Novel copolymers of styrene. 9. Fluoro ring-disubstituted butyl 2-cyano-3-phenyl-2-propenoates

Electrophilic trisubstituted ethylenes, ring-disubstituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH?C(CN)CO₂C₄H₉ (where R is 2-fluoro-5-methoxy, 2-fluoro-6-methoxy, 3-fluoro-4-methoxy, 4-fluoro-3-methoxy, 5-fluoro-2-methoxy, 3-fluoro-2-methyl, 3-fluoro-4-methyl, 4-fluoro-2-methyl, 4-fluoro-3-methyl, 5-fluoro-2-methyl were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and butyl cyanoacetate, and characterized by CHN analysis, IR, ¹H and ¹³C-NMR. All the ethylenes were copoly-merized with styrene (M₁) in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, ¹H and ¹³C-NMR. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (1.2–3.5% wt.), which then decomposed in the 500–800°C range.     

The direct effect of ultrasound on the extraction of date syrup and its micro-organisms

In the date syrup industry, date fruits are mixed with a suitable amount of water at a temperature greater than 50 °C for about 1 h. This condition is not sufficient for killing the micro-organisms present in the fruit. In addition, Overheating for a long time can damages nutritious materials and also changes the final product's color. Ultrasound was applied for improving the quantity and quality of the extraction, and also to overcome the health problem. In this research, the following variables were examined: date fruit/water ratio, ultrasonic intensity and temperature. The results showed that sonication under the proper conditions can lead to a higher extraction in a shorter time with a better physical quality of the product. Most importantly, the sonication significantly decreased the microbial count in comparison to the classical method. This study also confirmed the presence of anti-microbial substances in date fruit, and that ultrasonic waves can accelerate their effects.     

Use of ionic polymers as stationary and pseudo-stationary phases in the separation of ions by capillary electrophoresis and capillary electrochromatography

One of the problems with capillary electrophoresis is a lack of versatility regarding manipulation of the separation selectivity. A new and potentially universal concept is to introduce an ion-exchange component into a separation so that the migration of analyte ions is influenced by both their electrophoretic mobilities and their chromatographic properties. This may be accomplished by use of capillaries filled with or coated with solid ion-exchange polymers, or by addition of a soluble ionic polymer to the background electrolyte to create a pseudo-stationary phase. While each of these methods achieves the same result, they are not competitive, but rather complementary as the problems associated by one approach are overcome by the others. Recent highlights in the field are used to illustrate the flexibility that this approach provides to electrophoretic separation of ions.     

Proteomics of cypress pollen allergens using double and triple one-dimensional electrophoresis

Italian cypress (Cupressus sempervirens, Cups) pollen causes allergic diseases in inhabitants of many of the cities surrounding the Mediterranean basin. However, allergens of Cups pollen are still poorly known. We introduce here a novel proteomic approach based on double one‐dimensional gel electrophoresis (D1‐DE) as an alternative to the 2‐DE immunoblot, for the specific IgE screening of allergenic proteins from pollen extracts. The sequential one‐dimensional combination of IEF and SDS‐PAGE associated with IgE immunoblotting allows a versatile multiplexed immunochemical analysis of selected groups of allergens by converting a single protein spot into an extended protein band. Moreover, the method appears to be valuable for MS/MS identification, without protein purification, of a new Cups pollen allergen at 43 kDa. D1‐DE immunoblotting revealed that the prevalence of IgE sensitization to this allergen belonging to the polygalacturonase (PG) family was 70% in tested French allergic patients. In subsequent triple one‐dimensional gel electrophoresis, the Cups pollen PG was shown to promote lectin‐based protein‐protein interactions. Therefore, D1‐DE could be used in routine work as a convenient alternative to 2‐DE immunoblotting for the simultaneous screening of allergenic components under identical experimental conditions, thereby saving considerable amounts of sera and allergen extracts.     

Analysis of inorganic anions by electrostatic ion chromatography using zwitterionic/cationic mixed micelles as the stationary phase

The inability to separate fluoride, phosphate and sulfate by electrostatic ion chromatography (EIC) was overcome by using an ODS silica column coated with mixed zwitterionic-cationic surfactants as the stationary phase. The best results were obtained using the zwitterionic surfactant, 3-(N,N-dimethylmyristylammonium)-propanesulfonate (C₁₉H₄₁NO₃S), and the cationic surfactant, myristyltrimethylammonium, CH₃(CH₂)₁₃N⁺(CH₃)₃, in a 10:1 molar ratio in the column coating solution. With a dilute solution of sodium tetraborate as the eluent the model analyte anions were completely separated in the following elution order: F^–, HPO₄ ^2–, SO₄ ^2–, Cl^–, NO₂ ^–, Br^–, NO₃ ^–. The very early elution of phosphate and sulfate is most unusual and is unique to this system. Detection limits better than 1.1 × 10^–4 mM and linear calibration plots up to 7.0 mM were obtained with a suppressed conductivity system.     

A convenient synthesis of pyrazolo[3,4‐d]pyrimidine‐4,6‐dione and pyrazolo[4,3‐d]pyrimidine‐5,7‐dione derivatives

Pyrazolo‐[3,4‐d]pyrimidine‐4,6‐diones 5 and pyrazolo[4,3‐d]pyrimidine‐5,7‐diones 7 were synthesized by Curtius rearrangement of pyrazolic mono‐esters 2 and 3 followed by hetero‐cyclization via the ureas derivatives 4 and 6 under alkaline conditions.     

Protective role of estrogen against excessive erythrocytosis in Monge’s disease

Monge’s disease (chronic mountain sickness (CMS)) is a maladaptive condition caused by chronic (years) exposure to high-altitude hypoxia. One of the defining features of CMS is excessive erythrocytosis with extremely high hematocrit levels. In the Andean population, CMS prevalence is vastly different between males and females, being rare in females. Furthermore, there is a sharp increase in CMS incidence in females after menopause. In this study, we assessed the role of sex hormones (testosterone, progesterone, and estrogen) in CMS and non-CMS cells using a well-characterized in vitro erythroid platform. While we found that there was a mild (nonsignificant) increase in RBC production with testosterone, we observed that estrogen, in physiologic concentrations, reduced sharply CD235a⁺ cells (glycophorin A; a marker of RBC), from 56% in the untreated CMS cells to 10% in the treated CMS cells, in a stage-specific and dose-responsive manner. At the molecular level, we determined that estrogen has a direct effect on GATA1, remarkably decreasing the messenger RNA (mRNA) and protein levels of GATA1 (p < 0.01) and its target genes (Alas2, BclxL, and Epor, p < 0.001). These changes result in a significant increase in apoptosis of erythroid cells. We also demonstrate that estrogen regulates erythropoiesis in CMS patients through estrogen beta signaling and that its inhibition can diminish the effects of estrogen by significantly increasing HIF1, VEGF, and GATA1 mRNA levels. Taken altogether, our results indicate that estrogen has a major impact on the regulation of erythropoiesis, particularly under chronic hypoxic conditions, and has the potential to treat blood diseases, such as high altitude severe erythrocytosis.Subject terms: Haematopoietic stem cells, Myeloproliferative disease     

Fractal flux jumps in an organic superconducting crystal

Angle dependant torque magnetization measurements have been carried out on the organic superconductor, κ-(ET)₂Cu(NCS)₂ at extremely low temperatures (25-300 mK). Magneto-thermal instabilities are observed in the form of abrupt magnetization (flux) jumps for magnetic field sweeps of 0-20 T. A fractal analysis of the flux jumps indicate that the instabilities do show a self similar structure with a fractal dimension of varying between 1.15 and 1.6. The fractal structure of the flux jumps in our sample shows a striking similarity to that of MgB₂ thin film samples, in which magneto-optical experiments have recently shown that the small flux jumps are due to the formation of dendritic flux structures. These smaller instabilities act to suppress the critical current density of the thin films. The similarity of the flux jump structure of our samples suggests that we may also observing the dendritic instability, but in a bulk sample rather than a thin film. If true, this is the first observation of the dendritic instability in a bulk superconducting sample, and is likely due to the layered nature of κ-(ET)₂Cu(NCS)₂, which results in a quasi-two dimensional flux structure over the majority it's mixed state phase diagram.     

Size Distribution Evolution of NiO x H y and Au: NiO x H y Sols

The present work reports on the preparation of nickel oxi/hydroxide and gold composite nanoparticulate sols. The precursor was prepared as an alcoholic suspension of nickel oxi/hydroxide. Controlled amounts of 2,4-pentanedione (AcAc) were added to the nickel salt suspension and lead to the formation of a nickel complex. The dependence of the particle size with AcAc titration was followed by Small Angle X-Ray Scattering (SAXS). The results showed that the particle size distribution shifts towards low values with the increase in the AcAc concentration. The complex, obtained by adding an excess of the AcAc ligand, [Ni(AcAc)₂]·2H₂O, was identified by FTIR spectroscopy and X-ray diffraction. An AcAc specific volume was chosen in order to obtain a homogeneous sol of nickel oxi/hydroxide to which gold was added. The size distribution of the Au particles in this sol was followed by SAXS.