Synthesis and Photo-Catalytic Activity of Nanoparticles with Structure "Core/Shell": Fe3O4@SiO2@TiO2

In this work, the nanosized magnetic Fe3O4@SiO2@TiO2 photocatalyst was prepared by sol-gel methods. First the nuclei of magnetite nanoparticles were prepared by co-precipitation of iron (II&III) salts solutions. Secondly, the magnetite nanoparticles were dispersed in ethanol using sonication, and solutions of both ammonia and tetraethoxysilane were added to the suspension under intense stirring, since it was suggested that the introduction of an intermediate passive SiO2 layer between the Fe3O4 and TiO2 phases inhibits the direct electrical contact and hence prevents the photodissolution of the magnetite phase and deterioration of the surface photocatalytic properties. Finally, solution of tetrabutoxytitanium was added dropwise to the mixture of Fe3O4@SiO2 nanoparticles under sonication & intense stirring. The resulting particles were separated using a magnet, washed and dried to constant weight, the yield was 70%. The photocatalytic activity of Fe3O4@ SiO2@TiO2 nanoparticles was investigated by photodegradation of methyl orange in aqueous solution under UV light irradiation. The photodegradation dynamics revealed that even though the oxidation rate decreases over time, about 90% of methyl orange is oxidized during the first 35 min

Combustion Characteristics of HAN-based Green Propellant Assisted with Nanoporous Active Carbons

Combustion of hydroxylammonium nitrate (95 wt.% HAN) ‒ water solution in presence of high specific surface area activated carbons is investigated in a constant-pressure bomb within the pressure range of 1‒6 MPa. The linear burning rate increased for the system of HAN admixed with activated carbons compared to those of the HAN alone. Moreover, the thermal decomposition of HAN (95 wt.%) ‒ water solution spiked with activated carbons was assessed by DTA – TG method. In the presence of activated carbons, the ability to trigger the decomposition at a lower temperature (86 °C vs 185 °C) was observed. The volatile products formed in the course of thermal decomposition of HAN, spiked with activated carbons were characterized by electron ionization mass spectrometry analysis. Primary products of HAN decomposition: m/z = 33 (NH2OH) and m/z = 63 (HNO3), which are further responsible for the formation of secondary products such as N2O, NO, HNO2, NO2, O2 etc. Significant reduction of NOx emissions during thermal decomposition of HAN (95 wt.%) ‒ water solution was observed (ca. 30%) in presence of activated carbons

Synthesis, Morphostructure, Surface Chemistry and Preclinical Studies of Nanoporous Rice Husk-Derived Biochars for Gastrointestinal Detoxification

This article summarizes the methodology of synthesis, surface functionalization and structural properties of rice husk-derived nanostructured carbon enterosorbents (biochars) in connection with the preliminary in vitro study results of uraemic toxin adsorption in model experiments, as well as preclinical trials in vivo. The obtained nanostructured carbon sorbents were studied using a number of modern physicochemical methods of investigation: low-temperature nitrogen adsorption, isotherms recording and calculation of the specific surface area, pore volumes were carried out using the Autosorb-1 "Quantachrome" device. Scanning electron microscopy and EDS-analysis. Mercury intrusion porosimetry analysis of the ACs were accomplished using "Quantachrome Poremaster" data analysis software. In vitro adsorption results assessed by use of HPLC and UV-spectroscopy for the nanostructured carbon sorbents with respect to the investigated low-molecule toxins suggest that the rice husks-derived carbon enterosorbents modified with the functional groups are able to reduce clinically significant levels of uraemic toxins and are comparable to the commercial enterosorbents. Based on the results of the comparative analysis for biocompatibility of canine kidney epithelial cells it was determined that the samples of the modified sorbents CRH P 450 and CRH 475 KOH 850 N do not exhibit cytotoxicity in comparison with the commercial carbon enterosorbent «Adsorbix Extra». According to the results of the in vivo studies, it was determined that there was a the positive effect of enterosorbent on uremia and intoxication

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Meiotic Spindle Pole Bodies Acquire the Ability to Assemble the Spore Plasma Membrane by Sequential Recruitment of Sporulation-specific Components in Fission Yeast

The spindle pole body (SPB) of Schizosaccharomyces pombe is required for assembly of the forespore membrane (FSM) during meiosis. Before de novo biogenesis of the FSM, the meiotic SPB forms outer plaques, an event referred to as SPB modification. A constitutive SPB component, Spo15, plays an indispensable role in SPB modification and sporulation. Here, we analyzed two sporulation-specific genes, spo13+ and spo2+, which are not required for progression of meiotic nuclear divisions, but are essential for sporulation. Spo13 is a 16-kDa coiled-coil protein, and Spo2 is a 15-kDa nonconserved protein. Both Spo13 and Spo2 specifically associated with the meiotic SPB. The respective deletion mutants are viable, but defective in SPB modification and in the onset of FSM formation. Spo13 and Spo2 localized on the cytoplasmic side of the SPB in close contact with the nascent FSM. Localization of Spo13 to the SPB was dependent on Spo15 and Spo2; that of Spo2 depended only on Spo15, suggesting that their recruitment to the SPB is strictly controlled. Spo2 physically associated with both Spo15 and Spo13, but Spo13 and Spo15 did not interact directly. Taken together, these observations indicate that Spo2 is recruited to the SPB during meiosis and then assists in the localization of Spo13 to the outer surface of the SPB