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Aims: Recent studies suggest that direct exposure of cells to fractionated radiotherapy might induce radioresistance. However, the effects of fractionated radiotherapy on the non-irradiated bystander cells remain unclear. We hypothesized that fractionated radiotherapy could enhance radioresistance and proliferation of bystander cells., Main Methods: Human tumor cell lines, including A549 and HT29 were irradiated (2 Gy per day). The irradiated cells (either A549 or HT29) were co-cultured with non-irradiated cells of the same line using transwell co-culture system. Tumor cell proliferation, radioresistance and apoptosis were measured using MTT assay, clonogenic survival assay and Annexin-V in bystander cells, respectively. In addition, activation of Chk1 (Ser 317), Chk2 (Thr 68) and Akt (Ser473) were measured via western blot., Key Findings: Irradiated HT29 cells induced conventional bystander effects detected as modulation of clonogenic survival parameters (decreased area under curve, D 10 and ED 50 and increased α) and proliferation in recipient neighbors. While, irradiated A549 cells significantly enhanced the radioresistance and proliferation of bystander cells. These changes were accompanied with enhanced activation of Chk1, Chk2 and Akt in non-irradiated bystander A549 cells. Moreover, both bystander effects (damaging and protective) were mediated through secreted factors., Significance: These findings suggest that fractionated radiotherapy could promote proliferation and radioresistance of bystander cells probably through survival and proliferation pathways., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Most dyes have aromatic rings in their structures, which make them highly toxic for human being and aquatic life. Heterogeneous photodegradation using TiO 2 nanoparticles is one of the most applied methods used for dye removal. The wide band gap of TiO 2 nanoparticles disables its use of the visible light and thus the vast potential of sunlight. To overcome this deficiency, Ag doped TiO 2 nanoparticles were loaded on Fe-ZSM-5., Methods: Fe-ZSM-5@TiO 2 -Ag photocatalyst was synthesized through sol-gel and hydrothermal methods to remove hazardous Reactive Red 195 (RR 195) from aqueous solution., Results: Pure phase of Fe-ZSM-5@TiO 2 -Ag with specific surface area of 332 m 2 /g was successfully synthesized. Formation of Ti-O-Ag functional group in the photocatalyst structure confirmed the nanocomposite form of the product. SEM and TEM images portrayed the synthesized zeolite and photocatalyst NPs in a size range of ≤100 nm with homogenous distribution of Ag doped TiO 2 on Fe-ZSM-5 surface. The band-gap energy of Fe-ZSM-5@TiO 2 -Ag was calculated 1.97 eV at λ = 630 nm. Photocatalytic activity of the photocatalyst under natural sunlight was investigated through photodecomposition of RR 195 in an aqueous solution. The dye photodecomposition of about 98% was achieved at photocatalyst concentration of 400 mg/L, pH of 3, and dye concentration of 50 mg/L at ambient temperature after 120 min under sunlight using 0.5 ml of TiO 2 and silver ammonium nitrate. The photocatalyst reusability was found significant after 5 frequent cycles., Conclusion: The novel Ag-doped TiO 2 -Fe-ZSM-5 nanocomposite with sunlight sensitivity can be a promising candidate to purify wastewater containing organic pollutants., Competing Interests: Conflict of interestThe authors declare that there is no conflict of interest.

Low frequency stimulation (LFS) has inhibitory effect on hyperexcitability during epileptic states. However, knowledge is lacking about LFS patterns that can exert an optimal antiepileptic effect. In this study, the effect of different numbers of pulses and current intensities of 1 Hz LFS applied at various time points of epileptiform activity was evaluated in high-K + model of epileptiform activity (EA). LFS was applied to the Schaffer collaterals, and changes in the excitability of CA1 pyramidal neurons were measured using whole-cell patch-clamp recording. Six hundred and 900 pulses of LFS at two current intensities (equal to and 1.5 times greater than the current intensity sufficient to elicit a 5 mV EPSP) administered at the beginning of EA revealed a stronger LFS inhibitory effect on EA-induced neuronal hyperexcitability when applied at higher pulse number and current intensity. LFS900 (high intensity) significantly hyperpolarized the membrane potential after a high-K + ACSF washout, reduced the frequency of spontaneous action potentials during EA, and attenuated neuronal firing frequency after high-K + ACSF washout. Moreover, applying LFS900 (high intensity) before EA induction and 8-10 min after EA initiation could not significantly affect neuronal hyperexcitability, compared to its application at the beginning of EA. This study's findings also offered long-term depression (LTD) as a probable mechanism for LFS' inhibitory role on EA-induced neuronal hyperexcitability. Therefore, the application of LFS (1 Hz) at 900 pulses and greater current intensity at the beginning of EA can exert a strong inhibitory effect on EA-induced neuronal hyperexcitability., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Introduction: It is a long time that natural toxin research is conducted to unlock the medical potential of toxins. Although venoms-toxins cause pathophysiological conditions, they may be effective to treat several diseases. Since toxins including scorpion toxins target voltage-gated ion channels, they may have profound effects on excitable cells. Therefore, elucidating the cellular and electrophysiological impacts of toxins, particularly scorpion toxins would be helpful in future drug development opportunities., Methods: Intracellular recording was made from F1 cells of Helix aspersa in the presence of calcium Ringer solution in which Na + and K + channels were blocked. Then, the modulation of channel function in the presence of extracellular application of F4 and F6 toxins and kaliotoxin (KTX; 50 nM and 1 μM) was examined by assessing the electrophysiological characteristics of calcium spikes., Results: The two active toxin fractions, similar to KTX, a known Ca 2+ -activated K + channel blocker, reduced the amplitude of AHP, enhanced the firing frequency of calcium spikes and broadened the duration of Ca 2+ spikes. Therefore, it might be inferred that these two new fractions induce neuronal hyperexcitability possibly, in part, by blocking calcium-activated potassium channel current. However, this supposition requires further investigation using voltage clamping technique., Conclusion: These toxin fractions may act as blocker of calcium-activated potassium channels., Competing Interests: Conflict of interest The authors declare no conflict of interest.

Background and Objectives: Anxiety affects various body systems, which leads to an increase in respiratory rate, heart rate, blood pressure, and myocardial oxygen demand. The aim of this study was to investigate the effect of hand and foot surface stroke massage on the level of anxiety and vital signs in patients with acute coronary syndrome (ACS)., Materials and Methods: The single-blind clinical trial was performed on 70 patients with ACS. The patients were randomly assigned to the case and control groups. Anxiety levels were controlled 30 min before and 15 min after the intervention. The vital signs were checked in the two groups before, immediately after, 60 min, and 90 min after the intervention. The data were analyzed using SPSS software, descriptive statistics (mean ± standard deviation), independent t-test, paired t-test, and chi-square test., Results: No significant difference was observed in the patients' levels of anxiety, systolic blood pressure, diastolic blood pressure, respiratory rate, and pulse rate before the intervention. However, after the intervention, the mean changes in the levels of anxiety, blood pressure, heart rate, and respiratory rate were significant., Conclusion: Hand and foot massage can be a useful nursing intervention in attenuating anxiety levels and improving the vital signs in patients., (Copyright © 2018. Published by Elsevier Ltd.)

Low-frequency electrical stimulation (LFS) is a potential therapeutic method for epilepsy treatment. However, the effect of different LFS characteristics including the number of pulses, intensity and the time of application on its antiepileptic action has not been completely determined. In the present study, epileptiform activity (EA) was induced in hippocampal slices by high-K + solution which was washed out after 20 min. The changes in the electrophysiological properties of CA1 pyramidal neurons were measured during and 30 min after EA using whole-cell patch-clamp recording. EA occurrence resulted in neuronal hyperexcitability. Application of 1-Hz LFS to the Schaffer collaterals at 600 and 900 pulses and two intensities (equal and 1.5 times more than an intensity sufficient to elicits a 5-mV EPSP) at the beginning of EA showed that 900-pulse LFS at high intensity had stronger preventing effect on high-K + -induced neuronal hyperexcitability by increasing the rheobase current, utilization time, first-spike latency, delay to first-rebound action potential and decreasing the number of rebound action potential. In addition, application of high-intensity 900-pulse LFS had better inhibitory effect on the neuronal hyperexcitability when applied at the beginning of EA compared to its administration before or at 8-10 min after EA. Therefore, it may suggest the inhibitory action of LFS on the neuronal hyperexcitability is augmented by increasing its number of pulses and intensity. In addition, there is a time window for LFS application so that its application at the beginning of EA has better inhibitory effect., (Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.)

Photocatalytic degradation of organic contaminants from petroleum refinery wastewater under UV and sunlight was investigated by immobilizing nanosized TiO2 photocatalyst into the structure of as-synthesized Fe-ZSM-5 zeolite via sol-gel method. Pure phase of TiO2/Fe-ZSM-5 photocatalyst with specific surface area of 304.6 m(2) g(-1) and loaded TiO2 of 29.28% was successfully synthesized. Effects of various operational parameters on treatment process were investigated by use of Response Surface Methodology (RSM). Maximum reduction of 80% COD was achieved at pH of 4, a photocatalyst concentration of 2.1 g l(-1), temperature of 45 °C and UV exposure time of 240 min. Gas chromatography-mass demonstrated an apparent shift in molecular weight from a higher fraction to a lower fraction even under sunlight. It is expected that the prepared photocatalyst is able to use ultraviolet and visible light energy. Results indicated that removal of COD degradation did not decrease as the reuse cycle of photocatalyst increased. Moreover, the potential to use sunlight energy and the simplicity of operation make photocatalysis an attractive prospect in terms of petroleum refinery wastewater treatment., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

There are very chemical reactions with very slow rates which can be catalyzed by enzymes. These biocatalysts need to moderate conditions for their catalytic activity and are stable in low temperature (between 15-50°C), average pH (5-10) and aqueous media. One of important things in enzymatic synthesis which has been recently noticed is the yield of reactions. Nowadays wide application of response surface methodology (RSM) was observed in organic chemistry. In one-variable-at-a-time technique only one parameter is changed and other parameters are kept at a constant level. It does not study the interactive effects among the variables, and does not illustrate the complete effects of the parameters on the process. Increasing the yield of product without increase in casts is carried out by modeling and optimization of reaction variables through statistical techniques such as RSM. In this paper, we reviewed some articles that used the RSM for optimization in the enzymatic synthesis.