Designing a Massive Open Online Course (MOOC) in face-to-face sessions. A blended design to teach practical histology.

Teaching histology, through virtual microscopy in educational strategies, undeniably moved towards the digitization and distancing of teaching. The setting up of the Massive Open Online Course (MOOC) entitled "Introduction to Histology: exploring the tissues of the human body" made it possible to exploit the potential to share digital resources with a wider audience while being integrated into the teaching on-campus students. This article described the pedagogical choices prevailing during the design of the MOOC and its combination with face-to-face sessions to achieve specific learning outcomes. The pedagogical alignment of learning outcomes described according to their cognitive levels, with online and face-to-face learning activities and evaluation methods has been demonstrated. The impact of such a blended design into an academic program has been ascertained using perception and performance data. Student satisfaction and engagement as well as motivational cues were identified. The level of performance was maintained in the educational strategy implemented and made it possible to achieve the objectives expected by the teachers. The benefits of integrating a MOOC with classroom-based teaching were highlighted, as well as barriers that could hinder the successful implementation.

New insights into peripherin expression in cochlear neurons.

Peripherin is an intermediate filament protein that is expressed in peripheral and enteric neurons. In the cochlear nervous system, peripherin expression has been extensively used as a differentiation marker by preferentially labeling the type II neuronal population at adulthood, but yet without knowing its function. Since the expression of peripherin has been associated in time with the process of axonal extension and during regeneration of nerve fibers in other systems, it was of interest to determine whether peripherin expression in cochlear neurons was a static phenotypic trait or rather prone to modifications following nerve injury. In the present study, we first compared the expression pattern of peripherin and beta III-tubulin from late embryonic stages to the adult in rat cochlea. The staining for both proteins was seen before birth within all cochlear neurons. By birth, and for 2 or 3 days, peripherin expression was gradually restricted to the type II neuronal population and their projections. In contrast, from postnatal day (P) 10 onwards, while the expression of beta III-tubulin was still found in projections of all cochlear neurons, only the type I population had beta III-tubulin immunoreactivity in their cell bodies. We next investigated the expression of peripherin in axotomized cochlear neurons using an organotypic explant model. Peripherin expression was surprisingly re-expressed in a vast majority of neurons after axotomy. In parallel, the expression and localization of beta III-tubulin and peripherin in dissociated cultures of cochlear neurons were studied. Both proteins were distributed along the entire neuronal length but exhibited complementary distribution, especially within the projections. Moreover, peripherin immunoreactivity was still abundant in the growth cone, whereas that of beta III-tubulin was decreasing at this compartment. Our findings are consistent with a model in which peripherin plays an important structural role in cochlear neurons and their projections during both development and regenerative processes and which is compatible with the assumption that frequently developmentally regulated factors are reactivated during neuronal regeneration.

[Clinical experimentation with intravenously administered disopyramide]. / Experimentation clinique du disopyramide administre par voie intraveineuse

The intravenous injection of disopyramide (1.5 mg/kg) induces the return to sinus rhythm in about 60% of arrhythmias. When there exist perturbations of the cardiac rhythm, secondary to recent myocardial infarction, the percentage of success reaches 70%. The drug induces the disappearance of the extrasystoles in 80% of the cases, whatever the nature of the underlying cardiopathy. Although the secondary effects of the drug are slight, it is advisable to administer the substance in a slow intravenous injection (5 minutes), while controlling the arterial pressure and the E.C.G.

Ototoxic drugs: difference in sensitivity between mice and guinea pigs.

The development of experimental animal models has played an invaluable role in understanding the mechanisms of neurosensory deafness and in devising effective treatments. The purpose of this study was to develop an adult mouse model of ototoxic drug-induced hearing loss and to compare the ototoxicity in the adult mouse to that in the well-described guinea pig model. Mice are a powerful model organism, especially due to the large availability of antibodies, probes and genetic mutants. In this study, mice (n=114) and guinea pigs (n=35) underwent systemic treatment with either kanamycin or cisplatin. Auditory brainstem responses showed a significant threshold shift in guinea pigs 2 weeks after the beginning of the ototoxic treatment, while there was no significant hearing impairment recorded in mice. Hair cells and neuronal loss were correlated with hearing function in both guinea pigs and mice. These results indicate that the mouse is not a good model for ototoxicity, which should be taken into consideration in all further investigations concerning ototoxicity-induced hearing loss.