Directional migration of cancer cells induced by a blue light intensity gradient

Gold nanospheres (GNSs), biocompatible nanoparticles that can be designed to absorb visible and near-infrared light, have shown great potential in induced thermal treatment of cancer cells via Plasmonic Photothermal Therapy (PPTT) [3]. In this study, light induced heating of a water-based dispersion of 20 nm diameter GNSs was investigated at their plasmon resonance wavelength (λ = 520 nm). Temperature changes of the solution at the point of light irradiation were measured experimentally. A heat transfer model was used to verify the experimental data. The effect of two key parameters, light intensity and particle concentration, on the solution’s temperature was investigated. The experimental results showed a significant temperature rise of the GNS solution compared to de-ionized water. The temperature rise of GNS solution was linearly proportional to the concentration of GNS (from 0.25–1.0 C, C = 1×1013 particles per ml) and the light intensity (from 0.25 to 0.5 W cm−2). The experimental data matches the modeling results adequately. Overall, it can be concluded that the hyperthermic ablation of cancer cells via GNS can be achieved by controlled by the light intensity and GNS concentration. A novel component of this study is that a high power lamp source was used instead of a high power laser. This means that only low cost components were used in the current experimental set-up. Moreover, by using suitable filters and white light from the high power lamp source, it is possible to obtain light in many wavelength bands for the study of other nanoparticles with different plasmon wavelength ranges. The current results represtent just one example in this versatile experimental set-up developed. It should be noted, however, the plasmon resonance wavelength used in this study is not within the therapeutic window (750–1300 nm) [13]. Therefore, the GNSs used in this experiment are only applicable to the surface induced thermal treatment of cancer cells, for instance, in the skin.

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The Effects of Day Length and Light Intensity on Tile Growth of Barley

Australian Journal of Biological Sciences ◽

10.1071/bi9690053 ◽

1969 ◽

Vol 22 (1) ◽

pp. 53 ◽

Cited By ~ 2

Author(s):

D Aspinall

Keyword(s):

Light Intensity ◽

Linear Relationship ◽

Light Source ◽

Blue Light ◽

Floral Development ◽

Red Light ◽

Day Length

The acceleration of flowering in barley due to the inclusion of incandescent illumination in the light source has been shown to be due to the far�red content of the light. A linear relationship between floral development and intensity of far�red light in a 16�hr photoperiod has been established with the cultivar CI5611. Barley appears to be relatively unresponsive to blue light, however.

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Dual-Wavelength (UV and Blue) Controlled Photopolymerization Confinement for 3D-Printing: Modeling and Analysis of Measurements

Polymers ◽

10.3390/polym11111819 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1819 ◽

Cited By ~ 9

Author(s):

Jui-Teng Lin ◽

Da-Chuan Cheng ◽

Kuo-Ti Chen ◽

Hsia-Wei Liu

Keyword(s):

Light Intensity ◽

Blue Light ◽

Uv Light ◽

Numerical Data ◽

Coupling Factor ◽

Dual Wavelength ◽

Continuous Exposure ◽

Initiator Concentration ◽

Modeling And Analysis ◽

Inhibition Effect

The kinetics and modeling of dual-wavelength (UV and blue) controlled photopolymerization confinement (PC) are presented and measured data are analyzed by analytic formulas and numerical data. The UV-light initiated inhibition effect is strongly monomer-dependent due to different C=C bond rate constants and conversion efficacies. Without the UV-light, for a given blue-light intensity, higher initiator concentration (C10) and rate constant (k’) lead to higher conversion, as also predicted by analytic formulas, in which the total conversion rate (RT) is an increasing function of C1 and k’R, which is proportional to k’[gB1C1]0.5. However, the coupling factor B1 plays a different role that higher B1 leads to higher conversion only in the transient regime; whereas higher B1 leads to lower steady-state conversion. For a fixed initiator concentration C10, higher inhibitor concentration (C20) leads to lower conversion due to a stronger inhibition effect. However, same conversion reduction was found for the same H-factor defined by H0 = [b1C10 − b2C20]. Conversion of blue-only are much higher than that of UV-only and UV-blue combined, in which high C20 results a strong reduction of blue-only-conversion, such that the UV-light serves as the turn-off (trigger) mechanism for the purpose of spatial confirmation within the overlap area of UV and blue light. For example, UV-light controlled methacrylate conversion of a glycidyl dimethacrylate resin is formulated with a tertiary amine co-initiator, and butyl nitrite. The system is subject to a continuous exposure of a blue light, but an on-off exposure of a UV-light. Finally, we developed a theoretical new finding for the criterion of a good material/candidate governed by a double ratio of light-intensity and concentration, [I20C20]/[I10C10].

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SDF-1/CXCR4 axis promotes directional migration of colorectal cancer cells through upregulation of integrin αvβ6

Carcinogenesis ◽

10.1093/carcin/bgt331 ◽

2013 ◽

Vol 35 (2) ◽

pp. 282-291 ◽

Cited By ~ 39

Author(s):

Ben Wang ◽

Wenke Wang ◽

Weibo Niu ◽

Enyu Liu ◽

Xiangjuan Liu ◽

...

Keyword(s):

Colorectal Cancer ◽

Cancer Cells ◽

Directional Migration ◽

Integrin Αvβ6 ◽

Colorectal Cancer Cells ◽

Cxcr4 Axis

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Nocturnal hatching in the monogenean skin parasiteEntobdella hippoglossifrom the halibut,Hippoglossus hippoglossus

Parasitology ◽

10.1017/s0031182000045704 ◽

1974 ◽

Vol 68 (2) ◽

pp. 161-172 ◽

Cited By ~ 23

Author(s):

Graham C. Kearn

Keyword(s):

Light Intensity ◽

Blue Light ◽

Epidermal Cells ◽

Free Swimming ◽

Skin Mucus ◽

Hippoglossus Hippoglossus ◽

Monogenean Parasite ◽

The Relationship

When eggs of the monogenean parasiteEntobdella hippoglossi, from the skin of the halibut (Hippoglossus hippoglossus), are incubated at 7 °C in alternating 12 h periods of dim blue light (intensity about 3 nW/cm2) and darkness, free-swimming larvae are recovered mostly at the end of the first 2 h of the period of darkness. Larvae do not emerge in significant numbers when the eggs are mechanically disturbed during the light or dark periods, or when the eggs are placed in shadow for periods of 5–25 min during the illumination period. The treatment of fully developed eggs with washings from halibut or from sole or with halibut skin mucus failed to produce hatching.The free-swimming life of the larvae at 7 °C is in excess of 24 h and within 4 h of hatching at 4 °C some larvae are able to attach themselves to halibut skin and shed their ciliated epidermal cells.The relationship between the hatching pattern of the eggs of the parasite and the behaviour of the halibut is discussed.

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