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The present work reports a method for green synthesis of silver nanoparticles (AgNPs) by reducing Ag ions from silver nitrate solution using alcoholic, aqueous and alcoholic-aqueous Stevia rebaudiana extracts. Depending on a particular extract different sizes of AgNPs could be observed – 40 nm in aqueous and aqueous-alcoholic extracts and significantly bigger 170 nm in case of alcoholic extract. Synthesis of AgNPs was analyzed within spectra range of 300–700 nm. The performed research provided information that aqueous and aqueous-alcoholic extracts are excellent sources for synthesis of AgNPs; however AgNPs were unstable in the case of alcoholic extract. The aqueous-alcoholic extract showed the best properties during studies. Antioxidant potential, antimicrobial properties and cytotoxicity were determined. The 2,2-diphenyl-1-(2,4,6-triphenyl-hydrazyl) method showed that antioxidant activity of an extract containing AgNPs was higher compared to Stevia extract alone. Bacterial inhibition studies had...

Dynamic crossover above Tg has been recognized as a characteristic feature of molecular dynamics of liquids approaching glass transition. Experimentally, it is manifested as a change in Vogel–Fulcher–Tammann dependence or a breakdown of the Stokes–Einstein and related relations. In this paper, we report the exception from this rather general pattern of behavior. By means of dielectric, ultrasonic, rheological, and calorimetric methods, dynamics of two good ionic conductors (BMIm)2[Co(NCS)4] and (EMIm)2[Co(NCS)4] of less common stoichiometry (2:1) was studied in a very broad temperature range. However, none of the mentioned dynamic changes was observed in the entire studied temperature range. On the contrary, the single VFT and the same fractional Walden coefficient were found for conductivity and viscosity changes over 12 decades. Moreover, ultrasonic studies revealed that the data at temperatures which cover the normal liquid region cannot be fitted by a single exponential decay, and the Cole–Cole functi...

Summary This study presents the effect of heat treatment of chickpea seeds on biological activity of peptides obtained by in vitro gastrointestinal digestion. The most significant antiradical activity against ABTS+• expressed as IC50 value was observed for 3.5- to 7-kDa peptide fraction from TC hydrolysate (41.01 μg mL−1). In turn, peptide fraction of 3.5–7.0 kDa obtained from raw chickpea seeds hydrolysate showed the highest antiradical activity against DPPH• and Fe2+ chelating activity with IC50 value of 20.94 and 52.53 μg mL−1, respectively. The highest Cu2+ chelating activity was observed for peptides obtained from TC hydrolysate (IC50 = 56.60 μg mL−1). Peptide fraction

The aim of the presented study was to characterize the content and biological activity of extracts prepared from dried Stevia rebaudiana leaves with potential application in the food or cosmetic industry. Aqueous (A), ethanolic (E) and glycol-aqueous (GA) extracts were analyzed for the content of polyphenols and proteins, showing that the highest amount of phenols (15.50 mg/g) and flavonoids (3.85 mg/g) contained GA. All extracts contained significant amount of protein (69.40-374.67 mg/g). Between analyzed stevia extracts (HPLC) GA contained the highest amount of polyphenols, especially ferulic (5.50 mg/g) and rozmaric (4.95 mg/g) acids derivates. The highest antiradical activity against DPPH• and ABTS•+ was noted for GA and E (IC50 = 0.38 and 0.71 µg flavonoids/mL). The highest ability to chelate Fe2+ was observed for E (IC50 = 2.08 µg flavonoids/mL). Stevia extracts were also analyzed for their cytotoxicity and fibroblast irritation potential in vitro. E and GA were the most cytotoxic and irritating, probably due to the high content of biologically active phytochemicals. On the other hand, a extract was the most tolerable by the cells. To summarize, the presented study evaluated the potential application of A, E and GA stevia extracts as natural source of antioxidants in the food and cosmetic industry.

International audience; Understanding the effect of liquid viscosity in nanoconfinement is of paramount importance from both the fundamental and practical points of view. In particular, unexpected dynamic phenomena are ubiquitous in a broad range of nanofluidic applications. In this work, we used state-of-the-art high-pressure (P,V,T) calorimetry for direct observation of pressure, volume, temperature, and thermal effects during controlled intrusion/extrusion of liquids in nanoporous materials. It was discovered that the liquid extrusion pressure and the accompanying thermal effects can be controlled by changing solely the liquid viscosity. Such knowledge allowed us to propose the {nanoporous material + nonwetting liquid} system as a self-recovering nanobumper and to clarify the parameters for its optimization. Experimental results were interpreted in terms of confined classical nucleation theory as the slowdown of bubble expansion in the nanopores because of the high liquid viscosity. The present results are of practical value for designing energy storage/dissipation devices based on intrusion/extrusion cycles, as well as of fundamental importance for understanding the effect of viscosity in nanoconfined liquids.

International audience; A complete review of the literature data on the speed of sound and ultrasound absorption in pure ionic liquids (ILs) is presented. Apart of the analysis of data published to date, the significance of the speed of sound in ILs is regarded. An analysis of experimental methods described in the literature to determine the speed of sound in ILs as a function of temperature and pressure is reported, and the relevance of ultrasound absorption in acoustic investigations is discussed. Careful attention was paid to highlight possible artifacts, and side phenomena related to the absorption and relaxation present in such measurements. Then, an overview of existing data is depicted to describe the temperature and pressure dependences on the speed of sound in ILs, as well as the impact of impurities in ILs on this property. A relation between ions structure and speeds of sound is presented by highlighting existing correlation and evaluative methods described in the literature. Importantly, a critical analysis of speeds of sound in ILs vs those in classical molecular solvents is presented to compare these two classes of compounds. The last part presents the importance of acoustic investigations for chemical engineering design and possible industrial applications of ILs.

(p,ρ,T) data of ionic liquid 1-butyl-3-methylimidazolium acetate [BMIM][AC] at T = (273.15–413.15) K and pressures up to p = 140 MPa are reported with an estimated experimental relative combined standard uncertainty of Δρ/ρ = ±(0.01–0.08)% in density. The density at different temperatures and under high pressures, ρ(p,T), was determined by means of high pressure–high temperature Anton-Paar DMA HMP vibrating tube densimeter. The viscosity correction (ρHPM − ρ)/ρHPM is included in the density measurements according to literature suggestion. Density ρ, at ambient pressure was additionally measured using Anton Paar densimeter DMA 5000. Dynamic viscosity, η, was measured using Anton Paar SVM 3000 Stabinger viscometer with the reproducibility in 0.35%. The isobaric heat capacity cp, was measured using Pyris 1 diamond differential scanning calorimeter. The standard uncertainty is around 1% for temperatures excluding lower values (around T = 273.15 K), where δcp/cp reaches 3%. Surface tension, σ, was measured using pendant drop method with drop shape analysis system DSA 100 (Kruss GmbH). The uncertainty of the surface tension measurements was Δσ = ±0.1 mN m−1. An empiric equation of state for fitting of the (p,ρ,T) data of [BMIM][AC] has been developed as a function of pressure and temperature. This equation is used for fitting of the experimental results and also for the calculation of the thermophysical properties of IL, such as isothermal compressibility, isobaric thermal expansibility, thermal pressure coefficient, internal pressure, isobaric and isochoric heat capacities, speed of sound and is entropic exponent.

Speeds of sound and densities of binary mixtures of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide with acetonitrile or with tetrahydrofuran have been measured within the temperature range of (298.15 to 313.15) K. From these experimental values, some related quantities have been derived, such as adiabatic compressibility coefficients, κs, excess molar volumes, VE, excess molar compressions, KSE, apparent molar volumes, Vϕ, partial molar volumes, Vi, excess partial molar volumes, ViE, and apparent molar adiabatic compressions, KS,ϕ. It has been found that concentration dependence of speed of sound in investigated systems resembles that of surface tension. Also, it has been observed that excess molar volumes and adiabatic compressions of some shorter chain 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imides in mixtures with the same solvent are very similar.

Hirschsprung disease (HD) is a congenital malformation defined as the absence of myenteric and submucosal ganglion cells (GCs) in the distal rectum and variable length of the contiguous bowel. The aim of this study was to assess the utility of calretinin immunochemistry in comparison with that of standard histology complemented with acetylcholinesterase (AChE) histochemistry routinely employed at our institution to evaluate rectal biopsies carried out for suspicion of HD. Twenty-one rectal biopsies were reviewed, including 14 from patients with suspected HD, 6 from infants with necrotizing enterocolitis (NEC), and 1 from a patient diagnosed with spontaneous intestinal perforation (SIP). Sections stained with hematoxylin-eosin (HE) revealed absence of ganglion cells in 13 cases which included 11 patients with HD and 2 patients with NEC. Among 13 cases of aganglionosis the AChE reaction pattern was consistent with HD in 2 patients. Calretinin positivity was observed in all rectal biopsies showing the presence of GC, and the staining was consistently absent in all cases of aganglionosis. In 6 rectal biopsies in which abnormal acetylcholinesterase (AChE) staining was not seen, loss of calretinin immunoreactivity helped establish the diagnosis of HD.

The speed of ultrasound measurements in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [EMIm][NTf2], were performed in the temperature range from (288 to 318) K and at pressures from (15 to 101) MPa. The speeds of ultrasound, densities, and isobaric heat capacities have been determined at ambient pressure for temperatures from (287 to 323) K, (278.15 to 363.15) K, and (293.15 to 323.15) K, respectively. The pressure dependence of densities and adiabatic compressibilities were calculated using the speeds of ultrasound at high pressure as well as densities and heat capacities at ambient pressure. The experimental densities reported in the literature are in a good agreement with the densities calculated in this work.

An anamorphic Bjerkandera adusta CCBAS 930 strain isolated from soil was found to decolorize two anthraquinonic dyes: Remazol Brilliant Blue R and Poly R-478. The reduction in the level of phenolic compounds in liquid B. adusta cultures containing RBBR and Poly R-478 was correlated with decolorization of studied dyes, which suggested their biodegradation. It was shown that this process was coupled with induction of secondary metabolism (idiophase) and peak peroxidase activity in culture medium, and the appearance of aerial mycelium. Decolorization of dyes depended on the presence of glucose (cometabolism).

The liquid–liquid equilibria of two binary systems containing 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide with butan-1-ol or hexan-1-ol at atmospheric pressure have been investigated. The two-phase line was observed as function of temperature using light scattering or visual detection. In addition, other physical properties such as the densities of phases in equilibrium and the interfacial tension were determined. The results obtained were compared with the literature and briefly discussed in terms of possible interactions that may occur in ionic liquid + alkan-1-ol solutions.

The triple association between juvenile xanthogranuloma (JXG), juvenile myelomonocytic leukemia and neurofibromatosis was described in literature in about 20 cases. In this paper, the case of an 11-month-old infant boy with a disseminated JXG with unusual cytogenetic representation in the bone marrow was reported. Neurofibromatosis and juvenile myelomonocytic leukemia were excluded, just the same as other leukemias. Bone marrow and peripheral blood cytogenetic analysis revealed a karyotype with many rearrangements 46,XY,-6,der(12)t(6;12)(p21;p13),del(7)(p13p22),+9 once described in the literature as a B-acute lymphoblastic leukemia case. On the contrary, in our patient immunologic testing demonstrated a high activity of T lymphocytes, however, inflammation was excluded. To the best of our knowledge this is the first described case of systemic JXG with determined karyotype representing unusual chromosomal aberrations.

A high yielding three-step procedure was applied for the synthesis of N-(imidazolidin-2-ylidene)-1-arylmethanamine oxides 3 (α-aminonitrones) starting from the easily accessible imidazolidin-2-one O-benzyl oxime 1. The α-aminonitrone-α-iminohydroxyloamine tautomerism of these products was studied theoretically and the structures of the synthesised compounds were confirmed by single crystal X-ray crystallographic analysis. The compounds were evaluated in vitro for their binding affinities to α(1) and α(2) adrenoceptors as well as imidazoline I(1) and I(2) receptors. The highest potencies at the α(2) adrenergic receptors were observed for compounds bearing biphenyl (4h, K(i) = 9 nM) and naphthyl (4i, K(i) = 92 nM) moieties. Compounds 4h and 4i were further tested in vivo for their cardiovascular and sedative-hypnotic effects in rats.

The surface tensions of binary mixtures containing the ionic liquid 1-ethyl-3-methyl-imidazolium bis[(trifluoromethyl)sulfonyl]imide ([EMIM][NTf2]) and the aprotic solvents tetrahydrofuran (THF) or acetonitrile were measured at temperatures in the range from (293.15 to 313.15) K (or to 308.15 K for the system with THF) using the pendant drop method. On the basis of these experimental results and activity coefficients taken from vapor pressure measurements, the Gibbs excess surface concentrations for mixtures were calculated. The results and their relationship to electrolyte solutions are discussed.

This paper describes selected thermophysical properties of the newly obtained paramagnetic inky. opaque ionic liquid. 1-butyl-3-methylimidazolium tetraisothiocyanato-cobaltate(II) ((BMlm) 2 (Co(NCS) 4 ]). Some properties of the homologous ionic liquid (IL), 1-ethyl-3-methylimidazolium tetraisothiocyanato-cobaltate(II) ((EMIm) 2 [Co(NCS) 4 ]), have been presented earlier and are discussed here together with those for (BMIm) 2 [(Co(NCS) 4 ]. On the basis of experimental densities, kinematic viscosities, conductivities, and surface tensions, some additional parameters have been determined, i.e., expansivity coefficients and surface thermodynamic properties. The influence of structural variation in the 1-alkyl-3-methylimidazolium cation is also discussed.

Densities of six binary mixtures containing the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide or 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide mixed with tetrahydrofuran or acetonitrile or dimethyl sulfoxide were determined at atmospheric pressures in the temperature range between 293.15 K and 313.15 K. On the basis of the experimental densities, excess molar volumes were calculated. Comparison of excess molar volumes of six binary systems reveals the slight influence of the IL’s cation on these physical properties and the small temperature dependence of VE for systems containing dimethyl sulfoxide.

N-[(Imidazolin-2-yl)amino]indolines and N-[(imidazolin-2-yl)amino]-1,2,3,4-tetrahydroquinolines, previously described in patent literature as hypertensive agents, were synthesized and tested in viny for their affinities to α1- and α2-adrenoceptors as well as imidazoline I, and I2 receptors. The compounds most potent at either α1- or α2-adrenoceptors were administered intravenously to normotensive Wistar rats to determine their effects on mean arterial blood pressure and heart rate. Upon intravenous administration at dose of 0.1 mg/kg to normotensive male Wistar rats, the initial transient pressor effect was followed by long-lasting hypotension and bradycardia. In view of the above results the 1-[(imidazolin-2-yl)amino]indolines and [(imidazolin-2-yl)amino]-1,2,3,4-tetrahydroquinolines are now found to possess circulatory profile characteristic of the centrally acting clonidine-like hypotensive imidazolines.

Evaluation of detection and drug resistance of Mycobacterium tuberculosis in patients from the Łódzkie Voivodship in the period 2009 - 2013.The data presented in the study include information obtained while diagnosing patients from the Łódzkie Voivodship in order to detect infections with Mycobacterium tuberculosis in the period 2009-2013.In 2009-2013 we analyzed clinical specimens for the purpose of detection of Mycobacterium tuberculosis. Tubercle bacilli were confirmed in 5621 specimens in 2196 patients; positive bacterioscopy results were observed in 1724 clinical specimens. In the study period 18 clinical specimens obtained from children contained tubercle bacilli. In the period 2009-2013 we noted multi-drug resistant (MDR) strain in 41 clinical specimens, which made up 1.8% of strains with known results of drug-sensitivity. In 5 clinical specimens we observed extensively-drug resistant (XDR) strain, which made up 0.2% of strains with known results of drug-sensitiveness. 12 clinical specimens appeared to contain pre-XDR strain, which constituted 0.6% of strains with known results of drug-sensitivity.Despite advances in the diagnostics and treatment of tuberculosis (TB) this diseases still poses a serious medical problem. The detection level in the period 2009-2013 is relatively unchanged, with regards to both bacterioscopy and culture methods. Thus, the laboratory detection of tuberculosis bacilli is similar. It directly results from the enforcement of strict procedures regarding the quality of specimens collected for microbiological purposes and the control of the performed tests, which contributes to a greater number of confirmed cases of TB. In the study period the number of new cases of the infectious diseases is variable. Only in children this number remains stable over the years. Researchers observe that tubercle bacilli are resistant to basic first-line treatment drugs. They also note the occurrence of MDR, pre-XDR and XDR strains. Hence, it is important to regularly and carefully monitor the sensitivity of Mycobacterium tuberculosis to antibiotics administered in a long-term anti-tuberculosis therapy.

Secretion of parathormone (PTH), the main parathyroid hormone, which is under the control of the calcium sensing receptor, might be inhibited by calcimimetics and stimulated by calcilytics. Parathyroid glands also secrete parathyroid hypertensive factor. Recently, it was shown that calcimimetic NPS R-568 induced decreased blood pressure in spontaneously hypertensive rats (SHR) in the presence of parathyroid glands. Therefore, the aim of this study was to determine whether administration of the calcilytic NPS 2143 provoked an increase of mean arterial blood pressure (MAP) in normotensive rats. We used male Wistar rats anaesthetized with thiopental. Clearance experiments were performed and the effect of bolus, 1 mg/kg body weight i.v. of NPS 2143 on MAP in the presence and absence of thyroparathyroidectomy (TPTX) was monitored continuously. Calcilytic properties of NPS 2143 were confirmed directly by a significant (P < 0.05) increase of plasma PTH concentration, and indirectly by a rise of plasma Ca2+ concentration and urinary fractional phosphate excretion (FE Pi). NPS 2143 administration markedly (P < 0.05) increased MAP, calculated as the difference ( Δ ) in MAP between sequential measurements and the time of bolus injection of calcilytic. The observed increase of blood pressure in the NPS 2143 group was also significant (P < 0.05) compared with the control group. Performance of TPTX prevented the hypertensive effect of NPS 2143. We conclude that NPS 2143 is responsible for increased blood pressure in rats in the presence of parathyroid glands.

The selected strains of microscopic fungi, Haematonectria haematococca (BwIII43, K37) and Trichoderma harzianum (BsIII33), decolorized the following monoathraquinone dyes with different efficiency: 0.03 % Alizarin Blue Black B, 0.01 % Carminic Acid, 0.01 % Poly R-478, and 0.2 % post-industrial lignin. The most effective was the removal of 0.03 % Alizarin Blue Black B (50–60 %) and 0.01 % Carminic Acid (55–85 %). The principal component analysis (PCA) method was applied to determine the main enzyme responsible for the biodecolorization process of the dye substrates and indicated that horseradish-type (HRP-like), lignin (LiP), and manganese-dependent (MnP) peroxidases were responsible for the decolorization of anthraquinone dyes by the strains tested. The participation of particular enzymes in the decolorization of monoanthraquinone dyes ranged from 44.48 to 51.70 % for 0.01 % Carminic Acid and from 38.46 to 61.12 % for Poly R-478. The highest precipitation in decolorization of these dyes showed HRP-like peroxidase, respectively, 54–74 and 70–95 %. The degree of decolorization of 0.2 % post-industrial lignin by the selected strains of H. haematococca and T. harzianum amounted to 58.20, 61.38, and 65.13 %, respectively. The rate of 0.2 % post-industrial lignin decolorization was conditioned by the activity of HRP-like (71–90 %) and LiP (87–94 %) peroxidases. Electronic supplementary material The online version of this article (doi:10.1007/s11270-015-2473-8) contains supplementary material, which is available to authorized users.

International audience; Hitherto, the field of nanomedicine has been overwhelmingly dominated by the use of mesoporous organosilicas compared to their metal oxide congeners. Despite their remarkable reactivity, titanium oxide-based materials have been seldom evaluated and little knowledge has been gained with respect to their "structure-biological activity" relationship. Herein, a fruitful association of phosphorus dendrimers (both "ammonium-terminated" and "phosphonate-terminated") and titanium dioxide has been performed by means of the sol-gel process, resulting in mesoporous dendrimer-coated nanosized crystalline titanium dioxide. A similar organo-coating has been reproduced using single branch-mimicking dendrimers that allow isolation of an amorphous titanium dioxide. The impact of these materials on red blood cells was evaluated by studying cell hemolysis. Next, their cytotoxicity toward B14 Chinese fibroblasts and their antimicrobial activity were also investigated. Based on their variants (cationic versus anionic terminal groups and amorphous versus crystalline titanium dioxide phase), better understanding of the role of the surface-interface composition and the nature of the framework has been gained. No noticeable discrimination was observed for amorphous and crystalline material. In contrast, hemolysis and cytotoxicity were found to be sensitive to the nature of the interface composition, with the ammonium-terminated dendrimer-coated titanium dioxide being the most hemolytic and cytotoxic material. This surface-functionalization opens the door for creating a new synergistic machineries mechanism at the cellular level and seems promising for tailoring the biological activity of nanosized organic-inorganic hybrid materials.