Hydrophilic anchors for transmembrane anion–π slides

The concept of hydrophilic anchoring is introduced to activate rigid oligonaphthalenediimide (O-NDI) rods as anion–π slides for multi-ion hopping across lipid bilayers. We report that short peptide solubilizers suffice to reach the rare combination of high activity and high selectivity that is needed for anion pumping in vesicles.     

Photosensitive post tuning of chalcogenide Te20As30Se50 narrow bandpass filters

We present an experimental study on the photosensitive properties of narrow bandpass filters based on a chalcogenide Te₂₀As₃₀Se₅₀ (TAS) spacer. The transmittance curve of single TAS layer was shifted towards long wavelength direction after 2 h exposure by Xenon arc lamp. The refractive index and extinction coefficient were both increased together with a red shift of optical gap. A maximum 1.7% photo-induced effect was observed. Narrow band filters constituted by TAS and cryolite were manufactured by electron beam deposition. The transmittance spectrum of the filter during the exposure by a wide band source was in situ measured and the resonant wavelength was observed to turn longer gradually till saturation. A spatially localized central wavelength change up to 5.7 nm was finally obtained. The stability of the photo-induced effect was studied and some comments were given at the end of this paper.     

Synthetic multifunctional pores with external and internal active sites for ligand gating and noncompetitive blockage

Design, synthesis, and multifunctionality of p-octiphenyl beta-barrel pores with external LRL triads and internal HH dyads are described. Molecular recognition of anionic fullerenes > calixarenes > pyrenes by guanidinium arrays at the outer pore surface is shown to result in pore opening, whereas alpha-helix recognition within the topologically matching internal space is shown to result in noncompetitive pore blockage. This experimental evidence for multifunctionality is supported by comparison with pertinent control pores and blockers, by structural studies using FRET from p-octiphenyl donors in the pore to BODIPY acceptors in the bilayer, and by molecular mechanics simulations. Practical usefulness of ligand-gated synthetic multifunctional pores is exemplified with the continuous detection of chemical processes.     

The Voice Handicap Index: Correlation Between Subjective Patient Response and Quantitative Assessment of Voice

The aim of this prospective study is to elucidate the relationship between the Voice Handicap Index (VHI) and several voice laboratory measurements in the network of the multidimensional voice assessment. Fifty-eight patients were included. Each patient replies to the questionnaire and performs a voice assessment during the same time. The following parameters were measured: minimum frequency, maximum frequency, range, minimum intensity, subglottic pressure, mean flow, maximum phonation time, jitter, and dysphonia severity index. Regarding the relationship with the scores of the VHI, poor correlations with the minimal frequency for all the scores except the emotional one (total and subscales) and with the range for only the physical one are found. Seventeen questions correlate with the voice laboratory measurements we performed, with a decreased distribution between physical, functional, and emotional subscales. We observe that acoustic parameter is correlated with the emotional subscale, the parameters of the profile range are more often involved in the emotional subscale, as is the minimal frequency, but never with the physical subscale, and all the subscales are interesting despite the smaller number of differences with the emotional one. The VHI and the laboratory measurements give independent informations in practice.     

Photoacoustic spectroscopy for trace gas detection with cryogenic and room-temperature continuous-wave quantum cascade lasers

The main characteristics that a sensor must possess for trace gas detection and pollution monitoring are high sensitivity, high selectivity and the capability to perform in situ measurements. The photacoustic Helmholtz sensor developed in Reims, used in conjunction with powerful Quantum Cascade Lasers (QCLs), fulfils all these requirements. The best cell response is # 1200 V W⁻¹ cm and the corresponding ultimate sensitivity is j 3.3 × 10⁻¹⁰ W cm⁻¹¹ Hz^−11/2. This efficient sensor is used with mid-infrared QCLs from Alpes Lasers to reach the strong fundamental absorption bands of some atmospheric gases. A first cryogenic QCL emitting at 7.9 μm demonstrates the detection of methane in air with a detection limit of 3 ppb. A detection limit of 20 ppb of NO in air is demonstrated using another cryogenic QCL emitting in the 5.4 μm region. Real in-situ measurements can be achieved only with room-temperature QCLs. A room-temperature QCL emitting in the 7.9 μm region demonstrates the simultaneous detection of methane and nitrous oxide in air (17 and 7 ppb detection limit, respectively). All these reliable measurements allow the estimated detection limit for various atmospheric gases using quantum cascade lasers to be obtained. Each gas absorbing in the infrared may be detected at a detection limit in the ppb or low-ppb range.     

Red Wine Extract Inhibits VEGF Secretion and Its Signaling Pathway in Retinal ARPE-19 Cells to Potentially Disrupt AMD

Age-related macular degeneration (AMD) is a degenerative disease of the retina where the molecular mechanism involves the production of vascular endothelial growth factor (VEGF), a factor of poor prognosis of the progression of the disease. Previous studies have shown that resveratrol, a polyphenol of grapevines, can prevent VEGF secretion induced by stress from retinal cells. Considering the fundamental role played by VEGF in development and progression of AMD, we investigate the potential effect of red wine extract (RWE) on VEGF secretion and its signaling pathway in human retinal cells ARPE-19. To examine the effect of RWE in ARPE-19, a quantitative and qualitative analysis of the RWE was performed by HPLC MS/MS. We show for the first time that RWE decreased VEGF-A secretion from ARPE-19 cells and its protein expression in concentration-dependent manner. RWE-induced alteration in VEGF-A production is associated with a down of VEGF-receptor 2 (VEGF-R2) protein expression and its phosphorylated intracytoplasmic domain. Subsequently, the activation of kinase pathway is disturbing and RWE prevents the phosphorylation of MEK and ERK 1/2 in human retinal cells ARPE-19. Finally, this study sheds light on the interest that the use of polyphenolic cocktails could represent in a prevention strategy.     

Free-radical carboalkynylation and carboalkenylation of olefins

Free-radical three-component carboalkynylation and -alkenylation of olefins have been developed. These involve the addition, across the double bond of an unactivated olefin, of a radical species α- to an electron-withdrawing group and an alkenyl or alkynyl moiety, derived from the corresponding sulfones.     

New Bimetallics of Mo and W with Metallocene,Metal Carbonyl and Bridging PPh2 or ‘Cp’PPh2 Units

Ring substituted (R=^tBu, SiMe₃) metallocene dichlorides undergo a nucleophilic substitution on one of the two rings upon the action of LiPPh₂M'(CO)_x salts with the formation of chloro-hydrido complexes [C₅H₃(R)PPh₂M'(CO)_x](C₅H₄R)M(H)Cl. Their UV irradiation leads to the chloro-bridged M(μ-Cl)M' separable diastereoisomers. Use of the ansa-metal-locene dichlorides [Me₂X(C₅H₄)₂MCl₂] (X=Si or C) allowed the access to the new bridging system [M(μ-PPh₂, μ-Cl)M′] (M=Mo, W ; M'=W).