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Wang, Pei-Wen, Yu-Chiang Hung, Tung-Yi Lin, Jia-You Fang, Pei-Ming Yang, Mu-Hong Chen i Tai-Long Pan. "Comparison of the Biological Impact of UVA and UVB upon the Skin with Functional Proteomics and Immunohistochemistry". Antioxidants 8, nr 12 (20.11.2019): 569. http://dx.doi.org/10.3390/antiox8120569.
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The skin provides protection against external stimuli; however, solar radiation, including ultraviolet A (UVA) and ultraviolet B (UVB), can result in profound influences on skin structure and function, which eventually impairs its molecular characteristics and normal physiology. In the current study, we performed proteome tools combined with an immunohistological approach on nude mouse skin to evaluate the adverse responses elicited by UVA and UVB irradiation, respectively. Our findings indicated that UVA significantly promotes oxidative damage in DNA, the breakdown of collagen fiber in the dermis, and the apoptosis of fibroblasts, which leads to inflammation. Meanwhile, UVB administration was found to enhance the carbonylation of various proteins and the proliferation of keratinocyte. Particularly, raspberry extract, which has been confirmed to have antioxidative efficacy, could effectively attenuate ultraviolet (UV) radiation-caused cell death. Network analysis also implied that UVA and UVB induce quite different responses, and that UVA results in cell death as well as inflammation mediated by caspase-3 and activator protein 1/nuclear factor kappa-light-chain-enhancer of activated B cells (AP-1/NF-κB), while UVB predominantly increases the risk of skin carcinogenesis involved with oncogenes such as p53 and c-Myc. Taken together, functional proteomics coordinated with histological experiments could allow for a high-throughput study to explore the alterations of crucial proteins and molecules linked to skin impacts subjected to UVA and UVB exposure.
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Bowman, Robert L., Rebecca C. Hennessey, Tirzah J. Weiss, David A. Tallman, Emma R. Crawford, Brandon M. Murphy, Amy Webb i in. "UVB mutagenesis differs in Nras- and Braf-mutant mouse models of melanoma". Life Science Alliance 4, nr 9 (1.07.2021): e202101135. http://dx.doi.org/10.26508/lsa.202101135.
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BRAF-mutant melanomas are more likely than NRAS-mutant melanomas to arise in anatomical locations protected from chronic sun damage. We hypothesized that this discrepancy in tumor location is a consequence of the differential sensitivity of BRAF and NRAS-mutant melanocytes to ultraviolet light (UV)-mediated carcinogenesis. We tested this hypothesis by comparing the mutagenic consequences of a single neonatal, ultraviolet-AI (UVA; 340–400 nm) or ultraviolet-B (UVB; 280–390 nm) exposure in mouse models heterozygous for mutant Braf or homozygous for mutant Nras. Tumor onset was accelerated by UVB, but not UVA, and the resulting melanomas contained recurrent mutations affecting the RING domain of MAP3K1 and Actin-binding domain of Filamin A. Melanomas from UVB-irradiated, Braf-mutant mice averaged twice as many single-nucleotide variants and five times as many dipyrimidine variants than tumors from similarly irradiated Nras-mutant mice. A mutational signature discovered in UVB-accelerated tumors mirrored COSMIC signatures associated with human skin cancer and was more prominent in Braf- than Nras-mutant murine melanomas. These data show that a single UVB exposure yields a greater burden of mutations in murine tumors driven by oncogenic Braf.
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Marwood, Christopher A., Ralph EH Smith, John A. Furgal, Murray N. Charlton, Keith R. Solomon i Bruce M. Greenberg. "Photoinhibition of natural phytoplankton assemblages in Lake Erie exposed to solar ultraviolet radiation". Canadian Journal of Fisheries and Aquatic Sciences 57, nr 2 (1.02.2000): 371–79. http://dx.doi.org/10.1139/f99-258.
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Photoinhibition was examined in natural assemblages of phytoplankton from Lake Erie exposed to ambient solar radiation. The impacts on photosynthesis of photosynthetically active radiation (400-700 nm) (PAR), ultraviolet-A radiation (320-400 nm) (UVA), and ultraviolet-B radiation (295-320 nm) (UVB) were assessed at three sites on the lake using pulse amplitude modulated chlorophyll fluorescence. Short exposures (<= 30 min) to sunlight containing UVB (1.8-4.4 mmol·m-2) resulted in the rapid loss of up to 60% of photosystem II efficiency (in the dark-adapted state) (Fv/Fm) and quantum yield (in the light-adapted state) (ΔF/F'm). Exposure to UVA (46-105 mmol·m-2) generally diminished Fv/Fm and, to a lesser extent, ΔF/F'm. Short exposures to PAR (733-1588 mmol·m-2) had no significant effects on electron transport. Recovery from UVA- or UVB-induced photoinhibition was complete for Fv/Fm and 90% complete for ΔF/F'm after 2 h in low light. The results indicate that exposures of phytoplankton to surface radiation need only be short in duration to cause substantial UV inhibition of photosynthesis. However, depending on the kinetics of mixing of the water column, recovery of photosynthesis is possible if there is sufficient time for repair of UV damage. Future elevated levels of solar UVB due to ozone depletion could significantly inhibit primary production in mesotrophic lakes such as Lake Erie.
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Zocoler, Marcos Alberto, Joelma Vieira Lopes, Letícia Duarte dos Santos, Guilherme Luiz de Castro Carvalho i Décio Gomes de Oliveira. "DESENVOLVIMENTO, AVALIAÇÃO DO EFEITO FOTOPROTETOR UVA E UVB, AÇÃO ANTIOXIDANTE E ESTABILIDADE DE UM CREME COM EXTRATOS DE UMBÚ-CAJÁ". Colloquium Vitae 11, nr 3 (20.12.2019): 51–61. http://dx.doi.org/10.5747/cv.2019.v11.n3.v270.
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The objective of this studywas to evaluate the UVA and UVB photoprotective effect and the antioxidant activity of dermatological cream developed with umbu-cajá (Spondias sp) extracts. The antioxidant activity of the cream was evaluated by the 1,1-diphenyl-2-picrylhydrazine (DPPH) radical inhibition method in triplicate, and the dilutions were evaluated by spectrophotometer, with the absorbance values determined at 517 nm. The evaluation of UVB and UVB photoprotective capacity was performed according to Mansur method and determining the UVA / UVB ratio and the critical wavelength. The developed cream showed antioxidant activity with inhibition close to 80% at 10 mg.mL-1dilution. The spectrophotometer scan showed that the inputs and the cream can absorb ultraviolet light from 290 to 400 nm. The cream with umbu-cajá extract studied had antioxidant and photoprotective properties UVA / UVB and can be used as anti-aging cosmetic.
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Craver, Joshua K., Chad T. Miller, Kimberly A. Williams i Nora M. Bello. "Ultraviolet Radiation Affects Intumescence Development in Ornamental Sweetpotato (Ipomoea batatas)". HortScience 49, nr 10 (październik 2014): 1277–83. http://dx.doi.org/10.21273/hortsci.49.10.1277.
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Intumescences are a physiological disorder characterized by hypertrophy and possibly hyperplasia of plant tissue cells. Ultimately, this disorder results in the death of the affected cells. Previous observations and research suggest that the quality and quantity of light to which plants are exposed may be a factor in development of the disorder. The purpose of this study was to assess the preventive effect of ultraviolet-B (UVB) radiation on intumescence development in ornamental sweetpotato (Ipomoea batatas). Two sweetpotato cultivars, Sidekick Black and Ace of Spades, were grown under light treatments consisting of 1) normal greenhouse production conditions; 2) supplemental UVB lighting; 3) supplemental UVB lighting with Mylar® sleeves over the lamps to block UVB radiation; and 4) control lighting with full spectrum lamps. Treatments were administered for 2 weeks, and the experiment was repeated twice. ‘Ace of Spades’ was highly susceptible to intumescence development, whereas ‘Sidekick Black’ was much less susceptible to the disorder. For ‘Ace of Spades’, the addition of UVB radiation significantly reduced the number of leaves affected with intumescences when compared with plants grown under the other light treatments; this UVB effect was not apparent for ‘Sidekick Black’. Furthermore, there was no evidence for reduced plant growth under UVB light in either cultivar, but side effects from the radiation included leaf discoloration and deformities. This study indicates a cultivar-specific effect of UVB light in preventing intumescence development on ornamental sweetpotato, therefore suggesting a potential genetic component in intumescence susceptibility. These results provide further insight in better understanding intumescence development and how to prevent the disorder.
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Pirc, Matija, Simon Caserman, Polonca Ferk i Marko Topič. "Compact UV LED Lamp with Low Heat Emissions for Biological Research Applications". Electronics 8, nr 3 (21.03.2019): 343. http://dx.doi.org/10.3390/electronics8030343.
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Much biomedical research focuses on the effects of UV light on human cells. UV light sources are a prerequisite for such research. This paper presents the design and achieved performance of a UVA (Ultraviolet A: 320–400 nm) and a UVB (Ultraviolet B: 290–320 nm) LED-based lamp suitable for use in bioassays, as well as inside an incubator. Numerical simulations were used to optimise the number, layout and output power of LEDs to achieve good irradiance homogeneity while maintaining low costs. Design was optimised for the efficient transfer of generated heat away from the irradiated samples through the heatsink at the back of the lamps. The average irradiance of the target surface by the UVA lamp was 70.1 W/m2 with a maximum deviation of 4.9%, and the average irradiance by the UVB lamp was 3.1 W/m2 with a maximum deviation of 4.8%. With the UVA and UVB lamps, the temperature of samples undergoing irradiation in the incubator rises from 37 to 42 °C within 40 and 67 min, respectively. This by far exceeds the required UV irradiation time in most cases. Tests on Jurkat and HEK-293 cell cultures confirmed the suitability of our lamps for biomedical research.
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Deeg, HJ, L. Bazar, M. Sigaroudinia i M. Cottler-Fox. "Ultraviolet B light inactivates bone marrow T lymphocytes but spares hematopoietic precursor cells". Blood 73, nr 2 (1.02.1989): 369–71. http://dx.doi.org/10.1182/blood.v73.2.369.369.
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Abstract Bone marrow cells from ten normal donors were exposed to ultraviolet (UV)C or UVB light for total exposures of 0.1 to 100 mJ/cm2, and assayed for granulocyte-macrophage colony-forming units (CFU-GM), erythroid burst-forming units (BFU-E), and phytohemagglutinin (PHA)- stimulated proliferative responses. After exposure to UVC CFU-GM, BFU-E and PHA responses showed a UV dose-dependent sharp decrease to levels less than 1% of controls with 0.5, 2.0, and 10 mJ/cm2, respectively. With UVB, PHA responses were most sensitive, declining to less than 1% at 5 mJ/cm2. BFU-E decreased to less than 1% of control with 15 mJ/cm2 UVB. CFU-GM, at UVB doses of 0.1 to 2.0 mJ/cm2, increased to 125% to 130% of control and decreased to less than 1% only at exposures greater than 20 mJ/cm2. Thus, these studies show that UVB, but not UVC light, can be used to inactivate bone marrow T lymphocytes selectively while sparing hematopoietic precursor cells. The data suggest that UVB irradiation can be used for T-lymphocyte purging for allogeneic marrow transplantation.
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Deeg, HJ, L. Bazar, M. Sigaroudinia i M. Cottler-Fox. "Ultraviolet B light inactivates bone marrow T lymphocytes but spares hematopoietic precursor cells". Blood 73, nr 2 (1.02.1989): 369–71. http://dx.doi.org/10.1182/blood.v73.2.369.bloodjournal732369.
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Bone marrow cells from ten normal donors were exposed to ultraviolet (UV)C or UVB light for total exposures of 0.1 to 100 mJ/cm2, and assayed for granulocyte-macrophage colony-forming units (CFU-GM), erythroid burst-forming units (BFU-E), and phytohemagglutinin (PHA)- stimulated proliferative responses. After exposure to UVC CFU-GM, BFU-E and PHA responses showed a UV dose-dependent sharp decrease to levels less than 1% of controls with 0.5, 2.0, and 10 mJ/cm2, respectively. With UVB, PHA responses were most sensitive, declining to less than 1% at 5 mJ/cm2. BFU-E decreased to less than 1% of control with 15 mJ/cm2 UVB. CFU-GM, at UVB doses of 0.1 to 2.0 mJ/cm2, increased to 125% to 130% of control and decreased to less than 1% only at exposures greater than 20 mJ/cm2. Thus, these studies show that UVB, but not UVC light, can be used to inactivate bone marrow T lymphocytes selectively while sparing hematopoietic precursor cells. The data suggest that UVB irradiation can be used for T-lymphocyte purging for allogeneic marrow transplantation.
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Haag, Robin, Nicole Sieber i Martin Heßling. "Cataract Development by Exposure to Ultraviolet and Blue Visible Light in Porcine Lenses". Medicina 57, nr 6 (27.05.2021): 535. http://dx.doi.org/10.3390/medicina57060535.
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Background and Objectives: Cataract is still the leading cause of blindness. Its development is well researched for UV radiation. Modern light sources like LEDs and displays tend to emit blue light. The effect of blue light on the retina is called blue light hazard and is studied extensively. However, its impact on the lens is not investigated so far. Aim: Investigation of the impact of the blue visible light in porcine lens compared to UVA and UVB radiation. Materials and Methods: In this ex-vivo experiment, porcine lenses are irradiated with a dosage of 6 kJ/cm2 at wavelengths of 311 nm (UVB), 370 nm (UVA), and 460 nm (blue light). Lens transmission measurements before and after irradiation give insight into the impact of the radiation. Furthermore, dark field images are taken from every lens before and after irradiation. Cataract development is illustrated by histogram linearization as well as faults coloring of recorded dark field images. By segmenting the lens in the background’s original image, the lens condition before and after irradiation could be compared. Results: All lenses irradiated with a 6 kJ/cm2 reveal cataract development for radiation with 311 nm, 370 nm, and 460 nm. Both evaluations reveal that the 460 nm irradiation causes the most cataract. Conclusion: All investigated irradiation sources cause cataracts in porcine lenses—even blue visible light.
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Setaluri, Vijay, Adele R. Clark i Steven R. Feldman. "Transmittance Properties of Flurandrenolide Tape for Psoriasis: Helpful Adjunct to Phototherapy". Journal of Cutaneous Medicine and Surgery 4, nr 4 (październik 2000): 196–98. http://dx.doi.org/10.1177/120347540000400404.
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Background: Flurandrenolide tape is a valuable agent in the treatment of lichen simplex chronicus and in psoriasis. The corticosteroid is helpful for reducing the symptoms and induration of the lichen simplex chronicus lesion, and occlusion of the lesion with the tape reduces the patient's opportunity to rub and scratch the affected area. Objective: The purpose of this study was to determine to what extent flurandrenolide tape may block ultraviolet (UV) light and interfere with phototherapy of psoriasis. Methods: Flurandrenolide tape was applied to quartz spectroscopy cuvettes, and the absorption spectrum was determined using a Beckman DU-600 spectrophotometer. The effect of the tape on UV light transmission was also determined using our UVA-UVB office phototherapy unit. Results: Flurandrenolide tape has considerable UV absorption in the UVC range with less absorption in the UVB and UVA range. The transmittance is greater (less absorption) with longer wavelengths. There was greater UV absorption in the UVB range than in the UVA range. Conclusion: Although flurandrenolide tape may be left in place during PUVA therapy, adjustment of UV dose or removal of the tape is probably needed during UVB phototherapy.
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Xu, Fei, i Jaroslav Vostal. "Vitamin K3 Is a Potential Ultraviolet Photosensitizer for Pathogen Reduction of Human Platelets and Plasma". Blood 120, nr 21 (16.11.2012): 3434. http://dx.doi.org/10.1182/blood.v120.21.3434.3434.
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Abstract Abstract 3434 Human platelets are stored up to 5 days at room temperature and may support bacterial growth before transfusion. Transfusion of bacterially contaminated platelets remains the highest transfusion transmitted infectious disease risk today. One approach to reducing this risk is the development of safe and effective pathogen reduction methodologies. We evaluated UV light (A and B) with vitamin K3 (VK3) as a photosensitizer for efficacy in reducing bacterial growth in platelet concentrates and plasma. Six species of bacteria, including Bacillus cereus, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Klebsiella pneumoniae and Escherichia coli, were spiked respectively into phosphate buffered saline (PBS) buffer and exposed to UVA irradiation before bacterial growth was determined. As shown in Figure 1, the bacterial colony forming units (CFU) were reduced with increasing VK3 concentrations and UVA dosages. The VK3 at 400 uM plus UVA-radiation (2.88 J/cm2) significantly reduced the bacterial CFU in PBS spiked with bacteria. The same six-bacteria panel were spiked respectively into platelet concentrates (PCs) diluted with platelet additive solution and mixed with 400 uM VK3 before the UVA irradiation. As shown in Fig 2a, the bacteria CFU were reduced with increasing dosage of UVA but efficacy declined with lower dilution of PCs. At VK3 concentration of 400 uM and PC diluted to 20% a UVA-dose of 5.76 J/cm2 significantly reduced bacterial CFUs in PCs spiked with E coli, K pneumoniae, P aeruginosa and S epidermidis respectively. Similar results were obtained with the same six-bacteria panel spiked into plasma as shown in Fig 2b. UVB and VK3 combination had a biphasic inhibitory effect as shown in Fig 3. The VK3 at 200 uM plus UVB-radiation (0.015 J/cm2) also significantly reduced the CFU from the same six-bacteria panel spiked into PBS. However higher concentrations of 1600 uM VK3 could partially reverse the bacterial growth inhibition under UVB-radiation at 0.0038, 0.0075, and 0.015 J/cm2 for E coli, K pneumoniae and S aureus bacterial organisms. These findings suggest that VK3 may serve as an effective UVA photosensitizer for pathogen reduction of human platelets. With UVB light, lower concentrations of VK3 are effective at inhibiting bacterial proliferation but higher concentrations of VK3 may serve as a weak UVB blocker. Additional studies will need to be conducted to determine the impact of UV light and VK3 on platelet in vitro and in vivo performance. “This abstract reflects the views of the author and should not be construed to represent FDA's views or policies.” Disclosures: No relevant conflicts of interest to declare.
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Fleury, Naomi, Martin Feelisch, Prue H. Hart, Richard B. Weller, Jordan Smoothy, Vance B. Matthews i Shelley Gorman. "Sub-erythemal ultraviolet radiation reduces metabolic dysfunction in already overweight mice". Journal of Endocrinology 233, nr 1 (kwiecień 2017): 81–92. http://dx.doi.org/10.1530/joe-16-0616.
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Exposure to sunlight may limit cardiometabolic risk. In our previous studies, regular exposure to sub-erythemal (non-burning) ultraviolet radiation (UVR) reduced signs of adiposity and cardiometabolic dysfunction in mice fed a high-fat diet. Some of the observed effects were dependent on skin release of nitric oxide after UVR exposure. Here, we examine the effects of sub-erythemal UVR on signs of adiposity and metabolic dysfunction in already overweight mice, comparing the effects of two sunlamps with distinct emitted light spectra. Mice were fed a high-fat diet from 8 weeks of age, with UVR administered twice a week from 14 weeks of age until they were killed at 20 weeks of age. Mice were irradiated with the same dose of UVB radiation (1 kJ/m2) from either FS40 (65% UVB, 35% UVA) or CLEO (4% UVB, 96% UVA) sunlamps, but substantially more UVA from the latter. FS40 UVR (but not CLEO UVR) significantly reduced mouse weights and weight gain, compared to mice fed a high-fat diet (only). These effects were dependent on nitric oxide. Conversely, CLEO UVR (but not FS40 UVR) significantly reduced circulating LDL cholesterol. Both light sources reduced fasting insulin levels, and the extent of hepatic steatosis; the latter was reversed by topical application of cPTIO, suggesting an important role for skin release of nitric oxide in preventing hepatic lipid accumulation. These results suggest that there may be a number of benefits achieved by regular exposure to safe (non-burning) levels of sunlight or UV-containing phototherapy, with effects potentially dependent on the predominance of the wavelengths of UVR administered.
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Park, Dae-Hwan, Seung-Taek Oh i Jae-Hyun Lim. "Development of UVB LED Lighting System Based on UV Dose Calculation Algorithm to Meet Individual Daily UV Dose". Applied Sciences 9, nr 12 (18.06.2019): 2479. http://dx.doi.org/10.3390/app9122479.
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Ultraviolet B (UVB) in sunlight is known to promote health when humans are exposed to optimum sunlight. Proper exposure to ultraviolet B is essential to produce vitamin D in the body, which is a particularly important factor for health. However, there has been an increase recently in the number of people who are lacking sunlight exposure due to staying indoors. Avoiding ultraviolet (UV) rays leads to health deterioration. To solve this problem, a portable ultraviolet measuring device that provides users with the UV intensity information of outdoor sunlight has been developed while UVB Light Emitting Diode (LED) lighting technologies capable of providing UVB radiation have been studied. However, existing technologies are mere methods for providing information on ultraviolet rays and artificially exposing to ultraviolet rays, and there is a risk for the UV radiation amount to not meet the daily required UV dose. Therefore, in this paper, a UVB LED general lighting system based on a UV exposure calculation algorithm that supports users’ daily required UV dose is proposed. The proposed system is composed of an IoT (Internet of Things) UV measuring device that measures the UV dose indoors, as well as outdoors, UVB LED general lighting which can safely provide UVB doses at indoors, and a smartphone which provides information on the cumulative UV dose and the estimated amount of vitamin D while it controls UVB LED general lighting. In addition, it is possible to support users’ vitamin D synthesis by providing as much UV light as its shortage through UVB LED general lighting, based on an individual’s UV exposure amount through outdoor sunlight, using a smartphone implementing a UV dose calculation algorithm. In order to confirm the performance of the proposed system, a simulation was conducted assuming that users with skin types 2 and 3 performed outdoor activities within 30 min and entered the room. The result confirmed that the proposed lighting can provide users of all ages with the UV dose required per day.
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Ozawa, Maki, Katalin Ferenczi, Toyoko Kikuchi, Irma Cardinale, Lisa M. Austin, Todd R. Coven, Lauren H. Burack i James G. Krueger. "312-nanometer Ultraviolet B Light (Narrow-Band UVB) Induces Apoptosis of T Cells within Psoriatic Lesions". Journal of Experimental Medicine 189, nr 4 (15.02.1999): 711–18. http://dx.doi.org/10.1084/jem.189.4.711.
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Narrow-band (312 nm) ultraviolet B light (UVB) is a new form of therapy for psoriasis, but its mechanism of action is unknown. In a bilateral comparison clinical study, daily exposure of psoriatic plaques to broad-band UVB (290–320 nm) or 312-nm UVB depleted T cells from the epidermis and dermis of psoriatic lesions. However, 312-nm UVB was significantly more depleting in both tissue compartments. To characterize the mechanism of T cell depletion, assays for T cell apoptosis were performed on T cells derived from UVB-irradiated skin in vivo and on T cells irradiated in vitro with 312-nm UVB. Apoptosis was induced in T cells exposed to 50–100 mJ/cm2 of 312-nm UVB in vitro, as measured by increased binding of fluorescein isothiocyanate (FITC)–Annexin V to CD3+ cells and by characteristic cell size/granularity changes measured by cytometry. In vivo exposure of psoriatic skin lesions to 312-nm UVB for 1–2 wk also induced apoptosis in T cells as assessed by the terminal deoxynucleotidyl transferase–mediated dUTP-biotin nick end labeling (TUNEL) reaction in tissue sections, by binding of FITC–Annexin V to CD3+ T cells contained in epidermal cell suspensions, and by detection of apoptosis-related size shifts of CD3+ cells. Induction of T cell apoptosis could be the main mechanism by which 312-nm UVB resolves psoriasis skin lesions.
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Hassan, Snur M. A., Adel J. Hussein i Azad K. Saeed. "Role of Green Tea in Reducing Epidermal Thickness upon Ultraviolet Light-B Injury in BALB/c Mice". Advances in Biology 2015 (1.10.2015): 1–6. http://dx.doi.org/10.1155/2015/890632.
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The main environmental source for skin damage is ultraviolet (UV) radiation. Many adverse effects have been recognized as the result of prolonged cutaneous exposure to solar ultraviolet radiation, such as erythema, edema, apoptosis, hyperplastic responses, photo-aging, and skin cancer development. Green tea provides photo-protection against UV radiation through many mechanisms including anti-inflammatory, immunomodulatory, and antioxidant properties. The aim of this study was to evaluate the effect of green tea in reducing epidermal thickness on mouse’s skin exposed to UVB irradiation. Thirty mice (Mus musculus species, BALB/c strain) underwent this study and were divided into 3 groups: control group (n=10 mice), without UVB exposure and green tea administration; exposure group (n=10 mice), which were exposed to UVB light only; and treatment group (n=10 mice), which were exposed to UVB light and treated with 1 mL of green tea through oral gavage. Mice from both groups (exposure and treatment) were subjected to UVB irradiation 4 days/week (20 minutes/day, 4 weeks). It concluded that oral administration of green tea was provided photo-protection against UVB induced hyperplasia; therefore, it can be regarded as a natural alternative for photo-protection.
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Boccumini, Louis E., Cynthia L. Fowler, Theresa A. Campbell, Linda F. Puertolas i Kays H. Kaidbey. "Photoreaction Potential of Orally Administered Levofloxacin in Healthy Subjects". Annals of Pharmacotherapy 34, nr 4 (kwiecień 2000): 453–58. http://dx.doi.org/10.1345/aph.18134.
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OBJECTIVE: To evaluate the photoreaction potential of levofloxacin on exposure to solar-simulating radiation. Solar-simulating is ultraviolet (UV) light, defined as UVA in the 320–400 nm range and UVB in the 290–320 nm range. DESIGN: In a single-center, double-blind, randomized study, 30 adults (20 men, 10 women) received oral levofloxacin (500 mg qd x 5 d) or placebo. At baseline photoexposure prior to drug administration, each subject was exposed to UVB light at 0.75, 1.0, and 2.0 times the minimal erythema dose and to UVA light (25 J/cm2). Photoexposure was repeated on day 5, two hours following final drug administration, and response was determined using both a photoreaction rating scale and investigator assessment. RESULTS: Using the photoreaction rating scale, following UVB exposure on day 5, no abnormal photoreactions were observed among levofloxacin recipients. UVA exposure was associated with mild reactions in 20 of 24 levofloxacin-treated and three of six placebo-treated subjects, with no associated symptoms. By investigator assessment, all subjects had a negative reaction to UVB photoexposure, and 10 of 24 levofloxacin-treated and three of six placebo-treated subjects had a photoreaction following UVA photoexposure. Dermal reactions were mild and similar for both treatment groups. No subject experienced an immediate wheal-and-flare reaction. There were no statistically significant differences between treatment groups for any of the comparisons. CONCLUSIONS: Levofloxacin has a low photosensitizing potential when administered to healthy subjects.
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Nunes, Alesandra R., Ícaro G. P. Vieira, Dinalva B. Queiroz, Antonio Linkoln Alves Borges Leal, Selene Maia Morais, Débora Feitosa Muniz, João Tavares Calixto-Junior i Henrique Douglas Melo Coutinho. "Use of Flavonoids and Cinnamates, the Main Photoprotectors with Natural Origin". Advances in Pharmacological Sciences 2018 (28.11.2018): 1–9. http://dx.doi.org/10.1155/2018/5341487.
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Many pathological problems are initiated by ultraviolet radiation (UVR), such as skin cancer, the most commonly diagnosed cancer worldwide. The UVA (320–400 nm) and UVB (290–320 nm) wavelengths may cause effects such as photoaging, DNA damage, and a series of cellular alterations. The UVA radiation can damage the DNA, oxidize the lipids, and produce dangerous free radicals, which can cause inflammation, modify the gene expression in response to stress, and weaken the skin immune response. With a minor penetration, the UVB radiation is more harmful, being responsible for immediate damage. Ultraviolet radiation light emitted by the sun is considered necessary for the existence of life but cause radiation problems, especially in the skin. The photoprotective activities of plant extracts and isolated composts were evaluated by many reports, as well as the correlation of these compounds with the antioxidant activity. This review presents plant compounds with interest to the cosmetic industry to be used in sunscreens such as flavonoids and cinnamates.
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Serafini, Mairim Russo, Cassia Britto Detoni, Paula dos Passos Menezes, Rose Nely Pereira Filho, Vanessa Silveira Fortes, Maria José Fonseca Vieira, Sílvia Stanisçuaski Guterres, Ricardo Luiz Cavalcanti de Albuquerque Junior i Adriano Antunes de Souza Araújo. "UVA-UVB Photoprotective Activity of Topical Formulations ContainingMorinda citrifoliaExtract". BioMed Research International 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/587819.
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Exposure to solar radiation, particularly its ultraviolet (UV) component, has a variety of harmful effects on human health. Some of these effects include sunburn cell formations, basal and squamous cell cancers, melanoma, cataracts, photoaging of the skin, and immune suppression. The beneficial photoprotective effects of topical formulations with the extract,Morinda citrifolia, have not been investigated. This present study aims to investigate the potential benefits ofM. citrifoliatopical application on the dorsal skin of mice, exposed to UVA-UVB light. Using 7 days of treatment, [before (baseline values) and 20 h after UV exposure], the thickness, skin barrier damage (TEWL), erythema, and histological alterations were evaluated. The results showed that the formulations containing the extract protected the skin against UV-induced damage.
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Holtby, L. Blair, i Max L. Bothwell. "Effects of solar ultraviolet radiation on the behaviour of juvenile coho salmon (Oncorhynchus kisutch): avoidance, feeding, and agonistic interactions". Canadian Journal of Fisheries and Aquatic Sciences 65, nr 4 (1.04.2008): 701–11. http://dx.doi.org/10.1139/f08-013.
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The behaviour of juvenile coho salmon (Oncorhynchus kisutch) was observed in outdoor experimental flumes in which three different spectral regimes were created by plastic covers that selectively blocked all or portions of natural ultraviolet radiation (UVR). The three light treatments were (i) photosynthetically active radiation (PAR, 400–700 nm), (ii) PAR plus longer wavelength ultraviolet (PAR + UVA, 320–700 nm), and (iii) full-spectrum sunlight with both long and short wavelength ultraviolet included (PAR + UVA + UVB, 280–700 nm). Observations made at different times of the day and under both overcast and sunny skies allowed an assessment of PAR intensity on behaviour in addition to that of UVR. We quantified shade-seeking behaviour, feeding strikes, and agonistic interactions (approaches, chases, and nips) between individuals. Under higher PAR intensities, a greater proportion of juvenile coho tended to take cover under rocks. Shade-seeking behaviour increased significantly in the presence of UVR. Feeding and agonistic interactions were partially inhibited at higher PAR intensities and very significantly depressed by UVR. For all behaviours tested, the effects were mediated by UVA with no significant additional impacts from UVB. UVR-mediated effects on behaviour could have ecological consequences through influencing summer densities, density-dependent growth, and size-dependent winter and early marine survivals.
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Yousefi, Hossein, Samira Mohammadzadeh, Arsalan Irompour, Neda Shenasifam, Elham Roshandel i Arsalan Jalili. "Overall study on molecular pathways of skin cancer derived from Ultra- violet radiation as an environmental threat". Environment Conservation Journal 16, SE (5.12.2015): 547–55. http://dx.doi.org/10.36953/ecj.2015.se1665.
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An important part of solar radiation is considered to be Ultraviolet radiation. Though through passing ozone layer it is progressively filtered. Due to the depletion of the ozone layer, the filtering activity of the latter is reduced and as a result more UV radiation, UVB in particular, reaches the Earth’s surface. Ultraviolet radiation is composed of three different wavelengths: UVA, UVB and UVC. Although UVC isn't a cause of skin cancer, UVA and UVB play different roles as for tanning, burning, and photo aging. As a matter of fact, Ultraviolet light can damage DNA in the epidermis. However, through apoptosis the damaged DNA is repaired or deleted in order to prevent the generation of cancer. It is believed that a deficient apoptotic mechanism might make individuals liable to skin cancer. The main factor for generating skin cancer is considered to be the UV radiation which could cause basal cell carcinoma, squamous cell carcinoma and possibly melanoma. For the maintenance of hemostasis, apoptosis plays a key role. This is done via many molecular pathways such as the pathways of tumor suppressor genes like P53, P21 and also the expression of BAX proteins. These pathways are involved in apoptosis after UV radiation. It is clear that the malfunction of these genes and proteins can lower the tolerance of body and cause cancer. The goal of this article is to investigate the molecular pathways of skin cancer derived from Ultra violet radiation as an environmental threat.
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Maeda, Tomoko, Chunhai Hao i Victor A. Tron. "Ultraviolet Light (UV) Regulation of the TNF Family Decoy Receptors DcR2 and DcR3 in Human Keratinocytes". Journal of Cutaneous Medicine and Surgery 5, nr 4 (lipiec 2001): 294–98. http://dx.doi.org/10.1177/120347540100500402.
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Background: Several additional members of the tumor necrosis factor (TNF) receptor family were recently identified. The existence of such receptors, which may play distinct and unique regulatory roles, suggests that complex regulatory mechanisms are involved in apoptosis. Objective: This study examines the expression of several members of the TNF receptor family in human keratinocytes exposed to ultraviolet B (UVB) irradiation. Methods: Human keratinocytes were exposed to increasing doses of UVB, total RNA was harvested, and a quantitative RNase protection assay was performed. Results: Decoy receptor-3 (DcR3), a nonfunctional receptor that binds to Fas ligand (FasL), was constitutively expressed at high level in keratinocytes but decreased rapidly in cells exposed to UVB. Decoy receptor-2 (DcR2), a nonfunctional receptor that binds to TNF-related apoptosis-inducing ligand (TRAIL)/APO-2L, showed the opposite expression pattern. DcR2 was undetectable in unirradiated keratinocytes and was markedly up-regulated after exposure to UVB. Although the response showed significant delays at higher UVB doses, the patterns observed for DcR3 and DcR2 were consistent in this set of experiments. Conclusion: We conclude that UVB regulates expression of these two TNF decoy receptors in keratinocytes. This pathway may represent a novel mechanism for regulation of apoptosis in the skin.
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Lian, Yu, Lei Mai, Nancy Cromar, Neil Buchanan, Howard Fallowfield i Xiaoming Li. "MS2 coliphage and E. coli UVB inactivation rates in optically clear water: dose, dose rate and temperature dependence". Water Science and Technology 78, nr 10 (11.12.2018): 2228–38. http://dx.doi.org/10.2166/wst.2018.509.
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Abstract Natural ultraviolet irradiance disinfection is known to play a significant role in both natural wastewater treatment systems and drinking water disinfection processes, while the influence of ultraviolet B (UVB) delivering method on sunlight disinfection outcome is still unclear. This study aims to determine the effects of environmentally relevant temperatures, UVB doses (J m−2) and dose rates (W m−2) on the inactivation and log reduction values (LRVs) of the F-RNA coliphage MS2 and Escherichia coli in optically clear water. E. coli and MS2 were separately incubated and irradiated at five different doses of UVB light that delivered using six UVB dose rates. The results of the study demonstrate that the UVB dose delivering method (combination of dose rate and exposure time) influences inactivation and LRVs of E. coli and MS2 at all UVB doses investigated (up to seven-fold difference). Two phases were identified within the UVB dose rate, UVB inactivation or LRV curves for both organisms; a UVB dose rate limited inactivation phase and a dose rate saturation inactivation phase. The results contribute to a better understanding of UVB disinfection in the environment and natural wastewater treatment systems, potentially improving the design and operation of high rate algal ponds.
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Song, Han Sung, Young Jin Yoo, Gil Ju Lee, Ki Soo Chang i Young Min Song. "Optical Design of Porous ZnO/TiO2 Films for Highly Transparent Glasses with Broadband Ultraviolet Protection". Journal of Nanomaterials 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/2738015.
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We present a design of a bilayer porous film structure on a glass substrate for the highly efficient ultraviolet (UV) protection with high visible-light transparency. To effectively block UVB (280–315 nm) and UVA (315–400 nm), titanium dioxide (TiO2) and zinc oxide (ZnO) are used as absorbing layers having the appropriate coverages in different UV ranges with extinction coefficients, respectively. We show the process of refractive index (RI) matching by controlling porosity (Pr). Effective RIs of porous media with TiO2 and ZnO were calculated based on volume averaging theory. Transmittances of the designed films with different effective RIs were calculated using rigorous coupled-wave analysis method. Using admittance loci method, the film thickness was optimized in center wavelengths from 450 to 550 nm. The results show that the optimal design provides high UV shielding performance at both UVA and UVB with high transparency in the visible range. We also analyze electrical field distributions in each layer and angle dependency with 3D HSV color map.
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Ortega-Retuerta, E., U. Passow, C. M. Duarte i I. Reche. "Effects of ultraviolet B radiation on (not so) transparent exopolymer particles". Biogeosciences 6, nr 12 (17.12.2009): 3071–80. http://dx.doi.org/10.5194/bg-6-3071-2009.
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Abstract. Transparent exopolymer particles (TEP) are the most ubiquitous gel particles in the ocean and form abiotically from dissolved precursors. Although these particles can accumulate at the ocean surface, being thus exposed to intense sunlight, the role of solar radiation for the assembly and degradation of TEP is unknown. In this study, we experimentally determined the effects of visible and ultraviolet B (UVB) radiation on (1) TEP degradation (photolysis experiments), (2) TEP assembly from dissolved polymers (photoinhibition experiments) and (3) TEP release by microorganisms. Solar radiation, particularly in the UVB range, caused significant TEP photolysis, with loss rates from 27 to 34% per day. Dissolved polysaccharides did not increase in parallel. No TEP were formed under UVB, visible or dark conditions, indicating that light does not promote TEP assembly. UVB radiation enhanced TEP release by microorganisms, possibly due to cell deaths, or as a protective measure. Increases in UVB may lead to enhanced TEP photolysis in the ocean, with further consequences for TEP dynamics and, ultimately, sea-air gas exchange.
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Ortega-Retuerta, E., U. Passow, C. M. Duarte i I. Reche. "Effects of ultraviolet B radiation on (not so) transparent exopolymer particles". Biogeosciences Discussions 6, nr 4 (28.07.2009): 7599–625. http://dx.doi.org/10.5194/bgd-6-7599-2009.
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Abstract. Transparent exopolymer particles (TEP) are the most ubiquitous gel particles in the ocean and form abiotically from dissolved precursors. Although these particles can accumulate at the ocean surface, being thus exposed to intense sunlight, the role of solar radiation on the assembly and degradation of TEP is unknown. In this study, we experimentally determined the effects of visible and ultraviolet B (UVB) radiation on (1) TEP degradation (photolysis experiments), (2) TEP assembly from dissolved polymers (photoinhibition experiments) and (3) TEP release by microorganisms. Solar radiation, particularly in the UVB range, caused significant TEP photolysis, with loss rates from 27 to 34% per day. Dissolved polysaccharides did not increase in parallel. No TEP were formed under UVB, visible or dark conditions, indicating that light does not promote TEP assembly. UVB radiation enhanced TEP release by microorganisms, possibly due to cell deaths, or as a protective measure. Increases in UVB may lead to enhanced TEP photolysis in the ocean, with further consequences for TEP dynamics and, ultimately, sea-air gas exchange.
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Cornaghi, Laura, Francesca Arnaboldi, Rossella Calò, Federica Landoni, William Franz Baruffaldi Preis, Laura Marabini i Elena Donetti. "Effects of UV Rays and Thymol/Thymus vulgaris L. Extract in an ex vivo Human Skin Model: Morphological and Genotoxicological Assessment". Cells Tissues Organs 201, nr 3 (2016): 180–92. http://dx.doi.org/10.1159/000444361.
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Ultraviolet (UV) radiation is the major environmental factor affecting functions of the skin. Compounds rich in polyphenols, such as Thymus vulgaris leaf extract and thymol, have been proposed for the prevention of UV-induced skin damage. We compared the acute effects induced by UVA and UVB rays on epidermal morphology and proliferation, cytotoxicity, and genotoxicity. Normal human skin explants were obtained from young healthy women (n = 7) after informed consent and cultured at the air-liquid interface overnight. After 24 h, the samples were divided in 2 groups: the former exposed to UVA (16 or 24 J/cm2) and the latter irradiated with UVB (0.24 or 0.72 J/cm2). One hour after the end of irradiation, supernatants were collected for evaluation of the lactate dehydrogenase activity. Twenty-four hours after UVB exposure, biopsies were processed for light and transmission electron microscopy analysis, proliferation, cytotoxicity, and genotoxicity. UVB and UVA rays induced early inhibition of cell proliferation and DNA damage compared to controls. In particular, UVB rays were always more cytotoxic and genotoxic than UVA ones. For this reason, we evaluated the effect of either T. vulgaris L. extract (1.82 µg/ml) or thymol (1 µg/ml) on all samples treated for 1 h before UVB irradiation. While Thymus had a protective action for all of the endpoints evaluated, the action of the extract was less pronounced on epidermal proliferation and morphological features. The results presented in this study could be the basis for investigating the mechanism of thymol and T. vulgaris L. extract against the damage induced by UV radiation.
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Wei, Yongxiang, Weichao Zheng, Baoming Li, Qin Tong, Haipeng Shi i Xuanyang Li. "Effects of B-Wave Ultraviolet Supplementation Using Light-Emitting Diodes on Caged Laying Hens during the Later Phase of the Laying Cycle". Animals 10, nr 1 (19.12.2019): 15. http://dx.doi.org/10.3390/ani10010015.
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Caged laying hens are prone to calcium deficiencies, resulting in osteoporosis and egg quality deterioration during the later phase of the laying cycle. Fluorescent light and light-emitting diodes (LEDs), which are widely used in poultry houses now, are both deficient in ultraviolet (UV) light, the lack of which is detrimental to chickens’ welfare and health. This study was conducted to investigate the effects of UVB light supplementation using LEDs on the bone traits, blood parameters, laying performance, and egg quality for caged laying hens at 68–75 weeks. In total, 120 Jingfen laying hens were randomly assigned to four different groups, with three replicates in each group (10 hens in each cage as a replicate). UVB-LED lamps installed under the feed troughs were used to provide UVB light (296–316 nm) for the birds in the three treatment groups (1 h, 2 h, and 3 h UVB supplementation per day, respectively), while the control group was not exposed to UVB-LED light. Bone traits, egg quality, and amounts of calcium (Ca), phosphorus (P), 25-hydroxyvitamin D3 (25(OH)D3), 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), and 7-dehydrocholesterol (7-DHC) in both the serum and egg yolks were tested during the experiment. The results demonstrated that UVB-LED exposure significantly increased the bone mineral density (BMD), egg production, and yolk 1,25(OH)2D3 concentrations (p < 0.05), and reduced the content of serum 7-DHC (p < 0.05), especially in the 2 h/day group; however, it did not improve egg quality, vitamin D metabolites, or photoproducts in the serum and yolk 25(OH)2D3 concentrations (p > 0.05). This study concluded that UVB supplementation using LEDs had a positive effect on caged laying hens during the later phase of the laying cycle.
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Hu, Linping, Can Yang, Lina Zhang, Jing Feng i Wanpeng Xi. "Effect of Light-Emitting Diodes and Ultraviolet Irradiation on the Soluble Sugar, Organic Acid, and Carotenoid Content of Postharvest Sweet Oranges (Citrus sinensis (L.) Osbeck)". Molecules 24, nr 19 (22.09.2019): 3440. http://dx.doi.org/10.3390/molecules24193440.
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Mature ‘Hamlin’ sweet oranges (Citrus sinensis (L.) Osbeck) were irradiated using light-emitting diodes (LEDs) and ultraviolet (UV) light for six days after harvest. Based on evaluation of the basic ripening parameters of fruits, the contents of soluble sugars, organic acids, and carotenoids were analyzed (in pulps) on the sixth day by high-performance liquid chromatography (HPLC). The results showed that LED and UV irradiation not only accelerated orange ripening but also caused significant changes in the soluble sugar, organic acid, and carotenoid content. Compared with fruit subjected to dark shade (DS) treatment, the total soluble sugar, fructose, and glucose contents increased significantly in UV-treated (UVA, UVB, and UVC) fruits, while the sucrose content increased remarkably in white light, UVB, and UVC-treated fruits (p < 0.05). UV treatment was associated with inducing the largest effect on the total soluble sugar content. Except for UVB, other types of light notably induced an accumulation of the total organic acid content, none but blue light and red light markedly induced citric acid accumulation (p < 0.05). Interestingly, only the red light and dark shade treatments had markedly positive effects in terms of inducing carotenoid accumulation, including the total carotenoid, isolutein, zeaxanthin, lutein, neoxanthin, all-trans-violaxanthin, phytofluene, cis-ζ-carotene, and β-carotene concentrations. Other light treatments had significantly negative effects on carotenoid accumulation (p < 0.05). Therefore, soluble sugar, organic acid, and carotenoid accumulation in sweet oranges vary depending on the levels of UV and LED irradiation. Appropriate light irradiation is a potentially effective way to maintain or improve postharvest fruit quality.
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Lease, Kevin A., i Chris Papageorgio. "Bioinformatic Prediction of Ultraviolet Light Mutagenesis Sensitivity of Human Genes and a Method for Genetically Engineering UVB Resistance". Cancer Informatics 10 (styczeń 2011): CIN.S6670. http://dx.doi.org/10.4137/cin.s6670.
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Living on earth, we are exposed to ultraviolet (UV) light as part of the solar radiation. UVB spectrum light exposure contributes to the development of skin cancer by interacting with pyrimidine pairs to create lesions called cyclobutane pyrimidine dimers. If these lesions are not removed by nucleotide excision repair, they often give rise to C to T transition mutations. Based on these observations, a bioinformatics approach was used to predict the vulnerability of human protein coding genes to UVB induced loss of function mutations. This data was used to evaluate in depth those genes associated with malignant melanoma. In addition, we demonstrate a method of genetically engineering genes that significantly improves resistance to UVB loss of function mutations.
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Bok, Michael J., Nicholas W. Roberts i Thomas W. Cronin. "Behavioural evidence for polychromatic ultraviolet sensitivity in mantis shrimp". Proceedings of the Royal Society B: Biological Sciences 285, nr 1884 (sierpień 2018): 20181384. http://dx.doi.org/10.1098/rspb.2018.1384.
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Stomatopod crustaceans are renowned for their elaborate visual systems. Their eyes contain a plethora of photoreceptors specialized for chromatic and polarization detection, including several that are sensitive to varying wavelength ranges and angles of polarization within the ultraviolet (UV) range (less than 400 nm). Behavioural experiments have previously suggested that UV photoreception plays a role in stomatopod communication, but these experiments have only manipulated the entire UV range. Here, using a behavioural approach, we examine UV vision in the stomatopod Haptosquilla trispinosa . Using binary trained choice assays as well as innate burrow-choice experiments, we assessed the ability of H. trispinosa to detect and respond to narrow-band LED stimuli peaking near 314 nm (UVB) versus 379 nm (UVA) in wavelength. We find that H. trispinosa can discriminate these stimuli and appears to display an aversive reaction to UVB light, suggesting segregated behavioural responses to stimuli within the UV range. Furthermore, we find that H. trispinosa can discriminate stimuli peaking near 379 nm versus 351 nm in wavelength, suggesting that their wavelength discrimination in the UV is comparable to their performance in the human-visible range.
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Epstein, John H. "The potential cutaneous effects of stratospheric ozone depletion". Environmental Reviews 4, nr 1 (1.01.1996): 1–7. http://dx.doi.org/10.1139/a96-001.
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Recent evidence indicates that there has been a reduction in the stratospheric ozone over the northern hemisphere, as well as the Antarctic and Arctic latitudes. This has resulted in an increased penetration of ultraviolet B (UVB) at least as measured at Toronto, Canada, since 1989. If no precautions are observed by the human population, this could eventually result in an increase in the skin cancer incidence. This would be especially true for the most common cancers, that is, the nonmelanoma skin cancers (NMSCs), basal cell carcinomas and squamous cell carcinomas. In addition it has been predicted that the third most common skin cancer, the malignant melanoma, would also increase in incidence. However, the relationship between UVB radiation and melanoma formation is much less clear than it is for NMSCs. Clinically people with a loss or lack of melanin protection such as those with occulocutaneous albinism and vitiligo, or much more commonly, people with light skin, eyes, and hair would be at greatest risk. Also increased UVB penetration could exacerbate certain infections such as herpes simplex. People with UVB-sensitive diseases including solar urticaria, polymorphous light eruptions, lupus erythematosus, dermatomyositis, pemphigus, pemphigoid, Darier's disease, familial benign chronic pemphigus, and certain recessive degenerative genodermatoses would also be potentially more vulnerable.Key words: ozone, ultraviolet B (UVB), skin cancer, photosensitive skin diseases.
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Piao, Mei, Kyoung Kang, Ao Zhen, Hee Kang, Young Koh, Bong Kim i Jin Hyun. "Horse Oil Mitigates Oxidative Damage to Human HaCaT Keratinocytes Caused by Ultraviolet B Irradiation". International Journal of Molecular Sciences 20, nr 6 (25.03.2019): 1490. http://dx.doi.org/10.3390/ijms20061490.
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Horse oil products have been used in skin care for a long time in traditional medicine, but the biological effects of horse oil on the skin remain unclear. This study was conducted to evaluate the protective effect of horse oil on ultraviolet B (UVB)-induced oxidative stress in human HaCaT keratinocytes. Horse oil significantly reduced UVB-induced intracellular reactive oxygen species and intracellular oxidative damage to lipids, proteins, and DNA. Horse oil absorbed light in the UVB range of the electromagnetic spectrum and suppressed the generation of cyclobutane pyrimidine dimers, a photoproduct of UVB irradiation. Western blotting showed that horse oil increased the UVB-induced Bcl-2/Bax ratio, inhibited mitochondria-mediated apoptosis and matrix metalloproteinase expression, and altered mitogen-activated protein kinase signaling-related proteins. These effects were conferred by increased phosphorylation of extracellular signal-regulated kinase 1/2 and decreased phosphorylation of p38 and c-Jun N-terminal kinase 1/2. Additionally, horse oil reduced UVB-induced binding of activator protein 1 to the matrix metalloproteinase-1 promoter site. These results indicate that horse oil protects human HaCaT keratinocytes from UVB-induced oxidative stress by absorbing UVB radiation and removing reactive oxygen species, thereby protecting cells from structural damage and preventing cell death and aging. In conclusion, horse oil is a potential skin protectant against skin damage involving oxidative stress.
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Zhu, Cailing, Jingjing Zhang, Zhiqiang Wang i Hai Lin. "Excitability of high-energy ultraviolet radiation for Dy3+ in antimony phosphate glasses". Materials Science-Poland 35, nr 2 (26.07.2017): 346–54. http://dx.doi.org/10.1515/msp-2017-0025.
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Abstract Dy3+ doped antimony phosphate (ZASP) glasses are synthesized and the specificity of the luminescence behavior is demonstrated. Different from the conventional long-wave ultraviolet (UVA) exciting cases, the excitable area of Dy3+ doped ZASP glasses is extended to high-energy ultraviolet radiation including medium-wave ultraviolet (UVB) and short-wave ultraviolet (UVC) spectral regions. The quantum efficiency for 4F9/2 level of Dy3+ in low- and medium-concentration Dy2O3 doping cases reaches 95.0 % and 66.7 %, respectively, confirming the emission effectiveness from Dy3+ in ZASP glasses. The values of energy-transfer probability (P) have obvious difference while using 340 nm and 540 nm as monitoring wavelengths, so asthe energy-transfer efficiencies (η), which are related to the energy-transfer processes from discrepant Sb3+ donors to Dy3+ acceptors, were in-equivalent. The effective excitability of high-energy ultraviolet radiation illustrates that Dy3+ doped ZASP glasses are a promising candidate in developing visible light sources, display devices and tunable visible lasers.
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Kim, Juewon, Jeongin Lee i Hyunjung Choi. "Intense Pulsed Light Attenuates UV-Induced Hyperimmune Response and Pigmentation in Human Skin Cells". International Journal of Molecular Sciences 22, nr 6 (20.03.2021): 3173. http://dx.doi.org/10.3390/ijms22063173.
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The skin of an organism is affected by various environmental factors and fights against aging stress via mechanical and biochemical responses. Photoaging induced by ultraviolet B (UVB) irradiation is common and is the most vital factor in the senescence phenotype of skin, and so, suppression of UVB stress-induced damage is critical. To lessen the UVB-induced hyperimmune response and hyperpigmentation, we investigated the ameliorative effects of intense pulsed light (IPL) treatment on the photoaged phenotype of skin cells. Normal human epidermal keratinocytes and human epidermal melanocytes were exposed to 20 mJ/cm2 of UVB. After UVB irradiation, the cells were treated with green (525–530 nm) and yellow (585–592 nm) IPL at various time points prior to the harvest step. Subsequently, various signs of excessive immune response, including expression of proinflammatory and melanogenic genes and proteins, cellular oxidative stress level, and antioxidative enzyme activity, were examined. We found that IPL treatment reduced excessive cutaneous immune reactions by suppressing UVB-induced proinflammatory cytokine expression. IPL treatment prevented hyperpigmentation, and combined treatment with green and yellow IPL synergistically attenuated both processes. IPL treatment may exert protective effects against UVB injury in skin cells by attenuating inflammatory cytokine and melanogenic gene overexpression, possibly by reducing intracellular oxidative stress. IPL treatment also preserves antioxidative enzyme activity under UVB irradiation. This study suggests that IPL treatment is a useful strategy against photoaging, and provides evidence supporting clinical approaches with non-invasive light therapy.
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Liu, Jingwei, Yanjie Liang, Shao Yan, Dongxun Chen, Shihai Miao, Weili Wang i Jianqiang Bi. "Sunlight-activated long persistent luminescence in the ultraviolet-B spectral region from Bi3+-doped garnet phosphors for covert optical tagging". Journal of Materials Chemistry C 9, nr 30 (2021): 9692–701. http://dx.doi.org/10.1039/d1tc01922h.
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A series of Bi3+-doped garnet-based UVB persistent phosphors have been developed, which can be conveniently charged by either a standard 254 nm lamp or natural sunlight, producing persistent UVB light emission peaking at 313 nm.
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Hanker, J., B. Giammara i G. Strauss. "Neutrophil Myeloperoxidase Destruction by Ultraviolet Irradiation". Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 138–39. http://dx.doi.org/10.1017/s0424820100102778.
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Only a fraction of the UV radiation emitted by the sun reaches the earth; most of the UVB (290-320nm) is eliminated by stratospheric ozone. There is increasing concern, however, that man-made chemicals are damaging this ozone layer. Although the effects of UV on DNA or as a carcinogen are widely known, preleukemia and acute myeloid leukemia (AML) have only rarely been reported in psoriasis patients treated with 8-methoxypsoralen and UV (PUVA). It was therefore of interest to study the effects of UV on the myeloperoxidase (MP) activity of human neutrophils. The peroxidase activity of enriched leukocyte preparations on coverslips was shown cytochemically with a diaminobenzidine medium and cupric nitrate intensification.Control samples (Figs. 1,4,5) of human bloods that were not specifically exposed to UV radiation or light except during routine handling were compared with samples which had been exposed in one of several different ways. One preparation (Fig. 2) was from a psoriasis patient who had received whole-body UVB phototherapy repeatedly.
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Toivonen, Peter M. A., Jared Stoochnoff, Kevin Usher, Changwen Lu, Paul A. Wiersma i Chunhua Zhou. "Biochemical and Gene Expression Involved in Red Blush Color Development in ‘Ambrosia’ Apple". Journal of the American Society for Horticultural Science 144, nr 3 (maj 2019): 164–71. http://dx.doi.org/10.21273/jashs04606-18.
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The market value of the apple (Malus ×domestica Borkh.) cultivar Ambrosia is closely linked to the characteristic blush on the skin surface. For ‘Ambrosia’ orchards that produce consistently low levels of surface blush, the implementation of reflective rowcovering has improved surface coloration, but the reflected wavebands responsible for this enhanced color production have not been confirmed. This study consisted of two separate experiments: one conducted in the field to confirm reflective rowcovering efficacy and the other in a controlled environment cabinet to determine which waveband was enhancing red blush production. The red blush production in orchards with and without reflective rowcovering was then directly compared with the red blush produced on the surface of apples that were poorly colored at harvest and then exposed to visible, fluorescent, ultraviolet A (UVA), or ultraviolet B (UVB) light sources within the controlled environment chamber. Consequent analysis of the red blush color within the Commission Internationale de l’Eclairage a* and b* color space was conducted to evaluate the quality of the red blush pigment under each treatment in the field and the controlled environment chamber. The analysis revealed that the red blush that developed on apples from the reflective rowcover treatment most closely matched the red blush that developed in response to UVB exposure in the controlled environment cabinet. Further analysis of gene expression and anthocyanin contents in the ‘Ambrosia’ apples support the hypothesis that the primary driver for the characteristic red blush development, when reflective rowcovers are used, is increased exposure to UVB light.
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Oh, Seung-Taek, Dae-Hwan Park i Jae-Hyun Lim. "Designing Safe General LED Lighting that Provides the UVB Benefits of Sunlight". Applied Sciences 9, nr 5 (26.02.2019): 826. http://dx.doi.org/10.3390/app9050826.
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The ultraviolet (UV) rays emitted from sunlight greatly influence human health. Excessive exposure to UV rays can be harmful to eyes and skin; however, limited UVB exposure is essential for the synthesis of vitamin D. Nowadays, owing to insufficient exposure to natural light, there is increasing concerns about low vitamin D amongst individuals. To address this issue, many lighting devices that provide UVB doses have been released; however, such devices are only used for treatments or for special purposes. This study proposes a general indoor lighting system with a UVB LED light source to provide safe UVB doses to users who spend large amounts of time indoors. The optical characteristics of two UVB LEDs with output of 20 and 100 mW were analyzed based on their distances and applied currents. The light source combination of UVB LEDS that meets the UV hazard standard of IEC-62471 was derived; this is a photobiological safety evaluation standard of LED lighting devices. We then produced a lighting module in which the UVB LED light source was applied to general LED lighting and measured and analyzed the spectral irradiance of the proposed lighting according to the measurement standard for the general lighting of IEC 62471. The actinic UV hazard (AUV) and near-UV hazard (NUV) were calculated to be 0.001 and 10 W/m2, respectively. Thus, the provision of UVB dose did not pose any risks. In addition, the total EUV (Erythemal weighted UV) dose when the proposed lighting was implemented for 16 h was 187.66 J/m2, confirming that this dose did not cause erythema for the general skin types (Skin Types 1–6). Further, the design plan of general indoor lighting with a UVB LED light source is presented.
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Gloor, M., i A. Scherotzke. "Age dependence of ultraviolet light-induced erythema following narrow-band UVB exposure". Photodermatology, Photoimmunology & Photomedicine 18, nr 3 (czerwiec 2002): 121–26. http://dx.doi.org/10.1034/j.1600-0781.2002.00756.x.
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Maini, Sabia, Brian M. Fahlman i Ed S. Krol. "Flavonols Protect Against UV Radiation-Induced Thymine Dimer Formation in an Artificial Skin Mimic". Journal of Pharmacy & Pharmaceutical Sciences 18, nr 4 (25.10.2015): 600. http://dx.doi.org/10.18433/j34w39.
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Purpose: Exposure of skin to ultraviolet light has been shown to have a number of deleterious effects including photoaging, photoimmunosuppression and photoinduced DNA damage which can lead to the development of skin cancer. In this paper we present a study on the ability of three flavonols to protect EpiDerm™, an artificial skin mimic, against UV-induced damage. Methods: EpiDerm™ samples were treated with flavonol in acetone and exposed to UVA (100 kJ/m2 at 365 nm) and UVB (9000 J/m2 at 310 nm) radiation. Secretion of matrix metalloproteinase-1 (MMP-1) and tumor necrosis factor-α (TNF-a) were determined by ELISA, cyclobutane pyrimidine dimers were quantified using LC-APCI-MS. Results: EpiDerm ™ treated topically with quercetin significantly decreased MMP-1 secretion induced by UVA (100 µM) or UVB (200 µM) and TNF-a secretion was significantly reduced at 100 µM quercetin for both UVA and UVB radiation. In addition, topically applied quercetin was found to be photostable over the duration of the experiment. EpiDerm™ samples were treated topically with quercetin, kaempferol or galangin (52 µM) immediately prior to UVA or UVB exposure, and the cyclobutane thymine dimers (T-T (CPD)) were quantified using an HPLC-APCI MS/MS method. All three flavonols significantly decreased T-T (CPD) formation in UVB irradiated EpiDerm™, however no effect could be observed for the UVA irradiation experiments as thymine dimer formation was below the limit of quantitation. Conclusions: Our results suggest that flavonols can provide protection against UV radiation-induced skin damage through both antioxidant activity and direct photo-absorption. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.
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Keshari, Sunita, Arun Balasubramaniam, Binderiya Myagmardoloonjin, Deron Raymond Herr, Indira Putri Negari i Chun-Ming Huang. "Butyric Acid from Probiotic Staphylococcus epidermidis in the Skin Microbiome Down-Regulates the Ultraviolet-Induced Pro-Inflammatory IL-6 Cytokine via Short-Chain Fatty Acid Receptor". International Journal of Molecular Sciences 20, nr 18 (11.09.2019): 4477. http://dx.doi.org/10.3390/ijms20184477.
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The glycerol fermentation of probiotic Staphylococcus epidermidis (S. epidermidis) in the skin microbiome produced butyric acid in vitro at concentrations in the millimolar range. The exposure of dorsal skin of mice to ultraviolet B (UVB) light provoked a significant increased production of pro-inflammatory interleukin (IL)-6 cytokine. Topical application of butyric acid alone or S. epidermidis with glycerol remarkably ameliorated the UVB-induced IL-6 production. In vivo knockdown of short-chain fatty acid receptor 2 (FFAR2) in mouse skin considerably blocked the probiotic effect of S. epidermidis on suppression of UVB-induced IL-6 production. These results demonstrate that butyric acid in the metabolites of fermenting skin probiotic bacteria mediates FFAR2 to modulate the production of pro-inflammatory cytokines induced by UVB.
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Han, Hee-Soo, Ji-Sun Shin, Da-Bin Myung, Hye Ahn, Sun Lee, Hyoung Kim i Kyung-Tae Lee. "Hydrangea serrata (Thunb.) Ser. Extract Attenuate UVB-Induced Photoaging through MAPK/AP-1 Inactivation in Human Skin Fibroblasts and Hairless Mice". Nutrients 11, nr 3 (1.03.2019): 533. http://dx.doi.org/10.3390/nu11030533.
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Skin photoaging is mainly caused by exposure to ultraviolet (UV) light, which increases expressions of matrix metalloproteinases (MMPs) and destroys collagen fibers, consequently inducing wrinkle formation. Nutritional factors have received scientific attention for use as agents for normal skin functions. The aim of this study was to investigate the effect of hot water extracts from the leaves of Hydrangea serrata (Thunb.) Ser. (WHS) against ultraviolet B (UVB)-induced skin photoaging and to elucidate the underlying molecular mechanisms in human foreskin fibroblasts (Hs68) and HR-1 hairless mice. WHS recovered UVB-reduced cell viability and ameliorated oxidative stress by inhibiting intracellular reactive oxygen species (ROS) generation in Hs68 cells. WHS rescued UVB-induced collagen degradation by suppressing MMP expression, and reduced the mRNA levels of inflammatory cytokines. These anti-photoaging activities of WHS were associated with inhibition of the activator protein 1 (AP-1), signal transduction and activation of transcription 1 (STAT1), and mitogen-activated protein kinase (MAPK) signaling pathways. Oral administration of WHS effectively alleviated dorsal skin from wrinkle formation, epidermal thickening, collagen degradation, and skin dehydration in HR-1 hairless mice exposed to UVB. Notably, WHS suppressed UVB activation of the AP-1 and MAPK signaling pathways in dorsal mouse skin tissues. Taken together, our data indicate that WHS prevents UVB-induced skin damage due to collagen degradation and MMP activation via inactivation of MAPK/AP-1 signaling pathway.
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Batchelor, Jonathan M., Adam Millington, Kim S. Thomas, Perways Akram, Jaskiran Azad, Anthony Bewley, Joanne R. Chalmers i in. "Home-based narrowband UVB, topical corticosteroid or combination for children and adults with vitiligo: HI-Light Vitiligo three-arm RCT". Health Technology Assessment 24, nr 64 (listopad 2020): 1–128. http://dx.doi.org/10.3310/hta24640.
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Background Systematic reviews suggest that narrowband ultraviolet B light combined with treatments such as topical corticosteroids may be more effective than monotherapy for vitiligo. Objective To explore the clinical effectiveness and cost-effectiveness of topical corticosteroid monotherapy compared with (1) hand-held narrowband ultraviolet B light monotherapy and (2) hand-held narrowband ultraviolet B light/topical corticosteroid combination treatment for localised vitiligo. Design Pragmatic, three-arm, randomised controlled trial with 9 months of treatment and a 12-month follow-up. Setting Sixteen UK hospitals – participants were recruited from primary and secondary care and the community. Participants Adults and children (aged ≥ 5 years) with active non-segmental vitiligo affecting ≤ 10% of their body area. Interventions Topical corticosteroids [mometasone furoate 0.1% (Elocon®, Merck Sharp & Dohme Corp., Merck & Co., Inc., Whitehouse Station, NJ, USA) plus dummy narrowband ultraviolet B light]; narrowband ultraviolet B light (narrowband ultraviolet B light plus placebo topical corticosteroids); or combination (topical corticosteroids plus narrowband ultraviolet B light). Topical corticosteroids were applied once daily on alternate weeks and narrowband ultraviolet B light was administered every other day in escalating doses, with a dose adjustment for erythema. All treatments were home based. Main outcome measures The primary outcome was self-assessed treatment success for a chosen target patch after 9 months of treatment (‘a lot less noticeable’ or ‘no longer noticeable’ on the Vitiligo Noticeability Scale). Secondary outcomes included blinded assessment of primary outcome and percentage repigmentation, onset and maintenance of treatment response, quality of life, side effects, treatment burden and cost-effectiveness (cost per additional successful treatment). Results In total, 517 participants were randomised (adults, n = 398; and children, n = 119; 52% male; 57% paler skin types I–III, 43% darker skin types IV–VI). At the end of 9 months of treatment, 370 (72%) participants provided primary outcome data. The median percentage of narrowband ultraviolet B light treatment-days (actual/allocated) was 81% for topical corticosteroids, 77% for narrowband ultraviolet B light and 74% for combination groups; and for ointment was 79% for topical corticosteroids, 83% for narrowband ultraviolet B light and 77% for combination. Target patch location was head and neck (31%), hands and feet (32%), and rest of the body (37%). Target patch treatment ‘success’ was 20 out of 119 (17%) for topical corticosteroids, 27 out of 123 (22%) for narrowband ultraviolet B light and 34 out of 128 (27%) for combination. Combination treatment was superior to topical corticosteroids (adjusted risk difference 10.9%, 95% confidence interval 1.0% to 20.9%; p = 0.032; number needed to treat = 10). Narrowband ultraviolet B light was not superior to topical corticosteroids (adjusted risk difference 5.2%, 95% confidence interval –4.4% to 14.9%; p = 0.290; number needed to treat = 19). The secondary outcomes supported the primary analysis. Quality of life did not differ between the groups. Participants who adhered to the interventions for > 75% of the expected treatment protocol were more likely to achieve treatment success. Over 40% of participants had lost treatment response after 1 year with no treatment. Grade 3 or 4 erythema was experienced by 62 participants (12%) (three of whom were using the dummy) and transient skin thinning by 13 participants (2.5%) (two of whom were using the placebo). We observed no serious adverse treatment effects. For combination treatment compared with topical corticosteroids, the unadjusted incremental cost-effectiveness ratio was £2328.56 (adjusted £1932) per additional successful treatment (from an NHS perspective). Limitations Relatively high loss to follow-up limits the interpretation of the trial findings, especially during the post-intervention follow-up phase. Conclusion Hand-held narrowband ultraviolet B light plus topical corticosteroid combination treatment is superior to topical corticosteroids alone for treatment of localised vitiligo. Combination treatment was relatively safe and well tolerated, but was effective in around one-quarter of participants only. Whether or not combination treatment is cost-effective depends on how much decision-makers are willing to pay for the benefits observed. Future work Development and testing of new vitiligo treatments with a greater treatment response and longer-lasting effects are needed. Trial registration Current Controlled Trials ISRCTN17160087. Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 64. See the NIHR Journals Library website for further project information.
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Guo, Linhao, Zelin Hu, Rongqiao Wan, Linyun Long, Tao Li, Jianchang Yan, Yun Lin, Lei Zhang, Wenhui Zhu i Liancheng Wang. "Design of aluminum nitride metalens for broadband ultraviolet incidence routing". Nanophotonics 8, nr 1 (4.12.2018): 171–80. http://dx.doi.org/10.1515/nanoph-2018-0151.
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AbstractUltraviolet (UV) photonics-based device and equipment have various applications in sterilization, military covert communication, medical treatment, nanofabrication, gem identification and so on. The traditional constituent UV components are bulky, inefficient, expensive and easily aging under UV radiation. An all-dielectric metasurface offers a promising way to control the amplitude, polarization and phase of light by engineering the size, shape and distribution of its constituent elements. However, UV components based on all-dielectric metasurfaces are difficult to be realized, due to significant absorption loss for most dielectric materials at the UV region. Here we demonstrate the design of a UV metalens, composed of high-aspect-ratio aluminum nitride nanorods. The in-plane on-axis, off-axis and out-of-plane focusing characteristics have been investigated at representative UVA (375 nm), UVB (308 nm) and UVC (244 nm) wavelengths, respectively. Furthermore, we design UV router for mono-wavelength and multiple wavelengths, that is, guiding UV light to designated different spatial positions. Our work is promising for the development of UV photonic devices and would facilitate the integration and miniaturization of the UV nanophotonics.
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Sydney, Thomas, Jo-Ann Marshall-Thompson, Rahul Kapoore, Seetharaman Vaidyanathan, Jagroop Pandhal i J. Fairclough. "The Effect of High-Intensity Ultraviolet Light to Elicit Microalgal Cell Lysis and Enhance Lipid Extraction". Metabolites 8, nr 4 (15.10.2018): 65. http://dx.doi.org/10.3390/metabo8040065.
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Currently, the energy required to produce biofuel from algae is 1.38 times the energy available from the fuel. Current methods do not deliver scalable, commercially viable cell wall disruption, which creates a bottleneck on downstream processing. This is primarily due to the methods depositing energy within the water as opposed to within the algae. This study investigates ultraviolet B (UVB) as a disruption method for the green algae Chlamydomonas reinhardtii, Dunaliella salina and Micractinium inermum to enhance solvent lipid extraction. After 232 seconds of UVB exposure at 1.5 W/cm2, cultures of C. reinhardtii (culture density 0.7 mg/mL) showed 90% disruption, measured using cell counting, correlating to an energy consumption of 5.6 MJ/L algae. Small-scale laboratory tests on C. reinhardtii showed bead beating achieving 45.3 mg/L fatty acid methyl esters (FAME) and UV irradiation achieving 79.9 mg/L (lipids solvent extracted and converted to FAME for measurement). The alga M. inermum required a larger dosage of UVB due to its thicker cell wall, achieving a FAME yield of 226 mg/L, compared with 208 mg/L for bead beating. This indicates that UV disruption had a higher efficiency when used for solvent lipid extraction. This study serves as a proof of concept for UV irradiation as a method for algal cell disruption.
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Hiriart, Véronique P., Bruce M. Greenberg, Stephanie J. Guildford i Ralph EH Smith. "Effects of ultraviolet radiation on rates and size distribution of primary production by Lake Erie phytoplankton". Canadian Journal of Fisheries and Aquatic Sciences 59, nr 2 (1.02.2002): 317–28. http://dx.doi.org/10.1139/f01-212.
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The impact of natural solar ultraviolet radiation (UVR), particularly UVB (297320 nm), on phytoplankton primary production in Lake Erie was investigated during the spring and summer of 1997. Radiocarbon incorporation and size-selective filtration was used to trace total production and its distribution among particulate and dissolved pools. On average, 1-h exposures produced half the UVB-dependent inhibition of total production realized in 8-h exposures, indicating rapid kinetics of photoinhibition. Cumulative UVB-dependent photoinhibition averaged 36% in 8-h simulated surface exposures. The efficiency of photoinhibition was greater for N-deficient than N-replete communities, but was not related to phytoplankton light history, P limitation, or the dominant genera. The proportion of recently fixed carbon occurring in the dissolved pool after 8-h exposures was significantly greater in higher-UVB treatments, whereas the share in picoplankton (<2 µm) was significantly lower. Significant UVB-dependent inhibition of total production was limited on average to relatively severe exposures, but the rapid kinetics of inhibition and the apparent effects on the allocation of carbon suggest it may be important to the lake's food web. Differences in optical properties and thermal stratification patterns suggested that the relatively turbid west basin was potentially more susceptible to UVR photoinhibition than the more transparent east or central basins.
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Wu, Shulian, Zheng Huang, Yunxia Wang i Hui Li. "Characterizing UVB-induced skin tumor process using optical coherence tomography". Journal of Innovative Optical Health Sciences 09, nr 05 (18.07.2016): 1650014. http://dx.doi.org/10.1142/s1793545816500140.
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The incidence of nonmelanoma skin cancer is rising worldwide. The major carcinogenic factor for most skin cancers is solar ultraviolet light, in particular, the chronic exposure to UVB (280–320[Formula: see text]nm). In this study, the optical characteristics of skin canceration process induced by UVB were analyzed. Optical coherence tomography (OCT) was used for monitoring the morphologic changes and compared with histological analysis. Meanwhile, the optical property, such as the attenuation coefficient ([Formula: see text]t) was systematically extracted and analyzed. In addition, characteristic textures, including energy, entropy and correlation were revealed from OCT images. Results suggest that OCT is a useful tool for monitoring the process of UVB-induced skin cancer and changes of optical property during this process.
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Kobayashi, Mao, Shokoku Shu, Kana Marunaka, Toshiyuki Matsunaga i Akira Ikari. "Weak Ultraviolet B Enhances the Mislocalization of Claudin-1 Mediated by Nitric Oxide and Peroxynitrite Production in Human Keratinocyte-Derived HaCaT Cells". International Journal of Molecular Sciences 21, nr 19 (27.09.2020): 7138. http://dx.doi.org/10.3390/ijms21197138.
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A tight junction (TJ) makes a physical barrier in the epidermal cells of skin. Ultraviolet (UV) light may disrupt the TJ barrier, but the mechanism has not been well clarified. Weak UVB (5 mJ/cm2) caused mislocalization of claudin-1 (CLDN1), a component of the TJ strand, and disruption of TJ barrier in human keratinocyte-derived HaCaT cells. The UVB-induced mislocalization of CLDN1 was inhibited by monodansylcadaverine (MDC), a clathrin-dependent endocytosis inhibitor, suggesting that UVB enhances the internalization of CLDN1. Transepidermal electrical resistance and paracellular flux of lucifer yellow, a fluorescent hydrophilic marker, were rescued by MDC. UVB changed neither the total nor phosphorylation levels of CLDN1, but it increased both mono-ubiquitination and tyrosine nitration levels of CLDN1. Fluorescence measurements revealed that UVB increased intracellular free Ca2+, nitric oxide (NO), and peroxynitrite contents, which were inhibited by Opsin2 (OPN2) siRNA, suggesting that OPN2 functions as a UVB sensor. The effects of UVB were inhibited by an antagonist of transient receptor potential type vanilloid 1 (TRPV1) and Ca2+ chelator. Both NO donor and peroxynitrite donor induced the mislocalization of CLDN1 and disruption of TJ barrier, which were rescued by a NO synthase (NOS) inhibitor and a peroxynitrite scavenger. Weak UVB irradiation induced the disruption of TJ barrier mediated by mislocalization of CLDN1 in HaCaT cells. The OPN2/TRPV1/NOS signaling pathway may be a novel target for preventing destruction of the TJ barrier by UVB irradiation.
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Sugianto, Monita, Achadiyani Achadiyani i Gaga Irawan Nugraha. "Antioxidant Effects of Red Fruit Oil on MMP-1 Gene Expression and Malondialdehyde Levels on Skin Exposed to UVB Rays". Molecular and Cellular Biomedical Sciences 3, nr 2 (1.09.2019): 100. http://dx.doi.org/10.21705/mcbs.v3i2.68.
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Background: Chronic exposure ultraviolet (UV)-B radiation causes reactive oxygen species (ROS) formation. Furthermore, ROS will induce the formation of malondialdehyde and increase matrix metalloproteinase (MMP)-1 expression. One strategy against the free radicals effects is by consuming antioxidants. This study aims to analyze the antioxidants effect of red fruit oil (RFO) on MMP-1 expression and malondialdehyde levels due to exposure to UVB rays.Materials and Methods: Thirty male Wistar rats were divided into 5 groups. The P0 group was not given treatment, the P1 group was only exposed to UVB light, the P2 group was exposed to UVB light and given 0.5 mL/200 g body weight (BW) of RFO, the P3 group was exposed to UVB light and given 1 mL/200 g BW of RFO, and group P4 exposed to UVB rays and given 2 mL/200 g BW of RFO. Experimental animals would be examined for MMP-1 expression and malondialdehyde level. RFO would be identified with β-carotene and tocopherol content.Results: Beta-carotene and tocopherol were detected in RFO. RFO reduced significantly MMP-1 expression (p<0.05) in P2 group (0.73±1.27), P3 group (0.63±0.95), P4 group (9.56±20.97) compared group P1 (48.07±65.58). However, RFO did not reduce malondialdehyde levels (p>0.05).Conclusion: Our research demonstrates RFO containing tocopherol and β-carotene can reduce the MMP-1 expression, but does not affect malondialdehyde levels due to exposure to UVB rays. An effective dose that can reduce malondialdehyde levels and MMP-1 expression is 1 mL/200 g BW.Keywords: red fruit oil, antioxidant, skin, MMP-1 expression, malondialdehyde, UVB rays, photoaging
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Bosman, E. S., A. Y. Albert, J. P. Dutz i B. Vallance. "A12 SKIN EXPOSURE TO NARROW BAND UVB LIGHT MODULATES THE HUMAN INTESTINAL MICROBIOME". Journal of the Canadian Association of Gastroenterology 3, Supplement_1 (luty 2020): 15–16. http://dx.doi.org/10.1093/jcag/gwz047.011.
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Abstract Background The recent worldwide rise in idiopathic immune and inflammatory diseases such as multiple sclerosis and inflammatory bowel diseases has been linked to Western society-based changes in lifestyle and environment. These include decreased exposure to sunlight/UVB light and subsequent impairment in the production of vitamin D, as well as dysbiotic changes in the makeup of the gut microbiome. Despite their association, it is unclear if there are any direct links between UVB light and the gut microbiome. Aims In this study we investigated whether exposing the skin to Narrow Band Ultraviolet B (NB-UVB) light to increase serum vitamin D levels would also modulate the makeup of the human intestinal microbiota. Methods The effects of NB-UVB light were studied in a clinical pilot study using a healthy human female cohort (n=21). Participants were divided into those that took vitamin D supplements throughout the winter prior to the start of the study (VDS+) and those who did not (VDS-). Results After three full-body NB-UVB light exposures within the same week, the serum 25(OH)D levels of participants increased on average 7.3 nmol/L. The serum response was negatively correlated to the starting 25-hydroxy vitamin D (25(OH)D) serum concentration. Fecal microbiota composition analysis using 16S rRNA sequencing showed that exposure to NB-UVB significantly increased alpha and beta diversity in the VDS- group whereas there were no changes in the VDS+ group. Bacteria from several families were enriched in the VDS- group after the UVB exposures according to a Linear Discriminant Analysis (LDA) prediction, including Lachnospiracheae, Rikenellaceae, Desulfobacteraceae, Clostridiales vadinBB60 group, Clostridia Family XIII, Coriobacteriaceae, Marinifilaceae, and Ruminococcus. The serum 25(OH)D concentrations showed a positive correlation with the relative abundance of the Lachnospiraceae, specifically members of the Lachnopsira and Fusicatenibacter genera. Conclusions This is the first study to show that humans with low 25(OH)D serum levels display overt changes in their intestinal microbiome in response to NB-UVB skin exposure and increases in 25(OH)D levels, suggesting the existence of a novel skin-gut axis that could be used to promote intestinal homeostasis and health. Funding Agencies NRCBC Childrens Hospital Research Institute