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Novel nanocomposites of polypyrrole (PPy) embedded in silica (SiO2) and iron phosphorus trisulphide (FePS3) nanoparticles have been fabricated. The nanocomposite's dielectric characteristics have been examined in relation to temperature ranges of 25-200°C and frequency ranges of 0.1-7 MHz. Fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM-EDX), transmission electron microscope (TEM), and dielectric measurements have all been used to evaluate the prepared nanocomposite. The monoclinic crystal structure of the prepared FePS3 and PPy/SiO2/FePS3 nanocomposite is confirmed by XRD, EDX, and TEM studies. The FePS3 is perfectly layered structure in the SEM image, and FePS3 and SiO2 particles are well intercalated, creating novel nanocomposites of two nanoparticle phases that served as a union network during the polymerization process. The IR spectrum shows that PPy is a dopant in the interlayer area of FePS3. The splitting major peak (570 cm-1) of FePS3 is visible at around 640 and 560 cm-1. The high AC conductivity values indicated that the combination of FePS3/SiO2 nano-matrix contains PPy at high packing densities and confirming the semiconducting properties of the nanocomposite to be used in several electronic applications. [ABSTRACT FROM AUTHOR]

The dielectric investigations of porous synthetic silica gel modified with polyaniline (PANI) and polyethylene glycol (PEG) polyblend at various concentrations are demonstrated in this paper. By using the chemical oxidative process to embed polyaniline (PANI) and polyethylene glycol (PEG) into a silica matrix, conducting gel nanocomposites were synthesized. For various dopant concentrations, the dielectric permittivity (ε′), D.C. conductivity (σdc), loss tangent (tanδ) and dielectric loss (ε″) were investigated. The samples were characterized using differential thermal analysis/thermogravimetric analysis, Fourier transform infrared spectroscopy and high‐resolution transmission electron microscopy. Depending on the co‐blend content, PANI‐PEG modified silica structures produce nanoparticles ranging in size from 9.9 to 48.1 nm. The variation of DC conductivity (σdc) with PANI/PEG content shows Maxwell‐Wagner Sillars (MWS) effect confirming the role of the conjugation and the structural order. [ABSTRACT FROM AUTHOR]

Background/Aims: Genetic alterations, including changes in the expression of spastic paraplegia 20 (SPG20) and serine/threonine protein kinase 31 (STK31), may play an important role in the carcinogenesis of colorectal cancer (CRC). Identification of such changes is suitable for the recognition of tumors at an early stage, which would significantly improve patient survival. While recent studies have identified that SPG20 and STK31 expression levels increase in CRC tissues, their use as a biomarker is yet to be investigated. Our aim was to determine whether circulating SPG20 and STK31 mRNAlevels could help distinguish between patients with CRC and healthy individuals. Additionally, we aimed to analyze the correlation between SPG20 and STK31 expression patterns and the tumor stage in patients with CRC. Methods: Venous blood samples from 50 patients with CRC and 50 healthy controls were used. RNA extraction was performed, and the mRNA expression of SPG20 and STK31 was determined using RT-qPCR. Results: STK31 and SPG20 mRNA levels were significantly upregulated in patients compared to those in controls. There was a strong positive correlation between the expression of the two potential tumor biomarkers, STK31 and SPG20 (R=0.636, p=0.000). However, there was no significant relationship between the expression of STK31 or SPG20 and patient data, including demographic, clinical, pathological, and laboratory data. Additionally, there was a significant correlation between the expression level of STK31, but not SPG20, and patient disease-free survival (DFS) and overall survival (OS). Conclusion: Circulating mRNA levels of SPG20 and STK31 could be used as ideal noninvasive biomarkers for early diagnosis of CRC. They could assist the oncologist in recommending appropriate management strategies for individual patients. [ABSTRACT FROM AUTHOR]

Background: Understanding the prognostic markers of multiple myeloma (MM) helps in optimizing therapeutic approaches. CD56 is frequently expressed by malignant plasma cells and its use as a prognostic marker in MM is promising. Aim: To evaluate prognostic value of CD56 expression in patients with MM. Methods: This study included 50 newly diagnosed patients with MM. Bone marrow samples were analyzed for CD56 expression by flow cytometry. All patients received bortezomib-based therapy for at least 3-4 months. Results: The median age of patients was 52 years (range 32-75) and 54% of them were males. The stage according to the International Staging System was I in 15 (30%) patients, II in 18 (36%) and III in 17 (34%). CD56 positivity was detected in 84% of enrolled patients. Multivariate analysis revealed that the lack of CD56 expression was an independent predictor of worse overall survival (HR = 4.31 [95% Confidence Interval: 1.23 - 15.13], p = 0.002). Conclusion: The present study suggests that CD56 negativity is associated with poor prognosis in patients with MM and that its incorporation in the risk panel of MM may be considered. Further studies with larger sample size to validate its prognostic value are needed. [ABSTRACT FROM AUTHOR]

Phosphosilicate (SiPh)/hyperbranched polyamidoamine (HYP)/Erbium (Er+3) hybrid nanocomposite (SiPh‐HYP‐Er+3) was prepared as novel optical planar waveguide material in two different forms, monolith and thin film. HYB was synthesized by one‐pot polymerization reaction via couple monomer methodology. Afterward, SiPh‐HYP‐Er+3 nanocomposite was prepared by doping the HYB and Er+3 nitrate into phosphosilicate matrix by using sol–gel technique. The prepared (SiPh‐HYP‐Er+3) nanocomposite was characterized by Fourier transform infrared (FTIR), X‐ray diffraction (XRD), the field emission scanning electron microscopy (FESEM), and high‐resolution transmission electron microscopy (HRTEM). Adjustable refractive indices (RIs) have been calculated for SiPh‐HYP‐Er+3 nanocomposites. The Vis–NIR photoluminescence emission spectra for monolith and thin film of SiPhEr+3 and SiPh‐HYP‐Er+3 nanocomposites under excitation of Ar‐Laser with 514 nm wavelength were dominated by an emission band centered at around 1.54 µm region. That band was assigned to 4I13/2 → 4I15/2 transition and the 4f‐transition state of Er+3 ions which was influenced by the presence of the hyperbranched polymeric material leading to coordination and Er+3 ions complex formation with the hyperbranched polymers. POLYM. COMPOS., 40:2029–2038, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A new series of pyrazole 4–7 and pyrazolo[1,5-a]pyrimidine 8–13 were synthesized by using a simple, efficient procedure, and screened for their in-vitro antimicrobial and antitumor activities. Symmetrical and asymmetrical 3,6-diarylazo-2,5,7-triaminopyrazolo[1,5-a]pyrimidine were synthesized by the conventional method and also subjected to microwave irradiation and under ultrasound conditions. The biological results revealed that most of the tested compounds proved to be active as antibacterial and antifungal agents. The antitumor activity of the synthesized compounds was evaluated against human cancer cell lines, MCF-7, HCT-116, and HepG-2, as compared with Doxorubicin as a control. [ABSTRACT FROM AUTHOR]

A new series of pyrazole 4 ⁻ 7 and pyrazolo[1,5- a ]pyrimidine 8 ⁻ 13 were synthesized by using a simple, efficient procedure, and screened for their in-vitro antimicrobial and antitumor activities. Symmetrical and asymmetrical 3,6-diarylazo-2,5,7-triaminopyrazolo[1,5- a ]pyrimidine were synthesized by the conventional method and also subjected to microwave irradiation and under ultrasound conditions. The biological results revealed that most of the tested compounds proved to be active as antibacterial and antifungal agents. The antitumor activity of the synthesized compounds was evaluated against human cancer cell lines, MCF-7, HCT-116, and HepG-2, as compared with Doxorubicin as a control.