High-fidelity simulation in training dental students for medical life-threatening emergency.

INTRODUCTION: Any dental surgeon may be faced with a critical life-threatening emergency situation. In our university, all students in dentistry receive a standard course on emergency first aid. The aim of this prospective, comparative, single-centre study was to determine whether additional training on a high-fidelity patient simulator would improve student performance. METHODS: After approval by an Ethical Committee and written informed consent, the students of the Simulation group (n=42) had full-scale high-fidelity training on a patient simulator SimMan 3G™ (3 hours by six students). They participated in pairs in two scenarios (airway obstruction, seizures, allergies, vasovagal syncope, asthma, chest pain). The first scenario was simple, and the second was a progression to cardiac arrest. Three months later, the Simulation group and the Control group (n=42) participated in a test session with two scenarios. The primary end point was the score at the test session (with a standardised scoring grill, direct observation and audio-video recording). Data were median and 25%-75% percentiles. RESULTS: High-fidelity training strongly improved the score on the test obtained by the students of the Simulation group (146 [134-154]) which was much higher (P<.0001) than in the Control group (77 [67-85]). Technical as well as non-technical skills components of the scores were improved. In addition, performances of the Simulation group were increased between the training and the test. Simulation session was very positively assessed by the students. CONCLUSIONS: The results support the systematic introduction of training to critical life-threatening emergency situations on high-fidelity patient simulators the dentistry curriculum. The impact on clinical practice in the dental office remains to be assessed.

82Sr purification procedure using Chelex-100 resin.

(82)Rb is a positron-emitting radionuclide widely used in nuclear cardiology. One great advantage is its availability through a generator loaded with (82)Sr. (82)Sr can be produced in a high energy cyclotron by irradiating rubidium chloride target with proton beam. In this paper, we present an extensive study (elution profiles, effect of the elution flow rate) on the use of Chelex-100 resin and ammonia buffer. No significant effect of flow rate was evidenced between 1 and 10mL/min leading us to propose a purification process which can be easily automated.

A molecular phylogeny shows the single origin of the Pyrenean subterranean Trechini ground beetles (Coleoptera: Carabidae).

Trechini ground beetles include some of the most spectacular radiations of cave and endogean Coleoptera, but the origin of the subterranean taxa and their typical morphological adaptations (loss of eyes and wings, depigmentation, elongation of body and appendages) have never been studied in a formal phylogenetic framework. We provide here a molecular phylogeny of the Pyrenean subterranean Trechini based on a combination of mitochondrial (cox1, cyb, rrnL, tRNA-Leu, nad1) and nuclear (SSU, LSU) markers of 102 specimens of 90 species. We found all Pyrenean highly modified subterranean taxa to be monophyletic, to the exclusion of all epigean and all subterranean species from other geographical areas (Cantabrian and Iberian mountains, Alps). Within the Pyrenean subterranean clade the three genera (Geotrechus, Aphaenops and Hydraphaenops) were polyphyletic, indicating multiple origins of their special adaptations to different ways of life (endogean, troglobitic or living in deep fissures). Diversification followed a geographical pattern, with two main clades in the western and central-eastern Pyrenees respectively, and several smaller lineages of more restricted range. Based on a Bayesian relaxed-clock approach, and using as an approximation a standard mitochondrial mutation rate of 2.3% MY, we estimate the origin of the subterranean clade at ca. 10 MY. Cladogenetic events in the Pliocene and Pleistocene were almost exclusively within the same geographical area and involving species of the same morphological type.

Doubly radiolabeled liposomes for pretargeted radioimmunotherapy.

The aim of this study was to design liposomes as radioactivity carriers for pretargeted radioimmunotherapy with favorable pharmacokinetic parameters. To monitor the liposomes integrity in vivo, their surface was radiolabeled with indium-111 bound to DTPA-derivatized phosphatidylethanolamine (DSPE-DTPA) and the aqueous phase was labeled by using an original active loading technique of radioiodinated Bolton-Hunter reagent (BH) that reacts with pre-encapsulated arginine to form a positively charged conjugate ((125)I-BH-arginine). Different formulations of doubly radiolabeled liposomes were tested in vitro and in vivo to evaluate radiolabeling stability, integrity of the vesicles and their pharmacokinetics. Radiolabeling yields were high (surface >75%, encapsulation >60%) and stable (>85% after 24 h in serum 37 degrees C). In vivo, the pharmacokinetic behavior of doubly radiolabeled liposomes was strongly dependant on the formulation. Blood clearance of PEGylated liposomes (DSPC/Chol/DSPE-DTPA/DSPE-PEG5%) was 0.15 mL/h compared to a conventional formulation (DSPC/Chol/DSPE-DTPA: clearance 1.44 mL/h). Non-encapsulated BH-arginine conjugate was quickly eliminated in urine (clearance 6.04 mL/h). Blood kinetics of the two radionuclides were similar and radiochromatographic profiles of mice serum confirmed the integrity of circulating liposomes. The significant reduction of activity uptake in organs after liposome catabolism (liver and spleen), achieved by the rapid renal elimination of (125)I-BH-arginine, should bring significant improvements for targeted radionuclide therapy with sterically-stabilized liposomes.

The role of dispositional and situational factors in cognitive interference.

Two studies investigated the cross-temporal stability and cross-situational consistency of cognitive interference. In Study 1, 70 college students reported on the intrusive thoughts they experienced during 2 course examinations and a self-reflective task. In Study 2, 55 college athletes reported on intrusive thoughts following 2 course examinations and 2 regular season football games. Major findings were (a) cognitive interference showed both cross-temporal stability and cross-situational consistency, (b) it was predicted by a measure of dispositional intrusive thinking, (c) the link between cognitive interference and dispositional intrusive thinking was not accounted for by indices of depressive symptomatology and trait anxiety, and (d) the degree of cross-situational consistency of cognitive interference and the content of these intrusive thoughts were influenced by situational factors.