The investigation of YAlO3-NdAlO3 system, synthesis and characterization

The binary phase diagram of the YAlO3 (YAP) - NdAlO3 (NAP) system was determined by differential thermal analysis (DTA) and X-ray powder diffraction (XRD) measurements. High purity nanocrystalline powders and small single crystals of Y_{1-x}Nd_{x}AlO_3 (0 \leq x \leq 1) have been produced successfully by modified sol-gel (Pechini) and micro-pulling-down methods, respectively. Both end members show high mutual solubility >25% in the solid phase, with a miscibility gap for intermediate compositions. A solid solution with x \approx 0.2 melts azeotropic ca. 20 degrees below pure YAP. Such crystals can be grown from the melt without segregation. The narrow solid/liquid region near the azeotrope point could be measured with a "cycling" DTA measurement technique.Comment: 12 pages, 8 figures, submitted to J. Alloys. Comp

Identification of Extracellular Segments by Mass Spectrometry Improves Topology Prediction of Transmembrane Proteins

Transmembrane proteins play crucial role in signaling, ion transport, nutrient uptake, as well as in maintaining the dynamic equilibrium between the internal and external environment of cells. Despite their important biological functions and abundance, less than 2% of all determined structures are transmembrane proteins. Given the persisting technical difficulties associated with high resolution structure determination of transmembrane proteins, additional methods, including computational and experimental techniques remain vital in promoting our understanding of their topologies, 3D structures, functions and interactions. Here we report a method for the high-throughput determination of extracellular segments of transmembrane proteins based on the identification of surface labeled and biotin captured peptide fragments by LC/MS/MS. We show that reliable identification of extracellular protein segments increases the accuracy and reliability of existing topology prediction algorithms. Using the experimental topology data as constraints, our improved prediction tool provides accurate and reliable topology models for hundreds of human transmembrane proteins

The effect of anionic surfactant – polyvinylpyrrolidone complexes formed in aqueous solutions on physicochemical and functional properties of shampoos

Na podstawie analizy dostępnych wliteraturze wyników badań kompleksów polimerów z surfaktantami w roztworachwodnych opracowano receptury łagodnych dla skóry szamponów z udziałem dodecylosiarczanu sodu (SDS) oraz poliwinylopirolidonu (PVP). Oznaczono ich napięcie powierzchniowe, pianotwórczość i liczbę zeinową. Stwierdzono, że wodne roztwory PVP i SDS mogą być bazami szamponów o niskim potencjale drażniącym. Najkorzystniejszą ocenę (testy fizykochemiczne i sensoryczne) uzyskał szampon zawierający PVP90 (opracowany szampon oryginalny). Zestawiono wybrane właściwości użytkowe szamponu oryginalnego i produktu rynkowego. Jakość obu szamponów była porównywalna, natomiast wartość liczby zeinowej (LZ), będącej miarą potencjału drażniącego, była o ponad 30% mniejsza niż LZ szamponu rynkowego.Based on the analysis of published results of studies on the complexes of polymers with surfactants in aqueous solutions, shampoo formulations containing sodium dodecyl sulfate (SDS) and polyvinylpyrrolidone (PVP), which are mild to the skin, were developed. The measurements of surface tension, foamability and zein number confirmed that the aqueous solutions of PVP and SDS may be used as bases for shampoo with low irritation potential. The most favorable evaluation of physicochemical and sensory tests was obtained for a shampoo containing PVP90 (termed the original shampoo). A comparison of selected functional properties of the original product with the commercial product was performed. Both shampoos were of comparable quality, but the zein number (ZN), which is a measure of irritation potential, was reduced by more than 30 % compared to the commercial shampoo

The hematopoietic stem cell marker VNN2 is associated with chemoresistance in pediatric B-cell precursor ALL

Most relapses of acute lymphoblastic leukemia (ALL) occur in patients with a medium risk (MR) for relapse on the Associazione Italiana di Ematologia e Oncologia Pediatrica and Berlin-Frankfurt-M\ufcnster (AIEOP-BFM) ALL protocol, based on persistence of minimal residual disease (MRD). New insights into biological features that are associated with MRD are needed. Here, we identify the glycosylphosphatidylinositol-anchored cell surface protein vanin-2 (VNN2; GPI-80) by charting the cell surface proteome of MRD very high-risk (HR) B-cell precursor (BCP) ALL using a chemoproteomics strategy. The correlation between VNN2 transcript and surface protein expression enabled a retrospective analysis (ALL-BFM 2000; N 5 770 cases) using quantitative polymerase chain reaction to confirm the association of VNN2 with MRD and independent prediction of worse outcome. Using flow cytometry, we detected VNN2 expression in 2 waves, in human adult bone marrow stem and progenitor cells and in the mature myeloid compartment, in line with proposed roles for fetal hematopoietic stem cells and inflammation. Prospective validation by flow cytometry in the ongoing clinical trial (AIEOP-BFM 2009) identified 10% (103/1069) of VNN21 BCP ALL patients at first diagnosis, primarily in the MRD MR (48/103, 47%) and HR (37/103, 36%) groups, across various cytogenetic subtypes. We also detected frequent mutations in epigenetic regulators in VNN21 ALLs, including histone H3 methyltransferases MLL2, SETD2, and EZH2 and demethylase KDM6A. Inactivation of the VNN2 gene did not impair leukemia repopulation capacity in xenografts. Taken together, VNN2 marks a cellular state of increased resistance to chemotherapy that warrants further investigations. Therefore, this marker should be included in diagnostic flow cytometry panels