Toxicity Effect of Cancer Cell Labeled with Visible Luminescent Nanocrystalline Silicon Particles and Visualization Observationin Vivo

2008 ◽  
Vol 1145 ◽  
Author(s):  
Keisuke Sato ◽  
Masaki Hiruoka ◽  
Kohki Fujioka ◽  
Naoki Fukata ◽  
Kenji Hirakuri ◽  
...  
Keyword(s):  
Hela Cells ◽  
Uv Light ◽  
Light Exposure ◽  
Red Light ◽  
Nanocrystalline Silicon ◽  
Cellular Membrane ◽  
Cervical Carcinoma Cell Line ◽  
Cell Line Hela ◽  
Before And After

AbstractCytotoxicity of human cervical carcinoma cell line (HeLa cells) labeled with the nanocrystalline silicon (nc-Si) particles before and after ultraviolet (UV) light exposure has studied on the viability and cellular membrane damages. The viability and cellular membrane damages of HeLa cells changed at high particle concentration of 1.12 mg/ml. The viability of HeLa cells labeled with the UV-exposed nc-Si particles was higher than that of unexposed nc-Si particles. However, the variation of cellular membrane damages was almost same for the nc-Si particles before and after UV exposure. These results substantiated the low toxicity of nc-Si particles. Moreover, the HeLa cells labeled with the nc-Si particles exhibited green fluorescence. On the other hand,in vivotest of nc-Si particles estimated by the visualization observation of the circulation from the lymphatic vessel to the lymph node of a mouse. The transfer pathway of nc-Si particles could be clearly monitored by the strong emission of red light.

scholarly journals MODIFICATION OF NANOCRYSTALLINE SILICON BY POLYMERS FOR BIOMEDICAL APPLICATIONS

2019 ◽  
Vol 62 (9) ◽  
pp. 86-96
Author(s):  
Nina V. Sharonova ◽  
Anatoly A. Ischenko ◽  
Elena Yu. Yagudaeva ◽  
Svetlana V. Sizova ◽  
Evgeniya V. Smirnova ◽  
...  
Keyword(s):  
Silicon Nanoparticles ◽  
Visible Region ◽  
Average Diameter ◽  
Nanocrystalline Silicon ◽  
Aggregative Stability ◽  
Polymer Modification ◽  
Cervical Carcinoma Cell Line ◽  
Cell Line Hela

In this paper, it is proposed to use polymer-modified composite materials based on nanocrystalline silicon (nc-Si) as an alternative to organic fluorescent quantum dots traditionally used in medicine. A distinctive feature of nc-Si is a high absorption coefficient in the near UV and blue-violet range and the ability to transmit light in the visible region of the spectrum. The main advantage of silicon-based nanoparticles for in vivo use is their biodegradability and the absence of toxic properties. For hydrophilization of silicon nanoparticles, their surface was modified by amphiphilic biocompatible polymers: polyvinylpyrrolidone, a copolymer of maleic anhydride and 1-octadecene, cremophore, which is a polyoxyethylene derivative of hydrogenated castor oil. Silicon nanoparticles (nc-Si) with an average diameter of 4.5 nm, synthesized by annealing of SiO at 1150 °C, and functionalized with 1-octadecene photoluminescent in the red-infrared spectral region were used. The presence of the polymer shell on the surface of the nanoparticles was confirmed by FTIR spectroscopy. The sedimentation and aggregative stability of the particles in water were analyzed. It is shown that after the nc-Si polymer modification, the photoluminescent properties of nanoparticles are retained although the photoluminesce maxima were shifted to the blue region. Colorimetric MTT-assay of the cytotoxicity of the nanoparticles modified with polymers to monoclonal cells of human erythroleukemia K562 showed no toxicity for cells in culture at a particle concentration of up to 50 μg/ml. Subcellular localization of silicon nanoparticles into the human cervical carcinoma cell line HeLa was shown by means of fluorescence microscopy. The obtained polymer-modified nc-Si particles can be recommended for the purposes of bioimaging in in vitro and in vivo applications.

scholarly journals Stability and ocular biodistribution of topically administered PLGA nanoparticles

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sean Swetledge ◽  
Renee Carter ◽  
Rhett Stout ◽  
Carlos E. Astete ◽  
Jangwook P. Jung ◽  
...  
Keyword(s):  
Uv Light ◽  
Light Exposure ◽  
Polymeric Nanoparticles ◽  
Plga Nanoparticles ◽  
Eye Disease ◽  
Control Group ◽  
Eye Tissues ◽  
Nanoparticle Morphology ◽  
The Stability

AbstractPolymeric nanoparticles have been investigated as potential delivery systems for therapeutic compounds to address many ailments including eye disease. The stability and spatiotemporal distribution of polymeric nanoparticles in the eye are important regarding the practical applicability and efficacy of the delivery system in treating eye disease. We selected poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded with lutein, a carotenoid antioxidant associated with eye health, as our model ophthalmic nanodelivery system and evaluated its stability when suspended in various conditions involving temperature and light exposure. We also assessed the ocular biodistribution of the fluorescently labeled nanoparticle vehicle when administered topically. Lutein-loaded nanoparticles were stable in suspension when stored at 4 °C with only 26% lutein release and no significant lutein decay or changes in nanoparticle morphology. When stored at 25 °C and 37 °C, these NPs showed signs of bulk degradation, had significant lutein decay compared to 4 °C, and released over 40% lutein after 5 weeks in suspension. Lutein-loaded nanoparticles were also more resistant to photodegradation compared to free lutein when exposed to ultraviolet (UV) light, decaying approximately 5 times slower. When applied topically in vivo, Cy5-labled nanoparticles showed high uptake in exterior eye tissues including the cornea, episcleral tissue, and sclera. The choroid was the only inner eye tissue that was significantly higher than the control group. Decreased fluorescence in all exterior eye tissues and the choroid at 1 h compared to 30 min indicated rapid elimination of nanoparticles from the eye.

Persistent Luminescence Cr3+ Doped Spinels and Use as Biomarker for In Vivo Imaging

2014 ◽  
Vol 90 ◽  
pp. 157-165
Author(s):  
Suchinder K. Sharma ◽  
D. Gourier ◽  
B. Viana ◽  
T. Maldiney ◽  
E. Teston ◽  
...  
Keyword(s):  
Uv Light ◽  
Red Light ◽  
Band Gap Energy ◽  
Transparency Window ◽  
Persistent Luminescence ◽  
High Brightness ◽  
Mouse Imaging ◽  
Classical Quantum ◽  
Living Tissues

ZnGa2O4(ZGO) is a normal spinel. When doped with Cr3+ions, ZGO:Cr becomes a high brightness persistent luminescence material with an emission spectrum perfectly matching the transparency window of living tissues. It allowsin vivomouse imaging with a better signal to background ratio than classical quantum dots. The most interesting characteristic of ZGO:Cr lies in the fact that its LLP can be excited with red light, well below its band gap energy and in the transparency window of living tissues. A mechanism based on the trapping of carriers localized around a special type of Cr3+ions namely CrN2can explain this singularity. The antisite defects of the structure are the main responsible traps in the persistent luminescence mechanism. When located around Cr3+ions, they allow, via Cr3+absorption, the storage of not only UV light but also all visible light from the excitation source.

Biological Properties of Nanocrystalline Silicon Particles for Biomedical Applications

2006 ◽  
Vol 958 ◽  
Author(s):  
Keisuke Sato ◽  
Satoshi Yanagisawa ◽  
Akio Funakubo ◽  
Yasuhiro Fukui ◽  
Kenji Hirakuri ◽  
...  
Keyword(s):  
Small Intestine ◽  
Biomedical Applications ◽  
Uv Light ◽  
Red Light ◽  
Nanocrystalline Silicon ◽  
Biological Properties ◽  
Light Irradiation ◽  
Uv Light Irradiation ◽  
Luminescence Peak ◽  
Red Luminescence

ABSTRACTWe have studied the biological properties of nanocrystalline silicon (nc-Si) particles after injection at various places in a mouse. The nc-Si particles with a size of 2.5 nm and a concentration of 1.3 mg/ml were dispersed in a normal saline solution (NSS). The NSS dispersible nc-Si particles were safely injected into the mouse. When the nc-Si particles in the NSS were directly injected into the subcutaneous vein and the coronary artery of the heart by syringe, the condition of bloodstream at each place was confirmed by the red luminescence (peak wavelength at 720 nm) from the nc-Si particles under the ultraviolet (UV) light-irradiation. Moreover, the nc-Si particles in the NSS, which were injected into the vein in the sole, smoothly flowed to the small intestine, and the smooth fluidity of nc-Si particles was also observed for the condition of the peristalsis of the small intestine. The nc-Si particles in the small intestine emitted red light during peristalsis under the UV light-irradiation. The red luminescence at each place was very bright and could be clearly seen with the naked eye. These phenomenons were achieved by the utilization of the harmless material, the formation of nc-Si particles with the single-order-size and the realization of the stable surface modification to the nc-Si particles.

scholarly journals Eggshell microbiology and quality of hatching eggs subjected to different sanitizing procedures

2018 ◽  
Vol 53 (10) ◽  
pp. 1177-1183 ◽  
Author(s):  
Winnie Luiza dos Santos Clímaco ◽  
Érica de Faria Melo ◽  
Diego Pereira Vaz ◽  
Mariana Masseo Saldanha ◽  
Maria Fernanda Vieira da Silva Pinto ◽  
...  
Keyword(s):  
Uv Light ◽  
Light Exposure ◽  
Block Design ◽  
Bacterial Count ◽  
Microbial Load ◽  
Control Group ◽  
Resistance Force ◽  
Before And After ◽  
Disinfection Procedure

Abstract: The objective of this work was to evaluate the effect of different disinfection procedures as alternatives to formaldehyde fumigation on eggshell microbial load and quality of eggs from a 42-week-old Cobb commercial breeder flock. A total of 10,080 clean eggs collected from the nests were randomly distributed in a randomized complete block design, among the following treatment groups: 13.33 g m-3 formaldehyde fumigation, 5-10 ppm ozone fumigation, 6.36 mW cm-2 UV-C light irradiation, spraying with 1.56% hydrogen peroxide, spraying with 0.13% peracetic acid, spraying with water (wet control), and no disinfection procedure (dry control). Per treatment, eight samples of four eggs each were collected before and after the disinfection procedure, in order to count the number of Enterobacteriaceae and total aerobic mesophilic bacteria on the eggshell. Only eggs subjected to the formaldehyde and UV treatments showed a significant reduction in total aerobic mesophilic bacterial count on the eggshell, when compared with those of the dry control group. Treatments did not affect eggshell thickness and resistance force. UV light exposure is effective in reducing microbial load on 42-week-old breeder flock eggshells, without affecting their quality, and can be considered an alternative to formaldehyde disinfection.

Photo-Aging of Coating Based on Mixture of TDI and N75

2014 ◽  
Vol 1035 ◽  
pp. 453-457
Author(s):  
Jian Hong Tan ◽  
Sheng Tao Zhang ◽  
Bin Xiang ◽  
Shi Qin Wang ◽  
Guo Qing Zhang
Keyword(s):  
Uv Light ◽  
Light Exposure ◽  
Chemical Change ◽  
Toluene Diisocyanate ◽  
Mass Ratio ◽  
Scanning Electronic Microscopy ◽  
Sem Images ◽  
Infra Red ◽  
Before And After ◽  
Weather Resistance

The photoaging of coating based on toluene diisocyanate (TDI) and N75 was investigated though artificial light exposure. The properties of studied polyurethane coatings, such as film gloss loss and discoloration were examined at some aging interval. In addition, scanning electronic microscopy (SEM) and Fourier transform infra-red spectroscopy (FTIR) were used to measure the morphology and chemical change of coatings before and after exposed under UV light. It was found that the addition of N75 had a significant effect on the discoloration of polyurethane coating. Furthermore, SEM images showed that greater degradation occurred in the coating without N75. These findings were also supported by the results obtained from FTIR analysis and gloss loss. The above results suggested that a mixed curing agent system with a mass ratio of TDI to N75 between 5:5 and 3:7 be a possible substitute of pure N75 for weather resistance PU coatings.

scholarly journals 25-Hydroxycholecalciferol status in plasma is linearly correlated to daily summer pasture time in cattle at 56°N

2012 ◽  
Vol 108 (4) ◽  
pp. 666-671 ◽  
Author(s):  
Lone Hymøller ◽  
Søren K. Jensen
Keyword(s):  
Uv Light ◽  
Light Exposure ◽  
Linear Process ◽  
Organic Production ◽  
Sunlight Exposure ◽  
Large Herbivores ◽  
The Relationship ◽  
25 Hydroxycholecalciferol

In vitro studies with skin samples or pure precursors of cholecalciferol indicated that cholecalciferol synthesis during UV light exposure is a non-linear process. However, in vitro studies indicate nothing about the relationship between sunlight exposure and physiological cholecalciferol status of living organisms. Due to the lack of cholecalciferol in plant material, this relationship is important for herbivores including domestic cattle, particularly in organic agriculture, because the use of synthetic additives, like cholecalciferol, is restricted in order to fulfil the principles of sustainable organic production. The major physiological metabolite of cholecalciferol is the liver-derived 25-hydroxycholecalciferol (25(OH)D3). The purpose of the present study was to determine the relationship between sunlight exposure and 25(OH)D3 status in vivo in large herbivores during mid-summer at 56°N. Five groups of cows were given access to pasture during 15, 30, 75, 150 or 300 min daily for 28 d in June and plasma analysed for 25(OH)D3. Animals allowed 15, 30 or 75 min of daily access to pasture showed a declining linear relationship between plasma 25(OH)D3 and sampling day in contrast to animals allowed 150 or 300 min of pasture access which showed linear increasing plasma 25(OH)D3 status. Determined from the slopes of 25(OH)D3 concentration curves within treatments, breakeven for maintaining the initial 25(OH)D3 status of 45 nmol/l was 90 min pasture access per d during summer at 56°N.

scholarly journals Hinge region of Arabidopsis phyA plays an important role in regulating phyA function

2018 ◽  
Vol 115 (50) ◽  
pp. E11864-E11873 ◽  
Author(s):  
Yangyang Zhou ◽  
Li Yang ◽  
Jie Duan ◽  
Jinkui Cheng ◽  
Yunping Shen ◽  
...  
Keyword(s):  
Light Exposure ◽  
Red Light ◽  
Light Response ◽  
Hinge Region ◽  
Phytochrome A ◽  
Serine Residue ◽  
Signal Transducers ◽  
And Function

Phytochrome A (phyA) is the only plant photoreceptor that perceives far-red light and then mediates various responses to this signal. Phosphorylation and dephosphorylation of oat phyA have been extensively studied, and it was shown that phosphorylation of a serine residue in the hinge region of oat phyA could regulate the interaction of phyA with its signal transducers. However, little is known about the role of the hinge region of Arabidopsis phyA. Here, we report that three sites in the hinge region of Arabidopsis phyA (i.e., S590, T593, and S602) are essential in regulating phyA function. Mutating all three of these sites to either alanines or aspartic acids impaired phyA function, changed the interactions of mutant phyA with FHY1 and FHL, and delayed the degradation of mutant phyA upon light exposure. Moreover, the in vivo formation of a phosphorylated phyA form was greatly affected by these mutations, while our data indicated that the abundance of this phosphorylated phyA form correlated well with the extent of phyA function, thus suggesting a pivotal role of the phosphorylated phyA in inducing the far-red light response. Taking these data together, our study reveals the important role of the hinge region of Arabidopsis phyA in regulating phyA phosphorylation and function, thus linking specific residues in the hinge region to the regulatory mechanisms of phyA phosphorylation.

Characterization of Pseudomonas aeruginosa Films on Different Inorganic Surfaces before and after UV Light Exposure

Langmuir ◽  
2018 ◽  
Vol 34 (36) ◽  
pp. 10806-10815 ◽  
Author(s):  
Alexey V. Gulyuk ◽  
Dennis R. LaJeunesse ◽  
Ramon Collazo ◽  
Albena Ivanisevic
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Uv Light ◽  
Light Exposure ◽  
Before And After

Abstract P106: Development Of An Oral Drug Delivery System For The Cardio-protective Neuropeptide Alpha-calcitonin Gene Related Peptide

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Ambrish Kumar ◽  
Maelee G Williamson ◽  
Andrew Hess ◽  
Donald J DiPette ◽  
Jay D Potts
Keyword(s):  
Delivery System ◽  
Uv Light ◽  
Light Exposure ◽  
Calcitonin Gene Related Peptide ◽  
Deionized Water ◽  
Simulated Gastric Fluid ◽  
Oral Drug ◽  
Related Peptide ◽  
Calcitonin Gene

Alpha-calcitonin gene related peptide (α-CGRP) is a promising neuropeptide for the treatment of cardiovascular disease. We have developed an alginate biomaterial-based delivery system which increases the peptide’s bioavailability and have shown that subcutaneous delivery of alginate-CGRP microcapsules significantly improved cardiac function in pressure overload-induced heart failure in mice. The goal of this study is to develop efficient alginate microcapsule formulations for oral delivery of α-CGRP. An electrospray method was used to prepare four different formulations of alginate-CGRP microcapsules all of 200 μm diameter- i)- alginate-CGRP microcapsules, ii)- alginate-CGRP microcapsules with UV-light exposure, iii)- poly-L-ornithine (PLO) coated alginate-CGRP microcapsules, and iv)- PLO alginate-CGRP microcapsules with UV-light exposure. The stability of the microcapsules in the digestive tract was evaluated in deionized water, simulated gastric fluid (SGF; pH 1.2), and simulated intestinal fluid (SIF; pH 6.8). Over time, the size of all four microcapsule formulations remained almost unchanged in SGF, however all four of the microcapsule formulations swelled in presence of SIF. Compared to deionized water, the size of alginate-CGRP microcapsules after 6 h incubation in SIF increased by 1.7 fold. Since all four formulations yielded similar results, we chose to further study the alginate-CGRP microcapsules in vivo . To determine the bioactive nature of the released peptide, alginate microcapsules containing α-CGRP in doses of 1, 3, and 10 (mg/kg b.wt) were fed to male C57BL/6 mice via oral gavage. Systolic blood pressure (SBP) was subsequently measured by a tail-cuff method. α-CGRP microcapsules reduced SBP in a time-dependent manner. Alginate-CGRP at 1 and 3 mg/kg lowered the SBP by 25 mmHg for up to 4 h and 48 h, respectively. However, 10 mg/kg alginate-CGRP initially reduced SBP to undetectable levels which ultimately returned to baseline level by day 7. These studies indicate that alginate microcapsules can withstand the low pH of the stomach and the release of the peptide is bioactive in vivo . Thus, alginate microcapsules may provide an ideal formulation to deliver α-CGRP orally for the long-term treatment of cardiac diseases.

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