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PubMed2002

A 3-dimensional analysis of molar movement during headgear treatment.

Superimposition of serial cephalograms provides a limited description of tooth movement that could be complemented by data obtained from serial dental casts. The aim of this study was to develop a mathematical method for superimposing 3-dimensional data obtained from selected landmarks on longitudinally collected dental casts to describe maxillary first molar movement during headgear treatment. The material consisted of dental casts taken bimonthly from 36 children whose Class II Division 1 malocclusion was treated with straight-pull headgear during a 24-month period. Control data were collected from initial and final models of 38 subjects with a similar malocclusion who were not treated during a 24-month observation period. Spatial data from each subject's initial model were oriented similarly in an anatomically derived coordinate system, and a best-fit superimposition of palatal rugae landmarks from subsequent models allowed the measurement of molar movement. On average, headgear treatment resulted in distal movement of the molars, and the fitted net difference between treated and control subjects was 3.00 mm (SE, 0.37 mm; P < .001). Also, the headgear caused significantly more molar extrusion (0.56 mm; SE, 0.20 mm; P < .006) and buccal expansion (0.58 mm; SE, 0.17 mm; P < .001) on average than in the control group. Poor reliability of the method for measuring molar rotations indicated that they could not be determined accurately. Longitudinal description of molar movement for each subject revealed great individual variability in the amount and pattern of tooth movement. Several reasons could account for the wide range of individual variation and warrant exploration.

Case-Control Studies↗
PubMed2004

Allelic expression imbalance of the human CYP3A4 gene and individual phenotypic status.

The human cytochrome P450 3A4 (CYP3A4) plays a dominant role in the metabolism of numerous clinically useful drugs. Alterations in the activity or expression of this enzyme may account for a major part of the variation in drug responsiveness and toxicity. However, it is generally accepted that most of the known single nucleotide polymorphisms in the coding and 5'-flanking regions are not the main determinants for the large inter-individual variability of CYP3A4 expression and activity. We show that the allelic variation is critically involved in determining the individual total hepatic CYP3A4 mRNA level and metabolic capability. There exists a definite correlation between the total CYP3A4 mRNA level and allelic expression ratio, the relative transcript level ratio derived from the two alleles. Individuals with a low expression ratio, exhibiting a large difference of transcript level between the two alleles, revealed extremely low levels of total hepatic CYP3A4 mRNA, and thus low metabolic capability as assessed by testosterone 6beta-hydroxylation. These results present a new insight into the individualized CYP3A4-dependent pharmacotherapy and the importance of expression imbalance to human phenotypic diversity.

Alleles↗
PubMed2002

Exposure to carcinogenic air pollutants among policemen working close to traffic in an urban area.

OBJECTIVE: This study evaluates individual airborne exposure to gaseous and particulate carcinogenic pollutants in a group of policemen working close to traffic in the center of Grenoble, France. METHODS: Sixty-two personal active air samples were collected during the workshifts of eight policemen in summer and in winter during the occurrence of the thermal inversion phenomenon. Seventeen stationary air samples were monitored in the policemen's work area during the same period with the same sampling devices as used for the personal samples. The respirable particle concentration was determined using the gravimetric method. The concentrations of polycyclic aromatic hydrocarbons and aldehydes were measured with high-performance liquid chromatography with fluorimetric or ultraviolet detection. The benzene-toluene-xylene levels were determined with gas chromatography with flame ionization detection. RESULTS: The median concentration of the personal samples for respirable particles was 55.5 microg/m3 in the summer and 124 microg/m3 in the winter. The corresponding values were 0.10 and 0.28 ng/m3 for benzo(a)pyrene, 14 and 21 microg/m3 for formaldehyde, and 10.5 and 23.5 microg/m3 for benzene. The median personal concentrations were equal to or higher than the corresponding stationary levels for both seasons. Compared with the concentration of aldehydes, the concentrations of respirable particles, polycyclic aromatic hydrocarbons, and benzene-toluene-xylene appeared to show higher individual variability. CONCLUSIONS: The occupational exposure of policemen does not exceed any currently applicable occupational or medical exposure limits. Individual particulate levels should preferably be monitored in Grenoble in winter to avoid underestimations.

Air Pollutants, Occupational↗
PubMed2002

Sensitivity analysis and auto-calibration of an integral dynamic model for river water quality.

ESWAT--Extended Soil and Water Assessment Tool--was developed to allow for an integral modelling of the water quantity and quality processes in river basins. ESWAT is a physically based, semi-distributed model, with a moderate-to-large number of parameters and input and output variables (depending on the desegregation scheme). An auto-calibration procedure was implemented for the optimisation of the process parameters. The procedure is based on a new approach for multi-objective calibration and incorporates the algorithms of the Shuffled Complex Evolution Method. The optimisation uses a global optimisation criterion, whereby several output variables can be taken into account simultaneously. A statistical method enables the aggregation of the objective functions for individual variables, hereby avoiding the weighting problem. To select the important parameters for the optimisation, a sensitivity analysis precedes the calibration. The latter analysis is based on the One-factor-At-a-Time (OAT) design approach. The sensitivity analysis and the calibration procedure are applied to the river Dender in Belgium. The river is characterised by high pollution loads and long residence times in summer periods.

Calibration↗
PubMed2006

[Evaluation of the ultrasonographic features of axillary lymph node metastasis in breast cancer].

OBJECTIVE: To analyze the ultrasonographic features of axillary lymph node metastasis in breast cancer patients, and to evaluate the accuracy of these features by Receiver Operating Characteristic (ROC) curve. METHODS: Ultrasonography was carried out in 113 patients (mean age 56.5 yr, range 29 - 77 yr). The ultrasonographic features of the primary tumor and the axillary lymph node were observed. Univariate analysis was performed by Chi-squared test and Fisher exact test, and multivariate analysis to determine independent significant individual variables by multiple logistic regression analysis. ROC curve analysis was done to determine the sensitivity and specificity of individual and combined ultrasonographic features in distinguishing metastatic lymph node from the normal one. RESULTS: The primary tumor size, abundance of blood supply in the primary tumor, longitudinal-transverse diameter ratio, cortex-hilum thickness ratio (on the longitudinal section), abnormal cortex thickness, distribution of intra-nodal vascularity of axillary lymph nodes were found to be statistically significant factors by univariate analysis. The primary tumor size, longitudinal-transverse ratio and cortex-hilum thickness ratio of lymph node were proved to be significant independent predictors of axillary lymph node metastasis by logistic regression analysis. Through ROC analysis, the combination of these independent ultrasonographic feature predictors was found to contribute significantly in differentiating metastatic lymph node from the normal with a sensitivity of 88.6% and specificity of 84.5%. CONCLUSION: Axillary ultrasonography is helpful in staging the axillary lymph node in breast cancer patient. The primary tumor size, longitudinal-transverse diameter ratio and cortex-hilum thickness ratio of lymph node are the main features to determine whether metastatic involvement is present or not.

Adult↗
PubMed1986

Fluctuations of NK activity in human volunteers receiving vitamin A or a placebo daily.

This paper examines the effect of prolonged daily administration of Vitamin A on NK activity. A placebo and a pill containing 50,000 IU retinol acetate (RA) were taken daily for 120 days by 5 and 6 healthy volunteers respectively. NK activity was determined on days -45, -40, -30 and -10 to calculate each volunteer's inherent variability and then twice a month throughout the administration period. To minimize the experimental variability, an internal control was inserted in each assay. This consisted of two lymphocyte preparations from two healthy individuals divided into cryopreserved aliquots. The cytotoxicity percentage in each assay was corrected against these reference standards and converted into NK values by angular transformation. No increase in NK activity was noted during the study in the group receiving RA. A marked individual variability, however, was noted in both groups.

Female↗
PubMed2003

Predictor variables in competency to stand trial decisions.

Clinicians possess significant discretion in competency to stand trial assessment. Therefore, it is paramount to explore the contribution of individual variables to ensure that the decision-making process is devoid of bias and solely relates to the legal criterion. To test for the possibility of bias in clinical decision-making, we examined the predictive efficiency of clinical, criminological, and sociodemographic variables in a sample of 468 criminal defendants referred for competency evaluations. Only clinical diagnostic variables and employment status were significant predictors. This finding supports the idea that examiner decisions of competency appear to be unbiased and relate primarily to a defendant's functional ability.

Aged↗
PubMed2000

Pharmacogenetics: the molecular genetics of CYP2D6 dependent drug metabolism.

INTRODUCTION: Genetic variation of drug metabolising enzymes has been recognised as one of the major causes of the inter-individual variability to drug response. The vast majority of drugs are degraded via a small number of metabolic pathways, mainly by microsomal P-450 enzymes localised in the liver and, to a minor extent, in the small intestine. Of these, CYP3A4 is the isozyme involved in the metabolism of most of the clinically useful drugs (50%). This is followed by CYP2D6 (20%), CYP2C9 and CYP2C19 (15%). In addition, minor pathways are catalysed by CYP2E1, CYP1A2, CYP2A6 and unidentified P-450s. Almost 40% of human P-450 dependent drug metabolism is carried out by genetically polymorphic enzymes. Polymorphisms generated by mutations in the genes for these enzymes cause quantitatively or qualitatively altered enzyme expression or activity through multiple molecular mechanisms. While CYP3A4 genetic polymorphisms are just beginning to be unraveled, extensive studies on the CYP2D6 gene over the last decade have identified at least 53 alleles. Of these, more than 20 of them are known to significantly alter the metabolism of CYP2D6 substrates. METHODS: This article reviews the information derived from various studies over the past decade and explains the molecular basis of functional differences in CYP2D6 variants, especially with respect to inter-ethnic differences and their clinical implications. RESULTS: CYP2D6 activity ranges from complete absence to ultra-rapid metabolism. Large inter-individual and inter-ethnic variability exists in the activity of the enzyme, and consequently in the disposition of drugs undergoing oxidative metabolism. CONCLUSIONS: Pharmacokinetic differences resulting from these polymorphisms show potentially important clinical consequences.

Alleles↗
PubMed2006

The influence of sulcal variability on morphometry of the human anterior cingulate and paracingulate cortex.

Human anterior cingulate (ACC) and paracingulate (PaC) cortices play an important role in cognitive and affective regulation and have been implicated in numerous psychiatric and neurological conditions. The region they comprise displays marked inter-individual variability in sulcal and gyral architecture, and although recent evidence suggests that this variability has functional significance, it is often ignored in automated and region-of-interest (ROI) morphometric investigations. This has lead to confounded interpretation of results and inconsistent findings across a number of studies and in a variety of clinical populations. In this paper, we present a reliable method for parcellating the dorsal, ventral, and subcallosal ACC and PaC that accounts for individual variation in the local cortical folding pattern. We also investigated the effect of one well characterized morphological variation, the incidence of the paracingulate sulcus (PCS), on regional volumes in 24 (12 male, 12 female) healthy participants. The presence of a PCS was shown to affect both ACC and PaC volumes, such that it was associated with an 88% increase in paracingulate cortex and a concomitant 39% decrease in cingulate cortex. These findings illustrate the potential confounds inherent in morphometric approaches that ignore or attempt to minimize inter-individual variations in sulcal and gyral anatomy and underscore the need to consider this variability when attempting to understand disease processes or characterize brain structure-function relationships.

Adult↗
PubMed1999

Circulating venous bubbles in recreational diving: relationships with age, weight, maximal oxygen uptake and body fat percentage.

Decompression sickness (DCS) is recognized as a multifactorial phenomenon depending on several individual factors, such as age, adiposity, and level of fitness. The detection of circulating venous bubbles is considered as a useful index for the safety of a decompression, because of the relationship between bubbles and DCS probability. The aim of this work was to study the effects of individual variables which can be assessed non invasively, on the grades of bubbles detected 60 min, after diving by means of Doppler monitoring, in a sample of 40 male recreational scuba divers. The variables investigated were: age, weight, maximal oxygen uptake (VO2max) and percentage of body fat (%BF). Bubble signals were graded according to the code of Spencer. The relationships between the bubble grades (BG) and the variables investigated were studied using two methods: the differences between the average values of each variable at each BG were analyzed by the Scheffe test. Then we performed the non-parametric Spearman correlation analysis. Significant differences (P < 0.05) were found (Scheffe test) between average values of the variables at grade 0 and 3 (age: P = 0.0323; weight: P = 0.0420; VO2max: P = 0.0484), except for %BF (P = 0.1697). Relationships with P < 0.01 were found (Spearman correlation) between BG and the variables: age: p = 0.486, P = 0.0024; weight: p = 0.463, P = 0.0039; VO2max: p = -0.481, P = 0.0027; except for %BF: p = 0.362, P = 0.0237. This work showed that bubble production after hyperbaric exposures depends on several individual factors. The effects of age, weight and VO2max are more significant than the effect of %BF. We concluded that to take into account such variables in decompression tables and diving computer programs should allow to adapt the decompression procedures to individual risk factors and reduce the DCS probability.

Adult↗
PubMed2004

Accuracy of plain films, and the effect of experience, in the assessment of ankle effusions.

OBJECTIVE: To investigate the accuracy of plain radiographs, and the effect of observer experience, in the assessment of ankle effusions compared with an MRI gold standard. DESIGN AND PATIENTS: Anteroposterior (AP) and lateral radiographs of the ankle of 39 patients were evaluated by four observers, ranging from first-year radiology resident to an attending musculoskeletal radiologist. Observers independently graded the lateral films from 0 to 5 at one sitting, and the AP films at a second sitting. All patients had an MRI scan performed within 48 h of the ankle radiographs, on which distention of the anterior recess was used as the gold standard for an effusion. RESULTS: Lateral radiographs had variable sensitivity (range 17-63%), but specificity (81-94%) was usually high. AP radiographs similarly had variable sensitivity (15-55%), but their specificity (63-75%) was surprisingly good. Overall, sensitivity and specificity were inversely proportional and more related to individual variability than experience (observer 1, 53% and 81%; observer 2, 17% and 94%; observer 3, 63% and 88%; observer 4, 21% and 94%); however, individual sensitivity and specificity were consistent between AP and lateral radiographs (observer 1, 53% and 81%, 50% and 65%; observer 2, 17% and 94%, 15% and 75%), observer 3, 63% and 88%, 55% and 63%; observer 4, 21% and 94%, 25% and 70%). Positive predictive value was reasonably good for lateral radiographs (range 75-86%); however, it was fairly low for AP radiographs (38-61%). Negative predictive value was low for both lateral (50-67%) and AP (47-58%) radiographs. Accuracy was low for both AP (45-59%) and lateral (53-74%) radiographs. As expected, individual accuracy was consistently higher for lateral radiographs than for AP radiographs (observer 1, 65% and 58%; observer 2, 53% and 45%; observer 3, 74% and 59%; observer 4, 54% and 48%). CONCLUSIONS: For the diagnosis of ankle effusions the overall accuracy of radiographs was surprisingly low. Quite surprisingly, the diagnosis of effusions on AP radiographs was not much poorer than on lateral films. Results, however, varied little with experience and training.

Adult↗
PubMed2006

Pharmacokinetic variability of newer antiepileptic drugs: when is monitoring needed?

A new generation of antiepileptic drugs (AEDs) has reached the market in recent years with ten new compounds: felbamate, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, pregabalin, tiagabine, topiramate, vigabatrin and zonisamide. The newer AEDs in general have more predictable pharmacokinetics than older AEDs such as phenytoin, carbamazepine and valproic acid (valproate sodium), which have a pronounced inter-individual variability in their pharmacokinetics and a narrow therapeutic range. For these older drugs it has been common practice to adjust the dosage to achieve a serum drug concentration within a predefined 'therapeutic range', representing an interval where most patients are expected to show an optimal response. However, such ranges must be interpreted with caution, since many patients are optimally treated when they have serum concentrations below or above the suggested range. It is often said that there is less need for therapeutic drug monitoring (TDM) with the newer AEDs, although this is partially based on the lack of documented correlation between serum concentration and drug effects. Nevertheless, TDM may be useful despite the shortcomings of existing therapeutic ranges, by utilisation of the concept of 'individual reference concentrations' based on intra-individual comparisons of drug serum concentrations. With this concept, TDM may be indicated regardless of the existence or lack of a well-defined therapeutic range. The ten newer AEDs all have different pharmacological properties, and therefore, the usefulness of TDM for these drugs has to be assessed individually. For vigabatrin, a clear relationship between drug concentration and clinical effect cannot be expected because of its unique mode of action. Therefore, TDM of vigabatrin is mainly to check compliance. The mode of action of the other new AEDs would not preclude the applicability of TDM. For the prodrug oxcarbazepine, TDM is also useful, since the active metabolite licarbazepine is measured. For drugs that are eliminated renally completely unchanged (gabapentin, pregabalin and vigabatrin) or mainly unchanged (levetiracetam and topiramate), the pharmacokinetic variability is less pronounced and more predictable. However, the dose-dependent absorption of gabapentin increases its pharmacokinetic variability. Drug interactions can affect topiramate concentrations markedly, and individual factors such as age, pregnancy and renal function will contribute to the pharmacokinetic variability of all renally eliminated AEDs. For those of the newer AEDs that are metabolised (felbamate, lamotrigine, oxcarbazepine, tiagabine and zonisamide), pharmacokinetic variability is just as relevant as for many of the older AEDs. Therefore, TDM is likely to be useful in many clinical settings for the newer AEDs. The purpose of the present review is to discuss individually the potential value of TDM of these newer AEDs, with emphasis on pharmacokinetic variability.

Amines↗
PubMed1998

Developmental changes and variability in the early lexicon: a study of French children's naturalistic productions.

This paper investigates developmental changes, as well as inter-linguistic and inter-individual variations, in the expansion and composition of French children's early lexicons. Two studies were conducted using children's naturalistic productions: a longitudinal study of one child between 1;2 and 2;6, and a cross-sectional study of two groups (12 children each) aged 1;8 and 2;6. Analyses indicate that lexical productivity (measured in types, tokens, and new words) strongly increased with age, whereas lexical diversity showed almost no developmental progression. Nouns and para-lexical elements (including interjections, fillers or formulas) were predominant until 1;8 and decreased over time, while predicates and grammatical words increased. As compared to English, French development was characterized by less frequent nouns, initially more frequent predicates, and a remarkable expansion of grammatical words. Inter-individual variability in lexical productivity, in lexical diversity, and in the proportions of different categories was more marked at 1;8 than at 2;6. Lexical profiles found at 1;8 suggest the existence of more diversified organizational patterns than those captured in the referential-expressive distinction.

Age Factors↗
PubMed2002

Daily temporal organization of laying in Japanese quail: variability and heritability.

In birds, many behavioral and physiological processes that occur during reproduction show daily rhythms in response to environmental temporal constraints. In this study, the individual daily organization of laying and its genetic determinant in Japanese quail (Coturnix coturnix japonica) were analyzed. For this purpose, the oviposition time of 102 randomly chosen females, maintained in long-day photoperiodic conditions (LD 14 h:10 h) for 1 mon was observed and extreme phenotypes selected. Laying is characterized by two parameters: oviposition interval and laying hour. The birds showed a specific time of laying during 24 h. All eggs were laid in the afternoon between 6.5 and 14 h after lights on (HALO). Two laying profiles were determined: 20% of females with an oviposition interval greater than 24 h (24.7 +/- 0.2 h) (the "delayed" profile) laid progressively later each day until a pause day. The remaining 80% of the females laid at the same time each day, with few pause days and an oviposition interval close to 24 h (24.0 +/- 0.2 h) (the "stable" profile). Among the females, showing this last profile, an intra-individual stability and an inter-individual variability of laying hour was established. Two extreme laying phenotypes were then determined: the "early" phenotype (E) for females laying on average between 7.5 and 9.5 HALO and the "late" phenotype (L) for females laying between 12.5 and 14HALO. In order to study the genetic basis of the laying hour, three females of each extreme phenotype were selected and crossed with two different males. The E and L females produced 57 F1E and 42 F1L daughters, respectively. F1 females displayed both laying profiles. However, the proportion of females displaying a "delayed" profile was higher in the L line (50%) than in the E line (29.8%). For the "stable" daughters, artificial selection induced an advance in laying hour of 4.7% for the E line and a delay of 4.7% for the L line. Realized heritability was estimated at 0.5. Moreover, the laying hour of the daughters was correlated positively to that of the mothers (N = 61; r = 0.45). These results support the notion of heritability of oviposition time in Japanese quail.

Analysis of Variance↗
PubMed1980

Toxicological implications of polymorphic drug metabolism.

The occurrence of genetic polymorphisms of drug metabolism means that populations contain subgroups (phenotypes) that differ sharply in their abilities to effect a number of metabolic reactions. Because of this, major interphenotype differences occur in responsiveness to drugs and toxic substances. The well established genetic polymorphisms of acetylation and hydrolysis illustrate the important association that exists between phenotype and propensity to develop toxic and exaggerated responses to some substances. Recently, for metabolic oxidation, a new genetic polymorphism of drug metabolism has been described and it promises to provide a better understanding of inter-individual variability in the metabolic handling of, and responsiveness to, drugs and toxic substances. The following effects of the polymorphism are described here: (a) its influence in determining variable presystemic metabolism and hence systemic drug availability; (b) its role in determining alternative toxic pathways of metabolism in individuals who have a genetically determined impairment of oxidative capacity and (c) its influence on the development of agranulocytosis associated with metiamide administration.

Alleles↗
PubMed2003

Intra-individual variations of fasting plasma lipids, apolipoproteins and postprandial lipemia in familial combined hyperlipidemia compared to controls.

BACKGROUND: The intra-individual variability of plasma lipids and apolipoproteins has not been studied systematically in familial combined hyperlipidemia (FCHL). METHODS: Intra-individual changes in fasting plasma lipids and apolipoproteins B and AI were determined in 18 untreated FCHL subjects and 16 unrelated, normolipidemic subjects. Participants were matched for gender, age and body mass index. The mean follow-up period of fasting plasma lipids was 48.91 +/- 35.46 (mean +/- S.D.) days. Postprandial lipemia was determined on 3 different days in 1 week in 90 healthy controls and 17 untreated FCHL subjects by the area under the diurnal capillary triglyceride curve (TGc-AUC). RESULTS: The coefficients of variation (CVs) for fasting plasma TG were similar between FCHL (23.2 +/- 10.2%) and controls (20.4 +/- 8.2%). The CVs for HDL-C, apo B and apo AI were the lowest of all fasting plasma measurements in both groups and there was no significant difference between FCHL (12.8 +/- 8.2%, 13.2 +/- 15.8% and 6.4 +/- 5.2%, respectively) and controls (11.4 +/- 4.3%, 11.3 +/- 10.6% and 7.8 +/- 4.6%, respectively). The CVs for postprandial lipemia were not different between FCHL (15.9 +/- 11.3%) and controls (15.1 +/- 11.0%), and were significantly lower than the CV of fasting capillary TG (TGc) in the same period (36.3 +/- 24.7% and 24.9 +/- 17.2%, respectively). CONCLUSIONS: Our study does not provide evidence for short-term major changes in fasting or postprandial lipemia or apolipoproteins in FCHL when systematically compared to healthy controls.

Apolipoproteins↗
PubMed1988

Microalbuminuria in diabetic subjects with chronic peripheral neuropathy.

Fifty-five patients with chronic peripheral neuropathy, 31 with and 24 without retinopathy, had albumin excretion rates determined on 2-h supine urine collections on three occasions by a radioimmunoassay method. Four patients with retinopathy had albustix-positive proteinuria and were excluded from subsequent analysis. Microalbuminuria was found in 20 of the 27 patients with retinopathy compared with 10 of the 24 patients with neuropathy alone. The mean albumin excretion rate (AER) was higher in neuropathic patients with retinopathy than in those patients with neuropathy alone (41.2 +/- 40.3 vs 18.8 +/- 33.2 micrograms/min, P less than 0.01). Multivariate analysis of the data was performed and this revealed a correlation coefficient of R2 = 0.33 (P less than 0.01) for AER as the dependent variable with respect to the independent variables HbA1, systolic blood pressure and known duration of diabetes. There was, however, no significant contribution separately of these individual variables to the regression equation. Microalbuminuria was significantly associated with retinopathy although almost half of the patients with neuropathy alone had microalbuminuria. The association between microalbuminuria and neuropathy even in the absence of retinopathy provides support for a microvascular element in the pathogenesis of diabetic neuropathy.

Albuminuria↗
PubMed2001

[Determination of the state of emaciation of eel (Anguilla Anguilla) in migration in coastal and estuary zones].

The objective of this work is to characterise the variations of the quality of the glass eels recruitment during a season of migration, from November till March and before and after the transition from marine to continental environment. The emaciation state measured from the ratio DNA/Dry weight and percentage of body water is analysed from a sampling of glass-eels collected at sea and in estuary, in the South of the Bay of Biscay during the migration period 1999/2000. The length and the mass are taken into account, they decrease during the season while the individuals are more and more pigmented. However, our work shows that groups of glass eels arriving on the coasts of the Bay of Biscay are homogeneous from the point of view of their energetic and hydride reserves with a high individual variability within these groups. Also no significant difference in losses of water and energetic reserve were observed among the individuals migrating at the beginning and during tide stream. Fluctuations of the biochemical indication and the percentage of water between the glass eels caught in sea and in estuary show that the transition between maritime and continental environment is not a mobilising event of a lot of energy for glass eels. Differences were only observed in December.

Anguilla↗