Abcès hypophysaire chez un hémodialysé chronique traité médicalement : à propos d’une observation

L’abcès hypophysaire est une pathologie rare et fatale en absence de traitement adéquat .Il est à évoquer devant un tableau clinique  d’hypertension intracrânienne, une dysrégulation hormonale hypophysaire et un contexte infectieux. Une conduite thérapeutique basée sur une  antibiothérapie pourrait être tenté si diagnostic précoce. Nous rapportons un cas d’abcès hypophysaire survenant chez un hémodialysé chronique pris en charge par une antibiothérapie seule dont l’évolution était favorable avec un recul de 2 ans

Towards a biosensor based on Anti Resonant Reflecting Optical Waveguide fabricated from porous silicon.

International audienceRecently, we demonstrated that Anti Resonant Reflecting Optical Waveguide (ARROW) based on porous silicon (PS) material can be used as a transducer for the development of a new optical biosensor. Compared to a conventional biosensor waveguide based on evanescent waves, the ARROW structure is designed to allow a better overlap between the propagated optical field and the molecules infiltrated in the porous core layer and so to provide better molecular interactions sensitivity. The aim of this work is to investigate the operating mode of an optical biosensor using the ARROW structure. We reported here an extensive study where the antiresonance conditions were adjusted just before the grafting of the studied molecules for a given refractive index range. The interesting feature of the studied ARROW structure is that it is elaborated from the same material which is the porous silicon obtained via a single electrochemical anodization process. After oxidation and preparation of the inner surface of porous silicon by a chemical functionalization process, bovine serum albumin (BSA) molecules, were attached essentially in the upper layer. Simulation study indicates that the proposed sensor works at the refractive index values ranging from 1.3560 to 1.3655. The experimental optical detection of the biomolecules was obtained through the modification of the propagated optical field and losses. The results indicated that the optical attenuation decreases after biomolecules attachment, corresponding to a refractive index change Δnc of the core. This reduction was of about 2 dB/cm and 3 dB/cm for Transverse Electric (TE) and Transverse Magnetic (TM) polarizations respectively. Moreover, at the detection step, the optical field was almost located inside the core layer. This result was in good agreement with the simulated near field profiles

Rich polymorphism of a rod-like liquid crystal (8CB) confined in two types of unidirectional nanopores

We present a neutron and X-rays scattering study of the phase transitions of 4-n-octyl-4'-cyanobiphenyl (8CB) confined in unidirectional nanopores of porous alumina and porous silicon (PSi) membranes with an average diameter of 30 nm. Spatial confinement reveals a rich polymorphism, with at least four different low temperature phases in addition to the smectic A phase. The structural study as a function of thermal treatments and conditions of spatial confinement allows us to get insights into the formation of these phases and their relative stability. It gives the first description of the complete phase behavior of 8CB confined in PSi and provides a direct comparison with results obtained in bulk conditions and in similar geometric conditions of confinement but with reduced quenched disorder effects using alumina anopore membranesComment: Accepted in EPJ E - Soft Matte

M004 In aortic stenosis, 2D speckle tracking differentiates left ventricular dysfunction load- to remodelling-dependant

BackgroundIn aortic stenosis, it is not known which between longitudinal, radial and circumferential contraction is influenced by loading conditions or remodelling. To test our hypothesis and to understand left ventricular function recovery, we investigated patients at early, i.e. 7 days (contractility enhancement load-dependant) and at late follow-up, i.e. 3 months (contractility enhancement remodelling-dependant) after transcutaneous aortic valve implantation (TAVI).Methods and ResultsTwenty-three subjects (AS: valve orifice < or =0.7cm2; 14 female; mean age, 84+/-6 years) were studied. All subjects of the study had conventional 2D-Doppler echocardiography and speckle tracking analysis (GE HealthCare). Speckle tracking was sampled in short-axis view for radial and circumferential strain and in apical 4, 3 and 2-chamber view for averaged longitudinal strain. Measurements were performed before, 7 days and 3 months after TAVI. Mean pressure gradient decreased from 41±20mmHg to 10±3mmHg (p<0.001) while aortic valve area increased from 0.6±0.1 to 1.7±0.2cm2 (p<0.001) after implantation. Biplane Simpson EF was 50±10 %, 51±13 and 58±11 % at baseline, 7-day and 3-month follow-up (p=0.01), respectively. Improvement of circumferential strain found 7 days after TAVI is sustained at 3 months. Radial strain increased shortly after TAVI, then decreased at 3 months and was compensated by improvement of longitudinal strain (see figure).ConclusionIn patients with aortic stenosis, radial contraction is load dependant, circumferential contraction is both load- and remodelling-dependant, whereas longitudinal contraction is remodeling-dependant

Canopy Temperature Efficiency as Indicators for Drought Tolerance in Durum Wheat (Triticum Durum Desf.) in Semi Arid Conditions

Durum wheat (Triticum durum Desf.) is one of the more widely cultivated crops in the Mediterranean basin, where drought is the main abiotic stress limiting its production. This study was conducted on the experimental site of station ITGC in Setif, Algeria. The objectives of this study were (i) to determine differences in canopy temperature (CT) and canopy temperature depression (CTD) of different durum wheat under both well-watered and moisture stressed conditions and (ii) to correlate canopy temperature (CT) and canopy temperature depression (CTD) with drought resistance indices value and yield of durum wheat (Triticum durum Desf.) under both conditions. The results of study showed a significant difference between CT and CTD under both conditions and among genotypes. Under dryland conditions, grain yield and mean CTD were correlated positively (r = 0.32**), this correlation is similar to other studies (Blum et al., 1989; Royo et al., 2002). Similar results of correlation between canopy temperature (CT), canopy temperature depression (CTD) and grain yield suggest that the use of CT and CTD in screening for highly tolerant varieties to drought is similar. The significant correlation of CT and CTD with Mean productivity (MP) and Stress tolerance index (STI) suggests that CTD and/or CT can be favorite selection criteria in plant breeding for drought tolerance

Relationship between Flag Leaf Reflectance and Canopy Temperature in Durum Wheat (Triticum durum Desf.) Cultivars under Stressed and Irrigated Conditions

Optical technologies can be developed as practical tools for monitoring plant health by providing unique spectral signatures that can be related to specific plant stresses. The objectives of this study were (i) to determine differences in canopy temperature and leaf reflectance of different durum wheat under both well-watered and moisture stressed conditions and (ii) evaluate the relationships between canopy temperature and leaf reflectance at Red and Blue (RB) wavelength. We use numerical image analysis by Mesurim Pro (Version 3.3) softwarefor estimate leaf reflectance at Red and Blue (RB) wavelength.In this study irrigation treatments affect significantly flag leaf reflectance at RB and canopy temperature. Significant correlations were registered between leaf reflectance and canopy temperature under both conditions irrigated and non irrigated; these best correlations proved the efficiency of using leaf reflectance at RB in screening for drought tolerance in durum wheat cultivars