Role of iron oxide core of polymeric nanoparticles in the thermosensitivity of colon cancer cell line HT-29

Purpose: In this study the effect of PLGA polymeric nanoparticles as a 5-fluorouracil (5-FU) carrier with and without iron oxide core and hyperthermia were investigated on the level of DNA damage in a spheroid culture model of HT-29 colon cancer cell lines by alkaline comet assay.Materials and methods: First, HT-29 colon cancer cells were cultured in vitro as spheroids with a mean diameter of 100 μm. The spheroids were then treated with different concentrations of 5-FU or nanoparticles as 5-FU carriers with and without an iron oxide core for one volume-doubling time of the spheroids (71 h) and hyperthermia at 43 °C for 1 h. Finally, the effect of treatment on viability and level of DNA damage was examined using trypan blue dye exclusion assay and alkaline comet assay, respectively.Results: Results showed that hyperthermia in combination with 5-FU or nanoparticles as 5-FU carriers significantly induced the most DNA damage as compared with the control group. The extent of DNA damage following treatment with 5-FU-loaded nanoparticles combined with hyperthermia was significantly more than for 5-FU combined with hyperthermia. In comparison to the effect of 5-FU-loaded nanoparticles with the iron oxide core and 5-FU-loaded nanoparticle without the iron oxide core, the nanoparticles with the iron oxide core combined with hyperthermia induced more DNA damage than the nanoparticles without the iron oxide core.Conclusions: According to this study, hyperthermia is a harmful agent and nanoparticles are effective delivery vehicles for drugs into colon cancer cells. The iron oxide filled nanoparticles increased the effect of the hyperthermia. All these factors have a significant role in the treatment of colorectal cancer cells. © 2015 Informa UK Ltd. All rights reserved

Role of resveratrol on the cytotoxic effects and DNA damages of iododeoxyuridine and megavoltage radiation in spheroid culture of U87MG glioblastoma cell line

The purpose of this study was to evaluate the effect of resveratrol on cytogenetic damages of iododeoxyuridine (IUdR) and x-ray megavoltage radiation (6 MV) in spheroid model of U87MG glioblastoma cancer cell line using clonogenic and alkaline comet assay. Cells were cultured as spheroids (350 μm) that were treated with 20 μM resveratrol, 1 μM IUdR and 2 Gy of 6 MV x-ray. After treatment, viability of the cells, colony forming ability and the induced DNA damages were examined using trypan blue dye exclusion, colonogenic and alkaline comet assay, respectively. Our results showed that resveratrol could significantly reduce the colony number and induce the DNA damages of the cells treated with IUdR in combination with 6 MV x-ray radiation. That results indicated that resveratrol as an inhibitor of hypoxia inducible factor 1 alpha (HIF-1α) protein in combination with IUdR as a radiosensitizer enhanced the radiosensitization of glioblastoma spheroid cells

Quantitative evaluation of polymer gel dosimeters by broadband ultrasound attenuation

Ultrasound has been examined previously as an alternative readout method for irradiated polymer gel dosimeters, with authors reporting varying dose response to ultrasound transmission measurements. In this current work we extend previous work to measure the broadband ultrasound attenuation (BUA) response of irradiated PAGAT gel dosimeters, using a novel ultrasound computed tomography system

A generalized finite element method for modeling arbitrary interfaces in large deformation problems

In this paper, a generalized–FEM technique is presented in modeling of arbitrary interfaces in large deformations. The method is used to model the internal interfaces and arbitrary geometries using a uniform non-conformal mesh. The technique is applied to capture independent deformations at both sides of separated element cut by the interface in a uniform regular mesh. In this approach, a uniform non-conformal mesh is decomposed into subelements that conform to the internal interfaces. The geometry of interface is used to produce various triangular, quadrilateral and pentagonal elements at the intersection of interface with regular FE mesh, in which the extra degrees-of-freedom are defined along the interface. The level set method is employed to describe the material geometry on the background mesh. The technique is used to extrude any arbitrary geometry from an initial background mesh and model under different external effects. The most feature of the technique is to introduce the conformal decomposition finite element method, in which the new conforming elements are produced in the uniform structured mesh by decomposing the uniform mesh into elements that is conformed to the material interfaces. Finally, several numerical examples are analyzed to demonstrate the efficiency of proposed technique in modeling arbitrary interfaces in large deformations

Magnetic resonance imaging of human-derived amniotic membrane stem cells using PEGylated superparamagnetic iron oxide nanoparticles

Objective: The label and detection of cells injected into target tissues is an area of focus for researchers. Iron oxide nanoparticles can be used to label cells as they have special characteristics. The purpose of this study is to examine the effects of iron oxide nanoparticles on human-derived amniotic membrane stem cell (hAMCs) survival and to investigate the magnetic properties of these nanoparticles with increased contrast in magnetic resonance imaging (MRI). Materials and Methods: In this experimental study, we initially isolated mesenchymal stem cells from amniotic membranes and analyzed them by?ow cytometry. In addition, we synthesized superparamagnetic iron oxide nanoparticles (SPIONs) and characterized them by various methods. The SPIONs were incubated with hAMCs at concentrations of 25-800 μg/mL. The cytotoxicity of nanoparticles on hAMCs was measured by the MTT assay. Next, we evaluated the effectiveness of the magnetic nanoparticles as MRI contrast agents. Solutions of SPION were prepared in water at different iron concentrations for relaxivity measurements by a 1.5 Tesla clinical MRI instrument. Results: The isolated cells showed an adherent spindle shaped morphology. Polyethylene glycol (PEG)-coated SPIONs exhibited a spherical morphology. The average particle size was 20 nm and magnetic saturation was 60 emu/g. Data analysis showed no signifcant reduction in the percentage of viable cells (97.86 ± 0.41) after 72 hours at the 125 μg/ml concentration compared with the control. The relaxometry results of this SPION showed a transverse relaxivity of 6.966 (μg/ml.s)-1 Conclusion: SPIONs coated with PEG used in this study at suitable concentrations had excellent labeling efficiency and biocompatibility for hAMCs

Mutagenic effects of nanosilverconsumer products: A new approach to physicochemical properties

Serious concerns have been expressed about potential health risks of Nano silver containing consumer products (AgNPs) therefore regulatory health risk assessment on such nanoparticles has become mandatory for the safe use of AgNPsinbiomedicalproducts with special concerns to the mutagenic potentials. In this study, we examined the inhibitory and mutagenicity effects of AgNPs in three different sizes of three colloidal AgNPs by Minimal Inhibitory concentration (MIC), Minimal Bactericidal Concentration (MBC) and Bacterial Reverse Mutation Assay (Ames test).All samples were characterized by transmission electron microscopy (TEM), X-Ray Diffraction (XRD) and Dynamic Light Scattering (DLS). DLS analysis showed lack of large agglomeration of the AgNPs and TEM results showed the spherical AgNPswith the average sizes of 15, 19.6, 21.8 nms. Furthermore the XRD analysis showed the crystalline samples with a face centered cubic structure of pure silver.AmestestresultsonColloidal silver nanoparticles showed lack of any mutation in TA100, TA98, YG1029S. typhymuriumstrains. In addition colloidal silver nanoparticles reduced the mutation ratesin all three strains in a concentration dependent manner.This finding creates a new issue in the possible antimutagenic effects of colloidal AgNPsas a new pharmaceutical productwhich should be consideredinfuture studiesby focusing onthephysicochemical properties of AgNPs. © 2015 by School of Pharmacy Shaheed Beheshti University of Medical Sciences and Health Services

Investigation of relationship between social capital and quality of life in female headed families

Background: Although most studies on female-headed families focus on women's access to social support, the associations between social capital and quality of life in these families are unclear in many societies (such as Iran). This study aimed to determine the associations between social capital and quality of life in Iranian female headed families. Methods: This cross-sectional study was performed on 152 female-headed households supported by Tehran Municipality, district 9 from April 2011 to July 2012. Convenience sampling was employed. Data were collected using demographic questionnaire, the Iranian version of World Health Organization Quality of Life, and the Word Bank Social Capital. Descriptive and multiple regression methods were used to analyze the data. Results: The mean±SD age of participants was 50.8±13.8 years. Findings revealed that in quality of life, the domains of environment health and social relation received the lowest (9.87 ± 2.41) and the highest (12.61 ±3.43) scores respectively; and with respect to social capital, membership in groups and social trust had the least (19.61 ± 17.11) and the most (51.04 ± 17.37) scores, respectively. The multiple regression model revealed a significant positive association between total score of the quality of life and the total score for the social capital (p < 0.001). Conclusion: Findings suggest that quality of life of female-headed families and social capital domains are strongly related. This means that by improving the social capital, women's life can also be improved

Gaining comprehensive data about sexual knowledge through surveys

Background: Delivery of sexual health services rely on rigorous facts extracted from surveys, but often those facts cannot be available due to the lack of culturally-sensitive questionnaires. Objective: our aim was to show the validity and reliability of the Persian version of the Acquisition of Sexual Information Test (ASIT), a measure selected due to its assemblages with Iranian culture. Materials and Methods: Forward-backward procedure was applied to translate the questionnaire. Cross-sectional study was carried out and psychometric properties of the Iranian version were tested in a thirty sample of reproductive-age women. Face validity was assessed by qualitative and quantitative methods. Content validity was also assessed by calculating two quantitative indicators as content validity index (CVI) and content validity ratio (CVR). Reliability was assessed by test-retest analyses. Results: Impact score was 1.5, the majority of participants (83.3%) stated that the overall level of questionnaire was high but some of the questions were irrelevant to sexual knowledge. Many questions (90%) gained a CVR less than 0.56, and all of them gained CVIs lower than 0.7. Correlation in test-retest reliability was 0.85

Evaluation of combination effects of 2-methoxyestradiol and methoxyamine on IUdR-induced radiosensitization in glioma spheroids

Background: Glioblastoma is the most common and most malignant cancer of central nervous system. Targeted radiotherapy is an effective method toward its treatment. Iododeoxyuridine (IUdR) is a halogenated thymidine analogue known to be effective as a radiosensitizer in human cancer therapy. In this study we have evaluated the combination effects of 2-Methoxyestradiol, an inhibitor of h y poxia inducible factor 1 α (HIF-1α) a n d Methoxyaminem, an inhibitor of base excision repair (BER) pathway on radiosensitization of IUdR in glioblastoma spheroid culture. Materials and Methods: The cytotoxic damages of DNA in U87MG cell line were compared using colony formation assay. Experiments were performed in large spheroids with a diameter of approximately 350 μm. Results: Evaluation of the effects of IUdR with 2ME2 and MX pretreatment on spheroid cultured cell followed by ionizing irradiation showed more enhancemented (p � 0.001) IUdR induced-radiosensitization. These results introduced a key role for 2ME2 in IUdR related studies. Conclusion: Pretreatment of tumor cells with IUdR, MX and 2ME2 before irradiation enhances tumor radiosensitization and may improve therapeu- tic index for IUdR and 2ME2. Iran. J. Radiat. Res., 2010; 7 (4): 211-216