O46. X-ray, γ and neutron irradiated spherical gold nanoparticles in human breast epithelium and human skin keratinocyte cells

2016 ◽  
Vol 32 ◽  
pp. 156
Author(s):  
M. de Kock ◽  
J. Nel ◽  
M. Engelbrecht ◽  
J.P. Slabbert
2016 ◽  
Vol 851 ◽  
pp. 26-30 ◽  
Author(s):  
Chang Shu Tsai ◽  
Jou Kang Hsiao

Citrate-coated gold nanoparticles (AuNPs) were prepared by using redox method and its characterization was studied thoroughly. In the preparation process, the varieties of factors were examined by TEM morphology, DLS zetasizer, XPS analysis and UV-Vis spectroscopy for evaluating their qualities and stability. The experimental results obtained under optimal condition, which are 100±5°C of reaction temperature, 4.5-6.4 of the pH value, 2-10 of molar ratio between trisodium citrate and tetrachloroauric acid, respectively. The fluorescent intensities of DCFDA-stain indicate the amount of generated ROS (reactive oxygen species) by AuNPs. The cell cycle for MDA-MB-231 human breast cancer cells exhibits S-phase arrest which can prevent mitosis. The radiosensitizing effect of AuNPs with 20 nm diameter in MDA-MB-231 was investigated by RCGG values (ratio of cell numbers in the G2/M phase to the G0/G1 phase, RCGG) and its radiosensitizing efficiency was ca. 2.29 to 3.75 fold. In this study, it was found that the radiosensitizing efficiency is related to the cytotoxicity by AuNPs. After the irradiation by x-ray to cells, the enhancement value in the presence of 20 nm diameter AuNPs were 17.2% for 3 Gy and 18.9% for 7 Gy respectively. Compared to the irradiated group alone, the enhancements values were 21.8% and 19.7, respectively.


2020 ◽  
Vol 15 (3) ◽  
pp. 253-259
Author(s):  
Asmaa Amer ◽  
Ahmed Nagah ◽  
Tianhai Tian ◽  
Xinan Zhang

Background: Cancer is a genetic disease caused by the accumulation of gene mutations. It is important to derive the number of driver mutations that are needed for the development of human breast cancer, which may provide insights into the tumor diagnosis and therapy. Objective: This work is designed to investigate whether there is any difference for the mutation mechanism of breast cancer between the patients in the USA and those in China. We study the mechanisms of breast cancer development in China, and then compare these mechanisms with those in the USA. Methods: This work designed a multistage model including both gene mutation and clonal expansion of intermediate cells to fit the dataset of breast cancer in China from 2004 to 2009. Results: Our simulation results show that the maximum number of driver mutations for breast epithelium stem cells of females in China is 13 which is less than the 14 driver mutations of females in the USA. In addition, the two-hit model is the optimal one for the tumorigenesis of females in China, which is also different from the three-hit model that was predicted as the optimal model for the tumorigenesis of females in the USA. Conclusion: The differences of the mutation mechanisms between China and the USA reflect a variety of lifestyle, genetic influences, environmental exposure, and the availability of mammography screening.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ewelina Piktel ◽  
Łukasz Suprewicz ◽  
Joanna Depciuch ◽  
Sylwia Chmielewska ◽  
Karol Skłodowski ◽  
...  

AbstractMedical device-associated infections are a serious medical threat, particularly for patients with impaired mobility and/or advanced age. Despite a variety of antimicrobial coatings for medical devices being explored to date, only a limited number have been introduced for clinical use. Research into new bactericidal agents with the ability to eradicate pathogens, limit biofilm formation, and exhibit satisfactory biocompatibility, is therefore necessary and urgent. In this study, a series of varied-morphology gold nanoparticles in shapes of rods, peanuts, stars and spherical-like, porous ones with potent antibacterial activity were synthesized and thoroughly tested against spectrum of Candida albicans, Pseudomonas aeruginosa, Staphylococcus aureus clinical strains, as well as spectrum of uropathogenic Escherichia coli isolates. The optimization of gold nanoparticles synthesis allowed to develop nanomaterials, which are proved to be significantly more potent against tested microbes compared with the gold nanoformulations reported to date. Notably, their antimicrobial spectrum includes strains with different drug resistance mechanisms. Facile and cost-efficient synthesis of gold nanoparticles, remarkable bactericidal efficiency at nanogram doses, and low toxicity, underline their potential for development as a new coatings, as indicated by the example of urological catheters. The presented research fills a gap in microbial studies of non-spherical gold nanoparticles for the development of antimicrobial coatings targeting multidrug-resistant pathogens responsible for device-associated nosocomial infections.


2021 ◽  
Vol 22 (7) ◽  
pp. 3691
Author(s):  
Oliver Schmutzler ◽  
Sebastian Graf ◽  
Nils Behm ◽  
Wael Y. Mansour ◽  
Florian Blumendorf ◽  
...  

Quantitative cellular in vitro nanoparticle uptake measurements are possible with a large number of different techniques, however, all have their respective restrictions. Here, we demonstrate the application of synchrotron-based X-ray fluorescence imaging (XFI) on prostate tumor cells, which have internalized differently functionalized gold nanoparticles. Total nanoparticle uptake on the order of a few hundred picograms could be conveniently observed with microsamples consisting of only a few hundreds of cells. A comparison with mass spectroscopy quantification is provided, experimental results are both supported and sensitivity limits of this XFI approach extrapolated by Monte-Carlo simulations, yielding a minimum detectable nanoparticle mass of just 5 pg. This study demonstrates the high sensitivity level of XFI, allowing non-destructive uptake measurements with very small microsamples within just seconds of irradiation time.


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