in the enamel surface, with a substantial decrease towards a plateau in the interior. In dentine the F concentrations were higher than in enamel, and also decreased to a plateau from the DEJ, thereafter increasing considerably towards the DPJ. F concentrations at any depth in the enamel and dentine of teeth from Chemnitz were 2-3 times higher than those in Erfurt and Nagoya. There was no significant difference in F concentrations or distributions between Erfurt and Nagoya. Close to the DEJ in both enamel and dentine as well as the enamel surface and the DPJ side of dentine, higher F concentrations were observed in Chemnitz compared with Erfurt and Nagoya.
On compare la concentration en fluor de l'émail et de la jonction entre l'émail et la dentine chez les prémolaires extraites des enfants en Allemagne, à Chemnitz, à Erfurt et aux enfants de Nagoya au Japon. Alors qu'il n'y a pas de différence significative dans la concentration en fluor entre ces pays, il y a des différences entre les zones dentino-émails et la surface de l'émail, qui sont plus hautes à Chemnitz qu'à Erfurt et Nagoya. 694 - Effects Of Caffeine And Noise On Mood, Performance And Cardiovascular Funct.
An experiment was conducted to examine the effects of caffeine and noise on mood, mental performance and cardiovascular function. One hundred and six young adults (mean age 21.2 years) took part in the study. Subjects were assigned to one of six groups formed by combining noise/quiet and drink (caffeinated coffee, decaffeinated coffee and fruit juice) conditions. Subjects were familiarized with the tasks and then completed a pre-drink baseline session (conducted in the quiet). Subjects were then given either caffeinated coffee (1.5 mg/kg caffeine), decaffeinated coffee or fruit juice. Following consumption of the drink subjects were re-tested 1 h later, either in noise (75 dBA conglomerate noise, consisting of speech, music and machinery noise) or in quiet. The subjects exposed to noise felt more anxious and showed an increase in blood pressure. Their performance of a cognitive vigilance task also declined over time. There were no significant main effects of caffeine, although simple reaction time was quickest in the caffeinated coffee group. Caffeine did not modify the effects of noise on mood, cardiovascular functioning or sustained attention. Indeed, the only interaction between drinks and noise was found in recall and recognition memory tasks, with the caffeine/noise group having better memory performance than the decaffeinated/noise subjects. Overall, the results show that low levels of caffeine do not increase the behavioural and physiological changes observed in a stressful situation.
Cette étude a été conduite pour examiner les effets de la caféine et du bruit sur les performances mentales et la fonction cardiovasculaire. 106 jeunes adultes ont été recrutés et répartis en 6 groupes par combinaison entre bruit / silence et type de boisson (café, décaféiné, et jus de fruits). Les sujets exposés au bruit étaient plus anxieux et montraient une augmentation de la pression artérielle. Leur performance sur un niveau de vigilance cognitive a décliné plus rapidement. Il n'y avait pas d'effet particulier de la caféine excepté le temps de réaction qui était légèrement plus court dans le groupe café. La caféine n' a pas modifié les effets du bruit sur les performances mentales, sur l'attention soutenue ni sur la fonction cardiovasculaire. La seule interaction entre boisson et bruit a été mise en évidence dans des tests de mémorisation où les sujets caféine + bruit avaient des meilleures performances que les sujets décaféine + bruit. Au total, ces résultats montrent que de faible niveau de caféine n'augmentent pas les capacités mentales et physiologiques des sujets dans des situations de stress.695 - Mechanism Of Attenuated Thirst In Aging: Role Of Central Volume Receptors.
To test the hypothesis that the inhibitory action of central blood volume expansion on thirst and renal fluid regulation is attenuated with aging, we monitored the drinking and renal responses of dehydrated older (70 +/- 2 yr, n = 6) and younger (24 +/- 1 yr, n = 6) subjects during 195 min of head-out water immersion (HOI), which shifts blood centrally and increases plasma volume (PV). Subjects dehydrated by exercising for 2 h at 36 degrees C in the evening and refraining from fluids overnight before HOI in 34 degrees C water or a seated control in water perfusion suit (time control (TC)) the next morning. Ad libitum water intake was allowed after 15 min of HOI. Dehydration decreased PV by 10.6 +/- 1 and 7.3 +/- 1.8% (p < 0.05) and increased plasma osmolality by 6 +/- 2 and 7 +/- 1 mosmol/kg H2O (p < 0.05) in older and younger subjects, respectively. Thirst ratings increased in both groups, but pre-HOI thirst perception on a line rating scale was lower in older (69 +/- 8 mm) than younger (94 + /- 6 mm, p < 0.05) subjects. Fifteen minutes of HOI restored PV by 7.8 +/- 1.0 and 5.7 +/- 1.0% in older and younger subjects, respectively, but suppressed thirst rating in younger subjects only (p < 0.05). Fluid intake was reduced in HOI compared with TC in younger (6.3 +/- 0.5 vs. 14.3 +/- 2.2 ml/kg, p < 0.05) but not in older (6.7 +/- 2.1 vs. 8.4 +/- 3.3 ml/kg) subjects. During HOI, older subjects had smaller suppression of plasma renin activity and aldosterone concentration but a greater increase in the plasma atrial natriuretic peptide concentration (P(ANP), p < 0.05). HOI increased fractional sodium excretion in both groups, but mean arterial pressure increased only in the older subjects (p < 0.05). We conclude that the inhibitory influence of central volume expansion on thirst and drinking behavior is diminished with aging. Furthermore, in contrast to younger people, HOI natriuresis is associated with exaggerated increases in P(ANP) and arterial blood pressure in older people, suggesting arterial baroreceptors may be involved in the fluid regulatory response to central blood volume expansion in older people.
Ce travail met pour la 1ère fois en évidence un possible hypofonctionnement des volorécepteurs périphériques (cardiaques) chez la personne âgée pouvant rendre compte des modifications de soif et de comportement dipsique observé. Les barorécepteurs artériels pourraient contribuer, chez la personne âgée, à la régulation de l'équilibre hydrominéral en cas d'expansion du volume sanguin.696 - A Comparison Of Three Fluid Replacement Strategies For Maintaining Euhydration During Prolonged Exercise.
The effectiveness of a new water delivery system (the Water-Del) was examined for maintaining euhydration compared to other fluid replacement strategies. Subjects (N = 10) performed three 60-min cycling trials (/50% of VO2max) in an environmental chamber (27 degrees C/ RH = 50%). Trials were randomly assigned from Water-Del (metered: 200 ml water every 15 min), ad libitum every 15 min (ad- lib-15), and ad libitum (ad-lib). Total water intake (TWI), changes in plasma volume (delta PV), body weight (delta BW), thirst, skin temperature (Tsk), and heart rate (HR) were measured. A significant difference (p &le/ .05) among trials was observed for TWI, with metered (1,200 +/- 0 ml) being greater than ad-lib-15 (358 +/- 48 ml) and ad-lib (522 +/- 106 ml). No significant difference was found for delta PV. A significant difference (p &le/ .05) for delta BW was observed with metered (0.28 +/- 0.16 kg) being different than ad- lib-15 (-0.63 +/- 0.12 kg) and ad-lib (-0.34 +/- 0.14 kg). No significant differences (p >.05) were found for thirst, Tsk, or HR. The water-Del provides for greater fluid intake during exercise compared to other replacement strategies.
L'ingestion volontaire ad libitum d'une boisson ne compense pas les pertes hydriques lors de la réalisation d'exercices physiques prolongés en ambiance chaude. La soif ne permet pas d'estimer les besoins réels en eau. Dans cette étude, la mise au point et l'utilisation d'un dispositif programmable de fourniture hydrique permet d'ingérer les quantités de liquides adaptées au besoin.697 - Vasopressin And Atrial Natriuretic Hormone Response To Hypertonic Saline During The Follicular And Luteal Phases Of The Menstrual Cycle.
We studied the hormonal responses to hypertonic saline during the follicular (days 2-9) and luteal (days 21-28) phases of the menstrual cycle in nine healthy young women, aged 19-25 years. On both study days, each woman was infused with 5% hypertonic saline for 1 h at the rate of 0.1 ml/kg/min. Serum progesterone and oestradiol concentrations confirmed the reported stage of the menstrual cycle. No difference in weight or haematocrit was observed between the two stages of the study for each woman. Baseline blood pressure, serum sodium, plasma osmolality, plasma vasopressin and thirst levels were almost identical for both stages, and changed to the same degree during infusion of hypertonic saline. Baseline atrial natriuretic hormone concentrations were higher during the follicular phase and became significantly higher than during the luteal phase following infusion of hypertonic saline. We concluded that the intravascular volume during the luteal phase may be effectively decreased in comparison to the follicular phase.
A conserver pour le principe, car sans grand intérêt scientifique.698 - Relationship Between Hydration Of Lean Body Mass And Visceral Adipose Tissue. A Clinical Study Of Women.
A study was conducted to examine the relationship between hydration of lean body mass and adipose tissue location. Visceral adipose tissue area and total body water as a percentage of lean body mass were evaluated. Subjects were 72 adult, overweight, women/ 52 pre- and 20 post-menopausal (age: 18-72 years, body mass index (BMI): 26-52 kg/m2). Total body water was obtained by electrical impedance measurement/ visceral adipose tissue and lean body mass were obtained by computed tomography measurement of visceral adipose tissue area at the level of the 4th-5th lumbar vertebra
RESULTS:
showed that visceral adipose tissue was found, by multiple regression analysis, to be the only predictor of the hydration of the lean body mass. The other independent variables: age, menopausal status, BMI, glucose and insulin both fasting and after glucose load were n able to significantly improve the predictive power. The results of this study confirm the existence of a relationship between visceral adipose tissue content and hydration of the lean body mass.
Etude à visée physiopathologique évaluant les relations (chez la femme obèse) entre adiposité et taux d'hydratation du compartiment maigre.699 - Comparison Of Bio-impedance Spectroscopy And Multi-frequency Bio- Impedance Analysis For The Assessment Of Extracellular And Total Body Water In Surgical Patients.
Estimations of extracellular and total body water provide useful information on the nutritional status of surgical patients and may be estimated from whole-body bio-impedance estimations at different frequencies. Resistance and reactance were estimated at 50 frequencies from 5 kHz to 1MHz in 29 surgical patients with a wide range of extracellular to total body water ratios. A fit to the spectrum of reactance versus resistance data gave predicted resistances at frequencies zero and infinity. Values of extracellular and total body water estimated by this bio-impedance spectroscopy technique were regressed against values obtained from radioisotope dilution. The standard errors of the estimate were 1.893 and 3.259 litres respectively. Resistance indices (height2/resistance) at selected frequencies gave the highest correlations with extracellular and total body water at 5 and 200 kHz respectively, and prediction equations derived from multiple stepwise regressions also showed these to be the optimum frequencies. The standard errors of the estimate for this multi-frequency bio-impedance analysis method were 1.937 and 2.606 litres for extracellular and total body water respectively. To assess the ability of the 2 methods to estimate changes in extracellular and total body water, reproducibility was assessed from repeat estimations 10 min apart in a subgroup of 15 patients. Bio-impedance spectroscopy gave mean coefficients of variation for extracellular and total body water of 0.9 and 3.0% respectively. For multi-frequency bio-impedance analysis the corresponding coefficients of variation were 0.9 and 0.6%. It is concluded that a simple impedance analyzer operating at only 2 frequencies compares favourably with the more complex spectroscopy technique for the estimation of extracellular and total body water in surgical patients.
Etude à visée technico-cognitive : apport de l'impédancemétrie multifréquence par rapport à la technique à seulement 2 fréquences pour la mesure de l'eau totale et de l'eau extracellulaire.700 - Body Fluids, Circadian Blood Pressure And Plasma Renin During Growth Hormon.
Side effects that can be related to fluid retention are common during the initial phases of growth hormone (GH) administration. The aim of this study was to examine the changes in body fluid compartments, diurnal blood pressure and plasma renin concentration during GH administration with two different dosages in healthy adults. Eight healthy male subjects aged 24-32 years were examined during three 2- week study periods in a double-blind placebo controlled study. They received, in random order, GH (3 or 6 IU m-2 daily) or placebo during 2 weeks. Bio-impedance was measured every 2nd day, and extracellular volume (ECV) and plasma volume (PV) were isotopically determined at day 6. Blood samples were obtained regularly. Diurnal blood pressure was recorded and 24-h urinary samples were collected at days 0, 6 and 14. ECV (l) was increased by GH (placebo, 19.58 +/- 0.82/ 3 IU m-2, 20.77 +/- 1.22/ 6 IU m-2, 20.65 +/- 0.94/ p<0.01), whereas PV (l) was unaffected (placebo, 3.91+/- 0.20/ 3 IU m-2, 4.04 +/- 0.22/ 6 IU m-2, 3.90 +/- 0.27). Total body water (l) increased significantly during GH administration (placebo, 50.8 +/- 2.6/ 3 IU m-2, 52.6 +/- 2.3/ 6 IU m-2, 53.9 +/- 1.8, p<0.05). After 6 days of treatment a significant increase in renin (p = 0.03) was observed. Mean diurnal blood pressure levels remained unchanged, whereas mean diurnal heart rate (/min) increased significantly (placebo, 75 +/- 3.6/ 3 IU m-2, 79 +/- 3.2/ 6 IU m-2, 79 +/- 3.7/ p<0.01)
IN CONCLUSION:
GH administration induces an elevation in total body water which may involve a stimulation of plasma renin and an increased ECV without any changes in PV or diurnal blood pressure.
L'effet sur l'hydratation de jeunes adultes de l'administration pendant 2 semaines d'hormone de croissance (GH) a été suivi par bio-impédance et par des isotopes. La GH entraîne une légère rétention d'eau du compartiment extra-cellulaire mais non sanguin. La pression artérielle reste inchangée malgré une légère élévation de la rénine plasmatique .701 - Multifrequency Bioelectrical Impedance Estimates The Distribution Of Body Water.
Bioelectrical impedance analysis was used to estimate the ratio of extracellular water (ECW) to total body water in 28 subjects with end-stage renal disease. The body''s resistance was estimated at frequencies ranging from 1 kHz to 1 MHz. Impedance index (height2 /resistance) estimated at low frequency (5 kHz) correlated most closely with ECW (r = 0.886) using sodium bromide solution as the standard of comparison. In contrast, the ratio of height squared to resistance estimated at high frequency (500 kHz) correlated most closely with total body water (r = 0.974) using deuterium oxide dilution as the standard of comparison. The ratio of resistance at 500 kHz to resistance at 5 kHz was directly correlated (r = 0.767) with the ratio of ECW to total body water. Multifrequency bioelectrical impedance analysis may assist in the evaluation of body water distribution in endstage renal disease and other clinical disorders of fluid volume and/or distribution.
Mots clés de cet article : physiopathologie / impédancemétrie multifréquence / compartiments hydriques / brome / pathologie rénale.702 - Validity Of Predicted Total Body Water And Extracellular Water Using Multifrequency Bioelectrical Impedance In An Ethiopian Population.
Total body water (TBW) and extracellular water (ECW) were estimated by deuterium oxide dilution and bromide dilution, respectively, in 24 male and 20 female healthy Ethiopians, living in Addis Ababa. Body weight, body height, skinfolds and total body impedance at 1 and at 100 kHz were also estimated. TBW and ECW were predicted from impedance values at 1 and 100 kHz, respectively, using prediction equations developed in a Dutch adult population. ECW was overestimated by 1.3 +/- 1.0 kg (p <0.05) and 0.6 +/- 0.8 kg (p <0.05) in males and females, respectively. TBW was accurately predicted in males (0.1+/- 1.9 kg, NS), but overestimated in females (1.0 +/- 1.3, p <0.05). TBW/height and ECW/height were substantially lower in the Ethiopians compared to values recently published in Dutch and Italian adults, indicating a different, more slender body build of Ethiopians. After correcting for these differences in body build and for slight differences in body water distribution (ECW/TBW), differences between estimated and predicted TBW and ECW decreased and were no longer significant
RESULTS:
indicate that the validity of predicted body water from impedance depends on the body build of the subjects, which should be taken into account to avoid systematic errors when applying prediction formulas from a reference population to another population under study.
Mesure des comportements hydriques par D2O et brome chez des Ethiopiens des deux sexes et comparaison avec les données de l'impédancemétrie bifréquence. Nécessité de corriger les équations de prédiction en tenant compte des caractéristiques des sujets.703 - Consumption Of Soft Drinks With Phosphoric Acid As A Risk Factor For The Development Of Hypocalcemia In Children: A Case-control Study.
A comparison of 57 cases (in children with serum calcium <2.2 mmol /litre) and 171 controls (children with serum Ca more than or equal to 2.2 mmol/litre) was carried out to assess whether the intake of at least 1.5 litre/week of soft drinks containing phosphoric acid is a risk factor for the development of hypocalcaemia. A significant association was found: odds ratio = 5.27/ 95% confidence interval 3.17 to 8.75/ p <0.001. The hypothesis of a causal relationship between intake of phosphoric acid-containing soft drinks and hypocalcaemia warrants further investigation.
1,5 litres de coca (en supposant = boissons contenant de l'acide phosphorique) sont associés avec une calcémie plus basse dans une étude cas/ contrôle chez des enfants. A confirmer dans une étude prospective.704 - The Effect Of Preoperative Oral Fluid Intake On The Volume And Ph Of Gastric Contents In Elective Surgical Patients - A Comparison Of Tea With Apple Juice.
This study aimed to investigate the effect of 150 ml of either tea or apple juice on the volume and pH of gastric contents in 40 elective surgical patients, ranging in age from 18 to 70 years. They were given diazepam 5 = 10 mg and roxatidine 75 mg orally 2 hours before the start of isoflurane anesthesia or modified neuroleptic anesthesia. Immediately following the induction of anesthesia with thiopental and vecuronium, a nasogastric tube was placed to aspirate the gastric content to measure its volume and pH. The volume and pH of gastric contents were 6.4 +/- 8.5 ml, 6.0 +/- 2.2 in tea group and 17.1+/- 18.4 ml, 4.4 +/- 2.6 in apple juice group, respectively. There was a significant difference in the gastric volume between the two groups (p <0.05), while no significant difference in gastric pH was observed. This result suggests that apple juice is not appropriate as preoperative drink because apple juice increases gastric contents, and may cause aspiration pneumonia.
Il semble préférable d'hydrater les patients subissant une anesthésie générale par du thé que par du jus de pomme car la vidange gastrique étant plus rapide avec le thé, le contenu gastrique est moindre au moment de l'induction anesthésique.705 - Improved Prediction Formula For Total Body Water Assessment In Obese Women.
A study was conducted to validate an improved formula for the calculation of total body water (TBW) from impedance values in obese women. Subjects were 37 overweight women (37.4 +/- 9.8 years old/ body mass index 29.5 to 44.1 kg/m2). The reference measurements to TBW were obtained by deuterium oxide dilution. Body height (h), hip circumference (C) as well as body impedance at 100 k Hz (Z100) were also measured. The values obtained for h, C and Z100 were introduced in the calculations and the following developed formula for total body water was estimated: TBW = 0.069 x (hC2/(4 pi x Z100)) + 19.671. The validity of this formula was assessed through the statistical test of Bland and Altman which we also performed for other formulae containing the weight and/or the height. It was found that the accuracy of the prediction of TBW by the formula developed, although lower than those formulae using body weight, was higher than that which takes into account only body height. It is concluded that body volume, expressed through body height and hip circumference, is a good choice of parameter in bioelectrical impedance measurements. The new approach can be useful in clinical settings for repeated monitoring of obese women, during diet-restricted treatment.
Etude à caractère fondamental avec développement d'une nouvelle formule pour déterminer le contenu en eau totale chez la femme obèse à partir de mesures par impédancemétrie.706 - The Use Of Bioelectrical Impedance Analysis To Predict Total Body Water In Patients With Cancer Cachexia.
The applicability of bioelectrical impedance analysis (BIA) to predict total body water (TBW) was assessed in 16 underweight (<95% of ideal body weight (IBW)) and 25 normal-weight (>95% of IBW) cancer patients. Although height2/resistance (ht2/R) proved to be a strong single predictor of TBW estimated by deuterium dilution in both groups (normal-weight patients: r2 =0.85, SEE 2.16 litre/ underweight patients: r2 = 0.86, SEE 2.24 litre), TBW would be significantly overestimated in the underweight group if the prediction formula developed in the normal-weight group was used (bias 1.67 litre (5%), 95% CI 0.20-3.15 litre). A systematic overestimation of TBW was predicted in the 2 patient groups by several previously published BIA formulas developed in normal-weight individuals. It is concluded therefore, that although a similar relation is found between ht2/R and TBW in normal-weight and underweight cancer patients, single- frequency BIA overestimates TBW in underweight patients when prediction formulas are used that have been developed in normal weight subjects.
Etude à visée physiopathologique évaluant la validité et les limites de la mesure de l'eau totale par impédancemétrie mono fréquence chez des patients cancéreux cachectiques. Mise en évidence d'une erreur systématique si utilisation des équations développées pour les sujets de poids normal.707 - Mechanisms Of Water Exchanges: The Starling Equation.
This review considers the main mathematical models used in the understanding of transvascular fluid exchanges and oedema formation. Models by Starling, Kedem-Katchalsky and Wiederhielm are briefly described. The main factors which determine the value of the physical parameters involved in these models are the osmotic and interstitial pressures in plasma and tissue. With regard to the regulation of interstitial osmotic pressure, the importance of the presence of mucopolysaccharidic gel in the interstitial compartment creating an exclusion volume for proteins diffusing from plasma is underlined, as well as the importance of lymphatic flow, a parameter neglected in several models of transcapillary exchanges. Consequences of variations in venous hydrostatic pressure, plasma oncotic pressure, endothelial permeability are discussed using the described models. In case of changes combining an increase in venous pressure and permeability and a decrease in plasma oncotic pressure, the importance of correcting venous pressure relatively to protein supply is discussed.
Il s'agit d'une revue relative à la modélisation mathématique des échanges transvasculaires et la formation des œdèmes. (Article très théorique de sciences fondamentales).708 - Deuterium Dilution As A Method For Determining Total Body Water: Effect Of Test Protocol And Sampling Time.
Deuterium dilution for the measurement of total body water (TBW) was conducted using varying protocols for equilibration. TBW was measured from deuterium dilution in urine samples in 28 subjects using 3 protocols: early morning dosage without breakfast, measuring deuterium in a second voiding at 4 and 6 h: early morning dosage with breakfast with the same measurement times/ and dosage at last consumption before overnight sleep, measuring deuterium in a second voiding at 10 h
RESULTS:
were compared with TBW estimates from underwater weighing (UWW). Because UWW is an indirect measure of TBW, it is used as an independent reference method in order to compare only relative discrepancies between the 2 methods. TBW values in the fasted state were not significantly different from those in the fed state. The urinary deuterium enrichment was higher at 4 than at 6 h (resulting TBW differences: 0.6 plus or minus 0.4 litre). At 4 and 6 h, differences in TBW measurements from deuterium and densitometry were positively related to the amount of TBW, indicating incomplete equilibrium in larger water compartments. At 10 h no such relation existed, indicating complete mixing of deuterium. It is concluded that 10 h equilibration is preferable to the shorter 4 and 6 h, for the estimation of TBW.
Article de méthodologie, exploration : Cet article évalue différents protocoles de mesure du contenu corporel en eau (eau totale) par la technique de dilution de l'eau deutérée comparée à l'hydrodensitométrie.709 - Multifrequency Bioelectrical Impedance As A Measure Of Differences In Body Water Distribution.
In 38 women, 21.3 +/- 1.8 years old, and 22 men, 21.6 +/- 2.0 years old, total body water (TBW) was assessed by bioelectrical impedance at a frequency of 100 kHz (Z100), and extracellular water (ECW) was assessed at a frequency of 1 (Z1) or 5 kHz (Z5). Impedance ratios of low frequencies (Z1 or Z5) to high frequency (Z100) were calculated as indicators of body water distribution. Furthermore, changes in body water distribution during the menstrual cycle were assessed in 16 women, 22.1 +/- 1.7 years old, divided into groups using or not using oral contraceptives. In general, the ratio ECW to TBW was lower in men, which was reflected in the ratios Z1/Z100 and Z5/Z100. However, the ratio Z5/Z100 reflected this difference less clearly, probably because at 5 kHz the current partly passes the cell membranes. Weight changes during the menstrual cycle are generally accepted to be due to a retention of ECW. The ratio Z5/Z100 and the ratios Z1/Z100 and Z5/Z100 for those women not using oral contraceptives differed significantly between day with minimal and day with maximal weight. A negative correlation was found between weight change, still considering day with minimal and day with maximal weight, and change in impedance at 5 and 50 kHz for women not using oral contraceptives. It is concluded that differences in body water distribution are reflected by low-to-high impedance ratios.
Article à visée physiopathologique, exploration et méthodologie : Etude par impédancemétrie à trois fréquences (1, 5 et 100 kHz) de la répartition extra et intracellulaire de l'eau corporelle chez des jeunes adultes des 2 sexes et en fonction du cycle ovarien. (Intérêt limité car cet article ne semble pas apporter d'éléments nouveaux).710 - Drinking Water With A Meal: A Simple Method Of Coping With Feelings Of Hunger, Satiety And Desire To Eat.
A study examining whether drinking water with breakfast affects feelings of satiety and hunger, and how long after the meal this effect is maintained is described. 8 healthy, normal-weight women (35.4 +/- 13.1 years old) had 3 breakfasts with 2 extra glasses of water (400 ml) and 3 similar breakfasts without water. The breakfasts were served on 3 successive mornings during 2 weeks. Subjects filled in forms with visual analogue scales on feelings of hunger, satiety and desire to eat. The forms were filled just before breakfast, in the middle of breakfast before and after drinking of water, after finishing the meal and thereafter every 30 min until 11.15
RESULTS:
showed that drinking 2 glasses of water affects subjective feelings of hunger and satiety during the meal, but this effect is not maintained after the meal. It is suggested that during a meal subjective feelings of hunger and satiety change independently of food energy consumed.
La surconsommation de 400 ml d'eau pure au cours d'un repas entraîne une plus grande réduction des paramètres psychophysiologiques en relation avec la prise alimentaire qu'au cours du repas contrôle sans surconsommation hydrique. Cependant, ce travail n'a pas comporté de mesures directes de la quantité d'aliments consommés.711 - Assessing Fluoride Concentrations Of Juices And Juice-flavored Drinks.
Few studies have investigated fluoride exposures from juices and juice-flavored drinks manufactured with water. In this study, the authors analyzed 532 juices and juice drinks for fluoride. Fluoride ion concentrations ranged from 0.02 to 2.80 parts per million, in part because of variations in fluoride concentrations of water used in production. Children''s ingestion of fluoride from juices and juice-flavored drinks can be substantial and a factor in the development of fluorosis.
Parmi les facteurs potentiels, expliquant l'augmentation de la fluorose chez les enfants et les adolescents. Cet article s'intéresse aux jus de fruit dont la concentration au fluor est parfois supérieure à 2,80 PPM. Ces concentrations peuvent être variables en fonction de l'eau qui est utilisée pour leur production.712 - Early Oral Hydration: A Novel Regimen For Management After Elective Cesarean Section.
OBJECTIVE:
To compare early oral hydration versus the conventional intravenous fluid replacement after elective cesarean section.
METHOD:
Two hundred women performed elective cesarean section were selected and randomized to: Regimen I (n = 100): early oral hydration (sips of fruit juices sweetened with honey once the women felt thirst immediately after the operation, then solid food 24 hours later, the amounts of juice or food were determined by the patient herself, i.e. she would regulate her physiological needs) versus regimen II (n = 100): conventional intravenous hydration (2-3 L of dextrose saline/24 hours and solid food thereafter). Biochemical, metabolic values, postoperative nausea and vomiting, propulsive bowel movements, tolerance of solid food, hospital stay and successful continuation of breast feeding were compared in both groups.
RESULTS:
The two regimens were equally effective in maintaining fluid balance and normal plasma and urinary electrolytes without any observed differences in biochemical or metabolic values. The return of bowel sounds, first occurrence of flatus and tolerance of solid food were achieved in regimen I at time periods significantly shorter than those attained with regimen II (p < 0.0001). The incidence of nausea and vomiting, ileus and deep vein thrombosis was higher in regimen II than in regimen I but the difference is statistically insignificant (p >0.05). Patients in regimen II were hospitalized for significantly longer times than those on regimen I (p < 0.0001). Successful continuation of breast feeding was significantly more in regimen I than in regimen II (p < 0.01).
CONCLUSIONS:
Early oral hydration after elective cesarean section effectively maintained fluid balance and it was associated with rapid return of propulsive bowel movements, successful breast feeding, less side effects and shorter hospital stay than the conventional intravenous hydration. So, it should be used in most cases after elective cesarean section.
Important même si l'étude souffre à l'évidence de quelques biais évidents.713 - Plasma Endothelin-1 Level In Athletes After Exercise In A Hot Environment: exercise-induced dehydration contributes to increases in plasma endothelin-1.
We investigated whether dehydration due to exercise contributes to the increase in plasma endothelin-1 (ET-1) concentration. We measured the plasma concentration of ET-1 before and after exercise in a hot environment (about 30 degrees C). Five male intercollegiate Kendo (Japanese fencing) players entered the present study. Each athlete participated in 15 min of Kendo fighting, followed by 5 min of rest and another 15 min of Kendo fighting (i.e., total exercise 30 min), with or without oral intake of 700 ml of water. Body weight and left atrial diameter, a parameter that reflects changes in circulating plasma volume, were significantly decreased after exercise under both conditions. However, the decreases in both values were significantly greater after exercise without water intake than after exercise with water intake, indicating that dehydration and decreased circulating plasma volume were more marked after exercise without water intake. The extent of the increase in plasma ET-1 concentration appeared to be closely related to the extent of exercise-induced dehydration/ the greater the dehydration, the greater the increase in plasma ET-1 concentration. These findings suggest that exercise-induced dehydration may contribute to increases in plasma ET-1 concentrations.
L'endothéline-1 a été mesurée à la fin d'un exercice de combat en ambiance chaude (30°C) chez de jeunes athlètes japonais, s'étant ou non réhydratés (700 ml d'eau). Les paramètres de deshydratation mesurés (dont un index du volume plasmatique) se modifient davantage chez les sujets n'ayant pas bu. L'accroissement de l'ET-1 observée est étroitement reliée à l'accroissement de la deshydratation. Les mécanismes et la signification de cette modification ne sont pas connus.714 - Infants'' Fluoride Ingestion From Water, Supplements And Dentifrice.
Concerns about dental fluorosis and the paucity of detailed fluoride intake data prompted this longitudinal study of fluoride intake in infants from birth to 9 months of age. On average, water fluoride intake greatly exceeded that from dietary fluoride supplements or fluoride dentifrice. However, fluoride supplements and dentifrice contributed substantial proportions of fluoride intake among children using them. Some children had estimated fluoride intake from water, supplements and dentifrice that exceeded the recommended optimal intake (a level that has yet to be determined scientifically). Practitioners should estimate fluoride ingestion from all these sources if considering systemic fluoride supplementation.
Il est nécessaire, pour les praticiens, d'être capable d'envisager toutes les sources possibles de l'apport de fluor avant de se décider à prescrire une supplémentation systématique.715 - Fluid Intake In Male And Female Runners During A 40-km Field Run In The Heat.
To compare physiological responses, hydration status and exercise performance in similarly trained men and women in a hot, humid environment, 12 highly trained runners were studied during a simulated 40-km race. A 7% carbohydrate-electrolyte (CE) beverage was consumed prior to exercise (400 ml) and every 5 km (approximately 250 ml) during the run. The run times of the males and females did not differ significantly (173.5 +/- 8.5 and 183.8 +/- 4.2 min, respectively)/ nor did the rate of fluid intake relative to body mass (10.3 +/- 0.7 and 10.7 +/- 0.8 ml /kg /h, respectively) or percent body mass loss (4.0 +/- 0.1% and 3.9 +/- 0.1%, respectively). During the run, %VO2 max, heart rate, concentrations of blood lactate, serum total protein and plasma osmolality were also similar for both groups. However, some significant sex differences (p < 0.05) were observed: the females had lower plasma volume losses and higher serum potassium and sodium concentrations than the males during the run. Rectal temperatures were lower in the female runners compared with the males during the last 10 km of the run (0.7 degrees C) and recovery (1.1 degrees C)
FINDINGS:
from this 40-km field run in hot, humid conditions suggest that CE fluid replacement at a relatively similar dosage (approximately 10 ml /kg /h) may have sex-specific physiological effects. These observations warrant further investigation to assess the need for sex-specific fluid replacement guidelines.
Les auteurs comparent les réponses en particulier thermiques et les variations hydroélectrolytiques entre athlètes hommes et femmes, au cours d'épreuves endurantes, en milieux chauds et humides, réalisées dans des conditions très similaires : durée et intensité, de l'exercice, volume et nature des boissons ingérées sont en effet identiques. Malgré cela, les athlètes femmes présentent moins de perturbations au niveau hydroélectrolytiques plasmatiques et au niveau thermique que les athlètes hommes. Les mécanismes qui seraient à l'origine de ces différences ne sont pas clairs et nécessiteraient des études complémentaires.716 - Antidiuretic Hormone Levels And Polyuria In Spinal Cord Injury: A Prelimina.
Chronic cervical spinal cord injury is characterized by defects in sodium and water homeostasis and defects of adaptive hormonal responses. The plasma osmolality is maintained in a relatively narrow range, the lower limit of which is determined by osmotic threshold for vasopressin release and the upper limit by the thirst threshold, antidiuretic hormone as an important mediator of fluid and electrolyte balance was well investigated in able bodied children comparing children with normal voiding pattern and children with enuresis. The normal subjects were found to have higher plasma ADH at night, not detected in the group with enuresis. The findings were similar in elderly patients with increased diuresis at night, suggesting an important role of ADH in nocturnal decrease of urine output. Investigators studied the effect of rapid tilt on plasma ADH in tetraplegic compared with normal subjects, but there are no data available in the literature regarding ADH and its effects on water and electrolyte balance in healthy tetraplegic subjects with a normal lifestyle. We decided to undertake a pilot study to attempt to establish baseline ADH levels in this subject group, to better understand and manage tetraplegic patients with water and electrolyte dysregulation. Our preliminary data suggest that these individuals lack the normal diurnal variation of ADH, a phenomenon similar to that demonstrated in enuretic children and elderly, and furthermore appear to have generally depressed ADH levels.
L'absence des taux cycliques chez les tétraplégiques expliquerait l'inversion de la diurèse chez eux. Un aplatissement de la courbe d'ADH est retrouvé chez les enfants énurésiques et chez les vieillards.717 - Predictive Value Of Tetrapolar Body Impedance Measurements For Hydration Status In Critically Ill Patients.
OBJECTIVE:
To design and evaluate a simple and rapid method to predict body hydration status in critically ill patients.
DESIGN:
Prospective, consecutive sample.
SETTINGS:
Medical intensive care unit of a university hospital.
PATIENTS:
31 consecutive patients.
METHOD:
All patients were classified daily for hydration status by the attending physician based on clinical impression, weight changes and laboratory measurements. The hydration status was scored as ''dehydrated'', ''euvolemic'' or ''edematous''. The total body impedance was measured daily by a tetrapolar impedance technique.
RESULTS:
Resistances >700 omega were found in dehydrated subjects and resistances of < 400 omega in edematous patients. Weight gain was observed in dehydrated and weight loss in edematous patients. A discriminant analysis was used to create a predictive model for hydration using the daily impedance and weight measurements. If a cutoff point of 60% for the predicted classification was used to categorize the patient''s hydration as dehydrated, euvolemic and edematous, no false positive predictions were observed for the dehydrated or the edematous state.
CONCLUSIONS:
Impedance measurements are in close agreement with the clinical impression of hydration of critically ill patients. Future investigations must elucidate the clinical importance.
L'impédancemétrie quadripolaire est aussi efficiente ( !!! ) pour classer des patients en service de soin intensif dans l'une des 3 catégories : déshydraté, euvolémique, oedématié.718 - Cd4+/cd8+ T-lymphocyte Ratio: Effects Of Rehydration Before Exercise In Dehydrated Men.
Effects of fluid ingestion on CD4+/CD8+ T-lymphocyte cell ratios were measured in four dehydrated men (ages 30-46 yr) before and after 70 min of supine submaximal (71% VO2max) lower extremity cycle exercise. Just before exercise, Evans blue dye was injected for measurement of plasma volume. The subjects then drank one of six fluid formulations (12 ml./kg) in 3-4 min. All six mean posthydration (pre-exercise) CD4+/CD8+ ratios (Becton-Dickinson Fluorescence Activated Cell Sorter and FACScan Consort-30 software program (San Jose, CA)) were below the normal range of 1.2-1.5/ mean (+/- SE) and range were 0.77 +/- 0.12 and 0.39-1.15, respectively. The post-exercise ratios increased: mean = 1.36 +/- 0.15 (p < 0.05) and range = 0.98-1.98. Regression of mean CD4+/CD8+ ratios on mean plasma osmolality resulted in pre- and post-exercise correlation coefficients of -0.76 (p < 0.10) and -0.92 (p < 0.01), respectively. The decreased pre-exercise ratios (after drinking) were probably not caused by the Evans blue dye but appeared to be associated more with the stress (osmotic) of dehydration. The increased post-exercise ratios to normal levels accompanied the rehydration and were not due to the varied electrolyte and osmotic concentrations of the ingested fluids or to the varied vascular volume shifts during exercise. Thus, the level of subject hydration and plasma osmolality may be factors involved in the mechanism of immune system modulation induced by exercise.
L'intérêt de ce travail est d'attirer l'attention sur le rôle que pourrait jouer la réhydratation préalable de sujets déshydratés soumis à un exercice musculaire prolongé, sur leurs réponses immunologiques.719 - Fluid And Electrolyte Losses During Tennis In The Heat.
A tennis player''s metabolism during play in a hot environment generates an abundance of heat, which is primarily eliminated from the body by evaporation of sweat. An individual''s on-court rate of fluid loss will depend on the environmental conditions, intensity of play, acclimatization, aerobic fitness, hydration status, age, and gender. Unless fluid intake closely matches sweat loss, a progressive and significant body water deficit may develop that will proportionately impair cardiovascular and thermoregulatory functions. As a result, a player can experience an increase in core temperature, premature fatigue, performance decrements, and an increased potential for heat illness. Although sweat is hypotonic compared to plasma, extended tennis play, in a hot environment, can lead to sizable Na+ and Cl- losses. Also, ad libitum drinking often leads to involuntary dehydration in these conditions. Therefore, for tennis play and training in the heat, it is important to follow a hydration plan that will minimize on-court water deficits, by optimizing fluid availability, consumption, and absorption. For tennis matches greater than 1 hour in duration, a CHO-electrolyte drink (as described earlier) is the recommended on-court beverage.
Revue intéressante sur les mouvements de l'eau, les pertes hydriques et le phénomène de "déshydratation volontaire" chez le joueur de tennis de compétition où le phénomène de soif et ceux liés aux différences sexuelles et à l'âge sont analysés.720 - Urinary Indices Of Hydration Status.
Athletes and researchers could benefit from a simple and universally accepted technique to determine whether humans are well-hydrated, euhydrated, or hypohydrated. Two laboratory studies (A, B) and one field study (C) were conducted to determine if urine color (Ucol) indicates hydration status accurately and to clarify the interchangeability of Ucol, urine osmolality (Uosm), and urine specific gravity (Usg) in research. Ucol, Uosm, and Usg were not significantly correlated with plasma osmolality, plasma sodium, or hematocrit. This suggested that these hematologic measurements are not as sensitive to mild hypohydration (between days) as the selected urinary indices are. When the data from A, B, and C were combined, Ucol was strongly correlated with Usg and Uosm. It was concluded that (a) Ucol may be used in athletic/industrial settings or field studies, where close estimates of Usg or Uosm are acceptable, but should not be utilized in laboratories where greater precision and accuracy are required, and (b) Uosm and Usg may be used interchangeably to determine hydration status.
Ce travail est réalisé dans le but de proposer une méthode simple, basée sur l'aspect des urines (volume, couleur, osmolalité, concentration en électrolytes, masse spécifique) dont l'acquisition est plus facile à mettre en œuvre sur le terrain qu'une prise de sang. Ces variables n'apparaissent pas corrélées significativement avec l'osmolalité ou la concentration sanguine en Na+, ou encore à l'hématocrite, en raison des mécanismes impliqués dans la préservation des constantes homéostatiques. L'osmolalité urinaire paraît être l'index le plus sensible et la couleur des urines est bien corrélée à l'osmolalité. Ces index peuvent donc être utilisés sur le terrain, après étalonnage, comme indices de l'état d'hydratation corporelle.721 - Fluorosis Due To Mineral Water Ingestion: Three Case Reports.
Three cases of bone fluorosis due to prolonged mineral water ingestion are reported. One patient was suffering from pelvic muscular weakness related to osteomalacia with skeletal condensation. Two others presented with lower extremity pain and diagnosis was made by bone scan showing typical stress fracture features.
Il concerne la fluorose liée à l'absorption de grandes quantités d'eau de Vichy. Les sujets traités pour lithiase uratique récidivante boivent 1,5 à 2 litres d'eau de Vichy durant des dizaines d'années. On constate des fluoroses osseuses par ostéo-condensation vertébrale, des ostéo-dystrophies des membres avec des taux sanguins de fluor très élevés. Ces lésions s'améliorent par l'arrêt de l'absorption des boissons.722 - The Maintenance Of Fluid Balance During Exercise.
Fluid supplementation is necessary for exercise in which fluid losses must be offset by intake to avoid the negative effects of hypohydration on health and performance. Several aspects of gastrointestinal function have been studied to gain information concerning the assimilation of ingested fluids to maintain fluid balance during exercise. Research results with regards to gastric emptying and secretion, intestinal absorption and secretion, and aspects of fluid retention, including urine production and plasma volume changes, can be utilised to formulate an appropriate fluid supplementation regimen. Increasing the volume of ingestate and decreasing the carbohydrate concentration promote gastric emptying of fluids. By maintaining a low osmolality secretion is reduced, thus leading to a greater rate of net fluid absorption. Adding sodium and carbohydrate (up to approximately 7%) increases the net intestinal absorption rate. Increasing carbohydrate concentration above this level begins to have a deleterious effect on intestinal absorption of fluid. Sodium also promotes retention of ingested fluids and leads to an increased plasma volume response during rehydration. The primary goal of supplementation should be considered, fluid vs carbohydrate provision, and the beverage composition altered accordingly. Beverage composition to maximise fluid provision will not maximise carbohydrate availability.
Revue relativement simple et bien documentée sur la fonction digestive (vidange gastrique et absorption intestinale) dans le processus d'absorption d'eau seule ou additionnée d'électrolytes et/ou de sucres. Sont analysés en particulier le rôle du volume d'ingestion, de la concentration en hydrates de carbone, de l'état, de la température de la boisson.723 - Detection Of Small Changes In Body Composition By Dual-energy X-ray Absorptiometry.
The ability of dual-energy x-ray absorptiometry (DEXA) to detect small changes in body composition was studied in 17 men and women during a dehydration-rehydration protocol. Scale weight (BW) and total mass (TM) from DEXA were highly related (r >0.99) as were estimates of fat-free mass (r = 0.99) and percent fat (r = 0.97) from DEXA and densitometry. Changes in BW of approximately 1.5 kg due to fluid loss and gain were highly correlated (r = 0.90) with both changes in TM and soft-tissue mass (STM) by DEXA but less so (r = 0.67) with changes in lean-tissue mass (LTM). Mean changes in TM, STM, and LTM were not different (p >0.05) from changes in BW. Estimates of bone mass and fat were unaffected by changes in hydration. We conclude that DEXA is able to detect small individual changes in TM and STM and is also useful for detecting group changes in LTM.
Application de la DEXA (absorptiométrie) à la mesure de petits changements dans la composition corporelle de sujets humains.724 - Disturbed Fluid And Electrolyte Homeostasis Following Dehydration In Elderly People.
Disturbances in homeostatic capacity are typical of the ageing process. Changes in the neuroendocrine controls of salt and water homeostasis with age make elderly people more susceptible to fluid and electrolyte disturbances such as dehydration and overhydration. Not only do elderly subjects show reduced thirst and water intake following dehydration, but their kidneys are less able to retain water. This reduced thirst and water intake is not dependent on palatability of the liquids offered as the amounts drunk are no different if water alone or a variety of beverages are offered to healthy elderly dehydrated men. It is of interest that the arginine vasopressin (AVP) response to dehydration is maintained in elderly subjects, indicating that their reduced renal water retentive capacity is due to relative renal resistance to vasopressin. The mechanism underlying the reduced thirst is unclear. Dehydration causes plasma hypertonicity and reduced extracellular fluid (ECF) volume, both of which stimulate thirst and AVP secretion. Elderly subjects show deficits in sensing the reduced ECF volume through reduced low and high pressure baroreceptor sensitivity. In contrast, while the AVP responses to hypertonicity are maintained, the thirst responses seem to be reduced. It seems unlikely that the primary sensing ''osmoreceptor'' neurons in the hypothalamus leading to AVP secretion or thirst would be differentially affected by age. Therefore the thirst deficit may result from changes with age in the more poorly defined pathways that bring thirst to consciousness. Following rehydration, thirst and AVP secretion are inhibited in young individuals thus avoiding overhydration.This occurs not only by replacing the water deficit but also more immediately via oropharyngeal sensors that inhibit thirst and AVP secretion immediately upon drinking before water is absorbed. These oropharyngeal sensors also seem changed by ageing as dehydration-induced AVP secretion is not inhibited as effectively by drinking in elderly as in young subjects. These changes in neuroendocrine homoeostatic mechanisms, as well as other renal changes with ageing, predispose even healthy elderly individuals to fluid and electrolyte disorders when excessive salt and water losses or exogenous intake (e.g. intravenous fluid administration) occur.
Petite revue à visée cognitive sur les mécanismes physiopathologiques rendant compte de l'hypohydratation de la personne âgée. Souligne en particulier le déficit de sensibilité des récepteurs vasculaires mesurant le volume des liquides extracellulaires.725 - Brick Tea Consumption As The Cause Of Dental Fluorosis Among Children From Mongol, Kazak And Yugu Populations In China.
Dietary fluoride intake and the prevalence of dental fluorosis were investigated in children from three population groups (mongol, Kazak and Yugu) in Gansu Province, China. The concentration of fluoride in drinking water ranged from 0.11 to 0.32 mg/litre/ there was no other fluoride pollution. There was a high prevalence of dental fluorosis-52, 84 and 76% among the Mongol, Kazak and Yugu children, respectively). Dental fluorosis was particularly severe among the Kazak population (severity index: 2.00, 3.05 and 2.57 among the three populations, respectively). Each of the population groups had a long tradition of drinking milk tea made from brick tea water. This milk tea was found to contain high concentrations of fluoride (2.58-3.69 mg/litre). The daily fluorine consumption was 1.36-2.42-times the US RDA of 2.5 mg for children. Regression analysis showed that fluorosis was significantly correlated with the consumption of milk tea made from brick tea water, but not with any other dietary component (including milk).
Dans les populations Mongol, Kazak et Ugu (province de Gansu, Chine), la fluorose dentaire est très importante mais il y a une longue tradition des buveurs de thé (brick tea), ainsi que du lait au thé, provenant de la même source (brick tea). La consommation par jour équivaut à 1,62 jusqu'à 2,42 fois supérieure aux recommandations US. La fluorose dentaire est particulièrement sévère chez les Kazak. Les analyses régressives montrent que la fluorose est corrélée significativement avec la consommation de thé au lait, fabriqué avec de l'eau de brick tea, mais pas avec les autres composants diététiques.726 - Magnesium And Calcium In Drinking Water And Cerebrovascular Mortality In Taiwan.
The relationship between death from cerebrovascular disease and the levels of magnesium and calcium in drinking water was examined using an ecological design. The study area consisted of 227 municipalities in Taiwan. Data on the levels of magnesium and calcium in drinking water have been collected from the Taiwan Water Supply Corporation (TWSC). These levels of magnesium and calcium were compared using the standardized mortality ratios (SMRs) for cerebrovascular disease (1981-1990). A statistically significant inverse relationship was present between cerebrovascular mortality and levels of both magnesium and calcium after adjusting for urbanization index. After adjustment for calcium levels in drinking water and urbanization index, the weighted multivariate-adjusted regression coefficient indicated a decrease of 0.248 in the standardized mortality ratios (SMRs) for every 100 mg/L increase in magnesium levels in drinking water. The results from this study strengthen the hypothesis that magnesium in drinking water helps to prevent death from cerebrovascular disease.
Les interrelations entre maladie cérébro-vasculaire et taux de Mg et de Ca dans l'eau de boisson ont été étudié dans 227 municipalités à Taiwan. Il existe, après ajustement par rapport à l'index d'urbanisation, une corrélation inverse statistiquement significative entre mortalité cardiovasculaire et les taux tant de Mg que de Ca. Après ajustement par rapport aux taux de Ca dans l'eau de boisson, le coefficient de régression multivarié indique une diminution des rapports de mortalité de 0.248 pour chaque augmentation de 100 mg/l du taux de Mg de l'eau. Les résultats de cette étude étayent l'hypothèse selon laquelle le Mg de l'eau de boisson aide à prévenir la mort par maladie cérébro-vasculaire.727 - Aluminum Concentrations In Drinking Water And Risk Of Alzheimer''s Disease.
To investigate the relation of aluminum and silicon in drinking water to risk of Alzheimer''s disease, we carried out a case-control study in eight regions of England and Wales. Subjects were identified from the records of neuroradiology centers, and diagnoses were confirmed by a review of hospital case-notes. Exposure to aluminum and silicon in drinking water was estimated from residential histories of 106 men with Alzheimer''s disease, 99 men with other dementing illnesses, 226 men with brain cancer, and 441 men with other diseases of the nervous system. All subjects in the study were between 42 and 75 years of age. There was little association between Alzheimer''s disease and higher aluminum or lower silicon concentrations in drinking water when cases were compared with any of the control groups. The results indicate that any risk of Alzheimer''s disease from aluminum in drinking water at concentrations below 0.2 mg per liter is small, and they give no support for a protective role of silicon.
Il s'agit d'une étude cas-témoins dans 8 régions d'Angleterre. Les sujets ont été identifiés d'après les registres des centres de neuroradiologie. L'exposition à l'aluminium et à la silice dans les eaux de boisson a été estimée d'après l'histoire des lieux de résidence pour 106 hommes avec la maladie d'Alzheimer, 99 hommes avec d'autres démences, 226 hommes présentant un cancer du cerveau et 441 avec d'autres maladies du système nerveux. Tous les sujets avaient entre 42 et 75 ans. Il n'a pas été trouvé d'augmentation du risque de maladie d'Alzheimer en fonction du taux d'aluminium dans l'eau ni de rôle protecteur de la silice. Le plan d'étude s'appuyant sur un cas-témoins n'est cependant pas complètement fiable, notamment le recueil de l'exposition basé sur un questionnaire postal. 728 - Analysis Of Adolescents'' Beliefs About The Outcome Of Using Dental Floss And Drinking Non-sugared Mineral Water.
Using an expectancy value approach, personal and normative beliefs about the outcome of using dental floss and drinking non-sugared mineral water were studied in a sample of 970 15-year-old adolescents in the county of Hordaland in Norway. The data stem from a survey performed in October 1992. A detailed analysis of these beliefs provides information about which of them should be targeted in a persuasive communication directed at changing behavior. The adolescents evaluated six outcomes of each behavior in terms of how much they wanted or feared them, and rated the probability of each outcomes happening. The adolescents also rated the probability that four significant referents would approve the performance of each behavior and how much they valued the approval of each referent. Subjects with relatively strong and relatively weak intentions to use dental floss and to drink non-sugared mineral water (intenders and non-intenders) were compared with respect to their scores on each measure. A one-way analysis of variance showed consistent differences between intenders and non-intenders. Intenders were more likely to believe that the specified behaviors would result in positive outcomes and they evaluated these outcomes as more desirable than non-intenders. Intenders believed their referens, in particular dentists and parents, to be more concerned about whether or not to perform the specified behaviors than non-intenders. The most promising candidates for persuasive communication among behavioral beliefs with respect to the specified behaviors appeared to be reduced tooth decay and several non, health beliefs in terms of immediate social and sensory concerns.
Une étude en 1992 en Norvège sur près de 1 000 adolescents de 15 ans présenterait un intérêt plus important pour les éducateurs de santé et les épiodémiologistes, sociologues et psychologues.729 - Caries Prevalence And Oral Hygiene In Lithuanian Children And Adolescents.
Contrary to what is observed in many Western societies, the caries prevalence among children and adolescents in the Baltic States remains high. The aims of the present study were to describe the caries prevalence and oral hygiene among 7-, 12-, and 15-year-old Lithuanians and to correlate the caries prevalence with fluoride content in the drinking water, oral hygiene, gender, ethnicity, and pattern of sugar consumption. The investigation was based on cluster samples, and the clinical investigation was performed in accordance with criteria defined by WHO. High DMFT values were registered (mean DMFT = 1.3 among 7-year-olds/ DMFT = 4.9 among 12-year-olds and 7.0 among 15-year-olds) and were associated with low fluoride content in the drinking water and poor oral hygiene. Girls showed higher DMFT values than boys. No correlation between pattern of sugar consumption and caries prevalence could be disclosed.
En Lituanie, la prévalence de la carie reste très élevée, comme dans les autres états baltes. Le faible taux de fluoration de l'eau et la mauvaise hygiène dentaire sont corrélés avec un taux de carie, surtout chez les filles entre 7, 12 et 15 ans.730 - Latent Fluorides: Report Of Case.
This case report examines the effects of a long-term exposure to fluoride on the teeth of two children who started to drink a highly fluoridated mineral water when they were three years and four years of age, respectively. A clinical and SEM study was conducted to supply evidence of the harmful effect of fluoride ingestion at above optimal levels and to ask for an explicit labeling of drinks that contain more than 1 ppm/F.
Etude sur l'effet à long terme d'un apport élevé en fluor par une eau minérale très riche, dont l'absorption a débuté précocement, avant l'âge de 3 ans. Les auteurs constatent des effets nocifs si la concentration est supérieure à 1 PPM de fluor. On ne donne pas d'indication sur le type d'eau minérale utilisée.731 - Concerning The Role Of Aluminum In Causing Dementia.
Topics outlined in an earlier paper by Eichhorn are expanded, with particular emphasis on the implications of the associations between aluminum (Al) concentrations and various indications of mental impairment. These associations represent the main thrust of the evidence that Al is a contributory cause for some forms of dementia. Of particular interest are the more recently observed associations between Al concentrations in drinking (finished) water and various indications of mental impairment, and the relevance of other water quality variables such as silica, fluoride, and pH. Various unresolved questions are also identified.
Revue plaidant en faveur d'une relation entre aluminium dans l'eau et maladie d'Alzheimer. 732 - An Introduction To Boron: History, Sources, Uses, And Chemistry.
Following a brief overview of the terrestrial distribution of boron in rocks, soil, and water, the history of the discovery, early utilization, and geologic origin of borate minerals is summarized. Modern uses of borate-mineral concentrates, borax, boric acid, and other refined products include glass, fiberglass, washing products, alloys and metals, fertilizers, wood treatments, insecticides, and microbiocides. The chemistry of boron is reviewed from the point of view of its possible health effects. It is concluded that boron probably is complexed with hydroxylated species in biologic systems, and that inhibition and stimulation of enzyme and coenzymes are pivotal in its mode of action.
Revue générale sur les sources de bore et la chimie du bore. Cet article rappelle que le bore, en dehors de la teneur des aliments en cet élément, se trouve également dans des produits d'utilisation courante tels que : le verre, la fibre de verre, les détergeants, les insecticides.733 - Health Effects Of Fluorine And Its Compounds.
Fluoride, the ionic form of fluorine, is a natural component of the biosphere and 13th most abundant element in the crust of the earth. It is, therefore, found in a wide range of concentrations in virtually all inanimate and living things. Many trace elements perform a definite function in human metabolism and the question of the value of fluoride, always found in the body, has been raised. Much evidence suggesting that the inclusion of fluoride in drinking water has beneficial as well as adverse effects on human health was obtained. Either alone or in combination with calcium and/or vitamin D, it is used in high daily doses for the treatment of osteoporosis. Although organic fluorine compounds are used in medicine and commerce, the inorganic fluorine compounds are of greater importance toxicologically because they are more readily available. The major pathway of fluoride elimination from the human body is via the kidney. When renal function deteriorates, the ability to excrete fluoride markedly decreases, possibly resulting in greater retention of fluoride in the body. At this point, more research is needed to evaluate the effects of physiological variables on the fluoride metabolism in humans.
Etude japonaise, considérant les effets du fluor, en général sur la santé et le métabolisme du fluor. C'est une étude physiologique sans intérêt évident pour le clinicien, qui est d'ailleurs très incomplète.734 - The Fluoride Content Of Bottled Drinking Waters.
Sales of bottled drinking waters in the United Kingdom have tripled over the last 5 years. The fluoride content of 12 bottled waters purchased from two Leeds supermarkets was determined by both the direct and acid diffusion methods and found to vary from 0.10-0.80 mg /l fluoride (ie ppm fluoride). This article shows that bottled drinking waters contain differing concentrations of fluoride. There is no apparent difference between the direct and acid diffusion methods for the determination of fluoride concentrations of drinking waters. The manufacturers'' labelling of fluoride concentrations are mainly inaccurate. Dentists should be aware of the fluoride concentrations of the drinking water of their child patients, be they municipal or bottled drinking water, when prescribing fluoride supplements. Also, some parents are using bottled waters to prepare baby milk formulations which themselves may contain high levels of fluoride and subject their children to the risk of dental fluorosis.
En Grande-Bretagne, il y a maintenant une grande mode d'absorption des eaux en bouteille, depuis une période de 4 ou 5 ans. Dans un supermarché de Leeds, on a répertorié 12 sortes de marques d'eau en bouteille. La concentration en fluor varie de 0,1 à 0,8 PPM. Néanmoins, le fabriquant donne des indications incertaines sur la plupart des bouteilles, en tout cas inappropriées pour que les parents puissent savoir quelle quantité ils donnent à leur enfant en reconstituant le lait par exemple. Ainsi, on ne peut pas apprécier le risque de fluorose dentaire.735 - Systemic Use Of Fluoride--other METHODS: Salt, Sugar, Milk, Etc.
An analysis of the literature evaluated the caries-protective effects of various methods of fluoridation. Salt fluoridation (250 or 350 mg F/kg) can be considered as equivalent to fluoridation of drinking water. Existing evidence suggests that milk fluoridation cannot be considered equivalent to fluoridation of either drinking water or salt because of problems of consistent delivery. Sugar, beverages (including tea), as well as fluoride-rich mineral waters are likely to be of only limited importance for caries prevention, but may be effective on an individual basis.
Analyse de la littérature sur l'apport en fluor : le sel fluoré à 250 ou 350 mg/kg est considéré comme équivalent à la fluorisation par l'eau de boisson. La quantité de fluor dans le lait est variable selon les saisons. L'apport par les sucres, les boissons, le thé et les eaux minérales, a une importance égale concernant la prévention des caries par le fluor.736 - Fluorine And The Dentition.
In order to estimate the influence of fluorine (in drinking-water and air) on the occlusion 372 twelve-year-old children have been examined in four different localities with differing fluorine concentrations of drinking water and air. Apart from the determination of the fluorosis frequency and of the DMFt index, the number of children who do not require any orthodontic treatment according to the WHO recommendation has been determined. The degree of malocclusion has been defined by means of the Eismann-Masztalerz''s method. There was observed that the optimal fluorine concentration in drinking water (0.7-0.9 mg/l) decreases the degree of malocclusion except for the crowding of the teeth whereas its concentration above the optimum (4.0-7.0 mg/l) as well as fluorine polluted air are one of the causes of crowding.
Les auteurs cherchent à connaître l'influence de la fluoration de l'eau et dans l'air, sur les anomalies de l'occlusion mandibulaire et les besoins de rééducation orthodontique ultérieurs. Le degré de mal occlusion est définie selon un score précis et on a constaté que le taux optimum de concentration en fluor dans l'eau (0,7 à 0,9 mg/l), fait diminuer le degré de mal occlusion.737 - Community Water Fluoride Levels, Preschool Dietary Patterns, And The Occurrence Of Fluoride Enamel Opacities.
Three hundred seventy-four 12- to 14-year-old children were examined to determine modified tooth surface index of fluorosis (TSIF) scores, and to assess the association among fluoride enamel opacities and water fluoride levels, preschool dietary patterns, and dentifrice consumption. The subjects included boys and girls of both black and white races who reported life-long residence in either Augusta or adjoining Richmond County. City children had communal water consistently fluoridated at levels of 0.9 to 1.2 ppm. County children had water variably fluoridated at levels of 0.2 to 0.9 ppm. TSIF scores were recorded on each included tooth and the highest TSIF tooth score was noted for each subject. The frequency of TSIF scores in all subjects was analyzed for dental arch symmetry and for association with city/county residence. The frequency of TSIF scores then was analyzed separately for city children and county children for an association with race, gender, preschool dietary habits, and dentifrice ingestion. Chi-square analysis revealed that higher TSIF scores were associated with city children significantly more than with county children. There was no association of TSIF scores either in the city children or the county children with respect to gender, race, preschool dietary patterns, or dentifrice ingestion. TSIF scores were bilaterally symmetrical, but were higher in the maxillary arch than in the mandibular arch.
Comparaison entre deux populations d'enfants pour l'index de fluorose : un groupe de ville et de campagne. Dans le groupe de ville, l'eau est fluorée à 0,9 à 1,2 PPM. Dans le groupe de campagne, l'eau est fluorée à 0,2 à 0,9 PPM. Il n'y a pas de différence sensible dans les deux populations.738 - Knowledge Of The Purpose Of Community Water Fluoridation--united States, 1990.
Expansion of water-fluoridation programs in the United States has been based on the clear documentation of the caries-preventive benefits of fluoride (1), as well as resources made available since the 1970s through the Fluoridation and Preventive Services Block grants administered by CDC. An estimated 135 million persons in the United States--approximately 61% of the population served by public water supplies--have access to drinking water with clinically important levels of fluoride (0.7 ppm or higher) for the prevention of dental caries (2). Efforts to expand the implementation of community water fluoridation require dissemination and understanding of information about health benefits and purported health risks. This report summarizes results from the 1990 National Health Interview Survey (NHIS) regarding public knowledge of the purpose and value of fluoridation of community drinking water.
A propos de la fluorisation de l'eau aux Etats-Unis / Environ 135 millions de personnes, soit 61 % de la population, reçoivent une eau fluorée à un taux moyen de 0,7 PPM. Ceci suffit notamment pour prévenir la carie dentaire mais il est nécessaire de répandre cette supplémentation dans les communautés, qui, pour le moment, ne l'ont pas reçu.739 - Fluoride Intake From Beverage Consumption In A Sample Of North Carolina Children.
Since the 1940''s, the prevalence of dental fluorosis has increased in the US, concomitant with a reduction in dental decay. These changes have been attributed in part to the widespread use of systemic and topical fluorides. Various sources of increased systemic fluoride exposure have been investigated. However, little is known regarding fluoride intake from beverages in a sample of children of ages susceptible to dental fluorosis. The purpose of this study was to estimate the amount of fluoride ingested from beverages by a sample of North Carolina (NC) children of ages 2-10 years. Data on beverage consumption were collected by means of a diary format. A questionnaire was included so that demographic information and self- assessment on the accuracy of the diaries could be obtained. Beverages reported in the diaries were purchased, and their fluoride content was assayed. Daily total fluid intake ranged from 970 to 1240 mL, and daily beverage consumption ranged from 585 to 756 mL. The estimated mean daily fluoride intakes from beverages for children 2-3, 4-6, and 7-10 years of age were 0.36, 0.54, and 0.60 mg, respectively.
En Caroline du Nord : La prévalence de la fluorose dentaire a beaucoup augmenté, comme dans le reste des États-Unis, avec parallèlement une réduction de la perte des dents. Ces modifications sont attribuées à l'administration de fluoride de plusieurs sources. Ce travail a donc tenté d'estimer la quantité de fluor ingérée chez des enfants de 2 à 10 ans. L'apport total de boissons se situe entre 970 et 1 240 ml de liquide par jour, sur lequel la consommation journalière de fluor varie de 0,36, 0,54 et 0,60 mg selon l'âge, 2 à 3, 4 à 6 ou 7 à 10 ans. 740 - Fluoride Levels And Fluoride Contamination Of Fruit Juices.
Increasing consumption of beverages as a replacement for water have made fluoride content in beverages an important issue. In this study, forty-three ready-to-drink fruit juices were examined for fluoride ion concentration. It was found that 42% of the samples had more than 1 ppm of fluoride. It was also determined that pure fruit juices, often grape juices, contained high levels of fluoride. Juice made from grapes separated from the skin did not contain any fluoride. Since it is common practice to use fluoride-containing insecticide in growing grapes, it is believed that contamination of these juices is occurring. Washing of grape skins produced appreciable quantities of fluoride. Given that increasing numbers of people are consuming beverages instead of water, fluoride supplementation should not be based solely upon the concentration of the drinking water, but should also consider the amount of different beverages consumed and their fluoride content.
On a étudié le taux de fluor dans 43 types de jus de fruits, utilisés par les enfants et les adolescents. Dans 42 % de ces jus de fruits, le taux de fluor était supérieur à 1 PPM. Ce taux très élevé était probablement lié au fait que les jus étaient préparés à partir de fruits non séparés de leur peau et peut-être là, y a-t-il intervention des pesticides. Il faut prendre en compte cet apport important en fluor pour calculer la couverture des besoins.741 - Fluoride Intake And Its Safety Among Heavy Tea Drinkers In A British Fluoridated City.
Tea-drinking in very young children has been studied in a British city. The results suggested that the fluoride in tea would, in some cases, be sufficient to influence caries. Clinical findings to some extent supported this. The main purpose of the investigation reported here was to determine maximum possible fluoride intake in adults who were heavy tea drinkers in a fluoridated city and relate it to toxic thresholds. Heavy tea drinkers were traced through Health Visitors and voluntary organizations and the volumes and fluoride concentrations of their drinks were measured. Even the highest intake found (9 mg) is below the probable intake in Bartlett, Texas (8 ppm of fluoride), in relation to which no undesirable symptoms have been reported (Leone et al. 1954). This confirms the safety of fluoridation. The effects on fluoride concentration of evaporating soft and hard fluoride-containing waters to small bulk were compared. The results showed ceilings of 3 ppm of fluoride in hard water and about 14 ppm in soft water, much higher than the levels expected on the basis of the usually stated solubility of CaF2 (16 or 8 ppm of fluoride). However, under normal household conditions, it is most unlikely that dangerous levels of fluoride would be ingested from boiled water.
En Grande-Bretagne, l'étude comparative des apports de fluor parmi la population des buveurs de thé. La crainte d'un excès d'apport de fluor, et donc d'augmenter la fluorose, ne s'est pas confirmée dans cette étude, même si les buveurs de thé utilisaient de l'eau déjà fluorée.742 - Fluoride Excretion In Schoolchildren With Differing Systemic Fluoride Care.
The aim of the present study was to collect data on urinary fluoride output in 8-16-year old students exposed to either drinking water fluoridation (DWF), or domestic salt fluoridation (DSF). Spot urine samples were collected in the canton of Basel-Stadt (DWF, n = 123), in the canton of Berne (DSF, n = 264), in the county of Davos (DSF, n = 241), and in the city of Winterthur (DSF, n = 40). Furthermore, fluoride concentrations were determined in plasma samples drawn from 33 students from Winterthur. The urinary fluoride concentrations were higher in Basel and Davos (0.62 +/- 0.35 mg/l/ 0.61 +/- 0.42 mg/l) than in Berne and Winterthur (0.46 +/- 0.42 mg/l/ 0.50 +/- 0.31 mg/l) . A relatively high natural fluoride content (0.3 mg/l) in the drinking water explained the difference in urine fluoride concentration between students from Davos and the two other regions with domestic salt fluoridation (Berne, Winterthur). The average fluoride concentration in plasma was 12.7 +/- 3.8 ng/ml. We concluded that, in general, the supply with fluoride consumed with fluoridated domestic salt is close to the level obtained with drinking water fluoridation. However, in areas with very low systemic fluoride supplementation through the drinking water this level might not be reached with salt as the only source of systemic fluoride. Also, the data confirmed the safety of domestic salt fluoridation.
En Suisse, pays de la fluoration par le sel, une étude comparative chez les étudiants des villes de Bâle, de Berne, de Davos et de Winterthur, concernant l'élimination de fluor urinaire. La concentration moyenne était de 12,7 ng/ml. L'apport par le sel domestique est proche de celui obtenu par l'apport hydrique. Dans les régions où l'eau est peu fluorée spontanément et non enrichie, l'apport par le sel domestique reste donc le meilleur système de prévention.743 - Fluoride Sources And Dental Attendance Habits Among Adults In Communities With Optimal And Low Water Fluoride Concentrations.
The aim of this study was to obtain data on local fluoride supply, dental attendance, and dental care habits in two sociologically similar municipalities with optimal, 1.0 ppm, and low, 0.3 ppm, water fluoride concentrations, respectively. The participants in the study were 30- to 40-year-old lifetime residents in the two municipalities: 569 individuals from the 1-ppm fluoride community and 466 from the low-fluoride community. There were no intergroup differences in the fluoride mouthrinse utilization rate of 1%. Fluoride toothpaste was much more common in the low-fluoride area. In the 1-ppm fluoride area more people drank tea, and they went more regularly to the dentist. It is suggested that dental attendance habits and various fluoride sources should be taken into account in studies evaluating the effect of fluoride in drinking water.
Etude sur la quantité de fluor apportée et ses conséquences sur l'état dentaire dans deux communautés : fluorée l'une à 0,3 et l'autre à 1 PPM/l. Lorsqu'on évalue le rôle de l'apport de fluor dans l'eau, il faut aussi tenir compte des autres sources de fluor.744 - Prevention Of Tooth Caries Using Mineral Water.
Numerous investigations showed that fluorides play an important role in the prevention of teeth caries, which acts as one of the most widely spread diseases nowdays. Consequently, the bringing in of optimal amounts of fluorides into an organism is of great value for the health of teeth. One of the possible sources of fluorides is mineral water, which brings out the importance of learning about the fluoride concentration in it. Fluoride determination was carried out by the potentiometric method, using the fluoride-selective electrode. Fourteen samples of mineral water from the common market in Novi Sad, were analysed. The results are given in mgF-/L and mumol F-/L. The fluoride concentration above 0.5 mgF-/L has the preventive effect on the health of teeth. From the obtained results it can be concluded that some mineral waters are recommendable as a source of fluorides needed to prevent teeth caries.
Parmi les facteurs qui améliorent la prévention de la carie dentaire et qui apportent la meilleure quantité de fluor dans l'organisme, il y a l'eau, notamment l'eau minérale. On a déterminé le taux de fluorure dans 14 types d'eaux minérales différentes, présentes sur le marché à Novi Sad. Le résultat a été donné en mg de fluor par litre, la concentration la plus basse qui est un effet préventif, est de 0,5 mg de fluor par litre. Il faut en conclure que les eaux minérales les plus recommandables sont celles qui sont proches de ce taux.745 - Water Fluoridation In The City Of Buenos Aires.
This paper tries to show benefits of artificial fluoridation of water supplies as a contributing factor to diminishing prevalence of dental caries. Data of fluoridation in Argentina and foreign countries are compilated. Arguments alleged in favor of water fluoridation in those water supplies with an insufficient natural level are quoted and adverse positions are refuted.
A Buenos Aires, Argentine, la fluoration artificielle des eaux de distribution est un facteur contributif pour diminuer la prévalence des caries dentaires. Dans cet article, on apporte des arguments allégués en faveur de la fluorisation lorsque le taux de naturel de fluor est insuffisant.746 - Fluoride Therapy Of Osteoporosis.
The effects of fluoride on bone seem to be dose- and time dependent: The optimized exposition to fluorides over decades might serve the bone as a trace element in a similar manner like in the case of caries prophylaxis of the teeth. This infers the potential that lifelong optimized fluoride supply (e.g. via drinking water) could serve as a general osteoporosis prophylaxis. This is to be differentiated from the use of much higher doses of fluoride as a pharmacological stimulus of the osteoblasts. In fact, such fluoride treatment increases the mass of trabecular bones, as demonstrated by histological and osteodensitometric techniques. In parallel during the last more than 20 years many retrospective studies yielded results indicating a decrease in osteoporotic fractures during fluoride treatment. However, the first two randomized double blind studies from the USA do not show this decrease in vertebral fracture incidence. The reasons for this could be due to the study design (unchanged high dosage over four years in contrast to the commonly used individual adaptation of dosage and time)/ however, also the earlier positive results could be an error. Therefore, new studies are mandatory, but until their results are available, the continuation of fluoride treatment of established osteoporosis is justified, competent surveillance being a prerequisite.
Etude des effets du fluor sur l'os et la dent. Depuis 20 ans, l'apport systématique de fluor a fait baisser considérablement le taux des fractures par ostéoporose. Ce phénomène n'est pas évident en ce qui concerne les vertèbres. Deux études randomisées aux Etats-Unis justifieraient la poursuite de telles études. En attendant, il est indispensable de continuer le traitement par le fluor lorsque l'ostéoporose est évidente.747 - A Comparison Of The Effects Of Different Concentrations Of Fluoride In The Drinking Water In Different Parts Of Port Elizabeth And Despatch: A First Report.
Since April 1993 a part of Port Elizabeth and the surrounding areas have been receiving water from the Orange river, containing on average 0.62 ppm fluoride, while the rest is still receiving water which contains < 0.1 ppm. During August 1994 a survey was done to determine whether the increased levels of fluoride in the Orange river water influenced the caries experience of school children using it. Schools in high, middle and low socio-economic areas in both areas were randomly identified and a random sample of 6-, 12- and 15- year-old children from these schools were examined for caries experience, using the 1987 WHO methodology and criteria for the diagnosis
RESULTS:
of the survey show that the caries experience in the permanent dentition of 12- and 15-year-old children respectively are 14.0 per cent and 7.8 per cent less in the areas receiving Orange river water, while in the primary dentition at age 6 it is 17.2 per cent higher. This study shows that after only 16 months the use of fluoride containing water may have benefited the permanent dentition of 12- and 15-year-old children. However the primary dentition of 6- year-old children showed a negative effect.
Etude en Afrique du Sud, portant sur les apports en fluor des eaux de rivière de la région de l'Orange et de Port Elisabeth. L'apport de l'eau de rivière est de 0,62 PPM de fluor. Une étude, en 1994, a consisté à augmenter l'apport pendant 16 mois à partir des eaux de rivière. Le résultat a été d'une efficacité certaine sur la dentition permanente des adolescents de 12 à 15 ans, mais pas d'effet sur la dentition des enfants de 6 ans.748 - Biochemical Effects Of Physiological Amounts Of Dietary Boron.
Research on human and animal boron nutrition has progressed sufficiently over the past decade to develop working hypotheses for biochemical roles of the element. It is well established that vascular plants, diatoms, and some species of marine algal flagellates have acquired an absolute requirement for boron although the primary role remains unknown. Discovery of naturally-occurring boron oxy compounds, all ionophoric macrodiolide antibiotics with a single boron atom critical for activity, established at least one biochemical role of boron. Recent findings suggest that physiological amounts of supplemental dietary boron (PSB) affect a wide range of metabolic parameters in chick and rat model systems as well as humans. Cholecalciferol (vitamin D3) regulates energy substrate utilization/ current findings indicate that boron modifies that regulatory function. For example, in chicks, PSB substantially corrected vitamin D3-deficiency-induced elevations in plasma glucose concentrations. Boron also alleviates perturbations in mineral metabolism characteristic of vitamin D3 deficiency. In rachitic chicks, PSB alleviated distortion of the marrow sprouts in the proximal tibia epiphysial plate. Boron may help prevent inflammatory disease as several key regulatory enzymes in the inflammatory response are inhibited by PSB. The findings to date support the hypothesis that boron is essential for animals and humans. Also, boron and vitamin D3 have the same overall effect on the utilization of energy substrates found in plasma. Further advances in boron nutrition research will probably include characterization of the mechanisms through which boron modulates immune function, insulin release, and vitamin D metabolism.
Le bore affecte de nombreux métabolismes comme cela est démontré dans des modèles expérimentaux et notamment le métabolisme osseux. La supplémentation par le bore corrige les effets d'une déficience en vitD3. Les recherches sur le bore doivent s'intensifier pour définir les mécanismes par lesquels le bore module la réponse inflammatoire, la sécrétion d'insuline et lme métabolisme de la vit D.749 - Fluoride Controlled Release Systems In The Prevention Of Dental Caries.
Research on drug controlled release devices indicate, in particular with regards to fluoride, the utility of such formulations in dental caries prevention. With this technique, a steady and constant topical action in the mouth is achieved. The new system, called IFRD and applied on the vestibular surface of the first upper molars, is able to release and to increase the daily fluoride concentration in the saliva during 6 months with no adverse effects or intolerance by patients.
Etude de l'efficacité d'un nouveau dispositif de fluorisation locale qui exerce une action topique constante dans la prévention de la carie intra-oral, fluoride, releasing device (IRFD). L'application se fait sur la surface vestibulaire de la première molaire supérieure. Le dispositif est actif durant plus de 6 mois sans effet adverse.750 - Magnesium And Antioxidant Vitamin Status And Risk Of Complications Of Ageing In An Elderly Urban Population.
This cross-sectional survey was conducted in 20 randomly selected streets in Moradbad city in North India to determine the association of magnesium and antioxidant vitamins with risk of ageing. There were 595 subjects (314 males, 281 females) between 50-84 years of age inclusive. The overall prevalence of hypo-magnesemia was 11.8 per cent (n = 60) with a prevalence of 13.2 per cent (n = 33) in males and 10.6 per cent (n = 27) in females. The prevalence of hypomagnesemia showed significant declining trend in the concentration of serum magnesium, vitamin C, vitamin E and beta-carotene and a rising trend in lipid peroxides and diene conjugates with increase in age from 50-59 years to 70-84 years in both men and women. Multivariate logistic regression analysis showed that serum magnesium, vitamin C, vitamin E and beta-carotene were significant risk factors of ageing in both men and women. The findings suggest that some urban populations of India can benefit by consuming higher dietary magnesium, potassium and antioxidant vitamins for prevention of ageing.
Etude horizontale en Inde pour déterminer s'il existe une association entre vieillissement et micronutriments. L'analyse des données montre que les taux de magnésium, vitamine C, vitamine E et bêta carotène représentent des facteurs du vieillissement. Ces constatations suggèrent que quelques populations urbaines de l'Inde peuvent bénéficier d'un apport alimentaire plus large en Mg, K, et antioxydants pour prévenir les méfaits du vieillissement.751 - Copper Supplementation And The Maintenance Of Bone Mineral Density In Middle-aged Women.
Osteoporosis is a common disease of older women in developed countries. Hormone replacement therapy (HRT) is currently the most effective way of reducing the rate of bone loss in older women. This study investigated the effects of copper supplementation over 2 years on vertebral trabecular bone mineral density (VTBMD) of a group of 73 apparently healthy women, aged 45-56 years, recruited from a general practice in north Belfast. Women were given, at random and double blind, either a supplement of 3 mg copper as amino acid chelate or a placebo to take daily. At the beginning and end of the study, VTBMD of the lumbar vertebrae (L2-4) was measured by computed tomography- scan (CT-scan) and random blood samples were taken for putative measures of copper status (erythrocyte Cu and superoxide dismutase activity). The women were seen every 3 months to monitor compliance with supplementation. There was no difference in initial and final VTBMD for the 24 women who took the copper supplement (initial VTBMD 124.6 (32.1) mg/cm3 and final VTBMD 123.8 136.3) mg/cm3) while the 32 women who took the placebo had significantly lower VTBMD at the end of the study period (initial VTBMD 120.7 (29.2) mg/cm3 and final VTBMD 113.2 (26.6) mg/cm3, paired t-test p = 0.01). Seventeen women (14 allocated the copper supplement and three the placebo) stopped taking the supplement during the study. Although copper supplementation had no effect on the putative biochemical measurements of copper status, it appeared to have reduced the loss of VTBMD in these middle-aged women over a 2 year period.
Cette étude étudie l'effet osseux d'une supplémentation en cuivre administré durant deux ans chez des femmes ménopausées. Il n'existe pas de preuve biochimique que ce traitement ait modifié le taux sérique de cuivre ni d'hypothèse sur le mécanisme d'action osseuse du cuivre. Les auteurs observent que la densité osseuse mesurée par scanner diminue significativement dans le groupe placebo et ne change pas dans le groupe recevant 3mg de cuivre.752 - The Results Of Water Fluoridation In Ireland.
The visit of Dr. Trendley Dean to Dublin in the mi/d950s helped accelerate the decision to introduce water fluoridation as a public health measure in the prevention of caries in the Republic of Ireland. A challenge to the constitutional validity of the Health (Fluoridation of Water Supplies) Act 1960 failed and in 1964 the water supplies of Dublin city were fluoridated. Over the next seven to eight years all the major urban communities in the Republic of Ireland were fluoridated. Currently, 67 percent of the 3.5 million people in the country reside in fluoridated communities. Studies conducted over the last 20 years show that residents of fluoridated communities have better dental health than those in nonfluoridated communities--the mean dmft is lower in children and the number of natural teeth present in adults is higher.
Bilan après 20 ans de fluorisation de l'eau en république d'Irlande. Un bénéfice très net sur l'état dentaire, sur la carie en particulier, est mis en évidence aussi bien chez les enfants que chez les adultes.753 - The Relationship Of Fluorosis And Brick Tea Drinking In Chinese Tibetans.
Brick tea-drinking fluorosis is an unusual environmental problem. As a result of an investigation of tea-drinking habits, total fluoride intakes, dental fluorosis, and skeletal fluorosis, this disease has been found in the Sichuan Province of China in Tibetans with a long history of drinking brick tea. The dental fluorosis investigation of 375 Tibetan children (213 males, 162 females) and 161 Han children (86 males, 75 females), 8-15 years of age, was carried out in Daofu County, Sichuan Province. According to the standard of the Chinese Health Ministry, a skeletal fluorosis survey of 658 Tibetans (264 males, 394 females) and 41 Hans (20 males, 11 females), all over 16 years old, was performed. The total fluoride intake and fluorosis were determined from a question--calculation method in all participants. The morbidities of dental fluorosis in Tibetan and Han children are 51.2% and 11.05%, respectively, and the indexes of dental fluorosis are 1.33 and 0.17 (chi 2 = 75.7, p < 0.01) respectively. The morbidity of skeletal fluorosis is 32.83% for Tibetan children and zero for the Han children. The fluoride intakes of Tibetan children and adults were 5.49 mg/person/day and 10.43 mg /person/day, respectively, in this area. Of total everyday fluoride intake, 94.2% by children and 94.4% by adults was from brick tea and zanba (r = 0.99).
Fluorose des buveurs de thé en Chine et au Tibet, en particulier dans la province de Sichuan. Il y a une longue tradition de buveurs de brick tea. La comparaison entre l'index de fluorose, dans deux populations du tibétain d'une part et les Hans d'autre part, montre que les quantités totales d'absorption de fluor et la fluorose sont élevées, chez les Tibétains (environ 51 % des enfants) et plus basses chez les Hans (11 % environ), que l'index de fluorose dentaire est de 1,33 chez les uns et 0,17 chez les autres. La morbidité de fluorose squelettique est de 32 % chez les Tibétains et 0 chez les Chinois. Les enfants tibétains absorbent en moyenne 5,49 mg/jour et les adultes 1043 mg/jour.754 - Dental Caries, Fluorosis And The Cosmetic Implications Of Different Tf Scores In 14-year-old Adolescents.
The aims of this study were to determine the opinions of a group of adolescents about the cosmetic acceptability of a range of fluorosis, investigate the prevalence and severity of fluorosis in the sample and consider the extent to which fluorosis levels were related to their dental caries experience. A random sample of 534 14-year-old pupils from the non-fluoridated industrial city of Manchester were examined for caries and fluorosis. Each subject then examined six photographs of upper anterior teeth showing a range of TF scores 0-4 and were asked to rate the appearance of each as either very poor, poor, acceptable, good or very good and to indicate whether they would request treatment if their teeth were so affected. Four hundred and seventy-six subjects (89 per cent) had TF scores of 0. Of the 58 subjects (11 per cent) with fluorosis, 27 (5 per cent) scored TF = 1/ 22 (4 per cent) TF = 2/ 7 (1 per cent) TF = 3 and one subject scored TF = 4. The subjects who had no fluorosis had a mean DMFT of 3.0 which was significantly higher than the mean of 2.2 among those with any fluorosis. The proportion of subjects who rated the photographs as poor or very poor fell from 29 per cent for TF score 0 to 15 per cent for TF score 2 and then increased to 92 per cent for TF score 3. The responses of the subjects regarding their desire for treatment matched closely with their opinions on appearance/ the majority of subjects expressed concern over the appearance of teeth with TF scores of 3 and higher. It is concluded that the prevalence of aesthetically objectionable dental fluorosis was low and that mild fluorosis was associated with a lower risk of dental caries and a more acceptable appearance. It is essential that a balanced view of the relative benefits and risks of the use of fluorides is maintained and proven benefits are not overwhelmed by largely unfounded aesthetic concerns.
Les implications esthétiques des anomalies dentaires, carie et fluorose, chez les adolescents de 14 ans en région de Manchester. Ce texte est basé sur l'impact psychologique de l'apparence de leur denture et la façon dont les adolescents les perçoivent. Il semble que la prévalence de la fluorose, comme anomalie esthétique, est faible chez ces adolescents et le petit taux de fluorose est associé avec un risque de carie faible et une apparence plus acceptable. Il faut donc essayer de mettre en balance le risque de fluorose et le bénéfice esthétique. 755 - The Caries Decline: A Review Of Reviews.
The aim of this paper is to review publications discussing the declining prevalence of dental caries in the industrialized countries during the past decades, focusing on some main conferences addressing this issue. Has there been a real decline in the prevalence of dental caries? Several excellent papers and reviews have been published, and there is a general agreement that a marked reduction in caries prevalence has occurred among children in most of the developed countries in recent decades. This fact has stimulated much debate and attempts to identify the most likely explanations for this change. The conclusion made from this review is that the various authors believe that the use of fluoride in various forms has contributed most significantly to the decline in dental caries prevalence. A number of other factors must, however, also be taken into consideration, and such factors have been extensively discussed in the various publications.
C'est une revue des publications concernant les mécanismes de diminution progressive de la prévalence des caries dentaires dans les pays industrialisés. Il y a un accord général pour dire que la réduction des caries se produit chez les enfants dans les récentes décades, et la plupart des revues croient que c'est l'utilisation du fluor, sous ses formes variées, qui a le plus contribué à cette amélioration, mais un grand nombre d'autres facteurs doivent être pris en compte.756 - A Study Of Water-borne Endemic Fluorosis In China.
Survey results are presented from 34 sentinel sites in 18 counties in endemic water-borne fluorosis areas of China through the years of 1991 and 1992. The progress in improving water to control fluorosis was very slow. By the end of 1991, only 42.1% of the villages, and 39.3% of the population, in endemic fluorosis areas had improved water supplies. In 1992 this improvement increased by only 1%. Inspection of 987 water improvement projects to reduce fluoride showed that 82.7% were continuously used, 10.3% had interrupted use, and 7.0% had been stopped or destroyed. The projects resulted in 65.4% having a water fluoride content of less than 1.0 mg/L, 21.3% had 1.0-1.5 mg/L, and 15.4% had more than 1.5 mg/L. In 34 sentinel sites, urinary fluoride content and dental fluorosis indices of 8-12 year old children decreased year by year, especially in the sites with longer water improvement and water fluoride content less than 1.0 mg/L. Symptoms and signs of adult fluorosis also decreased, but not as significantly as the urinary fluoride content and dental fluorosis of children.
Etude épidémiologique, réalisée à la suite de la baisse de la fluoration de l'eau, qui a été accompagnée d'une baisse des taux de fluor dans l'urine, et tout ceci a conduit à une amélioration de la fluorose dans les populations, en particulier chez l'enfant.757 - Magnesium In Acute Heart Infarction? The Timing Of Application Is Crucialo.
High dosage magnesium salt infusions during acute myocardial infarction led possibly due to important dissimilarities among the protocols used in LIMIT-2 and ISIS-4 to different results. The effects of magnesium aspartate infusion in acute coronary occlusion under the controlled clinical conditions of coronary angioplasty was evaluated in this prospective study. High dosage magnesium salt infusion improved ischemic tolerance by more than a factor of 2 in this clinical setting. The beneficial effects in acute myocardial infarction can only be expected, when magnesium is applicated early during the ischemic period.
Des perfusions de magnésium lors d'un infarctus du myocarde aigu ont conduit à des résultats sensiblement différents dans les études de LIMIT de ISIS 4 et ce en raison de différents protocoles utilisés. Les effets d'une perfusion de magnésium dans une occlusion coronaire aiguë ont donc été évalués dans cette étude prospective contrôlée d'angioplastie coronaire. Les perfusions à haute concentration de magnésium ont amélioré la tolérance ischémique par un facteur de plus de 2. Les effets bénéfiques au cours d'un infarctus du myocarde aigu peuvent être espérés uniquement lorsque le magnésium est apporté tout au début de la période ischémique.758 - Fluoride In Drinking Water And Human Urine In Northern And Central Poland.
The fluoride concentration in drinking water and in urine of the inhabitants of 94 localities in Northern and Central Poland was determined. The analyses were performed potentiometrically using a fluoride-specific electrode. In most of the localities the fluoride concentration in water was < 0.3 mg/l, which is far below the recommended level for caries control. In these communities fluoridation of water is advised. In six localities the water fluoride concentration was 1.2 mg/l. The elevated water fluoride is of natural (Malbork) as well as of anthropogenic (Wislinka) origin. The mean fluoride level in the urine in the investigated localities was 1.10 mg/l (range 0.10-2.67 mg/l). No significant correlation between the concentration of fluoride in drinking water and human urine was found in this study. This suggests that the elevated fluoride level in urine may be caused not only by the water fluoride, but also by the inhalation of dust particles containing fluoride, and by the diet.
Une étude concernant 94 localités du Nord et du centre de la Pologne, a permis d'évaluer le taux de fluor dans l'eau ainsi que dans les urines des habitants. La concentration en fluor dans l'eau était inférieure à 0,3 mg/l, ce qui est très en dessous du taux recommandé pour prévenir les caries. Dans ces communautés, la fluorisation de l'eau a donc été proposée. Dans 6 localités, le taux de fluor était de 1,2 mg/l, le taux moyen de fluor dans les urines chez les habitants était de 1,10 mg/l. Nous n'avons pas trouvé de corrélation significative entre la concentration dans l'eau de boisson et dans l'urine humaine. Cela suggère que les taux urinaires élevés pourraient être liés à des apports de fluor par autre chose que l'eau et notamment par des poussières, riches en fluor.759 - Fluorine Intake Of A Tibetan Population.
Measurements of food consumption of randomly selected families and fluorine levels in food and beverages were used to calculate the fluorine intake of Tibetan people living in nomadic or semi-nomadic areas of the region and regularly consuming brick tea both as a beverage and in food. The fluorine intake of these groups (children 5.49-7.62 mg day/ adults 10.43-14.48 mg/day) was much higher than that of members of a Han population living in the region (children 1.44 mg/day/ adults 2.54 mg/day). The amounts of fluorine consumed by the Tibetan inhabitants are at least twice the WHO suggested limit (2 mg/day). Tea plants are rich in fluorine, and the highest levels are found in older leaves which are used to make brick tea. We conclude that brick tea is the major source of fluorine intake by the Tibetan population studied.
C'est encore la même étude chinoise que les deux numéros précédents.