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MiRNAs derived from cancer-associated fibroblasts in colorectal cancer
No full textCurrently, the incidence of colorectal cancer (CRC) is increasing across the world. The cancer stroma exerts an impact on the spread, invasion and chemoresistance of CRC. The tumor microenvironment involves a complex interaction between cancer cells and stromal cells, for example, cancer-associated fibroblasts (CAFs). CAFs can promote neoplastic angiogenesis and tumor development in CRC. Mounting evidence suggests that many miRNAs are overexpressed (miR-21, miR-329, miR-181a, miR-199a, miR-382 and miR-215) in CRC CAFs, and these miRNAs can influence the spread, invasiveness and chemoresistance in neighboring tumor cells via paracrine signaling. Herein, we summarize the pathogenic roles of miRNAs and CAFs in CRC. Moreover, for first time, we highlight the miRNAs derived from CRC-associated CAFs and their roles in CRC pathogenesis. © 2019 Future Medicine Ltd
Electrochemical determination of the antipsychotic medication clozapine by a carbon paste electrode modified with a nanostructure prepared from titania nanoparticles and copper oxide
Get PDFA nanostructure was prepared from titania nanoparticles and copper oxide (TiO2NP@CuO) and used to modify a carbon paste electrode (CPE). The modified CPE is shown to enable sensitive voltammetric determination of the drug clozapine (CLZ). The sensor was characterized by various techniques and some key parameters were optimized. Under the optimum conditions and at a working potential of 0.6 V (vs. Ag/AgCl), the modified CPE has two linear response ranges, one from 30 pmol L�1 to 4 nmol L�1 of CLZ, the other from 4 nmol L�1 to 10 μmol L�1. The detection limit is as low as 9 pM. The transfer coefficient (α) and catalytic rate constant (kcat) were calculated and the reliability of the sensor was estimated for CLZ sensing in real samples where it gave satisfactory results. Figure not available: see fulltext.. © 2019, Springer-Verlag GmbH Austria, part of Springer Nature
Rapid and efficient ultrasonic assisted adsorption of diethyl phthalate onto FeIIFe2 IIIO4@GO: ANN-GA and RSM-DF modeling, isotherm, kinetic and mechanism study
Get PDFHerein, an ultrasonic assisted dispersive magnetic solid-phase adsorption method along with a high-performance liquid chromatography system for the diethyl phthalate (DEP) removal was developed. In this regard, magnetic iron oxide/graphene oxide (MGO) nanocomposites were prepared by a simple and effective chemical co-precipitation method, followed by nucleation and growth of nanoparticles. The structure and morphology of MGO was identified by Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX) spectroscopy X-ray diffraction (XRD), Vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and N2 adsorption-desorption techniques. The interactive and main effect of parameters such as pH, adsorbent dosage, sonication time and concentration of DEP involved in the adsorption process were set within the ranges 3.0�11.0, 0.10�0.50 g L�1, 1�5 min, 5�10 mg/L, respectively. Root means square error (RMSE), mean absolute error (MAE), absolute average deviation (AAD), and coefficient of determination (R2) was employed to examine the applicability of the response surface methodology (RSM) and artificial neural network (ANN) models for the description of experimental data. Compared to RSM, the ANN showed a more accurate performance for modeling the process of DEP adsorption. Using genetic algorithm-ANN, optimum conditions were set to 5.38, 334.7 mg/L, 3.723 min and 4.21 mg/L for pH, adsorbent dose, sonication time and concentration of DEP, respectively. Under the optimized conditions, the maximum adsorption capacity and adsorption factors were 116.933 mg/g and 100, respectively, while the relative standard deviations (RSDs) was <1.6 (N = 5). The isotherm models display that the Langmuir has the best fit with the equilibrium data, and adsorption kinetics followed the pseudo-second-order model. The thermodynamic results confirmed that the sorption was endothermic and occurred spontaneously. The results exhibited that MGO has excellent potential as an adsorbent for the removal of phthalates from the contaminated water. © 2019 Elsevier B.V
Improving and optimizing the structure of a cylindrical ionization chamber for radiation protection dosimetry: Guard electrode and chamber wall
No full textDue to relative ease, high accuracy, high sensitivity, appropriate response, and other properties of ionization chambers, they are usually employed as reference instruments in dosimetry and quality assurance programs. Therefore, any improvement and optimization in the structure of these dosimeters can lead to accurate measurements of the absorbed dose. In the present study, the structure of a specific cylindrical ionization chamber (PTW, model 23361, Freiburg, Germany) was improved and optimized. After the design and construction of the new cylindrical ionization chamber, the performance of this dosimeter was investigated by saturation, ion collection ef�ciency, polarization, leakage current, stability, and linearity of response tests. The findings of performance tests showed that the response of the introduced dosimeter agrees with the recommended standards. The new design and construction of the guard electrode, both in length and arrangement of the dosimeter structure, can improve the electric field and decrease the leakage current. Moreover, the use of pure graphite in the chamber's wall can result to improve in the electric field of the chamber's sensitive volume, thereby improving the performance of the dosimeter. © 2019 Elsevier Lt
Nurses' experiences of workplace violence in Kashan/Iran: A qualitative content analysis
Get PDFBackground: Nurses are at a high risk of workplace violence (WPV). This phenomenon is largely dependent on the sociocultural conditions. Objectives: This study explained the experiences of nurses about the WPV in medical, surgical, and emergency departments of a general hospital in Kashan, Iran, in 2017. Methods: In a qualitative content analysis, 13 nurses who had the experience of WPV were invited to participate in semi-structured interviews. The interviews were analyzed through conventional qualitative content analysis using the method suggested by Graneheim and Lundman. Results: Four themes were extracted from the interviews. The themes were: 'violent behaviors,' 'antecedents of violence,' 'violence management,' and 'violence outcomes'. Conclusion: WPV had many forms, antecedents, and consequences. Training the personnel and developing a committee for evaluating the incidents can prevent the occurrence of the violence. © 2019 Nursing and Midwifery Studies | Published by Wolters Kluwer - Medknow
Anti-cancer effects of cinnamon: Insights into its apoptosis effects
Get PDFCancer is known as a leading cause of death worldwide. In the last two decades, the incidence of cancer has been dramatically increased mostly due to lifestyle changes. The importance of this issue has attracted further attention to discover novel therapies to prevent and treat cancers. According to previous studies, drugs used to treat cancer have shown significant limitations. Therefore, the role of herbal medicines alone or in combination with chemotherapy drugs has been extensively studied in cancer treatment. Cinnamon is a natural component showing a wide range of pharmacological functions including anti-oxidant, anti-microbial and anti-cancer activities. Impaired apoptosis plays critical roles in the initiation and progression of cancer. Increasing evidence indicates that cinnamon, as a therapeutic agent, has anti-cancer effects via affecting numerous apoptosis-related pathways in cancer cells. Here, we highlighted anticancer properties of cinnamon, particularly through targeting apoptosis-related mechanisms. © 2019 Elsevier Masson SA
The effects of caffeine intake on weight loss: a systematic review and dos-response meta-analysis of randomized controlled trials
No full textThis systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effect of caffeine intake on weight loss. We searched the following databases until November 2017: MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials. The relevant data were extracted and assessed for quality of the studies according to the Cochrane risk of bias tool. We estimated an intake-status regression coefficient (Beta) for each primary study and estimated the overall pooled Beta and SE using random effects meta-analysis on a double-log scale. Heterogeneity between studies was assessed by the Cochran Q statistic and I-squared tests (I2). Thirteen RCTs with 606 participants were included in the meta-analyses. The overall pooled Beta for the effect of caffeine intake was 0.29 (95CI: 0.19, 0.40; Q = 124.5, I2 = 91.2) for weigh, 0.23 (95CI: 0.09, 0.36; Q = 71.0, I2 = 93.0) for BMI, and 0.36 (95 CI: 0.24, 0.48; Q = 167.36, I2 = 94.0) for fat mass. For every doubling in caffeine intake, the mean reduction in weight, BMI, and fat mass increased 2 Beta-fold (20.29 = 1.22, 20.23 = 1.17, and 20.36 = 1.28), which corresponding to 22, 17, and 28 percent, respectively. Overall, the current meta-analysis demonstrated that caffeine intake might promote weight, BMI and body fat reduction. © 2018, © 2018 Taylor & Francis Group, LLC
Preparation of Co2TiO4/CoTiO3/Polyaniline ternary nano-hybrids for enhanced destruction of agriculture poison and organic dyes under visible-light irradiation
No full textCo2TiO4/CoTiO3/Polyaniline ternary nano-hybrids were fabricated via sol�gel method and new gelling agent. The varied preparation factors like the type of calcination temperature, solvent and gelling agent were studied through the dimension and morphologies of final products. The photocatalytic activity of the Co2TiO4/CoTiO3/Polyaniline was verified via destruction of changing pollution like as diazinon, methylene blue, eosin Y, methyl orange, and phenol red. The maximum percentage of destruction of organic pollutions was found to be for diazinon (98.3). The BET analysis demonstrated that the preparation of nano-hybrids in both of presence valine and of phenylalanine can increase surface from 1.05 m2/g to 13.50 m2/g. The obtained ternary nano-hybrids were characterized through EDX, TEM, XRD, DRS, VSM, SEM, and FT-IR. © 2019, Springer Science+Business Media, LLC, part of Springer Nature
N-acetylcysteine in addiction management: Current knowledge and future perspectives
Get PDFDrug abuse disorders and addictive behaviors are serious public health problems and major contributors to the global burden of disease. Previous studies show that N-acetylcysteine (NAC) may be involved in neurodevelopment adult brain. The potential neuroprotective effect of NACis associated with modulate several neurological pathways, including prevention of oxidative stress or inflammation damage to nervous tissue and glutamate dysregulation, NAC is being explored as an adjunctive therapy for drug addiction and addiction management.We here review the role of NAC in the addiction, such as cannabis abuse, methamphetamine abuse, cocaine addiction, nicotine dependency, and gambling.Adequate administrate of NAC seems to be crucial in terms of addiction management. NAC is safe and well tolerated when administered orally but has documented risks with intravenous administration. An evidence study supports its use as an adjunctive therapy clinically for drug addiction, administered concomitantly with existing medications. The aim of this review is to assess the current knowledge related to the role of NAC administration on drug addiction and addiction management. © 2019, Advanced Scientific Research. All rights reserved
Comparing fracture resistance of endodontically treated teeth using different preparation-obturation combinations
Get PDFBackground: One of the main reasons for extraction of endodontically treated teeth is vertical root fracture (VRF). Some factors such as root canal treatment are involved in vertical root fracture because of their potential to weaken the tooth structure. Therefore, this study aimed to investigate the effect of combining different obturation materials and rotary systems on the fracture resistance of treated teeth. Methods: Eighty extracted maxillary central incisors were selected. The coronal portions of all teeth were removed at the cemento-enamel junction leaving the root segment of nearly 13 mm length. Roots were randomly divided into 2 groups according to the system used in root canal preparations, Group I: ProTaper, Group Π: Wave 1. Each main group was further subdivided into 2 equal subgroups according to the obturation system being used, Subgroup A: ProTaper, AH26 obturator, Subgroup B: ProTaper, Bioceramic, Subgroup C: Wave 1, AH26 obturator and Subgroup D: Wave 1, Bioceramic. Fracture resistance of each sample was measured by loading in universal testing machine. The results were analyzed with two- way ANOVA followed by multiple comparison Tukey HSD test. Results: The highest mean fracture resistance value (256.7N) was associated with Soft- Core/AH26 obturation and wave one (subgroup C), while the lowest value (239.8N) was for Bioceramic sealer and Wave 1 (subgroup D); however, there was no statistical significant difference (P>0.05) among all tested subgroups. Conclusion: All instrumentation techniques caused weakening of the root structure and made them susceptible to fiacture without any significant difference and therefore alternative strategies should be considered to reinforce endodontically treated roots. © 2019, Kerman University of Medical Sciences. All rights reserved