[Creation and normalisation of a verbal episodic memory task in elderly adults: "GERIA-12"]. / Élaboration et normalisation d'une épreuve d'évaluation de la mémoire épisodique verbale chez la personne âgée: "GERIA-12".

INTRODUCTION: Early damage to episodic memory encoding and consolidation processes has been demonstrated in dementia of the Alzheimer type. However, in the domain of verbal episodic memory assessment, there are few diagnostic tools adapted to the old and oldest old as far as ease of administration and accuracy of normative data are concerned. Classic tasks are either too effortful (like the free recall/cued recall of 16 items), not sensitive enough (like the 5 words test), or insufficiently accurate for people above 70 years old in terms of normative data. AIM: The aim of this study was to develop a reduced task (in terms of number of items and number of trials) assessing verbal episodic memory in people aged between 70 and 89 years old. METHODS: The task (GERIA-12) used the same procedure as the RL/RI-16 task but the list comprised only 12 words and there were only 2 learning trials. In order to assess consolidation processes, we included 2 delayed recall trials, one after 20 minutes and the other after 24 hours. We also calculated indexes adapted from the Item-Specific Deficit Approach developed by Wright et al., which has the advantage of providing measures specific to encoding, consolidation and retrieval processes. Standardization was done with data from 220 people aged between 70 and 89 years old and belonging to 3 education levels. RESULTS: We obtained a significant effect of age and education level: scores decrease with age and increase with education. Norms have thus been calculated taking those two variables into consideration. Concerning the standardization, Barona method has been used for free recall scores while percentiles have been used for all other scores (total recall, free recall, encoding, consolidation and retrieval indexes). Normative data are also provided for intrusions and perseverations. CONCLUSION: This new task allows encoding, consolidation and retrieval processes assessment in older people and has the following advantages: the procedure is more suitable (ease and time of administration), there are accurate normative data for old and oldest old people, and there are normative data for two delayed recalls (at 20 minutes and at 24 hours).

Acceleration of keratinocyte differentiation by transient receptor potential vanilloid (TRPV6) channel activation.

BACKGROUND: Numerous studies have demonstrated the beneficial effect of Avène Thermal Spring Water (TSW) in dermatological diseases but the molecular mechanisms remain unknown. The objective of the present study was to evaluate the effect of Avène TSW on the morphological and molecular features related to the more advanced status of differentiation of human keratinocytes. MATERIAL AND METHODS: Normal human keratinocytes (NHK) were differentiated in medium powder reconstituted with Avène TSW and assessed by RT-PCR and immunohistochemistry. Calcium entry was measured by a Fura-2 AM probe. TRPV6 channel were detected by immunohistochemistry, RT-PCR and western blot. RESULTS: Treatment of NHK with Avène TSW led to an enhanced constitutive calcium entry that resulted in the increased expression of involucrin and cytokeratins 1 and 10. This enhanced constitutive calcium entry in Avène TSW-treated keratinocytes was mediated by the TRPV6 calcium channel. Moreover, Avène TSW-mediated calcium entry was due to the increase in TRPV6 expression as well as the channel abundance at the cell membrane. CONCLUSIONS: An other mechanism of action of Avène TSW is described. Avène TSW treatment induced an enhanced constitutive calcium entry mediated by TRPV6 channel leading to the acceleration of human keratinocytes differentiation.

Orai1 contributes to the establishment of an apoptosis-resistant phenotype in prostate cancer cells.

The molecular nature of calcium (Ca(2+))-dependent mechanisms and the ion channels having a major role in the apoptosis of cancer cells remain a subject of debate. Here, we show that the recently identified Orai1 protein represents the major molecular component of endogenous store-operated Ca(2+) entry (SOCE) in human prostate cancer (PCa) cells, and constitutes the principal source of Ca(2+) influx used by the cell to trigger apoptosis. The downregulation of Orai1, and consequently SOCE, protects the cells from diverse apoptosis-inducing pathways, such as those induced by thapsigargin (Tg), tumor necrosis factor α, and cisplatin/oxaliplatin. The transfection of functional Orai1 mutants, such as R91W, a selectivity mutant, and L273S, a coiled-coil mutant, into the cells significantly decreased both SOCE and the rate of Tg-induced apoptosis. This suggests that the functional coupling of STIM1 to Orai1, as well as Orai1 Ca(2+)-selectivity as a channel, is required for its pro-apoptotic effects. We have also shown that the apoptosis resistance of androgen-independent PCa cells is associated with the downregulation of Orai1 expression as well as SOCE. Orai1 rescue, following Orai1 transfection of steroid-deprived cells, re-established the store-operated channel current and restored the normal rate of apoptosis. Thus, Orai1 has a pivotal role in the triggering of apoptosis, irrespective of apoptosis-inducing stimuli, and in the establishment of an apoptosis-resistant phenotype in PCa cells.

Endothelium-dependent relaxation of rabbit aorta by acetylcholine requires ethylenediaminetetraacetic acid.

Experiments were conducted to determine if ethylenediaminetetraacetic acid (EDTA) was essential for the acetylcholine (ACh)-induced relaxation of blood vessels. Isolated rabbit aortic rings were prepared for recording isometric tension. They were maintained in Krebs bicarbonate solution with various concentrations of EDTA. With EDTA concentrations of 0 or 0.003 mM, no ACh-induced relaxation was observed; only the contractile effect of ACh was seen. With 0.03 and 0.30 mM EDTA, ACh induced relaxation with EC50 values of 0.11 and 0.098 microM, respectively. Under the experimental conditions used, EDTA was essential for demonstration of ACh-induced relaxation.

Globule leucocytes in the tracheal epithelium of rats.

Globule leucocytes are described in the tracheal epithelium of young and adult rats. They do not appear in newborn rats up to 4 weeks. Globule leucocytes migrate through the epithelium to be found free in the tracheal lumen. They seem to be retarded a certain time in the apical part of the epithelium. The inclusions of the globule leucocytes are divided into four types. The different steps in the formation and transformation process of these inclusions are suggested. The electron-dense content of the inclusions is digested by pepsin, indicating that they contain protein. This result is not conflicting with the opinion that the globule leucocytes should contain immunoglobulins.

Filamentary rod-shaped granules in Clara cells of rats.

The bronchiolar Clara cells of rats contain characteristic rod-shaped granules always surrounded by a unit membrane. These granules contain thin filaments about 9 to 10 nm in diameter lying in a pale matrix. Our morphological results suggest that the filamentary rod-shaped granules originate from the common, round-to-oval, electron-dense Clara cell granules, as we found different intermediate structures between these two kinds of granules. The electron-dense granules are digested by pepsin, whereas the filamentary rod-shaped granules are apparently not affected. The biochemical nature and the possible function of the filamentary rod-shaped granules are also discussed in relation to the secretory activity of the Clara cells.

Dense bodies in bronchiolar ciliated cells of rats.

The bronchiolar ciliated cells of rats usually contain two large electron-dense bodies which are individually surrounded by a unit membrane. They lie in a well-defined supranuclear position and may indent the nucleus. The dense material is digested by pepsin, suggesting it is composed of protein. The origin and function of these bodies are still unknown.