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Sample records for vitro uva irradiation

  1. In vivo UVA irradiation of mouse is more efficient in promoting pulmonary melanoma metastasis than in vitro

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    Ylianttila Lasse

    2011-06-01

    Full Text Available Abstract Background We have previously shown in vitro that UVA increases the adhesiveness of mouse B16-F1 melanoma cells to endothelium. We have also shown in vivo that UVA exposure of C57BL/6 mice, i.v. injected with B16-F1 cells, increases formation of pulmonary colonies of melanoma. The aim of the present animal study was to confirm the previously observed in vivo UVA effect and to determine whether in vitro UVA-exposure of melanoma cells, prior the i.v. injection, will have an enhancing effect on the pulmonary colonization capacity of melanoma cells. As a second aim, UVA-derived immunosuppression was determined. Methods Mice were i.v. injected with B16-F1 cells into the tail vein and then immediately exposed to UVA. Alternatively, to study the effect of UVA-induced adhesiveness on the colonization capacity of B16-F1 melanoma, cells were in vitro exposed prior to i.v. injection. Fourteen days after injection, lungs were collected and the number of pulmonary nodules was determined under dissecting microscope. The UVA-derived immunosuppression was measured by standard contact hypersensitivity assay. Results and Discussion Obtained results have confirmed that mice, i.v. injected with B16-F1 cells and thereafter exposed to UVA, developed 4-times more of melanoma colonies in lungs as compared with the UVA non-exposed group (p in vitro exposure of melanoma cells prior to their injection into mice, led only to induction of 1.5-times more of pulmonary tumor nodules, being however a statistically non-significant change. The obtained results postulate that the UVA-induced changes in the adhesive properties of melanoma cells do not alone account for the 4-fold increase in the pulmonary tumor formation. Instead, it suggests that some systemic effect in a mouse might be responsible for the increased metastasis formation. Indeed, UVA was found to induce moderate systemic immunosuppression, which effect might contribute to the UVA-induced melanoma

  2. Establishment of Photo-aging In Vitro by Repetitive UVA Irradiation: Induction of Characteristic Markers of Senescence and its Prevention by PAPLAL with Potent Catalase Activity.

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    Yoshimoto, Satoshi; Yoshida, Moemi; Ando, Hideya; Ichihashi, Masamitsu

    2017-12-18

    To understand a role of UVA radiation in photo-aging of the skin, we established a model of photo-aging cells using cultured human dermal fibroblasts. Repeated low dose UVA radiation for 10 consecutive days induced senescence in fibroblasts, characterized with 1) increased level of senescence-associated β-galactosidase, 2) flattened large cell shape, 3) accumulation of reactive oxygen species, 4) yellowish coloration and 5) expression of p16. These were also observed in chronologically aged fibroblasts (doubling times >20), whereas none of these were detected in young cells (doubling times senescence. In addition, H 2 O 2 was produced in the culture medium by a single low dose of UVA irradiation. Further, PAPLAL, a nanoparticle of platinum and palladium having potent catalase-like activity, significantly delayed the onset of H 2 O 2 -induced cell senescence. The present study strongly indicates that repetitive short term UVA irradiation induces aging of cells possibly via H 2 O 2 and may be suppressed by potent anti-H 2 O 2 agents. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  3. Lipid nanoparticles based on butyl-methoxydibenzoylmethane: in vitro UVA blocking effect

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    Niculae, G.; Lacatusu, I.; Badea, N.; Meghea, A.

    2012-08-01

    The aim of the present study was to obtain efficient lipid nanoparticles loaded with butyl-methoxydibenzoylmethane (BMDBM) in order to develop cosmetic formulations with enhanced UVA blocking effect. For this purpose, two adequate liquid lipids (medium chain triglycerides and squalene) have been used in combination with two solid lipids (cetyl palmitate and glyceryl stearate) in order to create appropriate nanostructured carriers with a disordered lipid network able to accommodate up to 1.5% BMDBM. The lipid nanoparticles (LNs) were characterized in terms of particle size, zeta potential, entrapment efficiency, loading capacity and in vitro UVA blocking effect. The efficiency of lipid nanoparticles in developing some cosmetic formulations has been evaluated by determining the in vitro erythemal UVA protection factor. In order to quantify the photoprotective effect, some selected cream formulations based on BMDBM-LNs and a conventional emulsion were exposed to photochemical UV irradiation at a low energy to simulate the solar energy during the midday. The results obtained demonstrated the high ability of cream formulations based on BMDBM-LNs to absorb more than 96% of UVA radiation. Moreover, the developed cosmetic formulations manifest an enhanced UVA blocking effect, the erythemal UVA protection factor being four times higher than those specific to conventional emulsions.

  4. Platelet-Rich Fibrin Lysate Can Ameliorate Dysfunction of Chronically UVA-Irradiated Human Dermal Fibroblasts.

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    Wirohadidjojo, Yohanes Widodo; Budiyanto, Arief; Soebono, Hardyanto

    2016-09-01

    To determine whether platelet-rich fibrin lysate (PRF-L) could restore the function of chronically ultraviolet-A (UVA)-irradiated human dermal fibroblasts (HDFs), we isolated and sub-cultured HDFs from six different human foreskins. HDFs were divided into two groups: those that received chronic UVA irradiation (total dosages of 10 J cm⁻²) and those that were not irradiated. We compared the proliferation rates, collagen deposition, and migration rates between the groups and between chronically UVA-irradiated HDFs in control and PRF-L-treated media. Our experiment showed that chronic UVA irradiation significantly decreased (p<0.05) the proliferation rates, migration rates, and collagen deposition of HDFs, compared to controls. Compared to control media, chronically UVA-irradiated HDFs in 50% PRF-L had significantly increased proliferation rates, migration rates, and collagen deposition (p<0.05), and the migration rates and collagen deposition of chronically UVA-irradiated HDFs in 50% PRF-L were equal to those of normal fibroblasts. Based on this experiment, we concluded that PRF-L is a good candidate material for treating UVA-induced photoaging of skin, although the best method for its clinical application remains to be determined.

  5. Epidermal changes in human skin following irradiation with either UVB or UVA

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    Pearse, A.D.; Gaskell, S.A.; Marks, R.

    1987-01-01

    We have demonstrated previously that following UVB irradiation to normal volunteers there is an increase in epidermal and stratum corneum thickness and an increase in the thymidine autoradiographic labeling index. These changes are coupled with alterations in epidermal glucose-6-phosphate dehydrogenase and succinic dehydrogenase activities, despite the absence of erythema clinically. The use of a sunscreen did not completely prevent these changes. In this study, we have examined the effects of repeated irradiation of human skin with either UVB or UVA alone in order to compare the changes produced in the epidermis and to ascertain whether UVA irradiation could cause these. Irradiation with either UVB or UVA alone was found to increase the mean epidermal thickness, the mean stratum corneum thickness, and mean keratinocyte height significantly. Glucose-6-phosphate dehydrogenase activity was significantly increased throughout the epidermis, and succinic dehydrogenase activity was significantly decreased. The autoradiographic labeling index was significantly increased following UVB irradiation but not following UVA irradiation. These results demonstrate that UVA alone can have a direct effect on epidermal morphology and metabolism, suggesting that protection of skin from UV radiation should include adequate protection from UVA.

  6. In vitro testing to assess the UVA protection performance of sun care products.

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    Gers-Barlag, H; Klette, E; Bimczok, R; Springob, C; Finkel, P; Rudolph, T; Gonzenbach, H U; Schneider, P H; Kockott, D; Heinrich, U; Tronnier, H; Bernklau, R; Johncock, W; Langner, R; Driller, H J; Westenfelder, H

    2001-02-01

    The UVA protection delivered by sunscreens is an issue of increasing importance due to the increasing knowledge about UVA-induced skin damage. In Europe there is no officially accepted method available to determine the degree of UVA protection. Therefore, the objective of the present study was to design a protocol combining the merits of an in vitro model, which are simple and reproducible, with aspects known to be relevant from in vivo studies. The principle is: an UV-transparent support to which the test product is applied, a (pre)irradiation and a transmission measurement. Transpore(R) tape (standard support for SPF determinations) was found to be incompatible with many preparations on prolonged contact times. Roughened quartz was adopted as a suitable alternative. Transmission measurements on this support are not reliable with a layer of 2 mg cm(-2) (standard for SPF) due to detection limitations of spectrophotometers, hence a reduced layer of 0.75 mg cm(-2) was adopted. Overall, it is very difficult to apply products in a reproducible thin layer on appropriate substrates. As a consequence, absolute parameters derived from the transmission profile show relatively large dispersion, whereas relative parameters, such as critical wavelength lambda(c)[1] or UVA/UVB ratio are much less sensitive to unavoidable variations in layer thickness. An increase in deviations was observed when the samples were irradiated before measurement. It is crucial to control the output carefully (spectral distribution and even more importantly, irradiance and dose delivered) of the light source. By doing so and also taking into account the previous learning steps, a protocol was drafted and tested in a ringtest (four samples in six laboratories). The results are encouraging and show that if relative parameters (e.g. lambda(c), UVA/UVB ratio) are considered, the intra- as well as interlaboratory reproducibility is clearly better than can be obtained in vivo. In general, we describe a

  7. In vitro assessments of UVA protection by popular sunscreens available in the United States.

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    Wang, Steven Q; Stanfield, Joseph W; Osterwalder, Uli

    2008-12-01

    The importance of adequate ultraviolet A (UVA) protection has become apparent with improved understanding of the mechanism of UVA-induced damage to tissues. Currently in the United States, there is no regulation on testing and labeling of sunscreens for UVA protection. In August 2007, the Food and Drug Administration (FDA) addressed this issue in a proposed rule. We sought to assess in vitro the degree of UVA protection provided by 13 popular sunscreen products that are commercially available in the United States. Thirteen sunscreen products were purchased. UVA protection of each product was measured and assessed with 3 in vitro UVA labeling indices: (1) the FDA Proposed Amendment of Final Monograph, August 27, 2007; (2) European Commission Recommendation--the Colipa and critical wavelength methods; (3) and United Kingdom's Boots star rating system. Based on the new FDA-proposed guidelines, 8 products achieved the medium protection category, and 5 products achieved high protection. The latter 5 products also fulfilled the UVA protection based on the Colipa guideline desired by the European Commission Recommendation. Nine products achieved the desired critical wavelength value of 370 or higher. Based on the United Kingdom's Boots star rating system, 6 products achieved a rating of 3 stars, and the remaining 7 products achieved no star rating. The study only evaluated a small number of sunscreen products, and only in vitro methods were used to assess the degree of UVA protection. The majority of the tested sunscreens in this study offered a medium degree of UVA protection. Compared with the sunscreens in the past, this study shows that UVA protection of sunscreens has improved. Sunscreens with avobenzone and octocrylene provided a higher degree of UVA protection. Globally, there is no uniform standard on testing and labeling sunscreens for UVA protection. In the United States, the FDA has just started to create a much-needed standard. This effort is necessary to

  8. Effect of supplemental UV-A irradiation in solid-state lighting on the growth and phytochemical content of microgreens

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    Brazaitytė, A.; Viršilė, A.; Jankauskienė, J.; Sakalauskienė, S.; Samuolienė, G.; Sirtautas, R.; Novičkovas, A.; Dabašinskas, L.; Miliauskienė, J.; Vaštakaitė, V.; Bagdonavičienė, A.; Duchovskis, P.

    2015-01-01

    In this study, we sought to find and employ positive effects of UV-A irradiation on cultivation and quality of microgreens. Therefore, the goal of our study was to investigate the influence of 366, 390, and 402 nm UV-A LED wavelengths, supplemental for the basal solid-state lighting system at two UV-A irradiation levels on the growth and phytochemical contents of different microgreen plants. Depending on the species, supplemental UV-A irradiation can improve antioxidant properties of microgreens. In many cases, a significant increase in the investigated phytochemicals was found under 366 and 390 nm UV-A wavelengths at the photon flux density (12.4 μmol m-2 s-1). The most pronounced effect of supplemental UV-A irradiation was detected in pak choi microgreens. Almost all supplemental UV-A irradiation treatments resulted in increased leaf area and fresh weight, in higher 2,2-diphenyl-1-picrylhydrazyl free-radical scavenging activity, total phenols, anthocyanins, ascorbic acid, and α-tocopherol.

  9. UVA and UVB irradiation differentially regulate microRNA expression in human primary keratinocytes.

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    Anne Kraemer

    Full Text Available MicroRNA (miRNA-mediated regulation of the cellular transcriptome is an important epigenetic mechanism for fine-tuning regulatory pathways. These include processes related to skin cancer development, progression and metastasis. However, little is known about the role of microRNA as an intermediary in the carcinogenic processes following exposure to UV-radiation. We now show that UV irradiation of human primary keratinocytes modulates the expression of several cellular miRNAs. A common set of miRNAs was influenced by exposure to both UVA and UVB. However, each wavelength band also activated a distinct subset of miRNAs. Common sets of UVA- and UVB-regulated miRNAs harbor the regulatory elements GLYCA-nTRE, GATA-1-undefined-site-13 or Hox-2.3-undefined-site-2 in their promoters. In silico analysis indicates that the differentially expressed miRNAs responding to UV have potential functions in the cellular pathways of cell growth and proliferation. Interestingly, the expression of miR-23b, which is a differentiation marker of human keratinocytes, is remarkably up-regulated after UVA irradiation. Studying the interaction between miR-23b and its putative skin-relevant targets using a Luciferase reporter assay revealed that RRAS2 (related RAS viral oncogene homolog 2, which is strongly expressed in highly aggressive malignant skin cancer, to be a direct target of miR-23b. This study demonstrates for the first time a differential miRNA response to UVA and UVB in human primary keratinocytes. This suggests that selective regulation of signaling pathways occurs in response to different UV energies. This may shed new light on miRNA-regulated carcinogenic processes involved in UV-induced skin carcinogenesis.

  10. Aerosol forcing efficiency in the UVA region from spectral solar irradiance measurements at an urban environment

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    S. Kazadzis

    2009-06-01

    Full Text Available Spectral Ultraviolet (UV measurements using a Brewer MKIII double spectroradiometer were used for the determination of the aerosol forcing efficiency (RFE under cloud free conditions at Thessaloniki, Greece for the period 1998–2006. Using measured spectral UVA irradiance in combination with synchronous aerosol optical depth (AOD measurements at 340 nm, we calculated the seasonal and the percent RFE changes with the help of radiative transfer model calculations used for cloud and aerosol free conditions reference. The calculated RFE for the 325–340 nm wavelength integral was found to be −0.71±0.30 W m−2/τs340 nm and corresponds to a mean calculated RFE% value of −15.2%±3.8% (2 σ per unit of τs340 nm, for the whole period. This indicates a mean reduction of 15.2% of the 325–340 nm irradiance for a unit of aerosol optical depth slant column increase. Lower RFE% was found during summertime, which is a possible indication of lower absorbing aerosols. Mean AOD slant at 340 nm for the city of Thessaloniki were processed in combination with RFE% and a mean monthly UVA attenuation of ~10% for the whole period was revealed. The nine years' analysis results showed a reduction in RFE%, which provides a possible indication of the changes in the optical properties over the city area. If such changes are only due to changes in the aerosol absorbing properties, the above finding suggests a 2% per decade increase in UVA due to changes in the aerosol absorption properties, in addition to the calculated increase by 4.2%, which is attributed only to AOD decrease at Thessaloniki area over the 1998–2006 period.

  11. Aerosol forcing efficiency in the UVA region from spectral solar irradiance measurements at an urban environment

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    S. Kazadzis

    2009-06-01

    Full Text Available Spectral Ultraviolet (UV measurements using a Brewer MKIII double spectroradiometer were used for the determination of the aerosol forcing efficiency (RFE under cloud free conditions at Thessaloniki, Greece for the period 1998–2006. Using measured spectral UVA irradiance in combination with synchronous aerosol optical depth (AOD measurements at 340 nm, we calculated the seasonal and the percent RFE changes with the help of radiative transfer model calculations used for cloud and aerosol free conditions reference. The calculated RFE for the 325–340 nm wavelength integral was found to be −0.71±0.30 W m−2/τs340 nm and corresponds to a mean calculated RFE% value of −15.2%±3.8% (2 σ per unit of τs340 nm, for the whole period. This indicates a mean reduction of 15.2% of the 325–340 nm irradiance for a unit of aerosol optical depth slant column increase. Lower RFE% was found during summertime, which is a possible indication of lower absorbing aerosols. Mean AOD slant at 340 nm for the city of Thessaloniki were processed in combination with RFE% and a mean monthly UVA attenuation of ~10% for the whole period was revealed. The nine years' analysis results showed a reduction in RFE%, which provides a possible indication of the changes in the optical properties over the city area. If such changes are only due to changes in the aerosol absorbing properties, the above finding suggests a 2% per decade increase in UVA due to changes in the aerosol absorption properties, in addition to the calculated increase by 4.2%, which is attributed only to AOD decrease at Thessaloniki area over the 1998–2006 period.

  12. 3-Amino-1,2,4-triazole Limits the Oxidative Damage in UVA-Irradiated Dysplastic Keratinocytes

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    Marina Tamara Nechifor

    2017-01-01

    Full Text Available Reactive oxygen species (ROS generated by UVA irradiation affect the keratinocyte cell membrane, DNA, and proteins and may cause serious injury to the skin. Treating human dysplastic keratinocytes (DOK with 3-amino-1,2,4-triazole (AMT, a common catalase inhibitor, induced a compensatory mechanism for the hydrogen peroxide detoxification, which included a rise in glutathione peroxidase and glutathione reductase activities. Here, we examined a possible role of AMT in protecting a human DOK cell line against UVA-induced damage. In DOK cells exposed to UVA irradiation, we observed a substantial decrease in antioxidant enzymatic activities, such as catalase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase and an increase in lipid peroxidation and protein oxidation levels. Treating DOK cells with AMT prior to UVA exposure enhanced the activities of glutathione peroxidase, glutathione reductase, and glutathione-S-transferase, relative to nontreated cells. The enhanced antioxidant activities were correlated with decreased protein oxidation levels. Based on these results, we suggest that AMT may protect dysplastic keratinocytes against the harmful effects of UVA radiation.

  13. Protein oxidation and aggregation in UVA-irradiated Escherichia coli cells as signs of accelerated cellular senescence.

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    Bosshard, Franziska; Riedel, Kathrin; Schneider, Thomas; Geiser, Carina; Bucheli, Margarete; Egli, Thomas

    2010-11-01

    Solar disinfection (SODIS) is a simple drinking water treatment method that improves microbiological water quality where other means are unavailable. It makes use of the deleterious effect of solar irradiation on pathogenic microbes and viruses. A positive impact on health has been documented in several epidemiological studies. However, the molecular mechanisms damaging cells during this simple treatment are not yet fully understood. Here we show that protein damage is crucial in the process of inactivation by sunlight. Protein damages in UVA-irradiated Escherichia coli cells have been evaluated by an immunoblot method for carbonylated proteins and an aggregation assay based on semi-quantitative proteomics. A wide spectrum of structural and enzymatic proteins within the cell is affected by carbonylation and aggregation. Vital cellular functions like the transcription and translation apparatus, transport systems, amino acid synthesis and degradation, respiration, ATP synthesis, glycolysis, the TCA cycle, chaperone functions and catalase are targeted by UVA irradiation. The protein damage pattern caused by SODIS strongly resembles the pattern caused by reactive oxygen stress. Hence, sunlight probably accelerates cellular senescence and leads to the inactivation and finally death of UVA-irradiated cells. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.

  14. Matrix metalloproteinase-1 inhibitory activities of Morinda citrifolia seed extract and its constituents in UVA-irradiated human dermal fibroblasts.

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    Masuda, Megumi; Murata, Kazuya; Naruto, Shunsuke; Uwaya, Akemi; Isami, Fumiyuki; Matsuda, Hideaki

    2012-01-01

    The objective of this study was to examine whether a 50% ethanolic extract (MCS-ext) of the seeds of Morinda citrifolia (noni) and its constituents have matrix metalloproteinase-1 (MMP-1) inhibitory activity in UVA-irradiated normal human dermal fibroblasts (NHDFs). The MCS-ext (10 μg/mL) inhibited MMP-1 secretion from UVA-irradiated NHDFs, without cytotoxic effects, at 48 h after UV exposure. The ethyl acetate-soluble fraction of MCS-ext was the most potent inhibitor of MMP-1 secretion. Among the constituents of the fraction, a lignan, 3,3'-bisdemethylpinoresinol (1), inhibited the MMP-1 secretion at a concentration of 0.3 μM without cytotoxic effects. Furthermore, 1 (0.3 μM) reduced the level of intracellular MMP-1 expression. Other constituents, namely americanin A (2), quercetin (3) and ursolic acid (4), were inactive. To elucidate inhibition mechanisms of MMP-1 expression and secretion, the effect of 1 on mitogen-activated protein kinases (MAPKs) phosphorylation was examined. Western blot analysis revealed that 1 (0.3 μM) reduced the phosphorylations of p38 and c-Jun-N-terminal kinase (JNK). These results suggested that 1 suppresses intracellular MMP-1 expression, and consequent secretion from UVA-irradiated NHDFs, by down-regulation of MAPKs phosphorylation.

  15. A simplified procedure for semi-targeted lipidomic analysis of oxidized phosphatidylcholines induced by UVA irradiation

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    Gruber, Florian; Bicker, Wolfgang; Oskolkova, Olga V.; Tschachler, Erwin; Bochkov, Valery N.

    2012-01-01

    Oxidized phospholipids (OxPLs) are increasingly recognized as signaling mediators that are not only markers of oxidative stress but are also “makers” of pathology relevant to disease pathogenesis. Understanding the biological role of individual molecular species of OxPLs requires the knowledge of their concentration kinetics in cells and tissues. In this work, we describe a straightforward “fingerprinting” procedure for analysis of a broad spectrum of molecular species generated by oxidation of the four most abundant species of polyunsaturated phosphatidylcholines (OxPCs). The approach is based on liquid-liquid extraction followed by reversed-phase HPLC coupled to electrospray ionization MS/MS. More than 500 peaks corresponding in retention properties to polar and oxidized PCs were detected within 8 min at 99 m/z precursor values using a single diagnostic product ion in extracts from human dermal fibroblasts. Two hundred seventeen of these peaks were fluence-dependently and statistically significantly increased upon exposure of cells to UVA irradiation, suggesting that these are genuine oxidized or oxidatively fragmented species. This method of semitargeted lipidomic analysis may serve as a simple first step for characterization of specific “signatures” of OxPCs produced by different types of oxidative stress in order to select the most informative peaks for identification of their molecular structure and biological role. PMID:22414483

  16. UVA I-protection effectiveness of bioactive compound and organic UV filters: an in vitro assessment

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    André Rolim Baby

    2009-01-01

    Full Text Available This research work aimed at determining the UVA effectiveness (UVA I/UV ratio, by diffuse transmittance analysis, of sunscreens developed with a bioactive substance, the rutin, associating or not with organic UVB-UVA filters incorporated at a phosphate-base O/W emulsion. Sunscreens provided conflicting and unpredictable results concerning the anti-UVA protection, specially, at the UVA I region. Possible interactions among the organic UV filters and the polyphenolic bioactive substance may have accounted with improvement or reduction of UV protection by a complex and not yet elucidated mechanism, probably regarding wavelength delocalization to superior or inferior values, by resonant molecule stabilization or destabilization.

  17. Antimicrobial photodisinfection with Zn(II) phthalocyanine adsorbed on TiO2 upon UVA and red irradiation

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    Mantareva, Vanya; Eneva, Ivelina; Kussovski, Vesselin; Borisova, Ekaterina; Angelov, Ivan

    2015-01-01

    The light exposure on a daily basis has been well accepted as a competitive method for decontamination of wastewater. The catalytic properties of TiO2 offer a great potential to reduce the transmission of pathogens in the environment. Although the titanium dioxide shows high activity against pathogens, its general usage in water cleaning is limited due to the insufficient excitation natural light (about 3% of the solar spectrum). A hydrophobic dodecylpyridyloxy Zn(II)-phthalocyanine with four peripheral hydrocarbon chains of C12 (ZnPcDo) was immobilized on a photocatalyst TiO2 anatase (P25). The resulted greenish colored nanoparticles of phthalocyanine were characterized by the means of absorption, fluorescence and infrared spectroscopy. The laser scanning confocal fluorescence microscopy was used to visualize the phthalocyanine dye by the red fluorescence emission (650 - 740 nm). The intensive Q-band in the far red visible spectral region (~ 690 nm) suggested a monomeric state of phthalocyanine on TiO2 nanoparticles. Two pathogenic bacterial strains (methicillin-resistant Staphylococcus aureus - MRSA and Salmonella enteritidis) associated with wastewater were photoinactivated with the suspension of the particles. The effective photoinactivation was observed with 1 g.L-1 TiO2 anatase at irradiation with UVA 364 nm as with UVA 364 nm and LED 643 nm. The gram-negative Salmonella enteritidis was fully photoinactivated with ZnPcDo-TiO2 and TiO2 alone at UVA 346 nm and at irradiation with two light sources (364 nm + 643 nm). The proposed conjugate appears as an useful composite material for antibacterial disinfection.

  18. Effects of zinc oxide and titanium dioxide nanoparticles on green algae under visible, UVA, and UVB irradiations: no evidence of enhanced algal toxicity under UV pre-irradiation.

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    Lee, Woo-Mi; An, Youn-Joo

    2013-04-01

    Some metal oxide nanoparticles are photoreactive, thus raising concerns regarding phototoxicity. This study evaluated ecotoxic effects of zinc oxide nanoparticles and titanium dioxide nanoparticles to the green algae Pseudokirchneriella subcapitata under visible, UVA, and UVB irradiation conditions. The nanoparticles were prepared in algal test medium, and the test units were pre-irradiated by UV light in a photoreactor. Algal assays were also conducted with visible, UVA or UVB lights only without nanoparticles. Algal growth was found to be inhibited as the nanoparticle concentration increased, and ZnO NPs caused destabilization of the cell membranes. We also noted that the inhibitory effects on the growth of algae were not enhanced under UV pre-irradiation conditions. This phenomenon was attributed to the photocatalytic activities of ZnO NPs and TiO2 NPs in both the visible and UV regions. The toxicity of ZnO NPs was almost entirely the consequence of the dissolved free zinc ions. This study provides us with an improved understanding of toxicity of photoreactive nanoparticles as related to the effects of visible and UV lights. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Bacteria and fungi inactivation by photocatalysis under UVA irradiation: liquid and gas phase.

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    Rodrigues-Silva, Caio; Miranda, Sandra M; Lopes, Filipe V S; Silva, Mário; Dezotti, Márcia; Silva, Adrián M T; Faria, Joaquim L; Boaventura, Rui A R; Vilar, Vítor J P; Pinto, Eugénia

    2017-03-01

    In the last decade, environmental risks associated with wastewater treatment plants (WWTPs) have become a concern in the scientific community due to the absence of specific legislation governing the occupational exposure limits (OEL) for microorganisms present in indoor air. Thus, it is necessary to develop techniques to effectively inactivate microorganisms present in the air of WWTPs facilities. In the present work, ultraviolet light A radiation was used as inactivation tool. The microbial population was not visibly reduced in the bioaerosol by ultraviolet light A (UVA) photolysis. The UVA photocatalytic process for the inactivation of microorganisms (bacteria and fungi, ATCC strains and isolates from indoor air samples of a WWTP) using titanium dioxide (TiO 2 P25) and zinc oxide (ZnO) was tested in both liquid-phase and airborne conditions. In the slurry conditions at liquid phase, P25 showed a better performance in inactivation. For this reason, gas-phase assays were performed in a tubular photoreactor packed with cellulose acetate monolithic structures coated with P25. The survival rate of microorganisms under study decreased with the catalyst load and the UVA exposure time. Inactivation of fungi was slower than resistant bacteria, followed by Gram-positive bacteria and Gram-negative bacteria. Graphical abstract Inactivation of fungi and bacteria in gas phase by photocatalitic process performed in a tubular photoreactor packed with cellulose acetate monolith structures coated with TiO 2 .

  20. Exposure of vitamins to UVB and UVA radiation generates singlet oxygen.

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    Knak, Alena; Regensburger, Johannes; Maisch, Tim; Bäumler, Wolfgang

    2014-05-01

    Deleterious effects of UV radiation in tissue are usually attributed to different mechanisms. Absorption of UVB radiation in cell constituents like DNA causes photochemical reactions. Absorption of UVA radiation in endogenous photosensitizers like vitamins generates singlet oxygen via photosensitized reactions. We investigated two further mechanisms that might be involved in UV mediated cell tissue damage. Firstly, UVB radiation and vitamins also generate singlet oxygen. Secondly, UVB radiation may change the chemical structure of vitamins that may change the role of such endogenous photosensitizers in UVA mediated mechanisms. Vitamins were irradiated in solution using monochromatic UVB (308 nm) or UVA (330, 355, or 370 nm) radiation. Singlet oxygen was directly detected and quantified by its luminescence at 1270 nm. All investigated molecules generated singlet oxygen with a quantum yield ranging from 0.007 (vitamin D3) to 0.64 (nicotinamide) independent of the excitation wavelength. Moreover, pre-irradiation of vitamins with UVB changed their absorption in the UVB and UVA spectral range. Subsequently, molecules such as vitamin E and vitamin K1, which normally exhibit no singlet oxygen generation in the UVA, now produce singlet oxygen when exposed to UVA at 355 nm. This interplay of different UV sources is inevitable when applying serial or parallel irradiation with UVA and UVB in experiments in vitro. These results should be of particular importance for parallel irradiation with UVA and UVB in vivo, e.g. when exposing the skin to solar radiation.

  1. A broad-spectrum sunscreen prevents UVA radiation-induced gene expression in reconstructed skin in vitro and in human skin in vivo.

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    Marionnet, Claire; Grether-Beck, Susanne; Seité, Sophie; Marini, Alessandra; Jaenicke, Thomas; Lejeune, François; Bastien, Philippe; Rougier, André; Bernerd, Françoise; Krutmann, Jean

    2011-06-01

    The efficacy of sunscreens to protect against ultraviolet (UV) A radiation is usually assessed by measuring erythema formation and pigmentation. The biological relevance of these endpoints for UVA-induced skin damage, however, is not known. We therefore carried out two complementary studies to determine UVA protection provided by a broad-spectrum sunscreen product at a molecular level by studying UVA radiation-induced gene expression. One study was performed on human reconstructed skin in vitro with a semi-global gene expression analysis of 227 genes in fibroblasts and 244 in keratinocytes. The second one was conducted in vivo in human volunteers and focused on genes involved in oxidative stress response and photo-ageing (haeme oxygenase-1, superoxide dismutase-2, glutathione peroxidase, catalase, matrix metalloproteinase-1). In-vitro UVA radiation induced modulation of genes involved in extracellular matrix homeostasis, oxidative stress, heat shock responses, cell growth, inflammation and epidermal differentiation. Sunscreen pre-application abrogated or significantly reduced these effects, as underlined by unsupervised clustering analysis. The in vivo study confirmed that the sunscreen prevented UVA radiation-induced transcriptional expression of the five studied genes. These findings indicate the high efficacy of a broad-spectrum sunscreen in protecting human skin against UVA-induced gene responses and suggest that this approach is a biologically relevant complement to existing methods. © 2011 John Wiley & Sons A/S.

  2. An Innovative Therapeutic Protocol for Vitiligo: Experience with the Use of Fraxel Herbium Laser, Topical Latanoprost and Successive Irradiation with UVA - 1 Laser

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    Torello Lotti

    2018-01-01

    Full Text Available Despite the continuous introduction of innovative therapies for vitiligo, today none of them provide constant and excellent results in term of repigmentation. The authors report their experience in treating a localised form of vitiligo with a new protocol consisting in the use of a Fraxel Herbium laser, and in the following application of topical Latanoprost solution and, one day after, in lesional irradiation with UVA1 laser.

  3. Effect of Light Irradiation and Sex Hormones on Jurkat T Cells: 17β-Estradiol but Not Testosterone Enhances UVA-Induced Cytotoxicity in Jurkat Lymphocytes

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    Michael F. Angel

    2005-04-01

    Full Text Available In Eastern cultures, such as India, it is traditionally recommended that women but not men cover their heads while working in the scorching sun. The purpose of this pilot study was to determine whether there was any scientific basis for this cultural tradition. We examined the differential cytotoxic effects of ultraviolet A light (UVA on an established T cell line treated with female and male sex hormones. CD4+ Jurkat T cells were plated in 96 well plates at 2 x 106 cells/ml and treated with 17β-estradiol (EST or testosterone (TE. These cells were irradiated by UVA light with an irradiance of 170 J/cm2 for 15min at a distance of 6 cm from the surface of the 96-well plate. Controls included cells not treated with hormones or UVA. The effects of EST and TE were investigated between 1 and 20 ng/mL. Cytotoxicity by fluorescein-diacetate staining and COMET assay generating single strand DNA cleavage, tail length and tail moment measurements were examined. The effect of estrogen (5ng/mL on apoptosis and its mediators was further studied using DNA laddering and western blotting for bcl-2 and p53. We found that EST alone, without UVA, enhanced Jurkat T cell survival. However, EST exhibited a dose-related cytotoxicity in the presence of UVA; up to 28% at 20 ng/ml. TE did not alter UVA-induced cytotoxicity. Since TE did not alter cell viability in the presence of UVA further damaging studies were not performed. COMET assay demonstrated the harmful effects of EST in the presence of UVA while EST without UVA had no significant effect on the nuclear damage. Apoptosis was not present as indicated by the absence of DNA laddering on agarose gel electrophoresis at 5ng/ml EST or TE ± UVA. Western blot showed that estrogen down regulated bcl-2 independently of UVA radiation while p53 was down regulated in the presence of UVA treatment. EST and TE have differential effects on UVA-induced cytotoxicity in Jurkat T-lymphocyte which suggested that women

  4. Photoprotective potential of strawberry (Fragaria × ananassa) extract against UV-A irradiation damage on human fibroblasts.

    Science.gov (United States)

    Giampieri, Francesca; Alvarez-Suarez, Josè M; Tulipani, Sara; Gonzàles-Paramàs, Ana M; Santos-Buelga, Celestino; Bompadre, Stefano; Quiles, José L; Mezzetti, Bruno; Battino, Maurizio

    2012-03-07

    Exposure to UV-A radiation is known to induce discrete lesions in DNA and the generation of free radicals that lead to a wide array of skin diseases. Strawberry (Fragaria × ananassa) contains several polyphenols with strong antioxidant and anti-inflammatory activities. Because the major representative components of strawberry are anthocyanins, these may significantly contribute to its properties. To test this hypothesis, methanolic extracts from the Sveva cultivar were analyzed for anthocyanin content and for their ability to protect human dermal fibroblasts against UV-A radiation, as assayed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenytetrazolium bromide and Comet assays. Five anthocyanin pigments were identified using high-performance liquid chromatography-diode array detection-electrospray ionization/mass spectrometry. Moreover, the strawberry extract showed a photoprotective activity in fibroblasts exposed to UV-A radiation, increasing cellular viability, and diminishing DNA damage, as compared to control cells. Overall, our data show that strawberry contains compounds that confer photoprotective activity in human cell lines and may protect skin against the adverse effects of UV-A radiation.

  5. Stimulation of the Fibrillar Collagen and Heat Shock Proteins by Nicotinamide or Its Derivatives in Non-Irradiated or UVA Radiated Fibroblasts, and Direct Anti-Oxidant Activity of Nicotinamide Derivatives

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    Neena Philips

    2015-05-01

    Full Text Available In skin aging, from intrinsic factors or exposure to ultraviolet (UV radiation, there is loss of structural fibrillar collagen and regulatory heat shock proteins. Phenolic compounds, with hydroxyl groups attached to an aromatic ring, have antioxidative and anti-inflammatory properties. Nicotinamide is an amide derivative of niacin or vitamin B3, with an amide linked to an aromatic ring, with UV absorptive, antioxidant, anti-inflammatory and anti-cell death/apoptosis properties. The goal of this research was to investigate the anti-skin aging mechanism of nicotinamide and its derivatives, 2,6-dihydroxynicotinamide, 2,4,5,6-tetrahydroxynicotinamide, and 3-hydroxypicolinamide (collectively niacin derivatives, through the stimulation of fibrillar collagens (type I, III and V, at protein and/or promoter levels and the expression of heat shock proteins (HSP-27, 47, 70, and 90 in non-irradiated or UVA radiated dermal fibroblasts; and from its direct antioxidant activity. UVA radiation inhibited the expression of types I and III collagen, and HSP-47 in dermal fibroblasts. The niacin derivatives significantly and similarly stimulated the expression of types I (transcriptionally, III and V collagens in non-irradiated, and UVA radiated fibroblasts indicating predominant effects. The 2,6-dihydroxynicotinamide had greater stimulatory effect on types I and III collagen in the non-irradiated, and UVA radiated fibroblasts, as well as greater direct antioxidant activity than the other niacin derivatives. The niacin derivatives, with a few exceptions, stimulated the expression of HSP-27, 47, 70 and 90 in non-irradiated, and UVA radiated fibroblasts. However, they had varied effects on the expression of the different HSPs in non-irradiated, and UVA radiated fibroblasts indicating non-predominant, albeit stimulatory, effect. Overall, nicotinamide and its derivatives have anti skin aging potential through the stimulation of fibrillar collagen and HSPs.

  6. Scleral Cross-Linking Using Riboflavin UVA Irradiation for the Prevention of Myopia Progression in a Guinea Pig Model: Blocked Axial Extension and Altered Scleral Microstructure.

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    Shuai Liu

    Full Text Available To develop methods of collagen cross-linking (CXL in the sclera for the treatment of progressive myopia and to investigate the biomechanical and histological changes that occur in as a result.Twenty 14-day-old guinea pigs were divided into 3 groups: the cross-linking group (CL, n = 8, non cross-linking group (NCL, n = 8, and control group (n = 4. The scleras of the right eyes of the guinea pigs in the CL group were surgically exposed and riboflavin was dropped onto the irradiation zone for 20 seconds prior to ultraviolet-A (UVA irradiation. The same procedure was conducted on the NCL group but without UVA irradiation. No procedure was conducted on the control group. The right eyes of the guinea pigs in the CL and NCL groups were then fitted with -10.00DS optics for six weeks. Retinoscopy and the axial lengths (AXL were measured at baseline, and at the second, fourth and sixth weeks post-treatment in all three groups. All animal subjects were euthanized after the sixth week and then biomechanical and histopathological examinations of the scleras were conducted.The mean AXL of the NCL group was longer than both the control and CL groups at six weeks (P = 0.001. The mean refractive error in the NCL group was statistically significantly more negative than both the control and the CL groups at six weeks (P = 0.001. The scleral collagen fiber arrangements of the CL and control groups were denser and more regularly distributed than the NCL group. Ultimate stress of the sclera was lowest in the NCL group, followed by the CL then the control group (P<0.05. Ultimate strain (% of the sclera was lowest in the CL group followed by the NCL and then the control group (P<0.05.Our study demonstrates that scleral CXL using riboflavin UVA irradiation effectively prevents the progression of myopia by increasing scleral biomechanical strength in a guinea pig model.

  7. Preparation and characterization of p–n heterojunction CuBi2O4/CeO2 and its photocatalytic activities under UVA light irradiation

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    Abdelkader Elaziouti

    2015-04-01

    Full Text Available CuBi2O4/CeO2 nanocomposites were synthesized by the solid state method and were characterized by a number of techniques such as X-ray diffraction, scanning electron microscopy and UV–Vis diffuse reflectance spectroscopy. The photocatalytic activity of the samples was investigated under UVA light and assessed using Congo red (CR dye as probe reaction. The efficiency of the coupled CuBi2O4/CeO2 photocatalyst was found to be related to the amount of added CuBi2O4 and to the pH medium. The CuBi2O4/CeO2 photocatalyst exhibited the high efficiency as a result of 83.05% of degradation of CR under UVA light for 100 min of irradiation time with 30 wt% of CuBi2O4 at 25 °C and pH 7, which is about 6 times higher than that of CeO2. The photodegradation reactions satisfactorily correlated with the pseudo-first-order kinetic model. The mechanism of the enhanced photocatalytic efficiency was explained by the heterojunction model.

  8. Solar ultraviolet radiation induces biological alterations in human skin in vitro: Relevance of a well-balanced UVA/UVB protection

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    Françoise Bernerd

    2012-01-01

    Full Text Available Cutaneous damages such as sunburn, pigmentation, and photoaging are known to be induced by acute as well as repetitive sun exposure. Not only for basic research, but also for the design of the most efficient photoprotection, it is crucial to understand and identify the early biological events occurring after ultraviolet (UV exposure. Reconstructed human skin models provide excellent and reliable in vitro tools to study the UV-induced alterations of the different skin cell types, keratinocytes, fibroblasts, and melanocytes in a dose- and time-dependent manner. Using different in vitro human skin models, the effects of UV light (UVB and UVA were investigated. UVB-induced damages are essentially epidermal, with the typical sunburn cells and DNA lesions, whereas UVA radiation-induced damages are mostly located within the dermal compartment. Pigmentation can also be obtained after solar simulated radiation exposure of pigmented reconstructed skin model. Those models are also highly adequate to assess the potential of sunscreens to protect the skin from UV-associated damage, sunburn reaction, photoaging, and pigmentation. The results showed that an effective photoprotection is provided by broad-spectrum sunscreens with a potent absorption in both UVB and UVA ranges.

  9. Transepithelial Phototherapeutic Keratectomy Using a 213-nm Solid-State Laser System Followed by Corneal Collagen Cross-Linking with Riboflavin and UVA Irradiation

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    George D. Kymionis

    2010-01-01

    Full Text Available Purpose. To present a case of a keratoconic patient who underwent epithelial removal with transepithelial phototherapeutic keratectomy (t-PTK using a 213-nm solid-state laser system followed by corneal collagen cross-linking (CXL with riboflavin and ultraviolet-A (UVA irradiation. Methods. Case report. Results. A twenty-four-year-old male with keratoconus underwent CXL treatment after epithelial removal with t-PTK using a solid-state laser system. No intra- or early postoperative complications were found. One month postoperatively, uncorrected visual acuity (UCVA improved from 20/63 to 20/32 while best spectacle- corrected visual acuity (BSCVA improved from 20/40 to 20/25. Corneal topography revealed a significant improvement which remained stable during the six-month followup period. Conclusions. Epithelial removal with t-PTK before CXL could improve patient's visual outcome.

  10. Corneal thickness changes during corneal collagen cross-linking with UV-A irradiation and hypo-osmolar riboflavin in thin corneas

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    Belquiz Amaral Nassaralla

    2013-06-01

    Full Text Available PURPOSE: To evaluate the thinnest corneal thickness changes during and after corneal collagen cross-linking treatment with ultraviolet-A irradiation, using hypo-osmolar riboflavin solution in thin corneas. METHODS: Eighteen eyes of 18 patients were included in this study. After epithelium removal, iso-osmolar 0.1% riboflavin solution was instilled to the cornea every 3 minutes for 30 minutes. Hypo-osmolar 0.1% riboflavin solution was then applied every 20 seconds for 5 minutes or until the thinnest corneal thickness reached 400 µm. Ultraviolet-A irradiation was performed for 30 minutes. During irradiation, iso-osmolar 0.1% riboflavin drops were applied every 5 minutes. Ultrasound pachymetry was performed at approximately the thinnest point of the cornea preoperatively, after epithelial removal, after iso-osmolar riboflavin instillation, after hypo-osmolar riboflavin instillation, after ultraviolet-A irradiation, and at 1, 6 and 12 months after treatment. RESULTS: Mean preoperative thinnest corneal thickness was 380 ± 11 µm. After epithelial removal it decreased to 341 ± 11 µm, and after 30 minutes of iso-osmolar 0.1% riboflavin drops, to 330 ± 7.6 µm. After hypo-osmolar 0.1% riboflavin drops, mean thinnest corneal thickness increased to 418 ± 11 µm. After UVA irradiation, it was 384 ± 10 µm. At 1, 6 and 12 months after treatment, it was 372 ± 10 µm, 381 ± 12.7, and 379 ± 15 µm, respectively. No intraoperative, early postoperative, or late postoperative complications were noted. CONCLUSIONS: Hypo-osmolar 0.1% riboflavin solution seems to be effective for swelling thin corneas. The swelling effect is transient and short acting. Corneal thickness should be monitored throughout the procedure. Larger sample sizes and longer follow-up are required in order to make meaningful conclusions regarding safety.

  11. Scleral crosslinking with riboflavin and ultraviolet A (UVA. A review

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    M. M. Bikbov

    2015-01-01

    Full Text Available Crosslinking is a formation of chemical bonds between large molecules. It makes material stronger. Corneal crosslinking with riboflavin and ultraviolet A (UVA has been successfully used in keratectasia treatment since 2003. There are some presuppositions of the scleral crosslinking successful using in the progressive myopia, characterized by thinning and mechanical strength decrease of the sclera, as well as in corneal ectasia. Experimental investigations showed an increase in the mechanical strength of the sclera after crosslinking with riboflavin and UVA in vitro. At the same time there were no changes in the thickness of the sclera. Achieved biomechanical effect was constant over a time with interval during up to 8 months in rabbits in vivo. Scleral structure changes after crosslinking were studied with light, electron and atomic force microscopy. Dense collagen bundle at the same time with fibers diameter increase was observed. The spatial pattern of fibrils within crosslinked scleral tissue was tangled and running in different directions. Some authors found such side effects of the procedure as damage of the retina and cornea on the irradiation side because of the high irradiance and thinning of the sclera as a result of dehydration. The optimal duration of riboflavin instillation (20 minutes and irradiation with 3 mW/cm² (40 minutes were determined in the experiments. It was shown in vivo, that crosslinking of the sclera with riboflavin and UVA prevented the growth of the rabbit eyes in occlusion-induced myopia. There are several data about successful clinical using of the scleral crosslinking. However, only 6 patients (12 eyes were observed, procedure parameters are not clear, follow-up period was only 6 months. Thus, now there are many unsolved questions about efficacy and safety of the scleral crosslinking with riboflavin and UVA. Experimental results encourage for a new method of the progressive myopia treatment will be

  12. The influence of light spectra, UV-A, and growth regulators on the in vitro seed germination of Senecio cineraria DC.

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    Cristiane Pimentel Victório

    2010-10-01

    Full Text Available This study was carried out to investigate the effects of light spectra, additional UV-A, and different growth regulators on the in vitro germination of Senecio cineraria DC. Seeds were surface-sterilized and inoculated in MS medium to evaluate the following light spectra: white, white plus UV-A, blue, green, red or darkness. The maximum germinability was obtained using MS0 medium under white light (30% and MS + 0.3 mg L-1 GA3 in the absence of light (30.5%. S. cineraria seeds were indifferent to light. Blue and green lights inhibited germination. Different concentrations of gibberellic acid (GA3 (0.1; 0.4; 0.6; 0.8; 1.0 and 2.0 mg L-1 and indole-3-acetic acid IAA (0.1; 0.3 and 1.0 mg L-1 were evaluated under white light and darkness. No concentration of GA3 enhanced seed germination percentage under white light. However, when the seeds were maintained in darkness, GA3 improved germination responses in all tested concentrations, except at 1.0 mg L-1. Under white light, these concentrations also increased the germination time and reduced germination rate. Germination rate, under light or darkness, was lower using IAA compared with GA3.

  13. Redox Mechanisms of AVS022, an Oriental Polyherbal Formula, and Its Component Herbs in Protection against Induction of Matrix Metalloproteinase-1 in UVA-Irradiated Keratinocyte HaCaT Cells

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    Thanyawan Pluemsamran

    2013-01-01

    Full Text Available Ayurved Siriraj HaRak (AVS022 formula has been used for topical remedy of dermatologic disorders. Oxidative stress induced by ultraviolet (UV A irradiation could be implicated in photoaged skin through triggering matrix metalloproteinase-1 (MMP-1. We, therefore, explored the antioxidant mechanisms by which AVS022 formulation and its individual components protected against UVA-dependent MMP-1 upregulation in keratinocyte HaCaT cells. TLC analysis revealed the presence of multiple phenolics including gallic acid (GA in the AVS022 extracts. We demonstrated that pretreatment with the whole formula and individual herbal components except T. triandra protected against increased MMP-1 activity in irradiated HaCaT cells. Moreover, all herbal extracts and GA, used as the reference compound, were able to reverse cytotoxicity, oxidant production, glutathione (GSH loss, and inactivation of catalase and glutathione peroxidase (GPx. F. racemosa was observed to yield the strongest abilities to abolish UVA-mediated induction of MMP-1 and impairment of antioxidant defenses including GSH and catalase. Our observations suggest that upregulation of endogenous antioxidants could be the mechanisms by which AVS022 and its herbal components suppressed UVA-stimulated MMP-1 in HaCaT cells. In addition, pharmacological actions of AVS022 formula may be attributed to the antioxidant potential of its components, in particular F. racemosa, and several phenolics including GA.

  14. Prediction of daily UV-A from daily global solar irradiance using the Ktuv and Kt clearness index; Prediccion de valores diarios de radiacion solar UV-A (295-385 nm) utilizando los indices de transparencia K{sub t}uv y K{sub t} y tecnicas de resdes neuronales artificiales

    Energy Technology Data Exchange (ETDEWEB)

    Barbero, F. J.; Lopez, G.; Batlles, F. J.

    2004-07-01

    In this work we compare two methodologies in order to estimate daily UV-A from daily global solar irradiance measurements. The first one is based on standard statistical procedures for relating the daily clearness indices Ktuv and Kt and the relative air mass, whereas the second methodology is based on the novel techniques of artificial neuronal networks. In both cases, we employed data recorded at the radiometric station located at the University of Almeria between 1993 and 1996. Both models are checked against data for years not previously used. (Author)

  15. Simultaneous chemical and photochemical protein crosslinking induced by irradiation of eye lens proteins in the presence of ascorbate: the photosensitizing role of an UVA-visible-absorbing decomposition product of vitamin C.

    Science.gov (United States)

    Avila, Felipe; Friguet, Bertrand; Silva, Eduardo

    2010-10-28

    Exposure to light has been implicated as a risk factor during aging of the eye lens and in cataract generation. In order to visualize the actual effect of UVA-visible light on this tissue, we incubated water-soluble eye lens proteins with ascorbate in the presence and absence of UVA-visible light for 3, 6 and 9 days at low oxygen concentration. The samples incubated in the presence of light were characterized by an initially small but continuous increase over time of the protein crosslinking. This was not the result of more extensive glycation because the decrease in amino group content of the proteins and the decomposition of ascorbate was the same in both irradiated and unirradiated samples. The augmented crosslinking capacity observed in the presence of UVA-visible light is due to the generation of a chromophore from the decomposition of ascorbate. This chromophore, obtained after 3, 6 and 9 days of incubation of solutions containing only ascorbate, induces both protein-crosslinking and oxidation after exposure to UVA-visible light in the presence of lens proteins. The extent of the crosslinking was proportional to the amount of the chromophore present in the solution. The presence of this chromophore was also determined when ascorbate was incubated with four-fold higher concentrations of N-α-acetyl lysine and N-α-acetyl arginine. When these samples were used as photosensitizers, the crosslinking degree was conditioned by the presence of this chromophore; nonetheless, the ascorbate-mediated advanced glycation end product (AGE) generation also made a contribution. The results of this work indicate that ascorbate oxidation, which generates the AGEs responsible for the chemical crosslinking of the lens proteins, also simultaneously produces a chromophore that can act as a photosensitizer, further increasing the protein crosslinking.

  16. In vitro antimicrobial activity of LED irradiation on Pseudomonas aeruginosa.

    Science.gov (United States)

    Petrini, Morena; Trentini, Paolo; Tripodi, Domenico; Spoto, Giuseppe; D'Ercole, Simonetta

    2017-03-01

    Pseudomonas aeruginosa is an opportunistic pathogen responsible of many deaths due to nosocomial pneumonia each year. It is particularly resistant to many different classes of antibiotics and disinfectants. For all these reasons, there is the necessity to find novel approaches of treatment. The aim of this study was to evaluate the effect of 880nm light emitting diodes (LED) irradiation on P. aeruginosa, in vitro. Different LED irradiation parameters (time, energy output and the addition of methylene blue and chlorhexidine) have been tested in order to evaluate the effects on this bacterium. After treatment, the colony forming units per milliliter (CFU mL-1) were recorded and the data were submitted to ANOVA and Bonferroni post hoc tests at a level of significance of 5%. A statistical significant reduction of bacterial count has been registered after 5min of LED irradiation. The antibacterial effect was directly proportional to irradiation time and the output energy. The pre-treatment with methylene blue, seems to be not effective against P. aeruginosa, independently from irradiation parameters. On the contrary, the contemporary action of LED and chlorhexidine has shown a great reduction of bacterial count that was statistical significant respect chlorhexidine and LED alone. The effect of LED irradiation was visible also after 24h, when a lower bacterial count characterized all irradiated samples respect controls. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Assessment of extracts of Helichrysum arenarium, Crataegus monogyna, Sambucus nigra in photoprotective UVA and UVB; photostability in cosmetic emulsions.

    Science.gov (United States)

    Jarzycka, Anna; Lewińska, Agnieszka; Gancarz, Roman; Wilk, Kazimiera A

    2013-11-05

    The aim of our study was to investigate the photoprotective activity and photostability efficacy of sunscreen formulations containing Helichrysum arenarium, Sambucus nigra, Crataegus monogyna extracts and their combination. UV transmission of the emulsion films was performed by using diffuse transmittance measurements coupling to an integrating sphere. In vitro photoprotection and photostability efficacy were evaluated according to the following parameters: sun protection factor (SPF), UVA protection factor (PF-UVA), UVA/UVB ratio and critical wavelength (λc) before and after UV irradiation. The results obtained show that the formulations containing polyphenols fulfill the official requirements for sunscreen products due to their broad spectrum of UV protection combined with their high photostability and remarkable antioxidant properties. Therefore H. arenarium, S. nigra, C. monogyna extracts represent useful additives for cosmetic formulation. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. In vitro irradiation station for broad beam radiobiological experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wera, A.-C., E-mail: anne-catharine.wera@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Centre for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP (Belgium); Riquier, H., E-mail: helene.riquier@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Unite de Recherche de Biologie Cellulaire (URBC), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium); Heuskin, A.-C., E-mail: anne-catherine.heuskin@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Centre for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP (Belgium); Michiels, C., E-mail: carine.michiels@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Unite de Recherche de Biologie Cellulaire (URBC), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium); Lucas, S., E-mail: stephane.lucas@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Centre for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP (Belgium)

    2011-12-15

    The study of the interaction of charged particles with living matter is of prime importance to the fields of radiotherapy, radioprotection and space radiobiology. Particle accelerators and their associated equipment are proven to be helpful tools in performing basic science in all these fields. Indeed, they can accelerate virtually any ions to a given energy and flux and let them interact with living matter either in vivo or in vitro. In this context, the University of Namur has developed a broad beam in vitro irradiation station for use in radiobiological experiments. Cells are handled in GLP conditions and can be irradiated at various fluxes with ions ranging from hydrogen to carbon. The station is mounted on a 2 MV tandem accelerator, and the energy range can be set up in the linear energy transfer (LET) ranges that are useful for radiobiological experiments. This paper describes the current status of the hardware that has been developed, and presents results related to its performance in term of dose-rate, energy range and beam uniformity for protons, alpha particles and carbon ions. The results of clonogenic assays of A549 lung adenocarcinoma cells irradiated with protons and alpha particles are also presented and compared with literature.

  19. In vitro irradiation station for broad beam radiobiological experiments

    Science.gov (United States)

    Wéra, A.-C.; Riquier, H.; Heuskin, A.-C.; Michiels, C.; Lucas, S.

    2011-12-01

    The study of the interaction of charged particles with living matter is of prime importance to the fields of radiotherapy, radioprotection and space radiobiology. Particle accelerators and their associated equipment are proven to be helpful tools in performing basic science in all these fields. Indeed, they can accelerate virtually any ions to a given energy and flux and let them interact with living matter either in vivo or in vitro. In this context, the University of Namur has developed a broad beam in vitro irradiation station for use in radiobiological experiments. Cells are handled in GLP conditions and can be irradiated at various fluxes with ions ranging from hydrogen to carbon. The station is mounted on a 2 MV tandem accelerator, and the energy range can be set up in the linear energy transfer (LET) ranges that are useful for radiobiological experiments. This paper describes the current status of the hardware that has been developed, and presents results related to its performance in term of dose-rate, energy range and beam uniformity for protons, alpha particles and carbon ions. The results of clonogenic assays of A549 lung adenocarcinoma cells irradiated with protons and alpha particles are also presented and compared with literature.

  20. Phyllosphere Methylobacterium bacteria contain UVA-absorbing compounds.

    Science.gov (United States)

    Yoshida, Shigenobu; Hiradate, Syuntaro; Koitabashi, Motoo; Kamo, Tsunashi; Tsushima, Seiya

    2017-02-01

    Microbes inhabiting the phyllosphere encounter harmful ultraviolet rays, and must develop adaptive strategies against this irradiation. In this study, we screened bacterial isolates originating from the phyllosphere of various plants which harbored absorbers of ultraviolet A (UVA), a wavelength range which is recognized as harmful to human skin. Of the 200 phyllosphere bacterial isolates we screened, methanol extracts from bacterial cells of seventeen isolates absorbed wavelengths in the range of 315-400nm. All of the UVA-absorbing strains belonged to Methylobacterium species based on 16S ribosomal RNA gene sequences, suggesting that cells of this bacterial genus contain specific UVA-absorbing compounds. When cells of a representative Methylobacterium strain were extracted using various solvents, UVA absorption was observed in the extracts obtained using several aqueous solvents, indicating that the UVA-absorbing compounds were highly polar. A compound was purified using solid columns and HPLC separation, and comparative analysis revealed that the absorption strength and spectrum of the compound were similar to those of the known UVA filter, avobenzone. The compound was also verified to be stable under UVA exposure for at least 480min. Based on these results, the UVA-absorbing compound harbored by Methylobacterium has potential to be used as a novel sunscreen ingredient. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Low-Dose UVA Radiation-Induced Adaptive Response in Cultured Human Dermal Fibroblasts

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    Zhongrong Liu

    2012-01-01

    Full Text Available Objective. To investigate the mechanism of the adaptive response induced by low-dose ultraviolet A (UVA radiation. Methods. Cultured dermal fibroblasts were irradiated by a lethal dose of UVA (86.4 J/cm2 with preirradiation of single or repetitive low dose of UVA (7.2 J/cm2. Alterations of cellular morphology were observed by light microscope and electron microscope. Cell cycle and cellular apoptosis were assayed by flow cytometer. The extent of DNA damage was determined by single-cell gel electrophoresis (SCGE. Results. The cultured dermal fibroblasts, with pretreatment of single or repetitive irradiation of 7.2 J/cm2 UVA relieved toxic reaction of cellular morphology and arrest of cell cycle, decreased apoptosis ratio, reduced DNA chain breakage, and accelerated DNA repair caused by subsequent 86.4 J/cm2 UVA irradiation. Compared with nonpretreatment groups, all those differences were significant (P<0.01 or P<0.05. Conclusions. The adaptation reaction might depend on the accumulated dose of low-dose UVA irradiation. Low-dose UVA radiation might induce adaptive response that may protect cultured dermal fibroblasts from the subsequent challenged dose of UVA damage. The duration and protective capability of the adaptive reaction might be related to the accumulated dose of low-dose UVA Irradiation.

  2. Genomic Integrity Detection of In Vitro Irradiated Banana Using Microsatellite Marker.

    OpenAIRE

    Nina Ratna Djuita; Rita Megia

    2010-01-01

    Genomic Integrity Detection of In Vitro Irradiated Banana Using Microsatellite Marker. The research aims todetect genomic integrity of in vitro irradiated banana using microsatellite marker. These studies were done on bananacv. Pisang Mas irradiated by 15 Gy of gamma ray. The DNA was isolated from each accesion following Dixie.Amplification of DNA products were done by Perkin Elmer Gene Amp PCR 2400 using ten primers, and thenelectroforesis in agarose 1%. Finally a vertical polyacrylamide gel...

  3. Prevention of UVA-induced oxidative damage in human dermal fibroblasts by new UV filters, assessed using a novel in vitro experimental system.

    Directory of Open Access Journals (Sweden)

    Francesca Brugè

    Full Text Available BACKGROUND: UVA rays present in sunlight are able to reach the dermal skin layer generating reactive oxygen species (ROS responsible for oxidative damage, alterations in gene expression, DNA damage, leading to cell inflammation, photo-ageing/-carcinogenesis. Sunscreens contain UV filters as active ingredients that absorb/reflect/dissipate UV radiation: their efficiency depends on their spectral profile and photostability which should then be reflected in biological protection of underlying skin. METHODS: A set of new UV filters was synthesized, and the most photostable one was compared to BMDBM, a widely used UVA filter. Cultured human dermal fibroblasts were exposed to UVA radiation which was filtered by a base cream containing or not UV filters placed above cell culture wells. The endpoints measured were: cell viability (MTT assay, ROS generation (DCFH-DA assay, mitochondrial function (JC-1 assay, DNA integrity (Comet assay and gene expression (MMP-1, COL1A1 by RT-qPCR. RESULTS: The new UV filter resulted more efficient than BMDBM in preserving cell viability, mitochondrial functionality and oxidative DNA damage, despite similar inhibition levels of intracellular ROS. Moreover, expression of genes involved in dermal photoageing were positively affected by the filtering action of the tested molecules. CONCLUSIONS: The experimental model proposed was able to validate the efficacy of the new UV filter, taking into account important cellular events related to UV-induced intracellular oxidative stress, often underestimated in the assessments of these compounds. GENERAL SIGNIFICANCE: The model may be used to compare the actual biological protection of commercial sunscreens and suncare products aside from their SPF and UVA-PF values.

  4. Ultraviolet light A irradiation induces immunosuppression associated with the generation of reactive oxygen species in human neutrophils

    Directory of Open Access Journals (Sweden)

    Cunbo Li

    2016-01-01

    Full Text Available Ultraviolet blood irradiation has been used as a physical therapy to treat many nonspecific diseases in clinics; however, the underlying mechanisms remain largely unclear. Neutrophils, the first line of host defense, play a crucial role in a variety of inflammatory responses. In the present work, we investigated the effects of ultraviolet light A (UVA on the immune functions of human neutrophils at the single-cell level by using an inverted fluorescence microscope. N-Formyl-methionyl-leucyl-phenylalanine (FMLP, a classic physiological chemotactic peptide, was used to induce a series of immune responses in neutrophils in vitro. FMLP-induced calcium mobilization, migration, and phagocytosis in human neutrophils was significantly blocked after treatment with 365nm UVA irradiation, demonstrating the immunosuppressive effects of UVA irradiation on neutrophils. Similar responses were also observed when the cells were pretreated with H2O2, a type of reactive oxygen species (ROS. Furthermore, UVA irradiation resulted in an increase in NAD(PH, a member of host oxidative stress in cells. Taken together, our data indicate that UVA irradiation results in immunosuppression associated with the production of ROS in human neutrophils.

  5. Eimeria tenella: in vitro development in irradiated bovine kidney cells

    Energy Technology Data Exchange (ETDEWEB)

    Crane, M.St.J.; Schmatz, D.M.; Stevens, S.; Habbersett, M.C.; Murray, P.K. (Merck Sharp and Dohme Research Labs., Rahway, NJ (USA))

    1984-06-01

    The initial infection and first-generation development of Eimeria tenella was quantified using a cloned MDBK (Madin-Darby Bovine Kidney) cell line, irradiated with gamma radiation prior to infection, as the host cell. Irradiated cell cultures were found to be more susceptible to infection and had a greater capacity to support parasite development than non-irradiated cultures. It was suggested that the larger proportion of cells in the G/sub 2/ phase of the cell cycle, the larger individual cell size and the inhibition of cell division in the irradiated cultures were all factors contributing to the increased susceptibility to infection and capacity to support parasite growth and development. The application of this technique (host cell irradiation) to the cultivation of other intracellular, protozoan parasites is discussed.

  6. Identification of protein phosphatase interacting proteins from normal and UVA-irradiated HaCaT cell lysates by surface plasmon resonance based binding technique using biotin-microcystin-LR as phosphatase capturing molecule.

    Science.gov (United States)

    Bécsi, Bálint; Dedinszki, Dóra; Gyémánt, Gyöngyi; Máthé, Csaba; Vasas, Gábor; Lontay, Beáta; Erdődi, Ferenc

    2014-09-05

    Identification of the interacting proteins of protein phosphatases is crucial to understand the cellular roles of these enzymes. Microcystin-LR (MC-LR), a potent inhibitor of protein phosphatase-1 (PP1), -2A (PP2A), PP4, PP5 and PP6, was biotinylated, immobilized to streptavidin-coupled sensorchip surface and used in surface plasmon resonance (SPR) based binding experiments to isolate phosphatase binding proteins. Biotin-MC-LR captured PP1 catalytic subunit (PP1c) stably and the biotin-MC-LR-PP1c complex was able to further interact with the regulatory subunit (MYPT1) of myosin phosphatase. Increased biotin-MC-LR coated sensorchip surface in the Surface Prep unit of Biacore 3000 captured PP1c, PP2Ac and their regulatory proteins including MYPT1, MYPT family TIMAP, inhibitor-2 as well as PP2A-A and -Bα-subunits from normal and UVA-irradiated HaCaT cell lysates as revealed by dot blot analysis of the recovered proteins. Biotin-MC-LR was used for the subcellular localization of protein phosphatases in HaCaT cells by identification of phosphatase-bound biotin-MC-LR with fluorescent streptavidin conjugates. Partial colocalization of the biotin-MC-LR signals with those obtained using anti-PP1c and anti-PP2Ac antibodies was apparent as judged by confocal microscopy. Our results imply that biotin-MC-LR is a suitable capture molecule in SPR for isolation of protein phosphatase interacting proteins from cell lysates in sufficient amounts for immunological detection. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. [Topical application of vitamins, phytosterols and ceramides. Protection against increased expression of interstital collagenase and reduced collagen-I expression after single exposure to UVA irradiation].

    Science.gov (United States)

    Grether-Beck, S; Mühlberg, K; Brenden, H; Krutmann, J

    2008-07-01

    Photoaged skin is characterized by a decrease of dermal collagen fibers, resulting from an increased breakdown and a diminished de novo synthesis. The increased breakdown results from an increased expression of matrix metalloproteinases (MMPs). The main building blocks involved in de novo synthesis of collagen fibers are collagen 1A1 and 1A2, the expression of which is reduced in photoaged skin. We studied the effect of topical application of vitamins, phytosterols and ceramides on UV-induced up-regulation of the expression of MMP-1 and on UV-induced down-regulation of COL1A1 and COL1A2. The study was conducted with 10 subjects with healthy skin who were comparatively treated for 10 days with (i) a basic preparation containing jojoba oil, (ii) the basic preparation supplemented with vitamins, (iii) the basic preparation supplemented with phytosterols and ceramides, and (iv) the basic preparation supplemented with vitamins, phytosterols and ceramides. All four preparations inhibited the UV induced up-regulation of MMP-1. Neither the basic product nor that supplemented with vitamins inhibited down-regulation of COL1A1 and COL1A2, but addition of phytosterols and ceramides caused a decreased down-regulation of the expression of these genes. Our results indicate that phytosterols and ceramides are effective in blocking the reduced collagen synthesis after UV irradiation and even stimulating synthesis. They may be useful additions to anti-aging products.

  8. Effects of low-level laser irradiation on human blood lymphocytes in vitro.

    Science.gov (United States)

    Al Musawi, Mustafa S; Jaafar, M S; Al-Gailani, B; Ahmed, Naser M; Suhaimi, Fatanah M; Suardi, Nursakinah

    2017-02-01

    Low-level laser irradiation (LLLI) has various effects on cultured human lymphocytes in vitro, but little is known about such effects in whole blood. This study investigated whether LLLI affected lymphocyte count in human whole blood in vitro. A total number of 130 blood samples were collected from apparently healthy adult patients through venipuncture into tubes containing EDTA. Each sample was divided into two equal aliquots to be used as a non-irradiated control sample and an irradiated sample. The irradiated aliquot was subjected to laser wavelengths of 405, 589, and 780 nm with different fluences of 36, 54, 72, and 90 J/cm2, at a fixed irradiance of 30 mW/cm2. A paired student t test was used to compare between non-irradiated and irradiated samples. The lymphocyte counts were measured using a computerized hematology analyzer and showed a significant (P irradiated samples. This increase in lymphocyte count upon irradiation was confirmed by flow cytometry. At a wavelength of 589 nm and fluence of 72 J/cm2, irradiation of whole blood samples showed a significant increase in CD45 lymphocytes and natural killer (NK) (CD16, CD56) cells, but no significant changes in CD3 T lymphocytes, T-suppressor (CD3, CD8) cells, T-helper (CD3, CD4) cells, and CD19 B lymphocytes when compared with their non-irradiated counterparts. Our results clearly demonstrate that NK cell count is altered by irradiation, which ultimately affects the whole lymphocyte count significantly.

  9. Characterization of the UVA protection provided by avobenzone, zinc oxide, and titanium dioxide in broad-spectrum sunscreen products.

    Science.gov (United States)

    Beasley, Donathan G; Meyer, Thomas A

    2010-12-01

    Solar UV radiation (UVR) is composed of UVB (290-320 nm) and UVA (320-400 nm) wavelengths. Only two sunscreen active ingredients approved in the US, avobenzone (butylmethoxydibenzoylmethane) and zinc oxide (ZnO), provide true broad-spectrum protection against UVA wavelengths >360 nm. Although effective against shorter UVR wavelengths sunscreen film during UVR exposure, avobenzone needs to be formulated into sunscreen products using sound formulation strategies. To characterize the efficacy of avobenzone, ZnO, and TiO(2) in terms of their abilities to provide broad UVA protection and to demonstrate the effectiveness of the different formulation strategies used today to maintain the efficacy of avobenzone even during prolonged exposures to UVR. UVA efficacy was assessed by measuring absorbance profiles in vitro using Vitro Skin® (IMS Inc., Orange, CT, USA) as an inert substrate and by determining UVA protection factors (PFA) on human skin. The impact of avobenzone loss on sun protection factor (SPF) and PFA values was evaluated by serially reducing avobenzone concentrations in an otherwise photostable product. The photostabilizing influence of specific formulation ingredients was monitored by measuring the extent to which they prevented UVR-induced degradation of avobenzone, whereas photostability of commercial sunscreen products was quantified by measuring the percentage change in absorbance within the UVB and UVA spectral regions following irradiation of thin product films on inert substrates. Model formulations containing 3% avobenzone or 5% ZnO provided superior attenuation of UVA wavelengths >360 nm compared with formulas containing 5% TiO(2). Additionally, sunscreen products of similar SPF containing avobenzone or ZnO exhibited significantly higher PFA values than those containing TiO(2). The addition of photostabilized avobenzone or ZnO increased PFA values nearly 3-fold, whereas the addition of TiO(2) increased PFA values only modestly. Judicious

  10. Photoprotection by dietary phenolics against melanogenesis induced by UVA through Nrf2-dependent antioxidant responses.

    Science.gov (United States)

    Chaiprasongsuk, Anyamanee; Onkoksoong, Tasanee; Pluemsamran, Thanyawan; Limsaengurai, Saowalak; Panich, Uraiwan

    2016-08-01

    Dietary phenolics may play a protective role in UV-mediated skin pigmentation through their antioxidant and UV-absorbing actions. In this study, we investigated whether genetic silencing of Nrf2, regulating the transcription of antioxidant genes, affected melanogenesis in primary human epidermal melanocytes (HEMn) and B16F10 melanoma cells subjected to UVA (8J/cm(2)) exposure. Then, we explored the antimelanogenic actions of phenolics; caffeic acid (CA) and ferulic acid (FA) providing partial UVA protection; quercetin (QU) and rutin (RU) providing strong UVA protection and; avobenzone (AV), an efficient UVA filter, in association with modulation of Nrf2-mediated antioxidant defenses in response to UVA insults in B16F10 cells. Upon oxidative insults, Nrf2 silencing promoted melanogenesis in both HEMn and B16F10 cells irradiated with UVA. Stimulation of melanogenesis by UVA correlated with increased ROS and oxidative DNA damage (8-OHdG), GSH depletion as well as a transient downregulation of Nrf2 nuclear translocation and of Nrf2-ARE signaling in B16F10 cells. All test compounds exerted antimelanogenic effects with respect to their abilities to reverse UVA-mediated oxidative damage as well as downregulation of Nrf2 activity and its target antioxidants (GCLC, GST and NQO1) in B16F10 cells. In conclusion, defective Nrf2 may promote melanogenesis under UVA irradiation through oxidative stress mechanisms. Compounds with antioxidant and/or UVA absorption properties could protect against UVA-induced melanogenesis through indirect regulatory effect on Nrf2-ARE pathway. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Protective effect of UV-A radiation during acclimation of the photosynthetic apparatus to UV-B treatment.

    Science.gov (United States)

    Štroch, Michal; Materová, Zuzana; Vrábl, Daniel; Karlický, Václav; Šigut, Ladislav; Nezval, Jakub; Špunda, Vladimír

    2015-11-01

    We examined the acclimation response of the photosynthetic apparatus of barley (Hordeum vulgare L.) to a combination of UV-A and UV-B radiation (UVAB) and to UV-B radiation alone. Our aim was to evaluate whether UV-A radiation prevents UV-B-induced damage to the photosynthetic apparatus and whether UV-A pre-acclimation is required to mitigate the negative influence of UV-B radiation. Barley plants were grown from seeds under low photosynthetically active radiation (50 μmol m(-2) s(-1)) either in the absence or presence of UV-A radiation (UVA- and UVA+ plants, respectively). After 8 days of development, plants were exposed simultaneously to UV-A and UV-B radiation for the next 6 days. Additionally, UVA- plants were exposed to UV-B radiation alone. The UVA+ plants had a higher CO2 assimilation rate near the light-saturation region (A(N)) and a higher content of both total chlorophylls (Chls) and total carotenoids than the UVA- plants. Chls content, A(N), the potential quantum yield of photosystem II (PSII) photochemistry (F(V)/F(M)), the capacity of light-induced thermal energy dissipation and the efficiency of excitation energy transfer within PSII remained the same or even increased in both UVA+ and UVA- plants after UVAB treatment. On the contrary, exposure of UVA- plants to UV-B radiation itself led to a reduction in all these characteristics. We revealed that the presence of UV-A radiation during UVAB treatment not only mitigated but completely eliminated the negative effect of UV-B radiation on the functioning of the photosynthetic apparatus and that UV-A pre-acclimation was not crucial for development of this UV-A-induced resistance against UV-B irradiation. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  12. The impact of natural sunlight exposure on the UVB-sun protection factor (UVB-SPF) and UVA protection factor (UVA-PF) of a UVA/UVB SPF 50 sunscreen.

    Science.gov (United States)

    Stephens, Thomas J; Herndon, James H; Colón, Luz E; Gottschalk, Ronald W

    2011-02-01

    To compare the functional stability of Cetaphil UVA/UVB Defense SPF 50 as measured by its ultraviolet B sun protection factor (UVB-SPF) and ultraviolet A protection factor (UVA-PF) values following exposure to natural sunlight versus the UVB-SPF and UVA-PF values of unexposed product. These two randomized, controlled, evaluator-blinded, single-center trials were conducted according to the methods outlined in the 2007 Proposed Amendment to the Final Monograph, “Sunscreen Drug Products for Over-the-Counter Human Use.” Sunscreen samples were applied to glass plates and exposed to ultraviolet radiation in the form of natural sunlight in four minimal erythemal doses (MED) ranging from 2–6 MED (42–36 mJ/cm2). Three test sites were identified on the back of each study subject. Exposed sunscreen (one of four doses), unexposed sunscreen, and a UVB-SPF 15 control sunscreen were applied to the three test sites in a randomized fashion, followed by UV irradiation of incremental doses. Erythema and pigment darkening responses were assessed immediately following UV exposure and again 16–24 hours (erythema) or three to 24 hours (pigment darkening) after exposure. UVB-SPF and UVA-PF values were calculated for the exposed and unexposed samples. The calculated UVB-SPF and UVA-PF values for all test samples (exposed and unexposed) were >50 and >9, respectively, which were greater than the stated UVB-SPF and UVA-PF values on the product label. No differences were observed between the exposed and unexposed samples in UVB-SPF or UVA-PF. The UVA and UVB protection using standard evaluation techniques of Cetaphil UVA/UVB Defense SPF 50 remains stable despite exposure of the sunscreen to natural sunlight containing UVB ranging from 2–16 MED (41–336 mJ/cm2) and coexistent UVA.

  13. In vitro antileishmanial properties of neutron-irradiated meglumine antimoniate

    Energy Technology Data Exchange (ETDEWEB)

    Borborema, Samanta Etel Treiger; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), SP (Brazil). Lab. de Biologia Molecular]. E-mail: samanta@usp.br; Osso Junior, Joao Alberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), SP (Brazil). Centro de Radiofarmacia]. E-mail: jaosso@ipen.br; Andrade Junior, Heitor Franco de [Instituto de Medicina Tropical de Sao Paulo (IMT-SP), SP (Brazil). Lab. de Protozoologia]. E-mail:hfandrad@usp.br

    2005-10-15

    Pentavalent antimony, as meglumine antimoniate (Glucantime) or sodium stibogluconate (Pentostam), is the main treatment for leishmaniasis, a complex of diseases caused by the protozoan Leishmania, and an endemic and neglected threat in Brazil. Despite over half a century of clinical use, their mechanism of action, toxicity and pharmacokinetic data remain unknown. The analytical methods for determination of antimony in biological systems remain complex and have low sensitivity. Radiotracer studies have a potential in pharmaceutical development. The aim of this study was to obtain a radiotracer for antimony, with suitable physical and biological properties. Meglumine antimoniate was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes {sup 122} Sb and {sup 124} Sb, with high radionuclidic purity and good specific activity. This compound showed the same antileishmanial activity as the native compound. The use of the radiotracers, easily created by neutron irradiation, could be an interesting tool to solve important questions in antimonial pharmacology. (author)

  14. Synergistic enhancement of in vitro irradiation by concomitant cisplatinum

    Energy Technology Data Exchange (ETDEWEB)

    Kigawa, Junzo; Kanamori, Yasunobu; Morishita, Kaichiro; Ishihara, Hiroshi; Minagawa, Yukihisa (Tottori Univ., Yonago (Japan). School of Medicine)

    1991-06-01

    The purpose of this study was to obtain information concerning combination therapy using irradiation with CDDP. The SKGIIIb strain of uterine cervical squamous cell carcinoma origin was used in this study. In cells exposed to CDDP, the ratio in the G{sub 1} G{sub 0} phase decreased until 48 hours after administration. Seventy two hours after administration, that in G{sub 1} G{sub 0} phase increased and that in S phase slightly decreased. Labeling indices increased particularly 48 hours after CDDP administration. The survival fraction rate at 24 hours after irradiation revealed a synergistic effect in those cells exposed to more than 0.2 Gy gamma rays 24, 48 and 72 hours after administration of CDDP. There were no significant differences in survival fraction rates among the three intervals prior to gamma-ray. SEM findings suggested that cell damage substantially increased with combined therapy. The results of the present study suggested that cell accumulation in S and G{sub 2}M phases, which were sensitive to irradiation, was induced by CDDP. The present report indicates therefore that combination therapy with radiation and CDDP will be useful in cancer treatment. (author).

  15. Proyecto de agronegocios uva isabella

    OpenAIRE

    María Emilia Muñoz

    2006-01-01

    Prestación que abaca información sobre el proyecto de agronegocios uva isabella, como parte del IV Taller de la Red de Proyectos de Integración Productiva - FOMIN, cuya finalidad es lograr la consolidación de la cadena productiva de la Uva Isabella en el Valle del Cauca, contribuyendo con ello a la reactivación económica de los pequeños productores de la zona.

  16. Genomic Integrity Detection of In Vitro Irradiated Banana Using Microsatellite Marker.

    Directory of Open Access Journals (Sweden)

    Nina Ratna Djuita

    2010-11-01

    Full Text Available Genomic Integrity Detection of In Vitro Irradiated Banana Using Microsatellite Marker. The research aims todetect genomic integrity of in vitro irradiated banana using microsatellite marker. These studies were done on bananacv. Pisang Mas irradiated by 15 Gy of gamma ray. The DNA was isolated from each accesion following Dixie.Amplification of DNA products were done by Perkin Elmer Gene Amp PCR 2400 using ten primers, and thenelectroforesis in agarose 1%. Finally a vertical polyacrylamide gel electroforesis was run and the products werevisualized by silver staining. The result shown that among the primers tested, eight primers produced clear, discrete,and reproducible bands. Number of DNA band exhibited ranging from one to two, following the ploidy level of pisangMas which is a diploid banana cultivar (AA. One band suggest homozygote allele while two bands showedheterozygote allele. Out of eight primers, six primers produced different allele among irradiated, in vitro, and in vivocontrol plant. Meanwhile, for the other two primers the allele were monomorph for all the accessions examined.Genomic modification was observed at all irradiated plants. The modification can happened at zygosity of certain allelethat may change from heterozygote to homozygote or vice versa. While modification in allele size that underlyinggenomic instability could be caused by several genetic events such as deletion, insertion, and amplification ofnucleotides.

  17. The Ablation Properties of CO2 Laser Irradiating to Absorption Media: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Sajee Sattayut

    2012-01-01

    Full Text Available This study aimed to compare histological affected zone of tissue samples irradiated by defocused CO2 laser at 1, 2, and 3W continuous wave with and without absorption media. The in vitro experiment was conducted in 70 tissue blocks. The samples were randomly allocated into 7 groups: 10 samples each group, namely, the groups irradiated with 1, 2, and 3W, defocused CO2 laser for 5 seconds, the groups irradiated with 1, 2, and 3W, defocused CO2 laser to the absorption media, and the media alone group as a control. Then the samples were stained with Masson’s trichrome and measured the affected borders under light microscope at 10 × 10 magnification. There was no histological alteration in the groups irradiated with the defocused CO2 laser to the absorption media while the groups without using the absorption media showed the tissue alteration by photoablation.

  18. Effects of speckle-like laser irradiation on growth of bacteria in vitro

    Science.gov (United States)

    Popov, A. Yu.; Popova, N. A.; Tyurin, A. V.; Grimblatov, V.

    2013-03-01

    In this work, for the first time, we have demonstrated the biological effects upon in vitro growth of bacteria and human peripheral blood erythrocytes of the irradiation with speckle-like highly-gradient laser light. Measurements of the growth of Staphylococcus aureus with and without antibiotic irradiated with uniform or interference pattern of intensity spatial distribution have shown strong dependence on the spatial frequency of the irradiation. Maximum inhibition of the bacteria growth was achieved at the frequency 1000 fringes/mm. It was also found that human blood erythrocytes exposure to such radiation at the power density typical for laser phototherapy could damage the erythrocytes. A possible explanation of the photo-biological effects of laser speckle irradiation relying on the electron-ion processes similar to those that occur under inhomogeneous illumination in inorganic media and called photo-stimulated diffusion of ions (Dember effect) is proposed and discussed.

  19. In Vitro Infectivity Study of Cryopreserved Irradiated Intraerythrocytic Form of Plasmodium falciparum

    Directory of Open Access Journals (Sweden)

    S. Nurhayati

    2017-12-01

    Full Text Available In control human malaria infection studies using irradiated Plasmodium falciparum, the cell bank of irradiated P. falciparum infected erythrocytes is needed. The cell banking methods represent an obvious way to obtain suitable material for blood stage Plasmodium. In a cell bank development of irradiated Plasmodium infected erythrocytes, the ability to cryopreserve procedure of Plasmodium is important to recover the infectivity of irradiated Plasmodium. This study aims at evaluating the in vitro infectivity of cryopreserved irradiated intra-erythrocytic form  P. falciparum. A protein profile investigation using Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE of cryopreserved  P. falciparum also conducted in this study to know the cryopreserved effect on the protein of irradiated P. falciparum. Plasmodium falciparum of 3D7 strain in human erythrocytes was maintained in invitro continuous culture. When the percentage of parasites was 10-20%, the culture was harvested and irradiated with gamma rays at a dose of 175 Gy. Irradiated P. falciparum then was mixed with cryopreserved solution and stored in -80 °C for one hour before transferred into liquid nitrogen for 20, 40 and 60 days. After being stored the irradiated P. falciparum was thawed and cultured for 20 days. The percentage of parasitaemia was enumerated by examining Giemsa stained thin blood films prepared for 20 days after initiation of culture. Results showed that storage time significantly (p<0.05 influence the percentage of parasitaemia. The cooling procedure and cryopreservation media may affect this study results. It also showed that there was insignificant difference of  P. falciparum protein profile in all storage times. Overall it can be assumed that the irradiated P. falciparum still kept their infectivity after stored in liquid nitrogen for 60 days. Further study using different cooling procedure and different formula of cryopreservation media with a

  20. In Vitro antileishmanial properties of neutron-irradiated meglumine antimoniate

    Directory of Open Access Journals (Sweden)

    Samanta Etel Treiger Borborema

    2005-10-01

    Full Text Available Pentavalent antimony, as meglumine antimoniate (Glucantime® or sodium stibogluconate (Pentostam® , is the main treatment for leishmaniasis, a complex of diseases caused by the protozoan Leishmania, and an endemic and neglected threat in Brazil. Despite over half a century of clinical use, their mechanism of action, toxicity and pharmacokinetic data remain unknown. The analytical methods for determination of antimony in biological systems remain complex and have low sensitivity. Radiotracer studies have a potential in pharmaceutical development. The aim of this study was to obtain a radiotracer for antimony, with suitable physical and biological properties. Meglumine antimoniate was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes 122Sb and 124Sb, with high radionuclidic purity and good specific activity. This compound showed the same antileishmanial activity as the native compound. The use of the radiotracers, easily created by neutron irradiation, could be an interesting tool to solve important questions in antimonial pharmacology.Os antimoniais pentavalentes, como o antimoniato de meglumina (Glucantime® ou estibogluconato de sódio (Pentostam® , são o principal tratamento para a leishmaniose, um complexo de doenças causadas pelo protozoário parasita Leishmania, uma doença endêmica e negligenciada no Brasil. Apesar do seu uso clínico por mais de meio século, seu mecanismo de ação, toxicidade e dados de farmacocinética permanecem desconhecidos. Os métodos analíticos para determinação de antimônio em sistemas biológicos são complexos e apresentam baixa sensibilidade. Estudos utilizando radiotraçadores têm papel potencial no desenvolvimento farmacológico. O objetivo deste estudo foi desenvolver um radiotraçador de antimônio, com propriedades físicas e biológicas adequadas. O antimoniato de meglumina foi irradiado por nêutrons no reator nuclear IEA-R1, produzindo dois radioisótopos: 122

  1. Mutation induction in chrysanthemum through in vitro acute and chronic irradiations with gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    Lamseejan, Siranut; Jompuk, Peeranuch [Kasetsart Univ., Faculty of Science, Bangkok (Thailand); Deeseepan, Surin [Maejo Univ., Office of Agricultural Research and Extension, Chiang Mai (Thailand)

    2002-02-01

    In Vitro culture of chrysanthemum variety 'Reagan Dark Splendid' was established using explants from axillary buds and ray florets. Shoots produced in vitro culture from axillary buds were irradiated with acute gamma rays of 30 Gy. While multiple shoots produced from in vitro culture of ray florets were irradiated with chronic gamma rays of 112 and 140 Gy. The irradiated shoots were then multiplied two times by single-node cuttings from M{sub 1}V{sub 1} to M{sub 1}V{sub 3}. Controls and irradiated shoots were rooted, transferred to soil in the greenhouse, and finally transplanted in the field. Observation and measurement were made at flowering time for height, number of nodes per plant and flower colour mutation frequency. Flower colour mutation frequency among the irradiated plants with 30, 112 and 140 Gy was 8.2, 9.3 and 15.3% respectively. Eleven variants were selected among the M{sub 1}V{sub 3} plants from 30 Gy dose treatment. Selected variants had flower colour varying from red, red-purple and yellow-orange. Nine variants were selected among the M{sub 1}V{sub 3} plants from 112 Gy dose treatment. Selected variants had flower colour varying from red, red-purple, purple and yellow-orange. Sixteen variants were selected from 140 Gy dose treatment. They had flower colour varying from red-purple, purple, orange-red, yellow-orange and yellow. These variants were multiplied through in vitro culture as well as by conventional cutting. They will be evaluated for their performance, stability and uniformity in the field, and for market value during the next planting season. (author)

  2. Psoralen-mediated virus photoinactivation in platelet concentrates: enhanced specificity of virus kill in the absence of shorter UVA wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Margolis-Nunno, Henrietta; Robinson, Richard; Horowitz, Bernard; Ben-Hur, Ehud [New York Blood Center, NY (United States); Geacintov, N.E. [New York Univ., NY (United States). Dept. of Chemistry

    1995-11-01

    Treatments with psoralens and long-wavelength ultraviolet radiation (UVA, 320-400 nm; PUVA) have shown efficacy for virus sterilization of platelet concentrates (PC). We have employed the psoralen derivative 4`-aminomethyl-4,5`,8-trimethylpsoralen (AMT), and have found that platelet integrity is best preserved when rutin, a flavonoid that quenches multiple reactive oxygen species, is present during AMT/UVA treatment of PC. In this report, we examine the effects of different UVA spectra under our standard PC treatment conditions (i.e. 50 {mu}g/mL AMT, 0.35 mM rutin and 38 J/cm{sup 2} UVA). Added vesicular stomatitis virus (VSV; {>=} 5.5 log{sub 10}) was completely inactivated with the simultaneous maintenance of the platelet aggregation response (> 90% of control) when a UVA light source with transmission mainly between 360 and 370 nm (narrow UVA1) was used. In contrast, with a broad-band UVA (320-400 nm; broad UVA) light source, the aggregation response was greatly compromised (< 50% of control) with only a minor increase in the rate of VSV kill. With this lamp, platelet function could be improved to about 75% of the control by adding a long-pass filter, which reduced the transmission of shorter ({<=} 345 nm) UVA wavelengths (340-400 nm; UVA1). At equivalent levels of virus kill, aggregation function was always best preserved when narrow UVA1 was used for PUVA treatment. Even in the absence of AMT, and with or without rutin present, narrow UVA1 irradiation was better tolerated by platelets than was broad UVA. (author).

  3. Purinergic signaling mediates oxidative stress in UVA-exposed THP-1 cells

    Directory of Open Access Journals (Sweden)

    Ayumi Kawano

    2015-01-01

    Full Text Available Ultraviolet A (UVA radiation, the major UV component of solar radiation, can penetrate easily to the dermis, where it causes significant damage to cellular components by inducing formation of reactive oxygen species (ROS. On the other hand, extracellular ATP is released in response to various stimuli, and activates purinergic P2X7 receptor, triggering ROS production and cell death. Here, we examined the hypothesis that ATP release followed by activation of P2X7 receptor plays a role in UVA-induced oxidative cell damage, using human acute monocytic leukemia cell line THP-1. Indeed, UVA irradiation of THP-1 cells induced ATP release and activation of P2X7 receptor. Irradiated cells showed a rapid increase of both p67phox in membrane fraction and intracellular ROS. Pretreatment with ecto-nucleotidase or P2X7 receptor antagonist blocked the UVA-initiated membrane translocation of p67phox and ROS production. Furthermore, pretreatment with antioxidant or P2X7 receptor antagonist efficiently protected UVA-irradiated cells from caspase-dependent cell death. These findings show that autocrine signaling through release of ATP and activation of P2X7 receptor is required for UVA-induced stimulation of oxidative stress in monocytes.

  4. Impact of UVA exposure on psychological parameters and circulating serotonin and melatonin

    Directory of Open Access Journals (Sweden)

    Sauermann Kirsten

    2002-04-01

    Full Text Available Abstract Background People tend to feel better after exposure to ultraviolet (UV radiation. This study was performed to investigate the impact of UVA exposure on psychological and neuroendocrine parameters. Methods Fifty-three volunteers were separated into 42 individuals who had UVA exposure and 11 individuals who had no UVA exposure. The UVA-exposed volunteers had irradiation sessions six times in a three-week period. All volunteers completed two questionnaires at baseline (T1 and at the end of the study (T3. For the determination of serotonin and melatonin serum levels of all volunteers blood samples were collected at baseline (T1, after the first UVA exposure (T2, and at the end of the study after the sixth exposure (T3. Results UVA-exposed volunteers felt significantly more balanced, less nervous, more strengthened, and more satisfied with their appearance at T3. By contrast, the controls did not show significant changes of psychological parameters. In comparison to T1 and T3, serum serotonin was significantly higher and the serum melatonin was significantly lower for the volunteers exposed to UVA at T2. Both, for exposed and non-exposed volunteers serotonin and melatonin levels did not significantly differ at T1 and T3. Conclusions It remains obscure, whether the exposure to UVA or other components of the treatment were responsible for the psychological benefits observed. The changes of circulating neuroendocrine mediators found after UVA exposure at T2 may be due to an UVA-induced effect via a cutaneous pathway. Nevertheless, the positive psychological effects observed in our study cannot be attributed to circulating serotonin or melatonin.

  5. Keratocyte apoptosis after corneal collagen cross-linking using riboflavin/UVA treatment.

    Science.gov (United States)

    Wollensak, Gregor; Spoerl, Eberhard; Wilsch, Michaela; Seiler, Theo

    2004-01-01

    Combined riboflavin/UVA treatment inducing collagen cross-links in the cornea has been shown to increase the biomechanical rigidity of the cornea and has been used successfully in the treatment of progressive keratoconus. The current study was undertaken to investigate the possible cytotoxic effect of combined riboflavin/UVA treatment on corneal keratocytes in vivo. Thirty-four New Zealand white rabbits were treated with 0.1% riboflavin solution and surface UVA irradiances ranging from 0.75 to 4 mW/cm2 (1.35- 7.2 J/cm2) for 30 minutes. The animals were euthanized either 4 (n = 6) or 24 (n = 28) hours postoperatively. Four additional control eyes underwent epithelial debridement alone. The corneas of the enucleated eyes were evaluated in routine histologic sections. In addition, the TUNEL technique and transmission electron microscopy were used for the detection of keratocyte apoptosis. In the control eyes with corneal epithelial debridement only, apoptotic keratocytes were found in the anterior 50 microm of the corneal stroma 4 hours postoperatively. However, riboflavin/UVA-induced apoptosis was only visible in the rabbit eyes enucleated 24 hours postoperatively. In these eyes, we found apoptosis of keratocytes down to a variable stromal depth depending on the applied UVA irradiance. A cytotoxic UVA irradiance for keratocytes in the range of 0.5-0.7 mW/cm2 could be deduced. Riboflavin/UVA treatment leads to a dose-dependent keratocyte damage that can be expected in human corneas down to a depth of 300 microm using a surface UVA dose of 5.4 J/cm2. Future studies should be done to examine the keratocyte repopulation and exclude possible adverse sequelae of keratocyte loss like stromal scarring or thinning.

  6. Characteristics of chrysanthemum mutants regenerated from in vitro explants irradiated with 12C5+ ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Nagatomi, Shigeaki [Laboratory of Radiation Biotechnology, Institute of Radiation Breeding, NIAR, MAFF, Tsukuba, Ibaraki (Japan)

    1998-12-31

    As most of the mutagens used for mutant varieties registered in Japan are gamma ray and x ray, it is necessary to develop new and efficient mutagens for plant mutation breeding. In this report, radiobiological effects of 12C5+ ion beam on in vitro cultured materials and mutation induction of flower color of regenerated plants are demonstrated, the results being compared with those from gamma ray irradiation. (J.P.N.)

  7. UVA-1 exposure in vivo leads to an IL-6 surge within the skin.

    Science.gov (United States)

    Schneider, Lars Alexander; Raizner, Katharina; Wlaschek, Meinhard; Brenneisen, Peter; Gethöffer, Kerstin; Scharffetter-Kochanek, Karin

    2017-09-01

    UVA-1 is a known promotor of skin ageing. Cytokines like IL-1α, Il-1β or TNF-α, VEGF and IL-6 orchestrate UV effects, and IL-6 is furthermore an effector of UVA-induced photoageing. We investigated how fractionated UVA-1 doses influence the cytokine milieu and especially the IL-6 levels in the skin in vivo. In a study with 35 participants, we exposed previously unirradiated human skin to three UVA-1 irradiation regimes. Cytokine levels in interstitial skin fluid were measured up to 48 hours postexposure and compared to unirradiated control skin fluid. Our results show that IL-6 levels increased significantly after UVA-1 exposure at selected time points. The other candidates IL-1α, Il-1β or TNF-α and VEGF show no significant response after UVA-1 exposure in vivo. UVA-1 thus raises selectively IL-6 levels in vivo, a fact that underlines its role in photoageing and has potential implications for its modulatory effect on photoageing pathology. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Stress response of Nidula niveo-tomentosa to UV-A light.

    Science.gov (United States)

    Taupp, Daniela E; Nimtz, Manfred; Berger, Ralf G; Zorn, Holger

    2008-01-01

    Exposition to UV-A light stimulated the growth and synthesis of raspberry ketone in submerged cultures of the basidiomycete Nidula niveotomentosa. To investigate the fungus' response to UV-A light differentially expressed proteins were identified by means of 2D-electrophoresis. Light induced proteins were de novo sequenced by ESI-MS/MS spectrometry, and the encoding nucleotide sequences were cloned from cDNA or genomic DNA. The spectrum of UV-A light-induced proteins comprised several stress-related proteins including a catalase, heat-shock proteins, glutathione S-transferases and proteasomes. In addition, growth-related enzymes of the citric cycle were found to be up-regulated as a response to irradiation with UV-A.

  9. Homogeneous UVA system for corneal cross-linking treatment

    Science.gov (United States)

    Ayres Pereira, Fernando R.; Stefani, Mario A.; Otoboni, José A.; Richter, Eduardo H.; Ventura, Liliane

    2010-02-01

    The treatment of keratoconus and corneal ulcers by collagen cross-linking using ultraviolet type A irradiation, combined with photo-sensitizer Riboflavin (vitamin B2), is a promising technique. The standard protocol suggests instilling Riboflavin in the pre-scratched cornea every 5min for 30min, during the UVA irradiation of the cornea at 3mW/cm2 for 30 min. This process leads to an increase of the biomechanical strength of the cornea, stopping the progression, or sometimes, even reversing Keratoconus. The collagen cross-linking can be achieved by many methods, but the utilization of UVA light, for this purpose, is ideal because of its possibility of a homogeneous treatment leading to an equal result along the treated area. We have developed a system, to be clinically used for treatment of unhealthy corneas using the cross-linking technique, which consists of an UVA emitting delivery device controlled by a closed loop system with high homogeneity. The system is tunable and delivers 3-5 mW/cm2, at 365nm, for three spots (6mm, 8mm and 10mm in diameter). The electronics close loop presents 1% of precision, leading to an overall error, after the calibration, of less than 10% and approximately 96% of homogeneity.

  10. Serum folate levels after UVA exposure: a two-group parallel randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Altmeyer Peter

    2001-11-01

    Full Text Available Abstract Background Photodegradation of certain vitamins such as riboflavins, carotinoids, tocopherol, and folate has been well-documented. Previous observations suggest that ultraviolet (UV radiation may cause folate deficiency. This is of great importance since folate deficiency is also known to be linked with the development of neural tube defects. To investigate the influence of UVA radiation on serum folate levels in vivo, we conducted a two-group randomised controlled trial on healthy subjects. Material and methods Twenty-four healthy volunteers with skin type II were enrolled into the study. Eight volunteers of the study population were randomly assigned to the control group. UVA irradiation was administered with an air-conditioned sunbed. Blood samples were taken from all volunteers at baseline (T1, 30 min after the first UVA exposure (T2, and at the end of the study 24 h after the sixth UV exposure (T3. The volunteers had two UVA exposures weekly within three weeks (cumulative UVA dose: 96 J/cm2. Volunteers of the control group had no UVA exposures. Serum folate was analysed with an automated immunoassay system. Results At all times of blood collection the differences between serum folate levels were insignificant (P > 0.05, except of the non-exposed controls at T2 (P 0.05. Conclusions Our data suggest that both single and serial UVA exposures do not significantly influence serum folate levels of healthy subjects. Therefore, neural tube defects claimed to occur after periconceptual UVA exposure are probably not due to UVA induced folate deficiency.

  11. Pilot Study for UVA-LED Disinfection of Escherichia coli in Water for Space and Earth Applications

    Science.gov (United States)

    Ragolta, Carolina

    2010-01-01

    To test the efficacy of UVA-LED disinfection, a solution of Escherichia coli was pumped through a modified drip flow reactor at a flow rate of 1 ml/min. The experiment was conducted in a controlled environment chamber to ensure that temperature did not cause disinfection. The reactor featured three wells with different treatments: UVA-LED irradiation, UVA-LEDs with Ti02, and UVA-LEDs with nanosilver. Samples from each well were taken throughout a 340 hour period, inactivated, assayed, and analyzed for E. coli disinfection. Results of the duplicate experiments indicated longer exposure times are needed for UVA-LED disinfection of E. coli in water. Further research would consider a longer sampling period and different test conditions, such as increased contact area and various flow rates.

  12. Preliminary results of proton beam characterization for a facility of broad beam in vitro cell irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wera, A.-C. [Laboratoire d' Analyses par Reactions Nucleaires (LARN), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium)], E-mail: anne-catherine.wera@fundp.ac.be; Donato, K. [Ion Beam Application, Chemin du Cyclotron 3, B-1348 Louvain-la-Neuve (Belgium); Michiels, C. [Unite de Recherche en Biologie Cellulaire (URBC), University of Namur-FUNDP (Belgium); Jongen, Y. [Ion Beam Application, Chemin du Cyclotron 3, B-1348 Louvain-la-Neuve (Belgium); Lucas, S. [Laboratoire d' Analyses par Reactions Nucleaires (LARN), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium)

    2008-05-15

    The interaction of charged particles with living matter needs to be well understood for medical applications. Particularly, it is useful to study how ion beams interact with tissues in terms of damage, dose released and dose rate. One way to evaluate the biological effects induced by an ion beam is by the irradiation of cultured cells at a particle accelerator, where cells can be exposed to different ions at different energies and flux. In this paper, we report the first results concerning the characterization of a broad proton beam obtained with our 2 MV tandem accelerator. For broad beam in vitro cell irradiation, the beam has to be stable over time, uniform over a {approx}0.5 cm{sup 2} surface, and a dose rate ranging from 0.1 to 10 Gy/min must be achievable. Results concerning the level of achievement of these requirements are presented in this paper for a 1 MeV proton beam.

  13. In vitro effects of helium-neon laser irradiation on human blood: blood viscosity and deformability of erythrocytes.

    Science.gov (United States)

    Mi, Xian-Qiang; Chen, Ji-Yao; Liang, Zi-Jun; Zhou, Lu-Wei

    2004-12-01

    The purpose of this study was to investigate the in vitro effects of He-Ne laser irradiation on some rheological factors of human blood, such as blood viscosity, erythrocyte deformability, and sedimentation rate. The intravascular irradiation of low power laser has been applied in pre-clinical and clinical to treat various pathological processes. However, the mechanism is not fully understood so far. Especially the interaction and related mechanism between the laser and blood are unclear. In this work, by measuring the change of the main rheological factors after laser irradiation, the interaction and mechanism were explored. A30-mW He-Ne laser was used for irradiation with a 4-5-mm-diameter beam spot on blood samples, with a fluence rate of about 150 mW/cm.(2) The irradiation time was 60 min, so the total dose of irradiation was 540 J/cm.(2) The pathological samples of blood were obtained from patients (volunteers), and each sample was divided into two tubes for irradiation and control. The blood viscosity, erythrocyte deformability, and sedimentation rate were measured after laser irradiation and compared with un-irradiated control. The blood samples with poor erythrocyte deformability were prepared by adding Ca(2+) to the normal erythrocytes of a healthy person for investigating the laser effect on erythrocyte deformability further. Laser irradiation reduced the erythrocyte sedimentation rate of blood samples, which had a hyper-sedimentation rate originally. The blood viscosity of samples in hyper-values was lowered by laser irradiation in all shear rates measured (10-110 S(-1)), with a relative variation of approximately 10%. The deformability of erythrocytes from pathological samples and Ca(2+)-treated samples was improved after laser irradiation. The positive effects of laser irradiation on improving the rheological properties of blood were demonstrated in vitro.

  14. Effects of lovastatin alone or combined with irradiation on tumor cells in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Gabrys, D. [Dept. of Radiation Oncology, Maria Sklodowska-Curie Memorial Cancer Center and Inst. of Oncology, Gliwice Branch (Poland); Dept. of Radiation Oncology, Medical Faculty Carl Gustav Carus, Univ. of Tech. Dresden (Germany); OncoRay Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Univ. of Tech. Dresden (Germany); Doerfler, A.; Yaromina, A.; Hessel, F.; Krause, M. [Dept. of Radiation Oncology, Medical Faculty Carl Gustav Carus, Univ. of Tech. Dresden (Germany); OncoRay Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Univ. of Tech. Dresden (Germany); Oertel, R. [Dept. of Clinical Pharmacology, Medical Faculty Carl Gustav Carus, Univ. of Tech. Dresden (Germany); Baumann, M. [Dept. of Radiation Oncology, Medical Faculty Carl Gustav Carus, Univ. of Tech. Dresden (Germany); OncoRay Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Univ. of Tech. Dresden (Germany); Experimental Center, Medical Faculty Carl Gustav Carus, Univ. of Tech. Dresden (Germany)

    2008-01-15

    Purpose: to evaluate the effect of lovastatin alone or combined with radiation on U87MG and FaDu cells in vitro and U87MG tumors in vivo. Material and methods: cell number, p21{sup WAF1} expression, apoptosis, reproductive cell death, and cell-cycle distribution were investigated after incubation of U87MG and FaDu cells in vitro. The effect of lovastatin (50 mg/kg/day) on tumor growth and on tumor growth delay after single-dose irradiation with 20 Gy was investigated using U87MG tumors in nude mice. Results: lovastatin dose dependently decreased cell number and proliferation of U87MG and FaDu cells. The proportion of cells in G0/G1 phase, apoptosis and p21 protein expression increased after lovastatin alone or combined with 4-Gy irradiation in both cell lines. Effects of lovastatin on cell cycle and cell number were more pronounced in U87MG compared to FaDu. No radiosensitization of clonogenic cells by lovastatin could be demonstrated in both cells lines, but the colony-forming ability after lovastatin alone was decreased in FaDu cells. In vivo, lovastatin decreased tumor volume over time but did not increase growth delay after irradiation of U87MG tumors with 20 Gy. Conclusion: the data support effects of lovastatin on proliferation, apoptosis and colony-forming ability in vitro and tumor volume in vivo. At the drug concentration achievable, lovastatin did not improve the effects of radiation on U87MG tumors in vivo. (orig.)

  15. Rat parotid cell function in vitro following x irradiation in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Bodner, L.; Kuyatt, B.L.; Hand, A.R.; Baum, B.J.

    1984-02-01

    The effect of X irradiation on rat parotid acinar cell function was evaluated in vitro 1, 3, and 7 days following in vivo exposure to 2000 R. Several cellular functions were followed: protein secretion (amylase release), ion movement (K/sup +/ efflux and reuptake), amino acid transport (..cap alpha..-amino(/sup 14/C)isobutyric acid), and an intermediary metabolic response ((/sup 14/C)glucose oxidation). In addition both the morphologic appearance and in vivo saliva secretory ability of parotid cells were assessed. Our results demonstrate that surviving rat parotid acinar cells, isolated and studied in vitro 1-7 days following 2000 R, remain functionally intact despite in vivo diminution of secretory function.

  16. Influence of UV-irradiation on enzymes in mouse ocular lens: in vitro studies

    Directory of Open Access Journals (Sweden)

    Jain Nayan

    1999-01-01

    Full Text Available Purpose: In vitro study of the enzymes involved in aerobic, anaerobic and hexose monophosphate shunt in ultraviolet radiation exposed mice lenses. Method: Of the selected enzymes, lactic dehydrogenase (LDH was representative of anaerobic glucose oxidation, succinic dehydrogenase (SDH of the aerobic oxidation, and Glucose-6-phosphate dehydrogenase (G-6-PDH of the Hexose Monophosphate (HMP shunt. Other enzymes studied were ATPase and glutathione reductase (GR. Results: Experiments with mice lenses in vitro showed that transparent lens became opaque following UV-irradiation at 360 nm. Opacification of the lens was accompanied by a change in enzyme activities for energy metabolism. Conclusion: These changes were progressive in a manner analogous to sequential morphological changes, which would be crucial in maintaining lens transparency.

  17. Diode Laser Irradiation in Endodontic Therapy through Cycles - in vitro Study

    Directory of Open Access Journals (Sweden)

    Trišić Dijana

    2017-07-01

    Full Text Available Background/Aim: The aim of this in vitro study was to investigate the influence of irradiation cycles and resting periods, on thermal effects on the external root surface during root canal irradiation of two diode laser systems (940 nm and 975 nm, at output powers of 1 W and 2 W in continuous mode. In previous studies the rising of temperature above 7°C has been reported as biologically accepted to avoid periodontal damage on the external root surface. Material and Methods: Twenty human inferior incisors were randomly distributed into four groups, the 940 nm, and the 975 nm diode laser irradiation, both with an output power of 1 W and 2 W, in continuous mode. The thermographic camera was used to detect temperature variations on the external root surface. Digital radiography of the samples was made. Results: After three cycles of irradiation, at apical third of the root, mean temperature variation by 940 nm diode laser irradiation was 2.88°C for output power of 1 W, and 6.52°C for output power of 2 W. The 975 nm laser caused a higher temperature increase in the apical region, with temperature variation of 13.56°C by an output power of 1 W, and 30.60°C at 2 W, with a statistical significance of p ≤ 0.0001 between two laser systems compared for the same power. The resting periods of 20 s between cycles were enough to lower temperature under 7°C in the case of 1 W and 2 W for 940 nm diode laser, while for 975 nm laser, after three irradiation cycles overheating occurred at both output power rates. Conclusion: Three cycles irradiation of 940 nm diode laser, with resting periods of 20 seconds, allowed safe usage of 1 W and 2 W in CW for endodontic treatment. For 975 nm at a power rate of 1 W, the last resting period drop the temperature near the safe limit and it came under 7°C in a period less than a minute, while at the power of 2 W the resting periods were not long enough for the safe temperature decrease.

  18. Antimicrobial effect of Er:YAG laser irradiation in infected root canals: an in vitro study

    Science.gov (United States)

    Sampaio Moura, Marcelo; Zanin, Fatima A. A.; Brugnera, Aldo, Jr.; Rodrigues de Araujo Estrela, Cyntia; Estrela, Carlos; Djalma Pecora, Jesus

    2003-06-01

    This study evaluated in vitro the antimicrobial action of Er:YAG laser in infected root canals. A total of 36 human anterior teeth were prepared, sterilized and inoculated with suspensions of S. aureus, E. faecalis, P aeruginosa, B. subtilis and C. albicans. After the contamination period (28 days), the teeth were irrigated with sterile distilled water or 1% sodium hypochlorite and, then, irradiated with an Er:YAG laser (wavelength 2094 nm) with two different evaluation parameters: 52 mJ and 110 mJ laser output at the fiber tip. After the irradiation, the teeth were irrigated with sterile distilled water and the solutions were collected with sterile paper points and incubated in Letheen Broth for 48 hours. After this period 0,1 ml of this solution was transferred to 10 ml of Brain Heart Infusion and incubated for 48 hours. After 72 hours a new collect ion was done and incubated again. Based on the data, it was concluded that the distilled water or 1% sodium hypochlorite irradiated or not with an Er:YAG laser with two different parameters: 10 Hz, 110 mJ input and 52 mJ output, and 10 Hz, 250 mJ input and 110 mJ output had no antimicrobial activity in the root canals contaminated with the following microorganisms: Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans.

  19. Inhibition of calcification of bovine pericardium after treatment with biopolymers, E-beam irradiation and in vitro endothelization

    Energy Technology Data Exchange (ETDEWEB)

    Polak, Roberta [Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of Sao Paulo, USP, Sao Paulo, SP (Brazil); Rodas, Andrea C.D. [Biotechnology Center, Energy and Nuclear Research Institute, IPEN-CNEN/SP, Sao Paulo, SP (Brazil); Chicoma, Dennis L.; Giudici, Reinaldo [Department of Chemical Engineering of Polytechnic School, University of Sao Paulo, SP (Brazil); Beppu, Marisa M. [School of Chemical Engineering, University of Campinas, UNICAMP, Campinas, SP (Brazil); Higa, Olga Z. [Biotechnology Center, Energy and Nuclear Research Institute, IPEN-CNEN/SP, Sao Paulo, SP (Brazil); Pitombo, Ronaldo N.M., E-mail: pitombo@usp.br [Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of Sao Paulo, USP, Sao Paulo, SP (Brazil)

    2013-01-01

    This work has investigated the in vitro calcification of bovine pericardium (BP) treated with chitosan (C), silk fibroin (SF) and electron beam irradiation after its endothelization in vitro. For this purpose, freeze-dried BP membranes treated with mixtures of C and SF (1:3, 1:1 and 3:1) and then irradiated by electron beam irradiation were seeded with human umbilical vein endothelial cells (HUVEC) in vitro. After 3 weeks of cultivation these membranes were submitted to in vitro calcification tests using simulated body fluid as the calcifying agent. Control membranes were also studied (without endothelial cells exposure). The results have shown that the membrane compatibility with HUVECs in vitro prevent such biomaterial from calcifying, showing a potential application in biomaterial area, such as cardiac valves and repair patches. - Highlights: Black-Right-Pointing-Pointer Bovine pericardium tissue treated with biopolymers followed by electron beam irradiation could be endothelized in vitro Black-Right-Pointing-Pointer Calcification was inhibited after endothelization, demonstrating a new anti calcifying treatment for BP membranes Black-Right-Pointing-Pointer This membranes could be used as cardiac valves and repair patches.

  20. Sensing and Responding to UV-A in Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Young-Ho Chung

    2012-12-01

    Full Text Available Ultraviolet (UV radiation can cause stresses or act as a photoregulatory signal depending on its wavelengths and fluence rates. Although the most harmful effects of UV on living cells are generally attributed to UV-B radiation, UV-A radiation can also affect many aspects of cellular processes. In cyanobacteria, most studies have concentrated on the damaging effect of UV and defense mechanisms to withstand UV stress. However, little is known about the activation mechanism of signaling components or their pathways which are implicated in the process following UV irradiation. Motile cyanobacteria use a very precise negative phototaxis signaling system to move away from high levels of solar radiation, which is an effective escape mechanism to avoid the detrimental effects of UV radiation. Recently, two different UV-A-induced signaling systems for regulating cyanobacterial phototaxis were characterized at the photophysiological and molecular levels. Here, we review the current understanding of the UV-A mediated signaling pathways in the context of the UV-A perception mechanism, early signaling components, and negative phototactic responses. In addition, increasing evidences supporting a role of pterins in response to UV radiation are discussed. We outline the effect of UV-induced cell damage, associated signaling molecules, and programmed cell death under UV-mediated oxidative stress.

  1. Sensing and Responding to UV-A in Cyanobacteria

    Science.gov (United States)

    Moon, Yoon-Jung; Kim, Seung Il; Chung, Young-Ho

    2012-01-01

    Ultraviolet (UV) radiation can cause stresses or act as a photoregulatory signal depending on its wavelengths and fluence rates. Although the most harmful effects of UV on living cells are generally attributed to UV-B radiation, UV-A radiation can also affect many aspects of cellular processes. In cyanobacteria, most studies have concentrated on the damaging effect of UV and defense mechanisms to withstand UV stress. However, little is known about the activation mechanism of signaling components or their pathways which are implicated in the process following UV irradiation. Motile cyanobacteria use a very precise negative phototaxis signaling system to move away from high levels of solar radiation, which is an effective escape mechanism to avoid the detrimental effects of UV radiation. Recently, two different UV-A-induced signaling systems for regulating cyanobacterial phototaxis were characterized at the photophysiological and molecular levels. Here, we review the current understanding of the UV-A mediated signaling pathways in the context of the UV-A perception mechanism, early signaling components, and negative phototactic responses. In addition, increasing evidences supporting a role of pterins in response to UV radiation are discussed. We outline the effect of UV-induced cell damage, associated signaling molecules, and programmed cell death under UV-mediated oxidative stress. PMID:23208372

  2. (Pheo)melanin photosensitizes UVA-induced DNA damage in cultured human melanocytes

    NARCIS (Netherlands)

    Wenczl, E.; Schans, G.P. van der; Roza, L.; Kolb, R.M.; Timmerman, A.J.; Smit, N.P.M.; Pavel, S.; Schothorst, A.A.

    1998-01-01

    The question of whether melanins are photoprotecting and/or photosensitizing in human skin cells continues to be debated. To evaluate the role of melanin upon UVA irradiation, DNA single-strand breaks (ssb) were measured in human melanocytes differing only in the amount of pigment produced by

  3. UVA and UVB in sunlight, Optimal Utilization of UV rays in Sunlight for phototherapy

    Directory of Open Access Journals (Sweden)

    Balasaraswathy P

    2002-01-01

    Full Text Available The disadvantages of sunlight as the source of UVA for phototherapy include variation with time, place, season, and atmospheric conditions. In the present study at Coimbatore, India we measured the UVa and UVB irradiance for one year using PMA 2100 meter. UVB irradiance was mazimum between 12.00 noon- 1.00 p.m (19.50µw/cm2 to 40.2µw/cm2 and UVA between 12 noon-1.15 p.m. (4.70mw/cm2 tp 6.59mw/cm2. The ratio of UVA was 1:500 to 1:600 during early hours and late evening and 1:200 during mid-day. At peak time (11.30 a.m. to 1.30 p.m., the exposure time for 1 June of UVA was 2 min. 32 sec. to 4 min. 31 sec and for 10mj of UVB it was from 4 min. 55 sec. to 11 min. 22 sec. We recommend the ideal time for UVB phototheraphy between 11.00 a.m. to 2.00 p.m. and for PUVASOL between 9.30 a.m. to 11 a.m. and 2 p.m. to 3.30 p.m. when incidental UVB and infrared rays responsible for heat are less.

  4. Growth of antarctic cyanobacteria under ultraviolet radiation: UVA counteracts UVB inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Quesada, A. [Universite Laval, Quebec (Canada)]|[Universidad Autonoma de Madrid (Spain); Mouget, J.L.; Vincent, W.F. [Universite Laval, Quebec (Canada)

    1995-04-01

    A mat-forming cyanobacterium (Phormidium murayi West and West) isolated from an ice-shelf pond in Antarctica was grown under white light combined with a range of UVA and UVB irradiance. The 4-day growth rate decreased under increasing ultraviolet (UV) radiation, with a ninefold greater response to UVB relative to UVA. In vivo absorbance spectra showed that UVA and to a greater extent UVB caused a decrease in phycocyanin/chlorophyll a and an increase in carotenoids/chlorophyll a. The phycocyanin/chlorophyll a ratio was closely and positively correlated to the UVB-inhibited growth rate. Under fixed spectral gradients of UV radiation, the growth inhibition effect was dominated by UVB. However, at specific UVB irradiances the inhibition of growth depended on the ratio of UVB to UVA, and growth rates increased linearly with increasing UVA. These results are consistent with the view that UVB inhibition represents the balance between damage and repair processes that are each controlled by separate wavebands. They also underscore the need to consider UV spectral balance in laboratory and field assays of UVB toxicity. 49 refs., 6 figs.

  5. Herpes simplex virus-1 entrapped in Candida albicans biofilm displays decreased sensitivity to antivirals and UVA1 laser treatment

    Directory of Open Access Journals (Sweden)

    Cristian Ascione

    2017-11-01

    Full Text Available Abstract Background Recently, we published data suggesting a mutualistic relationship between HSV-1 and Candida. albicans; in particular: (a HSV-1 infected macrophages are inhibited in their anti-Candida effector function and (b Candida biofilm protects HSV-1 from inactivation. The present in vitro study is aimed at testing the effects of Candida biofilm on HSV-1 sensitivity to pharmacological and physical stress, such as antiviral drugs (acyclovir and foscarnet and laser UVA1 irradiation. We also investigated whether fungus growth pattern, either sessile or planktonic, influences HSV-1 sensitivity to antivirals. Methods Mature Candida biofilms were exposed to HSV-1 and then irradiated with laser light (UVA1, 355 λ. In another set of experiments, mature Candida biofilm were co-cultured with HSV-1 infected VERO cells in the presence of different concentrations of acyclovir or foscarnet. In both protocols, controls unexposed to laser or drugs were included. The viral yield of treated and untreated samples was evaluated by end-point titration. To evaluate whether this protective effect might occur in relation with a different growth pattern, HSV-1 infected cells were co-cultured with either sessile or planktonic forms of Candida and then assessed for susceptibility to antiviral drugs. Results UVA1 irradiation caused a 2 Log reduction of virus yield in the control cultures whereas the reduction was only 1 Log with Candida biofilm, regardless to the laser dose applied to the experimental samples (50 or 100 J/cm2. The presence of biofilm increased the IC90 from 18.4–25.6 J/cm2. Acyclovir caused a 2.3 Log reduction of virus yield in the control cultures whereas with Candida biofilm the reduction was only 0.5 Log; foscarnet determined a reduction of 1.4 Log in the controls and 0.2 Log in biofilm cultures. Consequently, the ICs50 for acyclovir and foscarnet increased by 4- and 12-folds, respectively, compared to controls. When HSV-1 was exposed to

  6. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    Energy Technology Data Exchange (ETDEWEB)

    Taghinejad-Roudbaneh, M., E-mail: mtaghinejad@iaut.ac.i [Department of Animal Science, Faculty of Agriculture, Islamic Azad University, Tabriz Branch, P.O. Box 51589, Tabriz (Iran, Islamic Republic of); Ebrahimi, S.R. [Department of Animal Science, Faculty of Agriculture, Shahr-e-Qods Branch, Islamic Azad University, P.O. Box 37515-374, Shahr-e-Qods (Iran, Islamic Republic of); Azizi, S. [Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, P.O. Box 57155-1177, Urmia (Iran, Islamic Republic of); Shawrang, P. [Nuclear Science and Technology Research Institute, Agricultural, Medical and Industrial Research School, Atomic Energy Organization of Iran, P.O. Box 31485-498, Karaj (Iran, Islamic Republic of)

    2010-12-15

    The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased (P<0.01). From in situ results, irradiation of canola meal at doses of 45 kGy decreased (P<0.05) the effective degradibility of crude protein (CP) by 14%, compared with an untreated sample. In vitro CP digestibility of EB-irradiated canola meal at doses of 15 and 30 kGy was improved (P<0.05). Electrophoresis results showed that napin and cruciferin sub-units of 30 and 45 kGy EB-irradiated canola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal.

  7. Effects of ion beam irradiation on adventitious shoot regeneration from in vitro leaf explants of Septennial ionahta

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, L.B. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China)]. E-mail: libinzhou@impcas.ac.cn; Li, W.J. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Ma, S. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Dong, X.C. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Yu, L.X. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Li, Q. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Zhou, G.M. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Gao, Q.X. [Institute of Cell Biology, School of Life Science, Lanzhou University, Southern Tianshui Road 222, Lanzhou 730000 (China)

    2006-03-15

    The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiation on adventitious shoots from in vitro leaf explants of two different Saintpaulia ionahta (Mauve and Indikon) cultivars were studied with regard to tissue increase, shoots differentiation and morphology changes in the shoots. The experimental results showed that the survival fraction of shoot formation for the Mauve and Indikon irradiated with the carbon ion beam at 20 Gy were 0.715 and 0.600, respectively, while those for both the cultivars exposed to the X-ray irradiation at the same dose were 1.000. Relative biological effectiveness (RBE) of Mauve with respect to X-ray was about two. Secondly, the percentage of regenerating explants with malformed shoots in all Mauve regenerating explants irradiated with carbon ion beam at 20 Gy accounted for 49.6%, while that irradiated with the same dose of X-ray irradiation was only 4.7%; as for Saintpaulia ionahta Indikon irradiated with 20 Gy carbon ion beam, the percentage was 43.3%, which was higher than that of X-ray irradiation. Last, many chlorophyll deficient and other varieties of mutants were obtained in this study. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the leaf explants of Saintpaulia ionahta is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy to 25 Gy for carbon ion beam irradiation.

  8. Effects of ion beam irradiation on adventitious shoot regeneration from in vitro leaf explants of Saintpaulia ionahta

    Science.gov (United States)

    Zhou, L. B.; Li, W. J.; Ma, S.; Dong, X. C.; Yu, L. X.; Li, Q.; Zhou, G. M.; Gao, Q. X.

    2006-03-01

    The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiation on adventitious shoots from in vitro leaf explants of two different Saintpaulia ionahta (Mauve and Indikon) cultivars were studied with regard to tissue increase, shoots differentiation and morphology changes in the shoots. The experimental results showed that the survival fraction of shoot formation for the Mauve and Indikon irradiated with the carbon ion beam at 20 Gy were 0.715 and 0.600, respectively, while those for both the cultivars exposed to the X-ray irradiation at the same dose were 1.000. Relative biological effectiveness (RBE) of Mauve with respect to X-ray was about two. Secondly, the percentage of regenerating explants with malformed shoots in all Mauve regenerating explants irradiated with carbon ion beam at 20 Gy accounted for 49.6%, while that irradiated with the same dose of X-ray irradiation was only 4.7%; as for Saintpaulia ionahta Indikon irradiated with 20 Gy carbon ion beam, the percentage was 43.3%, which was higher than that of X-ray irradiation. Last, many chlorophyll deficient and other varieties of mutants were obtained in this study. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the leaf explants of Saintpaulia ionahta is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy to 25 Gy for carbon ion beam irradiation.

  9. The Effects of Gamma Irradiation on the Growth and Propagation of In-Vitro Chrysanthemum Shoot Explants (cv. Yellow Puma

    Directory of Open Access Journals (Sweden)

    I. Dwimahyani

    2010-08-01

    Full Text Available The study on the effect of gamma irradiation on in-vitro shoot growth of chrysanthemum cv. Yellow Puma has been carried out. The aim of the study was to observe genetic variability of shoot growth caused by gamma irradiation. Shoot explants with four leaves were irradiated by gamma with dose of 10, 15 and 20 Gy with 3 replications at each of dose. The irradiated shoot explants were then transferred into fresh MS solid medium and placed in a growth room. Observation was performed on number of leaves and branches on M1V0 generation, while plantlets height and number of branches were observed a M1V1 generation. Number of survival plantlets and multiplication rate on three subsequent subcultures were observed as well. Results showed that gamma rays with dose of 20 Gy inhibited growth of leaves as much as 50% compared to control (shoots without irradiation, and branches 73.7% in three weeks. Observation on multiplication rate at M1V1 generation showed that gamma irradiation with dose of 10 Gy promoted multiplication rate as much as 10% higher than control. It can be concluded that in vitro mutagenesis using gamma iradiation with dose of 10 to 15 Gy can be used for inducing genetic variability of chrysanthemum cv. Yellow Puma.

  10. Effects of Low-Level Laser Irradiation on the Pathogenicity of Candida albicans: In Vitro and in Vivo Study

    NARCIS (Netherlands)

    Seyedmousavi Tasieh, S.; Hashemi, S.J.; Rezaie, S.; Fateh, M.; Djavid, G.E.; Zibafar, E.; Morsali, F.; Zand, N.; Alinaghizadeh, M.; Ataie-Fashtami, L.

    2014-01-01

    Abstract Objective: The purpose of this study was to evaluate the effects of low-level laser irradiation (LLLI) on the in vitro growth characteristics and in vivo pathogenicity of Candida albicans in a murine model in the absence of a photosensitizer. Background data: C. albicans is an opportunistic

  11. Minibeam radiotherapy with small animal irradiators; in vitro and in vivo feasibility studies

    Science.gov (United States)

    Bazyar, Soha; Inscoe, Christina R.; O’Brian, E. Timothy; Zhou, Otto; Lee, Yueh Z.

    2017-12-01

    Minibeam radiation therapy (MBRT) delivers an ultrahigh dose of x-ray (⩾100 Gy) in 200–1000 µm beams (peaks), separated by wider non-irradiated regions (valleys) usually as a single temporal fraction. Preclinical studies performed at synchrotron facilities revealed that MBRT is able to ablate tumors while maintaining normal tissue integrity. The main purpose of the present study was to develop an efficient and accessible method to perform MBRT using a conventional x-ray irradiator. We then tested this new method both in vitro and in vivo. Using commercially available lead ribbon and polyethylene sheets, we constructed a collimator that converted the cone beam of an industrial irradiator to 44 identical beams (collimator size  ≈  4  ×  10 cm). The dosimetry characteristics of the generated beams were evaluated using two different radiochromic films (beam FWHM  =  246  ±  32 µm center-to-center  =  926  ±  23 µm peak-to-valley dose ratio  =  24.35  ±  2.10 collimator relative output factor  =  0.84  ±  0.04). Clonogenic assays demonstrated the ability of our method to induce radiobiological cell death in two radioresistant murine tumor cell lines (TRP  =  glioblastoma B16-F10  =  melanoma). A radiobiological equivalent dose (RBE) was calculated by evaluating the acute skin response to graded doses of MBRT and conventional radiotherapy (CRT). Normal mouse skin demonstrated resistance to doses up to 150 Gy on peak. MBRT significantly extended the survival of mice with flank melanoma tumors compared to CRT when RBE were applied (overall p  <  0.001). Loss of spatial resolution deep in the tissue has been a major concern. The beams generated using our collimator maintained their resolution in vivo (mouse brain tissue) and up to 10 cm deep in the radiochromic film. In conclusion, the initial dosimetric, in vitro and in vivo evaluations confirmed the

  12. Cytotoxicity and mutagenicity of opthalmic solution preservatives and UVA radiation in L5178Y cells

    Energy Technology Data Exchange (ETDEWEB)

    Withrow, T.J.; Brown, N.T.; Hitchins, V.M.; Strickland, A.G. (Food and Drug Administration, Rockville, MD (USA). Center for Devices and Radiological Health)

    1989-09-01

    Four preservatives used in ophthalmic solutions were tested for toxic and mutagenic potential in mouse lymphoma cells with and without exposure of cells to ultraviolet A (UVA) radiation. The preservatives tested were benzalkonium chloride (BAK), chlorhexidine, thimerosal and ethylenediaminetetraacetic acid (EDTA). Cell survival and mutagenesis were measured using the L5178Y mouse lymphoma (TK{sup +/-}) system. Cells were exposed to varying amounts of preservatives for 1 h at 37{sup 0}C, and aliquots irradiated with UVA radiation (during exposure to preservative). Cells were then assayed for survival, and mutagenesis at the thymidine kinase (TK) locus. In concentrations commonly found in ophthalmic solutions, BAK, chlorhexidine, and thimerosal were toxic to cells, and thimerosal was slightly mutagenic. When cells were exposed to preservative and UVA radiation, chlorhexidine was mutagenic and the mutagenic activity of thimerosal was enhanced. (author).

  13. Protective Effects of Resveratrol against UVA-Induced Damage in ARPE19 Cells

    Directory of Open Access Journals (Sweden)

    Chi-Ming Chan

    2015-03-01

    Full Text Available Ultraviolet radiation, especially UVA, can penetrate the lens, reach the retina, and induce oxidative stress to retinal pigment epithelial (RPE cells. Even though it is weakly absorbed by protein and DNA, it may trigger the production of reactive oxygen species (ROS and generate oxidative injury; oxidative injury to the retinal pigment epithelium has been implicated to play a contributory role in age-related macular degeneration (AMD. Studies showed that resveratrol, an abundant and active component of red grapes, can protect several cell types from oxidative stress. In this study, adult RPE cells being treated with different concentrations of resveratrol were used to evaluate the protective effect of resveratrol on RPE cells against UVA-induced damage. Cell viability assay showed that resveratrol reduced the UVA-induced decrease in RPE cell viability. Through flow cytometry analysis, we found that the generation of intracellular H2O2 induced by UVA irradiation in RPE cells could be suppressed by resveratrol in a concentration-dependent manner. Results of Western blot analysis demonstrated that resveratrol lowered the activation of UVA-induced extracellular signal-regulated kinase, c-jun-NH2 terminal kinase and p38 kinase in RPE cells. In addition, there was also a reduction in UVA-induced cyclooxygenase-2 (COX-2 expression in RPE cells pretreated with resveratrol. Our observations suggest that resveratrol is effective in preventing RPE cells from being damaged by UVA radiation, and is worth considering for further development as a chemoprotective agent for the prevention of early AMD.

  14. Are the surgeons safe during UV-A radiation exposure in collagen cross-linking procedure?

    Science.gov (United States)

    Shetty, Rashmi; Shetty, Rohit; Mahendradas, Padmamalini; Shetty, Bhujang K

    2012-02-01

    To quantify the effect of scattered UV-A radiation used in the collagen cross-linking (CXL) procedure and the amount of radiation reaching the surgeon and the surrounding area and to estimate the dampening effect by various protective devices. In this case series, 3 patients [aged 25-30 (±2.5) years] with keratoconus underwent a CXL procedure with UV-A light and riboflavin. Irradiance was measured using a spectrometer (Model USB2000; Ocean Optics, Inc) for various distances from the source, at various angles, and for different durations of radiation. The spectrometer was also used to measure the dampening effect produced by gown, latex gloves, and UV-protective glasses. Maximum UV-A radiation (1.4 × 10(-9) mW/cm(2)) was measured at 2 cm from the limbus, when the probe was held at a 45-degree angle to the floor. UV-A radiation reaching the surgeon's eye and the abdomen was 3.403 × 10(-11) and 2.36 × 10(-11) mW/cm(2), respectively. Gown, latex gloves, and UV-protective glasses showed dampening effects of 99.58%, 95.01%, and 99.73%, respectively. CXL appears to be a safe procedure with respect to UV-A radiation exposure to the surgeon. Further safety can be ensured by UV-protective devices.

  15. Singlet Oxygen-Mediated Oxidation during UVA Radiation Alters the Dynamic of Genomic DNA Replication.

    Directory of Open Access Journals (Sweden)

    Dany Graindorge

    Full Text Available UVA radiation (320-400 nm is a major environmental agent that can exert its deleterious action on living organisms through absorption of the UVA photons by endogenous or exogenous photosensitizers. This leads to the production of reactive oxygen species (ROS, such as singlet oxygen (1O2 and hydrogen peroxide (H2O2, which in turn can modify reversibly or irreversibly biomolecules, such as lipids, proteins and nucleic acids. We have previously reported that UVA-induced ROS strongly inhibit DNA replication in a dose-dependent manner, but independently of the cell cycle checkpoints activation. Here, we report that the production of 1O2 by UVA radiation leads to a transient inhibition of replication fork velocity, a transient decrease in the dNTP pool, a quickly reversible GSH-dependent oxidation of the RRM1 subunit of ribonucleotide reductase and sustained inhibition of origin firing. The time of recovery post irradiation for each of these events can last from few minutes (reduction of oxidized RRM1 to several hours (replication fork velocity and origin firing. The quenching of 1O2 by sodium azide prevents the delay of DNA replication, the decrease in the dNTP pool and the oxidation of RRM1, while inhibition of Chk1 does not prevent the inhibition of origin firing. Although the molecular mechanism remains elusive, our data demonstrate that the dynamic of replication is altered by UVA photosensitization of vitamins via the production of singlet oxygen.

  16. Effect of irradiation on gene expression of rat liver adhesion molecules. In vivo and in vitro studies

    Energy Technology Data Exchange (ETDEWEB)

    Moriconi, Federico; Malik, Ihtzaz; Ahmad, Ghayyor; Dudas, Joszef; Ramadori, Giuliano [Dept. of Gastroenterology and Endocrinology, Goettingen Univ. (Germany); Rave-Fraenk, Margret; Vorwerk, Hilke; Hille, Andrea; Hess, Clemens Friedrich; Christiansen, Hans [Dept. of Radiotherapy, Goettingen Univ. (Germany)

    2009-07-15

    Background and purpose: Migration of leukocytes into tissue is a key element of innate and adaptive immunity. An animal study showed that liver irradiation, in spite of induction of chemokine gene expression, does not lead to recruitment of leukocytes into the parenchyma. The aim of this study was to analyze gene expression of adhesion molecules, which mediate leukocyte recruitment into organs, in irradiated rat liver in vivo and rat hepatocytes in vitro. Material and methods: Rat livers in vivo were irradiated selectively at 25 Gy. Isolated hepatocytes in vitro were irradiated at 8 Gy. RNA extracted within 48 h after irradiation in vivo and in vitro was analyzed by real-time PCR (polymerase chain reaction) and Northern blot. Adhesion molecule concentration in serum was measured by ELISA (enzyme-linked immunosorbent assay). Cryostat sections of livers were used for immunohistology. Results: Significant radiation-induced increase of ICAM-1 (intercellular adhesion molecule-1), VCAM-1 (vascular cell adhesion molecule-1), JAM-1 (junctional adhesion molecule-1), {beta}{sub 1}-integrin, {beta}{sub 2}-integrin, E-cadherin, and P-selectin gene expression could be detected in vivo, while PECAM-1 (platelet-endothelial cell adhesion molecule-1) gene expression remained unchanged. In vitro, {beta}{sub 1}-integrin, JAM-1, and ICAM-2 showed a radiation-induced increased expression, whereas the levels of P-selectin, ICAM-1, PECAM-1, VCAM-1, Madcam-1 (mucosal addressin cell adhesion molecule-1), {beta}{sub 2}-integrin, and E-cadherin were downregulated. However, incubation of irradiated hepatocytes with either tumor necrosis factor-(TNF-){alpha}, interleukin-(IL-)1{beta}, or IL-6 plus TNF-{alpha} led to an upregulation of P-selectin, ICAM-1 and VCAM-1. Conclusion: The findings suggest that liver irradiation modulates gene expression of the main adhesion molecules in vivo and in cytokine-activated hepatocytes, with the exception of PECAM-1. This may be one reason for the lack of

  17. Comparison of the effects of photon versus carbon ion irradiation when combined with chemotherapy in vitro.

    Science.gov (United States)

    Schlaich, Fabian; Brons, Stephan; Haberer, Thomas; Debus, Jürgen; Combs, Stephanie E; Weber, Klaus-Josef

    2013-11-06

    Characterization of combination effects of chemotherapy drugs with carbon ions in comparison to photons in vitro. The human colon adenocarcinoma cell line WiDr was tested for combinations with camptothecin, cisplatin, gemcitabine and paclitaxel. In addition three other human tumour cell lines (A549: lung, LN-229: glioblastoma, PANC-1: pancreas) were tested for the combination with camptothecin. Cells were irradiated with photon doses of 2, 4, 6 and 8 Gy or carbon ion doses of 0.5, 1, 2 and 3 Gy. Cell survival was assessed using the clonogenic growth assay. Treatment dependent changes in cell cycle distribution (up to 12 hours post-treatment) were measured by FACS analysis after propidium-iodide staining. Apoptosis was monitored for up to 36 hours post-treatment by Nicoletti-assay (with qualitative verification using DAPI staining). All cell lines exhibited the well-known increase of killing efficacy per unit dose of carbon ion exposure, with relative biological efficiencies at 10% survival (RBE10) ranging from 2.3 to 3.7 for the different cell lines. In combination with chemotherapy additive toxicity was the prevailing effect. Only in combination with gemcitabine or cisplatin (WiDr) or camptothecin (all cell lines) the photon sensitivity was slightly enhanced, whereas purely independent toxicities were found with the carbon ion irradiation, in all cases. Radiation-induced cell cycle changes displayed the generally observed dose-dependent G2-arrest with little effect on S-phase fraction for all cell lines for photons and for carbon ions. Only paclitaxel showed a significant induction of apoptosis in WiDr cell line but independent of the used radiation quality. Combined effects of different chemotherapeutics with photons or with carbon ions do neither display qualitative nor substantial quantitative differences. Small radiosensitizing effects, when observed with photons are decreased with carbon ions. The data support the idea that a radiochemotherapy with common

  18. In vitro fertilization rate of mouse eggs with sperm after X-irradiation at various spermatogenetic stages

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Y.; Tobari, I.; Yamada, T. (National Inst. of Radiological Sciences, Chiba (Japan))

    1985-02-01

    The frequency of in vitro fertilization of mouse eggs using sperm obtained weekly (for 1-9 weeks) from epididymis after testicular X-irradiation (200 rad) was observed. The sperm concentrations for insemination were 100, 200 and 300/mm/sup 3/. The number of fertilized eggs seemed to remain constant almost at control level (90-98%) until the 4th week after X-irradiation. Thereafter, the number declined to reach a minimum level (about 30-50%) in the 6th week; they then recovered completely in the 8th week. This tendency was found at all sperm concentrations used. This result indicates that the most sensitive stage for the fertilization capacity of sperm to X-rays was the early spermatocytes or the late spermatogonia. The high radiosensitivity of the fertilization capacity of sperm irradiated during the early-spermatocyte to late-spermatogonial stage, corresponded well with the rate of induction of sperm abnormalities and spermatogenetic cell killing. The in vitro fertilization rate was not restored by an increase in sperm concentration at insemination; it is, therefore, likely that the in vitro fertilization frequency depends on the proportion of sperm with abnormal morphology and abnormal fertilization ability, and sperm number seems to have hardly any influence on the fertilization rate, as far as the in vitro fertilization experiment is concerned.

  19. Evaluation of UVA Cytotoxicity for Human Endothelium in an Ex Vivo Corneal Cross-linking Experimental Setting.

    Science.gov (United States)

    Mooren, Pepijn; Gobin, Laure; Bostan, Nezahat; Wouters, Kristien; Zakaria, Nadia; Mathysen, Danny G P; Koppen, Carina

    2016-01-01

    To evaluate endothelial cytotoxicity after exposure of human corneas to ultraviolet-A (UVA) (λ = 365 nm; 5.4 J/cm(2)) in an experimental ex vivo corneal cross-linking setting. Sixteen pairs of human donor corneas were cut into two pieces. One piece of each cornea was treated with 0.025% riboflavin solution prior to UVA irradiation (5 minutes; 18 mW/cm(2)), whereas the other piece was not irradiated but treated with riboflavin (right eye) or preservation medium (left eye). By irradiating from the endothelial side, the UVA dosage applied to endothelial cells exceeded at least eight times the cytotoxic threshold established in animal models (0.65 J/cm(2)). Endothelial cell counts were performed by two independent investigators after storage (4 to 5 days at 31 °C) and staining (trypan blue, alizarin red). Normality (Q-Q plot; Shapiro-Wilk test) and equivalence (mixed-effects modeling with a 10% equivalence threshold) of the endothelial cell counts of the different groups were evaluated. Equivalence of mean endothelial cell density between both groups was observed: 2,237 ± 208 cells/mm(2) in UVA-irradiated pieces and 2,290 ± 281 cells/mm(2) in control pieces (mean difference of 53 ± 240 cells/mm(2) between both groups). Despite direct irradiation of human donor endothelium using the clinical dosage for cross-linking, equivalence in endothelial cell counts was observed between irradiated tissues and controls. Ex vivo human corneal endothelial cells seem to be far more resistant to riboflavin-enhanced UVA irradiation than previously estimated by animal experiments. Copyright 2016, SLACK Incorporated.

  20. Myocardial temperature distribution under cw Nd:YAG laser irradiation in in vitro and in vivo situations: theory and experiment

    Science.gov (United States)

    Splinter, Robert; Littmann, Laszlo; Tuntelder, Jan R.; Svenson, Robert H.; Chuang, Chi Hui; Tatsis, George P.; Semenov, Serguei Y.; Nanney, Glenn A.

    1995-01-01

    Tissue samples ranging from 2 to 16 mm in thickness were irradiated at 1064 nm with energies ranging from 40 to 2400 J. Coagulation lesions of in vitro and in vivo experiments were subjected to temperature profiling and submitted for histology. Irreversible damage was calculated with the damage integral formalism, following the bioheat equation solved with Monte Carlo computer light-distribution simula-tions. Numerical temperature rise and coagulation depth compared well with the in vitro results. The in vivo data required a change in the optical properties based on integrating sphere measurements for high irradiance to make the experimental and numerical data converge. The computer model has successfully solved several light-tissue interaction situations in which scattering dominates over absorption.

  1. Induction of mutation on mulberry (morus alba L.) by using in vitro techniques in combination with gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Van Vinh [Nuclear Research Institute, Department of Biotechnology, Dalat (Viet Nam)

    2001-03-01

    Mutation induction and selection of desired characters on mulberry will contribute to industrialization and modernization in agricultural development in Vietnam. The objectives are to conduct biochemical and physiological analyses of collected mulberry varieties and to improve techniques for boosting yield and better quality in some mulberry genotypes by using in vitro technique combined with gamma irradiation. Two mulberry varieties named BauDen and VA 186 were used. Cuts of them were treated with gamma rays of Co-60, cultivated in experimental field with use of vitro technique to rapidly isolate mutants in irradiated population and investigated for plantlets, color of leaves, etc 30 days after cultivation. The results on the mutation frequency and spectrum of variation as well as the results of selection and isolation are presented. Eleven mutated clones from the two starting varieties were obtained during 1993-99. Three of them are now being cultivated in LamDong province fields. (S. Ohno)

  2. High-power helium-neon laser irradiation inhibits the growth of traumatic scars in vitro and in vivo.

    Science.gov (United States)

    Shu, Bin; Ni, Guo-Xin; Zhang, Lian-Yang; Li, Xiang-Ping; Jiang, Wan-Ling; Zhang, Li-Qun

    2013-05-01

    This study explored the inhibitory effect of the high-power helium-neon (He-Ne) laser on the growth of scars post trauma. For the in vitro study, human wound fibroblasts were exposed to the high-power He-Ne laser for 30 min, once per day with different power densities (10, 50, 100, and 150 mW/cm(2)). After 3 days of repeated irradiation with the He-Ne laser, fibroblast proliferation and collagen synthesis were evaluated. For in vivo evaluation, a wounded animal model of hypertrophic scar formation was established. At postoperative day 21, the high-power He-Ne laser irradiation (output power 120 mW, 6 mm in diameter, 30 min each session, every other day) was performed on 20 scars. At postoperative day 35, the hydroxyproline content, apoptosis rate, PCNA protein expression and FADD mRNA level were assessed. The in vitro study showed that the irradiation group that received the power densities of 100 and 150 mW/cm(2) showed decreases in the cell proliferation index, increases in the percentage of cells in the G0/G1 phase, and decreases in collagen synthesis and type I procollagen gene expression. In the in vivo animal studies, regions exposed to He-Ne irradiation showed a significant decrease in scar thickness as well as decreases in hydroxyproline levels and PCNA protein expression. Results from the in vitro and in vivo studies suggest that repeated irradiation with a He-Ne laser at certain power densities inhibits fibroblast proliferation and collagen synthesis, thereby inhibits the growth of hypertrophic scars.

  3. The In Vitro Response of Tissue Stem Cells to Irradiation With Different Linear Energy Transfers

    Energy Technology Data Exchange (ETDEWEB)

    Nagle, Peter W.; Hosper, Nynke A. [Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Ploeg, Emily M. [Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Goethem, Marc-Jan van [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); KVI-Center for Advanced Radiation Research, University of Groningen, Groningen (Netherlands); Brandenburg, Sytze [KVI-Center for Advanced Radiation Research, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Chiu, Roland K. [Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Coppes, Robert P., E-mail: r.p.coppes@umcg.nl [Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)

    2016-05-01

    Purpose: A reduction in the dose, irradiated volume, and sensitivity of, in particular, normal tissue stem cells is needed to advance radiation therapy. This could be obtained with the use of particles for radiation therapy. However, the radiation response of normal tissue stem cells is still an enigma. Therefore, in the present study, we developed a model to investigate the in vitro response of stem cells to particle irradiation. Methods and Materials: We used the immortalized human salivary gland (HSG) cell line resembling salivary gland (SG) cells to translate the radiation response in 2-dimensional (2D) to 3-dimensional (3D) conditions. This response was subsequently translated to the response of SG stem cells (SGSCs). Dispersed single cells were irradiated with photons or carbon ions at different linear energy transfers (LETs; 48.76 ± 2.16, 149.9 ± 10.8, and 189 ± 15 keV/μm). Subsequently, 2D or 3D clonogenicity was determined by counting the colonies or secondary stem cell-derived spheres in Matrigel. γH2AX immunostaining was used to assess DNA double strand break repair. Results: The 2D response of HSG cells showed a similar increase in dose response to increasing higher LET irradiation as other cell lines. The 3D response of HSG cells to increasing LET irradiation was reduced compared with the 2D response. Finally, the response of mouse SGSCs to photons was similar to the 3D response of HSG cells. The response to higher LET irradiation was reduced in the stem cells. Conclusions: Mouse SGSC radiosensitivity seems reduced at higher LET radiation compared with transformed HSG cells. The developed model to assess the radiation response of SGSCs offers novel possibilities to study the radiation response of normal tissue in vitro.

  4. Effects of CO2 laser irradiation on matrix-rich biofilm development formation–an in vitro study

    Directory of Open Access Journals (Sweden)

    Bruna Raquel Zancopé

    2016-11-01

    Full Text Available Background A carbon dioxide (CO2 laser has been used to morphologically and chemically modify the dental enamel surface as well as to make it more resistant to demineralization. Despite a variety of experiments demonstrating the inhibitory effect of a CO2 laser in reduce enamel demineralization, little is known about the effect of surface irradiated on bacterial growth. Thus, this in vitro study was preformed to evaluate the biofilm formation on enamel previously irradiated with a CO2 laser (λ = 10.6 µM. Methods For this in vitro study, 96 specimens of bovine enamel were employed, which were divided into two groups (n = 48: 1 Control-non-irradiated surface and 2 Irradiated enamel surface. Biofilms were grown on the enamel specimens by one, three and five days under intermittent cariogenic condition in the irradiated and non-irradiated surface. In each assessment time, the biofilm were evaluated by dry weigh, counting the number of viable colonies and, in fifth day, were evaluated by polysaccharides analysis, quantitative real time Polymerase Chain Reaction (PCR as well as by contact angle. In addition, the morphology of biofilms was characterized by fluorescence microscopy and field emission scanning electron microscopy (FESEM. Initially, the assumptions of equal variances and normal distribution of errors were conferred and the results are analyzed statistically by t-test and Mann Whitney test. Results The mean of log CFU/mL obtained for the one-day biofilm evaluation showed that there is statistical difference between the experimental groups. When biofilms were exposed to the CO2 laser, CFU/mL and CFU/dry weight in three day was reduced significantly compared with control group. The difference in the genes expression (Glucosyltransferases (gtfB and Glucan-binding protein (gbpB and polysaccharides was not statically significant. Contact angle was increased relative to control when the surface was irradiated with the CO2 laser. Similar

  5. Voriconazole N-oxide and its UVB photoproduct sensitize keratinocytes to UVA

    Science.gov (United States)

    Ona-Vu, K.; Oh, D.H.

    2015-01-01

    Background The antifungal agent, voriconazole, is associated with phototoxicity and photocarcinogenicity. Prior work has indicated that voriconazole and its hepatic N-oxide metabolite do not sensitize keratinocytes to ultraviolet B (UVB). Clinical observations have suggested ultraviolet A (UVA) may be involved. Objectives To determine the photochemistry and photobiology of voriconazole and its major hepatic metabolite, voriconazole N-oxide. Methods Voriconazole and voriconazole N-oxide were spectrophotometrically monitored following various doses of UVB. Cultured human keratinocytes were treated with parental drugs or with their UVB photoproducts, and survival following UVA irradiation was measured by thiazolyl blue metabolism. Reactive oxygen species and 8-oxoguanine were monitored by fluorescence microscopy. Results Voriconazole and voriconazole N-oxide have varying ultraviolet B (UVB) absorption but do not acutely sensitize cultured human keratinocytes following UVB exposure. However, sustained UVB exposures produced notable dose- and solvent-dependent changes in the absorption spectra of voriconazole N-oxide which in aqueous solution acquires a prominent ultraviolet A (UVA) absorption band, suggesting formation of a discrete photoproduct. Neither the parental drugs nor their photoproducts sensitized cells to UVB though all but voriconazole N-oxide were moderately toxic to cells in the dark. Notably, both voriconazole N-oxide and its UVB photoproduct, but not voriconazole or its photoproduct, additionally sensitized cells to UVA by >3-fold relative to controls in association with UVA-induced reactive oxygen species and 8-oxoguanine levels. Conclusions Voriconazole N-oxide and its UVB-photoproduct act as UVA-sensitizers that generate reactive oxygen species and that produce oxidative DNA damage. These results suggest a mechanism for the phototoxicity and photocarcinogenicity observed with voriconazole treatment. PMID:25919127

  6. Differential responses to x-irradiation of subpopulations of two heterogeneous human carcinomas in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Leith, J.T.; Dexter, D.L.; DeWyngaert, J.K.; Zeman, E.M.; Chu, M.Y.; Calabresi, P.; Glicksman, A.S.

    1982-07-01

    The responses of two heterogeneous human cancer cell lines and their derivative clones to graded single doses of X-rays were examined in vitro. One system consisted of the human colon carcinoma line DLD-1 and two subpopulations (clones A and D). The second system consisted of the human lung carcinoma line (LX1) and four subpopulations (LX1-1, LX1-2, LX1-3, and LX1-9). These subpopulations have previously been shown to be markedly heterogeneous in terms of such characteristics as karyotype, morphology, drug sensitivity, tumorigenicity, and expression of membrane glycoproteins (such as carcinoembryonic antigen and tumor colonic mucoprotein antigen). Exponentially growing cultures were irradiated with graded single doses of 100-kVp X-rays. Survival was assessed using colony formation as the end point, and responses from multiple experiments were fitted to the single-hit, multitarget equation of cell survival. Values for the mean lethal dose (D0, grays), quasithreshold dose (Dq, grays), and extrapolation number (n) were obtained. For the human colon adenocarcinoma system, these values for the three tumor lines were: DLD-1, 0.95, 2.34, and 11.7; clone A, 1.06, 2.23 and 8.20; and clone D, 1.08, 1.89, and 5.80. For the human lung carcinoma system, these values for the five sublines were: LX1, 1.14, 0.19, and 1.20; LX1-1, 0.96, 2.06, and 8.54; LX1-2, 0.98, 0.88, and 2.48; LX1-3, 0.68, 2.05, and 20.3; and LX1-9, 1.12, 0.00, and 1.00. These two human tumor systems therefore exhibit variability in their intrinsic sensitivity to X-irradiation. The data indicate that failure of some human carcinomas to respond to physical treatment modalities can be due to preexisting resistant subpopulations.

  7. Lenses from Brown‐Norway pigmented rats are more tolerant to in vitro ultraviolet irradiation than lenses from Fischer‐344 albino rats

    National Research Council Canada - National Science Library

    Löfgren, Stefan

    2012-01-01

    ...) cataractogenesis between pigmented and albino rats can be seen also with in vitro irradiation. The shielding effect of the iris and UVR absorption in the anterior segment is nullified, and inherent differences in lenticular UVR...

  8. Effect of LED irradiation on the expression of MMP-3 and MMP-13 in SW1353 cells in vitro

    Science.gov (United States)

    Zeng, Chang-chun; Guo, Zhou-yi; Zhang, Feng-xue; Deng, Wen-di; Liu, Song-hao

    2007-05-01

    Matrix Metalloproteinase (MMP) plays an active role in remodeling cartilage in osteoarthritic cartilage. To find an effective method of prevention of osteoclasia, this in vitro study focuses on the expression of MMP-3 and MMP-13 in the SW1353 cells by LED irradiation. The human chondrosarcoma cell line SW1353 were stimulated with the proinflammatory cytokine IL-1beta or tumor necrosis factor-alpha (TNF-alpha), and were received the irradiation of LED (632nm, 4mW/cm2). The cell count was assessed over a 96-hour period by using Trypan blue dye exclusion assay, and the cell activity was evaluated with a Cell Counting Kit-8 Assays. The subsequent expression of MMP-3 and MMP-13 was quantified. Results of this experiment showed that the cultural cell activity was decreased, and the expression of MMP-3 and MMP-13 was increased by being stimulated with IL-1beta or TNF-alpha. After received LED irradiation, the death rate of cultural cell was increased and the expression of MMP-3 and MMP-13 was decreased significantly. The present study concluded that particular LED irradiation stimulates SW1353 cell proliferation activity and inhibit the MMP-3 and MMP-13 enzymatic activity. These findings might be clinically relevant, indicating that the low power laser irradiation treatment is likely to achieve the repair of articular cartilage in clinic.

  9. Thymol and Thymus Vulgaris L. activity against UVA- and UVB-induced damage in NCTC 2544 cell line.

    Science.gov (United States)

    Calò, Rossella; Visone, Clementina M; Marabini, Laura

    2015-09-01

    Many authors focused on the research of natural compounds in order to protect skin from indirect (UVA) and direct (UVB) ultraviolet radiation side effects. The aim of this study to evaluate the protective effect of a dry extract from T. vulgaris L. and of its major synthetic compound thymol (about 60%), against oxidative and genotoxic UVA- and UVB damage. Experiments were reproduced in a low differentiated keratinocytes cell line (NCTC 2544) Cells were pretreated for 1h, in serum-free medium, with thymol (1μg/mL) or T. vulgaris L. (1.82μg/mL) then exposed to different UVA (8-24J/cm(2)) or UVB doses (0.016-0.72J/cm(2)). Immediately after the UV exposure the intracellular redox status was evaluated by ROS quantification and by LPO. Genotoxic aspects were evaluated 24h after the end of irradiations using the alkaline comet assay, the micronucleus formation assay and the immunostaining of phosphorylated H2AX histone protein (detected 1h after the end of UV exposure). Thymol and T. vulgaris L. extract inhibited ROS generation in UVA and UVB-irradiated cells. On the contrary, MDA formation was reduced only in UVA treated cells. Both agents decreased the DNA damage evaluated by the alkaline comet assay, but not in the micronucleus and H2AX tests probably because of the severity of damage (double strands) detected. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. An ascorbic acid-enriched tomato genotype to fight UVA-induced oxidative stress in normal human keratinocytes.

    Science.gov (United States)

    Petruk, Ganna; Raiola, Assunta; Del Giudice, Rita; Barone, Amalia; Frusciante, Luigi; Rigano, Maria Manuela; Monti, Daria Maria

    2016-10-01

    UVA radiations contribute up to 95% of the total UV exposure and are known to induce cell damage, leading to apoptosis. Since the benefic effects of ascorbic acid on human health are well known, a new tomato genotype (named DHO4), highly rich in ascorbic acid, has been recently obtained. Here, we compared the effects of ascorbic acid and hydrophilic DHO4 extracts in protecting human keratinocytes exposed to UVA stress. Keratinocytes were pre-incubated with ascorbic acid or with extracts from the ascorbic acid enriched tomato genotype and irradiated with UVA light. Then, ROS production, intracellular GSH and lipid peroxidation levels were quantified. Western blots were carried out to evaluate mitogen-activated protein kinases cascade, activation of caspase-3 and inflammation levels. We demonstrated that ROS, GSH and lipid peroxidation levels were not altered in cell exposed to UVA stress when cells were pre-treated with ascorbic acid or with tomato extracts. In addition, no evidence of apoptosis and inflammation were observed in irradiated pre-treated cells. Altogether, we demonstrated the ability of an ascorbic acid enriched tomato genotype to counteract UVA-oxidative stress on human keratinocytes. This protective effect is due to the high concentration of vitamin C that acts as free radical scavenger. This novel tomato genotype may be used as genetic material in breeding schemes to produce improved varieties with higher antioxidant levels. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Assessing the effects of UVA photocatalysis on soot-coated TiO2-containing mortars.

    Science.gov (United States)

    De la Rosa, José M; Miller, Ana Z; Pozo-Antonio, J Santiago; González-Pérez, José A; Jiménez-Morillo, Nicasio T; Dionisio, Amelia

    2017-12-15

    The deposition of soot on building surfaces darkens their colour and leads to undesirable black crusts, which are one of the most serious problems on the conservation of built cultural heritage. As a preventive strategy, self-cleaning systems based on the use of titanium dioxide (TiO2) coatings have been employed on building materials for degrading organic compounds deposited on building surfaces, improving their durability and performance. In this study, the self-cleaning effect of TiO2-containing mortars coated with diesel soot has been appraised under laboratory conditions. The mortar samples were manufactured using lime putty and two different doses of TiO2 (2.5% and 5%). The lime mortars were then coated with diesel engine soot and irradiated with ultraviolet A (UVA) illumination for 30days. The photocatalytic efficiency was evaluated by visual inspection, field emission scanning electron microscopy (FESEM) and colour spectrophotometry. Changes in the chemical composition of the soot particles (including persistent organic pollutants) were assessed by analytical pyrolysis (Py-GC/MS) and solid state 13C NMR spectroscopy. The FESEM and colour spectrophotometry revealed that the soot-coated TiO2-containing mortars promoted a self-cleaning effect after UVA irradiation. The combination of analytical pyrolysis and 13C solid state NMR showed that the UVA irradiation caused the cracking of polycyclic aromatic structures and n-alkyl compounds of the diesel soot and its transformation into methyl polymers. Our findings also revealed that the inclusion of TiO2 in the lime mortar formulations catalysed these transformations promoting the self-cleaning of the soot-stained mortars. The combined action of TiO2 and UVA irradiation is a promising proxy to clean lime mortars affected by soot deposition. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. In Vitro and In Vivo Radiosensitizing Effect of Valproic Acid on Fractionated Irradiation.

    Science.gov (United States)

    Chie, Eui Kyu; Shin, Jin Hee; Kim, Jin Ho; Kim, Hak Jae; Kim, In Ah; Kim, Il Han

    2015-07-01

    This study was conducted in order to validate the radiosensitization effect of valproic acid, a biologically available histone deacetylase inhibitor, for fractionated radiation. Radiosensitization effect of valproic acid was tested for the A549 cell line and U87MG cell line in vitro. Fractionated irradiation of 12 Gy in four fractions was administered on D2-5 with valproic acid, 150 mg/Kg, ip, bid for six consecutive days (D1-6) to A549 and U87MG tumors implanted in BALB/c-nude mice. A growth delay curve was formulated. Radiosensitization effect of valproic acid was found for both cell lines; A549 at 1.5 mM and 3.0 mM concentration and U87MG at 3.0 mM concentration. In growth delay analysis, a statistically significant radiosensitization effect was observed for both tumors (p < 0.001 for both tumors). Difference for change in slope for control and valproic acid versus radiotherapy and radiotherapy plus valproic acid showed borderline significance for the U87MG cell line (p=0.065), indicating beyond additive effect, whereas this difference was statistically insignificant for A549 tumor (p=0.951), indicating additive effect. Results of this study indicate that a radiosensitizing effect for fractionated radiotherapy of valproic acid for A549 and U87MG tumors in vivo is evident and that it may be more than additive for U87MG tumors. Further exploitation of histone deacetylase inhibitors in clinical trials is warranted.

  13. In Vitro Study of Er:YAG and Er, Cr:YSGG Laser Irradiation on Human Gingival Fibroblast Cell Line

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Talebi-Ardakani

    2016-05-01

    Full Text Available The ultimate goal of the periodontal treatments is a regeneration of periodontium. Recently, laser irradiations are commonly used to improve wound repair. Because of many controversies about the effects of laser on soft tissue regeneration, more in vitro studies are still needed. The aim of the present in vitro study was to compare the effects of different doses of Er:YAG (erbium-doped:yttrium, aluminum, garnet and Er, Cr:YSGG (erbium, chromium-doped: yttrium, scandium, gallium, garnet laser treatment on human gingival fibroblasts (HGF proliferation. In this randomized single-blind controlled in vitro trial, HGF cells were irradiated using Er:YAG and Er, Cr:YSGG laser for 10 and 30 seconds or remained unexposed as a control group. After a culture period of 24 and 48 hours, HGF cell proliferation was evaluated by MTT assay. The data were subjected to one-sided analysis of variance and Tukey multiple comparison tests. Our results showed Er:YAG application for 10 and 30 seconds as well as Er, Cr:YSGG irradiation for 10 and 30 seconds induced statistically significant (P<0.05 proliferation of HGF cells as compared with the control at 24 hours up to 18.39%, 26.22%, 21.21%, and 17.06% respectively. In 48 hour incubations, Er:YAG and Er, Cr:YSGG irradiation for 10 and 30 seconds significantly increased cellular proliferation up to 22.9%, 32.24%, 30.52% and 30.02% respectively (P<0.05. This study demonstrates that Er:YAG and Er, Cr:YSGG laser significantly increased HGF cell proliferation compared to the control specimens. This higher proliferation can lead to increased wound repair in clinical conditions.

  14. The bystander effect is a novel mechanism of UVA-induced melanogenesis.

    Science.gov (United States)

    Nishiura, Hideki; Kumagai, Jun; Kashino, Genro; Okada, Takuya; Tano, Keizo; Watanabe, Masami

    2012-01-01

    We successfully identified the bystander effect in B16 murine melanoma cells exposed to UVA irradiation. The effect was identified based on melanogenesis following the medium transfer of the B16 cells, which had been cultured for 24 h after being exposed to UVA irradiation, to nonirradiated cells (bystander cells). Our confirmation study of the functional mechanism of bystander cells confirmed the reduced levels of mitochondrial membrane potential 1-4 h after the medium transfer. In addition, we observed increased levels of intracellular oxidation after 9-12 h, and the generation of melanin radicals, including long-lived radicals, 24 h after medium transfer. Further analysis of bystander factors revealed that the administration of EGTA treatment at the time of medium transfer led to an inhibition of melanogenesis and to neutralization of the mitochondrial membrane potential level, as well as to the restoration of intracellular oxidation levels to those of controls. The results demonstrated that the UVA irradiation bystander effect in B16 cells, as indicated by melanogenesis, was induced by the increase in intracellular oxidation due to the mitochondrial activity of calcium ions, which were among the bystander factors involved in the increase. © 2011 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2011 The American Society of Photobiology.

  15. In vitro and in vivo characterization of ultraviolet light C-irradiated human platelets in a 2 event mouse model of transfusion.

    Directory of Open Access Journals (Sweden)

    Li Zhi

    Full Text Available UV-based pathogen reduction technologies have been developed in recent years to inactivate pathogens and contaminating leukocytes in platelet transfusion products in order to prevent transfusion-transmitted infections and alloimmunization. UVC-based technology differs from UVA or UVB-based technologies in that it uses a specific wavelength at 254 nm without the addition of any photosensitizers. Previously, it was reported that UVC irradiation induces platelet aggregation and activation. To understand if UVC-induced changes of platelet quality correlate with potential adverse events when these platelets are transfused into animals, we used a 2-event SCID mouse model in which the predisposing event was LPS treatment and the second event was infusion of UVC-irradiated platelets. We analyzed lung platelet accumulation, protein content in bronchoalveolar lavage fluid as an indication of lung injury, and macrophage inflammatory protein-2 (MIP-2 release in mice received UVC-irradiated or untreated control platelets. Our results showed UVC-irradiated platelets accumulated in lungs of the mice in a dose-dependent manner. High-doses of UVC-irradiated platelets were sequestered in the lungs to a similar level as we previously reported for UVB-irradiated platelets. Unlike UVB-platelets, UVC-platelets did not lead to lung injury or induce MIP-2 release. This could potentially be explained by our observation that although UVC treatment activated platelet surface αIIbβ3, it failed to activate platelet cells. It also suggests lung platelet accumulation and subsequent lung damage are due to different and separate mechanisms which require further investigation.

  16. MC1R expression in HaCaT keratinocytes inhibits UVA-induced ROS production via NADPH oxidase- and cAMP-dependent mechanisms.

    Science.gov (United States)

    Henri, Pauline; Beaumel, Sylvain; Guezennec, Anne; Poumès, Carine; Stoebner, Pierre-Emmanuel; Stasia, Marie-José; Guesnet, Joëlle; Martinez, Jean; Meunier, Laurent

    2012-06-01

    Ultraviolet A (UVA) radiations are responsible for deleterious effects, mainly due to reactive oxygen species (ROS) production. Alpha-melanocyte stimulating hormone (α-MSH) binds to melanocortin-1 receptor (MC1R) in melanocytes to stimulate pigmentation and modulate cutaneous inflammatory responses. MC1R may be induced in keratinocytes after UV exposure. To investigate the effect of MC1R signaling on UVA-induced ROS (UVA-ROS) production, we generated HaCaT cells that stably express human MC1R (HaCaT-MC1R) or the Arg151Cys (R(151)C) non-functional variant (HaCaT-R(151)C). We then assessed ROS production immediately after UVA exposure and found that: (1) UVA-ROS production was strongly reduced in HaCaT-MC1R but not in HaCaT-R(151)C cells compared to parental HaCaT cells; (2) this inhibitory effect was further amplified by incubation of HaCaT-MC1R cells with α-MSH before UVA exposure; (3) protein kinase A (PKA)-dependent NoxA1 phosphorylation was increased in HaCaT-MC1R compared to HaCaT and HaCaT-R(151)C cells. Inhibition of PKA in HaCaT-MC1R cells resulted in a marked increase of ROS production after UVA irradiation; (4) the ability of HaCaT-MC1R cells to produce UVA-ROS was restored by inhibiting epidermal growth factor receptor (EGFR) or extracellular signal-regulated kinases (ERK) activity before UVA exposure. Our findings suggest that constitutive activity of MC1R in keratinocytes may reduce UVA-induced oxidative stress via EGFR and cAMP-dependent mechanisms. Copyright © 2011 Wiley Periodicals, Inc.

  17. Effects of carbon ion beam irradiation on the shoot regeneration from in vitro axillary bud explants of the Impatiens hawkeri

    Science.gov (United States)

    Zhou, Libin; Zhou, Libin; Li, Wenjian; Li, Ping; Dong, Xicun; Qu, Ying; Ma, Shuang; Li, Qiang

    Accelerated ion beams is an excellent mutagen in plant breeding which can induce higher mutation frequencies and wider mutation spectrum than those of low linear energy transfer (LET) irradiations, such as X-rays (Okamura et al. 2003, Yamaguchi et al. 2003). Mutation breeding operation of two Saintpaulia ionahta cultivars using the method combining plant tissue culture technique and carbon ion beam irradiations were set out at Institute of Modern Physics from 2005 (Zhou et al. 2006). The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiations on regenerated shoots of Impatiens hawkeri from another kind of explants named in vitro axillary buds explants were studied recently. The biology endpoints in this study included relative number of roots (RNR), relative length of roots (RLR), relative height of shoots (RHS), relative number of nodes (RNN), survival fraction (SF) and morphology changes in the regenerated shoots. The experimental results showed that carbon ion beams inhibited the root and stem developments of axillary bud explants more severely than X-rays did. And the 50% lethal dose (LD50 ) is about 23.3 Gy for the carbon ion beam and 49.1 Gy for the X-rays, respectively. Relative biological effectiveness (RBE) of Impatiens hawkeri with respect to X-rays according to 50% SF was about two. Secondly, the percentage of shoots regenerated with malformed shoots including curliness, carnification, nicks in all Impatiens hawkeri axillary bud explants irradiated with carbon ion beam at 20 Gy accounted for 55.6%, while the highest number for the 40 Gy X-ray irradiation was 40%. Last, many regenerated shoots whose vascular bundle fused together were obtained only from explants irradiated with carbon ion beams. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the axillary explants of Impatiens hawkeri is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy

  18. Photoprotective Effects of Cycloheterophyllin against UVA-Induced Damage and Oxidative Stress in Human Dermal Fibroblasts.

    Directory of Open Access Journals (Sweden)

    Cheng-Hua Huang

    Full Text Available Ultraviolet (UV radiation, particularly ultraviolet A (UVA, is known to play a major role in photoaging of the human skin. Many studies have demonstrated that UV exposure causes the skin cells to generate reactive oxygen species and activates the mitogen-activated protein kinase (MAPK pathway. Previous studies have also demonstrated that cycloheterophyllin has an antioxidant effect and can effectively scavenge free radicals. Extending the aforementioned investigations, in this study, human dermal fibroblasts were used to investigate the protective effect of cycloheterophyllin against UV-induced damage. We found that cycloheterophyllin not only significantly increased cell viability, but also attenuated the phosphorylation of MAPK after UVA exposure. Furthermore, cycloheterophyllin could reduce hydrogen peroxide (H2O2 generation and down-regulate H2O2-induced MAPK phosphorylation. In the in vivo studies, the topical application of cycloheterophyllin before UVA irradiation significantly decreased trans-epidermal water loss (TEWL, erythema, and blood flow rate. These results indicate that cycloheterophyllin is a photoprotective agent that inhibits UVA-induced oxidative stress and damage, and could be used in the research on and prevention of skin photoaging.

  19. Strawberry-Based Cosmetic Formulations Protect Human Dermal Fibroblasts against UVA-Induced Damage

    Directory of Open Access Journals (Sweden)

    Massimiliano Gasparrini

    2017-06-01

    Full Text Available Extreme exposure of skin to Ultraviolet A (UVA-radiation may induce a dysregulated production of reactive oxygen species (ROS which can interact with cellular biomolecules leading to oxidative stress, inflammation, DNA damage, and alteration of cellular molecular pathways, responsible for skin photoaging, hyperplasia, erythema, and cancer. For these reasons, the use of dietary natural bioactive compounds with remarkable antioxidant activity could be a strategic tool to counteract these UVA-radiation-caused deleterious effects. Thus, the purpose of the present work was to test the efficacy of strawberry (50 μg/mL-based formulations supplemented with Coenzyme Q10 (100 μg/mL and sun protection factor 10 in human dermal fibroblasts irradiated with UVA-radiation. The apoptosis rate, the amount of intracellular reactive oxygen species (ROS production, the expression of proteins involved in antioxidant and inflammatory response, and mitochondrial functionality were evaluated. The results showed that the synergic topical use of strawberry and Coenzyme Q10 provided a significant (p < 0.05 photoprotective effect, reducing cell death and ROS, increasing antioxidant defense, lowering inflammatory markers, and improving mitochondrial functionality. The obtained results suggest the use of strawberry-based formulations as an innovative, natural, and useful tool for the prevention of UVA exposure-induced skin diseases in order to decrease or substitute the amount of synthetic sunscreen agents.

  20. Strawberry-Based Cosmetic Formulations Protect Human Dermal Fibroblasts against UVA-Induced Damage.

    Science.gov (United States)

    Gasparrini, Massimiliano; Forbes-Hernandez, Tamara Y; Afrin, Sadia; Reboredo-Rodriguez, Patricia; Cianciosi, Danila; Mezzetti, Bruno; Quiles, Josè L; Bompadre, Stefano; Battino, Maurizio; Giampieri, Francesca

    2017-06-14

    Extreme exposure of skin to Ultraviolet A (UVA)-radiation may induce a dysregulated production of reactive oxygen species (ROS) which can interact with cellular biomolecules leading to oxidative stress, inflammation, DNA damage, and alteration of cellular molecular pathways, responsible for skin photoaging, hyperplasia, erythema, and cancer. For these reasons, the use of dietary natural bioactive compounds with remarkable antioxidant activity could be a strategic tool to counteract these UVA-radiation-caused deleterious effects. Thus, the purpose of the present work was to test the efficacy of strawberry (50 μg/mL)-based formulations supplemented with Coenzyme Q10 (100 μg/mL) and sun protection factor 10 in human dermal fibroblasts irradiated with UVA-radiation. The apoptosis rate, the amount of intracellular reactive oxygen species (ROS) production, the expression of proteins involved in antioxidant and inflammatory response, and mitochondrial functionality were evaluated. The results showed that the synergic topical use of strawberry and Coenzyme Q10 provided a significant (p defense, lowering inflammatory markers, and improving mitochondrial functionality. The obtained results suggest the use of strawberry-based formulations as an innovative, natural, and useful tool for the prevention of UVA exposure-induced skin diseases in order to decrease or substitute the amount of synthetic sunscreen agents.

  1. Antimicrobial effects of phototherapy and photochemotherapy in vivo and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimura, M.; Namura, S.; Akamatsu, H.; Horio, T. [Kansai Medical Univ., Moriguchi, Osaka (Japan). Dept. of Dermatology

    1996-10-01

    We investigated the antimicrobial effects of phototherapy and photochemotherapy in vivo and in vitro. First, Staphylococcus aureus samples were obtained using stamp agar medium from inflammatory lesions of 29 adult patients with atopic dermatitis before and after a single photochemotherapy. Therapy was oral PUVA (30 mg 8-methoxypsoralen, 8MOP plus 5 J/cm{sup 2}UVA), topical PUVA (0.3% 8MOP plus 200 mJ/cm{sup 2}UVA) or UVB (80 mJ/cm{sup 2}) irradiation. The number of S. aureus on the lesions was significantly reduced, even after a single treatment with all therapies. Reductions (mean {+-} SD) were 69.3 {+-} 26.9%, 76.3 {+-} 31.3% and 83.8 {+-} 18.5%, respectively. Secondly, we investigated the effect of PUVA (0.001% 8MOP plus 10, 20, 30, 40, or 50 mJ/cm{sup 2} UVA) and UVB (10, 30, 50, or 100 mJ/cm{sup 2}) irradiation on the proliferation of S. aureus in vitro. PUVA and UVB treatment markedly inhibited the proliferation in a dose-dependent manner. These results seem to indicate the possibility that the antimicrobial effect of UV radiation contributes to successful photochemotherapy in patients with atopic dermatitis. (Author).

  2. UVA, pheomelanin and the carcinogenesis of melanoma.

    Science.gov (United States)

    Hill, H Z; Hill, G J

    2000-01-01

    Cloudman S91 mouse melanoma cells vary in constitutive and inducible melanin levels. Survival, mutation induction and DNA damage were quantitated after exposure to UVB, UVA and FS20 lamps. Assuming that the observed differences are related to melanin, induced pigment is photo-protective for survival and mutation after UVB and FS20 exposure, and is photosensitizing for survival after UVA exposure. No changes in pyrimidine dimers could be measured. DNA damage in pigmented mouse melanocytes (melan-a and melan-b) was greater than that in albino melanocytes (melan-c) after UVB and FS20, and the pigmented cells were more sensitive to killing. Pigment appears to be protective for killing by UVA in these melanocytes. Human melanocytes from different skin types vary in both melanin amount and composition (eu- and pheomelanin). Effects of pigmentation on UVB responses are unclear. In UVA, heavily pigmented cells have more DNA damage than lightly pigmented cells, but are resistant to killing. Increased pheomelanin photosensitizes DNA damage in lightly pigmented cells. Since eumelanin predominates in the mouse melanoma cells and melanocytes, they are less likely than human cells to provide a satisfactory model for human solar melanomagenesis. In order to understand the mechanism of photocarcinogenesis of melanoma, melanins in human melanocytes from different pigment types should be carefully quantitated and characterized. Mutations induced in them by solar wavelength-emitting lamps with well-characterized spectra should be measured, and mutant DNA should be sequenced to determine the nature of the solar-induced lesions. Research should focus on UVA and pheomelanin.

  3. Chemiluminescence response of human neutrophils to He-Ne laser irradiation (in vivo and in vitro)

    OpenAIRE

    Schepetkin, I.; Udut, V.; Karpov, A.

    1994-01-01

    He-Ne laser irradiation (0.01-6 J/cm3) of the blood and neutrophile suspension in vitrowas shown to modulate reactive oxygen species (ROS) production in healthy donors. Intravascular laser irradiation of the blood (5 mW, 30 minutes, daily) of the patients with chronic gastric ulcer during first 5 days resulted in increasing stimul-induced ROS production in patients with the low initial chemiluminescence response and its decreasing in patients with the high initial chemiluminescence response.

  4. Safety Irradiation Parameters of Nd:YAP Laser Beam for Endodontic Treatments: An In Vitro Study.

    Science.gov (United States)

    Namour, A; Geerts, S; Zeinoun, T; De Moor, R; Nammour, S

    2016-01-01

    Objective. Nd:YAP laser has several potentialities of clinical applications in endodontics. The aim of our study is to determine the safety range of irradiation parameters during endodontic application of Nd:YAP laser that can be used without damaging and overheating the periodontal tissue. Material and Methods. Twenty-seven caries-free single-rooted extracted human teeth were used. Crowns were sectioned to obtain 11 mm root canal length. Temperature increases at root surfaces were measured by a thermocouple during Nd:YAP laser irradiation of root canals at different energy densities. Canal irradiation was accomplished with a circular and retrograde movement from the apex until the cervical part of the canal during 10 seconds with an axial speed of 1 mm/s. Each irradiation was done in a canal irrigated continuously with 2.25% NaOCl solution. Results. Periodontal temperature increase depends on the value of energy density. Means and standard deviations of temperature increases at root surfaces were below 10°C (safe threshold level) when the average energy densities delivered per second were equal to or below 4981 J/cm(2) and 9554 J/cm(2), respectively, for irradiations using a fiber diameter of 320 μm and 200 μm. Conclusions. Within the limitations of this study and under specific irradiation conditions, Nd:YAP laser beam may be considered harmless for periodontal tissues during endodontic applications.

  5. Safety Irradiation Parameters of Nd:YAP Laser Beam for Endodontic Treatments: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    A. Namour

    2016-01-01

    Full Text Available Objective. Nd:YAP laser has several potentialities of clinical applications in endodontics. The aim of our study is to determine the safety range of irradiation parameters during endodontic application of Nd:YAP laser that can be used without damaging and overheating the periodontal tissue. Material and Methods. Twenty-seven caries-free single-rooted extracted human teeth were used. Crowns were sectioned to obtain 11 mm root canal length. Temperature increases at root surfaces were measured by a thermocouple during Nd:YAP laser irradiation of root canals at different energy densities. Canal irradiation was accomplished with a circular and retrograde movement from the apex until the cervical part of the canal during 10 seconds with an axial speed of 1 mm/s. Each irradiation was done in a canal irrigated continuously with 2.25% NaOCl solution. Results. Periodontal temperature increase depends on the value of energy density. Means and standard deviations of temperature increases at root surfaces were below 10°C (safe threshold level when the average energy densities delivered per second were equal to or below 4981 J/cm2 and 9554 J/cm2, respectively, for irradiations using a fiber diameter of 320 μm and 200 μm. Conclusions. Within the limitations of this study and under specific irradiation conditions, Nd:YAP laser beam may be considered harmless for periodontal tissues during endodontic applications.

  6. Distinctive Genomic Profiles of Normal and Transformed Thyrocytes Irradiated with Low vs. High Doses of X-irradiation both in vivo and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Abou-El-Ardat, K. [Radiobiology, SCK-CEN, Mol (Belgium); Molecular Biotechnology, Universiteit Gent, Ghent (Belgium); Monsieurs, P. [Microbiology, SCK-CEN, Mol (Belgium); Janssen, A.; Beck, M; Michaux, A.; Benotmane, R.; Derradji, H.; Baatout, S. [Radiobiology, SCK-CEN, Mol (Belgium); Anastasov, N.; Atkinson, M. [Radiology, Helmholtz Zentrum Munchen, Munich (Germany); Beckaert, S.; Van Criekinge, W. [Molecular Biotechnology, Universiteit Gent, Ghent (Belgium)

    2012-07-01

    The increase in cases of papillary thyroid carcinoma (PTC) in the aftermath of the Chernobyl disaster led to an elevation of interest in the effect of radiation on the thyroid. Our work hopes to uncover some of the effects of low doses of external X-radiation in in vitro and in vivo models using several techniques and robust analysis. Here we describe the use of such models combined with micro-arrays and sound statistical analysis. we find that low doses of radiation act differently on murine thyroids carrying and lacking the RET/PTC translocation and even bear a distinctive profile to higher irradiation doses in both in vitro and in vivo models. We also find that micro-RNAs are involved in the response of these cells to radiation, even at low doses and that two in particular, let-7g and miR-106a, were significantly involved in the cells' p53-mediated anti-proliferative response

  7. Wound healing in the rabbit cornea after corneal collagen cross-linking with riboflavin and UVA.

    Science.gov (United States)

    Wollensak, Gregor; Iomdina, Elena; Dittert, Dag-Daniel; Herbst, Hermann

    2007-06-01

    This study was undertaken to investigate the wound healing process of the first 6 weeks after photodynamic cross-linking treatment in the rabbit cornea, using the photosensitizer riboflavin and UVA. After removal of the central epithelium, the right corneas of 8 Chinchilla rabbits were cross-linked with a photosensitizing 0.1% riboflavin solution and UVA light (370 nm; irradiance, 3 mW/cm(2); dose, 5.4 J/cm(2)) for 30 minutes. Two animals were euthanized 3 days, 7 days, 4 weeks, and 6 weeks postoperatively. The corneas of the enucleated eyes were evaluated using 4-microm light microscopic sections with routine stains and avidin-biotin complex immunostaining with anti-alpha-smooth muscle actin. By day 3 after treatment, complete apoptotic damage and loss of the endothelial cells and the stromal keratocytes were found in the irradiated area through the entire thickness of the stroma. There was marked stromal edema (850 +/- 66 vs. 332 +/- 43 microm in the untreated controls; P neutrophils. By day 7, the endothelium was already intact again, and keratocyte repopulation of the posterior stroma was noted. By week 4, the keratocyte repopulation of the anterior stroma was observed with some acellular areas between. By week 6, the cytoarchitecture of the cornea seemed normal again. By weeks 4 and 6, alpha-actin-positive keratocytes were identified, especially in the periphery of the irradiated area. After riboflavin/UVA cross-linking of rabbit cornea, a complete cell loss occurs in the irradiation area with an irradiance of 3 mW/cm(2). The cytotoxic damage is repaired by repopulation after approximately 4-6 weeks. A combination of cross-linking with other procedures such as the implantation of intracorneal rings should be performed only after a sufficient time interval of approximately 2 months, allowing cellular regeneration.

  8. Solar radiation (PAR, UV-A, UV-B) penetration in a shallow maturation pond operating in a tropical climate.

    Science.gov (United States)

    Dias, Daniel F C; von Sperling, Marcos

    2017-07-01

    Solar radiation is considered the primary route for disinfection of pathogenic bacteria in maturation ponds. There is scarce information on depth profiling and attenuation of photosynthetically active radiation (PAR), UV-A and UV-B in shallow maturation ponds operating in tropical climates. Measurements of solar irradiance of the three wavelength ranges, together with turbidity, have been acquired from different depths for over 1 year in a shallow maturation pond (44 cm of depth) operating in Brazil. UV-A and UV-B were still detected at 10 cm from the surface, but from 15 cm both were undetectable. PAR was still detected at 30 cm of depth. Irradiation attenuation showed to be related to turbidity. Attenuation coefficients were calculated and simple models without turbidity (traditional structure) or including log 10 of turbidity are proposed for predicting PAR irradiance attenuation as a function of depth.

  9. Considering the antibacterial activity of Zataria multiflora Boiss essential oil treated with gamma-irradiation in vitro and in vivo systems

    Science.gov (United States)

    Faezeh, Fatema; Salome, Dini; Abolfazl, Dadkhah; Reza, Zolfaghari Mohammad

    2015-01-01

    The aim of the present study was to evaluate the antibacterial activities of essential oils (EOs) obtained from the aerial parts of Zataria multiflora Boiss against Bacillus cereus, Pseudomonas aeroginosa, Escherichia coli and Staphylococcus aureus by in vivo and in vitro methods. Also, the effects of gamma-irradiation (0, 10 and 25 kGy) as a new microbial decontamination on the antibacterial activities of Z. multiflora were examined. For this purpose, the collected herbs were exposed to radiation at doses of 0, 10 and 25 kGy following essential oil (EOs) extraction by steam distillation. Then, the in vitro antibacterial potency of the irradiated and non-irradiated oils was determined by using disc diffusion, agar well diffusion and MIC and MBC determination assays. The in vivo antibacterial activity was also studied in sepsis model induced by CLP surgery by Colony forming units (CFUs) determination. The results showed that the extracted oils were discovered to be effective against all the gram positive and gram negative pathogens in vitro system. In addition, the oil significantly diminished the increased CFU count observed in CLP group. Moreover, the irradiated samples were found to possess the antibacterial activities as the non-irradiated ones both in vitro and in vivo systems. These data indicated the potential use of gamma-irradiation as a safe technique for preservation of Z. multiflora as a medicinal plant with effective antibacterial activities.

  10. Response and Defense Mechanisms of Taxus chinensis Leaves Under UV-A Radiation are Revealed Using Comparative Proteomics and Metabolomics Analyses.

    Science.gov (United States)

    Zheng, Wen; Komatsu, Setsuko; Zhu, Wei; Zhang, Lin; Li, Ximin; Cui, Lei; Tian, Jingkui

    2016-09-01

    Taxus chinensis var. mairei is a species endemic to south-eastern China and one of the natural sources for the anticancer medicine paclitaxel. To investigate the molecular response and defense mechanisms of T. chinensis leaves to enhanced ultraviolet-A (UV-A) radiation, gel-free/label-free and gel-based proteomics and gas chromatography-mass spectrometry (GC-MS) analyses were performed. The transmission electron microscopy results indicated damage to the chloroplast under UV-A radiation. Proteomics analyses in leaves and chloroplasts showed that photosynthesis-, glycolysis-, secondary metabolism-, stress-, and protein synthesis-, degradation- and activation-related systems were mainly changed under UV-A radiation. Forty-seven PSII proteins and six PSI proteins were identified as being changed in leaves and chloroplasts under UV-A treatment. This indicated that PSII was more sensitive to UV-A than PSI as the target of UV-A light. Enhanced glycolysis, with four glycolysis-related key enzymes increased, provided precursors for secondary metabolism. The 1-deoxy-d-xylulose-5-phosphate reductoisomerase and 4-hydroxy-3-methylbut-2-enyl diphosphate reductase were identified as being significantly increased during UV-A radiation, which resulted in paclitaxel enhancement. Additionally, mRNA expression levels of genes involved in the paclitaxel biosynthetic pathway indicated a down-regulation under UV-A irradiation and up-regulation in dark incubation. These results reveal that a short-term high dose of UV-A radiation could stimulate the plant stress defense system and paclitaxel production. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  11. Prevention of polymorphic light eruption with a sunscreen of very high protection level against UVB and UVA radiation under standardized photodiagnostic conditions.

    Science.gov (United States)

    Schleyer, Verena; Weber, Oliver; Yazdi, Amir; Benedix, Frauke; Dietz, Klaus; Röcken, Martin; Berneburg, Mark

    2008-01-01

    Polymorphic light eruption (PLE), with an overall prevalence of 10-20%, is mainly provoked by ultraviolet A (UVA) (320-400 nm) and to a lesser degree by UVB (280-320 nm). The most effective prophylaxis of PLE, application of UV protection clothing, is not feasible for all sun-exposed areas of the skin and UV-hardening is time-consuming and may be associated with side-effects. Most sunscreens protect predominantly against UVB and therefore fail to prevent PLE. The protection level of potent UVA-protective filters remains unresolved. This single-centre, open, placebo-controlled, intra-individual, comparative study, analysed the efficacy of a sunscreen of very high protection level against UVB and UVA, containing methylene bis-benzotriazolyl tetramethylbutylphenol (Tinosorb M), bis-ethylhexyloxyphenol methoxyphenyl triazine (Tinosorb S) and butyl methoxydibenzoylmethane as UVA absorbing filters, in the prevention of PLE under standardized photodiagnostic conditions. After determination of the minimal erythema dose at day 0, photoprovocation was performed in 12 patients with a clinical history of PLE, on days 1, 2 and 3 with 100 J/cm2 UVA and variable doses of UVB, starting with the 1.5-fold minimal erythema dose of UVB. Prior to irradiation, placebo was applied to the right and sunscreen to the left dorsal forearm under COLIPA (European Cosmetic, Toiletry and Perfumery Association) conditions. In 10 patients PLE could be provoked at the placebo site, with positive reactions in 90% of the UVA, 40% of the UVB and 90% of the UVA/UVB irradiated fields. At the site with the active treatment none of these patients developed PLE. These data demonstrate that a sunscreen with effective filters against UVA and UVB can successfully prevent the development of PLE. Further studies are needed to examine whether regular application of sunscreen under everyday conditions, especially in doses less than the tested COLIPA-norm, could be an equivalent alternative to UV-hardening therapy.

  12. Identification of irradiated food. I.- A test established on the in vitro culture of potato buds to identified the irradiated tubers; Identificacion de alimentos irradiados. I. Test basado en el cultivo de yemas in vitro para la identificacion de tuberculos de patatas irradiada

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Gonzalez, J.; Garcia Collantes, M. A.

    1976-07-01

    A method based upon the in vitro culture of potato buds in a mineral medium is described, by which method tubers irradiated can be distinguished from tubers treated by refrigeration or inhibited by chemical agents. (Author) 9 refs.

  13. Investigation of the bystander effect in MRC5 cells after acute and fractionated irradiation in vitro

    Directory of Open Access Journals (Sweden)

    Shokouhozaman Soleymanifard

    2014-01-01

    Full Text Available Radiation-induced bystander effect (RIBE has been defined as radiation responses observed in nonirradiated cells. It has been the focus of investigators worldwide due to the deleterious effects it induces in nonirradiated cells. The present study was performed to investigate whether acute or fractionated irradiation will evoke a differential bystander response in MRC5 cells. A normal human cell line (MRC5, and a human lung tumor cell line (QU-DB were exposed to 0, 1, 2, and 4Gy of single acute or fractionated irradiation of equal fractions with a gap of 6 h. The MRC5 cells were supplemented with the media of irradiated cells and their micronucleus frequency was determined. The micronucleus frequency after single and fractionated irradiation did not vary significantly in the MRC5 cells conditioned with autologous or QU-DB cell-irradiated media, except for 4Gy where the frequency of micronucleated cells was lower in those MRC5 cells cultured in the media of QU-DB-exposed with a single dose of 4Gy. Our study demonstrates that the radiation-induced bystander effect was almost similar after single acute and fractionated exposure in MRC5 cells.

  14. Investigation of the bystander effect in MRC5 cells after acute and fractionated irradiation in vitro.

    Science.gov (United States)

    Soleymanifard, Shokouhozaman; Toossi, Mohammad Taghi Bahreyni; Samani, Roghayeh Kamran; Mohebbi, Shokoufeh

    2014-04-01

    Radiation-induced bystander effect (RIBE) has been defined as radiation responses observed in nonirradiated cells. It has been the focus of investigators worldwide due to the deleterious effects it induces in nonirradiated cells. The present study was performed to investigate whether acute or fractionated irradiation will evoke a differential bystander response in MRC5 cells. A normal human cell line (MRC5), and a human lung tumor cell line (QU-DB) were exposed to 0, 1, 2, and 4Gy of single acute or fractionated irradiation of equal fractions with a gap of 6 h. The MRC5 cells were supplemented with the media of irradiated cells and their micronucleus frequency was determined. The micronucleus frequency after single and fractionated irradiation did not vary significantly in the MRC5 cells conditioned with autologous or QU-DB cell-irradiated media, except for 4Gy where the frequency of micronucleated cells was lower in those MRC5 cells cultured in the media of QU-DB-exposed with a single dose of 4Gy. Our study demonstrates that the radiation-induced bystander effect was almost similar after single acute and fractionated exposure in MRC5 cells.

  15. Management of Root Perforations Using MTA with or without Er:YAG Laser Irradiation: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    M. Tielemans

    2012-01-01

    Full Text Available The aim of this in vitro study is to compare the microleakage of a root perforation sealed with MTA (mineral trioxide aggregate (group M to that sealed with MTA following Er:YAG laser irradiation (group ML. Forty-two recently extracted human monoroot teeth were used. Two cavities were prepared on each root surface. Randomly, on each root, the exposed dentine of one cavity was irradiated prior to MTA filling using an Er:YAG laser with the following settings: 200 mJ/pulses under an air water spray, 10 Hz, pulse duration of 50 μsec, and 0.7 mm beam diameter. All cavities were then sealed with MTA. submitted to thermocycling and immersed in 2% methylene blue dye solution for 12 h. The penetration of methylene blue in the microleakage of cavity was observed and recorded. The mean value dye penetration in cavities sealed with MTA following Er:YAG laser irradiation (23.91±14.63% was lower than that of unlased cavities sealed only with MTA (25.17±17.53%. No significant difference was noted. The use of an Er:YAG laser beam for dentinal conditioning prior to MTA filling of perforated roots did not decrease significantly the microleakage of MTA sealing when compared to the conventional use of MTA filling.

  16. The effects of lipid A on gamma-irradiated human peripheral blood lymphocytes in vitro

    Science.gov (United States)

    Dubničková, M.; Kuzmina, E. A.; Chausov, V. N.; Ravnachka, I.; Boreyko, A. V.; Krasavin, E. A.

    2016-03-01

    The modulatory effects of lipid A (diphosphoryl lipid A (DLA) and monophosphoryl lipid A (MLA)) on apoptosis induction and DNA structure damage (single and double-strand breaks (SSBs and DSBs, respectively)) in peripheral human blood lymphocytes are studied for 60Co gamma-irradiation. It is shown that in the presence of these agents the amount of apoptotic cells increases compared with the irradiated control samples. The effect is most strongly pronounced for DLA. In its presence, a significant increase is observed in the number of radiation-induced DNA SSBs and DSBs. Possible mechanisms are discussed of the modifying influence of the used agents on radiation-induced cell reactions

  17. Protective effect of Vaccinium myrtillus extract against UVA- and UVB-induced damage in a human keratinocyte cell line (HaCaT cells).

    Science.gov (United States)

    Calò, Rossella; Marabini, Laura

    2014-03-05

    Recently, the field of skin protection have shown a considerable interest in the use of botanicals. Vaccinium myrtillus contains several polyphenols and anthocyanins with multiple pharmacological properties. The purpose of our study was to examine whether a water-soluble V. myrtillus extract (dry matter 12.4%; total polyphenols 339.3mg/100 g fw; total anthocyanins 297.4 mg/100 g fw) was able to reduce UVA- and UVB-induced damage using a human keratinocyte cell line (HaCaT). HaCaT cells were pretreated for 1h with extract in a serum-free medium and then irradiated with UVA (8-40 J/cm(2)) and UVB (0.008-0.72 J/cm(2)) rays. All experiments were performed 24h after the end of irradiation, except for oxidative stress tests. The extract was able to reduce the UVB-induced cytotoxicity and genotoxicity (studied by comet and micronucleous assays) at lower doses. V. myrtillus extract reduced lipid peroxidation UVB-induced, but had no effect against the ROS UVB-produced. With UVA-induced damage V. myrtillus reduced genotoxicity as well as the unbalance of redox intracellular status. Moreover our extract reduced the UVA-induced apoptosis, but had no effect against the UVB one. V. myrtillus extract showed its free radical scavenging properties reducing oxidative stress and apoptotic markers, especially in UVA-irradiated cells. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Low-level laser irradiation induces in vitro proliferation of mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Barboza, Carlos Augusto Galvão; Ginani, Fernanda [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil); Soares, Diego Moura [Universidade Federal de Pernambuco, Recife, PE (Brazil); Henriques, Águida Cristina Gomes; Freitas, Roseana de Almeida [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil)

    2014-07-01

    To evaluate the effect of low-level laser irradiation on the proliferation and possible nuclear morphological changes of mouse mesenchymal stem cells. Mesenchymal stem cells derived from bone marrow and adipose tissue were submitted to two applications (T0 and T48 hours) of low-level laser irradiation (660nm; doses of 0.5 and 1.0J/cm{sup 2}). The trypan blue assay was used to evaluate cell viability, and growth curves were used to analyze proliferation at zero, 24, 48, and 72 hours. Nuclear alterations were evaluated by staining with DAPI (4'-6-diamidino-2-phenylindole) at 72 hours. Bone marrow-derived mesenchymal stem cells responded to laser therapy in a dose-dependent manner. Higher cell growth was observed when the cells were irradiated with a dose of 1.0J/cm{sup 2}, especially after 24 hours (p<0.01). Adipose-derived mesenchymal stem cells responded better to a dose of 1.0J/cm{sup 2}, but higher cell proliferation was observed after 48 hours (p<0.05) and 72 hours (p<0.01). Neither nuclear alterations nor a significant change in cell viability was detected in the studied groups. Low-level laser irradiation stimulated the proliferation of mouse mesenchymal stem cells without causing nuclear alterations. The biostimulation of mesenchymal stem cells using laser therapy might be an important tool for regenerative therapy and tissue engineering.

  19. Photoproducts in DNA irradiated In vitro and In vivo under extreme environmental conditions

    Science.gov (United States)

    Riklis, Emanuel

    UV-irradiated DNA forms different photoproducts in accordance with its state of hydration, and the environment in which the irradiation takes place. Photoproducts in addition to the well-known thymine dimer are produced, some of which probably not recognized due to being heat or acid labile, and milder methods for DNA hydrolysis are needed. The isolation, structure and properties of photoproducts which are formed in UV-irradiated frozen thymine solutions are described. Urea, n-propylurea and dihydrothymine are obtained as photolytic products by high radiation doses in low concentrations of thymine. The cyclobutane cis-anti thymine dimer is obtained at high concentrations of thymine, following several cycles of freezing, thawing and irradiations. A trimer is obtained with 290 nm UV light filtered through Pyrex. It reverts back to thymine dimer and thymine when reirradiated in solution. The cis-syn dimer is obtained at all concentrations of frozen thymine and in a dose dependent form. The adduct 5-hydroxy-6-4' (5'- methylpyrimid 2'-1) dihydrothymine is also obtained. In vacuum-dried thymine or DNA, other photoproducts are formed, including the spore-product, TDHT. Several solvent systems were used to develop chromatograms that allow seperation of photoproducts.

  20. Enhancing antioxidant activity, microbial and sensory quality of mango (Mangifera indica L.) juice by γ-irradiation and its in vitro radioprotective potential.

    Science.gov (United States)

    Naresh, Kondapalli; Varakumar, Sadineni; Variyar, Prasad Shekhar; Sharma, Arun; Reddy, Obulam Vijaya Sarathi

    2015-07-01

    Gamma irradiation is an effective method currently being used for microbial decontamination and insect disinfestations of foods. In the present study, mango (Mangifera indica L.) juice was irradiated at doses of 0, 1.0, 3.0 and 5.0 kGy and microbial load, total polyphenols, flavonoids, ascorbic acid content, antioxidant activities, colour and sensory properties were evaluated immediately after irradiation and also during storage. Microbiological assay of the fresh and stored mango juice showed better quality after γ-irradiation. The total polyphenols and flavonoids were significantly (p mango juice without any adverse changes in the sensory qualities. Significant in vitro plasmid DNA protection was observed in the presence of mango juice against radiation induced damage, even at the dose of 5 kGy. This study confirmed the potential of γ-irradiation as a method for microbial decontamination and improving the quality of the mango juice without compromising on the sensory attributes.

  1. Low-power laser irradiation inhibits arecoline-induced fibrosis: an in vitro study

    OpenAIRE

    Yeh, Mei-Chun; Chen, Ker-Kong; Chiang, Min-Hsuan; Chen, Chia-Hsin; Chen, Ping-Ho; Lee, Huey-Er; Wang, Yan-Hsiung

    2017-01-01

    Oral submucous fibrosis (OSF) is a potentially malignant disorder that is characterized by a progressive fibrosis in the oral submucosa. Arecoline, an alkaloid compound of the areca nut, is reported to be a major aetiological factor in the development of OSF. Low-power laser irradiation (LPLI) has been reported to be beneficial in fibrosis prevention in different damaged organs. The aim of this study was to investigate the potential therapeutic effects of LPLI on arecoline-induced fibrosis. A...

  2. Effects of He-Ne laser irradiation on red blood cells in vitro

    Science.gov (United States)

    Ghadage, Vijay H.; Kulkarni, Gauri R.

    2011-03-01

    Laser radiation has many applications in biomedical field, such as wound healing, tissue repairing, heating and ablation processes. Intravenous low power laser radiation is used clinically for skin and vascular disorders. Laser radiation improves microcirculation and modulates the rheological properties of blood. FTIR (Fourier Transform Infra Red Spectra) is used to see the structural changes in erythrocyte membrane. In the present work He Ne laser (λ= 632nm, power=2mW) is used to irradiate human Red blood cells. Red blood cells are separated from human whole blood using centrifugation method (time=10 min., temperature=15°C and RPM=3000) and then exposed to HeNe laser radiation. Laser exposure time is varied from 10 min. to 40min for Red blood cells. Absorption spectrum, FTIR and fluorescence spectra of RBC are compared before and after HeNe laser irradiation. The absorption spectrum of RBC after exposure to HeNe laser shows a significant decrease in absorbance. The FTIR spectrum of non irradiated RBC clearly show the peaks due to O-H (free group), C=O (amide I group), N=O (nitro group), C-O (anhydride group) and C-H (aromatic group). Laser radiation changes in transmittance in FTIR spectra related to C=O group and percentage of transmittance increases for O-H, C=C, N=O, C-O and C-H group.

  3. The effect of low-level laser irradiation (In-Ga-Al-AsP - 660 nm) on melanoma in vitro and in vivo.

    Science.gov (United States)

    Frigo, Lúcio; Luppi, Juliana S S; Favero, Giovani M; Maria, Durnavei A; Penna, Sócrates C; Bjordal, Jan M; Bensadoun, Rene J; Lopes-Martins, Rodrigo A B

    2009-11-20

    It has been speculated that the biostimulatory effect of Low Level Laser Therapy could cause undesirable enhancement of tumor growth in neoplastic diseases. The aim of the present study is to analyze the behavior of melanoma cells (B16F10) in vitro and the in vivo development of melanoma in mice after laser irradiation. We performed a controlled in vitro study on B16F10 melanoma cells to investigate cell viability and cell cycle changes by the Tripan Blue, MTT and cell quest histogram tests at 24, 48 and 72 h post irradiation. The in vivo mouse model (male Balb C, n = 21) of melanoma was used to analyze tumor volume and histological characteristics. Laser irradiation was performed three times (once a day for three consecutive days) with a 660 nm 50 mW CW laser, beam spot size 2 mm(2), irradiance 2.5 W/cm(2) and irradiation times of 60s (dose 150 J/cm(2)) and 420s (dose 1050 J/cm(2)) respectively. There were no statistically significant differences between the in vitro groups, except for an increase in the hypodiploid melanoma cells (8.48 +/- 1.40% and 4.26 +/- 0.60%) at 72 h post-irradiation. This cancer-protective effect was not reproduced in the in vivo experiment where outcome measures for the 150 J/cm(2) dose group were not significantly different from controls. For the 1050 J/cm(2) dose group, there were significant increases in tumor volume, blood vessels and cell abnormalities compared to the other groups. LLLT Irradiation should be avoided over melanomas as the combination of high irradiance (2.5 W/cm(2)) and high dose (1050 J/cm(2)) significantly increases melanoma tumor growth in vivo.

  4. The effect of low-level laser irradiation (In-Ga-Al-AsP - 660 nm on melanoma in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Bjordal Jan M

    2009-11-01

    Full Text Available Abstract Background It has been speculated that the biostimulatory effect of Low Level Laser Therapy could cause undesirable enhancement of tumor growth in neoplastic diseases. The aim of the present study is to analyze the behavior of melanoma cells (B16F10 in vitro and the in vivo development of melanoma in mice after laser irradiation. Methods We performed a controlled in vitro study on B16F10 melanoma cells to investigate cell viability and cell cycle changes by the Tripan Blue, MTT and cell quest histogram tests at 24, 48 and 72 h post irradiation. The in vivo mouse model (male Balb C, n = 21 of melanoma was used to analyze tumor volume and histological characteristics. Laser irradiation was performed three times (once a day for three consecutive days with a 660 nm 50 mW CW laser, beam spot size 2 mm2, irradiance 2.5 W/cm2 and irradiation times of 60s (dose 150 J/cm2 and 420s (dose 1050 J/cm2 respectively. Results There were no statistically significant differences between the in vitro groups, except for an increase in the hypodiploid melanoma cells (8.48 ± 1.40% and 4.26 ± 0.60% at 72 h post-irradiation. This cancer-protective effect was not reproduced in the in vivo experiment where outcome measures for the 150 J/cm2 dose group were not significantly different from controls. For the 1050 J/cm2 dose group, there were significant increases in tumor volume, blood vessels and cell abnormalities compared to the other groups. Conclusion LLLT Irradiation should be avoided over melanomas as the combination of high irradiance (2.5 W/cm2 and high dose (1050 J/cm2 significantly increases melanoma tumor growth in vivo.

  5. Intraoperative OCT Pachymetry in Patients Undergoing Dextran-Free Riboflavin UVA Accelerated Corneal Collagen Crosslinking.

    Science.gov (United States)

    Rechichi, Miguel; Mazzotta, Cosimo; Daya, Sheraz; Mencucci, Rita; Lanza, Michele; Meduri, Alessandro

    2016-10-01

    To assess intraoperative corneal pachymetry in patients undergoing accelerated corneal collagen crosslinking with a dextran-free riboflavin solution. Prospective, non-comparative, multicenter interventional study. Thirty patients with progressive keratoconus were enrolled in the study from the Siena Crosslinking Center™ in Siena, Italy and the Eye Center in Catanzaro, Italy. The mean age was 26.9 ± 6.5 years. Patients underwent pulsed light accelerated crosslinking (PL-ACXL) by KXL I UV-A source (Avedro Inc., Waltham, MS, USA) with 8 min (1 s on/1 s off) of UV-A exposure, 30 mW/cm(2) and an energy dose of 7.2 J/cm(2). Corneal stroma was soaked with a dextran-free 0.1% riboflavin solution plus hydroxyl-propyl methylcellulose (HPMC) (VibeX Rapid, Avedro). Intraoperative corneal thickness was preoperatively (PRE-OP) evaluated by corneal optical coherence tomography (iVUE Optovue Inc., Fremont, CA, USA) after epithelium removal (EPI-R), after 10 min of riboflavin soaking (RS) and after UV-A irradiation (IR). Statistical analysis was conducted using a Wilcoxon test and SPSS v16.0. A p-value of collagen crosslinking by using dextran free HPMC 0.1% riboflavin solution.

  6. Photo-Fenton treatment of valproate under UVC, UVA and simulated solar radiation.

    Science.gov (United States)

    Funai, Daniel Haranaka; Didier, Florian; Giménez, Jaime; Esplugas, Santiago; Marco, Pilar; Machulek, Amilcar

    2017-02-05

    The abatement of valproic acid sodium salt (VA) via photo-Fenton process was investigated to evaluate the effect of irradiation type. Three different light sources have been used: UVA (black light blue lamps, BLB reactor), UVC (UVC reactor) and simulated sunlight in a Solarbox (SB). Using the highest concentrations of Fe2+ (10mgL-1) and H2O2 (150mgL-1), 100% of VA degradation was observed in BLB and UVC devices, and 89.7% in Solarbox. Regarding mineralization, 67.4% and 76.4% of TOC conversion were achieved in BLB and UVC, respectively. In Solarbox, mineralization was negligible. Treated solutions under UVA or UVC radiation became biodegradable (BOD5/COD≥0.25), which was not observed in Solarbox where BOD5/COD achieved was only 0.20. Regarding to toxicity (Vibrio Fischeri method), all processes have promoted the overall toxicity reduction of VA solution. Transformation products were identified by a LC-ESI-TOF mass spectrometer, and degradation pathways were proposed. Operating costs and the energy needed by mg of VA removed were estimated and compared, for the different installations, showing that UVA can remove around 3 times more VA than SB and 2 times more VA than UVC, under the same conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Investigation of the bystander effect in MRC5 cells after acute and fractionated irradiation in vitro

    OpenAIRE

    Shokouhozaman Soleymanifard; Mohammad Taghi Bahreyni Toossi; Roghayeh Kamran Samani; Shokoufeh Mohebbi

    2014-01-01

    Radiation-induced bystander effect (RIBE) has been defined as radiation responses observed in nonirradiated cells. It has been the focus of investigators worldwide due to the deleterious effects it induces in nonirradiated cells. The present study was performed to investigate whether acute or fractionated irradiation will evoke a differential bystander response in MRC5 cells. A normal human cell line (MRC5), and a human lung tumor cell line (QU-DB) were exposed to 0, 1, 2, and 4Gy of single a...

  8. Treatment of progressive keratoconus by riboflavin-UVA-induced cross-linking of corneal collagen: ultrastructural analysis by Heidelberg Retinal Tomograph II in vivo confocal microscopy in humans.

    Science.gov (United States)

    Mazzotta, Cosimo; Balestrazzi, Angelo; Traversi, Claudio; Baiocchi, Stefano; Caporossi, Tomaso; Tommasi, Cristina; Caporossi, Aldo

    2007-05-01

    To assess ultrastructural stromal modifications after riboflavin-UVA-induced cross-linking of corneal collagen in patients with progressive keratoconus. This was a second-phase prospective nonrandomized open study in 10 patients with progressive keratoconus treated by riboflavin-UVA-induced cross-linking of corneal collagen and assessed by means of Heidelberg Retinal Tomograph II Rostock Corneal Module (HRT II-RCM) in vivo confocal microscopy. The eye in the worst clinical condition was treated for each patient. Treatment under topical anesthesia included corneal deepithelization (9-mm diameter) and instillation of 0.1% riboflavin phosphate-20% dextran T 500 solution at 5 minutes before UVA irradiation and every 5 minutes for a total of 30 minutes. UVA irradiation was 7 mm in diameter. Patients were assessed by HRT II-RCM confocal microscopy in vivo at 1, 3, and 6 months after treatment. Rarefaction of keratocytes in the anterior and intermediate stroma, associated with stromal edema, was observed immediately after treatment. The observation at 3 months after the operation detected keratocyte repopulation in the central treated area, whereas the edema had disappeared. Cell density increased progressively over the postoperative period. At approximately 6 months, keratocyte repopulation was complete, accompanied by increased density of stromal fibers. No endothelial damage was observed at any time. Reduction in anterior and intermediate stromal keratocytes followed by gradual repopulation has been confirmed directly in vivo in humans by HRT II-RCM confocal microscopy after riboflavin-UVA-induced corneal collagen cross-linking.

  9. Cinétique de l'apoptose induite après irradiation α in vitro de macrophages alvéolaires de rat

    Science.gov (United States)

    Lizon, C.; Poncy, J. L.; Fritsch, P.

    1998-04-01

    After in vitro α-particle irradiation of rat alveolar macrophages, apoptosis and necrosis induction have been quantified. Results show a different radiosensitivity depending on time after cell plating and a maximal apoptosis frequency which occurred 48 hours after the end of irradiation. L'induction d'apoptose et de nécrose a été quantifiée d'après irradation α in vitro de macrophages alvéolaires de rats. Les résultats montrent une radiosensibilité dépendante du temps de culture et l'apparition d'un pic d'apoptose 48 heures après la fin de l'irradiation.

  10. Conservative treatment of keratoconus by riboflavin-uva-induced cross-linking of corneal collagen: qualitative investigation.

    Science.gov (United States)

    Mazzotta, C; Traversi, C; Baiocchi, S; Sergio, P; Caporossi, T; Caporossi, A

    2006-01-01

    To assess corneal tissue modifications after riboflavin-UVA-induced cross-linking of corneal collagen in patients with progressive keratoconus as well as regeneration of epithelium and subepithelial nerve plexus by in vivo HRT II system confocal microscopy in humans. Ten patients with progressive keratoconus were treated by riboflavin-UVA-induced cross-linking of corneal collagen, involving assessment of ultrastructural modifications of the corneal epithelium and subepithelial nerve plexus by HRT II system confocal microscopy. Treatment included instillation of 0.1% riboflavin-20% dextrane solution 5 minutes before UVA irradiation and every 5 minutes for a total of 30 minutes. Radiant energy was 3 mW/cm 2 or 5.4 Joule/cm 2 and the source was dual UVA (370 nm) light-emitting LED. The protocol included the operation followed by antibiotic medication and eye dressing with a soft therapeutic contact lens. Changes in epithelium and subepithelial and stromal nerve plexus were assessed by HRT II system confocal microscopy in vivo. After 5 days of soft contact lens wearing, corneal epithelium has a regular morphology and density. Disappearance of subepithelial stromal nerve fibers was observed in the central irradiated area where, 1 month after the operation, initial reinnervation was microscopically observed. No changes in nerve fibers were observed in the peripheral untreated with a clear lateral transition between the two areas. Six months after the operation, the anterior subepithelial stroma was recolonized by nerve fibers with restoration of corneal sensitivity. HRT II system confocal microscopy confirms corneal epithelium restore and re-innervation after riboflavin-UVA-induced collagen cross-linking directly in vivo in humans.

  11. In vitro pulp chamber temperature rise from irradiation and exotherm of flowable composites.

    Science.gov (United States)

    Baroudi, Kusai; Silikas, Nick; Watts, David C

    2009-01-01

    The aim of this study was to investigate the pulpal temperature rise induced during the polymerization of flowable and non-flowable composites using light-emitting diode (LED) and halogen (quartz-tungsten-halogen) light-curing units (LCUs). Five flowable and three non-flowable composites were examined. Pulpal temperature changes were recorded over 10 min in a sample primary tooth by a thermocouple. A conventional quartz-tungsten-halogen source and two LEDs, one of which was programmable, were used for light curing the resin composites. Three repetitions per material were made for each LCU. There was a wide range of temperature rises among the materials (P Temperature rises ranged between 1.3 degrees C for Filtek Supreme irradiated by low-power LED and 4.5 degrees C for Grandio Flow irradiated by high-power LED. The highest temperature rises were observed with both the LED high-power and soft-start LCUs. The time to reach the exothermic peak varied significantly between the materials (P temperature rise is related to both the radiant energy output from LCUs and the polymerization exotherm of resin composites. A greater potential risk for heat-induced pulp damage might be associated with high-power LED sources. Flowable composites exhibited higher temperature rises than non-flowable materials, because of higher resin contents.

  12. Effect of rutin on virus inactivation by AMT in combination with ultraviolet-A irradiation in platelet concentrates

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Yoshiko; Abe, Hideki; Ikebuchi, Kenji; Sekiguchi, Sadayoshi [Hokkaido Red Cross Blood Center, Sapporo (Japan)

    1999-10-01

    Treatment with psoralens and ultraviolet-A (UVA) irradiation have been found to be effective for virus sterilization of platelet concentrates (PCs). We report here a virus inactivation method using a combination of psoralen derivative 4'-aminomethyl-4,5', 8-trimethylpsoralen (AMT) and UVA irradiation (AMT/UVA). Further, we also investigated the effect of rutin, a radical scavenger, on the inactivation of vesicular stomatitis virus (VSV) as a model virus administered in PCs and platelet functions were investigated. Spiked VSV (about 5log{sub 10}) in PCs was inactivated by a combination of AMT (50 {mu}g/ml) and 5.2 J/cm{sup 2} UVA irradiation in the absence of rutin. To obtain equivalent levels of VSV kill in the presence of 0.35 mM rutin, treatment with 13.0 J/cm{sup 2} of UVA irradiation with AMT was performed. When PCs were treated under each condition in which 5log{sub 10} VSV was inactivated by AMT/UVA with or without rutin, platelet aggregation function was maintained for more than 80% of untreated platelets. These findings indicate that the presence of rutin during AMT/UVA treatment conferred no beneficial effect. In addition, overnight storage of PCs with AMT induced 40% loss of platelet aggregation in response to 10{mu}M ADP. The findings suggest that UVA irradiation is required immediately after the addition of AMT. (author)

  13. Polymorphous light eruption (PLE) and a new potent antioxidant and UVA-protective formulation as prophylaxis.

    Science.gov (United States)

    Hadshiew, I M; Treder-Conrad, C; v Bülow, R; Klette, E; Mann, T; Stäb, F; Moll, I; Rippke, F

    2004-08-01

    Polymorphous light eruption (PLE) is the most common photodermatosis. While its etiology still remains elusive, pathogenesis seems to involve UVA-induced oxidative stress and subsequent deregulation of antioxidative immune responses. Only few and often ineffective prophylactic and therapeutic measures exist to date. In our randomized, double-blind, placebo-controlled clinical study, we compared the efficacy of a new topical formulation, consisting of 0.25%alpha-glucosylrutin (AGR) (a natural, modified flavonoid), 1% tocopheryl acetate (vitamin E) and a broad-spectrum, highly UVA-protective sunscreen (SPF 15) in a hydrodispersion gel vehicle, to a sunscreen-only gel and vehicle. Thirty patients with a history of PLE were pretreated with either the above formulation, a similar preparation (with the same concentration for vitamin E and AGR, but a different UV filter system), placebo or a SPF 15 sunscreen-only gel, 30 min prior to daily photoprovocation with UVA irradiations of 60-100 J/cm(2) to 5 x 5 cm(2) areas on the upper arms. After 4 days, results revealed a statistically highly significant difference (PPLE. While only one patient developed clinical signs of PLE with accompanying itch in the area treated with the new antioxidant UV-protective gel formulation, 62.1% of the placebo-treated areas and 41.3% of the sunscreen-only treated areas showed mild to moderate signs of PLE. Combining a potent antioxidant with a broad-spectrum, highly UVA-protective sunscreen is far more effective in preventing PLE than sunscreen alone or placebo and should thus be employed as the prophylaxis of choice for PLE.

  14. Phytotherapeutics oridonin and ponicidin show additive effects combined with irradiation in pancreatic cancer in vitro

    Directory of Open Access Journals (Sweden)

    Liermann Jakob

    2017-11-01

    Full Text Available Chemoradiation of locally advanced non-metastatic pancreatic cancer can lead to secondary operability by tumor mass reduction. Here, we analyzed radiomodulating effects of oridonin and ponicidin in pancreatic cancer in vitro. Both agents are ent-kaurane diterpenoids, extracted from Isodon rubescens, a plant that is well known in Traditional Chinese Medicine. Cytotoxic effects have recently been shown in different tumor entities for both agents.

  15. A comparative study of 632.8 and 532 nm laser irradiation on some rheological factors in human blood in vitro.

    Science.gov (United States)

    Mi, X Q; Chen, J Y; Cen, Y; Liang, Z J; Zhou, L W

    2004-03-19

    The effects of laser irradiation with 632.8 and 532 nm on rheological properties of blood were comparatively studied in vitro. Under the irradiation condition of 30 mW, laser irradiation of blood samples using a spot diameter of 5 mm with each laser, showed promising results in the modulation of hemorheological properties. When blood samples from patients with abnormally high values of erythrocyte sedimentation rate (ESR) were irradiated, the values of ESR were lowered statistically by either of the 632.8 or 532 nm lasers. The laser irradiation reduced blood viscosities at different shear rates (10-110 S(-1)) for the hyper-viscosity blood samples. Laser irradiation increased the electrophoretic mobility (EPM) of erythrocytes when the values of the sample's EPM were abnormally slow. The erythrocyte deformability was enhanced by laser irradiation when the deformability of the sample from the patients was originally poor. For verifying the improvement of laser irradiation on erythrocyte deformability, the typical erythrocyte samples with poor deformability were produced by the pre-treatment of the erythrocytes with Ca(2+). The deformability of these erythrocyte samples was also improved after laser irradiation. These results suggest that membrane-bound hemoglobin (Hbm) might be the initial site of the interaction, since Hbm is the main cause of poor deformability when erythrocytes were treated with Ca(2+). In all experiments including ESR, blood viscosity, EPM and erythrocyte deformability, the 532 nm laser demonstrated more efficient effects on modulating rheological properties than 632.8 nm laser. This wavelength effect is consistent with the absorption spectrum of hemoglobin, reflecting that hemoglobin may be one of the action targets under laser irradiation.

  16. Controlling powdery mildew (Sphaerotheca mors-uvae) of gooseberry (Ribes uva-crispa) with potassium bicarbonate and risk of phytotoxicity

    NARCIS (Netherlands)

    Wenneker, M.

    2016-01-01

    Powdery mildew (Sphaerotheca mors-uvae) severely infects young shoots, stems and fruits of gooseberry (Ribes uva-crispa). Environmental friendly and biological control measures are being sought throughout the world. Especially in organic currant growing effective control measures are needed,

  17. Mechanism of Aloe Vera extract protection against UVA: shelter of lysosomal membrane avoids photodamage.

    Science.gov (United States)

    Rodrigues, Daniela; Viotto, Ana Cláudia; Checchia, Robert; Gomide, Andreza; Severino, Divinomar; Itri, Rosangela; Baptista, Maurício S; Martins, Waleska Kerllen

    2016-03-01

    The premature aging (photoaging) of skin characterized by wrinkles, a leathery texture and mottled pigmentation is a well-documented consequence of exposure to sunlight. UVA is an important risk factor for human cancer also associated with induction of inflammation, immunosuppression, photoaging and melanogenesis. Although herbal compounds are commonly used as photoprotectants against the harmful effects of UVA, the mechanisms involved in the photodamage are not precisely known. In this study, we investigated the effects of Aloe Vera (Aloe barbadensis mil) on the protection against UVA-modulated cell killing of HaCaT keratinocytes. Aloe Vera exhibited the remarkable ability of reducing both in vitro and in vivo photodamage, even though it does not have anti-radical properties. Interestingly, the protection conferred by Aloe Vera was associated with the maintenance of membrane integrity in both mimetic membranes and intracellular organelles. The increased lysosomal stability led to a decrease in lipofuscinogenesis and cell death. This study explains why Aloe Vera extracts offer protection against photodamage at a cellular level in both the UV and visible spectra, leading to its beneficial use as a supplement in protective dermatological formulations.

  18. Ultraviolet A eye irradiation ameliorates colon carcinoma induced by azoxymethane and dextran sodium sulfate through β-endorphin and methionine-enkephalin.

    Science.gov (United States)

    Hiramoto, Keiichi; Yokoyama, Satoshi; Yamate, Yurika

    2017-03-01

    We previously reported that ultraviolet (UV) A eye irradiation reduces the ulcerative colitis induced by dextran sodium sulfate (DSS). This study examined the effects of UVA on colon carcinoma induced by azoxymethane (AOM) and DSS. We irradiated the eyes of ICR mice with UVA at a dose of 110 kJ/m2 using an FL20SBLB-A lamp for the experimental period. In mice treated with these drugs, the symptom of colon carcinoma was reduced by UVA eye irradiation. The levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in the blood were increased in AOM + DSS-treated mice; however, those levels were reduced by UVA eye irradiation. The expression of β-endorphin, methionine-enkephalin (OGF), μ-opioid receptor, and opioid growth factor receptor (OGFR) of the colon was increased in the AOM + DSS-treated mice, and these levels were increased further following UVA eye irradiation. When β-endorphin inhibitor was administered, the ameliorative effect of UVA eye irradiation was reduced, and the effect of eye irradiation disappeared entirely following the administration of naltrexone (inhibitor of both opioid receptor and OGFR). These results suggested that UVA eye irradiation exerts major effects on AOM + DSS-induced colon carcinoma. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. The effect of low- and high-power microwave irradiation on in vitro grown Sequoia plants and their recovery after cryostorage.

    Science.gov (United States)

    Halmagyi, A; Surducan, E; Surducan, V

    2017-06-24

    Two distinct microwave power levels and techniques have been studied in two cases: low-power microwave (LPM) irradiation on in vitro Sequoia plants and high-power microwave (HPM) exposure on recovery rates of cryostored (-196°C) Sequoia shoot apices. Experimental variants for LPM exposure included: (a) in vitro plants grown in regular conditions (at 24 ± 1°C during a 16-h light photoperiod with a light intensity of 39.06 μEm-2 s-1 photosynthetically active radiation), (b) in vitro plants grown in the anechoic chamber with controlled environment without microwave irradiation, and (c) in vitro plants grown in the anechoic chamber with LPM irradiation for various times (5, 15, 30, 40 days). In comparison to control plants, significant differences in shoot multiplication and growth parameters (length of shoots and roots) were observed after 40 days of LPM exposure. An opposite effect was achieved regarding the content of total soluble proteins, which decreased with increasing exposure time to LPM. HPM irradiation was tested as a novel rewarming method following storage in liquid nitrogen. To our knowledge, this is the first report using this type of rewarming method. Although, shoot tips subjected to HPM exposure showed 28% recovery following cryostorage compared to 44% for shoot tips rewarmed in liquid medium at 22 ± 1 °C, we consider that the method represent a basis and can be further improved. The results lead to the overall conclusion that LPM had a stimulating effect on growth and multiplication of in vitro Sequoia plants, while the HPM used for rewarming of cryopreserved apices was not effective to achieve high rates of regrowth after liquid nitrogen exposure.

  20. Evaluation of the cloudy sky solar UVA radiation exposures.

    Science.gov (United States)

    Parisi, A V; Downs, N; Turner, J

    2014-09-05

    The influence of cloud on the solar UVA (320-400 nm) exposures over five minute periods on a horizontal plane has been investigated. The first approach used cloud modification factors that were evaluated using the influence of clouds on the global solar exposures (310-2800 nm) and a model developed to apply these to the clear sky UVA exposures to allow calculation of the five minute UVA exposures for any cloud conditions. The second approach established a relationship between the UVA and the global solar exposures. The models were developed using the first six months of data in 2012 for SZA less than or equal to 70° and were applied and evaluated for the exposures in the second half of 2012. This comparison of the modelled exposures for all cloud conditions to the measured data provided an R(2) of 0.8 for the cloud modification model, compared to an R(2) of 0.7 for the UVA/global model. The cloud modification model provided 73% of the five minute exposures within 20% of the measured UVA exposures. This was improved to 89% of the exposures within 20% of the measured UVA exposures for the cases of cloud with the sun not obscured. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. [Intervention of nicotinamide on skin melanin genesis after UVA exposed].

    Science.gov (United States)

    Patam, Muhammad; Jin, Xi-peng; Zhang, Yu-bin; Pan, Jian-ying; Shen, Guang-zu

    2007-08-01

    To investigate the interference effect of nicotinamide on UVA-induced melanin genesis and melanin transport in human skin melanocyte. The optimum UVA dose expected to cause cell proliferation: 0.2 J/cm(2), nicotinamide was added immediately after the 0.2 J/cm(2) UVA exposure and the melanin content, cell cycles, cell apoptosis and mRNA express level were measured respectively. Melanin content in melanocytes was increased significantly after exposed to 0.2 J/cm(2) UVA. Melanin content in melanocytes was decreased after treatment with 10.0 mmol/ml nicotinamide following UVA exposure, but the cell cycles and the cell apoptosis rate were not significantly altered. mRNA express levels of TYR, TRP-1 were modulated by nicotinamide. Nicotinamide has more effect on decreasing melanin genesis after UVA exposure, nicotinamide also plays a role in modulating the mRNA express of TYR, TRP-1 gene. It is possible to consider nicotinamide as an efficient and safe sun screen to provide a certain level of protection for UVA exposed skin.

  2. The Effect of Solar Irradiated Vibrio cholerae on the Secretion of Pro-Inflammatory Cytokines and Chemokines by the JAWS II Dendritic Cell Line In Vitro.

    Science.gov (United States)

    Ssemakalu, Cornelius Cano; Ubomba-Jaswa, Eunice; Motaung, Keolebogile Shirley; Pillay, Michael

    2015-01-01

    The use of solar irradiation to sterilize water prior to its consumption has resulted in the reduction of water related illnesses in waterborne disease endemic communities worldwide. Currently, research on solar water disinfection (SODIS) has been directed towards understanding the underlying mechanisms through which solar irradiation inactivates the culturability of microorganisms in water, enhancement of the disinfection process, and the health impact of SODIS water consumption. However, the immunological consequences of SODIS water consumption have not been explored. In this study, we investigated the effect that solar irradiated V. cholerae may have had on the secretion of cytokines and chemokines by the JAWS II dendritic cell line in vitro. The JAWS II dendritic cell line was stimulated with the different strains of V. cholerae that had been: (i) prepared in PBS, (ii) inactivated through a combination of heat and chemical, (iii) solar irradiated, and (iv) non-solar irradiated, in bottled water. As controls, LPS (1 μg/ml) and CTB (1 μg/ml) were used as stimulants. After 48 hours of stimulation the tissue culture media from each treatment was qualitatively and quantitatively analysed for the presence of IL-1α, IL-1β, IL-6, IL-7, IL-10, IL-12p40, IL-12p70, IL-15, MIP-1α, MIP-1β, MIP-2, RANTES, TNF-α, IL-23 and IL-27. Results showed that solar irradiated cultures of V. cholerae induced dendritic cells to secrete significant (pSODIS treated water.

  3. Effects of low-level laser irradiation on the pathogenicity of Candida albicans: in vitro and in vivo study.

    Science.gov (United States)

    Seyedmousavi, Seyedmojtaba; Hashemi, Seyed Jamal; Rezaie, Sasan; Fateh, Mohsen; Djavid, Gholamreza Esmaeeli; Zibafar, Ensieh; Morsali, Farhad; Zand, Nasrin; Alinaghizadeh, Mohammadreza; Ataie-Fashtami, Leila

    2014-06-01

    The purpose of this study was to evaluate the effects of low-level laser irradiation (LLLI) on the in vitro growth characteristics and in vivo pathogenicity of Candida albicans in a murine model in the absence of a photosensitizer. C. albicans is an opportunistic commensal organism that causes a wide variety of diseases in human beings, ranging from superficial infections to life-threatening invasive candidiasis. The incidence of C. albicans infection is increasing, because of the greater frequency of acquired immunodeficiency conditions. A high recurrence rate has been reported for vulvovaginal and oral candidiasis, despite the best available treatments. Therefore, the search for new treatment modalities seems quite rational. Candida culture plates were exposed to common clinical energies of LLLI: 3, 5, 10, and 20 J at 685 nm (BTL Laser 5000, Medicinos Projektai, Czech Republic, Prague, max power output 50 mW) and 3, 5, 10, 30, and 50 J at 830 nm (BTL Laser 5000, Medicinos Projektai, Czech Republic, Prague, max power output 400 mW). Following LLLI with energies >10 J at both 685 and 830 nm wavelengths, statistically significant effects were observed in vitro on the turbidimetric growth kinetics of C. albicans and in vivo on the survival rate of infected mice (p value ≤ 0.05). Therefore, this energy could be considered a threshold for clinical investigation. Translating our data into the clinical setting, it can be proposed that a direct laser-based approach without using a photosensitizing dye can significantly reduce the pathogenicity of Candida albicans. It can also be concluded that laser light at specific wavelengths could be a possible promising novel treatment for superficial and mucocutaneous C. albicans infections.

  4. The respiratory chain is the cell's Achilles' heel during UVA inactivation in Escherichia coli.

    Science.gov (United States)

    Bosshard, Franziska; Bucheli, Margarete; Meur, Yves; Egli, Thomas

    2010-07-01

    Solar disinfection (SODIS) is used as an effective and inexpensive tool to improve the microbiological quality of drinking water in developing countries where no other means are available. Solar UVA light is the agent that inactivates bacteria during the treatment. Damage to bacterial membranes plays a crucial role in the inactivation process. This study showed that even slightly irradiated cells (after less than 1 h of simulated sunlight) were strongly affected in their ability to maintain essential parts of their energy metabolism, in particular of the respiratory chain (activities of NADH oxidase, succinate oxidase and lactate oxidase were measured). The cells' potential to generate ATP was also strongly inhibited. Many essential enzymes of carbon metabolism (glucose-6-phosphate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, lactate dehydrogenase and malate dehydrogenase) and defence against oxidative stress (catalases and glutathione-disulfide reductase) were reduced in their activity during SODIS. The work suggests that damage to membrane enzymes is a likely cause of membrane dysfunction (loss of membrane potential and increased membrane permeability) during UVA irradiation. In this study, the first targets on the way to cell death were found to be the respiratory chain and F(1)F(0) ATPase.

  5. Effect on topical 5-methoxypsoralen on tumorigenesis induced in albino and pigmented hairless mouse skin by UV irradiation.

    Science.gov (United States)

    Reeve, V E; Greenoak, G E; Boehm-Wilcox, C; Canfield, P J; Gallagher, C H

    1990-05-01

    A new line of the Skh:HRII hairless pigmented mouse (black juvenile coat) is described which has been selectively bred for the capacity to respond consistently to simulated solar UV radiation with a continuous and strong tan. This mouse demonstrates a degree of protection from chronic UV-induced tumorigenesis when compared with the Skh:HRI hairless albino mouse, and has been used here to study the effect of induced melanogenesis on phototumorigenesis. Mice were irradiated for 10 weeks with incremental doses of simulated solar UV radiation (UVA + B) from a fluorescent tube source which induced tumours in 100% of albino mice and 93% of black mice by 200 days (minimally oedemal), or with 60% of this dose (sub-oedemal) which induced tumours in 85% of albino mice and 65% of black mice. Mice were also exposed to the UVA component of these radiation sources, obtained by window glass filtration. The effect of topical 5-methoxypsoralen (5-MOP) was examined, at either 0.003% with minimally oedemal UVA + B or its UVA component alone, or at 0.01% with sub-oedemal UVA + B or its UVA component alone, in both albino and black mice. The 5-MOP concentrations were selected as the maximum concentration which did not increase the erythema and oedema responses after a single exposure to minimally oedemal or sub-oedemal UVA + B. At 200 days, the tumorigenic response to sub-oedemal UVA + B was significantly increased by topical 5-MOP, to 100% in albinos and 93% in black mice. In contrast, tumorigenesis in response to minimally oedemal UVA + B was unaffected by topical 5-MOP. The UVA component alone of either irradiation regime was not tumorigenic under these conditions. When combined with topical 5-MOP, the UVA of minimally oedemal UVA + B became moderately tumorigenic, and resulted in a tumour incidence of 23% in albinos and 14.5% in black mice. However, the UVA component of sub-oedemal UVA + B, when combined with topical 5-MOP, was highly tumorigenic specifically in albino mice

  6. Effect of Low Power Laser Irradiation on the Ability of Cell Growth and Myogenic Differentiation of Myoblasts Cultured In Vitro

    Directory of Open Access Journals (Sweden)

    Cui-Ping Zhang

    2014-01-01

    Full Text Available As a therapeutic modality, low power laser irradiation (LPLI has been used clinically in the treatment of skeletal muscle injuries and other myopathic conditions, but the cellular and molecular mechanisms attributed to this therapy were still unclear. Myoblasts are a type of myogenic stem cells quiescence in mature skeletal muscle fibers and are considered as the source cells during the regenerating process. The purpose of this paper was to investigate the effects of LPLI on the proliferation and myogenic differentiation of the cultured myoblasts and to find out the major candidates responsible for LPLI-induced muscle regeneration in vivo. In this study, primary rat myoblasts were exposed to helium-neon (He-Ne laser. Cell proliferation, differentiation, and the cellular responses to LPLI were monitored by using morphological observation and molecular biological methods. It was found that LPLI at a certain fluence could increase the cell growth potential for myoblasts and further induce more cells entering into S phase of the mitotic cycle as indicated by high levels of bromodeoxyuridine (BrdU incorporation, while at the same time inhibiting their in vitro differentiation and decreasing the expression of myogenic regulatory genes to a certain extent. Taken together, these results provide experimental evidence for the clinical applications of LPLI in regenerating skeletal muscle.

  7. The Effect in Vitro of Ionizing Irradiation and Small Rises in Temperature on the Uptake and Release of Labelled Lipids by the Human Erythrocyte Membrane

    DEFF Research Database (Denmark)

    Hansen, Heinz Johs. Max; Karle, H.; Stender, S.

    1978-01-01

    1. The effect of X-irradiation (50 000 rad) and an increase in temperature from 37 to 42° C on the synthesis, uptake and release of labelled lipids by erythrocytes was studied in plasma incubations in vitro. 2. Both irradiation and a rise in temperature resulted in an enhanced synthesis of [32P......]phosphatidic acid in the erythrocytes. 3. The uptake by the erythrocytes of 14C- and 3H-labelled cholesterol, [14C, 32P]phosphatidylethanolamine and [14C, 32P]phosphatidylcholine from plasma lipoproteins was increased by a rise in temperature but not by irradiation. These labelled lipids were apparently taken up...... in the ratio in which they were found in plasma. They were not released from the erythrocytes in the same manner....

  8. In vitro effects of tetraiodothyroacetic acid combined with X-irradiation on basal cell carcinoma cells.

    Science.gov (United States)

    Leith, John T; Davis, Paul J; Mousa, Shaker A; Hercbergs, Aleck A

    2017-02-16

    We investigated radiosensitization in an untreated basal cell carcinoma (TE.354.T) cell line and post-pretreatment with tetraiodothyroacetic acid (tetrac) X 1 h at 37°C, 0.2 and 2.0 µM tetrac. Radioresistant TE.354.T cells were grown in modified medium containing fibroblast growth factor-2, stem cell factor-1 and a reduced calcium level. We also added reproductively inactivated (30 Gy) "feeder cells" to the medium. The in vitro doubling time was 34.1 h, and the colony forming efficiency was 5.09 percent. These results were therefore suitable for clonogenic radiation survival assessment. The 250 kVp X-ray survival curve of control TE.354.T cells showed linear-quadratic survival parameters of αX-ray = 0.201 Gy(-1) and βX-ray = 0.125 Gy(-2). Tetrac concentrations of either 0.2 or 2.0 µM produced αX-ray and βX-ray parameters of 2.010 and 0.282 Gy(-1) and 2.050 and 0.837 Gy(-2), respectively. The surviving fraction at 2 Gy (SF2) for control cells was 0.581, while values for 0.2 and 2.0 µM tetrac were 0.281 and 0.024. The SF2 data show that tetrac concentrations of 0.2 and 2.0 µM sensitize otherwise radioresistant TE.354.T cells by factors of 2.1 and 24.0, respectively. Thus, radioresistant basal cell carcinoma cells may be radiosensitized pharmacologically by exposure to tetrac.

  9. Microwave-Assisted Synthesis of Fe3O4Nanocrystals with Predominantly Exposed Facets and Their Heterogeneous UVA/Fenton Catalytic Activity.

    Science.gov (United States)

    Zhong, Yuanhong; Yu, Lin; Chen, Zhi-Feng; He, Hongping; Ye, Fei; Cheng, Gao; Zhang, Qianxin

    2017-08-30

    Fe 3 O 4 nanocrystals with five different morphologies (i.e., nanospheres, nanorods, nanocubes, nano-octahedrons, and nanoplates) were acquired using a simple, efficient, and economic microwave-assisted oxidation technique. The microstructure, morphology, predominant exposed facets, and iron atom local environment of Fe 3 O 4 were revealed by powder X-ray diffraction (PXRD), scanning transmission electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectrometer (XPS), and Mössbauer spectrum. We demonstrated that the heterogeneous UVA/Fenton catalytic activities of Fe 3 O 4 nanocrystals are morphology/facets dependent. Under UVA irradiation, the catalytic activity of the as-prepared Fe 3 O 4 was in the sequence of nanospheres > nanoplates > nano-octahedrons ≈ nanocubes > nanorods > nano-octahedrons (by coprecipitation). The dominating factor for the catalytic performance was the particle size and BET specific surface area; moreover, the exposed {111} facets, which contained more Fe 2+ species, on the nanocrystal surface led to a stronger UVA/Fenton catalytic activity. Both • OH and O 2 •- radicals participated in the UVA/Fenton degradation process, and • OH played the dominant role. These morphology-controlled nanomagnetites showed great potential in applications as heterogeneous UVA/Fenton catalysts for effectively treating nonbiodegradable organic pollutants.

  10. Effect of UVC, UVB, UVA and a solar simulator on the survival of mouse melanoma cell lines differing in melanin content

    Energy Technology Data Exchange (ETDEWEB)

    Hill, H.Z.; Hill, G.J.; Cieszka, K.; Azure, M. [New Jersey Medical School, Newark, NJ (United States)

    1994-12-31

    These studies were designed to determine the survival of cells that vary in constitutive pigment levels after exposure to different UV wave lengths. The lamps employed emitted UVC (near monochromatic 254 nm), UVB (Philips TL01-88.7% of UV output is UVB), UVA (Philips HPW125-89% of output is at 365 nm) and Westinghouse FS20 (broad band UVB and UVA). Dish lids were used to cut off UVC in the UVB and FS20 experiments and 0.25 inch plate glass was used to cut off UVB in the UVA experiments. UVC photons interact with putative intracellular photosensitizers which in turn convert O{sub 2} to active oxygen species which damage DNA to produce strand breaks, cross links and base damage. UVB acts by both mechanisms. The two cell lines studied were Cloudman S91/I3 (3.6 pg melanin/cell) and the closely related S91/amel (1.2 pg melanin/cell). Attached cells were covered with Ca{sup ++} and Mg{sup ++} free PBS and irradiated in the cold. Colonies were scored after 2 weeks. The two cell lines exhibit similar survival kinetics after UVC. S91/IE is more sensitive to killing by either UVB (TL01) or UVA. However, S91/amel cells are more sensitive to killing by UVB plus UVA (FS20). It is clear that UV of different qualities can interact to produce effects that would not be predicted based on responses to monochromatic wave lengths.

  11. In vitro Protective Effect of Ganoderol A Isolated from ...

    African Journals Online (AJOL)

    Purpose: To evaluate the ultraviolet A (UVA) protection and anti-inflammatory activity of ganoderol A extracted from Ganodermalucidum. Methods: The cytotoxicity and in vitro protective effect of ganoderol A against UVA damage were evaluated by MTT assay. Apoptosis and cell-cycle arrest of NIH/3T3 fibroblast cells were ...

  12. Obtaining apple haploid plants (Malus X domestica Borkh. ) from in situ parthenogenesis induced by irradiated pollen and in vitro culture of immature seeds

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y.X.; Lespinasse, Y.; Chevreau, E.

    1988-08-01

    Two apple varieties, ''Erovan'' and ''Lodi'', have been pollinated with pollen carrying the marker gene R irradiated by gamma rays from Cobalt 60 with doses of 500, 1000 and 1500 Gy. By in vitro cultures of the immature seeds removed 7 to 13 weeks after pollination, haploid plants (2n=x=17) have been obtained from ''Erovan''.

  13. Mechanisms associated with the expression of cisplatin resistance in a human ovarian tumor cell line following exposure to fractionated x-irradiation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Dempke, W.C.M.; Shellard, S.A.; Hosking, L.K.; Hill, B.T. (Imperial Cancer Research Fund, London (United Kingdom). Labs.); Fichtinger-Schepman, A.M.J. (TNO Medical Biological Laboratory, Rijswijk (Netherlands))

    1992-07-01

    Interactions between cisplatin (CDDP) and irradiation are of potential significance for the combined modality treatment of cancer. To identify parameters associated with CDDP resistance, the human ovarian carcinoma cell line SK-OV-3/P was pre-exposed to fractionated X-irradiation in vitro. The resultant subline (SK-OV-3/DXR-10) proved 2-fold resistant to CDDP, but not to acute X-irradiation. Consistent with unaltered dihydrofolate reductase and thymidylate synthase activities, SK-OV-3/DXR-10 cells were neither cross-resistant to methotrexate nor to 5-fluorouracil. Verapamil significantly enhanced CDDP-induced cytotoxicity in the resistant DXR-10 subline, but not in the parental cells. Resistance in the SK-OV-3/DXR-10 cells was associated with significantly decreased cisplatin uptake. After an 18 h post-treatment incubation the parental cell line appeared proficient in the removal of the intrastrand adduct Pt-AG, but deficient in removing the major adduct Pt-GG and the difunctional Pt-(GMP)[sub 2] lesion, whilst the DXR-10 resistant subline appeared proficient in removal of all four Pt-DNA adducts. DNA polymerases [alpha] and [beta] activities, however, were comparable in both cell lines. These data implicate both enhanced repair and increased tolerance of DNA damage as mechanisms of resistance to CDDP resulting from in vitro exposure of a human ovarian carcinoma cell line to fractionated X-irradiation. (author).

  14. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    Science.gov (United States)

    Taghinejad-Roudbaneh, M.; Ebrahimi, S. R.; Azizi, S.; Shawrang, P.

    2010-12-01

    The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased ( Pcanola meal at doses of 45 kGy decreased ( Pcanola meal at doses of 15 and 30 kGy was improved ( Pcanola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal.

  15. High-intensity corneal collagen crosslinking with riboflavin and UVA in rat cornea.

    Science.gov (United States)

    Zhu, Yirui; Reinach, Peter S; Zhu, Hanlei; Tan, Qiufan; Zheng, Qinxiang; Qu, Jia; Chen, Wei

    2017-01-01

    Corneal collagen cross-linking (CXL) halts human corneal ectasias progression by increasing stromal mechanical stiffness. Although some reports describe that this procedure is effective in dealing with some infectious and immunologic corneal thinning diseases, there is a need for more animal models whose corneal thickness more closely resemble those occurring in these patients. To meet this need, we describe here high-intensity protocols that are safe and effective for obtaining CXL in rat corneas. Initially, a range of potentially effective UVA doses were evaluated based on their effectiveness in increasing tissue enzymatic resistance to dissolution. At UVA doses higher than a threshold level of 0.54 J/cm2, resistance to enzymatic digestion increased relative to that in non-irradiated corneas. Based on the theoretical threshold CXL dose, a CXL regimen was established in which the UVA tissue irradiance was 9 mW/cm2, which was delivered at doses of either 2.16, 2.7 or 3.24 J/cm2. Their dose dependent effects were evaluated on ocular surface morphological integrity, keratocyte apoptotic frequency, tissue thickness and endothelial cell layer density. Doses of 2.16 and 2.7 J/cm2 transiently decreased normal corneal transparency and increased thickness. These effects were fully reversed after 14 days. In contrast, 3.24 J/cm2 had more irreversible side effects. Three days after treatment, apoptotic frequency in the CXL-2.16 group was lower than that at higher doses. Endothelial cell losses remained evident only in the CXL-3.24 group at 42 days posttreatment. Stromal fiber thickening was evident in all the CXL-treated groups. We determined both the threshold UVA dose using the high-intensity CXL procedure and identified an effective dose range that provides optimal CXL with minimal transient side effects in the rat cornea. These results may help to provide insight into how to improve the CXL outcome in patients afflicted with a severe corneal thinning disease.

  16. Carcinogenesis induced by UVA (365-nm) radiation: the dose-time dependence of tumor formation in hairless mice.

    Science.gov (United States)

    de Laat, A; van der Leun, J C; de Gruijl, F R

    1997-05-01

    Although ultraviolet B (UVB wavelengths 280-315 nm) dominates the carcinogenic effect of sunlight, ultraviolet A (UVA 315-400 nm) is estimated to contribute 10-20% to the carcinogenic dose; a substantial background that is not affected by a depletion of the ozone layer. Furthermore, certain high-power modern tanning lamps emit mainly long wave UVA (UVA1; 340-400 nm). For a proper risk estimate of UVA exposure its carcinogenicity relative to that of UVB exposure needs to be determined more accurately. To this end we determined the dose-time relationship for skin tumor induction in hairless mice that were irradiated daily with custom-made Philips 365-nm sources. Irradiation of the group exposed to the highest of the four daily doses (430, 240, 140 and 75 kJ/m2) had to be discontinued because severe scratching set in after 3 months (no tumors). In the lower dose-groups the prevalence curves for skin carcinomas (percentage of tumor-bearing mice versus logarithm of time) ran virtually parallel, and were similar to those found with daily UVB exposure. However, the relationship between the daily dose (D) and the median tumor induction time (t50) appeared to differ: with UVB we found that t50 D(r) = constant, with r = 0.6, whereas with UVA1 we found r approximately 0.4. This would imply that 365-nm carcinogenesis shows less of a dose-dependency than UVB carcinogenesis, and that 365-nm radiation becomes more carcinogenic, relative to UVB, as the daily doses are lowered. This relative shift at low doses complicates extrapolation of UVB to UVA risks in humans. Based on the t50 from the lowest dose-group we found that the carcinogenicity at 365 nm (per J/m2) is 0.9 x 10(-4) times that at 293 nm, the wavelength of maximum carcinogenicity in hairless mice. This result for 365-nm carcinogenicity falls well within the margins of error of the wavelength dependency that was estimated earlier from experiments with broadband UV sources.

  17. Chromosomes and irradiation: in vitro study of the action of X-rays on human lymphocytes; Chromosomes et radiations: etude in vitro de l'action des rayons X sur les lymphocytes humains

    Energy Technology Data Exchange (ETDEWEB)

    Mouriquand, C.; Patet, J.; Gilly, C.; Wolff, C

    1966-07-01

    Radioinduced chromosomal aberrations were studied in vitro on leukocytes of human peripheral blood after x irradiation at 25, 50, 100, 200, and 300 R. The numeric and structural anomalies were examined on 600 karyotypes. The relationship between these disorders and the dose delivered to the blood are discussed. An explanation on their mechanism of formation is tentatively given. (authors) [French] L'etude in vitro des anomalies chromosomiques radioinduites a ete pratiquee sur des leucocytes de sang peripherique preleve chez 4 sujets et irradie aux doses de 25, 50, 100, 200, 300 R. Les aberrations numeriques et structurales ont ete examinees sur 600 caryotypes. Les rapports entre ces anomalies et les doses appliquees sont etudies. Une hypothese sur leur mecanisme de formation est avancee. (auteurs)

  18. Development of TiO2 powder-coated food packaging film and its ability to inactivate Escherichia coli in vitro and in actual tests.

    Science.gov (United States)

    Chawengkijwanich, Chamorn; Hayata, Yasuyoshi

    2008-04-30

    Titanium dioxide (TiO2) has attracted a great deal of attention as a photocatalytic disinfecting material in the food and environmental industry. TiO2 has been used to inactivate a wide variety of microorganisms in many applications. In the present study, we aimed to develop a TiO2 powder-coated packaging film and clarify its ability to inactivate Escherichia coli both in vitro and in actual tests, using two different particle sizes and two types of illumination at different intensities. No inhibition effect of the testing method itself on the growth of E. coli was observed. The cells of E. coli were found to have decreased 3 log CFU/ml after 180 min of illumination by two 20 W black-light bulbs (wavelength of 300-400 nm) on TiO2-coated oriented-polypropylene (OPP) film, while E. coli decreased 1 log CFU/m with black-light illumination of uncoated OPP film. The results showed that both ultraviolet A (UVA; wavelength of 315-400 nm) alone and TiO2-coated OPP film combined with UVA reduced the number of E. coli cell in vitro, but that the reduction of E. coli cell numbers was greater by TiO2-coated OPP film combined with UVA. The antimicrobial effect of TiO2-coated film is dependent on the UVA light intensity (0, TiO2 coating on the surface of OPP film. The surviving cell numbers of E. coli on TiO2-coated film decreased 3 log and 0.35 log CFU/ml after 180 min of illumination by two 20 W black bulbs and two 20 W daylight fluorescent bulbs, respectively. Despite the lesser efficacy of the photocatalytic method with fluorescent lights, the survival of E. coli cells using this method was 50% of that using fluorescent lights alone. In the actual test, the number of E. coli cells from cut lettuce stored in a TiO2-coated film bag irradiated with UVA light decreased from 6.4 on Day 0 to 4.9 log CFU/g on Day 1, while that of an uncoated film bag irradiated with UVA light decreased from 6.4 to 6.1 log CFU/g after 1 day of storage. The result shows that the TiO2-coated film

  19. Low-Dose Gamma Irradiation of Decellularized Heart Valves Results in Tissue Injury In Vitro and In Vivo.

    Science.gov (United States)

    Helder, Meghana R K; Hennessy, Ryan S; Spoon, Daniel B; Tefft, Brandon J; Witt, Tyra A; Marler, Ronald J; Pislaru, Sorin V; Simari, Robert D; Stulak, John M; Lerman, Amir

    2016-02-01

    Decellularized heart valves are emerging as a potential alternative to current bioprostheses for valve replacement. Whereas techniques of decellularization have been thoroughly examined, terminal sterilization techniques have not received the same scrutiny. This study evaluated low-dose gamma irradiation as a sterilization method for decellularized heart valves. Incubation of valves and transmission electron microscopy evaluation after different doses of gamma irradiation were used to determine the optimal dose of gamma irradiation. Quantitative evaluation of mechanical properties was done by tensile mechanical testing of isolated cusps. Sterilized decellularized heart valves were tested in a sheep model (n = 3 [1 at 1,500 Gy and 2 at 3,000 Gy]) of pulmonary valve replacement. Valves sterilized with gamma radiation between 1,000 Gy and 3,000 Gy were found to be optimal with in vitro testing. However, in vivo testing showed deteriorating valve function within 2 months. On explant, the valve with 1,500 Gy gamma irradiation showed signs of endocarditis with neutrophils on hematoxylin and eosin staining, and positive gram stain resembling streptococcus infection. The 3,000 Gy valves had no evidence of infection, but the hematoxylin and eosin staining showed evidence of wound remodeling with macrophages and fibroblasts. Tensile strength testing showed decreased strength (0 Gy: 2.53 ± 0.98 MPa, 1,500 Gy: 2.03 ± 1.23 MPa, and 3,000 Gy: 1.26 ± 0.90 MPa) with increasing levels of irradiation. Low-dose gamma irradiation does not maintain the mechanical integrity of valves, and the balance between sterilization and damage may not be able to be achieved with gamma irradiation. Other methods of terminal sterilization must be pursued and evaluated. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  20. On the comparison of three methods of assessing beam quality for broad beam in vitro cell irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Heuskin, A.-C., E-mail: anne-catherine.heuskin@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Center for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium); Wera, A.-C., E-mail: anne-catherine.wera@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Center for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium); Riquier, H., E-mail: helene.riquier@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Unite de Recherche de Biologie Cellulaire (URBC), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium); Michiels, C., E-mail: carine.michiels@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Unite de Recherche de Biologie Cellulaire (URBC), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium); Bulgheroni, A., E-mail: antonio.bulgheroni@gmail.com [Institute for Health and Consumer Protection-EC-JRC, Ispra (Italy); Jastrzab, M., E-mail: jastrzab@agh.edu.pl [Universita degli Studi dell' Insubria, Department of Physics and Mathematics, Via Ravasi, 2-21100 Varese (Italy); Caccia, M., E-mail: Massimo.Caccia@uninsubria.it [Universita degli Studi dell' Insubria, Department of Physics and Mathematics, Via Ravasi, 2-21100 Varese (Italy); Lucas, S., E-mail: stephane.lucas@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Center for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium)

    2011-12-15

    The interaction of charged particles with living matter has recently attracted increasing interest in the field of biomedical applications such as hadron therapy, radioprotection and space radiation biology. Particle accelerators are particularly useful in this area. In vitro radiobiological studies with a broad beam configuration require beam homogeneity. The goal is to produce a dose distribution given to a cell population that is as close to uniform as possible. In this paper, we compare the results of three devices used to assess the beam quality for broad beam irradiation: a passivated implanted planar silicon (PIPS) particle detector, a position-sensitive solid state detector, which is camera-like, and a solid state nuclear track detector (CR39). The first device is a PIPS detector of 300 {mu}m nominal depletion depth and an entrance window with a thickness of about 500 A. It is collimated with a 0.5 mm aperture and mounted in air on an XY moving table as close as possible to the exit window of the beam line. The second device is a CMOS position-sensitive detector (technological process 0.6 {mu}m AMS CUA), 112 Multiplication-Sign 112 pixels, with 153 Multiplication-Sign 153 {mu}m{sup 2} pixel size. It allows the user to rapidly obtain dose uniformity over a surface of 1 Multiplication-Sign 1 cm{sup 2}. During uniformity and dose rate assessment it is placed in air at the PIPS location. For both detectors, beam profile was obtained for various proton fluxes (from {approx}5 Multiplication-Sign 10{sup 4} to 10{sup 6} particles cm{sup -2} s{sup -1}). Preliminary tests were made with CR39 using 4 MeV He{sup ++} ions. Results are analysed using Poisson distribution and cell hit probability.

  1. On the comparison of three methods of assessing beam quality for broad beam in vitro cell irradiation

    Science.gov (United States)

    Heuskin, A.-C.; Wéra, A.-C.; Riquier, H.; Michiels, C.; Bulgheroni, A.; Jastrzab, M.; Caccia, M.; Lucas, S.

    2011-12-01

    The interaction of charged particles with living matter has recently attracted increasing interest in the field of biomedical applications such as hadron therapy, radioprotection and space radiation biology. Particle accelerators are particularly useful in this area. In vitro radiobiological studies with a broad beam configuration require beam homogeneity. The goal is to produce a dose distribution given to a cell population that is as close to uniform as possible. In this paper, we compare the results of three devices used to assess the beam quality for broad beam irradiation: a passivated implanted planar silicon (PIPS) particle detector, a position-sensitive solid state detector, which is camera-like, and a solid state nuclear track detector (CR39). The first device is a PIPS detector of 300 μm nominal depletion depth and an entrance window with a thickness of about 500 Å. It is collimated with a 0.5 mm aperture and mounted in air on an XY moving table as close as possible to the exit window of the beam line. The second device is a CMOS position-sensitive detector (technological process 0.6 μm AMS CUA), 112 × 112 pixels, with 153 × 153 μm 2 pixel size. It allows the user to rapidly obtain dose uniformity over a surface of 1 × 1 cm 2. During uniformity and dose rate assessment it is placed in air at the PIPS location. For both detectors, beam profile was obtained for various proton fluxes (from ˜5 × 10 4 to 10 6 particles cm -2 s -1). Preliminary tests were made with CR39 using 4 MeV He ++ ions. Results are analysed using Poisson distribution and cell hit probability.

  2. Irradiation effect on in vitro organogenesis, callus growth and plantlet development of Gerbera jamesonii Efeito da irradiação na organogênese in vitro, crescimento de calos e desenvolvimento de plântulas de gerbera

    Directory of Open Access Journals (Sweden)

    Nor A Hasbullah

    2012-06-01

    Full Text Available The present work was carried out to study the effects of gamma irradiation on in vitro growth of explants, callus and the formation of shoots and plantlets. Irradiation is known to exhibit or inhibit the differentiation of cells and growth of plants in vitro, which helps in producing new plant varieties. Gamma irradiation is one of the physical mutagens that are widely used for mutation breeding. A gradual decline was observed in the number of shoots regenerated from irradiated petiole explants compared to control. Numbers of shoots regenerated from irradiated petiole explant cultured on Murashige & Skoog medium supplemented with 2.0 mg L-1 BAP and 0.5 mg L-1 NAA was reduced to 6.6±0.9 from 7.5±0.4 (control when explants were exposed to 20 Gray of irradiation dose. Similar observation was reported on effects of gamma irradiation on in vitro propagated plantlets. Gradual decline was observed based on plant height as the dose of gamma irradiation increased. A significant decline was observed in the fresh weight of irradiated callus compared to control. In this case, growth responses of callus were strongly influenced by the radiation dose. The fresh weight of callus was reduced to 76.4±2.2% compared to 89.7±0.5% of control when callus tissues were exposed to 20 Gy.O presente trabalho foi realizado para estudar os efeitos da radiação gama no crescimento in vitro de explantes de calos, e a formação de brotos e mudas. A irradiação é conhecida por induzir ou inibir a diferenciação de células e o crescimento das plantas in vitro, o que ajuda na produção de novas variedades vegetais. Radiação gama é um dos agentes mutagenicos que são amplamente utilizados para o melhoramento através da mutação. Um declínio gradual foi observado no número de brotos regenerados a partir de explantes de pecíolos irradiados comparado com o controle. O número de brotações regeneradas de explantes de pecíolos irradiados, cultivados em meio

  3. Influence of different iodinated contrast media on the induction of DNA double-strand breaks after in vitro X-ray irradiation.

    Science.gov (United States)

    Deinzer, Christoph K W; Danova, Daniela; Kleb, Beate; Klose, Klaus J; Heverhagen, Johannes T

    2014-01-01

    The objective of this work was to examine differences in DNA double-strand break induction in peripheral blood lymphocytes after in vitro X-ray irradiation between iodinated contrast agents. Four different iodinated X-ray contrast agents--three of them with two different iodine concentrations--and mannitol (negative control; concentration of 150 mg mannitol per ml blood) were pipetted into blood samples so that there was a concentration of 0, 7.5 or 15 mg of iodine per ml blood in the samples. Negative controls without contrast medium (0 mg of iodine per ml blood) were also processed for every irradiation dose. The tubes were exposed to 0, 20 or 500 mGy in vitro X-ray irradiation. After that, the lymphocytes were separated by using density-gradient centrifugation. Fluorescence microscopy was applied to determine the average number of γH2AX-foci per lymphocyte in the presence or absence of different contrast media or mannitol. Differences in the number of γH2AX-foci were statistically analysed by one-way ANOVA and post-hoc Tukey's honestly significant difference test. Iodinated contrast agents led to a statistically significant increase in DNA double-strand breaks after in vitro irradiation. This effect increased statistically significant with rising radiation dose and appeared independent of the contrast agent used (iopromid, iodixanol, iomeprol, iopamidol). A statistically significant difference in DNA damage between the different tested contrast agents was not found. Therefore, the increase in DNA double-strand breaks depends solely on the amount of iodine applied. For evaluation of clinical consequences, our findings could be tested in further animal studies. Copyright © 2014 John Wiley & Sons, Ltd.

  4. Effect of UV irradiation on type I collagen fibril formation in neutral collagen solutions.

    Science.gov (United States)

    Menter, J M; Patta, A M; Sayre, R M; Dowdy, J; Willis, I

    2001-06-01

    Collagens have the well-known ability to spontaneously self-associate to form fibrils at physiological temperature and neutral pH in vitro and in vivo. Because solar UV may photochemically alter collagen, the kinetics of fibril formation may be modified. Thus, we have begun a systematic study of the effect of various UV wavebands on fibril formation. Citrate-soluble calf skin collagen (Elastin Products) was dissolved at 0.05% in 0.5 M HOAc, dialyzed over 2 days into two changes of 0.0327 M phosphate buffer, pH 7.0 at 4 degrees C, and centrifuged at 48,000 x g. Photolysis was carried out at 4 degrees C with either (a) UVC (UVG-11 lamp), (b) filtered solar-simulating radiation (SSR) or UVA (SSR or UVL-21 lamp filtered with a 2.0 mm Schott WG 345 filter). Gelation was commenced by rapidly raising the temperature from 8 degrees C to 33 degrees C. Nucleation and growth were followed by turbidimetric measurements at 400 nm. UVC radiation (0-17.3 J/cm2) resulted in a dose-dependent decrease in the rate of fibril growth. Under these conditions, concomitant collagen crosslinking and degradation occurred. Fibril nucleation, a prerequisite for growth, was rapid (threshold approximately 2 min) and was not affected by UVC, UVA or SSR. SSR (0-1,320 J/cm2) caused a small decrease in growth rate and in the degree of fibril formation. UVA radiation (0-1,080 J/cm2) had a similar effect. "Direct" photochemical damage thus paralleled absorption via various collagen chromophores, with UVC>SSR approximately UVA. The presence of riboflavin (RF) resulted in groundstate interactions that markedly altered both nucleation and growth kinetics. Irradiation with 29.6 J/ cm2 UVA in the presence of RF photosensitizer caused relatively minor additional changes in fibrillation kinetics. These results collectively indicate that fibril formation is markedly dependent on specific ground state interactions and relatively insensitive to nonspecific UV damage. On the other hand, fibrils thus formed from

  5. The Effect of Solar Irradiated Vibrio cholerae on the Secretion of Pro-Inflammatory Cytokines and Chemokines by the JAWS II Dendritic Cell Line In Vitro.

    Directory of Open Access Journals (Sweden)

    Cornelius Cano Ssemakalu

    Full Text Available The use of solar irradiation to sterilize water prior to its consumption has resulted in the reduction of water related illnesses in waterborne disease endemic communities worldwide. Currently, research on solar water disinfection (SODIS has been directed towards understanding the underlying mechanisms through which solar irradiation inactivates the culturability of microorganisms in water, enhancement of the disinfection process, and the health impact of SODIS water consumption. However, the immunological consequences of SODIS water consumption have not been explored. In this study, we investigated the effect that solar irradiated V. cholerae may have had on the secretion of cytokines and chemokines by the JAWS II dendritic cell line in vitro. The JAWS II dendritic cell line was stimulated with the different strains of V. cholerae that had been: (i prepared in PBS, (ii inactivated through a combination of heat and chemical, (iii solar irradiated, and (iv non-solar irradiated, in bottled water. As controls, LPS (1 μg/ml and CTB (1 μg/ml were used as stimulants. After 48 hours of stimulation the tissue culture media from each treatment was qualitatively and quantitatively analysed for the presence of IL-1α, IL-1β, IL-6, IL-7, IL-10, IL-12p40, IL-12p70, IL-15, MIP-1α, MIP-1β, MIP-2, RANTES, TNF-α, IL-23 and IL-27. Results showed that solar irradiated cultures of V. cholerae induced dendritic cells to secrete significant (p<0.05 levels of pro-inflammatory cytokines in comparison to the unstimulated dendritic cells. Furthermore, the amount of pro-inflammatory cytokines secreted by the dendritic cells in response to solar irradiated cultures of V. cholerae was not as high as observed in treatments involving non-solar irradiated cultures of V. cholerae or LPS. Our results suggest that solar irradiated microorganisms are capable of inducing the secretion of pro-inflammatory cytokines and chemokines. This novel finding is key towards

  6. In vitro and in vivo studies on the cytotoxicity of irradiated silk fibroin against mouse melanoma tumor cell

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Eui-Baek [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Division of Bioresources and Biosciences, Faculty of Agriculture, Graduate school of Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Sung, Nak-Yun [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kwon, Sun-Kyu [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Graduate school of Food and Biotechnology, Korea University, Jochiwon 339-800 (Korea, Republic of); Song, Beom-Seok; Kim, Jae-Hun; Choi, Jong-il [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Hwang, Han-Joon [Graduate school of Food and Biotechnology, Korea University, Jochiwon 339-800 (Korea, Republic of); Byun, Myung-Woo [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Lee, Ju-Woon [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

    2009-07-15

    The physicochemical properties of proteins can be altered by irradiation. But, it is rarely that the researches on the functional properties of irradiated proteins have been reported. Fibroin is a fibrous protein derived from silkworm Bombyx mori and has been suggested as a biomaterial for biomedical application. Therefore, fibroin was selected as a model protein and was examined with the irradiation effects on the cytotoxicity of fibroin on tumor cell. The cytotoxicity of fibroin against mouse melanoma cell (B16BL6) showed a significant increase dependent upon the increase of irradiation dose. And also, the splenocyte proliferation activities of fibroin were increased by gamma irradiation. In addition, the oral administration of irradiated fibroin significantly increased the inhibition rate of tumor growth in tumor-bearing mouse model. The reason might be due to the change of protein structure by gamma irradiation and is being studied. From these result, it could be concluded that the irradiated fibroin might be a potential candidate as a valuable product in food and medical industry.

  7. The PARP inhibitor PJ-34 sensitizes cells to UVA-induced phototoxicity by a PARP independent mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, Petra; Hegedűs, Csaba [Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen (Hungary); Salazar Ayestarán, Nerea; Juarranz, Ángeles [Department of Biology, Faculty of Sciences, Universidad Autónoma of Madrid, 28049-Madrid (Spain); Kövér, Katalin E. [Department of Inorganic and Analytical Chemistry, Faculty of Sciences, University of Debrecen, Debrecen (Hungary); Szabó, Éva [Department of Dermatology, Faculty of Medicine, University of Debrecen, Debrecen (Hungary); Virág, László, E-mail: lvirag@med.unideb.hu [Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen (Hungary); MTA-DE Cell Biology and Signaling Research Group, Debrecen (Hungary)

    2016-08-15

    Highlights: • PARP-1 is not a key regulator of photochemotherapy. • The PARP inhibitor PJ-34 sensitizes cells to UVA-induced phototoxicity by a PARP independent mechanism. • Photosensitization by PJ-34 is associated with increased ROS production and DNA damage. • Cells sensitized by PJ-34 undergo caspase-mediated apoptosis. - Abstract: A combination of a photosensitizer with light of matching wavelength is a common treatment modality in various diseases including psoriasis, atopic dermatitis and tumors. DNA damage and production of reactive oxygen intermediates may impact pathological cellular functions and viability. Here we set out to investigate the role of the nuclear DNA nick sensor enzyme poly(ADP-ribose) polymerase 1 in photochemical treatment (PCT)-induced tumor cell killing. We found that silencing PARP-1 or inhibition of its enzymatic activity with Veliparib had no significant effect on the viability of A431 cells exposed to 8-methoxypsoralen (8-MOP) and UVA (2.5 J/cm{sup 2}) indicating that PARP-1 is not likely to be a key player in either cell survival or cell death of PCT-exposed cells. Interestingly, however, another commonly used PARP inhibitor PJ-34 proved to be a photosensitizer with potency equal to 8-MOP. Irradiation of PJ-34 with UVA caused changes both in the UV absorption and in the 1H NMR spectra of the compound with the latter suggesting UVA-induced formation of tautomeric forms of the compound. Characterization of the photosensitizing effect revealed that PJ–34 + UVA triggers overproduction of reactive oxygen species, induces DNA damage, activation of caspase 3 and caspase 8 and internucleosomal DNA fragmentation. Cell death in this model could not be prevented by antioxidants (ascorbic acid, trolox, glutathione, gallotannin or cell permeable superoxide dismutase or catalase) but could be suppressed by inhibitors of caspase-3 and −8. In conclusion, PJ-34 is a photosensitizer and PJ–34 + UVA causes DNA damage and caspase

  8. The Effects of Gamma Irradiation on Growth Response of Rodent Tuber (Typhonium flagelliforme Lodd.) Mutant in In Vitro Culture

    OpenAIRE

    Sianipar, Nesti Fronika; WANTHO, ARIANDANA; RUSTIKAWATI; Maarisit, Wilmar

    2013-01-01

    Rodent tuber (Typhonium flagelliforme Lodd.) is an Indonesian native plant that potential as anticancer. Even though the potential use of bioactive compounds from T. flagelliforme is very high, its genetic variation in Indonesia is low. Gamma irradiation can be used to increase genetic variation. The objective of this research was to obtain the first generation mutants (M1) of T. flagelliforme resulting from gamma irradiation of normal mother plantlets with different plant height and number o...

  9. The effect of gamma irradiation on the biological properties of intervertebral disc allografts: in vitro and in vivo studies in a beagle model.

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    Yu Ding

    Full Text Available STUDY DESIGN: An animal experiment about intervertebral disc allograft. OBJECTIVE: To explore the feasibility to decellularize disc allografts treated by 6°Co Gamma Irradiation, and simultaneously, to assess the possibility to make use of the decellularized natural disc scaffold for disc degeneration biotherapy. SUMMARY OF BACKGROUND DATA: Studies of both animal and human disc allograft transplantation indicated that the disc allograft may serve as a scaffold to undertake the physiological responsibility of the segment. METHODS: Experiment in vitro: 48 discs of beagles were harvested and divided randomly into four groups including a control group and three irradiated groups. Immediate cell viability and biomechanical properties of the discs were checked and comparisons were made among these groups. Experiment in vivo: 24 beagles accepted single-level allografted disc treated with different doses of gamma irradiation. Plain X-rays and MRIs were taken before and after surgery. Then, the spinal columns were harvested en bloc from the sacrificed beagles and were examined morphologically. RESULTS: There were significant differences of both the annulus fibrosus and nucleus pulposus immediate cell viabilities among the various groups. There were no obvious differences of the biomechanical properties among the four groups. The disc height and range of motion decreased significantly in all groups as time went on. The observed indexes in irradiated groups were much smaller than those in the control group, but the indexes in 18-kGy group were larger than those in 25-kGy and 50-kGy groups. Both MRI and macroscopic findings showed that the segmental degeneration in the control and 18-kGy group was less severe than that in 25-kGy and 50-kGy groups. CONCLUSION: Gamma Irradiation can decellularize disc allograft successfully to provide natural scaffold for the study of degenerative disc disease therapy, and also can be used as an effective method to produce

  10. Intrapulpal temperature changes during root surface irradiation with dual-wavelength laser (2780 and 940 nm): in vitro study

    Science.gov (United States)

    Franzen, Rene; Rashidisangsary, Borna; Ozturan, Seda; Vanweersch, Leon; Gutknecht, Norbert

    2015-01-01

    The present study evaluated the intrapulpal thermal changes that occurred during the treatment of the root surfaces with a laser system emitting Er,Cr:YSGG 2780- and 940-nm diode laser irradiation in an alternating sequence. Thirty single-rooted human teeth were collected. The teeth were divided into three groups (n=10 each) and irradiated with Er,Cr:YSGG alone or combined with a 940-nm diode laser. To investigate the intrapulpal temperature changes, specimens were embedded in a resin block with a set of thermocouples introduced at different positions within the root canals. The first group was irradiated with only Er,Cr:YSGG (25 mJ, 50 Hz, 50 μs pulse duration, water and air spray); the second group was irradiated with Er,Cr:YSGG (same setting) and a 940-nm diode (2 W, chopped mode with 20% duty cycle); the third group was irradiated with Er,Cr:YSGG (same setting) and a diode (2 W, chopped mode with 50% duty cycle). During all irradiations, thermal changes were recorded in real time with thermocouples. While group 3 showed thermal rises on average of 1.68±0.98°C in the pulp chamber, groups 1 and 2 showed average temperature rises of root surface debridement without inducing intrapulpal thermal damage when using an appropriate water/air spray. All measured temperatures were considerably below the critical value of 5.6°C.

  11. Effects of blue light irradiation on dental enamel remineralization in vitro; Avaliacao dos efeitos promovidos pela radiacao azul na remineralizacao do esmalte dentario in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Ilka Tiemy

    2009-07-01

    This study aimed to investigate the effects of blue radiation on dental enamel remineralization. In addition, a methodology of analysis was developed to evaluate alterations of enamel mineral content by optical coherence tomography. Artificial lesions were formed in bovine dental enamel slabs by immersing the samples in under saturated acetate buffer (2 mL/mm{sup 2} e 6.25 mL/mm{sup 2}). The lesions were irradiated with blue LED (l=455{+-}20nm), with radiant power of 110 mW, irradiance of 1.4 W/cm{sup 2}, radiant exposure of 13.8 J/{sup c}m2 and exposure time of 10 s. Remineralization was induced by pH-cycling model during 8 days. Cross-sectional hardness and optical coherence tomography (OCT) were used to assess mineral changes after remineralization. Hardness data showed that non-irradiated enamel lesions presented higher mineral content than irradiated ones and this difference was more evident in lesions formed in higher solution volume. The analysis of OCT signal also demonstrated that the mineral content of non-irradiated group was higher than in irradiated one; however, no significant difference was observed. Furthermore, significant differences in OCT sign were detected between sound and demineralized enamel. Based on the results obtained in the present study it can be concluded that blue radiation caused an inhibition of enamel remineralization. The methodology adopted for OCT analysis allowed the quantification of enamel mineral loss; however, the remineralization process could not be evaluated by this technique. (author)

  12. Protective effects of polyvinylpyrrolidone-wrapped fullerene against intermittent ultraviolet-A irradiation-induced cell injury in HaCaT cells.

    Science.gov (United States)

    Saitoh, Yasukazu; Ohta, Hiroaki; Hyodo, Sayuri

    2016-10-01

    To identify compounds that suppress UV irradiation-induced oxidative stress in the skin, various types of antioxidants have been studied. Polyvinylpyrrolidone-entrapped fullerene (C60/PVP) is known as a powerful antioxidant that exerts a cytoprotective effect against UV irradiation-induced cell injury in human skin cells and skin models. However, the effects of the alternate attractive C60/PVP feature, persistent antioxidant ability, on cytoprotection have rarely been ascertained. In this study we therefore investigated the efficacies of C60/PVP using an intermittently repeated UVA irradiation model wherein human keratinocytes were repeatedly exposed to UVA five times every 1h and compared the cytoprotective effects with those provided by ascorbic acid-2-O-phosphate-disodium salt (APS) and α-tocopherol (α-Toc). Our results demonstrated that C60/PVP yielded prominent cytoprotective effects against intermittently repeated UVA irradiation-induced injuries in a dose-dependent manner and suppressed intracellular superoxide anion radical (O2(-)) generation both during and after the repeated UVA irradiation. Additionally, C60/PVP also repressed the intermittent UVA irradiation-induced apoptosis via suppression of chromatin condensation and caspase-3/7 activation. Furthermore, the observed cytoprotective effects were superior to the effects of the typical antioxidants APS and α-Toc. These data suggest that C60/PVP might function as a potent cosmetic antioxidant against the effects of repeated and prolonged UVA irradiation through its persistent antioxidative property. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. In Vitro Bactericidal Effects of 625, 525, and 425 nm Wavelength (Red, Green, and Blue) Light-Emitting Diode Irradiation

    Science.gov (United States)

    Kim, SangWoo; Kim, JiSun; Lim, WonBong; Jeon, SangMi; Kim, OkSu; Koh, Jeong-Tae; Kim, Chang-Su; Choi, HongRan

    2013-01-01

    Abstract Objective: The purpose of this study was to evaluate the relationship of 625, 525, and 425 nm wavelengths, providing average power output and effects on three common pathogenic bacteria. Background data: Ultraviolet (UV) light kills bacteria, but the bactericidal effects of UV may not be unique, as 425 nm produces a similar effect. The bactericidal effects of light-emitting diode (LED) wavelengths such as 625 and 525 nm have not been described. Before conducting clinical trials, the appropriate wavelength with reasonable dose and exposure time should be established. Materials and methods: The bactericidal effects of 625, 525, and 425 nm wavelength LED irradiation were investigated in vitro for the anaerobic bacterium Porphyromonas gingivalis and two aerobes (Staphylococcus aureus and Escherichia coli DH5α). Average power output was 6 mW/cm2 for 1 h. The bacteria were exposed to LED irradiation for 1, 2, 4, and 8 h (21.6, 43.2, 86.4, and 172.8 J/cm2, respectively). LED irradiation was performed during growth on agar and in broth. Control bacteria were incubated without LED irradiation. Bacterial growth was expressed in colony-forming units (CFU) and at an optical density at 600 nm in agar and broth. Results: The bactericidal effect of LED phototherapy depended upon wavelength, power density, bacterial viable number, and bacteria species. The bactericidal effect of 425 and 525 nm irradiation varied depending upon the bacterial inoculation, compared with unirradiated samples and samples irradiated with red light. Especially, P. gingivalis and E. coli DH5α were killed by 425 nm, and S. aureus growth was inhibited by 525 nm. However, the wavelength of 625 nm was not bactericidal for P. gingivalis, E. coli DH5α, or S. aureus. Conclusions: Irradiation at 625 nm light was not bactericidal to S. aureus, E. coli, and P. gingivalis, whereas wavelengths of 425 and 525 nm had bactericidal effects. S. aureus was also killed at 525

  14. The Effects of Gamma Irradiation on Growth Response of Rodent Tuber (Typhonium flagelliforme Lodd. Mutant in In Vitro Culture

    Directory of Open Access Journals (Sweden)

    NESTI FRONIKA SIANIPAR

    2013-06-01

    Full Text Available Rodent tuber (Typhonium flagelliforme Lodd. is an Indonesian native plant that potential as anticancer. Even though the potential use of bioactive compounds from T. flagelliforme is very high, its genetic variation in Indonesia is low. Gamma irradiation can be used to increase genetic variation. The objective of this research was to obtain the first generation mutants (M1 of T. flagelliforme resulting from gamma irradiation of normal mother plantlets with different plant height and number of shoots. T. flagelliforme was irradiated at the doses of 0, 10, 20, 30, 40, and 50 Gy. The percentage of plant death was then calculated to determine the Lethal Dose (LD 50. T. flagelliforme was then re-irradiated at LD50 dose to obtain M1 mutant. The plant height and number of shoots variation was observed after eight weeks of culture. The analysis of T. flagelliforme radiosensitivity resulted in LD50 at 25 Gy. Observation at six weeks after irradiation showed significant differences between the normal mother plant, 20 Gy mutants, and 25 Gy mutants with an average plant height of 9.57, 3.41, and 2.43 cm respectively, and the average number of shoots produced was 7.85, 6.03, and 5.00 shoots respectively. Irradiation at 20 and 25 Gy produced 49 and 37 mutant plantlets. This research showed that gamma irradiation at LD50 dose could generate plant height and number of shoots variation of M1 mutant plantlets that are different from normal mother plantlets.

  15. Higher frequencies of chromosomal aberrations in lymphocytes of children with acute lymphoblastic leukemia after in vitro gamma irradiation

    Directory of Open Access Journals (Sweden)

    A Ramyar

    2012-12-01

    Full Text Available Background: Acute lymphoblastic leukemia (ALL is the most common malignancy in childhood, characterized by excess lymphoblasts, and immature white blood cells that are continuously multiplying and overproducing in the bone marrow. The aim of this investigation was to measure the sensitivity of lymphocytes against gamma irradiation in patients with acute lymphoblastic leukemia, and also find out the effect of such irradiations in causing chromosomal abnormalities.Methods: In this investigation performed between April 2010 and July 2011, at the Department of Genetics, Cancer Institute of Iran, we studied the effects of gamma irradiation on the lymphocytes of 20 children with acute lymphoblastic leukemia. The lymphocytes of 30 healthy donors were used to establish as a normal response to gamma irradiation and seven age-matched ataxia telangiectasia patients were recruited as positive control. The chromosomal radiosensitivity was assessed with the G2- and the G0-assay. We compared the mean number of chromosomal abnormalities such as chromosome and chromatid breakages, chromosome and chromatid gaps, and chromatid exchanges in one-hundred metaphases of patients and control groups.Results: The frequency of chromosomal aberrations was statistically higher among patients with acute lymphoblastic leukemia than the normal controls (P<0.01. In total, 65% of the patients were sensitive to gamma irradiation, but the remaining 35% were similar to the normal controls. Patients with ataxia telangiectasia showed the highest sensitivity to gamma irradiation (P=0.001.Conclusion: Our results showed that a high percentage of patients with acute lymphoblastic leukemia were sensitive to irradiation, meaning that maximum care should be taken during their treatment to avoid unnecessary X-rays or radiotherapies.

  16. Successful Treatment with UVA 1 Laser of Non - Responder Vitiligo Patients

    Directory of Open Access Journals (Sweden)

    Torello Lotti

    2018-01-01

    Full Text Available The Authors discuss their experience in treating non-responder vitiligo patients with a UVA-1 laser. Laser Alba 355® is an innovative device of target UVA - 1 phototherapy. The present report suggests that UVA1 laser could be an applicable therapeutic option in patients with vitiligo, also for the ones who did not respond to the more conventional phototherapies.

  17. Impact of UVA on pruritus during UVA/B phototherapy of inflammatory skin diseases: a randomized double-blind study.

    Science.gov (United States)

    Maul, J-T; Kretschmer, L; Anzengruber, F; Pink, A; Murer, C; French, L E; Hofbauer, G F; Navarini, A A

    2017-07-01

    Narrowband (TL-01) UVB phototherapy (UVB nb) is effective in treating inflammatory skin disease. The addition of UVA is traditionally advocated to reduce pruritus, but lacks evidence for this recommendation. The aim of this study was to assess the effect of UVB nb and UVA phototherapy in combination compared against UVB nb monotherapy on pruritus, disease activity and quality of life. In this double-blind randomized clinical trial, 53 patients suffering from inflammatory skin diseases with pronounced itching (Visual Analogue Scale (VAS) for pruritus ≥5) were randomized into two treatment groups. One group received UVB nb (311 nm) phototherapy alone and another group received a combination of UVB nb and UVA (320-400 nm) phototherapy. UV therapy was performed three times per week over 16 weeks. Pruritus (VAS and 5-D itch score), disease activity and quality of life (Dermatology Life Quality Index, DLQI) were assessed at baseline and weeks 4, 8, 12 and 16. In both treatment groups, there was a reduction in pruritus scores, disease activity and DLQI. No difference in pruritus score, disease activity and quality of life could be detected between the group receiving UVB nb alone and those receiving UVB nb combined with UVA. Phototherapy with UVB nb alone, and UVB nb combined with UVA are equally effective in treating inflammatory skin disease and indifferent in reducing disease-associated pruritus. Given this non-inferiority for UVB nb monotherapy, the recommendation of adding UVA to UVB nb phototherapy for pruritic inflammatory skin disease should be abandoned. © 2016 European Academy of Dermatology and Venereology.

  18. UVA1 for diffuse cutaneous systemic sclerosis in a Fitzpatrick skin type VI patient: outcomes in the modified Rodnan skin score

    Directory of Open Access Journals (Sweden)

    Bárbara Roque Ferreira

    2017-04-01

    Full Text Available Introduction: Cutaneous sclerosis can lead to important mobility impairment. Ultraviolet (UV A1 phototherapy may improve skin sclerosis, although most of the studies have been with Caucasian patients. Material and Methods: A 44-year-old patient, Fitzpatrick skin type VI, was being followed up with the diagnosis of diffuse cutaneous systemic sclerosis. He had significant mobility impairment, especially of the right hand and arm. In 2015 he started UVA1 phototherapy daily, Monday until Friday (Waldmann® 7001 UVA cabin equipped with 40 Philips TL/10R lamps − spectral irradiation between 340 and 400 nm. The initial dose was 10 J/cm2, rapidly increased up to a steady dose of 35 J/cm2. Results: After 40 sessions of UVA1, active fingers flexion and abduction of the right arm significantly improved and the modified Rodnan skin score changed from 26 to 11. Conclusion: The modified Rodnan skin score is a practical and useful tool during the follow-up of patients with systemic sclerosis. UVA1 phototherapy improves cutaneous sclerosis, and the related mobility impairment, and a dose of 35 J/cm2 is effective, even in higher phototypes, having a good safety profile.

  19. Effect of UV-A radiation as an environmental stress on the development, longevity, and reproduction of the oriental armyworm, Mythimna separata (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Ali, Arif; Rashid, Muhammad Adnan; Huang, Qiu Ying; Lei, Chao-Liang

    2016-09-01

    The ultraviolet light (UV-A) range of 320-400 nm is widely used as light trap for insect pests. Present investigation was aimed to determine the effect of UV light-A radiation on development, adult longevity, reproduction, and development of F1 generation of Mythimna separata. Our results revealed that the mortality of the second instar larvae was higher than the third and fourth instar larvae after UV-A radiation. As the time of UV-A irradiation for pupae prolonged, the rate of adult emergence reduced. Along with the extension of radiation time decreased the longevity of adult females and males. However, the radiation exposure of 1 and 4 h/day increased fecundity of female adults, and a significant difference was observed in a 1 h/day group. The oviposition rates of female adults in all the treatments were significantly higher than the control. In addition, UV-A radiation treatments resulted in declined cumulative survival of F1 immature stages (eggs, larvae, and pupae). After exposure time of 4 and 7 h/day, the developmental periods of F1 larvae increased significantly, but no significant effects on F1 pupal period were recorded.

  20. Helium-Neon Laser Irradiation Promotes the Proliferation and Migration of Human Epidermal Stem Cells In Vitro: Proposed Mechanism for Enhanced Wound Re-epithelialization

    Science.gov (United States)

    Liao, Xuan; Xie, Guang-Hui; Cheng, Biao; Li, Sheng-Hong; Xie, Shan; Xiao, Li-Ling; Fu, Xiao-Bing

    2014-01-01

    Abstract Objective: The present study was conducted to investigate the effects of helium-neon (He-Ne) laser irradiation on the proliferation, migration, and differentiation of cultured human epidermal stem cells (ESCs). Background data: A He-Ne laser with a wavelength of 632.8 nm is known to have photobiological effects, and is widely used for accelerating wound healing; however, the cellular mechanisms involved have not been completely understood. Methods: The ESCs were prepared from human foreskin, and irradiated by using He-Ne laser at 632.8 nm with 2 J/cm2. The ESC proliferation, migration, and differentiation were examined by using XTT assay, scratch assay, and flow cytometry technology, respectively. The phosphorylation of extracellular signal-regulated kinases (ERK) was analyzed by using Western blotting. Results: He-Ne laser irradiation markedly promoted cell proliferation and migration accompanied by an increase in the phosphorylation of ERK, but did not significantly influence cell differentiation. Conclusion: Our data indicated that photostimulation with a He-Ne laser resulted in a significant increase in human ESC proliferation and migration in vitro, which might contribute, at least partially, to accelerated wound re-epithelialization by low-level laser therapy. PMID:24661127

  1. In vitro hemocompatibility of sulfonated polypropylene non-woven fabric prepared via a facile γ-ray pre-irradiation grafting method

    Science.gov (United States)

    Li, Rong; Wu, Guozhong; Ye, Yin

    2015-11-01

    Sulfonated polypropylene non-woven fabric (PPNWF) was successfully prepared via γ-ray pre-irradiation-induced graft polymerization of sodium styrenesulfonate (SSS) and acrylamide (AAm). The effect of pre-irradiation dose, reaction temperature, reaction time and concentration of binary monomer on the degree of grafting (DG) was studied. The chemical structure of the original and modified PPNWF materials were investigated by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) to confirm the successful introduction of sulfonated (sbnd SO3-) group. The wettability was examined via measurement of de-ionized water adsorption percentage, which demonstrated that the hydrophilicity of PPNWF was greatly enhanced after graft modification. A little amount of bovine serum albumin (BSA) adsorption and nearly no platelet adhesion on the surface of modified PPNWF and low hemolytic ratio of the modified PPNWF revealed that the sulfonated PPNWF exhibited good hemocompatibility. Besides, blood clotting time measurement indicated that the anticoagulant property of PPNWF was effectively enhanced via SSS modification. Consequently, the hydrophilicity, in vitro hemocompatibility and anticoagulant effect of PPNWF were significantly improved by γ-ray pre-irradiation-induced graft polymerization of SSS.

  2. Use of in vitro gas production technique to evaluate the effects of microwave irradiation on sorghum (Sorghum bicolor and wheat (Triticum sp. nutritive values and fermentation characteristics

    Directory of Open Access Journals (Sweden)

    Farhad Parnian

    2013-01-01

    Full Text Available Effects of microwave irradiation (900 W for 3, 5 and 7 min on the nutritive value of sorghum and wheat grains were evaluated by in vitro gas production technique. Gas volume was recorded at 2, 4, 6, 8, 12, 16, 24, 36, 48, 72 and 96 h of incubation and kinetics of gas production were estimated using model: GP = A exp {– exp [1 + (be/A (LAG – t]}. Cumulative gas production at 24 h was used for estimation of metabolizable energy, net energy for lactation, short chain fatty acids, digestible organic matter and microbial protein. For sorghum grain, microwave irradiation increased cumulative gas production for most times of incubation linearly. Microwave treatments for 5 and 7 min increased the A fraction linearly in both cereal grain, whereas the maximum rate of gas production (b decreased linearly only in wheat grain. Microwave treatments for 3, 5 and 7 min increased (P<0.05 metabolizable energy, net energy for lactation and short chain fatty acids content of sorghum grain, but not of wheat grain. It was concluded that microwave irradiation changed the gas production parameters resulting changed ruminal fermentation characteristics that can be considered in ration formulation.

  3. Dose- and time-dependent gene expression alterations in prostate and colon cancer cells after in vitro exposure to carbon ion and X-irradiation

    Science.gov (United States)

    Suetens, Annelies; Moreels, Marjan; Quintens, Roel; Soors, Els; Buset, Jasmine; Chiriotti, Sabina; Tabury, Kevin; Gregoire, Vincent; Baatout, Sarah

    2015-01-01

    Hadrontherapy is an advanced form of radiotherapy that uses beams of charged particles (such as protons and carbon ions). Compared with conventional radiotherapy, the main advantages of carbon ion therapy are the precise absorbed dose localization, along with an increased relative biological effectiveness (RBE). This high ballistic accuracy of particle beams deposits the maximal dose to the tumor, while damage to the surrounding healthy tissue is limited. Currently, hadrontherapy is being used for the treatment of specific types of cancer. Previous in vitro studies have shown that, under certain circumstances, exposure to charged particles may inhibit cell motility and migration. In the present study, we investigated the expression of four motility-related genes in prostate (PC3) and colon (Caco-2) cancer cell lines after exposure to different radiation types. Cells were irradiated with various absorbed doses (0, 0.5 and 2 Gy) of accelerated 13C-ions at the GANIL facility (Caen, France) or with X-rays. Clonogenic assays were performed to determine the RBE. RT-qPCR analysis showed dose- and time-dependent changes in the expression of CCDC88A, FN1, MYH9 and ROCK1 in both cell lines. However, whereas in PC3 cells the response to carbon ion irradiation was enhanced compared with X-irradiation, the effect was the opposite in Caco-2 cells, indicating cell-type–specific responses to the different radiation types. PMID:25190155

  4. Helium-neon laser irradiation promotes the proliferation and migration of human epidermal stem cells in vitro: proposed mechanism for enhanced wound re-epithelialization.

    Science.gov (United States)

    Liao, Xuan; Xie, Guang-Hui; Liu, Hong-Wei; Cheng, Biao; Li, Sheng-Hong; Xie, Shan; Xiao, Li-Ling; Fu, Xiao-Bing

    2014-04-01

    The present study was conducted to investigate the effects of helium-neon (He-Ne) laser irradiation on the proliferation, migration, and differentiation of cultured human epidermal stem cells (ESCs). A He-Ne laser with a wavelength of 632.8 nm is known to have photobiological effects, and is widely used for accelerating wound healing; however, the cellular mechanisms involved have not been completely understood. The ESCs were prepared from human foreskin, and irradiated by using He-Ne laser at 632.8 nm with 2 J/cm(2). The ESC proliferation, migration, and differentiation were examined by using XTT assay, scratch assay, and flow cytometry technology, respectively. The phosphorylation of extracellular signal-regulated kinases (ERK) was analyzed by using Western blotting. He-Ne laser irradiation markedly promoted cell proliferation and migration accompanied by an increase in the phosphorylation of ERK, but did not significantly influence cell differentiation. Our data indicated that photostimulation with a He-Ne laser resulted in a significant increase in human ESC proliferation and migration in vitro, which might contribute, at least partially, to accelerated wound re-epithelialization by low-level laser therapy.

  5. Assessment of Correlation between Chromosomal Radiosensitivity of Peripheral Blood Lymphocytes after In vitro Irradiation and Normal Tissue Side Effects for Cancer Patients Undergoing Radiotherapy.

    Science.gov (United States)

    Guogytė, Kamilė; Plieskienė, Aista; Ladygienė, Rima; Vaisiūnas, Žygimantas; Sevriukova, Olga; Janušonis, Vinsas; Žiliukas, Julius

    2017-01-01

    Patients receiving identical radiation treatments experience different effects, from undetectable to severe, on normal tissues. A crucial factor of radiotherapy related side effects is individual radiosensitivity. It is difficult to spare surrounding normal tissues delivering radiation to cancer cells during radiotherapy. Therefore, it may be useful to develop a simple routine cytogenetic assay which would allow the screening of a large number of individuals for radiosensitivity optimizing tumor control rates and minimizing severe radiotherapy effects with possibility to predict risk level for developing more severe early normal tissue adverse events after irradiation. This study was conducted to assess the correlation between in vitro radiosensitivity of peripheral blood lymphocytes from cancer patients who are undergoing radiotherapy using the cytokinesis-block micronucleus (CBMN), G2 chromosomal radiosensitivity assays, and normal tissue acute side effects. The CBMN and G2 chromosomal radiosensitivity assays were performed on blood samples taken from cancer patients before radiotherapy, after first fractionation, and after radiotherapy. Acute normal tissue reactions were graded according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer. This study suggests that there is a correlation between higher frequency of micronuclei after in vitro irradiation of blood samples and higher degree of normal tissue reactions. In addition, higher number of chromatid breaks was observed in patients with more severe normal tissue reactions. This pilot study included only 5 cancer patients, and therefore, further studies with a bigger cohort are required to identify radiosensitive patients.

  6. Ultraviolet light-emitting diode irradiation-induced cell death in HL-60 human leukemia cells in vitro

    Science.gov (United States)

    XIE, DONG; SUN, YAN; WANG, LINGZHEN; LI, XIAOLING; ZANG, CHUANNONG; ZHI, YUNLAI; SUN, LIRONG

    2016-01-01

    Ultraviolet (UV) radiation is considered to be a potent cell-damaging agent in various cell lineages; however, the effect of UV light-emitting diode (LED) irradiation on human cells remains unclear. The aim of the present study was to examine the effect of UV LED irradiation emitting at 280 nm on cultured HL-60 human leukemia cells, and to explore the underlying mechanisms. HL-60 cells were irradiated with UV LED (8, 15, 30 and 60 J/m2) and incubated for 2 h after irradiation. The rates of cell proliferation and apoptosis, the cell cycle profiles and the mRNA expression of B-cell lymphoma 2 (Bcl-2) were detected using cell counting kit-8, multicaspase assays, propidium iodide staining and reverse transcription-quantitative polymerase chain reaction, respectively. The results showed that UV LED irradiation (8–60 J/m2) inhibited the proliferation of HL-60 cells in a dose-dependent manner. UV LED at 8–30 J/m2 induced dose-dependent apoptosis and G0/G1 cell cycle arrest, and inhibited the expression of Bcl-2 mRNA, while UV LED at 60 J/m2 induced necrosis. In conclusion, 280 nm UV LED irradiation inhibits proliferation and induces apoptosis and necrosis in cultured HL-60 cells. In addition, the cell cycle arrest at the G0/G1 phase and the downregulation of Bcl-2 mRNA expression were shown to be involved in UV LED-induced apoptosis. PMID:26820261

  7. Evaluation of thermal damage in dental implants after irradiation with 980nm diode laser. An in vitro study

    Directory of Open Access Journals (Sweden)

    Carlo Cafiero

    2016-12-01

    Full Text Available Purpose: The aim of this study was to analyze the thermal damage in dental implants after irradiations with a 980nm diode laser, normally used for the decontamination. Material and Methods: Five Titanium Plasma Sprayed dental implants were irradiated with a 980nm diode laser at different parameters. Temperature increase on implant surface was evaluated by a Mid-Wavelength Infrared thermal-camera (Merlin®, FLIR, USA. Temperature increase (ΔT was compared to environmental temperature (27°C and recorded in three points: “A” (laser spot, “B” (3mm apically to the laser spot and “C” (2mm horizontally to the laser spot. Finally, a morphological evaluation at optical stereomicroscopy was performed. Results: When 0.6W power was applied, a moderate increase of temperature in point A (5.5°C-15.0°C, a slight increase in point B (0.1°C-6.2°C and point C (0.1°C-5.7°C, were registered after 30” of irradiation. In the samples treated at 6W, in “point A” an impressive ΔT increase was immediately recorded (over 70°C. In “point B” was recorded a slight ΔT after 2 sec. irradiation (range 2.3°C-6.0°C, a moderate ΔT after 4 sec. irradiation (16.4°C and a consistent ΔT after 8-10 sec. irradiation (range 36.6°C-46.2°C. In “point C” ΔT values were very similar to those collected in “point B”. Optical stereomicroscopy examination at a magnification of 32x did not show any surface alteration or damage after whichever laser irradiation independently from irradiation time and power output . Conclusions: 980nm diode laser, used at controlled parameters, can be used in the decontamination of dental implants, without causing any thermal damage or increase.

  8. Derivation and validation of a universal vital assessment (UVA) score

    DEFF Research Database (Denmark)

    Moore, Christopher C; Hazard, Riley; Saulters, Kacie J

    2017-01-01

    BACKGROUND: Critical illness is a leading cause of morbidity and mortality in sub-Saharan Africa (SSA). Identifying patients with the highest risk of death could help with resource allocation and clinical decision making. Accordingly, we derived and validated a universal vital assessment (UVA...

  9. In vitro hemocompatibility of sulfonated polypropylene non-woven fabric prepared via a facile γ-ray pre-irradiation grafting method

    Energy Technology Data Exchange (ETDEWEB)

    Li, Rong [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Wu, Guozhong [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); School of Physical Science and Technology, ShanghaiTech University, Shanghai 200031 (China); Ye, Yin, E-mail: yeyin@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2015-11-30

    Graphical abstract: - Highlights: • Sulfonated PP{sub NWF} was successfully fabricated via γ-ray pre-irradiation-induced graft polymerization of SSS method with the aid of AAm. • Compared with the pristine PP{sub NWF}, the sulfonated PP{sub NWF} material presented outstanding hydrophilicity. • The sulfonated PP{sub NWF} exhibited good hemocompatibility. - Abstract: Sulfonated polypropylene non-woven fabric (PP{sub NWF}) was successfully prepared via γ-ray pre-irradiation-induced graft polymerization of sodium styrenesulfonate (SSS) and acrylamide (AAm). The effect of pre-irradiation dose, reaction temperature, reaction time and concentration of binary monomer on the degree of grafting (DG) was studied. The chemical structure of the original and modified PP{sub NWF} materials were investigated by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) to confirm the successful introduction of sulfonated (−SO{sub 3}{sup −}) group. The wettability was examined via measurement of de-ionized water adsorption percentage, which demonstrated that the hydrophilicity of PP{sub NWF} was greatly enhanced after graft modification. A little amount of bovine serum albumin (BSA) adsorption and nearly no platelet adhesion on the surface of modified PP{sub NWF} and low hemolytic ratio of the modified PP{sub NWF} revealed that the sulfonated PP{sub NWF} exhibited good hemocompatibility. Besides, blood clotting time measurement indicated that the anticoagulant property of PP{sub NWF} was effectively enhanced via SSS modification. Consequently, the hydrophilicity, in vitro hemocompatibility and anticoagulant effect of PP{sub NWF} were significantly improved by γ-ray pre-irradiation-induced graft polymerization of SSS.

  10. Determination of the antioxidant capacity of an antioxidant combination using the fluoroscan assay in vitro and visualization of its effects using histological methods.

    Science.gov (United States)

    El Hindi, Tarek; Ehlers, Gabriele; Demchuk, Maria; Pfitzner, Inka

    2004-11-01

    The effects of a well-defined combination of antioxidants on oxidative stress were investigated in vitro using classical techniques together and its protective effects against UV damage were investigated using a newly developed skin model. After determining the cytotoxic potential of the combination, its quenching effect on the oxidative stress induced by hydrogen peroxide was quantified by a nonfluorescent (C-H2DCF-DA/AM)/fluorescent (C-DCF) dye system using the fluoroscan assay. Two different skin models consisting of normal human skin fibroblasts and the keratinocyte cell line HaCaT were developed and subsequently used to visualize the protective effects of the combination against UVA damage. No evidence of any cytotoxic potential of the combination could be seen. Supplementation of human skin fibroblasts demonstrated a clear, dose-dependent enhancement of the antioxidative capacity of these cells. Histological findings confirmed the beneficial effects of the antioxidants present in the combination in the skin models used. Supplementation induced morphological changes leading to a thicker epidermal layer providing evidence of the positive effects of the treatment on the viability of the keratinocytes after UVA irradiation. This in vitro study provided convincing evidence of the combined antioxidative action of alpha-tocopherol, beta-carotene, tomato extract, grape seed extract, ascorbic acid and selenium yeast, and indicated a potential beneficial action of the combination against oxidative stress caused by external oxidative stress factors such as UV irradiation.

  11. Proteomic identification of cathepsin B and nucleophosmin as novel UVA-targets in human skin fibroblasts.

    Science.gov (United States)

    Lamore, Sarah D; Qiao, Shuxi; Horn, David; Wondrak, Georg T

    2010-01-01

    Solar UVA exposure plays a causative role in skin photoaging and photocarcinogenesis. Here, we describe the proteomic identification of novel UVA-targets in human dermal fibroblasts following a two-dimensional-difference-gel-electrophoresis (2D-DIGE) approach. Fibroblasts were exposed to noncytotoxic doses of UVA or left untreated, and total protein extracts underwent CyDye-labeling followed by 2D-DIGE/mass-spectrometric identification of differentially expressed proteins, confirmed independently by immunodetection. The protein displaying the most pronounced UVA-induced upregulation was identified as the nucleolar protein nucleophosmin. The protein undergoing the most pronounced UVA-induced downregulation was identified as cathepsin B, a lysosomal cysteine-protease displaying loss of enzymatic activity and altered maturation after cellular UVA exposure. Extensive lysosomal accumulation of lipofuscin-like autofluorescence and osmiophilic material occurred in UVA-exposed fibroblasts as detected by confocal fluorescence microscopy and transmission electron microscopy, respectively. Array analysis indicated UVA-induced upregulation of oxidative stress response gene expression, and UVA-induced loss of cathepsin B enzymatic activity in fibroblasts was suppressed by antioxidant intervention. Pharmacological cathepsin B inhibition using CA074Me mimicked UVA-induced accumulation of lysosomal autofluorescence and deficient cathepsin B maturation. Taken together, these data support the hypothesis that cathepsin B is a crucial target of UVA-induced photo-oxidative stress causatively involved in dermal photodamage through the impairment of lysosomal removal of lipofuscin. © 2010 The Authors. Journal Compilation. The American Society of Photobiology.

  12. Visible light is a better co-inducer of apoptosis for curcumin-treated human melanoma cells than UVA.

    Science.gov (United States)

    Buss, Stephan; Dobra, Jadranka; Goerg, Kerstin; Hoffmann, Stephanie; Kippenberger, Stefan; Kaufmann, Roland; Hofmann, Matthias; Bernd, August

    2013-01-01

    Curcumin attracts worldwide scientific interest due to its anti-proliferative and apoptosis inducing effects on different tumor cells at concentrations ranging from 10 to 150 µM (3.7-55 µg/ml). Unfortunately, because of a low oral bioavailability, only low and pharmacologically ineffective serum levels are achievable. In this study, an alternative treatment concept consisting of low concentration curcumin (0.2-5 µg/ml) and irradiation with UVA or visible light (VL) has been tested. The experimental results show clearly that this treatment decreases the proliferation and the viability of human melanoma cells while the cell membrane integrity remains intact. We identified the onset of apoptosis characterized by typical markers such as active caspases 8, 9 and 3 as well as DNA fragmentation accompanied by the loss of cell adhesion. The mitochondrial apoptosis signaling pathway is predominant due to an early activation of caspase-9. The present data indicate a higher efficacy of a combination of curcumin and VL than curcumin and UVA. Reduced effects as a result of light absorption by heavily pigmented skin are unlikely if VL is used. These results indicate that a combination of curcumin and light irradiation may be a useful additional therapy in the treatment of malignant disease.

  13. Visible light is a better co-inducer of apoptosis for curcumin-treated human melanoma cells than UVA.

    Directory of Open Access Journals (Sweden)

    Stephan Buss

    Full Text Available Curcumin attracts worldwide scientific interest due to its anti-proliferative and apoptosis inducing effects on different tumor cells at concentrations ranging from 10 to 150 µM (3.7-55 µg/ml. Unfortunately, because of a low oral bioavailability, only low and pharmacologically ineffective serum levels are achievable. In this study, an alternative treatment concept consisting of low concentration curcumin (0.2-5 µg/ml and irradiation with UVA or visible light (VL has been tested. The experimental results show clearly that this treatment decreases the proliferation and the viability of human melanoma cells while the cell membrane integrity remains intact. We identified the onset of apoptosis characterized by typical markers such as active caspases 8, 9 and 3 as well as DNA fragmentation accompanied by the loss of cell adhesion. The mitochondrial apoptosis signaling pathway is predominant due to an early activation of caspase-9. The present data indicate a higher efficacy of a combination of curcumin and VL than curcumin and UVA. Reduced effects as a result of light absorption by heavily pigmented skin are unlikely if VL is used. These results indicate that a combination of curcumin and light irradiation may be a useful additional therapy in the treatment of malignant disease.

  14. Repair of the three main types of bipyrimidine DNA photoproducts in human keratinocytes exposed to UVB and UVA radiations.

    Science.gov (United States)

    Courdavault, Sophie; Baudouin, Caroline; Charveron, Marie; Canguilhem, Bruno; Favier, Alain; Cadet, Jean; Douki, Thierry

    2005-07-12

    Induction of DNA damage by solar UV radiation is a key event in the development of skin cancers. Bipyrimidine photoproducts, including cyclobutane pyrimidine dimers (CPDs), (6-4) photoproducts (64 PPs) and their Dewar valence isomers, have been identified as major UV-induced DNA lesions. In order to identify the predominant and most persistent lesions, we studied the repair of the three types of photolesions in primary cultures of human keratinocytes. Specific and quantitative data were obtained using HPLC associated with tandem mass spectrometry. As shown in other cell types, 64 PPs are removed from UVB-irradiated keratinocytes much more efficiently than CPDs. In contrast, CPDs are still present in high amounts when cells recover their proliferation capacities after cell cycle arrest and elimination of a part of the population by apoptosis. The predominance of CPDs is still maintained when keratinocytes are exposed to a combination of UVB and UVA. Under these conditions, 64 PPs are converted into their Dewar valence isomers that are as efficiently repaired as their (6-4) precursors. Exposure of cells to pure UVA radiation generates thymine cyclobutane dimers that are slightly less efficiently repaired than CPDs produced upon UVB irradiation. Altogether, our results show that CPDs are the most frequent and the less efficiently repaired bipyrimidine photoproducts irrespectively of the applied UV treatment.

  15. UVA Photoirradiation of Oxygenated Benz[a]anthracene and 3-Methylcholanthene - Generation of Singlet Oxygen and Induction of Lipid Peroxidation

    Directory of Open Access Journals (Sweden)

    Diógenes Herreño Sáenz

    2008-03-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs are widespread genotoxic environmental pollutants and potentially pose a health risk to humans. Although the biological and toxicological activities, including metabolism, mutagenicity, and carcinogenicity, of PAHs have been thoroughly studied, their phototoxicity and photo-induced biological activity have not been well examined. We have long been interested in phototoxicity of PAHs and their derivatives induced by irradiation with UV light. In this paper we report the photoirradiation of a series of oxygenated benz[a]anthracene (BA and 3-methylcholanthene (3-MC by UVA light in the presence of a lipid, methyl linoleate. The studied PAHs include 2-hydroxy-BA (2-OH-BA, 3-hydroxy-BA (3-OH-BA, 5-hydroxymethyl-BA (5-CH2OH-BA, 7-hydroxymethyl-BA (7-CH2OH-BA, 12-hydroxymethyl-BA (12-CH2OH-BA, 7-hydroxymethyl-12-methyl-BA (7-CH2OH-12-MBA, 5-formyl-BA (5-CHO-BA, BA 5,6-cis-dihydrodiol (BA 5,6-cis-diol, 1-hydroxy-3- methylcholanthene (1-OH-3-MC, 1-keto-3-methylcholanthene (1-keto-3-MC, and 3-MC 1,2-diol. The results indicate that upon photoirradiation by UVA at 7 and 21 J/cm2, respectively all these compounds induced lipid peroxidation and exhibited a relationship between the dose of the light and the level of lipid peroxidation induced. To determine whether or not photoirradiation of these compounds by UVA light produces ROS, an ESR spin-trap technique was employed to provide direct evidence. Photoirradiation of 3-keto-3-MC by UVA (at 389 nm in the presence of 2,2,6,6-tetramethylpiperidine (TEMP, a specific probe for singlet oxygen, resulted in the formation of TEMPO, indicating that singlet oxygen was generated. These overall results suggest that UVA photoirradiation of oxygenated BA and 3-methylcholanthrene generates singlet oxygen, one of the reactive oxygen species (ROS, which induce lipid peroxidation.

  16. In vitro study of the influence of alpha particles irradiation on the pre-neoplastic transformation of rat trachea epithelial cells; Etude in vitro de l'influence d'une irradiation par des particules alpha sur la transformation preneoplasique des cellules epitheliales de trachee de rat

    Energy Technology Data Exchange (ETDEWEB)

    Kugel, C.

    2001-12-15

    Intern contamination by actinide oxide inhalation is potentially one health hazard during the nuclear fuel fabrication process. The aerosol particles can induce pulmonary lesions, such as epithelial cancers in particular. Their toxicity is mainly due to radiotoxicity of {alpha} irradiation. The aim of this work was to contribute, by an in vitro model, to the study of the apparition of pre-neoplastic states on epithelial cells after high LET irradiation. Primary cultures of rat tracheal epithelial cells were used. Two rat strain cells, SD TR for Sprague Dawley rats and WF TR for Wistar Furth I Fischer F344 rats, were compared after exposure to a dose range from 0 to 5 Gy. Reproductive cell death, i.e. senescent death, seems to be the main lethal way induced by {alpha} and {gamma} irradiations. The nuclear volume of WF TR cells is higher than that of SD TR ones, explaining the higher {alpha} radiation-induced lethality of these cells. These WF TR cells are also much sensitive to dose rate and {alpha} particles energy. In the same manner, pre-neoplastic transformation rate of the cells seems to depend on the physical parameters of irradiation. But, it mainly varies as a function of cell radiosensitivity, that means cell death. In fact, the transformation rate of sensitive WF TR cells is lower than that of SD TR ones. In term of transformation for SD TR cells, dose-effect relationship fits to a linear and infra linear function after {alpha} irradiation, whereas the curve fits to linear and quadratic function after {gamma} irradiation. The Relative Biological Efficiency (RBE) of {alpha} particles for lethality and pre-neoplastic transformation were determined for several levels of dose. A constant value of about 3 was found for RBE of lethality whatever the {alpha} dose. By contrast, the RBE of transformation has a value of about 10 up to 0.5 Gy and gradually decreases at higher doses to reach a value of 1 at 5 Gy. Similar shapes of dose-effect relationship can be

  17. Apical microinfiltration evaluation of radicular channels irradiated with Er:YAG laser in vitro; Avaliacao da microinfiltracao apical de condutos radiculares irradiados in vitro com laser de Er:YAG

    Energy Technology Data Exchange (ETDEWEB)

    Sebrao, Catia Cilene Nass

    2003-07-01

    It was evaluated, in vitro, the adaptation of the filling material (Sealer 2S{sup R}) to the root channels dentine walls treated using the endodontic technique and prepared with the Er:YAG laser, by the technique of infiltration of methylene blue dye. Using scanning electronic microscopy, the morphologic alteration of the root channel dentine was observed for one sample per studied group. Also, an evaluation of the temperature increase in the external surface of the root during the irradiations was performed for two samples per group. For each group of samples, with eleven roots each, two sub-groups had been considered: the dry, irradiated after completely dry with absorbent cones of paper, and the humid, where a cone of absorbent paper was applied for two seconds in the root canal, leaving them lightly humidified. Considering the used energies for the irradiations, the groups are: G1, control (without irradiation), G2-dry (100 mJ-10 Hz), G2-humid (100 mJ-10 Hz), G3-dry (140 mJ-6 Hz), G3-humid (140 mJ-6 Hz), G4-dry (180 mJ-6 Hz), and G4-humid (180 mJ-6 Hz). The results had shown that apical microinfiltration did not exhibit significant difference among groups. The highest increase in temperature was observed for the dry groups, with the maximum variation of temperature of 6.5 deg C. Under the scanning electronic microscopy analysis, the humid groups had presented cleaner surfaces than the dry groups. The G4-humid group presented extensive regions of fusion and resolidification of the dentine. (author)

  18. [Temperature variation at the external root surface during Nd: YAG laser irradiation in the root canal in vitro].

    Science.gov (United States)

    Yuan-Gao, Li; Xiao, Wang; Kexian, Xie; Dan, Liu

    2014-10-01

    To assess the temperature variation of the root surface using Nd: YAG laser irradiation in the root canal with different power and to evaluate the safety of laser application on the periodontal region. Thirty extracted human teeth with single-roots were collected. The teeth were cross-sectioned in the cervical portion, standardizing the roots at a 12-mm length. The roots were used as specimen. The roots were radiographed in the buccal-lingual direction to measure the thickness of the proximal walls, by means of a digital radiographic system. The specimens were divided into three groups according to the laser potency (1.5, 3.0, and 4.5 W). Each group was subdivided into two subgroups according to laser frequency (15 and 30 Hz). With the Nd: YAG laser irradiation for 20 s, the temperature variation of the root surface was monitored by thermocouples located at different parts of the root external wall and recorded by digital thermometers. The groups irradiated with 4.5 W presented the greatest temperature variation (above 10°C), followed by 3.0 and 1.5 W. The temperatures were statistically different (P 0.05). The apical half of the root presented statistically higher temperature rises than the cervical half of the root (P temperature variation of the root surface was associated with laser power, irradiation time, and the thickness of dentin. Application of Nd: YAG laser in the root at 1.5 W for 20 s can safely be used in endodontic treatment.

  19. Different doses of low-level laser irradiation modulate the in vitro response of osteoblast-like cells

    Science.gov (United States)

    Incerti Parenti, Serena; Checchi, Luigi; Fini, Milena; Tschon, Matilde

    2014-10-01

    Because osteoblasts play a key role in bone remodeling and the influence of low-level laser therapy on this process is not clear, Saos-2 human osteoblast-like cells were irradiated by a gallium-aluminum-arsenide diode laser (915 nm) for 10, 48, 96, 193, and 482 s using doses 1, 5, 10, 20, and 50 J/cm2, respectively. A control group was not irradiated. Morphology, viability, and cytotoxicity analyses were carried out after 1 hr, 1 day, and 3 days. Deoxyribose nucleic acid (DNA) content and release of vascular endothelial growth factor (VEGF), receptor activator of nuclear factor kappa B ligand (RANKL), and osteoprotegerin (OPG) were evaluated. Viability was modulated by laser irradiation in a dose-dependent manner, with 10 J/cm2 inducing a biostimulatory response and 20 to 50 J/cm2 determining a bioinhibitory and cytotoxic effect. Accordingly, DNA content was generally increased for the 10 J/cm2 dose and decreased for the 50 J/cm2 dose. A rapid and transitory trend toward increased RANKL/OPG ratio and a tendency toward a delayed increase in VEGF release for doses of 1 to 10 J/cm2 was found. Further investigations using the biostimulatory dose of 10 J/cm2 emerged from this study are needed to establish the ideal treatment regimens in the laboratory as well as in clinical practice.

  20. Disinfection of surfaces by photocatalytic oxidation with titanium dioxide and UVA light.

    Science.gov (United States)

    Kühn, Klaus P; Chaberny, Iris F; Massholder, Karl; Stickler, Manfred; Benz, Volker W; Sonntag, Hans-Günther; Erdinger, Lothar

    2003-10-01

    Particularly in microbiological laboratories and areas in intensive medical use, regular and thorough disinfection of surfaces is required in order to reduce the numbers of bacteria and to prevent bacterial transmission. The conventional methods of disinfection with wiping are not effective in the longer term, cannot be standardized, are time- and staff-intensive and use aggressive chemicals. Disinfection with hard ultraviolet C (UVC) light is usually not satisfactory, as the depth of penetration is inadequate and there are occupational medicine risks. Photocatalytic oxidation on surfaces coated with titanium dioxide (TiO2) might offer a possible alternative. In the presence of water and oxygen, highly reactive OH-radicals are generated by TiO2 and mild ultraviolet A (UVA). These radicals are able to destroy bacteria, and may therefore be effective in reducing bacterial contamination. Direct irradiation with UVC however can produce areas of shadow in which bacteria are not inactivated. Using targeted light guidance and a light-guiding sheet (out of a UVA-transmittant, Plexiglas, for example), as in the method described in the present study, bacterial inactivation over the entire area is possible. The effectiveness of the method was demonstrated using bacteria relevant to hygiene such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecium. For these bacteria, a reduction efficiency (RE) more than 6log10 steps in 60 min was observed. Using Candida albicans, a RE of 2log10 steps in 60 min was seen. Light and scanning electron microscopic examinations suggest that the germ destruction achieved takes place through direct damage to cell walls caused by OH-radicals.

  1. Shear bond strength to enamel of primary teeth irradiated with varying Er:YAG laser energies and SEM examination of the surface morphology: an in vitro study.

    Science.gov (United States)

    Wanderley, Rosimeyri L; Monghini, Elisângela M; Pecora, Jesus D; Palma-Dibb, Regina G; Borsatto, Maria C

    2005-06-01

    This study aimed to assess in vitro the influence of Er:YAG laser energy on the shear bond strength of a total-etch adhesive system to lased enamel of primary teeth, and to observe by SEM the morphological appearance of laser-ablated enamel surfaces. For the SBS test, primary canines were assigned to four groups (n = 12): a control (G1) and three groups irradiated with different Er:YAG laser energies- 60 mJ/2 Hz (G2), 80 mJ/2 Hz (G3), and 100 mJ/2 Hz (G4). In all groups, enamel surfaces were acidetched, Single Bond was applied, and resin cylinders were fabricated from Z250 resin. Bond strength was tested in shear (0.5 mm/min). For morphological analysis, 21 specimens were irradiated using the same energies, with or without acid-etching, and observed by SEM. SBS means, in MPa, were: G1-14.28 (+/-3.24); G2-18.48 (+/-4.58); G3-17.82 (+/-4.38); G4-16.59 (+/-5.40). Overall, Er:YAG laser ablation of primary teeth enamel, prior to the adhesive protocol, influenced the shear bond strength. Bond strengths recorded after irradiation with energies of 60 and 80 mJ were statistically similar among them (p > 0.05), and both were superior to those yielded by the acid-etched control group (p primary teeth enamel prior to the placement of adhesive restorative systems.

  2. Rho inhibition by lovastatin affects apoptosis and DSB repair of primary human lung cells in vitro and lung tissue in vivo following fractionated irradiation

    Science.gov (United States)

    Ziegler, Verena; Henninger, Christian; Simiantonakis, Ioannis; Buchholzer, Marcel; Ahmadian, Mohammad Reza; Budach, Wilfried; Fritz, Gerhard

    2017-01-01

    Thoracic radiotherapy causes damage of normal lung tissue, which limits the cumulative radiation dose and, hence, confines the anticancer efficacy of radiotherapy and impacts the quality of life of tumor patients. Ras-homologous (Rho) small GTPases regulate multiple stress responses and cell death. Therefore, we investigated whether pharmacological targeting of Rho signaling by the HMG-CoA-reductase inhibitor lovastatin influences ionizing radiation (IR)-induced toxicity in primary human lung fibroblasts, lung epithelial and lung microvascular endothelial cells in vitro and subchronic mouse lung tissue damage following hypo-fractionated irradiation (4x4 Gy). The statin improved the repair of radiation-induced DNA double-strand breaks (DSBs) in all cell types and, moreover, protected lung endothelial cells from IR-induced caspase-dependent apoptosis, likely involving p53-regulated mechanisms. Under the in vivo situation, treatment with lovastatin or the Rac1-specific small molecule inhibitor EHT1864 attenuated the IR-induced increase in breathing frequency and reduced the percentage of γH2AX and 53BP1-positive cells. This indicates that inhibition of Rac1 signaling lowers IR-induced residual DNA damage by promoting DNA repair. Moreover, lovastatin and EHT1864 protected lung tissue from IR-triggered apoptosis and mitigated the IR-stimulated increase in regenerative proliferation. Our data document beneficial anti-apoptotic and genoprotective effects of pharmacological targeting of Rho signaling following hypo-fractionated irradiation of lung cells in vitro and in vivo. Rac1-targeting drugs might be particular useful for supportive care in radiation oncology and, moreover, applicable to improve the anticancer efficacy of radiotherapy by widening the therapeutic window of thoracic radiation exposure. PMID:28796249

  3. Chromosome Damage and Cell Proliferation Rates in In Vitro Irradiated Whole Blood as Markers of Late Radiation Toxicity After Radiation Therapy to the Prostate

    Energy Technology Data Exchange (ETDEWEB)

    Beaton, Lindsay A., E-mail: Lindsay.Beaton@hc-sc.gc.ca [Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, ON (Canada); Ferrarotto, Catherine; Marro, Leonora [Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, ON (Canada); Samiee, Sara; Malone, Shawn; Grimes, Scott; Malone, Kyle [The Ottawa Hospital, Ottawa Hospital Research Institute, University of Ottawa, 501 Smyth Rd, Ottawa, ON (Canada); Wilkins, Ruth C. [Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, ON (Canada)

    2013-04-01

    Purpose: In vitro irradiated blood samples from prostate cancer patients showing late normal tissue damage were examined for lymphocyte response by measuring chromosomal aberrations and proliferation rate. Methods and Materials: Patients were selected from a randomized trial evaluating the optimal timing of dose-escalated radiation and short-course androgen deprivation therapy. Of 438 patients, 3% experienced grade 3 late radiation proctitis and were considered to be radiosensitive. Blood samples were taken from 10 of these patients along with 20 matched samples from patients with grade 0 proctitis. The samples were irradiated at 6 Gy and, along with control samples, were analyzed for dicentric chromosomes and excess fragments per cell. Cells in first and second metaphase were also enumerated to determine the lymphocyte proliferation rate. Results: At 6 Gy, there were statistically significant differences between the radiosensitive and control cohorts for 3 endpoints: the mean number of dicentric chromosomes per cell (3.26 ± 0.31, 2.91 ± 0.32; P=.0258), the mean number of excess fragments per cell (2.27 ± 0.23, 1.43 ± 0.37; P<.0001), and the proportion of cells in second metaphase (0.27 ± 0.10, 0.46 ± 0.09; P=.0007). Conclusions: These results may be a valuable indicator for identifying radiosensitive patients and for tailoring radiation therapy.

  4. Chromosome damage and cell proliferation rates in in vitro irradiated whole blood as markers of late radiation toxicity after radiation therapy to the prostate.

    Science.gov (United States)

    Beaton, Lindsay A; Ferrarotto, Catherine; Marro, Leonora; Samiee, Sara; Malone, Shawn; Grimes, Scott; Malone, Kyle; Wilkins, Ruth C

    2013-04-01

    In vitro irradiated blood samples from prostate cancer patients showing late normal tissue damage were examined for lymphocyte response by measuring chromosomal aberrations and proliferation rate. Patients were selected from a randomized trial evaluating the optimal timing of dose-escalated radiation and short-course androgen deprivation therapy. Of 438 patients, 3% experienced grade 3 late radiation proctitis and were considered to be radiosensitive. Blood samples were taken from 10 of these patients along with 20 matched samples from patients with grade 0 proctitis. The samples were irradiated at 6 Gy and, along with control samples, were analyzed for dicentric chromosomes and excess fragments per cell. Cells in first and second metaphase were also enumerated to determine the lymphocyte proliferation rate. At 6 Gy, there were statistically significant differences between the radiosensitive and control cohorts for 3 endpoints: the mean number of dicentric chromosomes per cell (3.26 ± 0.31, 2.91 ± 0.32; P=.0258), the mean number of excess fragments per cell (2.27 ± 0.23, 1.43 ± 0.37; P<.0001), and the proportion of cells in second metaphase (0.27 ± 0.10, 0.46 ± 0.09; P=.0007). These results may be a valuable indicator for identifying radiosensitive patients and for tailoring radiation therapy. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  5. Comparative study between laser and conventional techniques for class V cavity preparation in gamma-irradiated teeth (in vitro study).

    Science.gov (United States)

    Rasmy, Amr H M; Harhash, Tarek A; Ghali, Rami M S; El Maghraby, Eman M F; El Rouby, Dalia H

    2017-01-01

    The purpose of this study was to compare laser with conventional techniques in class V cavity preparation in gamma-irradiated teeth. Forty extracted human teeth with no carious lesions were used for this study and were divided into two main groups: Group I (n = 20) was not subjected to gamma radiation (control) and Group II (n=20) was subjected to gamma radiation of 60 Gray. Standard class V preparation was performed in buccal and lingual sides of each tooth in both groups. Buccal surfaces were prepared by the Er,Cr:YSGG laser (Waterlase iPlus) 2780 nm, using the gold handpiece with MZ10 Tip in non-contact and the "H" mode, following parameters of cavity preparation - power 6 W, frequency 50 Hz, 90% water and 70% air, then shifting to surface treatment laser parameters - power 4.5 W, frequency 50 Hz, 80% water and 50% air. Lingual surfaces were prepared by the conventional high-speed turbine using round diamond bur. Teeth were then sectioned mesio-distally, resulting in 80 specimens: 40 of which were buccal laser-treated (20 control and 20 gamma-irradiated specimens) and 40 were lingual conventional high-speed bur specimens (20 control and 20 gamma-irradiated specimens). Microleakage analysis revealed higher scores in both gamma groups compared with control groups. Chi-square test revealed no significant difference between both control groups and gamma groups (p=1, 0.819, respectively). A significant difference was revealed between all 4 groups (p=0.00018). Both laser and conventional high-speed turbine bur show good bond strength in control (non-gamma) group, while microleakage is evident in gamma group, indicating that gamma radiation had a dramatic negative effect on the bond strength in both laser and bur-treated teeth.

  6. Comparative study between laser and conventional techniques for class V cavity preparation in gamma-irradiated teeth (in vitro study

    Directory of Open Access Journals (Sweden)

    Amr H. M. Rasmy

    Full Text Available Abstract Objective: The purpose of this study was to compare laser with conventional techniques in class V cavity preparation in gamma-irradiated teeth. Methods: Forty extracted human teeth with no carious lesions were used for this study and were divided into two main groups: Group I (n = 20 was not subjected to gamma radiation (control and Group II (n=20 was subjected to gamma radiation of 60 Gray. Standard class V preparation was performed in buccal and lingual sides of each tooth in both groups. Buccal surfaces were prepared by the Er,Cr:YSGG laser (Waterlase iPlus 2780 nm, using the gold handpiece with MZ10 Tip in non-contact and the “H” mode, following parameters of cavity preparation – power 6 W, frequency 50 Hz, 90% water and 70% air, then shifting to surface treatment laser parameters – power 4.5 W, frequency 50 Hz, 80% water and 50% air. Lingual surfaces were prepared by the conventional high-speed turbine using round diamond bur. Teeth were then sectioned mesio-distally, resulting in 80 specimens: 40 of which were buccal laser-treated (20 control and 20 gamma-irradiated specimens and 40 were lingual conventional high-speed bur specimens (20 control and 20 gamma-irradiated specimens. Results: Microleakage analysis revealed higher scores in both gamma groups compared with control groups. Chi-square test revealed no significant difference between both control groups and gamma groups (p=1, 0.819, respectively. A significant difference was revealed between all 4 groups (p=0.00018. Conclusion: Both laser and conventional high-speed turbine bur show good bond strength in control (non-gamma group, while microleakage is evident in gamma group, indicating that gamma radiation had a dramatic negative effect on the bond strength in both laser and bur-treated teeth.

  7. Antimicrobial susceptibility of photodynamic therapy (UVA/riboflavin against Staphylococcus aureus Suscetibilidade antimicrobiana da terapia fotodinâmica (UVA/riboflavina contra Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Renata Tiemi Kashiwabuchi

    2012-12-01

    Full Text Available PURPOSE: To assess S. aureus in vitro viability after the exposure to ultraviolet light A (UVA and riboflavin (B2. METHODS: Samples of S. aureus in 96 well plates (in triplicate were exposed to riboflavin (B2 and ultraviolet light A (365 nm wavelength at a power density of 3 mW/cm², 8 mm spot diameter, for 30 minutes. Control groups were prepared as well in triplicate: blank control, ultraviolet light A only, riboflavin only and dead bacteria Control. The bacterial viability was measured using fluorescent microscopy. In order to investigate the occurrence of "viable but non-culturable" microorganisms after treatment, the cell viability was also investigated by plate culture procedure onto a broth medium. Statistical analysis was performed using the triplicate values from each experimental condition. RESULTS: No difference was observed among the treatment group and the control samples (p=1. CONCLUSION: The combination of riboflavin 0.1% and ultraviolet light A at 365 nm did not exhibit antimicrobial activity against oxacillin susceptible S. aureus.OBJETIVO: Avaliar a viabilidade celular de S. aureus in vitro após a exposição de riboflavina (B2 e luz ultravioleta A (UVA. MÉTODOS: Amostras de S. aureus colocadas em uma placa de 96 poços (em triplicata foram expostas a riboflavina 0,1% (B2 e luz ultravioleta (comprimento de onda de 365 nm poder de 3 mW/cm², 8 mm de diâmetro, por 30 minutos. Grupos controles foram também preparados em triplicata: controle branco, somente luz ultravioleta A, somente riboflavina e controle morto. A viabilidade bacteriana foi analisada usando microscópio de fluorescência. Para investigar a ocorrência de micro-organismos "viáveis porem não cultiváveis" a viabilidade celular foi avaliada utilizando-se placas de meio de cultivo bacteriano. Analise estatística foi realizada utilizando-se os valores obtidos em triplicata de cada grupo experimental. RESULTADOS: Nenhuma diferença foi observada entre o grupo

  8. Ultraviolet-C Irradiation for Prevention of Central Venous Catheter Related Infections: An In-vitro Study

    Science.gov (United States)

    Dai, Tianhong; Tegos, George P.; St. Denis, Tyler G.; Anderson, Don; Sinofsky, Ed; Hamblin, Michael R.

    2010-01-01

    Central venous catheters (CVC) are widely used in the United States and are associated with 250,000 to 500,000 CVC-related infections in hospitals annually. We used a catheter made from ultraviolet-C (UVC) transmissive material to test whether delivery of UVC from the lumen would allow inactivation of microorganisms on the outer surface of CVC. When the catheter was exposed to UVC irradiation from a cold cathode fluorescent lamp (CCFL) inside the catheter lumen at a radiant exposure of 3.6 mJ/cm2, more than 6-log10 of drug-resistant Gram-positive bacteria adhered to the outer surface of the catheter were inactivated. Three to 7-log10 of drug-resistant Gram-negative bacteria and 2.8 log10 of fungi were inactivated at a radiant exposure of 11 mJ/cm2. UVC irradiation also offered a highly selective inactivation of bacteria over keratinocytes under exactly comparable conditions. After 11 mJ/cm2 UVC light had been delivered, over 6 log10 of bacteria were inactivated while the viability loss of the keratinocytes was only about 57%. PMID:21073470

  9. The effect of riboflavin/UVA collagen cross-linking therapy on the structure and hydrodynamic behaviour of the ungulate and rabbit corneal stroma.

    Directory of Open Access Journals (Sweden)

    Sally Hayes

    Full Text Available PURPOSE: To examine the effect of riboflavin/UVA corneal crosslinking on stromal ultrastructure and hydrodynamic behaviour. METHODS: One hundred and seventeen enucleated ungulate eyes (112 pig and 5 sheep and 3 pairs of rabbit eyes, with corneal epithelium removed, were divided into four treatment groups: Group 1 (28 pig, 2 sheep and 3 rabbits were untreated; Group 2 (24 pig were exposed to UVA light (3.04 mW/cm(2 for 30 minutes and Group 3 (29 pig and Group 4 (31 pig, 3 sheep and 3 rabbits had riboflavin eye drops applied to the corneal surface every 5 minutes for 35 minutes. Five minutes after the initial riboflavin instillation, the corneas in Group 4 experienced a 30 minute exposure to UVA light (3.04 mW/cm(2. X-ray scattering was used to obtain measurements of collagen interfibrillar spacing, spatial order, fibril diameter, D-periodicity and intermolecular spacing throughout the whole tissue thickness and as a function of tissue depth in the treated and untreated corneas. The effect of each treatment on the hydrodynamic behaviour of the cornea (its ability to swell in saline solution and its resistance to enzymatic digestion were assessed using in vitro laboratory techniques. RESULTS: Corneal thickness decreased significantly following riboflavin application (p<0.01 and also to a lesser extent after UVA exposure (p<0.05. With the exception of the spatial order factor, which was higher in Group 4 than Group 1 (p<0.01, all other measured collagen parameters were unaltered by cross-linking, even within the most anterior 300 microns of the cornea. The cross-linking treatment had no effect on the hydrodynamic behaviour of the cornea but did cause a significant increase in its resistance to enzymatic digestion. CONCLUSIONS: It seems likely that cross-links formed during riboflavin/UVA therapy occur predominantly at the collagen fibril surface and in the protein network surrounding the collagen.

  10. 'In vitro' study of the efficacy of diode laser and LED irradiation during dental bleaching; Estudo 'in vitro' da acao do LED e laser de diodo no clareamento dental

    Energy Technology Data Exchange (ETDEWEB)

    Barroso, Marcia Cristina da Silva

    2003-07-01

    This in vitro study evaluated the efficacy of LED and laser diode irradiation during the dental bleaching procedure, using two bleaching agents (Opalescence X-tra and HP Whiteness). The diode laser and the LED were operated in the continuous mode, with wavelength of 808 nm and 470 nm, respectively. The results of the irradiations were characterized with the CIELAB system calculating the L{sup *}a{sup *}b{sup *} values for the darkened and the bleached teeth (60 bovine incisors). This is to our knowledge the first time that light sources laser and LED are compared with respect to their whitening capability when applied to different agents. Significant differences in the chroma value are obtained for the two whitening agents and for the different light sources, too. Also, in terms of luminance, the combination of laser/ Whiteness HP showed significantly better results than when the same agent was used alone or in combination with LED. Best overall results are obtained with the combination of Whiteness HP and laser. (author)

  11. Long-term in vitro and in vivo effects of γ-irradiated BCG on innate and adaptive immunity.

    Science.gov (United States)

    Arts, Rob J W; Blok, Bastiaan A; Aaby, Peter; Joosten, Leo A B; de Jong, Dirk; van der Meer, Jos W M; Benn, Christine Stabell; van Crevel, Reinout; Netea, Mihai G

    2015-12-01

    BCG vaccination is associated with a reduced mortality from nonmycobacterial infections. This is likely to be mediated by a combination of innate-immune memory ("trained immunity") and heterologous effects on adaptive immunity. As such, BCG could be used to boost host immunity but not in immunocompromised hosts, as it is a live, attenuated vaccine. Therefore, we assessed whether killed γBCG has similar potentiating effects. In an in vitro model of trained immunity, human monocytes were incubated with γBCG for 24 h and restimulated after 6 d. Cytokine production and the role of pattern recognition receptors and histone methylation markers were assessed. The in vivo effects of γBCG vaccination were studied in a proof-of-principle trial in 15 healthy volunteers. γBCG induced trained immunity in vitro via the NOD2 receptor pathway and up-regulation of H3K4me3 histone methylation. However, these effects were less strong than those induced by live BCG. γBCG vaccination in volunteers had only minimal effects on innate immunity, whereas a significant increase in heterologous Th1/Th17 immunity was observed. Our results indicate that γBCG induces long-term training of innate immunity in vitro. In vivo, γBCG induces mainly heterologous effects on the adaptive-immune system, whereas effects on innate cytokine production are limited. © Society for Leukocyte Biology.

  12. New noninvasive approach assessing in vivo sun protection factor (SPF) using diffuse reflectance spectroscopy (DRS) and in vitro transmission.

    Science.gov (United States)

    Ruvolo Junior, Eduardo; Kollias, Nikiforos; Cole, Curtis

    2014-08-01

    In the past 56 years, many different in vitro methodologies have been developed and published to assess the sun protection factor (SPF) of products, but there is no method that has 1:1 correlation with in vivo measurements. Spectroscopic techniques have been used to noninvasively assess the UVA protection factor with good correlation to in vivo UVA-PF methodologies. To assess the SPF of sunscreen product by diffuse reflectance spectroscopy (DRS) technique, it is necessary to also determine the absorbance spectrum of the test material in the UVB portion of the spectrum (290-320 nm). However, because of the high absorbance characteristics of the stratum corneum and epidermis, the human skin does not remit enough UVB radiation to be used to measure the absorption spectrum of the applied product on skin. In this work, we present a new method combining the evaluation of the absolute UVA absorption spectrum, as measured by DRS with the spectral absorbance 'shape' of the UVB absorbance of the test material as determined with current in vitro thin film spectroscopy. The measurement of the in vivo UVA absorption spectrum involves the assessment of the remitted intensity of monochromatic UVA radiation (320-400 nm) before and after a sunscreen product was applied on skin using a spectrofluorimeter Fluorolog 3, FL3-22 (Yvon Horiba, Edison, NJ, USA). The probe geometry assures that light scattering products as well as colored products may be correctly assessed. This methodology has been extensively tested, validated, and reported in the literature. The in vitro absorption spectrum of the sunscreen samples and polyvinyl chloride (PVC) films 'surrogate' sunscreen standards were measured using Labsphere® UV-2000S (Labsphere, North Sutton, NH, USA). Sunscreens samples were tested using PMMA Helioplates (Helioscience, Marseille, France) as substrates. The UVB absorbance spectrum (Labsphere) is 'attached' to the UVA absorbance spectrum (diffuse reflectance) with the UVB

  13. Low concentrations of curcumin induce growth arrest and apoptosis in skin keratinocytes only in combination with UVA or visible light.

    Science.gov (United States)

    Dujic, Jadranka; Kippenberger, Stefan; Hoffmann, Stephanie; Ramirez-Bosca, Ana; Miquel, Jaime; Diaz-Alperi, Joquin; Bereiter-Hahn, Jürgen; Kaufmann, Roland; Bernd, August

    2007-08-01

    It is well known that curcumin, a dietary pigment from the plant Curcuma longa, inhibits cell proliferation and induces apoptosis in different cell lines at concentrations ranging from 10 to 150 microM (3.7-55 microg/ml). In this study, we show that curcumin at low concentrations (0.2-1 microg/ml) also has an antiproliferative effect when applied in combination with UVA or visible light. We demonstrate that such a treatment induces apoptosis in human skin keratinocytes represented by the increase of fragmented cell nuclei, release of cytochrome c from mitochondria, activation of caspases-9 and -8, and inhibition of NF-kappaB activity. Furthermore, inhibition of extracellular regulated kinases 1/2 and protein kinase B was found to ensure the proapoptotic effect. Additionally, the EGFR, an upstream regulator of both kinases, was inhibited indicating that apoptosis is induced by blocking survival- and proliferation-associated signal cascades at the receptor level. In summary, these findings suggest a new therapeutic concept for the treatment of hyperproliferative diseases by combining topical curcumin with UVA or visible light. In particular, the latter avoids the use of carcinogenic irradiation that is part of regular phototherapy.

  14. Protective effect of Opuntia ficus-indica L. cladodes against UVA-induced oxidative stress in normal human keratinocytes.

    Science.gov (United States)

    Petruk, Ganna; Di Lorenzo, Flaviana; Imbimbo, Paola; Silipo, Alba; Bonina, Andrea; Rizza, Luisa; Piccoli, Renata; Monti, Daria Maria; Lanzetta, Rosa

    2017-12-15

    Opuntia ficus-indica L. is known for its beneficial effects on human health, but still little is known on cladodes as a potent source of antioxidants. Here, a direct, economic and safe method was set up to obtain water extracts from Opuntia ficus-indica cladodes rich in antioxidant compounds. When human keratinocytes were pre-treated with the extract before being exposed to UVA radiations, a clear protective effect against UVA-induced stress was evidenced, as indicated by the inhibition of stress-induced processes, such as free radicals production, lipid peroxidation and GSH depletion. Moreover, a clear protective effect against apoptosis in pre-treated irradiated cells was evidenced. We found that eucomic and piscidic acids were responsible for the anti-oxidative stress action of cladode extract. In conclusion, a bioactive, safe, low-cost and high value-added extract from Opuntia cladodes was obtained to be used for skin health/protection. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Long-term in vitro and in vivo effects of γ-irradiated BCG on innate and adaptive immunity

    DEFF Research Database (Denmark)

    Arts, Rob J W; Blok, Bastiaan A; Aaby, Peter

    2015-01-01

    BCG vaccination is associated with a reduced mortality from nonmycobacterial infections. This is likely to be mediated by a combination of innate-immune memory ("trained immunity") and heterologous effects on adaptive immunity. As such, BCG could be used to boost host immunity but not in immunoco......BCG vaccination is associated with a reduced mortality from nonmycobacterial infections. This is likely to be mediated by a combination of innate-immune memory ("trained immunity") and heterologous effects on adaptive immunity. As such, BCG could be used to boost host immunity...... but not in immunocompromised hosts, as it is a live, attenuated vaccine. Therefore, we assessed whether killed γBCG has similar potentiating effects. In an in vitro model of trained immunity, human monocytes were incubated with γBCG for 24 h and restimulated after 6 d. Cytokine production and the role of pattern recognition...... receptors and histone methylation markers were assessed. The in vivo effects of γBCG vaccination were studied in a proof-of-principle trial in 15 healthy volunteers. γBCG induced trained immunity in vitro via the NOD2 receptor pathway and up-regulation of H3K4me3 histone methylation. However, these effects...

  16. Identification of influential events concerning the Antarctic ozone hole over southern Brazil and the biological effects induced by UVB and UVA radiation in an endemic treefrog species.

    Science.gov (United States)

    Passaglia Schuch, André; Dos Santos, Mauricio Beux; Mendes Lipinski, Victor; Vaz Peres, Lucas; Dos Santos, Caroline Peripolli; Zanini Cechin, Sonia; Jorge Schuch, Nelson; Kirsh Pinheiro, Damaris; da Silva Loreto, Elgion Lúcio

    2015-08-01

    The increased incidence of solar ultraviolet radiation (UV) due to ozone depletion has been affecting both terrestrial and aquatic ecosystems and it may help to explain the enigmatic decline of amphibian populations in specific localities. In this work, influential events concerning the Antarctic ozone hole were identified in a dataset containing 35 years of ozone measurements over southern Brazil. The effects of environmental doses of UVB and UVA radiation were addressed on the morphology and development of Hypsiboas pulchellus tadpole (Anura: Hylidae), as well as on the induction of malformation after the conclusion of metamorphosis. These analyzes were complemented by the detection of micronucleus formation in blood cells. 72 ozone depletion events were identified from 1979 to 2013. Surprisingly, their yearly frequency increased three-fold during the last 17 years. The results clearly show that H. pulchellus tadpole are much more sensitive to UVB than UVA light, which reduces their survival and developmental rates. Additionally, the rates of micronucleus formation by UVB were considerably higher compared to UVA even after the activation of photolyases enzymes by a further photoreactivation treatment. Consequently, a higher occurrence of malformation was observed in UVB-irradiated individuals. These results demonstrate the severe genotoxic impact of UVB radiation on this treefrog species and its importance for further studies aimed to assess the impact of the increased levels of solar UVB radiation on declining species of the Hylidae family. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Cytostatic action of aspirin and its effect on mitomycin C activity. A study in vitro under irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kammerer, Cornelia; Getoff, Nikola E-mail: nikola.getoff@univie.ac.at

    2001-04-01

    Experiments in vitro using E. coli bacteria (AB 1157) proved that aspirin possesses a cytostatic ability under various experimental condition (pH=7.4) in airfree, aerated as well as in media containing N{sub 2}O (converting e{sub aq}{sup -} into OH- radicals). In the last case the highest effect of aspirin was observed. The combination of aspirin with the well-known cytostaticum, mitomycin C (MMC) leads in airfree as well as in aerated media to a significant decrease of the MMC activity. However, the mixture of aspirin and MMC in the presence of N{sub 2}O causes a synergistic effect, resulting in an enhancement of the MMC activity by a factor of 1.5. Probable reaction steps are presented and discussed. Using the pulse radiolysis method the rate constants for the reactions of e{sub aq}{sup -}, H and OH- species with aspirin were also determined.

  18. Evaluation in vitro of effects of Er:YAG and Nd:YAG lasers irradiation on root canal wall, by stereoscopy, scanning electron micrography and thermographic camera; Avaliacao in vitro dos efeitos da irradiacao laser de Er:YAG e Nd:YAG na parede dentinaria do canal radicular, sob observacao do estereoscopio, da micrografia eletronica e da camera termografica

    Energy Technology Data Exchange (ETDEWEB)

    Goya, Claudia

    2001-07-01

    This study was carried out to evaluate in vitro the effects of Nd:YAG laser and Er:YAG laser irradiation in the root canal wall by SEM, evaluating the apical leakage and the temperature changes during the laser irradiation. Seventy four extracted human teeth were used, they were instrumented and divided into seven groups of 10 teeth each. The teeth were evaluated through stereoscopy, by SEM, and with the thermographic camera. The Nd:YAG laser irradiation parameters were 100 mJ/p, 15 Hz, and Er:YAG laser were 160 mJ/p and 10 Hz, the irradiation was 4 times at 2 mm/sec speed, with 20 sec interval. The apical leakage was not observed in the teeth irradiated by Nd:YAG laser alone or in association with Er:YAG laser. However in the teeth irradiated only by the Er:YAG laser we observed a little leakage. By SEM observation the Nd:YAG laser irradiation showed melting and recrystallization in the dentin surface closing dentinal tubules, and in the samples irradiated by Er:Y AG laser a clean surface, opened dentinal tubules, and the combination by two lasers, showed melting covering some dentinal tubules The thermographic study found the temperature increase was not more than 6 deg C. This study showed the safety parameters applications of Er:YAG laser in association with Nd:YAG laser in root canal treatment, in order to not cause thermal damages to the periodontal tissues. (author)

  19. Photocatalytic degradation and mineralization of microcystin-LR under UV-A, solar and visible light using nanostructured nitrogen doped TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Triantis, T.M.; Fotiou, T. [Laboratory of Catalytic - Photocatalytic Processes (Solar Energy - Environment), Institute of Physical Chemistry, National Center for Scientific Research ' Demokritos' , Neapoleos 25, 15310 Agia Paraskevi, Attiki (Greece); Kaloudis, T. [Organic Micropollutants Laboratory, Athens Water Supply and Sewerage Company (EYDAP SA), WTP Aharnon, Menidi (Greece); Kontos, A.G.; Falaras, P. [Laboratory of Photo-redox Conversion and Storage of Solar Energy, Institute of Physical Chemistry, National Center for Scientific Research ' Demokritos' , Neapoleos 25, 15310 Agia Paraskevi, Attiki (Greece); Dionysiou, D.D.; Pelaez, M. [Environmental Engineering and Science Program, School of Energy, Environmental, Biological and Medical Engineering, University of Cincinnati, OH 45221-0012 (United States); Hiskia, A., E-mail: hiskia@chem.demokritos.gr [Laboratory of Catalytic - Photocatalytic Processes (Solar Energy - Environment), Institute of Physical Chemistry, National Center for Scientific Research ' Demokritos' , Neapoleos 25, 15310 Agia Paraskevi, Attiki (Greece)

    2012-04-15

    Highlights: Black-Right-Pointing-Pointer N-TiO{sub 2} exhibited effective degradation of MC-LR under UV-A, solar and visible light. Black-Right-Pointing-Pointer Complete photocatalytic mineralization of MC-LR was achieved under UV-A and solar light. Black-Right-Pointing-Pointer The organic nitrogen is mainly released as ammonium and nitrate ions. - Abstract: In an attempt to face serious environmental hazards, the degradation of microcystin-LR (MC-LR), one of the most common and more toxic water soluble cyanotoxin compounds released by cyanobacteria blooms, was investigated using nitrogen doped TiO{sub 2} (N-TiO{sub 2}) photocatalyst, under UV-A, solar and visible light. Commercial Degussa P25 TiO{sub 2}, Kronos and reference TiO{sub 2} nanopowders were used for comparison. It was found that under UV-A irradiation, all photocatalysts were effective in toxin elimination. The higher MC-LR degradation (99%) was observed with Degussa P25 TiO{sub 2} followed by N-TiO{sub 2} with 96% toxin destruction after 20 min of illumination. Under solar light illumination, N-TiO{sub 2} nanocatalyst exhibits similar photocatalytic activity with that of commercially available materials such as Degussa P25 and Kronos TiO{sub 2} for the destruction of MC-LR. Upon irradiation with visible light Degussa P25 practically did not show any response, while the N-TiO{sub 2} displayed remarkable photocatalytic efficiency. In addition, it has been shown that photodegradation products did not present any significant protein phosphatase inhibition activity, proving that toxicity is proportional only to the remaining MC-LR in solution. Finally, total organic carbon (TOC) and inorganic ions (NO{sub 2}{sup -}, NO{sub 3}{sup -} and NH{sub 4}{sup +}) determinations confirmed that complete photocatalytic mineralization of MC-LR was achieved under both UV-A and solar light.

  20. UV Irradiance Enhancements by Scattering of Solar Radiation from Clouds

    Directory of Open Access Journals (Sweden)

    Uwe Feister

    2015-08-01

    Full Text Available Scattering of solar radiation by clouds can reduce or enhance solar global irradiance compared to cloudless-sky irradiance at the Earth’s surface. Cloud effects to global irradiance can be described by Cloud Modification Factors (CMF. Depending on strength and duration, irradiance enhancements affect the energy balance of the surface and gain of solar power for electric energy generation. In the ultraviolet region, they increase the risk for damage to living organisms. Wavelength-dependent CMFs have been shown to reach 1.5 even in the UV-B region at low altitudes. Ground-based solar radiation measurements in the high Andes region at altitudes up to 5917 m a.s.l showed cloud-induced irradiance enhancements. While UV-A enhancements were explained by cloud scattering, both radiation scattering from clouds and Negative Ozone Anomalies (NOA have been discussed to have caused short-time enhancement of UV-B irradiance. Based on scenarios using published CMF and additional spectroradiometric measurements at a low-altitude site, the contribution of cloud scattering to the UV-B irradiance enhancement in the Andes region has been estimated. The range of UV index estimates converted from measured UV-B and UV-A irradiance and modeled cloudless-sky ratios UV-B/erythemal UV is compatible with an earlier estimate of an extreme UV index value of 43 derived for the high Andes.

  1. Morphology, anatomy and histology of Doto uva Marcus, 1955 (Opisthobranchia: Nudibranchia) from the Chilean coast

    NARCIS (Netherlands)

    Fischer, M.A.; Velde, van der G.; Roubos, E.W.

    2006-01-01

    Doto uva Marcus, 1955 is a nudibranch species recorded from the Brazilian and Chilean coast. In spite of its wide distribution, D. uva has been described only superficially, mainly as to the pattern of its coloration, external morphology, radular teeth and reproductive system. Here we substantially

  2. UV-A radiation effects on higher plants: Exploring the known unknown.

    Science.gov (United States)

    Verdaguer, Dolors; Jansen, Marcel A K; Llorens, Laura; Morales, Luis O; Neugart, Susanne

    2017-02-01

    Ultraviolet-A radiation (UV-A: 315-400nm) is a component of solar radiation that exerts a wide range of physiological responses in plants. Currently, field attenuation experiments are the most reliable source of information on the effects of UV-A. Common plant responses to UV-A include both inhibitory and stimulatory effects on biomass accumulation and morphology. UV-A effects on biomass accumulation can differ from those on root: shoot ratio, and distinct responses are described for different leaf tissues. Inhibitory and enhancing effects of UV-A on photosynthesis are also analysed, as well as activation of photoprotective responses, including UV-absorbing pigments. UV-A-induced leaf flavonoids are highly compound-specific and species-dependent. Many of the effects on growth and development exerted by UV-A are distinct to those triggered by UV-B and vary considerably in terms of the direction the response takes. Such differences may reflect diverse UV-perception mechanisms with multiple photoreceptors operating in the UV-A range and/or variations in the experimental approaches used. This review highlights a role that various photoreceptors (UVR8, phototropins, phytochromes and cryptochromes) may play in plant responses to UV-A when dose, wavelength and other conditions are taken into account. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Photocatalytic Oxidation of Triiodide in UVA-Exposed Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Matthew Carnie

    2012-01-01

    Full Text Available UVA irradiation of glass mounted dye-sensitized solar cells without UV filtration causes failure within 400 hours of light exposure. The failure mode is shown to relate to consumption of I3−, which is directly related to TiO2 photo-catalysis. The onset of failure is easily determined from electrochemical impedance data where the recombination resistance of the TiO2/electrolyte back reaction drops markedly prior to the onset of degradation. At the point of complete cell failure this impedance value then dramatically increases as there is no longer an interfacial reaction possible between the TiO2 and the I3− depleted electrolyte. Device failure is most rapid for cells under electrical load indicating that the degradation of the electrolyte is related to photogenerated hole production by excitation of the TiO2. Once depleted by UV exposure, the I3− can be regenerated by simple application of a reverse bias which can restore severely UV degraded devices to near original working conditions.

  4. Effect of irradiance, sucrose, and CO2 concentration on the growth of potato (Solanum tuberosum L.) in vitro

    Science.gov (United States)

    Yorio, Neil C.; Wheeler, Raymond M.; Weigel, Russell C.

    1995-01-01

    Growth measurements were taken of potato plantlets (Solanum tuberosum L.) cvs. Norland (NL), Denali (DN), and Kennebec (KN), grown in vitro. Studies were conducted in a growth chamber, with nodal explants grown for 21 days on Murashige and Skoog salts with either 0, 1, 2, or 3% sucrose and capped with loose-fitted Magenta 2-way caps that allowed approximately 2.25 air exchanges/hour. Plantlets were exposed to either 100 or 300 micro mol/sq m/s photosynthetic photon flux (PPF), and the growth chamber was maintained at either 400 or 4000 micro mol/mol CO2. Regardless of PPF, all cvs. that were grown at 4000 micro mol/mol CO2 showed significant increases in total plantlet dry weight (TDW) and shoot length (SL) when sucrose was omitted from the media, indicating an autotrophic response. At 400 micro mol/mol CO2, all cvs. showed an increase in TDW and SL with increasing sucrose under both PPF levels. Within any sucrose treatment, the highest TDW for all cvs. resulted from 300 micro mol/sq m/s PPF and 4000 micro mol/mol CO2 At 4000 micro mol/mol CO2, TDW showed no further increase with sucrose levels above 1% for cvs. NL and DN at both PPF levels, suggesting that sucrose levels greater than 1% may hinder growth when CO2 enrichment is used.

  5. Solar disinfection of drinking water (SODIS): an investigation of the effect of UV-A dose on inactivation efficiency.

    Science.gov (United States)

    Ubomba-Jaswa, Eunice; Navntoft, Christian; Polo-López, M Inmaculada; Fernandez-Ibáñez, Pilar; McGuigan, Kevin G

    2009-05-01

    The effect of solar UV-A irradiance and solar UV-A dose on the inactivation of Escherichia coli K-12 using solar disinfection (SODIS) was studied. E. coli K-12 was seeded in natural well-water contained in borosilicate glass tubes and exposed to sunlight at different irradiances and doses of solar UV radiation. In addition, E. coli K-12 was also inoculated into poly(ethylene) terephthalate (PET) bottles and in a continuous flow system (10 L min(-1)) to determine the effect of an interrupted and uninterrupted solar dose on inactivation. Results showed that inactivation from approximately 10(6) CFU mL(-1) to below the detection level (4 CFU/mL) for E. coli K-12, is a function of the total uninterrupted dose delivered to the bacteria and that the minimum dose should be >108 kJ m(-2) for the conditions described (spectral range of 0.295-0.385 microm). For complete inactivation to below the limit of detection, this dose needs to be received regardless of the incident solar UV intensity and needs to be delivered in a continuous and uninterrupted manner. This is illustrated by a continuous flow system in which bacteria were not fully inactivated (residual viable concentration approximately 10(2) CFU/mL) even after 5 h of exposure to strong sunlight and a cumulative dose of >108 kJ m(-2). This has serious implications for attempts to scale-up solar disinfection through the use of re-circulatory continuous flow reactors.

  6. Solar or UVA-Visible Photocatalytic Ozonation of Water Contaminants.

    Science.gov (United States)

    Beltrán, Fernando J; Rey, Ana

    2017-07-14

    An incipient advanced oxidation process, solar photocatalytic ozonation (SPO), is reviewed in this paper with the aim of clarifying the importance of this process as a more sustainable water technology to remove priority or emerging contaminants from water. The synergism between ozonation and photocatalytic oxidation is well known to increase the oxidation rate of water contaminants, but this has mainly been studied in photocatalytic ozonation systems with lamps of different radiation wavelength, especially of ultraviolet nature (UVC, UVB, UVA). Nowadays, process sustainability is critical in environmental technologies including water treatment and reuse; the application of SPO systems falls into this category, and contributes to saving energy and water. In this review, we summarized works published on photocatalytic ozonation where the radiation source is the Sun or simulated solar light, specifically, lamps emitting radiation to cover the UVA and visible light spectra. The main aspects of the review include photoreactors used and radiation sources applied, synthesis and characterization of catalysts applied, influence of main process variables (ozone, catalyst, and pollutant concentrations, light intensity), type of water, biodegradability and ecotoxicity, mechanism and kinetics, and finally catalyst activity and stability.

  7. SnO{sub 2} foam grain-shaped nanoparticles: Synthesis, characterization and UVA light induced photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Abdelkader, Elaziouti, E-mail: elaziouti_a@yahoo.com [Laboratory of Electronic Microscope and Materials Science, University of Science and Technology of Oran (USTO M. B), BP 1505 El M' naouar, 31000 Oran (Algeria); Nadjia, Laouedj, E-mail: nlaouedj@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, University of Science and Technology of Oran (USTO M. B), BP 1505 El M' naouar, 31000 Oran (Algeria); Naceur, Benhadria, E-mail: nacer1974@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, University of Science and Technology of Oran (USTO M. B), BP 1505 El M' naouar, 31000 Oran (Algeria); Noureddine, Bettahar, E-mail: nbettahar2001@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, University of Science and Technology of Oran (USTO M. B), BP 1505 El M' naouar, 31000 Oran (Algeria)

    2016-09-15

    Cassiterite (tin oxide; SnO{sub 2}) nanoparticles (NPs), has been successfully synthesized via a sol-gel method. The obtained compounds are subsequently calcined at 80, 450 and 650 °C for 4 h and are assigned as SnO{sub 2}-80, SnO{sub 2}-450 NPs and SnO{sub 2}-650 NPs, respectively. All prepared samples were characterized using thermogravimetric analysis coupled with mass spectroscopy (TG-SM), X-ray diffraction (XRD), scanning electron microscope (SEM) and UV–vis diffuse reflectance spectroscopy (UV–vis DRS). The XRD results confirmed the aggregated cassiterite SnO{sub 2} nanoparticles (NPs) with a size ranging from 13 to 23 nm. The absorption edge of the SnO{sub 2} NPs samples calcined at higher temperatures showed 25 nm (SnO{sub 2}-450 NPs) and 10 nm (SnO{sub 2}-650 NPs) red shifted compared with that of commercial SnO{sub 2}-com NPs sample. The photodegradation efficiency of SnO{sub 2} NPs was investigated using Congo red (CR) dye, as model organic pollutant. The effect of environmental factors (e.g., reaction time and calcination temperature) on the photocatalysis process of CR on SnO{sub 2} NPs was investigated in photocatalysis process under UVA light irradiation. We found that the SnO{sub 2}-650 NPs with 23 nm particle size and about 3.49 eV band gap was higher than that of the SnO{sub 2}-450 as well as the commercial SnO{sub 2}-com NPs. Pseudo-first-order kinetic model gave the best fit, with highest correlation coefficients (R{sup 2} ≥ 0.95). On the basis of the energy band diagram positions, the enhanced photodegradation efficiency SnO{sub 2} NPs catalyst could be proceeded via direct reactions with (O{sub 2}·{sup -} and ·OH), as active oxidative species involved in the photocatalysis process of CR dye under UVA-light irradiation. - Highlights: • SnO{sub 2} NPs photocatalysts were synthesized using a facile sol–gel route. • As-prepared SnO{sub 2} NPs were characterized by XRD, SEM and UV–vis-DRS techniques. • Noticeably UVA

  8. Irradiation of root cervical dentin by using the Nd:YAG laser in vitro study and scanning electron microscopy; Irradiacao de dentina cervical radicular com laser de Nd:YAG - estudo in vitro e microscopia eletronica de varredura

    Energy Technology Data Exchange (ETDEWEB)

    Britto, Cynthia Tannure Coelho

    2003-07-01

    The dentin hypersensitivity occurs as a result of the dentine exposition to the oral environment, due to loss or removal of enamel or cementum, or both. The hypersensitivity can persist, unless the sealing of the dentin tubules be carried out. Several treatments have been considered, but with less satisfactory and only temporary results. Among these treatments we can cite methods that promote the mechanical occlusion by deposition of substances inside of tubules, by topic application. Nowadays, among the treatments studied, there is the use of lasers, which leads to better clinical efficiency by promoting fusion and re-solidification of the dentin surface, obliterating total or partially the dentin tubules. This in-vitro study was carried out in order to evaluate the efficiency of the Nd:YAG laser in promoting the fusion and re-solidification of the dentin surface, and to evaluate parameters of irradiation typically used, comparing results using photoinitiator with those without it. By observation of the dentin surface, using Scanning Electron Microscopy, it was found extensive areas of fusion and re-solidification, in those groups with photoinitiator, being this technique an efficient resource in the treatment of the dentin hypersensitivity. (author)

  9. Estudo cinético da secagem da uva Isabel para produção de uva passa

    Directory of Open Access Journals (Sweden)

    Antônio Vitor Machado

    2015-03-01

    Full Text Available A fruticultura é um dos segmentos mais importantes na agricultura nacional, porém um grande problema enfrentado pelos fruticultores é a conservação dos frutos maduros. A falta de tecnologias adequadas para o melhor aproveitamento dos frutos tem resultado em um alto índice de desperdício, cerca de toneladas ano. A uva Isabel, é uma das principais variedades Vitis labrusca, que apresenta sabor característico e pigmentação bastante acentuada, destacando-se como uva de mesa comum, apresentando-se como uma variedade de grande aceitação pelo consumidor e pela indústria de alimentos. A desidratação de frutas vem sendo objeto de muitas pesquisas com o propósito de se obter técnicas que proporcionem, além de baixo custo de produção, a manutenção da qualidade dos produtos desidratados e a redução das perdas pós-colheita. Neste sentido o presente trabalho objetivou estudar a secagem da uva Isabel para obtenção de uva passa desidratada, visando obter informações sobre a qualidade do fruto in-natura e após processamento, realizando-se para isto à caracterização físico-química do fruto in-natura e desidratado. Foram realizadas análises de pH, sólidos solúveis, acidez total titulável,  umidade, atividade de água e do teor de antocianinas nos Laboratórios de Tecnologia da UFERSA e UFCG. De acordo com os resultados obtidos, os frutos desidratados apresentaram um incremento nos teores de sólidos solúveis (de 11,17 para 45° brix, da acidez titulável (de 0,73 para 1,34% e do teor de antocianina, que foi elevado de 117,83 mg/100g para 380,52 mg/100g de fruto desidratado, e redução quanto aos valores de umidade (de 85,65 para 21,75% e atividade de água (de 0,90 para 0,66, estes valores de nutrientes apresentaram-se próximos aos relatados na literatura demonstrando que a secagem solar é uma excelente alternativa para a conservação da uva Isabel, contribuindo assim para redução das perdas pós-colheita e com a

  10. UV Irradiation and Humic Acid Mediate Aggregation of Aqueous Fullerene (nC60) Nanoparticles

    Science.gov (United States)

    The transport and fate of engineered nanomaterials is affected by multiple environmental factors, including sunlight and natural organic matter. In this study, the initial aggregation kinetics of aqueous fullerene (nC60) nanoparticles before and after UVA irradiation was investig...

  11. Surface morphology of sound deciduous tooth enamel after application of a photo-absorbing cream and infrared low-level laser irradiation: an in vitro scanning electron microscopy study.

    Science.gov (United States)

    De Sant'Anna, Giselle Rodrigues; Paleari, Giovanna Souza Leão; Duarte, Danilo Antônio; Brugnera, Aldo; Soares, Cristina Pacheco

    2007-12-01

    The purpose of this descriptive scanning electron microscopic study was to characterize surface alterations in deciduous tooth enamel after in vitro infrared diode laser irradiation, using a photo-absorbing agent alone and also combined with fluoride, before and after laser irradiation. Previous investigations have demonstrated increased enamel caries resistance after laser irradiation. Seven extracted or exfoliated primary molar teeth underwent soft tissue débridement and fluoride-free prophylaxis. Buccal surfaces were determined to be caries free by macroscopic examination. Sample groups were divided into: (1) control (no treatment); (2) infrared diode laser irradiation (lambda = 810 nm, 68 nm, 60 mW/mm(2), 30 W) using the photo-absorbing agent alone (IRDL + PA; 500 J/cm(2)); and (3) infrared diode laser irradiation using a photo-absorbing agent combined with 2% fluoride (IRDL + PFA; 500 J/cm(2)). Buccal surfaces were evaluated following standard scanning electron microscopy preparation techniques. Control samples of enamel surfaces were relatively smooth but presented occasional enamel prism ends. There were no areas with cavitations or surface defects. After the IRDL + PA treatment, irradiated surfaces became rough and mildly to moderately irregular with scarce enamel cavitations and without exposure of enamel prism ends. The surfaces had adherent granules and only occasional fine cracks and porosities in surface coatings were noted. After the IRDL + PFA treatment, there was a homogenous confluent surface that masked typical enamel surface markings. The surfaces had well-defined globules resulting from the IRDL + PFA treatment, that were not seen after IRDL + PA treatment. Treatment of deciduous tooth enamel with infrared diode laser irradiation using a photo-absorbing agent and a photo-absorbing agent combined with 2% fluoride created surface coatings that may act as reservoirs for mineral phases during cariogenic activity on enamel, and also provide a

  12. The Effect of Riboflavin/UVA Collagen Cross-linking Therapy on the Structure and Hydrodynamic Behaviour of the Ungulate and Rabbit Corneal Stroma

    Science.gov (United States)

    Hayes, Sally; Kamma-Lorger, Christina S.; Boote, Craig; Young, Robert D.; Quantock, Andrew J.; Rost, Anika; Khatib, Yasmeen; Harris, Jonathan; Yagi, Naoto; Terrill, Nicholas; Meek, Keith M.

    2013-01-01

    Purpose To examine the effect of riboflavin/UVA corneal crosslinking on stromal ultrastructure and hydrodynamic behaviour. Methods One hundred and seventeen enucleated ungulate eyes (112 pig and 5 sheep) and 3 pairs of rabbit eyes, with corneal epithelium removed, were divided into four treatment groups: Group 1 (28 pig, 2 sheep and 3 rabbits) were untreated; Group 2 (24 pig) were exposed to UVA light (3.04 mW/cm2) for 30 minutes and Group 3 (29 pig) and Group 4 (31 pig, 3 sheep and 3 rabbits) had riboflavin eye drops applied to the corneal surface every 5 minutes for 35 minutes. Five minutes after the initial riboflavin instillation, the corneas in Group 4 experienced a 30 minute exposure to UVA light (3.04 mW/cm2). X-ray scattering was used to obtain measurements of collagen interfibrillar spacing, spatial order, fibril diameter, D-periodicity and intermolecular spacing throughout the whole tissue thickness and as a function of tissue depth in the treated and untreated corneas. The effect of each treatment on the hydrodynamic behaviour of the cornea (its ability to swell in saline solution) and its resistance to enzymatic digestion were assessed using in vitro laboratory techniques. Results Corneal thickness decreased significantly following riboflavin application (pcollagen parameters were unaltered by cross-linking, even within the most anterior 300 microns of the cornea. The cross-linking treatment had no effect on the hydrodynamic behaviour of the cornea but did cause a significant increase in its resistance to enzymatic digestion. Conclusions It seems likely that cross-links formed during riboflavin/UVA therapy occur predominantly at the collagen fibril surface and in the protein network surrounding the collagen. PMID:23349690

  13. [The intervention of nicotinamide on skin melanocyte's cell proliferation after UVA (365 nm) exposed.].

    Science.gov (United States)

    Patam, Muhammad; Jin, Xi-peng; Pan, Jian-ying; Shen, Guang-zu; Jin, Tai-Yi

    2005-02-01

    To investigate the interference effect of nicotinamide on UVA-induced cell proliferation in human skin melanocyte. To apply the optimum UVA dose expected to cause cell proliferation: 0.2 cm2, nicotinamide was added after the 0.2 cm2 UVA exposure immediately or 48 h later, then the rate of cell proliferation, calcium concentration and the activities of Na+-K+, Ca2+-ATP enzymes of melanocytes were measured respectively. After treatment with 1.000 mg/ml nicotinamide following UVA exposure, the rate of cell proliferation was decreased significantly 24 hours later. Treatment with 0.125 mg/ml nicotinamide 48 hours after UVA exposure also significantly inhibited the cell proliferation; 1.25 mg/ml nicotinamide increased calcium concentration in cells; 0.250 mg/ml nicotinamide increased the activities of Na+-K+, Ca2+-ATP enzymes in melanocytes (P Nicotinamide has more obvious effect on inhibiting melanocyte's proliferation if added immediately following UVA exposure. Our discovery indicated that nicotinamide may affect the melanocyte through modulating the calcium concentration. It is possible to consider nicotinamide as an efficient and safe sun screen to provide a certain level of protection for UVA exposed skin.

  14. Autophagic-lysosomal dysregulation downstream of cathepsin B inactivation in human skin fibroblasts exposed to UVA.

    Science.gov (United States)

    Lamore, Sarah D; Wondrak, Georg T

    2012-01-01

    Recently, using 2D-DIGE proteomics we have identified cathepsin B as a novel target of UVA in human Hs27 skin fibroblasts. In response to chronic exposure to noncytotoxic doses of UVA (9.9 J cm(-2), twice a week, 3 weeks), photooxidative impairment of cathepsin B enzymatic activity occurred with accumulation of autofluorescent aggregates colocalizing with lysosomes, an effect mimicked by pharmacological antagonism of cathepsin B using the selective inhibitor CA074Me. Here, we have further explored the mechanistic involvement of cathepsin B inactivation in UVA-induced autophagic-lysosomal alterations using autophagy-directed PCR expression array analysis as a discovery tool. Consistent with lysosomal expansion, UVA upregulated cellular protein levels of the lysosomal marker glycoprotein Lamp-1, and increased levels of the lipidated autophagosomal membrane constituent LC3-II were detected. UVA did not alter expression of beclin 1 (BECN1), an essential factor for initiation of autophagy, but upregulation of p62 (sequestosome 1, SQSTM1), a selective autophagy substrate, and α-synuclein (SNCA), an autophagic protein substrate and aggresome component, was observed at the mRNA and protein level. Moreover, UVA downregulated transglutaminase-2 (TGM2), an essential enzyme involved in autophagolysosome maturation. Strikingly, UVA effects on Lamp-1, LC3-II, beclin 1, p62, α-synuclein, and transglutaminase-2 were mimicked by CA074Me treatment. Taken together, our data suggest that UVA-induced autophagic-lysosomal alterations occur as a consequence of impaired autophagic flux downstream of cathepsin B inactivation, a novel molecular mechanism potentially involved in UVA-induced skin photodamage. This journal is © The Royal Society of Chemistry and Owner Societies 2012

  15. Effect of UVA/Riboflavin Collagen Crosslinking on Biomechanics of Artificially Swollen Corneas.

    Science.gov (United States)

    Hatami-Marbini, Hamed; Jayaram, Sandeep M

    2018-02-01

    The purpose of this study was to characterize the relation between corneal hydration and stiffening effects of the UVA/riboflavin collagen crosslinking treatment and to investigate how artificially swelling the cornea prior to this treatment procedure affects tensile property improvement. Porcine corneas were collagen crosslinked in vitro at different hydration levels using a number of hypoosmolar and isoosmolar riboflavin solutions. Thickness of the specimens prior to crosslinking was taken as a proxy for their hydration and was used to divide them into different thickness groups. A Dynamic Mechanical Analysis (DMA) machine was used to perform mechanical tensile tests. The hydration of specimens during the mechanical tests was kept similar to the hydration at which they were crosslinked. The recorded force was used to calculate the maximum tensile stress and tangent modulus as a function of thickness (hydration) prior to collagen crosslinking treatment. Collagen crosslinking with either a hypoosmolar or isoosmolar solution significantly increased corneal tensile modulus (P crosslinking showed significantly softer tensile properties compared with those that were crosslinked at lower hydration (P degree of tensile property improvement was hydration dependent, the stiffness of samples crosslinked at higher hydration was not significantly different than the stiffness of those crosslinked at lower hydration when the hydration was kept similar in the mechanical experiments. Swelling porcine corneas to the different extents prior to collagen crosslinking treatment does not significantly change the amount of biomechanical improvement if tensile properties are measured at similar hydration.

  16. Antimicrobial susceptibility of photodynamic therapy (UVA/riboflavin against Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Renata Tiemi Kashiwabuchi

    2012-12-01

    Full Text Available PURPOSE: To assess S. aureus in vitro viability after the exposure to ultraviolet light A (UVA and riboflavin (B2. METHODS: Samples of S. aureus in 96 well plates (in triplicate were exposed to riboflavin (B2 and ultraviolet light A (365 nm wavelength at a power density of 3 mW/cm², 8 mm spot diameter, for 30 minutes. Control groups were prepared as well in triplicate: blank control, ultraviolet light A only, riboflavin only and dead bacteria Control. The bacterial viability was measured using fluorescent microscopy. In order to investigate the occurrence of "viable but non-culturable" microorganisms after treatment, the cell viability was also investigated by plate culture procedure onto a broth medium. Statistical analysis was performed using the triplicate values from each experimental condition. RESULTS: No difference was observed among the treatment group and the control samples (p=1. CONCLUSION: The combination of riboflavin 0.1% and ultraviolet light A at 365 nm did not exhibit antimicrobial activity against oxacillin susceptible S. aureus.

  17. Reguladores vegetais influenciando numero e tamanho de celulas das bagas da uva 'Niagara Rosada'

    National Research Council Canada - National Science Library

    Vieira, Cassia Regina Yuriko Ide; Pires, Erasmo Jose Paioli; Terra, Maurilo Monteiro; Tecchio, Marco Antonio; Vieira, Maria Do Carmo

    2008-01-01

    O objetivo do trabalho foi avaliar o efeito do acido giberelico, thidiazuron e quinmerac na anatomia das bagas de uvas cultivar 'Niagara Rosada', provenientes de vinhedo localizado em Dourados - MS...

  18. Coilin is rapidly recruited to UVA-induced DNA lesions and γ-radiation affects localized movement of Cajal bodies.

    Science.gov (United States)

    Bártová, Eva; Foltánková, Veronika; Legartová, Soňa; Sehnalová, Petra; Sorokin, Dmitry V; Suchánková, Jana; Kozubek, Stanislav

    2014-01-01

    Cajal bodies are important nuclear structures containing proteins that preferentially regulate RNA-related metabolism. We investigated the cell-type specific nuclear distribution of Cajal bodies and the level of coilin, a protein of Cajal bodies, in non-irradiated and irradiated human tumor cell lines and embryonic stem (ES) cells. Cajal bodies were localized in different nuclear compartments, including DAPI-poor regions, in the proximity of chromocenters, and adjacent to nucleoli. The number of Cajal bodies per nucleus was cell cycle-dependent, with higher numbers occurring during G2 phase. Human ES cells contained a high coilin level in the nucleoplasm, but coilin-positive Cajal bodies were also identified in nuclei of mouse and human ES cells. Coilin, but not SMN, recognized UVA-induced DNA lesions, which was cell cycle-independent. Treatment with γ-radiation reduced the localized movement of Cajal bodies in many cell types and GFP-coilin fluorescence recovery after photobleaching was very fast in nucleoplasm in comparison with GFP-coilin recovery in DNA lesions. By contrast, nucleolus-localized coilin displayed very slow fluorescence recovery after photobleaching, which indicates very slow rates of protein diffusion, especially in nucleoli of mouse ES cells.

  19. Autophagic-lysosomal dysregulation downstream of cathepsin B inactivation in human skin fibroblasts exposed to UVA

    OpenAIRE

    Lamore, Sarah D.; Wondrak, Georg T.

    2011-01-01

    Recently, using 2D-DIGE proteomics we have identified cathepsin B as a novel target of UVA in human Hs27 skin fibroblasts. In response to chronic exposure to noncytotoxic doses of UVA (9.9 J/cm2, twice a week, 3 weeks), photooxidative impairment of cathepsin B enzymatic activity occurred with accumulation of autofluorescent aggregates colocalizing with lysosomes, an effect mimicked by pharmacological antagonism of cathepsin B using the selective inhibitor CA074Me. Here, we have further explor...

  20. Cellular Studies with UVA Radiation: A Role for Iron (invited paper)

    Energy Technology Data Exchange (ETDEWEB)

    Tyrrell, R.M.; Pourzand, C.A.; Brown, J.; Hejmadi, V.; Kvam, V.; Ryter, S.; Watkin, R.D

    2000-07-01

    The UVA (320-380 nm) component of sunlight or sunbeds acts as an oxidising carcinogen and has been clearly implicated in skin cancer. Since UVA radiation interacts with cells by generating active oxygen species, the damaging effects of this radiation will be exacerbated by the presence of catalytically reactive iron in cells. It has now been shown by two independent techniques (dequenching of metal-quenched calcein fluorescence in cells and changes in the binding activity of the iron responsive protein IRPI) that UVA radiation causes an immediate release of 'free' iron in human skin fibroblasts via the proteolysis of ferritin (Ft). Within minutes of exposure to a range of doses of UVA at natural exposure levels, the binding activity of IRP-1, as well as Ft levels, decrease in a dose-dependent manner. It is proposed that the oxidative damage to lysosomes that leads to Ft degradation and the consequent release of potentially harmful 'free' iron to the cytosol might be a major factor in UVA-induced damage to the skin. UVA radiation also breaks down heme-containing proteins in the microsomal membrane to release free heme as an additional photosensitising component. This will provide another source of enhanced free iron in skin cells since constitutive heme oxygenase 2 (in keratinocytes) and UVA-inducible heme oxygenase-1 (in fibroblasts) are likely to break down any free heme to biliverdin and release iron and carbon monoxide in the process. It is postulated that, in skin fibroblasts, this free heme release and the enhanced free iron pools will lead to an adaptive response involving heme oxygenase (with a maximum about 10 h) and ferritin (in 24-48 h) that will scavenge the heme and iron released by subsequent oxidising (UVA) treatments. (author)

  1. Sunlight-induced immunosuppression in humans is initially because of UVB, then UVA, followed by interactive effects.

    Science.gov (United States)

    Poon, Terence S C; Barnetson, Ross St C; Halliday, Gary M

    2005-10-01

    Solar-simulated ultraviolet radiation (ssUV) suppresses immunity in humans. The ultraviolet B (UVB) waveband is recognized as immunosuppressive; however the relative significance of UVA to ssUV immunosuppression is unknown. We created dose and time-response curves for UVB-, UVA-, and ssUV-induced suppression of memory immunity to nickel in humans. UVB caused immunosuppression within 24 h. UVA immunosuppression required 48 h and was normalized by 72 h. UVB alone accounts for ssUV immunosuppression at 24 h, but both UVB and UVA contributed at 48 h. By 72 h neither waveband accounted for ssUV immunosuppression. An interaction between these wavebands was therefore the major contributor. To confirm this dose-response curves were used to determine immune protection factors (IPF) for sunscreens with nickel challenge 72 h following ssUV. A sunscreen with good UVA protection had an IPF twice that of a poor UVA protector, despite providing similar protection from sunburn. Thus UVA was a major contributor to ssUV-induced immunosuppression at 72 h but only with the cooperation of UVB. Hence, UVB initiates immunosuppressive signals within 24 h, followed by UVA at 48 h, then an interaction between UVB and UVA. By 72 h following ssUV exposure, neither UVB nor UVA, but an interaction between them is the major cause of sunlight-induced immunosuppression.

  2. Comparative evaluation of microhardness and morphology of permanent tooth enamel surface after laser irradiation and fluoride treatment - An in vitro study.

    Science.gov (United States)

    Kumar, Puneet; Goswami, Mridula; Dhillon, Jatinder Kaur; Rehman, Ferah; Thakkar, Deepti; Bharti, Kusum

    2016-10-01

    Background and aims: The aim of the study was to evaluate and compare the surface microhardness and surface morphology of permanent tooth enamel after Er,Cr:YSGG laser irradiation and Fluoride application. Materials and methods: One hundred and twenty premolars extracted for orthodontic purpose were used in the study and randomly divided into 6 groups. Group A was not subjected to any treatment. Group B was subjected to Er,Cr:YSGG laser irradiation. Group C was subjected to Er,Cr:YSGG laser irradiation followed by application of 2% NaF gel for 4 minutes. Group D was subjected to laser irradiation and 1.23% APF gel for 4 minutes. Group E was subjected to 2% NaF gel pretreatment technique followed by laser irradiation. Group F was subjected to 1.23% APF gel pretreatment technique followed by laser irradiation. All the test groups were subjected to microhardness testing and scanning electron microscope evaluation at 500 X and 1500 X. Results: All the treated groups showed an increase in microhardness value in comparison to the control group. The highest increase in microhardness was seen in Group F. Increase in microhardness values of Group B and Group D was not statistically significant as compared to Group A. Scanning Electron Micrographs showed few craters and fine porosities for Group A. These craters and porosities increased in size and often showed glass like appearance after laser irradiation. Conclusions: It can be suggested by means of present study that Er,Cr:YSGG laser irradiation alone or in combination with fluoride gel is an effective tool to provide resistance against the caries. Significantly higher resistance (p< 0.05) was seen when APF gel was used prior to Er,Cr:YSGG laser irradiation and this combination can act as an efficient tool for prevention against dental caries.

  3. In vitro investigation of head and neck cancer stem cell proportions and their changes following X-ray irradiation as a function of HPV status.

    Science.gov (United States)

    Reid, Paul; Wilson, Puthenparampil; Li, Yanrui; Marcu, Loredana G; Staudacher, Alexander H; Brown, Michael P; Bezak, Eva

    2017-01-01

    Some head and neck squamous cell carcinomas (HNSCC) have a distinct aetiology, which depends on the presence of oncogenic human papilloma virus (HPV). Also, HNSCC contains cancer stem cells (CSCs) that have greater radioresistance and capacity to change replication dynamics in response to irradiation compared to non-clonogenic cells. Since there is limited data on CSCs in HNSCC as a function of HPV status, better understanding of their radiobiology may enable improved treatment outcome. Baseline and post-irradiation changes in CSC proportions were investigated by flow cytometry in a HPV-negative (UM-SCC-1) and a HPV-positive (UM-SCC-47) HNSCC cell line, using fluorescent staining with CD44/ALDH markers. CSC proportions in both irradiated and unirradiated cultures were compared for the two cell lines at various times post-irradiation. To assess repopulation of CSCs, untreated cultures were depleted of CD44+/ALDH+ cells and re-cultured for 3 weeks before flow cytometry analysis. CSC proportions in untreated cell lines were 0.57% (UM-SCC-1) and 2.87% (UM-SCC-47). Untreated cell lines depleted of CD44+/ALDH+ repopulated this phenotype to a mean of 0.15% (UM-SCC-1) and 6.76% (UM-SCC-47). All UM-SCC-47 generations showed elevated CSC proportions after irradiation, with the most significant increase at 2 days post-irradiation. The highest elevation in UM-SCC-1 CSCs was observed at 1 day post-irradiation in the 2nd generation and at 3 days after irradiation in the 3rd generation. When measured after 10 days, only the 3rd generation of UM-SCC-1 showed elevated CSCs. CSC proportions in both cell lines were elevated after exposure and varied with time post irradiation. UM-SCC-47 displayed significant plasticity in repopulating the CSC phenotype in depleted cultures, which was not seen in UM-SCC-1.

  4. Ultraviolet A irradiation increases the permeation of fullerenes into human and porcine skin from C₆₀-poly(vinylpyrrolidone) aggregate dispersions.

    Science.gov (United States)

    Souto, Gabriele Dadalt; Pohlmann, Adriana Raffin; Guterres, Sílvia Stanisçuaski

    2015-01-01

    The purpose of this study was to characterise C₆₀-poly(vinylpyrrolidone) (PVP) dispersions, to analyse the cutaneous absorption of fullerenes as well as to evaluate whether UVA radiation (UVA-R) could modify its permeation profile. Dispersions were characterised according to their pH, particle size, zeta potential, and morphology. Skin absorption studies were performed using porcine or human skin under UVA or sham irradiation. The C₆₀ aggregate size was 129 ± 54 nm (as determined by nanoparticle tracking analysis) and the zeta potential was -4.93 ± 1.72 mV. The C₆₀ aggregates presented an irregular shape (as measured by transmission electron microscopy) and permeated through human and porcine skin. C₆₀-PVP aggregates were adequately characterised. Human skin was less permeable than porcine skin, and the presence of UVA-R increased the C₆₀ content up to the dermis. © 2014 S. Karger AG, Basel.

  5. In vitro studies of morphological changes in enamel surface after Er:YAG and Nd:YAG laser irradiation, by SEM; Estudo in vitro do efeito do laser Nd:YAG e Er:YAG sobre o esmalte dental humano atraves de microscopia eletronica de varredura

    Energy Technology Data Exchange (ETDEWEB)

    Verlangieri, Eleonora Jaeger

    2001-07-01

    The caries prevention by using laser irradiation has been investigated by many authors using various lasers with different irradiations conditions. The purpose of this study was to investigated the morphological changes in enamel surface after Er:YAG and Nd:YAG laser irradiation, in vitro, by SEM. Fifteen freshly extracted, intact, caries-free, human third molars, were used in this study. The coronary portions were sectioned, from buccal to lingual direction, in two half-parts. Each one was irradiated by a different laser. The first one was irradiated with water-air spray, by a Nd:YAG laser, at 1.084 nm wave length, at 10 W, 10 Hz, 100 mJ for 60 sec., with an optical fiber in contact mode (0,32 mm of diameter); and the other half, with water-air spray by an Er:YAG laser at 2,94 micrometers wave length at the parameters of 4 Hz, 80 mJ, 24.95 J/cm{sup 2} for 60 sec. The results of this study suggested that both lasers promoted morphological changes in the enamel surface enhancing resistance and can be an alternative clinical method for caries preventions. (author)

  6. Gastrodia elata Blume Extract Modulates Antioxidant Activity and Ultraviolet A-Irradiated Skin Aging in Human Dermal Fibroblast Cells.

    Science.gov (United States)

    Song, Eunju; Chung, Haeyon; Shim, Eugene; Jeong, Jung-Ky; Han, Bok-Kyung; Choi, Hyuk-Joon; Hwang, Jinah

    2016-11-01

    Gastrodia elata Blume (GEB), a traditional herbal medicine, has been used to treat a wide range of neurological disorders (e.g., paralysis and stroke) and skin problems (e.g., atopic dermatitis and eczema) in oriental medicine. This study was designed to investigate the antioxidant ability of GEB and its antiaging effect on human dermal fibroblast cells (HDF). The total phenolic and flavonoid contents of GEB were 21.8 and 0.43 mg/g dry weight (DW), respectively. The ergothioneine content of GEB was 0.41 mg/mL DW. The DPPH and ABTS radical scavenging activities of GEB at 5 and 10 mg/mL approximately ranged between 31% and 44%. The superoxide dismutase activity of GEB at 10 and 25 mg/mL was 57% and 76%, respectively. GEB increased procollagen type 1 (PC1) production and inhibited matrix metalloproteinase-1 (MMP-1) production and elastase-1 activity in UVA-irradiated HDF. PC1 messenger RNA (mRNA) levels decreased upon UVA irradiation, but recovered in response to high doses of GEB in HDF. On the contrary, GEB significantly decreased MMP-1 and elastase-1 mRNA levels, which were markedly induced in UVA-irradiated HDF. Collectively, these results suggest that GEB has sufficient antioxidant ability to prevent the signs of skin aging in UVA-irradiated human skin cells, suggesting its potential as a natural antiaging product.

  7. Membrane lipid peroxidation by UV-A: Mechanism and implications

    Energy Technology Data Exchange (ETDEWEB)

    Bose, B.; Agarwal, S.; Chatterjee, S.N. (Saha Institute of Nuclear Physics, Calcutta (India))

    1990-10-01

    UV-A produced a dose-dependent linear increase of lipid peroxidation in liposomal membrane, as detected by the assay of (i) conjugated dienes, (ii) lipid hydroperoxides, (iii) malondialdehydes (MDA), and (iv) the fluorescent adducts formed by the reaction of MDA with glycine and also a linear dose-dependent increase of ({sup 14}C)glucose efflux from the liposomes. UV-A-induced MDA production could not be inhibited by any significant degree by sodium formate, dimethyl sulfoxide, EDTA, or superoxide dismutase but was very significantly inhibited by butylated hydroxytoluene, alpha-tocopherol, sodium azide, L-histidine, dimethylfuran, and beta-carotene. MDA formation increased with an increase in the D{sub 2}O content in water, leading to a maximal amount of nearly 50% enhancement of lipid peroxidation in 100% D{sub 2}O vis-a-vis water used as dispersion medium. The experimental findings indicate the involvement of singlet oxygen as the initiator of the UV-A-induced lipid peroxidation.

  8. [Corneal Cross-Linking with Riboflavin and UVA in Keratoconus].

    Science.gov (United States)

    Raiskup, F; Terai, N; Veliká, V; Spörl, E

    2016-08-01

    Changes in the biomechanical properties of the human cornea play an important role in the pathogenesis of corneal ectatic diseases. Many different pathological conditions in the cornea may reduce its biomechanical resistance. Corneal collagen cross-linking (CXL) has emerged as a promising technique to slow or even to stop the progression of ectasia. In this procedure, riboflavin (vitamin B2) is administered in conjunction with ultraviolet A light (UVA, 365 nm). This interaction causes the formation of reactive oxygen species, leading to additional covalent bonds between collagen molecules, with consequent biomechanical stiffening of the cornea. Although this method is not yet accepted as an evidence-based treatment of corneal ectasia, the results of prospective, randomised studies of CXL used in the treatment of this pathological entity show significant changes in the properties of corneal tissue. This procedure is currently the only aetiopathogenetic treatment of ectatic eyes that can delay or stop the process of cornea destabilisation, reducing the necessity for keratoplasty. Despite promising results, CXL is associated with issues that include long-term safety and duration of the stabilising effect. Georg Thieme Verlag KG Stuttgart · New York.

  9. Ultraviolet-A1 irradiation therapy for systemic lupus erythematosus

    Science.gov (United States)

    2017-01-01

    these mechanisms reduces levels of anticardiolipin antibodies and protects during lupus pregnancy. Capping all of this is that UV-A1 irradiation is an essentially innocuous, highly manageable, and comfortable therapeutic agency. PMID:28480786

  10. Food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    1987-02-28

    A brief article examines the controversy over food irradiation regarding the wholesomeness of irradiated food, its microbiological safety, loss of vitamins and changes in flavour. The benefits of food irradiation are also outlined including the destruction of certain food-borne pathogens and the prolongation of the shelf-life of food by killing pests and delaying the deterioration process.

  11. Cross-Linking Biomechanical Effect in Human Corneas by Same Energy, Different UV-A Fluence: An Enzymatic Digestion Comparative Evaluation.

    Science.gov (United States)

    Kanellopoulos, Anastasios J; Loukas, Yannis L; Asimellis, George

    2016-04-01

    To evaluate ex vivo the possible difference in corneal cross-linking (CXL) biomechanical effect of different ultraviolet-A (UV-A) irradiances. The study involved 25 human donor corneas, randomly allocated to 5 groups (n = 5 each). CXL was applied with UV-A irradiances of 3, 9, 18, 30, and 45 mW/cm2, maintaining equal cumulative energy dose of 5.4 J/cm2. UV-A was delivered on half of the cornea. The nonirradiated halves served as controls. Specimens were subjected to collagenase-A enzymatic digestion. The time to complete dissolution in each specimen was recorded. Time to dissolution in group-A (3 mW/cm2 for 30 minutes) was 321 ± 13.4 minutes (range: 300-330) compared with 171 ± 8.2 (range: 165-180) for their control. In group-B (9 mW/cm2 for 10 minutes), it was 282 ± 19.6 minutes (range: 270-315) compared with 177 ± 6.7 (165-180) for their control. In group-C (18 mW/cm2 for 5 minutes), it was 267 ± 19.6 minutes (range: 240-285) compared with 177 ± 7.7 (range: 165-180) for their control. In group-D (30 mW/cm2 for 3 minutes), it was 252 ± 12.5 minutes (range: 240-270) compared with 180 ± 10.6 minutes (range: 165-195) for their control. In group-E (45 mW/cm2 for 2 minutes), it was 204 ± 17.1 minutes (range: 180-225) compared with 186 ± 8.2 minutes (range: 180-195) for their control. The data in this ex vivo human corneal study indicate that the biomechanical effect of CXL studied by resistance to enzymatic digestion in human corneas is comparable between irradiances of 9, 18 and 30 mW/cm and seems to be reduced at a fluence of 45 mW/cm2.

  12. [Vitamins C and E protect cultures of bovine lens epithelium from the damaging effects of blue light (430 nm) and UVA light (300-400 nm)].

    Science.gov (United States)

    Mayer, U M; Müller, Y; Blüthner, K

    2001-02-01

    In 1992 Radlmaier showed that catalase can protect bovine lens epithelial cultures from blue light. The following experiments have the aim to examine, if vitamin C and E have protective functions, also. 367 cultures of bovine lens epithelial cells were incubated in Medium 199 added by 20% foetal calf serum FCS, by 125 I.U./ml penicillin, by 125 mg/ml Streptomycin, by 0.31 microgram/ml amphotericin B, by 2% L-Glutamin (200 mM), and by 1.25% Hepesbuffer. The incubation temperature was kept at 36 degrees C at a pCO2 of 5%. In order to avoid secondary morphologic alterations, we experimented only on the second to the third subculture. Light exposure followed three days after addition of the substances such as Cebion 500 (R) ad injection (6 mg/dl) and E-Vicotrat (R) ad injection (0.5 mg/dl). The blue light (420-430 nm, Draeger) was applied in a baby bed at 36 degrees C for four hours (1.1 mW/cm). The UV-A lamp was constructed and described by Heller [7]; at a wave length of 300-400 nm, the irradiation time was 10 minutes at 100 mW/cm2. In morphologic evaluation we looked for criteria such as cell diameter, cellular wall alterations, cellular inclusions and vacuoles. The cell count was done after staining with the vital dye trypan-blue in Neubauer's chamber. In statistic evaluation we used the pair comparison of Tuckey and Kruskall-Wallis-Test. After addition of 0.5 mg/ml vitamin E: In 89 cultures, morphologic evaluation and cell count showed a significant protection against light toxicity: After Uv-A-irradiation we counted 50% more living cells and after blue light 30% more. After addition of 6 mg/ml Cebion vitamin C: Morphologic evaluation and cell count of 223 cultures showed them also to be significantly protected: after irradiation by UV-A we counted 25% more and after exposition to blue light 15% more living cells. The demonstrated experiments significantly showed, that vitamin C and vitamin E can protect lens epithelial cultures from toxic stress by blue and by UV-A

  13. Evaluation of primary tooth enamel surface morphology and microhardness after Nd:YAG laser irradiation and APF gel treatment--an in vitro study.

    Science.gov (United States)

    Banda, Naveen Reddy; Vanaja Reddy, G; Shashikiran, N D

    2011-01-01

    Laser irradiation and fluoride has been used as a preventive tool to combat dental caries in permanent teeth, but little has been done for primary teeth which are more prone to caries. The purpose of this study was to evaluate microhardness alterations in the primary tooth enamel after Nd-YAG laser irradiation alone and combined with topical fluoride treatment either before or after Nd-YAG laser irradiation. Ten primary molars were sectioned and assigned randomly to: control group, Nd-YAG laser irradiation, Nd-YAG lasing before APF and APF followed by Nd-YAG lasing. The groups were evaluated for microhardness. Surface morphological changes were observed using SEM. Statistical comparisons were performed. The control group's SEM showed a relatively smooth enamel surface and lasing group had fine cracks and porosities. In the lasing + fluoride group a homogenous confluent surface was seen. In the fluoride + lasing group an irregular contour with marked crack propagation was noted. There was a significant increase in the microhardness of the treatment groups. Nd-YAG laser irradiation and combined APF treatment of the primary tooth enamel gave morphologically hardened enamel surface which can be a protective barrier against a cariogenic attack.

  14. [Effect of long-wave ultraviolet light (UV-A) and medium-wave ultraviolet rays (UV-B) on human skin. Critical comparison].

    Science.gov (United States)

    Raab, W

    1980-04-15

    When discussing the effects of ultraviolet radiation on human skin, one should carefully distinguish between the long wave ultraviolet light (UV-A) and the short wave radiations (UV-B and UV-C). Ultraviolet A induces immediate pigmentation but, if high energies are applied, a permanent pigmentation is elicited. This type of ultraviolet A-induced pigmentation has been called "spontaneous" pigmentation as no erythematous reaction is necessary to induce or accelerate melanine formation. Ultraviolet B provokes erythema and consecutive pigmentation. Upon chronic exposure, ultraviolet B causes the wellknown actinic damage of the skin and even provokes carcinoma. With exposures to the sunlight (global radiation), one should be most careful. The public must be informed extensively about the dangers of excessive sunbaths. The use of artificial "suns" with spectra between 260 and 400 nm is limited as it may cause the same type of damage as the global radiation. An exact schedule for use of artificial lamps is strongly recommended. After one cycle of exposures, an interruption is necessary until the next cycle of irradiations may start. Upon continual use for tanning of the skin, artificial lamps may provoke irreversible damage of the skin. Radiation sources with emission spectra of wavelengths between 315 and 400 nm exclusively are well suited for the induction of skin pigmentation (cosmetic use). Potent radiation such as UVASUN systems provoke a "pleasant" permanent pigmentation after exposures for less than one hour. The use of ultraviolet A (UV-A) does not carry any risk for the human skin.

  15. A broad spectrum high-SPF photostable sunscreen with a high UVA-PF can protect against cellular damage at high UV exposure doses.

    Science.gov (United States)

    Cole, Curtis; Appa, Yohini; Ou-Yang, Hao

    2014-08-01

    Advances in sunscreen technologies have yielded broad spectrum sunscreens at high-sun protection factor (SPF) and ultraviolet A protection factor (UVA-PF) levels that are photostable and powerful in protecting skin from erythema. Questions arise whether these sunscreens protect proportionally against cellular skin damage caused by high ultraviolet exposures. The objective of this study is to evaluate if high-SPF sunscreen can protect skin at a cellular level under UV exposure doses [>50 minimal erythema dose (MED)] similarly to the SPF value. Sunburn cells, Langerhans cells, thymine dimers, protein 53 (p53), and matrix metalloproteinase (MMP)-1 and MMP-9 endpoints were evaluated in biopsies from 12 subjects following four treatments: unprotected exposed to 0, 1 and 3 MED and sunscreen (SPF 55) protected exposed to 55 MED of UV radiation. All the markers showed significantly more damage for the 3 MED-untreated sites when compared with non-irradiated control, and majority of the markers showed marked damage following unprotected 1 MED exposure. After 55 MEDs, sunscreen-protected sites showed significantly less p53 and MMP-9 (keratinocyte) staining than the 1 MED-exposed unprotected sites, while all the other biomarkers in sunscreen protected sites showed no statistical differences from 1 MED-exposed unprotected sites. A high-SPF photostable sunscreen with high UVA-PF can provide proportionately high protection against multiple cellular damage markers. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Photo-pollution stress in skin: Traces of pollutants (PAH and particulate matter) impair redox homeostasis in keratinocytes exposed to UVA1.

    Science.gov (United States)

    Soeur, Jérémie; Belaïdi, Jean-Philippe; Chollet, Christel; Denat, Laurence; Dimitrov, Ariane; Jones, Christophe; Perez, Philippe; Zanini, Martine; Zobiri, Olivia; Mezzache, Sakina; Erdmann, Dominique; Lereaux, Guillaume; Eilstein, Joan; Marrot, Laurent

    2017-05-01

    It is likely that skin is exposed to low concentrations of pollutants such as Polycyclic Aromatic Hydrocarbons (PAH) either through topical penetration by ultrafine particles or by systemic distribution. No precise estimation of pollutants in living skin is available, but literature has reported contamination of blood by PAH at concentrations in the nanomolar range. Some pollutants (PAH for example) are photo-reactive and phototoxic: sunlight and pollution might thus synergistically compromise skin health. Here, the biological effects of particulate matter, PM extract and various PAH were compared in normal human epidermal keratinocytes (NHEK) and reconstructed skin model exposed to either daily UV (d-UV 300-400nm) or UVA1 (350-400nm). Impact of pollutants (PM, PAH or PM extract) combined to UV was studied on NHEK by measuring toxicity, redox homeostasis and GSH metabolism in NHEK. NHEK were exposed to UV from solar simulator (either d-UV or UVA1) combined with pollutants. Viability, clonogenic efficiency, redox homeostasis and GSH metabolism were assessed. Pollutants (PAH, PM or PM extract) ±UVA1 irradiation was associated with a significant phototoxic effect that was equal to or greater than that produced by d-UV. This result is interesting considering that UVA1 represents around 80% of daily UV and reaches the dermal-epidermal junction with ease. Moreover, among PAH studied, benzo[a]pyrene and indeno[1,2,3-cd]pyrene were phototoxic at very low concentrations (nanomolar range) on cultured cells or in reconstructed epidermis and also impaired keratinocyte clonogenic potential at sub-toxic doses. ROS generation within cells and in the inner mitochondrial compartment, mitochondrial membrane depolarization and/or reduced ATP production were also noted. Meanwhile, intracellular glutathione concentrations transiently decreased several hours post-treatment and reduction of its synthesis by buthionine sulfoximine potentiated PAH phototoxicity. Consequently, expression

  17. The in vitro immunogenic potential of caspase-3 proficient breast cancer cells with basal low immunogenicity is increased by hypofractionated irradiation.

    Science.gov (United States)

    Kötter, Bernhard; Frey, Benjamin; Winderl, Markus; Rubner, Yvonne; Scheithauer, Heike; Sieber, Renate; Fietkau, Rainer; Gaipl, Udo S

    2015-09-17

    Radiotherapy is an integral part of breast cancer treatment. Immune activating properties of especially hypofractionated irradiation are in the spotlight of clinicians, besides the well-known effects of radiotherapy on cell cycle and the reduction of the clonogenic potential of tumor cells. Especially combination of radiotherapy with further immune stimulation induces immune-mediated anti-tumor responses. We therefore examined whether hypofractionated irradiation alone or in combination with hyperthermia as immune stimulants is capable of inducing breast cancer cells with immunogenic potential. Clonogenic assay, AnnexinA5-FITC/Propidium iodide assay and ELISA analyses of heat shock protein 70 and high mobility group box 1 protein were applied to characterize colony forming capability, cell death induction, cell death forms and release of danger signals by breast cancer cells in response to hypofractionated radiation (4x4Gy, 6x3Gy) alone and in combination with hyperthermia (41.5 °C for 1 h). Caspase-3 deficient, hormone receptor positive, p53 wild type MCF-7 and caspase-3 intact, hormone receptor negative, p53 mutated MDA-MB231 breast cancer cells, the latter in absence or presence of the pan-caspase inhibitor zVAD-fmk, were used. Supernatants of the treated tumor cells were analyzed for their potential to alter the surface expression of activation markers on human-monocyte-derived dendritic cells. Irradiation reduced the clonogenicity of caspase deficient MCF-7 cells more than of MDA-B231 cells. In contrast, higher amounts of apoptotic and necrotic cells were induced in MDA-B231 cells after single irradiation with 4Gy, 10Gy, or 20Gy or after hypofractionated irradiation with 4x4Gy or 6x3Gy. MDA-B231 cells consecutively released higher amounts of Hsp70 and HMGB1 after hypofractionated irradiation. However, only the release of Hsp70 was further increased by hyperthermia. Both, apoptosis induction and release of the danger signals, was dependent on caspase-3. Only

  18. Hematotoxic and biochemical effects of UVA on the Egyptian toad (Bufo regularis).

    Science.gov (United States)

    Sayed, Alaa El-Din H

    2016-01-01

    To study the adverse impacts of ultraviolet radiation-A (UVA 320-400 nm) on some hematological and biochemical parameters of Bufo regularis was considered. Samples were classified into four groups: (i) Control; (ii) ultraviolet radiation (UVR)-treated group (for 3 days/for 15 min/day); (iii) UVR-treated group (for 3 days/for 30 min/day); and (iv) (for 3 days/for 60 min/day). The destructive effects of UVA radiation was evaluated by red blood cells (RBC) count, hemoglobin content (Hb), hematocrite (Ht), erythrocytic indices, white blood cells (WBC) count, total protein, glucose, aspartic amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), lactate dehyderogenase (LDH), glucose-6-phosphate dehyderogenase (G6PDH) and total bilribuin. No mortality was observed. However, some physiological effects after the exposure to UVA were reported. The UVA-induced malformations recorded in the red blood cells included crenated cells (Cr), Acanthocytes (Ac), tear drop-like cells (Tr) and sickle cells (Sk). The present study revealed the exposure to UVA from 15-60 min/day for three days could promote several biochemical and physiological disturbances as well as some changes in RBC.

  19. Outdoor solar UVA dose assessment with EBT2 radiochromic film using spectrophotometer and densitometer measurements.

    Science.gov (United States)

    Abukassem, I; Bero, M A

    2015-04-01

    Direct measurements of solar ultraviolet radiations (UVRs) have an important role in the protection of humans against UVR hazard. This work presents simple technique based on the application of EBT2 GAFCHROMIC(®) film for direct solar UVA dose assessment. It demonstrates the effects of different parts of the solar spectrum (UVB, visible and infrared) on performed UVA field measurements and presents the measurement uncertainty budget. The gradient of sunlight exposure level permitted the authors to establish the mathematical relationships between the measured solar UVA dose and two measured quantities: the first was the changes in spectral absorbance at the wavelength 633 nm (A633) and the second was the optical density (OD). The established standard relations were also applied to calculate the solar UVA dose variations during the whole day; 15 min of exposure each hour between 8:00 and 17:00 was recorded. Results show that both applied experimental methods, spectrophotometer absorbance and densitometer OD, deliver comparable figures for EBT2 solar UVA dose assessment with relative uncertainty of 11% for spectral absorbance measurements and 15% for OD measurements. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Photoprotective properties of the fluorescent europium complex in UV-irradiated skin.

    Science.gov (United States)

    Vogt, O; Lademann, J; Rancan, F; Meinke, M C; Schanzer, S; Stockfleth, E; Sterry, W; Lange-Asschenfeldt, B

    2013-01-01

    In this study, we compared the UV-protective abilities of the europium complex compared to titanium dioxide, which represents the most common physical filter for ultraviolet light in the broad-band spectral range. The UV absorption and light transformative capacities of the europium complex were evaluated using a spectrometer with a double-integrating sphere showing that the europium complex does not only absorb and reflect UV light, but transforms it into red and infrared light. It was found that the europium complex binds to the surface of Jurkat cells in vitro. Cells incubated with the europium complex showed a significantly higher viability after UVA and UVB irradiation as compared to untreated cells and cells incubated with titanium dioxide pointing out its photoprotective properties. The europium complex and titanium dioxide show similar penetration capacities into the stratum corneum as tested in human and porcine skin using tape stripping analysis. The europium complex has proved to be an efficient UV filter with a low cyto- and phototoxic profile and therefore represents a potential candidate for use in sunscreen formulations. Copyright © 2013 S. Karger AG, Basel.

  1. Minimal erythema response (MED to solar simulated irradiation in normal Indian skin

    Directory of Open Access Journals (Sweden)

    Mehta Rai Vandana

    2004-09-01

    Full Text Available BACKGROUND: Phototesting is an essential tool in the investigation of photodermatoses. AIMS: The main aim was to study the cutaneous response to UVR in terms of minimal erythema dose (MED to both UVA and UVB in normal Indian subjects with a solar simulator and to study the relationship of skin type to MED. METHODS: One hundred healthy volunteers not on any medication and without any history of photodermatoses were phototested using a solar simulator with whole spectrum irradiation (UVA, UVB and visible light and only visible and UVA radiation. The tested areas were marked with gentian violet and readings were taken after 24 hrs. RESULTS: Of the 100 volunteers, 48% were males and 52% were females, with a mean age of 36.6 ± 11.6 yrs. The most common skin type among Indians was type 5 (46% followed by type 4 (41%. The mean MED for UVB was 61.5 ± 17.25J/cm2. The MED for UVA could not be determined as none of the patients showed any erythema after irradiation for 45 minutes. CONCLUSIONS: As the MED is found to be low in idiopathic acquired photodermatoses, the MED in the normal population could serve as a baseline data in the investigation.

  2. Photostability study of commercial sunscreens submitted to artificial UV irradiation and/or fluorescent radiation.

    Science.gov (United States)

    Romanhole, Rodrigo Colina; Ataide, Janaina Artem; Cefali, Leticia Caramori; Moriel, Patricia; Mazzola, Priscila Gava

    2016-09-01

    Sunscreens contain molecules with the ability to absorb and/or reflect UVA (ultraviolet A) and UVB (ultraviolet B) radiation, thereby preventing this radiation from reaching the epidermis or dermis. Their photo stabilities after exposure to UV radiation are well known and described, but there is little data on the stability of these filters after fluorescent indoors light radiation, such as from light emitted by commercial lamps present in homes and offices. Those lamps can expose people to varying levels of UVB, UVA, visible light, and IR (infrared). This study assesses the photostability of four different commercial products containing chemical sun filters after artificial UV and fluorescent irradiation, correlating the UVB and UVA absorption efficiencies of each product against the different types of radiation. The tested products were applied on a plate of polymethylmethacrylate (PMMA) and irradiated by a solar simulator with specific filters for UVA and UVB and a commercial fluorescent light source. According to the results, three formulations did not show photostability, suffering significant changes in their UV absorption spectra, and one of the selected formulations can be considered photostable. This reinforces the importance of conducting stability studies for sunscreen formulations in different conditions, including under artificial (indoor) light exposure. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. In vitro assessment of the acid resistance of demineralized enamel irradiated with Er, Cr:YSGG and Nd:YAG lasers.

    Science.gov (United States)

    Santos, Diones M; Nogueira, Ruchele D; Lepri, Cesar P; Gonçalves, Luciano S; Palma-Dibb, Regina G; Geraldo-Martins, Vinícius R

    2014-01-01

    This study's purpose was to evaluate the acid resistance of demineralized enamel irradiated with high-intensity lasers. Enamel fragments were demineralized and treated as follows (N=10): Group 1-no treatment; Group 2-five percent sodium fluoride (NaF) varnish; Group 3-Er, Cr:YSGG laser (8.92 J/cm2, 0.5 W, 20 Hz, 30 seconds); Group 4-NaF and Er, Cr:YSGG laser; Group 5-Er, Cr:YSGG laser and NaF; Group 6-Nd:YAG laser (84.9 J/cm2, 0.5 W, 10 Hz, 30 seconds); Group 7-NaF and Nd:YAG laser; and Group 8-Nd:YAG laser and NaF. The samples were subjected to pH-cycling and assessed by microhardness (analysis of variance; α equals five percent) at different depths from the outer enamel surface. Samples were observed using polarized light microscopy (PLM) and scanning electron microscopy (SEM). There were no significant differences among the experimental groups in any of the subsurface layers evaluated. PLM observation revealed that the extent of demineralization of the irradiated samples was similar to the samples for Group 1 (control). SEM observation showed that irradiated surfaces were ablated and presented areas of melting. Laser irradiation, with or without applying five percent sodium fluoride, was not capable of increasing the enamel white spot lesions' acid resistance.

  4. The effect of solar irradiated Vibrio cholera on the secretion of pro-inflammatory cytokines and chemokines by the JAWS II dendritic cell line in vitro

    CSIR Research Space (South Africa)

    Ssemakalu, CC

    2015-06-01

    Full Text Available the dendritic cells. The profile of cy- tokines and chemokines secreted by the dendritic cells in response to solar irradiated cells would most likely elicit a Th2 immune response. However, mixed leukocyte assays as well as in vivo studies are required to show...

  5. Comparison of ultraviolet A light protection standards in the United States and European Union through in vitro measurements of commercially available sunscreens.

    Science.gov (United States)

    Wang, Steven Q; Xu, Haoming; Stanfield, Joseph W; Osterwalder, Uli; Herzog, Bernd

    2017-07-01

    The importance of adequate ultraviolet A light (UVA) protection has become apparent in recent years. The United States and Europe have different standards for assessing UVA protection in sunscreen products. We sought to measure the in vitro critical wavelength (CW) and UVA protection factor (PF) of commercially available US sunscreen products and see if they meet standards set by the United States and the European Union. Twenty sunscreen products with sun protection factors ranging from 15 to 100+ were analyzed. Two in vitro UVA protection tests were conducted in accordance with the 2011 US Food and Drug Administration final rule and the 2012 International Organization for Standardization method for sunscreen effectiveness testing. The CW of the tested sunscreens ranged from 367 to 382 nm, and the UVA PF of the products ranged from 6.1 to 32. Nineteen of 20 sunscreens (95%) met the US requirement of CW >370 nm. Eleven of 20 sunscreens (55%) met the EU desired ratio of UVA PF/SPF > 1:3. The study only evaluated a small number of sunscreen products. The majority of tested sunscreens offered adequate UVA protection according to US Food and Drug Administration guidelines for broad-spectrum status, but almost half of the sunscreens tested did not pass standards set in the European Union. Copyright © 2017. Published by Elsevier Inc.

  6. Radiation cross-linked carboxymethyl sago pulp hydrogels loaded with ciprofloxacin: Influence of irradiation on gel fraction, entrapped drug and in vitro release

    Science.gov (United States)

    Lam, Yi Lyn; Muniyandy, Saravanan; Kamaruddin, Hashim; Mansor, Ahmad; Janarthanan, Pushpamalar

    2015-01-01

    Carboxymethyl sago pulp (CMSP) with 0.4 DS, viscosity 184 dl/g and molecular weight 76,000 g/mol was synthesized from sago waste. 10 and 20% w/v solutions of CMSP were irradiated at 10-30 kGy to form hydrogels and were characterized by % gel fraction (GF). Irradiation of 20% CMSP using 25 kGy has produced stable hydrogels with the highest % GF and hence loaded with ciprofloxacin HCl. Drug-loaded hydrogels were produced by irradiating the mixture of drug and 20% CMSP solution at 25 kGy. After irradiation, the hydrogels were cut into circular discs with a diameter of 6±1 mm and evaluated for physicochemical properties as well as drug release kinetics. The ciprofloxacin loading in the disc was 14.7%±1 w/w with an entrapment efficiency of 73.5% w/w. The low standard deviation of drug-loaded discs indicated uniform thickness (1.5±0.3 mm). The unloaded discs were thinner (1±0.4 mm) and more brittle than the drug-loaded discs. FESEM, FT-IR, XRD, DSC and TGA analysis revealed the absence of polymer-drug interaction and transformation of crystalline to amorphous form of ciprofloxacin in the discs. The disc sustained the drug release in phosphate buffer pH 7.4 over 36 h in a first-order manner. The mechanism of the drug release was found to be swelling controlled diffusion and matrix erosion. The anti-bacterial effect of ciprofloxacin was retained after irradiation and CMSP disc could be a promising device for ocular drug delivery.

  7. Quantifying solar spectral irradiance in aquatic habitats for the assessment of photoenhanced toxicity

    Science.gov (United States)

    Barron, M.G.; Little, E.E.; Calfee, R.; Diamond, S.

    2000-01-01

    The spectra and intensity of solar radiation (solar spectral irradiance [SSI]) was quantified in selected aquatic habitats in the vicinity of an oil field on the California coast. Solar spectral irradiance measurements consisted of spectral scans (280–700 nm) and radiometric measurements of ultraviolet (UV): UVB (280–320 nm) and UVA (320–400 nm). Solar spectral irradiance measurements were taken at the surface and at various depths in two marsh ponds, a shallow wetland, an estuary lagoon, and the intertidal area of a high-energy sandy beach. Daily fluctuation in SSI showed a general parabolic relationship with time; maximum structure–activity relationship (SAR) was observed at approximate solar noon. Solar spectral irradiance measurements taken at 10-cm depth at approximate solar noon in multiple aquatic habitats exhibited only a twofold variation in visible light and UVA and a 4.5-fold variation in UVB. Visible light ranged from 11,000 to 19,000 μW/cm2, UVA ranged from 460 to 1,100 μW/cm2, and UVB ranged from 8.4 to 38 μW/cm2. In each habitat, the attenuation of light intensity with increasing water depth was differentially affected over specific wavelengths of SSI. The study results allowed the development of environmentally realistic light regimes necessary for photoenhanced toxicity studies.

  8. Riboflavin and ultraviolet A irradiation for the prevention of progressive myopia in a guinea pig model.

    Science.gov (United States)

    Li, Xiaoxia; Wu, Miaoqin; Zhang, Luyi; Liu, Hui; Zhang, Lan; He, Jinjing

    2017-12-01

    In this study, we evaluated the effect of oral administration of riboflavin combined with whole-body ultraviolet A (UVA) irradiation on the biochemical and biomechanical properties of sclera in a guinea pig model to control the progression of myopia. Experimental groups were administered 0.1% riboflavin solution with or without vitamin C by gavage from 3 days before myopic modeling and during the modeling process. Guinea pigs underwent 30 min of whole-body UVA irradiation after each gavage for 2 weeks. For control groups, guinea pigs were administered vitamin C and underwent either whole-body UVA irradiation without 0.1% riboflavin solution or whole-body fluorescent lamp irradiation with or without 0.1% riboflavin solution. Resultantly, myopia models were established with an increased axial length and myopic diopter. Compared with myopic eyes in the control groups, the net increase in axial length, diopter and strain assessment decreased significantly, and the net decrease in sclera thickness, ultimate load, and stress assessment decreased significantly in experimental groups. MMP-2 expression showed a lower net increase, while TIMP-2 expression showed a lower net decrease. In addition, hyperplasia of scleral fibroblasts was more active in myopic eyes of experimental groups. Overall, our results showed that oral administration of riboflavin with whole-body UVA irradiation could increase the strength and stiffness of sclera by altering the biochemical and biomechanical properties, and decreases in axial elongation and myopic diopter are greater in the guinea pig myopic model. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Assessment of the bacteria reduction in the infected root canal irradiated with diode laser; Avaliacao da reducao bacteriana em conduto radicular infectado e irradiado com laser de diodo. Estudo in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Radaelli, Claudia Amaral Rabello de Mello

    2002-07-01

    High success rates are achieved in conventional endodontic treatment of vital pulp teeth. However, in cases of non-vital pulp, a decrease in the rate of success occurs due to difficulties in achieving a complete disinfection of the root canals system. Some bacteria, such as Enterococcus faecalis, are frequently found in cases of endodontic treatment failure due to their high resistance to the conventional endodontic treatment. The aim of this study was to evaluate the efficiency of a high power diode laser irradiation in bacterial reduction of contaminated canals associated with dressing compose by calcium hydroxide paste propylene glycol and camphorated paramonochlorophenol. Eighty-two root canals were infected in vitro with Enterococcus faecalis in a concentration of 1x10{sup 8} CFU/ml. Specimens were high intensity irradiated with a diode laser model Opus 10, at a wavelength of 830 nm. Two different parameters were employed in continuous mode: 3 W and 2,5 W with a 360 {mu}m optical fiber at an angle of approximately 5 degrees respect to the dentine surface during 5 seconds, in 4 applications, with 20 seconds intervals among them. After these proceedings specimens were vortexed in peptone water and dilutions performed. Aliquots of the dilution were plated on m-Enterococcus agar, incubated, and the Colonies Forming Units (CFU) of ali groups was counted. The results showed a significant reduction of bacteria on ali groups after laser irradiation. A high reduction rate was achieved: 98.5% immediately after the laser irradiation; 48 hours after, the reduction was of 96,73% and, finally, a 100% reduction was achieved through the combination of laser irradiation and a long lasting dressing of calcium hydroxide paste, propylene glycol and camphorated paramonochlorophenol. High rates of bacteria reduction were achieved using the parameter of 3 W in continuous mode with the power of 2,9473 KW/cm{sup 2}. The temperature was monitored with a K-pipe thermocouple placed at

  10. Assessment of oxidative stress in the planktonic diatom Thalassiosira pseudonana in response to UVA and UVB radiation

    NARCIS (Netherlands)

    Rijstenbil, J.W.

    2002-01-01

    Induction of oxidative stress by UVA and UVB in the diatom Thalassiosira pseudonana was experimentally studied. Cells, pre-grown in a light-limited continuous culture, were incubated for 4 h at 175 µmol m-2s-1photosynthetically active radiation, with optional supplementary UVA at an unweighted dose

  11. Extracellular Polysaccharide Production in a Scytonemin-Deficient Mutant of Nostoc punctiforme Under UVA and Oxidative Stress.

    Science.gov (United States)

    Soule, Tanya; Shipe, Dexter; Lothamer, Justin

    2016-10-01

    Some cyanobacteria can protect themselves from ultraviolet radiation by producing sunscreen pigments. In particular, the sheath pigment scytonemin protects cells against long-wavelength UVA radiation and is only found in cyanobacteria which are capable of extracellular polysaccharide (EPS) production. The presence of a putative glycosyltransferase encoded within the scytonemin gene cluster, along with the localization of scytonemin and EPS to the extracellular sheath, prompted us to investigate the relationship between scytonemin and EPS production under UVA stress. In this study, it was hypothesized that there would be a relationship between the biosynthesis of scytonemin and EPS under both UVA and oxidative stress, since the latter is a by-product of UVA radiation. EPS production was measured following exposure of wild-type Nostoc punctiforme and the non-scytonemin-producing strain SCY59 to UVA and oxidative stress. Under UVA, SCY59 produced significantly more EPS than the unstressed controls and the wild type, while both strains produced more EPS under oxidative stress compared to the controls. The results suggest that EPS secretion occurs in response to the oxidative stress by-product of UVA rather than as a direct response to UVA radiation.

  12. Rutin as a Mediator of Lipid Metabolism and Cellular Signaling Pathways Interactions in Fibroblasts Altered by UVA and UVB Radiation

    Directory of Open Access Journals (Sweden)

    Agnieszka Gęgotek

    2017-01-01

    Full Text Available Background. Rutin is a natural nutraceutical that is a promising compound for the prevention of UV-induced metabolic changes in skin cells. The aim of this study was to examine the effects of rutin on redox and endocannabinoid systems, as well as proinflammatory and proapoptotic processes, in UV-irradiated fibroblasts. Methods. Fibroblasts exposed to UVA and UVB radiation were treated with rutin. The activities and levels of oxidants/antioxidants and endocannabinoid system components, as well as lipid, DNA, and protein oxidation products, and the proinflammatory and pro/antiapoptotic proteins expression were measured. Results. Rutin reduced UV-induced proinflammatory response and ROS generation and enhanced the activity/levels of antioxidants (SOD, GSH-Px, vitamin E, GSH, and Trx. Rutin also normalized UV-induced Nrf2 expression. Its biological activity prevented changes in the levels of the lipid mediators: MDA, 4-HNE, and endocannabinoids, as well as the endocannabinoid receptors CB1/2, VR1, and GPR55 expression. Furthermore, rutin prevented the protein modifications (tyrosine derivatives formation in particular and decreased the levels of the proapoptotic markers—caspase-3 and cytochrome c. Conclusion. Rutin prevents UV-induced inflammation and redox imbalance at protein and transcriptional level which favors lipid, protein, and DNA protection. In consequence rutin regulates endocannabinoid system and apoptotic balance.

  13. Corneal biomechanical properties at different corneal cross-linking (CXL) irradiances.

    Science.gov (United States)

    Hammer, Arthur; Richoz, Olivier; Arba Mosquera, Samuel; Tabibian, David; Hoogewoud, Florence; Hafezi, Farhad

    2014-05-02

    New corneal cross-linking (CXL) devices are capable of using higher UV-A light irradiances than used in original CXL protocols. The Bunsen-Roscoe law states that a photochemical reaction should stay constant if the delivered total energy is kept constant; however, little clinical data are available to support this hypothesis. We investigated the biomechanical properties of four groups (n = 50 each) of porcine corneas. Three groups were exposed to riboflavin 0.1 % and UV-A irradiation of equal total energy (3 mW/cm(2) for 30 minutes, 9 mW/cm(2) for 10 minutes, and 18 mW/cm(2) for 5 minutes). Controls were exposed to riboflavin 0.1% without irradiation. Young's modulus of 5-mm wide corneal strips was used as an indicator of corneal stiffness. We observed a decreased stiffening effect with increasing UV-A intensity. Young's modulus at 10% strain showed significant differences between 3 mW/cm(2) and 9 mW/cm(2) (P = 0.002), 3 mW/cm(2) and 18 mW/cm(2) (P = 0.0002), 3 mW/cm(2) and the control group (P biomechanical effect of CXL decreased significantly when using high irradiance/short irradiation time settings. Intrastromal oxygen diffusion capacity and increased oxygen consumption associated with higher irradiances may be a limiting factor leading to reduced treatment efficiency. Our results regarding the efficiency of high-irradiance collagen cross-linking (CXL) raise concerns about the clinical efficiency of the new high-irradiance CXL devices already used in clinical practice without proper validation.

  14. Extracción y determinación de aromas en orujos de uva

    OpenAIRE

    Frago Ramos, Sara

    2016-01-01

    Los orujos de uva son los principales subproductos generados en la vinificación. Existen diversas vías de valorización de estos residuos, destacando la extracción de polifenoles. Sin embargo, no se ha estudiado su composición aromática y las posibilidades de su recuperación. Con el fin de determinar el potencial aromático en orujos de uva de variedades tintas, se ha llevado a cabo un procedimiento experimental basado en una extracción verde empleando disoluciones acuosas y un a...

  15. In vitro study of morphological and chemical modification threshold of bovine dental enamel irradiated by the holmium laser; Estudo in vitro das alteracoes morfologicas e quimicas do esmalte dental bovino irradiado pelo laser de holmio

    Energy Technology Data Exchange (ETDEWEB)

    Eduardo, Patricia Lerro de Paula

    2001-07-01

    The aim of this study is to investigate the Ho:YLF laser effects on the dental enamel surface with regards to its morphology, thermal variations during its irradiation in the pulp chamber and its increased resistance to demineralization through quantitative analysis of calcium and phosphorous atoms reactive concentrations in samples. Twenty samples of bovine enamel were used and divided in four groups: control - acidulated phosphate fluoride (APF) application followed by demineralization treatment with lactic acid; irradiation with Ho:YLF laser (100 J/cm{sup 2}) followed by APF topic application and demineralization treatment with lactic acid; irradiation with Ho:YLF laser (350 J/cm{sup 2}) followed by APF topic application and demineralization treatment with lactic acid: and irradiation with Ho:YLF laser ( 450 J/cm{sup 2}) followed by APF topic application and demineralization treatment with lactic acid. Ali samples were quantified according to their calcium and phosphorous atoms relative concentrations before and after the treatments above. X-Ray fluorescence spectrochemical analysis and scanning electron microscopy were carried out. It was observed an increase on the calcium and phosphorous atoms concentration ratio and therefore the enamel demineralization reduction as a result of the lactic acid treatment in the samples irradiated with the holmium laser followed by the APF application. In order to evaluate the feasibility of this study for clinical purposes, morphological changes caused by the holmium laser irradiation were analyzed. Such modifications were characterized by melted and re-solidified regions of the enamel with consequent changes on its permeability and solubility. Temperature changes of ten human pre-molars teeth irradiated with 350 J/cm{sup 2} and 450 J/cm{sup 2} were also monitored in the pulp chamber in real time. Temperature increases over 4,20 C did not occur. The results obtained from this study along with the results from previous

  16. Influence of the angle of irradiation of the Er,Cr:YSGG laser on the morphology, attachment of blood components, roughness, and root wear: in vitro study.

    Science.gov (United States)

    de Oliveira, Guilherme José Pimentel Lopes; Pavone, Chaine; Sampaio, José Eduardo Cézar; Marcantonio, Rosemary Adriana Chiérici

    2010-11-01

    To evaluate the influence of the working tip angulation of the Er,Cr:YSGG laser on the morphology, attachment of blood components, roughness, and wear on irradiated root surfaces compared to scaling and root planing (SRP). The present study used 45 teeth, of which 25 were used for the analysis of the morphology and the attachment of blood components and 20 were used for the analysis of the roughness and of the root wear. The teeth were randomly divided into five groups according to the treatment applied: (G1) Laser Er,Cr:YSGG-30°; (G2) Laser Er,Cr:YSGG-45°; (G3) Laser Er,Cr:YSGG-60°; (G4) Laser Er,Cr:YSGG-90°; and (G5) SRP. The root surfaces irradiated with the Er,Cr:YSGG laser working angulation tip of 45° and 60°, and the samples scaled with manual instruments presented greater attachment of blood components than the group where the Er,Cr:YSGG laser irradiated at working tip angulation of 30° and 90° (Pirradiated with the Er,Cr:YSGG laser were rougher than the samples scaled with manual instruments (Pirradiated with the Er,Cr:YSGG laser at an angle of 30° presented the least wear in comparison to all the other treatments (Pirradiated root surfaces proved to be rougher than those scaled with manual instruments; however, irradiation at working tip angulations of 45° and 60° produced results of attachment of blood components and root wear comparable with those obtained with manual instrumentation. © 2010 Wiley-Liss, Inc.

  17. Comparison of Radiation-Induced Bystander Effect in QU-DB Cells after Acute and Fractionated Irradiation: An In Vitro Study.

    Science.gov (United States)

    Soleymanifard, Shokouhozaman; Bahreyni Toossi, Mohammad Taghi; Kamran Samani, Roghayeh; Mohebbi, Shokoufeh

    2016-01-01

    Radiation effects induced in non-irradiated cells are termed radiation-induced bystander effects (RIBE). The present study intends to examine the RIBE response of QU-DB bystander cells to first, second and third radiation fractions and compare their cumulative outcome with an equal, single acute dose. This experimental study irradiated three groups of target cells for one, two and three times with(60)Co gamma rays. One hour after irradiation, we transferred their culture media to non-irradiated (bystander) cells. We used the cytokinesis block micronucleus assay to evaluate RIBE response in the bystander cells. The numbers of micronuclei generated in bystander cells were determined. RIBE response to single acute doses increased up to 4 Gy, then decreased, and finally at the 8 Gy dose disappeared. The second and third fractions induced RIBE in bystander cells, except when RIBE reached to the maximum level at the first fraction. We split the 4 Gy acute dose into two fractions, which decreased the RIBE response. However, fractionation of 6 Gy (into two fractions of 3 Gy or three fractions of 2 Gy) had no effect on RIBE response. When we split the 8 Gy acute dose into two fractions we observed RIBE, which had disappeared following the single 8 Gy dose. The impact of dose fractionation on RIBE induced in QU-DB cells de- pended on the RIBE dose-response relationship. Where RIBE increased proportion- ally with the dose, fractionation reduced the RIBE response. In contrast, at high dos- es where RIBE decreased proportionally with the dose, fractionation either did not change RIBE (at 6 Gy) or increased it (at 8 Gy).

  18. Insight into photocatalytic degradation of dissolved organic matter in UVA/TiO₂ systems revealed by fluorescence EEM-PARAFAC.

    Science.gov (United States)

    Phong, Diep Dinh; Hur, Jin

    2015-12-15

    Photocatalytic degradation of dissolved organic matter (DOM) using TiO2 as a catalyst and UVA as a light source was examined under various experimental settings with different TiO2 doses, solution pH, and the light intensities. The changes in UV absorbance and fluorescence with the irradiation time followed a pseudo-first order model much better than those of dissolved organic carbon. In general, the degradation rates were increased by higher TiO2 doses and light intensities. However, the exact photocatalytic responses of DOM to the irradiation were affected by many other factors such as aggregation of TiO2, light scattering, hydroxyl radicals produced, and DOM sorption on TiO2. Fluorescence excitation-emission matrix (EEM) coupled with parallel factor analysis (PARAFAC) revealed that the DOM changes in fluorescence could be described by the combinations of four dissimilar components including one protein-like, two humic-like, and one terrestrial humic-like components, each of which followed well the pseudo-first order model. The photocatalytic degradation rates were higher for protein-like versus humic-like component, whereas the opposite order was displayed for the degradation rates in the absence of TiO2, suggesting different dominant mechanisms operating between the systems with and without TiO2. Our results based on EEM-PARAFAC provided new insights into the underlying mechanisms associated with the photocatalytic degradation of DOM as well as the potential environmental impact of the treated water. This study demonstrated a successful application of EEM-PARAFAC for photocatalytic systems via directly comparing the kinetic rates of the individual DOM components with different compositions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Transformation products formation of ciprofloxacin in UVA/LED and UVA/LED/TiO2 systems: Impact of natural organic matter characteristics.

    Science.gov (United States)

    Li, Si; Hu, Jiangyong

    2018-04-01

    The role of natural organic matter (NOM) in contaminants removal by photolysis and photocatalysis has aroused increasing interest. However, evaluation of the influence of NOM characteristics on the transformation products (TPs) formation and transformation pathways of contaminants has rarely been performed. This study investigated the decomposition kinetics, mineralization, TPs formation and transformation pathways of antibiotic ciprofloxacin (CIP) during photolysis and photocatalysis in the presence of three commercial NOM isolates (Sigma-Aldrich humic acid (SAHA), Suwannee River humic acid (SRHA) and Suwannee River NOM (SRNOM)) by using UVA light emitting diode (UVA/LED) as an alternative light source. NOM isolates insignificantly affected CIP photolysis but strongly inhibited CIP photocatalysis due to competitive radical quenching. The inhibitory effect followed the order of SAHA (49.6%) > SRHA (29.9%) > SRNOM (21.2%), consistent with their •OH quenching abilities, SUVA254 values and orders of aromaticity. Mineralization rates as revealed by F- release were negatively affected by NOM during CIP photocatalysis. TPs arising from hydroxylation and defluorination were generally suppressed by NOM isolates in UVA/LED and UVA/LED/TiO2 systems. In contrast, dealkylation and oxidation of piperazine ring were promoted by NOM. The enhancement in the apparent formation kinetics (kapp) of TP245, TP291, TP334a, TP334b and TP362 followed the order of SRNOM > SRHA > SAHA. kapp values were positively correlated with O/C ratio, carboxyl content, E2/E3 and fluorescence index (FI) of NOM and negatively related with SUVA254 values. The observed correlations indicate that NOM properties are important in determining the fate and transformation of organic contaminants during photolysis and photocatalysis. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Combined effect of gamma irradiation methods and in vitro explant sources on mutation induction of flower color in Chrysanthemum morifoliun Ramat

    Energy Technology Data Exchange (ETDEWEB)

    Nagatomi, Shigeki [Inst. of Radiation Breeding, Omiya, Ibaraki (Japan); Miyahira, Eiken; Degi, Konosuke

    1997-11-01

    Effective radiation breeding method was searched by establishing an effective exposure method to induce a mutation involved in flower color of chrysanthemum and clarifying the effects of its combined use with cultured explants. A chrysanthemum `Taihei`, a variety suitable for cut-flower use was used as the subject, which was irradiated at a dose ranging from 0.25-1.5 Gy/day for 20 days. The floral petals, buds and leaves were used as the explants for callus induction culture. The flower color was evaluated using Japanese Standard Color chart for Horticultural Plants. The color spectrum of the adaxial surface of a petal was recorded by spectro-photometer TC-1800 MK-2. Thus, six mutants of flower color were registered as new varieties. Either of these mutants was derived from chronic irradiation. Three varieties from petal culture, two from bud one and one from cutting culture were obtained, showing that the combined method of chronic irradiation and organ culture is useful in practice for mutation breeding of flower species. Further, this method is applicable for production of non-chimeric mutants, enhancement of the mutation rate and widening the mutation spectra in vegetatively propagated plants. (M.N.)

  1. Energy output reduction and surface alteration of quartz tips following Er:YAG laser contact irradiation on soft and hard tissues in vitro.

    Science.gov (United States)

    Lin, Taichen; Kawamura, Rie; Aoki, Akira; Ichinose, Shizuko; Mizutani, Koji; Taniguchi, Yoichi; Eguro, Toru; Saito, Norihito; Izumi, Yuichi

    2016-01-01

    Though the Er:YAG laser (ErL) has been used in periodontal therapy, the irradiated tip damage has not been studied in detail. In this study, the change in the energy output, surface morphology, and temperature of quartz tips was evaluated following contact irradiation. Soft tissue, calculus on extracted human teeth, and porcine bone were irradiated by ErL for 60 min at 14.2 or 28.3 J/cm(2)/pulse and 20 Hz with or without water spray. The energy output ratio declined the most in the calculus group, followed by the bone and soft tissue groups with and/or without water spray. Carbon contamination was detected in all groups, and contamination by P, Ca, and/or other inorganic elements was observed in the calculus and bone groups. The rate of energy output reduction and the degree of surface alteration/contamination is variously influenced by the targeting tissue, temperature elevation of the tip and water spray.

  2. Nutrient limitation and high irradiance acclimation reduce PAR and UV-induced viability loss in the Antarctic diatom Chaetoceros brevis (Bacillariophyceae)

    NARCIS (Netherlands)

    van de Poll, WH; van Leeuwe, MA; Roggeveld, J; Buma, AGJ

    The effects of high PAR (400-700 nm), UVA (315-400 nm), and UVB (280-315 nm) radiation on viability and photosynthesis were investigated for Chaetoceros brevis Schutt. This Antarctic marine diatom was cultivated under low, medium, and high irradiance and nitrate, phosphate, silicate, and iron

  3. Modifications in stromal extracellular matrix of aged corneas can be induced by ultraviolet A irradiation.

    Science.gov (United States)

    Gendron, Sébastien P; Rochette, Patrick J

    2015-06-01

    With age, structural and functional changes can be observed in human cornea. Some studies have shown a loss of corneal transparency and an increase in turbidity associated with aging. These changes are caused by modifications in the composition and arrangement of extracellular matrix in the corneal stroma. In human skin, it is well documented that exposure to solar radiation, and mainly to the UVA wavelengths, leads to phenotypes of photoaging characterized by alteration in extracellular matrix of the dermis. Although the cornea is also exposed to solar radiation, the extracellular matrix modifications observed in aging corneas have been mainly attributed to chronological aging and not to solar exposure. To ascertain the real implication of UVA exposure in extracellular matrix changes observed with age in human cornea, we have developed a model of photoaging by chronically exposing corneal stroma keratocytes with a precise UVA irradiation protocol. Using this model, we have analyzed UVA-induced transcriptomic and proteomic changes in corneal stroma. Our results show that cumulative UVA exposure causes changes in extracellular matrix that are found in corneal stromas of aged individuals, suggesting that solar exposure catalyzes corneal aging. Indeed, we observe a downregulation of collagen and proteoglycan gene expression and a reduction in proteoglycan production and secretion in response to cumulative UVA exposure. This study provides the first evidence that chronic ocular exposure to sunlight affects extracellular matrix composition and thus plays a role in corneal changes observed with age. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  4. Ultraviolet spectral distribution and erythema-weighted irradiance from indoor tanning devices compared with solar radiation exposures.

    Science.gov (United States)

    Sola, Yolanda; Baeza, David; Gómez, Miguel; Lorente, Jerónimo

    2016-08-01

    Concern regarding the impact of indoor tanning devices on human health has led to different regulations and recommendations, which set limits on erythema-weighted irradiance. Here, we analyze spectral emissions from 52 tanning devices in Spanish facilities and compare them with surface solar irradiance for different solar zenith angles. Whereas most of the devices emitted less UV-B radiation than the midday summer sun, the unweighted UV-A irradiance was 2-6 times higher than solar radiation. Moreover, the spectral distributions of indoor devices were completely different from that of solar radiation, differing in one order of magnitude at some UV-A wavelengths, depending on the lamp characteristics. In 21% of the devices tested, the erythema-weighted irradiance exceeded 0.3Wm(-2): the limit fixed by the European standard and the Spanish regulation. Moreover, 29% of the devices fall within the UV type 4 classification, for which medical advice is required. The high variability in erythema-weighted irradiance results in a wide range of exposure times to reach 1 standard erythemal dose (SED: 100Jm(-2)), with 62% of devices requiring exposures of solar UV-A dose. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Irradiation damage

    Energy Technology Data Exchange (ETDEWEB)

    Howe, L.M

    2000-07-01

    There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization.

  6. In vitro assessment of the composition and microhardness of hard tissues of oral cavity submitted to gamma irradiation; Avaliacao in vitro da composicao e microdureza dos tecidos duros da cavidade bucal submetidos a irradiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Paredes, Wilber Edison Bernaola

    2017-11-01

    Clinical Radiotherapy is extremely important for the treatment of malignant lesions of the head and neck region, however, exposure to ionizing radiation can lead to systemic or local complications during and after radiation treatment. Among these immediate local complications are the oral cavity xerostomia and the consequent oral mucositis. Regarding late complications produced by radiation, tooth decay of radiation and osteoradionecrosis are included, which are considered dose-dependent lesions, with high incidence in recent decades and difficult to manage, although these appear after completion of treatment and under the influence of local factors. The methodology proposed in this study consists in evaluating the effect of gamma radiation after irradiation of the samples, using the dose used in patients suffering with head and neck cancer. The samples were obtained from human enamel and root dentin; and swine mandibular bone, which were previously polished, and then submitted to the analysis of the initial surface microhardness of all groups. Subsequently, the samples were irradiated in a dose rate of 4 Gy per day, completing a total dose of 72 Gy. Finally, the samples were submitted to surface microhardness analysis after irradiation, which presented statistically significant results from the Student t, ANOVA and Tukey statistical tests referred to the difference of the mean of the initial and final values of each study group with a significant value of p = 0.00 (<0.05). Regarding the morphological analysis in scanning electron microscopy (SEM), the deleterious effect of gamma irradiation was evidenced as structural cracks, breaks and superficial fractures of the analyzed tissues and the biochemical analysis by Attenuated Total Reflection technique using Fourier transform infrared spectroscopy (ATR - FTIR) showed degradation of inorganic components and denaturation of organic compounds; whereby, the effect of gamma irradiation on the hard tissues of the oral

  7. Convenient Synthesis of a Novel Flavonoid with Extended π-System: Active Agent for UVA Protection

    Directory of Open Access Journals (Sweden)

    Saleh Al-Busafi

    2013-01-01

    Full Text Available Flavonoid derivative with extended cinnamic acid moiety was synthesized using Baker-Venkataraman reaction. The compound shows interesting UV absorption properties which make it a good UVA absorber. A bathochromic shift of 18 nm was observed when the size of cinnamic acid segment was increased by one styrylogous extension.

  8. IBIS UvA: Combining theory and practice in the area of quality and efficiency improvement

    NARCIS (Netherlands)

    Schoonhoven, M.

    2012-01-01

    The institute for Business and Industrial Statistics of the University of Amsterdam (IBIS UvA) is an independent consultancy firm. The institute sees the interaction between scientific research, on the one hand, and the application of technology in business and healthcare, on the other, as its core.

  9. Comparison of the effects of UV-A radiation on Leptospira interrogan ...

    African Journals Online (AJOL)

    USER

    2010-05-24

    May 24, 2010 ... Interestingly, Cullen and co-workers found that by applying thermal stress on pathogenic Leptospira serovar Lai, varying the temperature at 20, 30 and 37°C, the lipL48 was unaffected (Haake and Matsunaga, 2002). This finding suggests that 48-kDa could be damaged by UV-A radiation not by heat ...

  10. Comparison of the effects of UV-A radiation on Leptospira interrogan ...

    African Journals Online (AJOL)

    USER

    2010-05-24

    May 24, 2010 ... Full Length Research Paper. Comparison of the effects of UV-A radiation on. Leptospira interrogan serovar Bataviae, Canicola and. Pomona. Sudarat Chadsuthi1, Jirasak Wong-ekkabut1,2, Wannapong Triampo1,3,6*, Galayanee. Doungchawee4 and Darapond Triampo1,3,5,6. 1Group of Biological and ...

  11. Correction of aggregative thrombocytes activity in patients with unstable angina by THz irradiation of nitrogen oxide occurrence at in vitro conditions

    Directory of Open Access Journals (Sweden)

    Vyacheslav F. Kirichuk

    2013-11-01

    Full Text Available There had been shown a normalizing effect of THz radiation of MEAS (molecular emission and absorption spectrum of 400 GHz nitrogen oxide occurrence on aggregation parameters of thrombocytes in patients with unstable angina at in vitro conditions. 180 patients with an unstable angina had been involved in to the research.

  12. Endonuclease IV Is the Main Base Excision Repair Enzyme Involved in DNA Damage Induced by UVA Radiation and Stannous Chloride

    Directory of Open Access Journals (Sweden)

    Ellen S. Motta

    2010-01-01

    Full Text Available Stannous chloride (SnCl2 and UVA induce DNA lesions through ROS. The aim of this work was to study the toxicity induced by UVA preillumination, followed by SnCl2 treatment. E. coli BER mutants were used to identify genes which could play a role in DNA lesion repair generated by these agents. The survival assays showed (i The nfo mutant was the most sensitive to SnCl2; (ii lethal synergistic effect was observed after UVA pre-illumination, plus SnCl2 incubation, the nfo mutant being the most sensitive; (iii wild type and nfo mutants, transformed with pBW21 plasmid (nfo+ had their survival increased following treatments. The alkaline agarose gel electrophoresis assays pointed that (i UVA induced DNA breaks and fpg mutant was the most sensitive; (ii SnCl2-induced DNA strand breaks were higher than those from UVA and nfo mutant had the slowest repair kinetics; (iii UVA+SnCl2 promoted an increase in DNA breaks than SnCl2 and, again, nfo mutant displayed the slowest repair kinetics. In summary, Nfo protects E. coli cells against damage induced by SnCl2 and UVA+ SnCl2.

  13. Susceptibility to UV-A and UV-B provocation does not correlate with disease severity of polymorphic light eruption.

    Science.gov (United States)

    Janssens, Artiena Soe; Pavel, Stan; Ling, Tsui; Winhoven, Sandra Maria; Anastasopoulou, Nikoletta; Stratigos, Alexander; Antoniou, Christina; Diepgen, Thomas; de Gruijl, Frank; Rhodes, Lesley Elisabeth

    2007-05-01

    To examine whether the ease of disease provocation by UV-A and/or UV-B radiation correlates with clinical features of polymorphic light eruption (PLE), including those indicative of disease severity. Intervention study. One hundred forty-three patients with PLE. Provocation testing with broadband UV-A and UV-B lamps. Additionally, a range of clinical characteristics of the disorder, including a 5-item PLE severity score, was assessed by questionnaire. Percentage of PLE rash induction by UV-A and UV-B provocation, differences between the skin types, and correlation between the results of provocation and a range of clinical characteristics of the disorder, including a 5-item PLE severity score. Rash provocation was seen in 78.3% of patients after UV-A and in 46.7% after UV-B exposure. Neither UV-A nor UV-B provocation showed a significant association with the total 5-item severity score. The UV-B reactivity was associated with a high score on the severity item "number of months affected per year" (P = .04), whereas UV-A responsiveness showed a tendency for association with facial involvement (P = .06). The objective assessment of UV-A or UV-B susceptibility in this large group of patients showed no significant relationship with clinical disease severity.

  14. Disinfection of Spacecraft Potable Water Systems by Photocatalytic Oxidation Using UV-A Light Emitting Diodes

    Science.gov (United States)

    Birmele, Michele N.; O'Neal, Jeremy A.; Roberts, Michael S.

    2011-01-01

    Ultraviolet (UV) light has long been used in terrestrial water treatment systems for photodisinfection and the removal of organic compounds by several processes including photoadsorption, photolysis, and photocatalytic oxidation/reduction. Despite its effectiveness for water treatment, UV has not been explored for spacecraft applications because of concerns about the safety and reliability of mercury-containing UV lamps. However, recent advances in ultraviolet light emitting diodes (UV LEDs) have enabled the utilization of nanomaterials that possess the appropriate optical properties for the manufacture of LEDs capable of producing monochromatic light at germicidal wavelengths. This report describes the testing of a commercial-off-the-shelf, high power Nichia UV-A LED (250mW A365nnJ for the excitation of titanium dioxide as a point-of-use (POD) disinfection device in a potable water system. The combination of an immobilized, high surface area photocatalyst with a UV-A LED is promising for potable water system disinfection since toxic chemicals and resupply requirements are reduced. No additional consumables like chemical biocides, absorption columns, or filters are required to disinfect and/or remove potentially toxic disinfectants from the potable water prior to use. Experiments were conducted in a static test stand consisting of a polypropylene microtiter plate containing 3mm glass balls coated with titanium dioxide. Wells filled with water were exposed to ultraviolet light from an actively-cooled UV-A LED positioned above each well and inoculated with six individual challenge microorganisms recovered from the International Space Station (ISS): Burkholderia cepacia, Cupriavidus metallidurans, Methylobacterium fujisawaense, Pseudomonas aeruginosa, Sphingomonas paucimobilis and Wautersia basilensis. Exposure to the Nichia UV-A LED with photocatalytic oxidation resulted in a complete (>7-log) reduction of each challenge bacteria population in <180 minutes of contact

  15. Application of UVA-riboflavin crosslinking to enhance the mechanical properties of extracellular matrix derived hydrogels.

    Science.gov (United States)

    Ahearne, Mark; Coyle, Aron

    2016-02-01

    Hydrogels derived from extracellular matrix (ECM) have become increasing popular in recent years, particularly for use in tissue engineering. One limitation with ECM hydrogels is that they tend to have poor mechanical properties compared to native tissues they are trying to replicate. To address this problem, a UVA (ultraviolet-A) riboflavin crosslinking technique was applied to ECM hydrogels to determine if it could be used to improve their elastic modulus. Hydrogels fabricated from corneal, cardiac and liver ECM were used in this study. The mechanical properties of the hydrogels were characterized using a spherical indentation technique. The microstructure of the hydrogels and the cytotoxic effect of crosslinking on cell seeded hydrogels were also evaluated. The combination of UVA light and riboflavin solution led to a significant increase in elastic modulus from 6.8kPa to 24.7kPa, 1.4kPa to 6.9kPa and 0.9kPa to 1.6kPa for corneal, cardiac and liver ECM hydrogels respectively. The extent of this increase was dependent on a number of factors including the UVA exposure time and the initial hydrogel concentration. There were also a high percentage of viable cells within the cell seeded hydrogels with 94% of cells remaining viable after 90min exposure to UVA light. These results suggest that UVA-riboflavin crosslinking is an effective approach for improving the mechanical properties of ECM hydrogels without resulting in a significant reduction of cell viability. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Effect of altitude on solar UVR and spectral and spatial variations of UV irradiances measured inWagrain, Austria in winter

    DEFF Research Database (Denmark)

    Baczynska, Katarzyna A; Pearson, Andy J; O'Hagan, John B

    2013-01-01

    Ultraviolet radiation spectral irradiance was measured at different altitudes on horizontal and tilted planes in different azimuth directions on cloudless days in Austria, in March 2010, within the Impact of Climatic and Environmental factors on Personal Ultraviolet Radiation Exposure project...... framework. The presented results demonstrate variations of the UVB, UVA and biologically effective spectral irradiance measured on inclined and horizontal surfaces with east, west and south azimuth directions of the vertical surface and the angular position of a detector....

  17. In vitro evaluation of the morphologic changes on the root dentine irradiated by CO{sub 2} laser associated or not to calcium hydroxide application; Avaliacao in vitro das alteracoes morfologicas da superficie da dentina radicular irradiada pelo laser de CO{sub 2} associado ou nao a aplicacao de hidroxido de calcio

    Energy Technology Data Exchange (ETDEWEB)

    Romano, Ana Cristina Cury Camargo

    2003-07-01

    This in vitro study has evaluated the structural changes on the root dentine irradiated by a CO{sub 2} laser associated or not to calcium hydroxide application, from the irradiated surface analysis by means of Scanning Electronic Microscopy (SEM). The purpose of this evaluation has been the study of an alternative method for the treatment of dentine hypersensitivity. Fourteen human teeth were utilized, third molars, divided into 7 groups. Group I (control group) to which no treatment was applied; Groups II, III and IV were given an application of Ca (OH){sub 2} paste followed by C0{sub 2} laser irradiation, lasting 5 seconds each with intervals of 10 seconds between each application, with continuous emission, power of 0.5 W (Group II), 1.0 W (Group III), and 1.5 W (Group IV); Groups V, VI, and VII were given laser irradiations without the Ca (OH){sub 2} paste following the same parameters applied to groups II, III, and IV respectively. Morphologic changes suggesting to fusion and re-solidification have been observed, as well as the presence of material obstructing the whole analyzed surface on groups II, III, and IV (laser + Ca (OH){sub 2}). As for groups V, VI, and VII, it has been observed fusion, re-solidification, and cracks, and these results being statistically significant when compared the '(Ca (OH){sub 2})' groups to the laser groups. No statistically significant differences were observed regarding the different powers applied in the groups that used the same treatment. Despite this result, it can be stated that powers above 1.0 W (DP = 125,38 W/cm{sup 2}) are unfavorable due to the undesirable morphologic alterations and aesthetic compromising. (author)

  18. Biomechanical property analysis after corneal collagen cross-linking in relation to ultraviolet A irradiation time.

    Science.gov (United States)

    Lanchares, Elena; del Buey, María Angeles; Cristóbal, José Angel; Lavilla, Laura; Calvo, Begoña

    2011-08-01

    To study the biomechanical effect of riboflavin-ultraviolet A irradiation (UVA)-induced collagen cross-linking (CXL) in porcine corneas using two different exposure times of 30 and 60 min. Seventeen enucleated porcine eyes were divided into three groups: group A, six eyes without any treatment, group B, six eyes treated by UVA CXL for 30 min, and group C, five eyes treated by UVA CXL for 60 min. Riboflavin (vitamin B2) was used as a photosensitizer in both groups of treatment. Then, the stress-strain behavior of all the specimens was measured to compare the corneal biomechanical properties among the three groups. The Young's modulus E of the mean curve of each group shows the stiffness of treated and untreated tissue. The stress data necessary for stretches of 6, 8, and 12% were used to perform the statistical analysis of the values. Group B (riboflavin-UVA-CXL, 30 min, E = 46 MPa) showed a stiffer behavior than group A (control, E = 29 MPa) . Group C (60 min CXL, E = 28 MPa) showed lower stiffness than group B and a similar mechanical behavior than group A. The statistical analysis of the stress-strain curves showed significant differences in the corneal response between group B and the control at the three values of stretch considered, 6, 8, and 12% (p = 0.025, p = 0.025 and p = 0.037, respectively) and between group B and group C (p = 0.028, p = 0.028, and p = 0.028). No statistically significant difference was found between group C and control (p = 0.855, p = 0.715, and p = 0.584). The application of 30-min UVA CXL treatment with riboflavin increased stiffness of the porcine corneal tissue. A 60-min UVA-radiated tissue presents lower stiffness than the 30-min treated tissue, showing a similar biomechanical behavior than the untreated corneas. A prolongation of the UVA irradiation time may cause structural weakening of the porcine corneas.

  19. Defensive effects of fullerene-C60/liposome complex against UVA-induced intracellular reactive oxygen species generation and cell death in human skin keratinocytes HaCaT, associated with intracellular uptake and extracellular excretion of fullerene-C60.

    Science.gov (United States)

    Kato, Shinya; Kikuchi, Risa; Aoshima, Hisae; Saitoh, Yasukazu; Miwa, Nobuhiko

    2010-02-12

    The UVA-irradiation of 10 J/cm(2) on HaCaT keratinocytes increased 59.1% of the intracellular reactive oxygen species (ROS) by NBT assay and the cell viability decreased to 31.5% by WST-1 assay, comparing to the non-irradiated control. In the presence of fullerene-C60 (C60) incorporated in phospholipid membrane vehicle (LiposomeFullerene: Lpsm-Flln) of 250-500 ppm, they were restored to -9.1% to +2.3% of the ROS and 83.0-84.8% of the cell viability, but scarcely restored by the liposome without C60 (Lpsm). In HaCaT cells administered with Lpsm-Flln (150 ppm), C60 was ingested at the intracellular concentrations of 1.4-21.9 ppm for 4-24 h, and, intracellular C60 was excreted by 80% at 4h after rinsing-out, and decreased to 2-10% after 24-48 h. C60 was predominantly distributed around the outside of nuclear membrane without deterioration of intact cell morphology according to fluorescent immunostain. Thus Lpsm-Flln is found to be an effective antioxidant that could preserve HaCaT keratinocytes against UVA-induced cellular injury. Lpsm-Flln has a potential to serve as a cosmetic material for skin protection against UVA. Copyright 2009 Elsevier B.V. All rights reserved.

  20. In vitro antioxidant and in vivo photoprotective effects of an association of bioflavonoids with liposoluble vitamins.

    Science.gov (United States)

    Maia Campos, Patrícia M B G; Gianeti, Mirela D; Kanashiro, Alexandre; Lucisano-Valim, Yara M; Gaspar, Lorena R

    2006-01-01

    A new tendency in cosmetic formulations is the association of botanical extracts and vitamins to improve skin conditions by synergic effects. The objective of this study was to determine the antioxidant activity of associated bioflavonoids, retinyl palmitate (RP), tocopheryl acetate (TA) and ascorbyl tetraisopalmitate (ATIP), as well as their photoprotective effects in preventing increased erythema, transepidermal water loss (TEWL) and sunburn cell formation in hairless mouse skin. The antioxidant activity of solutions containing the association or each substance separately was evaluated in vitro by a chemiluminescence assay. The photoprotective effect was evaluated by means of in vivo tests. Dorsal skin of hairless mice was treated daily by topical applications for 5 days with formulations containing or not containing (vehicle) the flavonoid-vitamins association (5%). The skin was irradiated (UVA/B) 15 minutes after the last application. The results showed that bioflavonoids had in vitro antioxidant properties and also that when they were associated with vitamins their antioxidant activity was more pronounced. On the other hand, erythema and UV damage to the permeability barrier function (TEWL) was not significantly reduced by previous treatment with the flavonoid-vitamin-association formulations, when compared to the irradiated vehicle-treated area. However, the treatment protected the skin from UV damage because it reduced the number of sunburn cells, when compared to the vehicle-treated area. Finally, the association of vitamins and bioflavonoids added to a dermocosmetic formulation showed a relevant biological activity in terms of photoprotection, because the association of bioflavonoids and vitamins acted by different mechanisms, such as antioxidation and absorption of UV radiation, which suggests its use in antiaging and photoprotective products.

  1. Effectiveness of gamma ray irradiation and ethyl methane ...

    African Journals Online (AJOL)

    The experiment was conducted to study the effect of gamma-ray irradiation on the high concentration thidiazuron (TDZ) produced buds. In vitro buds were irradiated with different gamma-ray doses. Akihime cultivar ('Akihime') was irradiated with the doses of 0, 30, 80, 130, 180, and 230 Gy while 'DNKW001 accession' ...

  2. Requirements of blue, UV-A, and UV-B light for normal growth of higher plants, as assessed by actions spectra for growth and related phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, T. [Kobe Women`s Univ., Higashisuma (Japan)

    1994-12-31

    It is very important for experimental purposes, as well as for the practical use of plants when not enough sunlight is available. To grow green higher plants in their normal forms under artificial lighting constructing efficient and economically reasonable lighting systems is not an easy task. One possible approach would be to simulate sunlight in intensity and the radiation spectrum, but its high construction and running costs are not likely to allow its use in practice. Sunlight may be excessive in irradiance in some or all portions of the spectrum. Reducing irradiance and removing unnecessary wavebands might lead to an economically feasible light source. However, removing or reducing a particular waveband from sunlight for testing is not easy. Another approach might be to find the wavebands required for respective aspects of plant growth and to combine them in a proper ratio and intensity. The latter approach seems more practical and economical, and the aim of this Workshop lies in advancing this approach. I summarize our present knowledge on the waveband requirements of higher plants for the regions of blue, UV-A and UV-B.

  3. Irradiation subassembly

    Science.gov (United States)

    Seim, O.S.; Filewicz, E.C.; Hutter, E.

    1973-10-23

    An irradiation subassembly for use in a nuclear reactor is described which includes a bundle of slender elongated irradiation -capsules or fuel elements enclosed by a coolant tube and having yieldable retaining liner between the irradiation capsules and the coolant tube. For a hexagonal bundle surrounded by a hexagonal tube the yieldable retaining liner may consist either of six segments corresponding to the six sides of the tube or three angular segments each corresponding in two adjacent sides of the tube. The sides of adjacent segments abut and are so cut that metal-tometal contact is retained when the volume enclosed by the retaining liner is varied and Springs are provided for urging the segments toward the center of the tube to hold the capsules in a closely packed configuration. (Official Gazette)

  4. Direct effects of visible and UVA light on pigment migration in erythrophores of Nile tilapia.

    Science.gov (United States)

    Sato, Masako; Ishikura, Ryo; Oshima, Noriko

    2004-10-01

    Erythrophores derived from Nile tilapia (Oreochromis niloticus) are sensitive to visible light of defined wavelengths in primary culture in the same manner as erythrophores in the skin. Cultured erythrophores aggregate their pigment in response to light with peak wavelengths near 400 or 600 nm, while dispersion is caused by light near 500 nm. In this study, we report that ultraviolet A (UVA) with a peak wavelength near 365 nm also induces pigment aggregation in erythrophores in the skin and in primary culture. The responses of erythrophores in the skin or in culture depend on the light intensity, although the photo-sensitivity differs among individual cells. From the results, we conclude that the action of visible light and UVA light on tilapia erythrophores is direct, and that multiple types of visual pigments may coexist in individual erythrophores.

  5. The global response of Nostoc punctiforme ATCC 29133 to UVA stress, assessed in a temporal DNA microarray study.

    Science.gov (United States)

    Soule, Tanya; Gao, Qunjie; Stout, Valerie; Garcia-Pichel, Ferran

    2013-01-01

    Cyanobacteria in nature are exposed not only to the visible spectrum of sunlight but also to its harmful ultraviolet components (UVA and UVB). We used Nostoc punctiforme ATCC 29133 as a model to study the UVA response by analyzing global gene expression patterns using genomic microarrays. UVA exposure resulted in the statistically detectable differential expression of 573 genes of the 6903 that were probed, compared with that of the control cultures. Of those genes, 473 were up-regulated, while only 100 were down-regulated. Many of the down-regulated genes were involved in photosynthetic pigment biosynthesis, indicating a significant shift in this metabolism. As expected, we detected the up-regulation of genes encoding antioxidant enzymes and the sunscreen, scytonemin. However, a majority of the up-regulated genes, 47%, were unassignable bioinformatically to known functional categories, suggesting that the UVA stress response is not well understood. Interestingly, the most dramatic up-regulation involved several contiguous genes of unassigned metabolism on plasmid A. This is the first global UVA stress response analysis of any phototrophic microorganism and the differential expression of 8% of the genes of the Nostoc genome indicates that adaptation to UVA in Nostoc has been an evolutionary force of significance. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  6. Assessment of DNA double-strand breaks induced by intravascular iodinated contrast media following in vitro irradiation and in vivo, during paediatric cardiac catheterization.

    Science.gov (United States)

    Gould, Richard; McFadden, Sonyia L; Horn, Simon; Prise, Kevin M; Doyle, Philip; Hughes, Ciara M

    2016-01-01

    Paediatric cardiac catheterizations may result in the administration of substantial amounts of iodinated contrast media and ionizing radiation. The aim of this work was to investigate the effect of iodinated contrast media in combination with in vitro and in vivo X-ray radiation on lymphocyte DNA. Six concentrations of iodine (15, 17.5, 30, 35, 45, and 52.5 mg of iodine per mL blood) represented volumes of iodinated contrast media used in the clinical setting. Blood obtained from healthy volunteers was mixed with iodinated contrast media and exposed to radiation doses commonly used in paediatric cardiac catheterizations (0 mGy, 70 mGy, 140 mGy, 250 mGy and 450 mGy). Control samples contained no iodine. For in vivo experimentation, pre and post blood samples were collected from children undergoing cardiac catheterization, receiving iodine concentrations of up to 51 mg of iodine per mL blood and radiation doses of up to 400 mGy. Fluorescence microscopy was performed to assess γH2AX-foci induction, which corresponded to the number of DNA double-strand breaks. The presence of iodine in vitro resulted in significant increases of DNA double-strand breaks beyond that induced by radiation for ≥ 17.5 mg/mL iodine to blood. The in vivo effects of contrast media on children undergoing cardiac catheterization resulted in a 19% increase in DNA double-strand breaks in children receiving an average concentration of 19 mg/mL iodine to blood. A larger investigation is required to provide further information of the potential benefit of lowering the amount of iodinated contrast media received during X-ray radiation investigations. Copyright © 2015 John Wiley & Sons, Ltd.

  7. Fullerene-C60 derivatives prevent UV-irradiation/ TiO2-induced cytotoxicity on keratinocytes and 3D-skin tissues through antioxidant actions.

    Science.gov (United States)

    Kato, Shinya; Aoshima, Hisae; Saitoh, Yasukazu; Miwa, Nobuhiko

    2014-05-01

    Microcorpuscular titanium dioxide (TiO2), a useful sunscreen agent, photocatalyzes generation of reactive oxygen species (ROS). We assessed protective effects of fullerene-C60 derivatives or microcolloidal platinum (Pt) against ultraviolet ray (UV)-irradiation in the presence of TiO2 in vitro. UV-irradiation (8 J/cm2, mixed UVA and UVB) in the presence of 15 ppm TiO2 on HaCaT keratinocytes decreased cell viability as quantified by WST-1 assay, and increased both intracellular ROS and cell-membrane-lipid peroxidation, as quantified by nitroblue-tetrazolium (NBT) assay and diphenyl-1-pyrenylphosphine (DPPP) assay, respectively, whereas all of three phototoxicity-related symptoms were appreciably repressed almost to UV-unirradiational levels by pretreatment with polyvinylpyrrolidone-entrapped fullerene-C60 (C60/PVP) or fullerene-C60 dissolved in squalane (C60/Sqn) in a dose-dependent manner of C60, but scarcely by PVP alone or Sqn alone. In contrast, Pt repressed intracellular ROS generation, but did not prevent either peroxidation of cell-membrane-lipid or cell mortality. Then in the epidermis of 3-dimensional human skin tissue model, UV-irradiation in the presence of TiO2 extensively induced two symptoms such as ROS-generation around perinuclear regions and membrane-lipid peroxidation, both of which were repressed by C60/PVP or C60/Sqn, whereas Pt did not prevent membrane-lipid peroxidation adequately. Thus the advantageous application of the lipophilic antioxidant fullerene-C60 which effectively protects cell membrane against peroxidation. In conclusion, fullerene-C60 can be expected to serve as an antioxidant for scavenging of TiO2-photocatalyzed ROS in the skin surface, and therefore provide a functional improvement of TiO2-containing sunscreens.

  8. Effect of vitamin B1 and mixtures of B1 with other vitamins on cytostatic efficiency of sanazole under irradiation. A study in vitro

    Science.gov (United States)

    Heinrich, Edith; Getoff, Nikola

    2003-06-01

    Experiments in vitro, using bacteria Escherichia coli (AB 1157) as a biological model, showed that the cytostatic efficiency of sanazole (AK-2123, a nitrotriazole-type radiosensitizer) in radiation treatment can be strongly influenced by the presence of various vitamins. In airfree media the sanazole action is increased by a factor of 2.5 in the presence of vitamin (vit.) B1, vit. C E-acetate and β-carotene, whereas vit. B1 used individually possesses a 2.7-times higher cytostatic activity than sanazole itself. In media containing air the highest increase of sanazole action is observed in the presence of vit. B1 and C, whereas the individual use of vit. B1 shows a radiation protection effect. In media saturated with N 2O the addition of the vit. B1 and C causes a 1.8-times larger sanazole activity, but the application of vit. B1 alone brings about a very high radiation protection. From studies of vit. B1-radiolysis it can be concluded that OH radicals are the major primary transients leading to substrate degradation. The results are of interest for the radiation therapy of cancer.

  9. An in-vitro evaluation of the effect of 980 nm diode laser irradiation on intra-canal dentin surface and dentinal tubule openings after biomechanical preparation: Scanning electron microscopic study

    Science.gov (United States)

    Jhingan, Pulkit; Sandhu, Meera; Jindal, Garima; Goel, Deepti; Sachdev, Vinod

    2015-01-01

    Context: Very recently, diode laser has been used for disinfecting the root canals in endodontic treatment and increasing its success rate and longevity utilizing the thermal effect of laser on surrounding tissues. Aims: The aim of this study is to evaluate the effect of 980 nm laser irradiation on intra-canal dentin surface – scanning electron microscopic (SEM) - in-vitro study. Methods: A total of 40 single-rooted freshly extracted permanent teeth were collected. Teeth were sectioned at the cemento-enamel junction using diamond disc. Root canals of all samples were prepared using hand ProTaper, which were randomly assigned into two groups (n = 20 each). Group 1: Receiving no treatment after biomechanical preparation; Group 2: 980 nm diode laser-treated root canals. Teeth were prepared for SEM analysis to check the size of intra-canal dentinal tubule openings. Statistical Analysis Used: Data were analyzed using SPSS V.16 software and compared using Levene's and independent t-test. Results: On statistical analysis, width of intracanal dentinal tubule openings in Group 1 (control) was significantly higher than those observed in Group 2 (diode laser-treated) (P diode laser on intra-radicular dentin resulted in ultrastructural alterations resulting in melting of dentin. PMID:26097338

  10. Mutation spectrum produced on PBR322 by 8-Methoxypsoralen plus UV-A light. Localizacion puntual de mutaciones producidas en PBR322 por tratamiento con 8-metoxipsoraleno mas luz ultravioleta-A

    Energy Technology Data Exchange (ETDEWEB)

    Bauluz, C.; Vidania, R.

    1990-01-01

    The mutagenic effect of 8-MOP+UVA (PUVA treatment) on pBR322 has been analysed by determining the frequency of mutation in the tet gene and identifying the type and position of the mutations produced inside a 276 pb-fragment (Bam-H1-SalI) of the same gene. pBR322 DNA was irradiated with UVA light in the presence of increasing concentrations of 8-Methoxypsoralen (8-MOP). The number of psoralen adducts formed in pBR322 upon that treatment ranged from 0 to 10.7 adducts per plasmid molecule. Modified DNA samples were used to transform several strains of E. Coli (differing in their repair capacities), both in constitutive conditions and after sos pre-induction by 254 nm-irradiation of cells. Mutation frequencies in the tet gene showed to increase in the wild type and uvrA strains along with the number of psoralen adduts per plasmid molecule; higher mutation frequencies were found in cells that had been previously irradiated to induce the SOS expression. Mutant plasmids were isolated from ApRTcS colonies and sequenced by the method of Maxam and Gilbert. Mutations appeared to be unique in most of the cases and were always punctual, i.e. affecting only to one base pair. The relative positions of the mutations showed a high frequency of coincidence among the sequenced fragments, indicating the existence of several DNA regions with high probability to mutated ([sup h]ot spots[sup )]. (author)

  11. Mutation spectrum produced on PBR322 by 8-Methoxypsoralen plus UV-A light; Localizacion puntual de mutaciones producidas en PBR322 por tratamiento con 8-metoxipsoraleno mas luz ultravioleta-A

    Energy Technology Data Exchange (ETDEWEB)

    Bauluz, C.; Vidania, R.

    1990-12-31

    The mutagenic effect of 8-MOP+UVA (PUVA treatment) on pBR322 has been analysed by determining the frequency of mutation in the tet gene and identifying the type and position of the mutations produced inside a 276 pb-fragment (Bam-H1-SalI) of the same gene. pBR322 DNA was irradiated with UVA light in the presence of increasing concentrations of 8-Methoxypsoralen (8-MOP). The number of psoralen adducts formed in pBR322 upon that treatment ranged from 0 to 10.7 adducts per plasmid molecule. Modified DNA samples were used to transform several strains of E. Coli (differing in their repair capacities), both in constitutive conditions and after sos pre-induction by 254 nm-irradiation of cells. Mutation frequencies in the tet gene showed to increase in the wild type and uvrA strains along with the number of psoralen adduts per plasmid molecule; higher mutation frequencies were found in cells that had been previously irradiated to induce the SOS expression. Mutant plasmids were isolated from ApRTcS colonies and sequenced by the method of Maxam and Gilbert. Mutations appeared to be unique in most of the cases and were always punctual, i.e. affecting only to one base pair. The relative positions of the mutations showed a high frequency of coincidence among the sequenced fragments, indicating the existence of several DNA regions with high probability to mutated ({sup h}ot spots{sup )}. (author)

  12. Dermal toxicity of 8-methoxypsoralen administered (by gavage) to hairless mice irradiated with long-wave ultraviolet light

    Energy Technology Data Exchange (ETDEWEB)

    Langner, A.; Wolska, H.; Marzulli, F.N.; Jablonska, S.; Jarzabek-Chorzelska, M.; Glinski, W.; Pawinska, M.

    1977-11-01

    Hairless mice were administered various amounts of 8-methoxypsoralen (8-MOP) by gavage, followed by irradiation with ultraviolet light (UVA) two or more times per week for periods ranging from 1 to 12 months. The minimum phototoxic dose was 20 mg/kg body weight by this route of administration and potential for serious organ toxicity in long-term exposures was investigated. No histologic features of cutaneous malignancy were encountered under test conditions which produced prolonged phototoxicity, deep ulceration, cicatrization, and other deformities. Repeated daily gavaged doses of 20 mg psoralen/Kg body weight in conjunction with twice weekly irradiation for 10 min with UVA elicited an erythematous phototoxic reaction, but did not give rise to subsequent skin lesions. 8-MOP in repeated daily gavage doses of 30 mg and 40 mg/kg body weight combined with twice weekly UVA irradiation for 10 min caused severe burning with subsequent scarring, but did not induce malignant tumors in experiments lasting 8 months. No organ toxicity was seen except for toxic liver changes when severe cutaneous burn and pronounced ulcerations were produced. Limited immunologic studies disclosed no abnormalities in this system.

  13. Photopheresis with UV-A light and 8-methoxypsoralen leads to cell death and to release of blebs with anti-inflammatory phenotype in activated and non-activated lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Stadler, K. [Department for Internal Medicine 3, University Hospital Erlangen (Germany); Frey, B. [Department of Radiation Oncology, University Hospital Erlangen, Universitaetsstr. 27, 91054 Erlangen (Germany); Munoz, L.E.; Finzel, S.; Rech, J. [Department for Internal Medicine 3, University Hospital Erlangen (Germany); Fietkau, R. [Department of Radiation Oncology, University Hospital Erlangen, Universitaetsstr. 27, 91054 Erlangen (Germany); Herrmann, M. [Department for Internal Medicine 3, University Hospital Erlangen (Germany); Hueber, A. [Centre for Rheumatic Diseases, University of Glasgow (United Kingdom); Gaipl, U.S., E-mail: udo.gaipl@uk-erlangen.de [Department of Radiation Oncology, University Hospital Erlangen, Universitaetsstr. 27, 91054 Erlangen (Germany)

    2009-08-14

    Background: Extracorporeal photopheresis is a therapy for treatment of autoimmune diseases, cutaneous T-cell lymphoma, organ graft rejection as well as graft-versus-host diseases. The exact mechanism how the combination of 8-methoxypsoralen plus UV-A irradiation (PUVA) acts is still unclear. We investigated the cell death of activated and non-activated lymphocytes after PUVA treatment as well as the rate of released blebs and their antigen composition. Results: In presence of 8-MOP, UV-A light highly significantly increased the cell death of activated lymphocytes. The same was observed to a lesser extent in non-activated cells. Blebs derived from activated lymphocytes after PUVA treatment showed the highest surface exposition of phosphatidylserine. These blebs also displayed a high exposure of the antigens CD5 and CD8 as well as a low exposure of CD28 and CD86. Conclusion: PUVA treatment exerts anti-inflammatory effects by inducing apoptosis and apoptotic cell-derived blebs with immune suppressive surface composition.

  14. Use of potassium bicarbonate (Armicarb) on the control of powdery mildew (Sphaerotheca mors-uvae) of gooseberry (Ribes uva-crispa).

    Science.gov (United States)

    Wenneker, M; Kanne, J

    2010-01-01

    Powdery mildew (Sphaerotheca mors-uvae) severely infects young shoots, stems and fruits of gooseberry (Ribes uva-crispa). Environmental friendly and biological control measures are being sought throughout the world. Especially in organic gooseberry growing effective control measures are needed, because powdery mildew infections may result in a total loss of the crop. In organic currant growing the number of adequate control methods is very limited. Sulphur as a fungicide against powdery mildew in e.g. gooseberry or table grape growing is not recommendable due to possible bleaching of berries and scorching of tender shoots. Various bicarbonate salts are suggested as a good option to control powdery mildew. In a field trial the effect of potassium bicarbonate (Armicarb) on the on the control of powdery mildew of gooseberry was evaluated. Four treatments; i.e. two preventive strategies and two curative strategies, were applied. PLants were sprayed until runoff. The percent of infected fruits and disease severity were assessed. In the unsprayed control plots very high disease incidences were observed; on average more than 90% of the berries were infected with powdery mildew. The weekly (preventive) spray applications with potassium carbonate reduced the disease incidences on fruits significantly. On average approximately 10% of the fruits were affected by powdery mildew. However, the number of spray applications was high. In conclusion, our results indicate that applications of potassium bicarbonate (as Armicarb) are effective in reducing the incidence and severity of American powdery mildew in gooseberry. Early spray applications are necessary to protect berries against powdery mildew infections. Future research will focus on reducing the number of applications, e.g. warning models based on powdery mildew of rose (Sphaerotheca pannosa).

  15. In vitro bond strength of an epoxy resin-based root canal sealer to root dentin irradiated with high-power lasers and adhesive interface analyses.

    Science.gov (United States)

    Araujo, Vanessa Lessa C; Cruvinel, Pedro Basto; Palma-Dibb, Regina Guenka; Gariba-Silva, Ricardo

    2018-02-01

    The aim of this study was to evaluate in vitro the influence of high-power lasers (Nd:YAG and diode 980 nm) associated with mineral coal as fotopotencializer on bond strength of an epoxy resin-based root canal sealer to root dentin, using the pushout test, and on the dentin/filling material interface, using confocal laser microscopy. For this purposes, 50 canines were instrumented with Mtwo rotary system up to #50.04 instrument and randomly assigned to five groups (n = 10): group I-control EDTAC; group II-EDTAC and Nd:YAG laser; group III-EDTAC and diode laser 980 nm; group IV-EDTAC, Nd:YAG laser and mineral coal 5 g/100 mL; and group V-EDTAC, diode laser 980 nm and mineral coal 5 g/100 mL. All data were analyzed by ANOVA (at 5% significance level) following the Kruskal-Wallis, Dunn and Tukey tests. The group I increased more bond strength of the sealer to root dentin that treated with only EDTAC 17% (17.21 ± 21.75 MPa), similar to the group II (12.21 ± 18.20 MPa) and group IV (14.92 ± 28.06 MPa), both treated with Nd:YAG laser, with the exception of group IV, which was added to mineral coal. The group V (8.75 ± 13.42 MPa) had similar results to the groups II and IV, but the same similarity were found when compared with group III (7.11 + 11.28 MPa), with lower results. Regarding the root thirds, the apical third (23.27 ± 29.21 MPa) presented a statistically higher value on bond strength than the cervical third (5.92 ± 5.33 MPa) and middle third (6.93 ± 7, 11 MPa) (p > 0.05). Group II (86.27 μm) showed the highest tags penetration values, with a statistically difference to the group III (51.57 μm), IV (36.77 μm) and V (32.37 μm) (p  0.05). Group IV had the lowest values and was statistically similarity to groups III and V (p > 0.05). It was concluded that the treatment with Nd:YAG laser provides better results than the diode 980 nm laser, except when was added mineral coal. The control and diode 980 nm laser

  16. Mycorrhiza of the host-specific Lactarius deterrimus on the roots of Picea abies and Arctostaphylos uva-ursi.

    Science.gov (United States)

    Mühlmann, O; Göbl, F

    2006-06-01

    The ectomycorrhizal basidiomycete species Lactarius deterrimus Gröger is considered to be a strictly host-specific mycobiont of Picea abies (L.) Karst. However, we identified arbutoid mycorrhiza formed by this fungus on the roots of Arctostaphylos uva-ursi (L.) Spreng. in a mixed stand at the alpine timberline; typical ectomycorrhiza of P. abies were found in close relation. A. uva-ursi is known as an extremely unspecific phytobiont. The mycorrhizae of both associations are described and compared morphologically. The mycorrhiza formed by L. deterrimus on both A. uva-ursi and P. abies show typical ectomycorrhizal features such as a hyphal mantle and a Hartig net. The main difference between the mycorrhizal symbioses with the different phytobionts is the occurrence of intracellular hyphae in the epidermal cells of A. uva-ursi. This emphasizes the importance of the plant partner for mycorrhizal anatomy. This is the first report of a previously considered host-specific ectomycorrhizal fungus in association with A. uva-ursi under natural conditions. The advantages of this loose specificity between the fungus and plant species is discussed.

  17. Effects of urban pollution on UV spectral irradiances

    Directory of Open Access Journals (Sweden)

    R. L. McKenzie

    2008-09-01

    Full Text Available Spectral measurements of UV irradiances at Tokyo are compared with corresponding measurements at a pristine site (Lauder New Zealand to identify the causes of the reductions in urban UV irradiances, and to quantify their effects. Tropospheric extinctions in Tokyo were found to be up to ~40% greater than at Lauder. Most of these differences can be explained by differences in cloud and aerosols, but ozone differences are also important in the summer. Examining spectral signatures of tropospheric transmission of both sites shows that reductions due to mean NO2 and SO2 amounts are generally small. However, at times the amount of NO2 can be 10 times higher than the mean amount, and on these days it can decrease the UVA irradiance up to 40%. If SO2 shows comparable day to day variability, it would contribute to significant reductions in UVB irradiances. The results indicate that at Tokyo, interactions between the larger burden of tropospheric ozone and aerosols also have a significant effect. These results have important implications for our ability to accurately retrieve surface UV irradiances at polluted sites from satellites that use backscattered UV. Supplementary data characterising these boundary layer effects are probably needed.

  18. Assessment of cumulative exposure to UVA through study of asymmetric facial skin damage

    Directory of Open Access Journals (Sweden)

    Sophie Mac-Mary1

    2010-09-01

    Full Text Available Sophie Mac-Mary1, Jean-Marie Sainthillier1, Adeline Jeudy3, Christelle Sladen2, Cara Williams2, Mike Bell2, Philippe Humbert31Skinexigence SAS, Saint-Jacques University Hospital, Besançon, France; 2The Boots Company, Nottingham, United Kingdom; 3Research and Studies Center on the Integument, Department of Dermatology, Saint-Jacques University Hospital, University of Franche-Comté, Besançon, FranceBackground: Published studies assessing whether asymmetric facial ultraviolet light exposure leads to underlying differences in skin physiology and morphology are only observational. The aim of this study was to assess the visual impact on the skin of repeated ultraviolet-A (UVA exposure through a window.Methods: Eight women and two men presenting with asymmetric signs of photoaging due to overexposure of one side of their face to the sun through a window over a long period of time were enrolled in the study. Split-face biometrologic assessments were performed (clinical scoring, hydration with Corneometer®, mechanical properties with a Cutometer®, transepidermal water loss with AquaFlux®, skin relief with fringe projection, photography, stripping, and then lipid peroxidation analyses.Results: Significant differences were observed in clinical scores for wrinkles, skin roughness assessed by fringe projection on the cheek, and skin heterogeneity assessed with spectrocolorimetry on the cheekbone. Other differences were observed for skin hydration, as well as skin laxity, which tended towards significance.Discussion: This study suggests the potential benefit of daily UVA protection during nondeliberate exposure indoors as well as outside.Keywords: UVA, asymmetry, photodamage, face

  19. Extração de antocianina de casca de uva Isabel

    OpenAIRE

    Mezaroba, Maria Elizabeth de Paula Cançado

    2001-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Química Este estudo objetivou avaliar a concentração de antocianina (corantes naturais) presentes no suco extraído da casca de uva da variedade Isabel . No processo de extração de antocianinas foram utilizados água e condensado vegetal com dióxido de enxofre a diferentes concentrações (1200, 1500, 2000ppm) com e sem enzima e etanol acidificado a 1% com e sem enzima. ...

  20. The selects of bearberry (Arctostaphylos uva-ursi (l. spreng. from natural populations in Poland

    Directory of Open Access Journals (Sweden)

    Hanna Malinowska

    2014-01-01

    Full Text Available Five plants of bearberry selected from natural stands in Poland and one from a Botanical Garden were propagated by cuttings. The clonal plants were first kept under observation for two years planted on different substrates in containers and were afterwards field cultivated for three subsequent years. The existence of a significant differentiation within these Arctostaphylos uva-ursi clones was proved. Two selects of good ornamental features as well as with high concentration of medicinal substance - arbutin were chosen. Plants started fruiting in the fourth year of growth and the area covered by a single plant exceeded 2 m2 after five years of cultivation.

  1. Curtición vegetal con extracto de semilla de uva

    OpenAIRE

    Ramon Arcal, Salvador; Bacardit Dalmases, Anna; Font Vallès, Joaquim; Ollé Otero, Lluís

    2012-01-01

    El objetivo de este trabajo es estudiar la viabilidad de usar el extracto de semilla de uva procedente de subproductos de la industria vinícola, como fuente sostenible y renovable de taninos para curtir pieles vacunas al vegetal, frente a los extractos vegetales convencionales de quebracho, mimosa, castaño, gambier, o tara que provienen de arboles cultivados en zonas geográficas concretas. La substitución parcial en el proceso industrial de las tenerías de alguno de los extractos ...

  2. Manejo de residuos solidos en un evento turistico: Fiesta Nacional de la Uva (RS - Brasil)

    OpenAIRE

    Pereira, Gisele Silva; Conto,Suzana Maria De

    2008-01-01

    este artículo plantea al manejo de residuos solidos como objecto de estudio en eventos turisticos. El trabajo de campo se realisó con tecnicas de observación directa y entrevistas. Éstas ultimas fueron realizadas al presidente, los dos vice-presidentes y los directores de las 15 comisiones organizadoras de la Fiesta Nacional de la Uva 2006. Los resultados muestram la importancia de desarrollar programas de educaciín ambiental para los colaboradores de la fiesta y de considerar el control de l...

  3. Divergência fenotípica entre acessos de uvas de mesa no Semi-Árido brasileiro

    OpenAIRE

    Borges,Rita Mércia Estigarribia; Gonçalves,Nadja Pollyanna da Silva; Gomes,Ana Patrícia de Oliveira; Alves,Elaini Oliveira dos Santos

    2008-01-01

    O objetivo deste trabalho foi avaliar a divergência fenotípica em uvas da Coleção da Embrapa Semi-Árido, com base em oito variáveis morfoagronômicas avaliadas nos anos 2005 e 2006. Nas uvas com sementes, a análise por componentes principais identificou oito grupos contrastantes. As variáveis mais relevantes, quanto à divergência genética, foram peso e comprimento de bagas. Em uvas sem sementes, formou-se apenas um grupo, e as variáveis mais relevantes foram peso de bagas e produção. A distânc...

  4. Six-day selenium supplementation led to either UVA-photoprotection or toxic effects in human fibroblasts depending on the chemical form and dose of Se.

    Science.gov (United States)

    Hazane-Puch, Florence; Champelovier, Pierre; Arnaud, Josiane; Trocmé, Candice; Garrel, Catherine; Faure, Patrice; Laporte, François

    2014-09-01

    Selenium (Se) is an essential trace element with a narrow safety zone and unclear effects on skin photoageing. The aim of this work was to investigate the photoageing properties of sodium selenite or selenomethionine (SeMet) after a long term (6 days) Se supplementation in normal human skin fibroblasts (NHSF) subjected to ultraviolet-A (UVA) irradiation inducing 30% cell death. The uptake, toxicity and antioxidant effects of sodium selenite and SeMet were compared to better understand their photoageing properties. SeMet uptake was better than sodium selenite and their uptake by fibroblasts was not via an actively transport process. Sodium selenite induced a higher toxicity than SeMet. At 5 μM, sodium selenite inhibited cell proliferation associated with a blockage in the G2 phase and induced DNA fragmentation leading to caspase-3-dependent apoptosis cell death. At low doses (selenium forms. SeMet may be a potential agent for the prevention and treatment of skin photoageing.

  5. EVOLUÇÃO DA COR DURANTE A MATURAÇÃO DAS UVAS TINTAS

    Directory of Open Access Journals (Sweden)

    Gilberto Massashi Ide

    1993-08-01

    Full Text Available Foram feitos estudos de tonalidade e intensidade de cor na película e na polpa durante o desenvolvimento e a maturação da uva das cultivares Cabernet Sauvignon, Cabernet Franc, Merlot, Pinot Noir (Vitis vinifera e Isabel (Vitis labrusca nas safras de 1990 e 1991. A tonalidade na película diminuiu acentuadamente no início do desenvolvimento das bagas estabilizando-se após a "veraison". As boas condições climáticas (baixa precipitação pluviométrica e umidade, alta insolação da safra de 1991 tiveram pouca influência sobre a tonalidade. A intensidade de cor na película aumentou durante a maturação da uva e as condições climáticas de 1991 propiciaram maior intensidade nas cultivares Cabernet Sauvignon, Cabernet Franc e Merlot pouco influindo, no entanto, nas cultivares Pinot Noir e Isabel. Na polpa houve estabilidade da intensidade de cor, porém, a tonalidade apresentou-se variável com tendência a estabilizar-se durante a maturação.

  6. Suco de uva enriquecido com soro: elaboração e aceitabilidade sensorial

    Directory of Open Access Journals (Sweden)

    Simone Vilela Talma

    2010-04-01

    Full Text Available Estudos têm sido realizados em diversos países visando oferecer ao mercado novas formas de utilização do soro de leite. O objetivo deste trabalho foi desenvolver suco de uva enriquecido com soro lácteo e avaliar a aceitação sensorial utilizando a escala hedônica facial e a técnica Mapa de Preferência. As diferentes formulações foram avaliadas por 111 crianças com idade entre 7 e 11 anos, no período de setembro a novembro de 2009, em uma escola pública do município de Rio Pomba, MG. Para o preparo da bebida foram adicionados 250 mL de suco de uva concentrado em 1750 mL da mistura de água e soro nas proporções de 40%, 60%, 80% e 100% de soro e 7% de açúcar. As amostras que continham 40% e 60% de soro na mistura de água e soro foram classificadas pelas crianças entre os termos hedônicos "gostei extremamente" e "gostei moderadamente", respectivamente, indicando a boa aceitação pela maioria dos consumidores. Entretanto, do total de provadores, 44 classificaram a amostra contendo 100% de soro na mistura entre os termos hedônicos "desgostei moderadamente" e "desgostei extremamente" indicando rejeição.

  7. Novas metodologias analíticas para avaliação da eficácia fotoprotetora (in vitro – revisão

    Directory of Open Access Journals (Sweden)

    MARIA VALéRIA ROBLES VELASCO

    2011-06-01

    Full Text Available Atualmente, são utilizadas técnicas in vitro e in vivo para a avaliação do Fator de Proteção Solar (FPS e do Fator de Proteção de UVA (FPA. O presente trabalho propõe a revisão das técnicas para as avaliações desses fatores in vitro preconizadas por FDA (Food and Drug Administration Agency e COLIPA (European Cosmetic, Toiletry and Perfumery Association. O enfoque maior foi direcionado à análise espectrofotométrica de soluções diluídas e à espectrofotometria de reflectância com esfera integrada. Palavras-chave: Espectrofotometria. Fotoproteção. UVA. UVB. Revisão. ABSTRACT New analytical methods for photoprotection effectiveness testing (in vitro – a review Currently, both in vitro and in vivo techniques are used to measure Sun Protection Factor (SPF and UVA Protection Factor (APF. This paper reviews the in vitro techniques to test these factors, recommended by the FDA (USA Food and Drug Administration and COLIPA (European Cosmetic, Toiletry and Perfumery Association. The main focus is on the spectrophotometric analysis of dilute solutions and the use of reflectance spectrophotometry with an integrating sphere. Keywords: Spectrophotometry. Photoprotection. UVA. UVB. Review.

  8. Phytosanitary Irradiation

    Directory of Open Access Journals (Sweden)

    Guy J. Hallman

    2016-01-01

    Full Text Available Phytosanitary treatments disinfest traded commodities of potential quarantine pests. Phytosanitary irradiation (PI treatments use ionizing radiation to accomplish this, and, since their international commercial debut in 2004, the use of this technology has increased by ~10% annually. Generic PI treatments (one dose is used for a group of pests and/or commodities, although not all have been tested for efficacy are used in virtually all commercial PI treatments, and new generic PI doses are proposed, such as 300 Gy, for all insects except pupae and adult Lepidoptera (moths. Fresh fruits and vegetables tolerate PI better than any other broadly used treatment. Advances that would help facilitate the use of PI include streamlining the approval process, making the technology more accessible to potential users, lowering doses and broadening their coverage, and solving potential issues related to factors that might affect efficacy.

  9. UVA radiation is highly mutagenic in cells that are unable to repair 7,8-dihydro-8-oxoguanine in Saccharomyces cerevisiae.

    Science.gov (United States)

    Kozmin, S; Slezak, G; Reynaud-Angelin, A; Elie, C; de Rycke, Y; Boiteux, S; Sage, E

    2005-09-20

    UVA (320-400 nm) radiation constitutes >90% of the environmentally relevant solar UV radiation, and it has been proposed to have a role in skin cancer and aging. Because of the popularity of UVA tanning beds and prolonged periods of sunbathing, the potential deleterious effect of UVA has emerged as a source of concern for public health. Although generally accepted, the impact of DNA damage on the cytotoxic, mutagenic, and carcinogenic effect of UVA radiation remains unclear. In the present study, we investigated the sensitivity of a panel of yeast mutants affected in the processing of DNA damage to the lethal and mutagenic effect of UVA radiation. The data show that none of the major DNA repair pathways, such as base excision repair, nucleotide excision repair, homologous recombination, and postreplication repair, efficiently protect yeast from the lethal action of UVA radiation. In contrast, the results show that the Ogg1 DNA glycosylase efficiently prevents UVA-induced mutagenesis, suggesting the formation of oxidized guanine residues. Furthermore, sequence analysis of UVA-induced canavanine-resistant mutations reveals a bias in favor of GC-->TA events when compared with spontaneous or H(2)O(2)-, UVC-, and gamma-ray- induced canavanine-resistant mutations in the WT strain. Taken together, our data point out a major role of oxidative DNA damage, mostly 7,8-dihydro-8-oxoguanine, in the genotoxicity of UVA radiation in the yeast Saccharomyces cerevisiae. Therefore, the capacity of skin cells to repair 7,8-dihydro-8-oxoguanine may be a key parameter in the mutagenic and carcinogenic effect of UVA radiation in humans.

  10. Effects of bioactive compounds on senescence and components of senescence associated secretory phenotypes in vitro.

    Science.gov (United States)

    Mária, Janubová; Ingrid, Žitňanová

    2017-07-19

    Senescence is a permanent cell cycle arrest that is accompanied by changes in cell morphology and physiology occurring in vitro and in vivo. Senescence evolved as a beneficial response to damage promoting wound healing, limiting fibrosis, fighting against cancer and helping embryonic development. However, excessive accumulation of senescent cells is considered to play a substantial role in the development of aging-related diseases and other morphological and physiological changes associated with aging. Therefore, the aim of many researchers is to find out a way to eliminate senescent cells and improve the health condition of aging people. Bioactive compounds e.g. polyphenols, vitamins, phenols, carotenoids, ginsenosides, omega-3 fatty acids, and compounds isolated from algae (phloroglucinol, sargachromal) are known to affect important biological functions. Recent in vitro studies have revealed that they can protect different types of cells against stress induced senescence (SISP), delay replicative senescence, rejuvenate senescent cells and exert senolytic effects. This review summarizes how the biological compounds listed above affect cell morphology, cell proliferation, specific cell functions, the activity of senescence-associated β-galactosidase (SA-β-gal), the shortening of telomeres and reduction of telomerase activity, production of intracellular reactive oxygen species (ROS) and lipid peroxidation products, expression of antioxidant enzymes, expression of p53 and p21 - key effectors of cell cycle arrest leading to senescence - and expression of some key components of senescence associated secretory phenotype (SASP) in replicative senescence, stress induced senescence (SISP) and under conditions which may lead to the development of senescence such as UV-A and UV-B irradiation of cells and the production of matrix metalloproteinases (a component of the SASP) in cells. Finally, future perspectives of this research are discussed.

  11. Retrieval of the aerosol optical thickness from UV global irradiance measurements

    Science.gov (United States)

    Costa, M. J.; Salgueiro, V.; Bortoli, D.; Obregón, M. A.; Antón, M.; Silva, A. M.

    2015-12-01

    The UV irradiance is measured at Évora since several years, where a CIMEL sunphotometer integrated in AERONET is also installed. In the present work, measurements of UVA (315 - 400 nm) irradiances taken with Kipp&Zonen radiometers, as well as satellite data of ozone total column values, are used in combination with radiative transfer calculations, to estimate the aerosol optical thickness (AOT) in the UV. The retrieved UV AOT in Évora is compared with AERONET AOT (at 340 and 380 nm) and a fairly good agreement is found with a root mean square error of 0.05 (normalized root mean square error of 8.3%) and a mean absolute error of 0.04 (mean percentage error of 2.9%). The methodology is then used to estimate the UV AOT in Sines, an industrialized site on the Atlantic western coast, where the UV irradiance is monitored since 2013 but no aerosol information is available.

  12. Orally administered Polypodium leucotomos extract decreases psoralen-UVA-induced phototoxicity, pigmentation, and damage of human skin

    NARCIS (Netherlands)

    Middelkamp-Hup, Maritza A.; Pathak, Madhu A.; Parrado, Concepcion; Garcia-Caballero, Tomas; Rius-Díaz, Francisca; Fitzpatrick, Thomas B.; González, Salvador

    2004-01-01

    BACKGROUND: The use of psoralen-UVA (PUVA) in patients of skin phototype I to II is limited by side effects of acute phototoxicity and possible long-term carcinogenesis. OBJECTIVE: We sought to assess oral Polypodium leucotomos (PL) extract in decreasing PUVA-induced phototoxicity of human skin on a

  13. UvA Rescue - Team Description Paper - Virtual Robot competition - Rescue Simulation League RoboCup Iran Open 2014

    NARCIS (Netherlands)

    Visser, A.

    2014-01-01

    This year the task of the UvA Rescue Team is to break up the monolith architecture of the control architecture. On the one hand this will make the existing modules reusable by other researchers; on the other hand it opens the possibility to incorporate efficient modules from other research groups. A

  14. UvA Rescue team description paper: Virtual Robot competition, Rescue Simulation League, RoboCup 2012

    NARCIS (Netherlands)

    Visser, A.; Dijkshoorn, N.; van Noort, S.; Zwennes, O.; de Waard, M.; Katt, S.; Rozeboom, R.

    2012-01-01

    This year's contribution of the UvA Rescue Team is twofold. On the one hand a contribution is made to infrastructure of the Virtual Robot competition [1]. On the other hand progress is made with visual mapping with a ying platform. The progress was not only shown on the RoboCup, but in addition also

  15. Effciency and safety of the use of long-wave UVA-1 phototherapy in treatment of psoriasis

    Directory of Open Access Journals (Sweden)

    Bakulev A.L.

    2012-06-01

    Full Text Available

     

     

    The effectiveness of the long wavelength ultraviolet therapy (UVA-1 in complex treatment of patients with psoriasis has been studied during the research. There 20 patients with moderately severe and severe psoriasis in the phase of progressive dermatosis have been observed. The therapy was organized using photobox Waldmann UV-7001K (Herbert Waldmann GmbH & Co, Germany and F85 100W-TL10R lamps, creating radiation spectrum of UVA-1 (ƛ = 340 – 400 nm and emission maximum was ƛ=370 nm. 20 patients of the comparison group receive standard therapy in combination with PUVA therapy. The group did not differ from the main group of patients in age, duration and form of the disease. The effectiveness of the treatment was measured according to the dynamic assessment of PASI index. The usage of a long wavelength ultraviolet therapy (UVA-1 has caused a reduction of the severity and the extent of skin lesions, gave positive outcomes in all patients of the study. No adverse effects caused by the therapy undertaken have been noted. The administration of long wavelength ultraviolet therapy (UVA-1 is safe and effective in patients with psoriasis.

  16. Nieuwe ontdekkingen en mogelijkheden in het onderzoek aan Scholeksters dankzij het UvA Bird Tracking Systeem

    NARCIS (Netherlands)

    Ens, B. J.; Bom, R. A.; Dokter, A. M.; Oosterbeek, K.; de Jong, Jan; Bouten, W.

    2014-01-01

    This paper reports on new discoveries and new possibilities due to the deployment of the UvA Bird Tracking System (UvA-BiTS; Bouten et al. 2013) in our investigations of the behavioural ecology of Oystercatchers. This GPS tracker is powered by solar cells and not only stores GPS locations, but also

  17. Eutypa lata, causal agent of dieback in red currant (Ribes rubrum) and gooseberry (R. uva-crispa) in the Netherlands

    NARCIS (Netherlands)

    Wenneker, M.; Raak, van M.; Brouwershaven, van I.R.; Martin, W.S.; Kox, L.F.F.

    2011-01-01

    Dieback of red currant (Ribes rubrum) and gooseberry (Ribes uva-crispa) is an increasing problem in commercial fields in the Netherlands. Field surveys were done in 2006–2007 and samples with dieback symptoms were analysed. In this study the causal agent was diagnosed as Eutypa lata, based on

  18. Five Board Games for the Language Classroom: Uvas, Montana Rusa, El Futbol, La Corrida de Verbos, Paso a Paso.

    Science.gov (United States)

    Snyder, Barbara

    A collection of five board games for the Spanish language classroom contains gameboards, game markers, and directions for each game. It also contains general instructions for the teacher about the classroom use of board games. The games include: "Uvas," for use in vocabulary development and cultural awareness; "Montana Rusa," for general…

  19. Irradiation Facilities at CERN

    CERN Document Server

    Gkotse, Blerina; Carbonez, Pierre; Danzeca, Salvatore; Fabich, Adrian; Garcia, Alia, Ruben; Glaser, Maurice; Gorine, Georgi; Jaekel, Martin, Richard; Mateu,Suau, Isidre; Pezzullo, Giuseppe; Pozzi, Fabio; Ravotti, Federico; Silari, Marco; Tali, Maris

    2017-01-01

    CERN provides unique irradiation facilities for applications in many scientific fields. This paper summarizes the facilities currently operating for proton, gamma, mixed-field and electron irradiations, including their main usage, characteristics and information about their operation. The new CERN irradiation facilities database is also presented. This includes not only CERN facilities but also irradiation facilities available worldwide.

  20. Analysis and sensory evaluation of gooseberry (Ribes uva crispa L.) volatiles.

    Science.gov (United States)

    Hempfling, Katrin; Fastowski, Oxana; Kopp, Markus; Nikfardjam, Martin Pour; Engel, Karl-Heinz

    2013-07-03

    Volatiles of gooseberries (Ribes uva cripsa L.) were isolated by means of vacuum-headspace-extraction, and the obtained concentrates were analyzed via capillary gas chromatography-mass spectrometry. To ensure the quantitation of highly volatile compounds, headspace analysis was additionally performed on selected batches. C₆-components (e.g., (Z)-hex-3-enal, (E)-hex-2-enal), derived from lipid oxidation, and short-chain esters (e.g., ethyl acetate, methyl butanoate, ethyl butanoate) turned out to be the major compound classes in the fresh fruit. The compositional variability was demonstrated by analyzing several gooseberry varieties at different stages of ripeness. The contributions of volatiles to the gooseberry aroma were assessed by using gas chromatography-olfactometry in combination with aroma extract dilution analysis and calculation of odor activity values. C₆-components and esters were shown to be responsible for the green and fruity character of fresh gooseberries.

  1. Evaluación sensorial del vino artesanal de uva Isabella (Vitis labrusca L.)

    OpenAIRE

    Pedro José Almanza-Merchán; Andrea Johana Reyes-M.; Marco Luis Ayala; William Balaguera-L.; Pablo Antonio Serrano-Cely

    2015-01-01

    El consumo de vino en Colombia se ha incrementado durante los últimos años, en especial el de los vinos tinto. A pesar de las pocas características vínicas de la uva Isabella (Vitis labrusca L.), su bajo contenido de azúcares y su alta concentración de ácidos le otorgan el potencial para la elaboración de un vino que presenta sabores y aromas intensos. La combinación de color, aroma y sabor provoca la denominada textura del vino. El análisis sensorial de los vinos, a través de catas, da orige...

  2. UVA-UVB photoprotective activity of topical formulations containing Morinda citrifolia extract.

    Science.gov (United States)

    Serafini, Mairim Russo; Detoni, Cassia Britto; Menezes, Paula dos Passos; Pereira Filho, Rose Nely; Fortes, Vanessa Silveira; Vieira, Maria José Fonseca; Guterres, Sílvia Stanisçuaski; Cavalcanti de Albuquerque Junior, Ricardo Luiz; Araújo, Adriano Antunes de Souza

    2014-01-01

    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 of M. citrifolia topical 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.

  3. Detecting free radicals in sunscreens exposed to UVA radiation using chemiluminescence.

    Science.gov (United States)

    Millington, Keith R; Osmond, Megan J; McCall, Maxine J

    2014-04-05

    One of the current concerns with the application of nanoparticles in sunscreens, and in particular nano-TiO2 and ZnO, is their potential to photogenerate free radicals and reactive oxygen species (ROS) when they absorb ultraviolet wavelengths from sunlight. Free radicals and ROS are known to be associated with UV-induced skin damage and oxidative stress, from which sunscreens are expected to offer significant protection. Here we describe a simple method, based on chemiluminescence emission, for detecting free radicals generated in commercial sunscreens alone, and when applied to various substrates, following exposure to UVA (320-400nm) radiation. This photo-induced chemiluminescence (PICL) technique could be used to optimise sunscreen formulations so as to minimise free radical photogeneration during exposure to sunlight. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  4. HPTLC densitometric analysis of arbutin in bulk drug and methanolic extracts of Arctostaphylos uva-ursi.

    Science.gov (United States)

    Alam, P; Alqasoumi, S I; Shakeel, F; Abdel-Kader, M S

    2011-10-01

    A high-performance thin layer chromatographic densitometric method for the analysis of arbutin was developed and validated in the present investigation. Arbutin was separated on aluminium-backed silica gel 60 F(254) plates with methanol : chloroform (3:7)% (v/v) as the mobile phase. This system was found to give a compact spot of arbutin at a retention factor (R(f)) value of 0.32 ± 0.02. The limit of detection and limit of quantification were found to be 35.42 and 106.26 ng/spot, respectively. The proposed method with a high degree of precision and accuracy was employed for the analysis of arbutin in the bulk drug and methanolic extract of Arctostaphylos uva-ursi.

  5. Structural and biomechanical effects of photooxidative collagen cross-linking with photosensitizer riboflavin and 370 nm UVA light on human corneoscleral tissues.

    Science.gov (United States)

    Choi, Samjin; Shin, Jae-Ho; Cheong, Youjin; Jin, Kyung-Hyun; Park, Hun-Kuk

    2013-10-01

    This study quantitatively investigated the immediate effects of a photooxidative collagen cross-linking treatment with photosensitizer riboflavin (RF) and 370 nm UVA light in in vitro human corneoscleral collagen fibrils using histology, thickness, scanning electron microscopy, and atomic force microscopy analyses. Twenty 8 x 2 mm corneoscleral strips were dissected sagittally from donor tissue using a scalpel. Four parameters were investigated, including the density, thickness, adhesion force, and stiffness of corneoscleral tissues before and after the collagen cross-linking treatment. The RFUVA-catalyzed collagen cross-linking treatment led to an increase in the density of both corneal (8%) and scleral (23%) stromal collagens. However, there was no difference in corneoscleral thickness. Furthermore, RFUVA-catalyzed collagen cross-linking treatment led to an increased biomechanical response of corneosclera: 25 and 8% increases in corneoscleral stiffness, and 24 and 22% increases in corneoscleral adhesion force. The collagen cross-linking treatment through RF-sensitized photoreaction may cause structural and biomechanical changes in the collagen fibril network of the cornea and the sclera. This is due to narrowing of the interfibrillar spacing and the stromal edema.

  6. UVA Photoirradiation of Halogenated-Polycyclic Aromatic Hydrocarbons Leading to Induction of Lipid Peroxidation

    Directory of Open Access Journals (Sweden)

    Peter P. Fu

    2006-06-01

    Full Text Available Since the finding in the 1930s, a large number of polycyclic aromatic hydrocarbons (PAHs of different structures have been tested for potential tumorigenicity. Structure-activity relationships of halo-PAHs have been investigated to determine the regions of a PAH that may be involved in cancer initiation. From these studies, a number of halo-PAHs were found to be tumorigenic in experimental animals. It was not until the 1980s that halo-PAHs were found to be present in the environment, including municipal incinerator fly ash, urban air, coal combustion, soil, snow, automobile exhausts, and tap water. Due to their widespread presence in the environment and their genotoxic activities, including carcinogenicity, many of these compounds may pose a health risk to humans. Although the biological activities, including metabolism, mutagenicity, and carcinogenicity, of halo-PAHs have been studied their phototoxicity and photo-induced biological activity have not been well examined. In this study, we study the photoirradiation of a series of structure-related halo-PAHs by UVA light in the presence of a lipid, methyl linoleate, and determine as to whether or not these compounds can induce lipid peroxidation. The halo-PAHs chosen for study include 2-bromonaphthalene, 1-chloroanthracene, 9,10-dibromoanthracene, 9-chlorophenanthrene, 9-bromophenanthrene, 7-chlorobenz[a]anthracene, 7-bromobenz[a]anthracene, 7-bromo-5-methylbenz[a]anthracene, 6-chlorobenzo[a]pyrene, and 6-bromobenzo[a]pyrene. The results indicate that upon photoirradiation by UVA all these compounds induced lipid peroxidation at different levels. These results suggest that halo-PAHs may be harmful to human health.

  7. [Polymorphic light eruption: prophylaxis using a topical combination of antioxidants and UVA protection formulations].

    Science.gov (United States)

    Jeanmougin, M; Peyron, J-L; Thomas, P; Beani, J-C; Guez, E; Bachot, N

    2006-05-01

    In a recent randomized, double-blind, placebo-controlled clinical study, the efficacy of a combination consisting of 0.25% alpha-glucosyl-rutin, 1% vitamin E and a broad-spectrum, highly UVA-protective sunscreen (sun protector factor 15 - persistent pigmentation darkening 6) regarding prevention of polymorphous light eruption was well demonstrated. We evaluated this combination under real solar exposure conditions. Patients with three previous typical polymorphous light eruptions (including one in the last year) were included in an open prospective multicenter study. The preparation was applied every two hours after the first summer exposure. No topical or systemic treatments presumed to be effective against polymorphous light eruption were given concomitantly. Evaluation was performed after the summer by a dermatologist. Two of the 54 patients dropped out of the study, one for an adverse effect (contact dermatitis). At the end of the study following application of the test preparation, no eruption was seen for 35 patients (67%), with minor eruption for 10 patients (19%) and an marked eruption for 7 patients (13%). Pruritus (present in all patients the year before) was not seen in 36 patients (69%), was considered bearable for 36 patients and unbearable for only 3 patients compared to 27 before inclusion. For the dermatologists, efficacy was excellent for 35 patients and good for 7 patients, giving global efficacy of around 80%, with inadequate results in 10% of cases (5 patients). Concerning protection against erythema, the test product reduced sunburn by 60% compared with the previous year. Because of the high clinical efficacy of the product noted after UVA challenge tests and verified by this clinical study under actual conditions of exposure, it may be proposed as a new prophylactic treatment for polymorphous light eruption.

  8. Evaluación sensorial del vino artesanal de uva Isabella (Vitis labrusca L.

    Directory of Open Access Journals (Sweden)

    Pedro José Almanza-Merchán

    2015-07-01

    Full Text Available El consumo de vino en Colombia se ha incrementado durante los últimos años, en especial el de los vinos tinto. A pesar de las pocas características vínicas de la uva Isabella (Vitis labrusca L., su bajo contenido de azúcares y su alta concentración de ácidos le otorgan el potencial para la elaboración de un vino que presenta sabores y aromas intensos. La combinación de color, aroma y sabor provoca la denominada textura del vino. El análisis sensorial de los vinos, a través de catas, da origen a una escala entre los vinos y a una descripción que genera cierto impacto en el posicionamiento de este licor en el mercado. Esta investigación buscó evaluar la calidad organoléptica del vino artesanal de uva Isabella, mediante una cata a ciegas. Se evaluaron tres tipos de vino; dos producidos en la Universidad Pedagógica y Tecnológica de Colombia (semiseco y semidulce y uno procedente del municipio de Cerrito, Valle del Cauca. El panel conformado por 20 catadores evaluó los vinos de acuerdo con los parámetros establecidos por el Concurso Internacional de Vinos y Espirituosos (CINVE. Los resultados presentaron diferencias significativas entre el vino Portal del Paraíso® y los vinos Uptc. Los vinos Uptc obtuvieron la menor puntuación, catalogándolos, de acuerdo con el CINVE, como los mejores sensorialmente.

  9. Tendências climáticas e produção de uva na região dos Vales da Uva Goethe

    Directory of Open Access Journals (Sweden)

    Álvaro José Back

    2012-04-01

    Full Text Available O objetivo deste trabalho foi avaliar tendências nas séries climáticas e nos índices agroclimáticos para o cultivo da videira na região dos Vales da Uva Goethe, em Santa Catarina. A região apresenta clima mesotérmico úmido. Foram utilizados dados de temperatura máxima e mínima do ar, do período de 1924 a 2010, e de precipitação pluvial, de 1955 a 2010. O teste de Mann‑Kendall foi utilizado para avaliar a tendência nas séries, cuja magnitude foi estimada pela declividade mediana determinada pelo teste de Theil-Sen. Foi observada tendência de aumento nas séries de temperatura mínima do ar, em escala anual, bem como nas estações do ano. Quanto à temperatura máxima, somente houve tendência de aumento na série de verão. Em relação aos índices agrometeorológicos, foi observada tendência de diminuição do número de geadas, diminuição do período entre a brotação e a colheita, aumento da soma térmica e dos índices de Huglin e de frio. Foram evidenciadas tendências de aumento da precipitação pluvial total anual e da precipitação no período de crescimento da videira, bem como aumento do número de dias, com chuva igual ou superior a 20 mm, e aumento na temperatura mínima e noturna.

  10. Efeitos da terapia fotodinâmica e de uma única aplicação de laser de baixa potência em bactérias in vitro Effects of photodynamic therapy and of a sole low-power laser irradiation on bacteria in vitro

    Directory of Open Access Journals (Sweden)

    Rogério Gubert Benvindo

    2008-01-01

    Full Text Available O laser de baixa potência vem sendo usado para acelerar a cicatrização em úlceras de pressão devido a seus efeitos cicatrizante, antiinflamatório, antiedematoso e analgésico. No entanto, não há consenso quanto a seu efeito em úlceras infectadas. O objetivo deste estudo foi verificar o efeito bactericida da laserterapia e da terapia fotodinâmica (TFD com laser de baixa potência, InGaP, 670 nm, em doses de 2, 4 e 6 J/cm², em bactérias gram-positivas e gram-negativas in vitro. Foram preparadas 32 placas de Petri com bactérias, 16 com Pseudomonas aeruginosa e 16 com Staphilococcus aureus. Aleatoriamente dividiu-se cada grupo em oito subgrupos (duas placas cada: três subgrupos tratados só com laserterapia, em doses de 2 J/cm², 4 J/cm² e 6 J/cm²; três subgrupos tratados com TFD, em doses de 2 J/cm², 4 J/cm² e 6 J/cm²; um tratado apenas com fotossensibilizante (azul de metileno a 0,1 µg/ml; e um subgrupo não tratado (controle. Os subgrupos laser e TFD foram irradiados uma única vez e incubados por 24 horas. Os outros dois subgrupos não receberam irradiação. As culturas foram analisadas visualmente para verificação ou não do halo de inibição. Em todos os subgrupos, de ambas as bactérias, não foi observado qualquer halo de inibição nem de crescimento. Conclui-se que a terapia a laser e a fotodinâmica de baixa potência (InGaP, 670 nm não produziram efeitos bactericidas e/ou bacteriostáticos, tampouco tendo havido efeito bioestimulante sobre as bactérias.Low-level laser therapy has been used to speed up healing process of pressure ulcers due to its antiinflammatory, analgesic, anti-edematous, and scarring effects. However there is no consensus on its effect on infected ulcers. The aim of this study was to verify the bactericidal effect of low-level laser therapy (InGaP, 670 nm and photodynamic therapy (PDT at 2, 4 and 6 J/cm² doses, onto gram-negative and gram-positive bacteria in vitro. Thirty two Petri plates

  11. Effect of 8-MOP plus UVA treatment on survival and repair of plasmid pBR322; Efecto del tratamiento con 8-MOP mas UVA en la supervivencia y reparacion de pBR322

    Energy Technology Data Exchange (ETDEWEB)

    Bauluz, C.; Vidania, R. de

    1991-07-01

    We have studied the lethality produced in pBR322 DNA after PUVA treatment (8-MOP+UVA). As recipients, we used a collection of E. coli strains differing in their repair capacities and analysed the involvement of several DNA repair pathways in the removal of plasmid lesions. We have also studied the effect of UVA radiation alone, in order to determine more precisely the effect attributable only to psoralen molecules. Results showed a strong lethal effect derived from PUVA treatment; however, some plasmid recovery was achieved in bacterial hosts proficient in Excision repair and SOS repair. Another repair pathway, only detectable at high density of lesions, appeared to be relevant for the removal of 8-MOP:DNA adducts.(Author) 11 refs.

  12. Nd:YAG laser irradiation on temporary teeth carious tissue using 12% diamine silver fluoride as a photo-absorber - a morphological study; Estudo comparativo morfologico da acao do laser de Nd:YAG em dentina cariada de dentes deciduos in vitro, condicionados com diamino fluoreto de prata a 12% e carvao mineral

    Energy Technology Data Exchange (ETDEWEB)

    Calmon, Andrea de Avillez

    2001-07-01

    Since Nd:YAG laser radiation was first introduced in Dentistry various photo-absorbers were employed with the intent of improving its efficacy when used on dental carious tissue. The purpose of the present study was to analyze the influence of this radiation using Scanning and Optical microscopy over carious tissue of primary teeth using two photo-absorbers. 15 primary human teeth were used and, in each one, 3 cavity preparations were performed. Specimens were then submitted to an in vitro demineralizing environment during 18 days. Two of the cavities of each specimen were laser irradiated using the Nd:YAG laser with 60 mJ of energy per pulse, 10 Hz and average power of 0,6 W. The 12% diamine silver fluoride or the mineral coal were used as photo-absorbers. The third cavity of the specimens was used as a control and received no laser irradiation. Samples were transversally cut and the section analyzed by SEM and OM. Results showed that the 12% diamine silver fluoride is an efficient photo-absorber and, when used it the Nd:YAG laser, leading to melting and resolidification of the carious tissue. It can be concluded that the 12% diammine silver fluoride presents advantages over the mineral coal as a photo absorber when used in primary teeth as it promotes and improves the efficacy of laser irradiation. This substance also works as a barrier on the carie progression in deeper areas such as the infected and necrotic zones. (author)

  13. Inhibitory effects of ambient levels of solar UV-A and UV-B radiation in growth of cv. New Red Fire lettuce

    Energy Technology Data Exchange (ETDEWEB)

    Krizek, D.T.; Britz, S.J.; Mirecki, R.M. [Climate Stress Laboratory, Beltsville, MD (United States)

    1998-05-01

    The influence of solar UV-A and UV-B radiation at Beltsville, MD, USA, on growth of Lactuca sativa L. (cv. New Red Fire lettuce) was examined during early summer of 1996 and 1997. Plants were grown from seed in plastic window boxes covered with Llumar to exclude UV-A and UV-B, polyester to exclude UV-B, or tefzel (1996) or teflon (1997) to transmit UV-A and UV-B radiation. After 31-34 days, plants grown in the absence of solar UV-B radiation (polyester) had 63 and 57% greater fresh weight and dry weight of tops, respectively, and 57, 72 and 47% greater dry weight of leaves, stems and roots, respectively, as compared to those grown under ambient UV-B (tefzel or teflon). Plants protected from UV-A radiation as well (Llumar) showed an additional 43 and 35% increase, respectively, in fresh and dry weight of tops and a 33 and 33% increase, respectively, in dry weight of leaves and stems, but no difference in root biomass over those grown under polyester. Excluding ambient UV-B (polyester) significantly reduced the UV absorbance of leaf extracts at 270, 300 and 330 nm (presumptive flavonoids) and the concentration of anthocyantins at 550 nm as compared to those of leaf extract from plants grown under ambient UV-A and UV-B. Additional removal of ambient UV-A (Llumar) reduced the concentration of anthocyanins, but had no further effect on UV absorbance at 270, 300 or 330 nm. These findings provide evidence that UV-B radiation is more important than UV-A radiation for flavonoid induction in this red-pigmented lettuce cultivar. Although previous workers have obtained decreases in lettuce yield under enhanced UV-B, this is the first evidence for inhibitory effects of solar UV-A and UV-B radiation on lettuce growth. (au) 34 refs.

  14. Influence of constant current stress on the conduction mechanisms of reverse leakage current in UV-A light emitting diodes

    Science.gov (United States)

    Wang, Yingzhe; Zheng, Xuefeng; Dai, Feng; Zhu, Jiaduo; Li, Peixian; Ma, Xiaohua; Hao, Yue

    2017-12-01

    The influence of constant current stress on the conduction mechanism of reverse leakage current in ultraviolet (UV) light emitting diodes (LEDs) in the UV-A spectral range has been investigated for the first time using temperature-dependent current-voltage measurement from 370 K to 55 K. Below 220 K, variable range hopping mechanism dominates in UV-A LEDs. While, above 220 K, the leakage current is attributed to Poole-Frenkel emission mechanism within the bias range of -3 ∼ -6 V. With the increasing of the reverse bias, the conduction mechanism transforms from Poole-Frenkel emission to space-charge-limited conduction mechanism. In particular, applying electrical stress yields an alteration of the transition voltage from -7.5 V to -6.5 V. We propose that stress could lead to a reduction of the thermal activation energy, and therefore alters the transition voltage.

  15. Reconstruction of daily solar UV irradiation from 1893 to 2002 in Potsdam, Germany.

    Science.gov (United States)

    Junk, Jürgen; Feister, Uwe; Helbig, Alfred

    2007-08-01

    Long-term records of solar UV radiation reaching the Earth's surface are scarce. Radiative transfer calculations and statistical models are two options used to reconstruct decadal changes in solar UV radiation from long-term records of measured atmospheric parameters that contain information on the effect of clouds, atmospheric aerosols and ground albedo on UV radiation. Based on earlier studies, where the long-term variation of daily solar UV irradiation was derived from measured global and diffuse irradiation as well as atmospheric ozone by a non-linear regression method [Feister et al. (2002) Photochem Photobiol 76:281-293], we present another approach for the reconstruction of time series of solar UV radiation. An artificial neural network (ANN) was trained with measurements of solar UV irradiation taken at the Meteorological Observatory in Potsdam, Germany, as well as measured parameters with long-term records such as global and diffuse radiation, sunshine duration, horizontal visibility and column ozone. This study is focussed on the reconstruction of daily broad-band UV-B (280-315 nm), UV-A (315-400 nm) and erythemal UV irradiation (ER). Due to the rapid changes in cloudiness at mid-latitude sites, solar UV irradiance exhibits appreciable short-term variability. One of the main advantages of the statistical method is that it uses doses of highly variable input parameters calculated from individual spot measurements taken at short time intervals, which thus do represent the short-term variability of solar irradiance.

  16. UVA, UVB Light, and Methyl Jasmonate, Alone or Combined, Redirect the Biosynthesis of Glucosinolates, Phenolics, Carotenoids, and Chlorophylls in Broccoli Sprouts

    Directory of Open Access Journals (Sweden)

    Melissa Moreira-Rodríguez

    2017-11-01

    Full Text Available Broccoli sprouts contain health-promoting phytochemicals that can be enhanced by applying ultraviolet light (UV or phytohormones. The separate and combined effects of methyl jasmonate (MJ, UVA, or UVB lights on glucosinolate, phenolic, carotenoid, and chlorophyll profiles were assessed in broccoli sprouts. Seven-day-old broccoli sprouts were exposed to UVA (9.47 W/m2 or UVB (7.16 W/m2 radiation for 120 min alone or in combination with a 25 µM MJ solution, also applied to sprouts without UV supplementation. UVA + MJ and UVB + MJ treatments increased the total glucosinolate content by ~154% and ~148%, respectively. MJ induced the biosynthesis of indole glucosinolates, especially neoglucobrassicin (~538%, showing a synergistic effect with UVA stress. UVB increased the content of aliphatic and indole glucosinolates, such as glucoraphanin (~78% and 4-methoxy-glucobrassicin (~177%. UVA increased several phenolics such as gallic acid (~57% and a kaempferol glucoside (~25.4%. MJ treatment decreased most phenolic levels but greatly induced accumulation of 5-sinapoylquinic acid (~239%. MJ treatments also reduced carotenoid and chlorophyll content, while UVA increased lutein (~23%, chlorophyll b (~31%, neoxanthin (~34%, and chlorophyll a (~67%. Results indicated that UV- and/or MJ-treated broccoli sprouts redirect the carbon flux to the biosynthesis of specific glucosinolates, phenolics, carotenoids, and chlorophylls depending on the type of stress applied.

  17. Puesta a punto del método de PCR en tiempo real para la cuantificación de Aspergillus carbonarius en uvas Vitis vinifera cv. Tannat

    Directory of Open Access Journals (Sweden)

    Gustavo Garmendia

    2011-12-01

    Full Text Available La ocratoxina A (OTA es una micotoxina que ha sido detectada en uvas y vinos. Es producida por Aspergillus ochraceus, Penicillium verrucosum, Aspergillus carbonarius y especies pertenecientes al agregado Aspergillus niger. En los últimos años se ha descrito la presencia de Aspergillus aculeatus y Aspergillus japonicus en la superficie de uvas y su capacidad de producir OTA. A pesar de que la concentración detectada de cepas pertenecientes a la Sección Nigri fue < 100/g de uva, se han aislado, identificado y caracterizado 56 cepas de Aspergillus pertenecientes a la Sección Nigri. El 51 % fue identificado como A. niger, el 39 % como A. japonicus, 5 % como A. tubingensis -like y 5 % como A. foetidus. Ninguna cepa de A. carbonarius fue aislada. Debido a que esta especie ha sido descrita como la principal responsable de la presencia de OTA en uvas y vinos por su capacidad de producir altas concentraciones de OTA, se requiere un método más sensible que los métodos convencionales para detectar y cuantificar la presencia de A. carbonarius en uva. En este trabajo se optimizó la técnica de PCR en tiempo real para la detección y cuantificación de esta especie en uvas d e la variedad Tannat.

  18. Produtividade e composição de uva e de vinho de videiras consorciadas com plantas de cobertura

    Directory of Open Access Journals (Sweden)

    Jovani Zalamena

    2013-02-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência de plantas de cobertura verde sobre a produtividade das videiras e sobre a composição da uva e do vinho. Durante duas safras, foram feitas avaliações de três tipos de consórcio, dois manejos das coberturas e de um tratamento controle, com plantas espontâneas controladas por herbicidas e roçagem. Utilizou-se vinhedo de uvas 'Cabernet Sauvignon', localizado a 1.130 m de altitude, em um Cambissolo Húmico distrófico, em São Joaquim, SC. Os consórcios foram realizados com a sucessão de cultivos anuais de moha (Setaria italica com azevém (Lolium multiflorum e de trigo mourisco (Fagopyrum esculentum com aveia‑branca (Avena sativa, bem como com a planta perene festuca (Fetusca sp.. Os manejos consistiram da transferência ou não do resíduo cultural da linha para a entrelinha. As videiras apresentaram maior produtividade de uva no consórcio com as plantas anuais, em comparação ao tratamento controle, ou com a planta perene festuca. O manejo da cobertura verde não teve influência sobre as variáveis avaliadas. Os consórcios não influenciaram de forma consistente os teores de N da uva nem a composição do mosto, embora, na última safra, o teor de sólidos solúveis totais do mosto tenha sido maior nos tratamentos com consórcio, em comparação ao controle. Além disso, as videiras consorciadas com festuca podem proporcionar vinho com maior teor de antocianinas e polifenóis totais.

  19. PROSPECÇÃO TECNOLÓGICA: PROTETORES SOLARES ANTI UVA E ANTI UVB

    Directory of Open Access Journals (Sweden)

    Douglas Dourado Oliveira

    2014-03-01

    Full Text Available Com o aumento da temperatura no planeta devido o efeito estufa, há uma preocupação com as radiações ultravioletas que incidem na pele dos seres humanos. Diante disso a indústria cosmética vem desenvolvendo constantemente formulações contendo filtros solares, anti UVA, anti UVB e também os dois filtros associados numa mesma formulação, retardando o envelhecimento cutâneo, formação dos radicais livres e prevenindo uma grande problemática atual, o câncer de pele. O objetivo deste trabalho foi realizar uma prospecção para conhecimento do desenvolvimento científico e tecnológico relacionado à aplicação de filtros solares associados em uma mesma formulação baseando-se no número de patentes depositadas e de artigos publicados. A prospecção foi realizada no Banco Europeu de Patentes (EPO, no Banco Americano de Marcas e Patentes (USPTO e no Banco de dados do Instituto Nacional de Propriedade Industrial do Brasil (INPI, bem como nas bases de periódicos, CAPES, Pubmed, Science Direct e ACS Publications. O maior número de patentes foi depositado nos últimos 5 anos. As patentes em sua maioria estão classificadas em A61K. Os responsáveis por maior número de patentes foram os Estados Unidos, China e Japão. Há uma diminuição no número de depósitos de patentes quando se associou a UVA e UVB no fotoprotetor. Em relação à produção científica o número de publicações referente a formulações fotoprotetoras contendo os dois filtros associados é maior que o de depósito de patentes, porém segue o mesmo perfil de redução ao associar os filtros numa mesma formulação.

  20. Factors affecting photoreactivation in UVB-irradiated herbivorous spider mite (Tetranychus urticae).

    Science.gov (United States)

    Murata, Yasumasa; Osakabe, Masahiro

    2014-06-01

    Ambient ultraviolet-B (UVB) radiation causes lethal damage to spider mites, and the extent of photochemical effects is determined by cumulative irradiance in the two-spotted spider mite, Tetranychus urticae. However, the LD50 values obtained using a UVB lamp were much lower than those elicited by solar UVB radiation. As solar radiation includes intense visible light and UVA, we assumed that a photoreactivation mechanism would play a role to survive under solar radiation. We assessed the capacity for photoreactivation in T. urticae eggs and larvae, and found that the efficacy of photoreactivation was determined by the cumulative irradiance of visible light (VIS) after exposure to UVB radiation. The wavelength range effective for photoreactivation went from UVA to green. Next, we found that an increased time lag between UVB and VIS radiation reduced the photoreactivation efficacy in eggs. In contrast, a time lag ≤4 h did not affect that in larvae. We discussed the possibility that the timing of photoreactivation occurs related with phase-specific UVB vulnerability and outbreak symptoms due to UVB-induced DNA damage. Our results suggest that T. urticae depends on a photoreactivation mechanism, and that the photoreactivation efficiency probably caused the divergence in UVB impact between UV lamp and solar radiation.

  1. The Effect of NaCl and CMA on the Growth and Morphology of Arctostaphylos uva-ursi (Kinnikinnick

    Directory of Open Access Journals (Sweden)

    Jane P. Young

    2012-01-01

    Full Text Available Numerous studies have described the negative effects of the commonly used deicer, NaCl, on plants; this has led to research on less toxic alternatives, for example, calcium magnesium acetate (CMA. The present research investigated the native ground cover species, Arctostaphylos uva-ursi (kinnikinnick, as a possible candidate for landscaping in high salt conditions. The effect of NaCl and CMA on the growth, morphology, and survival of A. uva-ursi plants was examined to explore the use of CMA as a potential environmentally friendly alternative deicing agent to that of NaCl. The influence of these deicing agents on selected soil properties was also investigated. It was found that this ground cover species was able to tolerate moderate-to-high levels of NaCl and even greater concentrations of CMA. Therefore, A. uva-ursi proved to be a candidate for landscaping use in a north central city of Canada, where deicing agents are used in winter months.

  2. Effect of coupled UV-A and UV-C LEDs on both microbiological and chemical pollution of urban wastewaters

    Energy Technology Data Exchange (ETDEWEB)

    Chevremont, A.-C., E-mail: anne-celine.chevremont@imbe.fr [Aix-Marseille Universite - CNRS, FR ECCOREV, Laboratoire Chimie de l' Environnement (FRE3416), Equipe ' Developpements Metrologiques et Chimie des Milieux' , 3 place Victor Hugo, case 29, 13331 Marseille Cedex 3 (France); Aix-Marseille Universite - CNRS, FR ECCOREV, Institut Mediterraneen de Biodiversite et d' Ecologie marine et continentale (UMR7263), Equipe ' Vulnerabilite des Systemes Microbiens' , Avenue Escadrille Normandie-Niemen, Boite 452, 13397 Marseille Cedex 20 (France); Farnet, A.-M. [Aix-Marseille Universite - CNRS, FR ECCOREV, Institut Mediterraneen de Biodiversite et d' Ecologie marine et continentale (UMR7263), Equipe ' Vulnerabilite des Systemes Microbiens' , Avenue Escadrille Normandie-Niemen, Boite 452, 13397 Marseille Cedex 20 (France); Coulomb, B.; Boudenne, J.-L. [Aix-Marseille Universite - CNRS, FR ECCOREV, Laboratoire Chimie de l' Environnement (FRE3416), Equipe ' Developpements Metrologiques et Chimie des Milieux' , 3 place Victor Hugo, case 29, 13331 Marseille Cedex 3 (France)

    2012-06-01

    Wastewater reuse for irrigation is an interesting alternative for many Mediterranean countries suffering from water shortages. The development of new technologies for water recycling is a priority for these countries. In this study we test the efficiency of UV-LEDs (Ultraviolet-Light-Emitting Diodes) emitting UV-A or UV-C radiations, used alone or coupled, on bacterial and chemical indicators. We monitored the survival of fecal bioindicators found in urban wastewaters and the oxidation of creatinine and phenol which represent either conventional organic matter or the aromatic part of pollution respectively. It appears that coupling UV-A/UV-C i) achieves microbial reduction in wastewater more efficiently than when a UV-LED is used alone, and ii) oxidizes up to 37% of creatinine and phenol, a result comparable to that commonly obtained with photoreactants such as TiO{sub 2}. - Highlights: Black-Right-Pointing-Pointer We test UV-LEDs as an urban wastewater tertiary treatment. Black-Right-Pointing-Pointer UV-A and UV-C are coupled, combining germicidal and oxidative properties of UV. Black-Right-Pointing-Pointer Coupled wavelengths have the most efficient bactericidal effect. Black-Right-Pointing-Pointer Coupling UV-A and UV-C leads to photooxidation of creatinine and phenol.

  3. Bystander apoptosis in human cells mediated by irradiated blood plasma

    Energy Technology Data Exchange (ETDEWEB)

    Vinnikov, Volodymyr, E-mail: vlad.vinnikov@mail.ru [Grigoriev Institute for Medical Radiology of the National Academy of Medical Science of Ukraine (Ukraine); Lloyd, David; Finnon, Paul [Centre for Radiation, Chemical and Environmental Hazards of the Health Protection Agency of the United Kingdom (United Kingdom)

    2012-03-01

    Following exposure to high doses of ionizing radiation, due to an accident or during radiotherapy, bystander signalling poses a potential hazard to unirradiated cells and tissues. This process can be mediated by factors circulating in blood plasma. Thus, we assessed the ability of plasma taken from in vitro irradiated human blood to produce a direct cytotoxic effect, by inducing apoptosis in primary human peripheral blood mononuclear cells (PBM), which mainly comprised G{sub 0}-stage lymphocytes. Plasma was collected from healthy donors' blood irradiated in vitro to 0-40 Gy acute {gamma}-rays. Reporter PBM were separated from unirradiated blood with Histopaque and held in medium with the test plasma for 24 h at 37 Degree-Sign C. Additionally, plasma from in vitro irradiated and unirradiated blood was tested against PBM collected from blood given 4 Gy. Apoptosis in reporter PBM was measured by the Annexin V test using flow cytometry. Plasma collected from unirradiated and irradiated blood did not produce any apoptotic response above the control level in unirradiated reporter PBM. Surprisingly, plasma from irradiated blood caused a dose-dependent reduction of apoptosis in irradiated reporter PBM. The yields of radiation-induced cell death in irradiated reporter PBM (after subtracting the respective values in unirradiated reporter PBM) were 22.2 {+-} 1.8% in plasma-free cultures, 21.6 {+-} 1.1% in cultures treated with plasma from unirradiated blood, 20.2 {+-} 1.4% in cultures with plasma from blood given 2-4 Gy and 16.7 {+-} 3.2% in cultures with plasma from blood given 6-10 Gy. These results suggested that irradiated blood plasma did not cause a radiation-induced bystander cell-killing effect. Instead, a reduction of apoptosis in irradiated reporter cells cultured with irradiated blood plasma has implications concerning oncogenic risk from mutated cells surviving after high dose in vivo irradiation (e.g. radiotherapy) and requires further study.

  4. Artificial aging of Uva di Troia and Primitivo wines using oak chips inoculated with Penicillium purpurogenum.

    Science.gov (United States)

    Petruzzi, Leonardo; Bevilacqua, Antonio; Ciccarone, Claudio; Gambacorta, Giuseppe; Irlante, Giuseppina; Lamacchia, Carmela; Sinigaglia, Milena

    2012-01-30

    Two red wines (Primitivo and Uva di Troia) treated with oak chips inoculated with Penicillium purpurogenum were analysed in order to assess their contents of furfural, cis-β-methyl-γ-octalactone, syringol, eugenol, vanillin and 4-vinylguaiacol. Two different sizes of oak chips (small and big, of length 2 and 8 mm respectively) and two different degrees of toasting (low and high) were used in the study. Aroma compounds were analysed by gas chromatography/mass spectrometry to determine differences among samples after 15 days of chip contact time. Big oak chips inoculated with P. purpurogenum increased the level of 4-vinylguaiacol, while small oak chips inoculated with P. purpurogenum, in some conditions, increased the level of eugenol. Chip size and degree of toasting also played an important role in the content of eugenol. The use of oak chips inoculated with mould might be a promising alternative to barrel aging. Moreover, different fungal inocula could contribute to the enrichment of wine with specific compounds (e.g. 4-vinylguaiacol and eugenol). Copyright © 2011 Society of Chemical Industry.

  5. UVA-induced reset of hydroxyl radical ultradian rhythm improves temporal lipid production in Chlorella vulgaris.

    Science.gov (United States)

    Balan, Ranjini; Suraishkumar, G K

    2014-01-01

    We report for the first time that the endogenous, pseudo-steady-state, specific intracellular levels of the hydroxyl radical (si-OH) oscillate in an ultradian fashion (model system: the microalga, Chlorella vulgaris), and also characterize the various rhythm parameters. The ultradian rhythm in the endogenous levels of the si-OH occurred with an approximately 6 h period in the daily cycle of light and darkness. Further, we expected that the rhythm reset to a shorter period could rapidly switch the cellular redox states that could favor lipid accumulation. We reset the endogenous rhythm through entrainment with UVA radiation, and generated two new ultradian rhythms with periods of approximately 2.97 h and 3.8 h in the light phase and dark phase, respectively. The reset increased the window of maximum lipid accumulation from 6 h to 12 h concomitant with the onset of the ultradian rhythms. Further, the saturated fatty acid content increased approximately to 80% of total lipid content, corresponding to the peak maxima of the hydroxyl radical levels in the reset rhythm. © 2014 American Institute of Chemical Engineers.

  6. La economía y "Las uvas de la ira"

    Directory of Open Access Journals (Sweden)

    Mourão Paulo Reis

    2005-12-01

    Full Text Available Un estudiante me dijo una vez: "La economía no es verdadera". Este trabajo trata de mostrar cómo nos ayuda la economía a entender mejor nuestro mundo. Usando la muy conocida novela de Steinbeck Las uvas de la ira traté de relacionar los conceptos económicos básicos con la acción que se narra en el libro, para mostrar que la economía, o la literatura, son útiles para explicar la complejidad de la Gran Depresión, específicamente la complejidad asociada con las migraciones de trabajadores a otros estados. Este texto puede ser estimulante en los cursos de introducción, pues indica que las leyes del mercado son nociones básicas útiles, así como la información imperfecta, los mercados competitivos o la negociación colectiva.

  7. Corneal resistance to shear force after UVA-riboflavin cross-linking.

    Science.gov (United States)

    Søndergaard, Anders P; Ivarsen, Anders; Hjortdal, Jesper

    2013-07-26

    We evaluated whether UVA-riboflavin collagen cross-linking (CXL) increases transverse stromal shear moduli ex vivo, whether the shear moduli are greater in the anterior compared to the posterior stroma, and whether the shear moduli are affected by CXL. The resistance to unidirectional transverse shear of human (n = 18) and porcine (n = 42) corneas was measured in a custom engineered biaxial biomechanical setup at different hydrations. The corneas were separated into untreated, riboflavin solution-treated, and CXL-treated groups. The depth dependency of shear moduli within groups was assessed in femtosecond laser cut sheets. Dry weights were obtained for solids correction. In porcine full-thickness buttons and 300 μm anterior sheets, a significantly increased unidirectional transverse shear modulus was detected in riboflavin-treated and CXL-treated groups compared to the respective untreated groups. There was no significant difference in shear modulus between riboflavin- and CXL-treated groups. In all groups, the shear moduli were greater in the anterior sheets compared to posterior sheets. Similar results were detected in human corneas. A method for unidirectional transverse shear resistance measurement was developed. The shear moduli were greater in the anterior compared to the posterior sheets. Increase in shear moduli was observed in the riboflavin and CXL groups compared to the untreated group, indicating that the immediate effects of the riboflavin or CXL treatment may be due partly to ground substance/dextran-5-phosphate interaction.

  8. Decreased frost hardiness of Vaccinium vitis-idaea in reponse to UV-A radiation.

    Science.gov (United States)

    Taulavuori, Kari; Keränen, Johanna; Suokanerva, Hanne; Lakkala, Kaisa; Huttunen, Satu; Laine, Kari; Taulavuori, Erja

    2012-08-01

    The aim of this study was to investigate plant frost hardiness responses to ultraviolet (UV) radiation, since the few results reported are largely contradictory. It was hypothesized that functional adaptation of life forms could explain these contradictions. Dwarf shrubs and tree seedlings, representing both evergreen and deciduous forms, were tested (Vaccinium vitis-idaea, Vaccinium myrtillus, Pinus sylvestris, Betula pubescens and its red form f. rubra). The research was performed in Sodankylä, Northern Finland (67°N), with enhanced UV-B- and UV-A-radiation treatments between 2002 and 2009. Plant frost hardiness was determined using the freeze-induced electrolyte leakage method in early autumn, during the onset of the frost hardening process. Additional physiological variables (malondialdehyde, glutathione, total phenols, C and N contents) were analyzed in V. vitis-idaea to explain the possible responses. These variables did not respond significantly to UV-radiation treatments, but explained the frost hardiness well (r² = 0.678). The main finding was that frost hardiness decreased in the evergreen shrub V. vitis-idaea, particularly with enhanced UV-A radiation. No significant responses were observed with the other plants. Therefore, this study does not support the idea that enhanced UV radiation could increase plant frost hardiness. Copyright © Physiologia Plantarum 2011.

  9. Factors affecting ultraviolet-A photon emission from β-irradiated human keratinocyte cells.

    Science.gov (United States)

    Le, M; Mothersill, C E; Seymour, C B; Ahmad, S B; Armstrong, A; Rainbow, A J; McNeill, F E

    2015-08-21

    The luminescence intensity of 340±5 nm photons emitted from HaCaT (human keratinocyte) cells was investigated using a single-photon-counting system during cellular exposure to (90)Y β-particles. Multiple factors were assessed to determine their influence upon the quantity and pattern of photon emission from β-irradiated cells. Exposure of 1 x 10(4) cells/5 mL to 703 μCi resulted in maximum UVA photoemission at 44.8 x 10(3)±2.5 x 10(3) counts per second (cps) from live HaCaT cells (background: 1-5 cps); a 16-fold increase above cell-free controls. Significant biophoton emission was achieved only upon stimulation and was also dependent upon presence of cells. UVA luminescence was measured for (90)Y activities 14 to 703 μCi where a positive relationship between photoemission and (90)Y activity was observed. Irradiation of live HaCaT cells plated at various densities produced a distinct pattern of emission whereby luminescence increased up to a maximum at 1 x 10(4) cells/5 mL and thereafter decreased. However, this result was not observed in the dead cell population. Both live and dead HaCaT cells were irradiated and were found to demonstrate different rates of photon emission at low β activities (⩽400 μCi). Dead cells exhibited greater photon emission rates than live cells which may be attributable to metabolic processes taking place to modulate the photoemissive effect. The results indicate that photon emission from HaCaT cells is perturbed by external stimulation, is dependent upon the activity of radiation delivered, the density of irradiated cells, and cell viability. It is postulated that biophoton emission may be modulated by a biological or metabolic process.

  10. Assessment of the Effect of CO2 Laser Irradiation on the Reduction of Bacteria Seeded on Commercially Available Sandblasted Acid-Etched Titanium Dental Implants: An In Vitro Study.

    Science.gov (United States)

    Ferreira, Cimara Fortes; Babu, Jegdish; Migliorati, Erica Krohn Jany; Stein, Sydney; Garcia-Godoy, Franklin

    2015-01-01

    To evaluate the capability of carbon dioxide (CO₂) laser in reducing Escherichia coli on sandblasted acid-etched (SAE) titanium dental implants. SAE dental implants were contaminated with E coli, incubated in a sterile bacterial culture medium for 24 hours, and then exposed to CO₂ laser (10,600-nm wavelength) in superpulsed waves (SPW) at 1.5, 1.7, and 2 W at 100-Hz frequency and continuous wave (CW) at 1.5, 2, and 2.5 W. The presence of bacteria trapped in the implant surfaces after contamination and decontamination was verified using spectrophotometry. Scanning electron microscopy (SEM) was used to evaluate the topography of laser irradiation. After implant surface contamination was verified, implants were exposed to CO₂ laser irradiation, and bacterial growth was measured with spectrophotometry. The control implants showed the highest bacterial growth (100% growth). Implants exposed to laser showed progressive increase in the percentage of decontamination (DC%) corresponding to the higher wattage in the SPW and CW groups. The DC% were 20.4%, 49.6%, and 51.7% in the SPW group at 100 Hz, at 1.5, 1.7, and 2 W of power, respectively. In the CW group, the DC% were 34.3%, 69.9%, and 85.5% at 1.7, 2, and 2.5 W, respectively. Kruskal-Wallis statistical analysis showed a significant difference between the groups (P laser wattage increased. CO₂ laser irradiation failed to completely decontaminate the implant surfaces. SEM analysis demonstrated damage to the top of the dental implant threads at all settings studied. Thus, CO₂ laser irradiation may not be the optimal method to decontaminate implants.

  11. Functional modifications of macrophage activity after sublethal irradiation. [Toxoplasma gondii

    Energy Technology Data Exchange (ETDEWEB)

    Swartz, R.P.

    1982-01-01

    The modifications of macrophage activity following sublethal irradiation, both in vivo and in vitro, were studied using spreading and C3b-receptor-mediated ingestion assays. Nonelicited peritoneal washout cells were examined for changes in activity and selected population characteristics. The cells from irradiated mice were from a resident peritoneal population and not immigrating cells. The macrophage population showed enhanced activity early with a refractory period (24-48) when the macrophages were unresponsive to stimulation by irradiated lymphocytes. The enhanced activity was inversely dose dependent on macrophage. The lymphocytes showed a regulatory function(s) on the time post irradiation at which they were examined. Early lymphocytes exhibited the ability to enhance the activity of normal macrophages while lymphocytes removed 24 hours post irradiation could suppress the activity of already activated macrophages. The effect(s) of the various lymphocyte populations were reproduced with cell-free supernatants which was indicative of the production of lymphokines. Separation on nylon wool columns indicated that the activity resided primarily in the T-cell population of lymphocytes. In vitro irradiation indicated that stimulation of the lymphocytes is macrophage dependent. Additional work indicated that sublethally irradiated macrophages did not inhibit replication of the coccidian protozoon Toxoplasma gondii although they did show increased phagocytosis. Examination of the serum from whole body irradiated mice showed the presence of a postirradiation substance which enhanced the phagocytosis of normal macrophages. It was not present in the serum of normal mice and was not endotoxin.

  12. Development of an in vitro system for the analysis of ultraviolet radiation-induced suppression of natural killer cell activity

    Energy Technology Data Exchange (ETDEWEB)

    Hersey, Peter; Magrath, Helene (Royal Newcastle Hospital, Newcastle (Australia). Mater Misericordiae Hospital Oncology and Immunology Unit); Wilkinson, Frank (National Measurement Lab., Sydney, NSW (Australia))

    1993-02-01

    Previous studies have shown that natural killer (NK) cell activity was suppressed in volunteer subjects exposed to ultraviolet radiation (UVR) from solarium lamps. The present studies were carried out to determine the spectrum of UVR responsible for suppression of NK activity and to develop in vitro methods to analyze the effectiveness of sunscreen agents in prevention of UVR-mediated suppression of NK activity and other aspects of immune function. These studies suggest that when the greater proportion of UV-A in solar radiation and its greater penetration into skin is taken into account, UV-A may have equivalent or greater direct immunosuppressive effects than UV-B. The mechanisms of their immunosuppressive effects may, however, differ. The in vitro system described here would appear to provide a simple test system for further analysis of UVR-induced immunosuppression. (Author).

  13. Study in vitro of dental enamel irradiated with a high power diode laser operating at 960 nm: morphological analysis of post-irradiation dental surface and thermal effect analysis in pulp chamber due to laser application; Estudo in vitro do esmalte dental irradiado com laser de diodo de alta potencia em 960 nm: analise morfologica da superficie dental pos-irradiada e analise do comportamento termico na camara pulpar devido a aplicacao laser

    Energy Technology Data Exchange (ETDEWEB)

    Quinto Junior, Jose

    2001-07-01

    Objectives: This study examines the structural and thermal modifications induced in dental enamel under dye assisted diode laser irradiation. The aim of this study is to verify if this laser-assisted treatment is capable to modify the enamel surface by causing fusion of the enamel surface layer. At the same time, the pulpal temperature rise must be kept low enough in order not to cause pulpar necrosis. To achieve this target, it is necessary to determine suitable laser parameters. As is known, fusion of the enamel surface followed by re-solidification produce a more acid resistant layer. This surface treatment is being researched as a new method for caries prevention. Method and Materials: A series of fourteen identically prepared enamel samples of human teeth were irradiated with a high power diode laser operating at 960 nm and using fiber delivery. Prior to irradiation, a fine layer of cromophorous ink was applied to the enamel surface. In the first part of the experiment the best parameter for pulse duration was determined. In the second part of the experimental phase the same energy density was used but with different repetition rates. During irradiation we monitored the temperature rise in the pulpal cavity. The morphology of the treated samples was analysed under SEM. Results: The morphology of the treated samples showed a homogeneously re-solidified enamel layer. The results of the temperature analysis showed a decrease of the pulpal temperature rise with decreasing repetition rate. Conclusion: With the diode laser it is possible to cause morphological alterations of the enamel surface, which is known to increase the enamel resistance against acid attack, and still maintain the temperature rise in the pulpar chamber below damage threshold. (author)

  14. Expression of Nudix hydrolase genes in barley under UV irradiation

    Science.gov (United States)

    Tanaka, Sayuri; Sugimoto, Manabu; Kihara, Makoto

    Seed storage and cultivation should be necessary to self-supply foods when astronauts would stay and investigate during long-term space travel and habitation in the bases on the Moon and Mars. Thought the sunlight is the most importance to plants, both as the ultimate energy source and as an environmental signal regulating growth and development, UV presenting the sunlight can damage many aspects of plant processes at the physiological and DNA level. Especially UV-C, which is eliminated by the stratospheric ozone layer, is suspected to be extremely harmful and give a deadly injury to plants in space. However, the defense mechanism against UV-C irradiation damage in plant cells has not been clear. In this study, we investigated the expression of Nudix hydrolases, which defense plants from biotic / abiotic stress, in barley under UV irradiation. The genes encoding the amino acid sequences, which show homology to those of 28 kinds of Nudix hydrolases in Arabidopsis thaliana, were identified in the barley full-length cDNA library. BLAST analysis showed 14 kinds of barley genes (HvNUDX1-14), which encode the Nudix motif sequence. A phylogenetic tree showed that HvNUDX1, HvNUDX7, HvNUDX9 and HvNUDX11 belonged to the ADP-ribose pyrophosphohydrolase, ADP-sugar pyrophosphohydrolase, NAD(P)H pyrophosphohydrolase and FAD pyrophosphohydrolase subfamilies, respectively, HvNUDX3, HvNUDX6, and HvNUDX8 belonged to the Ap _{n}A pyrophosphohydrolase subfamilies, HvNUDX5 and HvNUDX14 belonged to the coenzyme A pyrophosphohydrolase subfamilies, HvNUDX12 and HvNUDX13 belonged to the Ap _{4}A pyrophosphohydrolase subfamilies. Induction of HvNUDX genes by UV-A (340nm), UV-B (312nm), and UV-C (260nm) were analyzed by quantitative RT-PCR. The results showed that HvNUDX4 was induced by UV-A and UV-B, HvNUDX6 was induced by UV-B and UV-C, and HvNUDX7 and HvNUDX14 were induced by UV-C, significantly. Our results suggest that the response of HvNUDXs to UV irradiation is different by UV

  15. Animal and human responses to UVA and UVB[UV; Skin; Eye; Carcinogenesis; Immune response

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, R.; Cridland, N.; Kowalczuk, C

    1997-12-01

    Ultraviolet radiation (UVR) comprises the most energetic region of the optical radiation spectrum and is able to induce photochemical changes in the superficial tissues of animals and people which can lead to various acute or chronic adverse health effects. The evidence concerning experimental studies of animals and, where available, volunteers of the effects of occupationally relevant wavelengths (principally UVB, 280-315 rim, and UVA, 315-400 nm) has been reviewed. Experimental studies on animals indicate that exposure to UVR elicits transient (acute) and long-lasting (chronic) effects in the skin and the eye, the severity of which increases in proportion to the exposure. Transient responses have also been investigated in human volunteers and these include adaptive changes such as immediate pigment darkening, melanogenesis and epidermal hyperplasia, and inflammatory responses such as erythema in the skin and keratitis and conjunctivitis in the eye. Irreversible, long-lasting changes also occur following exposure; these include photoageing of the skin, and the development of cataracts in the lens of the eye. Animal studies show that UVR can act either as a complete carcinogen, capable of inducing tumours when applied by itself, or as a co-carcinogen acting in combination with tumour initiators and promoters. The interaction of UVR with the immune system is complex. Exposure to UVR affects the immune system, depressing certain types of cell-mediated antigen-specific responses. Variable immunosuppressive effects have also been reported in humans. In addition, exogenous chemical sensitisers can initiate phototoxic or photoallergic responses in humans and animals; these can precede the development of more persistent idiopathic photodermatoses in which the sensitiser may be an endogenous chemical or antigen. Recommendations for further research are made. (author)

  16. Evaluation of uva camarona (Macleania rupestris Kunth A.C. Smith propagation with air layering

    Directory of Open Access Journals (Sweden)

    Santiago Durán-Casas

    2013-04-01

    Full Text Available Uva camarona (Macleania rupestris Kunth A.C. Smith belongs to the Ericaceae family and grows in páramo and subpáramo areas in Colombia, between 2,200 and 3,500 m a.s.l. This plant presents edible berries that serve as a source of food and small income for local communities. The absence of a propagation protocol for this species limits its use. This study aimed to evaluate the effectiveness of asexual propagation of M. rupestris with air layering, using indole-butyric acid (IBA as a rooting hormone at different concentrations: 0, 500, 1,000, and 2,000 mg L-1. The results showed that an exogenous application of IBA accelerated the rooting process in the layered zone, with a notable emission of first adventitious roots at 60 days from the start of the experiment. The treatments of 500 and 1,000 mg L-1 IBA had the highest number of roots per layer, being two to three times higher than those presented in the control. No significant differences were seen in root length between treatments. The treatments of 500 and 1,000 mg L-1 IBA showed a high production for the dry weights of the roots and callus, with a higher weight of callus compared to root weight. Air layering negatively affected the longitudinal growth of the branches, since their average growth rate was 1.49 cm per month, while the growth of intact branches was 2.78 cm per month. The results suggest that the best concentration for rooting was 1.200 mg L-1 IBA because it had the largest number and dry weight of roots in air-layered M. rupestris

  17. Avaliação de mosto de uva fermentado Evaluation of fermented grape must

    Directory of Open Access Journals (Sweden)

    Maria Eugênia de Oliveira Mamede

    2007-06-01

    Full Text Available O objetivo deste estudo foi determinar a concentração de compostos voláteis nos mostos de uva Chardonnay e Pinot Noir fermentados pela Pichia membranaefaciens, como também analisar as fases de crescimento da levedura durante a fermentação a 15 e 20 °C. Compostos voláteis majoritários da fermentação como: etanol, acetato de etila, acetato de isoamila, acetaldeido, 1-propanol, isobutanol e álcool isoamílico foram isolados e quantificados pelo sistema de "Purge and Trap". A fermentação conduzida a 15 °C mostrou ser mais adequada na produção de acetato de etila, com valores inferiores a 200 mg.L-1 (131,3 e 147,0 mg.L-1 nos mostos Pinot Noir e Chardonnay, respectivamente, enquanto que a 20 °C a produção foi de 286,0 e 270,0 mg.L-1 nos mostos Pinot Noir e Chardonnay, respectivamente.The aim of this study was to determine the concentration of volatile compounds in Chardonnay and Pinot Noir grape musts. The study also aims to analyze yeast growth phases during fermentation at 15 and 20 °C. Major volatile compounds of fermentation such as ethanol, ethyl acetate, isoamyl acetate, acetaldehyde, 1-propanol, 3-methyl butanol and 2-methyl butanol were isolated and quantified using the Purge and Trap system. Fermentation carried out at 15 °C was more appropriate in the production of ethyl acetate (131.3 and 147.0 mg.L-1 in the Pinot Noir and Chardonnay musts, respectively, whilst at 20 °C the production was of 286.0 and 270.0 mg.L-1 in the Pinot Noir and Chardonnay musts respectively.

  18. Impact of UV-A radiation on the performance of aphids and whiteflies and on the leaf chemistry of their host plants.

    Science.gov (United States)

    Dáder, Beatriz; Gwynn-Jones, Dylan; Moreno, Aránzazu; Winters, Ana; Fereres, Alberto

    2014-09-05

    Ultraviolet (UV) radiation directly regulates a multitude of herbivore life processes, in addition to indirectly affecting insect success via changes in plant chemistry and morphogenesis. Here we looked at plant and insect (aphid and whitefly) exposure to supplemental UV-A radiation in the glasshouse environment and investigated effects on insect population growth. Glasshouse grown peppers and eggplants were grown from seed inside cages covered by novel plastic filters, one transparent and the other opaque to UV-A radiation. At a 10-true leaf stage for peppers (53 days) and 4-true leaf stage for eggplants (34 days), plants were harvested for chemical analysis and infested by aphids and whiteflies, respectively. Clip-cages were used to introduce and monitor the insect fitness and populations of the pests studied. Insect pre-reproductive period, fecundity, fertility and intrinsic rate of natural increase were assessed. Crop growth was monitored weekly for 7 and 12 weeks throughout the crop cycle of peppers and eggplants, respectively. At the end of the insect fitness experiment, plants were harvested (68 days and 18-true leaf stage for peppers, and 104 days and 12-true leaf stage for eggplants) and leaves analysed for secondary metabolites, soluble carbohydrates, amino acids, total proteins and photosynthetic pigments. Our results demonstrate for the first time, that UV-A modulates plant chemistry with implications for insect pests. Both plant species responded directly to UV-A by producing shorter stems but this effect was only significant in pepper whilst UV-A did not affect the leaf area of either species. Importantly, in pepper, the UV-A treated plants contained higher contents of secondary metabolites, leaf soluble carbohydrates, free amino acids and total content of protein. Such changes in tissue chemistry may have indirectly promoted aphid performance. For eggplants, chlorophylls a and b, and carotenoid levels decreased with supplemental UV-A over the entire

  19. Effect of low-dose-rate irradiation on the division potential of cells in vitro. V. Human skin fibroblasts from donors with a high risk of cancer. [/sup 60/Co

    Energy Technology Data Exchange (ETDEWEB)

    Diatloff, C.; Macieira-Coelho, A.

    1979-07-01

    Skin fibroblasts from normal donors, donors with ataxia-telanglectasia or Fanconi's anemia, and from 1 cancer patient were treated with repeated ..gamma.. radiation at about 16 rads per hour. The remaining division potential of all fibroblasts, except for the Fanconi's anemia cells, was reduced to different extents by radiation. The growth potential of Fanconl's anemia cells was increased in all the irradiated cultures. The increase was 54% in the group that survived the longest. These results were identical to those obtained with fibroblasts from certain species that have a high probability of transformation.

  20. In vivo persistent pigment darkening method: proposal of a new standard product for UVA protection factor determination.

    Science.gov (United States)

    Moyal, D; Pissavini, M; Boyer, F; Perier, V; Frêlon, J H

    2007-12-01

    The European Commission (EC) has recommended assessing the level of ultraviolet A (UVA) protection afforded by sunscreen products using the in vivo persistent pigment darkening (PPD) method or other methods giving equivalent results. In this context, the reproducibility of the in vivo PPD method is of importance. To check the validity of the UVA protection factor (UVAPF) tests, the Japanese Cosmetic Industry Association (JCIA) recommends using a standard product (JCIA standard) with an expected UVAPF 3.75 (SD 1.01). However, considering the increase in UVA efficacy of the new sunscreen products available in the market, with UVAPF up to 30, it seemed useful to develop a new standard product to be used when testing products with expected UVAPF > or =10. The PPD method was used in six centres to determine the UVAPF of the two products. Reproducibility of results was also studied by testing two batches of the new product at two different times. There was no statistical difference between the six centres with regard to the JCIA standard. The ring study showed that the mean value of UVAPF (4.3) was higher than that given by JCIA (3.75). These data enable the proposal of a new acceptance range for the JCIA standard product (3.4-5.2) derived from actual results from European laboratories. Whereas this range is different from that proposed by JCIA (2.74-4.76), there is an overlapping of the values. Data on the new standard product show that reproducibility is not influenced by the batches of this product. The mean UVAPF value obtained is 12.1. An acceptance range (9.6-14.6) is proposed for the new standard. Data presented here demonstrate that if an identical protocol is used, reproducible results can be expected and that the PPD method is reproducible and reliable.

  1. Effect of ionizing radiation on platelet function in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Kalovidouris, A.E.; Papayannis, A.G. (Evangelismos Hospital, Athens (Greece))

    1981-01-01

    The effect of ionizing radiation on platelet function was investigated in vitro. Platelet-rich plasma (300x10/sup 9//l) was irradiated with doses of 1, 4, 10, 20 and 50 Gy. Platelet function tests were performed on both irradiated and control (non-irradiated) platelet samples. The platelet function tests were (1) platelet aggregation by ADP (1, 2, 4 ..mu..mol final concentration), adrenaline and collagen, (2) ADP-release from platelets, (3) clot retraction and (4) platelet factor-3 availability. It was found that roentgen irradiation of platelets in vitro did not affect these platelet function tests.

  2. Biological Effects of Millimeter-Wave Irradiation: Living Bacterial Organisms.

    Science.gov (United States)

    1984-04-01

    d’onde millimetrique sur la croissance bacterienne . Comptes Rendus Acad Sci (Paris) 281:843-846 (1975). 5. Partlow, L. M., et al. A novel in vitro...this project. This system allows simultaneous irradiation and sham irradiation of cell cultures under flowing conditions while keeping the tem... cultures of Saccharomyces cerevisiae at frequencies around 41.84 GHz. Prelim- inary results described in the next section seem to indicate a possible

  3. Influencia del estrés académico en el sistema binocular en universitarios de la UVA

    OpenAIRE

    López Gómez, Alejandra

    2017-01-01

    Objetivo: El estrés visual, tras trabajo prolongado en cerca, produce modificaciones en el sistema binocular. Esta hipótesis ha sido poco contrastada experimentalmente. El objetivo principal es medir la influencia del estrés académico en estudiantes universitarios de la UVA mediante la medida de la foria. Métodos: Se ha medido la foria en 22 estudiantes, con su corrección habitual, antes y después de un examen, mediante tres métodos: técnica de la varilla de Maddox, técnica de Von Graefe y...

  4. Modelling property changes in graphite irradiated at changing irradiation temperature

    CSIR Research Space (South Africa)

    Kok, S

    2011-01-01

    Full Text Available A new method is proposed to predict the irradiation induced property changes in nuclear; graphite, including the effect of a change in irradiation temperature. The currently used method; to account for changes in irradiation temperature, the scaled...

  5. Determinação de resveratrol em sucos de uva no Brasil Determination of resveratrol in grape juice produced in Brazil

    Directory of Open Access Journals (Sweden)

    Cláudia K. Sautter

    2005-09-01

    Full Text Available A detecção de resveratrol em vinhos vem sendo estudada mais intensamente nos últimos anos. O isômero trans-resveratrol tem reconhecidas atividades biológicas, e algumas delas são de uso terapêutico, tais como ação antiinflamatória, inibição da enzima lipoxigenase e ação anticarcinogênica in vitro. A presença do composto resveratrol (4,3',5'-trihidroxiestilbeno, em seus isômeros (trans e cis, foi determinada nos diferentes tipos de sucos de uva produzidos no Brasil. Além destes, também foram quantificados os polifenóis totais, acidez, açúcares redutores, sólidos solúveis e densidade, em conformidade com a legislação vigente. O resveratrol foi quantificado por cromatografia líquida de alta eficiência segundo SOUTO et al. [23], com adaptação da temperatura para 50° C. Foi detectada a presença de trans-resveratrol em todos os sucos analisados na concentração de 0,19mg.L-1 a 0,90mg.L-1 e o isômero cis-resveratrol foi de 0,07 a 1,59mg.L-1 .The resveratrol detection in wines has been studied more intensely in the last years. The isomeric trans-resveratrol has recognized biological activities, and some of them are therapeutic, such as anti-inflammatory action, enzyme lipoxigenase inhibition and anti-carcinogenic action in vitro. The presence of resveratrol (4,3',5'-trihydroxystilbene, trans and cis isomers, was investigated in industrial grape juices produced in Brazil. Additionally, total phenols, acidity, reducing sugars, soluble solids and specific gravity of samples were determined in accordance with law. Resveratrol was determined by high performance liquid chromatography by SOUTO et al. [23], adapted to the temperature of 50°C. Trans and cis-resveratrol were found in all the juices analyzed, tran-resveratrol in the concentration range of 0.19 to 0.90mg.L-1 and cis-resveratrol in the concentration range of 0.07 to 1.59mg.L-1.

  6. In vitro study of demineralization resistance and fluoride retention in dental enamel irradiated with Er,Cr: YSGG laser; Estudo in vitro da resistencia a desmineralizacao e da retencao de fluor em esmalte dental irradiado com laser de Er, Cr: YSGG

    Energy Technology Data Exchange (ETDEWEB)

    Ana, Patricia Aparecida da. E-mail: patriciadaana@yahoo.com.br

    2007-07-01

    This study aimed to establish irradiation conditions of Er,Cr:YSGG laser ({lambda} of 2.79 {mu}m) which could propitiate changes on human dental enamel and increase its resistance to demineralization, when associated or not with topical application of acidulated phosphate fluoride (APF). Fluences of 2,8 J/cm{sup 2}, 5,6 J/cm{sup 2} e 8,5 J/cm{sup 2} were selected; they were associated or not with previous application of a photo absorber (coal paste) and then APF was applied or not after laser irradiation. In a first step, the morphological findings, the surface temperatures, and the pupal temperatures were evaluated during laser irradiation. After that, the treated samples were submitted to a a ten-day pH-cycling model. After producing the incipient white-spots lesions, the following aspects were evaluated: the mineral loss, the loosely bound fluoride and the firmly bound fluoride. All the demineralizing and remineralizing pH-cycling solutions were evaluated with respect to their calcium (Ca), inorganic phosphorous (Pi) and fluoride (F{sup -}) concentrations. The data had their normality and homogeneity distribution statistically evaluated, and it was chosen an appropriated statistical test for each performed analysis according to the obtained results, considering 5% significant level. The fluences selected for this study created ablated surfaces; the fluences of 5.6 J/cm{sup 2} and 8.5 J/cm{sup 2} promoted increments in surface temperature above 110 deg C. The intrapupal temperature changes revealed that laser irradiation did not increase the pulpal temperatures above the critical threshold for induction of pulpitis. The coal paste did not promote any changes on surface morphology or in the intrapulpal temperature changes; however, this paste increased the surface temperatures during laser irradiation. Only laser irradiation at 8.5 J/cm{sup 2} was able to decrease the mineral loss when compared to the no-treatment group; although the association of coal paste

  7. Irradiation Creep in Graphite

    Energy Technology Data Exchange (ETDEWEB)

    Ubic, Rick; Butt, Darryl; Windes, William

    2014-03-13

    An understanding of the underlying mechanisms of irradiation creep in graphite material is required to correctly interpret experimental data, explain micromechanical modeling results, and predict whole-core behavior. This project will focus on experimental microscopic data to demonstrate the mechanism of irradiation creep. High-resolution transmission electron microscopy should be able to image both the dislocations in graphite and the irradiation-induced interstitial clusters that pin those dislocations. The team will first prepare and characterize nanoscale samples of virgin nuclear graphite in a transmission electron microscope. Additional samples will be irradiated to varying degrees at the Advanced Test Reactor (ATR) facility and similarly characterized. Researchers will record microstructures and crystal defects and suggest a mechanism for irradiation creep based on the results. In addition, the purchase of a tensile holder for a transmission electron microscope will allow, for the first time, in situ observation of creep behavior on the microstructure and crystallographic defects.

  8. ANÁLISE SENSORIAL DO SUCO INTEGRAL DE UVA ‘ISABEL’ SUBMETIDA À APLICAÇÃO DE ÁCIDO ABSCÍSICO

    OpenAIRE

    RENATA KOYAMA; ADRIANE MARINHO DE ASSIS; LILIAN YUKARI YAMAMOTO; SANDRA HELENA PRUDENCIO; SERGIO RUFFO ROBERTO

    2015-01-01

    RESUMO O suco de uva ‘Isabel’ apresenta deficiência de cor e uma alternativa é o uso de ácido abscísico para aumentar a coloração. O objetivo deste trabalho foi avaliar a aceitação do suco integral de uva ‘Isabel’ tratada com ácido abscísico (S-ABA) em diferentes concentrações e épocas, por meio da análise sensorial, obtido em duas safras consecutivas (2011 e 2012). O delineamento experimental utilizado foi em blocos completos casualizados, com quatro repetições e cin...

  9. Evaluation of temperature variation in pulp chamber after high power diode laser irradiation ({lambda}=830 nm) on dental enamel: 'in vitro' study; Avaliacao da variacao da temperatura na camara pulpar apos a irradiacao de diodo laser de alta potencia de 830 nanometros em esmalte dental: estudo 'in vitro'

    Energy Technology Data Exchange (ETDEWEB)

    Macri, Rodrigo Teixeira

    2001-07-01

    The aim of this study was to observe the variation of temperature in the pulp chamber caused by irradiation of a commercial diode laser operating in continuous wave with wavelength 830 nm over the dental enamel. In the first part of this study, two types of tooth models were tested: 3,5 mm slice and whole tooth. In the second part, we irradiated the buccal si de of the enamel in 2 primary lower incisors from cattle with Opus 10 diode laser for 10 s with power levels of 1 W and 2 W, always using an absorber. Two thermocouples were used. The first one was inserted in the dentin wall closest to the irradiation site, while the second was inserted in the middle of the pulp chamber. It was observed that the thermocouples registered different temperatures. Always, the dentin thermocouple registered higher temperatures. Considering the dentin records, the irradiation of 1 W for 10 s can be safe for the pulp. Further studies must be developed related to the correct positioning of the thermocouples inside the pulp chamber. This was a first step of using diode laser in enamel, and in this study, we concluded that the Opus 10 diode laser shown to be safe for this use, with 1 W power for 10 S. (author)

  10. Preillumination of lettuce seedlings with red light enhances the resistance of photosynthetic apparatus to UV-A.

    Science.gov (United States)

    Kreslavski, Vladimir D; Lyubimov, Valery Yu; Shirshikova, Galina N; Shmarev, Alexander N; Kosobryukhov, Anatoly A; Schmitt, Franz-Josef; Friedrich, Thomas; Allakhverdiev, Suleyman I

    2013-05-05

    Seedlings of 10-day-old lettuce (Lactuca sativa L., cultivar Berlin) were preilluminated by low intensity red light (λmax=660 nm, 10 min, 5 μmol quanta m(-2) s(-1)) and far-red light (λmax=730 nm, 10 min, 5 μmol quanta m(-2) s(-1)) to study the effect of pre-treatment on photosynthesis, photochemical activity of photosystem II (PSII), the contents of photosynthetic and UV-A-absorbing pigments (UAPs) and H2O2, as well as total and ascorbate peroxidase activities in cotyledonary leaves of seedlings exposed to UV-A. UV radiation reduced the photosynthetic rate (Pn), the activity of PSII, and the contents of Chl a and b, carotenoids and UAPs in the leaves, but increased the content of H2O2 and the total peroxidase activity. Preillumination with red light removed these effects of UV. In turn, the illumination with red light, then far-red light removed the effect of the red light. Illumination with red light alone increased the content of UAPs, as well as peroxidase activity. It is suggested that higher resistance of the lettuce photosynthetic apparatus to UV-A radiation is associated with involvement of the active form of phytochrome B, thereby increasing peroxidase activities as well as UAPs and saving preservation of photosynthetic pigment contents due to pre-illumination with red light. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Características energéticas de combustibles densificados de residuos de la uva isabella (viti labrusca L.

    Directory of Open Access Journals (Sweden)

    Andrés Felipe Rojas González

    2015-12-01

    Full Text Available Los procesos de densificación son utilizados para mejorar las características fisicoquímicas de biomasa, con la finalidad de que esta sea empleada como combustible. En este trabajo se muestran los resultados de las características energéticas que presentan los residuos provenientes del cultivo (sarmientos y producción de jugo de uva (hollejos, escobajos y semillas, al ser densificados. Para evaluar las características energéticas, tanto los residuos como las briquetas se caracterizaron respecto a su análisis próximo, análisis último y se determinó el índice de reactividad por medio de la relación materia volátil/carbono fio (MV/CF. Se encontró no fue posible densificar las semillas por la presencia de aceite en su composición, pero es el residuo de mayor HHV. También se encontró que el proceso de densificación favorece la concentración de energía y se recomienda elaborar briquetas con la mezcla de los residuos tal cual se obtienen en el cultivo y procesamiento de la uva.

  12. Wafer-scaled monolayer WO3 windows ultra-sensitive, extremely-fast and stable UV-A photodetection

    Science.gov (United States)

    Hai, Zhenyin; Akbari, Mohammad Karbalaei; Xue, Chenyang; Xu, Hongyan; Hyde, Lachlan; Zhuiykov, Serge

    2017-05-01

    The monolayer WO3-based UV-A photodetectors, fabricated by atomic layer deposition (ALD) technique at the large area of SiO2/Si wafer, have demonstrated vastly improved functional capabilities: extremely fast response time of less than 40 μs and photoresponsivity reaching of ∼0.329 A W-1. Their ultrafast photoresponse time is at least 400-fold improvement over the previous reports for any other WO3-based UV photodetectors that have ever been fabricated, and significantly faster than most of other photodetectors based on two-dimensional (2D) nanomaterials reported-to-date. Moreover, their measured long-term stability exceeds more than 200 cycles without any visible degradation. The ALD-deposited WO3 monolayer has also exhibited wider bandgap of 3.53 eV and the UV-A photodetector based on it is environmentally friendly, highly reliable, with excellent reproducibility and long-term stability. Thus, the shift to mono-layered semiconductors, which possess completely new quantum-confined effects, has the greatest potential in creating a new class of nano-materials, which in return windows new functional opportunities for various opto-electronic instruments built on semiconductor monolayer and, more importantly, can result in new strategy for fabrication highly-flexible, inexpensive and extremely-sensitive devices. This strategy also opens up the great opportunities for industrialization and commercialization of the photodetectors and other optoelectronic devices based on monolayer or few-layered 2D nanomaterials.

  13. Validation of a quantitative assay of arbutin using gas chromatography in Origanum majorana and Arctostaphylos uva-ursi extracts.

    Science.gov (United States)

    Lamien-Meda, Aline; Lukas, Brigitte; Schmiderer, Corinna; Franz, Chlodwig; Novak, Johannes

    2009-01-01

    Arbutin is a skin-whitening agent that occurs naturally in the bark and leaves of various plants. It is commonly quantified in plant extracts and skin-whitening products by HPLC. To develop an alternative gas chromatographic method for the separation and quantification of arbutin in Origanum majorana and Arctostaphylos uva-ursi extracts. N,O-Bis(trimethylsilyl)acetamide and trimethylchlorosilane were used as silylation reagents, and the gas chromatographic separation of silylated extracts and standards was performed using a DB-5 narrow bore column. GC-MS was used for the compound identification, and the quantification was carried out by GC-FID. The quantitative results were compared with those of HPLC analysis. The developed method gave a good sensitivity with linearity in the range 0.33-500 mg/mL and recovery >98%, allowing the quantification of arbutin in O. majorana and A. uva-ursi extracts. The relative standard deviations (RSD) relating to intra-day and inter-day precision were arbutin could be screened alternatively by gas chromatography.

  14. Inactivation/reactivation of antibiotic-resistant bacteria by a novel UVA/LED/TiO2 system.

    Science.gov (United States)

    Xiong, Pei; Hu, Jiangyong

    2013-09-01

    In this study, an effective photocatalytic disinfection system was established using the newly emerged high power UVA/LED lamp. Crystallizing dish coated with TiO2 was prepared by 32-times impregnation-drying processes, and served as the supporting container for water samples. This study focused on the application of this UVA/LED system for the photocatalytic disinfection of selected antibiotic-resistant bacteria, Escherichia coli ATCC 700891. The disinfection performances were studied under various light intensities and illumination modes. Results show that higher light intensity could reach more significant inactivation of E. coli ATCC 700891. With the same UV dose, log-removal of antibiotic-resistant bacteria decreased with circle time in the studied range, while increased with duty circle. A "residual disinfecting effect" was found in the following dark period for bacteria collected at different phases of photocatalytic process. Residual disinfecting effect was found not significant for bacteria with 30 min periodic illumination. While residual disinfecting effect could kill almost all bacteria after 90 min UV periodic illumination within the following 240 min dark period. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. A Focus on Quality and Safety Traits of Saccharomyces cerevisiae Isolated from Uva di Troia Grape Variety.

    Science.gov (United States)

    Petruzzi, Leonardo; Bevilacqua, Antonio; Corbo, Maria Rosaria; Speranza, Barbara; Capozzi, Vittorio; Sinigaglia, Milena

    2017-01-01

    The aim of this work was to study Saccharomyces cerevisiae strains isolated from vineyards of the autochthonous grape variety "Uva di Troia" located in different geographical areas of Apulian region (Southern Italy). Four hundred isolates were studied in relation to H2 S production, β-glucosidase activity, and pigments adsorption from grape skin. Thus, 81 isolates were selected, identified through the amplification of the interdelta region, and grouped in 19 biotypes (from I to XIX). The enological performances were assessed to determine the content of residual sugars, ethanol, glycerol, and volatile acidity, after a microfermentation in Uva di Troia must for each isolate. The ability to remove ochratoxin A (OTA) was studied as an additional tool to select promising strains. A geographical-dependent technological variability was found for glycerol and volatile acidity, suggesting that the different indigenous yeasts can have a peculiar impact on the final characteristics of the corresponding wine ("Nero di Troia"). Only 2 biotypes (VI and XVII) were able to remove OTA throughout fermentation, with the highest reduction achieved by the biotype XVII (ca. 30%). © 2016 Institute of Food Technologists®.

  16. Evaluation of erythemal UV effective irradiance from UV lamp exposure and the application in shield metal arc welding processing.

    Science.gov (United States)

    Chang, Cheng-Ping; Liu, Hung-Hsin; Peng, Chiung-Yu; Fang, Hsin-Yu; Tsao, Ta-Ho; Lan, Cheng-Hang

    2008-04-01

    Ultraviolet radiation (UVR) exposure is known to cause potential effects such as erythema in skin. For UV-induced erythema (sunburn), the action spectrum from the Commission Internationale de l'Eclairage, International Commission on Illumination (CIE) was adopted. Erythemal UV effects from UVR lamp exposure were investigated with commercial spectroradiometry devices in this research. Three kinds of portable UV germicidal lamps with broadband UVA (BB UVA, 350-400 nm), broadband UVB (BB UVB, 280-350 nm), and narrowband UVC (NB UVC, 254 nm) wavelengths served as the UVR emission sources. An action spectrum expresses the effectiveness of radiation for assessing the hazard of UVR in the erythemal action spectrum from 250-400 nm. The UV Index (UVI) is an irradiance scale computed by multiplying the CIE erythemal irradiance integral in milliwatts per square meter by 0.04 m mW. A comprehensive approach to detecting erythemal UVR magnitude was developed to monitor the effective exposure from UV lamps. The erythemal UVR measurement was established and the exposure assessment was applied to monitor erythemal UVR magnitude from shield metal arc welding (SMAW) processing. From this study, the erythemal UVR exposures were assessed and evaluated with environmental solar simulation of the UVI exposure.

  17. Cytochrome P450 4A11 expression in human keratinocytes: effects of ultraviolet irradiation.

    Science.gov (United States)

    Gonzalez, M C; Marteau, C; Franchi, J; Migliore-Samour, D

    2001-11-01

    The skin is the major interface between the body and its environment. Directly and continuously exposed to a large variety of foreign agents and stimuli such as ultraviolet radiation (UVR), cutaneous cells are active sites of intense metabolism. The cytochromes P450 (P450) are a group of enzymes that play an important part in the protective role of the skin; they are a family of microsomal membrane-bound mono-oxygenases. These haem-containing proteins catalyse the insertion of an atom of molecular oxygen into the substrate. Although generally present at low levels, a certain number of these enzymes have now been characterized in mammalian skin as constitutive or inducible isoforms. To test the effects of UVR, a source of oxidative stress, on the expression of mRNA coding for several P450 isoforms (CYP), with particular reference to the CYP2E1 and CYP4A11 isoforms, which might play a role in lipid metabolism in human keratinocytes. Human keratinocytes were cultured, irradiated and mRNA expression was analysed by gel electrophoresis after reverse transcriptase polymerase chain reactions. CYP proteins were determined from keratinocyte microsomal fractions by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and immunoperoxidase staining. Thin layer chromatography was used to detect (omega-1)- and (omega)-hydroxylation of lauric acid in the microsomal fractions. mRNAs for CYP2E1, CYP1A1 and CYP3A5 were expressed in all the keratinocyte preparations tested; however, neither CYP3A4 nor CYP3A7 were detected, either in the presence or absence of UVR treatment. CYP19Aro, CYP2C19 and CYP26 were not expressed constitutively, although some induction of CYP19Aro was seen after combined UVB and UVA irradiation. CYP4A11 mRNA was not detected in any keratinocyte preparations either under control conditions or after UVB treatment. Nevertheless, in non-irradiated keratinocyte microsomes, two protein bands were immunoreactive with anti-CYP4A11 enzyme antibodies, one of which

  18. Amarginal contribution of selected carotenoids to the supression of UV-irradiation-induced lecithin peroxidation in hexane solution

    Directory of Open Access Journals (Sweden)

    DRAGAN CVETKOVIC

    2007-03-01

    Full Text Available The aim of this work was to study the anticipated antioxidant role of four selected carotenoids in mixtures with lecithin lipoidal compounds in hexane solution, under continuous UV-irradiation in three different ranges (UV-A, UV-B and UV-C. Two carotenes (b-carotene and licopene and two xantophylls (lutein and neoxanthin were employed to control the lipid peroxidation process generated by UV-irradiation, by scavenging the involved free radicals. The results show that while carotenoids undergo a substantial, structural dependent destruction (bleaching, which is highly dependent on energy of the UV-photons, their contribution to the expected suppression of lecithin peroxidation is of marginal importance, not exceeding a maximum of 20%. The marginal antioxidant behaviour has been attributed to a highly unordered hexane solution, where the scavenging action of the carotenoids becomes less competitive.

  19. Backscattering measuring system for optimization of intravenous laser irradiation dose

    Science.gov (United States)

    Rusina, Tatyana V.; Popov, V. D.; Melnik, Ivan S.; Dets, Sergiy M.

    1996-11-01

    Intravenous laser blood irradiation as an effective method of biostimulation and physiotherapy becomes a more popular procedure. Optimal irradiation conditions for each patient are needed to be established individually. A fiber optics feedback system combined with conventional intravenous laser irradiation system was developed to control of irradiation process. The system consists of He-Ne laser, fiber optics probe and signal analyzer. Intravenous blood irradiation was performed in 7 healthy volunteers and 19 patients with different diseases. Measurements in vivo were related to in vitro blood irradiation which was performed in the same conditions with force-circulated venous blood. Comparison of temporal variations of backscattered light during all irradiation procedures has shown a strong discrepancy on optical properties of blood in patients with various health disorders since second procedure. The best cure effect was achieved when intensity of backscattered light was constant during at least five minutes. As a result, the optical irradiation does was considered to be equal 20 minutes' exposure of 3 mW He-Ne laser light at the end of fourth procedure.

  20. Bactericidal Effects of Diode Laser Irradiation on Enterococcus faecalis Using Periapical Lesion Defect Model

    OpenAIRE

    Nagayoshi, Masato; Nishihara, Tatsuji; Nakashima, Keisuke; Iwaki, Shigetsugu; Chen, Ker-Kong; TERASHITA, Masamichi; Kitamura, Chiaki

    2011-01-01

    Objective. Photodynamic therapy has been expanded for use in endodontic treatment. The aim of this study was to investigate the antimicrobial effects of diode laser irradiation on endodontic pathogens in periapical lesions using an in vitro apical lesion model. Study Design. Enterococcus faecalis in 0.5% semisolid agar with a photosensitizer was injected into apical lesion area of in vitro apical lesion model. The direct effects of irradiation with a diode laser as well as heat produced by ir...

  1. AGC-2 Irradiation Report

    Energy Technology Data Exchange (ETDEWEB)

    Rohrbaugh, David Thomas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Windes, William [Idaho National Lab. (INL), Idaho Falls, ID (United States); Swank, W. David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-06-01

    The Next Generation Nuclear Plant (NGNP) will be a helium-cooled, very high temperature reactor (VHTR) with a large graphite core. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor (HTGR) designs.[ , ] Nuclear graphite H 451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphites have been developed and are considered suitable candidates for the new NGNP reactor design. To support the design and licensing of NGNP core components within a commercial reactor, a complete properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade with a specific emphasis on data related to the life limiting effects of irradiation creep on key physical properties of the NGNP candidate graphites. Based on experience with previous graphite core components, the phenomenon of irradiation induced creep within the graphite has been shown to be critical to the total useful lifetime of graphite components. Irradiation induced creep occurs under the simultaneous application of high temperatures, neutron irradiation, and applied stresses within the graphite components. Significant internal stresses within the graphite components can result from a second phenomenon—irradiation induced dimensional change. In this case, the graphite physically changes i.e., first shrinking and then expanding with increasing neutron dose. This disparity in material volume change can induce significant internal stresses within graphite components. Irradiation induced creep relaxes these large internal stresses, thus reducing the risk of crack formation and component failure. Obviously, higher irradiation creep levels tend to relieve more internal stress, thus allowing the

  2. UvA Rescue - Team Description Paper - Infrastructure competition - Rescue Simulation League RoboCup 2014 - João Pessoa - Brazil

    NARCIS (Netherlands)

    Visser, A.

    2014-01-01

    The UvA Rescue Team has several innovative ideas to further improve the infrastructure of the RoboCup Rescue Simulation League. Those ideas range from providing USARSim an interface compatible with the RoboCup@Home Simulation, to provide the possibility to specify robots in the URDF format, to

  3. Qualidade sensorial e físico-química de uvas finas de mesa cultivadas no submédio São Francisco

    Directory of Open Access Journals (Sweden)

    Robson de Jesus Mascarenhas

    2013-06-01

    Full Text Available O objetivo deste trabalho foi avaliar uvas Vitis vinifera L. das variedades comerciais: Brasil, Benitaka, Itália e Red Globe, quanto às características físico-químicas e sensoriais. Os teores de sólidos solúveis, diâmetro e comprimento das bagas, cujos resultados apresentaram conformidade com os padrões comerciais, foram determinados. A avaliação sensorial foi realizada por meio da Análise Descritiva Quantitativa - ADQ. Foram selecionados e treinados os julgadores que, sob orientação de um líder, estabeleceram os atributos sensoriais capazes de descrever com fidedignidade as características das uvas, conforme se segue: tonalidade de cor, uniformidade de cor, aroma característico, firmeza, gosto doce, gosto amargo, gosto ácido, adstringência, sabor e qualidade global. Constatou-se que as médias obtidas nos atributos tonalidade de cor, uniformidade de cor, firmeza, sabor e qualidade global diferiram estatisticamente dentre as uvas avaliadas e, ainda, que os atributos do sabor, seguido do gosto doce e da tonalidade da cor, apresentaram as correlações mais fortes com a qualidade global, determinantes, portanto, das características sensoriais das uvas.

  4. The direct observation of a psoralen-thymine UVA induced solid-state cycloaddition reaction product by single-crystal x-ray diffractometry.

    Science.gov (United States)

    Pfluger, C E; Ostrander, R L

    1989-04-01

    Single-crystal x-ray diffraction methods have been used to directly observe and simultaneously determine the molecular structure of the UVA induced cis-syn photocycloaddition product in a partially photolyzed single crystal of a psoralen(pyrone ring side)-DNA(thymine) interaction model compound, 1'-(8-oxypsoralen)-8'(thym-1"yl)3',6'-dioxaoctane.

  5. Control of dieback, caused by Eutypa lata, in red currant (Ribes rubrum) and gooseberry (Ribes uva-crispa) in the Netherlands

    NARCIS (Netherlands)

    Wenneker, M.; Steeg, van der P.A.H.; Vink, P.; Brouwershaven, van I.R.; Raak, van M.

    2011-01-01

    Wenneker, M., Vink, P., Steeg, van der P., Brouwershaven, van I., Raak, van M., 2011. Control of dieback, caused by Eutypa lata, in red currant (Ribes rubrum) and gooseberry (Ribes uva-crispa) in the Netherlands. In: book of abstracts (p. 63) – 10th International Rubus & Ribes Symposium,

  6. Ultra-weak photon emission as a non-invasive tool for the measurement of oxidative stress induced by UVA radiation in Arabidopsis thaliana.

    Science.gov (United States)

    Rastogi, Anshu; Pospíšil, Pavel

    2013-06-05

    All living organisms emit ultra-weak photon emission as a result of oxidative processes caused by the physical or chemical stress factors. In the present study, the effect of oxidative stress induced by the exposure of the plant model Arabidopsis thaliana to ultraviolet A (UVA) radiation was studied using ultra-weak photon emission. When Arabidopsis plants and leaves were exposed to UVA radiation, two kinetically distinguished phases in the ultra-weak photon emission decay were observed: the fast decay phase (τ1=0.805±0.024 min) and slow decay phase (τ2=4.321±0.166 min). The spectral analysis of the UVA radiation-induced ultra-weak photon emission showed that the photon emission during the fast decay phase is from both blue-green and red regions of the spectrum, whereas the photon emission during the slow decay phase is solely from the blue-green region of the spectrum. These observations reveal that triplet excited carbonyls contribute to ultra-weak photon emission during both fast and slow decay phases, whereas chlorophylls participate in the ultra-weak photon emission solely during the fast decay phase. It is illustrated here that the ultra-weak photon emission serves as a non-invasive method for the monitoring of oxidative stress in plants caused by UVA radiation. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Raleio de cachos sobre o potencial enológico da uva 'Cabernet Franc' em duas safras

    Directory of Open Access Journals (Sweden)

    José Luiz Marcon Filho

    2015-12-01

    Full Text Available RESUMO: O presente trabalho teve como objetivo avaliar a maturação tecnológica e fenólica das uvas na variedade 'Cabernet Franc', submetida a diferentes níveis de raleio de cachos, de modo a estabelecer critérios que contribuam para definir o manejo mais apropriado para a obtenção de uvas destinadas à elaboração de vinhos finos, em regiões acima de 900m de altitude. Os ensaios foram conduzidos durante as safras 2009/10 e 2010/11 em um vinhedo comercial a 1,230m de altitude, localizado no município de São Joaquim, SC, coordenadas 28º 17' 39" S e 49º 55' 56" W. Foi utilizada a variedade 'Cabernet Franc', enxertada sobre 'Paulsen 1103', conduzida em espaldeira, com espaçamento de 3,0m x 1,2m e cobertura anti-granizo. Os níveis de raleio de cachos, ajustados na virada de cor "véraison", corresponderam à produção máxima, com reduções percentuais em sua produtividade em 25%, 50% e 75%. Observou-se que, em região de altitude, a prática de raleio de cachos modifica as características químicas da uva 'Cabernet Franc', aumentando o pH, reduzindo o teor de SS do mosto e polifenóis da casca. A realização do raleio de cachos, além de reduzir a produção por área, não teve um efeito compensatório na qualidade do mosto, além de não ter sido observado equilíbrio vegetativo/produtivo das plantas. A redução da carga através da prática do raleio de cachos não gerou os benefícios esperados para a cv 'Cabernet Franc', cultivada em região de altitude nas duas safras avaliadas.

  8. Tropical high-altitude Andean lakes located above the tree line attenuate UV-A radiation more strongly than typical temperate alpine lakes.

    Science.gov (United States)

    Aguilera, Ximena; Lazzaro, Xavier; Coronel, Jorge S

    2013-09-01

    Tropical high-altitude Andean lakes are physically harsh ecosystems. Located above the treeline (≥4000 m a.s.l.), they share common features with temperate alpine lakes, which impose extreme conditions on their aquatic organisms: e.g., strong winds, broad diel variations in water temperature, and intense solar ultraviolet radiation (UVR). However, because of their latitude, they differ in two major ecological characteristics: they lack ice cover during the winter and they do not present summer water column stratification. We sampled 26 tropical high-altitude Andean lakes from three regions of the Bolivian Eastern Andes Cordillera during the wet period (austral summer). We performed an ordination to better describe the typology of Andean lakes in relation to the environmental variables, and we assessed the relationships among them, focussing on the UV-A transparency (360 nm) throughout the water column. We found a positive correlation between UV-A transparency calculated as Z(1%) (the depth which reaches 1% of the surface UV-A), the lake maximum depth and Secchi transparency (r = 0.61). Z(1%) of UV-A was smaller in shallow lakes than in deep lakes, indicating that shallow lakes are less transparent to UV-A than deep lakes. We hypothesize that, compared to shallow lakes, deep lakes (maximum depth > 10 m) may have lower dissolved organic carbon (DOC) concentrations (that absorb UV radiation) due to lower temperature and reduced macrophyte cover. Based on our data, tropical high-altitude Andean lakes are less transparent to UV-A (K(d) range = 1.4-11.0 m(-1); Z(1%) depth range = 0.4-3.2 m) than typical temperate alpine lakes (1-6 m(-1), 3-45 m, respectively). Moreover, they differ in vertical profiles of UV-A, chlorophyll-a, and temperature, suggesting that they may have a distinct ecological functioning. Such peculiarities justify treating tropical high-altitude Andean lakes as a separate category of alpine lakes. Tropical high-altitude Andean lakes have been poorly

  9. In vitro photoprotective effects of Marcetia taxifolia ethanolic extract and its potential for sunscreen formulations

    Directory of Open Access Journals (Sweden)

    Sônia C.C. Costa

    Full Text Available AbstractThe species Marcetia taxifolia (A. St.-Hil. DC., Melastomataceae, which is endemic of the rupestrian fields of northeastern Brazil, contains a significant amount of flavonoids. In this work, the potential of the ethanolic extract of M. taxifolia as the active principle in a sunscreen photoprotection (UV-A and UV-B formulation was investigated. The Liquid Chromatography High Performance-Diode Array Detector quantification (quercetin, total flavonoid content, antioxidant activity through 2.2-diphenyl-1- picrylhydrazil method, photoprotective activity against UV-B and UV-A radiation in vitro (spectrophotometric method and potential for eye irritation using the methodology of the hen egg test-chorioallantoic membrane were performed in the extract. After that, the formulations were prepared using different concentrations of active ethanolic extract (5, 10, 20 and 30% and the evaluation of the sun protection factor was carried out using the same methodology used for the crude extract. The crude extract showed UV-A photoprotection and low eye irritation in the hen egg test-chorioallantoic membrane test. All formulations containing M. taxifolia extract had ≥ 6 sun protection factor. Its shows the possibility to use this extracts as a sunscreen in pharmaceutical preparations.

  10. Preferencias y disposición a pagar por uva de mesa orgánica en la región del Maule, Chile

    Directory of Open Access Journals (Sweden)

    Arcadio Alberto Cerda Urrutia

    2011-09-01

    Full Text Available El presente estudio tuvo como objetivo determinar las preferencias y disposición a pagar por consumo de uva de mesa orgánica. Específicamente, se buscó determinar la utilidad y jerarquizar los atributos más importantes que consideran los individuos al momento de la elección de uva de mesa y determinar la disposición a pagar por uva de mesa orgánica en la Región del Maule, Chile. Se aplicó una encuesta a una muestra probabilística y estratificada por niveles socioeconómico en los hogares en los principales centros urbanos de la región. Se utilizó el método de análisis conjunto a fin de determinar las preferencias de los individuos por los distintos atributos y el método de valoración contingente para determinar el monto medio de sobreprecio que una persona está dispuesta a pagar por un kilo de uva orgánica. Igualmente se calculó la disposición a pagar marginal vía el método de análisis conjunto. Se determinó que el atributo más importante a la hora de adquirir este bien es el precio, mientras que la mezcla de atributos que más tiene utilidad por orden de importancia es el sabor dulce, de producción orgánica, que no posea semillas y de piel delgada.Además, se estimó que las personas están dispuestas a pagar un sobreprecio por la uva de mesa orgánica, abriendo nuevas oportunidades de negocios para el sector frutícola.

  11. Derivation and validation of a universal vital assessment (UVA) score: a tool for predicting mortality in adult hospitalised patients in sub-Saharan Africa.

    Science.gov (United States)

    Moore, Christopher C; Hazard, Riley; Saulters, Kacie J; Ainsworth, John; Adakun, Susan A; Amir, Abdallah; Andrews, Ben; Auma, Mary; Baker, Tim; Banura, Patrick; Crump, John A; Grobusch, Martin P; Huson, Michaëla A M; Jacob, Shevin T; Jarrett, Olamide D; Kellett, John; Lakhi, Shabir; Majwala, Albert; Opio, Martin; Rubach, Matthew P; Rylance, Jamie; Michael Scheld, W; Schieffelin, John; Ssekitoleko, Richard; Wheeler, India; Barnes, Laura E

    2017-01-01

    Critical illness is a leading cause of morbidity and mortality in sub-Saharan Africa (SSA). Identifying patients with the highest risk of death could help with resource allocation and clinical decision making. Accordingly, we derived and validated a universal vital assessment (UVA) score for use in SSA. We pooled data from hospital-based cohort studies conducted in six countries in SSA spanning the years 2009-2015. We derived and internally validated a UVA score using decision trees and linear regression and compared its performance with the modified early warning score (MEWS) and the quick sepsis-related organ failure assessment (qSOFA) score. Of 5573 patients included in the analysis, 2829 (50.8%) were female, the median (IQR) age was 36 (27-49) years, 2122 (38.1%) were HIV-infected and 996 (17.3%) died in-hospital. The UVA score included points for temperature, heart and respiratory rates, systolic blood pressure, oxygen saturation, Glasgow Coma Scale score and HIV serostatus, and had an area under the receiver operating characteristic curve (AUC) of 0.77 (95% CI 0.75 to 0.79), which outperformed MEWS (AUC 0.70 (95% CI 0.67 to 0.71)) and qSOFA (AUC 0.69 (95% CI 0.67 to 0.72)). We identified predictors of in-hospital mortality irrespective of the underlying condition(s) in a large population of hospitalised patients in SSA and derived and internally validated a UVA score to assist clinicians in risk-stratifying patients for in-hospital mortality. The UVA score could help improve patient triage in resource-limited environments and serve as a standard for mortality risk in future studies.

  12. Attenuation of global ultraviolet and visible irradiance over Greece during the total solar eclipse of 29 March 2006

    Directory of Open Access Journals (Sweden)

    A. Kazantzidis

    2007-12-01

    Full Text Available The variability of ultraviolet and photosynthetically active radiation (PAR during the total solar eclipse of 29 March 2006 was examined in this study. The measurements from NILU-UV multichannel radiometers at 7 stations of the Greek UV Network were used, where the maximum eclipse percentage ranged from 73.1% to 94.8%. In addition, an extra instrument was established at a remote Greek island, Kastelorizo, which was within the Moon's umbral shadow. The reduction of irradiance at 305 and 312 nm relative to non-eclipse conditions at all sites was almost 1.5 times more than the corresponding decrease in the UVA and visible part of the spectrum and reached 98% for eclipse percentage equal to 94%. The availability of several instruments in close proximity to the path of the umbral shadow provided a challenging test for the models. The measured changes in UV and visible irradiance were compared with 1-D model calculations accounting for the limb darkening effect. The agreement between measurements and modeled values at all sites is within 3% for eclipse percentages of less than 30% and becomes worse as the eclipse progresses. The 1-D model reproduced the spectral effect of the eclipse in UVA and PAR wavelength regions within 3% for eclipse percentages up to 50%, but only the half of the observed change was captured as the eclipse progressed. At three sites, where the eclipse maximum was more than 94%, the measured irradiance at 305 nm for eclipse percentages of more than 85% decreased with slower rates than for longer wavelengths. As a result, the total ozone values, derived from the 305/320 nm ratios, apparently decreased significantly for high eclipse percentages. The effect is similar at all three sites, but the interpretation of this observation remains a challenge. Comparison results with 3-D model calculations shortly before, during and shortly after totality were performed for the first time and revealed an agreement with measurements

  13. Retina damage after exposure to UVA radiation on the early developmental stages of the Egyptian toad Bufo regularis Reuss

    Directory of Open Access Journals (Sweden)

    Alaa El-Din H. Sayed

    2016-10-01

    Full Text Available The present study was carried out to investigate the histological and histochemical changes in the retina on different developmental stages of Egyptian toad Bufo regularis. Our experiment started when tadpoles begin to feed. The adapted embryos are divided into 3 large tanks of 200 embryos each, collections of samples started from feeding age every three days. Both histological and histochemical results showed that the general architecture of the retina organ is correlated with the state of development. Therefore, it displayed different characteristic features depending on the investigated developmental stage starting from the larval stage (feeding began, stage 44 and ending with the post-metamorphic stage 66. Also, the present work aimed to study the chronic effects of UVA on the retina structure of B. regularis during development and metamorphosis for the first time.

  14. Selective Effects of Curcumin on CdSe/ZnS Quantum-dot-induced Phototoxicity Using UVA Irradiation in Normal Human Lymphocytes and Leukemia Cells

    OpenAIRE

    Goo, Soomin; Choi, Young Joo; Lee, Younghyun; Lee, Sunyeong; Chung, Hai Won

    2013-01-01

    Quantum dots (QDs) have received considerable attention due to their potential role in photosensitization during photodynamic therapy. Although QDS are attractive nanomaterials due to their novel and unique physicochemical properties, concerns about their toxicity remain. We suggest a combination strategy, CdSe/ZnS QDs together with curcumin, a natural yellow pigment from turmeric, to reduce QD-induced cytotoxicity. The aim of this study was to explore a potentially effective cancer treatment...

  15. Potentiation of cytotoxic action of cis-[PtCl2(NH3)(1M7AI)] by UVA irradiation. Mechanistic insights

    Czech Academy of Sciences Publication Activity Database

    Prachařová, J.; Intini, F. P.; Natile, G.; Kašpárková, Jana; Brabec, Viktor

    2018-01-01

    Roč. 472 (2018), s. 199-206 ISSN 0020-1693 R&D Projects: GA ČR(CZ) GA17-05302S; GA MŠk(CZ) LO1204 Institutional support: RVO:68081707 Keywords : cisplatin-dna adducts * tumor-cells * cross-links Impact factor: 2.002, year: 2016

  16. Effects of 960 nm diode laser irradiation on dental enamel in vitro: temperature and morphological analysis and evaluation of enamel demineralization; Estudo in vitro dos efeitos promovidos pelo laser de diodo em 960 nm no esmalte dental humano: analise de temperatura, analise morfologica e avaliacao da resistencia a desmineralizacao

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Ilka Tiemy

    2004-07-01

    The aim of this study is to determine the effects of diode laser irradiation on enamel demineralization. To achieve this goal appropriate photon absorbing substances for the laser radiation, safe laser parameters and adequate temperature measuring apparatus had to be determined. Next, the effects of diode laser and acidulated phosphate fluoride on enamel demineralization by calcium content analysis were evaluated with inductively coupled plasma atomic emission spectrometry (ICP-AES). In the first part of the study, five dyes consisting of vegetable coal diluted in five different liquids were analyzed and vegetable coal diluted in physiological solution was chosen for use as absorber. Methodologies to measure pulp chamber temperature were evaluated and modeling clay was chosen as fixture for the enamel samples held at body temperature. In the second part of the study, different energy density parameters (1.8 J/cm{sup 2}, 3.7 J/cm{sup 2}, 5.6 J/cm{sup 2}, 7.4 J/cm{sup 2} and 9.3 J/cm{sup 2}) exposure times (10, 15, 20, 25 e 30 seconds) and time intervals between dye application and laser irradiation (5, 30, 60, 90 e 120 seconds) were evaluated with respect to temperature changes in the pulp chamber. The enamel morphology was analyzed by scanning electron microscopy. Acid resistance was measured using seventy five enamel specimens, divided in five groups (control, fluoride, laser, laser + fluoride and fluoride + laser). The amount of calcium lost during demineralization in lactic acid was measured by ICP-AES. The results obtained in this experiment permit the conclusion that diode laser irradiation did not increase acid resistance. When associated with fluoride, the acid resistance did not differ from the results obtained with fluoride alone. (author)

  17. Effects of irradiated biodegradable polymer in endothelial cell monolayer formation

    Energy Technology Data Exchange (ETDEWEB)

    Arbeitman, Claudia R.; Grosso, Mariela F. del [CONICET – Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina); Gerencia de Investigación y Aplicaciones, TANDAR-CNEA (Argentina); Behar, Moni [Instituto de Física, UFRGS, Porto Alegre, RS (Brazil); García Bermúdez, Gerardo, E-mail: ggb@tandar.cnea.gov.ar [CONICET – Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina); Gerencia de Investigación y Aplicaciones, TANDAR-CNEA (Argentina); Escuela de Ciencia y Tecnología, UNSAM (Argentina)

    2013-11-01

    In this work we study cell adhesion, proliferation and cell morphology of endothelial cell cultured on poly-L-lactide acid (PLLA) modified by heavy ion irradiation. Thin films of PLLA samples were irradiated with sulfur (S) at energies of 75 MeV and gold (Au) at 18 MeV ion-beams. Ion beams were provided by the Tandar (Buenos Aires, Argentina) and Tandetron (Porto Alegre, Brazil) accelerators, respectively. The growth of a monolayer of bovine aortic endothelial cells (BAEC) onto unirradiated and irradiated surfaces has been studied by in vitro techniques in static culture. Cell viability and proliferation increased on modified substrates. But the results on unirradiated samples, indicate cell death (necrosis/apoptosis) with the consequent decrease in proliferation. We analyzed the correlation between irradiation parameters and cell metabolism and morphology.

  18. The Birmingham Irradiation Facility

    CERN Document Server

    Dervan, P; Hodgson, P; Marin-Reyes, H; Wilson, J

    2013-01-01

    At the end of 2012 the proton irradiation facility at the CERN PS [1] will shut down for two years. With this in mind, we have been developing a new ATLAS scanning facility at the University of Birmingham Medical Physics cyclotron. With proton beams of energy approximately 30 MeV, fluences corresponding to those of the upgraded Large Hadron Collider (HL-LHC) can be reached conveniently. The facility can be used to irradiate silicon sensors, optical components and mechanical structures (e.g. carbon fibre sandwiches) for the LHC upgrade programme. Irradiations of silicon sensors can be carried out in a temperature controlled cold box that can be scanned through the beam. The facility is described in detail along with the first tests carried out with mini (1 x 1 cm^2 ) silicon sensors.

  19. Neurite outgrowth on fluorinated polyimide film micropatterned by ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Okuyama, Y.; Sato, M.; Nagaoka, S.; Kawakami, H. E-mail: kawakami-hiroyoshi@c.metro-u.ac.jp; Suzuki, Y.; Iwaki, M

    2003-05-01

    In this study, we investigated neurite outgrowth on a fluorinated polyimide film micropatterned by ion irradiation. We used the fluorinated polyimide because of its excellent thermal and mechanical properties and biocompatibility. Rattus norvegicus chromaphin (PC12) cells were used for in vitro studies. The polyimide films were irradiated with He{sup +}, Ne{sup +} or Kr{sup +} at 1 x 10{sup 14} ions/cm{sup 2} using an ion-beam mask. The lines in the mask were 120 and 160 {mu}m wide and 120-160 {mu}m apart. PC12 cells were selectively adhered on the polyimide film micropatterned by Kr{sup +}-irradiation. However, the neurite length on the film irradiated by Kr{sup +} was shorter than that determined in the film irradiated by He{sup +}. On the other hand, neurite outgrowth on the polyimide film micropatterned by He{sup +}-irradiation was at least 100 {mu}m in length. This initial study indicated the enhanced outgrowth of PC12 cells on the fluorinated polyimide film micropatterned by ion irradiation.

  20. Photobiomodulation of wound healing via visible and infrared laser irradiation.

    Science.gov (United States)

    Solmaz, Hakan; Ulgen, Yekta; Gulsoy, Murat

    2017-05-01

    Fibroblast cells are known to be one of the key elements in wound healing process, which has been under the scope of research for decades. However, the exact mechanism of photobiomodulation on wound healing is not fully understood yet. Photobiomodulation of 635 and 809 nm laser irradiation at two different energy densities were investigated with two independent experiments; first, in vitro cell proliferation and then in vivo wound healing. L929 mouse fibroblast cell suspensions were exposed with 635 and 809 nm laser irradiations of 1 and 3 J/cm(2) energy densities at 50 mW output power separately for the investigation of photobiomodulation in vitro. Viabilities of cells were examined by means of MTT assays performed at the 24th, 48th, and 72nd hours following the laser irradiations. Following the in vitro experiments, 1 cm long cutaneous incisional skin wounds on Wistar albino rats (n = 24) were exposed with the same laser sources and doses in vivo. Wound samples were examined on 3rd, 5th, and 7th days of healing by means of mechanical tensile strength tests and histological examinations. MTT assay results showed that 635 nm laser irradiation of both energy densities after 24 h were found to be proliferative. One joule per square centimeter laser irradiation results also had positive effect on cell proliferation after 72 h. However, 809 nm laser irradiation at both energy densities had neither positive nor negative affects on cell viability. In vivo experiment results showed that, 635 nm laser irradiation of both energy densities stimulated wound healing in terms of tensile strength, whereas 809 nm laser stimulation did not cause any stimulative effect. The results of mechanical tests were compatible with the histological evaluations. In this study, it is observed that 635 nm laser irradiations of low energy densities had stimulative effects in terms of cell proliferation in vitro and mechanical strength of incisions in vivo. However, 809 nm laser

  1. Fuel or irradiation subassembly

    Science.gov (United States)

    Seim, O.S.; Hutter, E.

    1975-12-23

    A subassembly for use in a nuclear reactor is described which incorporates a loose bundle of fuel or irradiation pins enclosed within an inner tube which in turn is enclosed within an outer coolant tube and includes a locking comb consisting of a head extending through one side of the inner sleeve and a plurality of teeth which extend through the other side of the inner sleeve while engaging annular undercut portions in the bottom portion of the fuel or irradiation pins to prevent movement of the pins.

  2. [The study of the human complement cascade of proteolysis as a target of laser irradiation].

    Science.gov (United States)

    Galebskaia, L V; Andreeva, L A; Solovtsova, I L; Solov'eva, M A; Petrishchev, N N

    2009-01-01

    Samples of human blood plasma were irradiated with the laser beam (lamda=633 nm, P=13 mW, t=20 min) in vitro. In experimental and control (incubated in the dark) samples the complement hemolytic activity was measured. Laser irradiation had minor influence on the duration of lag-period and the rate of complement-dependent hemolysis via classical and alternative pathways; it also did not alter the functional activity of factor B, components C2 and C3. Nevertheless laser irradiation effect was seen in essential reduction of a bystander lysis coefficient. This new fact can elucidate some aspects of the clinical effectiveness of the blood laser irradiation.

  3. Enhanced Antimicrobial Activity Based on a Synergistic Combination of Sublethal Levels of Stresses Induced by UV-A Light and Organic Acids.

    Science.gov (United States)

    de Oliveira, Erick F; Cossu, Andrea; Tikekar, Rohan V; Nitin, Nitin

    2017-06-01

    The reduction of microbial load in food and water systems is critical for their safety and shelf life. Conventionally, physical processes such as heat or light are used for the rapid inactivation of microbes, while natural compounds such as lactic acid may be used as preservatives after the initial physical process. This study demonstrates the enhanced and rapid inactivation of bacteria based on a synergistic combination of sublethal levels of stresses induced by UV-A light and two food-grade organic acids. A reduction of 4.7 ± 0.5 log CFU/ml in Escherichia coli O157:H7 was observed using a synergistic combination of UV-A light, gallic acid (GA), and lactic acid (LA), while the individual treatments and the combination of individual organic acids with UV-A light resulted in a reduction of less than 1 log CFU/ml. Enhanced inactivation of bacteria on the surfaces of lettuce and spinach leaves was also observed based on the synergistic combination. Mechanistic investigations suggested that the treatment with a synergistic combination of GA plus LA plus UV-A (GA+LA+UV-A) resulted in significant increases in membrane permeability and intracellular thiol oxidation and affected the metabolic machinery of E. coli In addition, the antimicrobial activity of the synergistic combination of GA+LA+UV-A was effective only against metabolically active E. coli O157:H7. In summary, this study illustrates the potential of simultaneously using a combination of sublethal concentrations of natural antimicrobials and a low level of physical stress in the form of UV-A light to inactivate bacteria in water and food systems.IMPORTANCE There is a critical unmet need to improve the microbial safety of the food supply, while retaining optimal nutritional and sensory properties of food. Furthermore, there is a need to develop novel technologies that can reduce the impact of food processing operations on energy and water resources. Conventionally, physical processes such as heat and light are

  4. Bactericidal Effects of Diode Laser Irradiation on Enterococcus faecalis Using Periapical Lesion Defect Model

    Science.gov (United States)

    Nagayoshi, Masato; Nishihara, Tatsuji; Nakashima, Keisuke; Iwaki, Shigetsugu; Chen, Ker-Kong; Terashita, Masamichi; Kitamura, Chiaki

    2011-01-01

    Objective. Photodynamic therapy has been expanded for use in endodontic treatment. The aim of this study was to investigate the antimicrobial effects of diode laser irradiation on endodontic pathogens in periapical lesions using an in vitro apical lesion model. Study Design. Enterococcus faecalis in 0.5% semisolid agar with a photosensitizer was injected into apical lesion area of in vitro apical lesion model. The direct effects of irradiation with a diode laser as well as heat produced by irradiation on the viability of microorganisms in the lesions were analyzed. Results. The viability of E. faecalis was significantly reduced by the combination of a photosensitizer and laser irradiation. The temperature caused by irradiation rose, however, there were no cytotoxic effects of heat on the viability of E. faecalis. Conclusion. Our results suggest that utilization of a diode laser in combination with a photosensitizer may be useful for clinical treatment of periapical lesions. PMID:21991489

  5. NSUF Irradiated Materials Library

    Energy Technology Data Exchange (ETDEWEB)

    Cole, James Irvin [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    The Nuclear Science User Facilities has been in the process of establishing an innovative Irradiated Materials Library concept for maximizing the value of previous and on-going materials and nuclear fuels irradiation test campaigns, including utilization of real-world components retrieved from current and decommissioned reactors. When the ATR national scientific user facility was established in 2007 one of the goals of the program was to establish a library of irradiated samples for users to access and conduct research through competitively reviewed proposal process. As part of the initial effort, staff at the user facility identified legacy materials from previous programs that are still being stored in laboratories and hot-cell facilities at the INL. In addition other materials of interest were identified that are being stored outside the INL that the current owners have volunteered to enter into the library. Finally, over the course of the last several years, the ATR NSUF has irradiated more than 3500 specimens as part of NSUF competitively awarded research projects. The Logistics of managing this large inventory of highly radioactive poses unique challenges. This document will describe materials in the library, outline the policy for accessing these materials and put forth a strategy for making new additions to the library as well as establishing guidelines for minimum pedigree needed to be included in the library to limit the amount of material stored indefinitely without identified value.

  6. Childhood Head and Neck Irradiation

    Science.gov (United States)

    ... Thyroid Association ® www.thyroid.org Childhood Head & Neck Irradiation What is the thyroid gland? The thyroid gland ... Thyroid Association ® www.thyroid.org Childhood Head & Neck Irradiation Thyroid nodules (see Thyroid Nodule brochure) • Thyroid nodules ...

  7. Solar Irradiance Changes And Photobiological Effects At Earth's Surface Following Astrophysical Ionizing Radiation Events

    Science.gov (United States)

    Thomas, Brian; Neale, Patrick

    2016-01-01

    Astrophysical ionizing radiation events have been recognized as a potential threat to life on Earth for decades. Although there is some direct biological damage on the surface from redistributed radiation several studies have indicated that the greatest long term threat is from ozone depletion and subsequent heightened solar ultraviolet (UV) radiation. It is known that organisms exposed to this irradiation experience harmful effects such as sunburn and even direct damage to DNA, proteins, or other cellular structures. Simulations of the atmospheric effects of a variety of events (such as supernovae, gamma-ray bursts, and solar proton events) have been previously published, along with estimates of biological damage at Earth's surface. In the present work, we employed a radiative transfer model to expand and improve calculations of surface-level irradiance and biological impacts following an ionizing radiation event. We considered changes in surface-level UVB, UVA, and photosynthetically active radiation (visible light). Using biological weighting functions we have considered a wide range of effects, including: erythema and skin cancer in humans; inhibition of photosynthesis in the diatom Phaeodactylum sp. and dinoflagellate Prorocentrum micans inhibition of carbon fixation in Antarctic phytoplankton; inhibition of growth of oat (Avena sativa L. cv. Otana) seedlings; and cataracts. We found that past work overestimated UVB irradiance, but that relative estimates for increase in exposure to DNA damaging radiation are still similar to our improved calculations. We also found that the intensity of biologically damaging radiation varies widely with organism and specific impact considered; these results have implications for biosphere-level damage following astrophysical ionizing radiation events. When considering changes in surface-level visible light irradiance, we found that, contrary to previous assumptions, a decrease in irradiance is only present for a short time in

  8. Hepatoprotección antioxidante de la cáscara y semilla de Vitis vinifera L. (uva

    Directory of Open Access Journals (Sweden)

    Miguel Sandoval

    2008-12-01

    Full Text Available Objetivo: Determinar la capacidad hepatoprotectora antioxidante, inducida por las semillas y cáscaras de la uva Vitis vinifera L., en animales de experimentación con agresión alcohólica, mediante la prueba del TBARS (sustancias reactivas al ácido tiobarbitúrico. Diseño: Estudio experimental. Institución: Centro de Investigación de Bioquímica y Nutrición Alberto Guzmán Barrón, Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Ratones albinos, machos, adultos y cáscaras y semillas de Vitis vinifera L. (uva. Métodos: Las cáscaras y semillas de uva fueron del valle de Cañete; se las separó manualmente, se las exprimió en gasa y fueron desecadas con aire circulante, a 40º C, por 24 horas; luego, fueron trituradas, y la mezcla de cáscaras y semillas (cas-sem fue administrada ad libitum en la dieta. Se utilizó 104 ratones albinos machos adultos, separados en grupos, a los que se administró: (A cas-sem al 20%; (B alcohol al 5%; (C cas-sem con alcohol; (D silimarina 50 mg/100 g de alimento; (E silimarina con alcohol; y, (F grupo control. Bajo anestesia con éter y mediante laparotomía, se extrajo los hígados, fueron pesados y analizados por lipoperoxidación, mediante TBARS, y se evaluó la hepatomegalia, por peso a las 24, 48 y 72 horas, y a los 4, 5 y 7 días de tratamiento. Principales medidas de resultados: Lipoperoxidación hepática y hepatomegalia. Resultados: La hepatomegalia se presentó desde las 24 horas (36,68% de incremento de masa hepática, en el grupo alcohol, y fue menor en el grupo cas-sem. La prueba TBARS fue mayor en el grupo alcohol (63,91 a 67,07 nmol/g-tejido y fue menor en el grupo cas-sem (40,85 a 47,46 nmol/g-tejido; en el grupo cas-sem con alcohol, fue 43 a 63 nmol/g-tejido y la protección se observó hasta el quinto día (44 nmol/g-tejido. Conclusiones: El cas-sem administrado en la dieta, al 20% en peso, protege al tejido hepático, hasta el quinto d

  9. Inactivation of Enterococcus faecalis by TiO2-mediated UV and solar irradiation in water and wastewater: culture techniques never say the whole truth.

    Science.gov (United States)

    Venieri, Danae; Chatzisymeon, Efthalia; Gonzalo, Maria S; Rosal, Roberto; Mantzavinos, Dionissios

    2011-11-01

    In this work, the disinfection efficiency of water and secondary treated wastewater by means of UV-A, UV-C and solar irradiation in the presence or absence of TiO(2), using a reference strain of Enterococcus faecalis as faecal indicator, was evaluated. Operating parameters such as TiO(2) loading (0-1500 mg L(-1)), initial bacterial concentration (2 × 10(2)-10(8) CFU mL(-1)) and treatment time (up to 120 min) were assessed concerning their impact on disinfection. E. faecalis inactivation was monitored by the conventional culture method and real-time PCR. Regarding photocatalytic treatment, disinfection efficiency was improved by increasing TiO(2) concentration and bacterial inactivation took place in relatively short treatment times. Comparing the three disinfection methods, it was observed that UV-C irradiation yielded a better efficiency during water treatment than UV-A and solar irradiation. Furthermore, UV-A was more efficient than solar irradiation in the presence of the same loading of TiO(2). Regarding real wastewater, it was observed that only UV-C irradiation was capable of totally inactivating E. faecalis population in a short time. Screening the results obtained from both applied techniques (culture method and real-time PCR), there was a discrepancy, regarding the recorded time periods of total bacterial inactivation. Real-time PCR data revealed that longer periods are needed for 100% bacterial reduction during the treatments tested compared to the estimated time by culture method. This is probably attributed to the phenomenon of "viable but not culturable bacteria", caused by stressed conditions induced during disinfection experiments. Taking into account the contrast of results and in order to perform a thorough evaluation of disinfection techniques, conventional culture method should be accompanied by a DNA-based method. According to our findings, real-time PCR proved to be a reliable and accurate molecular tool for the identification and

  10. Análise comparativa do efeito redutor de colesterol do extrato de semente e casca de uva em ratos Wistar

    Directory of Open Access Journals (Sweden)

    Tharcia Kiara Beserra de Oliveira

    2016-12-01

    Full Text Available Os flavonóides são compostos fenólicos presentes na maioria das plantas. Têm um importante papel na prevenção e tratamento da aterosclerose, pois, atuam como agentes antiaterogênicos e hipocolesterolêmicos. Objetivou-se nessa pesquisa estudar o efeito redutor de colesterol do extrato de semente e de casca de uva (Vitis vinifera em ratos Wistar submetidos a uma dieta hipercalórica (ração acrescida de 10% de óleo vegetal no período de 20 semanas, a partir da 4ª semana de vida. A amostra, composta por 30 espécimes e distribuída entre o Grupo Controle - A (com apenas dieta hipercalórica, n=10 o Grupo Experimental Casca de Uva - B (dieta hipercalórica + extrato de casca de uva, n=10 e Grupo Experimental Semente de Uva – C (dieta hipercalórica + de extrato de semente de uva, n=10. Os resultados mostraram em média, uma redução dos níveis séricos de colesterol total de 14% e de 17,65% em relação ao grupo controle, respectivamente para os animais com dieta a base de casca e de semente de uva. Não houve diferença estatisticamente significativa na redução dos valores de colesterol entre os animais dos dois grupos, não sendo possível assim determinar qual componente da uva representa a melhor alternativa na prevenção e controle da hipercolesterolemia.Comparative analysis of reducing seed extract of cholesterol and effect bark uva in rats WistarAbstract: Flavonoids are phenolic compounds present in most plants. They play an important role in the prevention and treatment of atherosclerosis, as hypocholesterolemic and antiatherogenic act as agents. This research aimed to study and compare the cholesterol-lowering effect of seed extract and grape skin (Vitis vinifera in rats subjected to a high calorie diet (increased ration of 10% vegetable oil in the 20-week period, from the 4th week of life. The sample consisted of 30 specimens and distributed between the Control - A (with only high calorie diet, n = 10 Experimental Group

  11. DFT and TD-DFT insights, photolysis and photocatalysis investigation of three dyes with similar structure under UV irradiation with and without TiO2 as a catalyst: Effect of adsorption, pH and light intensity

    Science.gov (United States)

    Bendjabeur, Seyfeddine; Zouaghi, Razika; Zouchoune, Bachir; Sehili, Tahar

    2018-02-01

    TiO2-mediated photocatalytic degradation of three triphenylmethane dyes (basic fuchsin, acid fuchsin and Gentian violet), was investigated in aqueous suspensions in the presence and the absence of titanium dioxide P25 Degussa as photocatalyst. The photodegradation process was investigated using UV-A (365 nm) and UV-C (254 nm) light alone and UV-A in the presence of TiO2·The effects of various operational parameters were investigated such as: the effect of adsorption in the dark, the influence of pH, the influence of irradiation wavelength and the effect of light intensity. The study of the effect of various parameters reveals that the photolysis of dyes increases with the increase of light intensity, the degradation rate under UV-C (254 nm) was found better than under UV-A 365 nm. The photocatalytic degradation was found to follow the same order of adsorption. The decolorization and the degradation kinetics were found to follow the pseudo-first-order kinetics. The mineralization of dye was found to follow the same order of disappearance as the photocatalytic degradation and depended directly to its functional groups and its number of carbons. Additionally, density functional theory (DFT) was applied for calculations of both electronic structure and spectroscopic properties of the studied compounds, where the obtained results of the three dyes show that the theoretical electronic spectra and the experimental UV-visible ones are similar in shapes, positions and intensities.

  12. The offspring of irradiated parents, are they stable?

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Ruth C. [Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)]. E-mail: rcb6@le.ac.uk; Dubrova, Yuri E. [Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)

    2006-06-25

    Mutation induction in directly exposed cells is currently regarded as the main component of the genetic risk of ionising radiation for humans. However, recent studies showing that exposure to ionising radiation results in elevated mutation rates detectable in the non-irradiated progeny of exposed cells challenge the existing paradigm in radiation biology. This review describes some recent data on radiation-induced genomic instability in vitro and mainly focuses on the in vivo phenomenon of transgenerational instability, where elevated mutation rates are detected in the non-exposed offspring of irradiated parents. The possible mechanisms and implications of transgenerational instability are also discussed.

  13. Can narrow-bandwidth light from UV-A to green alter secondary plant metabolism and increase Brassica plant defenses against aphids?

    Directory of Open Access Journals (Sweden)

    Ole Rechner

    Full Text Available Light of different wavelengths is essential for plant growth and development. Short-wavelength radiation such as UV can shift the composition of flavonoids, glucosinolates, and other plant metabolites responsible for enhanced defense against certain herbivorous insects. The intensity of light-induced, metabolite-based resistance is plant- and insect species-specific and depends on herbivore feeding guild and specialization. The increasing use of light-emitting diodes (LEDs in horticultural plant production systems in protected environments enables the creation of tailor-made light scenarios for improved plant cultivation and induced defense against herbivorous insects. In this study, broccoli (Brassica oleracea var. italica plants were grown in a climate chamber under broad spectra photosynthetic active radiation (PAR and were additionally treated with the following narrow-bandwidth light generated with LEDs: UV-A (365 nm, violet (420 nm, blue (470 nm, or green (515 nm. We determined the influence of narrow-bandwidth light on broccoli plant growth, secondary plant metabolism (flavonol glycosides and glucosinolates, and plant-mediated light effects on the performance and behavior of the specialized cabbage aphid Brevicoryne brassicae. Green light increased plant height more than UV-A, violet, or blue LED treatments. Among flavonol glycosides, specific quercetin and kaempferol glycosides were increased under violet light. The concentration of 3-indolylmethyl glucosinolate in plants was increased by UV-A treatment. B. brassicae performance was not influenced by the different light qualities, but in host-choice tests, B. brassicae preferred previously blue-illuminated plants (but not UV-A-, violet-, or green-illuminated plants over control plants.

  14. Efeito da safra vitícola na composição da uva, do mosto e do vinho Isabel da Serra Ga