scholarly journals NanoLuc Bioluminescence-Driven Photodynamic Activation of Cholecystokinin 1 Receptor with Genetically-Encoded Protein Photosensitizer MiniSOG

2020 ◽  
Vol 21 (11) ◽  
pp. 3763 ◽  
Author(s):  
Yuan Li ◽  
Zong Jie Cui
Keyword(s):  
Singlet Oxygen ◽  
Light Source ◽  
Light Emitting Diode ◽  
Calcium Oscillations ◽  
Entry Site ◽  
Photodynamic Action ◽  
Halogen Light ◽  
Halogen Light Source ◽  
External Light Source

In contrast to reversible activation by agonist, cholecystokinin 1 receptor (CCK1R) is permanently activated by singlet oxygen generated in photodynamic action, with sulphonated aluminium phthalocyanine or genetically encoded mini singlet oxygen generator (miniSOG) as photosensitizer. In these works, a halogen light source was used to power photodynamic action. For possible in vivo application of photodynamic CCK1R physiology, bearing a cumbersome light-delivery device connected to an external light source by experimental animals might interfere with their behavior. Therefore, in the present work, the possibility of bioluminescence-driven miniSOG photodynamic CCK1R activation was examined, as monitored by Fura-2 calcium imaging. In parallel experiments, it was found that, after plasma membrane (PM)-localized expression of miniSOGPM in AR4-2J cells, light irradiation with blue light-emitting diode (LED) (450 nm, 85 mW·cm−2, 1.5 min) induced persistent calcium oscillations that were blocked by CCK1R antagonist devazepide 2 nM. NanoLuc was expressed bicistronically with miniSOGPM via an internal ribosome entry site (IRES) sequence (pminiSOGPM-IRES-NanoLuc). The resultant miniSOGPM-IRES-NanoLuc-AR4-2J cells were found to generate strong bioluminescence upon addition of NanoLuc substrate coelenterazine. Strikingly, coelenterazine 5 microM was found to trigger long-lasting calcium oscillations (a hallmark for permanent CCK1R activation) in perifused miniSOGPM-IRES-NanoLuc-AR4-2J cells. These data indicate that NanoLuc bioluminescence can drive miniSOGPM photodynamic CCK1R activation, laying the foundation for its future in vivo applications.

Comparison of the effects of operating microscopes with light emitting diode and halogen light source on the eye: a rabbit study

2021 ◽  
pp. 1-7
Author(s):  
Bahri Aydın ◽  
Armagan Ozgur ◽  
Huseyin Baran Ozdemir ◽  
Pınar Uyar Gocun ◽  
Mehmet Arda Inan ◽  
...  
Keyword(s):  
Light Source ◽  
Light Emitting Diode ◽  
Light Emitting ◽  
Halogen Light ◽  
Halogen Light Source

scholarly journals Photodynamic Activation of Cholecystokinin 1 Receptor with Different Genetically Encoded Protein Photosensitizers and from Varied Subcellular Sites

Biomolecules ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1423
Author(s):  
Yuan Li ◽  
Zong Jie Cui
Keyword(s):  
Singlet Oxygen ◽  
Fluorescent Protein ◽  
Light Emitting Diode ◽  
Calcium Oscillations ◽  
Light Irradiation ◽  
Quantum Yields ◽  
Photodynamic Action ◽  
Led Light ◽  
Dinoroseobacter Shibae ◽  
Flavin Binding

Cholecystokinin 1 receptor (CCK1R) is activated by singlet oxygen (1O2) generated in photodynamic action with sulphonated aluminum phthalocyanine (SALPC) or genetically encoded protein photosensitizer (GEPP) KillerRed or mini singlet oxygen generator (miniSOG). A large number of GEPP with varied 1O2 quantum yields have appeared recently; therefore, in the present work, the efficacy of different GEPP to photodynamically activate CCK1R was examined, as monitored by Fura-2 calcium imaging. KillerRed, miniSOG, miniSOG2, singlet oxygen protein photosensitizer (SOPP), flavin-binding fluorescent protein from Methylobacterium radiotolerans with point mutation C71G (Mr4511C71G), and flavin-binding fluorescent protein from Dinoroseobacter shibae (DsFbFP) were expressed at the plasma membrane (PM) in AR4-2J cells, which express endogenous CCK1R. Light irradiation (KillerRed: white light 85.3 mW‧cm−2, 4’ and all others: LED 450 nm, 85 mW·cm−2, 1.5′) of GEPPPM-expressing AR4-2J was found to all trigger persistent calcium oscillations, a hallmark of permanent photodynamic CCK1R activation; DsFbFP was the least effective, due to poor expression. miniSOG was targeted to PM, mitochondria (MT) or lysosomes (LS) in AR4-2J in parallel experiments; LED light irradiation was found to all induce persistent calcium oscillations. In miniSOGPM-AR4-2J cells, light emitting diode (LED) light irradiation-induced calcium oscillations were readily inhibited by CCK1R antagonist devazepide 2 nM; miniSOGMT-AR4-2J cells were less susceptible, but miniSOGLS-AR4-2J cells were not inhibited. In conclusion, different GEPPPM could all photodynamically activate CCK1R. Intracellular GEPP photodynamic action may prove particularly suited to study intracellular GPCR.

scholarly journals Microleakage under Orthodontic Brackets Using High-Intensity Curing Lights

2009 ◽  
Vol 79 (1) ◽  
pp. 144-149 ◽  
Author(s):  
Mustafa Ulker ◽  
Tancan Uysal ◽  
Sabri Ilhan Ramoglu ◽  
Huseyin Ertas
Keyword(s):  
High Intensity ◽  
Light Emitting Diode ◽  
Bonferroni Correction ◽  
Light Emitting ◽  
Halogen Light ◽  
Halogen Light Source ◽  
Light Curing ◽  
Curing Light ◽  
High Intensity Light ◽  
Nail Varnish

Abstract Objective: To compare the microleakage of the enamel-adhesive-bracket complex at the occlusal and gingival margins of brackets bonded with high-intensity light curing lights and conventional halogen lights. Materials and Methods: Forty-five freshly extracted human maxillary premolar teeth were randomly separated into three groups of 15 teeth each. Stainless steel brackets were bonded in all groups according to the manufacturer's recommendations. Specimens (15 per group) were cured for 40 seconds with a conventional halogen light, 20 seconds with light-emitting diode (LED), and 6 seconds with plasma arc curing light (PAC). After curing, the specimens were further sealed with nail varnish, stained with 0.5% basic-fuchsine for 24 hours, sectioned and examined under a stereomicroscope, and scored for microleakage for the enamel-adhesive and bracket-adhesive interfaces from both the occlusal and gingival margins. Statistical analyses were performed using Kruskal-Wallis and Mann-Whitney U-tests with a Bonferroni correction. Results: The type of light curing unit did not significantly affect the amount of microleakage at the gingival or occlusal margins of investigated interfaces (P >.05). The gingival sides in the LED and PAC groups exhibited higher microleakage scores compared with those observed on occlusal sides for the enamel-adhesive and adhesive-bracket interfaces. The halogen light source showed similar microleakage at the gingival and occlusal sides between both adhesive interfaces. Conclusions: High-intensity curing units did not cause more microleakage than conventional halogen lights. This supports the use of all these curing units in routine orthodontic practice.

EVALUATION OF AN AUTOMATED COAGULATION ANALYZER

1987 ◽  
Author(s):  
M Johnston ◽  
M Andrew
Keyword(s):  
Thrombolytic Therapy ◽  
Light Source ◽  
Therapy Group ◽  
Screening Tests ◽  
Poor Correlation ◽  
Mean Values ◽  
Halogen Light ◽  
Halogen Light Source ◽  
Scientific Group ◽  
Time Required

The ACL (IL-Automated Coagulation Laboratory from the Fisher Scientific Group) is the first microcentrifugal analyzer incorporating 2 reading channels, a coagulometric channel consisting of a laser light source and a chromogenic channel consisting of a halogen light source. We have evaluated the instrument for precision and accuracy using different reagents for both clotting and the chromogenic assays. Replicate samples were run in both the PT and APTT modes using 4 different reagents. The reagent with the least particles had the greatest precision. The mean values for APTTs and PTs using a particle free reagent were 68.7 ± .83“ for the APTT (C.V. 1.2%), and 30.2 ± .33” (C.V. 1.1%) for the PT. A fibrinogen assay measured on the ACL (delta light scatter of the prothrombin time) was compared to the Clause fibrinogen assay in three population groups: the adult, the newborn and patients receiving thrombolytic therapy. The correlation for the adult and newborn was good with r values of .911 (n = 51) and .96 (n = 36) respectively. The thrombolytic therapy group had poor correlation r = .32. Antithrombin III (ATIII) and a2 antiplasmin (AP) assays were measured on the ACL using IIs chromogenic method. These were compared to an ATIII chromogenic method (Kahle) using a Gilford SBA 300 analyzer and α2 AP assay using a Protopath (Dade). The correlations were ATIII, r=.95 and α2 AP, r=.82. The plasminogen method of Friberger was adapted to the ACL giving us comparable results to those read off the Gilford SBA 300 (r=.93). With the introduction of the ACL we have been able to: 1) reduce the technical time required for assays by one half; 2) reduce reagent costs by one half to three-quarters; 3) reduce the amount of plasma required for screening tests by half the volume, which has greatly facilitated neonatal coagulation testing

scholarly journals Antimicrobial Photodynamic Action on Dentin Using a Light-Emitting Diode Light Source

2008 ◽  
Vol 26 (4) ◽  
pp. 281-287 ◽  
Author(s):  
Juçaíra S.M. Giusti ◽  
Lourdes Santos-Pinto ◽  
Antonio C. Pizzolito ◽  
Kristian Helmerson ◽  
Eurico Carvalho-Filho ◽  
...  
Keyword(s):  
Light Source ◽  
Light Emitting Diode ◽  
Light Emitting ◽  
Photodynamic Action

scholarly journals NPK DETECTION SPECTROSCOPY ON NON-AGRICULTURE SOIL

2016 ◽  
Vol 78 (11) ◽  
Author(s):  
Khairunnisa Mohd Yusof ◽  
Suhaila Isaak ◽  
Nurfatihah Che Abd Rashid ◽  
Nor Hafizah Ngajikin
Keyword(s):  
Near Infrared ◽  
Light Emitting Diode ◽  
Low Cost ◽  
Primary Objective ◽  
Optical Measurements ◽  
Light Emitting ◽  
Agriculture Soil ◽  
Agricultural Produce ◽  
Halogen Light ◽  
Halogen Light Source

Soil is a medium for plant roots to grow, absorb water and necessary solutes for growth. Soil macronutrient testing is helpful for determining the nutrients content in soil before applying fertilizer for quality and process controls of agricultural produce and soil fertility. Spectroscopy is an emerging technology which is rapid and simple has been widely used in agricultural and food analysis processes. The capability of spectroscopy to characterize material from the transmission or absorbance has been used in this paper to measure nitrogen (N), phosphorus (P) and potassium (K) content in non-agriculture soil. The paper details preliminary characterization of soil spectroscopy with a Deuterium-Halogen light source and Ocean Optic spectrometer to measure the absorbance level of the macronutrients. The extracted nutrients were mixed with the colour reagent and specific colored solution was developed. Two soil samples have been employed for the experimental characterization, which are mud flood and kaolin. The result shows that high absorbance level of N at 450 nm in wavelength, P at 750 nm for both samples.  The absorbance level of K was measured high at 500nm for mud flood and 450nm for kaolin. In addition, the tested macronutrients give similar wavelength of peak absorbance level at 970 nm for both samples. For future works, the optical measurements will be implemented using visible and near infrared LED and the photodetector in order to replace the spectrometer usage for soil spectroscopy. This would lead to achieve the primary objective of this research in developing a simple and low cost spectroscopy uses light-emitting diode (LED).

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