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Molecular fluorescence is a phenomenon that is usually observed in condensed phase. It is strongly affected by molecular interactions. The study of fluorescence spectra in gas-phase can provide a nearly ideal model for the evaluation of the intrinsic properties of fluorophores. Unfortunately, most conventional fluorophores are not volatile enough to allow for the study of their fluorescence in gas phase. Here we report very bright gas phase fluorescence of simple BODIPY dyes that can be readily observed at atmospheric pressure using conventional fluorescence instrumentation. To our knowledge, this is the first example of visible-range gas-phase fluorescence at near-ambient conditions. Evaporation of the dye in vacuum allowed us to demonstrate organic molecular electroluminescence in gas discharge excited by the electric field produced by a Tesla coil. • Low molecular weight BODIPY dyes are shown to exhibit bright visible fluorescence in gas phase when slightly heated at atmospheric pressure, or put into vacuum. • The combination of bright fluorescence and high volatility, caused by low molecular weight and zero net charge, makes these fluorophores unique. • The fluorescence in gas phase is blue shifted, exhibits smaller Stokes shift and increased lifetime. • The spectra of gas-phase molecules devoid of solvation effects can be used to validate quantum chemical computations of molecular excited states. [ABSTRACT FROM AUTHOR]

Abstract To study protons localization in H 1.83 K 0.17 La 2 Ti 3 O 10 ·0.17H 2 O and their motional characteristics, complementary Nuclear Magnetic Resonance (NMR) techniques have been applied. 1H Magic Angle Spinning NMR evidences the presence of different proton containing species. By analyzing the temperature dependence of the 1H MAS NMR spectrum we attribute the observed lines to interlayer H+ in regular sites (isolated and in water rich environment), water protons and protons from various defects. The temperature behaviors of the spectral lines intensities and widths point out that intercalated water molecules are involved in translational motion that is confirmed by spin lattice relaxation rate (R 1) and spin-lattice relaxation rate in rotating frame (R 1 ρ) measurements. It has been shown that for a correct determination of the proton motional parameters the Kohlrausch-Williams-Watts correlation function must be used. Its application results in the following parameters of proton motion in the interlayer space of H 1.83 K 0.17 La 2 Ti 3 O 10 ·0.17H 2 O: E a = 0.194(2) eV, β = 0.28(1), τ 0 = 6.2 (1) × 10 − 10 s. [ABSTRACT FROM AUTHOR]

Abstract: Despite the availability of effective antihypertensive therapies, adherence to and persistence with treatment is suboptimal. As such, there is a need to better understand factors associated with adherence and persistence, such as race/ethnicity. In a retrospective, exploratory analysis of 51,772 hypertensive adult subjects identified in the electronic medical record, we examined medication possession ratio and proportion of days covered as proxies for adherence and persistence, respectively. Logistic regression analyses were performed to assess the role of race/ethnicity in adherence to and persistence with antihypertensive treatments. Relative to white subjects, Asian American/Pacific Islander, black, Hispanic, and “other” subjects were significantly less likely to be adherent to and persistent with their antihypertensive regimens. Black and Hispanic subjects had the lowest odds of adherence (0.46, 95% CI: 0.43–0.49 and 0.58, 95% CI: 0.54–0.62, respectively) and persistence (0.70, 95% CI: 0.65–0.75 and 0.70, 95% CI: 0.66–0.74, respectively) relative to white subjects. Other factors significantly associated with both lower adherence and persistence included younger age and lower chronic disease score. Disparities were found with regard to adherence to and persistence with antihypertensive regimens. Future studies should address these disparities by designing interventions to improve medication-taking behavior in high-risk populations. [Copyright &y& Elsevier]

The increased cardiovascular risk associated with hypertriglyceridemia is thought to be due in part to high levels of triglyceride (TG)-rich lipoproteins and small dense low-density lipoprotein (LDL). In this post hoc analysis, effects of increasing doses of atorvastatin (10, 20, 40, and 80 mg) on atherogenic lipid subclasses commonly associated with hypertriglyceridemia were evaluated in 191 men and women who were candidates for lipid-lowering therapy and had baseline TG levels >200 mg/dl (2.3 mmol/L). After 8 weeks of treatment, in addition to significantly decreasing LDL cholesterol and TG levels, atorvastatin significantly increased LDL peak particle diameter (p <0.01) and significantly decreased the concentration of small LDL subclasses IIIa and IIIb (p <0.0001) from baseline at all doses. These effects were more pronounced with higher compared with lower doses of atorvastatin. Each dose of atorvastatin also significantly lowered levels of very LDL, intermediate-density lipoprotein (p <0.0001), and small very LDL subclass 3 (p <0.0001). Greater decreases were achieved by those patients receiving higher doses of atorvastatin (20, 40, and 80 mg). The increase in LDL size correlated with the decrease in TG levels, but not with the decrease in LDL cholesterol levels. However, the decrease in small dense LDL cholesterol concentrations correlated significantly with TG and LDL cholesterol decreases. In conclusion, atorvastatin significantly lowered levels of TG-rich remnant lipoproteins and favorably changed LDL particle size in patients with hypertriglyceridemia. These effects may explain the benefits of statin therapy in high-risk patients with hypertriglyceridemia even when levels of LDL cholesterol are at goal. [Copyright &y& Elsevier]

Abstract: Two isomers of the hexahydro-tetraazaacenaphthylene templates (1 and 2) are presented as novel, potent, and selective corticotropin releasing factor-1 (CRF1) receptor antagonists. In this paper, we report the affinity and SAR of a series of compounds, as well as pharmacokinetic characterization of a chosen set. The anxiolitic activity of a selected example (2ba) in the rat pup vocalization model is also presented. [Copyright &y& Elsevier]

The present work reports an overview of the main results we have obtained from non-conventional sintering approaches towards the densification of 3mol.% yttria stabilized zirconia (3YSZ), the lessons learned from these results, and open questions that still need to be addressed. A wide range of techniques have been developed in the field of ceramic sintering, both in high temperature regime with extreme heating rates (>10 000 °C/min), as well as in very low temperatures (<400 °C) regime involving chemical reactivity to activate sintering mechanisms. In this context, we have recently explored several of these methods in order to understand and control the different sintering parameters and their impact on microstructure, crystallinity, grain boundaries and defect chemistry. Due to its complex chemistry, 3YSZ is a playground for the exploration of sintering capabilities and their influence on ceramic properties. Our recent studies in this field are presented in the present work, highlighting the effect of high heating rates through Flash Spark Plasma Sintering (Flash-SPS) and Ultra High temperature Sintering (UHS) on sintering, but also the combination of low temperature Cold Sintering Process (CSP) and the associated precursors chemistry, with Spark Plasma Sintering (SPS). It also shows the possible densification by reactive hydrothermal sintering, using hydroxide precursors, and the effect of High Pressure SPS (HP-SPS) on 3YSZ nanopowders. All of these results touch upon current trends in the field of sintering, and highlight the possibilities in terms of chemical reactivity of precursors and physical parameter control. In particular, they show the importance of defect chemistry, related to the sintering atmospheres and their impact on both microstructures and properties. [ABSTRACT FROM AUTHOR]

• Inactivated E. coli expressing HcBoNT/C and D are safe and effective in cattle. • Recombinant bacterin is a low-cost alternative process for botulism prevention. • Recombinant bacterin induce high levels of neutralizing antibodies in cattle. Botulism is a paralytic disease caused by the intoxication of neurotoxins produced by Clostridium botulinum. Among the seven immunologically distinct serotypes of neurotoxins (BoNTs A − G), serotypes C and D, or a chimeric fusion termed C/D or D/C, are responsible for animal botulism. The most effective way to prevent botulism in cattle is through vaccination; however, the commercially available vaccines produced by detoxification of native neurotoxins are time-consuming and hazardous. To overcome these drawbacks, a non-toxic recombinant vaccine was developed as an alternative. In this study, the recombinant protein vaccine was produced using an Escherichia coli cell-based system. The formaldehyde-inactivated E. coli is able to induce 7.45 ± 1.77 and 6.6 ± 1.28 IU/mL neutralizing mean titers against BoNTs C and D in cattle, respectively, determined by mouse neutralization bioassay, and was deemed protective by the Brazilian legislation. Moreover, when the levels of anti-BoNT/C and D were compared with those achieved by the recombinant purified vaccines, no significant statistical difference was observed. Cattle vaccinated with the commercial vaccine developed 1.33 and 3.33 IU/mL neutralizing mean titers against BoNT serotypes C and D, respectively. To the best of our knowledge, this study is the first report on recombinant E. coli bacterin vaccine against botulism. The vaccine was safe and effective in generating protective antibodies and, thus, represents an industry-friendly alternative for the prevention of cattle botulism. [ABSTRACT FROM AUTHOR]

Unique derivatives of androstene and estrane series containing N -sulfonylimidate pendants were prepared from 17 α -ethynyl steroids via Cu-catalyzed azide–alkyne cycloaddition to tosyl azide in the presence of alcohols. The synthesized compounds were screened for cytotoxicity against human breast cancer cell lines and ERα agonist activity. The hit compound 3,17 β -dimethoxy-17 α -[ iso -propyl-2′- N -tosylacetimidate]estra-1,3,5(10)-triene (4n) had no ERα-mediated hormonal activity and was found to exhibit potent cytotoxic effect in an ERα-positive breast cancer cell line. N -Sulfonylimidate 4n displayed high antiproliferative potency against triple-negative MDA-MB-231 breast cancer cells, while it was non-toxic towards normal mammary epithelial cells. Compound 4n was found to alter activity of various signaling pathways (NF-κB, Slug, cyclin D1, ERK) supporting the growth and invasiveness of tumor cells. Image 1 • A broad series of novel steroidal N -sulfonylimidates were prepared and screened for activity against breast cancer cells. • Hit compound 4n showed no agonist activity against ERα and exhibited high antiproliferative activity against breast cancer cells. • The structure–activity relationship data for steroidal N -sulfonylimidates are summarized. • Hit compound 4n proved to be active against triple-negative MDA-MB-231 breast cancer cells and non-toxic in MCF-10A cells. • Hit compound 4n altered activity of various signaling pathways (NF-κB, Slug, cyclin D1, ERK). [ABSTRACT FROM AUTHOR]

We report herein the design, synthesis and biological evaluation of series of 7-substituted fluoroquinolones with pyridoxine derivatives. In vitro screening of antibacterial activity and toxicity of 39 synthesized fluoroquinolones defined compounds 7 and 28 as lead compounds for further investigations. On various clinical isolates lead compounds 7 and 28 exhibited antibacterial activity comparable with reference fluoroqinolones. Mutagenic effects haven't been observed for these compounds in SOS-chromotest. Compound 7 are non-toxic in vivo on mice (LD 50 > 2000 mg/kg, oral) and rats (LD 50 > 2000 mg/kg, oral). Compound 28 was more toxic (LD 50 = 474 mg/kg, oral, mice). Moreover compound 7 showed greater in vivo efficacy compared to ciprofloxacin in a murine model of staphylococcal sepsis. Taken together the described active compound are promising candidate for preclinical trials. [Display omitted] • Synthesis and biological evaluation of fluoroquinolones containing a pyridoxine derivatives moiety • The compounds exhibited in vitro promising antibacterial activity against Gram-positive and Gram-negative bacterial strains. • Lead compound 7 is non-toxic in vivo on mice (LD 50 > 2000 mg/kg, oral) and rats (LD 50 > 2000 mg/kg, oral) and showed greater in vivo efficacy compared to ciprofloxacin in a murine model of staphylococcal sepsis. [ABSTRACT FROM AUTHOR]

• Long-chain alkenone distributions can be used as a proxy of salinity. • Unsaturation indexes U 40 K and U 40 K ′ are positively correlated with salinity. • Haptophytes of Group 2 dominate in the studied Siberian lakes. • The alkenone compositions are similar to other semi-arid temperate regions. Long-chain alkenones (LCAs) are polyunsaturated methyl or ethyl ketones exclusively produced by Groups 1–3 Isochrysidales, an order of haptophyte algae. LCAs have great potential as temperature and salinity proxies for paleo-reconstructions. Alkenone producers occur extensively in lacustrine and in open marine systems. However, factors influencing LCAs occurrence, abundance, compositional pattern, and unsaturation indices are insufficiently understood in lakes of southern Siberia. Here we investigated alkenone distributions in freshwater to saline lakes of a semi-arid region of southern Siberia (n = 22). We find that total alkenone concentrations increase dramatically above a salinity of about 20 g L−1. Analysis of 18S rRNA and the alkenone composition suggest that all alkenone-containing lakes are inhabited by Group 2 haptophytes except one low-saline lake, where Group 1 representatives prevail. The C 37 /C 38 ratio is negatively correlated with salinity, and, hence, this parameter can be used as a salinity indicator. At the same time, %C 37:4 is not correlated with salinity, whereas the average chain length of alkenones increases with salinity. The taxonomic composition of haptophytes and the alkenone composition were comparable to those in the lakes in the Canadian Prairies, potentially because of the similarities in climatic factors and ionic composition of lake water in the two regions. This study shows for the first time that unsaturation indexes U 40 K and U 40 K ′ are positively correlated with salinity and, thus, can be used as a salinity proxy for regional climate reconstruction. [ABSTRACT FROM AUTHOR]

Abstract: The interest in organic materials for use in organic light-emitting diodes (OLEDs) began with the pioneering report of efficient green electroluminescence from Alq3, tris(quinolin-8-olato)aluminum(III), by Tang and Van Slyke [C.W. Tang, S.A. Van Slyke, Appl. Phys. Lett. 51 (1987) 913]. After more than 20 years of intense research and development in OLEDs, Alq3 continues to be a widely used electroluminescent material in OLED technology. Alq3 is used in the electron-transport and/or electron-injecting layer in multilayer device structures and also as an effective host material for various dyes. Much is known about the properties of this metal chelate complex, yet much remains unknown despite numerous studies. In recent years, five crystalline phases (α, β, γ, δ, and ε) of Alq3 have been identified. In the present report, a combined structural, thermal, and spectroscopic (Raman, fluorescence, and nuclear magnetic resonance) analysis of different crystalline phases of Alq3 is presented. [Copyright &y& Elsevier]

A diverse series of 43 novel "soft antimicrobials" based on quaternary ammonium pyridoxine derivatives which include six-membered acetals and ketals of pyridoxine bound via cleavable linker moieties (amide, ester) with a fragment of fatty carboxylic acid was designed. Nine compounds exhibited in vitro promising antibacterial activity against Gram-positive and Gram-negative bacterial strains with MIC values comparable with reference antiseptics miramistin, benzalkonium chloride and chlorohexidine. On various clinical isolates, the lead compounds 6i and 12a exhibited antibacterial activity comparable with that of benzalkonium chloride while higher than that of miramistin. Moreover, 6i and 12a were able to kill bacteria embedded into the matrix of mono- and dual species biofilms. The treatment of bacterial cells by either 6i and 12a lead to fast depolarization of the membrane suggesting that the membrane is an apparent molecular target of compounds. 6i and 12a were non mutagenic neither in SOS-chromotest nor in Ames test and non-toxic in vivo at acute oral (LD 50 > 2000 mg/kg) and cutaneous administration (LD 50 > 2500 mg/kg) on mice. Taken together, our data allow suggesting described active compounds as promising starting point for the new antibacterial agents development. Image 1 • Design and synthesis of novel "soft antimicrobials" based on quaternary ammonium pyridoxine derivatives. • The compounds exhibited in vitro promising antibacterial activity against Gram-positive and Gram-negative bacterial strains. • Lead compounds 6i and 12a exhibited promising antibacterial activity on clinical isolates and bacterial biofilms. • Lead compounds 6i and 12a were non mutagenic neither in SOS-chromotest nor in Ames test and non-toxic in vivo. [ABSTRACT FROM AUTHOR]