Reciprocal regulation of brain and muscle Arnt-like protein 1 and peroxisome proliferator-activated receptor alpha defines a novel positive feedback loop in the rodent liver circadian clock.

Recent evidence has emerged that peroxisome proliferator-activated receptor alpha (PPARalpha), which is largely involved in lipid metabolism, can play an important role in connecting circadian biology and metabolism. In the present study, we investigated the mechanisms by which PPARalpha influences the pacemakers acting in the central clock located in the suprachiasmatic nucleus and in the peripheral oscillator of the liver. We demonstrate that PPARalpha plays a specific role in the peripheral circadian control because it is required to maintain the circadian rhythm of the master clock gene brain and muscle Arnt-like protein 1 (bmal1) in vivo. This regulation occurs via a direct binding of PPARalpha on a potential PPARalpha response element located in the bmal1 promoter. Reversely, BMAL1 is an upstream regulator of PPARalpha gene expression. We further demonstrate that fenofibrate induces circadian rhythm of clock gene expression in cell culture and up-regulates hepatic bmal1 in vivo. Together, these results provide evidence for an additional regulatory feedback loop involving BMAL1 and PPARalpha in peripheral clocks.

Cross-cultural adaptations of the Oxford-12 HIP score to the French speaking population.

BACKGROUND: An objective measurement of surgical procedures outcomes is inherent to professional practices quality control; this especially applies in orthopaedics to joint replacement outcomes. A self-administered questionnaire offers an attractive alternative to surgeon's judgement but is infrequently used in France for these purposes. The British questionnaire, the 12-item Oxford Hip Score (OHS) was selected for this study because of its ease of use. HYPOTHESIS: The objective of this study was to validate the French translation of the self-assessment 12-item Oxford Hip Score and compare its results with those of the reference functional scores: the Harris Hip Score (HHS) and the Postel-Merle d'Aubigné (PMA) score. MATERIALS AND METHODS: Based on a clinical series of 242 patients who were candidates for total hip arthroplasty, the French translation of this questionnaire was validated. Its coherence was also validated by comparing the preoperative data with the data obtained from the two other reference clinical scores. RESULTS: The translation was validated using the forward-backward translation procedure from French to English, with correction of all differences or mistranslations after systematized comparison with the original questionnaire in English. The mean overall OHS score was 43.8 points (range, 22-60 points) with similarly good distribution of the overall value of the three scores compared. The correlation was excellent between the OHS and the HHS, but an identical correlation between the OHS and the PMA was only obtained for the association of the pain and function parameters, after excluding the mobility criterion, relatively over-represented in the PMA score. DISCUSSION AND CONCLUSION: Subjective questionnaires that contribute a personal appreciation of the results of arthroplasty by the patient can easily be applied on a large scale. This study made a translated and validated version of an internationally recognized, reliable self-assessment score available to French orthopaedic surgeons. The results obtained encourage us to use this questionnaire as a complement to the classical evaluation scores and methods.

Cyst-based ecotoxicological tests using Anostracans: comparison of two species of Streptocephalus

Cyst-based ecotoxicological tests are simple and low-cost methods for assessing acute toxicity. Nevertheless, only a few comparative studies on their sensitivity are known. In the present study, the suitability of the use of two freshwater Anostracan species, Streptocephalus rubricaudatus and S. texanus, was assessed. The impact of 16 priority pollutants (4 heavy metals, 11 organic, and 1 organometallic compounds) on these two species, as well as on Artemia salina (Artoxkit M), Daphnia magna (International Organization for Standardization 6341), and S. proboscideus (Streptoxkit F) was assessed. For indicative comparison, bioassays using Brachionus calyciflorus (Rotoxkit F) and Photobacterium phosphoreum (Microtox) were also performed. For heavy metals (K2Cr2O7, Cd2+, Zn2+, Cu2+), the sensitivity of the two studied Streptocephalus species was slightly higher than that of D. magna. It was significantly more elevated than for the marine A. salina. For organic and organometallic micropollutants [phenol, 3,5-dichlorophenol, pentachlorophenol (PCP), hydroquinone, linear alkylbenzene sulfonate, sodium dodecyl sulfate, tributylphosphate, dimethylphthalate, atrazine, lindane, malathion, tributyltin chloride (TBT-Cl)], the sensitivity of the 4 anostracan species was of the same order of magnitude as that of D. magna. Artemia salina was slightly less sensitive to some organic compounds (PCP, hydroquinone, TBT-Cl). The sensitivity of S. rubricaudatus to organic solvents was low. On the other hand, this anostracan was quite sensitive to NaCl. Thus, its use is restricted to freshwater samples. The evaluation of global practicability of these two tests confirms that cyst-based freshwater anostracans may be used to perform low-cost tests at a sensitivity comparable to that of D. magna (24 h immobilization test).

Validation de la version française du score de hanche d'Oxford-12

Fondement L'appréciation objective du résultat des actes chirurgicaux fait partie de la démarche d'évaluation des pratiques professionnelles, notamment en chirurgie orthopédique pour le résultat des prothèses articulaires. Dans cette optique, les questionnaires « auto-administrés » par les patients offrent une solution séduisante, mais peu utilisée en France. Le questionnaire anglais Oxford Hip Score en 12 questions (OHS-12) a été sélectionné pour cette étude en raison de sa facilité d'utilisation. Hypothèse Le but de ce travail était de valider la traduction française du score d'autoévaluation Oxford-12 et d'en confronter les résultats à ceux des scores fonctionnels de références, de Harris (HHS) et de Merle d'Aubigné (PMA). Matériel et méthode À partir d'une série clinique de 242 patients candidats à une arthroplastie de hanche, une validation de la traduction en langue française de ce questionnaire a été réalisée, ainsi qu'une évaluation de sa cohérence par confrontation des données obtenues en préopératoire avec celles provenant des deux scores cliniques de référence. Résultats La traduction a été validée selon le processus de traduction inverse du français à l'anglais avec correction de toute déviation ou contresens après comparaison systématisée avec le questionnaire original anglais. La moyenne du score global OHS-12 était de 43,8 points (22 à 60 points) avec une bonne distribution de la valeur globale des trois scores comparés. La corrélation était excellente entre OHS et HHS, mais une corrélation de niveau identique entre OHS et PMA n'a été obtenue que pour l'association des paramètres douleur et fonction, après exclusion du critère mobilité relativement surreprésenté dans le score PMA. Discussion et conclusion Le recours à des questionnaires subjectifs qui apportent une appréciation personnelle du résultat de l'arthroplastie par le patient est facilement applicable à grande échelle. Ce travail permet de mettre à la disposition des chirurgiens orthopédistes français une version traduite et validée d'un score d'autoévaluation fiable et internationalement reconnu. Les résultats obtenus nous incitent à privilégier l'utilisation de ce questionnaire en complément des scores et méthodes d'évaluation classiques.

"Soap-Bubble" visualization and quantitative analysis of 3D coronary magnetic resonance angiograms.

In order to compare coronary magnetic resonance angiography (MRA) data obtained with different scanning methodologies, adequate visualization and presentation of the coronary MRA data need to be ensured. Furthermore, an objective quantitative comparison between images acquired with different scanning methods is desirable. To address this need, a software tool ("Soap-Bubble") that facilitates visualization and quantitative comparison of 3D volume targeted coronary MRA data was developed. In the present implementation, the user interactively specifies a curved subvolume (enclosed in the 3D coronary MRA data set) that closely encompasses the coronary arterial segments. With a 3D Delaunay triangulation and a parallel projection, this enables the simultaneous display of multiple coronary segments in one 2D representation. For objective quantitative analysis, frequently explored quantitative parameters such as signal-to-noise ratio (SNR); contrast-to-noise ratio (CNR); and vessel length, sharpness, and diameter can be assessed. The present tool supports visualization and objective, quantitative comparisons of coronary MRA data obtained with different scanning methods. The first results obtained in healthy adults and in patients with coronary artery disease are presented.