The adhesion molecule Necl-3/SynCAM-2 localizes to myelinated axons, binds to oligodendrocytes and promotes cell adhesion.

BACKGROUND: Cell adhesion molecules are plasma membrane proteins specialized in cell-cell recognition and adhesion. Two related adhesion molecules, Necl-1 and Necl-2/SynCAM, were recently described and shown to fulfill important functions in the central nervous system. The purpose of the work was to investigate the distribution, and the properties of Necl-3/SynCAM-2, a previously uncharacterized member of the Necl family with which it shares a conserved modular organization and extensive sequence homology. RESULTS: We show that Necl-3/SynCAM-2 is a plasma membrane protein that accumulates in several tissues, including those of the central and peripheral nervous system. There, Necl-3/SynCAM-2 is expressed in ependymal cells and in myelinated axons, and sits at the interface between the axon shaft and the myelin sheath. Several independent assays demonstrate that Necl-3/SynCAM-2 functionally and selectively interacts with oligodendrocytes. We finally prove that Necl-3/SynCAM-2 is a bona fide adhesion molecule that engages in homo- and heterophilic interactions with the other Necl family members, leading to cell aggregation. CONCLUSION: Collectively, our manuscripts and the works on Necl-1 and SynCAM/Necl-2 reveal a complex set of interactions engaged in by the Necl proteins in the nervous system. Our work also support the notion that the family of Necl proteins fulfils key adhesion and recognition functions in the nervous system, in particular between different cell types.

[End of life conflicts: perceptions of health professionals in French speaking Valais]. / Conflits en fin de vie: perceptions des professionnels de santé en valais romand.

The aim of the study was to identify the perception health professionals in palliative care had of end of life conflicts. The nature of t he conflicts,their prevalence, intensity, causes andeffects were specially addressed. Furthermore proposals of possible solutions of conflicts were investigated. A cross-sectional study was done through a self-administered questionnaire among 460 health professionals in the French Speaking Valais. The health professionals worked either in acute care hospitals, chronic health institutions, and old people nursing homes or in ambulatory palliative care units. Among the target population 233 persons replied to the questionnaire (50.6%). Among the respondents 82.4% reported to be confronted to end of life conflicts. Conflicts were quite rare (66%) and of medium or high intensity (86%). Conflicts were of medical nature (74%) or related to ethic issues (64%). Conflicts occurred among family members (68%), medical doctors and nurses (49%) or patients et medical staff (16%). Conflicts were due mainly (50-60%) to lack of communication, ambivalence among parties, differences in value systems. Mentioned (50-60%) consequences of conflicts were the waste of resources, the physical and the psychological burnout. Possible identified solutions to conflicts were interdisciplinary seminars, internal supervision procedure and the sharing of experiences. Neither age, nor gender, professional experience, working par place, training were predictive of exposure toconflicts. End of life conflicts are a common reality. They may compromise the quality of care and may contribute to high economic and social costs. They should be put on the public health agenda as a high priority.

["A good death": perception of health personnel in French-speaking Switzerland]. / La "bonne mort": Perceptions des professionnels de soins en Suisse Romande.

AIMS: To describe the perception of "Good death" among health personnel working in nursing homes in French-speaking Switzerland and to identify the differential explanatory factors. METHODS: A cross sectional study with a self-administered questionnaire, adapted from the "the' new measure of concept of good death", was done among health personnel in 5 nursing homes (2 in Geneva and 3 from Valais) in spring 2004. One hundred and sixty one persons participated at the study representing over 90% of the personel contacted. RESULTS: Four points were considered hallmarks of "Good death" by more than 80% of respondents: i.e. pain control, serenity and peace, presence of family members or close friends, respect of the last will. Up to 70% further consider as important elements the support of health professionals, the opportunity to transmit one's values and access to spiritual and/or religious support. Around 50% of respondents also consider as important "being able to chose the place of death", "having time to prepare one self", "staying conscious to the end" and "having control over body functions". These perceptions vary according to the place of work, the sex, the training in palliative care, the professional experience and of the number of deaths with which respondents were confronted. CONCLUSION: There seems to be converging opinions among health personel on what "Good death" should be. Public health decisions makers need to be informed on this.

Gene expression analysis of the critical period in the visual cortex.

The development of the primary visual cortex in animals possessing binocular vision is a classical paradigm for the study of activity-dependent neuronal plasticity. To elucidate the genetic determinants of this period of substantial plasticity, we conducted an unbiased and comprehensive transcript profiling analysis with differential display and DNA array techniques. We characterized the transcripts that change significantly between the critical and postcritical periods in the rat binocular visual cortex. We determined if these changes are specific for the visual cortex by simultaneously profiling the hippocampus and examined the impact of sensory experience on the accumulation of the identified transcripts. Our results uncover visual cortex-specific and unspecific transcription programs. Transcripts for protein kinases and phosphatases are particularly regulated. The identified transcripts support the notion that the critical period provides a permissive state for plasticity.

Uptake and translocation of phytochemical 2-benzoxazolinone (BOA) in radish seeds and seedlings.

The molecular aspects of phytochemical interactions between plants, especially the process of phytochemical translocation by the target plant, remain challenging for those studying allelopathy. 2-Benzoxazolinone (BOA) is a natural chemical produced by rye (Secale cereale) and is known to have phytotoxic effects on weed seeds and seedlings. The translocation of BOA into target plants has been poorly investigated. Therefore, the total absorption of [ring U 14C] BOA was estimated by oxidizing whole seedlings of Raphanus sativus cv. for 8 days and quantifying the radioactivity. Non-radiolabelled BOA in seedlings was also estimated by HPLC. BOA applied at 10(-3) M was readily taken up by germinated radish at a rate of 1556 nmol g(-1) FW. At these same concentrations, BOA reduced radish germination by 50% and caused a delay in radicle elongation. Exogenous BOA was responsible for the observed germination inhibition. At a concentration of 10(-5) M, BOA was taken up by germinated seeds (31 nmol g(-1) FW), but this quantity did not affect radish germination. Labelled BOA was not mineralized in the culture medium during seedling growth as no 14CO2 was recovered. Both 10(-3) and 10(-5) M BOA were translocated into radish organs, mainly into roots and cotyledons. These organs were then identified as potential physiological target sites. Cotyledons remained the target sink (44% of the total radioactivity). The kinetics of BOA uptake at 10(-3) and 10(-5) M in radish seedlings was identical: BOA accumulation was proportional to its initial concentration. A comparison between radioactivity and HPLC quantification for 10(-3) M BOA indicated that BOA (along with some metabolites) could effectively be recovered in radish organs using chromatography.