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In this study, a CIGS solar cell with a Mo/Cu(In0.7Ga0.3)Se2(CIGS)/CdS/ZnO/Al-doped ZnO (AZO) structure was simulated by Atlas silvaco-TCAD software. The photovoltaic characteristics of solar cells using CdS and ZnSe buffer layers were calculated and compared. Then, the photovoltaic characteristics were examined with different thicknesses of the ZnSe buffer layer. The 25 nm thickness was selected as the optimum thickness. After optimization of the ZnSe layer thickness, the photovoltaic characteristics of solar cells were evaluated by changing the conduction band offset (CBO). The highest CIGS solar cell conversion efficiency was obtained in the range from -0.5 eV to +0.5 eV for CBO. Finally, graphene was replaced with Al-doped ZnO (AZO) due to its high optical transparency, high carrier mobility, and proper mechanical properties. Graphene was used as a monolayer and multilayer as a transparent conductive oxide (TCO) layer. Simulations predicted the highest efficiency for solar cell structure based on Mo/CIGS/ZnSe/i-ZnO/monolayer graphene and the photovoltaic parameters were Jsc=38.64 mA/cm², Voc=0.67 V, FF=79.33% and η=20.71%. [ABSTRACT FROM AUTHOR]

Human epidermal growth factor receptor 2 (HER2)‐positive breast cancer (BC) comprises around 20–30% of all BC subtypes and is correlated with poor prognosis. For many years, trastuzumab, a monoclonal antibody, has been used to inhibit the HER2 activity. Though, the main resistance to trastuzumab has challenged the use of this drug in the management of HER2‐positive BC. Therefore, the determination of resistance mechanisms and the incorporation of new agents may lead to the development of a better blockade of the HER family receptor signaling. During the last few years, some therapeutic drugs have been developed for treating patients with trastuzumab‐resistant HER2‐positive BC that have more effective influences in the management of this condition. In this regard, the present study aimed at reviewing the mechanisms of trastuzumab resistance and the innovative therapies that have been investigated in trastuzumab‐resistant HER2‐positive BC subjects. [ABSTRACT FROM AUTHOR]

Purpose: The cytotoxic properties upon treatment with nicotine have been reported in several studies, but the underlying mechanisms remain not fully defined. The alpha7 nicotinic acetylcholine receptor (α7nAChR) is one of the important nicotinic receptors, which nicotine partly by binding to this receptor exerts its effects. The current study aimed to investigates the influences of nicotine on cellular proliferative and apoptotic activities and tried to determine the involvement of α7nAChR in these functions. Methods: Human hepatocellular carcinoma (HepG2) cell line was used to determine the individual or combined effects of treatments with nicotine (10 μM) and specific siRNA (100 nM) targeting α7nAChR expression. The MTT assay, DAPI staining assay, and flow cytometry assay were applied to measure the cell viability, apoptosis and cell cycle progression of the cells, respectively. In addition, the changes in the mRNA level of the genes were assessed by qRT-PCR. Results: Compared to control groups, the cells treated with nicotine exhibited significant dose-dependent decreases in cell viability (log IC50 = -5.12 ± 0.15). Furthermore, nicotine induced apoptosis and cell cycle arrest especially at G2/M Phase. The qRT-PCR revealed that nicotine increased the mRNA levels of α7nAChR as well as caspase-3 and suppressed the expression of cyclin B1. Treatment with α7-siRNA abolished these effects of nicotine. Conclusion: These experiments determined that upregulation of α7nAChR by nicotine inhibits HepG2 cells proliferation and induces their apoptosis. These effects blocked by treatment with α7-siRNA, which indicates the involvement of α7nAChR pathways in these processes. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) can control cancer and cancer stem cells (CSCs), and this topic has drawn immense attention recently. Stem cells are a tiny population of a bulk of tumor cells that have enormous potential in expansion and metastasis of the tumor. miRNA have a crucial role in the management of the function of stem cells. This role is to either promote or suppress the tumor. In this review, we investigated the function and different characteristics of CSCs and function of the miRNAs that are related to them. We also demonstrated the role and efficacy of these miRNAs in breast cancer and breast cancer stem cells (BCSC). Eventually, we revealed the metastasis, tumor formation, and their role in the apoptosis process. Also, the therapeutic potential of miRNA as an effective method for the treatment of BCSC was described. Extensive research is required to investigate the employment or suppression of these miRNAs for therapeutics approached in different cancers in the future. In the present review, we characterized the function and different characteristics of breast cancer stem cells and the function of microRNAs that are related to them. [ABSTRACT FROM AUTHOR]

Background: Aging is a universal phenomenon that will present itself as a dominant social and welfare challenge., Aim: This study was to examine life satisfaction among people residing in Gorgan and its correlation with certain demographic factors in 2013., Methods: A total of 250 elder people were selected for the study through the convenience sampling during 4 months. Data collected through life satisfaction index-A (LSIA). This instrument consists of 5 subscales, including, zest for life, resolution and fortitude, congruence between desired and achieved goals, positive self-concept and mood tone. The Multiple Linear Regression analysis was used in order to determine factors influencing the overall LSIA., Results: The overall LSIA score was 22.1 ± 7.5 with the maximum and minimum mean scores pertaining to the resolution and fortitude (6.1 ± 2.5) and the positive self-concept (3.1 ± 1.2) subscales, respectively. Level of education, type of living and gender were variables influencing the overall LSIA (P<0.05)., Conclusion: Given the overall LSIA, it appears that future plans for this age group should be seriously revised along with cultural plans for promoting reverence for old age in the general public., Competing Interests: The authors declare that there is no conflict of interests regarding the publication of this paper.