Caractères physico-chimiques des choanoleucocytes de quelques Invertébrés

Sans résumé     

De l’origine des anthropoïdes à l’émergence de la famille humaine

The human lineage has a very ancient origin, as most of the mammals. Its oldest representatives, anthropoid primates, have been described from Asia some 45 million years ago. During this long evolutionary story, two critical stages have appeared as especially important, their beginning in Asia and the emergence of hominids in Africa, some seven million years ago. These two stages are discussed hereby with new data relative to their Asian origins and their dispersal into Africa between 45 and 40 million years ago. Following this dispersal event, these primates evolved in Africa and gave rise to the early hominids. These appeared around seven million years ago and have three distinct representatives. Among them, Toumaï appears as the oldest and the closest to our ancestry, a point that is evidenced here.     

Facteurs influençant la structure des groupements de macro-invertébrés benthiques et phytophiles dans la zone littorale du Saint-Laurent (Québec)

In the littoral zone of the St-Lawrence River (Quebec, Canada), benthic and phytophilous macroinvertebrates were studied in order to find and to explain relationships between structure of these animal communities and abiotic (substrate, water depth, current velocity) or biotic (marophytes species) factors. Benthos was sampled at 16 sites in spring, when there was no macrophytic vegetation, and in summer. Phytomacrofauna was sampled at 30 sites in summer. The data were analyzed using simple and partial correlations, stepwise regression, reciprocal averaging and canonical correlation analysis.

     

Les théories de l’économie animale et l’émergence de la psychiatrie de l’Encyclopédie à l’aliénisme

The author analysesEncyclopédie’s articles devoted to nervous and mental functioning and disorders, showing that a new approach to lunacy as a mental illness, which is defined in some articles as a “general trouble of the animal economy”, progressively emerged. The term,animal economy, unified physical and moral aspects of the study of man. It was elaborated by XVIIIth century physiologists and was widely accepted by French physicians. This idea is based on the vitalistic thought of the Montpellier school, which equated life with sensibility, and on English medical conceptions of a nervous-centred organism. Later on Philippe Pinel’s work displayed the legacy of these conceptions. On one hand, the comprehensive view of physical and moral dimensions in theanimal economy neutralized the question of an organic or psychogenetic origin of madness. This enabled him to consider it as a determinate field of sensibility interactions and as a medical matter, and to legitimize the group of therapeutic practices that he namedtraitement moral. On the other hand, Pinel departed from the classical conception ofanimal economy by developing his concept of aprinciple of mania, which underlies the manifold symptoms and forms of madness, and which are only perceptible to a trained specialist (aliéniste). The historical development analysed in this article show how alienists were enabled to claim both the wholly medical nature of insanity as disease, and their specific competence as apart from the other medical disciplines. To this extent, Esquirol achieved Pinel’s scientific work.     

Contribution à l'analyse des structures forestières 2. Caractérisation et analyse du toit de la végétation

Data used come from point-height analysis. 100 sample points are arranged in 4 lines of 25, with 24 m between lines and 1 m between points on lines. At each point, vertical lists of species are compiled, by measurement strata. Such strata depth is 10 cm when mean vegetation height in the stand is lower than 4–5 m and 50 cm when heigher. A synthetic vegetation profile is obtained by sum of species presences in each measurement stratum for all 100 observations. When these profiles are bimodal, vegetation can be divided in two at the secondary minimum level: the upper part is the canopy, the lower the understorey. Only the canopy structure is dealt with in this tudy. Several parameters, describing vertical structure of woody vegetation, are defined and measured. They are: (1) maximum height, (2) upper and lower canopy limits, (3) canopy depth and (4) density. Delimitation of canopy is achieved by calculating the hypegeometric probability of realisation groups of vegetation presence, or absence, in the vertical line of sight. The thickness is the difference between the two previous values (2) and (3) and density the number of intercepts between them. Horizontal variations in those structural parameters are revealed by cumulative sum method which demonstrates different types of pattern. Relations between horizontal variations are studied by pairs; actual values compared by linear correlation analysis while concordance between patterns are characterised by the coefficient of simple concordance ofSokal etMitchner and by a binary autocorrelation coefficient.Shannon's formula enables an overall appreciation of canopy homogeneity. an example is applied to some stands ofNothofagus antarctica (Forest) Verst. in Southern Chile and Argentina. The upper canopy limits are the same upper vegetation intercepts so canopies are smooth. High correlation exists between upper and lower limits of the canopies, and low correlation between the latter and thickness and density, so canopies are uniform.     

Influence de la congélation sur le taux de fragmentation de l’ADN des spermes normaux à sévèrement altérés

Ejaculated sperm cryopreservation can be proposed in the course of anART procedure, particularly in the case of severe oligozoospermia likely to deteriorate. The aim of this study was to evaluate the influence of the freezing-thawing process on sperm DNA fragmentation (analysed by the TUNEL technique). The first step of this work consisted of adapting the TUNEL technique to perform this analysis on very poor quality sperm. A study was then performed on 72 patients divided into 4 groups according to their spermatic characteristics: group 1 [n=20] (“normal” parameters according to WHO), group 2 [n=24] (normal sperm count associated with asthenospermia and/or teratospermia), group 3 [n=16] (total sperm count between 5 and 20 M) and group 4 [n=12] (total sperm count below 5 M). Spermatic parameters and DNA fragmentation (performed by TUNEL in situ technique, 400 spermatozoa read per slide) were evaluated on raw semen - for all patients -, raw migrated sperm - for patients of group 1 and 2 -, migrated frozen-thawed sperm - for all patients-. A TUNEL technique adapted to oligospermic samples was developed, manipulating spermatozoa directly on the slide rather than in suspension, to limit spermatic sample loss. After the whole migration-freezing-thawing process, the mean DNA fragmentation rate decreased for patients in group 1 (2.9 vs 5.1%, p<0.0001) whereas this rate increased for patients in groups 2 (10.5 vs 6.8%, p<0.0001), 3 (10.7 vs 7.6%, p<0.05) and 4 (15.2 vs 8.7%, p<0.005). DNA fragmentation rates from thawed samples were also correlated with initial spermatic parameters. At the intermediary step, migration decreased DNA fragmentation rate in comparison with raw semen rate in both groups (1.9 vs 4.7% [p<0.05] in group 1; 2.5 vs 5.4% [p<0.05] in group 2). DNA fragmentation rate decreases after migration and then increases after freezing-thawing so that this rate is lower than the raw semen rate for “normal“ sperms and higher than the raw semen rate for altered sperms. Nevertheless, this DNA damage induced by cryopreservation on altered sperms remains moderate. Sperm “resistance” to cryopreservation also appears to depend on spermatic parameters. Cryopreservation may positively select spermatozoa, accelerating elimination of senescent spermatozoa by necrosis, so that early apoptotic spermatozoa from fresh ejaculate are not found in thawed samples. These results, that need to be completed by a study on a larger sample of oligospermic patients, encourage us to continue cryopreserving severely altered sperms.     

L’emploi des méthodes de la théorie des ensembles flous à l’étude biométrique de l’espèce Nummulites millecaput dans la partie occidentale de la Téthys

Application of the fuzzy set theory to the biometric evaluation of the species Nummulites millecaput in the western part of the Tethys. The goal of this paper is to demonstrate the ability of the fuzzy-set theory to contribute to the evaluation of paleontological problems. As an example, the species Nummulites millecaput, Boubée has been chosen. One hundred specimens of this species, collected from four localities (Arrimblar, Adelholzen, Dudar, and Mount-Kotuc) have been prepared (equatorial sections) for the biometric measurement of the external and internal characteristics. First a traditional statistical evaluation was performed, followed by the construction of membership functions, the latter ones expressing in the best way the transitions from one locality to the other. The results of this evaluation confirmed that from Aquitaine (France) to Armenia, the same species – Nummulites millecaput – was distributed during the Eocene. To cite this article: G. Bárdossy et al., C. R. Palevol 2 (2003).     

Influence de la distance à l'océan sur les peuplements ichtyologiques des récifs frangeants de Nouvelle-Calédonie

Coral reef fish are bound to the pelagic environment throughout their larval stage, although they spend most of their adult life on reefs. Thus, the morphology of a lagoon and the location of a reef within the lagoon may influence the nature of its fish assemblage. Because of its asymetrical shape, the SW lagoon of New Caledonia allows us to test such a hypothesis. Several fringing reefs located 4–34 km from the open ocean were compared with one another. No influence of the reef-ocean distance could be found on the global values of diversity, density or biomass. However, presence-absence data of the 343 taxa encountered are related to this distance. Similarly, ecological structures based on diet, size and mobility of fish present strong correlations with reef—ocean distance. Thus, the major effects of an increase in reef—ocean distance concern both taxinomical and ecological structures. Suggested explicative hypotheses are linked to the fish feeding habits closely related to the environment but also to their utilisation of space. Territorial behaviour seems indeed to be important in structuring reef fish assemblage.     

Les inhibiteurs spécifiques de la recapture de la sérotonine dans la dépression de l’enfant et de l’adolescent: revue des controverses récentes

European and US drug regulatory authorities have recently warned against the use of selective serotonin reuptake inhibitors (SSRIs) in childhood and adolescent depression. Through an extensive literature review on the use of SSRIs to treat depression in children and adolescents — including psychiatric clinical trials, pharmacology, and drug safety data — we will: i) describe the main arguments justifying various regulatory decisions; ii) present published data and subsequent meta-analyses; iii) discuss how to integrate the recommendations into daily clinical practice, freeing professionals from a Manichean approach. We reach the limits of evidence-based medicine, which provide the basis of the scientific work of the regulatory authorities.     

Application de la technique de PCR en temps réel à l’étude de l’ADN ancien

Real-time Polymerase Chain Reaction (PCR) for the study of ancient DNA. The properties of ancient DNA (aDNA) make difficult the retrieval of DNA sequence. The advantage of Real-Time PCR was exploited, for the first time, in the study of aDNA. We determined the optimal condition to amplify, in one round of PCR, aDNA, which should be directly sequenced. Beside the verification of aDNA authenticity, we compared two cleaning bone methods: scalpel and ethanol. The ethanol specimens showed the best DNA yield. The aDNA was extracted and amplified (mitochondrial hypervariable region I) from five skeletons exhumed from the archaeological site of Notre-Dame-du-Bourg (France), dated from 3rd to 17th century. To cite this article: R. Kefi et al., C. R. Palevol 2 (2003) 125–132.     

Radioprotection de l’entourage des patients traités à l’iode 131 pour des cancers différenciés de la thyroïde : comparaison de deux méthodes d’estimation des temps de restriction de contact

In France, it is required to give patients some written radiation safety advice following an iodine-131 therapy of thyroid. However, there is no regulatory methodology proposed to assess the restriction times required to limit radiation dose received by their family and by third persons. In this study, we compared two methods to perform the calculation of restriction times for differentiated thyroid cancer: the first one, called Global method, follows general recommendations and the second one, called PaDe method, provides customized recommendations based on the effective half-life measured for each patient during the 48 h of hospitalization. For these simulations, the input parameters for both methods were dose constraints, contact patterns, final dose rate measurement at discharge of the patient, effective half-life and dose rate variation with distance. For the Global method, these parameters were set and were not changed. For the PaDe method, the effective half-life and the final dose rate were adjusted for each patient. Comparison between the two methods was carried out for 103 patients. For 68.0 % of the patients, no restrictions were necessary according to the PaDe method whereas the Global method required restrictions to be applied during up to 2 days. For almost 16.5 % of them, restriction times estimated with the PaDe method were systematically lower. For the remaining 15.5 %, at least one contact pattern restriction had to be increased according to the PaDe method. Furthermore, with the Global method, the same instructions were given to 97.0 % of the patients. These results showed the limits of the Global method which does not consider individually tailored biological data. Eventually, the use of the personalized PaDe method optimizes the radiation protection by improving the well being of the patient or reinforcing the family and third person's protection.     

Etiologie des infertilités secondaires de l’homme

Introduction

Secondary infertility is defined as the inability to achieve a new pregnancy for a couple that has been able to procreate in the past.

Material and methods

Over a 16-year period, 49 patients consulted for male secondary infertility. Clinical, laboratory or ultrasound assessment demonstrated the cause of infertility.

Results

These patients had a mean age of 33.6 years (range: 26 to 44 years). These couples had an average of 1 living child per family, corresponding to a girl in two-thirds of cases and a boy in one-third. In these patients, infertility was due to the presence of varicocele in 15 patients (31% of cases), infection in 14 patients (29%), and varicocele associated with infection in 11 cases (22%).

Conclusion

This assessment revealed two main aetiologies, but some causes remain obvious, such as surgery with resection of the prostate or testicles, or certain cytotoxic therapies.     

Intérêt de l’introduction à la nomenclature du test de détection des HPV

Le cancer du col de l’utérus reste un problème de santé publique puisque 900 000 nouveaux cas sont diagnostiqués chaque année de par le monde [Luthra] et il est responsable en France de plus de 1600 décès par an. Pourtant, depuis plus de 40 ans, le dépistage de masse des précurseurs du cancer invasif est tout à fait réalisable et le traitement des anomalies cervicales pré-invasives amène généralement à la guérison.     

Etude de la respiration, à l’état isolé, des haplotypes de l’abeille tunisienne Apis mellifera intermissa (Buttel Reepen 1906) (Hymenoptera : Apidae)

L’étude de la respiration de l’abeille domestique, Apis mellifera intermissa, à l’état isolé a été réalisée sur les quatre haplotypes existant en Tunisie : A1, A4, A8 et A9 et sous différentes températures : 0°, 10°, 15°, 20°, 25°, 30° et 35°C. Des mesures effectuées sur 1000 abeilles isolées (250 de chaque haplotype) ont montré que la consommation d’oxygène de l’abeille varie en fonction de la température. L’intensité respiratoire des haplotypes augmente progressivement à partir de 0°C pour atteindre son maximum à 15°C. Au-delà de cette température, la consommation d’oxygène de l’abeille diminue progressivement. Pour les basses températures (0° et 10°C), la respiration de l’abeille dépend aussi du facteur génétique et la consommation d’oxygène est faible mais ne s’annule pas. Cette étude a montré qu’il existe une différence de consommation d’oxygène entre les haplotypes A1 et A8 et les haplotypes A4 et A9 pour les basses températures. Le déclenchement de la thermogenèse chez les haplotypes A1 et A8 se produit à 15°C, alors que chez les haplotypes A4 et A9, il a lieu à une température plus basse et qui est de 10°C.     

Une nouvelle faune de vertébrés continentaux,associée à des artefacts dans le Pléistocène inférieur de l’Hérault (Sud de la France), vers 1,57 Ma

A new vertebrate fauna associated with lithic artefacts from the Early Pleistocene of the Hérault Valley (southern France) dated around 1.57 Ma. Some lithic artefacts associated with an Early Pleistocene (Upper Villafranchian) vertebrate fossil assemblage have been found from a quarry exploited for basalt in the lower Hérault Valley (Languedoc, southern France) at the Lézignan-le-Cèbe locality. A preliminary patrimony expertise led us to identify about 20 vertebrate taxa, and the autumnal rainfalls revealed the presence of roughly 30 lithic artefacts of “pebble culture” type. A basalt layer dated at 1.57 My directly overlies the fossiliferous level, extends along the little hill (locus 2) yielding artefacts. These new promising data offer new perspectives to improve our understanding of Early Pleistocene ecosystems (and possibly ancient hominin occupation) of southern Europe.     

Guide à la lecture et interprétation de l’imagerie PET des plaques amyloïdes

The extracellular deposits of beta-amyloid are one of the histological lesions required for the neuropathological diagnosis of Alzheimer's disease. During the last decade, various PET tracers have been validated and have market authorization for the visualisation in vivo of amyloid plaques, with excellent sensitivity and specificity. The aim of this paper is to provide a practical guide for the visual read and interpretation of this image modality and to discuss its most recent developments for the integration in the diagnostic process and in patient management.