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Notes: Multiple technologies are under development to identify plaque composition and vulnerability. This review article is intended to provide basic knowledge to the interventional cardiologist and the clinician about spectroscopy. The concept of light, the wavelength unit and the electromagnetic spectrum are discussed. Different types of spectra analysis including nuclear magnetic resonance, Raman, fluorescence and diffuse reflectance near-infrared spectroscopy are then carefully reviewed. Experimental data to identify atherosclerotic plaque composition for each of these techniques is provided. Potential benefits and challenges are addressed. Finally, diffuse reflectance near-infrared spectroscopy is discussed in more detail as a promising technique to characterize plaque vulnerability in humans. (J Interven Cardiol 2003;16:243–252)

Notes: We propose an original method to mark patch test sites. A transparency is applied on the patient's back, surrounding patch tests, immediately after their application. Marks are performed with an erasable pen on test sites and on permanent skin lesions like naevi. For further readings performed after patch test removal, the transparency applied on the patient's back permits the attribution of a positive reaction. This method is clean (without ink marks on skin and without contamination of clothing), more comfortable for the patient (allowing back washing immediately after the 1st reading, never inducing allergy to inks), durable (permitting delayed readings after several days or weeks) and inexpensive (because transparencies can be reused).

Notes: 1. The application of functional ecology models to aquatic plants often relies on morphological and life-history traits which may reflect, in part, the phenotypic plasticity displayed by aquatic plants. The present study was designed to evaluate the use of physiological traits, such as nutrition patterns, to describe aquatic plant strategies along a gradient of increasing resource availablity.2. Taking phosphorus (P) as an example, nutrition-use efficiencies were evaluated in five species, through the P-content in plant tissues, the variations in P-content according to nutrient availability and the perenniality of P-storage. Plasticity in P-storage was also investigated in Ranunculus peltatus, a morphologically highly plastic species.3. In 2001, P-content was analysed in Callitriche hamulata, C. obtusangula, C. platycarpa, Elodea nuttallii and R. peltatus tissue samples. These five species were sampled at nine different sites in streams along an increasing resource gradient in the Northern Vosges Biosphere Reserve (NE France). Variations of P-content in the roots, stems and dissected and floating leaves of R. peltatus were also studied.4. Only C. platycarpa and R. peltatus were found to occur in low nutrient availability conditions. Callitriche hamulata, C. obtusangula and E. nuttallii were restricted to mesotrophic and eutrophic sites. The highest nutrient-use efficiency was found for E. nuttallii which was able to adapt its P-storage to varying resource availabilities. Ranunculus peltatus was able to store high concentrations of P, but its P-integration within the vegetative structure was less efficient under eutrophic conditions. Callitriche spp. appeared to have relatively low nutrient-use efficiencies, although C. obtusangula displayed a high P-content. While P was stored preferentially in roots in R. peltatus populations occurring in nutrient-rich sites, there was no particular P-storage organ for populations from nutrient-poor sites.5. On the basis of P-usage, R. peltatus and E. nuttallii presented competitor traits, C. hamulata and C. platycarpa displayed stress-tolerant nutrient signatures and for C. obtusangula, ruderal or competitor characteristics dominated. The use of physiological traits, such as nutrition patterns, may provide valuable, complementary information about aquatic plant strategies, independent from the influence of morphological trait plasticity often displayed by these plants.

Notes: Abstract The history of cochlear implants is marked by large improvements in performance, especially over the past two decades and especially due to the development of ever-better processing strategies. Although the progress to date has been substantial, present devices still do not restore normal speech reception, even for top performers and particularly for listening to speech in competition with noise or other talkers. In addition, a wide range of outcomes persists, with some patients receiving little benefit using the same devices that support high levels of speech reception for others. The purpose of this review is to describe some likely possibilities for further improvement, including (a) combined electric and acoustic stimulation of the auditory system for patients with significant residual hearing, (b) use of bilateral implants, (c) a closer replication with implants of the processing steps in the normal cochlea, and (d) applications of knowledge about factors that are correlated with outcomes to help patients presently at the low end of the performance scale.

Notes: The history of cochlear implants is marked by large improvements in performance, especially over the past two decades and especially due to the development of ever-better processing strategies. Although the progress to date has been substantial, present devices still do not restore normal speech reception, even for top performers and particularly for listening to speech in competition with noise or other talkers. In addition, a wide range of outcomes persists, with some patients receiving little benefit using the same devices that support high levels of speech reception for others. The purpose of this review is to describe some likely possibilities for further improvement, including (a) combined electric and acoustic stimulation of the auditory system for patients with significant residual hearing, (b) use of bilateral implants, (c) a closer replication with implants of the processing steps in the normal cochlea, and (d) applications of knowledge about factors that are correlated with outcomes to help patients presently at the low end of the performance scale.

Notes: The ability of the root system architecture to respond to nutrient availability is a key adaptative behaviour allowing plants to cope with environmental conditions. On the basis of single time point comparisons, the response to phosphate deprivation was previously shown to involve both the primary and lateral roots of Arabidopsis. In this work, the temporal pattern of Arabidopsis root responses to phosphate starvation was investigated. Daily scanning of roots showed that changes in architecture were largely due to the alterations of time-based growth parameters, namely a decrease in the elongation rate of the primary root opposed to an increase in the elongation rate of lateral roots and a decrease in the number of initiated lateral roots. In addition, another identified response was a decrease in the proportion of lateral roots showing early growth arrest. All these changes occurred within a short period of approximately 3 d. In addition, the root morphology comparison with the auxin-resistant mutant axr4, the auxin-treatment of phosphate-starved plants and a limited transcriptome analysis supported the conclusion that auxin signalling was involved in the adaptive response of the root system architecture to phosphate deprivation.

Notes: The root response to changes in nitrogen availability was examined in Arabidopsis thaliana. Plants grown on vertically oriented Petri plates with nutrient media containing either 10 or 0.5 mm KNO3 supplemented with 5 mm glutamine were analysed for changes in root architecture, morphology and nitrogen status compared to plants grown on 0.5 mm KNO3. Fourteen-day-old 10 mm KNO3-grown plants displayed a decrease in number, length and density of lateral roots, had the highest tissue NO3– content, but no change in amino acid composition. Lateral root development was arrested at a stage after the initiation of primordia but prior to emergence. In contrast, plants grown on 0.5 mm KNO3 supplemented with glutamine had a slightly higher number and density of lateral root primordia and lateral roots, lower root NO3– content, and higher tissue glutamine content. A macro-array containing 126 putative A. thaliana transcriptional factor expressed sequence tags was used to screen for regulatory genes with expression correlated to the root plasticity response. Genes for a basic leucine zipper (bZIP) and a LIM transcription factor were identified and via Northern analysis it was confirmed that their expression is preferentially observed in the roots and correlated to the root response to nitrate availability.

Notes: Paraventricular corticotropin-releasing factor (CRF) neurons play a pivotal role in regulating neuroendocrine responses to stress. The mechanisms by which synaptic inputs control the activity of these neurons are not well understood. The present study was undertaken to determine the role of the intrinsic γ-aminobutyric acid (GABA)- and glutamatergic neural circuits of the hypothalamic paraventricular nucleus (PVN) in the control of CRF neural activity. We show that in organotypic cultures of the PVN, blockade of the intrinsic GABAergic neurotransmission by the GABAA receptor antagonist bicuculline resulted in a significant increase in CRF secretion. The bicuculline-induced CRF secretory activity was abolished by the coadministration of the selective α-amino-3-hydroxy-5-methyl-4-isoxazoleprionic acid (AMPA)/kainate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). Electrical stimulation of the CRF cell division elicited glutamatergic extracellular field potentials that were dramatically enhanced by bicuculline and were suppressed by CNQX. These results show that the functional activity of CRF neurons in organotypic cultures of the PVN is under a tonic inhibitory influence of an intrinsic GABAergic circuit. Suppression of GABAergic transmission appears to have a permissive role for inducing an increased secretory activity of CRF neurons that is driven by an excitatory glutamatergic network via AMPA/kainate receptors.

Notes: In the hypoglossal nucleus, GABA and glycine mediate inhibition at separate or mixed synapses containing glycine receptors (GlyRs) and/or GABAA receptors (GABAARs). The functional development of mixed inhibitory synapses depends on the brain area studied, but their relative proportion to total synapses generally decreases with time. We have determined the sequential process of inhibitory synapse maturation in the hypoglossal nucleus in vivo. Immunocytochemistry and confocal microscopy were used for codetection of VIAAT, the common presynaptic vesicular transporter of glycine and GABA, GlyRs, GABAAR α1 and γ2 subunits, and gephyrin, the scaffold protein implicated in the synaptic localization of inhibitory receptors. In E17 embryos, GlyRs were already clustered while GABAAR α1 and γ2 subunit immunoreactivity (IR) displayed both diffuse and clustered patterns. Quantitative analysis at this stage revealed that the majority of GlyR clusters were apposed to VIAAT-IR accumulation and that 30% of them colocalized with γ2GABAAR clusters. This proportion increased with age to 50% at P30. GlyR clusters that did not colocalize with γ2GABAAR clusters were associated with GABAAR γ2 diffuse IR. Interestingly, the percentage of GlyR clusters surrounded by GABAAR γ2 diffuse IR decreased with age, while GlyR clusters colocalized with γ2GABAAR clusters increased. The developmental coclustered pattern of gephyrin and GABAAR α1 and γ2 subunits paralleled the coclustered pattern of GlyRs and GABAAR α1 and γ2 subunits. Our results indicate that the proportion of GlyR-GABAAR coclusters increases until adulthood. A developmental sequence of the postsynaptic events is proposed in which diffuse extrasynaptic GABAARs accumulate at inhibitory synapses to form postsynaptic clusters, most of them being colocalized with GlyR clusters in the adult.

Notes: Abstract  – A stratified epidemiological survey was carried out among the best French rugby players to assess the prevalence of trauma to the lower or middle part of the face (TLMPF) and the frequency at which the mouthguards (MGs) were worn. The 1140 randomized players (elite 1, elite 2 and national 1 clubs) filled in the same form anonymously. The variables were first subjected to univariate analysis (Chi-square, anova). Secondly, they were included in a multivariate model (logistic regression). Some 29.57% of players had already been affected by a TLMPF. The risk increased for the oldest forward players. It also increased with the number of yearly competitions and number of hours of weekly training. Some 64.3% of players used a MG. The frequency at which it was worn increased with the number of yearly competitions, for those who had experinced a previous trauma and for the pack players who had been playing for a long time.