Evaluating the mechanism underlying antitumor effect of interleukin 27 on B cells of chronic lymphocytic leukemia patients

Chronic lymphocyte leukemia (CLL) is a B-cell malignancy resisted to apoptosis. Recently, some studies indicated that cytokines such as interleukin 27 (IL-27) can reduce B-cell proliferation. The aim of this study is to evaluate the mechanism underlying the proapoptotic effect of IL-27 on B cells of patients with CLL in comparison with B cells of normal subjects. The effect of IL-27 on the antitumor activity of natural killer (NK) and T cells was also evaluated. Peripheral blood mononuclear cells (PBMCs) were isolated from 35 patients with CLL and 15 normal subjects. B cells and PBMCs were cocultured with IL-27 and B cells apoptosis to evaluate proliferation. Both messenger RNA and protein expression of IL-27 and IL-27 receptor were determined using flow cytometry and real-time polymerase chain reaction analysis. To evaluate the apoptotic effect of IL-27 on B cells of patients with CLL, Annexin V-FITC and 7-AAD (BioLegend) fluorescent dyes were used. In addition, the IL-27 effect on activation of T cell and NK cell was determined by determining CD96 molecule expression. IL-27 and IL-27 receptor expression in patients with CLL was significantly lower than that of normal subjects (p < .05). IL-27 enhanced apoptosis of B cells in patients with CLL (p < .05) but this effect was not significantly observed in B cells of normal subjects (p > .05). Consequently, IL-27 reduced the proliferation of B cells and enhanced NK cell activity (p < .05). IL-27, through inducing apoptosis, can exert an inhibitory effect on cancer B cells of CLL patients with minimal effect on normal B cells.     

Assessment of genetic mutations in the XRCC2 coding region by high resolution melting curve analysis and the risk of differentiated thyroid carcinoma in Iran

Homologous recombination (HR) is the major pathway for repairing double strand breaks (DSBs) in eukaryotes and XRCC2 is an essential component of the HR repair machinery. To evaluate the potential role of mutations in gene repair by HR in individuals susceptible to differentiated thyroid carcinoma (DTC) we used high resolution melting (HRM) analysis, a recently introduced method for detecting mutations, to examine the entire XRCC2 coding region in an Iranian population. HRM analysis was used to screen for mutations in three XRCC2 coding regions in 50 patients and 50 controls. There was no variation in the HRM curves obtained from the analysis of exons 1 and 2 in the case and control groups. In exon 3, an Arg(188)His polymorphism (rs3218536) was detected as a new melting curve group (OR: 1.46; 95%CI: 0.432-4.969; p = 0.38) compared with the normal melting curve. We also found a new Ser(150)Arg polymorphism in exon 3 of the control group. These findings suggest that genetic variations in the XRCC2 coding region have no potential effects on susceptibility to DTC. However, further studies with larger populations are required to confirm this conclusion.     

Dosimetric effect of limited aperture multileaf collimator on VMAT plan quality: A study of prostate and head-and-neck cancers

Aim

The aim of study was to evaluate the dosimetric effect of collimator-rotation on VMAT plan quality, when using limited aperture multileaf collimator of Elekta Beam Modulator? providing a maximum aperture of 21 cm × 16 cm.

Thermo-mechanical properties of cubic titanium nitride

The equilibrium structure, elastic constants C_ij and thermodynamic functions of cubic titanium nitride (TiN) were calculated within the temperature range of 0–3100 K and under a pressure range 0–60 GPa. Properties were computed using the generalised gradient approximations (GGA) exchange-correlation functional. Calculated mechanical properties (Elastic constants, Young’s modulus and shear modulus) and phonon spectra of TiN obtained via robust DFT-QHA algorithm, were generally in a good agreement with available experimental and theoretical analogous values. In particular, a well-examined quasi-harmonic approximation method implemented in the Gibbs2 code is utilised herein to provide accurate estimation of thermal expansion coefficients, entropies, heat capacity values (at different combinations of temperature/volume/pressure) and Debye’s temperature. Parameters calculated herein shall be useful to elucidate the superior performance of TiN at harsh operational conditions encompassing elevated temperatures and pressures pertinent to cutting machineries and surface coatings.