The effects of phototherapy and melanocytes on keratinocytes

PubMed Central

Tang, Luyan; Wu, Wenyu; Fu, Wenwen; Hu, Yao

2018-01-01

Phototherapy is widely used in the treatment of vitiligo. Previous studies have focused on the effects of ultraviolet (UV) radiation on melanocytes; however, the biological effects of phototherapy and melanocytes on keratinocytes remain to be elucidated. To investigate and assess the effects of clinically doses of broad band (BB)-UVA, narrow band (NB)-UVB and melanocytes on human keratinocytes in vitro, clinical doses of BB-UVA or NB-UVB radiation and human melanoma cell A375 co-culture were performed as stress divisors to HaCaT cells. Cell proliferation, expression of protease-activated receptor-2 (PAR-2) and nuclear factor E2-related factor 2 mRNA, lipid peroxidation and intracellular antioxidant level of keratinocytes were analyzed. It was demonstrated that UV radiation inhibited the proliferation of cells apart from following exposure to low dose (1 J/cm2) UVA. Medium dose (5 J/cm2) UVA radiation had no adverse effects on lipid peroxidation and increased antioxidant levels in HaCaT cells. Medium (200 mJ/cm2) and high (400 mJ/cm2) doses of UVB radiation induced cellular damage due to increased lipid peroxidation as indicated by levels of malondialdehyde. Furthermore, A375 co-culture treatment induced a similar effect on the lipid peroxidation of HaCaT as with low dose UVB radiation. Therefore, the results of the present study determined that clinical doses of BB-UVA and NB-UVB radiation had varying effects on proliferation and related protein levels in HaCaT cells. Co-culture with A375 had similar effects as those of low dose UVA and UVB radiation, in which the PAR-2 expression was significantly upregulated. PMID:29545869

[The 308 nm Excimer laser for the treatment of psoriasis and inflammatory skin diseases].

PubMed

Fritz, K; Salavastru, C

2018-01-01

Overall, the 308 nm Excimer laser enables not only a more effective and safer UVB therapy than classical UV phototherapy, but also targeted irradiation in higher doses with a lower cumulative load, which results in faster healing of mainly circumscribed skin changes. This also applies to therapy-resistant residual lesions which, despite systemic therapy, did not diminish. Combination therapies usually improve the result and enable the dose of UVB and systemic medication to be reduced. Excimer laser therapy can be used for an increasing number of skin diseases, especially those that respond to phototherapy or photochemotherapy.

Treatment of erosive oral lichen planus with local ultraviolet B phototherapy.

PubMed

Kassem, Riad; Yarom, Noam; Scope, Alon; Babaev, Meir; Trau, Henri; Pavlotzky, Felix

2012-05-01

Oral lichen planus (OLP) is a chronic inflammatory disease that can significantly affect the patient's quality of life. We sought to demonstrate the therapeutic efficacy of local ultraviolet (UV) B phototherapy in OLP. Patients with biopsy-confirmed erosive OLP recalcitrant to previous medical therapy were treated with the TheraLight UV 120-2 system (TheraLight Inc, Carlsbad, CA). Lesions were accessed directly using a flexible fiber guide. Local phototherapy was delivered 3 times a week, with gradual increase in UVB dose every other session. Affected oral mucosa was defined as the area showing erosions or symptomatic reticular lesions. Complete response was defined as reduction of at least 80% in the affected mucosal area, and partial response was defined as a reduction of 50% to 80% in the affected mucosal area. The primary end point was efficacy after 8 weeks of treatment. Fourteen patients were included in the study. Nine achieved complete response and 5 partial response after 8 weeks. Ten patients were continued on maintenance therapy and were able to maintain their response for another 29 weeks. None of the patients showed any serious side effects from local UVB therapy. The study was performed in a small series of patients at a single medical center. Further studies with larger patient samples are required to validate our findings. Local UVB phototherapy may be a promising treatment modality for erosive OLP. Copyright © 2011 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

Effect of narrow band ultraviolet B phototherapy as monotherapy or combination therapy for vitiligo: a meta-analysis.

PubMed

Li, Ronghua; Qiao, Meng; Wang, Xiaoyan; Zhao, Xintong; Sun, Qing

2017-01-01

The treatment of vitiligo is still one of the most difficult dermatological challenges, although there are many therapeutic options. Narrow band ultraviolet B (NB-UVB) phototherapy is considered to be a very important modality for generalized vitiligo. The aim of this study was to explore whether a combination of NB-UVB and topical agents would be superior to NB-UVB alone for treating vitiligo. We searched the electronic databases such as PUBMED, EMBASE, Cochrane Library, and Web of Science. The primary outcome was the proportion of ≥50% repigmentation (a clinical significance), and secondary outcome was the proportion of ≥75% repigmentation (an excellent response). Seven randomized controlled trials (RCTs) involving 240 patients (413 lesions) were included in this meta-analysis. The study showed no significant difference between NB-UVB combination therapy (NB-UVB and topical calcineurin inhibitor or vitamin D analogs) and NB-UVB monotherapy in the outcomes of ≥50% repigmentation and ≥75% repigmentation. However, lesions located on the face and neck had better results in ≥50% repigmentation (RR = 1.40, 95% CI 1.08-1.81) and ≥75% repigmentation (RR = 1.88, 95% CI 1.10-3.20) with NB-UVB and topical calcineurin inhibitor combination therapy vs. NB-UVB monotherapy. The meta-analysis suggested that adding neither topical calcineurin inhibitors nor topical vitamin-D3 analogs on NB-UVB can yield significantly superior outcomes than NB-UVB monotherapy for treatment of vitiligo. However, addition of topical calcineurin inhibitors to NB-UVB may increase treatment outcomes in vitiligo affecting face and neck. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Selenium, zinc, copper, Cu/Zn ratio and total antioxidant status in the serum of vitiligo patients treated by narrow-band ultraviolet-B phototherapy.

PubMed

Wacewicz, Marta; Socha, Katarzyna; Soroczyńska, Jolanta; Niczyporuk, Marek; Aleksiejczuk, Piotr; Ostrowska, Jolanta; Borawska, Maria H

2018-03-01

Vitiligo is a chronic, depigmenting skin disorder, whose pathogenesis is still unknown. Narrow band ultraviolet-B (NB-UVB) is now one of the most widely used treatment of vitiligo. It was suggested that trace elements may play a role in pathogenesis of vitiligo. The aim of this study was to estimate the concentration of selenium (Se), zinc (Zn), copper (Cu) and Cu/Zn ratio as well as total antioxidant status (TAS) in the serum of patients with vitiligo. We assessed 50 patients with vitiligo and 58 healthy controls. Serum levels of Se, Zn and Cu were determined by the atomic absorption spectrometry method, and the Cu/Zn ratio was also calculated. TAS in serum was measured spectrophotometrically. Serum concentration of Se in patients with vitiligo before and after phototherapy was significantly lower as compared to the control group. Zn level in the serum of patients decreased significantly after phototherapy. We observed higher Cu/Zn ratio (p < .05) in examined patients than in the control group and after NB-UVB. We have found decrease in TAS in the serum of vitiligo patients after NB-UVB. The current study showed some disturbances in the serum levels of trace elements and total antioxidant status in vitiligo patients.

Targeted therapy against EGFR and VEGFR using ZD6474 enhances the therapeutic potential of UV-B phototherapy in breast cancer cells.

PubMed

Sarkar, Siddik; Rajput, Shashi; Tripathi, Amit Kumar; Mandal, Mahitosh

2013-10-20

The hypoxic environment of tumor region stimulated the up regulation of growth factors responsible for angiogenesis and tumor proliferation. Thus, targeting the tumor vasculature along with the proliferation by dual tyrosine kinase inhibitor may be the efficient way of treating advanced breast cancers, which can be further enhanced by combining with radiotherapy. However, the effectiveness of radiotherapy may be severely compromised by toxicities and tumor resistance due to radiation-induced adaptive response contributing to recurrence and metastases of breast cancer. The rational of using ZD6474 is to evaluate the feasibility and efficacy of combined VEGFR2 and EGFR targeting with concurrent targeted and localized UV-B phototherapy in vitro breast cancer cells with the anticipation to cure skin lesions infiltrated with breast cancer cells. Breast cancer cells were exposed to UV-B and ZD6474 and the cell viability, apoptosis, invasion and motility studies were conducted for the combinatorial effect. Graphs and statistical analyses were performed using Graph Pad Prism 5.0. ZD6474 and UV-B decreased cell viability in breast cancers in combinatorial manner without affecting the normal human mammary epithelial cells. ZD6474 inhibited cyclin E expression and induced p53 expression when combined with UV-B. It activated stress induced mitochondrial pathway by inducing translocation of bax and cytochrome-c. The combination of ZD6474 with UV-B vs. either agent alone also more potently down-regulated the anti-apoptotic bcl-2 protein, up-regulated pro-apoptotic signaling events involving expression of bax, activation of caspase-3 and caspase-7 proteins, and induced poly (ADP-ribose) polymerase resulting in apoptosis. ZD6474 combined with UV-B inhibited invasion of breast cancer cells in vitro as compared to either single agent, indicating a potential involvement of pro-angiogenic growth factors in regulating the altered expression and reorganization of cytoskeletal proteins in combinatorial treated breast cancer cells. Involvement of combination therapy in reducing the expression of matrix metalloprotease was also observed. Collectively, our studies indicate that incorporating an anti-EGFR plus VEGFR strategy (ZD6474) with phototherapy (UV-B), an alternative approach to the ongoing conventional radiotherapy for the treatment of infiltrating metastatic breast cancer cells in the skin and for locally recurrence breast cancer than either approach alone.

Home versus outpatient ultraviolet B phototherapy for mild to severe psoriasis: pragmatic multicentre randomised controlled non-inferiority trial (PLUTO study)

PubMed Central

Buskens, Erik; van Weelden, Huib; Steegmans, Paul H A; Bruijnzeel-Koomen, Carla A F M; Sigurdsson, Vigfús

2009-01-01

Objective To determine whether ultraviolet B phototherapy at home is equally safe and equally effective as ultraviolet B phototherapy in an outpatient setting for patients with psoriasis. Design Pragmatic multicentre single blind randomised clinical trial (PLUTO study). Setting Dermatology departments of 14 hospitals in the Netherlands. Participants 196 patients with psoriasis who were clinically eligible for narrowband (TL-01) ultraviolet B phototherapy. The first 105 consecutive patients were also followed for one year after therapy. Intervention Ultraviolet B phototherapy at home using a TL-01 home phototherapy unit compared with standard narrowband ultraviolet B phototherapy in an outpatient setting. Both therapies were done in a setting reflecting routine daily practice in the Netherlands. Main outcome measures The main outcome measure was effectiveness as measured by the proportion of patients with a 50% or more reduction of the baseline psoriasis area and severity index (PASI) or self administered psoriasis area and severity index (SAPASI), called the PASI 50 and SAPASI 50 (relevant treatment effect). Another outcome of effectiveness was the percentage reduction in median scores on the PASI as well as SAPASI. Also the proportions of patients reaching the PASI 75 and SAPASI 75 (successful treatment effect), and the PASI 90 and SAPASI 90 (almost complete clearance) were calculated. Other secondary outcomes were quality of life (SF-36, psoriasis disability index), burden of treatment (questionnaire), patients’ preferences and satisfaction (questionnaire), and dosimetry and short term side effects (diary). Results 82% of the patients treated at home compared with 79% of the patients treated in an outpatient setting reached the SAPASI 50 (difference 2.8%, 95% confidence interval −8.6% to 14.2%), and 70% compared with 73% reached the PASI 50 (−2.3%, −15.7% to 11.1%). For patients treated at home the median SAPASI score decreased 82% (from 6.7 to 1.2) and the median PASI score decreased 74% (from 8.4 to 2.2), compared with 79% (from 7.0 to 1.4) and 70% (from 7.0 to 2.1) for patients treated in an outpatient setting. Treatment effect as defined by the mean decline in PASI and SAPASI scores was significant (P<0.001) and similar across groups (P>0.3). Total cumulative doses of ultraviolet B light were similar (51.5 v 46.1 J/cm2, difference 5.4, 95% confidence interval −5.2 to 16.0), and the occurrence of short term side effects did not differ. The burden of undergoing ultraviolet B phototherapy was significantly lower for patients treated at home (differences 1.23 to 3.01, all P≤0.001). Quality of life increased equally regardless of treatment, but patients treated at home more often rated their experience with the therapy as “excellent” (42%, 38/90) compared with patients treated in the outpatient department (23%, 20/88; P=0.001). Conclusion Ultraviolet B phototherapy administered at home is equally safe and equally effective, both clinically and for quality of life, as ultraviolet B phototherapy administered in an outpatient setting. Furthermore, ultraviolet B phototherapy at home resulted in a lower burden of treatment and led to greater patients’ satisfaction. Trial registration Current Controlled Trials ISRCTN83025173 and Clinicaltrials.gov NCT00150930. PMID:19423623

Home versus outpatient ultraviolet B phototherapy for mild to severe psoriasis: pragmatic multicentre randomised controlled non-inferiority trial (PLUTO study).

PubMed

Koek, Mayke B G; Buskens, Erik; van Weelden, Huib; Steegmans, Paul H A; Bruijnzeel-Koomen, Carla A F M; Sigurdsson, Vigfús

2009-05-07

To determine whether ultraviolet B phototherapy at home is equally safe and equally effective as ultraviolet B phototherapy in an outpatient setting for patients with psoriasis. Pragmatic multicentre single blind randomised clinical trial (PLUTO study). Dermatology departments of 14 hospitals in the Netherlands. 196 patients with psoriasis who were clinically eligible for narrowband (TL-01) ultraviolet B phototherapy. The first 105 consecutive patients were also followed for one year after therapy. Ultraviolet B phototherapy at home using a TL-01 home phototherapy unit compared with standard narrowband ultraviolet B phototherapy in an outpatient setting. Both therapies were done in a setting reflecting routine daily practice in the Netherlands. The main outcome measure was effectiveness as measured by the proportion of patients with a 50% or more reduction of the baseline psoriasis area and severity index (PASI) or self administered psoriasis area and severity index (SAPASI), called the PASI 50 and SAPASI 50 (relevant treatment effect). Another outcome of effectiveness was the percentage reduction in median scores on the PASI as well as SAPASI. Also the proportions of patients reaching the PASI 75 and SAPASI 75 (successful treatment effect), and the PASI 90 and SAPASI 90 (almost complete clearance) were calculated. Other secondary outcomes were quality of life (SF-36, psoriasis disability index), burden of treatment (questionnaire), patients' preferences and satisfaction (questionnaire), and dosimetry and short term side effects (diary). 82% of the patients treated at home compared with 79% of the patients treated in an outpatient setting reached the SAPASI 50 (difference 2.8%, 95% confidence interval -8.6% to 14.2%), and 70% compared with 73% reached the PASI 50 (-2.3%, -15.7% to 11.1%). For patients treated at home the median SAPASI score decreased 82% (from 6.7 to 1.2) and the median PASI score decreased 74% (from 8.4 to 2.2), compared with 79% (from 7.0 to 1.4) and 70% (from 7.0 to 2.1) for patients treated in an outpatient setting. Treatment effect as defined by the mean decline in PASI and SAPASI scores was significant (P<0.001) and similar across groups (P>0.3). Total cumulative doses of ultraviolet B light were similar (51.5 v 46.1 J/cm(2), difference 5.4, 95% confidence interval -5.2 to 16.0), and the occurrence of short term side effects did not differ. The burden of undergoing ultraviolet B phototherapy was significantly lower for patients treated at home (differences 1.23 to 3.01, all P

Skin hardening effect in patients with polymorphic light eruption: comparison of UVB hardening in hospital with a novel home UV-hardening device.

PubMed

Franken, S M; Genders, R E; de Gruijl, F R; Rustemeyer, T; Pavel, S

2013-01-01

An effective prophylactic treatment of patients with polymorphic light eruption (PLE) consists of repeated low, gradually increasing exposures to UVB radiation. This so-called UV(B) hardening induces better tolerance of the skin to sunlight. SunshowerMedical company (Amsterdam) has developed an UV (B) source that can be used during taking shower. The low UV fluence of this apparatus makes it an interesting device for UV hardening. In a group of PLE patients, we compared the effectiveness of the irradiation with SunshowerMedical at home with that of the UVB treatment in the hospital. The PLE patients were randomized for one of the treatments. The hospital treatment consisted of irradiations with broad-band UVB (Waldmann 85/UV21 lamps) twice a week during 6 weeks. The home UV-device was used each day with the maximal irradiation time of 6 min. The outcome assessment was based on the information obtained from patients' dermatological quality of life (DLQI) questionnaires, the ability of both phototherapies to reduce the provocation reaction and from the patients' evaluation of the long-term benefits of their phototherapies. Sixteen patients completed treatment with SunshowerMedical and thirteen completed treatment in hospital. Both types of phototherapy were effective. There was a highly significant improvement in DLQI with either treatment. In most cases, the hardening reduced or even completely suppressed clinical UV provocation of PLE. The patients using SunshowerMedical at home were, however, much more content with the treatment procedure than the patients visiting the dermatological units. Both treatments were equally effective in the induction of skin tolerance to sunlight in PLE patients. However, the home treatment was much better accepted than the treatment in the hospital. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.

Influence of uvA on the erythematogenic and therapeutic effects of uvB irradiation in psoriasis; photoaugmentation effects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boer, J.; Schothorst, A.A.; Suurmond, D.

1981-01-01

The effect of repeated exposure to an additive dose of long ultraviolet (uvA) radiation on the erythemogenic and therapeutic effects of middle ultraviolet (uvB) irradiation was investigated in 8 patients with psoriasis. The surface of the backs of these patients was divided into 2 parts, 1 of which received only uvB irradiation 4 times a week and the other uvA + uvB. uvB was provided by Philips TL-12 lamps and uvA by glass-filtered Philips TL-09 lamps. uvA was held constantly at 10 J/cm2, whereas uvB alone were evaluated by 4 tests during the treatment to determine the minimal erythema dosemore » (MED). Test I (at the start of the therapy) showed a photoaugmentative effect which was no longer apparent in Test III (third week). Test III showed a reversal of the ratios of the MEDs of the sites irradiated with the uvA + uvB and uvB (MED A + B/MED B). This is ascribed to the marked pigmentation which appeared after repeated irradiation with the uvA + uvB combination. Comparison showed for the improvement of the psoriasis no distinct differences between uvA + uvB irradiation and uvB alone, but the former had the cosmetic advantage of giving pleasing tan.« less

Simultaneous improvement and worsening of vitiligo lesions during the course of NB-UVB phototherapy; vitiligo may not act as one unit.

PubMed

Anbar, Tag; Abdel-Rahman, Amal; Hegazy, Rehab; El-Khayyat, Mohamed; Ragaie, Maha

2017-01-01

Re-pigmentation and stabilization are the two ultimate goals of any re-pigmenting plan designed for vitiligo management. Furthermore, whether the improvement of some vitiligo lesions could be considered a guarantee for a similar response and/or stabilization of the rest of the lesions or not, remains to be clarified. To evaluate the behavior of non-segmental vitiligo (NSV), while on narrow band-ultraviolet B (NB-UVB) phototherapy. 25 patients with stable generalized NSV were included and received NB-UVB twice weekly. For the sake of ensuring accuracy of follow up, up to four lesions were randomly chosen in each patient and regularly measured using the point counting technique. The over-all point counting technique of all included patients showed a significant reduction (18.5 ± 8.4 cm 2 to 8.2± 3.1 cm 2 ) after 6 months of therapy (p < .001). Nine patients (36%), showed mixed response in the different lesions. Improvement was documented in some lesions, while other lesions showed no response or even worsening. No significant correlations were detected between the behavior of vitiligo during NB-UVB and any of the demographic or clinical data of the patients. NB-UVB is a pillar in the management of vitiligo, however close follow-up of the patient as a whole and his lesions, by both subjective and objective measures are mandatory to detect activity as early as possible, as vitiligo at many times may not act as one unit. This early detection of activity and the subsequent change in the treatment policy may ultimately change the final outcome of treatment. © 2016 Wiley Periodicals, Inc.

The effect of platelet-rich plasma on the outcome of short-term narrowband-ultraviolet B phototherapy in the treatment of vitiligo: a pilot study.

PubMed

Ibrahim, Zeinab A; El-Ashmawy, Amal A; El-Tatawy, Rania A; Sallam, Fersan A

2016-06-01

Narrowband - ultraviolet B (NB-UVB) is an emerging, effective, and safe therapy for vitiligo, but the treatment course often requires a long duration of time which may carry a potential risk for various side effects and patients' noncompliance. To explore the effect of platelet-rich plasma (PRP) injection on the outcome of short-term NB-UVB therapy for the patients with stable vitiligo. The study included 60 stable vitiligo patients with overall symmetrical lesions. For each patient, the left side of the body was treated with NB-UVB alone (control side) while the right side was treated with NB-UVB therapy in addition to intradermal injection of PRP, every 2 weeks for 4 months. There was statistically highly significant improvement in the repigmentation in the combination group(PRP plus NB-UVB) compared with NB-UVB group. Intradermal PRP injection in combination with NB-UVB could be considered as a simple, safe, tolerable, and cheap technique for treatment of vitiligo. It shortens the duration of NB-UVB therapy and is expected to increase patient compliance. Longer follow-up is needed. © 2015 Wiley Periodicals, Inc.

The role of commercial tanning beds and ultraviolet A light in the treatment of psoriasis.

PubMed

Su, Johanna; Pearce, Daniel J; Feldman, Steven R

2005-01-01

Phototherapy is an effective, safe psoriasis treatment administered via office-based units or home devices. There is controversy over the use of commercial tanning beds; ultraviolet B (UVB) has documented efficacy although commercial beds emit largely UVA. To determine the efficacy of UVA and the role of commercial tanning beds in treating psoriasis. A literature search of UVA and commercial tanning was performed. UVA can be effective for psoriasis, but achieving the high doses required may not be practical. Tanning beds do emit UVB although amounts are variable. Because of variability in UVA and UVB output in different tanning bulbs, it is difficult to predict response rates using commercial tanning beds. UVA can be used to treat psoriasis but may not be practical. Commercial tanning beds, emitting both UVA and UVB, have a role in treating psoriasis as an alternative to office-based therapy.

Ultraviolet Phototherapy Management of Moderate-to-Severe Plaque Psoriasis: An Evidence-Based Analysis.

PubMed

2009-01-01

The purpose of this evidence based analysis was to determine the effectiveness and safety of ultraviolet phototherapy for moderate-to-severe plaque psoriasis. The specific research questions for the evidence review were as follows: What is the safety of ultraviolet phototherapy for moderate-to-severe plaque psoriasis?What is the effectiveness of ultraviolet phototherapy for moderate-to-severe plaque psoriasis? TARGET POPULATION AND CONDITION Psoriasis is a common chronic, systemic inflammatory disease affecting the skin, nails and occasionally the joints and has a lifelong waning and waxing course. It has a worldwide occurrence with a prevalence of at least 2% of the general population, making it one of the most common systemic inflammatory diseases. The immune-mediated disease has several clinical presentations with the most common (85% - 90%) being plaque psoriasis. Characteristic features of psoriasis include scaling, redness, and elevation of the skin. Patients with psoriasis may also present with a range of disabling symptoms such as pruritus (itching), pain, bleeding, or burning associated with plaque lesions and up to 30% are classified as having moderate-to-severe disease. Further, some psoriasis patients can be complex medical cases in which diabetes, inflammatory bowel disease, and hypertension are more likely to be present than in control populations and 10% also suffer from arthritis (psoriatic arthritis). The etiology of psoriasis is unknown but is thought to result from complex interactions between the environment and predisposing genes. Management of psoriasis is related to the extent of the skin involvement, although its presence on the hands, feet, face or genitalia can present challenges. Moderate-to-severe psoriasis is managed by phototherapy and a range of systemic agents including traditional immunosuppressants such as methotrexate and cyclospsorin. Treatment with modern immunosuppressant agents known as biologicals, which more specifically target the immune defects of the disease, is usually reserved for patients with contraindications and those failing or unresponsive to treatments with traditional immunosuppressants or phototherapy. Treatment plans are based on a long-term approach to managing the disease, patient's expectations, individual responses and risk of complications. The treatment goals are several fold but primarily to: 1) improve physical signs and secondary psychological effects,2) reduce inflammation and control skin shedding,3) control physical signs as long as possible, and to4) avoid factors that can aggravate the condition.Approaches are generally individualized because of the variable presentation, quality of life implications, co-existent medical conditions, and triggering factors (e.g. stress, infections and medications). Individual responses and commitments to therapy also present possible limitations. PHOTOTHERAPY: Ultraviolet phototherapy units have been licensed since February 1993 as a class 2 device in Canada. Units are available as hand held devices, hand and foot devices, full-body panel, and booth styles for institutional and home use. Units are also available with a range of ultraviolet A, broad and narrow band ultraviolet B (BB-UVB and NB-UVB) lamps. After establishing appropriate ultraviolet doses, three-times weekly treatment schedules for 20 to 25 treatments are generally needed to control symptoms. The literature search strategy employed keywords and subject headings to capture the concepts of 1) phototherapy and 2) psoriasis. The search involved runs in the following databases: Ovid MEDLINE (1996 to March Week 3 2009), OVID MEDLINE In-Process and Other Non-Indexed Citations, EMBASE (1980 to 2009 Week 13), the Wiley Cochrane Library, and the Centre for Reviews and Dissemination/International Agency for Health Technology Assessment. Parallel search strategies were developed for the remaining databases. Search results were limited to human and English-language published between January 1999 and March 31, 2009. Search alerts were generated and reviewed for relevant literature up until May 31, 2009. Inclusion CriteriaExclusion CriteriaEnglish language reports and human studiesUltraviolet phototherapy interventions for plaque-type psoriasisReports involving efficacy and/or safety outcome studiesOriginal reports with defined study methodologyStandardized measurements on outcome events such as technical success, safety, effectiveness, durability, quality of life or patient satisfactionNon-systematic reviews, letters, comments and editorialsRandomized trials involving side-to-side or half body comparisonsRandomized trials not involving ultraviolet phototherapy intervention for plaque-type psoriasisTrials involving dosing studies, pilot feasibility studies or lacking control groups A 2000 health technology evidence report on the overall management of psoriasis by The National Institute Health Research (NIHR) Health Technology Assessment Program of the UK was identified in the MAS evidence-based review. The report included 109 RCT studies published between 1966 and June 1999 involving four major treatment approaches - 51 on phototherapy, 32 on oral retinoids, 18 on cyclosporin and five on fumarates.. The absence of RCTs on methotrexate was noted as original studies with this agent had been performed prior to 1966. Of the 51 RCT studies involving phototherapy, 22 involved UVA, 21 involved UVB, five involved both UVA and UVB and three involved natural light as a source of UV. The RCT studies included comparisons of treatment schedules, ultraviolet source, addition of adjuvant therapies, and comparisons between phototherapy and topical treatment schedules. Because of heterogeneity, no synthesis or meta-analysis could be performed. Overall, the reviewers concluded that the efficacy of only five therapies could be supported from the RCT-based evidence review: photochemotherapy or phototherapy, cyclosporin, systemic retinoids, combination topical vitamin D(3) analogues (calcipotriol) and corticosteroids in combination with phototherapy and fumarates. Although there was no RCT evidence supporting methotrexate, it's efficacy for psoriasis is well known and it continues to be a treatment mainstay. The conclusion of the NIHR evidence review was that both photochemotherapy and phototherapy were effective treatments for clearing psoriasis, although their comparative effectiveness was unknown. Despite the conclusions on efficacy, a number of issues were identified in the evidence review and several areas for future research were discussed to address these limitations. Trials focusing on comparative effectiveness, either between ultraviolet sources or between classes of treatment such as methotrexate versus phototherapy, were recommended to refine treatment algorithms. The need for better assessment of cost-effectiveness of therapies to consider systemic drug costs and costs of surveillance, as well as drug efficacy, were also noted. Overall, the authors concluded that phototherapy and photochemotherapy had important roles in psoriasis management and were standard therapeutic options for psoriasis offered in dermatology practices. The MAS evidence-based review focusing on the RCT trial evidence for ultraviolet phototherapy management of moderate-to-severe plaque psoriasis was performed as an update to the NIHR 2000 systemic review on treatments for severe psoriasis. In this review, an additional 26 RCT reports examining phototherapy or photochemotherapy for psoriasis were identified. Among the studies were two RCTs comparing ultraviolet wavelength sources, five RCTs comparing different forms of phototherapy, four RCTs combining phototherapy with prior spa saline bathing, nine RCTs combining phototherapy with topical agents, two RCTs combining phototherapy with the systemic immunosuppressive agents methotrexate or alefacept, one RCT comparing phototherapy with an additional light source (the excimer laser), and one comparing a combination therapy with phototherapy and psychological intervention involving simultaneous audiotape sessions on mindfulness and stress reduction. Two trials also examined the effect of treatment setting on effectiveness of phototherapy, one on inpatient versus outpatient therapy and one on outpatient clinic versus home-based phototherapy. The conclusions of the MAS evidence-based review are outlined in Table ES1. In summary, phototherapy provides good control of clinical symptoms in the short term for patients with moderate-to-severe plaque-type psoriasis that have failed or are unresponsive to management with topical agents. However, many of the evidence gaps identified in the NIHR 2000 evidence review on psoriasis management persisted. In particular, the lack of evidence on the comparative effectiveness and/or cost-effectiveness between the major treatment options for moderate-to-severe psoriasis remained. The evidence on effectiveness and safety of longer term strategies for disease management has also not been addressed. Evidence for the safety, effectiveness, or cost-effectiveness of phototherapy delivered in various settings is emerging but is limited. In addition, because all available treatments for psoriasis - a disease with a high prevalence, chronicity, and cost - are palliative rather than curative, strategies for disease control and improvements in self-efficacy employed in other chronic disease management strategies should be investigated. (ABSTRACT TRUNCATED)

Apremilast and Narrowband Ultraviolet-B Combination Therapy for Treating Moderate-to-Severe Plaque Psoriasis.

PubMed

Bagel, Jerry; Nelson, Elise; Keegan, Brian R

2017-10-01

Combining narrowband UVB (NB-UVB) phototherapy with biologics has been shown to enhance the therapeutic response of plaque psoriasis patients. The objective of this study was to evaluate the effectiveness of apremilast combined with NB-UVB in patients with moderate to severe plaque psoriasis. This was a 12-week, open-label study of 29 patients diagnosed with moderate to severe psoriasis. Patients received apremilast 30 mg twice daily, and increasing doses of NB-UVB (310-312 nm) 3 times per week for 12 weeks. Twenty-two of 29 patients (76%) completed the 12-week apremilast and NB-UVB combination therapy; 73% (16 of 22 completers) achieved a PASI 75 response at week 12. Mean scores for PASI, VAS pain, VAS itch, DLQI, and PGA improved by 77%, 77%, 69%, 70%, and 67%, respectively, at week 12. The most commonly reported adverse events (AEs) were mild and moderate first-degree burns related to NB-UVB (n=11 [38%] patients). A second-degree NB-UVB burn was reported (likely due to an underlying photosensitivity) and was considered a serious AE. The combination of apremilast with NB-UVB was effective for the treatment of moderate to severe plaque psoriasis, without any unexpected safety signals. Apremilast combined with NB-UVB provided a high treatment response in patients with moderate to severe plaque psoriasis, and may be an option for patients to enhance a patient's initial therapeutic response.

J Drugs Dermatol. 2017;16(10):957-962.

Perspectives of the antipsoriatic heliotherapy in Poland.

PubMed

Krzyścin, J W; Narbutt, J; Lesiak, A; Jarosławski, J; Sobolewski, P S; Rajewska-Więch, B; Szkop, A; Wink, J; Czerwińska, A

2014-11-01

Statistical analysis of the daily course of exposures to TL-01 tube radiation for 93 psoriatic patients from the Medical University of Łódź during 20-day phototherapy shows that the dose of 1 J/cm(2) represents a unit of single exposure necessary for psoriasis healing. This value is converted to the antipsoriatic effective dose of 317.9 J/m(2) using the TL-01 lamp irradiance spectrum and the antipsoriatic action spectrum. It is proposed that the daily exposure of 317.9 J/m(2) serves as the standard antipsoriatic dose (SAPD) providing a link between the cabinet and the out-door exposures and it could be used for planning heliotherapy in Poland. A model is proposed to calculate ambient antipsoriatic doses for 3 h exposures around the local noon (9 am-12 am GMT) based on satellite measurements of ozone and cloud characteristics. The model constants are determined by a comparison with pertaining antipsoriatic doses measured by the Brewer spectrophotometer in central Poland. It is found that 3 h exposures to solar radiation in the period 15 May-15 September provides the mean (2005-2013) doses in the range 2.7-3.1 SAPD over Poland. Thus, heliotherapy could be treated as an alternative to the cabinet phototherapy for almost 4 months. It seems that the most effective site for antipsoriatic heliotherapy is the south/east part of Poland (the Bieszczady Mountains). The heliotherapy could be carried out in existing national health centers equipped with the standard easy-to-use biometers for on-line monitoring of UV level and controlling duration of sunbathing to avoid erythema risks. It is even possible to control the antipsoriatic heliotherapy by a patient himself, using low-cost hand-held instruments measuring UV index. Copyright © 2014 Elsevier B.V. All rights reserved.

Prospective Investigation of 25(OH)D3 Serum Concentration Following UVB Narrow Band Phototherapy in Patients with Psoriasis and Atopic Dermatitis.

PubMed

Weinhold, Annett; Obeid, Rima; Vogt, Thomas; Reichrath, Jörg

2016-03-01

Vitamin D deficiency represents a major health issue. It is a worldwide endemic and is associated with a broad variety of severe diseases. The skin is a key tissue for the human body's vitamin D endocrine system. It represents a target tissue for biologically active vitamin D metabolites. Approximately 90% of the human body's requirements of vitamin D have to be synthesised in the skin by the action of UVB-radiation. However, individual factors that influence a person's cutaneous synthesis of vitamin D are still not well understood. In our present prospective study we investigated the effect of UVB narrow band (UVBnb, 311 nm) and PUVA phototherapy on 25(OH)D3 serum concentration, in patients with psoriasis, atopic dermatitis and a few cases with other dermatoses (n=41). We found that two weeks of UVBnb treatment resulted in an increase of 25(OH)D3 serum concentration from 11.4 to 20.5 ng/ml (p<0.001), while in contrast PUVA-treatment did not significantly alter vitamin D status. These findings question the hypothesis of a relevant vitamin D metabolizing effect of UVA. Psoriasis patients showed a trend for a stronger increase in 25(OH)D3 serum levels following UVBnb compared to patients with atopic dermatitis. Patients with relatively low baseline serum 25(OH)D3 concentrations had a stronger increase in 25(OH)D3 concentrations compared to patients with relatively high 25(OH)D serum concentrations. In general patients with skin types (Fitzpatrick) I and II (median=14.3 ng/ml) had a higher baseline of 25(OH)D3 serum concentration compared to patients with skin types III (median=11.2 ng/ml) or IV-V (median=12.3 ng/ml), although these differences were not statistically significant (p=0.106). Baseline 25(OH)D3 serum concentrations were correlated with presence of genetic variants (SNPs of VDR, CYP2R1, VDBP/GC) that influence vitamin D status, and with other individual factors such as body mass index, age and gender. We also investigated the effect of phototherapy on blood pressure and a variety of laboratory parameters such as CRP, HbA1c, LDL, HDL, triglycerides and cholesterol. In conclusion, our pilot study shows that UVBnb phototherapy efficiently increases 25(OH)D3 serum concentration and reports interesting preliminary findings that have to be re-evaluated in larger follow-up studies. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

UVA-induced protection of skin through the induction of heme oxygenase-1.

PubMed

Xiang, Yuancai; Liu, Gang; Yang, Li; Zhong, Julia Li

2011-12-01

UVA (320-400 nm) and UVB (290-320 nm) are the major components of solar UV irradiation, which is associated with various pathological conditions. UVB causes direct damage to DNA of epidermal cells and is mainly responsible for erythema, immunosuppression, photoaging, and skin cancer. UVA has oxidizing properties that can cause damage or enhance UVB damaging effects on skin. On the other hand, UVA can also lead to high levels of heme oxygenase-1 (HO-1) expression of cells that can provide an antioxidant effect on skin as well as anti-inflammatory properties in mammals and rodents. Therefore, this review focuses on the potential protection of UVA wavebands for the skin immune response, instead of mechanisms that underlie UVA-induced damage. Also, the role of HO-1 in UVA-mediated protection against UVB-induced immunosuppression in skin will be summarized. Thus, this review facilitates further understanding of potential beneficial mechanisms of UVA irradiation, and using the longer UVA (UVA1, 340-400 nm) in combination with HO-1 for phototherapy and skin protection against sunlight exposure.

Combined therapy for resistant vitiligo lesions: NB-UVB, microneedling, and topical latanoprost, showed no enhanced efficacy compared to topical latanoprost and NB-UVB.

PubMed

Stanimirovic, Andrija; Kovacevic, Maja; Korobko, Igor; Šitum, Mirna; Lotti, Torello

2016-09-01

Vitiligo is depigmenting disorder of the skin and mucous membranes but despite various therapeutic options, complete and satisfactory treatment of vitiligo still remains a challenge. Therapeutic success also varies depending on the localization of lesions; hands and bony prominents are considered to be resistant to treatment. We investigated feasibility of treating resistant bilateral symmetrical vitiligo vulgaris and acrofacialis lesions with combination of narrowband UVB and topical prostaglandins (0.005% latanoprost solution) with or without Dermaroller 0.5 mm needle length-assisted microneedling. Frequency of repigmentation onset was generally low (37.8%) and pronounced repigmentation was infrequently seen (26-50% repigmentation in 20.8%, and >50% repigmentation in only 8.8% of repigmenting lesions). Our study, however, showed that latanoprost can be used in combination with NB-UVB phototherapy to induce repigmentation in some vitiligo lesions in resistant-to-treatment location, while addition of skin microneedling seems not to improve the treatment outcome and possibly needs modification. © 2016 Wiley Periodicals, Inc.

A clinical review of phototherapy for psoriasis.

PubMed

Zhang, Ping; Wu, Mei X

2018-01-01

Psoriasis is an autoimmune inflammatory skin disease. In the past several decades, phototherapy has been widely used to treat stable psoriatic lesions, including trunk, scalp, arms and legs, and partial nail psoriasis. A variety of light/lasers with different mechanisms of action have been developed for psoriasis including ultraviolet B (UVB), psoralen ultraviolet A (PUVA), pulsed dye laser (PDL), photodynamic therapy (PDT), intense pulsed light (IPL), light-emitting diodes (LED), and so on. Because light/laser each has specific therapeutic and adverse effects, it is important to adequately choose the sources and parameters in management of psoriasis with different pathogenic sites, severities, and duration of the disorder. This review aims at providing most updated clinic information to physicians about how to select light/laser sources and individual therapeutic regimens. To date, UV light is primarily for stable plaque psoriasis and PDL for topical psoriatic lesions with small area, both of which are safe and effective. On the other hand, PUVA has better curative effects than UVB for managing refractory psoriasis plaques, if its side effects can be better controlled. PDL provides optimal outcomes on nail psoriasis compared with other lasers. Although the trails of low-level light/laser therapy (LLLT) are still small, the near infrared (NIR) and visible red light with low energy show promise for treating psoriasis due to its strong penetration and encouraging photobiomodulation. IPL is rarely reported for psoriasis treatment, but PDT-IPL has been found to offer a moderate effect on nail psoriasis. In brief, various phototherapies have been used either in different combinations or as monotherapy. The modality has become a mainstay in the treatment of mild-to-moderate psoriasis without systemic adverse events in today's clinical practice.

The effect of topical piperine combined with narrowband UVB on vitiligo treatment: A clinical trial study.

PubMed

Shafiee, Anoosh; Hoormand, Mahmood; Shahidi-Dadras, Mohammad; Abadi, Alireza

2018-05-21

Vitiligo is the most common acquired hypopigmentary disease in the community. Piperine as an herbal extract derived from black pepper has strong impact on the melanocyte proliferation and adverse side effects less than synthetic drugs such as corticosteroids. For the first time, this study was aimed to evaluate the effect of topical piperine combined with narrowband ultraviolet B (NB-UVB) on vitiligo treatment. In this double-blind clinical trial, 63 patients with facial vitiligo were randomly divided into 2 groups: treated with piperine (case) and placebo (control). Also, both groups received NB-UVB phototherapy every other day for 3 months. In the case group, 10 patients have burning sensation on their skin areas (p value = .002). Also, redness of the treated areas was observed in 6 patients (p value = .028). Both side effects were temporary. Regarding repigmentation at time intervals of 1, 2, and 3 months after treatment, its level in the case group was significantly higher than the control group (p value < .001). Based on our findings, the combination therapy with NB-UVB/topical piperine has more influence on facial vitiligo than that of NB-UVB alone. It could be concluded that the simultaneous use of NB-UVB and topical piperine has a remarkable effect on treatment of vitiligo. Copyright © 2018 John Wiley & Sons, Ltd.

Endonasal phototherapy with Rhinolight for the treatment of allergic rhinitis.

PubMed

Brehmer, Detlef

2010-01-01

Allergic rhinitis, although not life threatening, significantly affects the quality of the patient's daily life. The three major steps in the treatment of the condition are avoidance of allergens, treatment of symptoms (in particular, antihistaminics and topical nasal corticosteroids) and specific immunotherapy. Avoidance of the allergen is usually not possible and symptom relief is often limited, despite the availability of a number of pharmacological options. Specific immunotherapy demands a high level of cooperation on the part of the patient for at least 3 years. Endonasal phototherapy with the Rhinolight device (Rhinolight Ltd, Szeged, Hungary) for the treatment of immunoglobulin E-mediated allergic rhinitis is a new option that utilizes the immunosuppressive effects of UV radiation. The method directs a combination of UV-B (5%), UV-A (25%) and visible light (70%) into the nasal cavity, and its effectiveness has been demonstrated in one double-blind, placebo-controlled study. The results of additional studies have been presented at various medical conferences and in abstracts. Reports in the literature confirm that phototherapy is a well-established and successful treatment of atopic dermatitis and other skin diseases.

21 CFR 880.5700 - Neonatal phototherapy unit.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Neonatal phototherapy unit. 880.5700 Section 880.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Devices § 880.5700 Neonatal phototherapy unit. (a) Identification. A neonatal phototherapy unit is a...

Development of action levels for MED/MPD skin-testing units in ultraviolet phototherapy

NASA Astrophysics Data System (ADS)

O'Connor, Una M.; O'Hare, Neil J.

2003-03-01

Ultraviolet (UV) Phototherapy is commonly used for treatment of skin diseases such as psoriasis and eczema. Treatment is carried out using UV phototherapy units, exposing all or part of the body for a certain exposure time. Prior to exposure in treatment units, an unaffected area of skin may be tested using UV skin-testing units in order to determine a suitable treatment regime. The exposure time at which barely perceptible erythema has developed is known as the Minimal Erythemal Dose (MED) for UVB therapy and Minimal Phototoxic Dose (MPD) for UVA therapy. This is used to determine the starting dose in the treatment regime. The presence of 'hotspots' and 'coldspots' in UV skin-testing units can result in inaccurate determination of MED/MPD. This could give rise to severe burns during treatment, or in a sub-optimal dose regime being used. Quality assurance protocols for UV phototherapy equipment have recently been developed and these protocols have highlighted the need for action levels for skin-testing units. An action level is a reference value, which is used to determine whether the difference in irradiance output level across a UV unit is acceptable. Current methodologies for skin-testing in Ireland have been characterised and errors introduced during testing have been estimated. Action levels have been developed based on analysis of errors and requirements of skin-testing.

Rhinophototherapy in persistent allergic rhinitis.

PubMed

Bella, Zsolt; Kiricsi, Ágnes; Viharosné, Éva Dósa-Rácz; Dallos, Attila; Perényi, Ádám; Kiss, Mária; Koreck, Andrea; Kemény, Lajos; Jóri, József; Rovó, László; Kadocsa, Edit

2017-03-01

Previous published results have revealed that Rhinolight ® intranasal phototherapy is safe and effective in intermittent allergic rhinitis. The present objective was to assess whether phototherapy is also safe and effective in persistent allergic rhinitis. Thirty-four patients with persistent allergic rhinitis were randomized into two groups; twenty-five subjects completed the study. The Rhinolight ® group was treated with a combination of UV-B, UV-A, and high-intensity visible light, while the placebo group received low-intensity visible white light intranasal phototherapy on a total of 13 occasions in 6 weeks. The assessment was based on the diary of symptoms, nasal inspiratory peak flow, quantitative smell threshold, mucociliary transport function, and ICAM-1 expression of the epithelial cells. All nasal symptom scores and nasal inspiratory peak flow measurements improved significantly in the Rhinolight ® group relative to the placebo group and this finding persisted after 4 weeks of follow-up. The smell and mucociliary functions did not change significantly in either group. The number of ICAM-1 positive cells decreased non-significantly in the Rhinolight ® group. No severe side-effects were reported during the treatment period. These results suggest that Rhinolight ® treatment is safe and effective in persistent allergic rhinitis.

Molecular response of nasal mucosa to therapeutic exposure to broad-band ultraviolet radiation

PubMed Central

Mitchell, David; Paniker, Lakshmi; Sanchez, Guillermo; Bella, Zsolt; Garaczi, Edina; Szell, Marta; Hamid, Qutayba; Kemeny, Lajos; Koreck, Andrea

2010-01-01

Abstract Ultraviolet radiation (UVR) phototherapy is a promising new treatment for inflammatory airway diseases. However, the potential carcinogenic risks associated with this treatment are not well understood. UV-specific DNA photoproducts were used as biomarkers to address this issue. Radioimmunoassay was used to quantify cyclobutane pyrimidine dimers (CPDs) and (6–4) photoproducts in DNA purified from two milieus: nasal mucosa samples from subjects exposed to intranasal phototherapy and human airway (EpiAirway™) and human skin (EpiDerm™) tissue models. Immunohistochemistry was used to detect CPD formation and persistence in human nasal biopsies and human tissue models. In subjects exposed to broadband ultraviolet radiation, DNA damage frequencies were determined prior to as well as immediately after treatment and at increasing times post-treatment. We observed significant levels of DNA damage immediately after treatment and efficient removal of the damage within a few days. No residual damage was observed in human subjects exposed to multiple UVB treatments several weeks after the last treatment. To better understand the molecular response of the nasal epithelium to DNA damage, parallel experiments were conducted in EpiAirway and EpiDerm model systems. Repair rates in these two tissues were very similar and comparable to that observed in human skin. The data suggest that the UV-induced DNA damage response of respiratory epithelia is very similar to that of the human epidermis and that nasal mucosa is able to efficiently repair UVB induced DNA damage. PMID:18671762

Influence of Li+ charge compensator ion on the energy transfer from Pr3 + to Gd3 + ions in Ca9Mg(PO4)6F2:Gd3 +, Pr3 +, Li+ phosphor

NASA Astrophysics Data System (ADS)

Tamboli, Sumedha; Dhoble, S. J.

2017-09-01

Phototherapy is a renowned treatment for curing skin diseases since ancient times. Phototherapeutic treatment for psoriasis and many other diseases require narrow band ultra violet-B (NB-UVB) light with peak intensity at 313 nm to be exposed to the affected part of body. In this paper, we report combustion synthesis of NB-UVB - 313 nm emitting Ca9Mg(PO4)6F2 phosphors doped with Gd3 +, Pr3 + and Li+ ions. The phase formation was confirmed by obtaining X-ray diffraction (XRD) pattern and morphology was studied with the Scanning electron microscopy (SEM) images. Photoluminescence (PL) emission spectra show intense narrow band emission at 313 nm under 274 nm excitation wavelengths. Emission intensity was enhanced when Ca9Mg(PO4)6F2 compound is co-doped with Pr3 + ions. Excitation spectra of Ca9Mg(PO4)6F2:Gd3 +, Pr3 + doped samples shows broad excitation in ultra violet C (UVC) region. Diffuse reflectance spectra (DRS), obtained by UV-visible spectrophotometer, measures the absorption properties of the material. By applying Kubelka Munk function on the diffuse reflectance spectra, band gap of the material is determined. PL decay curves were examined which indicates efficient energy transfer between Pr3 + and Gd3 + ions. Charge compensation effect was also studied by co-doping Li+ ion in host. Emission intensity was found to increase with the addition of charge compensator. The prepared phosphor has potential to convert UVC light into NB-UVB. The luminescence intensity of Gd3 + shows remarkable increase when it is sensitized with Pr3 +, and an addition of charge compensator in the form of Li+, show even better results. This phosphor surely has the potential to be used as phototherapy lamp phosphor.

Effect of combination of fractional CO2 laser and narrow-band ultraviolet B versus narrow-band ultraviolet B in the treatment of non-segmental vitiligo.

PubMed

El-Zawahry, Mohamed Bakr; Zaki, Naglaa Sameh; Wissa, Marian Youssry; Saleh, Marwah Adly

2017-12-01

The present study was designed to evaluate the effect of combining fractional CO 2 laser with narrow-band ultraviolet B (NB-UVB) versus NB-UVB in the treatment of non-segmental vitiligo. The study included 20 patients with non-segmental stable vitiligo. They were divided into two groups. Group I received a single session of fractional CO 2 laser therapy on the right side of the body followed by NB-UVB phototherapy twice per week for 8 weeks. Group II received a second session of fractional CO 2 laser therapy after 4 weeks from starting treatment with NB-UVB. The vitiligo lesions were assessed before treatment and after 8 weeks of treatment by VASI. At the end of the study period, the vitiligo area score index (VASI) in group I decreased insignificantly on both the right (-2.6%) and left (-16.4%) sides. In group II, VASI increased insignificantly on the right (+14.4%) and left (+2.5%) sides. Using Adobe Photoshop CS6 extended program to measure the area of vitiligo lesions, group I showed a decrease of -1.02 and -6.12% in the mean area percentage change of vitiligo lesions on the right and left sides, respectively. In group II the change was +9.84 and +9.13% on the right and left sides, respectively. In conclusion, combining fractional CO 2 laser with NB-UVB for the treatment of non-segmental vitiligo did not show any significant advantage over treatment with NB-UVB alone. Further study of this combination for longer durations in the treatment of vitiligo is recommended.

Effect of tin ions on enhancing the intensity of narrow luminescence line at 311 nm of Gd3+ ions in Li2Osbnd PbOsbnd P2O5 glass system

NASA Astrophysics Data System (ADS)

Gandhi, Y.; Rajanikanth, P.; Sundara Rao, M.; Ravi Kumar, V.; Veeraiah, N.; Piasecki, M.

2016-07-01

This study is mainly focused on enriching the UVB 311 narrow emission band of Gd3+ ions in Li2Osbnd PbOsbnd P2O5 glasses doped with 1.0 mol% of Gd2O3 and mixed with different concentrations of SnO2 (0-7.0 mol%). The emission spectra SnO2 free glasses exhibited intense narrow UVB band at 311 nm due to 6P7/2 → 8S7/2 transition of Gd3+ ions when excited at 273 nm. The intensity of this band is found to be enhanced nearly four times when the glasses are mixed with 3.0 mol% of SnO2. The reasons for this enhancement have been explored in the light of energy transfer from Sn4+ to Gd3+ ions with the help of rate equations. The declustering of Gd3+ ions (that reduce cross relaxation losses) by tin ions is also found to the other reason for such enrichment. The 311 nm radiation is an efficient in the treatment of various skin diseases and currently it is one of the most desirable and commonly utilised UVB in the construction of phototherapy devices.

Recalcitrant eosinophilic pustular folliculitis of Ofuji with palmoplantar pustulosis: dramatic response to narrowband UVB phototherapy.

PubMed

Lim, Hua Liang; Chong, Wei-Sheng

2012-08-01

Eosinophilic pustular folliculitis of Ofuji is a recalcitrant disease typified by non-infective eosinophilic spongiosis involving the infundibular region of the hair follicle. We present a case of a 49-year-old Chinese man with known palmoplantar pustulosis and acrodermatitis continua of Hallopeau which was promptly resolved with methotrexate therapy. He returned with an erythematous papulopustular eruption with coalescence to annular plaques, occurring over the face, chest and back with active palmoplantar pustulation. Histology from skin biopsy of the palmar lesion was in keeping with palmoplantar psoriasis, while biopsy of the facial and truncal lesions revealed florid perifollicular eosinophilic congregation diagnostic of eosinophilic pustular folliculitis of Ofuji. Indomethacin was initiated with partial improvement of lesions with cyclical flares. A trial of narrowband ultraviolet-B phototherapy at a frequency of thrice weekly achieved sustained clearance of both eosinophilic pustular folliculitis and palmoplantar lesions. Indomethacin was tailed down and eventually discontinued with maintenance of narrowband ultraviolet-B therapy; this achieved successful control of the disease. © 2012 John Wiley & Sons A/S.

Different susceptibility of cells of porcine skin and internal organs to ultraviolet A-induced breaking of nuclear DNA.

PubMed

Brozyna, Anna; Chwirot, Barbara W

2005-01-01

There is a continuously growing interest in medical applications of ultraviolet radiation (UV-A and long-wavelength UV-B) especially for laser surgery, phototherapy and photodiagnostics of human internal organs. UV-B and UV-A radiation is potentially mutagenic, however, there has been very little information published to date concerning the significance of possible deleterious action of such photons on cells of internal tissues. The aim of this study is to compare the sensitivities of skin cells to those of internal organs upon exposure to UV-A. To assess this sensitivity we have determined the UV-A dose-dependent frequency of nuclear DNA breaks detected with the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) technique. The materials for the study were macroscopic samples of porcine skin, colon and esophagus. The UV-A dose ranged from 0.1 to 1000 mJ/cm2, which is similar to doses received by cells in regions examined with laser-induced fluorescence or by cells surrounding areas subject to a laser ablation. To reduce the influence of DNA repair processes the tissue samples were kept at a low temperature during the irradiation and were deep frozen immediately after completing the irradiation procedure. The cells of the internal organs are much more susceptible to UV-A-induced breaking of DNA than the skin cells. The percentage fractions and the spatial distributions of the damaged cells and the characteristics of the UV-A dose dependence seem to vary by type of internal organ.

Sun exposure: what molecular photodermatology tells us about its good and bad sides.

PubMed

Krutmann, Jean; Morita, Akimichi; Chung, Jin Ho

2012-03-01

The health consequences of sun exposure have concerned mankind for more than 100 years. Recent molecular studies in photodermatology have greatly advanced our understanding of this important topic. We will illustrate this progress by focusing on the following selected topics: (i) the nature of the DNA damage-independent part of the UVB response of human skin and the role of the arylhydrocarbon receptor in cutaneous biology, (ii) the contribution of wavelengths beyond the UV spectrum to solar radiation-induced skin damage, (iii) the emerging evidence that subcutaneous fat is a target tissue for sunlight, and (iv) the most recent insight into the mode of action of phototherapy.

Comparative Study of the Gross Interpretation of Phototesting and Objective Measurement with Using a Spectrophotometer for Patients with Psoriasis and Vitiligo Treated with Narrow-band UVB

PubMed Central

Choi, Kyu-Won; Kim, Ki-Ho

2009-01-01

Background Determination of the minimal erythema dose (MED) is important for developing a phototherapy protocol and to diagnosis photosensitivity disorders. But obtaining a precise and reproducible MED is quite difficult because a phototest for erythema is based on subjective assessment. Objective The objective of our study was to compare the gross interpretation of a phototest and the objective measurement using a spectrophotometer for determining the parameters of cutaneous narrow-band UVB (NBUVB) therapy. Methods A total of 14 psoriasis and 10 vitiligo patients who receiving NBUVB phototherapy with skin types III and IV were selected for this study. To perform phototesting, ten sites on the skin of the back were vertically exposed to a series of 10 NBUVB doses among 14 doses between 340 and 1,400 mJ/cm2. We interpreted the gross findings of erythema and measured the L*a*b* values with using a spectrophotometer at each phototest spot and at the control skin. Also, we evaluate the relationship between the gross presentation and the spectrophotometric analysis by delta E for the assessment of the minimal perceptible erythema (MPE) and MED. Results For all the subjects, the MEDs were measured in the 490~1,000 mJ/cm2 range. The average of the colorimetric values for the control skin were L*: 64.8, a*: 7.9 and b*: 19.8. Among them, the L* value and MED value were shown to be inversely correlated, and as the L* value was decreased, the MED was increased. For the MPE, the delta E, which was the color difference of the normal skin and the phototest area, was within the range of 1.5~3.0 in 17 of the 21 patients, and 4 patients were within the range of 1.0~1.5. For the MED, among the 21 patients, the delta E of 17 patients was within the range of 3.0~6.0, and 4 patients were within the range of 6.0~12.0. Conclusion A spectrophotometer enables UV erythema to be assessed objectively and quantitatively, and this can compensate for the disadvantages of subjective gross interpretation when determining the MED. Delta E is a good novel and objective indicator for determining the MPE and MED. So, a spectrophotometer is a very useful instrument for developing a phototherapy protocol for psoriasis and other dermatoses and for making the diagnosis of photosensitivity disorders. PMID:20523771

Comparative Study of the Gross Interpretation of Phototesting and Objective Measurement with Using a Spectrophotometer for Patients with Psoriasis and Vitiligo Treated with Narrow-band UVB.

PubMed

Choi, Kyu-Won; Kim, Ki-Ho; Kim, Young-Hun

2009-05-01

Determination of the minimal erythema dose (MED) is important for developing a phototherapy protocol and to diagnosis photosensitivity disorders. But obtaining a precise and reproducible MED is quite difficult because a phototest for erythema is based on subjective assessment. The objective of our study was to compare the gross interpretation of a phototest and the objective measurement using a spectrophotometer for determining the parameters of cutaneous narrow-band UVB (NBUVB) therapy. A total of 14 psoriasis and 10 vitiligo patients who receiving NBUVB phototherapy with skin types III and IV were selected for this study. To perform phototesting, ten sites on the skin of the back were vertically exposed to a series of 10 NBUVB doses among 14 doses between 340 and 1,400 mJ/cm(2). We interpreted the gross findings of erythema and measured the L*a*b* values with using a spectrophotometer at each phototest spot and at the control skin. Also, we evaluate the relationship between the gross presentation and the spectrophotometric analysis by delta E for the assessment of the minimal perceptible erythema (MPE) and MED. For all the subjects, the MEDs were measured in the 490~1,000 mJ/cm(2) range. The average of the colorimetric values for the control skin were L*: 64.8, a*: 7.9 and b*: 19.8. Among them, the L* value and MED value were shown to be inversely correlated, and as the L* value was decreased, the MED was increased. For the MPE, the delta E, which was the color difference of the normal skin and the phototest area, was within the range of 1.5~3.0 in 17 of the 21 patients, and 4 patients were within the range of 1.0~1.5. For the MED, among the 21 patients, the delta E of 17 patients was within the range of 3.0~6.0, and 4 patients were within the range of 6.0~12.0. A spectrophotometer enables UV erythema to be assessed objectively and quantitatively, and this can compensate for the disadvantages of subjective gross interpretation when determining the MED. Delta E is a good novel and objective indicator for determining the MPE and MED. So, a spectrophotometer is a very useful instrument for developing a phototherapy protocol for psoriasis and other dermatoses and for making the diagnosis of photosensitivity disorders.

Quality of Life of Psoriasis Patients before and after Balneo - or Balneophototherapy

PubMed Central

Calza, Anna; Di Pietro, Cristina; Sampogna, Francesca; Abeni, Damiano

2009-01-01

Purpose An observational prospective study was conducted to study the effects of hypotonic spa-water baths and narrowband ultraviolet B therapy given alone or in combination for treatment of moderate-severe psoriasis. Materials and Methods Two treatments were analysed: 2 weeks of balneotherapy followed by ultraviolet-B (UVB) 311-nm phototherapy (BPT) or 2 weeks of daily bath treatments of Comano water alone (BT). One hundred and eleven adult patients with moderate to severe chronic plaque psoriasis were enrolled. Quality of life (QoL) questionnaires {36-item Short Form of the Medical Outcomes Study questionnaire (SF-36) and Skindex-29} were administered at baseline and 2 months from the end of therapy. The self-administered Psoriasis Area Severity Index (SAPASI), and the General Health Questionnaire (GHQ)-12 (to assess clinical severity and psychological distress, respectively) were also recorded at the same time-periods. Results SAPASI was significantly reduced from 15.2 to 8.7 in BPT group and 11.6 to 7.8 in BT. A decrease of greater than 50% after therapy in SAPASI_50 score was reached by 42% and 37% of patients in the BPT and BT groups, respectively. At follow-up, both groups had better scores on all SF-36 scales (with statistically significant improvement in social functioning and mental health in the BPT group) and in all Skindex-29 scales. A statistically significant reduction of GHQ-12 positive cases was observed in the BPT group. Conclusion Comano spa-water alone or in combination with phototherapy had beneficial therapeutic effects on patients with psoriasis. Although our observational study design prevents us from making meaningful comparisons between the 2 interventions, the combination of balneo and phototherapy seems to improve QoL and lessen clinical severity, and reduced the proportion of GHQ-12 positive cases. PMID:19430554

[Effect of ultraviolet irradiation through glass on the level of 25-hydroxy vitamin D and bone metabolism in rats].

PubMed

Wu, Wei; Wang, Shu-Rong; Zhang, Wei

2009-02-01

Some research has shown that there is a dose-dependent relationship between ultraviolet B (UVB) and serum levels of 25-hydroxy vitamin D[25-(OH)D]\\. Vitamin D is correlated with bone metabolism. This study aimed to explore the effect of UVB irradiation through glass on serum levels of 25-(OH)D and bone metabolism in rats. Wistar rats were fed with vitamin D deficient diet and randomly divided into three groups: no UVB exposure, direct UVB exposure (160 min/d) and indirect UVB exposure (through glass) (160 min/d). By 21 days after exposure, bone mineral density (BMD) and serum levels of 25-(OH)D, parathyroid hormone (PTH), osteocalcin (OC), bone alkaline phosphatase (BALP) and carboxyterminal cross-linked telopeptide of type I collagen (ICTP) were measured. BMD (0.036+/-0.002 g/cm2) in the indirect UVB exposure group was significantly higher than that in the no UVB exposure group (0.029+/-0.002 g/cm2) (<0.01). Serum ICTP level in the indirect UVB exposure group was significantly lower than that in the no UVB exposure group (0.181+/-0.067 microg/L vs 0.194+/-0.066 microg/L; <0.01). Serum levels of PTH, 25-(OH)D, BALP and OC in the indirect UVB exposure group were not significantly different from those in the no UVB exposure group. Compared with the direct UVB exposure group, serum levels of OC (0.559+/-0.067 ng/mL vs 0.278+/-0.067 ng/mL; <0.05) and PTH (0.181+/-0.067 microg/L vs 0.109+/-0.067 microg/L; <0.05) in the indirect UVB exposure group significantly increased, while serum levels of 25-(OH)D significantly decreased (28.67+/-1.35 nmol/L vs 34.69+/-4.30 nmol/L; <0.01). There were no significant differences in BMD and serum levels of BALP and ICTP between the indirect UVB exposure and the direct UVB exposure groups. UVB irradiation through glass cannot elevate serum levels of 25-(OH)D, but can decrease bone turnover rate and increase BMD. The effect of UVB irradiation through glass on bone metabolism is similar to that of direct UVB irradiation.

Protective effect of pomegranate derived products on UVB-mediated damage in human reconstituted skin

PubMed Central

Afaq, Farrukh; Zaid, Mohammad Abu; Khan, Naghma; Dreher, Mark; Mukhtar, Hasan

2010-01-01

Solar ultraviolet (UV) radiation, particularly its UVB (290-320 nm) component, is the primary cause of many adverse biological effects including photoaging and skin cancer. UVB radiation causes DNA damage, protein oxidation and induces matrix metalloproteinases (MMPs). Photochemoprevention via the use of botanical antioxidants in affording protection to human skin against UVB damage is receiving increasing attention. Pomegranate, from the tree Punica granatum contains anthocyanins and hydrolyzable tannins and possesses strong anti-oxidant and anti-tumor promoting properties. In this study, we determined the effect of pomegranate derived products POMx juice, POMx extract and pomegranate oil (POMo) against UVB-mediated damage using reconstituted human skin (EpiDerm™ FT-200). EpiDerm was treated with POMx juice (1-2 μl/0.1 ml/well), POMx extract (5-10 μg/0.1 ml/well), and POMo (1-2 μl/0.1 ml/well) for 1 h prior to UVB (60 mJ/cm2) irradiation and was harvested 12 h post-UVB to assess protein oxidation, markers of DNA damage and photoaging by western blot analysis and immunohistochemistry. Pretreatment of Epiderm with pomegranate derived products resulted in inhibition of UVB-induced (i) cyclobutane pyrimidine dimers, (ii) 8-dihydro-2′-deoxyguanosine, (iii) protein oxidation, and (iv) PCNA protein expression. We also found that pretreatment of Epiderm with pomegranate derived products resulted in inhibition of UVB-induced (i) collagenase (MMP-1), (ii) gelatinase (MMP-2, MMP-9), (iii) stromelysin (MMP-3), (iv) marilysin (MMP-7), (v) elastase (MMP-12), and (vi) tropoelastin. Gelatin zymography revealed that pomegranate derived products inhibited UVB-induced MMP-2 and MMP-9 activities. Pomegranate derived products also caused a decrease in UVB-induced protein expression of c-Fos and phosphorylation of c-Jun. Collectively, these results suggest that all three pomegranate derived products may be useful against UVB-induced damage to human skin. PMID:19320737

Combination treatment with excimer laser and narrowband UVB light in vitiligo patients.

PubMed

Shin, Sungsik; Hann, Seung-Kyung; Oh, Sang Ho

2016-01-01

For the treatment of vitiligo, narrowband UVB (NBUVB) light is considered the most effective for nonsegmental vitiligo, while excimer laser treatment is commonly used for localized vitiligo. However, treatment areas may potentially be missed with excimer laser treatment. We aimed to evaluate the effect of combinational treatment with NBUVB light and excimer laser on vitiligo. All patients were first treated with NBUVB; excimer laser was then applied in conjunction with NBUVB phototherapy due to a slow response or no further improvement with continuous NBUVB treatment alone. To minimize adverse effects, a fixed dose of NBUVB was administered, and the dose of excimer laser was increased based on patient response. Among 80 patients, 54 patients showed responses after combination with excimer laser; however, 26 patients (32.5%) showed no remarkable change after combination therapy. Of the 26 patients who showed no further response, 12 patients (46.1%) presented with vitiligo on the acral areas, which are known to the least responsive sites. Our study suggests that combined treatment of NBUVB and excimer laser in vitiligo may enhance the treatment response without remarkable side effects, therefore might also increase the compliance of the patients to the treatment. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Topical treatment and combination approaches for vitiligo: new insights, new developments.

PubMed

Hossani-Madani, A R; Halder, R M

2010-02-01

Despite much research done involving elucidation of the pathogenesis of vitiligo, a precise cause is still not known. Prevalent hypotheses include the autoimmune, genetic, neural, self-destruction, growth factor deficiency, viral, and convergence theories, which have served as the basis for treatment formulation. Topical therapies have been a mainstay of vitiligo treatment, with or without phototherapy. Topical treatments used in the treatment of vitiligo include steroids, calcineurin inhibitors, vitamin D analogues, pseudocatalase, and depigmenting agents. Combination therapies are used to improve the success rate of repigmentation. In this article, we have examined randomized controlled trials utilizing topical treatments used as monotherapy or combination therapy. Although psoralen and khellin can be used as topical agents, used in conjunction with UV radiation, we have not included them in the review due to their inability to be used as monotherapy. We have also excluded less used or ineffective topical agents, such as melagenina, topical phenylalanine, topical L-DOPA, coal tar, anacarcin forte oil and topical minoxidil. According to current guidelines, a less than two month trial of potent or very potent topical corticosteroids or topical calcineurin inhibitors may be used for therapy of localized vitiligo (<20% skin surface area). Combinations of topical corticosteroids with excimer laser and UVA seem to be more effective than steroids alone. Pseudocatalase plus NB-UVB does not seem to be more effective than placebo with NB-UVB. Combinations of vitamin D analogues have varied efficacy based on which type is used and the type of UV light. Efficacy of calcineurin inhibitor combinations also vary based on the type used and UV light combined, with tacrolimus being more effective with excimer laser. Pimecrolimus has been effective with NB-UVB and excimer laser on facial lesions, and microdermabrasion on localized areas.

Concentration of selenium, zinc, copper, Cu/Zn ratio, total antioxidant status and c-reactive protein in the serum of patients with psoriasis treated by narrow-band ultraviolet B phototherapy: A case-control study.

PubMed

Wacewicz, Marta; Socha, Katarzyna; Soroczyńska, Jolanta; Niczyporuk, Marek; Aleksiejczuk, Piotr; Ostrowska, Jolanta; Borawska, Maria H

2017-12-01

Psoriasis is a common, an inflammatory skin disease. Trace elements may play an active role in the pathogenesis of psoriasis. The aim of this study was to estimate the concentration of selenium (Se), zinc (Zn), copper (Cu) and Cu/Zn ratio as well as total antioxidant status (TAS) and c-reactive protein (CRP) in the serum of patients with psoriasis. In this case-control study sixty patients with psoriasis and fifty-eight healthy people were examined. Serum levels of Se, Zn and Cu were determined by atomic absorption spectrometry. Cu/Zn ratio was calculated. TAS was measured spectrophotometrically. CRP was analyzed by immunoturbidimetric method. Clinical activity of psoriasis was evaluated using Psoriasis Area and Severity Index (PASI). Serum concentration of Se in patients with psoriasis (71.89±16.90μg/L) was lower as compared to the control group (79.42±18.97μg/L) and after NB-UVB. Cu level of patients was higher (1.151±0.320mg/L) as compared to controls (1.038±0.336mg/L), but Zn level did not differ. We observed higher Cu/Zn ratio (p<0.05) in examined patients than in the control group and after NB-UVB. We found decrease TAS before and after NB-UVB. CRP levels was found to be normal range. A significant correlation coefficient between CRP and Cu/Zn was observed. The study showed some disturbances in the serum levels of trace elements and TAS in psoriatic patients. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

Intake of high-fat diet stimulates the risk of ultraviolet radiation-induced skin tumors and malignant progression of papillomas to carcinoma in SKH-1 hairless mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaid, Mudit; Singh, Tripti; Prasad, Ram

Previously, we showed that administration of a high-fat diet (HF-diet) to C57BL/6 mice exacerbates their response to short-term UVB radiation-induced inflammation in the skin. To explore the effects of an HF-diet on UVB-induced tumorigenesis, we have used the SKH-1 hairless mouse model in which the mice are exposed to UVB radiation (180 mJ/cm{sup 2}) three times a week for 24 weeks. The development of UVB-induced skin tumors was rapid and the tumor multiplicity and tumor size were significantly higher (P < 0.01–0.005) in the mice fed an HF-diet than the mice fed a control-diet (C-diet). Moreover, the malignant progression ofmore » UVB-induced papillomas to carcinomas was higher in HF-diet-fed mice. On analysis of tumors and tumor-uninvolved skin samples from the tumor-bearing mice, we found that administration of an HF-diet significantly enhanced the levels of UVB-induced expression of cyclooxygenase-2 (COX-2), prostaglandin E{sub 2} (P < 0.01), and PGE{sub 2} receptors, and activation of NF-κB in the UVB-exposed skin as well as in tumors. In addition the HF-diet enhanced the expression of proinflammatory cytokines, including tumor necrosis factor-α (P < 0.01), interleukin (IL)-1β (P < 0.01) and IL-6 (P < 0.05) in the UVB-exposed skin as well as in tumors. Western blot analysis revealed that HF-diet enhanced the levels of epidermal cell proliferation, phosphatidylinositol 3-kinase and phosphorylation of Akt at Ser{sup 473} in UVB-exposed skin and skin tumors. Collectively, these data demonstrate that the regular consumption of an HF-diet increases the risk of photocarcinogenesis in mice and that this is associated with enhanced expression of inflammatory mediators in the UVB-exposed skin and tumors. - Highlights: • Consumption of high-fat diet increases UVB-induced skin tumor development in mice. • Intake of high-fat diet stimulates progression of UV-induced papilloma to carcinoma. • Intake of high-fat diet enhances inflammation in UV-exposed skin • Regular consumption of low-fat diet may inhibit the risk of photocarcinogenesis.« less

Antioxidant responses of damiana (Turnera diffusa Willd) to exposure to artificial ultraviolet (UV) radiation in an in vitro model; part ii; UV-B radiation.

PubMed

Soriano-Melgar, Lluvia de Abril Alexandra; Alcaraz-Meléndez, Lilia; Méndez-Rodríguez, Lía C; Puente, María Esther; Rivera-Cabrera, Fernando; Zenteno-Savín, Tania

2014-05-01

Ultraviolet type B (UV-B) radiation effects on medicinal plants have been recently investigated in the context of climate change, but the modifications generated by UV-B radiation might be used to increase the content of antioxidants, including phenolic compounds. To generate information on the effect of exposure to artificial UV-B radiation at different highdoses in the antioxidant content of damiana plants in an in vitro model. Damiana plantlets (tissue cultures in Murashige- Skoog medium) were irradiated with artificial UV-B at 3 different doses (1) 0.5 ± 0.1 mW cm-2 (high) for 2 h daily, (2) 1 ± 0,1 mW cm-2 (severe) for 2 h daily, or (3) 1 ± 0.1 mW cm-2 for 4 h daily during 3 weeks. The concentration of photosynthetic pigments (chlorophylls a and b, carotenoids), vitamins (C and E) and total phenolic compounds, the enzymatic activity of superoxide dismutase (SOD, EC 1.15.1.1) and total peroxidases (POX, EC 1.11.1), as well as total antioxidant capacity and lipid peroxidation levels were quantified to assess the effect of high artificial UV-B radiation in the antioxidant content of in vitro damiana plants. Severe and high doses of artificial UV-B radiation modified the antioxidant content by increasing the content of vitamin C and decreased the phenolic compound content, as well as modified the oxidative damage of damiana plants in an in vitro model. UV-B radiation modified the antioxidant content in damiana plants in an in vitro model, depending on the intensity and duration of the exposure. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

New apparatus with high radiation energy between 320 to 460 nm: physical description and dermatological applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mutzhas, M.F.; Holzle, E.; Hofmann, C.

1981-01-01

A new apparatus (UVASUN 5000) is presented with high radiation energy between 320 to 460 nm. The radiator is a specially developed source for high uv-A intensity, housing a quartz bulb with a mixture of argon, mercury and metal-halides. The uv-A energy in the range of 320 to 400 nm is about 84% of the total radiation energy. Effects of very high doses of uv-A on human skin were studied. Following single uv-A applications the minimal tanning dose uv-A (MTD) and the immediate pigment darkening (IPD) dose of uv-A were established. Repeated exposure to this uv-A delivering system yields longmore » lasting dark brown skin pigmentation without any clinical or histological signs of sunburn (uv-B) damage, epidermal hyperplasia or thickening of the stratum corneum. Minimal therapeutic results were seen in the phototherapy of vitiligo and inflammatory acne.« less

Inhibition of UV-B Induced Apoptosis in Corneal Epithelial Cells by Potassium Channel Modulators

PubMed Central

Ubels, John L.; Schotanus, Mark P.; Bardolph, Susan L.; Haarsma, Loren D.; Koetje, Leah R.; Louters, Julienne R.

2009-01-01

The goal of this study was to determine whether prevention of K+ loss can protect human corneal-limbal epithelial (HCLE) cells from UV-B induced apoptosis. Immunostaining for activated caspase-3 of HCLE cells exposed to 150 – 200 mJ/cm2 UV-B demonstrated induction of apoptosis 6 hrs after exposure. The number of apoptotic cells was decreased by incubation in medium with 25 or 100 mM K+. If this protection is due to a reduction of UV induced K+ loss then K+ channel blockers should also protect HCLE cells from UV-B. Caspase-8 activity induced by exposure to UV-B at 150 mJ/cm2 was significantly reduced when the cells were incubated in 0.3 µM BDS-I or 0.05–1 mM quinidine. Caspase-3 was also activated by UV-B and a reduction in activity was observed after incubation in 0.1–0.3 µM BDS-I and 0.1–1mM quinidine. Induction of DNA fragmentation, as measured by the TUNEL assay, was decreased by treatment with 0.3 µM BDS-I and 0.01–0.05 mM quinidine. Patch-clamp recording showed activation of K+ channels after exposure to UV-B and a decrease in outward K+ current was observed following application of BDS-I. Quinidine did not block K+ currents in HCLE cells, suggesting that the protective effect of quinidine occurs by a mechanism other than via K+ channels. The effect of the K+ channel blocker BDS-1 on HCLE cells exposed to UV-B confirms that preventing K+ efflux protects corneal epithelial cells from apoptosis. This suggests the elevated [K+] in tears may protect the corneal epithelium from effects of ambient UV-B. PMID:19874821

Comparison of total oxidant/antioxidant status in unconjugated hyperbilirubinemia of newborn before and after conventional and LED phototherapy: A prospective randomized controlled trial.

PubMed

Demirel, Gamze; Uras, Nurdan; Celik, Istemi H; Aksoy, Hatice T; Oguz, Serife S; Erdeve, Omer; Erel, Ozcan; Dilmen, Ugur

2010-10-01

We evaluated and compared the oxidant and antioxidant status of hyperbilirubinemic infants before and after the two forms of phototherapy: conventional and LED phototherapy, in order to identify the optimal treatment method. Thirty newborns exposed to conventional (Group I) phototherapy and 30 infants exposed to LED phototherapy (Group II) were studied. The serum total antioxidant capacity (TAC) and the total oxidant status (TOS) were assessed by EREL's method. There were no statistically significant differences in TAC or TOS levels between Group I and Group II prior to phototherapy, and no statistically significant difference in TAC levels between the two groups after phototherapy; however, TOS levels were significantly lower in Group II compared to Group I after phototherapy. Oxidative stress index (OSI) increased after conventional phototherapy (p < 0.05) The increase in TOS following conventional phototherapy was not not observed following LED phototherapy. This difference should be considered when using phototherapy.

Direct and Indirect Effects of UV-B Exposure on Litter Decomposition: A Meta-Analysis

PubMed Central

Song, Xinzhang; Peng, Changhui; Jiang, Hong; Zhu, Qiuan; Wang, Weifeng

2013-01-01

Ultraviolet-B (UV-B) exposure in the course of litter decomposition may have a direct effect on decomposition rates via changing states of photodegradation or decomposer constitution in litter while UV-B exposure during growth periods may alter chemical compositions and physical properties of plants. Consequently, these changes will indirectly affect subsequent litter decomposition processes in soil. Although studies are available on both the positive and negative effects (including no observable effects) of UV-B exposure on litter decomposition, a comprehensive analysis leading to an adequate understanding remains unresolved. Using data from 93 studies across six biomes, this introductory meta-analysis found that elevated UV-B directly increased litter decomposition rates by 7% and indirectly by 12% while attenuated UV-B directly decreased litter decomposition rates by 23% and indirectly increased litter decomposition rates by 7%. However, neither positive nor negative effects were statistically significant. Woody plant litter decomposition seemed more sensitive to UV-B than herbaceous plant litter except under conditions of indirect effects of elevated UV-B. Furthermore, levels of UV-B intensity significantly affected litter decomposition response to UV-B (P<0.05). UV-B effects on litter decomposition were to a large degree compounded by climatic factors (e.g., MAP and MAT) (P<0.05) and litter chemistry (e.g., lignin content) (P<0.01). Results suggest these factors likely have a bearing on masking the important role of UV-B on litter decomposition. No significant differences in UV-B effects on litter decomposition were found between study types (field experiment vs. laboratory incubation), litter forms (leaf vs. needle), and decay duration. Indirect effects of elevated UV-B on litter decomposition significantly increased with decay duration (P<0.001). Additionally, relatively small changes in UV-B exposure intensity (30%) had significant direct effects on litter decomposition (P<0.05). The intent of this meta-analysis was to improve our understanding of the overall effects of UV-B on litter decomposition. PMID:23818993

[Localized scleroderma (morphea) in childhood].

PubMed

Weibel, L

2012-02-01

Localized scleroderma or morphea is a sclerosing connective tissue disease of the skin, which may affect underlying tissues such as subcutis, muscle and bone. Many patients show extracutaneous symptoms and antinuclear antibodies, however, secondary transformation into systemic sclerosis does not occur. Localized scleroderma usually begins in childhood with a wide variation in its clinical spectrum. The linear variant is the most common subtype in children, associated with a progressive course and increased risk of complications. The disease may progress over years and result in severe functional and cosmetic disability. The etiology of localized scleroderma remains unknown. A genetic background is suspected, while triggers such as trauma, vaccinations and infections may lead to secondary immunologic phenomena. Localized scleroderma often remains unrecognized for a long time, resulting in substantial delay in treatment. The combination of systemic corticosteroids and methotrexate has been established as first-line therapy for progressive (usually linear) disease, whereas phototherapy (UVA-1 or UVB-narrow band) is suitable for adolescents with superficial circumscribed subtypes.

Photochemoprevention of UVB-induced skin carcinogenesis in SKH-1 mice by brown algae polyphenols.

PubMed

Hwang, Hyejeong; Chen, Tong; Nines, Ronald G; Shin, Hyeon-Cheol; Stoner, Gary D

2006-12-15

Chronic exposure of the skin to ultraviolet B (UVB) radiation induces oxidative stress, which plays a crucial role in the induction of skin cancer. In this study, the effect of dietary feeding and topical application of brown algae polyphenols on UVB radiation-induced skin carcinogenesis in SKH-1 mice was investigated. SKH-1 hairless mice were randomly divided into 9 groups, including control, UVB control and treatment groups. They were treated orally (0.1% and 0.5% with AIN-76 diet, w/w) and topically (3 and 6 mg/0.2 ml of vehicle) with brown algae polyphenols and irradiated with UVB for 26 weeks. Dietary feeding (0.1% and 0.5%) of brown algae polyphenols significantly reduced tumor multiplicity (45% and 56%) and tumor volume (54% and 65%), and topical administration (3 and 6 mg) significantly decreased tumor multiplicity (60% and 46%) and tumor volume (66% and 57%), respectively, per tumor-bearing mouse. Dietary feeding and topical administration of the polyphenols also inhibited tumor incidence by 6% and 21%, respectively, but the results were not significant. Dietary and topical administration of the polyphenols markedly inhibited cyclooxygenase-2 activity and cell proliferation. These observations show that brown algae polyphenols have an antiphotocarcinogenic effect which may be associated with the prevention of UVB-induced oxidative stress, inflammation, and cell proliferation in the skin. Copyright 2006 Wiley-Liss, Inc.

Hole doping and structural transformation in CsTl1-xHgxCl3.

PubMed

Retuerto, Maria; Yin, Zhiping; Emge, Thomas J; Stephens, Peter W; Li, Man-Rong; Sarkar, Tapati; Croft, Mark C; Ignatov, Alexander; Yuan, Z; Zhang, S J; Jin, Changqing; Paria Sena, Robert; Hadermann, Joke; Kotliar, Gabriel; Greenblatt, Martha

2015-02-02

CsTlCl(3) and CsTlF(3) perovskites have been theoretically predicted to be superconductors when properly hole-doped. Both compounds have been previously prepared as pure compounds: CsTlCl(3) in a tetragonal (I4/m) and a cubic (Fm3̅m) perovskite polymorph and CsTlF(3) as a cubic perovskite (Fm3̅m). In this work, substitution of Tl in CsTlCl(3) with Hg is reported, in an attempt to hole-dope the system and induce superconductivity. The whole series CsTl(1-x)HgxCl(3) (x = 0.0, 0.1, 0.2, 0.4, 0.6, and 0.8) was prepared. CsTl(0.9)Hg(0.1)Cl(3) is tetragonal as the more stable phase of CsTlCl(3). However, CsTl(0.8)Hg(0.2)Cl(3) is already cubic with the space group Fm3̅m and with two different positions for Tl(+) and Tl(3+). For x = 0.4 and 0.5, solid solutions could not be formed. For x ≥ 0.6, the samples are primitive cubic perovskites with one crystallographic position for Tl(+), Tl(3+), and Hg(2+). All of the samples formed are insulating, and there is no signature of superconductivity. X-ray absorption spectroscopy indicates that all of the samples have a mixed-valence state of Tl(+) and Tl(3+). Raman spectroscopy shows the presence of the active Tl-Cl-Tl stretching mode over the whole series and the intensity of the Tl-Cl-Hg mode increases with increasing Hg content. First-principle calculations confirmed that the phases are insulators in their ground state and that Hg is not a good dopant in the search for superconductivity in this system.

The consequence of phototherapy exposure on oxidative stress status of expressed human milk.

PubMed

Unal, Sezin; Demirel, Nihal; Yaprak Sul, Deniz; Ulubas Isik, Dilek; Erol, Sara; Neselioglu, Salim; Erel, Ozcan; Bas, Ahmet Yagmur

2017-09-04

There exists evidence that phototherapy can disturb the oxidant/antioxidant balance in favor of oxidants. If phototherapy is continued during tube feeding in preterms, expressed human milk is subjected to phototherapy lights for about 20 min per feeding. We aimed to investigate the effects of phototherapy lights on oxidative/antioxidative status of expressed human milk. Milk samples of 50 healthy mothers were grouped as control and phototherapy and exposed to 20 min of day-light and phototherapy light, respectively. Total antioxidant capacity (mmol-Trolox equiv/L) and total oxidant status (mmol-H 2 O 2 /L) in expressed human milk samples were measured. Levels of antioxidant capacity of the expressed human milks in the phototherapy group were lower than those of the control group [mmol-Trolox equiv/L; median (interquartile-range): 1.30 (0.89-1.65) and 1.77 (1.51-2.06), p: < .001]. Levels of oxidant status were similar in both groups. We demonstrated that phototherapy decreased antioxidant capacity of expressed human milk without any alteration in oxidative status. We think that this observation is important for the care of very low birth weighted infants who have limited antioxidant capacity and are vulnerable to oxidative stress. It may be advisable either to turn off the phototherapy or cover the tube and syringe to preserve antioxidant capacity of human milk during simultaneous tube feeding and phototherapy treatment.

Classical to current approach for treatment of psoriasis: a review.

PubMed

Rahman, Mahfoozur; Alam, Kainat; Ahmad, Mohammad Zaki; Gupta, Gaurav; Afzal, Muhammad; Akhter, Sohail; Kazmi, Imran; Jyoti; Ahmad, Farhan Jalees; Anwar, Firoz

2012-09-01

Psoriasis is a genetic predisposition with T-cell mediated autoimmune inflammatory skin disorder, characterized by cutaneous inflammation, increased epidermal proliferation, hyperkeratosis, angiogenesis, and abnormal keratinization that affects up to 2 - 3% of the population worldwide. Common therapies that are used for the treatment of psoriasis include topical, systemic, phototherapy, combination, herbal therapy and novel molecules. Topically used agents include Vit D, calcipotriol, corticosteroids, dithranol and retinoids etc. Systemically used agents include methotrexate and cyclosporine etc. Phototherapy includes UV-B, Psoralen plus ultraviolet therapy and excimer laser etc. These therapies have a number of potential problems, such as limited in efficacy, inconvenience, organ toxicity, carcinogenic and broadband immunosuppression. In natural treatment a variety of natural agents such as methanolic extracts of duzhong (Eucommia ulmoides Oliv.), yerba mate (Ilex paraguariensis,) linseed oil, fish oil, and Indigo naturalis etc., that modulates T cell and cytokine action at various steps along with the pathogenic sequence have been developed. But till now there is no more in vivo, dose and its efficacy data has been established. Current therapy includes biologicals, small molecules inhibitor and enzyme inhibitors etc, which serve as novel therapeutic options for psoriasis treatment. All these avoid the side effects of the prebiologically developed systemic agents including hepatotoxicity, nephrotoxicity, and bone marrow suppression. Currently, Denilukin diftitox, Efalizumab, Alefacept, Ustekinumab and Etanercept are approved by the FDA, and others molecules are at clinical stage. Patents issued by the US office are also included in current psoriasis treatment scenario. In the United States, biologicals are widely used for moderate-to-severe psoriasis. But because of the high cost of medication and their availability in injection form, it remains to be seen how widely these agents will be utilized worldwide. Still, developing countries prefer conventional drugs.

The contributions of adjusted ambient ultraviolet B radiation at place of residence and other determinants to serum 25-hydroxyvitamin D concentrations.

PubMed

Kelly, D; Theodoratou, E; Farrington, S M; Fraser, R; Campbell, H; Dunlop, M G; Zgaga, L

2016-05-01

Solar ultraviolet B (UVB) radiation is the major source of vitamin D (vitD) for humans. To describe ambient UVB radiation at wavelengths that induce vitD synthesis (vitD-UVB) in Scotland, and to examine the relationship to serum 25-hydroxyvitamin D (25OHD). We estimated the average vitD-UVB dose for each day of the year and for each postcode area in Scotland, using the Tropospheric Emission Monitoring Internet Service database. Cumulative and weighted vitD-UVB (CW-vitD-UVB) exposure at place of residence was calculated for each participant. Plasma 25OHD was assayed in 1964 healthy participants. Significant seasonal and geographical variation in vitD-UVB was observed. Ambient vitD-UVB exposure at place of residence was significantly associated with plasma 25OHD (P < 0·01). An average increase in 25OHD of 1 ng mL(-1) was observed for every 1000 mJ cm(-2) higher CW-vitD-UVB dose or for every 2·5 μg of daily supplement taken. Adequate 25OHD concentration (> 16 ng mL(-1)) was observed in the majority when CW-vitD-UVB dose was > 6000 mJ cm(-2), a level of ambient radiation achieved only in summer months in Scotland. When predicting vitD deficiency, dramatic improvement in the area under the curve was observed (from 0·55 to 0·70) after CW-vitD-UVB dose was added to the model, in addition to a range of other covariates. Ambient vitD-UVB can be a useful predictor of vitD status. Geotemporally mapped measurements of vitD-UVB can be used as a proxy for vitD status or as a covariate in epidemiological research, particularly if 25OHD is unavailable. © 2015 British Association of Dermatologists.

Effect of Ursodeoxycholic Acid on Indirect Hyperbilirubinemia in Neonates Treated With Phototherapy.

PubMed

Honar, Naser; Ghashghaei Saadi, Elham; Saki, Forough; Pishva, Narjes; Shakibazad, Nader; Hosseini Teshnizi, Saeed

2016-01-01

Hyperbilirubinemia is a common neonatal problem. The present study aimed to investigate the effect of ursodeoxycholic acid in reducing indirect hyperbilirubinemia of infants under phototherapy. This double-blind randomized clinical trial was conducted on neonates with jaundice, who had received phototherapy in the hospitals affiliated with the Shiraz University of Medical Sciences in 2013. A total of 80 neonates were enrolled in the study and were randomly divided into 2 groups. The intervention group (n =  0) with indirect hyperbilirubinemia received 10 mg · kg(-1) · day(-1) divided every 12 hours Ursobil (capsule 300 mg) in addition to phototherapy, whereas the control group (n =  0) received only phototherapy. Total bilirubin levels were measured every 12 hours until reaching <10 mg/dL, and then phototherapy was disrupted. The duration of phototherapy was measured. The 2 groups were compared regarding total bilirubin levels at different time points and duration of phototherapy using the generalized estimating equation (GEE) test. The mean of total bilirubin in the intervention group was 12 ± 1.6, 10 ± 1.1, and 9.8 ± 0.2 mg/dL 12, 24, and 48 hours after the beginning of phototherapy, respectively. On the contrary, these measures were 14.4 ± 1.3, 12.5 ± 1.4, and 10.1 ± 1.1 mg/dL in the control group, respectively, (P < 0.05). The mean time required for phototherapy to decrease the bilirubin level to < 10 mg/dL was 15.5 ± 6 and 44.6 ± 13.3 hours in the case and the control group, respectively, (P = 0.001). Ursodeoxycholic acid had additive effect with phototherapy in neonates with indirect hyperbilirubinemia. This drug also reduced the time period needed for phototherapy and, consequently, decreased the hospitalization period.

The flavonoid hesperidin exerts anti-photoaging effect by downregulating matrix metalloproteinase (MMP)-9 expression via mitogen activated protein kinase (MAPK)-dependent signaling pathways.

PubMed

Lee, Hee Jeong; Im, A-Rang; Kim, Su-Man; Kang, Hyung-Sik; Lee, Jae Dong; Chae, Sungwook

2018-01-30

Hesperidin is a flavonoid with antioxidant, anti-inflammatory, and immune modulatory activities. Photoaging is a consequence of chronic exposure to the sun and ultraviolet (UV) radiation. This study was designed to evaluate the efficacy of hesperidin against photoaging of dorsal skin in hairless mice. Hairless male mice (6-week-old) were divided into three groups (n = 7): control, UVB-treated vehicle, and UVB-treated hesperidin groups. UVB-irradiated mice from hesperidin group were orally administered 0.1 mL of water containing 100 mg/kg body weight per day hesperidin. The mean length and depth of wrinkles in the UVB-treated hesperidin group significantly improved after the oral administration of hesperidin, which significantly inhibited the increase in epidermal thickness and epidermal hypertrophy (P < 0.05). UVB irradiation of mice induced epidermal barrier dysfunction including an increase in the transepidermal water loss (TEWL); however, hesperidin decreased the TEWL. UVB irradiation increased the expression of MMP-9 and pro-inflammatory cytokines whereas UVB-treated hesperidin group showed reduced expression. These results indicate that hesperidin showed anti-photoaging activity in the UVB-irradiated hairless mice. In conclusion, hesperidin inhibited the UVB-induced increase in skin thickness, wrinkle formation, and collagen fiber loss in male hairless mice. These results suggest that hesperidin shows potent anti-photoaging activity by regulating MMP-9 expression through the suppression of MAPK-dependent signaling pathways.

Temporal Association of HLA-B*81:01- and HLA-B*39:10-Mediated HIV-1 p24 Sequence Evolution with Disease Progression

PubMed Central

Ntale, R. S.; Chopera, D. R.; Ngandu, N. K.; Assis de Rosa, D.; Zembe, L.; Gamieldien, H.; Mlotshwa, M.; Werner, L.; Woodman, Z.; Mlisana, K.; Abdool Karim, S.; Gray, C. M.

2012-01-01

HLA-B*81:01 and HLA-B*39:10 alleles have been associated with viremic control in HIV-1 subtype C infection. Both alleles restrict the TL9 epitope in p24 Gag, and cytotoxic-T-lymphocyte (CTL)-mediated escape mutations in this epitope have been associated with an in vitro fitness cost to the virus. We investigated the timing and impact of mutations in the TL9 epitope on disease progression in five B*81:01- and two B*39:10-positive subtype C-infected individuals. Whereas both B*39:10 participants sampled at 2 months postinfection had viruses with mutations in the TL9 epitope, in three of the five (3/5) B*81:01 participants, TL9 escape mutations were only detected 10 months after infection, taking an additional 10 to 15 months to reach fixation. In the two remaining B*81:01 individuals, one carried a TL9 escape variant at 2 weeks postinfection, whereas no escape mutations were detected in the virus from the other participant for up to 33 months postinfection, despite CTL targeting of the epitope. In all participants, escape mutations in TL9 were linked to coevolving residues in the region of Gag known to be associated with host tropism. Late escape in TL9, together with coevolution of putative compensatory mutations, coincided with a spontaneous increase in viral loads in two individuals who were otherwise controlling the infection. These results provide in vivo evidence of the detrimental impact of B*81:01-mediated viral evolution, in a single Gag p24 epitope, on the control of viremia. PMID:22933291

21 CFR 880.5270 - Neonatal eye pad.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Neonatal eye pad. 880.5270 Section 880.5270 Food... § 880.5270 Neonatal eye pad. (a) Identification. A neonatal eye pad is an opaque device used to cover and protect the eye of an infant during therapeutic procedures, such as phototherapy. (b...

21 CFR 880.5270 - Neonatal eye pad.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Neonatal eye pad. 880.5270 Section 880.5270 Food... § 880.5270 Neonatal eye pad. (a) Identification. A neonatal eye pad is an opaque device used to cover and protect the eye of an infant during therapeutic procedures, such as phototherapy. (b...

[Association between sleep and leukocyte telomere length in middle-aged and older adults].

PubMed

Liu, H F; Li, F; Wang, Y H; Chen, J H; Peng, D X; Chen, J; Tan, L H; Mi, X; Zhao, B H

2017-07-10

Objective: To understand the association between peripheral leukocytes telomere length (TL) and sleep in middle-aged and old adults. Methods: A total of 176 middle-aged and old adults were investigated by using the Pittsburgh Sleep Quality Index and questionnaire. TL was measured by fluorescence quantitative PCR. The correlation and regression analysis between sleep and telomere length was performed. Results: TL had a mean T/S ratio of 0.995±0.23. There was a negative correlation between TL and age ( r =-0.241, P =0.003). With increasing age, sleep quality became worse ( r =-0.230, P <0.01), the time to fall asleep became longer ( r =0.227, P <0.01), sleep duration was shorter ( r =-0.486, P <0.01), sleep efficiency became worse ( r =-0.226, P <0.01). After controlling for the effects of gender, age, marital status, income level, residence, smoking, drinking, physical exercise and disease status, multiple linear regression analysis indicated that sleep quality ( β =0.057, P <0.01), time to fall asleep ( β =-0.046, P <0.01), sleep duration ( β =0.086, P <0.01) were independent influencing factors of telomere length, suggesting that the people who had better sleep quality, the shorter time to fall asleep, the longer sleep time would have longer telomere length. Conclusions: Sleep is a relevant factor affecting TL in middle-aged and elderly population. Good sleep may delay aging by slowing TL. We encourage to conduct health education about the importance of sleep quality in community.

Effect of 5-S-GAD on UV-B-induced cataracts in rats.

PubMed

Kawada, Hiroyoshi; Kojima, Masami; Kimura, Takahito; Natori, Shunji; Sasaki, Kazuyuki; Sasaki, Hiroshi

2009-09-01

5-S-Glutathionyl-N-beta-alanyl-3,4-dihydroxyphenylalanine (5-S-GAD) is a novel antibacterial substance purified from Sarcophaga peregrina (flesh fly) that has both a radical scavenging activity and antioxidative activity. This is a report of an investigation of the effect of 5-S-GAD (eyedrops) on UVB-induced cataracts in rats. Brown Norway male rats (n = 32; 7 weeks old) were treated with either 5-S-GAD 0.1%, 5-SGAD 1%, astaxanthin (AST) 0.1% suspension eyedrops or the vehicle alone (the solution without 5-S-GAD) three times a day (three doses at 5-min intervals each time). The treatment was scheduled 2 days before UV-B exposure and 2 days after UV-B exposure. Exposure to 100-200 mJ/cm(2) UV-B was performed once a week between drug treatments for 9 consecutive weeks, with a total dose of 1200 mJ/cm(2) UV-B. Ocular penetration of 5-S-GAD was analyzed using high-pressure liquid chromatography (HPLC). Cataract formation was documented by an anterior eye segment analysis system once a week under mydriasis. The light-scattering intensity (LSI) of the anterior superficial cortex region was measured. In the eighth to ninth week after the start of UV-B exposure, the LSI of anterior subcapsular lenses of 5-S-GAD-treated groups, as detected by HPLC, was significantly lower (P < 0.05) than that of the control, whereas no such difference was found in the AST-treated group. 5-S-GAD eyedrop application may delay the progression of UV-B-induced cataract in rats.

Bone measurements of infants with hyperbilirubinemia by quantitative ultrasound: the influence of phototherapy.

PubMed

Arıkan, Fatma İnci; Kara, Semra; Bilgin, Hüseyin; Özkan, Fatma; Bilge, Yıldız Dallar

2017-07-01

The purpose of the current study was to investigate the possible effects of phototherapy on bone status of term infants evaluated by measurement of tibial bone speed of sound (SOS). The phototherapy group (n = 30) consisted of children who had undergone phototherapy for at least 24 h and the control group (n = 30) comprised children who had not received phototherapy. Blood samples were obtained from all infants for serum calcium, phosphorus, magnesium, alkaline phosphatase, parathyroid hormone and vitamin D concentrations. The left tibial quantitative ultrasound (QUS) measurements were performed using a commercial device. There was no statistically significant difference between phototherapy-exposed and nonexposed infants in terms of Ca, P, ALP, PTH and vitamin D levels. Comparison of bone SOS between the phototherapy-exposed and control group revealed no statistically difference. Also, no significant difference in Z-score for SOS was observed between those with or without exposure. The data of our study indicate that phototherapy treatment has no impact on bone status in the hyperbilirubinemic infants. Although there is no statistically significant evidence of an excess risk of bone damage following phototherapy, studies with larger sample sizes and longer duration of follow-up are needed to gain a better understanding of its effects.

Ultraviolet-B and water stress effects on growth, gas exchange and oxidative stress in sunflower plants.

PubMed

Cechin, Inês; Corniani, Natália; de Fátima Fumis, Terezinha; Cataneo, Ana Catarina

2008-07-01

The effects and interaction of drought and UV-B radiation were studied in sunflower plants (Helianthus annuus L. var. Catissol-01), growing in a greenhouse under natural photoperiod conditions. The plants received approximately 1.7 W m(-2) (controls) or 8.6 W m(-2) (+UV-B) of UV-B radiation for 7 h per day. The UV-B and water stress treatments started 18 days after sowing. After a period of 12 days of stress, half of the water-stressed plants (including both UV-B irradiated or non-irradiated) were rehydrated. Both drought and UV-B radiation treatments resulted in lower shoot dry matter per plant, but there was no significant interaction between the two treatments. Water stress and UV-B radiation reduced photosynthesis, stomatal conductance and transpiration. However, the amplitude of the effects of both stressors was dependent on the interactions. This resulted in alleviation of the negative effect of drought on photosynthesis and transpiration by UV-B radiation as the water stress intensified. Intercelluar CO(2) concentration was initially reduced in all treatments compared to control plants but it increased with time. Photosynthetic pigments were not affected by UV-B radiation. Water stress reduced photosynthetic pigments only under high UV-B radiation. The decrease was more accentuated for chlorophyll a than for chlorophyll b. As a measure for the maximum efficiency of photosystem II in darkness F (v)/F (m) was used, which was not affected by drought stress but initially reduced by UV-B radiation. Independent of water supply, UV-B radiation increased the activity of pirogalol peroxidase and did not increase the level of malondialdehyde. On the other hand, water stress did not alter the activity of pirogalol peroxidase and caused membrane damage as assessed by lipid peroxidation. The application of UV-B radiation together with drought seemed to have a protective effect by lowering the intensity of lipid peroxidation caused by water stress. The content of proline was not affected by UV-B radiation but was increased by water stress under both low and high UV-B radiation. After 24 h of rehydration, most of the parameters analyzed recovered to the same level as the unstressed plants.

Hypocalcemia in jaundiced neonates receiving phototherapy

PubMed Central

Khan, Mashal; Malik, Kanwal Altaf; Bai, Rekha

2016-01-01

Objective: To determine the frequency of hypocalcemia in term neonates with jaundice receiving phototherapy. Methods: This was a cross sectional study conducted at Neonatal intensive care unit, National Institute of Child Health, Karachi from 1st January 2014 to 30th December 2014. A total of 123 term neonates with jaundice of either gender managed by phototherapy were enrolled in the study. Gestational age was assessed through modified Ballard scoring. Duration of phototherapy was recorded. A sample of 3 ml of blood was sent to the laboratory for serum calcium level before initiating phototherapy and after 24 hours of continued phototherapy. All the data were recorded in the preformed proforma. Data was analyzed using SPSS version 19. P value <0.05 was taken as significant. Results: The mean age of the neonates was 8.35±6.74 days. Mean gestational age at the time of birth was 39.08±1.37 weeks. Mean duration of jaundice was 2.4±1.20 days. Mean duration of phototherapy was 1.74±0.98 days. Serum calcium level before and after 24 hours of initiating phototherapy was 8.73±0.68 mg/dl and 7.47±0.82mg/dl respectively Frequency of hypocalcemia in term jaundiced neonates receiving phototherapy were observed in 22.76% (28/123). Conclusions: The frequency of hypocalcemia is significant in the jaundiced neonates treated with phototherapy. One needs to be vigilant in dealing neonates in this context while serial monitoring for hypocalcemia and its complications should be considered in institutional policy and research priority. PMID:28083043

Application of blue laser diodes and LEDs in phototherapy for neonatal jaundice

NASA Astrophysics Data System (ADS)

Hamza, Mostafa; Sayed El-Ahl, Mohammad H.; Hamza, Ahmad M.; Hamza, Aya M.; Hamza, Yahya M.

2003-10-01

The authors introduce the design of a compact phototherapy unit capable of fulfilling the recommendations of the clinical use of lasers and LEDs in phototherapy for the treatment of neonatal jaundice. The system keeps the duration of phototherapy to the minimum required for efficient treatment. Our leading clinical experience as well as the wavelength selection rules will be presented.

Protective effect of mango (Mangifera indica L.) against UVB-induced skin aging in hairless mice.

PubMed

Song, Jae Hyoung; Bae, Eun Young; Choi, Goya; Hyun, Jin Won; Lee, Mi Young; Lee, Hye Won; Chae, Sungwook

2013-04-01

Mangifera indica L. (Anacardiaceae) is a medicinal plant whose extracts have been described as an antioxidant with anti-inflammatory and immunomodulatory activities. Skin aging is a consequence of chronic sun exposure to the sun and therefore ultraviolet (UV) radiation. Naturally occurring antioxidants are known to reduce skin aging. Therefore, the aim of the present study was to evaluate the protective role of mango extract against UVB-induced skin aging in hairless mice. HR-1 hairless male mice (6 weeks old) were divided into three groups: control (n = 5), UVB-treated vehicle (n = 5), and UVB-treated mango extract (n = 5) groups. UVB-irradiated mice from the mango extract group were orally administered 0.1 ml of water containing 100 mg of mango extract/kg body weight per day. The inhibitory activity of mango extract on wrinkle formation was determined by the analysis of the skin replica, epidermal thickness based on histological examination, and damage to collagen fiber. The mean length of wrinkles in UVB-treated vehicle group significantly improved after the oral administration of mango extract, which significantly inhibited the increase in epidermal thickness and epidermal hypertrophy (P < 0.05). Furthermore, a marked increase in collagen bundles was observed in the UVB-treated group after the administration of mango extract by Masson's trichrome staining. These results indicate that mango extract showed anti-photoaging activity in UVB-irradiated hairless mice. © 2013 John Wiley & Sons A/S.

Energy transfer from Pr3+ to Gd3+ ions in BaB8O13 phosphor for phototherapy lamps

NASA Astrophysics Data System (ADS)

Tamboli, Sumedha; Nair, Govind B.; Dhoble, S. J.; Burghate, D. K.

2018-04-01

A series of BaB8O13 phosphors doped with different concentrations of Gd3+ ions and co-doped with Pr3+ ions were synthesized by solid state synthesis method. X-ray powder diffraction (XRD) analysis confirmed the formation of the compound in a crystalline and homogeneous form. Scanning Electron Microscopy (SEM) was performed to study the surface morphology of the compound and Fourier Transform Infrared (FT-IR) spectroscopy measurements determined the nature of bonding between elements of the compounds. The photoluminescence (PL) excitation spectra of BaB8O13:Gd3+ phosphor showed excitation peaks at 246 nm, 252 nm and 274 nm. The prominent emission peak was observed at 313 nm which is in narrow band ultraviolet B (NB-UVB) range. Energy transfer was achieved by co-doping Pr3+ ions with Gd3+ ions. PL decay time was also measured for BaB8O13: Gd3+, Pr3+ phosphor. Emission at 313 nm can be used for the treatment of skin diseases.

Current knowledge in Polypodium leucotomos effect on skin protection.

PubMed

Palomino, Olga María

2015-04-01

This article provides an overview of pharmacology, toxicity, pharmacokinetics and clinical data of Polypodium leucotomos L. (PL). PL aerial part has proven to exert antioxidant, photoprotective and immunomodulatory activities; its mechanism of action is complex and includes several activities: (1) PL diminishes the production of reactive oxygen and nitrogen species (ROS, RNS); (2) PL inhibits the photoisomerization of trans-urocanic acid (t-UCA); (3) PL inhibits apoptosis induced by ultraviolet radiation; (4) PL prevents damage to genetic material and (5) PL enhances DNA repair. PL is not mutagenic and does not induce acute or chronic toxicity. Its biological effects have been proved in cell cultures, animal models, murine models and in human beings. Photoprotective activity has been assessed in healthy volunteers as well as in patients suffering from several cutaneous diseases such as vitiligo, psoriasis, idiopathic photodermatosis or melasma. PL results to be an efficient treatment especially for sensitive cutaneous phototypes and adds extra protection when ultraviolet radiation (UVR) exposure cannot be avoided, such as wide or narrow band UVB phototherapy or treatment with psoralens plus UVA exposure radiation.

Phototoxic effects of topical azelaic acid, benzoyl peroxide and adapalene were not detected when applied immediately before UVB to normal skin.

PubMed

Cetiner, Salih; Ilknur, Turna; Ozkan, Sebnem

2004-01-01

The enhancing effects on UVB erythema of topical agents applied on sun exposed areas are important due to their increased sunburn risk. Since the lesions in acne vulgaris are seen primarily on the face, the effects of topical agents used in acne treatment on the erythemogenicity of UVB is important. The aim of the present study was to examine whether azelaic acid cream, benzoyl peroxide gel, adapalene gel have the enhancing effects on UVB erythema which are widely used in the topical treatment of acne vulgaris. The minimal erythema dose (MED) was determined with phototest in 30 volunteers and the test was repeated with thin (0.1 cc/25 cm(2)) and thick (0.3 cc/25 cm(2)) azelaic acid cream, benzoyl peroxide gel, adapalene gel. The effects of each agent on MED was determined after 24 hours. MEDs of UVB were unaffected by azelaic acid cream, benzoyl peroxide gel and adapalene gel when applied immediately before irradiation. According to our results azelaic acid, benzoyl peroxide and adapalene do not seem to have enhancing effects on UVB erythema and thus increased sunburn risk.

Thallium isotope variations in an ore-bearing continental igneous setting: Collahuasi Formation, northern Chile

NASA Astrophysics Data System (ADS)

Baker, R. G. A.; Rehkämper, M.; Ihlenfeld, C.; Oates, C. J.; Coggon, R.

2010-08-01

Thallium is a highly incompatible element and a large fraction of the bulk silicate Earth Tl budget is, therefore, expected to reside in the continental crust. Nonetheless, the Tl isotope systematics of continental rocks are essentially unexplored at present. Here, we present new Tl isotope composition and concentration data for a suite of 36 intrusive and extrusive igneous rocks from the vicinity of porphyry Cu deposits in the Collahuasi Formation of the Central Andes in northern Chile. The igneous lithologies of the rocks are variably affected by the hydrothermal alteration that accompanied the formation of the Cu deposits. The samples display Tl concentrations that vary by more than an order of magnitude, from 0.1 to 3.2 μg/g, whilst ɛ 205Tl ranges between -5.1 and +0.1 (ɛ 205Tl is the deviation of the 205Tl/ 203Tl isotope ratio of a sample from a standard in parts per 10 4). These variations are primarily thought to be a consequence of hydrothermal alteration processes, including metasomatic transport of Tl, and formation/breakdown of Tl-bearing minerals, which are associated with small but significant Tl isotope effects. The Tl abundances show excellent correlations with both K and Rb concentrations but no co-variation with Cu. This demonstrates that Tl displays only limited chalcophile affinity in the continental crust of the Collahuasi Formation, but behaves as a lithophile element with a distribution that is primarily governed by partitioning of Tl + into K +-bearing phases. Collahuasi samples with propylitic alteration features, which are derived from the marginal parts of the hydrothermal systems, have, on average, slightly lighter Tl isotope compositions than rocks from the more central sericitic and argillic alteration zones. This small but statistically significant difference most likely reflects preferential retention of isotopically heavy Tl in alteration phases, such as white micas and clays, which formed during sericitic and argillic alteration.

Blue Light and Ultraviolet Radiation Exposure from Infant Phototherapy Equipment.

PubMed

Pinto, Iole; Bogi, Andrea; Picciolo, Francesco; Stacchini, Nicola; Buonocore, Giuseppe; Bellieni, Carlo V

2015-01-01

Phototherapy is the use of light for reducing the concentration of bilirubin in the body of infants. Although it has become a mainstay since its introduction in 1958, a better understanding of the efficacy and safety of phototherapy applications seems to be necessary for improved clinical practices and outcomes. This study was initiated to evaluate workers' exposure to Optical Radiation from different types of phototherapy devices in clinical use in Italy. During infant phototherapy the staff monitors babies periodically for around 10 min every hour, and fixation of the phototherapy beam light frequently occurs: almost all operators work within 30 cm of the phototherapy source during monitoring procedures, with most of them commonly working at ≤25 cm from the direct or reflected radiation beam. The results of this study suggest that there is a great variability in the spectral emission of equipments investigated, depending on the types of lamps used and some phototherapy equipment exposes operators to blue light photochemical retinal hazard. Some of the equipment investigated presents relevant spectral emission also in the UVA region. Taking into account that the exposure to UV in childhood has been established as an important contributing factor for melanoma risk in adults and considering the high susceptibility to UV-induced skin damage of the newborn, related to his pigmentary traits, the UV exposure of the infant during phototherapy should be "as low as reasonably achievable," considering that it is unnecessary to the therapy. It is recommended that special safety training be provided for the affected employees: in particular, protective eyewear can be necessary during newborn assistance activities carried out in proximity of some sources. The engineering design of phototherapy equipment can be optimized. Specific requirements for photobiological safety of lamps used in the phototherapy equipment should be defined in the safety product standard for such equipment.

The effect of actinoquinol with hyaluronic acid in eye drops on the optical properties and oxidative damage of the rabbit cornea irradiated with UVB rays.

PubMed

Čejka, Čestmír; Luyckx, Jacques; Ardan, Taras; Pláteník, Jan; Širc, Jakub; Michálek, Jiří; Čejková, Jitka

2010-01-01

Irradiation of the cornea with UVB rays leads to its oxidative damage, swelling and increased light absorption. We investigated changes in the corneal optics (evaluated by changes of corneal hydration and light absorption) and microscopical disturbances of corneas irradiated with UVB rays as influenced by eye drops containing actinoquinol with hyaluronic acid. Rabbit corneas were irradiated with a daily dose of 0.5 or 1.01 J cm(-2) of UVB rays (312 nm) for 4 days. During irradiation, the eye drops were applied on the right eye and buffered saline (or hyaluronic acid) on the left eye. On day 5 the rabbits were sacrificed and the corneas examined spectrophotometrically for light absorption. The corneal thickness (hydration) was measured using a pachymeter. Corneas of some other rabbits were examined immunohistochemically. After buffered saline treatment UVB rays evoked changes in the corneal optics and induced oxidative damage of the corneas. After actinoquinol-hyaluronic acid application, these changes were diminished. Hyaluronic acid alone was less effective. In conclusion, actinoquinol-hyaluronic acid eye drops decreased changes in corneal optics and suppressed oxidative damage in the UVB-irradiated cornea. However, the effective corneal protection by these eye drops was limited to the lower UVB dose. © 2010 The Authors. Journal Compilation. The American Society of Photobiology.

Growing Up Or Growing Old? Cellular Aging Linked With Testosterone Reactivity To Stress In Youth

PubMed Central

Drury, Stacy S.; Shirtcliff, Elizabeth A.; Shachet, Andrew; Phan, Jenny; Mabile, Emily; Brett, Zoë H.; Wren, Michael; Esteves, Kyle; Theall, Katherine P.

2014-01-01

Background Given the established relation between testosterone and aging in older adults, we tested whether buccal telomere length (TL), an established cellular biomarker of aging, was associated with testosterone levels in youth. Methods Children, mean age 10.2 years, were recruited from the greater New Orleans area and salivary testosterone was measured during both an acute stressor and diurnally. Buccal TL was measured using monochrome multiplex quantitative real-time PCR (MMQ-PCR). Testosterone and telomere length data was available on 77 individuals. The association between buccal TL and testosterone was tested using multivariate Generalized Estimating Equations (GEE) to account for clustering of children within families. Results Greater peak testosterone levels (β=-0.87, p < 0.01) and slower recovery (β=-0.56, p < 0.01) and reactivity (β = -1.22, p < 0.01) following a social stressor were significantly associated with shorter buccal TL after controlling for parental age at conception, child age, sex, sociodemographic factors and puberty. No association was initially present between diurnal measurements of testosterone or morning basal testosterone levels and buccal TL. Sex significantly moderated the relation between testosterone reactivity and buccal TL. Conclusions The association between testosterone and buccal TL supports gonadal maturation as a developmentally sensitive biomarker of aging within youth. As stress levels of testosterone were significantly associated with buccal TL, these findings are consistent with the growing literature linking stress exposure and accelerated maturation. The lack of association of diurnal testosterone or morning basal levels with buccal TL bolsters the notion of a shared stress-related maturational mechanism between cellular stress and the hypothalamic pituitary gonadal (HPG) axis. These data provide novel evidence supporting the interaction of aging, physiologic stress and cellular processes as an underlying mechanism linking negative health outcomes and early life stress. PMID:25010187

Effects of Curcuma extract and visible light on adults with plaque psoriasis.

PubMed

Carrion-Gutierrez, Miguel; Ramirez-Bosca, Ana; Navarro-Lopez, Vicente; Martinez-Andres, Asunción; Asín-Llorca, Manuel; Bernd, August; Horga de la Parte, José Francisco

2015-01-01

We conducted a phase IV randomized, double-blind, placebo-controlled, pilot clinical trial to investigate the safety and efficacy of oral curcumin together with local phototherapy in patients with plaque psoriasis. Patients with moderate to severe psoriasis received Curcuma extract orally with real visible light phototherapy (VLRT) or simulated visible light phototherapy (VLST) in the experimental area, while the rest of the body surface was treated with ultraviolet A (UVA) radiation. The endpoints were the number of responders and the temporal course of the response. The secondary outcomes were related to safety and adverse events. Twenty-one patients were included in the study. In the intention-to-treat analysis, no patients included in the VLRT group showed "moderate" or "severe" plaques after the treatment, in contrast to the patients included in the VSLT group (p<0.01). Parallelisms in the evolution of PGA, BSA, and PASI scores were observed in the two groups following the treatment. At the end of the study period, 76% of all patients showed a response in the BSA exposed to UVA. Lesions on the experimental area showed a response in 81% of the patients in the VLRT group and 30% of the patients in the VLST group. There were no study-related adverse events that necessitated participant withdrawal. The results suggested that moderate to severe plaque psoriasis should show a therapeutic response to orally administered Curcuma if activated with visible light phototherapy, a new therapeutic method that would be safer for patients than existing treatments.

Rhinophototherapy: gimmick or an emerging treatment option for allergic rhinitis?

PubMed

Leong, S C

2011-12-01

Photodynamic therapy has been used in treating immune-mediated dermatological conditions such as psoriasis and atopic dermatitis. There are emerging reports on the efficacy of intranasal phototherapy in allergic rhinitis. The aim of this review was to assess intranasal phototherapy in the treatment of allergic rhinitis, with particular emphasis on clinical efficacy, scientific basis and safety. A structured search of the U.S. National Library of Medicine (PubMed), the Cochrane Collaboration library, Google Scholar and ISI Web of Knowledge database was undertaken using MeSH terms `phototherapy` and `rhinitis.` Fourteen full-text articles were available for review. Three different phototherapy medical devices were assessed: (1) Bionase(TM), (2) Allergy Reliever SN206 and (3) Rhinolight(®). Light wavelength used in these devices ranged from red light to ultraviolet. Clinical use of intranasal phototherapy appears to be safe and well tolerated. Most studies demonstrated symptomatic improvement and quality of life scores. No improvement in objective measures of nasal airflow was demonstrated. Beneficial effects of phototherapy on inflammatory markers remain equivocal. Phototherapy treatment results in DNA damage but does not appear to predispose to carcinogenesis. However, long-term prospective studies are required to verify this. The quality of published studies was variable and thus the current strength of recommending intranasal phototherapy is currently weak.

The Vitiligo Working Group recommendations for narrowband ultraviolet B light phototherapy treatment of vitiligo.

PubMed

Mohammad, Tasneem F; Al-Jamal, Mohammed; Hamzavi, Iltefat H; Harris, John E; Leone, Giovanni; Cabrera, Raúl; Lim, Henry W; Pandya, Amit G; Esmat, Samia M

2017-05-01

Treatment of vitiligo with narrowband ultraviolet B light (NBUVB) is an important component of the current standard of care. However, there are no consistent guidelines regarding the dosing and administration of NBUVB in vitiligo, reflected by varied treatment practices around the world. To create phototherapy recommendations to facilitate clinical management and identify areas requiring future research. The Vitiligo Working Group (VWG) Phototherapy Committee addressed 19 questions regarding the administration of phototherapy over 3 conference calls. Members of the Photomedicine Society and a group of phototherapy experts were surveyed regarding their phototherapy practices. Based on comparison and analysis of survey results, expert opinion, and discussion held during conference calls, expert recommendations for the administration of NBUVB phototherapy in vitiligo were created. There were several areas that required further research before final recommendations could be made. In addition, no standardized methodology was used during literature review and to assess the strength of evidence during the development of these recommendations. This set of expert recommendations by the VWG is based on the prescribing practices of phototherapy experts from around the world to create a unified, broadly applicable set of recommendations on the use of NBUVB in vitiligo. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

The use of satellite data to measure ultraviolet-B penetrance and its potential association with age of multiple sclerosis onset.

PubMed

Amram, Ofer; Schuurman, Nadine; Randall, Ellen; Zhu, Feng; Saeedi, Jameelah; Rieckmann, Peter; Yee, Irene; Tremlett, Helen

2018-04-01

Studies have indicated an association between low Ultraviolet B (UVB) exposure and an increased risk of developing multiple sclerosis (MS). Few studies, however, have explored whether UVB exposure is associated with the age at MS symptom onset. We investigated the potential association between cumulative early life ambient UVB exposure and age at MS onset, using satellite data to measure ambient UVB exposure. Adult onset MS patients were selected from the University of British Columbia's MS genetic database (1980-2005). Patients' places of residence from birth to age 18 years were geocoded (latitude and longitude) and assigned UVB values using NASA's Total Ozone Mapping Spectrometer (TOMS) dataset. Linear regression was used to explore the relationship between cumulative UVB exposure (measured for age periods 0-6, 7-12, 13-18, 0-12, and 0-18) and age at MS onset. 3226 patients were included in the analysis. Of these, 74% were female, with an overall mean symptom onset age of 33.3 years. At onset, a total of 2944 (91%) had a relapsing-remitting disease course, 254 (8%) had primary progressive and the disease course for 28 (1%) was unknown. No significant associations between cumulative early life ambient UVB exposure and age at MS onset were observed. Patient sex, MS phenotype, and immigration to Canada after age 18 were significantly associated with age of onset (p < 0.01). Early life ambient UVB, as measured by satellite imagery, was not significantly associated with the age at MS onset. Copyright © 2018 Elsevier B.V. All rights reserved.

Anti-wrinkle effects of Sargassum muticum ethyl acetate fraction on ultraviolet B-irradiated hairless mouse skin and mechanistic evaluation in the human HaCaT keratinocyte cell line

PubMed Central

Song, Jae Hyoung; Piao, Mei Jing; Han, Xia; Kang, Kyoung Ah; Kang, Hee Kyoung; Yoon, Weon Jong; Ko, Mi Hee; Lee, Nam Ho; Lee, Mi Young; Chae, Sungwook; Hyun, Jin Won

2016-01-01

The present study investigated the photoprotective properties of the ethyl acetate fraction of Sargassum muticum (SME) against ultraviolet B (UVB)-induced skin damage and photoaging in a mouse model. HR-1 strain hairless male mice were divided into three groups: An untreated control group, a UVB-irradiated vehicle group and a UVB-irradiated SME group. The UVB-irradiated mice in the SME group were orally administered with SME (100 mg/kg body weight in 0.1 ml water per day) and then exposed to radiation at a dose of 60–120 mJ/cm2. Wrinkle formation and skin damage were evaluated by analysis of skin replicas, epidermal thickness and collagen fiber integrity in the dermal connective tissue. The mechanism underlying the action of SME was also investigated in the human HaCaT keratinocyte cell line following exposure of the cells to UVB at a dose of 30 mJ/cm2. The protein expression levels and activity of matrix metalloproteinase-1 (MMP-1), and the binding of activator protein-1 (AP-1) to the MMP-1 promoter were assessed in the HaCaT cells using western blot analysis, an MMP-1 fluorescent assay and a chromatin immune-precipitation assay, respectively. The results showed that the mean length and depth of the wrinkles in the UVB-exposed hairless mice were significantly improved by oral administration of SME, which also prevented the increase in epidermal thickness triggered by UVB irradiation. Furthermore, a marked increase in collagen bundle formation was observed in the UVB-treated mice with SME administration. SME pretreatment also significantly inhibited the UVB-induced upregulation in the expression and activity of MMP-1 in the cultured HaCaT keratinocytes, and the UVB-enhanced association of AP-1 with the MMP-1 promoter. These results suggested that SME may be useful as an anti-photoaging resource for the skin. PMID:27573915

Targeted Nanomaterials for Phototherapy

PubMed Central

Chitgupi, Upendra; Qin, Yiru; Lovell, Jonathan F.

2017-01-01

Phototherapies involve the irradiation of target tissues with light. To further enhance selectivity and potency, numerous molecularly targeted photosensitizers and photoactive nanoparticles have been developed. Active targeting typically involves harnessing the affinity between a ligand and a cell surface receptor for improved accumulation in the targeted tissue. Targeting ligands including peptides, proteins, aptamers and small molecules have been explored for phototherapy. In this review, recent examples of targeted nanomaterials used in phototherapy are summarized. PMID:29071178

Comparison of Transcutaneous Bilirubin Measurement With Total Serum Bilirubin Levels in Preterm Neonates Receiving Phototherapy.

PubMed

Pendse, Amruta; Jasani, Bonny; Nanavati, Ruchi; Kabra, Nandkishor

2017-08-15

To compare transcutaneous bilirubin with total serum bilirubin in preterm neonates after initiation of phototherapy. Jaundice was assessed in 30 preterm neonates with transcutaneous bilirubin and total serum bilirubin before initiation of phototherapy and at 12 hr after initiation of phototherapy. A photo-occlusive patch was applied over the sternum. Transcutaneous bilirubin has a good correlation with total serum bilirubin after initiation of phototherapy. (r=0.918, P<0.001). Transcutaneous bilirubin at 28-32 weeks of gestation (r = 0.97) was better correlated with total serum bilirubin than those at 32-37 weeks (r =0.88). The correlation was better for neonates <72 hours old (r = 0.96) than those >72 hours of age (r = 0.82). Transcutaneous bilirubin correlates significantly with total serum bilirubin at the patched sternal site after initiation of phototherapy in preterm neonates.

Longer Telomere Length in Elite Master Sprinters: Relationship to Performance and Body Composition.

PubMed

Simoes, Herbert Gustavo; Sousa, Caio Victor; Dos Santos Rosa, Thiago; da Silva Aguiar, Samuel; Deus, Lysleine Alves; Rosa, Erica Carine Campos Caldas; Amato, Angelica Amorim; Andrade, Rosangela Vieira

2017-12-01

Emergent evidence suggests that the long-term healthy lifestyle of master athletes may attenuate aging. We compared telomere length (TL) of high-level master sprinters and non-athlete age-matched controls, and analyzed the relationships of TL with performance and body fat. Elite master sprinters (n=11; aged 50.1±9.2yrs) and healthy untrained controls (n=10; aged 45.4±10.9yrs) had blood samples collected for biochemical and biomolecular analyses. Master sprinters had longer TL, lower body fat and BMI, and a better lipid profile than age-matched controls (p<0.05). A large effect size was verified comparing TL between athletes vs. controls (Cohen's d=1.039), with a significant negative correlation between TL and performance decline per decade (r=-0.624, p<0.01) and a positive correlation of TL and actual performance level (r=0.641, p<0.01). In conclusion, TL of elite master sprinters was longer than their untrained peers, and seems to be not only a marker of health status, but also an indicator of sports longevity since both actual performance level and its decrease over years were related to TL. Further research might assess the TL of elite master endurance athletes for comparison with sprinters, and also investigate the underlying mechanisms by which the attenuation of telomere shortening occurs in master athletes. © Georg Thieme Verlag KG Stuttgart · New York.

Phototherapy causes DNA damage in peripheral mononuclear leukocytes in term infants.

PubMed

Aycicek, Ali; Kocyigit, Abdurrahim; Erel, Ozcan; Senturk, Hakan

2008-01-01

Our aim was to determine whether endogenous mononuclear leukocyte DNA strand is a target of phototherapy. The study included 65 term infants aged between 3-10 days that had been exposed to intensive (n = 23) or conventional (n = 23) phototherapy for at least 48 hours due to neonatal jaundice, and a control group (n = 19). DNA damage was assayed by single-cell alkaline gel electrophoresis (comet assay). Plasma total antioxidant capacity and total oxidant status levels were also measured, and correlation between DNA damage and oxidative stress was investigated. Mean values of DNA damage scores in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p < 0.001). Mean values and standard deviation were 32 (9), 28 (9), 21 (7) arbitrary unit, respectively. Total oxidant status levels in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p = 0.005). Mean (standard deviation) values were 18.1 (4.2), 16.9 (4.4), 13.5 (4.2) micromol H2O2 equivalent/L, respectively. Similarly, oxidative stress index levels in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p = 0.041). Plasma total antioxidant capacity and total bilirubin levels did not differ between the groups (p > 0.05). There were no significant correlations between DNA damage scores and bilirubin, total oxidant status and oxidative stress levels in either phototherapy group (p > 0.05). Both conventional phototherapy and intensive phototherapy cause endogenous mononuclear leukocyte DNA damage in jaundiced term infants.

Psychosocial resources and the relationship between transformational leadership and employees' psychological strain.

PubMed

Schmidt, Burkhard; Loerbroks, Adrian; Herr, Raphael; Litaker, David; Wilson, Mark; Kastner, Michael; Fischer, Joachim

2014-01-01

Leadership behavior may both serve as a supportive resource or as a source of psychological distress in the workplace. Transformational leadership (TL), a behavior of superiors that fosters motivation, empowerment and a sense of teamness, has been associated with employee well-being, but the mechanisms that underlie these effects are unclear. We therefore explored the relationship between TL and stress by examining potential mediating roles for established organizational and personal resources. We used cross-sectional data on TL, psychosocial resources and employee strain from a company wide survey. Linear regression and structural equation modeling assessed potential mediation following the method outlined by Baron and Kenny. In a convenience sample consisting of mostly white-collar employees (n=320, 42.6% male), we observed a relationship between TL and employees' perceived work-related stress that was fully mediated by protective psychosocial resources (ß =-0.33, p< 0.01). Additionally, we found that TL positively affected these resources (ß=0.61; p< 0.01) and that absence of resources led to more psychological strain (ß=-0.54, p<0.01). Transformational leadership seems to be associated with lower stress among employees and a perception of more available psychosocial resources. These findings indicate that TL might serve as a valuable focus for tailored interventions to improve employee health.

Significant positive correlation between sunshine and lactase nonpersistence in Europe may implicate both in similarly altering risks for some diseases.

PubMed

Szilagyi, Andrew; Leighton, Henry; Burstein, Barry; Shrier, Ian

2011-01-01

Decreasing latitude and increasing frequency of population lactase nonpersistence have been reported to diminish risks for several diseases, but the reason for overlap has not been explained. We evaluate, relationships between calculated national annual ultraviolet light B (UVB) exposure, latitude, and national lactose digestion frequencies. Annual UVB exposure and latitude were based on weighted averages from several cities in different countries. Lactase distribution status was based on published data that have been used previously to derive relations with diseases. We compare univariate regression analyses (r(2)(adj), slope) of percentage of lactase nonpersistence with UVB or latitude. We determine, differences between European and non-European sources by multiregression analysis of independent variables. Correlation between UVB and latitude is high (r(2) = 0.89), and between percentage of lactase nonpersistence and either latitude or UVB the correlation is moderately strong with r(2) = 0.51 and 0.46, respectively, with P ≤ 0.01 for both. A more detailed analysis shows that correlations between percentage of lactase nonpersistence and UVB are only significant in Europe, r(2) = 0.59, P < 0.001, whereas outside Europe: r(2) = 0.06, P = 0.16. These relationships raise hypothetical explanations to account for the observed overlap in similar risk modification by the 2 variables.

Gemfibrozil in late preterm and term neonates with moderate jaundice: a randomized controlled trial.

PubMed

Jaikrishan; Kumar, Praveen; Narang, Anil

2009-12-01

To determine, if oral Gemfibrozil is effective in decreasing the duration of phototherapy by at least 24 hours in neonates >34 weeks gestation with non-hemolytic jaundice, as compared to placebo. Double blind placebo controlled randomized controlled trial. Tertiary care neonatal unit in north India. Ninety seven neonates >34 weeks gestation with non-hemolytic jaundice within first 7 days of life requiring phototherapy. Two doses of Gemfibrozil (60 mg/kg/dose) or placebo, 12 hours apart. Babies were treated with single surface special blue light phototherapy. Serum total bilirubin (STB) was measured 8 hourly. Phototherapy was stopped if two consecutive STB values were below phototherapy zone. Duration of phototherapy. The median (IQR) duration of phototherapy was 40 (30, 60) hours in Gemfibrozil and 36 (19, 55) hours in the placebo group (P=0.13). The peak STB levels were 16.8 +/- 2.7 mg/dL and 16.3 +/- 2.3 mg/dL in Gemfibrozil and placebo groups, respectively. No side effect of the drug or placebo was noticed. Two doses of gemfibrozil (60 mg/kg/dose) given 12 hours apart were not able to reduce the duration of phototherapy, or peak bilirubin level in babies > 34 weeks gestation with non-hemolytic jaundice in the first week of life. Gemfibrozil was not associated with any side effects.

Mini Review of TiO2 -Based Multifunctional Nanocomposites for Near-Infrared Light-Responsive Phototherapy.

PubMed

Wang, Meifang; Hou, Zhiyao; Al Kheraif, Abdulaziz A; Xing, Bengang; Lin, Jun

2018-06-25

Phototherapy with the properties of specific spatial/temporal selectivity and minimal invasiveness has been acknowledged as one of the most promising cancer therapy types. Among all the photoactive substance for phototherapy, titanium dioxide (TiO 2 ) nanomaterials are paid more and more attention due to their outstanding photocatalytic properties, prominent biocompatibility, and excellent chemical stability. However, the wide bandgap (3.0-3.2 eV) of TiO 2 limits its absorption only to the ultraviolet (UV) light region. For a long time, UV light-stimulated TiO 2 was applied in the phototherapy researches of tumors located in the skin layer, while it is unsatisfactory for most deep-tissue tumors. Due to the maximum penetration into tissue existing in the near-infrared (NIR) region, how to use NIR light to trigger photochemical reaction of TiO 2 remains a big challenge. In this review, two strategies to develop and construct NIR-triggered TiO 2 -based nanocomposites (NCs) for phototherapy are summarized, and the relevant mechanism and background knowledge of TiO 2 -based phototherapy are also given in order to better understand the application value and current situation of TiO 2 in phototherapy. Finally, the challenges and research directions of TiO 2 in the future clinic phototherapy application are also discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Early exclusive breastfeeding is associated with longer telomeres in Latino preschool children.

PubMed

Wojcicki, Janet M; Heyman, Melvin B; Elwan, Deena; Lin, Jue; Blackburn, Elizabeth; Epel, Elissa

2016-08-01

Telomere length (TL) is a marker of cellular aging, with the majority of lifetime attrition occurring during the first 4 y. Little is known about risk factors for telomere shortening in childhood. We evaluated the relation between early life feeding variables and preschool TL. We assessed the relation between dietary, feeding, and weight-associated risk factors measured from birth and TL from blood samples taken at 4 y of age (n = 108) and 5 y of age (n = 92) in a cohort of urban, Latino children (n = 121 individual children). Feeding variables were evaluated in children with repeat measurements (n = 77). Mean TL (in bp) was associated with exclusive breastfeeding at 4-6 wk of age (adjusted coefficient: 353.85; 95% CI: 72.81, 634.89; P = 0.01), maternal TL (adjusted coefficient: 0.32; 95% CI: 0.11, 0.54; P < 0.01), and older paternal age (adjusted coefficient: 33.27; 95% CI: 4.10, 62.44; P = 0.03). The introduction of other foods or drinks in addition to breast-milk or replacement-milk substitutes before 4-6 wk of age was associated with mean TL at 4 and 5 y of age (adjusted coefficient: -457.01; 95% CI: -720.50, -193.51; P < 0.01). Infant obesity at 6 mo of age and soda consumption at 4 y of age mediated the relation in part between exclusive breastfeeding at 4-6 wk of age and mean TL at 4 and 5 y of age. High soda consumption at 3 y of age was associated with an accelerated attrition from 4 to 5 y of age (adjusted coefficient: -515.14; 95% CI: -986.06, -41.22; P = 0.03). Exclusive breastfeeding at 4-6 wk of age may have long-term effects on child health as evidenced by longer TL at 4 and 5 y of age. © 2016 American Society for Nutrition.

In vitro and in vivo Efficacy of New Blue Light Emitting Diode Phototherapy Compared to Conventional Halogen Quartz Phototherapy for Neonatal Jaundice

PubMed Central

Chang, Yun Sil; Hwang, Jong Hee; Kwon, Hyuk Nam; Choi, Chang Won; Ko, Sun Young; Park, Won Soon; Shin, Son Moon

2005-01-01

High intensity light emitting diodes (LEDs) are being studied as possible light sources for the phototherapy of neonatal jaundice, as they can emit high intensity light of narrow wavelength band in the blue region of the visible light spectrum corresponding to the spectrum of maximal bilirubin absorption. We developed a prototype blue gallium nitride LED phototherapy unit with high intensity, and compared its efficacy to commercially used halogen quartz phototherapy device by measuring both in vitro and in vivo bilirubin photodegradation. The prototype device with two focused arrays, each with 500 blue LEDs, generated greater irradiance than the conventional device tested. The LED device showed a significantly higher efficacy of bilirubin photodegradation than the conventional phototherapy in both in vitro experiment using microhematocrit tubes (44±7% vs. 35±2%) and in vivo experiment using Gunn rats (30±9% vs. 16±8%). We conclude that high intensity blue LED device was much more effective than conventional phototherapy of both in vitro and in vivo bilirubin photodegradation. Further studies will be necessary to prove its clinical efficacy. PMID:15716604

Mist and water condensation inside incubators reduce the efficacy of phototherapy.

PubMed

de Carvalho, Manoel; Torrao, Carolina Turano; Moreira, Maria Elisabeth Lopes

2011-03-01

To measure the irradiance in humidified incubator under three different overhead phototherapy devices. The effective irradiance of three phototherapy devices was assessed by taking a series of irradiance measurements in the illuminated field. Measurements were made with a fixed bandwidth broadband radiometer (380-530 nm). The distance between the light source and the radiometer was 35 cm for the daylight fluorescent lamp, 40 cm for the light emitting diode (LED) and 50 cm for the halogen phototherapy. A double-wall incubator was kept at 36°C and set at three different levels of humidity (60-70%, 80% and equal or above 90%). The irradiance under the overhead daylight fluorescent lamp phototherapy did not change with the increasing humidity. However, above 90% humidity, when water vapour inside the incubator was so saturated to the point of totally condensing in the incubator walls, the measured irradiance decreased 15% of the initial values with the blue LED phototherapy and 45% with the halogen spotlight phototherapy. Highly humidified incubators are frequently used to treat very low birthweight infants. Health professionals should be aware that mist and water condensation inside an incubator may significantly reduce the efficacy of treatment.

Evaluation of window-tinting films for sunlight phototherapy.

PubMed

Vreman, Hendrik J; Slusher, Tina M; Wong, Ronald J; Schulz, Stephanie; Olusanya, Bolajoko O; Stevenson, David K

2013-12-01

We evaluated nine semi-transparent plastic window-tinting films for their ability to block ultraviolet A (UVA) and infrared (IR) radiation and transmit therapeutic blue light (400-520 nm) for treating jaundiced newborns. For indoor testing, three light sources (TL/52 special blue fluorescent, Black Light UVA and IR heat lamps) were positioned above each film and measured successively using a thermocouple thermometer, UVA radiometer and blue light irradiance meter, placed below each film. For outdoor testing, the same setup was used with the sun at zenith and a cloudless sky. Compared with unfiltered radiation, blue light transmission through films ranged from 24 to 83%, UVA transmission was 0.1-7.1% and reductions in IR heat were 6-12°C and 5-10°C for heat lamp and sun, respectively. The data suggest that most of the relatively low-cost window-tinting films tested can effectively reduce sunlight UV and IR and offer a range of significant attenuations of therapeutic blue light.

Correspondence between training load executed by volleyball players and the one observed by coaches.

PubMed

Rodríguez-Marroyo, Jose A; Medina, Javier; García-López, Juan; García-Tormo, José V; Foster, Carl

2014-06-01

The main aim of this study was to compare the training load (TL) executed by volleyball players with that observed by coaches. Second, we analyzed the influence of the coaches' experience in the estimated TL. Twelve female volleyball players and 4 male coaches participated in this study. During a period of 15 weeks, physical (PT) and technical-tactical training sessions and matches were monitored. In each session, the session rating of perceived exertion (sRPE) was recorded to analyze the players' exercise intensity and TL(RP)E. Coaches were present in all sessions and rated their estimate of sRPE at the same time as the players to calculate the coaches' TL(RPE). Both players' and coaches' mean sRPE (4.0 ± 1.1, 3.7 ± 1.1, and 3.8 ± 1.0 in players and expert and beginning coaches, respectively) and TLRPE (380.1 ± 106.8, 358.3 ± 110.5, and 359.7 ± 108.0 in players and expert and beginning coaches, respectively) were similar. However, a higher (p < 0.01) sRPE and TL(RPE) were observed in the players during PT. In general, the weekly TL(RPE) variation over the course of this study was similar in players and coaches. The players' sRPE and TL(RPE) were correlated (p < 0.01) with expert and beginner coaches' RPE (r = 0.70 and 0.72, respectively) and TL(RPE) (r = 0.75 and 0.76, respectively). In conclusion, the present findings show the correspondence between players' and coaches' sRPE and TL(RPE) regardless of their experience. Hence, coaches' TL(RPE) could be a useful and practical method to monitor and control the TL and other derived parameters in an easy way during volleyball.

Evaluation of the UVB-screening capacity and restorative effects exerted by farnesol gel on UVB-caused sunburn.

PubMed

Wu, Guan Xuan; Huang, Han Hsiang; Chang, Huoy Rou; Kuo, Shyh Ming

2018-04-01

Farnesol, a natural 15-carbon organic compound, has various microbiological and cellular activities. It has been found to exert apoptosis-inducing effects against carcinoma cells as well as antiallergic and anti-inflammatory effects in vivo. In the current study, a series of formulations composed of various concentrations of hydroxypropyl methylcellulose (HPMC) with the addition of hyaluronan (HA) and xanthan gum (XG) was designed to evaluate the UVB-screening and H 2 O 2 -eliminating effects of farnesol in normal fibroblasts. Farnesol at 0.005, 0.0075, and 0.01% exhibited significant capacity for H 2 O 2 scavenging; at 0.0025%, it showed insignificant effects. Under 120-min UVB exposure, screening with plural gel composed of 0.0025% farnesol, 0.5% HA, and 0.5% XG containing 1.5% or 2% HPMC retained normal fibroblast viability. After 60-min exposure to UVB, screening with plural gel composed of farnesol, HA, XG, and 0.5%, 1.0%, 1.5%, or 2% HPMC decreased the ratio of the G1 phase and increased ratio of the S phase in comparison with the accumulated cell cycle of the normal fibroblasts without screening. The gel with 2% HPMC displayed the strongest cell cycle-reversal ability. In vivo histopathological results showed that the prepared plural gels with 0.5% or 2% HPMC and farnesol, HA, and XG had greater antiphotoaging and reparative effects against UVB-induced changes and damage in the skin. In conclusion, the current in vitro and in vivo results demonstrated that the prepared plural composed of 0.0025% farnesol, 0.5% HA, 0.5% XG, and 2% HPMC possessed the greatest UVB-screening capacity and the strongest restorative effects on UVB-induced sunburned skin. © 2018 Wiley Periodicals, Inc.

Total oxidant/antioxidant status in jaundiced newborns before and after phototherapy.

PubMed

Aycicek, Ali; Erel, Ozcan

2007-01-01

To assess the effect of phototherapy on serum oxidant and antioxidant status in hyperbilirubinemic full-term newborns. Thirty-four full-term infants from 3 to 10 days of age exposed to phototherapy were studied. The serum antioxidant status was assessed by measuring the total antioxidant capacity (TAC) and individual antioxidant components: vitamin C, uric acid, albumin, thiol contents and total bilirubin. The oxidant status was assessed by determining the total oxidant status (TOS), oxidative stress index (OSI) and individual oxidant components: malondialdehyde (MDA), and lipid hydroperoxide levels. Vitamin C, uric acid, total bilirubin and MDA concentration were significantly lower, whereas serum TOS, lipid hydroperoxide and OSI levels were significantly higher after phototherapy (p < 0.05). There were significant positive correlations between serum total bilirubin and MDA (r = 0.434, p = 0.001). Although the MDA level was reduced after phototherapy, phototherapy has a negative impact on numerous parts of the oxidant/antioxidant defense system in jaundiced full-term newborns, exposing them to potential oxidative stress.

Neonatal blue-light phototherapy does not increase nevus count in 9-year-old children.

PubMed

Mahé, Emmanuel; Beauchet, Alain; Aegerter, Philippe; Saiag, Philippe

2009-05-01

One of the most important risk factors for melanoma is the number of acquired common and atypical nevi in childhood. The role played by neonatal blue-light phototherapy in the increasing incidence of common and atypical melanocytic nevi in childhood or adolescence has been discussed recently with discordant results. We designed a multicenter study to assess the effects of neonatal blue-light phototherapy on nevus count in a cohort of 9-year-old children. We counted back and arm nevi as a function of size in 828 children included in a French photoprotection educational campaign. History of neonatal phototherapy, phototype, skin, hair and eye color, and sunburn were assessed through questionnaires to which both parents and children responded, and a nevus count was performed by trained nurses blinded to phototherapy history. Mean nevus count was 16.7 per child. Twenty-two percent of the children had received neonatal blue-light phototherapy. Neonatal phototherapy had no effect on the nevus count irrespective of nevi location, nevi size, or phototype of the children. A light phototype, skin, and hair color; blue/green eyes; and history of sunburn were closely correlated with an increase in nevus count. This study found no evidence for a major role of blue-light phototherapy on nevus count in 9-year-old children. It underlines the dominant effect of phototype characteristics and history of sunburn in childhood on the early development of melanocytic nevi.

Effect of phototherapy on shear bond strength of resin cements to zirconia ceramics: a systematic review and meta-analysis of in-vitro studies.

PubMed

Al-Aali, Khulud Abdulrahman

2018-05-11

The present study systematically reviewed the literature to investigate the effect of phototherapy on the shear bond strength (SBS) of resin cement to zirconia ceramic. electronic databases including MEDLINE (PubMed), ISI Web of Science, Scopus, ScIELO, LILACS and EMBASE until April 2018. The addressed focused question was: Does phototherapy increase the SBS of resin cement to zirconia ceramics?" A total of 8 in-vitro studies were included in the qualitative and quantitative analysis. The mean SBS for phototherapy ranged from 4.1 to 18.95 MPa while mean SBS for sandblasted zirconia-composite specimens ranged from 3.98 to 23.35 MPa in the included studies. Qualitative analysis showed 3 studies favoured application of phototherapy in significantly increasing SBS, while 4 studies indicated sandblasting showed significantly greater SBS of resin cement to zirconia ceramics. Considering the effects of phototherapy, significant heterogeneity for SBS (Q value = 136.37, p<0.0001, I 2  = 94.87%) was noticed among both the groups. The overall mean difference for SBS (SMD = -0.59, 95% CI = -1.99 to -0.80, p = 0.402) was not significant between phototherapy and sandblast (control) groups. Whether the effect of phototherapy on increasing the SBS of resin cement to zirconia ceramic is debatable. Further in-vitro studies should be performed in order to obtain strong conclusions. Copyright © 2018. Published by Elsevier B.V.

Inhibition of UV-B induced apoptosis in corneal epithelial cells by potassium channel modulators.

PubMed

Ubels, John L; Schotanus, Mark P; Bardolph, Susan L; Haarsma, Loren D; Koetje, Leah R; Louters, Julienne R

2010-02-01

The goal of this study was to determine whether prevention of K(+) loss can protect human corneal-limbal epithelial (HCLE) cells from UV-B induced apoptosis. Immunostaining for activated caspase-3 of HCLE cells exposed to 150-200 mJ/cm(2) UV-B demonstrated induction of apoptosis 6 h after exposure. The number of apoptotic cells was decreased by incubation in medium with 25 or 100 mM K(+). If this protection is due to a reduction of UV-induced K(+) loss then K(+) channel blockers should also protect HCLE cells from UV-B. Caspase-8 activity induced by exposure to UV-B at 150 mJ/cm(2) was significantly reduced when the cells were incubated in 0.3 microM BDS-I or 0.05-1 mM quinidine. Caspase-3 was also activated by UV-B and a reduction in activity was observed after incubation in 0.1-0.3 microM BDS-I and 0.1-1 mM quinidine. Induction of DNA fragmentation, as measured by the TUNEL assay, was decreased by treatment with 0.3 microM BDS-I and 0.01-0.05 mM quinidine. Patch-clamp recording showed activation of K(+) channels after exposure to UV-B and a decrease in outward K(+) current was observed following application of BDS-I. Quinidine did not block K(+) currents in HCLE cells, suggesting that the protective effect of quinidine occurs by a mechanism other than via K(+) channels. The effect of the K(+) channel blocker BDS-1 on HCLE cells exposed to UV-B confirms that preventing K(+) efflux protects corneal epithelial cells from apoptosis. This suggests the elevated [K(+)] in tears may protect the corneal epithelium from effects of ambient UV-B. Copyright 2009 Elsevier Ltd. All rights reserved.

[Newborn children under phototherapy: the mother's perception].

PubMed

Campos, Antonia do Carmo Soares; Cardoso, Maria Vera Lúcia Moreira Leitão

2004-01-01

Since 1958, phototherapy has been used as a method to cure jaundice, which is still an important disease in newborn children. Supported by a phenomenological and qualitative approach, this study aims to investigate the mothers' perception of the phototherapy treatment their children are submitted to. Research subjects were ten mothers of newborns under phototherapy treatment at the Neonatological Hospitalization Unit of a public maternity in Fortaleza-CE, Brazil. Data were collected between May and July 2002. We used group meetings with the mothers as suggested by Carl Rogers. Discourse was organized into categories according to Bardin, which revealed themes that were analyzed in view of Paterson's and Zderad's humanistic nursing theory, as follows: mothers' knowledge on phototherapy and concerns about the treatment. We concluded that the analyzed mothers' major concern is related to the babies' vision.

Seasonal Variation in Solar Ultra Violet Radiation and Early Mortality in Extremely Preterm Infants.

PubMed

Salas, Ariel A; Smith, Kelly A; Rodgers, Mackenzie D; Phillips, Vivien; Ambalavanan, Namasivayam

2015-11-01

Vitamin D production during pregnancy promotes fetal lung development, a major determinant of infant survival after preterm birth. Because vitamin D synthesis in humans is regulated by solar ultraviolet B (UVB) radiation, we hypothesized that seasonal variation in solar UVB doses during fetal development would be associated with variation in neonatal mortality rates. This cohort study included infants born alive with gestational age (GA) between 23 and 28 weeks gestation admitted to a neonatal unit between 1996 and 2010. Three infant cohort groups were defined according to increasing intensities of solar UVB doses at 17 and 22 weeks gestation. The primary outcome was death during the first 28 days after birth. Outcome data of 2,319 infants were analyzed. Mean birth weight was 830 ± 230 g and median gestational age was 26 weeks. Mortality rates were significantly different across groups (p = 0.04). High-intensity solar UVB doses were associated with lower mortality when compared with normal intensity solar UVB doses (hazard ratio: 0.70; 95% confidence interval: 0.54-0.91; p = 0.01). High-intensity solar UVB doses during fetal development seem to be associated with risk reduction of early mortality in preterm infants. Prospective studies are needed to validate these preliminary findings. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

The Timing Activities of the National Time and Frequency Standard Laboratory of the Telecommunication Laboratories, CHT Co. Ltd., Taiwan

DTIC Science & Technology

2009-11-01

Way Satellite Time and Frequency Transfer ( TWSTFT ). To meet future needs of precision, accuracy, and robustness for UTC (TL), TL rebuilt the air...TWO-WAY SATELLITE TIME TRANSFER TL maintains three earth stations for TWSTFT experiments, as listed on Table 1. The TL01 station is for the...Asia-Pacific TWSTFT links. All TWSTFT measurements in this area are performed simultaneously by using the eight-receive-channel NICT modems. Hourly

A Randomized Trial of Phototherapy with Filtered Sunlight in African Neonates.

PubMed

Slusher, Tina M; Olusanya, Bolajoko O; Vreman, Hendrik J; Brearley, Ann M; Vaucher, Yvonne E; Lund, Troy C; Wong, Ronald J; Emokpae, Abieyuwa A; Stevenson, David K

2015-09-17

Sequelae of severe neonatal hyperbilirubinemia constitute a substantial disease burden in areas where effective conventional phototherapy is unavailable. We previously found that the use of filtered sunlight for the purpose of phototherapy is a safe and efficacious method for reducing total bilirubin. However, its relative safety and efficacy as compared with conventional phototherapy are unknown. We conducted a randomized, controlled noninferiority trial in which filtered sunlight was compared with conventional phototherapy for the treatment of hyperbilirubinemia in term and late-preterm neonates in a large, urban Nigerian maternity hospital. The primary end point was efficacy, which was defined as a rate of increase in total serum bilirubin of less than 0.2 mg per deciliter per hour for infants up to 72 hours of age or a decrease in total serum bilirubin for infants older than 72 hours of age who received at least 5 hours of phototherapy; we prespecified a noninferiority margin of 10% for the difference in efficacy rates between groups. The need for an exchange transfusion was a secondary end point. We also assessed safety, which was defined as the absence of the need to withdraw therapy because of hyperthermia, hypothermia, dehydration, or sunburn. We enrolled 447 infants and randomly assigned 224 to filtered sunlight and 223 to conventional phototherapy. Filtered sunlight was efficacious on 93% of treatment days that could be evaluated, as compared with 90% for conventional phototherapy, and had a higher mean level of irradiance (40 vs. 17 μW per square centimeter per nanometer, P<0.001). Temperatures higher than 38.0°C occurred in 5% of the infants receiving filtered sunlight and in 1% of those receiving conventional phototherapy (P<0.001), but no infant met the criteria for withdrawal from the study for reasons of safety or required an exchange transfusion. Filtered sunlight was noninferior to conventional phototherapy for the treatment of neonatal hyperbilirubinemia and did not result in any study withdrawals for reasons of safety. (Funded by the Thrasher Research Fund, Salt Lake City, and the National Center for Advancing Translational Sciences of the National Institutes of Health; Clinical Trials.gov number, NCT01434810.).

The flavonoid, fisetin, inhibits UV radiation-induced oxidative stress and the activation of NF-kappaB and MAPK signaling in human lens epithelial cells.

PubMed

Yao, Ke; Zhang, Li; Zhang, Yidong; Ye, PanPan; Zhu, Ning

2008-01-01

Ultraviolet (UV) radiation-induced oxidative stress plays a significant role in the progression of cataracts. This study investigated the photoprotective effect of fisetin on UV radiation-induced oxidative stress in human lens epithelial cells and the possible molecular mechanism involved. SRA01/04 cells exposed to different doses of ultraviolet B (UVB) were cultured with various concentrations of fisetin and subsequently monitored for cell viability by the 4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT) assay. The effect of fisetin on the generation of reactive oxygen species (ROS) of SRA01/04 cells was determined by flow cytometry. Translocation of nuclear factor kappa-B (NF-kappaB) was examined by immunocytochemistry. Expression of NF-kappaB/P65, inhibiter kappa B (IkappaB), and mitogen activated protein kinase (MAPK) proteins were measured by western blot. Treatment of SRA01/04 cells with fisetin inhibited UVB-induced cell death and the generation of ROS. Fisetin inhibited UVB-induced activation and translocation of NF-kappaB/p65, which was mediated through an inhibition of the degradation and activation of IkappaB. Fisetin also inhibited UVB-induced phosphorylation of the p38 and c-Jun N-terminal kinase (JNK) proteins of the MAPK family at various time points studied. The flavonoid, fisetin, could be useful in attenuation of UV radiation-induced oxidative stress and the activation of NF-kappaB and MAPK signaling in human lens epithelial cells, which suggests that fisetin has a potential protective effect against cataractogenesis.

New scanner fiber optic delivery system for laser phototherapy in the treatment of neonatal jaundice

NASA Astrophysics Data System (ADS)

Hamza, Mostafa; Hamza, Mohammad S. E.

1995-05-01

The authors have introduced laser phototherapy for the treatment of neonatal jaundice. Clinical trials have demonstrated its high efficacy compared to the conventionally used fluorescent phototherapy. In this paper a new modification to laser irradiation in phototherapy can be achieved by scanning the laser output beam in the selected wavelength of irradiation (488 nm) through a fiberoptic bundle which irradiate the skin of the baby. Scanning of the laser beam provides intermittent irradiation at high frequency, which can provide the same therapeutic efficacy with almost half the power of laser irradiation.

A comparison of methods to quantify the in-season training load of professional soccer players.

PubMed

Scott, Brendan R; Lockie, Robert G; Knight, Timothy J; Clark, Andrew C; Janse de Jonge, Xanne A K

2013-03-01

To compare various measures of training load (TL) derived from physiological (heart rate [HR]), perceptual (rating of perceived exertion [RPE]), and physical (global positioning system [GPS] and accelerometer) data during in-season field-based training for professional soccer. Fifteen professional male soccer players (age 24.9 ± 5.4 y, body mass 77.6 ± 7.5 kg, height 181.1 ± 6.9 cm) were assessed in-season across 97 individual training sessions. Measures of external TL (total distance [TD], the volume of low-speed activity [LSA; <14.4 km/h], high-speed running [HSR; >14.4 km/h], very high-speed running [VHSR; >19.8 km/h], and player load), HR and session-RPE (sRPE) scores were recorded. Internal TL scores (HR-based and sRPE-based) were calculated, and their relationships with measures of external TL were quantified using Pearson product-moment correlations. Physical measures of TD, LSA volume, and player load provided large, significant (r = .71-.84; P < .01) correlations with the HR-based and sRPE-based methods. Volume of HSR and VHSR provided moderate to large, significant (r = .40-.67; P < .01) correlations with measures of internal TL. While the volume of HSR and VHSR provided significant relationships with internal TL, physical-performance measures of TD, LSA volume, and player load appear to be more acceptable indicators of external TL, due to the greater magnitude of their correlations with measures of internal TL.

Depressive symptoms, depression, and the effect of biologic therapy among patients in Psoriasis Longitudinal Assessment and Registry (PSOLAR).

PubMed

Strober, Bruce; Gooderham, Melinda; de Jong, Elke M G J; Kimball, Alexa B; Langley, Richard G; Lakdawala, Nikita; Goyal, Kavitha; Lawson, Fabio; Langholff, Wayne; Hopkins, Lori; Fakharzadeh, Steve; Srivastava, Bhaskar; Menter, Alan

2018-01-01

Patients with psoriasis are at an increased risk for depression. However, the impact of treatment on this risk is unclear. Evaluate the incidence and impact of treatment on depression among patients with moderate-to-severe psoriasis. We defined a study population within the Psoriasis Longitudinal Assessment and Registry and measured the incidence of depressive symptoms (Hospital Anxiety and Depression Scale-Depression score ≥8) and adverse events (AEs) of depression within cohorts receiving biologics, conventional systemic therapies, or phototherapy. Patients were evaluated at approximately 6-month intervals. Multivariate modeling determined the impact of treatment on risk. The incidence rates of depressive symptoms were 3.01 per 100 patient-years (PYs) (95% confidence interval [CI], 2.73-3.32), 5.85 per 100 PYs (95% CI, 4.29-7.97), and 5.70 per 100 PYs (95% CI, 4.58-7.10) for biologics, phototherapy, and conventional therapy, respectively. Compared with conventional therapy, biologics reduced the risk for depressive symptoms (hazard ratio, 0.76; 95% CI, 0.59-0.98), whereas phototherapy did not (hazard ratio, 1.05; 95% CI, 0.71-1.54). The incidence rates for AEs of depression were 0.21 per 100 PYs (95% CI, 0.15-0.31) for biologics, 0.55 per 100 PYs (95% CI, 0.21-1.47) for phototherapy, and 0.14 per 100 PYs (95% CI, 0.03-0.55) for conventional therapy; the fact that there were too few events (37 AEs) precluded modeling. Incomplete capture of depression and confounders in the patients on registry. Compared with conventional therapy, biologics appear to be associated with a lower incidence of depressive symptoms among patients with psoriasis. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Phototherapy with blue and green mixed-light is as effective against unconjugated jaundice as blue light and reduces oxidative stress in the Gunn rat model.

PubMed

Uchida, Yumiko; Morimoto, Yukihiro; Uchiike, Takao; Kamamoto, Tomoyuki; Hayashi, Tamaki; Arai, Ikuyo; Nishikubo, Toshiya; Takahashi, Yukihiro

2015-07-01

Phototherapy using blue light-emitting diodes (LED) is effective against neonatal jaundice. However, green light phototherapy also reduces unconjugated jaundice. We aimed to determine whether mixed blue and green light can relieve jaundice with minimal oxidative stress as effectively as either blue or green light alone in a rat model. Gunn rats were exposed to phototherapy with blue (420-520 nm), filtered blue (FB; 440-520 nm without<440-nm wavelengths, FB50 (half the irradiance of filtered blue), mixed (filtered 50% blue and 50% green), and green (490-590 nm) LED irradiation for 24h. The effects of phototherapy are expressed as ratios of serum total (TB) and unbound (UB) bilirubin before and after exposure to each LED. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured by HPLC before and after exposure to each LED to determine photo-oxidative stress. Values < 1.00 indicate effective phototherapy. The ratios of TB and UB were decreased to 0.85, 0.89, 1.07, 0.90, and 1.04, and 0.85, 0.94, 0.93, 0.89, and 1.09 after exposure to blue, filtered blue, FB50, and filtered blue mixed with green LED, respectively. In contrast, urinary 8-OHdG increased to 2.03, 1.25, 0.96, 1.36, 1.31, and 1.23 after exposure to blue, filtered blue, FB50, mixed, green LED, and control, indicating side-effects (> 1.00), respectively. Blue plus green phototherapy is as effective as blue phototherapy and it attenuates irradiation-induced oxidative stress. Combined blue and green spectra might be effective against neonatal hyperbilirubinemia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Phototherapy on Management of Creatine Kinase Activity in General Versus Localized Exercise: A Systematic Review and Meta-Analysis.

PubMed

Machado, Aryane Flauzino; Micheletti, Jéssica Kirsch; Lopes, Jaqueline Santos Silva; Vanderlei, Franciele Marques; Leal-Junior, Ernesto Cesar Pinto; Netto Junior, Jayme; Pastre, Carlos Marcelo

2018-06-21

The main focus of this systematic review was to determine the efficacy of phototherapy in the management of creatine kinase (CK) activity after exercise and furthermore to identify for which exercise model protocol phototherapy provides the best results. Meta-analysis comparing phototherapy with a control condition. The MEDLINE, EMBASE, SPORTDiscus, PEDro, and CENTRAL databases were searched from their earliest records to October 03, 2016. Data were pooled in a meta-analysis and described as standardized mean difference (SMD) with 95% confidence intervals (CIs) using a random effects model. Healthy subjects (no restrictions were applied, eg, age, sex, and exercise level). Phototherapy (low-level laser therapy and/or light-emitting diode therapy) before or after exercise and a placebo or control condition. Creatine kinase activity (no restriction to any analysis, eg, serum, plasma, or capillary blood). Fourteen studies were included for review. The results revealed that phototherapy has a more positive effect than control condition in management of CK activity [SMD = 0.77, 95% CI (0.32 to 1.22); P = 0.0007; I = 72%]. In exploratory analysis, the results showed that phototherapy was effective only in the exercise protocol with localized exercise with large effect size [localized exercise: SMD = 0.89, 95% CI (0.26 to 1.51); P = 0.0002; I = 76%; general exercise: SMD = 0.61, 95% CI (-0.05 to 1.26); P = 0.07; I = 67%]. The available evidence suggest that phototherapy has beneficial effects on the management of CK activity and demonstrate a possible relationship based on damage caused by exercise, providing a greater effect in studies that used localized exercise.

Effect of Phototherapy on the Reliability of Transcutaneous Bilirubin Devices in Term and Near-Term Infants: A Systematic Review and Meta-Analysis.

PubMed

Nagar, Gaurav; Vandermeer, Ben; Campbell, Sandy; Kumar, Manoj

2016-01-01

Transcutaneous bilirubin (TcB) devices are commonly used for screening of hyperbilirubinemia in term and near-term infants not exposed to phototherapy. However, the accuracy of TcB devices in infants exposed to phototherapy is unclear. To conduct a systematic review of studies comparing TcB devices with total serum bilirubin (TSB) in infants receiving phototherapy or in the postphototherapy phase. MEDLINE, EMBASE, Cochrane Library, CINAHL and Scopus databases (from inception to May 8, 2014) were searched. Additional citations were identified from the bibliography of selected articles and from the abstracts of conference proceedings. The studies were included if they compared TcB results with TSB in term and near-term infants during phototherapy or after discontinuation of phototherapy. Two reviewers independently assessed studies for inclusion, and discrepancies were resolved with consensus. Risk of bias was assessed using the QUADAS-2 tool. Fourteen studies were identified. The pooled estimates of correlation coefficients (r) during phototherapy were: covered sites 0.71 (95% CI 0.64-0.77, 11 studies), uncovered sites 0.65 (95% CI 0.55-0.74), 8 studies), forehead 0.70 (95% CI 0.64-0.75, 12 studies) and sternum 0.64 (95% CI 0.43-0.77, 5 studies). Two studies also provided results as Bland-Altman difference plots (mean TcB-TSB differences -29.2 and 30 µmol/l, respectively). The correlation coefficient improved marginally in the postphototherapy phase (r = 0.72, 95% CI 0.64-0.78, 4 studies). We found a moderate correlation between TcB and TSB during phototherapy with a marginal improvement in the postphototherapy phase. Further research is needed before the use of TcB devices can be recommended for these settings. © 2016 S. Karger AG, Basel.

Comparison of conventional phototherapy and phototherapy along with Kangaroo mother care on cutaneous bilirubin of neonates with physiological jaundice.

PubMed

Goudarzvand, Laleh; Dabirian, Akram; Nourian, Manijeh; Jafarimanesh, Hadi; Ranjbaran, Mehdi

2017-11-27

One of the adjuvant and desirable therapies is skin contact between mother and baby or Kangaroo mother care (KMC) that is a cheap, accessible, relaxing, noninvasive and easy method. This study aimed to compare the effect of conventional phototherapy method and phototherapy along with KMC on cutaneous bilirubin in neonates with physiological jaundice. In this randomized clinical trial, all infants with physiological jaundice who referred for phototherapy to Mofid Hospital of Shahid Beheshti University of Medical Sciences, Tehran, Iran were selected by convenience sampling based on inclusion criteria and were randomly assigned into two groups of conventional phototherapy (n = 35) and phototherapy along with KMC (n = 35). The results showed that there was a significant difference in the average volume of skin bilirubin before treatment with cutaneous bilirubin every 24 h after treatment (p < .001). This significant difference was present in both intervention and control groups. Although the average volume of skin bilirubin every 24 h after treatment was lower in the intervention group than the control group, this difference was not statistically significant (p = .236). Mean duration of hospitalization of infants in the intervention group was significantly lower than the control group (2.09 versus 3.03 d, p < .001). Although KMC along with phototherapy has a favorable effect on the reduction of cutaneous bilirubin in neonates with physiological jaundice, there are not significant differences in routine care. This may need to do KMC for a longer time (more than 1 h) which must be surveyed in the future studies. KMC was effective in reduction of the duration of hospitalization in jaundiced infants.

Risk of Autism Associated With Hyperbilirubinemia and Phototherapy.

PubMed

Wu, Yvonne W; Kuzniewicz, Michael W; Croen, Lisa; Walsh, Eileen M; McCulloch, Charles E; Newman, Thomas B

2016-10-01

Whether neonatal hyperbilirubinemia and/or phototherapy increase the risk of autism spectrum disorder (ASD) is unclear. We sought to quantify the risk of ASD associated with elevated total serum bilirubin (TSB) levels and with phototherapy. In a retrospective cohort study of 525 409 infants born at ≥35 weeks' gestation in 15 Kaiser Permanente Northern California (KPNC) hospitals, 1995-2011, we obtained all TSB levels and determined which infants received phototherapy. From the KPNC Autism Registry, we identified patients with ASD diagnosed at a KPNC Autism Center, by a clinical specialist, or by a pediatrician. We calculated Cox proportional hazard ratios (HRs) for time to diagnosis of ASD, adjusting for confounding factors. Among infants in the birth cohort, 2% had at least 1 TSB level ≥20 mg/dL, and 8% received phototherapy. The rate of ASD was 13 per 1000 births. Crude analyses revealed an association between TSB ≥20 and ASD (relative risk: 1.4; 95% confidence interval [CI]: 1.1-1.6), and between phototherapy and ASD (relative risk: 1.7; 95% CI: 1.5-1.8). After adjusting for confounders, TSB ≥20 (HR: 1.09; 95% CI: 0.89-1.35) and phototherapy (HR: 1.10; 95% CI: 0.98-1.24) were no longer significantly associated with ASD. Independent risk factors for ASD included maternal and paternal age; maternal and paternal higher education; male sex; birth weight <2500 g or ≥4200 g; and later year of birth. After adjustment for the effects of sociodemographic factors and birth weight, neither hyperbilirubinemia nor phototherapy was an independent risk factor for ASD. Copyright © 2016 by the American Academy of Pediatrics.

Eicosapentaenoic acid and docosahexaenoic acid reduce UVB- and TNF-alpha-induced IL-8 secretion in keratinocytes and UVB-induced IL-8 in fibroblasts.

PubMed

Storey, Amy; McArdle, Frank; Friedmann, Peter S; Jackson, Malcolm J; Rhodes, Lesley E

2005-01-01

Omega-3 polyunsaturated fatty acids (n-3 PUFA) inhibit ultraviolet B (UVB)-induced inflammation and other inflammatory states, in vivo. We examined whether this may be mediated by modulation of interleukin (IL)-8, a chemokine pivotal to skin inflammation induced by UVB, in epidermal and dermal cells. We also explored the ability of n-3 PUFA to protect against tumor necrosis factor (TNF)-alpha induction of IL-8, and assessed relative potencies of the principal dietary n-3 PUFA, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Pre-supplementation, both HaCaT keratinocyte and CCD922SK fibroblast cell lines showed dose-responses for UVB-induced IL-8 release (p<0.001), assessed 48 h post-irradiation. Cells were supplemented with > or =90% purified EPA, DHA, oleic acid (OA) or vehicle control, for 4.5 d. EPA and DHA supplements were bioavailable to keratinocytes and fibroblasts. In keratinocytes, EPA and DHA were shown to reduce basal secretion of IL-8 by 66% and 63%, respectively (p<0.05), and UVB-induced levels by 66% and 65% at 48 h after 100 mJ per cm2, respectively, (p<0.01). A similar pattern occurred in fibroblasts, whereas OA had no influence on IL-8 release in either cell line. In addition, TNF-alpha-induced IL-8 secretion by keratinocytes was reduced by 54% and 42%, respectively, by EPA and DHA (p<0.001). Hence both n-3 PUFA inhibit production of UVB- and TNF-alpha-induced IL-8 in skin cells; this may be important in the photoprotective and other anti-inflammatory effects conferred by these agents.

The response of antioxidant systems in Nostoc sphaeroides against UV-B radiation and the protective effects of exogenous antioxidants

NASA Astrophysics Data System (ADS)

Wang, Gaohong; Hu, Chunxiang; Li, Dunhai; Zhang, Delu; Li, Xiaoyan; Chen, Kun; Liu, Yongding

UV radiation is one of many harmful factors found in space that are detrimental to organisms on earth in space exploration. In the present work, we examined the role of antioxidant system in Nostoc sphaeroides Kütz (Cyanobacterium) and the effects of exogenously applied antioxidant molecules on its photosynthetic rate under UV-B radiation. It was found that UV-B radiation promoted the activity of antioxidant system to protect photosystem II (PSII) and exogenously applied antioxidant: sodium nitroprusside (SNP) and N-acetylcysteine (NAC) had an obvious protection on PSII activity under UV-B radiation. The activity of superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), peroxidase (POD, EC 1.11.1.7) and content of MDA (malondialdehyde) and ASC (ascorbate) were improved by 0.5 mM and 1 mM SNP, but 0.1 mM SNP decreased the activity of antioxidant system. Addition of exogenous NAC decreased the activity of SOD, POD, CAT and the content MDA and ASC. In contrast, exogenously applied NAC increased GSH content. The results suggest that exogenous SNP and NAC may protect algae by different mechanisms: SNP may play double roles as both sources of reactive free radicals as well as ROS scavengers in mediating the protective role of PSII on algae under UV-B radiation. On the other hand, NAC functions as an antioxidant or precursor of glutathione, which could protect PSII directly from UV-B radiation.

Octylphenol and UV-B radiation alter larval development and hypothalamic gene expression in the leopard frog (Rana pipiens).

PubMed Central

Crump, Douglas; Lean, David; Trudeau, Vance L

2002-01-01

We assessed octylphenol (OP), an estrogenic endocrine-disrupting chemical, and UV-B radiation, a known stressor in amphibian development, for their effects on hypothalamic gene expression and premetamorphic development in the leopard frog Rana pipiens. Newly hatched tadpoles were exposed for 10 days to OP alone at two different dose levels; to subambient UV-B radiation alone; and to two combinations of OP and UV-B. Control animals were exposed to ethanol vehicle (0.01%) exposure, a subset of tadpoles from each treatment group was raised to metamorphosis to assess differences in body weight and time required for hindlimb emergence. Tadpoles from one of the OP/UV-B combination groups had greater body weight and earlier hindlimb emergence (p < 0.05), but neither OP nor UV-B alone produced significant changes in body weight or hindlimb emergence, indicating a potential mechanism of interaction between OP and UV-B. We hypothesized that the developing hypothalamus might be a potential environmental sensor for neurotoxicologic studies because of its role in the endocrine control of metamorphosis. We used a differential display strategy to identify candidate genes differentially expressed in the hypothalamic region of the exposed tadpoles. Homology cloning was performed to obtain R. pipiens glutamate decarboxylases--GAD65 and GAD67, enzymes involved in the synthesis of the neurotransmitter gamma-aminobutyric acid (GABA). cDNA expression profiles revealed that OP and UV-B affected the levels of several candidate transcripts in tadpole (i.e., Nck, Ash, and phospholipase C gamma-binding protein 4 and brain angiogenesis inhibitor-3) and metamorph (i.e., GAD67, cytochrome C oxidase, and brain angiogenesis inhibitor-2 and -3) brains. This study represents a novel approach in toxicology that combines physiologic and molecular end points and indicates that levels of OP commonly found in the environment and subambient levels of UV-B alter the expression of important hypothalamic genes and disrupt tadpole growth patterns. PMID:11882479

Octylphenol and UV-B radiation alter larval development and hypothalamic gene expression in the leopard frog (Rana pipiens).

PubMed

Crump, Douglas; Lean, David; Trudeau, Vance L

2002-03-01

We assessed octylphenol (OP), an estrogenic endocrine-disrupting chemical, and UV-B radiation, a known stressor in amphibian development, for their effects on hypothalamic gene expression and premetamorphic development in the leopard frog Rana pipiens. Newly hatched tadpoles were exposed for 10 days to OP alone at two different dose levels; to subambient UV-B radiation alone; and to two combinations of OP and UV-B. Control animals were exposed to ethanol vehicle (0.01%) exposure, a subset of tadpoles from each treatment group was raised to metamorphosis to assess differences in body weight and time required for hindlimb emergence. Tadpoles from one of the OP/UV-B combination groups had greater body weight and earlier hindlimb emergence (p < 0.05), but neither OP nor UV-B alone produced significant changes in body weight or hindlimb emergence, indicating a potential mechanism of interaction between OP and UV-B. We hypothesized that the developing hypothalamus might be a potential environmental sensor for neurotoxicologic studies because of its role in the endocrine control of metamorphosis. We used a differential display strategy to identify candidate genes differentially expressed in the hypothalamic region of the exposed tadpoles. Homology cloning was performed to obtain R. pipiens glutamate decarboxylases--GAD65 and GAD67, enzymes involved in the synthesis of the neurotransmitter gamma-aminobutyric acid (GABA). cDNA expression profiles revealed that OP and UV-B affected the levels of several candidate transcripts in tadpole (i.e., Nck, Ash, and phospholipase C gamma-binding protein 4 and brain angiogenesis inhibitor-3) and metamorph (i.e., GAD67, cytochrome C oxidase, and brain angiogenesis inhibitor-2 and -3) brains. This study represents a novel approach in toxicology that combines physiologic and molecular end points and indicates that levels of OP commonly found in the environment and subambient levels of UV-B alter the expression of important hypothalamic genes and disrupt tadpole growth patterns.

High-dose ascorbic acid decreases cholesterolemic factors of an atherogenic diet in guinea pigs.

PubMed

Filis, Konstantinos; Anastassopoulou, Aikaterini; Sigala, Fragiska; Theodorou, Dimitrios; Manouras, Andreas; Leandros, Emanouel; Sigalas, Panagiotis; Hepp, Wolfgang; Bramis, John

2007-03-01

The study evaluates the effect of a high supplemental dose of ascorbic acid (AA) on plasma concentrations of total cholesterol (TC), triglycerides (TG), total lipids (TL), and lipoprotein fractions high-density, very-low-density-, and low-density lipoprotein (HDL, VLDL, LDL) in guinea pigs fed with atherogenic diet. Group I consisted of 5 normally fed guinea pigs plus a low dose of AA (1 mg/100 g/day), group II consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a low dose of AA (1 mg/100 g/day), and group III consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a high dose of AA (30 mg/100 g/day). Cholesterolemic factors concentrations were determined after nine weeks. Concentrations of TC, TG, TL, LDL, and VLDL were increased in group II compared to group I (p < 0.01 for all differences). Supplementation with a high dose of AA resulted in decreased concentrations of TC (p < 0.01), TG (p < 0.01), TL (p < 0.01), and LDL (p < 0.01) in group III compared to group II. Additionally, concentration of HDL was increased in group III compared to group II (p < 0.01). High-dose AA supplementation to an atherogenic diet decreases concentrations of TC, TG, TL, and LDL and increases concentration of HDL compared to low-dose AA.

Amelioration of ultraviolet-induced photokeratitis in mice treated with astaxanthin eye drops.

PubMed

Lennikov, Anton; Kitaichi, Nobuyoshi; Fukase, Risa; Murata, Miyuki; Noda, Kousuke; Ando, Ryo; Ohguchi, Takeshi; Kawakita, Tetsuya; Ohno, Shigeaki; Ishida, Susumu

2012-01-01

Ultraviolet (UV) acts as low-dose ionizing radiation. Acute UVB exposure causes photokeratitis and induces apoptosis in corneal cells. Astaxanthin (AST) is a carotenoid, present in seafood, that has potential clinical applications due to its high antioxidant activity. In the present study, we examined whether topical administration of AST has preventive and therapeutic effects on UV-photokeratitis in mice. C57BL/6 mice were administered with AST diluted in polyethylene glycol (PEG) in instillation form (15 μl) to the right eye. Left eyes were given vehicle alone as controls. Immediately after the instillation, the mice, under anesthesia, were irradiated with UVB at a dose of 400 mJ/cm². Eyeballs were collected 24 h after irradiation and stained with H&E and TUNEL. In an in vitro study, mouse corneal epithelial (TKE2) cells were cultured with AST before UV exposure to quantify the UV-derived cytotoxicity. UVB exposure induced cell death and thinning of the corneal epithelium. However, the epithelium was morphologically well preserved after irradiation in AST-treated corneas. Irradiated corneal epithelium was significantly thicker in eyes treated with AST eye drops, compared to those treated with vehicles (p<0.01), in a doses dependent manner. Significantly fewer apoptotic cells were observed in AST-treated eyes than controls after irradiation (p<0.01). AST also reduced oxidative stress in irradiated corneas. The in vitro study showed less cytotoxicity of TKE2 cells in AST-treated cultures after UVB-irradiation (p<0.01). The cytoprotective effect increased with the dose of AST. Topical AST administration may be a candidate treatment to limit the damages by UV irradiation with wide clinical applications.

Medical laboratory technician professional pathologies: a 2006-2016 literature review.

PubMed

Pougnet, Richard; Loddé, Brice; Uguen, Marie; Sawicki, Bénédicte; Pougnet, Laurence

2017-12-01

The trade of laboratory technician (TL) exposes to many risks to health, because of biological or chemical or physical exposures. But the TL occupation is constantly evolving, the techniques are constantly changing. The purpose of this article is to take stock of the occupational TL pathologies which were recently described in the literature. This is a literature review, based on Medline® and Scopus® medical databases, on publications between 01/01/2006 and 31/12/2016. The research was conducted in French and English. Only articles about TL in Hospital or Teaching Hospital were selected. Twenty-eight articles were studied. The main infectious pathology described was brucellosis and a case of meningitis was studied. The cutaneous allergies reported concerned sensitization to certain solvents. There was no allergy to latex. Musculoskeletal disorders (MSD) were studied in 4 articles. The main MSDs were low back pain and neck pain. Several articles have alerted on the occurrence of burnout syndrome (BO). However, no prevalence studies were conducted over the period studied. In conclusion, TL can present many occupational pathologies. Few articles studied the prevalence of MSD and BO.

Phototherapy for alopecia areata.

PubMed

Welsh, Oliverio

2016-01-01

Phototherapy is a useful therapeutic method for various skin diseases due to its modulatory effect on the cutaneous immune system. Alopecia areata is a dermatosis characterized by partial or complete hair loss. Collapse of the immune privilege of the hair follicle, which induces noncicatricial alopecia, is an important factor in its etiology. Several forms of phototherapy are used in dermatology. Copyright © 2016 Elsevier Inc. All rights reserved.

The Shubnikov-de Haas effect and thermoelectric properties of Tl-doped Sb{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kulbachinskii, V. A., E-mail: kulb@mig.phys.msu.ru; Kudryashov, A. A.; Kytin, V. G.

2015-06-15

The influence of doping with Tl on the Shubnikov-de Haas effect at T = 4.2 K in magnetic fields up to 38 T in p-Sb{sub 2−x}Tl{sub x}Te{sub 3} (x = 0, 0.005, 0.015, and 0.05) and n-Bi{sub 2−x}Tl{sub x}Se{sub 3} (x = 0, 0.01, 0.02, 0.04, and 0.06) single crystals is investigated. Extreme cross-sections of the Fermi surface in both materials decrease upon doping with Tl: the hole concentration decreases in Sb{sub 2−x}Tl{sub x}Te{sub 3} due to the donor effect of Tl and the electron concentration in n-Bi{sub 2−x}Tl{sub x}Se{sub 3} decreases due to the acceptor effect of Tl. Themore » temperature dependences of the Seebeck coefficient, electrical conductivity, thermal conductivity, and dimensionless thermoelectric figure of merit in a temperature range of 77–300 K are measured. The thermal conductivity and electrical conductivity decrease upon doping with Tl both in p-Sb{sub 2−x}Tl{sub x}Te{sub 3} and in n-Bi{sub 2−x}Tl{sub x}Se{sub 3}. The Seebeck coefficient increases in all compositions upon an increase in doping over the entire measured temperature range. The thermoelectric figure of merit increases upon doping with Tl.« less

Cerenkov radiation-induced phototherapy for depth-independent cancer treatment (Conference Presentation)

NASA Astrophysics Data System (ADS)

Akers, Walter J.; Achilefu, Samuel; Kotagiri, Nalinikanth

2017-02-01

Light emitted as the result of high-energy particle transport through biological tissues (Cerenkov radiation) can be exploited for noninvasive diagnostic imaging using high sensitivity scientific cameras. We have investigated the energy transfer potential of Cerenkov radiation, discovering a new phototherapeutic technique for treatment of localized and disseminated cancers. This technique, Cerenkov radiation-induced phototherapy (CRIT), like photodynamic therapy, requires the presence of both light and photosensitive agent together to induce cytotoxicity and effective cancer treatment. But unlike conventional phototherapy strategies in which tissue ablation or activation of photoactive molecules is limited to superficial structures, radiation-induced phototherapy enables phototherapy delivery to the tumor sites throughout the body. Titanium oxide nanoparticles, which produce cytotoxic reactive oxygen species upon irradiation with UV light, were targeted to tumor tissue by surface decoration with transferrin. Subsequent administration of tumor-avid radiotracer, 18-fluorodeoxyglucose (18FDG) provided localized UV light source via Cerenkov radiation. Treatment of tumor-bearing mice with the combination of Titanium nanoparticles and 18FDG resulted in effective reduction in tumor growth, while individual agents were not therapeutic. This new strategy in cancer therapy extends the reach of phototherapy beyond what was previously possible, with potential for treatment of cancer metastases and rescue from treatment resistance.

Calix[4]arene-bis(t-octylbenzo-18-crown-6) as an extraordinarily effective macrocyclic receptor for the univalent thallium cation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makrlik, Emanuel; Toman, Petr; Vanura, Petr

2013-01-01

From extraction experiments and -activity measurements, the exchange extraction constant corresponding to the equilibrium Tl+ (aq) + 1 Cs+ (org) 1 Tl+ (org) + Cs+ (aq) taking place in the two-phase water phenyltrifluoromethyl sulfone (abbrev. FS 13) system (1 = calix[4]arene-bis(t-octylbenzo-18-crown-6); aq = aqueous phase, org = FS 13 phase) was evaluated as log Kex (Tl+, 1 Cs+) = 1.7 0.1. Further, the extraordinarily high stability constant of the 1 Tl+ complex in FS 13 saturated with water was calculated for a temperature of 25 C: log org(1 Tl+) = 13.1 0.2. Finally, by using quantum mechanical DFT calculations, themore » most probable structure of the cationic complex species 1 Tl+ was derived. In the resulting 1 Tl+ complex, the central cation Tl+ is bound by eight bond interactions to six oxygen atoms from the respective 18-crown-6 moiety and to two carbons of the corresponding two benzene rings of the parent receptor 1 via cation interaction.« less

Transcutaneous bilirubin levels in newborns <35 weeks' gestation.

PubMed

Maisels, M J; Coffey, M P; Kring, E

2015-09-01

In infants <35 weeks' gestation, we sought to define the transcutaneous bilirubin (TcB) levels at which a total serum bilirubin (TSB) level suggesting the need for phototherapy is unlikely to occur and a TSB measurement can, therefore, be avoided. Nursing staff performed 896 TcB measurements within 1 h of a TSB on 225 neonates 26 0/7-34 6/7 weeks' postmenstrual age (PMA). Generalized linear models were fit with generalized estimating equations (GEEs) to model the probability of having a TSB level at or above the phototherapy initiation cutpoint as a function of the TcB; these methods allow for multiple tests per infant. The mean difference between TcB and TSB measurements was <1 mg dl(-1) for each PMA category. When the TcB was at least 3 mg dl(-1) below the TSB cutpoint for phototherapy, there was a ⩾98% probability that the TSB was not at, or above, the recommended phototherapy level. The single exception to this was a phototherapy level of 6 mg dl(-1) for infants of 28 0/7-29 6/7 weeks' PMA, where a TcB of 4 mg dl(-1) below the phototherapy level (ie a TcB ⩽2 mg dl(-1)) was necessary to achieve ⩾98% probability. Our data support the use of routine TcB screening for infants 28-34 6/7 weeks' gestation. TcB screening in the neonatal intensive care unit can identify infants who require a TSB to confirm or exclude the need for phototherapy.

Effect of thallium doping on the mobility of electrons in Bi{sub 2}Se{sub 3} and holes in Sb{sub 2}Te{sub 3}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kudryashov, A. A.; Kytin, V. G.; Lunin, R. A.

2016-07-15

The Shubnikov–de Haas effect and the Hall effect in n-Bi{sub 2–x}Tl{sub x}Se{sub 3} (x = 0, 0.01, 0.02, 0.04) and p-Sb{sub 2–x}Tl{sub x}Te{sub 3} (x = 0, 0.005, 0.015, 0.05) single crystals are studied. The carrier mobilities and their changes upon Tl doping are calculated by the Fourier spectra of oscillations. It is found shown that Tl doping decreases the electron concentration in n-Bi{sub 2–x}Tl{sub x}Se{sub 3} and increases the electron mobility. In p-Sb{sub 2–x}Tl{sub x}Te{sub 3}, both the hole concentration and mobility decrease upon Tl doping. The change in the crystal defect concentration, which leads to these effects, ismore » discussed.« less

Adiposity and insulin resistance correlate with telomere length in middle-aged Arabs: the influence of circulating adiponectin.

PubMed

Al-Attas, Omar S; Al-Daghri, Nasser M; Alokail, Majed S; Alfadda, Assim; Bamakhramah, Ahmed; Sabico, Shaun; Pritlove, Dave; Harte, Alison; Tripathi, Gyanendra; McTernan, Philip G; Kumar, Sudhesh; Chrousos, George

2010-10-01

Studies in obesity have implicated adipocytokines in the development of insulin resistance, which in turn may lead to accelerated aging. In this study, we determined associations of chromosomal telomere length (TL) to markers of obesity and insulin resistance in middle-aged adult male and female Arabs with and without diabetes mellitus type 2 (DMT2). One hundred and ninety-three non-diabetic and DMT2 subjects without complications (97 males and 96 females) participated in this cross-sectional study. Clinical data, as well as fasting blood samples, were collected. Serum glucose and lipid profile were determined using routine laboratory methods. Serum insulin, leptin, adiponectin, resistin, tumor necrosis factor-α, and PAI-1 were quantified using customized multiplex assay kits. High sensitive C-reactive protein (hsCRP) and angiotensin II (ANG II) were measured using ELISAs. Circulating leukocyte TL was examined by quantitative real-time PCR. Circulating chromosomal leukocyte TL had significant inverse associations with body mass index (BMI), systolic blood pressure, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), low-density lipoprotein (LDL)- and total cholesterol, ANG II and hsCRP levels. Adiponectin, BMI, systolic blood pressure, and LDL cholesterol predicted 47% of the variance in TL (P<0.0001). HOMA-IR was the most significant predictor for TL in males, explaining 35% of the variance (P=0.01). In females, adiponectin accounted for 28% of the variance in TL (P=0.01). Obesity and insulin resistance are associated with chromosomal TL among adult Arabs. Evidence of causal relations needs further investigation. The positive association of adiponectin to TL has clinical implications as to the possible protective effects of this hormone from accelerated aging.

Adiposity and insulin resistance correlate with telomere length in middle-aged Arabs: the influence of circulating adiponectin

PubMed Central

Al-Attas, Omar S; Al-Daghri, Nasser M; Alokail, Majed S; Alfadda, Assim; Bamakhramah, Ahmed; Sabico, Shaun; Pritlove, Dave; Harte, Alison; Tripathi, Gyanendra; McTernan, Philip G; Kumar, Sudhesh; Chrousos, George

2010-01-01

Objective Studies in obesity have implicated adipocytokines in the development of insulin resistance, which in turn may lead to accelerated aging. In this study, we determined associations of chromosomal telomere length (TL) to markers of obesity and insulin resistance in middle-aged adult male and female Arabs with and without diabetes mellitus type 2 (DMT2). Design and methods One hundred and ninety-three non-diabetic and DMT2 subjects without complications (97 males and 96 females) participated in this cross-sectional study. Clinical data, as well as fasting blood samples, were collected. Serum glucose and lipid profile were determined using routine laboratory methods. Serum insulin, leptin, adiponectin, resistin, tumor necrosis factor-α, and PAI-1 were quantified using customized multiplex assay kits. High sensitive C-reactive protein (hsCRP) and angiotensin II (ANG II) were measured using ELISAs. Circulating leukocyte TL was examined by quantitative real-time PCR. Results Circulating chromosomal leukocyte TL had significant inverse associations with body mass index (BMI), systolic blood pressure, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), low-density lipoprotein (LDL)- and total cholesterol, ANG II and hsCRP levels. Adiponectin, BMI, systolic blood pressure, and LDL cholesterol predicted 47% of the variance in TL (P<0.0001). HOMA-IR was the most significant predictor for TL in males, explaining 35% of the variance (P=0.01). In females, adiponectin accounted for 28% of the variance in TL (P=0.01). Conclusion Obesity and insulin resistance are associated with chromosomal TL among adult Arabs. Evidence of causal relations needs further investigation. The positive association of adiponectin to TL has clinical implications as to the possible protective effects of this hormone from accelerated aging. PMID:20679357

Leukocyte Telomere Length in Alzheimer's Disease Patients with a Different Rate of Progression.

PubMed

Tedone, Enzo; Arosio, Beatrice; Colombo, Federico; Ferri, Evelyn; Asselineau, Delphine; Piette, Francois; Gussago, Cristina; Belmin, Joel; Pariel, Sylvie; Benlhassan, Khadija; Casati, Martina; Bornand, Anne; Rossi, Paolo Dionigi; Mazzola, Paolo; Annoni, Giorgio; Doulazmi, Mohamed; Mariani, Jean; Porretti, Laura; Bray, Dorothy H; Mari, Daniela

2015-01-01

Age and short leukocyte telomeres have been associated with a higher risk of Alzheimer's disease (AD). Inflammation is involved in AD and it is suggested that anti-inflammatory interleukin-10 (IL-10) may partly antagonize these processes. The aim is to correlate telomere length (TL) in peripheral blood mononuclear cells (PBMC) from patients with AD to disease progression rate. Moreover, we evaluated whether TL was associated with IL-10 production by unstimulated or amyloid-β (Aβ)-stimulated PBMC. We enrolled 31 late-onset AD and 20 age-matched healthy elderly (HE). After a two-year follow-up period, patients were retrospectively evaluated as slow-progressing (ADS) (Mini Mental State Examination (MMSE) decline over the two years of follow-up ≤3 points) or fast progressing AD (ADF) (MMSE decline ≥5 points). TL was measured by flow cytometry and in vitro IL-10 production by enzyme-linked immunosorbent assay. TL (mean±SD) for HE, ADS, and ADF was 2.3±0.1, 2.0±0.1, and 2.5±0.1 Kb, respectively. ADS showed a shorter TL compared to HE (p = 0.034) and to ADF (p = 0.005). MMSE decline correlated with TL in AD (R2 = 0.284; p = 0.008). We found a significant difference in IL-10 production between unstimulated and Aβ-stimulated PBMC from ADS (40.7±13.7 versus 59.0±27.0; p = 0.004) but not from ADF (39.7±14.4 versus 42.2±22.4). HE showed a trend toward significance (47.1±25.4 versus 55.3±27.9; p = 0.10). PBMC from ADF may be characterized by an impaired response induced by Aβ and by a reduced proliferative response responsible for the longer telomeres. TL might be a contributing factor in predicting the rate of AD progression.

Effects of atrial fibrillation on myocardial washout rate of thallium-201 on myocardial perfusion single-photon emission computed tomography.

PubMed

Kurisu, Satoshi; Nitta, Kazuhiro; Sumimoto, Yoji; Ikenaga, Hiroki; Ishibashi, Ken; Fukuda, Yukihiro; Kihara, Yasuki

2018-04-20

Myocardial perfusion single-photon emission computed tomography (SPECT) with thallium (Tl)-201 is an established modality for evaluating myocardial ischemia. We assessed the effects of atrial fibrillation (AF) on the myocardial washout rate (WR) of Tl-201 on myocardial perfusion SPECT. A total of 231 patients with no evidence of myocardial ischemia were enrolled retrospectively in this study. Patients were divided into two groups on the basis of the ECG at the time of myocardial perfusion SPECT. The mean myocardial WR of Tl-201 was calculated from the stress and the redistribution Bull's eye maps. There were 34 patients with AF and 197 patients with sinus rhythm. There were no significant differences in clinical variables, except for older age and higher heart rate in patients with AF. Myocardial WR of Tl-201 was significantly lower in patients with AF than those with sinus rhythm (46±12 vs. 51±8%, P=0.03). Multivariate analysis including these factors showed that female sex (β=0.18, P=0.02), AF (β=-0.14 P=0.03), hemoglobin (β=-0.18, P<0.01), and serum creatinine (β=0.24, P<0.01) were determinants of myocardial WR of Tl-201. Our data suggest that AF is associated with reduced myocardial WR of Tl-201 on myocardial perfuison SPECT.

Effect of UV irradiation on different types of luminescence of SrAl2 O4 :Eu,Dy phosphors.

PubMed

Jha, Piyush

2016-11-01

This paper reports the luminescence behavior of Sr 0.097 Al 2 O 4 :Eu 0.01 ,Dy 0.02 phosphors under UV-irradiation. The effect of UV-irradiation on afterglow (AG), thermoluminescence (TL) and mechanoluminescence (ML) of Sr 0.097 Al 2 O 4 :Eu 0.01 ,Dy 0.02 phosphors is investigated. The space group of Sr 0.097 Al 2 O 4 :Eu 0.01 ,Dy 0.02 phosphors is monoclinic P2 1 . The prepared phosphors exhibit a long AG, intense TL and ML. It is found that the AG, ML intensity and TL increase with increasing duration of irradiation time. The ML intensity decreases with successive impact of the load onto the phosphors, whereby the diminished ML intensity can be recovered by UV-irradiation. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Patched Skin Bilirubin Assay to Monitor Neonates Born Extremely Preterm Undergoing Phototherapy.

PubMed

De Luca, Daniele; Dell'Orto, Valentina

2017-09-01

To verify the reliability and safety of transcutaneous bilirubin (TcB) measurements in patched skin areas in neonates born extremely preterm under phototherapy. Sixty neonates (<30 weeks' gestation) receiving phototherapy were enrolled and TcB was measured via a second-generation transcutaneous bilirubinometer in patched skin areas (of at least 2.5 cm diameter). Total serum bilirubin (TSB), lactate, pH, hemoglobin, and skin temperature were measured within 10 minutes of the TcB assay. Clinicians were blinded to TcB values, and clinical decisions about phototherapy were made with the TSB measurement only. TcB and TSB significantly were correlated (r = 0.84; P <.001), even after adjustment for hemoglobin, pH, lactate, gestational and postnatal age (standardized β = 0.8; P <.001; adjusted R 2  = 0.75), or treatment duration (standardized β = 0.8; P <.001; adjusted R 2  = 0.7). When the Bland-Altman analysis was used, TcB overestimated TSB at high values (mean difference TSB - TcB: -2.8 [2.4] mg/dL). If clinicians used the TcB only, no neonate would have had phototherapy stopped prematurely, and 21 (35%) would have continued phototherapy when it could have been stopped. The correlation between TSB and TcB (measured in patched skin areas) was comparable with that obtained in more mature neonates, and it was not influenced by clinical variables or factors affecting skin bilirubin passage. TcB overestimated TSB, and this may expose infants born preterm to unnecessary phototherapy, although it could spare approximately 65% of TSB assays. Copyright © 2017 Elsevier Inc. All rights reserved.

Shining Light on Nanotechnology to Help Repair and Regeneration

PubMed Central

Gupta, Asheesh; Avci, Pinar; Sadasivam, Magesh; Chandran, Rakkiyappan; Parizotto, Nivaldo; Vecchio, Daniela; Antunes-Melo, Wanessa C; Dai, Tianhong; Chiang, Long Y.; Hamblin, Michael R.

2012-01-01

Phototherapy can be used in two completely different but complementary therapeutic applications. While low level laser (or light) therapy (LLLT) uses red or near-infrared light alone to reduce inflammation, pain and stimulate tissue repair and regeneration, photodynamic therapy (PDT) uses the combination of light plus non-toxic dyes (called photosensitizers) to produce reactive oxygen species that can kill infectious microorganisms and cancer cells or destroy unwanted tissue (neo-vascularization in the choroid, atherosclerotic plaques in the arteries). The recent development of nanotechnology applied to medicine (nanomedicine) has opened a new front of advancement in the field of phototherapy and has provided hope for the development of nanoscale drug delivery platforms for effective killing of pathological cells and to promote repair and regeneration. Despite the well-known beneficial effects of phototherapy and nanomaterials in producing the killing of unwanted cells and promoting repair and regeneration, there are few reports that combine all three elements i.e. phototherapy, nanotechnology and, tissue repair and regeneration. However, these areas in all possible binary combinations have been addressed by many workers. The present review aims at highlighting the combined multi-model applications of phototherapy, nanotechnology and, reparative and regeneration medicine and outlines current strategies, future applications and limitations of nanoscale-assisted phototherapy for the management of cancers, microbial infections and other diseases, and to promote tissue repair and regeneration. PMID:22951919

Thallous chalcogenide (Tl 6I 4Se) for radiation detection at X-ray and γ-ray energies

NASA Astrophysics Data System (ADS)

Liu, Zhifu; Peters, John A.; Wessels, Bruce W.; Johnsen, Simon; Kanatzidis, Mercouri G.

2011-12-01

The optical and charge transport properties of the thallous chalcogenide compound Tl6I4Se were characterized. The semiconductor crystals are grown by the modified Bridgman method. We have measured the refractive index, and absorption coefficient of the compound ranging from 300 to 1500 nm by analysis of the UV-vis-near IR transmission and reflection spectra. The band gap is 1.8 eV. For the evaluation of detector performance, the mobility-lifetime products for both the electron and hole carriers were measured. Tl6I4Se has mobility-lifetime products of 7.1×10-3 and 5.9×10-4 cm2/V for electron and hole carriers, respectively, which are comparable to those of Cd0.9Zn0.1Te. The γ-ray spectrum for a Tl6I4Se detector was measured. Its response to the 122 keV of 57Co source is comparable to that of Cd0.9Zn0.1Te.

The pattern and time course of somatosensory changes in the human UVB sunburn model reveal the presence of peripheral and central sensitization.

PubMed

Gustorff, Burkhard; Sycha, Thomas; Lieba-Samal, Doris; Rolke, Roman; Treede, Rolf-Detlef; Magerl, Walter

2013-04-01

The ultraviolet B (UVB) sunburn model was characterized with a comprehensive battery of quantitative sensory testing (QST). Primary hyperalgesia in UVB-irradiated skin and secondary hyperalgesia in adjacent nonirradiated skin were studied in 22 healthy subjects 24h after irradiation with UVB at 3-fold minimal erythema dose of a skin area 5 cm in diameter at the thigh and compared to mirror-image contralateral control areas. The time course of hyperalgesia over 96 h was studied in a subgroup of 12 subjects. Within the sunburn area, cold hyperesthesia (P=.01), profound generalized hyperalgesia to heat (P<.001), cold (P<.05), pinprick and pressure (P<.001), and mild dynamic mechanical allodynia (P<.001) were present. The finding of cold hyperalgesia and cold hyperesthesia is new in this model. The sunburn was surrounded by large areas of pinprick hyperalgesia (mean±SEM, 218±32 cm(2)) and a small rim of dynamic mechanical allodynia but no other sensory changes. Although of smaller magnitude, secondary hyperalgesia and dynamic mechanical allodynia adjacent to the UVB-irradiated area were statistically highly significant. Primary and secondary hyperalgesia developed in parallel within hours, peaked after 24-32 h, and lasted for more than 96 h. These data reveal that the UVB sunburn model activates a broad spectrum of peripheral and central sensitization mechanisms and hence is a useful human surrogate model to be used as a screening tool for target engagement in phases 1 and 2a of drug development. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

The effect of vitamin C deficiency and chronic ultraviolet-B exposure on corneal ultrastructure: a preliminary investigation

PubMed Central

Hayes, Sally; Cafaro, Thamara A.; Boguslawska, Patrycja J.; Kamma-Lorger, Christina S.; Boote, Craig; Harris, Jonathan; Young, Robert; Hiller, Jennifer; Terrill, Nicholas; Meek, Keith M.

2011-01-01

Purpose In the visually debilitating condition of climatic droplet keratopathy, corneal transparency is progressively lost. Although the precise cause of the disease and the mechanism by which it progresses are not known, a lifetime exposure to high solar radiation and a vitamin C–deficient diet may be involved in its development. This study examines the effect of dietary ascorbate levels and ultraviolet (UV)-B exposure on corneal stromal structure. Methods Eight guinea pigs were divided into four treatment groups (A, B, C, and D). For 15 weeks, Groups A and C were fed an ascorbate-rich diet (2 mg/100 g bodyweight/day), while Groups B and D received an ascorbate-deficient diet (0.07 mg/100 g bodyweight/day). For the last 12 weeks of the study, Groups C and D also experienced chronic UVB exposure (0.12 J/cm2 for 40 min/day). Following euthanasia, the corneas were enucleated and their stromal ultrastructure examined using X-ray scattering and electron microscopy. Results UVB exposure resulted in an increased corneal thickness (p<0.001), but this was not accompanied by a widespread expansion of the collagen fibrillar array, and in the case of ascorbate-deficient animals, stromal thickening was associated with the compaction of collagen fibrils (p<0.01). Neither UVB exposure nor ascorbic acid deficiency caused any change in the average diameter or D-periodicity of the stromal collagen fibrils. Conclusions UVB-induced changes in the corneal ultrastructure were most pronounced in animals fed an ascorbic acid–deficient diet. This suggests that ascorbic acid may play a vital role in protecting the corneal stroma from the harmful effects of UVB. PMID:22171156

Incorporation of photobiomodulation therapy into a therapeutic exercise program for knee osteoarthritis: A placebo-controlled, randomized, clinical trial.

PubMed

de Paula Gomes, Cid A F; Leal-Junior, Ernesto C P; Dibai-Filho, Almir V; de Oliveira, Adriano R; Bley, André S; Biasotto-Gonzalez, Daniela A; de Tarso Camillo de Carvalho, Paulo

2018-05-07

To investigate the clinical effects of incorporation of phototherapy in a therapeutic exercise program for individuals with knee osteoarthritis (OA) when compared to a group that received exercise alone and to a group that received exercise + placebo phototherapy. This is a randomized, blinded and placebo-controlled trial. Thus, sixty male and female individuals aged 40-80 years with knee pain in the previous 6 months participated of the study, with diagnosis of unilateral knee OA based on the criteria established by the American College of Rheumatology and radiographic confirmation and Grades 2 or 3 of the Kellgren-Lawrence Classification. The individuals were equally divided in the groups exercise alone, exercise + active phototherapy (nine-diode cluster device: one 905 nm super-pulsed diode laser, four 875 nm LED and four 640 nm LED; energy per quadrant: 7.85 J; total energy: 23.55 J per session), or exercise + placebo phototherapy. Treatments were performed twice a week for 5 consecutive weeks. Patients were evaluated before and after the sessions of treatment. The outcome measures were: Western Ontario and McMaster University Osteoarthritis Index (WOMAC), Lower Extremity Functional Scale (LEFS), Numerical Rating Pain Scale (NRPS), pressure pain threshold (PPT) in two points of knee, muscle strength, and the Functional Reach Test (FRT). Exercise + active phototherapy was significantly more effective than exercise alone (mean difference [MD] = 2.75, 95% confidence interval [CI] = 3.17 to 2.32) and exercise + placebo phototherapy (MD = 2.38, 95% CI = 2.79 to 1.96) only with regard to the NRPS, considering minimal clinically important difference. No clinical significant results were found for function, the pressure pain threshold, muscle strength or balance. The combination of phototherapy and an exercise program is effective at reducing pain intensity among individuals with knee osteoarthritis than exercise alone or exercise + placebo phototherapy in a short-term protocol. Lasers Surg. Med. 9999: 1-10, 2018 © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Glucose-6-phosphate dehydrogenase (G6PD)-deficient infants: Enzyme activity and gene variants as risk factors for phototherapy in the first week of life.

PubMed

Wong, Fei-Liang; Ithnin, Azlin; Othman, Ainoon; Cheah, Fook-Choe

2017-07-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a recognised cause of severe neonatal hyperbilirubinaemia, and identifying which infants are at risk could optimise care and resources. In this study, we determined if G6PD enzyme activity (EA) and certain gene variants were associated with neonatal hyperbilirubinaemia requiring phototherapy during the first week after birth. Newborn infants with G6PD deficiency and a group with normal results obtained by the fluorescent spot test were selected for analyses of G6PD EA and the 10 commonly encountered G6PD mutations in this region, relating these with whether the infants required phototherapy before discharge from the hospital in the first week. A total of 222 infants with mean gestation and birth weight of 38.3 ± 1.8 weeks and 3.02 ± 0.48 kg, respectively, were enrolled. Of these, n = 121 were deficient with EA ≤6.76 U/g Hb, and approximately half (43%) received phototherapy in the first week after birth. The mean EA level was 3.7 U/g Hb. The EA had good accuracy in predicting phototherapy use, with area under the receiver-operating-characteristic curve of 0.81 ± 0.05. Infants on phototherapy more commonly displayed World Health Organization Class II mutations (<10% residual EA). Logistic regression analysis showed that deficiency in EA and mutation at c.1388G>A (adjusted odds ratio, 1.5 and 5.7; 95% confidence interval: 1.31-1.76 and 1.30-25.0, respectively) were independent risk factors for phototherapy. Low G6PD EA (<6.76 U/g Hb) and the G6PD gene variant, c.1388G>A, are risk factors for the need of phototherapy in newborn infants during the first week after birth. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

Bili lights

MedlinePlus

Phototherapy for jaundice; Bilirubin - bili lights; Neonatal care - bili lights; Newborn care - bili lights ... Phototherapy involves shining fluorescent light from the bili lights on bare skin. A specific wavelength of light can break down bilirubin into a form that ...

[The use of phototherapy and photochromotherapy in the combined treatment of the patients presenting with astheno-depressive syndrome and neurotic disorders].

PubMed

Kir'ianova, V V; Baburin, I N; goncharova, V G; Veselovskiĭ, A B

2012-01-01

The objective of the present clinical and psychopathological study was to estimate the influence of high-intensity white and yellow phototherapy on the clinical condition of 41 and 18 patients respectively presenting with astheno-depressive syndrome. The control group was comprised of 42 patients who were treated by standard pharmacotherapy. Clinical observations of the patients were supplemented by the evaluation of their conditions and characteristics using the Symptom Checklist-90 questionnaire, the Bekhterev Depression Inventory, and the Beck Depression Inventory. The patients of the three groups were surveyed before and within 20 days after the initiation of the treatment. It was shown that white light phototherapy considerably reduced the severity of asthenia and depression. Yellow light phototherapy proved more efficacious in the patients with asthenia and somatovegetative dysfunctions.

Low-Power Testing of Losses in Millimeter-Wave Transmission Lines for High-Power Applications

PubMed Central

Han, S. T.; Comfoltey, E. N.; Shapiro, M. A.; Sirigiri, J. R.; Tax, D. S.; Temkin, R. J.; Woskov, P. P.; Rasmussen, D. A.

2008-01-01

We report the measurement of small losses in transmission line (TL) components intended for high-power millimeter-wave applications. Measurements were made using two different low-power techniques: a coherent technique using a vector network analyzer (VNA) and an incoherent technique using a radiometer. The measured loss in a 140 GHz 12.7 mm diameter TL system, consisting of 1.7 m of circular corrugated waveguide and three miter bends, is dominated by the miter bend loss. The measured loss was 0.3±0.1 dB per miter bend using a VNA; and 0.22±0.1 dB per miter bend using a radiometer. Good agreement between the two measurement techniques implies that both are useful for measuring small losses. To verify the methodology, the VNA technique was employed to measure the extremely small transmission loss in a 170 GHz ITER prototype TL system consisting of three lengths of 1 m, 63.5 mm diameter, circular corrugated waveguide and two miter bends. The measured loss of 0.05±0.02 dB per miter bend may be compared with the theoretical loss of 0.027 dB per miter bend. These results suggest that low-power testing of TL losses, utilizing a small, simple TL system and a VNA, is a reliable method for evaluating performance of low-loss millimeter-wave TL components intended for use in high-power applications. PMID:19081774

Telomere Length Attrition, a Marker of Biological Senescence, Is Inversely Correlated with Triglycerides and Cholesterol in South Asian Males with Type 2 Diabetes Mellitus

PubMed Central

Harte, Alison L.; da Silva, Nancy F.; Miller, Michelle A.; Cappuccio, Francesco P.; Kelly, Ann; O'Hare, Joseph P.; Barnett, Anthony H.; Al-Daghri, Nasser M.; Al-Attas, Omar; Alokail, Majed; Sabico, Shaun; Tripathi, Gyanendra; Bellary, Srikanth; Kumar, Sudhesh; McTernan, Philip G.

2012-01-01

South Asians have a higher risk of type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) than white Caucasians, for a given BMI. Premature biological ageing, assessed by reduction in telomere length (TL), may be mediated by factors resulting from altered metabolic profiles associated with obesity. We hypothesise that ethnicity and metabolic status represent detrimental factors contributing to premature biological ageing. Therefore we assessed TL in two South Asian, age and BMI-matched cohorts [T2DM (n = 142) versus non-T2DM (n = 76)] to determine the effects of BMI, gender, lipid and CVD profile on biological ageing. Genomic DNA was obtained from the UKADS cohort; biochemical and anthropometric data was collected and TL was measured by quantitative real-time PCR. Our findings indicated a gender-specific effect with reduced TL in T2DM men compared with non-T2DM men (P = 0.006). Additionally, in T2DM men, TL was inversely correlated with triglycerides and total cholesterol (r = −0.419, P < 0.01; r = −0.443, P < 0.01). In summary, TL was reduced amongst South Asian T2DM men and correlated with triglycerides and total cholesterol. This study highlights enhanced biological ageing among South Asian, T2DM men, which appears to be tracked by changes in lipids and BMI, suggesting that raised lipids and BMI may directly contribute to premature ageing. PMID:22474429

Lack of photoprotection against UVB-induced erythema by immediate pigmentation induced by 382 nm radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Black, G.; Matzinger, E.; Gange, R.W.

Immediate pigment darkening (IPD) was induced on the backs of 11 human volunteers of skin types III and IV by exposing the skin to UVA radiation (382 nm). The minimum erythema dose (MED) of UVB radiation was also determined by exposing sites to graduated doses of 304 nm radiation. The order of exposure of distinct anatomic areas was as follow: UVB followed by IPD induction; IPD induction followed by UVB; IPD induction followed 3 h later by UVB; and UVB only. Erythema responses induced by UVB were graded by inspection 24 h later and the MEDs in the 4 areasmore » were compared. The induction of IPD before UVB exposure caused no significant change in the MED compared to sites receiving UVB only, or receiving UVA radiation after UVB, confirming that the IPD reaction does not protect against UVB-induced erythema. There was also no evidence of photorecovery, i.e., an increase in the MED of UVB resulting from exposure to longer wavelength, UV or visible radiation following UVB exposure.« less

Neonatal phototherapy radiometers: current performance characteristics and future requirements.

PubMed

Clarkson, Douglas McG; Nicol, Ruth; Chapman, Phillip

2014-04-01

Hand held radiometers provide a convenient means of monitoring the output of neonatal phototherapy treatment devices as part of planned programs of device maintenance and output monitoring. It was considered appropriate to determine the wavelength and angular response of a selection of such meters and compare their indicated values with that derived from spectral analysis of phototherapy light sources. This was undertaken using a Bentham DMc150 double grating spectroradiometer and a series of 10nm band pass optical filters in the range 400-640 nm used in conjunction with a fiber optic light source. Specific meters investigated included a GE Biliblanket Light Meter II, a NeoBLUE radiometer and a Bio-TEK radiometer 74345 device. Comparisons were made of measurements made using the hand held meters and the Bentham DMc 150 system for a range of neonatal phototherapy treatment devices. The use of such meters is discussed in relation to applicable equipment standards and recommendations of intensive phototherapy from clinical groups such as the American Academy of Pediatrics and a specification for a spectroradiometer based measurement system is proposed. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

Targeted Imaging and Chemo-Phototherapy of Brain Cancer by a Multifunctional Drug Delivery System.

PubMed

Hao, Yongwei; Wang, Lei; Zhao, Yalin; Meng, Dehui; Li, Dong; Li, Haixia; Zhang, Bingxiang; Shi, Jinjin; Zhang, Hongling; Zhang, Zhenzhong; Zhang, Yun

2015-11-01

The aim of this study was to develop multifunctional poly lactide-co-glycolide (PLGA) nanoparticles with the ability to simultaneously deliver indocyanine green (ICG) and docetaxel (DTX) to the brain by surface decoration with the brain-targeting peptide angiopep-2 to achieve combined chemo-phototherapy for glioma under near-infrared (NIR) imaging. ICG was selected as a near-infrared imaging and phototherapy agent and DTX was employed as a chemotherapeutic agent. ICG and DTX were simultaneously incorporated into PLGA nanoparticles with higher stability. These nanoparticles were further decorated with angiopep-2 via the outer maleimide group of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000]-maleinimide incorporated in the nanoparticles. The NIR image-guided chemo-phototherapy of the angiopep-2 modified PLGA/DTX/ICG nanoparticles (ANG/PLGA/DTX/ICG NPs) not only highly induced U87MG cell death in vitro, but also efficiently prolonged the life span of the brain orthotopic U87MG glioma xenograft-bearing mice in vivo. Thus, this study suggests that ANG/PLGA/DTX/ICG NPs have the potential for combinatorial chemotherapy and phototherapy for glioma. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cannabinoid CB2 receptor as a new phototherapy target for the inhibition of tumor growth.

PubMed

Jia, Ningyang; Zhang, Shaojuan; Shao, Pin; Bagia, Christina; Janjic, Jelena M; Ding, Ying; Bai, Mingfeng

2014-06-02

The success of targeted cancer therapy largely relies upon the selection of target and the development of efficient therapeutic agents that specifically bind to the target. In the current study, we chose a cannabinoid CB2 receptor (CB2R) as a new target and used a CB2R-targeted photosensitizer, IR700DX-mbc94, for phototherapy treatment. IR700DX-mbc94 was prepared by conjugating a photosensitizer, IR700DX, to mbc94, whose binding specificity to CB2R has been previously demonstrated. We found that phototherapy treatment using IR700DX-mbc94 greatly inhibited the growth of CB2R positive tumors but not CB2R negative tumors. In addition, phototherapy treatment with nontargeted IR700DX did not show significant therapeutic effect. Similarly, treatment with IR700DX-mbc94 without light irradiation or light irradiation without the photosensitizer showed no tumor-inhibitory effect. Taken together, IR700DX-mbc94 is a promising phototherapy agent with high target-specificity. Moreover, CB2R appears to have great potential as a phototherapeutic target for cancer treatment.

Clinical comparison of salicylic acid peel and LED-Laser phototherapy for the treatment of Acne vulgaris in teenagers.

PubMed

Alba, Monique Narciso; Gerenutti, Marli; Yoshida, Valquíria Miwa Hanai; Grotto, Denise

2017-02-01

Acne vulgaris treatments usually cause sensitivity, teratogenicity and bacterial resistance. Investigations of other therapeutic techniques, such as phototherapy, are highly relevant. Thus, we compared the effectiveness of two Acne vulgaris treatments in adolescents: peeling with salicylic acid (SA) and phototherapy. Teens were randomly divided into: group I, treatment with SA peels (10%) and group II, treatment with phototherapy (blue LED and red laser lights). Photographs were taken before and after ten sessions of each treatment, carried out weekly, and compared. To compare the differences between the treatments, the Student t-test was used. P values < 0.05 were considered significant. Both techniques are effective therapies for the treatment of acne in teenagers since the number of comedones, papules and pustules decreased significantly at the end of the session. However, when the two treatments were compared, phototherapy showed a significant difference in reducing the number of pustules. The combined use of red and blue lights due to their anti-inflammatory and wound-healing properties is a more efficient alternative for treating Acne vulgaris in relation to SA and proves more reliable and without side effects, improving the adolescents' skin health.

A pilot study on quantification of training load: The use of HRV in training practice.

PubMed

Saboul, Damien; Balducci, Pascal; Millet, Grégoire; Pialoux, Vincent; Hautier, Christophe

2016-01-01

Recent laboratory studies have suggested that heart rate variability (HRV) may be an appropriate criterion for training load (TL) quantification. The aim of this study was to validate a novel HRV index that may be used to assess TL in field conditions. Eleven well-trained long-distance male runners performed four exercises of different duration and intensity. TL was evaluated using Foster and Banister methods. In addition, HRV measurements were performed 5 minutes before exercise and 5 and 30 minutes after exercise. We calculated HRV index (TLHRV) based on the ratio between HRV decrease during exercise and HRV increase during recovery. HRV decrease during exercise was strongly correlated with exercise intensity (R = -0.70; p < 0.01) but not with exercise duration or training volume. TLHRV index was correlated with Foster (R = 0.61; p = 0.01) and Banister (R = 0.57; p = 0.01) methods. This study confirms that HRV changes during exercise and recovery phase are affected by both intensity and physiological impact of the exercise. Since the TLHRV formula takes into account the disturbance and the return to homeostatic balance induced by exercise, this new method provides an objective and rational TL index. However, some simplification of the protocol measurement could be envisaged for field use.

Thermoelectric properties of Tl and I dual-doped Bi2Te3-based alloys

NASA Astrophysics Data System (ADS)

Wu, Fang; He, Qinglin; Tang, Mingsheng; Song, Hongzhang

2018-04-01

TlxBi2‑xTe3‑xIx (x = 0, 0.05, 0.1 and 0.2) flower-like nanopowders were prepared successfully by the hydrothermal method. Then, the synthesized nanoparticles were pressed into bulks by hot-pressing. The thermoelectric (TE) properties of the TlxBi2‑xTe3‑xIx bulk samples were investigated and discussed. The results showed that the influences of Tl doping on the electrical resistivity and Seebeck coefficients of the Bi2Te3 is over that of I doping. Thus, the power factors of the dual-doped bulks are all less than that of the Bi2Te3 bulk. The thermal conductivities of the TlxBi2‑xTe3‑xIx bulk samples also remain at lower values. As a result, the ZT value of the optimized doped bulk Tl0.1Bi1.9Te2.9I0.1 attains a value of 1.1 at 398 K.

[Magnetotherapy of initial manifestations of cerebrovascular disorders in hypertension].

PubMed

Miasnikov, I G

1992-01-01

The paper is concerned with the data on 147 subjects who underwent magnetotherapy with the unit "Magniter-AMT-01" applied to the cervical area. The main group included 102 subjects, 45 person served as control. The purpose of the work was to base the application of MT under inpatient and home conditions with the use of the above-indicated unit. In view of this fact, a study was made of cerebral hemo- and thermodynamics with the aid of rheoencephalography and encephaloradiothermography under the action of different modes of the functioning of the unit "Magniter-AMT-01" (pulse and variable magnet induction fields 12-15 mTl and 30-35 mTl). A method of measuring magnetosensitivity of patients depending on the temperature reaction of the brain to a single MT session was elaborated. The greatest clinical effect was attained with the use of pulse magnetic field 15 mTl. Magnetotherapy with the use of the unit "Magniter-AMT-01" provided good results under inpatient and home conditions. The magnetosensitive patients demonstrated the highest effect.

U.S. EPA, Pesticide Product Label, , 03/01/1982

EPA Pesticide Factsheets

2011-04-14

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Attenuation of UV-B exposure-induced inflammation by abalone hypobranchial gland and gill extracts.

PubMed

Kuanpradit, Chitraporn; Jaisin, Yamaratee; Jungudomjaroen, Sumon; Akter Mitu, Shahida; Puttikamonkul, Srisombat; Sobhon, Prasert; Cummins, Scott F

2017-05-01

Exposure to solar ultraviolet B (UV-B) is a known causative factor for many skin complications such as wrinkles, black spots, shedding and inflammation. Within the wavelengths 280‑320 nm, UV-B can penetrate to the epidermal level. This investigation aimed to test whether extracts from the tropical abalone [Haliotis asinina (H. asinina)] mucus-secreting tissues, the hypobranchial gland (HBG) and gills, were able to attenuate the inflammatory process, using the human keratinocyte HaCaT cell line. Cytotoxicity of abalone tissue extracts was determined using an AlamarBlue viability assay. Results showed that HaCaT cells could survive when incubated in crude HBG and gill extracts at concentrations between <11.8 and <16.9 µg/ml, respectively. Subsequently, cell viability was compared between cultured HaCaT cells exposed to serial doses of UV-B from 1 to 11 (x10) mJ/cm2 and containing 4 different concentrations of abalone extract from both the HBG and gill (0, 0.1, 2.5, 5 µg/ml). A significant increase in cell viability was observed (P<0.001) following treatment with 2.5 and 5 µg/ml extract. Without extract, cell viability was significantly reduced upon exposure to UV-B at 4 mJ/cm2. Three morphological changes were observed in HaCaT cells following UV-B exposure, including i) condensation of cytoplasm; ii) shrunken cells and plasma membrane bubbling; and iii) condensation of chromatin material. A calcein AM‑propidium iodide live‑dead assay showed that cells could survive cytoplasmic condensation, yet cell death occurred when damage also included membrane bubbling and chromatin changes. Western blot analysis of HaCaT cell COX‑2, p38, phospho‑p38, SPK/JNK and phospho‑SPK/JNK following exposure to >2.5 µg/ml extract showed a significant decrease in intensity for COX‑2, phospho‑p38 and phospho‑SPK/JNK. The present study demonstrated that abalone extracts from the HGB and gill can attenuate inflammatory proteins triggered by UV-B. Hence, the contents of abalone extract, including cellmetabolites and peptides, may provide new agents for skin anti‑inflammation, preventing damage due to UV-B.

Attenuation of UV-B exposure-induced inflammation by abalone hypobranchial gland and gill extracts

PubMed Central

Kuanpradit, Chitraporn; Jaisin, Yamaratee; Jungudomjaroen, Sumon; Mitu, Shahida Akter; Puttikamonkul, Srisombat; Sobhon, Prasert; Cummins, Scott F.

2017-01-01

Exposure to solar ultraviolet B (UV-B) is a known causative factor for many skin complications such as wrinkles, black spots, shedding and inflammation. Within the wavelengths 280–320 nm, UV-B can penetrate to the epidermal level. This investigation aimed to test whether extracts from the tropical abalone [Haliotis asinina (H. asinina)] mucus-secreting tissues, the hypobranchial gland (HBG) and gills, were able to attenuate the inflammatory process, using the human keratinocyte HaCaT cell line. Cytotoxicity of abalone tissue extracts was determined using an AlamarBlue viability assay. Results showed that HaCaT cells could survive when incubated in crude HBG and gill extracts at concentrations between <11.8 and <16.9 μg/ml, respectively. Subsequently, cell viability was compared between cultured HaCaT cells exposed to serial doses of UV-B from 1 to 11 (x10) mJ/cm2 and containing 4 different concentrations of abalone extract from both the HBG and gill (0, 0.1, 2.5, 5 μg/ml). A significant increase in cell viability was observed (P<0.001) following treatment with 2.5 and 5 μg/ml extract. Without extract, cell viability was significantly reduced upon exposure to UV-B at 4 mJ/cm2. Three morphological changes were observed in HaCaT cells following UV-B exposure, including i) condensation of cytoplasm; ii) shrunken cells and plasma membrane bubbling; and iii) condensation of chromatin material. A calcein AM-propidium iodide live-dead assay showed that cells could survive cytoplasmic condensation, yet cell death occurred when damage also included membrane bubbling and chromatin changes. Western blot analysis of HaCaT cell COX-2, p38, phospho-p38, SPK/JNK and phospho-SPK/JNK following exposure to >2.5 μg/ml extract showed a significant decrease in intensity for COX-2, phospho-p38 and phospho-SPK/JNK. The present study demonstrated that abalone extracts from the HGB and gill can attenuate inflammatory proteins triggered by UV-B. Hence, the contents of abalone extract, including cellmetabolites and peptides, may provide new agents for skin anti-inflammation, preventing damage due to UV-B. PMID:28358420

Biochemical changes on the repair of surgical bone defects grafted with biphasic synthetic micro-granular HA + β-tricalcium phosphate induced by laser and LED phototherapies and assessed by Raman spectroscopy.

PubMed

Pinheiro, Antônio Luiz Barbosa; Soares, Luiz Guilherme Pinheiro; Marques, Aparecida Maria Cordeiro; Cangussú, Maria Cristina Teixeira; Pacheco, Marcos Tadeu Tavares; Silveira, Landulfo

2017-04-01

This work aimed the assessment of biochemical changes induced by laser or LED irradiation during mineralization of a bone defect in an animal model using a spectral model based on Raman spectroscopy. Six groups were studied: clot, laser (λ = 780 nm; 70 mW), LED (λ = 850 ± 10 nm; 150 mW), biomaterial (biphasic synthetic micro-granular hydroxyapatite (HA) + β-tricalcium phosphate), biomaterial + laser, and biomaterial + LED. When indicated, defects were further irradiated at a 48-h interval during 2 weeks (20 J/cm 2 per session). At the 15th and 30th days, femurs were dissected and spectra of the defects were collected. Raman spectra were submitted to a model to estimate the relative amount of collagen, phosphate HA, and carbonate HA by using the spectra of pure collagen and biomaterials composed of phosphate and carbonate HA, respectively. The use of the biomaterial associated to phototherapy did not change the collagen formation at both 15 and 30 days. The amount of carbonate HA was not different in all groups at the 15th day. However, at the 30th day, there was a significant difference (ANOVA, p = 0.01), with lower carbonate HA for the group biomaterial + LED compared to biomaterial (p < 0.05). The phosphate HA was higher in the groups that received biomaterial grafts at the 15th day compared to clot (significant for the biomaterial; p < 0.01). At the 30th day, the phosphate HA was higher for the group biomaterial + laser, while this was lower for all the other groups. These results indicated that the use of laser phototherapy improved the repair of bone defects grafted with the biomaterial by increasing the deposition of phosphate HA.

The utility of inpatient rebound bilirubin levels in infants readmitted after birth hospitalization for hyperbilirubinemia.

PubMed

Berkwitt, Adam; Osborn, Rachel; Grossman, Matthew

2015-02-01

There are few data evaluating the role of inpatient rebound bilirubin levels in the management of infants readmitted after their birth hospitalization for indirect hyperbilirubinemia. The goal of the present study was to evaluate the clinical utility of inpatient rebound bilirubin levels within this patient population. A retrospective cohort study was conducted of 226 infants readmitted after their birth hospitalization for indirect hyperbilirubinemia. Data from 130 infants with rebound bilirubin levels drawn at a mean of 6.1±2.4 hours after discontinuation of phototherapy were compared with data from 96 infants without rebound bilirubin levels. The primary outcome was readmission to the hospital, and secondary outcomes included length of stay and discharge time. A subgroup analysis compared characteristics of children who required repeat phototherapy versus those who did not. Overall, 5 of 130 patients from the rebound group were readmitted compared with 4 of 96 patients from the no-rebound group (P=.98). Length of stay was significantly longer for patients with rebound bilirubin levels (27.7 vs 23.2 hours; P=.001). Patients with bilirubin levels lowered to ≤14 mg/dL were less likely to receive repeat phototherapy than those with levels>14 mg/dL (2 of 129 vs 12 of 97; P=.001). Early inpatient rebound bilirubin levels do not successfully predict which patients will require hospital readmission for repeat phototherapy. Children with bilirubin levels lowered to ≤14 mg/dL with phototherapy are unlikely to receive repeat phototherapy. Copyright © 2015 by the American Academy of Pediatrics.

Smart human serum albumin-indocyanine green nanoparticles generated by programmed assembly for dual-modal imaging-guided cancer synergistic phototherapy.

PubMed

Sheng, Zonghai; Hu, Dehong; Zheng, Mingbin; Zhao, Pengfei; Liu, Huilong; Gao, Duyang; Gong, Ping; Gao, Guanhui; Zhang, Pengfei; Ma, Yifan; Cai, Lintao

2014-12-23

Phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), is a light-activated local treatment modality that is under intensive preclinical and clinical investigations for cancer. To enhance the treatment efficiency of phototherapy and reduce the light-associated side effects, it is highly desirable to improve drug accumulation and precision guided phototherapy for efficient conversion of the absorbed light energy to reactive oxygen species (ROS) and local hyperthermia. In the present study, a programmed assembly strategy was developed for the preparation of human serum albumin (HSA)-indocyanine green (ICG) nanoparticles (HSA-ICG NPs) by intermolecular disulfide conjugations. This study indicated that HSA-ICG NPs had a high accumulation with tumor-to-normal tissue ratio of 36.12±5.12 at 24 h and a long-term retention with more than 7 days in 4T1 tumor-bearing mice, where the tumor and its margin, normal tissue were clearly identified via ICG-based in vivo near-infrared (NIR) fluorescence and photoacoustic dual-modal imaging and spectrum-resolved technology. Meanwhile, HSA-ICG NPs efficiently induced ROS and local hyperthermia simultaneously for synergetic PDT/PTT treatments under a single NIR laser irradiation. After an intravenous injection of HSA-ICG NPs followed by imaging-guided precision phototherapy (808 nm, 0.8 W/cm2 for 5 min), the tumor was completely suppressed, no tumor recurrence and treatments-induced toxicity were observed. The results suggest that HSA-ICG NPs generated by programmed assembly as smart theranostic nanoplatforms are highly potential for imaging-guided cancer phototherapy with PDT/PTT synergistic effects.

Redox-controlled release dynamics of thallium in periodically flooded arable soil.

PubMed

Antić-Mladenović, Svetlana; Frohne, Tina; Kresović, Mirjana; Stärk, Hans-Joachim; Savić, Dubravka; Ličina, Vlado; Rinklebe, Jörg

2017-07-01

To our knowledge, this is the first work to mechanistically study the impact of the redox potential (E H ) and principal factors, such as pH, iron (Fe), manganese (Mn), dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), chlorides (Cl - ) and sulfates (SO 4 2- ), on the release dynamics of thallium (Tl) in periodically flooded soil. We simulated flooding using an automated biogeochemical microcosm system that allows for systematical control of pre-defined redox windows. The E H value was increased mechanistically at intervals of approximately 100 mV from reducing (-211 mV) to oxidizing (475 mV) conditions. Soluble Tl levels (0.02-0.28 μg L -1 ) increased significantly with increases in E H (r = 0.80, p < 0.01, n = 30). Thallium mobilization was found to be related to several simultaneous processes involving the gradual oxidation of Tl-bearing sulfides, reductive dissolution of Fe-Mn oxides and desorption from mineral sorbents. Manganese oxides did not appear to have a considerable effect on Tl retention under oxidizing conditions. Before conducting the microcosm experiment, Tl geochemical fractionation was assessed using the modified BCR sequential extraction procedure. The BCR revealed a majority of Tl in the residual fraction (77.7%), followed by reducible (13.3%) and oxidizable fractions (5.9%). By generating high levels of Tl toxicity at low doses, Tl released under oxidizing conditions may pose an environmental threat. In the future, similar studies should be conducted on various soils along with a determination of the Tl species and monitoring of the Tl content in plants to achieve more detailed insight into soluble Tl behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

Extracorporeal treatment for thallium poisoning: recommendations from the EXTRIP Workgroup.

PubMed

Ghannoum, Marc; Nolin, Thomas D; Goldfarb, David S; Roberts, Darren M; Mactier, Robert; Mowry, James B; Dargan, Paul I; Maclaren, Robert; Hoegberg, Lotte C; Laliberté, Martin; Calello, Diane; Kielstein, Jan T; Anseeuw, Kurt; Winchester, James F; Burdmann, Emmanuel A; Bunchman, Timothy E; Li, Yi; Juurlink, David N; Lavergne, Valery; Megarbane, Bruno; Gosselin, Sophie; Liu, Kathleen D; Hoffman, Robert S

2012-10-01

The EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatment (ECTR) in poisoning. To test and validate its methods, the workgroup reviewed data for thallium (Tl). After an extensive search, the co-chairs reviewed the articles, extracted the data, summarized findings, and proposed structured voting statements following a predetermined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and RAND/UCLA Appropriateness Method to quantify disagreement. Blinded votes were compiled, returned, and discussed during a conference call. A second vote determined the final recommendations. Forty-five articles met inclusion criteria. Only case reports and case series were identified, yielding a very low quality of evidence for all recommendations. Data on 74 patients, including 11 who died, were abstracted. The workgroup concluded that Tl is slightly dialyzable and made the following recommendations: ECTR is recommended in severe Tl poisoning (1D). ECTR is indicated if Tl exposure is highly suspected on the basis of history or clinical features (2D) or if the serum Tl concentration is >1.0 mg/L (2D). ECTR should be initiated as soon as possible, ideally within 24-48 hours of Tl exposure (1D), and be continued until the serum Tl concentration is <0.1 mg/L for a minimal duration of 72 hours (2D). Despite Tl's low dialyzability and the limited evidence, the workgroup strongly recommended extracorporeal removal in the case of severe Tl poisoning.

Effects of blue light phototherapy on DNA integrity in preterm newborns.

PubMed

Gómez-Meda, Belinda C; Barros-Hernández, Angélica; Guzmán-Bárcenas, José; Lemus-Varela, María de Lourdes; Zamora-Perez, Ana L; Torres-Mendoza, Blanca M; Gallegos-Arreola, Martha P; Armendáriz-Borunda, Juan; Zúñiga-González, Guillermo M

2014-12-01

In previous studies, exposure to phototherapy, but not oxygen therapy, resulted in damage to genetic material in newborns. The objective of this study was to determine whether micronucleated erythrocytes (MNE) increased in preterm newborns (PNBs) who were exposed to blue light phototherapy lamps. MNE of mature organisms are rapidly eliminated by the spleen, and the presence of MNE has been related to immaturity in some species. Furthermore, PNBs present spontaneous MNE. Blood samples were taken from 17 PNBs at birth to establish baseline frequencies (0 h). After beginning blue light phototherapy, blood samples were obtained from 11 of these PNBs at 24-h intervals for 96 h, after the baseline sample. MNE and micronucleated polychromatic erythrocytes (MNPCE) were counted. The basal values of MNE and MNPCE from 17 PNBs were 0.62 ± 0.48 and 1.52 ± 1.28 (‰), respectively, and no increase in MNE or MNPCE was observed in the serial samples of 11 PNBs exposed to blue light and oxygen therapies, though previous studies reported increases using other types of lamps. In conclusion, under the conditions described no increase in the number of MNE or MNPCE was observed in the peripheral blood of PNBs exposed to blue light phototherapy. Copyright © 2014 Elsevier B.V. All rights reserved.

Syntonic phototherapy

NASA Astrophysics Data System (ADS)

Gottlieb, Raymond L.

2010-02-01

Syntonic phototherapy is an application of clinical phototherapy that is not well known by most LLLT photobiomodulation researchers and clinicians in spite of its long history. This is because of three main reasons: this approach was beyond the limits of the "reasonable" scientific paradigm, it has not been well researched and it is used mainly by optometrists. Clinical and basic researcher in the last decades about light's impact on cells, tissues, blood, circadian rhythms and mood disorders has broadened the paradigm and increased the acceptance of light as a healing agent. Perhaps now is an appropriate time to describe Syntonic optometric phototherapy with the purpose of exciting research to validate and expand its use. Syntonics uses non-coherent, non-polarized, broad-band light delivered into the eyes to treat brain injury, headache, strabismus, eye pathology, learning disability, mood and developmental syndromes. The eyes permit direct, non-invasive application of light to the retinal blood supply and to non-visual, retinal photoreceptor systems that signal circadian and other brain centers. Patients look at prescribed colors for 20-minutes/day for twenty treatments. Visual field, pupil, and binocular testing, medical history and current symptoms determine the syntonic filter prescription. Presentation describes syntonic theory, phototherapy device, visual field and pupil tests and cases reports with pre- and post-data and case resolution.

Caffeine and caffeine sodium benzoate have a sunscreen effect, enhance UVB-induced apoptosis, and inhibit UVB-induced skin carcinogenesis in SKH-1 mice.

PubMed

Lu, Yao-Ping; Lou, You-Rong; Xie, Jian-Guo; Peng, Qing-Yun; Zhou, Sherry; Lin, Yong; Shih, Weichung Joe; Conney, Allan H

2007-01-01

Topical application of caffeine sodium benzoate (caffeine-SB) immediately after UVB irradiation of SKH-1 mice enhanced UVB-induced apoptosis by a 2- to 3-fold greater extent than occurred after the topical application of an equimolar amount of caffeine. Although topical application of caffeine-SB or caffeine enhanced UVB-induced apoptosis, both substances were inactive on non-UVB-treated normal skin. Topical application of caffeine-SB or caffeine (each has UVB absorption properties) 0.5 h before irradiation with a high dose of UVB decreased UVB-induced thymine dimer formation and sunburn lesions (sunscreen effect). Caffeine-SB was more active than an equimolar amount of caffeine in exerting a sunscreen effect. In additional studies, caffeine-SB strongly inhibited the formation of tumors in UVB-pretreated 'high-risk mice' and in tumor-bearing mice, and the growth of UVB-induced tumors was also inhibited. Caffeine-SB and caffeine are the first examples of compounds that have both a sunscreen effect and enhance UVB-induced apoptosis. Our studies suggest that caffeine-SB and caffeine may be good agents for inhibiting the formation of sunlight-induced skin cancer.

UV-B Perception and Acclimation in Chlamydomonas reinhardtii[OPEN

PubMed Central

Chappuis, Richard; Allorent, Guillaume

2016-01-01

Plants perceive UV-B, an intrinsic component of sunlight, via a signaling pathway that is mediated by the photoreceptor UV RESISTANCE LOCUS8 (UVR8) and induces UV-B acclimation. To test whether similar UV-B perception mechanisms exist in the evolutionarily distant green alga Chlamydomonas reinhardtii, we identified Chlamydomonas orthologs of UVR8 and the key signaling factor CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1). Cr-UVR8 shares sequence and structural similarity to Arabidopsis thaliana UVR8, has conserved tryptophan residues for UV-B photoreception, monomerizes upon UV-B exposure, and interacts with Cr-COP1 in a UV-B-dependent manner. Moreover, Cr-UVR8 can interact with At-COP1 and complement the Arabidopsis uvr8 mutant, demonstrating that it is a functional UV-B photoreceptor. Chlamydomonas shows apparent UV-B acclimation in colony survival and photosynthetic efficiency assays. UV-B exposure, at low levels that induce acclimation, led to broad changes in the Chlamydomonas transcriptome, including in genes related to photosynthesis. Impaired UV-B-induced activation in the Cr-COP1 mutant hit1 indicates that UVR8-COP1 signaling induces transcriptome changes in response to UV-B. Also, hit1 mutants are impaired in UV-B acclimation. Chlamydomonas UV-B acclimation preserved the photosystem II core proteins D1 and D2 under UV-B stress, which mitigated UV-B-induced photoinhibition. These findings highlight the early evolution of UVR8 photoreceptor signaling in the green lineage to induce UV-B acclimation and protection. PMID:27020958

A review of the use of tanning beds as a dermatological treatment.

PubMed

Radack, Kyle P; Farhangian, Michael E; Anderson, Kathryn L; Feldman, Steven R

2015-03-01

In-office phototherapy is an effective treatment for many dermatologic conditions, however, many patients are unable to adhere to the rigorous travel and time commitments sometimes needed. Tanning bed facilities are nearly ubiquitous in modern society and could represent a more convenient means to obtain ultraviolet (UV) exposure when office phototherapy is not feasible. The purpose of this study was to review available evidence on the use of tanning facilities as a treatment for dermatologic conditions. PubMed was searched on February 2015 for "tanning beds" and "phototherapy", and with some dermatologic conditions sensitive to UV light, including "psoriasis", "mycosis fungoides", "acne", "atopic dermatitis" and "eczema". From there, further articles were found using the reference sections of the initial papers. A similar methodology was used with the Google Scholar search engine. Only articles in English and prospective studies were included in this review. We found studies validating the use of tanning facilities for psoriasis treatment. Use as a treatment option for atopic dermatitis, mycosis fungoides, acne, scleroderma, vitiligo, and pruritus, as well as other UV sensitive dermatoses, may also be beneficial. This study is limited by the lack of double-blind, placebo-controlled trials, long-term follow-up studies, and meta-analyses for tanning facility use in dermatologic phototherapy, and by the lack of standardization of both tanning facilities and exposure dosing. Unsupervised sun exposure is a standard recommendation for some patients to obtain phototherapy. Selected use of commercial tanning beds in the treatment of dermatologic conditions may be another useful and effective treatment for those patients with an inability to access office-based or home-based phototherapy.

Effects of Soybean Lipid Infusion on Unbound Free Fatty Acids and Unbound Bilirubin in Preterm Infants.

PubMed

Hegyi, Thomas; Kleinfeld, Alan; Huber, Andrew; Weinberger, Barry; Memon, Naureen; Shih, Weichung Joe; Carayannopoulos, Mary; Oh, William

2017-05-01

To assess the effects of a soybean lipid emulsion infusions on levels of unbound (free) bilirubin (Bf) and unbound free fatty acids (FFAu) as well as changes in Bf and total serum bilirubin (TSB) during phototherapy in infants born preterm. Ninety-seven infants born preterm (birth weight: 500-2000 g; gestational age: 23-34 weeks) were enrolled to investigate the effect of 0, 1, 2, and 3 g/kg/d of intralipid infusion on Bf and FFAu. Pre- and postphototherapy TSB, FFAu, and Bf also were analyzed in 91 infants to assess the effects of phototherapy. FFAu levels were measured with the fluorescent probe ADIFAB2 and Bf by the fluorescent Bf sensor BL22P1B11-Rh during intralipid infusion and at start and end of phototherapy. TSB and plasma albumin were measured by the diazo and bromcresol green techniques, respectively. Bilirubin-albumin dissociation constants were calculated based on Bf and plasma albumin. Bf and FFAu increased with increasing intralipid dosage across all gestational ages. TSB and Bf were correlated significantly when infants received 0 or 1 g/kg/d of intralipid but not at greater doses of intralipid (2 and 3 g/kg/d). Although phototherapy effectively reduced both TSB and Bf in the total phototherapy group (by 32% and 12%, respectively), it reduced TSB, but not Bf, in infants less than 28 weeks of gestation. Increasing intralipid doses result in increasing FFAu levels, which are associated with increased Bf independent of TSB. In infants born extremely preterm (<28 weeks of gestation), phototherapy effectively reduces TSB but not Bf. Copyright © 2016 Elsevier Inc. All rights reserved.

Utility of Decision Rules for Transcutaneous Bilirubin Measurements

PubMed Central

Burgos, Anthony E.; Flaherman, Valerie; Chung, Esther K.; Simpson, Elizabeth A.; Goyal, Neera K.; Von Kohorn, Isabelle; Dhepyasuwan, Niramol

2016-01-01

BACKGROUND: Transcutaneous bilirubin (TcB) meters are widely used for screening newborns for jaundice, with a total serum bilirubin (TSB) measurement indicated when the TcB value is classified as “positive” by using a decision rule. The goal of our study was to assess the clinical utility of 3 recommended TcB screening decision rules. METHODS: Paired TcB/TSB measurements were collected at 34 newborn nursery sites. At 27 sites (sample 1), newborns were routinely screened with a TcB measurement. For sample 2, sites that typically screen with TSB levels also obtained a TcB measurement for the study. Three decision rules to define a positive TcB measurement were evaluated: ≥75th percentile on the Bhutani nomogram, 70% of the phototherapy level, and within 3 mg/dL of the phototherapy threshold. The primary outcome was a TSB level at/above the phototherapy threshold. The rate of false-negative TcB screens and percentage of blood draws avoided were calculated for each decision rule. RESULTS: For sample 1, data were analyzed on 911 paired TcB-TSB measurements from a total of 8316 TcB measurements. False-negative rates were <10% with all decision rules; none identified all 31 newborns with a TSB level at/above the phototherapy threshold. The percentage of blood draws avoided ranged from 79.4% to 90.7%. In sample 2, each rule correctly identified all 8 newborns with TSB levels at/above the phototherapy threshold. CONCLUSIONS: Although all of the decision rules can be used effectively to screen newborns for jaundice, each will “miss” some infants with a TSB level at/above the phototherapy threshold. PMID:27244792

Randomized, blinded, controlled trial on effectiveness of photobiomodulation therapy and exercise training in the fibromyalgia treatment.

PubMed

da Silva, Mariana Moreira; Albertini, Regiane; de Tarso Camillo de Carvalho, Paulo; Leal-Junior, Ernesto Cesar Pinto; Bussadori, Sandra Kalil; Vieira, Stella Sousa; Bocalini, Danilo Sales; de Oliveira, Luis Vicente Franco; Grandinetti, Vanessa; Silva, José Antonio; Serra, Andrey Jorge

2018-02-01

This study evaluated the role of the phototherapy and exercise training (EXT) as well as the combined treatment in general symptoms, pain, and quality of life in women suffering from fibromyalgia (FM). A total of 160 women were enrolled and measures were carried out in two sets: it was sought to identify the acute effect for a single phototherapy and EXT session (Set 1); long-term effect (10 weeks) of the interventions (Set 2). Phototherapy irradiation was performed at 11 locations in their bodies, employing a cluster with nine diodes (one super-pulsed infrared 905 nm, four light-emitting diodes [LEDs] of 640 nm, and four LEDs of 875 nm, 39.3 J per location). Algometry and VAS instrument were applied to evaluate pain. The FM symptoms were evaluated with Fibromyalgia Impact Questionnaire (FIQ) and Research Diagnostic Criteria (RDC) instruments. Quality of life was assessed through SF-36 survey. Set 1: pain threshold was improved with the phototherapy, and EXT improved the pain threshold for temporomandibular joint (right and left body side) and occipital site (right body side). Set 2: there was improved pain threshold in several tender points with the phototherapy and EXT. There was an overlap of therapies to reduce the tender point numbers, anxiety, depression, fatigue, sleep, and difficulty sleeping on FIQ/RDC scores. Moreover, quality of life was improved with both therapies. The phototherapy and EXT improved the pain threshold in FM women. A more substantial effect was noticed for the combined therapy, in which pain relief was accomplished by improving VAS and FIQ scores as well as quality of life.

[Tl(III)(dota)](-): An Extraordinarily Robust Macrocyclic Complex.

PubMed

Fodor, Tamás; Bányai, István; Bényei, Attila; Platas-Iglesias, Carlos; Purgel, Mihály; Horváth, Gábor L; Zékány, László; Tircsó, Gyula; Tóth, Imre

2015-06-01

The X-ray structure of {C(NH2)3}[Tl(dota)]·H2O shows that the Tl(3+) ion is deeply buried in the macrocyclic cavity of the dota(4-) ligand (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate) with average Tl-N and Tl-O distances of 2.464 and 2.365 Å, respectively. The metal ion is directly coordinated to the eight donor atoms of the ligand, which results in a twisted square antiprismatic (TSAP') coordination around Tl(3+). A multinuclear (1)H, (13)C, and (205)Tl NMR study combined with DFT calculations confirmed the TSAP' structure of the complex in aqueous solution, which exists as the Λ(λλλλ)/Δ(δδδδ) enantiomeric pair. (205)Tl NMR spectroscopy allowed the protonation constant associated with the protonation of the complex according to [Tl(dota)](-) + H(+) ⇆ [Tl(Hdota)] to be determined, which turned out to be pK(H)Tl(dota) = 1.4 ± 0.1. [Tl(dota)](-) does not react with Br(-), even when using an excess of the anion, but it forms a weak mixed complex with cyanide, [Tl(dota)](-) + CN(-) ⇆ [Tl(dota)(CN)](2-), with an equilibrium constant of Kmix = 6.0 ± 0.8. The dissociation of the [Tl(dota)](-) complex was determined by UV-vis spectrophotometry under acidic conditions using a large excess of Br(-), and it was found to follow proton-assisted kinetics and to take place very slowly (∼10 days), even in 1 M HClO4, with the estimated half-life of the process being in the 10(9) h range at neutral pH. The solution dynamics of [Tl(dota)](-) were investigated using (13)C NMR spectroscopy and DFT calculations. The (13)C NMR spectra recorded at low temperature (272 K) point to C4 symmetry of the complex in solution, which averages to C4v as the temperature increases. This dynamic behavior was attributed to the Λ(λλλλ) ↔ Δ(δδδδ) enantiomerization process, which involves both the inversion of the macrocyclic unit and the rotation of the pendant arms. According to our calculations, the arm-rotation process limits the Λ(λλλλ) ↔ Δ(δδδδ) interconversion.

Telomere length differences between subcutaneous and visceral adipose tissue in humans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lakowa, Nicole; Trieu, Nhu; Flehmig, Gesine

Adipocyte hypertrophy and hyperplasia have been shown to be associated with shorter telomere length, which may reflect aging, altered cell proliferation and adipose tissue (AT) dysfunction. In individuals with obesity, differences in fat distribution and AT cellular composition may contribute to obesity related metabolic diseases. Here, we tested the hypotheses that telomere lengths (TL) are different between: (1) abdominal subcutaneous and omental fat depots, (2) superficial and deep abdominal subcutaneous AT (SAT), and (3) adipocytes and cells of the stromal vascular fraction (SVF). We further asked whether AT TL is related to age, anthropometric and metabolic traits. TL was analyzedmore » by quantitative PCR in total human genomic DNA isolated from paired subcutaneous and visceral AT of 47 lean and 50 obese individuals. In subgroups, we analyzed TL in isolated small and large adipocytes and SVF cells. We find significantly shorter TL in subcutaneous compared to visceral AT (P < 0.001) which is consistent in men and subgroups of lean and obese, and individuals with or without type 2 diabetes (T2D). Shorter TL in SAT is entirely due to shorter TL in the SVF compared to visceral AT (P < 0.01). SAT TL is most strongly correlated with age (r = −0.205, P < 0.05) and independently of age with HbA1c (r = −0.5, P < 0.05). We found significant TL differences between superficial SAT of lean and obese as well as between individuals with our without T2D, but not between the two layers of SAT. Our data indicate that fat depot differences in TL mainly reflect shorter TL of SVF cells. In addition, we found an age and BMI-independent relationship between shorter TL and HbA1c suggesting that chronic hyperglycemia may impair the regenerative capacity of AT more strongly than obesity alone. - Highlights: • Telomere lengths (TL) differ between fat depots mainly due to different lengths in SVF. • TL is not associated with gender, BMI and T2D. • The tendency for shorter TL in small versus large adipocytes suggests that small adipocytes represent a younger generation of adipocytes. • TLs of superficial subcutaneous adipose tissue are shorter in T2D patients compared to non-diabetic controls. • TL is not different between deep and superficial adipose tissue.« less

UVB-induced epidermal pigmentation in mice eyes with no contact lens wear and non-UVB blocking and UVB blocking contact lens wear.

PubMed

Hiramoto, Keiichi; Kobayashi, Hiromi; Yamate, Yurika; Ishii, Masamitsu; Sato, Takao; Inoue, Masayasu

2013-02-01

Irradiation by ultraviolet (UV) B is known to increase the number of Dopa-positive melanocytes in the skin. This study examines the effectiveness of a contact lens for the defense of UVB eye irradiation-induced pigmentation. A 2.5 kJ/m(2) dose of UVB radiation was delivered by a sunlamp to the eye of C57BL/6j male mice, and changes in the expression of Dopa-positive melanocytes in the epidermis and the plasma level of alpha-melanocyte-stimulating hormone (α-MSH) was analyzed. The degree of change in the Dopa-positive melanocytes expression was reduced by UVB blocking contact lens using mice given UVB irradiation to the eye. The plasma level of α-MSH increased in the C57BL/6j mice after irradiation to the eye, but there was no increase in the UVB blocking contact lens mice given UVB irradiation to the eye. Both the increase of the expression of Dopa-positive melanocytes and the plasma level of α-MSH were strongly suppressed by an alignment fitting UVB blocking contact lens and only a slightly suspended UVB blocking contact lens. In addition, these changes were successfully inhibited by a UVB blocking contact lens but not by a non-UVB blocking contact lens with a similar absorbance. These observations suggest that the UVB blocking contact lens inhibits the pigmentation of the epidermis in mice by suppressing of the α-MSH. Copyright © 2012 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Phototherapy of the newborn: a predictive model for the outcome.

PubMed

Ossamu Osaku, Nelson; Silverio Lopes, Heitor

2005-01-01

Jaundice in one of the most common problems of the newborn. In most cases, jaundice is considered a physiological transient situation, but sometimes it can lead to death or serious injuries for the survivors. For decades, phototherapy has been used as the main method for prevention and treatment of hyperbilirubinaemia of the newborn. This work aims at finding a predictive model for the decrement of blood bilirubin followed conventional phototherapy. Data from 90 patients were collected and used in the multiple regression method. A rigorous statistical analysis was done in order to guarantee a correct and valid model. The obtained model was able to explain 78% of the variation of the dependent variable We found that it is possible to predict the total sugar bilirubin of the patient under phototherapy by knowing its birth weight, bilirubin level at the beginning of treatment, duration of exposition, and irradiance. Besides, it is possible to infer the time necessary for a given decrement of bilirubin, under approximately constant irradiance.

Preparation and Characterization of UV Emitting Fluoride Phosphors for Phototherapy Lamps

NASA Astrophysics Data System (ADS)

Belsare, P. D.; Moharil, S. V.; Joshi, C. P.; Omanwar, S. K.

2011-10-01

The use of ultraviolet radiation for the treatment of various skin diseases is well known for long time. Phototherapy employs ultraviolet-blue radiation to cure skin diseases. The basis of phototherapy is believed to be the direct interaction of light of certain frequencies with tissue to cause a change in immune response. Currently dermatologists use UV lamps having specific emissions in UV region for treating various skin diseases. The treatment of skin diseases using artificial sources of UV radiation is now well established and more than 50 types of skin diseases are treated by phototherapy. This is an effective treatment for many skin disorders, such as psoriasis, vitiligo, ofujis disease, morphea , scleroderma, cutaneous T-cell lymphoma, lupus erythematosus, hyperbilirubinemia commonly known as infant jaundice, acne vulgaris, This paper reports photoluminescence properties of UV emitting fluoride phosphors prepared by wet chemical method. Emission characteristics of these phosphors are found similar to those of commercial UV lamp phosphors with comparable intensities. The usefulness of UV emitting fluoride phosphor is discussed in the paper.

Identification of low amount of irradiated spices (red pepper, garlic, ginger powder) with luminescence analysis

NASA Astrophysics Data System (ADS)

Kim, Byeong-Keun; Akram, Kashif; Kim, Cheong-Tae; Kang, Na-Roo; Lee, Jin-Won; Ryang, Jun-Hwan; Kwon, Joong-Ho

2012-08-01

For the identification of irradiated food, current analysis methods have limitations regarding presence and stability of radiation-induced markers. In this study, different spice blends with small quantity of different irradiated (0, 1 and 10 kGy) spice powders, such as red pepper, garlic or ginger, were investigated using PSL and TL techniques. In PSL-based screening analysis, the spice blends containing 10% of irradiated materials (1 or 10 kGy) were determined as intermediate or positive. In TL results, the blends containing 1% of 1 or 10 kGy-irradiated spices showed the typical TL glow curves that could be interpreted as positive. The blends with irradiated garlic powder provided more good results where identification was possible at 0.5% mixing of irradiated sample. However, the TL ratios of all spice blends were <0.1 and only TL glow curve shape and intensity may be used to discriminate the samples having irradiated component.

Phototherapy in skeletal muscle performance and recovery after exercise: effect of combination of super-pulsed laser and light-emitting diodes.

PubMed

Antonialli, Fernanda Colella; De Marchi, Thiago; Tomazoni, Shaiane Silva; Vanin, Adriane Aver; dos Santos Grandinetti, Vanessa; de Paiva, Paulo Roberto Vicente; Pinto, Henrique Dantas; Miranda, Eduardo Foschini; de Tarso Camillo de Carvalho, Paulo; Leal-Junior, Ernesto Cesar Pinto

2014-11-01

Recent studies with phototherapy have shown positive results in enhancement of performance and improvement of recovery when applied before exercise. However, several factors still remain unknown such as therapeutic windows, optimal treatment parameters, and effects of combination of different light sources (laser and LEDs). The aim of this study was to evaluate the effects of phototherapy with the combination of different light sources on skeletal muscle performance and post-exercise recovery, and to establish the optimal energy dose. A randomized, double-blinded, placebo-controlled trial with participation of 40 male healthy untrained volunteers was performed. A single phototherapy intervention was performed immediately after pre-exercise (baseline) maximum voluntary contraction (MVC) with a cluster of 12 diodes (4 of 905 nm lasers-0.3125 mW each, 4 of 875 nm LEDs-17.5 mW each, and 4 of 670 nm LEDs-15 mW each- manufactured by Multi Radiance Medical™) and dose of 10, 30, and 50 J or placebo in six sites of quadriceps. MVC, delayed onset muscle soreness (DOMS), and creatine kinase (CK) activity were analyzed. Assessments were performed before, 1 min, 1, 24, 48, 72, and 96 h after eccentric exercise protocol employed to induce fatigue. Phototherapy increased (p < 0.05) MVC was compared to placebo from immediately after to 96 h after exercise with 10 or 30 J doses (better results with 30 J dose). DOMS was significantly decreased compared to placebo (p < 0.05) with 30 J dose from 24 to 96 h after exercise, and with 50 J dose from immediately after to 96 h after exercise. CK activity was significantly decreased (p < 0.05) compared to placebo with all phototherapy doses from 1 to 96 h after exercise (except for 50 J dose at 96 h). Pre-exercise phototherapy with combination of low-level laser and LEDs, mainly with 30 J dose, significantly increases performance, decreases DOMS, and improves biochemical marker related to skeletal muscle damage.

UV-B exposure impairs resistance to infection by Trichinella spiralis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goettsch, W.; Garssen, J.; Deijns, A.

1994-03-01

To assess the possibility that increases in UV-B exposure on the earth's surface could lead to impaired resistance to several infectious diseases, we studied the effect of UV-B exposure on resistance against Trichinella spiralis. Wistar rats, orally infected with T. spiralis larvae, were exposed to suberythemal doses of UV-B radiation daily for 5 days at different time periods before or after infection. A significant increase in the number of Trichinella larvae was found in the carcasses of rats irradiated with UV-B between 6 and 10 days after infection. These data indicate that exposure to UV-B radiation suppresses the resistance tomore » a parasitic infection. We suggested that UV-B radiation especially suppresses cellular immune responses against these worms because specific IgM, IgG, and IgE titers were not significantly altered by UV-B exposure. These data indicate that UV-B irradiation plays a role in the course of infection with T. spiralis, which suggests that increases of UV-B exposure might also lead to problems with other infectious diseases and might affect vaccination because of the interaction of UV-B irradiation with memory T-cells. 38 refs., 3 figs., 1 tab.« less

Biology of Bilirubin Photoisomers.

PubMed

Hansen, Thor Willy Ruud

2016-06-01

Phototherapy is the main treatment for neonatal hyperbilirubinemia. In acute treatment of extreme hyperbilirubinemia, intensive phototherapy may have a role in 'detoxifying' the bilirubin molecule to more polar photoisomers, which should be less prone to crossing the blood-brain barrier, providing a 'brain-sparing' effect. This article reviews the biology of bilirubin isomers. Although there is evidence supporting the lower toxicity of bilirubin photoisomers, there are studies showing the opposite. There are methodologic weaknesses in most studies and better-designed experiments are needed. In an infant acutely threatened by bilirubin-induced brain damage, intensified phototherapy should be used expediently and aggressively. Copyright © 2016 Elsevier Inc. All rights reserved.

Irradiance of phototherapy equipment in maternity wards in Maceió.

PubMed

Ferreira, Anne Laura Costa; Nascimento, Renata Medeiros do; Veríssimo, Regina Célia Sales Santos

2009-01-01

The effectiveness of neonatal hyperbilirubinaemia treatment depends directly on the amount of energy emitted by light (irradiance). This cross-sectional study aimed to determine the irradiance of phototherapy equipment in maternity wards in Maceió, AL, Brazil. All equipment in use in the neonatal units in Maceió was included in the study, totaling 36 devices, except those in maintenance. The measurement of irradiance was carried out with a radiometer. We observed that 72.20% of the equipment presented efficient irradiance and 27.76% were inefficient. The conclusion is that the majority of phototherapy devices are emitting the minimum required irradiance for neonatal jaundice treatment.

Understanding Autoimmunity of Vitiligo and Alopecia Areata

PubMed Central

Rork, Jillian F.; Rashighi, Mehdi; Harris, John E.

2016-01-01

Purpose of review Vitiligo and alopecia areata are common, disfiguring skin diseases. Treatment options are limited and include non-targeted approaches such as corticosteroids, topical calcineurin inhibitors, narrow band UVB phototherapy, and other immune-modifying agents. The purpose of this article is to review shared, novel mechanisms between vitiligo and alopecia areata, as well as discuss how they inform the development of future targeted treatments. Recent findings Vitiligo and alopecia areata are both autoimmune diseases, and striking similarities in pathogenesis have been identified at the level of both the innate and adaptive immune system. Increased reactive oxygen species and high cellular stress level have been suggested as the initiating trigger of the innate immune system in both diseases, and genome-wide association studies have implicated risk alleles that influence both innate and adaptive immunity. Most importantly, mechanistic studies in mouse models of vitiligo and alopecia areata have specifically implicated an IFN-γ-driven immune response, including IFN-γ, IFN-γ-induced chemokines, and cytotoxic CD8+ T cells as the main drivers of disease pathogenesis. These recent discoveries may reveal an effective strategy to develop new treatments, and several proof-of-concept clinical studies support this hypothesis. Summary The identification of IFN-γ-driven immune signaling pathways has enabled discoveries of potential new treatments for vitiligo and alopecia areata, and supports initiation of larger clinical trials. PMID:27191524

Blackberry extract inhibits UVB-induced oxidative damage and inflammation through MAP kinases and NF-κB signaling pathways in SKH-1 mice skin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Divya, Sasidharan Padmaja; Wang, Xin; Pratheeshkumar, Poyil

Extensive exposure of solar ultraviolet-B (UVB) radiation to skin induces oxidative stress and inflammation that play a crucial role in the induction of skin cancer. Photochemoprevention with natural products represents a simple but very effective strategy for the management of cutaneous neoplasia. In this study, we investigated whether blackberry extract (BBE) reduces chronic inflammatory responses induced by UVB irradiation in SKH-1 hairless mice skin. Mice were exposed to UVB radiation (100 mJ/cm{sup 2}) on alternate days for 10 weeks, and BBE (10% and 20%) was applied topically a day before UVB exposure. Our results show that BBE suppressed UVB-induced hyperplasiamore » and reduced infiltration of inflammatory cells in the SKH-1 hairless mice skin. BBE treatment reduced glutathione (GSH) depletion, lipid peroxidation (LPO), and myeloperoxidase (MPO) in mouse skin by chronic UVB exposure. BBE significantly decreased the level of pro-inflammatory cytokines IL-6 and TNF-α in UVB-exposed skin. Likewise, UVB-induced inflammatory responses were diminished by BBE as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, BBE also reduced inflammatory mediators such as cyclooxygenase-2 (COX-2), prostaglandin E{sub 2} (PGE{sub 2}), and inducible nitric oxide synthase (iNOS) levels in UVB-exposed skin. Treatment with BBE inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mouse skin. Immunohistochemistry analysis revealed that topical application of BBE inhibited the expression of 8-oxo-7, 8-dihydro-2′-deoxyguanosine (8-oxodG), cyclobutane pyrimidine dimers (CPD), proliferating cell nuclear antigen (PCNA), and cyclin D1 in UVB-exposed skin. Collectively, these data indicate that BBE protects from UVB-induced oxidative damage and inflammation by modulating MAP kinase and NF-κB signaling pathways. - Highlights: • Blackberry extract inhibits UVB-induced glutathione depletion. • Blackberry extract inhibits UVB-induced lipid peroxidation. • Blackberry extract inhibits UVB-induced myeloperoxidase activity. • Blackberry extract diminishes UVB-induced inflammatory responses. • Blackberry extract prevents skin from oxidative damage and inflammation by UVB.« less

Cyanidin-3-glucoside inhibits UVB-induced oxidative damage and inflammation by regulating MAP kinase and NF-κB signaling pathways in SKH-1 hairless mice skin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pratheeshkumar, Poyil; Son, Young-Ok; Wang, Xin

Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicatemore » that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE{sub 2} and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2′-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways. - Highlights: • C3G inhibited UVB-induced oxidative damage and inflammation. • C3G inhibited UVB-induced COX-2, iNOS and PGE{sub 2} production. • C3G inhibited UVB-induced elevated proinflammatory cytokine level. • C3G inhibited UVB-induced p38 MAP kinase signaling. • C3G inhibited UVB-induced NF-κB activation.« less

Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice

PubMed Central

Lim, Jae-Youn; Kim, Ok-Kyung; Lee, Jeongmin; Lee, Min-Jae; Kang, Namgil

2014-01-01

BACKGROUND/OBJECTIVES Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. MATERIALS/METHODS Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). RESULTS The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. CONCLUSIONS Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression. PMID:25110559

Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice.

PubMed

Lim, Jae-Youn; Kim, Ok-Kyung; Lee, Jeongmin; Lee, Min-Jae; Kang, Namgil; Hwang, Jae-Kwan

2014-08-01

Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression.

Perception of solar UVB radiation by phytophagous insects: Behavioral responses and ecosystem implications

PubMed Central

Mazza, Carlos A.; Zavala, Jorge; Scopel, Ana L.; Ballaré, Carlos L.

1999-01-01

Most of our present knowledge about the impacts of solar UVB radiation on terrestrial ecosystems comes from studies with plants. Recently, the effects of UVB on the growth and survival of consumer species have begun to receive attention, but very little is known about UVB impacts on animal behavior. Here we report that manipulations of the flux of solar UVB received by field-grown soybean crops had large and consistent effects on the density of the thrips (Caliothrips phaseoli, Thysanoptera: Thripidae) populations that invaded the canopies, as well as on the amount of leaf damage caused by the insects. Solar UVB strongly reduced thrips herbivory. Thrips not only preferred leaves from plants that were not exposed to solar UVB over leaves from UVB-exposed plants in laboratory and field choice experiments, but they also appeared to directly sense and avoid exposure to solar UVB. Additional choice experiments showed that soybean leaf consumption by the late-season soybean worm Anticarsia gemmatalis (Lepidoptera: Noctuidae) was much less intense in leaves with even slight symptoms of an early thrips attack than in undamaged leaves. These experiments suggest that phytophagous insects can present direct and indirect behavioral responses to solar UVB. The indirect responses are mediated by changes in the plant host that are induced by UVB and, possibly, by other insects whose behavior is affected by UVB. PMID:9927679

Comparing the effect of clofibrate and phenobarbital on the newborns with hyperbilirubinemia

PubMed Central

Hamidi, Majid; Zamanzad, Behnam; Mesripour, Azadeh

2013-01-01

The aim of treating hyperbilirubinemia is preventing the serum bilirubin to reach neurotoxic levels, which is done by phototherapy or blood transfusion. However, pharmacological treatments still remain vague. Therefore the effects of adding either clofibrate or phenobarbital on treatment outcomes was evaluated in icteric non-hemolitic newborns. Ninety neonates were divided in three groups. Two groups were prescribed 100 mg/kg clofibrate or 5 mg/kg phenobarbital orally as single dose on arrival, in addition to phototherapy. The control group only received phototherapy. Serum bilirubin was evaluated at the reception and 12, 24, 48 and 72 hours after beginning of drug therapy. Total bilirubin levels decreased in treated groups compared with the control group in all samples taken (12, 24, 48 and 72 hours). Clofibrate effect in decreasing bilirubin level was more prominent (14 % and 32 % after 12 and 72 h respectively). In addition duration of hospitalization and length of phototherapy decreased in clofibrate and phenobarbital groups compared with control group (1.5, 2 days respectively, vs. 2.6 days). Therefore using clofibrate and phenobarbital in icteric neonates are supportive not only by decreasing the serum bilirubin level, but also by lessening the duration of hospitalization and phototherapy. Thus in addition to cost benefits for the patient these drugs can reduce the risks of transfusion, and clofibrate seems more promising in this regard. PMID:26417217

A dose-response model for the conventional phototherapy of the newborn.

PubMed

Osaku, Nelson Ossamu; Lopes, Heitor Silvério

2006-06-01

Jaundice of the newborn is a common problem as a consequence of the rapid increment of blood bilirubin in the first days of live. In most cases, it is considered a physiological transient situation, but unmanaged hyperbilirubinemia can lead to death or serious injuries for the survivors. For decades, phototherapy has been used as the main method for prevention and treatment of hyperbilirubinaemia of the newborn. This work aims at finding a predictive model for the decrement of blood bilirubin for patients submitted to conventional phototherapy. Data from the phototherapy of 90 term newborns were collected and used in a multiple regression method. A rigorous statistical analysis was done in order to guarantee a correct and valid model. The obtained model was able to explain 78% of the variation of the dependent variable. We show that it is possible to predict the total serum bilirubin of the patient under conventional phototherapy by knowing its birth weight, bilirubin level at the beginning of treatment and the radiant energy density (dose). Besides, it is possible to infer the time necessary for a given decrement of bilirubin, under approximately constant irradiance. Statistical analysis of the obtained model shows that it is valid for several ranges of birth weight, initial bilirubin level, and radiant energy density. It is expected that the proposed model can be useful in the clinical management of hyperbilirubinemia of the newborn.

Is phototherapy exposure associated with better or worse outcomes in 501–1000 gram birth weight infants?

PubMed Central

Hintz, Susan R.; Stevenson, David K.; Yao, Qing; Wong, Ronald J.; Das, Abhik; Van Meurs, Krisa P.; Morris, Brenda H.; Tyson, Jon E.; Oh, William; Poole, W. Kenneth; Phelps, Dale L.; McDavid, Georgia E.; Grisby, Cathy; Higgins, Rosemary D.

2012-01-01

Aim To compare risk-adjusted outcomes at 18–22 months corrected age for extremely low birth weight (ELBW) infants who never received phototherapy (NoPTx) to those who received any phototherapy (PTx) in the NICHD Neonatal Research Network randomized trial of Aggressive vs. Conservative Phototherapy. Methods Outcomes at 18–22 months corrected age included death, neurodevelopmental impairment (NDI), and Bayley Scales Mental Developmental Index (MDI). Regression models evaluated the independent association of PTx with adverse outcomes controlling for center and other potentially confounding variables. Results Of 1972 infants, 216 were NoPTx and 1756 were PTx. For the entire 501–1000 g BW cohort, PTx was not independently associated with death or NDI (OR 0.85, 95% CI 0.60 –1.20), death, or adverse neurodevelopmental endpoints. However, among infants 501–750 g BW, the rate of significant developmental impairment with MDI<50 was significantly higher for NoPTx (29%) than PTx (12%) (p=0.004). Conclusions Phototherapy did not appear to be independently associated with death or NDI for the overall ELBW group. Whether PTx increases mortality could not be excluded due to bias from deaths before reaching conservative treatment threshold. The higher rate of MDI<50 in the 501–750g BW NoPTx group is concerning, and consistent with NRN Trial results. PMID:21272067

Meta-Analysis of the Effect of Chest Shielding on Preventing Patent Ductus Arteriosus in Premature Infants.

PubMed

Mannan, Javed; Amin, Sanjiv B

2017-03-01

Objective  This study aims to perform a meta-analysis of randomized studies to evaluate if chest shielding during phototherapy is associated with decreased incidence of patent ductus arteriosus (PDA) in premature infants. Design/Methods  We used published guidelines for the meta-analysis of clinical trials. The search strategy included electronic searches of CINAHL, CENTRAL Cochrane Library, MEDLINE, PubMed, and abstracts presented at the Pediatric Academic Societies. Inclusion criteria were randomized controlled trials (RCTs), quasi-RCTs or cluster RCTs published in English and involving chest shielding during phototherapy in premature infants with PDA as an outcome. Exclusion criteria involved case reports, case series, and multiple publications from the same author. Heterogeneity testing using Q statistics was performed to evaluate the variance between studies. Results  Two RCTs met study criteria. There was heterogeneity (I 2 : 55.4%) between the two trials. Meta-analysis of RCTs using the random effect model demonstrated that chest shielding during phototherapy was associated with decreased incidence of PDA (odds ratio: 0.47, 95% confidence interval: 0.23-0.96). There was no publication bias on Eggers test. Heterogeneity was seen in gestational age, gender, prophylactic use of postnatal indomethacin, duration of phototherapy, and assessment of PDA. Conclusion  Chest shielding during phototherapy may be associated with decreased incidence of PDA among premature infants. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Implications of mycosporine-like amino acid and antioxidant defenses in UV-B radiation tolerance for the algae species Ptercladiella capillacea and Gelidium amansii.

PubMed

Lee, Tse-Min; Shiu, Chia-Tai

2009-02-01

Ultraviolet-B (UV-B) radiation (0.5, 1.0, 1.5, and 3.0Wm(-2)) induced higher H(2)O(2) production and lipid peroxidation in alga Gelidium amansii inhabiting in lower subtidal regions than upper subtidal alga Ptercladiella capillacea. Compared to G. amansii, mycosporine-like amino acid (MAA) concentration in P. capillacea was higher and can be increased by 0.5-1.0Wm(-2) UV-B, while carotenoid concentration was lower but also increased by 1.5-3.0Wm(-2) UV-B. UV-B increased ascorbate concentration, but to a higher degree in P. capillacea. UV-B decreased glutathione concentration, but to a higher degree in G. amansii. UV-B increased ascorbate peroxidase (APX) and glutathione reductase (GR) activities in P.capillacea but decreased them in G. amansii. UV-B increased superoxide dismutase and catalase activities, but to a higher degree in G. amansii. So, G. amansii suffered greater oxidative stress from UV-B radiation. P. capillacea can effectively reduce UV-B sensitivity by increasing sunscreen ability and antioxidant defense capacity.

Accumulation of flavonoids and related compounds in birch induced by UV-B irradiance.

PubMed

Lavola, Anu

1998-01-01

A growth chamber experiment was conducted to examine the effects of UV-B exposure (4.9 kJ m(-2) day(-1) of biologically effective UV-B, 280-320 nm) on shoot growth and secondary metabolite production in Betula pendula (Roth) and B. resinifera (Britt.) seedlings originating from environments in Finland, Germany and Alaska differing in solar UV-B radiation and climate. Neither shoot growth nor the composition of secondary metabolites was affected by UV-B irradiance, but the treatment induced significant changes in the amounts of individual secondary metabolites in leaves. Leaves of seedlings exposed to UV-B radiation contained higher concentrations of several flavonoids, condensed tannins and some hydroxycinnamic acids than leaves of control seedlings that received no UV-B radiation. At the population level, there was considerable variation in secondary metabolite responses to UV-B radiation: among populations, the induced response was most prominent in Alaskan populations, which were adapted to the lowest ambient UV-B radiation environment. I conclude that solar UV-B radiation plays an important role in the formation of secondary chemical characteristics in birch trees.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quesada, A.; Mouget, J.L.; Vincent, W.F.

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 wasmore » 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.« less

Leucocytes telomere length and breast cancer risk/ susceptibility: A case-control study.

PubMed

Pavanello, Sofia; Varesco, Liliana; Gismondi, Viviana; Bruzzi, Paolo; Bolognesi, Claudia

2018-01-01

Telomere length in peripheral blood leukocytes (PBL-TL) was proposed as a biomarker of cancer risk. Recent scientific evidence suggested PBL-TL plays a diverse role in different cancers. Inconsistent results were obtained on PBL-TL in relation to breast cancer risk and specifically to the presence of BRCA1 and BRCA2 mutations. The aim of the present case-control study was to analyse the correlation between family history of breast cancer or presence of a BRCA mutation and PBL-TL in the hypothesis that TL is a modifier of cancer risk. PBL-TL was measured using the real-time quantitative PCR method in DNA for 142 cases and 239 controls. All the women enrolled were characterized for cancer family history. A subgroup of 48 women were classified for the presence of a BRCA mutation. PBL-TL were summarized as means and standard deviations, and compared by standard analysis of variance. A multivariable Generalised Linear Model was fitted to the data with PBL-TL as the dependent variable, case/control status and presence of a BRCA/VUS mutation as factors, and age in 4 strata as a covariate. Age was significantly associated with decreasing PBL-TL in controls (p = 0.01), but not in BC cases. The telomere length is shorter in cases than in controls after adjusting for age. No effect on PBL-TL of BMI, smoke nor of the most common risk factors for breast cancer was observed. No association between PBL-TL and family history was detected both in BC cases and controls. In the multivariate model, no association was observed between BRCA mutation and decreased PBL-TL. A statistically significant interaction (p = 0.031) between case-control status and a BRCA-mutation/VUS was observed, but no effect was detected for the interaction of cancer status and BRCA or VUS. Our study fails to provide support to the hypothesis that PBL-TL is associated with the risk of hereditary BC, or that is a marker of inherited mutations in BRCA genes.

Leucocytes telomere length and breast cancer risk/ susceptibility: A case-control study

PubMed Central

Pavanello, Sofia; Varesco, Liliana; Gismondi, Viviana; Bruzzi, Paolo

2018-01-01

Background Telomere length in peripheral blood leukocytes (PBL-TL) was proposed as a biomarker of cancer risk. Recent scientific evidence suggested PBL-TL plays a diverse role in different cancers. Inconsistent results were obtained on PBL-TL in relation to breast cancer risk and specifically to the presence of BRCA1 and BRCA2 mutations. The aim of the present case-control study was to analyse the correlation between family history of breast cancer or presence of a BRCA mutation and PBL-TL in the hypothesis that TL is a modifier of cancer risk. Methods PBL-TL was measured using the real-time quantitative PCR method in DNA for 142 cases and 239 controls. All the women enrolled were characterized for cancer family history. A subgroup of 48 women were classified for the presence of a BRCA mutation. PBL-TL were summarized as means and standard deviations, and compared by standard analysis of variance. A multivariable Generalised Linear Model was fitted to the data with PBL-TL as the dependent variable, case/control status and presence of a BRCA/VUS mutation as factors, and age in 4 strata as a covariate. Results Age was significantly associated with decreasing PBL-TL in controls (p = 0.01), but not in BC cases. The telomere length is shorter in cases than in controls after adjusting for age. No effect on PBL-TL of BMI, smoke nor of the most common risk factors for breast cancer was observed. No association between PBL-TL and family history was detected both in BC cases and controls. In the multivariate model, no association was observed between BRCA mutation and decreased PBL-TL. A statistically significant interaction (p = 0.031) between case-control status and a BRCA-mutation/VUS was observed, but no effect was detected for the interaction of cancer status and BRCA or VUS. Conclusion Our study fails to provide support to the hypothesis that PBL-TL is associated with the risk of hereditary BC, or that is a marker of inherited mutations in BRCA genes. PMID:29782524

Effect of enhanced UV-B radiation on pollen quantity, quality, and seed yield in Brassica rapa (Brassicaceae)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demchik, S.M.; Day, T.A.

Three experiments examined the influence of ultraviolet-B radiation (UV-B; 280-320 nm) exposure on reproduction in Brassica rapa (Brassicacaeae). Plants were grown in a greenhouse under three biologically effective UV-B levels that stimulated either an ambient stratospheric ozone level (control), 16% ({open_quotes}low enhanced{close_quotes}), or 32% ({open_quotes}high enhanced{close_quotes}) ozone depletion levels at Morgantown, WV, USA in mid-March. In the first experiment,pollen production and viability per flower were reduced by {approx}50% under both enhanced UV-B levels relative to ambient controls. While plants under high-enhanced UV-B produced over 40% more flowers than plants under the two lower UV-B treatments, whole-plant production of viable pollenmore » was reduced under low-enhanced UV-B to 34% of ambient controls. In the second experiment, the influence of source-plant UV-B exposure on in vitro pollen from plants was examined and whether source-plant UV-B exposure influenced in vitro pollen germination and viability. Pollen from plants under both enhanced-UV-B was reduced from 65 to 18%. Viability of the pollen from plants grown under both enhanced UV-B treatments was reduced to a much lesser extent: only from {approx}43 to 22%. Thus, ambient source-plant pollen was more sensitive to enhanced UV-B levels to fertilize plants growing under ambient-UV-B levels, and assessed subsequent seed production and germination. Seed abortion rates were higher in plants pollinated with pollen from the enhanced UV-B treatments, than from ambient UV-B. Despite this, seed yield (number and mass) per plant was similar, regardless of the UV-B exposure of their pollen source. Our findings demonstrate that enhanced UV-B levels associated with springtime ozone depletion events have the capacity to substantially reduce viable pollen production, and could ultimately reduce reproductive success of B. rapa. 37 refs., 4 figs., 2 tabs.« less

Latitudinal variation in ambient UV-B radiation is an important determinant of Lolium perenne forage production, quality, and digestibility

PubMed Central

Comont, David; Winters, Ana; Gomez, Leonardo D; McQueen-Mason, Simon J; Gwynn-Jones, Dylan

2013-01-01

Few studies to date have considered the responses of agriculturally important forage grasses to UV-B radiation. Yet grasses such as Lolium perenne have a wide current distribution, representing exposure to a significant variation in ambient UV-B. The current study investigated the responses of L. perenne (cv. AberDart) to a simulated latitudinal gradient of UV-B exposure, representing biologically effective UV-B doses at simulated 70, 60, 50, 40, and 30° N latitudes. Aspects of growth, soluble compounds, and digestibility were assessed, and results are discussed in relation to UV-B effects on forage properties and the implications for livestock and bio-ethanol production. Aboveground biomass production was reduced by approximately 12.67% with every 1 kJ m–2 day–1 increase in biologically weighted UV-B. As a result, plants grown in the highest UV-B treatment had a total biomass of just 13.7% of controls. Total flavonoids were increased by approximately 76% by all UV-B treatments, while hydroxycinnamic acids increased in proportion to the UV-B dose. Conversely, the digestibility of the aboveground biomass and concentrations of soluble fructans were reduced by UV-B exposure, although soluble sucrose, glucose, and fructose concentrations were unaffected. These results highlight the capacity for UV-B to directly affect forage productivity and chemistry, with negative consequences for digestibility and bioethanol production. Results emphasize the need for future development and distribution of L. perenne varieties to take UV-B irradiance into consideration. PMID:23580749

Effects of UV-B Radiation and Periodic Desiccation on the Morphogenesis of the Edible Terrestrial Cyanobacterium Nostoc flagelliforme

PubMed Central

Feng, Yan-Na; Zhang, Zhong-Chun; Feng, Jun-Li

2012-01-01

The terrestrial cyanobacterium Nostoc flagelliforme Berk. et M. A. Curtis has been a popular food and herbal ingredient for hundreds of years. To meet great market demand and protect the local ecosystem, for decades researchers have tried to cultivate N. flagelliforme but have failed to get macroscopic filamentous thalli. In this study, single trichomes with 50 to 200 vegetative cells were induced from free-living cells by low light and used to investigate the morphogenesis of N. flagelliforme under low UV-B radiation and periodic desiccation. Low-fluence-rate UV-B (0.1 W m−2) did not inhibit trichome growth; however, it significantly increased the synthesis of extracellular polysaccharides and mycosporine-like amino acids and promoted sheath formation outside the trichomes. Under low UV-B radiation, single trichomes developed into filamentous thalli more than 1 cm long after 28 days of cultivation, most of which grew separately in liquid BG11 medium. With periodic desiccation treatment, the single trichomes formed flat or banded thalli that grew up to 2 cm long after 3 months on solid BG11 medium. When trichomes were cultivated on solid BG11 medium with alternate treatments of low UV-B and periodic desiccation, dark and scraggly filamentous thalli that grew up to about 3 cm in length after 40 days were obtained. In addition, the cultivation of trichomes on nitrogen-deficient solid BG11 medium (BG110) suggested that nitrogen availability could affect the color and lubricity of newly developed thalli. This study provides promising techniques for artificial cultivation of N. flagelliforme in the future. PMID:22865081

Solar ultraviolet-B radiation increases phenolic content and ferric reducing antioxidant power in Avena sativa.

PubMed

Ruhland, Christopher T; Fogal, Mitchell J; Buyarski, Christopher R; Krna, Matthew A

2007-06-29

We examined the influence of solar ultraviolet-B radiation (UV-B; 280-320 nm) on the maximum photochemical efficiency of photosystem II (F(v)/F(m)), bulk-soluble phenolic concentrations, ferric-reducing antioxidant power (FRAP) and growth of Avena sativa. Treatments involved placing filters on frames over potted plants that reduced levels of biologically effective UV-B by either 71% (reduced UV-B) or by 19% (near-ambient UV-B) over the 52 day experiment (04 July-25 August 2002). Plants growing under near-ambient UV-B had 38% less total biomass than those under reduced UV-B. The reduction in biomass was mainly the result of a 24% lower leaf elongation rate, resulting in shorter leaves and less total leaf area than plants under reduced UV-B. In addition, plants growing under near-ambient UV-B had up to 17% lower F(v)/F(m) values early in the experiment, and this effect declined with plant age. Concentrations of bulk-soluble phenolics and FRAP values were 17 and 24% higher under near-ambient UV-B than under reduced UV-B, respectively. There was a positive relationship between bulk-soluble phenolic concentrations and FRAP values. There were no UV-B effects on concentrations of carotenoids (carotenes + xanthophylls).

Distribution of boreal toad populations in relation to estimated UV-B dose in Glacier National Park, Montana, USA

USGS Publications Warehouse

Hossack, B.R.; Diamond, S.A.; Corn, P.S.

2006-01-01

A recent increase in ultraviolet B radiation is one hypothesis advanced to explain suspected or documented declines of the boreal toad (Bufo boreas Baird and Girard, 1852) across much of the western USA, where some experiments have shown ambient UV-B can reduce embryo survival. We examined B. boreas occupancy relative to daily UV-B dose at 172 potential breeding sites in Glacier National Park, Montana, to assess whether UV-B limits the distribution of toads. Dose estimates were based on ground-level UV-B data and the effects of elevation, local topographic and vegetative features, and attenuation in the water column. We also examined temporal trends in surface UV-B and spring snowpack to determine whether populations are likely to have experienced increased UV-B exposure in recent decades. We found no support for the hypothesis that UV-B limits the distribution of populations in the park, even when we analyzed high-elevation ponds separately. Instead, toads were more likely to breed in water bodies with higher estimated UV-B doses. The lack of a detectable trend in surface UV-B since 1979, combined with earlier snow melt in the region and increasing forest density at high elevations, suggests B. boreas embryos and larvae likely have not experienced increased UV-B.

Impact of UV-B exposure on amphibian embryos: linking species physiology and oviposition behaviour

PubMed Central

Palen, Wendy J; Williamson, Craig E; Clauser, Aaron A; Schindler, Daniel E

2005-01-01

Increasing ultraviolet-B radiation (UV-B) has recently captured the attention of ecologists as a key environmental stressor. Certain species may be particularly vulnerable as a result of either high natural exposure to UV-B or limited physiological capacity to withstand it. UV-B sensitivity has been examined at the cellular and individual level for a wide variety of taxa, but estimates of exposure to UV-B in natural systems are lacking and predictions of large-scale impacts are therefore limited. Here, we combine data on the physiological sensitivity to UV-B and patterns of field exposure across sites for embryos of several well-studied US Pacific Northwest amphibian species. We find substantial differences among species' physiological abilities to withstand UV-B and in the level of UV-B exposure of embryos in the field. More specifically, we find that species with the highest physiological sensitivity to UV-B are those with the lowest field exposures as a function of the location of embryos and the UV-B attenuation properties of water at each site. These results also suggest that conclusions made about species' vulnerability to UV-B in the absence of information on field exposures may often be misleading. PMID:16024386

UV-B Radiation Induces Root Bending Through the Flavonoid-Mediated Auxin Pathway in Arabidopsis.

PubMed

Wan, Jinpeng; Zhang, Ping; Wang, Ruling; Sun, Liangliang; Wang, Wenying; Zhou, Huakun; Xu, Jin

2018-01-01

Ultraviolet (UV)-B radiation-induced root bending has been reported; however, the underlying mechanisms largely remain unclear. Here, we investigate whether and how auxin and flavonoids are involved in UV-B radiation-induced root bending in Arabidopsis using physiological, pharmacological, and genetic approaches. UV-B radiation modulated the direction of root growth by decreasing IAA biosynthesis and affecting auxin distribution in the root tips, where reduced auxin accumulation and asymmetric auxin distribution were observed. UV-B radiation increased the distribution of auxin on the nonradiated side of the root tips, promoting growth and causing root bending. Further analysis indicated that UV-B induced an asymmetric accumulation of flavonoids; this pathway is involved in modulating the accumulation and asymmetric distribution of auxin in root tips and the subsequent redirection of root growth by altering the distribution of auxin carriers in response to UV-B radiation. Taken together, our results indicate that UV-B radiation-induced root bending occurred through a flavonoid-mediated phototropic response to UV-B radiation.

UV-B Radiation Induces Root Bending Through the Flavonoid-Mediated Auxin Pathway in Arabidopsis

PubMed Central

Wan, Jinpeng; Zhang, Ping; Wang, Ruling; Sun, Liangliang; Wang, Wenying; Zhou, Huakun; Xu, Jin

2018-01-01

Ultraviolet (UV)-B radiation-induced root bending has been reported; however, the underlying mechanisms largely remain unclear. Here, we investigate whether and how auxin and flavonoids are involved in UV-B radiation-induced root bending in Arabidopsis using physiological, pharmacological, and genetic approaches. UV-B radiation modulated the direction of root growth by decreasing IAA biosynthesis and affecting auxin distribution in the root tips, where reduced auxin accumulation and asymmetric auxin distribution were observed. UV-B radiation increased the distribution of auxin on the nonradiated side of the root tips, promoting growth and causing root bending. Further analysis indicated that UV-B induced an asymmetric accumulation of flavonoids; this pathway is involved in modulating the accumulation and asymmetric distribution of auxin in root tips and the subsequent redirection of root growth by altering the distribution of auxin carriers in response to UV-B radiation. Taken together, our results indicate that UV-B radiation-induced root bending occurred through a flavonoid-mediated phototropic response to UV-B radiation. PMID:29868074

Solar Ultraviolet-B Radiation Affects Seedling Emergence, DNA Integrity, Plant Morphology, Growth Rate, and Attractiveness to Herbivore Insects in Datura ferox.

PubMed Central

Ballare, C. L.; Scopel, A. L.; Stapleton, A. E.; Yanovsky, M. J.

1996-01-01

To study functional relationships between the effects of solar ultraviolet-B radiation (UV-B) on different aspects of the physiology of a wild plant, we carried out exclusion experiments in the field with the summer annual Datura ferox L. Solar UV-B incident over Buenos Aires reduced daytime seedling emergence, inhibited stem elongation and leaf expansion, and tended to reduce biomass accumulation during early growth. However, UV-B had no effect on calculated net assimilation rate. Using a monoclonal antibody specific to the cyclobutane-pyrimidine dimer (CPD), we found that plants receiving full sunlight had more CPDs per unit of DNA than plants shielded from solar UV-B, but the positive correlation between UV-B and CPD burden tended to level off at high (near solar) UV-B levels. At our field site, Datura plants were consumed by leaf beetles (Coleoptera), and the proportion of plants attacked by insects declined with the amount of UV-B received during growth. Field experiments showed that plant exposure to solar UV-B reduced the likelihood of leaf beetle attack by one-half. Our results highlight the complexities associated with scaling plant responses to solar UV-B, because they show: (a) a lack of correspondence between UV-B effects on net assimilation rate and whole-plant growth rate, (b) nonlinear UV-B dose-response curves, and (c) UV-B effects of plant attractiveness to natural herbivores. PMID:12226382

The UVR8 UV-B Photoreceptor: Perception, Signaling and Response

PubMed Central

Tilbrook, Kimberley; Arongaus, Adriana B.; Binkert, Melanie; Heijde, Marc; Yin, Ruohe; Ulm, Roman

2013-01-01

Ultraviolet-B radiation (UV-B) is an intrinsic part of sunlight that is accompanied by significant biological effects. Plants are able to perceive UV-B using the UV-B photoreceptor UVR8 which is linked to a specific molecular signaling pathway and leads to UV-B acclimation. Herein we review the biological process in plants from initial UV-B perception and signal transduction through to the known UV-B responses that promote survival in sunlight. The UVR8 UV-B photoreceptor exists as a homodimer that instantly monomerises upon UV-B absorption via specific intrinsic tryptophans which act as UV-B chromophores. The UVR8 monomer interacts with COP1, an E3 ubiquitin ligase, initiating a molecular signaling pathway that leads to gene expression changes. This signaling output leads to UVR8-dependent responses including UV-B-induced photomorphogenesis and the accumulation of UV-B-absorbing flavonols. Negative feedback regulation of the pathway is provided by the WD40-repeat proteins RUP1 and RUP2, which facilitate UVR8 redimerization, disrupting the UVR8-COP1 interaction. Despite rapid advancements in the field of recent years, further components of UVR8 UV-B signaling are constantly emerging, and the precise interplay of these and the established players UVR8, COP1, RUP1, RUP2 and HY5 needs to be defined. UVR8 UV-B signaling represents our further understanding of how plants are able to sense their light environment and adjust their growth accordingly. PMID:23864838

Linalool prevents oxidative stress activated protein kinases in single UVB-exposed human skin cells

PubMed Central

Govindasamy, Kanimozhi; Ramasamy, Karthikeyan; Muthusamy, Ganesan; Shanmugam, Mohana; Thangaiyan, Radhiga; Robert, Beaulah Mary; Ponniresan, Veeramani kandan; Rathinaraj, Pierson

2017-01-01

Ultraviolet-B radiation (285–320 nm) elicits a number of cellular signaling elements. We investigated the preventive effect of linalool, a natural monoterpene, against UVB-induced oxidative imbalance, activation of mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) signaling in HDFa cells. We observed that linalool treatment (30 μM) prevented acute UVB-irradiation (20 mJ/cm2) mediated loss of activities of antioxidant enzymes in HDFa cells. The comet assay results illustrate that linalool significantly prevents UVB-mediated 8-deoxy guanosine formation (oxidative DNA damage) rather than UVB-induced cyclobutane pyrimidine (CPD) formation. This might be due to its ability to prevent UVB-induced ROS formation and to restore the oxidative imbalance of cells. This has been reflected in UVB-induced overexpression of MAPK and NF-κB signaling. We observed that linalool inhibited UVB-induced phosphorylation of ERK1, JNK and p38 proteins of MAPK family. Linalool inhibited UVB-induced activation of NF-κB/p65 by activating IκBa. We further observed that UVB-induced expression of TNF-α, IL6, IL-10, MMP-2 and MMP-9 was modulated by linalool treatment in HDFa cells. Thus, linalool protects the human skin cells from the oxidative damages of UVB radiation and modulates MAPK and NF-κB signaling in HDFa cells. The present findings substantiate that linalool may act as a photoprotective agent against UVB-induced skin damages. PMID:28467450

Thermoluminescence of nanocrystalline CaSO{sub 4}: Dy for gamma dosimetry and calculation of trapping parameters using deconvolution method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mandlik, Nandkumar, E-mail: ntmandlik@gmail.com; Patil, B. J.; Bhoraskar, V. N.

2014-04-24

Nanorods of CaSO{sub 4}: Dy having diameter 20 nm and length 200 nm have been synthesized by the chemical coprecipitation method. These samples were irradiated with gamma radiation for the dose varying from 0.1 Gy to 50 kGy and their TL characteristics have been studied. TL dose response shows a linear behavior up to 5 kGy and further saturates with increase in the dose. A Computerized Glow Curve Deconvolution (CGCD) program was used for the analysis of TL glow curves. Trapping parameters for various peaks have been calculated by using CGCD program.

Thermoluminescence of nanocrystalline CaSO4: Dy for gamma dosimetry and calculation of trapping parameters using deconvolution method

NASA Astrophysics Data System (ADS)

Mandlik, Nandkumar; Patil, B. J.; Bhoraskar, V. N.; Sahare, P. D.; Dhole, S. D.

2014-04-01

Nanorods of CaSO4: Dy having diameter 20 nm and length 200 nm have been synthesized by the chemical coprecipitation method. These samples were irradiated with gamma radiation for the dose varying from 0.1 Gy to 50 kGy and their TL characteristics have been studied. TL dose response shows a linear behavior up to 5 kGy and further saturates with increase in the dose. A Computerized Glow Curve Deconvolution (CGCD) program was used for the analysis of TL glow curves. Trapping parameters for various peaks have been calculated by using CGCD program.

Chest shielding for prevention of a haemodynamically significant patent ductus arteriosus in preterm infants receiving phototherapy.

PubMed

Bhola, Kavita; Foster, Jann P; Osborn, David A

2015-11-03

Patent ductus arteriosus (PDA) is associated with mortality and morbidity in preterm infants. Phototherapy is a common treatment for jaundice in preterm infants. However, phototherapy has been associated with failure of closure of the ductus arteriosus in preterm infants. To determine if chest shielding of preterm infants receiving phototherapy reduces the incidence of clinically and/or haemodynamically significant PDA and reduces morbidity secondary to PDA. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library; 2015, Issue 3), MEDLINE, EMBASE, CINAHL, previous reviews, cross-references, abstracts, proceedings of scientific meetings, and trial registries through March 2015. Randomised controlled trials (RCTs), cluster-RCTs, or quasi-RCTs of chest shielding during phototherapy compared to sham shielding or no shielding for the prevention of a haemodynamically or clinically significant PDA in preterm infants. Three review authors independently assessed studies for eligibility and quality and extracted data. We defined a clinically significant PDA as the presence of a PDA with clinical signs of an effect on organ function attributable to the ductus arteriosus. We defined a haemodynamically significant PDA as clinical and/or echocardiographic signs of a significant ductus arteriosus effect on blood flow. We included two small trials enrolling very preterm infants (Rosenfeld 1986; Travadi 2006). We assessed both as at high risk of bias. No study reported clinically significant PDA, defined as the presence of a PDA with clinical symptoms or signs attributable to the effect of a ductus arteriosus on organ function. Rosenfeld 1986 reported a non-significant reduction in haemodynamically significant PDA with left atrial to aortic root ratio greater than 1.2 (risk ratio (RR) 0.23, 95% confidence interval (CI) 0.05 to 1.01; 74 infants) but a statistically significant risk difference (RD -0.18, 95% CI -0.34 to -0.03; number needed to treat for an additional beneficial outcome (NNTB) 5, 95% CI 3 to 33). Rosenfeld 1986 reported a significant reduction in PDA detected by murmur (RR 0.50, 95% CI 0.29 to 0.88; RD -0.30, 95% CI -0.52 to -0.08; NNTB 3, 95% CI 2 to 12; 74 infants). Rosenfeld 1986 reported a significant reduction in treatment with indomethacin (RR 0.12, 95% CI 0.02 to 0.88; RD -0.21, 95% CI -0.35 to -0.06; NNTB 5, 95% CI 3 to 17; 74 infants), and only one infant had a ductal ligation in the no-shield group. There were no other significant outcomes, including mortality to discharge or 28 days, days in oxygen, days on mechanical ventilation, days in hospital, intraventricular haemorrhage, retinopathy of prematurity, or exchange transfusion. The available evidence is very low quality and insufficient to assess the safety or efficacy of chest shield during phototherapy for prevention of PDA in preterm infants. Further trials of chest shielding are warranted, particularly in settings where infants are not receiving prophylactic or early echocardiographic targeted cyclo-oxygenase inhibitors for PDA.

Comparison of UV-B measurements performed with a Brewer spectrophotometer and a new UVB-1 broad band detector

NASA Technical Reports Server (NTRS)

Bais, Alkiviadis F.; Zerefos, Christos S.; Meleti, Charicleia; Ziomas, Ioannis C.

1994-01-01

Measurements of the UV-B erythemal dose, based on solar spectra acquired with a Brewer spectrophotometer at Thessaloniki, Greece, are compared to measurements performed with the recently introduced, by the Yankee Environmental Systems, (Robertson type) broad band solar UV-B detector. The spectral response function of this detector, when applied to the Brewer spectral UV-B measurements, results in remarkably comparable estimates of the erythemal UV-B dose. The two instruments provide similar information on the UV-B dose when they are cross-examined under a variety of meteorological and atmospheric conditions and over the a large range of solar zenith angles and total ozone.

Photo-protection by 3-bromo-4, 5-dihydroxybenzaldehyde against ultraviolet B-induced oxidative stress in human keratinocytes.

PubMed

Hyun, Yu Jae; Piao, Mei Jing; Zhang, Rui; Choi, Yung Hyun; Chae, Sungwook; Hyun, Jin Won

2012-09-01

Exposure of the skin to ultraviolet B (UVB) radiation leads to epidermal damage and the generation of reactive oxygen species (ROS) in skin cells, including keratinocytes. Therefore, the photo-protective effect of 3-bromo-4, 5-dihydroxybenzaldehyde (BDB) against UVB was assessed in human HaCaT keratinocytes exposed to UVB radiation in vitro. BDB restored cell viability, which decreased upon exposure to UVB radiation. BDB exhibited scavenging activity against 1, 1-diphenyl-2-picrylhydrazyl radicals, intracellular ROS induced by hydrogen peroxide (H(2)O(2)) or UVB radiation, the superoxide anion generated by the xanthine/xanthine oxidase system, and the hydroxyl radical generated by the Fenton reaction (FeSO(4)+H(2)O(2)). Moreover, BDB absorbed UVB and decreased injury resulting from UVB-induced oxidative stress to lipids, proteins and DNA. Finally, BDB reduced UVB-induced apoptosis, as exemplified by fewer apoptotic bodies and a reduction in DNA fragmentation. Taken together, these results suggest that BDB protects human keratinocytes against UVB-induced oxidative stress by scavenging ROS and absorbing UVB rays, thereby reducing injury to cellular components. Copyright © 2012 Elsevier Inc. All rights reserved.

Ultraviolet B preconditioning enhances the hair growth-promoting effects of adipose-derived stem cells via generation of reactive oxygen species.

PubMed

Jeong, Yun-Mi; Sung, Young Kwan; Kim, Wang-Kyun; Kim, Ji Hye; Kwack, Mi Hee; Yoon, Insoo; Kim, Dae-Duk; Sung, Jong-Hyuk

2013-01-01

Hypoxia induces the survival and regenerative potential of adipose-derived stem cells (ASCs), but there are tremendous needs to find alternative methods for ASC preconditioning. Therefore, this work investigated: (1) the ability of low-dose ultraviolet B (UVB) radiation to stimulate the survival, migration, and tube-forming activity of ASCs in vitro; (2) the ability of UVB preconditioning to enhance the hair growth-promoting capacity of ASCs in vivo; and (3) the mechanism of action for ASC stimulation by UVB. Although high-dose UVB decreased the proliferation of ASCs, low-dose (10 or 20 mJ/cm(2)) treatment increased their survival, migration, and tube-forming activity. In addition, low-dose UVB upregulated the expression of ASC-derived growth factors, and a culture medium conditioned by UVB-irradiated ASCs increased the proliferation of dermal papilla and outer root sheet cells. Notably, injection of UVB-preconditioned ASCs into C(3)H/HeN mice significantly induced the telogen-to-anagen transition and increased new hair weight in vivo. UVB treatment significantly increased the generation of reactive oxygen species (ROS) in cultured ASCs, and inhibition of ROS generation by diphenyleneiodonium chloride (DPI) significantly attenuated UVB-induced ASC stimulation. Furthermore, NADPH oxidase 4 (Nox4) expression was induced in ASCs by UVB irradiation, and Nox4 silencing by small interfering RNA, like DPI, significantly reduced UVB-induced ROS generation. These results suggest that the primary involvement of ROS generation in UVB-mediated ASC stimulation occurs via the Nox4 enzyme. This is the first indication that a low dose of UVB radiation and/or the control of ROS generation could potentially be incorporated into a novel ASC preconditioning method for hair regeneration.

Silibinin inhibits ultraviolet B radiation-induced DNA-damage and apoptosis by enhancing interleukin-12 expression in JB6 cells and SKH-1 hairless mouse skin.

PubMed

Narayanapillai, Sreekanth; Agarwal, Chapla; Deep, Gagan; Agarwal, Rajesh

2014-06-01

Recent studies have demonstrated silibinin efficacy against ultraviolet B (UVB)-induced skin carcinogenesis via different mechanisms in cell lines and animal models; however, its role in regulating interleukin-12 (IL-12), an immunomodulatory cytokine that reduces UVB-induced DNA damage and apoptosis, is not known. Here, we report that UVB irradiation causes caspase 3 and PARP cleavage and apoptosis, and addition of recombinant IL-12 or silibinin immediately after UVB significantly protects UVB-induced apoptosis in JB6 cells. IL-12 antibody-mediated blocking of IL-12 activity compromised the protective effects of both IL-12 and silibinin. Both silibinin and IL-12 also accelerated the repair of UVB-caused cyclobutane-pyrimidine dimers (CPDs) in JB6 cells. Additional studies confirmed that indeed silibinin causes a significant increase in IL-12 levels in UVB-irradiated JB6 cells as well as in mouse skin epidermis, and that similar to cell-culture findings, silibinin topical application immediately after UVB exposure causes a strong protection against UVB-induced TUNEL positive cells in epidermis possibly through a significantly accelerated repair of UVB-caused CPDs. Together, these findings for the first time provide an important insight regarding the pharmacological mechanism wherein silibinin induces endogenous IL-12 in its efficacy against UVB-caused skin damages. In view of the fact that an enhanced endogenous IL-12 level could effectively remove UVB-caused DNA damage and associated skin cancer, our findings suggest that the use of silibinin in UVB-damaged human skin would also be a practical and translational strategy to manage solar radiation-caused skin damages as well as skin cancer. © 2013 Wiley Periodicals, Inc.

Distribution patterns of lentic-breeding amphibians in relation to ultraviolet radiation exposure in western North America

USGS Publications Warehouse

Adams, Michael J.; Hossack, B.R.; Knapp, R.A.; Corn, P.S.; Diamond, S.A.; Trenham, P.C.; Fagre, D.B.

2005-01-01

An increase in ultraviolet-B (UV-B) radiation has been posited to be a potential factor in the decline of some amphibian population. This hypothesis has received support from laboratory and field experiments showing that current levels of UV-B can cause embryo mortality in some species, but little research has addressed whether UV-B is influencing the distribution of amphibian populations. We compared patterns of amphibian presence to site-specific estimates of UV-B dose at 683 ponds and lakes in Glacier, Olympic, and Sequoia–Kings Canyon National Parks. All three parks are located in western North America, a region with a concentration of documented amphibian declines. Site-specific daily UV-B dose was estimated using modeled and field-collected data to incorporate the effects of elevation, landscape, and water-column dissolved organic carbon. Of the eight species we examined (Ambystoma gracile, Ambystoma macrodactylum, Bufo boreas, Pseudacris regilla, Rana cascadae, Rana leuteiventris, Rana muscosa, Taricha granulosa), two species (T. granulosa and A. macrodactylum) had quadratic relationships with UV-B that could have resulted from negative UV-B effects. Both species were most likely to occur at moderate UV-B levels. Ambystoma macrodactylum showed this pattern only in Glacier National Park. Occurrence of A. macrodactylum increased as UV-B increased in Olympic National Park despite UV-B levels similar to those recorded in Glacier. We also found marginal support for a negative association with UV-B for P. regilla in one of the two parks where it occurred. We did not find evidence of a negative UV-B effect for any other species. Much more work is still needed to determine whether UV-B, either alone or in concert with other factors, is causing widespread population losses in amphibians.

Development of UV-B screening compounds in response to variation in ambient levels of UV-B radiation

NASA Astrophysics Data System (ADS)

Sullivan, Joe H.; Xu, Chenping; Gao, Wei; Slusser, James R.

2005-08-01

The induction of UV-B screening compounds in response to exposure to UV-B radiation is a commonly reported response and is generally considered to be an adaptive response of plants for protection from UVinduced damage. However, a number of questions remain to be answered including the importance of qualitative and localization differences among species in providing protection, indirect consequences of changes in leaf secondary chemistry on ecological processes and the dose response of metabolite accumulation. In this study we utilized UV monitoring data provided on site by the USDA UV-B Monitoring and Research Program to monitor the changes in UV-screening compounds in soybeans under a range of UV-B levels due to natural variation in ambient UV-B radiation. Soybean cultivars Essex, Clark and Clark-magenta, an isoline of Clark that produces minimal levels of flavonols, were grown beneath shelters covered either with polyester to block most UV-B radiation or teflon which is nearly transparent in the UV range and harvested at regular intervals for pigment and protein analysis. Daily levels of weighted UV-B varied from <1 to >7 kJ m-2. Increases in UV-screening compounds showed a positive dose response to UV-B radiation in all cultivars with Essex showing the steepest dose response. UV-A also induced screening compounds in all species The hydroxycinnimates of the magenta isoline showed a steep dose response to UV-A and a rather constant (non dose specific) but small additional increment in response to UV-B. The Clark isoline, which produced primarily the flavonol quercetin, showed a dose response to UV-B intermediate between that of Clark-magenta and Essex. All three cultivars show similar tolerance to UV-B in field conditions indicating that UV-induced pigment production is adequate to protect them from excessive UV-B damage.

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.

PubMed

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.

Role of root UV-B sensing in Arabidopsis early seedling development.

PubMed

Tong, Hongyun; Leasure, Colin D; Hou, Xuewen; Yuen, Gigi; Briggs, Winslow; He, Zheng-Hui

2008-12-30

All sun-exposed organisms are affected by UV-B [(UVB) 280-320 nm], an integral part of sunlight. UVB can cause stresses or act as a developmental signal depending on its fluence levels. In plants, the mechanism by which high-fluence-rate UVB causes damages and activates DNA-repair systems has been extensively studied. However, little is known about how nondamaging low-fluence-rate UVB is perceived to regulate plant morphogenesis and development. Here, we report the identification of an Arabidopsis mutant, root UVB sensitive 1 (rus1), whose primary root is hypersensitive to very low-fluence-rate (VLF) UVB. Under standard growth-chamber fluorescent white light, rus1 displays stunted root growth and fails to form postembryonic leaves. Experiments with different monochromatic light sources showed that rus1 phenotypes can be rescued if the seedlings are allowed to grow in light conditions with minimum UVB. We determined that roots, not other organs, perceive the UVB signal. Genetic and molecular analyses confirmed that the root light-sensitive phenotypes are independent of all other known plant photoreceptors. Three rus1 alleles have been identified and characterized. A map-based approach was used to identify the RUS1 locus. RUS1 encodes a protein that contains DUF647 (domain of unknown function 647), a domain highly conserved in eukaryotes. Our results demonstrate a root VLF UVB-sensing mechanism that is involved in Arabidopsis early seedling morphogenesis and development.

Isoprene emission aids recovery of photosynthetic performance in transgenic Nicotiana tabacum following high intensity acute UV-B exposure.

PubMed

Centritto, Mauro; Haworth, Matthew; Marino, Giovanni; Pallozzi, Emanuele; Tsonev, Tsonko; Velikova, Violeta; Nogues, Isabel; Loreto, Francesco

2014-09-01

Isoprene emission by terrestrial plants is believed to play a role in mitigating the effects of abiotic stress on photosynthesis. Ultraviolet-B light (UV-B) induces damage to the photosynthetic apparatus of plants, but the role of isoprene in UV-B tolerance is poorly understood. To investigate this putative protective role, we exposed non-emitting (NE) control and transgenic isoprene emitting (IE) Nicotiana tabacum (tobacco) plants to high intensity UV-B exposure. Methanol emissions increased with UV-B intensity, indicating oxidative damage. However, isoprene emission was unaffected during exposure to UV-B radiation, but declined in the 48 h following UV-B treatment at the highest UV-B intensities of 9 and 15 Wm(-2). Photosynthesis and the performance of photosystem II (PSII) declined to similar extents in IE and NE plants following UV-B exposure, suggesting that isoprene emission did not ameliorate the immediate impact of UV-B on photosynthesis. However, after the stress, photosynthesis and PSII recovered in IE plants, which maintained isoprene formation, but not in NE plants. Recovery of IE plants was also associated with elevated antioxidant levels and cycling; suggesting that both isoprene formation and antioxidant systems contributed to reinstating the integrity and functionality of cellular membranes and photosynthesis following exposure to excessive levels of UV-B radiation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The effects of different UV-B radiation intensities on morphological and biochemical characteristics in Ocimum basilicum L.

PubMed

Sakalauskaitė, Jurga; Viskelis, Pranas; Dambrauskienė, Edita; Sakalauskienė, Sandra; Samuolienė, Giedrė; Brazaitytė, Aušra; Duchovskis, Pavelas; Urbonavičienė, Dalia

2013-04-01

The effects of short-term ultraviolet B (UV-B) irradiation on sweet basil (Ocimum basilicum L. cv. Cinnamon) plants at the 3-4 leaf pair and flowering stages were examined in controlled environment growth chambers. Plants were exposed to 0 (reference), 2 and 4 kJ UV-B m(-2) day(-1) over 7 days. Exposure of basil plants to supplementary UV-B light resulted in increased assimilating leaf area, fresh biomass and dry biomass. Stimulation of physiological functions in young basil plants under either applied UV-B dose resulted in increased total chlorophyll content but no marked variation in carotenoid content. At the flowering stage the chlorophyll and carotenoid contents of basil were affected by supplementary UV-B radiation, decreasing with enhanced UV-B exposure. Both total antioxidant activity (2,2-diphenyl-1-picrylhydrazyl free radical assay) and total phenolic compound content were increased by UV-B light supplementation. Young and mature basil plants differed in their ascorbic acid content, which was dependent on UV-B dose and plant age. UV-B radiation resulted in decreased nitrate content in young basil plants (3-4 leaf pair stage). These results indicate that the application of short-exposure UV-B radiation beneficially influenced both growth parameters and biochemical constituents in young and mature basil plants. © 2012 Society of Chemical Industry.

Tanning beds as an alternative for psoriasis when office-based phototherapy is not accessible.

PubMed

Yentzer, Brad A; Feldman, Steven R

2009-01-01

Many systemic therapies for psoriasis have significant toxicities. Office-based phototherapy is not always practical for many patients. We present a case report and review of using a tanning bed in conjunction with low-dose acitretin as an alternative treatment for moderate to severe plaque psoriasis.

Hydration and transparency of the rabbit cornea irradiated with UVB-doses of 0.25 J/cm(2) and 0.5 J/cm(2) compared with equivalent UVB radiation exposure reaching the human cornea from sunlight.

PubMed

Cejka, Cestmír; Ardan, Taras; Sirc, Jakub; Michálek, Jiří; Beneš, Jiří; Brůnová, Blanka; Rosina, Jozef

2011-07-01

Exposure of the cornea to UV radiation from sunlight evokes intraocular inflammation, photokeratitis. Photokeratitis is caused by UVB radiation. It is accompanied by changes of corneal hydration and light absorption. The aim of this study was to examine the effect of two UVB doses on corneal optics in rabbits and to compare these UVB doses with the equivalent exposure of UVB radiation reaching the human cornea from sunlight. Rabbit corneas were irradiated with a daily UVB dose of 0.25 J/cm(2) or 0.5 J/cm(2) for 4 days. One day after finishing the irradiations the rabbits were sacrificed and corneal light absorption measured using our spectrophotometrical method. Corneal hydration was examined using an ultrasonic Pachymeter every experimental day before the irradiation procedure and the last day before sacrificing the animals. Changes in corneal optics appeared after the repeated exposure of the cornea to a UVB dose of 0.25 J/ cm(2) and massively increased after the repeated exposure of the cornea to a UVB dose of 0.5 J/cm(2). The first significant changes in corneal hydration appeared after a single exposure of the cornea to a UVB dose of 0.25 J/cm(2). Changes in corneal hydration appeared after the exposure of the rabbit cornea to a single UVB dose equivalent to 2.6 hours of solar UVB radiation reaching the human cornea, as measured by UVB sensors embedded in the eyes of mannequin heads facing the sun on a beach at noon in July. Repeated exposure of the rabbit cornea to the same UVB dose evoked profound changes in corneal optics. Although comparison of experimental and outdoor conditions are only approximate, the results in rabbits point to the danger for the human eye from UVB radiation when short stays in sunlight are repeated for several consecutive days without UV protection.

Dose-Response Effect of Sunlight on Vitamin D2 Production in Agaricus bisporus Mushrooms.

PubMed

Urbain, Paul; Jakobsen, Jette

2015-09-23

The dose response effect of UV-B irradiation from sunlight on vitamin D2 content of sliced Agaricus bisporus (white button mushroom) during the process of sun-drying was investigated.Real-time UV-B and UV-A data were obtained using a high-performance spectroradiometer. During the first hour of sunlight exposure, the vitamin D2 content of the mushrooms increased in a linear manner, with concentrations increasing from 0.1 μg/g up to 3.9 ± 0.8 μg/g dry weight (DW). At the subsequent two measurements one and 3 h later, respectively, a plateau was reached. Two hours of additional exposure triggered a significant decline in vitamin D2 content. After just 15 min of sun exposure and an UV-B dose of 0.13 J/cm(2), the vitamin D2 content increased significantly to 2.2 ± 0.5 μg/g DW (P < 0.0001), which is equivalent to 17.6 μg (704 IU) vitamin D2 per 100 g of fresh mushrooms and comparable to levels found in fatty fish like the Atlantic salmon.

Association of UV radiation with multiple sclerosis prevalence and sex ratio in France.

PubMed

Orton, S-M; Wald, L; Confavreux, C; Vukusic, S; Krohn, J P; Ramagopalan, S V; Herrera, B M; Sadovnick, A D; Ebers, G C

2011-02-01

French farmers and their families constitute an informative population to study multiple sclerosis (MS) prevalence and related epidemiology. We carried out an ecological study to evaluate the association of MS prevalence and ultraviolet (UV) radiation, a candidate climatologic risk factor. Mean annual and winter (December-March) UVB irradiation values were systematically compared to MS prevalence rates in corresponding regions of France. UVB data were obtained from the solar radiation database (SoDa) service and prevalence rates from previously published data on 2,667 MS cases registered with the national farmer health insurance system, Mutualité Sociale Agricole (MSA). Pearson correlation was used to examine the relationship of annual and winter UVB values with MS prevalence. Male and female prevalence were also analyzed separately. Linear regression was used to test for interaction of annual and winter UVB with sex in predicting MS prevalence. There was a strong association between MS prevalence and annual mean UVB irradiation (r = -0.80, p < 0.001) and average winter UVB (r = -0.87, p < 0.001). Both female (r = -0.76, p < 0.001) and male (r = -0.46, p = 0.032) prevalence rates were correlated with annual UVB. Regression modeling showed that the effect of UVB on prevalence rates differed by sex; the interaction effect was significant for both annual UVB (p = 0.003) and winter UVB (p = 0.002). The findings suggest that regional UVB radiation is predictive of corresponding MS prevalence rates and supports the hypothesis that sunlight exposure influences MS risk. The evidence also supports a potential role for gender-specific effects of UVB exposure.

Protective mechanisms and acclimation to solar ultraviolet-B radiation in Oenothera stricta

NASA Technical Reports Server (NTRS)

Robberecht, R.; Caldwell, M. M.

1981-01-01

Plant adaptations ameliorating or repairing the damaging effects of ultraviolet-B (UV-B) radiation on plant tissue were investigated. The degree of phenotype plasticity in UV protective mechanisms and acclimation in relation to the natural solar UV-B radiation flux and in an enhanced UV-B irradiance environment was also examined. Mechanisms by which plants avoid radiation, adaptations altering the path of radiation incident on the leaf, and repair processes were considered. Attenuation of UV-B by tissues, UV-B irradiation into the leaf, and the effects of UV-B on photosynthesis were investigated.

Optical characteristics of natural waters protect amphibians from UV-B in the U.S. Pacific Northwest

USGS Publications Warehouse

Palen, Wendy J.; Schindler, David E.; Adams, Michael J.; Pearl, Christopher A.; Bury, R. Bruce; Diamond, S.A.

2002-01-01

Increased exposure to ultraviolet-B (UV-B) radiation has been proposed as a major environmental stressor leading to global amphibian declines. Prior experimental evidence from the U.S. Pacific Northwest (PNW) indicating the acute embryonic sensitivity of at least four amphibian species to UV-B has been central to the literature about amphibian decline. However, these results have not been expanded to address population-scale effects and natural landscape variation in UV-B transparency of water at amphibian breeding sites: both necessary links to assess the importance of UV-B for amphibian declines. We quantified the UV-B transparency of 136 potential amphibian breeding sites to establish the pattern of UV-B exposure across two montane regions in the PNW. Our data suggest that 85% of sites are naturally protected by dissolved organic matter in pond water, and that only a fraction of breeding sites are expected to experience UV-B intensities exceeding levels associated with elevated egg mortality. Thus, the spectral characteristics of natural waters likely mediate the physiological effects of UV-B on amphibian eggs in all but the clearest waters. These data imply that UV-B is unlikely to cause broad amphibian declines across the landscape of the American Northwest.

The changes in quality ingredients of Qi chrysanthemum flowers treated with elevated UV-B radiation at different growth stages.

PubMed

Yao, Xiaoqin; Chu, Jianzhou; He, Xueli; Ma, Chunhui; Han, Chao; Shen, Haiyu

2015-05-01

The paper mainly reported the changes in quality ingredients of Qi chrysanthemum flowers treated with elevated UV-B radiation at different growth stages. The experiment included two levels of UV-B radiation (ambient UV-B, a 10% increase in ambient UV-B). Elevated UV-B radiation was carried out for 10-days during seedling, vigorous growth, bud and flower stages of Qi chrysanthemum, respectively. Elevated UV-B treatments applied during four development stages did not significantly affect flower yield, the rate of superoxide radical production and malondialdehyde concentration in flowers, while increased free amino acid concentration. The amino acid concentration induced by elevated UV-B radiation applied during bud stage was higher than that during the other stages. Elevated UV-B radiation applied during vigorous growth (except for flavone), bud and flower stages of chrysanthemum significantly increased hydrogen peroxide concentration, phenylalanine ammonia lyase enzyme activity, vitamin C, chlorogenic acid and flavone concentrations in flowers. These results suggested that active and nutritional ingredients in flowers of chrysanthemum could be increased by elevated UV-B radiation applied during the later growth stages of chrysanthemum. The paper supplied a simple and environmental-friendly method to improve quality of medicinal plants. Copyright © 2015 Elsevier B.V. All rights reserved.

UVB Radiation Delays Tribolium castaneum Metamorphosis by Influencing Ecdysteroid Metabolism.

PubMed

Sang, Wen; Yu, Lin; He, Li; Ma, Wei-Hua; Zhu, Zhi-Hui; Zhu, Fen; Wang, Xiao-Ping; Lei, Chao-Liang

2016-01-01

Ultraviolet B (UVB) radiation is an important environmental factor. It is generally known that UVB exhibits high genotoxicity due to causing DNA damage, potentially leading to skin carcinogenesis and aging in mammals. However, little is known about the effects of UVB on the development and metamorphosis of insects, which are the most abundant terrestrial animals. In the present study, we performed dose-response analyses of the effects UVB irradiation on Tribolium castaneum metamorphosis, assessed the function of the T. castaneum prothoracicotropic hormone gene (Trcptth), and analyzed ecdysteroid pathway gene expression profile and ecdysterone titers post-UVB irradiation. The results showed that UVB not only caused death of T. castaneum larvae, but also delayed larval-pupal metamorphosis and reduced the size and emergence rate of pupae. In addition, we verified the function of Trcptth, which is responsible for regulating metamorphosis. It was also found that the expression profiles of Trcptth as well as ecdysteroidogenesis and response genes were influenced by UVB radiation. Therefore, a disturbance pulse of ecdysteroid may be involved in delaying development under exposure to irradiation. To our knowledge, this is the first report indicating that UVB can influence the metamorphosis of insects. This study will contribute to a better understanding of the impact of UVB on signaling mechanisms in insect metamorphosis.

Reproductive, morphological, and phytochemical responses of Arabidopsis thaliana ecotypes to enhanced UV-B radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trumbull, V.L.; McCloud, E.S.; Paige, K.N.

1994-06-01

Two ecotypes of Arabidopsis thaliana, collected from Libya and Norway, were grown in the greenhouse under. UV-B doses of 0 and 10.5 kJ m[sup [minus]2] UV-B[sub BE]. The high UV-B dose simulated midsummer ambient conditions over Libya and a 40% reduction in stratospheric ozone over Norway. The Libyan ectotype, which originated from latitudes where solar UV-B is high, showed no UV-B induced damage to plant growth. However the Norwegian ecotype, which originated from latitudes where solar UV-B is low, showed a significant reduction in plant height, inflorescence weight, and rosette weight in response to enhanced UV-B. Although fruit and seedmore » number for both ecotypes were unaffected by enhanced UV-B radiation the germination success of the seeds harvested from the irradiated Norwegian plants were significantly reduced. The two ecotypes also differed with respect to their accumulation of kaempferol, a putative UV-B protective filter. The Libyan ecotype increased kaempferol concentration by 38% over the 0 kJ treatment whereas the Norwegian ecotype increased by only 15%. These data suggest that, for these ecotypes, variation in UV-B sensitivity may be explained by the differential induction of UV-absorbing leaf pigments.« less

Measurement of metabolite variations and analysis of related gene expression in Chinese liquorice (Glycyrrhiza uralensis) plants under UV-B irradiation.

PubMed

Zhang, Xiao; Ding, Xiaoli; Ji, Yaxi; Wang, Shouchuang; Chen, Yingying; Luo, Jie; Shen, Yingbai; Peng, Li

2018-04-18

Plants respond to UV-B irradiation (280-315 nm wavelength) via elaborate metabolic regulatory mechanisms that help them adapt to this stress. To investigate the metabolic response of the medicinal herb Chinese liquorice (Glycyrrhiza uralensis) to UV-B irradiation, we performed liquid chromatography tandem mass spectrometry (LC-MS/MS)-based metabolomic analysis, combined with analysis of differentially expressed genes in the leaves of plants exposed to UV-B irradiation at various time points. Fifty-four metabolites, primarily amino acids and flavonoids, exhibited changes in levels after the UV-B treatment. The amino acid metabolism was altered by UV-B irradiation: the Asp family pathway was activated and closely correlated to Glu. Some amino acids appeared to be converted into antioxidants such as γ-aminobutyric acid and glutathione. Hierarchical clustering analysis revealed that various flavonoids with characteristic groups were induced by UV-B. In particular, the levels of some ortho-dihydroxylated B-ring flavonoids, which might function as scavengers of reactive oxygen species, increased in response to UV-B treatment. In general, unigenes encoding key enzymes involved in amino acid metabolism and flavonoid biosynthesis were upregulated by UV-B irradiation. These findings lay the foundation for further analysis of the mechanism underlying the response of G. uralensis to UV-B irradiation.

UV-B susceptibility and photoreactivation in embryonic development of the two-spotted spider mite, Tetranychus urticae.

PubMed

Yoshioka, Yoshio; Gotoh, Tetsuo; Suzuki, Takeshi

2018-05-14

Developmental errors are often induced in the embryos of many organisms by environmental stress. Ultraviolet-B radiation (UV-B) is one of the most serious environmental stressors in embryonic development. Here, we investigated susceptibility to UV-B (0.5 kJ m -2 ) in embryos of the two-spotted spider mite, Tetranychus urticae, to examine the potential use of UV-B in control of this important agricultural pest worldwide. Peak susceptibility to UV-B (0% hatchability) was found in T. urticae eggs 36-48 h after oviposition at 25 °C, which coincides with the stages of morphogenesis forming the germ band and initial limb primordia. However, hatchability recovered to ~ 80% when eggs irradiated with UV-B were subsequently exposed to visible radiation (VIS) at 10.2 kJ m -2 , driving photoreactivation (the photoenzymatic repair of DNA damage). The recovery effect decreased to 40-70% hatchability, depending on the embryonic developmental stage, when VIS irradiation was delayed for 4 h after the end of exposure to UV-B. Thus UV-B damage to T. urticae embryos is critical, particularly in the early stages of morphogenesis, and photoreactivation functions to mitigate UV-B damage, even in the susceptible stages, but immediate VIS irradiation is needed after exposure to UV-B. These findings suggest that nighttime irradiation with UV-B can effectively kill T. urticae eggs without subsequent photoreactivation and may be useful in the physical control of this species.

Effects of UV-B irradiation on isoforms of antioxidant enzymes and their activities in red alga Grateloupia filicina (Rhodophyta)

NASA Astrophysics Data System (ADS)

Zhao, Jiqiang; Li, Lixia

2014-11-01

Macroalgae in a littoral zone are inevitably exposed to UV-B irradiance. We analyzed the effects of UV-B on isoenzyme patterns and activities of superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), and ascorbate peroxidase (APX) of red algae Grateloupia filicina (Lamour.) C. Agardh. The activities of SOD, CAT, and APX changed in response to UV-B in a time- and dose-dependent manner. POX activity increased significantly under all three UV-B treatments. The enzymatic assay showed three distinct bands of SODI (Mn-SOD), SODII (Fe-SOD), and SODIII (CuZn-SOD) under a low (Luv) and medium (Muv) dose of UV-B irradiation, while SODI and SODIII activities decreased significantly when exposed to a high dose of UV-B irradiation (Huv). The activity of POX isoenzymes increased significantly after exposure to UV-B, which is consistent with the total activity. In addition, a clear decrease in activity of CATIV was detected in response to all the three doses of UV treatments. Some bands of APX isoenzyme were also clearly influenced by UV-B irradiation. Correspondingly, the daily growth rate declined under all the three exposure doses, and was especially significant under Muv and Huv treatments. These data suggest that, although the protection mechanisms of antioxidant defense system are partly inducible by UV-B to prevent the damage, G. filicina has incomplete tolerance to higher UV-B irradiation stress.

Telomere length, ATM mutation status and cancer risk in Ataxia-Telangiectasia families.

PubMed

Renault, Anne-Laure; Mebirouk, Noura; Cavaciuti, Eve; Le Gal, Dorothée; Lecarpentier, Julie; d'Enghien, Catherine Dubois; Laugé, Anthony; Dondon, Marie-Gabrielle; Labbé, Martine; Lesca, Gaetan; Leroux, Dominique; Gladieff, Laurence; Adenis, Claude; Faivre, Laurence; Gilbert-Dussardier, Brigitte; Lortholary, Alain; Fricker, Jean-Pierre; Dahan, Karin; Bay, Jacques-Olivier; Longy, Michel; Buecher, Bruno; Janin, Nicolas; Zattara, Hélène; Berthet, Pascaline; Combès, Audrey; Coupier, Isabelle; Hall, Janet; Stoppa-Lyonnet, Dominique; Andrieu, Nadine; Lesueur, Fabienne

2017-10-01

Recent studies have linked constitutive telomere length (TL) to aging-related diseases including cancer at different sites. ATM participates in the signaling of telomere erosion, and inherited mutations in ATM have been associated with increased risk of cancer, particularly breast cancer. The goal of this study was to investigate whether carriage of an ATM mutation and TL interplay to modify cancer risk in ataxia-telangiectasia (A-T) families.The study population consisted of 284 heterozygous ATM mutation carriers (HetAT) and 174 non-carriers (non-HetAT) from 103 A-T families. Forty-eight HetAT and 14 non-HetAT individuals had cancer, among them 25 HetAT and 6 non-HetAT were diagnosed after blood sample collection. We measured mean TL using a quantitative PCR assay and genotyped seven single-nucleotide polymorphisms (SNPs) recurrently associated with TL in large population-based studies.HetAT individuals were at increased risk of cancer (OR = 2.3, 95%CI = 1.2-4.4, P = 0.01), and particularly of breast cancer for women (OR = 2.9, 95%CI = 1.2-7.1, P = 0.02), in comparison to their non-HetAT relatives. HetAT individuals had longer telomeres than non-HetAT individuals (P = 0.0008) but TL was not associated with cancer risk, and no significant interaction was observed between ATM mutation status and TL. Furthermore, rs9257445 (ZNF311) was associated with TL in HetAT subjects and rs6060627 (BCL2L1) modified cancer risk in HetAT and non-HetAT women.Our findings suggest that carriage of an ATM mutation impacts on the age-related TL shortening and that TL per se is not related to cancer risk in ATM carriers. TL measurement alone is not a good marker for predicting cancer risk in A-T families. © The Author 2017. Published by Oxford University Press.

Analysis of thunder and lightning frequency in the Belgrade area in Serbia in the period 1975 - 2009

NASA Astrophysics Data System (ADS)

Todorovich, N.; Vujovic, D.

2010-09-01

The analysis included observations (non-instrumental data) about the thunder and lightning (TL) on Belgrade Meteorological Observatory (latitude 44°48´N, longitude 20°28´E, h=132 m) in the period 1975-2009. The data about the duration (in minutes) by dates were analyzed. The results confirmed already known fact that the TL are most frequent in June. There is a slight increasing trend of TL duration since the mid-eighties. The results of the daily distribution confirmed the basic finding that the TL frequency is higher in the afternoon and the evening hours when two distinctive peak noticed: first of about 17 hours and second about 21 and 22 hours (UTC +1), with the minimum in the morning hours. The annual number of days with TL has the similar distribution in the reporting period as like the annual sum of the duration in minutes. There is a slight increasing trend of days with TL from the mid-eighties. The month with the extreme number of days with TL is June. The most interesting result of analysis is the distribution of the number of days with TL by calendar days. Maximum is in late June and early July, the central date is June 28. In addition to the primary maximum, there are several maximum more in the form of group of several days. Such periods we might call quasi-singularities. In addition to the main period June 27 - July 01, the most important periods and dates (quasi-singularities) are April 24, April 30 - May 2, May 16 - May 22, June 7 - June 17, July 7, July 12-July 14, August 4, August 8 - August 11 and August 28 - September 1. The most notable long period with low frequency of days with TL is second half of July. It is evident that the number of days with TL rapidly increases after April 23 and rapidly reduced after September 2.

Anthropogenic changes in the surface all-sky UV-B radiation through 1850-2005 simulated by an Earth system model

NASA Astrophysics Data System (ADS)

Watanabe, S.; Takemura, T.; Sudo, K.; Yokohata, T.; Kawase, H.

2012-06-01

The historical anthropogenic change in the surface all-sky UV-B (solar ultraviolet: 280-315 nm) radiation through 1850-2005 is evaluated using an Earth system model. Responses of UV-B dose to anthropogenic changes in ozone and aerosols are separately evaluated using a series of historical simulations including/excluding these changes. Increases in these air pollutants cause reductions in UV-B transmittance, which occur gradually/rapidly before/after 1950 in and downwind of industrial and deforestation regions. Furthermore, changes in ozone transport in the lower stratosphere, which is induced by increasing greenhouse gas concentrations, increase ozone concentration in the extratropical upper troposphere and lower stratosphere. These transient changes work to decrease the amount of UV-B reaching the Earth's surface, counteracting the well-known effect increasing UV-B due to stratospheric ozone depletion, which developed rapidly after ca. 1980. As a consequence, the surface UV-B radiation change between 1850 and 2000 is negative in the tropics and NH extratropics and positive in the SH extratropics. Comparing the contributions of ozone and aerosol changes to the UV-B change, the transient change in ozone absorption of UV-B mainly determines the total change in the surface UV-B radiation at most locations. On the other hand, the aerosol direct and indirect effects on UV-B play an equally important role to that of ozone in the NH mid-latitudes and tropics. A typical example is East Asia (25° N-60° N and 120° E-150° E), where the effect of aerosols (ca. 70%) dominates the total UV-B change.

Anthropogenic changes in the surface all-sky UV-B radiation through 1850-2005 simulated by an Earth system model

NASA Astrophysics Data System (ADS)

Watanabe, S.; Takemura, T.; Sudo, K.; Yokohata, T.; Kawase, H.

2012-02-01

The historical anthropogenic change in the surface all-sky UV-B (solar ultraviolet: 280-315 nm) radiation through 1850-2005 is evaluated using an Earth system model. Responses of UV-B dose to anthropogenic changes in ozone and aerosols are separately evaluated using a series of historical simulations including/excluding these changes. Increases in these air pollutants cause reductions in UV-B transmittance, which occur gradually/rapidly before/after 1950 in and downwind of industrial and deforestation regions. Furthermore, changes in ozone transport in the lower stratosphere, which is induced by increasing greenhouse gas concentrations, increase ozone concentration in the extratropical upper troposphere and lower stratosphere. These transient changes work to decrease the amount of UV-B reaching the Earth's surface, counteracting the well-known effect increasing UV-B due to stratospheric ozone depletion, which developed rapidly after ca. 1980. As a consequence, the surface all-sky UV-B radiation change between 1850 and 2000 is negative in the tropics and NH extratropics and positive in the SH extratropics. Comparing the contributions of ozone and aerosol changes to the UV-B change, the transient change in ozone absorption of UV-B mainly determines the total change in the surface all-sky UV-B radiation at most locations. On the other hand, the aerosol direct and indirect effects on UV-B play an equally important role to that of ozone in the NH mid-latitudes and tropics. A typical example is East Asia (25° N-60° N and 120° E-150° E), where the effect of aerosols (ca. 70%) dominates the total UV-B change.

UV-blocking spectacle lens protects against UV-induced decline of visual performance.

PubMed

Liou, Jyh-Cheng; Teng, Mei-Ching; Tsai, Yun-Shan; Lin, En-Chieh; Chen, Bo-Yie

2015-01-01

Excessive exposure to sunlight may be a risk factor for ocular diseases and reduced visual performance. This study was designed to examine the ability of an ultraviolet (UV)-blocking spectacle lens to prevent visual acuity decline and ocular surface disorders in a mouse model of UVB-induced photokeratitis. Mice were divided into 4 groups (10 mice per group): (1) a blank control group (no exposure to UV radiation), (2) a UVB/no lens group (mice exposed to UVB rays, but without lens protection), (3) a UVB/UV400 group (mice exposed to UVB rays and protected using the CR-39™ spectacle lens [UV400 coating]), and (4) a UVB/photochromic group (mice exposed to UVB rays and protected using the CR-39™ spectacle lens [photochromic coating]). We investigated UVB-induced changes in visual acuity and in corneal smoothness, opacity, and lissamine green staining. We also evaluated the correlation between visual acuity decline and changes to the corneal surface parameters. Tissue sections were prepared and stained immunohistochemically to evaluate the structural integrity of the cornea and conjunctiva. In blank controls, the cornea remained undamaged, whereas in UVB-exposed mice, the corneal surface was disrupted; this disruption significantly correlated with a concomitant decline in visual acuity. Both the UVB/UV400 and UVB/photochromic groups had sharper visual acuity and a healthier corneal surface than the UVB/no lens group. Eyes in both protected groups also showed better corneal and conjunctival structural integrity than unprotected eyes. Furthermore, there were fewer apoptotic cells and less polymorphonuclear leukocyte infiltration in corneas protected by the spectacle lenses. The model established herein reliably determines the protective effect of UV-blocking ophthalmic biomaterials, because the in vivo protection against UV-induced ocular damage and visual acuity decline was easily defined.

Ultraviolet-B radiation and the immune response of rainbow trout: Chapter 18

USGS Publications Warehouse

Fabacher, David L.; Little, Edward E.; Jones, S.B.; DeFabo, E.C.; Webber, L.J.; Stolen, Joanne S.; Fletcher, Thelma C.

1994-01-01

As part of a larger study on global climate change and ozone depletion we are investigating the effects of ultraviolet-B (UVB) radiation on fishes. We conducted a number of experiments to explore the possible effects of UVB radiation on the immune response of juvenile rainbow trout Oncorhynchus mykiss. In one study, the fish developed sunburn and fungal infection on the dorsal skin after exposure to levels of UVB that simulated ambient solar UVB levels observed at mid-latitudes. In a separate study, UVB-exposed rainbow trout with surgically administered dorsal lesions developed fungal infection on the lesions and surrounding skin. Many of these fish subsequently died within a 9 day exposure period. Fish with surgical lesions, but not exposed to UVB radiation, did not develop fungal infection and did not die. In mammals, UVB-induced immunosuppression is thought to occur through the isomerization of urocanic acid or the formation of DNA pyrimidine dimers, or through some interaction between the two. We found a substance that appeared, upon HPLC detection, to be trans-urocanic acid in the skin of UVB-exposed and unexposed rainbow trout. Neurotransmitter stimulation of adrenoceptors may be involved in changes in pigmentation observed in UVB-exposed fishes. We measured adrenoceptors in skin membranes from rainbow trout exposed to UVB and found a decrease in cz2-adrenoceptors compared with fish not exposed to UVB. Results of our study indicate that prolonged exposure of juvenile rainbow trout to mid-latitude levels of solar UVB may play an important role in the initiation of certain disease outbreaks and may decrease survival of fish that have lesions on the dorsal skin.

TNF-R1 and FADD mediate UVB-Induced activation of K+ channels in corneal epithelial cells

PubMed Central

Boersma, Peter M.; Haarsma, Loren D.; Schotanus, Mark P.; Ubels, John L.

2017-01-01

The goal of this study was to elucidate the role of Fas, TNF-R1, FADD and cytochrome c in UVB-induced K+ channel activation, an early step in UVB-induced apoptosis, in human corneal limbal epithelial (HCLE) cells. HCLE cells were treated with Fas, TNF-R1 or FADD siRNA and exposed to 80 or 150 mJ/cm2 UVB. K+ channel activation and loss of intracellular K+ were measured using whole-cell patch-clamp recording and ion chromatography, respectively. Cytochrome c was measured with an ELISA kit. Cells in which Fas was knocked down exhibited identical UVB-induced K+ channel activation and loss of intracellular K+ to control cells. Cells in which TNF-R1 or FADD were knocked down demonstrated reduced K+ channel activation and decreased loss of intracellular K+ following UVB, relative to control cells. Application of TNF-α, the natural ligand of TNF-R1, to HCLE cells induced K+ channel activation and loss of intracellular K+. Cytochrome c was translocated to the cytosol by 2 h after exposure to 150 mJ/cm2 UVB. However, there was no release by 10 min post-UVB. The data suggest that UVB activates TNF-R1, which in turn may activate K+ channels via FADD. This conclusion is supported by the observation that TNF-α also causes loss of intracellular K+. This signaling pathway appears to be integral to UVB-induced K+ efflux, since knockdown of TNF-R1 or FADD inhibits the UVB-induced K+ efflux. The lack of rapid cytochrome c translocation indicates cytochrome c does not play a role in UVB-induced K+ channel activation. PMID:27818316

UV-B radiation-induced oxidative stress and p38 signaling pathway involvement in the benthic copepod Tigriopus japonicus.

PubMed

Kim, Bo-Mi; Rhee, Jae-Sung; Lee, Kyun-Woo; Kim, Min-Jung; Shin, Kyung-Hoon; Lee, Su-Jae; Lee, Young-Mi; Lee, Jae-Seong

2015-01-01

Ultraviolet B (UV-B) radiation presents an environmental hazard to aquatic organisms. To understand the molecular responses of the intertidal copepod Tigriopus japonicus to UV-B radiation, we measured the acute toxicity response to 96 h of UV-B radiation, and we also assessed the intracellular reactive oxygen species (ROS) levels, glutathione (GSH) content, and antioxidant enzyme (GST, GR, GPx, and SOD) activities after 24 h of exposure to UV-B with LD50 and half LD50 values. Also, expression patterns of p53 and hsp gene families with phosphorylation of p38 MAPK were investigated in UV-B-exposed copepods. We found that the ROS level, GSH content, and antioxidant enzyme activity levels were increased with the transcriptional upregulation of antioxidant-related genes, indicating that UV-B induces oxidative stress by generating ROS and stimulating antioxidant enzymatic activity as a defense mechanism. Additionally, we found that p53 expression was significantly increased after UV-B irradiation due to increases in the phosphorylation of the stress-responsive p38 MAPK, indicating that UV-B may be responsible for inducing DNA damage in T. japonicus. Of the hsp family genes, transcriptional levels of hsp20, hsp20.7, hsp70, and hsp90 were elevated in response to a low dose of UV-B radiation (9 kJ m(-2)), suggesting that these hsp genes may be involved in cellular protection against UV-B radiation. In this paper, we performed a pathway-oriented mechanistic analysis in response to UV-B radiation, and this analysis provides a better understanding of the effects of UV-B in the intertidal benthic copepod T. japonicus. Copyright © 2014 Elsevier Inc. All rights reserved.

Antioxidant capacity of flavonoid in soybean seedlings under the joint actions of rare earth element La(III) and ultraviolet-B stress.

PubMed

Peng, Qi; Zhou, Qing

2009-01-01

The dynamic state of antioxidant capacity of flavonoid was investigated for a further demonstration of alleviating the damage of the ultraviolet (UV)-B radiation in the La-treated soybean seedlings under UV-B stress. Using hydroponics culture, the effects of lanthanum on the contents of flavonoid and its ability of antioxidant under elevated ultraviolet-B radiation (280-320 nm) was studied. The results showed flavonoid content in soybean seedlings with UV-B treatment during the stress and convalescent period was increased initially and then decreased, compared with control. Membrane permeability and MDA contents increase at first (first to fifth day) and then decrease (6th-11th day). A similar change of flavonoid content and clearance of flavonoid scavenging O2- and *OH in soybean seedlings occurred. Flavonoid content and ability of flavonoid scavenging O2- and *OH in soybean seedlings with La(III) + UV-B treatment were higher than those of UV-B treatment. Meanwhile, membrane permeability and MDA contents in soybean seedlings were lower than those of UV-B treatment. Compared with control, phenylalanine content in soybean seedlings with UV-B treatment is depressed, phenylalanine content in soybean seedlings with La(III) treatment was enhanced. However, phenylalanine content in La(III) + UV-B treatment is not decreased but slightly increased, compared with UV-B treatment. It suggested that the regulative effect of La(III) of the optimum concentration on flavonoid improved the metabolism of ROS, diminished the concentration of MDA and maintained normal plasma membrane permeability, and that its protective effect against low UV-B radiation is superior to that of high UV-B radiation. The defensive effect of La(III) on soybean seedlings under UV-B stress is carried out on the layer of defense system.

UV-B-Responsive Association of the Arabidopsis bZIP Transcription Factor ELONGATED HYPOCOTYL5 with Target Genes, Including Its Own Promoter[W][OPEN

PubMed Central

Binkert, Melanie; Kozma-Bognár, László; Terecskei, Kata; De Veylder, Lieven; Nagy, Ferenc; Ulm, Roman

2014-01-01

In plants subjected to UV-B radiation, responses are activated that minimize damage caused by UV-B. The bZIP transcription factor ELONGATED HYPOCOTYL5 (HY5) acts downstream of the UV-B photoreceptor UV RESISTANCE LOCUS8 (UVR8) and promotes UV-B-induced photomorphogenesis and acclimation. Expression of HY5 is induced by UV-B; however, the transcription factor(s) that regulate HY5 transcription in response to UV-B and the impact of UV-B on the association of HY5 with its target promoters are currently unclear. Here, we show that HY5 binding to the promoters of UV-B-responsive genes is enhanced by UV-B in a UVR8-dependent manner in Arabidopsis thaliana. In agreement, overexpression of REPRESSOR OF UV-B PHOTOMORPHOGENESIS2, a negative regulator of UVR8 function, blocks UV-B-responsive HY5 enrichment at target promoters. Moreover, we have identified a T/G-box in the HY5 promoter that is required for its UV-B responsiveness. We show that HY5 and its homolog HYH bind to the T/GHY5-box cis-acting element and that they act redundantly in the induction of HY5 expression upon UV-B exposure. Therefore, HY5 is enriched at target promoters in response to UV-B in a UVR8 photoreceptor-dependent manner, and HY5 and HYH interact directly with a T/G-box cis-acting element of the HY5 promoter, mediating the transcriptional activation of HY5 in response to UV-B. PMID:25351492

Rapid transcriptome responses of maize (Zea mays) to UV-B in irradiated and shielded tissues

PubMed Central

Casati, Paula; Walbot, Virginia

2004-01-01

Background Depletion of stratospheric ozone has raised terrestrial levels of ultraviolet-B radiation (UV-B), an environmental change linked to an increased risk of skin cancer and with potentially deleterious consequences for plants. To better understand the processes of UV-B acclimation that result in altered plant morphology and physiology, we investigated gene expression in different organs of maize at several UV-B fluence rates and exposure times. Results Microarray hybridization was used to assess UV-B responses in directly exposed maize organs and organs shielded by a plastic that absorbs UV-B. After 8 hours of high UV-B, the abundance of 347 transcripts was altered: 285 were increased significantly in at least one organ and 80 were downregulated. More transcript changes occurred in directly exposed than in shielded organs, and the levels of more transcripts were changed in adult compared to seedling tissues. The time course of transcript abundance changes indicated that the response kinetics to UV-B is very rapid, as some transcript levels were altered within 1 hour of exposure. Conclusions Most of the UV-B regulated genes are organ-specific. Because shielded tissues, including roots, immature ears, and leaves, displayed altered transcriptome profiles after exposure of the plant to UV-B, some signal(s) must be transmitted from irradiated to shielded tissues. These results indicate that there are integrated responses to UV-B radiation above normal levels. As the same total UV-B irradiation dose applied at three intensities elicited different transcript profiles, the transcriptome changes exhibit threshold effects rather than a reciprocal dose-effect response. Transcriptome profiling highlights possible signaling pathways and molecules for future research. PMID:15003119

Association of UV radiation with multiple sclerosis prevalence and sex ratio in France

PubMed Central

Orton, S.-M.; Wald, L.; Confavreux, C.; Vukusic, S.; Krohn, J.P.; Ramagopalan, S.V.; Herrera, B.M.; Sadovnick, A.D.

2011-01-01

Background: French farmers and their families constitute an informative population to study multiple sclerosis (MS) prevalence and related epidemiology. We carried out an ecological study to evaluate the association of MS prevalence and ultraviolet (UV) radiation, a candidate climatologic risk factor. Methods: Mean annual and winter (December–March) UVB irradiation values were systematically compared to MS prevalence rates in corresponding regions of France. UVB data were obtained from the solar radiation database (SoDa) service and prevalence rates from previously published data on 2,667 MS cases registered with the national farmer health insurance system, Mutualité Sociale Agricole (MSA). Pearson correlation was used to examine the relationship of annual and winter UVB values with MS prevalence. Male and female prevalence were also analyzed separately. Linear regression was used to test for interaction of annual and winter UVB with sex in predicting MS prevalence. Results: There was a strong association between MS prevalence and annual mean UVB irradiation (r = −0.80, p < 0.001) and average winter UVB (r = −0.87, p < 0.001). Both female (r = −0.76, p < 0.001) and male (r = −0.46, p = 0.032) prevalence rates were correlated with annual UVB. Regression modeling showed that the effect of UVB on prevalence rates differed by sex; the interaction effect was significant for both annual UVB (p = 0.003) and winter UVB (p = 0.002). Conclusions: The findings suggest that regional UVB radiation is predictive of corresponding MS prevalence rates and supports the hypothesis that sunlight exposure influences MS risk. The evidence also supports a potential role for gender-specific effects of UVB exposure. PMID:21282589

Comparing a Cognitive Model and Phototherapy in the Treatment of Seasonal Affective Disorder.

ERIC Educational Resources Information Center

Krantz, Sandra

Seasonal affective disorder (SAD) is characterized by recurrent major depression or bipolar disorder that occurs annually, usually later in fall as the daylight hours decrease, and that alternates with euthymic or hypomanic moods in the spring and summer. Pioneering research by Dr. Norman Rosenthal and associates has found phototherapy to be…

POF-yarn weaves: controlling the light out-coupling of wearable phototherapy devices

PubMed Central

Quandt, Brit M.; Pfister, Marisa S.; Lübben, Jörn F.; Spano, Fabrizio; Rossi, René M.; Bona, Gian-Luca; Boesel, Luciano F.

2017-01-01

Neonatal jaundice (hyperbilirubinaemia) is common in neonates and, often, intensive blue-light phototherapy is required to prevent long-term effects. A photonic textile can overcome three major incubator-related concerns: Insulation of the neonate, human contact, and usage restraints. This paper describes the development of a homogeneous luminous textile from polymer optical fibres to use as a wearable, long-term phototherapy device. The bend out-coupling of light from the POFs was related to the weave production, e.g. weave pattern and yarn densities. Comfort, determined by friction against a skin model and breathability, was investigated additionally. Our textile is the first example of phototherapeutic clothing that is produced sans post-processing allowing for faster commercial production. PMID:29082067

Cyanidin-3-glucoside inhibits UVB-induced oxidative damage and inflammation by regulating MAP kinase and NF-κB signaling pathways in SKH-1 hairless mice skin.

PubMed

Pratheeshkumar, Poyil; Son, Young-Ok; Wang, Xin; Divya, Sasidharan Padmaja; Joseph, Binoy; Hitron, John Andrew; Wang, Lei; Kim, Donghern; Yin, Yuanqin; Roy, Ram Vinod; Lu, Jian; Zhang, Zhuo; Wang, Yitao; Shi, Xianglin

2014-10-01

Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicate that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE2 and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2'-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways. Copyright © 2014 Elsevier Inc. All rights reserved.

Cyanidin-3-Glucoside inhibits UVB-induced oxidative damage and inflammation by regulating MAP kinase and NF-κB signalling pathways in SKH-1 hairless mice skin

PubMed Central

Pratheeshkumar, Poyil; Son, Young-Ok; Wang, Xin; Divya, Sasidharan Padmaja; Joseph, Binoy; Hitron, John Andrew; Wang, Lei; Kim, Donghern; Yin, Yuanqin; Roy, Ram Vinod; Lu, Jian; Zhang, Zhuo; Wang, Yitao; Shi, Xianglin

2015-01-01

Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-Glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicate that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE2 and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2′-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways. PMID:25062774

Blackberry extract inhibits UVB-induced oxidative damage and inflammation through MAP kinases and NF-κB signaling pathways in SKH-1 mice skin.

PubMed

Divya, Sasidharan Padmaja; Wang, Xin; Pratheeshkumar, Poyil; Son, Young-Ok; Roy, Ram Vinod; Kim, Donghern; Dai, Jin; Hitron, John Andrew; Wang, Lei; Asha, Padmaja; Shi, Xianglin; Zhang, Zhuo

2015-04-01

Extensive exposure of solar ultraviolet-B (UVB) radiation to skin induces oxidative stress and inflammation that play a crucial role in the induction of skin cancer. Photochemoprevention with natural products represents a simple but very effective strategy for the management of cutaneous neoplasia. In this study, we investigated whether blackberry extract (BBE) reduces chronic inflammatory responses induced by UVB irradiation in SKH-1 hairless mice skin. Mice were exposed to UVB radiation (100 mJ/cm(2)) on alternate days for 10 weeks, and BBE (10% and 20%) was applied topically a day before UVB exposure. Our results show that BBE suppressed UVB-induced hyperplasia and reduced infiltration of inflammatory cells in the SKH-1 hairless mice skin. BBE treatment reduced glutathione (GSH) depletion, lipid peroxidation (LPO), and myeloperoxidase (MPO) in mouse skin by chronic UVB exposure. BBE significantly decreased the level of pro-inflammatory cytokines IL-6 and TNF-α in UVB-exposed skin. Likewise, UVB-induced inflammatory responses were diminished by BBE as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, BBE also reduced inflammatory mediators such as cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and inducible nitric oxide synthase (iNOS) levels in UVB-exposed skin. Treatment with BBE inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mouse skin. Immunohistochemistry analysis revealed that topical application of BBE inhibited the expression of 8-oxo-7, 8-dihydro-2'-deoxyguanosine (8-oxodG), cyclobutane pyrimidine dimers (CPD), proliferating cell nuclear antigen (PCNA), and cyclin D1 in UVB-exposed skin. Collectively, these data indicate that BBE protects from UVB-induced oxidative damage and inflammation by modulating MAP kinase and NF-κB signaling pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

The Polyphenol Chlorogenic Acid Attenuates UVB-mediated Oxidative Stress in Human HaCaT Keratinocytes

PubMed Central

Cha, Ji Won; Piao, Mei Jing; Kim, Ki Cheon; Yao, Cheng Wen; Zheng, Jian; Kim, Seong Min; Hyun, Chang Lim; Ahn, Yong Seok; Hyun, Jin Won

2014-01-01

We investigated the protective effects of chlorogenic acid (CGA), a polyphenol compound, on oxidative damage induced by UVB exposure on human HaCaT cells. In a cell-free system, CGA scavenged 1,1-diphenyl-2-picrylhydrazyl radicals, superoxide anions, hydroxyl radicals, and intracellular reactive oxygen species (ROS) generated by hydrogen peroxide and ultraviolet B (UVB). Furthermore, CGA absorbed electromagnetic radiation in the UVB range (280–320 nm). UVB exposure resulted in damage to cellular DNA, as demonstrated in a comet assay; pre-treatment of cells with CGA prior to UVB irradiation prevented DNA damage and increased cell viability. Furthermore, CGA pre-treatment prevented or ameliorated apoptosis-related changes in UVB-exposed cells, including the formation of apoptotic bodies, disruption of mitochondrial membrane potential, and alterations in the levels of the apoptosis-related proteins Bcl-2, Bax, and caspase-3. Our findings suggest that CGA protects cells from oxidative stress induced by UVB radiation. PMID:24753819

Pollen sensitivity to ultraviolet-B (UV-B) suggests floral structure evolution in alpine plants.

PubMed

Zhang, Chan; Yang, Yong-Ping; Duan, Yuan-Wen

2014-03-31

Various biotic and abiotic factors are known to exert selection pressures on floral traits, but the influence of ultraviolet-B (UV-B) light on the evolution of flower structure remains relatively unexplored. We have examined the effectiveness of flower structure in blocking radiation and the effects of UV-B on pollen viability in 42 species of alpine plants in the Hengduan Mountains, China. Floral forms were categorized as either protecting or exposing pollen grains to UV-B. The floral materials of plants with exposed and protected pollen grains were able to block UV-B at similar levels. Exposure to UV-B radiation in vitro resulted in a significantly greater loss of viability in pollen from plant species with protective floral structures. The pronounced sensitivity of protected pollen to UV-B radiation was associated with the type of flower structure. These findings demonstrate that UV-B plays an important role in the evolution of protective floral forms in alpine plants.

The dominant allele Aft induces a shift from flavonol to anthocyanin production in response to UV-B radiation in tomato fruit.

PubMed

Catola, Stefano; Castagna, Antonella; Santin, Marco; Calvenzani, Valentina; Petroni, Katia; Mazzucato, Andrea; Ranieri, Annamaria

2017-08-01

The introgression of the A ft allele into domesticated tomato induced a shift from flavonol to anthocyanin production in response to UV-B radiation, while the hp - 1 allele negatively influenced the response of flavonoid biosynthesis to UV-B. Introgression of the dominant allele Anthocyanin fruit (Aft) from Solanum chilense induces anthocyanin accumulation in the peel of tomato (Solanum lycopersicum L.) fruit. UV-B radiation can influence plant secondary metabolism regulating the expression of several genes, among which those involved in flavonoid biosynthesis. Here, we investigated whether post-harvest UV-B treatment could up-regulate flavonoid production in tomato fruits and whether the Aft allele could affect flavonoid biosynthesis under UV-B radiation. Mature green fruits of an anthocyanin-rich tomato mutant line (SA206) and of its wild-type reference, cv. Roma, were daily subjected to post-harvest UV-B treatment until full ripening. Up-regulation of CHS and CHI transcription by UV-B treatment induced flavonoid accumulation in the peel of cv. Roma. Conversely, UV-B decreased the total flavonoid content and CHS transcript levels in the SA206 peel. SA206 being a double mutant containing also hp-1 allele, we investigated also the behavior of hp-1 fruit. The decreased peel flavonoid accumulation and gene transcription in response to UV-B suggest that hp-1 allele is involved in the marked down-regulation of the flavonoid biosynthesis observed in SA206 fruit. Interestingly, in SA206, UV-B radiation promoted the synthesis of delphinidin, petunidin, and malvidin by increasing F3'5'H and DFR transcription, but it decreased rutin production, suggesting a switch from flavonols to anthocyanins. Finally, although UV-B radiation does not reach the inner fruit tissues, it down-regulated flavonoid biosynthesis in the flesh of both genotypes. This study provides, for the first time, evidence that the presence of the functional Aft allele, under UV-B radiation, redirects flavonoid synthesis towards anthocyanin production and suggests that the hp-1 allele negatively influences the response of flavonoid biosynthesis to UV-B.

DHU1 negatively regulates UV-B signaling via its direct interaction with COP1 and RUP1.

PubMed

Kim, Sang-Hoon; Kim, Hani; Chung, Sunglan; Lee, Jae-Hoon

2017-09-16

Although DWD HYPERSENSITIVE TO UV-B 1 (DHU1) is reported to be a negative regulator in UV-B mediated cellular responses, its detailed role in UV-B signaling is still elusive. To further understand the action mechanism of DHU1 in UV-B response, physical and genetic interactions of DHU1 with various UV-B signaling components were investigated. Yeast two hybrid assay results suggested that DHU1 directly interacts with COP1 and RUP1, implying a functional connection with both COP1 and RUP1. In spite of the physical association between DHU1 and COP1, loss of DHU1 did not affect protein stability of COP1. Epistatic analysis showed that the functional loss of both DHU1 and UVR8 leads to alleviation of UV-B hypersensitivity displayed in dhu1-1. Moreover, phenotypic studies with dhu1-1 cop1-6 and dhu1-1 hy5-215 revealed that COP1 and HY5 are epistatic to DHU1, indicating that UV-B hypersensitivity of dhu1-1 requires both COP1 and HY5. In the case of dhu1-1 rup1-1, UV-B responsiveness was similar to that of both dhu1-1 and rup1-1, implying that DHU1 and RUP1 are required for each other's function. Collectively, these results show that the role of DHU1 as a negative regulator in UV-B response may be derived from its direct interaction with COP1 by sequestering COP1 from the active UVR8-COP1 complex, resulting in a decrease in the COP1 population that positively participates in UV-B signaling together with UVR8. Furthermore, this inhibitory role of DHU1 in UV-B signaling is likely to be functionally connected to RUP1. This study will serve as a platform to further understand more detailed action mechanism of DHU1 in UV-B response and DHU1-mediated core UV-B signaling in Arabidopsis. Copyright © 2017 Elsevier Inc. All rights reserved.

UV-B light contributes directly to the synthesis of chiloglottone floral volatiles

PubMed Central

Amarasinghe, Ranamalie; Poldy, Jacqueline; Matsuba, Yuki; Barrow, Russell A.; Hemmi, Jan M.; Pichersky, Eran; Peakall, Rod

2015-01-01

Background and Aims Australian sexually deceptive Chiloglottis orchids attract their specific male wasp pollinators by means of 2,5-dialkylcyclohexane-1,3-diones or ‘chiloglottones’, representing a newly discovered class of volatiles with unique structures. This study investigated the hypothesis that UV-B light at low intensities is directly required for chiloglottone biosynthesis in Chiloglottis trapeziformis. Methods Chiloglottone production occurs only in specific tissue (the callus) of the labellum. Cut buds and flowers, and whole plants with buds and flowers, sourced from the field, were kept in a growth chamber and interactions between growth stage of the flowers and duration and intensity of UV-B exposure on chiloglottone production were studied. The effects of the protein synthesis inhibitor cycloheximide were also examined. Key Results Chiloglottone was not present in buds, but was detected in buds that were manually opened and then exposed to sunlight, or artificial UV-B light for ≥5 min. Spectrophotometry revealed that the sepals and petals blocked UV-B light from reaching the labellum inside the bud. Rates of chiloglottone production increased with developmental stage, increasing exposure time and increasing UV-B irradiance intensity. Cycloheximide did not inhibit the initial production of chiloglottone within 5 min of UV-B exposure. However, inhibition of chiloglottone production by cycloheximide occurred over 2 h of UV-B exposure, indicating a requirement for de novo protein synthesis to sustain chiloglottone production under UV-B. Conclusions The sepals and petals of Chiloglottis orchids strongly block UV-B wavelengths of light, preventing chiloglottone production inside the bud. While initiation of chiloglottone biosynthesis requires only UV-B light, sustained chiloglottone biosynthesis requires both UV-B and de novo protein biosynthesis. The internal amounts of chiloglottone in a flower reflect the interplay between developmental stage, duration and intensity of UV-B exposure, de novo protein synthesis, and feedback loops linked to the starting amount of chiloglottone. It is concluded that UV-B light contributes directly to chiloglottone biosynthesis. These findings suggest an entirely new and unexpected biochemical reaction that might also occur in taxa other than these orchids. PMID:25649114

Inhibition of ultraviolet light-induced oxidative events in the skin and internal organs of hairless mice by isoflavone genistein.

PubMed

Wei, Huachen; Zhang, Xueshu; Wang, Yan; Lebwohl, Mark

2002-11-08

We have previously demonstrated that soybean isoflavone genistein inhibits ultraviolet-B (UVB)-induced skin tumorigenesis in hairless mice. In the present study, we further investigated the possible mechanism(s) of action whereby genistein inhibits photocarcinogenesis with focuses on UVB-induced oxidative events, including hydrogen peroxide (H(2)O(2)) production, lipid peroxidation (as represented by malondialdehyde, MDA), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) formation in vivo. We demonstrated that subacute exposure to UVB substantially increased the level of H(2)O(2), lipid peroxides, and 8-OHdG in skin of hairless mice. In addition, chronic exposure to low-dose UVB (0.9-1.2 kJ/m(2) for 20 weeks) substantially increased the levels of 8-OHdG not only in the epidermis, but also in the internal organs such as liver, brain, and spleen of mice with exception of kidney. However, genistein did not affect the level of UVB-induced pyrimidine dimmers in the same UVB exposed mouse skin, indicating selective inhibition of oxidative DNA damage by genistein. Induction of H(2)O(2) was independent of UVB fluences whereas the levels of MDA and 8-OHdG were induced in an UVB fluence-dependent manner. The results suggest that H(2)O(2) be generated as an acute cutaneous response to UVB irradiation, while MDA and 8-OHdG are accumulated with increasing UVB exposure and more closely related to chronic effects of UVB radiation. Pre-treatment of animals with 10 micromol of genistein 1 h prior to UVB exposure significantly inhibited UVB-induced H(2)O(2) and MDA in skin and 8-OHdG in epidermis as well as internal organs. Suppression of 8-OHdG formation by genistein has been corroborated in purified DNA irradiated with UVA and B. In summary, our results suggest that UVB irradiation elicit a series of oxidative events, which can be substantially inhibited by isoflavonoid genistein through either direct quenching of reactive oxygen species or indirect antiinflammatory effects. Thus, the antioxidative properties of genistein may explain for the mechanisms of anti-photocarcinogenic action of genistein.

Simulation study of natural UV-B radiation on Catla catla and its impact on physiology, oxidative stress, Hsp 70 and DNA fragmentation.

PubMed

Singh, Moirangthem Kameshwor; Sharma, Jai Gopal; Chakrabarti, Rina

2015-08-01

UV-B radiation is a potential stressor to the aquacultural species. Catla catla, catla larvae (1.08±0.065g) were exposed to different doses of UV-B radiation, 0 (control), 504, 1008, 1512 and 2016mJ/cm(2) at a mean radiant energy of 80μW/cm(2) for 21days. The dose of UV-B radiation was selected on the basis of the field study conducted in Lake Naini, Delhi, India (Latitude: 28°41'26″N and Longitude: 77°12″37″E). Significantly (P<0.05) lower survival, average weight and specific growth rate were found in UV-B irradiated larvae compared to the control one. Food conversion ratio was 1.5-4-fold higher in UV-B treated larvae compared to the control one. The carbonyl protein (CP), thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD) levels were significantly (P <0.05) higher in UV-B irradiated larvae compared to the control group. Among the treated larvae, CP and SOD were significantly (P <0.05) higher in larvae exposed at 1512mJ/cm(2) UV-B. A correlation was found between the CP and SOD (R(2)=0.834). Highest TBARS level was found in 2016mJ/cm(2) UV-B exposed catla. Nitric oxide synthase level was significantly (P <0.05) lower in UV-B exposed larvae compared to the control one. A 3-fold increased Hsp 70 level was recorded in UV-B irradiated catla compared to the control larvae. Comet assay analysis indicated that UV-B irradiation enhanced DNA fragmentation. Tail extent moment and the olive tail moment were significantly (P <0.05) higher in 2016mJ/cm(2) UV-B exposed catla compared to others. The tail length was significantly (P <0.05) higher in 1512 and 2016mJ/cm(2) UV-B exposed larvae compared to the other doses. The present study suggests that the catla is a useful species for the biomonitoring of stress in the aquatic environment. Copyright © 2015 Elsevier B.V. All rights reserved.

Soybean resistance to stink bugs (Nezara viridula and Piezodorus guildinii) increases with exposure to solar UV-B radiation and correlates with isoflavonoid content in pods under field conditions.

PubMed

Zavala, Jorge A; Mazza, Carlos A; Dillon, Francisco M; Chludil, Hugo D; Ballaré, Carlos L

2015-05-01

Solar UV-B radiation (280-315 nm) has a significant influence on trophic relationships in natural and managed ecosystems, affecting plant-insect interactions. We explored the effects of ambient UV-B radiation on the levels of herbivory by stink bugs (Nezara viridula and Piezodorus guildinii) in field-grown soybean crops. The experiments included two levels of UV-B radiation (ambient and attenuated UV-B) and four soybean cultivars known to differ in their content of soluble leaf phenolics. Ambient UV-B radiation increased the accumulation of the isoflavonoids daidzin and genistin in the pods of all cultivars. Soybean crops grown under attenuated UV-B had higher numbers of unfilled pods and damaged seeds than crops grown under ambient UV-B radiation. Binary choice experiments with soybean branches demonstrated that stink bugs preferred branches of the attenuated UV-B treatment. We found a positive correlation between percentage of undamaged seeds and the contents of daidzin and genistin in pods. Our results suggest that constitutive and UV-B-induced isoflavonoids increase plant resistance to stink bugs under field conditions. © 2014 John Wiley & Sons Ltd.

An ethanol extract derived from Bonnemaisonia hamifera scavenges ultraviolet B (UVB) radiation-induced reactive oxygen species and attenuates UVB-induced cell damage in human keratinocytes.

PubMed

Piao, Mei Jing; Hyun, Yu Jae; Cho, Suk Ju; Kang, Hee Kyoung; Yoo, Eun Sook; Koh, Young Sang; Lee, Nam Ho; Ko, Mi Hee; Hyun, Jin Won

2012-12-14

The present study investigated the photoprotective properties of an ethanol extract derived from the red alga Bonnemaisonia hamifera against ultraviolet B (UVB)-induced cell damage in human HaCaT keratinocytes. The Bonnemaisonia hamifera ethanol extract (BHE) scavenged the superoxide anion generated by the xanthine/xanthine oxidase system and the hydroxyl radical generated by the Fenton reaction (FeSO₄ + H₂O₂), both of which were detected by using electron spin resonance spectrometry. In addition, BHE exhibited scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl radical and intracellular reactive oxygen species (ROS) that were induced by either hydrogen peroxide or UVB radiation. BHE reduced UVB-induced apoptosis, as shown by decreased apoptotic body formation and DNA fragmentation. BHE also attenuated DNA damage and the elevated levels of 8-isoprostane and protein carbonyls resulting from UVB-mediated oxidative stress. Furthermore, BHE absorbed electromagnetic radiation in the UVB range (280-320 nm). These results suggest that BHE protects human HaCaT keratinocytes against UVB-induced oxidative damage by scavenging ROS and absorbing UVB photons, thereby reducing injury to cellular components.

Response of Two Legumes to Two Ultraviolet-B Radiation Regimes

NASA Technical Reports Server (NTRS)

Levy, Daniel L.; Skiles, J. W.

2000-01-01

Depletion of the stratospheric ozone layer has been directly linked to increased levels of UV radiation at the earth's surface. The purpose of this study was to evaluate the responses of soybean (Glycine max) and alfalfa (Medicago sativa) to increased UV-B radiation (280-320 nm). Soybean and alfalfa were grown successively in a growth chamber that provided UV-B intensities 45% above nominal summer field levels. Mylar-D (UVB opaque) and mono-acetate (UV-B transparent) films were used to establish the two UV-B treatments. Soybean grown under increased UV showed 21% smaller internodal lengths and higher concentrations of UV-B absorbing pigments (i.e. flavonoids) compared to plants grown under no UV. Significant results for alfalfa included 22% greater leaf flavonoid concentration under increased UV, 14% greater leaf chlorophyll concentration under no UV, and 32% greater above-ground biomass with no UV. These leguminous species possess mechanisms that protect against UV-B damage as indicated by increases in foliar concentrations of UV-B absorbing compounds. Alfalfa appears to be more sensitive to UV-B damage than soybean. Remote sensing of chlorophyll fluorescence may offer a means of monitoring UV-induced plant stress and damage.

Protective effect of Schizandrin B against damage of UVB irradiated skin cells depend on inhibition of inflammatory pathways.

PubMed

Gao, Chenguang; Chen, Hong; Niu, Cong; Hu, Jie; Cao, Bo

2017-01-02

Schizandrin B is extracted from Schisandra chinensis (Turcz.) Baill. This study evaluated the photoprotective effect of Schizandrin B on oxidative stress injury of the skin caused by UVB-irradiation and the molecular mechanism of the photoprotective effect of Schizandrin B, and we firstly found that Schizandrin B could block Cox-2, IL-6 and IL-18 signal pathway to protect damage of skin cells given by UVB-irradiation. In the research, we found that Schizandrin B can attenuate the UVB-induced toxicity on keratinocytes and dermal fibroblasts in human body, and can outstandingly eliminated intracellular ROS produced by UVB-irradiation. These results demonstrate that Schizandrin B can regulate the function of decreasing intracellular SOD's activity and increasing the expression level of MDA in HaCaT cells result from the guidance of UVB, and it markedly reduced the production of inflammatory factors such as Cox-2, IL-6 or IL-18, decreased the expression level of MMP-1, and interdicted degradation process of collagens in UVB-radiated cells. Therefore, skin keratinocytes can be effectively protected from UVB-radiated damage by Schizandrin B, and UVB-irradiation caused inflammatory responses can be inhibited by attenuating process of ROS generating.

ESTIMATION OF UV-B EXPOSURE IN AMPHIBIAN AQUATIC ENVIRONMENTS

EPA Science Inventory

Estimation of ultraviolet radiation B (UV-B; 280 to 320 nm wavelenghts) dose is essential for determining whether UV-B contributes to amphibian population declines and malformations. UV-B dose in wetlands is effected by location, time of day and year, atmospheric levels of ozone,...

The Canadian Ozone Watch and UV-B advisory programs

NASA Technical Reports Server (NTRS)

Kerr, J. B.; Mcelroy, C. T.; Tarasick, D. W.; Wardle, D. I.

1994-01-01

The Ozone Watch, initiated in March, 1992, is a weekly bulletin describing the state of the ozone layer over Canada. The UV-B advisory program, which started in May, 1992, produces daily forecasts of clear-sky UV-B radiation. The forecast procedures use daily ozone measurements from the eight-station monitoring network, the output from the Canadian operational forecast model and a UV-B algorithm based on three years of spectral UV-B measurements with the Brewer spectrophotometer.

Changes in growth, leaf anatomy and pigment concentrations in pea under modulated UV-B field treatments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Day, T.A.; Howells, B.W.; Ruhland, C.T.

1995-06-01

In growth-chamber and greenhouse studies, garden pea is typically quite sensitive to enhanced UV-B radiation (280-320 nm). We assessed whether growth of pea was reduced under more ecologically relevant UV-B enhancements by employing modulated field lampbanks simulating 0, 16 or 24% ozone depletion. We also examined if these UV-B treatments altered leaf anatomy and concentrations of chlorophyll and UV-B-absorbing compounds, and whether this was dependent on leaf age. We used Pisum sativum mutant Argenteum which has an easily detachable epidermis that allowed us to compare concentrations in epidermal and mesophyll tissues. There were no significant UV-B effects on whole-plant growth.more » Of the 15 leaf-level parameters we examined, UV-B had a strong effect on only two parameters: the ratio of UV-B-absorbing compounds to chlorophyll (which increased with UV-B dose), and stomatal density of the adaxial surface (which decreased with UV-B dose). Chlorophyll concentrations tended to decrease, while the proportion of UV-B-absorbing compounds in the adaxial epidermis tended to increase with UV-B dose (p = 0.11 for both). In contrast to UV-B effects, we found strong leaf-age effects on nearly all parameters except the ratio of UV-B-absorbing compounds to chlorophyll, which remained relatively constant with leaf age.« less

Quercitrin protects skin from UVB-induced oxidative damage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yin, Yuanqin; Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY; Li, Wenqi

Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidativemore » damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin. - Highlights: • Oxidative stress plays a key role in UV-induced cell and tissue injuries. • Quercitrin decreases ROS generation and restores antioxidants irradiated by UVB. • Quercitrin reduces UVB-irradiated oxidative DNA damage, apoptosis, and inflammation. • Quercitrin functions as an antioxidant against UVB-induced skin injuries.« less

Characterization of the adaptive response of grapevine (cv. Tempranillo) to UV-B radiation under water deficit conditions.

PubMed

Martínez-Lüscher, J; Morales, F; Delrot, S; Sánchez-Díaz, M; Gomès, E; Aguirreolea, J; Pascual, I

2015-03-01

This work aims to characterize the physiological response of grapevine (Vitis vinifera L.) cv. Tempranillo to UV-B radiation under water deficit conditions. Grapevine fruit-bearing cuttings were exposed to three levels of supplemental biologically effective UV-B radiation (0, 5.98 and 9.66kJm(-2)day(-1)) and two water regimes (well watered and water deficit), in a factorial design, from fruit-set to maturity under glasshouse-controlled conditions. UV-B induced a transient decrease in net photosynthesis (Anet), actual and maximum potential efficiency of photosystem II, particularly on well watered plants. Methanol extractable UV-B absorbing compounds (MEUVAC) concentration and superoxide dismutase activity increased with UV-B. Water deficit effected decrease in Anet and stomatal conductance, and did not change non-photochemical quenching and the de-epoxidation state of xanthophylls, dark respiration and photorespiration being alternative ways to dissipate the excess of energy. Little interactive effects between UV-B and drought were detected on photosynthesis performance, where the impact of UV-B was overshadowed by the effects of water deficit. Grape berry ripening was strongly delayed when UV-B and water deficit were applied in combination. In summary, deficit irrigation did not modify the adaptive response of grapevine to UV-B, through the accumulation of MEUVAC. However, combined treatments caused additive effects on berry ripening. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Distinct physiological and metabolic reprogramming by highbush blueberry (Vaccinium corymbosum) cultivars revealed during long-term UV-B radiation.

PubMed

Luengo Escobar, Ana; Alberdi, Miren; Acevedo, Patricio; Machado, Mariana; Nunes-Nesi, Adriano; Inostroza-Blancheteau, Claudio; Reyes-Díaz, Marjorie

2017-05-01

Despite the Montreal protocol and the eventual recovery of the ozone layer over Antarctica, there are still concerns about increased levels of ultraviolet-B (UV-B) radiation in the Southern Hemisphere. UV-B induces physiological, biochemical and morphological stress responses in plants, which are species-specific and different even for closely related cultivars. In woody plant species, understanding of long-term mechanisms to cope with UV-B-induced stress is limited. Therefore, a greenhouse UV-B daily course simulation was performed for 21 days with two blueberry cultivars (Legacy and Bluegold) under UV-B BE irradiance doses of 0, 0.07 and 0.19 W m -2 . Morphological changes, photosynthetic performance, antioxidants, lipid peroxidation and metabolic features were evaluated. We found that both cultivars behaved differently under UV-B exposure, with Legacy being a UV-B-resistant cultivar. Interestingly, Legacy used a combined strategy: initially, in the first week of exposure its photoprotective compounds increased, coping with the intake of UV-B radiation (avoidance strategy), and then, increasing its antioxidant capacity. These strategies proved to be UV-B radiation dose dependent. The avoidance strategy is triggered early under high UV-B radiation in Legacy. Moreover, the rapid metabolic reprogramming capacity of this cultivar, in contrast to Bluegold, seems to be the most relevant contribution to its UV-B stress-coping strategy. © 2016 Scandinavian Plant Physiology Society.

Proteomic analysis of UVB-induced protein expression- and redox-dependent changes in skin fibroblasts using lysine- and cysteine-labeling two-dimensional difference gel electrophoresis.

PubMed

Wu, Chieh-Lin; Chou, Hsiu-Chuan; Cheng, Chao-Sheng; Li, Ji-Min; Lin, Szu-Ting; Chen, Yi-Wen; Chan, Hong-Lin

2012-04-03

UVB is the most energetic and DNA-damaging to humans in ultraviolet radiation. Previous research has suggested that exposure to UVB causes skin pathologies because of direct DNA damage and the generation of reactive oxygen species (ROS). However, the detailed molecular mechanisms by which UVB leads to skin cancer have yet to be clarified. In the current study, normal skin fibroblast cells (CCD-966SK) were exposed to various doses of UVB, and the changes in protein expression and thiol reactivity were monitored with lysine- and cysteine-labeling 2D-DIGE and MALDI-TOF mass spectrometry. Our proteomic analysis revealed that 89 identified proteins showed significant changes in protein expression, and 37 in thiol reactivity. Many proteins that are known to be involved in protein folding, redox regulation and nucleotide biosynthesis were up-regulated under UVB irradiation. In contrast, proteins responsible for biosynthesis and protein degradation were down-regulated. In addition, the thiol-reactivity of proteins involving cytoskeleton, metabolism, and signal transduction were altered by UVB. In summary, these UVB-modulated cellular proteins and redox-regulated proteins might play important roles in the early stages of skin cancer formation and photoaging induced by UVB-irradiation. Such proteins might provide a potential target for the rational design of drugs to prevent UVB-induced diseases. Copyright © 2011 Elsevier B.V. All rights reserved.

The protective roles of TiO2 nanoparticles against UV-B toxicity in Daphnia magna.

PubMed

Liu, Jie; Wang, Wen-Xiong

2017-09-01

Aquatic environments are increasingly under environmental stress due to ultraviolet (UV) radiation and potential inputs of nanoparticles with intense application of nanotechnology. In this study, we investigated the interaction between UV-B radiation and titanium nanoparticles (TiO 2 -NPs) in a model freshwater cladoceran Daphnia magna. UV-B toxicity to Daphnia magna was examined when the daphnids were exposed to a range of TiO 2 -NPs concentrations with an initial 5 or 10min of 200μW/cm 2 UV-B radiation. In addition, UV-B toxicity was also examined in the presence of TiO 2 -NPs in the body of daphnids. Our results demonstrated that the daphnid mortality under UV-B radiation decreased significantly in the presence of TiO 2 -NPs both in the water and in the body, indicating that TiO 2 -NPs had some protective effects on D. magna against UV-B. Such protective effect was mainly caused by the blockage of UV-B by TiO 2 -NPs adsorption. UV-B produced reactive oxygen species (ROS) in the water and in the daphnids, which was not sufficient to cause mortality of daphnids over short periods of radiation. Previous studies focused on the effects of TiO 2 -NPs on the toxicity of total UV radiation, and did not attempt to differentiate the potential diverse roles of UV-A and UV-B. Our study indicated that TiO 2 -NPs may conversely protect the UV-B toxicity to daphnids. Copyright © 2017 Elsevier B.V. All rights reserved.

Adverse Effects of UV-B Radiation on Plants Growing at Schirmacher Oasis, East Antarctica.

PubMed

Singh, Jaswant; Singh, Rudra P

2014-01-01

This study aimed to assess the impacts of ultraviolet-B (UV-B) radiation over a 28-day period on the levels of pigments of Umbilicaria aprina and Bryum argenteum growing in field. The depletion of stratospheric ozone is most prominent over Antarctica, which receives more UV-B radiation than most other parts of the planet. Although UV-B radiation adversely affects all flora, Antarctic plants are better equipped to survive the damaging effects of UV-B owing to defenses provided by UV-B absorbing compounds and other screening pigments. The UV-B radiations and daily average ozone values were measured by sun photometer and the photosynthetic pigments were analyzed by the standard spectrophotometric methods of exposed and unexposed selected plants. The daily average atmospheric ozone values were recorded from 5 January to 2 February 2008. The maximum daily average for ozone (310.7 Dobson Units (DU)) was recorded on 10 January 2008. On that day, average UV-B spectral irradiances were 0.016, 0.071, and 0.186 W m(-2) at wavelengths of 305, 312, and 320 nm, respectively. The minimum daily average ozone value (278.6 DU) was recorded on 31 January 2008. On that day, average UV-B spectral irradiances were 0.018, 0.085, and 0.210 W m(-2) at wavelengths of 305, 312, and 320 nm, respectively. Our results concludes that following prolonged UV-B exposure, total chlorophyll levels decreased gradually in both species, whereas levels of UV-B absorbing compounds, phenolics, and carotenoids gradually increased.

Adverse Effects of UV-B Radiation on Plants Growing at Schirmacher Oasis, East Antarctica

PubMed Central

Singh, Jaswant; Singh, Rudra P.

2014-01-01

This study aimed to assess the impacts of ultraviolet-B (UV-B) radiation over a 28-day period on the levels of pigments of Umbilicaria aprina and Bryum argenteum growing in field. The depletion of stratospheric ozone is most prominent over Antarctica, which receives more UV-B radiation than most other parts of the planet. Although UV-B radiation adversely affects all flora, Antarctic plants are better equipped to survive the damaging effects of UV-B owing to defenses provided by UV-B absorbing compounds and other screening pigments. The UV-B radiations and daily average ozone values were measured by sun photometer and the photosynthetic pigments were analyzed by the standard spectrophotometric methods of exposed and unexposed selected plants. The daily average atmospheric ozone values were recorded from 5 January to 2 February 2008. The maximum daily average for ozone (310.7 Dobson Units (DU)) was recorded on 10 January 2008. On that day, average UV-B spectral irradiances were 0.016, 0.071, and 0.186 W m-2 at wavelengths of 305, 312, and 320 nm, respectively. The minimum daily average ozone value (278.6 DU) was recorded on 31 January 2008. On that day, average UV-B spectral irradiances were 0.018, 0.085, and 0.210 W m-2 at wavelengths of 305, 312, and 320 nm, respectively. Our results concludes that following prolonged UV-B exposure, total chlorophyll levels decreased gradually in both species, whereas levels of UV-B absorbing compounds, phenolics, and carotenoids gradually increased. PMID:24748743

[Effect of lanthanum on the flavonoids contents and antioxidant capacity in soybean seedling under ultraviolet-B stress].

PubMed

Peng, Qi; Zhou, Qing

2008-07-01

Dynamic state of antioxidant capacity of flavonoids was investigated for a further demonstration of alleviating the damage of the UV-B radiation in the La-treated soybean seedlings under UV-B stress. Using hydroponics culture, the effects of lanthanum on the contents of flavonoids and its ability of antioxidant under elevated ultraviolet-B radiation (280-320 nm) was studied in this paper. The results showed flavonoids contents in Soybean seedlings during the stress and convalescent period increase firstly and then reduce. Membrane permeability and MDA contents increase firstly (1st-5th day) and then fall (6th to 11th day). A similar change of flavonoids contents and clearance of flavonoids scavenging O2*- and *OH in soybean seedlings occur; the flavonoids contents La(III) + UV-B > UV-B > La(III) > CK, La(III) + T1 > La(III) + T2. Plasma membrane permeability and MAD contents UV-B> La(III) + UV-B > CK > La(III), La(III) + T2 > La(III) + T1. The ability of Scavenging activities of free radical (O2*-, *OH) La(III) + UV-B > UV-B > La(III) > CK. It suggested that the regulative effect of La(III) on flavonoids, improved the metabolism of ROS, diminished the concentration of MDA and maintained normal Plasma membrane permeability, and that its protective effect against low UV-B radiation was superior to that of high UV-B radiation. To conclude, the defensive effect of La(III) on soybean seedlings under UV-B stress was carried out on the layer of defense system.

Egg hatching response to a range of ultraviolet-B (UV-B) radiation doses for four predatory mites and the herbivorous spider mite Tetranychus urticae.

PubMed

Koveos, Dimitrios S; Suzuki, Takeshi; Terzidou, Anastasia; Kokkari, Anastasia; Floros, George; Damos, Petros; Kouloussis, Nikos A

2017-01-01

Egg hatchability of four predatory mites-Phytoseiulus persimilis Athias-Henriot, Iphiseius [Amblyseius] degenerans Berlese, Amblyseius swirskii Athias-Henriot, and Euseius finlandicus Oudemans (Acari: Phytoseiidae)-and the spider mite Tetranychus urticae Koch (Acari: Tetranychidae) was determined under various UV-B doses either in constant darkness (DD) or with simultaneous irradiation using white light. Under UV-B irradiation and DD or simultaneous irradiation with white light, the predator's eggs hatched in significantly lower percentages than in the control non-exposed eggs, which indicates deleterious effects of UV-B on embryonic development. In addition, higher hatchability percentages were observed under UV-B irradiation and DD in eggs of the predatory mites than in eggs of T. urticae. This might be caused by a higher involvement of an antioxidant system, shield effects by pigments or a mere shorter duration of embryonic development in predatory mites than in T. urticae, thus avoiding accumulative effects of UV-B. Although no eggs of T. urticae hatched under UV-B irradiation and DD, variable hatchability percentages were observed under simultaneous irradiation with white light, which suggests the involvement of a photoreactivation system that reduces UV-B damages. Under the same doses with simultaneous irradiation with white light, eggs of T. urticae displayed higher photoreactivation and were more tolerant to UV-B than eggs of the predatory mites. Among predators variation regarding the tolerance to UV-B effects was observed, with eggs of P. persimilis and I. degenerans being more tolerant to UV-B radiation than eggs of A. swirskii and E. finlandicus.

Thallium (Tl) sorption onto illite and smectite: Implications for Tl mobility in the environment

NASA Astrophysics Data System (ADS)

Martin, Loïc A.; Wissocq, Aubéry; Benedetti, M. F.; Latrille, Christelle

2018-06-01

Clay minerals play a relevant role in the transport and fate of trace elements in the environment. Though illite has been referred as an important Thallium (Tl) bearing phase in soils, mechanisms and affinity of thallium for clay minerals remain poorly known. This study investigated the sorption behavior of thallium as Tl(I) onto illite and smectite, two clay minerals occurring mainly in soils and sediments. Different sorption experiments were carried out under various pH conditions and Tl concentrations, in competition with sodium and calcium at a constant ionic strength of 0.01 mol L-1. Our results showed that illite displayed more affinity than smectite for thallium. With illite, the distribution coefficients (Kd in L kg-1) varied between 102.75 ± 0.17 and 104.0 ± 0.17 in Na solutions versus between 102.25 ± 0.17 and 103.0 ± 0.17 in Ca solutions, depending on pH. With smectite, Kd (in L kg-1) ranged between 102.50 ± 0.16 and 103.20 ± 0.16 and between 101.25 ± 0.16 and 101.95 ± 0.16 in Na and Ca solutions, respectively. Sorption behavior was described with the Multi-Site Ion Exchanger model and selectivity coefficients with respect to protons were calculated for the first time. In all cases, independently of clay mineral and background electrolyte, low capacity but highly reactive sites were dominant in thallium uptake, highlighting Tl affinity for those sites. Moreover, the exchangeable and reversible interactions between Tl+ and clays reactive sites suggested that in changing conditions, thallium could be released in solution. The role of clay minerals in thallium environmental cycle is evident and confirmed illite to be a dominant Tl bearing phase, in some environment competing with manganese oxides. Compared to others Tl bearing mineral phases, clays are ranked as follows: MnO2 > illite > smectite ∼ ferrihydrite ≥ Al2O3 ∼ goethite > SiO2. Finally, over the three monovalent cations (Tl, Rb, Cs) Tl is the one less sorbed on illite independently of the background cations.

Effects of Saccharomyces boulardii on neonatal hyperbilirubinemia: a randomized controlled trial.

PubMed

Serce, Ozge; Gursoy, Tugba; Ovali, Fahri; Karatekin, Guner

2015-02-01

Since probiotics modulate intestinal functions and enterohepatic circulation; they might have an effect on neonatal hyperbilirubinemia treatment. The objective of this study was to investigate the efficacy of Saccharomyces boulardii supplementation on hyperbilirubinemia. A prospective, double-blind, placebo controlled trial was performed on 35 to 42 gestational weeks' neonates. They were randomized either to receive feeding supplementation with S. boulardii 125 mg every 12 hours or placebo during phototherapy. Serum bilirubin levels were measured at 0, 24th, 48th, 72nd, and 96th hour of phototherapy. A total of 119 infants (61 in the control group and 58 in the study group) were enrolled. The duration of phototherapy (2 [1-3] vs. 2 [1-3], p: 0.22) was not different between groups. The levels of bilirubin during phototherapy ([24th hour; 14.1 {12.8-15.7} vs. 13.5 {12.4-14.9}, p: 0.085]; [48th hour; 14.1 {12-15.3} vs. 13.4 {12.4-14.5}, p: 0.41]; [72nd hour; 13.9 {12.2-15.6} vs. 13.5 {12.5-14.5}, p: 0.41]; [96th hour; 14.7 {11.4-15.5} vs. 13.4 {10.7-14.1}, p: 0.24]) or the duration of rebound phototherapy (1 [1-1] vs. 1.5 [1-2], p: 0.40) were lower in the study group than in the controls, but none of the values were statistically significant. S. boulardii did not influence the clinical course of hyperbilirubinemia significantly. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Effect of low-level laser therapy (LLLT) and light-emitting diodes (LEDT) applied during combined training on performance and post-exercise recovery: protocol for a randomized placebo-controlled trial.

PubMed

Machado, Aryane Flauzino; Micheletti, Jéssica Kirsch; Vanderlei, Franciele Marques; Nakamura, Fabio Yuzo; Leal-Junior, Ernesto Cesar Pinto; Netto Junior, Jayme; Pastre, Carlos Marcelo

Previous studies have shown positive results of phototherapy for improving performance and accelerating recovery; however, the effects of phototherapy during training and after a primary adaptation remain unclear. The aim of this randomized controlled trial is to analyze the effects of phototherapy and combined training on clinical, functional, and psychological outcomes and on vascular endothelial growth factor. This randomized placebo-controlled trial by stratified sample will involve 45 healthy male participants. In phase 1, the participants will undergo six weeks of combined training (sprints and squats). In phase 2, participants will be allocated through stratified randomization (based on adaptation capacity) into three groups: active phototherapy group (AG), placebo group (PG), and non-treatment control group (CG). A new six-week training program will then start and the participants will receive the recovery strategy between sprints and squats. The primary outcome will be maximal isometric contraction. The secondary outcomes include strength and power testing, maximal incremental test, squat jump, sprint test, muscle soreness, pain threshold, perceptions of exertion and recovery, psychological questionnaire, and vascular endothelial growth factor. This will be the first trial to include phototherapy during training. We believe that this strategy will combine the ergogenic and prophylactic effects in the same session. Furthermore, an application protocol performed after primary adaptation may reflect the real effect of the technique. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

A review of protocols for 308 nm excimer laser phototherapy in psoriasis.

PubMed

Mudigonda, Tejaswi; Dabade, Tushar S; Feldman, Steven R

2012-01-01

308 nm excimer laser phototherapy is efficacious in the treatment of localized psoriasis. Different approaches regarding dose fluency, number of treatments, and maintenance have been utilized, and there is yet to be a consensus on standard protocol. To characterize treatment parameters for 308 nm excimer laser phototherapy. We performed a PubMed search for studies describing excimer laser treatment protocol with particular attention to dosage determination, dose adjustment, dose fluency, number of treatments, and maintenance. Seven prospective studies were found describing the excimer efficacy for psoriasis. All studies determined the initial treatment dose using either the minimal erythema dose (MED) or induration. Fluency ranged from 0.5 MED (low) to 16 MED (high); one study demonstrated that medium to high fluencies yielded better improvement in fewer number of treatments. Fluency adjustments during the course of treatment were important to minimize phototherapy-associated side effects. The use of higher fluencies was reported to result in higher occurrences of blistering. One study implemented a maintenance tapering of dose-frequency phase to better manage psoriasis flare-ups. The 308 nm excimer laser is an effective therapy for psoriasis regardless of the method used to determine initial dosage, dose fluency, or number of treatments. As its usage as a targeted monotherapy increases, future trials should consider evaluating and modifying these parameters to determine the most optimal management of localized psoriasis. Based on our reviewed studies, there is no consensus for a single excimer laser therapy protocol and as a result, patient preferences should continue to be an important consideration for phototherapy regimen planning.

[Endonasal phototherapy in the treatment of allergic rhinitis].

PubMed

Demirbaş, Duygu; Aksoy, Elif; Polat, Senol; Serin, Gediz; Unal, Omer Faruk; Tanyeri, Hasan

2011-01-01

In this study, we assessed the effect of endonasal phototherapy on quality of life, nasal obstruction and the other symptoms in allergic rhinitis with visual analog scale (VAS), sinonasal outcome test-20 (SNOT-20), and acoustic rhinometry. Twenty-four patients (6 males, 18 females; mean age 41.3±13.0 years; range 20 to 60 years) suffering allergic rhinitis refractory to anti allergic drugs for at least two years were enrolled in the study. Each patient underwent a total of six sessions of endonasal phototherapy with Rhinolight (Rhinolight Ltd, Szeged, Hungary) performed three times a week for two weeks. During course of the investigation, additional therapy was not applied to any of the patients. Before and one month after treatment, patients completed visual analog scale and SNOT-20 forms and nasal obstruction was evaluated with acoustic rhinometry. After the treatment, the mean VAS score and the mean total SNOT-20 score were found lower than the results before the therapy (p=0.0001, p=0.0001). A significant decrease was found in the scores of sneezing, nasal discharge, postnasal drainage, coughing after treatment (p=0.0001). During objective evaluation of nasal obstruction with acoustic rhinometry, no statistically significant difference was found between pre- and post-treatment findings. Endonasal phototherapy is an effective modality in the treatment of symptomatology in allergic rhinitis patients refractory to antiallergic drugs. It is detected that endonasal phototherapy has positive effects on the quality of life. However, no effect on nasal obstruction was found with acoustic rhinometry which is an objective method.

Using antibody directed phototherapy to target oesophageal adenocarcinoma with heterogeneous HER2 expression

PubMed Central

Pye, Hayley; Butt, Mohammed Adil; Funnell, Laura; Reinert, Halla W.; Puccio, Ignazio; Rehman Khan, Saif U.; Saouros, Savvas; Marklew, Jared S.; Stamati, Ioanna; Qurashi, Maryam; Haidry, Rehan; Sehgal, Vinay; Oukrif, Dahmane; Gandy, Michael; Whitaker, Hayley C.; Rodriguez-Justo, Manuel; Novelli, Marco; Hamoudi, Rifat; Yahioglu, Gokhan; Deonarain, Mahendra P.; Lovat, Laurence B.

2018-01-01

Early oesophageal adenocarcinoma (OA) and pre-neoplastic dysplasia may be treated with endoscopic resection and ablative techniques such as photodynamic therapy (PDT). Though effective, discrete areas of disease may be missed leading to recurrence. PDT further suffers from the side effects of off-target photosensitivity. A tumour specific and light targeted therapeutic agent with optimised pharmacokinetics could be used to destroy residual cancerous cells left behind after resection. A small molecule antibody-photosensitizer conjugate was developed targeting human epidermal growth factor receptor 2 (HER2). This was tested in an in vivo mouse model of human OA using a xenograft flank model with clinically relevant low level HER2 expression and heterogeneity. In vitro we demonstrate selective binding of the conjugate to tumour versus normal tissue. Light dependent cytotoxicity of the phototherapy agent in vitro was observed. In an in vivo OA mouse xenograft model the phototherapy agent had desirable pharmacokinetic properties for tumour uptake and blood clearance time. PDT treatment caused tumour growth arrest in all the tumours despite the tumours having a clinically defined low/negative HER2 expression level. This new phototherapy agent shows therapeutic potential for treatment of both HER2 positive and borderline/negative OA. PMID:29796164

A multi-functional nanoplatform for tumor synergistic phototherapy

NASA Astrophysics Data System (ADS)

Zhang, Huijuan; Jiao, Xiaojing; Chen, Qianqian; Ji, Yandan; Zhang, Xiaoge; Zhu, Xing; Zhang, Zhenzhong

2016-02-01

Phototherapy, which mainly includes photothermal treatment (PTT) and photodynamic treatment (PDT), is a photo-initiated, noninvasive and effective approach for cancer treatment. The high accumulation of photosensitizers (PSs) in a targeted tumor is still a major challenge for efficient light conversion, to generate reactive oxygen species (ROS) and local hyperthermia. In this study, a simple and efficient hyaluronic acid (HA)-modified nanoplatform (HA-TiO2@MWCNTs) with high tumor-targeting ability, excellent phototherapy efficiency, low light-associated side effects and good water solubility was developed. It could be an effective carrier to load hematoporphyrin monomethyl ether (HMME), owing to the tubular conjugate structure. Apart from this, the as-prepared TiO2@MWCNTs nanocomposites could also be used as PSs for tumor PTT and PDT. Those results in vitro and in vivo showed that the anti-tumor effect of this system-mediated PTT/PDT were significantly better than those of single treatment manner. In addition, this drug delivery system could realize high ratio of drug loading, sustained drug release, prolonged circulation in vivo and active targeted accumulation in tumor. These results suggest that HA-TiO2@MWCNTs/HMME has high potential for tumor synergistic phototherapy as a smart theranostic nanoplatform.

FeOOH-loaded MnO2 nano-composite: An efficient emergency material for thallium pollution incident.

PubMed

Chen, Meiqing; Wu, Pingxiao; Yu, Langfeng; Liu, Shuai; Ruan, Bo; Hu, Haihui; Zhu, Nengwu; Lin, Zhang

2017-05-01

A FeOOH-loaded MnO 2 nano-composite was developed as an emergency material for Tl(I) pollution incident. Structural characterizations showed that FeOOH successfully loaded onto MnO 2 , the nanosheet-flower structure and high surface area (191 m 2  g -1 ) of material contributed to the excellent performance for Tl(I) removal. FeOOH-loaded MnO 2 with a Fe/Mn molar ratio of 1:2 exhibited a noticeable enhanced capacity for Tl(I) removal compared to that of pure MnO 2 . The outstanding performance for Tl(I) removal involves in extremely high efficiency (achieved equilibrium and drinking water standard within 4 min) and the large maximum adsorption capacity (450 mg g -1 ). Both the control-experiment and XPS characterization proved that the removal mechanism of Tl(I) on FeOOH-loaded MnO 2 included adsorption and oxidation: the oxidation of MnO 2 played an important role for Tl(I) removal, and the adsorption of FeOOH loaded on MnO 2 enhanced Tl(I) purification at the same time. In-depth purification of Tl(I) had reach drinking water standards (0.1 μg L -1 ) at pH above 7, and there wasn't security risk produced from the dissolution of Mn 2+ and Fe 2+ . Moreover, the as-prepared material could be utilized as a recyclable adsorbent regenerated by using NaOH-NaClO binary solution. Therefore, the synthesized FeOOH-loaded MnO 2 in this study has the potential to be applied as an emergency material for thallium pollution incident. Copyright © 2017 Elsevier Ltd. All rights reserved.

Protective effect of Fucoxanthin against UVB-induced skin photoaging in hairless mice.

PubMed

Urikura, Itaru; Sugawara, Tatsuya; Hirata, Takashi

2011-01-01

Fucoxanthin, a major carotenoid in brown algae, has various beneficial effects. In this study, we evaluated the effect of topical fucoxanthin on UVB-induced skin photoaging in hairless mice. The dorsal skins were treated topically with a 0.001% fucoxanthin solution 2 h each time before UVB irradiation (5 times a week) for 10 weeks. The formation of wrinkles in UVB-irradiated skin treated with vehicle alone significantly increased, as compared with the non-irradiated control. Treatment with fucoxanthin tended to suppress UVB-induced wrinkle formation, but there was no significant difference between wrinkle formation in the control group and the fucoxanthin treatment group. However, topical treatment with fucoxanthin significantly lessened UVB-induced epidermal hypertrophy, VEGF, and MMP-13 expression in the epidermis and thiobarbituric acid reactive substances (TBARS) in the skin. These results indicate that topical treatment with fucoxanthin prevents skin photoaging in UVB-irradiated hairless mice, possibly via antioxidant and antiangiogenic effects.

The Molecular and Physiological Responses of Physcomitrella patens to Ultraviolet-B Radiation1[W][OA

PubMed Central

Wolf, Luise; Rizzini, Luca; Stracke, Ralf; Ulm, Roman; Rensing, Stefan A.

2010-01-01

Ultraviolet-B (UV-B) radiation present in sunlight is an important trigger of photomorphogenic acclimation and stress responses in sessile land plants. Although numerous moss species grow in unshaded habitats, our understanding of their UV-B responses is very limited. The genome of the model moss Physcomitrella patens, which grows in sun-exposed open areas, encodes signaling and metabolic components that are implicated in the UV-B response in flowering plants. In this study, we describe the response of P. patens to UV-B radiation at the morphological and molecular levels. We find that P. patens is more capable of surviving UV-B stress than Arabidopsis (Arabidopsis thaliana) and describe the differential expression of approximately 400 moss genes in response to UV-B radiation. A comparative analysis of the UV-B response in P. patens and Arabidopsis reveals both distinct and conserved pathways. PMID:20427465

Effects of UV-B radiation on the isoflavone accumulation and physiological-biochemical changes of soybean during germination: Physiological-biochemical change of germinated soybean induced by UV-B.

PubMed

Ma, Meng; Wang, Pei; Yang, Runqiang; Gu, Zhenxin

2018-06-01

In this study, the effects of UV-B radiation on the isoflavones accumulation, physiological and nutritional quality, water status, and characteristics of proteins in germinated soybeans were investigated. The results showed that isoflavones content in soybeans increased with appropriate intensity and time of UV-B radiation and decreased with excessive treatment. Fresh weight, length, free amino acids, reducing sugar contents and bulk water (T 23 ) in germinated soybeans decreased with increasing radiation time, indicating that UV-B inhibited the growth and nutrients metabolism of soybean during germination. Cell damage was detected in germinated soybeans with excessive UV-B radiation, as shown by the black spots in cotyledons and the increased intercellular water determined by LF-NMR. Germination resulted in an increase in random coil structures, while UV-B radiation induced no obvious changes in FT-IR spectrum and protein conformation of soybeans. Both UV-B radiation and germination caused the increase in soluble proteins, especially in 1.0-75.0 kDa fraction. Copyright © 2018 Elsevier Ltd. All rights reserved.

Ultraviolet-B radiation increases serum 25-hydroxyvitamin D levels: the effect of UVB dose and skin color.

PubMed

Armas, Laura A G; Dowell, Susan; Akhter, Mohammed; Duthuluru, Sowjanya; Huerter, Christopher; Hollis, Bruce W; Lund, Richard; Heaney, Robert P

2007-10-01

Ultraviolet (UV)-B light increases vitamin D levels, but the dose response and the effect of skin pigmentation have not been well characterized. We sought to define the relationship between UVB exposure and 25-hydroxyvitamin D (25-OH-D) concentrations as a function of skin pigmentation. Seventy two participants with various skin tones had 90% of their skin exposed to UVB light (20-80 mJ/cm2) 3 times a week for 4 weeks. Serum 25-OH-D was measured weekly. Eighty percent of the variation in treatment response was explained by UVB dose and skin tone. Therapeutically important changes in 25-OH-D were achieved with minimal tanning. Four weeks was not long enough to reach a steady state at the higher dose rates. The response of 25-OH-D levels to UVB light is dependent on skin pigmentation and the amount of UVB given, and useful increases in vitamin D status can be achieved by defined UVB doses small enough to produce only minimal tanning.

Aligned metal absorbers and the ultraviolet background at the end of reionization

NASA Astrophysics Data System (ADS)

Doughty, Caitlin; Finlator, Kristian; Oppenheimer, Benjamin D.; Davé, Romeel; Zackrisson, Erik

2018-04-01

We use observations of spatially aligned C II, C IV, Si II, Si IV, and O I absorbers to probe the slope and intensity of the ultraviolet background (UVB) at z ˜ 6. We accomplish this by comparing observations with predictions from a cosmological hydrodynamic simulation using three trial UVBs applied in post-processing: a spectrally soft, fluctuating UVB calculated using multifrequency radiative transfer; a soft, spatially uniform UVB; and a hard, spatially uniform `quasars-only' model. When considering our paired high-ionization absorbers (C IV/Si IV), the observed statistics strongly prefer the hard, spatially uniform UVB. This echoes recent findings that cosmological simulations generically underproduce strong C IV absorbers at z > 5. A single low/high ionization pair (Si II/Si IV), by contrast, shows a preference for the HM12 UVB, whereas two more (C II/C IV and O I/C IV) show no preference for any of the three UVBs. Despite this, future observations of specific absorbers, particularly Si IV/C IV, with next-generation telescopes probing to lower column densities should yield tighter constraints on the UVB.

Sensitivity of two salamander (Ambystoma) species to ultraviolet radiation

USGS Publications Warehouse

Calfee, R.D.; Bridges, C.M.; Little, E.E.

2006-01-01

Increased ultraviolet-B (UV-B) radiation reaching the Earth's surface has been implicated in amphibian declines. Recent studies have shown that many amphibian species have differences in sensitivity depending on developmental stage. Embryos and larvae of Ambystoma maculatum (Spotted Salamander) and larvae of Ambystoma talpoideum (Mole Salamander) were exposed to five simulated UV-B treatments in controlled laboratory experiments to determine the relative sensitivity of different lifestages. Hatching success of the embryos exceeded 95% in all treatments; however, the larvae of both species exhibited greater sensitivity to UV-B exposure. Older larvae of A. maculatum that were not exposed to UV-B as embryos were more sensitive than larvae that had hatched during exposure to UV-B. Growth of surviving larvae of A. maculatum was significantly reduced as UV-B intensity increased, whereas growth of A. talpoideum was unaffected. These results were compared to ambient UV-B conditions in natural environments. It appears that the embryo stage is relatively unaffected by UV-B levels observed in natural habitats, probably because of protection from vegetation, organic matter in the water column, oviposition depth, and egg jelly. The larval stage of these species may be at greater risk, particularly if there is an increase in UV-B radiation exposure caused by increases in water clarity and/or decreases in dissolved organic carbon.

Interaction of COP1 and UVR8 regulates UV-B-induced photomorphogenesis and stress acclimation in Arabidopsis

PubMed Central

Favory, Jean-Jacques; Stec, Agnieszka; Gruber, Henriette; Rizzini, Luca; Oravecz, Attila; Funk, Markus; Albert, Andreas; Cloix, Catherine; Jenkins, Gareth I; Oakeley, Edward J; Seidlitz, Harald K; Nagy, Ferenc; Ulm, Roman

2009-01-01

The ultraviolet-B (UV-B) portion of the solar radiation functions as an environmental signal for which plants have evolved specific and sensitive UV-B perception systems. The UV-B-specific UV RESPONSE LOCUS 8 (UVR8) and the multifunctional E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) are key regulators of the UV-B response. We show here that uvr8-null mutants are deficient in UV-B-induced photomorphogenesis and hypersensitive to UV-B stress, whereas overexpression of UVR8 results in enhanced UV-B photomorphogenesis, acclimation and tolerance to UV-B stress. By using sun simulators, we provide evidence at the physiological level that UV-B acclimation mediated by the UV-B-specific photoregulatory pathway is indeed required for survival in sunlight. At the molecular level, we demonstrate that the wild type but not the mutant UVR8 and COP1 proteins directly interact in a UV-B-dependent, rapid manner in planta. These data collectively suggest that UV-B-specific interaction of COP1 and UVR8 in the nucleus is a very early step in signalling and responsible for the plant's coordinated response to UV-B ensuring UV-B acclimation and protection in the natural environment. PMID:19165148

UVB induces atypical melanocytic lesions and melanoma in human skin.

PubMed Central

Atillasoy, E. S.; Seykora, J. T.; Soballe, P. W.; Elenitsas, R.; Nesbit, M.; Elder, D. E.; Montone, K. T.; Sauter, E.; Herlyn, M.

1998-01-01

A direct causal relationship between ultraviolet (UV) light in the B range and melanoma development has not been demonstrated in humans; this study aims to establish causality. A total of 158 RAG-1 mice, grafted with human newborn foreskin, were separated into four groups and observed for a median of 10 months: 1) no treatment, 2) a single treatment with 7,12-dimethyl(a)benzanthracene (DMBA), 3) UVB irradiation at 500 J/m2 alone, three times weekly, and 4) a combination of DMBA and UVB. Twenty-three percent of 40 normal human skin grafts treated with UVB only and 38% of 48 grafts treated with the combination of DMBA and UVB developed solar lentigines within 5 to 10 months of treatment. Melanocytic hyperplasia was found in 73% of all UVB-treated xenografts. Histological melanocytic changes resembling lentigo and lentigo maligna were seen in several skin grafts treated with both DMBA and UVB. In one graft of an animal treated with a combination of DMBA and UVB, a human malignant melanoma, nodular type, developed. This experimental system demonstrates that chronic UVB irradiation with or without an initiating carcinogen can induce human melanocytic lesions, including melanoma. Images Figure 2 Figure 3 Figure 4 Figure 5 PMID:9588887

The influence of enhanced UV-B radiation on Batrachium trichophyllum and Potamogeton alpinus -- aquatic macrophytes with amphibious character.

PubMed

Germ, Mateja; Mazej, Zdenka; Gaberscik, Alenka; Häder, Donat P

2002-02-01

The responses of two amphibious species, Batrachium trichophyllum and Potamogeton alpinus to different UV-B environments were studied. Plant material from natural environments, as well as from outdoor treatments was examined. In long-term outdoor experiments plants were grown under three different levels of UV-B radiation: reduced and ambient UV-B levels, and a UV-B level simulating 17% ozone depletion. The following parameters were monitored: contents of total methanol soluble UV-absorbing compounds and chlorophyll a, terminal electron transport system (ETS) activity and optimal and effective quantum yield of photosystem II. No effect of the different UV-B levels on the measured parameters was observed. The amount of UV-B absorbing compounds seems to be saturated, since no differences were observed between treatments and no increase was found in peak season, when natural UV-B levels were the highest. Physiological measurements revealed no harmful effects; neither on potential and actual photochemical efficiency, nor on terminal ETS activity. The contents of UV-B absorbing compounds were examined also in plant material sampled in low and high altitude environments during the growth season. Both species exhibited no seasonal dynamics of production of UV-absorbing compounds. The contents were variable and showed no significant differences between high and low altitude populations.

Dandelion Extracts Protect Human Skin Fibroblasts from UVB Damage and Cellular Senescence

PubMed Central

Yang, Yafan; Li, Shuangshuang

2015-01-01

Ultraviolet (UV) irradiation causes damage in skin by generating excessive reactive oxygen species (ROS) and induction of matrix metalloproteinases (MMPs), leading to skin photoageing. Dandelion extracts have long been used for traditional Chinese medicine and native American medicine to treat cancers, hepatitis, and digestive diseases; however, less is known on the effects of dandelion extracts in skin photoageing. Here we found that dandelion leaf and flower extracts significantly protect UVB irradiation-inhibited cell viability when added before UVB irradiation or promptly after irradiation. Dandelion leaf and flower extracts inhibited UVB irradiation-stimulated MMP activity and ROS generation. Dandelion root extracts showed less action on protecting HDFs from UVB irradiation-induced MMP activity, ROS generation, and cell death. Furthermore, dandelion leaf and flower but not root extracts stimulated glutathione generation and glutathione reductase mRNA expression in the presence or absence of UVB irradiation. We also found that dandelion leaf and flower extracts help absorb UVB irradiation. In addition, dandelion extracts significantly protected HDFs from H2O2-induced cellular senescence. In conclusion, dandelion extracts especially leaf and flower extracts are potent protective agents against UVB damage and H2O2-induced cellular senescence in HDFs by suppressing ROS generation and MMP activities and helping UVB absorption. PMID:26576225

UVB-induced gene expression in the skin of Xiphophorus maculatus Jp 163 B☆

PubMed Central

Yang, Kuan; Boswell, Mikki; Walter, Dylan J.; Downs, Kevin P.; Gaston-Pravia, Kimberly; Garcia, Tzintzuni; Shen, Yingjia; Mitchell, David L.; Walter, Ronald B.

2014-01-01

Xiphophorus fish and interspecies hybrids represent long-standing models to study the genetics underlying spontaneous and induced tumorigenesis. The recent release of the Xiphophorus maculatus genome sequence will allow global genetic regulation studies of genes involved in the inherited susceptibility to UVB-induced melanoma within select backcross hybrids. As a first step toward this goal, we report results of an RNA-Seq approach to identify genes and pathways showing modulated transcription within the skin of X. maculatus Jp 163 B upon UVB exposure. X. maculatus Jp 163 B were exposed to various doses of UVB followed by RNA-Seq analysis at each dose to investigate overall gene expression in each sample. A total of 357 genes with a minimum expression change of 4-fold (p-adj < 0.05) were identified as responsive to UVB. The molecular genetic response of Xiphophorus skin to UVB exposure permitted assessment of; (1) the basal expression level of each transcript for each skin sample, (2) the changes in expression levels for each gene in the transcriptome upon exposure to increasing doses of UVB, and (3) clusters of genes that exhibit similar patterns of change in expression upon UVB exposure. These data provide a foundation for understanding the molecular genetic response of fish skin to UVB exposure. PMID:24556253

Exogenous indirect photoinactivation of bacterial pathogens and indicators in water with natural and synthetic photosensitizers in simulated sunlight with reduced UVB.

PubMed

Maraccini, P A; Wenk, J; Boehm, A B

2016-08-01

To investigate the UVB-independent and exogenous indirect photoinactivation of eight human health-relevant bacterial species in the presence of photosensitizers. Eight bacterial species were exposed to simulated sunlight with greatly reduced UVB light intensity in the presence of three synthetic photosensitizers and two natural photosensitizers. Inactivation curves were fit with shoulder log-linear or first-order kinetic models, from which the presence of a shoulder and magnitude of inactivation rate constants were compared. Eighty-four percent reduction in the UVB light intensity roughly matched a 72-95% reduction in the overall bacterial photoinactivation rate constants in sensitizer-free water. With the UVB light mostly reduced, the exogenous indirect mechanism contribution was evident for most bacteria and photosensitizers tested, although most prominently with the Gram-positive bacteria. Results confirm the importance of UVB light in bacterial photoinactivation and, with the reduction of the UVB light intensity, that the Gram-positive bacteria are more vulnerable to the exogenous indirect mechanism than Gram-negative bacteria. UVB is the most important range of the sunlight spectrum for bacterial photoinactivation. In aquatic environments where photosensitizers are present and there is high UVB light attenuation, UVA and visible wavelengths can contribute to exogenous indirect photoinactivation. © 2016 The Society for Applied Microbiology.

Malbec grape (Vitis vinifera L.) responses to the environment: Berry phenolics as influenced by solar UV-B, water deficit and sprayed abscisic acid.

PubMed

Alonso, Rodrigo; Berli, Federico J; Fontana, Ariel; Piccoli, Patricia; Bottini, Rubén

2016-12-01

High-altitude vineyards receive elevated solar ultraviolet-B (UV-B) levels so producing high quality berries for winemaking because of induction in the synthesis of phenolic compounds. Water deficit (D) after veraison, is a commonly used tool to regulate berry polyphenols concentration in red wine cultivars. Abscisic acid (ABA) plays a crucial role in the acclimation to environmental factors/signals (including UV-B and D). The aim of the present study was to evaluate independent and interactive effects of high-altitude solar UV-B, moderate water deficit and ABA applications on Vitis vinifera cv. Malbec berries. The experiment was conducted during two growing seasons with two treatments of UV-B (+UV-B and -UV-B), watering (+D and -D) and ABA (+ABA and -ABA), in a factorial design. Berry fresh weight, sugar content, fruit yield, phenolic compounds profile and antioxidant capacity (ORAC) were analyzed at harvest. Previous incidence of high UV-B prevented deleterious effects of water deficit, i.e. berry weight reduction and diminution of sugar accumulation. High UV-B increased total phenols (mainly astilbin, quercetin and kaempferol) and ORAC, irrespectively of the combination with other factors. Fruit yield was reduced by combining water deficit and high UV-B or water deficit and ABA. Two applications of ABA were enough to induced biochemical changes increasing total anthocyanins, especially those with higher antioxidant capacity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

UV-B Measurements in Mexico City: Comparison with Modeled UVB and Black Carbon

NASA Astrophysics Data System (ADS)

Marley, N. A.; Gaffney, J. S.; Frederick, J. E.

2004-12-01

Ultraviolet-B radiation (UV-B) represents a chemically important region of the sun's spectrum. At the earth's surface, UV-B can initiate a number of important photochemical reactions (e.g., ozone photolysis) that lead to the formation of OH radicals. Where levels of nitrogen oxides are high and reactive hydrocarbons are found, as in Mexico City and other megacities, UV-B can initiate photochemical smog formation. We used a broadband instrument to obtain UV-B measurements in Mexico City during the Mexico City Metropolitan Area 2003/Mexico City Megacity 2003 field study. We then used a simple radiation model for the Mexico City latitude, altitude, and time of year to construct UV-B contours for comparison with our results. Early morning discrepancies involve reductions in UV-B that are consistent with the presence of significant levels of BC in the Mexico City environment. During most afternoons, UV-B reductions were dominated by clouds. The results are discussed in terms of the potential impacts of BC on UV-B and downwind photochemical processes. The authors wish to thank the researchers at Centro Nacional de Investigación en Calidad Ambiental (CENICA), Mexico City. This work was supported by the U.S. Department of Energy, Atmospheric Science Program (Marley and Gaffney), and the U.S. Environmental Protection Agency (Frederick). We also wish to acknowledge Drs. Mario and Luisa Molina for their help in organizing and directing the Mexico City Metropolitan Area 2003 field study, during which these data were collected.

C/EBPα expression is downregulated in human nonmelanoma skin cancers and inactivation of C/EBPα confers susceptibility to UVB-induced skin squamous cell carcinomas.

PubMed

Thompson, Elizabeth A; Zhu, Songyun; Hall, Jonathan R; House, John S; Ranjan, Rakesh; Burr, Jeanne A; He, Yu-Ying; Owens, David M; Smart, Robert C

2011-06-01

Human epidermis is routinely subjected to DNA damage induced by UVB solar radiation. Cell culture studies have revealed an unexpected role for C/EBPα (CCAAT/enhancer-binding protein-α) in the DNA damage response network, where C/EBPα is induced following UVB DNA damage, regulates the G(1) checkpoint, and diminished or ablated expression of C/EBPα results in G(1) checkpoint failure. In the current study we observed that C/EBPα is induced in normal human epidermal keratinocytes and in the epidermis of human subjects exposed to UVB radiation. The analysis of human skin precancerous and cancerous lesions (47 cases) for C/EBPα expression was conducted. Actinic keratoses, a precancerous benign skin growth and precursor to squamous cell carcinoma (SCC), expressed levels of C/EBPα similar to normal epidermis. Strikingly, all invasive SCCs no longer expressed detectable levels of C/EBPα. To determine the significance of C/EBPα in UVB-induced skin cancer, SKH-1 mice lacking epidermal C/EBPα (CKOα) were exposed to UVB. CKOα mice were highly susceptible to UVB-induced SCCs and exhibited accelerated tumor progression. CKOα mice displayed keratinocyte cell cycle checkpoint failure in vivo in response to UVB that was characterized by abnormal entry of keratinocytes into S phase. Our results demonstrate that C/EBPα is silenced in human SCC and loss of C/EBPα confers susceptibility to UVB-induced skin SCCs involving defective cell cycle arrest in response to UVB.

C/EBPα Expression Is Downregulated in Human Nonmelanoma Skin Cancers and Inactivation of C/EBPα Confers Susceptibility to UVB-Induced Skin Squamous Cell Carcinomas

PubMed Central

Thompson, Elizabeth A.; Zhu, Songyun; Hall, Jonathan R.; House, John S.; Ranjan, Rakesh; Burr, Jeanne A.; He, Yu-Ying; Owens, David M.; Smart, Robert C.

2012-01-01

Human epidermis is routinely subjected to DNA damage induced by UVB solar radiation. Cell culture studies have revealed an unexpected role for C/EBPα (CCAAT/enhancer-binding protein-α) in the DNA damage response network, where C/EBPα is induced following UVB DNA damage, regulates the G1 checkpoint, and diminished or ablated expression of C/EBPα results in G1 checkpoint failure. In the current study we observed that C/EBPα is induced in normal human epidermal keratinocytes and in the epidermis of human subjects exposed to UVB radiation. The analysis of human skin precancerous and cancerous lesions (47 cases) for C/EBPα expression was conducted. Actinic keratoses, a precancerous benign skin growth and precursor to squamous cell carcinoma (SCC), expressed levels of C/EBPα similar to normal epidermis. Strikingly, all invasive SCCs no longer expressed detectable levels of C/EBPα. To determine the significance of C/EBPα in UVB-induced skin cancer, SKH-1 mice lacking epidermal C/EBPα (CKOα) were exposed to UVB. CKOα mice were highly susceptible to UVB-induced SCCs and exhibited accelerated tumor progression. CKOα mice displayed keratinocyte cell cycle checkpoint failure in vivo in response to UVB that was characterized by abnormal entry of keratinocytes into S phase. Our results demonstrate that C/EBPα is silenced in human SCC and loss of C/EBPα confers susceptibility to UVB-induced skin SCCs involving defective cell cycle arrest in response to UVB. PMID:21346772

Evidence that Singlet Oxygen-induced Human T Helper Cell Apoptosis Is the Basic Mechanism of Ultraviolet-A Radiation Phototherapy

PubMed Central

Morita, Akimichi; Werfel, Thomas; Stege, Helger; Ahrens, Constanze; Karmann, Karin; Grewe, Markus; Grether-Beck, Susanne; Ruzicka, Thomas; Kapp, Alexander; Klotz, Lars-Oliver; Sies, Helmut; Krutmann, Jean

1997-01-01

Ultraviolet A (UVA) irradiation is effectively used to treat patients with atopic dermatitis and other T cell mediated, inflammatory skin diseases. In the present study, successful phototherapy of atopic dermatitis was found to result from UVA radiation-induced apoptosis in skin-infiltrating T helper cells, leading to T cell depletion from eczematous skin. In vitro, UVA radiation-induced human T helper cell apoptosis was mediated through the FAS/FAS-ligand system, which was activated in irradiated T cells as a consequence of singlet oxygen generation. These studies demonstrate that singlet oxygen is a potent trigger for the induction of human T cell apoptosis. They also identify singlet oxygen generation as a fundamental mechanism of action operative in phototherapy. PMID:9362536

Transcriptomic Profiling of Soybean in Response to High-Intensity UV-B Irradiation Reveals Stress Defense Signaling

PubMed Central

Yoon, Min Young; Kim, Moon Young; Shim, Sangrae; Kim, Kyung Do; Ha, Jungmin; Shin, Jin Hee; Kang, Sungtaeg; Lee, Suk-Ha

2016-01-01

The depletion of the ozone layer in the stratosphere has led to a dramatic spike in ultraviolet B (UV-B) intensity and increased UV-B light levels. The direct absorption of high-intensity UV-B induces complex abiotic stresses in plants, including excessive light exposure, heat, and dehydration. However, UV-B stress signaling mechanisms in plants including soybean (Glycine max [L.]) remain poorly understood. Here, we surveyed the overall transcriptional responses of two soybean genotypes, UV-B-sensitive Cheongja 3 and UV-B-resistant Buseok, to continuous UV-B irradiation for 0 (control), 0.5, and 6 h using RNA-seq analysis. Homology analysis using UV-B-related genes from Arabidopsis thaliana revealed differentially expressed genes (DEGs) likely involved in UV-B stress responses. Functional classification of the DEGs showed that the categories of immune response, stress defense signaling, and reactive oxygen species (ROS) metabolism were over-represented. UV-B-resistant Buseok utilized phosphatidic acid-dependent signaling pathways (based on subsequent reactions of phospholipase C and diacylglycerol kinase) rather than phospholipase D in response to UV-B exposure at high fluence rates, and genes involved in its downstream pathways, such as ABA signaling, mitogen-activated protein kinase cascades, and ROS overproduction, were upregulated in this genotype. In addition, the DEGs for TIR-NBS-LRR and heat shock proteins are positively activated. These results suggest that defense mechanisms against UV-B stress at high fluence rates are separate from the photomorphogenic responses utilized by plants to adapt to low-level UV light. Our study provides valuable information for deep understanding of UV-B stress defense mechanisms and for the development of resistant soybean genotypes that survive under high-intensity UV-B stress. PMID:28066473

Different levels of UV-B resistance in Vaccinium corymbosum cultivars reveal distinct backgrounds of phenylpropanoid metabolites.

PubMed

Luengo Escobar, Ana; Magnum de Oliveira Silva, Franklin; Acevedo, Patricio; Nunes-Nesi, Adriano; Alberdi, Miren; Reyes-Díaz, Marjorie

2017-09-01

UV-B radiation induces several physiological and biochemical effects that can influence regulatory plant processes. Vaccinium corymbosum responds differently to UV-B radiation depending on the UV-B resistance of cultivars, according to their physiological and biochemical features. In this work, the effect of two levels of UV-B radiation during long-term exposure on the phenylpropanoid biosynthesis, and the expression of genes associated with flavonoid biosynthesis as well as the absolute quantification of secondary metabolites were studied in two contrasting UV-B-resistant cultivars (Legacy, resistant and Bluegold, sensitive). Multivariate analyses were performed to understand the role of phenylpropanoids in UV-B defense mechanisms. The amount of phenylpropanoid compounds was generally higher in Legacy than in Bluegold. Different expression levels of flavonoid biosynthetic genes for both cultivars were transiently induced, showing that even in longer period of UV-B exposure; plants are still adjusting their phenylpropanoids at the transcription levels. Multivariate analysis in Legacy indicated no significant correlation between gene expression and the levels of the flavonoids and phenolic acids. By contrast, in the Bluegold cultivar higher number of correlations between secondary metabolite and transcript levels was found. Taken together, the results indicated different adjustments between the cultivars for a successful UV-B acclimation. While the sensitive cultivar depends on metabolite adjustments to respond to UV-B exposure, the resistant cultivar also possesses an intrinsically higher antioxidant and UV-B screening capacity. Thus, we conclude that UV-B resistance involves not only metabolite level adjustments during the acclimation period, but also depends on the intrinsic metabolic status of the plant and metabolic features of the phenylpropanoid compounds. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Alteration of foliar flavonoid chemistry induced by enhanced UV-B radiation in field-grown Pinus ponderosa, Quercus rubra and Pseudotsuga menziesii.

PubMed

Warren, Jeffrey M; Bassman, John H; Mattinson, D Scott; Fellman, John K; Edwards, Gerald E; Robberecht, Ronald

2002-03-01

Chromatographic analyses of foliage from several tree species illustrate the species-specific effects of UV-B radiation on both quantity and composition of foliar flavonoids. Pinus ponderosa, Quercus rubra and Pseudotsuga menziesii were field-grown under modulated ambient (1x) and enhanced (2x) biologically effective UV-B radiation. Foliage was harvested seasonally over a 3-year period, extracted, purified and the flavonoid fraction applied to a mu Bondapak/C(18) column HPLC system sampling at 254 nm. Total flavonoid concentrations in Quercus rubra foliage were more than twice (leaf area basis) that of the other species; Pseudotsuga menziesii foliage had intermediate levels and P. ponderosa had the lowest concentrations of total flavonoids. No statistically significant UV-B radiation-induced effects were found in total foliar flavonoid concentrations for any species; however, concentrations of specific compounds within each species exhibited significant treatment effects. Higher (but statistically insignificant) levels of flavonoids were induced by UV-B irradiation in 1- and 2-year-old P. ponderosa foliage. Total flavonoid concentrations in 2-year-old needles increased by 50% (1x ambient UV-B radiation) or 70% (2x ambient UV-B radiation) from that of 1-year-old tissue. Foliar flavonoids of Q. rubra under enhanced UV-B radiation tended to shift from early-eluting compounds to less polar flavonoids eluting later. There were no clear patterns of UV-B radiation effects on 1-year-old P. menziesii foliage. However, 2-year-old tissue had slightly higher foliar flavonoids under the 2x UV-B radiation treatment compared to ambient levels. Results suggest that enhanced UV-B radiation will alter foliar flavonoid composition and concentrations in forest tree species, which could impact tissue protection, and ultimately, competition, herbivory or litter decomposition.

Solar UV-B radiation modulates chemical defenses against Anticarsia gemmatalis larvae in leaves of field-grown soybean.

PubMed

Dillon, Francisco M; Chludil, Hugo D; Zavala, Jorge A

2017-09-01

Although it is well known that solar ultraviolet B (UV-B) radiation enhances plant defenses, there is less knowledge about traits that define insect resistance in field-grown soybean. Here we study the effects of solar UV-B radiation on: a) the induction of phenolic compounds and trypsin proteinase inhibitors (TPI) in soybean undamaged leaves or damaged by Anticarsia gemmatalis neonates during six days, and b) the survival and mass gain of A. gemmatalis larvae that fed on soybean foliage. Two soybean cultivars (cv.), Charata and Williams, were grown under plastic with different transmittance to solar UV-B radiation, which generated two treatments: ambient UV-B (UVB+) and reduced UV-B (UVB-) radiation. Solar UV-B radiation decreased survivorship by 30% and mass gain by 45% of larvae that fed on cv. Charata, but no effect was found in those larvae that fed on cv. Williams. TPI activity and malonyl genistin were induced by A. gemmatalis damage in both cultivars, but solar UV-B radiation and damage only synergistically increased the induction of these compounds in cv. Williams. Although TPI activity and genistein derivatives were induced by herbivory, these results did not explain the differences found in survivorship and mass gain of larvae that fed on cv. Charata. However, we found a positive association between lower larval performance and the presence of two quercetin triglycosides and a kaempferol triglycoside in foliage of cv. Charata, which were identified by HPLC-DAD/MS 2 . We conclude that exclusion of solar UV-B radiation reduce resistance to A. gemmatalis, due to a reduction in flavonol concentration in a cultivar that has low levels of genistein derivatives like cv. Charata. Copyright © 2017 Elsevier Ltd. All rights reserved.

Apoptosis of Corneal Epithelial Cells Caused by Ultraviolet B-induced Loss of K+ is Inhibited by Ba2+

PubMed Central

Glupker, Courtney D.; Boersma, Peter M.; Schotanus, Mark P.; Haarsma, Loren D.; Ubels, John L.

2017-01-01

UVB exposure at ambient outdoor levels triggers rapid K+ loss and apoptosis in human corneal limbal epithelial (HCLE) cells cultured in medium containing 5.5 mM K+, but considerably less apoptosis occurs when the medium contains the high K+ concentration that is present in tears (25 mM). Since Ba2+ blocks several K+ channels, we tested whether Ba2+-sensitive K+ channels are responsible for some or all of the UVB-activated K+ loss and subsequent activation of the caspase cascade and apoptosis. Corneal epithelial cells in culture were exposed to UVB at 80 or 150 mJ/cm2. Patch-clamp recording was used to measure UVB-induced K+ currents. Caspase-activity and TUNEL assays were performed on HCLE cells exposed to UVB followed by incubation in the presence or absence of Ba2+. K+ currents were activated in HCLE cells following UVB-exposure. These currents were reversibly blocked by 5 mM Ba2+. When HCLE cells were incubated with 5 mM Ba2+ after exposure to UVB, activation of caspases-9, -8, and -3 and DNA fragmentation were significantly decreased. The data confirm that UVB-induced K+ current activation and loss of intracellular K+ leads to activation of the caspase cascade and apoptosis. Extracellular Ba2+ inhibits UVB-induced apoptosis by preventing loss of intracellular K+ when K+ channels are activated. Ba2+ therefore has effects similar to elevated extracellular K+ in protecting HCLE cells from UVB-induced apoptosis. This supports our overall hypothesis that elevated K+ in tears contributes to protection of the corneal epithelium from adverse effects of ambient outdoor UVB. PMID:27189864

Beneficial effects of solar UV-B radiation on soybean yield mediated by reduced insect herbivory under field conditions.

PubMed

Mazza, Carlos A; Giménez, Patricia I; Kantolic, Adriana G; Ballaré, Carlos L

2013-03-01

Ultraviolet-B radiation (UV-B: 280-315 nm) has damaging effects on cellular components and macromolecules. In plants, natural levels of UV-B can reduce leaf area expansion and growth, which can lead to reduced productivity and yield. UV-B can also have important effects on herbivorous insects. Owing to the successful implementation of the Montreal Protocol, current models predict that clear-sky levels of UV-B radiation will decline during this century in response to ozone recovery. However, because of climate change and changes in land use practices, future trends in UV doses are difficult to predict. In the experiments reported here, we used an exclusion approach to study the effects of solar UV-B radiation on soybean crops, which are extensively grown in many areas of the world that may be affected by future variations in UV-B radiation. In a first experiment, performed under normal management practices (which included chemical pest control), we found that natural levels of UV-B radiation reduced soybean yield. In a second experiment, where no pesticides were applied, we found that solar UV-B significantly reduced insect herbivory and, surprisingly, caused a concomitant increase in crop yield. Our data support the idea that UV-B effects on agroecosystems are the result of complex interactions involving multiple trophic levels. A better understanding of the mechanisms that mediate the anti-herbivore effect of UV-B radiation may be used to design crop varieties with improved adaptation to the cropping systems that are likely to prevail in the coming decades in response to agricultural intensification. Copyright © Physiologia Plantarum 2012.

Responses of He-Ne laser on agronomic traits and the crosstalk between UVR8 signaling and phytochrome B signaling pathway in Arabidopsis thaliana subjected to supplementary ultraviolet-B (UV-B) stress.

PubMed

Gao, Limei; Li, Yongfeng; Shen, Zhihua; Han, Rong

2018-05-01

UV-B acclimation effects and UV-B damage repair induced by a 632.8-nm He-Ne laser were investigated in Arabidopsis thaliana plants in response to supplementary UV-B stress. There was an increasing trend in growth parameters in the combination-treated plants with He-Ne laser and UV-B light compared to those stressed with enhanced UV-B light alone during different developmental stages of plants. The photosynthetic efficiency (Pn) and survival rates of seedlings were significantly higher in the combination treatments than UV-B stress alone. The expression of UVR8, phytochrome B (PhyB), and their mediated signal responsive genes such as COP1, HY5, and CHS were also significantly upregulated in plants with the laser irradiation compared with other groups without the laser. Levels of flavonol accumulation in leaves and capsule yield of He-Ne laser-treated plants were increased. The phyB-9 mutants were more sensitive to enhanced UV-B stress and had no obvious improvements in plant phenotypic development and physiological damage caused by enhanced UV-B stress after He-Ne laser irradiation. Our results suggested that UVR8 and its mediated signaling pathway via interaction with COP1 can be induced by He-Ne laser, and these processes were dependent on cytoplasmic PhyB levels in plant cells, which might be one of the most important mechanisms of He-Ne laser on UV-B protection and UV-B damage repair. These current data have also elucidated that the biostimulatory effects of He-Ne laser on Arabidopsis thaliana plants would happen not only during the early growth stage but also during the entire late developmental stage.

Ultraviolet radiation and the eye: an epidemiologic study.

PubMed Central

Taylor, H R

1989-01-01

Circumstantial evidence from biochemical, animal, and epidemiologic studies suggests an association between exposure to UV-B radiation (290 nm to 320 nm) and cataract. Such an association had not been proven because it had not been possible to quantify ocular UV-B exposure of individuals or to reliably grade the type and severity of cataract in field studies. We undertook an epidemiologic survey of cataract among 838 watermen who work on the Chesapeake Bay. Their individual ocular UV-B exposure was quantified for each year of life over the age of 16, on the basis of a detailed occupational history combined with laboratory and field measurements of ocular UV-B exposure. Cataracts were graded by both type and severity through clinical and photographic means. SMD changes were ascertained by fundal photography. A general medical history was taken to discover potentially confounding factors. This study showed that people with cortical lens opacities had a 21% higher UV-B exposure at each year of life than people without these opacities. A doubling in lifetime UV-B exposure led to a 60% increase in the risk of cortical cataract, and those with a high annual UV-B exposure increased their risk of cortical cataract over threefold. Corneal changes, namely pterygium and CDK, were also strongly associated with high UV-B exposure. No association was found between nuclear lens opacities or macular degeneration and UV-B exposure. This study also indicated several simple, practical measures, such as wearing spectacles or a hat, that effectively protect the eye from UV-B exposure. Thus it is easily within the power of individuals to protect their eyes from excessive UV-B exposure and reduce their risk of cortical cataract. A program of public education in this area could be a cost-effective means of reducing this important disease. PMID:2562534

The ethyl acetate fraction of Sargassum muticum attenuates ultraviolet B radiation-induced apoptotic cell death via regulation of MAPK- and caspase-dependent signaling pathways in human HaCaT keratinocytes.

PubMed

Piao, Mei Jing; Kim, Ki Cheon; Zheng, Jian; Yao, Cheng Wen; Cha, Ji Won; Boo, Sun Jin; Yoon, Weon Jong; Kang, Hee Kyoung; Yoo, Eun Sook; Koh, Young Sang; Ko, Mi Hee; Lee, Nam Ho; Hyun, Jin Won

2014-09-01

Our previous work demonstrated that an ethyl acetate extract derived from Sargassum muticum (Yendo) Fenshol (SME) protected human HaCaT keratinocytes against ultraviolet B (UVB)-induced oxidative stress by increasing antioxidant activity in the cells, thereby inhibiting apoptosis. The aim of the current study was to further elucidate the anti-apoptotic mechanism of SME against UVB-induced cell damage. The expression levels of several apoptotic-associated and mitogen-activated kinase (MAPK) signaling proteins were determined by western blot analysis of UVB-irradiated HaCaT cells with or without prior SME treatment. In addition, the loss of mitochondrial membrane potential (Δψm) was detected using flow cytometry or confocal microscopy and the mitochondria membrane-permeate dye, JC-1. Apoptosis was assessed by quantifying DNA fragmentation and apoptotic body formation. Furthermore, cell viability was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. SME absorbed electromagnetic radiation in the UVB range (280-320 nm) of the UV/visible light spectrum. SME also increased Bcl-2 and Mcl-1 expression in UVB-irradiated cells and decreased the Bax expression. Moreover, SME inhibited the UVB-induced disruption of mitochondrial membrane potential and prevented UVB-mediated increases in activated caspase-9 and caspase-3 (an apoptotic initiator and executor, respectively) levels. Notably, treatment with a pan-caspase inhibitor enhanced the anti-apoptotic effects of SME in UVB-irradiated cells. Finally, SME reduced the UVB-mediated phosphorylation of p38 MAPK and JNK, and prevented the UVB-mediated dephosphorylation of Erk1/2 and Akt. The present results indicate that SME safeguards HaCaT keratinocytes from UVB-mediated apoptosis by inhibiting a caspase-dependent signaling pathway.

Activation of T-cell Protein-tyrosine Phosphatase Suppresses Keratinocyte Survival and Proliferation following UVB Irradiation*

PubMed Central

Lee, Hyunseung; Morales, Liza D.; Slaga, Thomas J.; Kim, Dae Joon

2015-01-01

Chronic exposure to UV radiation can contribute to the development of skin cancer by promoting protein-tyrosine kinase (PTK) signaling. Studies show that exposure to UV radiation increases the ligand-independent activation of PTKs and induces protein-tyrosine phosphatase (PTP) inactivation. In the present work, we report that T-cell PTP (TC-PTP) activity is stimulated during the initial response to UVB irradiation, which leads to suppression of keratinocyte cell survival and proliferation via the down-regulation of STAT3 signaling. Our results show that TC-PTP-deficient keratinocyte cell lines expressed a significantly increased level of phosphorylated STAT3 after exposure to low dose UVB. This increase corresponded with increased cell proliferation in TC-PTP-deficient keratinocytes following UVB irradiation. Loss of TC-PTP also reduced UVB-induced apoptosis. Corroborating with these results, overexpression of TC-PTP in keratinocyte cell lines yielded a decrease in phosphorylated STAT3 levels, which corresponded with a significant decrease in cell proliferation in response to low dose UVB. We demonstrate that TC-PTP activity was increased upon UVB exposure, and overexpression of TC-PTP in keratinocyte cell lines further increased its activity in the presence of UVB. Treatment of TC-PTP-deficient keratinocytes with the STAT3 inhibitor STA21 significantly reduced cell viability following UVB exposure in comparison with untreated TC-PTP-deficient keratinocytes, confirming that the effect of TC-PTP on cell viability is mediated by STAT3 dephosphorylation. Combined, our results indicate that UVB-mediated activation of TC-PTP plays an important role in the STAT3-dependent regulation of keratinocyte cell proliferation and survival. Furthermore, these results suggest that TC-PTP may be a novel potential target for the prevention of UVB-induced skin cancer. PMID:25406309

Differential responses to high- and low-dose ultraviolet-B stress in tobacco Bright Yellow-2 cells

PubMed Central

Takahashi, Shinya; Kojo, Kei H.; Kutsuna, Natsumaro; Endo, Masaki; Toki, Seiichi; Isoda, Hiroko; Hasezawa, Seiichiro

2015-01-01

Ultraviolet (UV)-B irradiation leads to DNA damage, cell cycle arrest, growth inhibition, and cell death. To evaluate the UV-B stress–induced changes in plant cells, we developed a model system based on tobacco Bright Yellow-2 (BY-2) cells. Both low-dose UV-B (low UV-B: 740 J m−2) and high-dose UV-B (high UV-B: 2960 J m−2) inhibited cell proliferation and induced cell death; these effects were more pronounced at high UV-B. Flow cytometry showed cell cycle arrest within 1 day after UV-B irradiation; neither low- nor high-UV-B–irradiated cells entered mitosis within 12 h. Cell cycle progression was gradually restored in low-UV-B–irradiated cells but not in high-UV-B–irradiated cells. UV-A irradiation, which activates cyclobutane pyrimidine dimer (CPD) photolyase, reduced inhibition of cell proliferation by low but not high UV-B and suppressed high-UV-B–induced cell death. UV-B induced CPD formation in a dose-dependent manner. The amounts of CPDs decreased gradually within 3 days in low-UV-B–irradiated cells, but remained elevated after 3 days in high-UV-B–irradiated cells. Low UV-B slightly increased the number of DNA single-strand breaks detected by the comet assay at 1 day after irradiation, and then decreased at 2 and 3 days after irradiation. High UV-B increased DNA fragmentation detected by the terminal deoxynucleotidyl transferase dUTP nick end labeling assay 1 and 3 days after irradiation. Caffeine, an inhibitor of ataxia telangiectasia mutated (ATM) and ataxia telangiectasia and Rad3-related (ATR) checkpoint kinases, reduced the rate of cell death in high-UV-B–irradiated cells. Our data suggest that low-UV-B–induced CPDs and/or DNA strand-breaks inhibit DNA replication and proliferation of BY-2 cells, whereas larger contents of high-UV-B–induced CPDs and/or DNA strand-breaks lead to cell death. PMID:25954287

Cortisol Release in Response to UVB Exposure in Xiphophorus Fish

PubMed Central

Contreras, Adam J.; Boswell, Mikki; Downs, Kevin P.; Pasquali, Amanda; Walter, Ronald B.

2014-01-01

Xiphophorus fishes are comprised of 26 known species. Interspecies hybridization between select species has been utilized to produce experimental models to study melanoma development. Xiphophorus melanoma induction protocols utilize ultraviolet light (UVB) to induce DNA damage and associated downstream tumorigenesis. However, the impact of induced stress caused by the UVB treatment of the experimental animals undergoing tumor induction protocols has not been assessed. Stress is an adaptive physiological response to excessive or unpredictable environmental stimuli. The stress response in fishes may be measured by assay of cortisol released into the water. Here, we present results from investigations of stress response during experimental treatment and UVB exposure in X. maculatus Jp 163 B, X. couchianus, and F1 interspecies hybrids produced from the mating X. maculatus Jp 163 B x X. couchianus. Overall, cortisol release rates for males and females after UVB exposure showed no statistical differences. At lower UVB doses (8 and 16 kJ/m2), X. couchianus exhibited 2 fold higher levels of DNA damage then either X. maculatus or the F1 hybrid. However, based on cortisol release rates, none of the fish types tested induced a primary stress response at the UVB lower doses (8 and 16 kJ/m2). In contrast, at a very high UVB dose (32 kJ/m2) both X. maculatus and the F1 hybrid showed a 5 fold increase in cortisol release rate. To determine the effect of pigmentation on UVB induced stress, wild type and albino X. hellerii were exposed to UVB (32 kJ/m2). Albino X. hellerii exhibited 3.7 fold increase in cortisol release while wild type X. hellerii did not exhibit a significant cortisol response to UVB. Overall, the data suggest the rather low UVB doses often employed in tumour induction protocols do not induce a primary stress response in Xiphophorus fishes. PMID:24625568

Evaluating the combined effects of pretilachlor and UV-B on two Azolla species.

PubMed

Prasad, Sheo Mohan; Kumar, Sushil; Parihar, Parul; Singh, Anita; Singh, Rachana

2016-03-01

The present study assessed the comparative responses of two agronomic species of Azolla (A.microphylla and A. pinnata) exposed to man-made and natural stressors by evaluating biomass accumulation, pigments (chlorophyll a and b and carotenoid contents), photosynthetic activity and nitrogen metabolism. The study was carried out in field where two species of Azolla were cultured and treated with various concentrations (5, 10 and 20 μg ml(-1)) of herbicide; pretilachlor [2-chloro-2,6-diethyl-N-(2-propoxyethyl) acetanilide] and enhanced levels (UV-B1: ambient +2.2 kJ m(-2) day(-1) and UV-B2: ambient +4.4 kJ m(-2) day(-1)) of UV-B, alone as well as in combination. Biomass accumulation, photosynthetic pigments; chlorophyll a, b and carotenoids, photosynthetic oxygen yield and photosynthetic electron transport activities i.e. photosystem II (PS II) and photosystem I (PS I) in both the species declined with the increasing doses of pretilachlor and UV-B radiation, which further declined when applied in combination. The lower doses (5 and 10 μg ml(-1)) of pretilachlor and UV-B (UV-B1 and UV-B2) alone, damaged mainly the oxidation side of PS II, whereas higher dose (20 μg ml(-1)) of pretilachlor alone and in combination with UV-B1 and UV-B2 caused damage to PS II reaction centre and beyond this towards the reduction side. A significant enhancement in respiration was also noticed in fronds of both the Azolla species following pretilachlor and UV-B treatment, hence indicating strong damaging effect. The nitrate assimilating enzymes - nitrate reductase and nitrite reductase and ammonium assimilating enzymes - glutamine synthetase and glutamate synthase were also severely affected when treated either with pretilachlor and/or UV-B while glutamate dehydrogenase exhibited a stimulatory response. The study suggests that both the species of Azolla showed considerable damage under pretilachlor and UV-B treatments alone, however, in combination the effect was more intense. Further, in comparison to A. pinnata, A. microphylla exhibited greater resistance against tested doses of both the stresses, either alone or in combination. Copyright © 2015 Elsevier Inc. All rights reserved.

Photoprotection, photosynthesis and growth of tropical tree seedlings under near-ambient and strongly reduced solar ultraviolet-B radiation.

PubMed

Krause, G Heinrich; Jahns, Peter; Virgo, Aurelio; García, Milton; Aranda, Jorge; Wellmann, Eckard; Winter, Klaus

2007-10-01

Seedlings of two late-successional tropical rainforest tree species, Tetragastris panamensis (Engler) O. Kuntze and Calophyllum longifolium (Willd.), were field grown for 3-4 months at an open site near Panama City (9 degrees N), Panama, under plastic films that either transmitted or excluded most solar UV-B radiation. Experiments were designed to test whether leaves developing under bright sunlight with strongly reduced UV-B are capable of acclimating to near-ambient UV-B conditions. Leaves of T. panamensis that developed under near-ambient UV-B contained higher amounts of UV-absorbing substances than leaves of seedlings grown under reduced UV-B. Photosynthetic pigment composition, content of alpha-tocopherol, CO(2) assimilation, potential photosystem II (PSII) efficiency (evaluated by F(v)/F(m) ratios) and growth of T. panamensis and C. longifolium did not differ between seedlings developed under near-ambient and reduced solar UV-B. When seedlings were transferred from the reduced UV-B treatment to the near-ambient UV-B treatment, a pronounced inhibition of photosynthetic capacity was observed initially in both species. UV-B-mediated inhibition of photosynthetic capacity nearly fully recovered within 1 week of the transfer in C. longifolium, whereas in T. panamensis an about 35% reduced capacity of CO(2) uptake was maintained. A marked increase in UV-absorbing substances was observed in foliage of transferred T. panamensis seedlings. Both species exhibited enhanced mid-day photoinhibition of PSII immediately after being transferred from the reduced UV-B to the near-ambient UV-B treatment. This effect was fully reversible within 1d in T. panamensis and within a few days in C. longifolium. The data show that leaves of these tropical tree seedlings, when developing in full-spectrum sunlight, are effectively protected against high solar UV-B radiation. In contrast, leaves developing under conditions of low UV-B lacked sufficient UV protection. They experienced a decline in photosynthetic competence when suddenly exposed to near-ambient UV-B levels, but exhibited pronounced acclimative responses.

Enhanced UVB emission and analysis of chemical states of Ca5(PO4)3OH:Gd3+,Pr3+ phosphor prepared by co-precipitation

NASA Astrophysics Data System (ADS)

Mokoena, P. P.; Nagpure, I. M.; Kumar, Vinay; Kroon, R. E.; Olivier, E. J.; Neethling, J. H.; Swart, H. C.; Ntwaeaborwa, O. M.

2014-08-01

Hydroxyapatite (Ca5(PO4)3OH) is a well-known bioceramic material used in medical applications because of its ability to form direct chemical bonds with living tissues. This mineral is currently used as a host for rare-earth ions (e.g. Gd3+, Pr3+, Tb3+, etc.) to prepare phosphors that can be used in light emitting devices of different types. In this study Ca5(PO4)3OH:Gd3+,Pr3+ phosphors were prepared by the co-precipitation method and were characterised by x-ray diffraction, x-ray photoelectron spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, energy dispersive x-ray spectroscopy and photoluminescence spectroscopy. The x-ray diffraction pattern was consistent with the hexagonal phase of Ca5(PO4)3OH referenced in JCPDS card number 73-0293. The x-ray photoelectron spectroscopy data indicated that Ca2+ occupied two different lattice sites, referred to as Ca1 and Ca2. The photoluminescence data exhibited a narrowband emission located at 313 nm, which is associated with the 6P7/2→8S7/2 transition of the Gd3+ ion. This emission is classified as ultraviolet B and it is suitable for use in phototherapy lamps to treat various skin diseases. The photoluminescence intensity of the 313 nm emission was enhanced considerably by Pr3+ co-doping.

New apparatus with high radiation energy between 320-460 nm: physical description and dermatological applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mutzhas, M.F.; Holzle, E.; Hofmann, C.

1981-01-01

A new apparatus (UVASUN 5000) is presented with high-radiation energy between 320 to 460 nm. The measureable energy below 320 nm was shown to be many orders of magnitude too low to produce erythema. The radiator is a specially developed source for high uv-A intensity, housing a quartz bulb with a mixture of argon, mercury and metal-halides. At a skin-target distance of 0.2 m the size of the irradiated area is 0.35 x 0.35 m, and the measured mean uv-A intensity is about 1400 W. m-2 (140 mW . cm-2). The uv-A energy in the range of 320 to 400more » nm is about 84% of the total radiation energy. Effects of very high doses of uv-A on human skin were studied. Following single uv-a applications the minimal tanning dose uv-A (MTD) and the immediate pigment darkening (IPD) dose of uv-A were established. The calculated IPD threshold time was 1.8 min at 0.2 m. Repeated exposure to this uv-A delivering system yields long lasting dark brown skin pigmentation without any clinical or histological signs of sunburn (uv-B) damage, epidermal hyperplasia or thickening of the stratum corneum. The instrument was also successfully used for photo-patch testing and reproduction of skin lesions of polymorphous light eruption. Minimal therapeutic results were seen in the phototherapy of vitiligo and inflammatory acne.« less

Synthesis and TL/OSL properties of a novel high-sensitive blue-emitting LiSrPO4:Eu2+ phosphor for radiation dosimetry

NASA Astrophysics Data System (ADS)

Palan, C. B.; Koparkar, K. A.; Bajaj, N. S.; Soni, A.; Omanwar, S. K.

2016-07-01

In this study, a series of Eu2+-doped LiSrPO4 phosphors were synthesized via solid-state method. The structural and morphological characterizations were done through X-ray diffraction and scanning electronic microscope. Additionally, the photoluminescence (PL), thermoluminescence (TL) and optically stimulated luminescence (OSL) behaviours of LiSrPO4:Eu2+ phosphors were studied. The LiSrPO4:Eu2+ phosphor shows OSL sensitivity about 8 times than that of α-Al2O3:C phosphor and 6 times than that of LiMgPO4:Tb3+, B phosphor. Moreover, TL sensitivity was about 15 times more as compared to α-Al2O3:C phosphor. The kinetic parameters of TL curve were calculated using peak shape method. In TL/OSL mode, dose-response was almost linear nature, in the range of measurement. The minimum detectable dose was found to be 25.18 μGy with 3 σ of background. Also, reusability was also studies, which shows the phosphor can be reusable for 10 cycles with 0.1 % change in OSL output.

UV-observations with a Brewer spectrophotometer at Hohenpeissenberg

NASA Technical Reports Server (NTRS)

Vandersee, Winfried; Koehler, U.

1994-01-01

Regular spectral UV-B measurements with a Brewer spectrophotometer have been performed at Hohenpeissenberg since 1990. Intercomparison of the Brewer instrument with other UV-B monitoring devices have shown agreement to within plus or minus 10 percent. Comparisons of UV-B spectra measured on fair weather days reveal the well known increasing influence of ozone on UV-B irradiance with decreasing wavelengths. The integral amplification factor the erythemal irradiance reaches values up to 2.8, which can be diminished by increasing turbidity. The influence of cirrus cloud on the UV-B is also shown.

Resistance of a lizard (the green anole, Anolis carolinensis; Polychridae) to ultraviolet radiation-induced immunosuppression

USGS Publications Warehouse

Cope, R.B.; Fabacher, D.L.; Lieske, C.; Miller, C.A.

2001-01-01

The green anole (Anolis carolinensis) is the most northerly distributed of its Neotropical genus. This lizard avoids a winter hibernation phase by the use of sun basking behaviors. Inevitably, this species is exposed to high doses of ambient solar ultraviolet radiation (UVR). Increases in terrestrial ultraviolet-B (UV-B) radiation secondary to stratospheric ozone depletion and habitat perturbation potentially place this species at risk of UVR-induced immunosuppression. Daily exposure to subinflammatory UVR (8 kJ/m2/day UV-B, 85 kJ/m2/day ultraviolet A [UV-A]), 6 days per week for 4 weeks (total cumulative doses of 192 kJ/m2 UV-B, 2.04 × 103 kJ/m2 UV-A) did not suppress the anole's acute or delayed type hypersensitivity (DTH) response to horseshoe crab hemocyanin. In comparison with the available literature UV-B doses as low as 0.1 and 15.9 kJ/m2 induced suppression of DTH responses in mice and humans, respectively. Exposure of anoles to UVR did not result in the inhibition of ex vivo splenocyte phagocytosis of fluorescein labeled Escherichia coli or ex vivo splenocyte nitric oxide production. Doses of UV-B ranging from 0.35 to 45 kJ/m2 have been reported to suppress murine splenic/peritoneal macrophage phagocytosis and nitric oxide production. These preliminary studies demonstrate the resistance of green anoles to UVR-induced immunosuppression. Methanol extracts of anole skin contained two peaks in the ultraviolet wavelength range that could be indicative of photoprotective substances. However, the resistance of green anoles to UVR is probably not completely attributable to absorption by UVR photoprotective substances in the skin but more likely results from a combination of other factors including absorption by the cutis and absorption and reflectance by various components of the dermis.

Effects of phototherapy on muscle activity and pain in individuals with temporomandibular disorder: a study protocol for a randomized controlled trial.

PubMed

Herpich, Carolina Marciela; Leal-Junior, Ernesto Cesar Pinto; Amaral, Ana Paula; Tosato, Juliana de Paiva; Glória, Igor Phillip dos Santos; Garcia, Marília Barbosa Santos; Barbosa, Bruno Roberto Borges; El Hage, Yasmin; Arruda, Éric Edmur Camargo; Gomes, Cid Ándre Fidelis de Paula; Rodrigues, Monique Sampaio; de Sousa, Dowglas Fernando Magalhães; de Carvalho, Paulo de Tarso Camillo; Bussadori, Sandra Kalil; Gonzalez, Tabajara de Oliveira; Politti, Fabiano; Biasotto-Gonzalez, Daniela Aparecida

2014-12-16

According to the International Association for the Study of Pain (IASP), the term temporomandibular disorder (TMD) regards a subgroup of orofacial pain, the symptoms of which include pain or discomfort in the temporomandibular joint, ears, masticatory muscles and neck on one or both sides, as well as joint sounds, limited mandibular movements or mandibular deviation and difficulties chewing. Phototherapy, such as low-level laser therapy (LLLT) and light-emitting diode (LED) therapy, is one of the resources used to treatment muscle pain. Thus, there is a need to investigate therapeutic resources that combine different wavelengths as well as different light sources (LLLT and LED) in the same apparatus. The aim of the proposed study is to evaluate the effects of four different doses of phototherapy on pain, activity of the masticatory muscles (masseter and bilateral anterior temporal) and joint mobility in individuals with temporomandibular disorder. A further aim is to determine the cumulative effect 24 and 48 hours after a single session. A placebo-controlled, double-blind, randomized, clinical trial will be carried out involving 72 women between 18 and 40 years of age with a diagnosis of myogenous TMD. The participants will then be randomly allocated to four groups totaling 18 individuals per group. Three groups will be submitted to a single session of phototherapy with different light sources, and one group will receive placebo therapy: Group A (2.62 Joules); Group B (5.24 Joules); Group C (7.86 Joules); and Group D (0 Joules). The following assessment tools will be administered on four separate occasions (baseline and immediately after, 24 h after and 48 h after phototherapy). Pain intensity will be assessed using the visual analog scale for pain, while pain thresholds will be determined using algometer, and electromyographic (EMG) analysis on the masseter and anterior temporal muscles. The study will contribute to the practice of the evidence-based use of phototherapy in individuals with a myogenous TMD. Data will be published after the study is completed. This study is registered with the Brazilian Registry of Clinical Trials, NCT02018770, date of registration: 7 December 2013.

Maternal satisfaction with a novel filtered-sunlight phototherapy for newborn jaundice in Southwest Nigeria

PubMed Central

2014-01-01

Background In many resource-limited settings, the availability of effective phototherapy for jaundiced infants is frequently hampered by lack of, or inadequate resources to acquire and maintain conventional electric-powered phototherapy devices. This study set out to ascertain maternal experience and satisfaction with a novel treatment of infants with significant hyperbilirubinemia using filtered sunlight phototherapy (FSPT) in a tropical setting with irregular access to effective conventional phototherapy. Methods A cross-sectional satisfaction survey was conducted among mothers of jaundiced infants treated with FSPT in an inner-city maternity hospital in Lagos, Nigeria from November 2013 to March 2014. Mothers’ experience during treatment was elicited with a pretested questionnaire consisting of closed and open-ended items. Satisfaction was rated on a five-point Likert scale. Correlates of overall maternal satisfaction were explored with descriptive and inferential non-parametric statistics. Results A total of 191 mothers were surveyed, 77 (40%) of whom had no prior knowledge of neonatal jaundice. Maternal satisfaction was highest for quality of nursing care received (mean: 4.72 ± 0.55, median: 5[IQR: 5–5]) and lowest for physical state of the test environment (mean: 3.85 ± 0.74, median: 4[IQR: 3–4]). The overall rating (mean: 4.17 ± 0.58, median: 4[IQR: 4–5]) and the observed effect of FSPT on the babies (mean: 4.34 ± 0.58, 4[IQR: 4–5]) were quite satisfactory. FSPT experience was significantly correlated with the adequacy of information received (p < 0.0005), test environment (p = 0.002) and the observed effect of FSPT on the child (p < 0.0005). Almost all mothers (98.4%) indicated willingness to use FSPT in future or recommend it to others, although some (30 or 15.7%) disliked the idea of exposing newborns to sunlight. Conclusions Mothers of jaundiced newborns in this population are likely to be satisfied with FSPT where it is inevitable as an alternative to conventional electric-powered phototherapy. Adequate information, good test environment and friendly nursing care must be ensured for satisfactory maternal experience. PMID:25012576

Effect of laser phototherapy on human alveolar bone repair: micro tomographic and histomorphometrical analysis

NASA Astrophysics Data System (ADS)

Romão, Marcia M. A.; Marques, Márcia M.; Cortes, Arthur R. G.; Horliana, Anna C. R. T.; Moreira, Maria S.; Lascala, Cesar A.

2015-06-01

The immediate dental implant placement in the molars region is critical, because of the high amount of bone loss and the discrepancy between the alveolar crest thickness and the dental implant platform. Laser phototherapy (LPT) improves bone repair thus could accelerate the implant placement. Twenty patients were selected for the study. Ten patients were submitted to LPT with GaAlAs diode laser (808nm) during molar extraction, immediately after, 24h, 48h, 72h, 96h and 7 days. The irradiations were applied in contact and punctual mode (100mW, 0.04cm2, 0.75J/cm2, 30s per point, 3J per point). The control group (n=10) received the same treatment; however with the power of the laser off. Forty days later samples of the tissue formed inside the sockets were obtained for further microtomography (microCTs) and histomorphometry analyses. Data were compared by the Student t test, whereas those from the different microCT parameters were compared by the Pearson correlation test (p<0.05). The relative bone volume, as well as area was significantly higher (p<0.001) in the lased than the control group. In the control group there were negative correlations between number and thickness, and between number and separation of trabecula (p<0.01). Between thickness and separation of trabecula the correlation was positive (p<0.01). The laser group showed significant negative correlation between the number and the thickness of trabecula (p<0.01). LPT accelerated bone repair. By the Pearson correlation test it was possible to infer that the lased group presented a more homogeneous trabecular configuration, which would allow earlier dental implant placement.

Ultraviolet-B radiation modifies the quantitative and qualitative profile of flavonoids and amino acids in grape berries.

PubMed

Martínez-Lüscher, J; Torres, N; Hilbert, G; Richard, T; Sánchez-Díaz, M; Delrot, S; Aguirreolea, J; Pascual, I; Gomès, E

2014-06-01

Grapevine cv. Tempranillo fruit-bearing cuttings were exposed to supplemental ultraviolet-B (UV-B) radiation under controlled conditions, in order to study its effect on grape traits, ripening, amino acids and flavonoid profile. The plants were exposed to two doses of UV-B biologically effective (5.98 and 9.66kJm(-2)d(-1)), applied either from fruit set to ripeness or from the onset of veraison to ripeness. A 0kJm(-2)d(-1) treatment was included as a control. UV-B did not significantly modify grape berry size, but increased the relative mass of berry skin. Time to reach ripeness was not affected by UV-B, which may explain the lack of changes in technological maturity. The concentration of must extractable anthocyanins, colour density and skin flavonols were enhanced by UV-B, especially in plants exposed from fruit set. The quantitative and qualitative profile of grape skin flavonols were modified by UV-B radiation. Monosubstituted flavonols relative abundance increased proportionally to the accumulated UV-B doses. Furthermore, trisubstituted forms, which where predominant in non-exposed berries, were less abundant as UV-B exposure increased. Although total free amino acid content remained unaffected by the treatments, the increased levels of gamma-aminobutyric acid (GABA), as well as the decrease in threonine, isoleucine, methionine, serine and glycine, revealed a potential influence of UV-B on the GABA-mediated signalling and amino acid metabolism. UV-B had an overall positive impact on grape berry composition. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of enhanced ultraviolet-B radiation, water deficit, and their combination on UV-absorbing compounds and osmotic adjustment substances in two different moss species.

PubMed

Hui, Rong; Zhao, Ruiming; Song, Guang; Li, Yixuan; Zhao, Yang; Wang, Yanli

2018-05-01

A simulation experiment was conducted to explore the influence of enhanced ultraviolet-B (UV-B) radiation, water deficit, and their combination on UV-absorbing compounds and osmotic adjustment substances of mosses Bryum argenteum and Didymodon vinealis isolated from biological soil crusts (BSCs) growing in a revegetated area of the Tengger Desert, China. Four levels of UV-B radiation and two gradients of water regime were employed. Compared with their controls, amounts of total flavonoids, chlorophyll, carotenoids, soluble sugars, and soluble proteins significantly decreased (p < 0.05), but proline content significantly increased (p < 0.05), when exposed to either enhanced UV-B or water deficit. The negative effects of enhanced UV-B were alleviated when water deficit was applied. There were increases in UV-absorbing compounds and osmotic adjustment substances when exposed to a combination of enhanced UV-B and water deficit compared with single stresses, except for the proline content in D. vinealis. In addition, our results also indicated interspecific differences in response to enhanced UV-B, water deficit, and their combination. Compared with B. argenteum, D. vinealis was more resistant to enhanced UV-B and water deficit singly and in combination. These results suggest that the damage of enhanced UV-B on both species might be alleviated by water deficit. This alleviation is important for understanding the response of BSCs to UV-B radiation in future global climate change. This also provides novel insights into assessment damages of UV-B to BSC stability in arid and semiarid regions.

The endogenous hormones in soybean seedlings under the joint actions of rare earth element La(III) and ultraviolet-B stress.

PubMed

Peng, Qi; Zhou, Qing

2009-12-01

The dynamic state of endogenous hormone content in soybean seedlings was investigated for a further demonstration of alleviating the damage of the ultraviolet ultraviolet-B (UV-B) radiation in the La(III)-treated soybean seedlings under UV-B stress. Using hydroponics culture, the effects of lanthanum(III) on the contents of endogenous hormone under elevated ultraviolet-B radiation (280–320 nm) was studied. The results showed that the content of indole-3-acetic acid (IAA) in soybean seedlings decreased initially and then increased when the seedlings underwent UV-B treatment during the stress and convalescent period; this was compared with a control; acetic acid oxidase (IAAO) activity increased at first (first to fifth day) and then decreased (sixth to 11th day). A similar change of abscisic acid content and IAAO content in soybean seedlings occurred; gibberellic acid (GA) content decreased during the experiment compared with control. The content of IAA and GA in soybean seedlings with La(III) + UV-B treatment was higher than those of UV-B treatment; IAAO activity and GA content in soybean seedlings with La (III) + UV-B treatment were lower than those of UV-B treatment. It suggested that the regulative effect of La(III) at the optimum concentration on endogenous hormone improved the ability of plant stress resistance, and its protective effect against low UV-B radiation was superior to high UV-B radiation. The defensive effect of La(III) on soybean seedlings under UV-B stress was carried out on the layer of defense system.

On induced-modifications in optical properties of Makrofol® DE 1-1 SSNTD by UVB and UVA

NASA Astrophysics Data System (ADS)

Al-Amri, A.; El Ghazaly, M.; Abdel-Aal, M. S.

The induced modifications in the optical properties of Makrofol® DE 1-1 solid state nuclear track detectors upon irradiation by UVB (302 nm) and UVA (365 nm) were characterized and compared. Makrofol® DE 1-1 detectors were irradiated separately for different durations with UVB (302 nm) and UVA (365 nm). The measurements revealed insignificant changes were observed at all in UVA (365 nm)-irradiated Makrofol® DE 1-1, irrespective the irradiation time (dose). All UVB (302 nm)-irradiated Makrofol® DE 1-1 detectors show a substantial red shift in UV-Vis spectra and a continuous increase in absorbance as the exposure time (Dose) to UVB increases. UVC-irradiated Makrofol® DE 1-1 exhibits absorption bands at 315 ± 5 nm in UV-visible spectra. The absorption increases exponential with the increasing the UVB irradiation time gets saturated started from 75 h to 400 h. In the visible light range no significant changes were observed in Makrofol® DE 1-1 detector irrespective the exposure time to UVB of 302 nm. It is found that the direct band gap is higher than indirect band gap and both decrease with the increase in the irradiation time of UVB of 302 nm. The obtained results of the Urbach energy and carbon atoms per cluster indicate that both increase with the increase in the irradiation time to UVB (302 nm). The induced modification in the optical properties of Makrofol® DE 1-1 can be used in UVB dosimetry, meanwhile it is not applicable for UVA of 365 nm.

Molecular Insights into SIRT1 Protection Against UVB-Induced Skin Fibroblast Senescence by Suppression of Oxidative Stress and p53 Acetylation.

PubMed

Chung, Ki Wung; Choi, Yeon Ja; Park, Min Hi; Jang, Eun Ji; Kim, Dae Hyun; Park, Byung Hyun; Yu, Byung Pal; Chung, Hae Young

2015-08-01

Stresses, such as exposure to ultraviolet radiation and those associated with aging, are known to cause premature cellular senescence that is characterized by growth arrest and morphological and gene expression changes. This study was designed to investigate the protective effect of Sirtuin1 (SIRT1) on the UVB-induced premature senescence. Under in vitro experimental conditions, exposure to a subcytotoxic dose of UVB enhanced human skin fibroblasts senescence, as characterized by increased β-galactosidase activity and increased levels of senescence-associated proteins. However, adenovirus-mediated SIRT1 overexpression significantly protected fibroblasts from UVB-induced cellular deterioration. Exposure to UVB-induced cell senescence was associated with oxidative stress and p38 mitogen-activated protein kinase activation. Molecular analysis demonstrated that deacetylation of Forkhead box O3α (FOXO3α) by SIRT1 changed the transcriptional activity of FOXO3α and increased resistance to the oxidative stress. In addition, SIRT1 suppressed UVB-induced p53 acetylation and its transcriptional activity, which directly affected the cell cycle arrest induced by UVB. Further study demonstrated that SIRT1 activation inhibited cell senescence in the skin of the HR1 hairless mouse exposed to UVB. The study identifies a new role for SIRT1 in the UVB-induced senescence of skin fibroblats and provides a potential target for skin protection through molecuar insights into the mechanisms responsible for UVB-induced photoaging. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Photoprotective effects of topical ginseng leaf extract using Ultraflo L against UVB-induced skin damage in hairless mice.

PubMed

Hong, Yang Hee; Lee, Hyun-Sun; Jung, Eun Young; Han, Sung-Hee; Park, Yooheon; Suh, Hyung Joo

2017-10-01

Abnormal activation of matrix metalloproteinases (MMPs) plays an important role in UV-induced wrinkle formation, which is a major dermatological problem. This formation occurs due to the degeneration of the extracellular matrix (ECM). In this study, we investigated the cutaneous photoprotective effects of Ultraflo L treated ginseng leaf (UTGL) in hairless mice. SKH-1 hairless mice (6 weeks of age) were randomly divided into four groups (8 mice/group). UTGL formulation was applied topically to the skin of the mice for 10 weeks. The normal control group received nonvehicle and was not irradiated with UVB. The UV control (UVB) group received nonvehicle and was exposed to gradient-UVB irradiation. The groups (GA) receiving topical application of UTGL formulation were subjected to gradient-UVB irradiation on 0.5 mg/cm 2 [GA-low (GA-L)] and 1.0 mg/cm 2 [(GA-high (GA-H)] of dorsal skin area, respectively. We found that topical treatment with UTGL attenuated UVB-induced epidermal thickness and impairment of skin barrier function. Additionally, UTGL suppressed the expression of MMP-2, -3, and -13 induced by UVB irradiation. Our results show that topical application of UTGL protects the skin against UVB-induced damage in hairless mice and suggest that UTGL can act as a potential agent for preventing and/or treating UVB-induced photoaging. UTGL possesses sunscreen properties and may exhibit photochemoprotective activities inside the skin of mice. Therefore, UTGL could be used as a potential therapeutic agent to protect the skin against UVB-induced photoaging.

Induction of IL-10 gene expression in human keratinocytes by UVB exposure in vivo and in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Enk, C.D.; Blauvelt, A.; Katz, S.I.

Numerous studies have demonstrated that ultraviolet B (UVB) irradiation has profound effects on the skin and systemic immune systems. Because many of the effects of UVB result in suppression of contact sensitivity responses and because IL-10 induces a Th2 rather than a Th1 response, we sought to determine whether UVB irradiation induces IL-10 transcription and subsequent protein secretion by human epidermal cells. Skin of nine volunteers was exposed to UVB or sham irradiation, and epidermal cell suspensions were prepared from suction blister roofs 24 h thereafter. mRNA was extracted using oligo dT-coated magnetic beads, and IL-10 cDNA was amplified withmore » a sensitive RT-PCR technique. We found that IL-10 was constitutively expressed by epidermal cells in 5 of 9 volunteers and that IL-10 message was up-regulated by UVB exposure in all experiments. Since epidermis consists of a heterogeneous cell population with distinct cytokine profiles, we determined whether UVB caused enhanced IL-10 transcription and protein secretion in human keratinocyte cultures. In these experiments, IL-10 was constitutively expressed by keratinocytes and UVB up-regulated IL-10 gene expression in a dose-dependent manner 24 h after in vitro irradiation, coinciding with IL-10 protein secretion into the culture supernatants. Taken together, the findings indicate that UVB irradiation induces IL-10 in human keratinocytes and suggest that keratinocyte-derived IL-10 may be an important component of the immunosuppression that results from UVB irradiation. 55 refs., 5 figs.« less

Short- and long-term physiological responses of grapevine leaves to UV-B radiation.

PubMed

Martínez-Lüscher, J; Morales, F; Delrot, S; Sánchez-Díaz, M; Gomés, E; Aguirreolea, J; Pascual, I

2013-12-01

The present study aimed at evaluating the short- and long-term effects of UV-B radiation on leaves of grapevine Vitis vinifera (cv. Tempranillo). Grapevine fruit-bearing cuttings were exposed to two doses of supplemental biologically effective UV-B radiation (UV-BBE) under glasshouse-controlled conditions: 5.98 and 9.66kJm(-2)d(-1). The treatments were applied either for 20d (from mid-veraison to ripeness) or 75d (from fruit set to ripeness). A 0kJm(-2)d(-1) UV-B treatment was included as control. The main effects of UV-B were observed after the short-term exposure (20d) to 9.66kJm(-2)d(-1). Significant decreases in net photosynthesis, stomatal conductance, sub-stomatal CO2 concentration, the actual photosystem II (PSII) efficiency, total soluble proteins and de-epoxidation state of the VAZ cycle were observed, whereas the activities of several antioxidant enzymes increased significantly. UV-B did not markedly affect dark respiration, photorespiration, the maximum potential PSII efficiency (Fv/Fm), non-photochemical quenching (NPQ), as well as the intrinsic PSII efficiency. However, after 75d of exposure to 5.98and 9.66kJm(-2)d(-1) UV-B most photosynthetic and biochemical variables were unaffected and there were no sign of oxidative damage in leaves. The results suggest a high long-term acclimation capacity of grapevine to high UV-B levels, associated with a high accumulation of UV-B absorbing compounds in leaves, whereas plants seemed to be tolerant to moderate doses of UV-B. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

HAC1 and HAF1 Histone Acetyltransferases Have Different Roles in UV-B Responses in Arabidopsis.

PubMed

Fina, Julieta P; Masotti, Fiorella; Rius, Sebastián P; Crevacuore, Franco; Casati, Paula

2017-01-01

Arabidopsis has 12 histone acetyltransferases grouped in four families: the GNAT/HAG, the MYST/HAM, the p300/CBP/HAC and the TAFII250/HAF families. We previously showed that ham1 and ham2 mutants accumulated higher damaged DNA after UV-B exposure than WT plants. In contrast, hag3 RNA interference transgenic plants showed less DNA damage and lower inhibition of plant growth by UV-B, and increased levels of UV-B-absorbing compounds. These results demonstrated that HAM1, HAM2, and HAG3 participate in UV-B-induced DNA damage repair and signaling. In this work, to further explore the role of histone acetylation in UV-B responses, a putative function of other acetyltransferases of the HAC and the HAF families was analyzed. Neither HAC nor HAF acetyltrasferases participate in DNA damage and repair after UV-B radiation in Arabidopsis. Despite this, haf1 mutants presented lower inhibition of leaf and root growth by UV-B, with altered expression of E2F transcription factors. On the other hand, hac1 plants showed a delay in flowering time after UV-B exposure and changes in FLC and SOC1 expression patterns. Our data indicate that HAC1 and HAF1 have crucial roles for in UV-B signaling, confirming that, directly or indirectly, both enzymes also have a role in UV-B responses.

Influence of total organic carbon and UV-B radiation on zinc toxicity and bioaccumulation in aquatic communities.

PubMed

Kashian, Donna R; Prusha, Blair A; Clements, William H

2004-12-01

The effects of total organic carbon (TOC) and UV-B radiation on Zn toxicity and bioaccumulation in a Rocky Mountain stream community were assessed in a 10-d microcosm experiment. We predicted that TOC would mitigate Zn toxicity and that the combined effects of Zn and UV-B would be greater than Zn alone. However, TOC did not mitigate Zn toxicity in this study. In fact, treatments with TOC plus Zn had significantly lower community respiration as compared with the controls and Zn concentrations associated with the periphyton increased in the presence of TOC. UV-B had no additive effect on periphyton Zn accumulation or community respiration. Heptageniid mayflies (Ephemeroptera) were particularly sensitive to Zn, and reduced abundances were observed in all Zn treatments. UV-B did not additionally impact Heptageniid abundances; however UV-B did have a greater effect on macroinvertebrate drift than Zn alone. Ephemeroptera, Plecoptera, and Trichoptera (groups typically classified as sensitive to disturbance) were found in highest numbers in the drift of UV-B + Zn treatments. Measures of Zn accumulation in the caddisfly Arctopsyche grandis, periphyton biomass, and total macroinvertebrate abundance were not sufficiently sensitive to differentiate effects of TOC, UV-B, and Zn. These results indicate that UV-B and TOC affect Zn bioavailability and toxicity by impacting species abundance, behavior, and ecosystem processes.

Fisetin inhibits UVB-induced cutaneous inflammation and activation of PI3K/AKT/NFκB signaling pathways in SKH-1 hairless mice†

PubMed Central

Pal, Harish Chandra; Athar, Mohammad; Elmets, Craig A.; Afaq, Farrukh

2014-01-01

Solar ultraviolet B (UVB) radiation has been shown to induce inflammation, DNA damage, p53 mutations, and alterations in signaling pathways eventually leading to skin cancer. In the present study, we investigated whether fisetin reduces inflammatory responses and modulates PI3K/AKT/NFκB cell survival signaling pathways in UVB exposed SKH-1 hairless mouse skin. Mice were exposed to 180 mJ/cm2 of UVB radiation on alternate days for a total of seven exposures, and fisetin (250 and 500 nmol) was applied topically after 15 min of each UVB exposure. Fisetin treatment to UVB exposed mice resulted in decreased hyperplasia and reduced infiltration of inflammatory cells. Fisetin treatment also reduced inflammatory mediators such as COX-2, PGE2 as well as its receptors (EP1- EP4), and MPO activity. Furthermore, fisetin reduced the level of inflammatory cytokines TNFα, IL-1β and IL-6 in UVB exposed skin. Fisetin treatment also reduced cell proliferation markers as well as DNA damage as evidenced by increased expression of p53 and p21 proteins. Further studies revealed that fisetin inhibited UVB-induced expression of PI3K, phosphorylation of AKT, and activation of the NFκB signaling pathway in mouse skin. Overall, these data suggest that fisetin may be useful against UVB-induced cutaneous inflammation and DNA damage. PMID:25169110

Gardenia jasminoides Extract Attenuates the UVB-Induced Expressions of Cytokines in Keratinocytes and Indirectly Inhibits Matrix Metalloproteinase-1 Expression in Human Dermal Fibroblasts

PubMed Central

Seok, Jin Kyung; Suh, Hwa-Jin

2014-01-01

Ultraviolet radiation (UV) is a major cause of photoaging, which also involves inflammatory cytokines and matrix metalloproteinases (MMP). The present study was undertaken to examine the UVB-protecting effects of yellow-colored plant extracts in cell-based assays. HaCaT keratinocytes were exposed to UVB in the absence or presence of plant extracts, and resulting changes in cell viability and inflammatory cytokine expression were measured. Of the plant extracts tested, Gardenia jasminoides extract showed the lowest cytotoxicity and dose-dependently enhanced the viabilities of UVB-exposed cells. Gardenia jasminoides extract also attenuated the mRNA expressions of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in HaCaT cells stimulated by UVB. Conditioned medium from UVB-exposed HaCaT cells was observed to stimulate MMP-1 protein expression in human dermal fibroblasts, and this effect was much smaller for the conditioned medium of HaCaT cells exposed to UVB in the presence of Gardenia jasminoides extract. Gardenia jasminoides extract also exhibited antioxidative and antiapoptotic effects in HaCaT cells exposed to UVB. These results indicated that UVB-induced injury and inflammatory responses of skin cells can be attenuated by yellow-colored plant extracts, such as Gardenia jasminoides extract. PMID:24711853

Chemopreventive apigenin controls UVB-induced cutaneous proliferation and angiogenesis through HuR and thrombospondin-1

PubMed Central

Veliceasa, Dorina; Bridgeman, Bryan B.; Fitchev, Philip; Cornwell, Mona L.; Crawford, Susan E.; Pelling, Jill C.; Volpert, Olga V.

2014-01-01

Plant flavonoid apigenin prevents and inhibits UVB-induced carcinogenesis in the skin and has strong anti-proliferative and anti-angiogenic properties. Here we identify mechanisms, by which apigenin controls these oncogenic events. We show that apigenin acts, at least in part, via endogenous angiogenesis inhibitor, thrombospondin-1 (TSP1). TSP1 expression by the epidermal keratinocytes is potently inhibited by UVB. It inhibits cutaneous angiogenesis and UVB-induced carcinogenesis. We show that apigenin restores TSP1 in epidermal keratinocytes subjected to UVB and normalizes proliferation and angiogenesis in UVB-exposed skin. Importantly, reconstituting TSP1 anti-angiogenic function in UVB-irradiated skin with a short bioactive peptide mimetic representing exclusively its anti-angiogenic domain reproduced the anti-proliferative and anti-angiogenic effects of apigenin. Cox-2 and HIF-1α are important mediators of angiogenesis. Both apigenin and TSP1 peptide mimetic attenuated their induction by UVB. Finally we identified the molecular mechanism, whereby apigenin did not affect TSP1 mRNA, but increased de novo protein synthesis. Knockdown studies implicated the RNA-binding protein HuR, which controls mRNA stability and translation. Apigenin increased HuR cytoplasmic localization and physical association with TSP1 mRNA causing de novo TSP1 synthesis. HuR cytoplasmic localization was, in turn, dependent on CHK2 kinase. Together, our data provide a new mechanism, by which apigenin controls UVB-induced carcinogenesis. PMID:25526033

HAC1 and HAF1 Histone Acetyltransferases Have Different Roles in UV-B Responses in Arabidopsis

PubMed Central

Fina, Julieta P.; Masotti, Fiorella; Rius, Sebastián P.; Crevacuore, Franco; Casati, Paula

2017-01-01

Arabidopsis has 12 histone acetyltransferases grouped in four families: the GNAT/HAG, the MYST/HAM, the p300/CBP/HAC and the TAFII250/HAF families. We previously showed that ham1 and ham2 mutants accumulated higher damaged DNA after UV-B exposure than WT plants. In contrast, hag3 RNA interference transgenic plants showed less DNA damage and lower inhibition of plant growth by UV-B, and increased levels of UV-B-absorbing compounds. These results demonstrated that HAM1, HAM2, and HAG3 participate in UV-B-induced DNA damage repair and signaling. In this work, to further explore the role of histone acetylation in UV-B responses, a putative function of other acetyltransferases of the HAC and the HAF families was analyzed. Neither HAC nor HAF acetyltrasferases participate in DNA damage and repair after UV-B radiation in Arabidopsis. Despite this, haf1 mutants presented lower inhibition of leaf and root growth by UV-B, with altered expression of E2F transcription factors. On the other hand, hac1 plants showed a delay in flowering time after UV-B exposure and changes in FLC and SOC1 expression patterns. Our data indicate that HAC1 and HAF1 have crucial roles for in UV-B signaling, confirming that, directly or indirectly, both enzymes also have a role in UV-B responses. PMID:28740501

The gender differences in the inhibitory action of UVB-induced melanocyte activation by the administration of tranexamic acid.

PubMed

Hiramoto, Keiichi; Yamate, Yurika; Sugiyama, Daijiro; Takahashi, Yumi; Mafune, Eiichi

2016-05-01

Tranexamic acid has an inhibitory action on ultraviolet (UV) B-induced melanocyte activation. This study examined the sex differences in the inhibitory action of tranexamic acid on UVB-induced melanocyte activation. We irradiated the eye and ear of male and female mice with UVB at a dose of 1.0 kJ/m(2) using a 20SE sunlamp. We orally administered tranexamic acid (750 mg/kg/day) at 30 min before UVB exposure. Tranexamic acid inhibited the UVB-induced epidermal melanocyte activation, and the effect was more remarkable under UVB eye irradiation than under UVB ear irradiation. Furthermore, the melanocyte activity suppression effect was stronger in female mice than in male mice. Following the administration of tranexamic acid, the female displayed increased blood levels of β-endorphin and μ-opioid receptor and estradiol receptor β expression in comparison with the male. Furthermore, the effect of melanocyte activity suppression in the female mice was decreased by the administration of tamoxifen (antagonist of estrogen receptor) or naltrexone (antagonist of μ-opioid receptor). These results suggest that the suppression by tranexamic acid of the UVB-induced melanocyte activation (UVB sensitivity) is stronger in female mice than in male mice and that female hormones and β-endorphin play an important role in this sex difference. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Protection of human keratinocytes from UVB-induced inflammation using root extract of Lithospermum erythrorhizon.

PubMed

Ishida, Takahiro; Sakaguchi, Ikuyo

2007-05-01

UVB irradiation is an important inducer of biological changes in skin and can activate inflammatory reactions and apoptotic pathways, leading to skin damage. A root extract of Lithospermum erythrorhizon (SK), which has naphthoquinone pigments containing shikonin and shikonin derivatives, is known for its anti-inflammatory, anti-bacterial, and anti-tumor activity, and for its scavenging of reactive oxygen species. However, the effect of SK against UV damage is not clear. The aim of this study was to evaluate the efficacy of SK against UVB induced damage in normal human epidermal keratinocytes (NHEK). UVB-irradiated NHEK showed decreased cell viability, increased production of interleukin (IL)-1alpha, IL-6, IL-8, and tumor necrosis factor-alpha, and induced apoptosis. In an apoptosis pathway assay, UVB-irradiated NHEK showed increased caspase-3 activity, p53 and its phosphorylation at serine 15 compared with non-irradiated cells. All these effects induced by UVB irradiation were clearly inhibited by treatment with SK before and after UVB irradiation for 24 h. It is suggested that SK can protect epidermal cells against harmful effects of UVB irradiation and that SK treatment is probably beneficial for photoprotection of the skin.

[Effect of flavin adenine dinucleotide on ultraviolet B induced damage in cultured human corneal epithelial cells].

PubMed

Sakamoto, Asuka; Nakamura, Masatsugu

2012-01-01

This study evaluated the effects of flavin adenine dinucleotide (FAD) on ultraviolet B (UV-B)-induced damage in cultured human corneal epithelial (HCE-T) cells. The cultured HCE-T cells were treated with 0.003125-0.05% FAD before exposure to 80 mJ/cm2 UV-B. Cell viability was measured 24 h after UV-B irradiation using the MTS assay. Reactive oxygen species (ROS) were detected 30 min after UV-B irradiation using 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate acetyl ester. Apoptosis was evaluated 4 h after UV-B irradiation in the caspase-3/7 activity assay. UV-B irradiation reduced cell viability and stimulated ROS production and caspase-3/7 activity in HCE-T cells. Pretreatment of UV-B irradiated HCE-T cells with FAD significantly attenuated cell viability reduction and inhibited the stimulation of both ROS production and caspase-3/7 activity due to UV-B exposure compared with those with vehicle (0% FAD). These results clarified that FAD inhibits ROS-mediated apoptosis by UV-B irradiation in HCE-T cells and suggest that FAD may be effective as a radical scavenger in UV-B-induced corneal damage.

Silver nanoparticles protect human keratinocytes against UVB radiation-induced DNA damage and apoptosis: potential for prevention of skin carcinogenesis

PubMed Central

Arora, Sumit; Tyagi, Nikhil; Bhardwaj, Arun; Rusu, Lilia; Palanki, Rohan; Vig, Komal; Singh, Shree R.; Singh, Ajay P.; Palanki, Srinivas; Miller, Michael E.; Carter, James E.; Singh, Seema

2015-01-01

Ultraviolet (UV)-B radiation from the sun is an established etiological cause of skin cancer, which afflicts more than a million lives each year in the United States alone. Here, we tested the chemopreventive efficacy of silver-nanoparticles (AgNPs) against UVB-irradiation-induced DNA damage and apoptosis in human immortalized keratinocytes (HaCaT). AgNPs were synthesized by reduction-chemistry and characterized for their physicochemical properties. AgNPs were well tolerated by HaCaT cells and their pretreatment protected them from UVB-irradiation-induced apoptosis along with significant reduction in cyclobutane-pyrimidine-dimer formation. Moreover, AgNPs pre-treatment led to G1-phase cell-cycle arrest in UVB-irradiated HaCaT cells. AgNPs were efficiently internalized in UVB-irradiated cells and localized into cytoplasmic and nuclear compartments. Furthermore, we observed an altered expression of various genes involved in cell-cycle, apoptosis and nucleotide-excision repair in HaCaT cells treated with AgNPs prior to UVB-irradiation. Together, these findings provide support for potential utility of AgNPs as novel chemopreventive agents against UVB-irradiation-induced skin carcinogenesis. PMID:25804413

Bilirubin levels and phototherapy use before and after neonatal red blood cell transfusions.

PubMed

Carroll, Patrick D; Christensen, Robert D; Baer, Vickie L; Sheffield, Mark J; Gerday, Erick; Ilstrup, Sarah J

2016-11-01

Our previous retrospective study suggested that red blood cell (RBC) transfusion of preterm neonates can be associated with an increase in bilirubin, but this has not been tested prospectively. We studied neonates before and after RBC transfusions, recording serial bilirubin levels and whether they qualified for phototherapy. Because lysed RBCs release plasma-free hemoglobin (Hb), a precursor to bilirubin, we also measured plasma free Hb and bilirubin from the donor blood. We studied 50 transfusions given to 39 neonates. Gestation ages of transfused neonates, at birth, were 26 (24-29) weeks (median [interquartile range]); birthweights were 750 (620-1070) g. The study transfusion was given on Day of Life 9.9 (3.4-19.2). In 20% (10/50) phototherapy was being administered at the beginning of and during the transfusion. In these patients neither the 4- to 6- nor the 24- to 36-hour-posttransfusion bilirubin levels were significantly higher than before transfusion. However, in 30% of the others (12/40) phototherapy was started (or restarted) after the transfusion and 15% had a posttransfusion bilirubin increase of at least 2.5 mg/dL. These neonates received donor blood with a higher plasma-free Hb (p < 0.05). Neonates commonly qualify for phototherapy after transfusion. A minority (15% in this series) have a posttransfusion bilirubin increase of at least 2.5 mg/dL. We speculate that neonates qualifying for a RBC transfusion, who are judged to be at high risk for bilirubin-induced neurotoxicity, might benefit from checking their serum bilirubin level after the transfusion and providing donor blood with low plasma-free Hb levels. © 2016 AABB.

Assessment of the influence of Laser phototherapy on the bone repair process of complete fractures in tibiae of rabbits stabilized with semi-rigid internal fixation treated with or without MTA graft: a histological study

NASA Astrophysics Data System (ADS)

Soares, Luiz G. P.; Silva, Aline C. P.; Silva, Anna Paula L. T.; Neves, Bruno Luiz R. C.; Santos, Nicole R. S.; dos Santos, Jean N.; Pinheiro, Antonio L. B.

2016-03-01

Beside biomaterials, Laser phototherapy has shown positive effects as auxiliary therapy in bone repair process, especially when involving large bone losses. The aim of this histological study was to evaluate, by light microscopy, the influence of laser phototherapy on the repair of complete tibial fractures in rabbits treated or not with semi-rigid internal fixation and Mineral Trioxide Aggregate - MTA graft. Twelve Rabbits were randomly divided into four groups with three animals each. After general anesthesia, complete fractures were created in one tibia with a carborundum disk. All animals (groups I-IV) had the fracture stabilized with semi-rigid fixation (wire osteosynthesis - WO). Group I was routinely fixed with WO; groups II and IV fracture was filled by blood clot and MTA implant. In Groups III and IV fracture was filled by blood clot and further irradiated with laser (λ780 nm, 70 mW, CW, Φ = 0.04 cm2, 20.4 J/cm2, per session, t = 300s, 142.8 J/cm2 per treatment). The phototherapy protocol was applied immediately after the surgery and repeated each 48 hours during 15 days. Animal death occurred on the 30th postoperative day. After removal of the specimens, the samples were routinely processed, stained with HE and evaluated by light microscopy. Histologically, the group treated with MTA graft and irradiated with laser showed the fracture filled by a more organized and mature trabecular bone, when compared with all other groups. From the results of the present study, it may be concluded that the association of Laser phototherapy + MTA graft in fractures treated with WO improved bone repair when compared with fractures treated only with WO.

In vitro effect of phototherapy with low-intensity laser on HSV-1 and epithelial cells

NASA Astrophysics Data System (ADS)

Eduardo, Fernanda P.; Mehnert, Dolores U.; Monezi, Telma A.; Zezell, Denise M.; Schubert, Mark M.; Eduardo, Carlos P.; Marques, Márcia M.

2007-02-01

The effects of phototherapy on herpes lesions have been clinically demonstrated by either preventing the lesion formation or speeding their repair. The aim of this in vitro study was analyze the effect of phototherapy on epithelial cells and HSV-1 in culture. Cultures of HSV-1 and epithelial cells (Vero cell line) were used. The irradiations were done using a GaAlAs laser (660 e 780 nm, 4.0 mm2). One, two and three irradiations with 6 h-intervals were done. The experimental groups were: Control: non-irradiated; 660 nm and 3 J/cm2 (2.8 sec); 660 nm and 5 J/cm2 (3.8 sec); 780 nm and 3 J/cm2 (1.9 sec), and 780 nm and 5 J/cm2 (2.5 sec). The HSV-1 cytopatic effect and the cell viability of irradiated cultures and controls were analyzed in four different conditions: irradiation of non-infected epithelial cells; epithelial cells irradiated prior infection; virus irradiated prior infection; irradiation of HSV infected cells. The mitochondrial activity and cytopathic effects were assessed. The number of irradiations influenced the cell growth positively and proportionally, except for the 660 nm/ 3 J/cm2 group. Any variation in cytopathic effects was observed amongst the experimental groups. The viability of infected cells prior irradiation was significantly higher than that of non-irradiated cultures when 2 irradiations were done. Under the experimental conditions of this study we concluded that phototherapy is capable of enhancing epithelial cell growth and prolonging cell viability of HSV-1 infected cells. Positive benefits of phototherapy could be resultant from prolongation of infected cells viability, corroborating with host defenses.

Probiotics for the management of neonatal hyperbilirubinemia: a systematic review of randomized controlled trials.

PubMed

Deshmukh, Janki; Deshmukh, Mangesh; Patole, Sanjay

2017-08-31

Neonatal jaundice requiring phototherapy is associated with significant socioeconomic burden including hospital readmission, prolonged hospital stay, and separation of the baby from mother. To assess the efficacy and safety of probiotics in reducing the need for phototherapy and its duration in neonatal hyperbilirubinemia. A systematic review of randomized controlled trials (RCTs) of probiotic supplementation for prevention or treatment of jaundice in neonates (any gestation or weight) using the Cochrane methodology. Primary outcome was the duration of phototherapy. Secondary outcomes included incidence of jaundice, total serum bilirubin (TSB) level at 24, 48, 72, 96 h, and day 7, duration of hospital stay, and adverse effects (e.g. probiotic sepsis). Results were summarized as per GRADE guidelines. Nine RCTs (prophylactic: six trials, N = 1761; therapeutic: three trials, N = 279) with low to high risk of bias were included. Meta-analysis (random-effects model) showed probiotic supplementation reduced duration of phototherapy [N = 415, mean difference (MD): -11.80 (-17.47, -6.13); p < .0001; level of evidence (LOE): low]. TSB was significantly reduced at 96 h [MD: -1.74 (-2.92, -0.57); p = .004] and 7 d [MD: -1.71 (-2.25, -1.17); p < .00001; LOE: low] after probiotic treatment. Prophylactic probiotics did not reduce the incidence of jaundice significantly [N = 1582, relative risk (RR): 0.56 (0.25, 1.27); p = .16; LOE: low]. There were no probiotic-related adverse effects. Limited low-quality evidence indicates that probiotic supplementation may reduce the duration of phototherapy in neonates with jaundice. Routine use of probiotics to prevent or treat neonatal jaundice cannot be recommended. Large well-designed trials are essential to confirm these findings.

Baicalin Scavenged Reactive Oxygen Species and Protected Human Keratinocytes Against UVB-induced Cytotoxicity.

PubMed

Chang, Wen-Shin; Lin, En-Yuan; Hsu, Shih-Wei; Hu, Pei-Shin; Chuang, Chin-Liang; Liao, Cheng-Hsi; Fu, Chun-Kai; Su, Chung-Hao; Gong, Chi-Li; Hsiao, Chieh-Lun; Bau, DA-Tian; Tsai, Chia-Wen

Ultraviolet B (UVB), with a wavelength of 280-320 nm, represents one of the most important environmental factors for skin disorders, including sunburn, hyperpigmentation, solar keratosis, solar elastosis and skin cancer. Therefore, protection against excessive UVA-induced damage is useful for prevention of sunburn and other human diseases. Baicalin, a major component of traditional Chinese medicine Scutellaria baicalensis, has been reported to possess antioxidant and cytostatic capacities. In this study, we examined whether baicalin is also capable of protecting human keratinocytes from UVB irradiation. The results showed that baicalin effectively scavenged reactive oxygen species (ROS) elevated within 4 h after UVB radiation and reversed the UVB-suppressed cell viability and UVB-induced apoptosis after 24 h. Our results demonstrated the utility of baicalin to complement the contributions of traditional Chinese medicine in UVB-induced damage to skin and suggested their potential application as pharmaceutical agents in long-term sun-shining injury prevention. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

UV-B measurements in India

NASA Astrophysics Data System (ADS)

Prasad, B. S. N.; Gayathri, H. B.; Muralikrishnan, N.

1992-01-01

Global UV-B flux (sum of direct and diffuse radiations) data at four wavelengths 280, 290, 300 and 310 nm are recorded at several locations in India as part of Indian Middle Atmosphere Programme (IMAP). The stations have been selected considering distinct geographic features and possible influence of atmospheric aerosols and particulates on the ground reaching UV-B flux. Mysore (12.6°N, 76.6°E) has been selected as a continental station largely free from any industrial pollution and large scale bio-mass burning. An examination of the ground reaching UV-B flux at Mysore shows a marked dirunal and seasonal asymmetry. This can be attributed to the seasonally varying atmospheric aerosols and particulates which influence the scattering of UV-B radiation. The available parameterization models are used to reproduce the experimental UV-B irradiance by varying the input parameters to the model. These results on the dirunal and seasonal variation of global UV-B flux from experiment and models are discussed in this paper.

UVR2 ensures transgenerational genome stability under simulated natural UV-B in Arabidopsis thaliana

PubMed Central

Willing, Eva-Maria; Piofczyk, Thomas; Albert, Andreas; Winkler, J. Barbro; Schneeberger, Korbinian; Pecinka, Ales

2016-01-01

Ground levels of solar UV-B radiation induce DNA damage. Sessile phototrophic organisms such as vascular plants are recurrently exposed to sunlight and require UV-B photoreception, flavonols shielding, direct reversal of pyrimidine dimers and nucleotide excision repair for resistance against UV-B radiation. However, the frequency of UV-B-induced mutations is unknown in plants. Here we quantify the amount and types of mutations in the offspring of Arabidopsis thaliana wild-type and UV-B-hypersensitive mutants exposed to simulated natural UV-B over their entire life cycle. We show that reversal of pyrimidine dimers by UVR2 photolyase is the major mechanism required for sustaining plant genome stability across generations under UV-B. In addition to widespread somatic expression, germline-specific UVR2 activity occurs during late flower development, and is important for ensuring low mutation rates in male and female cell lineages. This allows plants to maintain genome integrity in the germline despite exposure to UV-B. PMID:27905394

Effects of Increased UVB radiation on plant-insect interactions: Plantago lanceolata and Junonia coenia

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCloud, E.S.; Berenbaum, M.R.

Seeds of P. lanceolata were collected from a local population and 4 replicates of 42 maternal families were grown for 90 days in the greenhouse with at two levels of supplemental UVB radiation (6 and 12 kJ day[sup [minus]1] BE[sub 300]). Higher UVB radiation increased leaf hair density and decreased plant size during early growth; family identity affected these also. Leaves excised from a subset of the plants were fed to ultimate instar larvae of J. coenia and assayed for iridoids. Increased UVB radiation did not alter the iridoid content of the leaves or the growth of the larvae. Inmore » a separate experiment, P. lanceolata growing under the two levels of UVB irradiation were infested with neonate larvae and larval growth was monitored. Larval growth was not markedly altered by enhanced UVB. These findings suggest that increased UVB is unlikely to alter the suitability of P. lanceolata as a host for J. coenia.« less

Comparative sensitivity to UV-B radiation of two Bacillus thuringiensis subspecies and other Bacillus sp.

PubMed

Myasnik, M; Manasherob, R; Ben-Dov, E; Zaritsky, A; Margalith, Y; Barak, Z

2001-08-01

Susceptibility of Bacillus thuringiensis spores and toxins to the UV-B range (280--330 nm) of the solar spectrum reaching Earth's surface may be responsible for its inactivation and low persistence in nature. Spores of the mosquito larvicidal B. thuringiensis subsp. israelensis were significantly more resistant to UV-B than spores of the lepidopteran-active subsp. kurstaki. Spores of subsp. israelensis were as resistant to UV-B as spores of B. subtilis and more resistant than spores of the closely related B. cereus and another mosquito larvicidal species B. sphaericus. Sensitivity of B. thuringiensis subsp. israelensis spores to UV-B radiation depended upon their culture age; 24-h cultures, approaching maximal larvicidal activity, were still sensitive. Maximal resistance to UV-B was achieved only at 48 h.

Spot fat reduction by red and near infrared LED phototherapy

NASA Astrophysics Data System (ADS)

Lim, Sungkyoo; Park, Eal-Whan

2018-02-01

Low level light therapy (LLLT) using light from red and near infrared LEDs or Lasers have been reported effective as noninvasive methods for reducing spot fat. A total of 55 subjects were randomly divided into test groups and control groups for abdominal fat reduction clinical trial using red and near infrared LED phototherapy devices. Red and near infrared light with irradiance of 10 mW/cm2 were irradiated over the abdominal area to the test group for 30 minutes followed by 30 minutes of aerobic exercise, 3 times a week for 4 weeks. Control group used sham devices for 30 minutes and followed by 30 minutes of aerobic exercise. It is expected that red and near infrared LED phototherapy combined with aerobic exercise would be effective and safe for abdominal fat reduction without any side effects.

UV-B photoreceptor-mediated signalling in plants.

PubMed

Heijde, Marc; Ulm, Roman

2012-04-01

Ultraviolet-B radiation (UV-B) is a key environmental signal that is specifically perceived by plants to promote UV acclimation and survival in sunlight. Whereas the plant photoreceptors for visible light are rather well characterised, the UV-B photoreceptor UVR8 was only recently described at the molecular level. Here, we review the current understanding of the UVR8 photoreceptor-mediated pathway in the context of UV-B perception mechanism, early signalling components and physiological responses. We further outline the commonalities in UV-B and visible light signalling as well as highlight differences between these pathways. Copyright © 2012 Elsevier Ltd. All rights reserved.

Influence of clouds on UV-B penetration to the earth's surface

NASA Technical Reports Server (NTRS)

Green, A. E. S.

1979-01-01

Radiometric measurements of cloud influence on ultraviolet B radiation (UV-B) were obtained. Mathematical models of the influence were defined to lay the groundwork for the construction of the global UV-B climatology from satellite determined ozone data. More refined measurements comparing UV-B radiation with total solar radiation were carried out. The cloudy case is referred to the cloudless sky irradiance and convenient transmission ratios are given An approach to the inversion of scattering data is summarized. An improved characterization of the UV-B radiation from a cloudless sky is also presented.

Impacts of long-term enhanced UV-B radiation on bryophytes in two sub-Arctic heathland sites of contrasting water availability.

PubMed

Arróniz-Crespo, M; Gwynn-Jones, D; Callaghan, T V; Núñez-Olivera, E; Martínez-Abaigar, J; Horton, P; Phoenix, G K

2011-09-01

Anthropogenic depletion of stratospheric ozone in Arctic latitudes has resulted in an increase of ultraviolet-B radiation (UV-B) reaching the biosphere. UV-B exposure is known to reduce above-ground biomass and plant height, to increase DNA damage and cause accumulation of UV-absorbing compounds in polar plants. However, many studies on Arctic mosses tended to be inconclusive. The importance of different water availability in influencing UV-B impacts on lower plants in the Arctic has been poorly explored and might partially explain the observed wide variation of responses, given the importance of water in controlling bryophyte physiology. This study aimed to assess the long-term responses of three common sub-Arctic bryophytes to enhanced UV-B radiation (+UV-B) and to elucidate the influence of water supply on those responses. Responses of three sub-Arctic bryophytes (the mosses Hylocomium splendens and Polytrichum commune and the liverwort Barbilophozia lycopodioides) to +UV-B for 15 and 13 years were studied in two field experiments using lamps for UV-B enhancement with identical design and located in neighbouring areas with contrasting water availability (naturally mesic and drier sites). Responses evaluated included bryophyte abundance, growth, sporophyte production and sclerophylly; cellular protection by accumulation of UV-absorbing compounds, β-carotene, xanthophylls and development of non-photochemical quenching (NPQ); and impacts on photosynthesis performance by maximum quantum yield (F(v) /F(m)) and electron transport rate (ETR) through photosystem II (PSII) and chlorophyll concentrations. Responses were species specific: H. splendens responded most to +UV-B, with reduction in both annual growth (-22 %) and sporophyte production (-44 %), together with increased β-carotene, violaxanthin, total chlorophyll and NPQ, and decreased zeaxanthin and de-epoxidation of the xanthophyll cycle pool (DES). Barbilophozia lycopodioides responded less to +UV-B, showing increased β-carotene and sclerophylly and decreased UV-absorbing compounds. Polytrichum commune only showed small morphogenetic changes. No effect of UV-B on bryophyte cover was observed. Water availability had profound effects on bryophyte ecophysiology, and plants showed, in general, lower growth and ETR, together with a higher photoprotection in the drier site. Water availability also influenced bryophyte responses to +UV-B and, in particular, responses were less detectable in the drier site. Impacts of UV-B exposure on Arctic bryophytes were significant, in contrast to modest or absent UV-B effects measured in previous studies. The impacts were more easily detectable in species with high plasticity such as H. splendens and less obvious, or more subtle, under drier conditions. Species biology and water supply greatly influences the impact of UV-B on at least some Arctic bryophytes and could contribute to the wide variation of responses observed previously.

Resveratrol-Enriched Rice Down-Regulates Melanin Synthesis in UVB-Induced Guinea Pigs Epidermal Skin Tissue

PubMed Central

Lee, Taek Hwan; Seo, Jae Ok; Do, Moon Ho; Ji, Eunhee; Baek, So-Hyeon; Kim, Sun Yeou

2014-01-01

Synthetic compounds that are used in the clinic to regulate skin hyperpigmentation, such as arbutin, hydroquinone, and kojic acid, are only moderately effective. But, their use is limited by side effects. As part of an effort to overcome the limitations, we developed resveratrol-enriched rice (RR) using genetic engineering technique. Each of resveratrol and rice has been reported to produce anti-melanogenic effects. Therefore, we hypothesized that RR would show more anti-melanogenic effects than those of resveratrol or rice alone. Anti-melanogenic effect of RR was done by using melan-a mouse melanocytes. The depigmenting efficacy was then observed following topical application of the RR to UVB-stimulated hyperpigmented dorsal skin of guinea pigs. Treatment with RR extract resulted a 21.4 ± 0.7% decrease in tyrosinase expression at melan-a cells. Colorimetric analysis showed a significantly lower depigmenting value by day 9 following treatment with RR in UVB-irradiated guinea pigs the dorsal skin (p<0.01), indicating that RR produced a depigmentation effect. By staining with Fontana-Masson stain, we found that the RR-treated group had more effect histopathologically in epidermal melanin production than resveratrol or rice alone-treated group. RR was associated with reduction in the levels of microphthalmia-associated transcription factor (MITF), and downregulation of tyrosinase and tyrosinase-related protein (TRP-2) expression, leading to inhibit epidermal melanin production by western blot analysis. This study suggests that the resveratrol-enriched rice may be a promising candidate in regulating skin pigmentation with UVB exposure. PMID:25414774

Risk Assessment of Face Skin Exposure to UV Irradiance from Different Rotation Angle Ranges.

PubMed

Wang, Fang; Gao, Qian; Deng, Yan; Chen, Rentong; Liu, Yang

2017-06-06

Ultraviolet (UV) is one of the environmental pathogenic factors causing skin damage. Aiming to assess the risk of face skin exposure to UV irradiance from different rotation angles, a rotating model was used to monitor the exposure of the skin on the face to UV irradiance, with skin damage action spectra used to determine the biologically effective UV irradiance (UVBE skin ) and UVBE skin radiant exposure (HBE skin ) causing skin damage. The results indicate that the UVBE skin is directly influenced by variations in rotation angles. A significant decrease of approximately 52.70% and 52.10% in UVBE skin was found when the cheek and nose measurement sites was rotated from 0° to 90°, while a decrease of approximately 62.70% was shown when the forehead measurement sites was rotated from an angle of 0° to 108°. When HBE skin was compared to the exposure limits (ELs; 30 J·m -2 ), the maximum relative risk ratios (RR) for cheek, nose, and forehead were found to be approximately 2.01, 2.40, and 2.90, respectively, which were all measured at a rotation angle of 0°. The maximal increase in the percentage of the average HBE skin for rotation angles of 60°, 120°, 180°, and 360° facing the sun to ELs were found to be approximately 62.10%, 52.72%, 43.43%, and 26.27% for the cheek; approximately 130.61%, 109.68%, 86.43%, and 50.06% for the nose; and approximately 178.61%, 159.19%, 134.38%, and 83.41% for the forehead, respectively.

The angular distributions of ultraviolet spectral irradiance at different solar elevation angles under clear sky conditions

NASA Astrophysics Data System (ADS)

Liu, Yan; Hu, LiWen; Wang, Fang; Gao, YanYan; Zheng, Yang; Wang, Yu; Liu, Yang

2016-01-01

To investigate the angular distributions of UVA, UVB, and effective UV for erythema and vitamin D (vitD) synthesis, the UV spectral irradiances were measured at ten inclined angles (from 0° to 90°) and seven azimuths (from 0° to 180°) at solar elevation angle (SEA) that ranged from 18.8° to 80° in Shanghai (31.22° N, 121.55° E) under clear sky and the albedo of ground was 0.1. The results demonstrated that in the mean azimuths and with the back to the sun, the UVA, UVB, and erythemally and vitD-weighted irradiances increased with the inclined angles and an increase in SEA. When facing toward the sun at 0°-60° inclined angles, the UVA first increased and then decreased with an increase in SEA; at other inclined angles, the UVA increased with SEA. At 0°-40° inclined angles, the UVB and erythemally and vitD-weighted irradiances first increased and then decreased with an increase in SEA, and their maximums were achieved at SEA 68.7°; at other inclined angles, the above three irradiances increased with an increase in SEA. The maximum UVA, UVB, and erythemally and vitD-weighted irradiances were achieved at an 80° inclined angle at SEA 80° (the highest in our measurements); the cumulative exposure of the half day achieved the maximum at a 60° inclined angle, but not on the horizontal. This study provides support for the assessment of human skin sun exposure.

Involvement of the Extrinsic and Intrinsic Pathways in Ultraviolet B-Induced Apoptosis of Corneal Epithelial Cells

PubMed Central

Ubels, John L.; Glupker, Courtney D.; Schotanus, Mark P.; Haarsma, Loren D.

2015-01-01

The goal of this study was to elucidate the pathway by which UVB initiates efflux of K+ and subsequently apoptosis in human corneal limbal epithelial (HCLE) cells. The initial focus of the study was on the extrinsic pathway involving Fas. HCLE cells transfected with Fas siRNA were exposed to 80–150 mJ/cm2 UVB and incubated in culture medium with 5.5 mM K+. Knock down of Fas resulted in limited reduction in UVB-induced caspase-8 and -3 activity. Patch-clamp recordings showed no difference in UVB-induced normalized K+ currents between Fas transfected and control cells. Knockdown of caspase-8 had no effect on the activation of caspase-3 following UVB exposure, while a caspase-8 inhibitor completely eliminated UVB activation of caspase-3. This suggests that caspase-8 is a robust enzyme, able to activate caspase-3 via residual caspase-8 present after knockdown, and that caspase-8 is directly involved in the UVB activation of caspase-3. Inhibition of caspase-9 significantly decreased the activation of caspases-8 and -3 in response to UVB. Knockdown of Apaf-1, required for activation of caspase-9, resulted in a significant reduction in UVB-induced activation of caspases-9, -8, and -3. Knockdown of Apaf-1 also inhibited intrinsic and UVB-induced levels of apoptosis, as determined by DNA fragmentation measured by TUNEL assay. In UVB exposed cultures treated with caspase-3 inhibitor, the percentage of apoptotic cells was reduced to control levels, confirming the necessity of caspase-3 activation in DNA fragmentation. The lack of effect of Fas knockdown on K+ channel activation, as well as the limited effect on activation of caspases-8 and -3, strongly suggest that Fas and the extrinsic pathway is not of primary importance in the initiation of apoptosis in response to UVB in HCLE cells. Inhibition of caspase-8 and -3 activation following inhibition of caspase-9, as well as reduction in activation of caspases-9, -8, and -3 and DNA fragmentation in response to Apaf-1 knockdown support the conclusion that the intrinsic pathway is more important in UVB-induced apoptosis in HCLE cells. PMID:26559338

[Effects of silicon supply on diurnal variations of physiological properties at rice heading stage under elevated UV-B radiation].

PubMed

Wu, Lei; Lou, Yun-sheng; Meng, Yan; Wang, Wei-qing; Cui, He-yang

2015-01-01

A pot experiment was conducted to investigate the effects of silicon (Si) supply on diurnal variations of photosynthesis and transpiration-related physiological parameters at rice heading stage under elevated UV-B radiation. The experiment was designed with two UV-B radiation levels, i.e. ambient UV-B. (ambient, A) and elevated UV-B (elevated by 20%, E), and four Si supply levels, i.e. Sio (control, 0 kg SiO2 . hm-2), Si, (sodium silicate, 100 kg SiO2 . hm-2), Si2 (sodium silicate, 200 kg SiO2 . hm2), Si3 (slag fertilizer, 200 kg SiO2 . hm-2). The results showed that, compared with ambient UV-B radiation, elevated UV-B radiation decreased the net photosynthesis rate (Pn) , intercellular CO2 concentration (Ci), transpiration rate (Tr), stomatal conductivity (gs) and water use efficiency (WUE) by 11.3%, 5.5%, 10.4%, 20.3% and 6.3%, respectively, in the treatment without Si supply (Si, level), and decreased the above parameters by 3.8%-5.5%, 0.7%-4.8%, 4.0%-8.7%, 7.4%-20.2% and 0.7%-5.9% in the treatments with Si supply (Si1, Si2 and Si3 levels) , respectively. Namely, elevated UV-B radiation decreased the photosynthesis and transpiration-related physiological parameters, but silicon supply could obviously mitigate the depressive effects of elevated UV-B radiation. Under elevated UV-B radiation, compared with control (Si0 level), silicon supply increased Pn, Ci, gs and WUE by 16.9%-28.0%, 3.5%-14.3%, 16.8% - 38.7% and 29.0% - 51.2%, respectively, but decreased Tr by 1.9% - 10.8% in the treatments with Si supply (Si1 , Si2 and Si3 levels). That is, silicon supply could mitigate the depressive effects of elevated UV-B radiation through significantly increasingnP., CigsgK and WUE, but decreasing T,. However, the difference existed in ameliorating the depressive effects of elevated UV-B radiation on diurnal variations of physiological parameters among the treatments of silicon supply, with the sequence of Si3>Si2>1i >Si0. This study suggested that fertilizing slag was helpful not only in recycling industrial wastes, but also in effectively mitigating the depressive effects of elevated UV-B radiation on photosynthesis and transpiration in rice production.

ROS and calcium signaling mediated pathways involved in stress responses of the marine microalgae Dunaliella salina to enhanced UV-B radiation.

PubMed

Zhang, Xinxin; Tang, Xuexi; Wang, Ming; Zhang, Wei; Zhou, Bin; Wang, You

2017-08-01

UV-B ray has been addressed to trigger common metabolic responses on marine microalgae, however, the upstream events responsible for these changes in marine microalgae are poorly understood. In the present study, a species of marine green microalgae Dunaliella salina was exposed to a series of enhanced UV-B radiation ranging from 0.25 to 1.00 KJ·m -2 per day. The role of ROS and calcium signaling in the D. salina responses to UV-B was discussed. Results showed that enhanced UV-B radiation markedly decreased the cell density in a dose-dependent manner, but the contents of protein and glycerol that were essential for cell growth increased. It suggested that it was cell division instead of cell growth that UV-B exerted negative effects on. The subcellular damages on nuclei and plasmalemma further evidenced the hypothesis. The nutrient absorption was affected with UV-B exposure, and the inhibition on PO 4 3- uptake was more serious compared to NO 3 - uptake. UV-B radiation promoted reactive oxygen species (ROS) formation and thiobarbituric acid reactive substances (TBARS) contents, decreased the redox status and altered the antioxidant enzyme activities. The addition of the ROS scavenger and the glutathione biosynthesis precursor N-acetyl-l-cysteine (NAC) alleviated the stress degree, implying ROS-mediated pathway was involved in the stress response to UV-B radiation. Transient increase in Ca 2+ -ATPase was triggered simultaneously with UV-B exposure. Meanwhile, the addition of an intracellular free calcium chelator aggravated the damage of cell division, but exogenous calcium and ion channel blocker applications did not, inferring that endogenously initiated calcium signaling played roles in response to UV-B. Cross-talk analysis showed a relatively clear relationship between ROS inhibition and Ca 2+ -ATPase suppression, and a relation between Ca 2+ inhibition and GPx activity change was also observed. It was thus presumed that ROS-coupled calcium signaling via the glutathione cycle was involved in the response of marine microalgae to UV-B stimuli. Copyright © 2017 Elsevier B.V. All rights reserved.

Dihydrolipoyl dehydrogenase as a potential UVB target in skin epidermis; using an integrated approach of label-free quantitative proteomics and targeted metabolite analysis.

PubMed

Moon, Eunjung; Park, Hye Min; Lee, Choong Hwan; Do, Seon-Gil; Park, Jong-Moon; Han, Na-Young; Do, Moon Ho; Lee, Jong Ha; Lee, Hookeun; Kim, Sun Yeou

2015-03-18

Photodamage is extrinsically induced by overexposure to ultraviolet (UV) radiation, and it increases the risk of various skin disorders. Therefore, discovery of novel biomarkers of photodamage is important. In this study, using LC-MS/MS analysis of epidermis from UVB-irradiated hairless mice, we identified 57 proteins whose levels changed after UVB exposure, and selected 7 proteins related to the tricarboxylic acid (TCA) cycle through pathway analysis. Dihydrolipoyl dehydrogenase (DLD) was the only TCA cycle-associated protein that showed a decreased expression after the UVB exposure. We also performed targeted analysis to detect intermediates and products of the TCA cycle using GC-TOF-MS. Interestingly, malic acid and fumaric acid levels significantly decreased in the UVB-treated group. Our results demonstrate that DLD and its associated metabolites, malic acid and fumaric acid, may be candidate biomarkers of UVB-induced skin photoaging. Additionally, we showed that Aloe vera, a natural skin moisturizer, regulated DLD, malic acid and fumaric acid levels in UVB-exposed epidermis. Our strategy to integrate the proteome and targeted metabolite to detect novel UVB targets will lead to a better understanding of skin photoaging and photodamage. Our study also supports that A. vera exerts significant anti-photodamage activity via regulation of DLD, a novel UVB target, in the epidermis. This study is the first example of an integration of proteomic and metabolite analysis techniques to find new biomarker candidates for the regulation of the UVB-induced skin photoaging. DLD, malic acid, and fumaric acid can be used for development of cosmeceuticals and nutraceuticals regulating the change of skin metabolism induced by the UVB overexposure. Moreover, this is also the first attempt to investigate the role of the TCA cycle in photodamaged epidermis. Our integration of the proteomic and targeted metabolite analyses will lead to a better understanding of the unidentified photobiological results from UVB-irradiated models and can elicit new diagnostic and treatment strategies based on altered metabolism. Copyright © 2015. Published by Elsevier B.V.

Studies on the mechanism of photodynamic-therapy-induced tumor destruction

NASA Astrophysics Data System (ADS)

Fingar, Victor H.; Wieman, Thomas J.

1990-07-01

There exists little doubt that profound changes occur to both tumor and normal tissue microvasculature during photodynamic therapy, and that these changes are important in the process of tumor destruction. We hypothesize that singlet oxygen, produced during light activation of photosensitizer, interacts with cellular membranes and induces the release of arachidonic acid metabolites, notably thromboxane, into the intravascular environment. This leads to vasoconstriction, platelet aggregation, and hemostasis. To test this hypothesis, we have measured the release of thromboxane into serum as a function of porphyrin and light doses used in phototherapy. Sprague Dawley rats bearing chondrosarcoma in the right hind limb were injected with 0-25 mg/kg Photofrin IP'. A catheter was implanted in the carotid artery 24 h later, and the hind limb exposed to 0-135 J/cm2 630 nm light. Immediately after treatment, serum was collected and thromboxane levels were measured by radioimmunoassay. We found significant increases in systemic thromboxane concentrations following phototherapy at the highest porphyrin and light doses, compared to drug and light controls. The administration of indomethacin (10 mg/kg i.p.) prior to treatment suppressed the release of thromboxane from tumor and normal tissues and inhibited hemostasis and tumor response to phototherapy. These studies have reinforced the important role of arachidonic acid metabolites in producing vascular damage during phototherapy.

Effects of phototherapy on cartilage structure and inflammatory markers in an experimental model of osteoarthritis

NASA Astrophysics Data System (ADS)

Oliveira, Poliani; Santos, Anderson Amaro; Rodrigues, Tamara; Tim, Carla Roberta; Pinto, Karina Zambone; Magri, Angela Maria Paiva; Fernandes, Kelly Rossetti; Mattiello, Stela M.; Parizotto, Nivaldo Antonio; Anibal, Fernanda Freitas; Rennó, Ana Claudia Muniz

2013-12-01

The aim of this study was to evaluate the effects of laser phototherapy on the degenerative modifications on the articular cartilage after the anterior cruciate ligament transection (ACLT) in the knee of rats. Eighty male rats (Wistar) were distributed into four groups: intact control group (IG), injured control group (CG), injured laser treated group at 10 J/cm2 (L10), and injured laser treated group at 50 J/cm2 (L50). Animals were distributed into two subgroups, sacrificed in 5 and 8 weeks postsurgery. The ACLT was used to induce knee osteoarthritis in rats. After 2 weeks postsurgery, laser phototherapy initiated and it was performed for 15 and 30 sessions. The histological findings revealed that laser irradiation, especially at 10 J/cm2, modulated the progression of the degenerative process, showing a better cartilage structure and lower number of condrocytes compared to the other groups. Laser phototherapy was not able to decrease the degenerative process measured by Mankin score and prevent the increase of cartilage thickness related to the degenerative process. Moreover, it did not have any effect in the biomodulation of the expression of markers IL1β, tumor necrosis factor-α, and metalloprotein-13. Furthermore, laser irradiated animals, at 50 J/cm2 showed a lower amount of collagen type 1.

[Treatment with the use of microcurrent lymphatic drainage physiotherapy during the postoperative period following rhinoplastic surgery].

PubMed

Aleksanyan, T A; Kazantsev, E V

The objective of the present study was to evaluate the effectiveness of the combined treatment of the patients who had undergone either primary or secondary rhinoplastic surgery with the use of photo- and magnetic therapy in comparison with the effectiveness of phototherapy in the combination with microcurrent therapy. The patients were divided into four groups depending on the type of the surgical intervention and the mode of the combined physiotherapeutic treatment. All the patients were given combined physiotherapeutic treatment in addition to the standard pharmacotherapy starting from the second day of the postoperative period. The patients of groups 1 and 3 received phototherapy in the combination with magnetic therapy while those in groups 2 and 4 were treated by phototherapy in the combination with microcurrent lymphatic drainage physiotherapy. It was shown that the different combinations of physiotherapeutic modalities during the postoperative period following primary «closed» rhinoplasty were not different significantly in terms of effectiveness. After secondary «closed» rhinoplasty, the combination of phototherapy with the application of microcurrents looks more preferable. It is concluded that microcurrent lymphdraining physiotherapy should be regarded as the priority component of the combined physiotherapeutic treatment during the postoperative period following secondary «closed» rhinoplasty.

Phthalocyanine-loaded graphene nanoplatform for imaging-guided combinatorial phototherapy

PubMed Central

Taratula, Olena; Patel, Mehulkumar; Schumann, Canan; Naleway, Michael A; Pang, Addison J; He, Huixin; Taratula, Oleh

2015-01-01

We report a novel cancer-targeted nanomedicine platform for imaging and prospect for future treatment of unresected ovarian cancer tumors by intraoperative multimodal phototherapy. To develop the required theranostic system, novel low-oxygen graphene nanosheets were chemically modified with polypropylenimine dendrimers loaded with phthalocyanine (Pc) as a photosensitizer. Such a molecular design prevents fluorescence quenching of the Pc by graphene nanosheets, providing the possibility of fluorescence imaging. Furthermore, the developed nanoplatform was conjugated with poly(ethylene glycol), to improve biocompatibility, and with luteinizing hormone-releasing hormone (LHRH) peptide, for tumor-targeted delivery. Notably, a low-power near-infrared (NIR) irradiation of single wavelength was used for both heat generation by the graphene nanosheets (photothermal therapy [PTT]) and for reactive oxygen species (ROS)-production by Pc (photodynamic therapy [PDT]). The combinatorial phototherapy resulted in an enhanced destruction of ovarian cancer cells, with a killing efficacy of 90%–95% at low Pc and low-oxygen graphene dosages, presumably conferring cytotoxicity to the synergistic effects of generated ROS and mild hyperthermia. An animal study confirmed that Pc loaded into the nanoplatform can be employed as a NIR fluorescence agent for imaging-guided drug delivery. Hence, the newly developed Pc-graphene nanoplatform has the significant potential as an effective NIR theranostic probe for imaging and combinatorial phototherapy. PMID:25848255

Diurnal changes in CN metabolism and response of rice seedlings to UV-B radiation.

PubMed

Yun, Hyejin; Lim, Sunhyung; Kim, Yangmin X; Lee, Yejin; Lee, Seulbi; Lee, Deogbae; Park, Keewoong; Sung, Jwakyung

2018-03-13

Plants regulate a number of primary metabolites, including carbohydrates, organic acids, and amino acids, in response to UV-B radiation. Therefore, it is essential to understand the time-dependent response of rice plants to UV-B stress. This study focused on the response of plants to UV-B at different leaf developmental phases (emerging, growing, and maturing) in an attempt to fully comprehend the metabolic shift. We analyzed the expression levels of genes related to starch/sucrose metabolism in the leaf blades of rice seedlings (Oryza sativa L. "Saechuchenog") exposed to UV-B irradiation for short (1 day) and long terms (5 days) using quantitative real-time polymerase chain reaction. We also examined the diurnal variations in the contents of primary metabolites using an established GCTOF-MS (gas chromatography time of flight-mass spectrometry) method. The results showed that the levels of primary metabolites were largely dependent upon the diurnal rhythm and leaf developmental phase. The young leaves (sink) produced and accumulated starch rather than sucrose. The short-term (4 h, 1 day) UV-B exposure inhibited sucrose synthesis, which could be the first target of UV-B radiation. Following short- and long-term (5 days) exposure to UV-B radiation, the dynamic response of primary metabolites was evaluated. It was found that the content of carbohydrates decreased throughout the period of exposure to UV-B stress, especially in terms of sucrose concentration. However, the content of the majority of amino acids increased after an early decrease. Our data revealed that the metabolic response, as well as the gene expression, differed with the period (intensity) of exposure to UV-B radiation and with the phase of leaf development. These findings provide new insights for a better understanding of the metabolic response of a variety of plant species exposed to a wide range of UV-B radiation. Copyright © 2018. Published by Elsevier GmbH.

The Role of p21 in Apoptosis, Proliferation, Cell Cycle Arrest, and Antioxidant Activity in UVB-Irradiated Human HaCaT Keratinocytes

PubMed Central

Chen, Aijun; Huang, Xin; Xue, Zhenan; Cao, Di; Huang, Kun; Chen, Jin; Pan, Yun; Gao, Yongliang

2015-01-01

Background Skin cancer is the most common cancer in the United States, and ultraviolet B (UVB) radiation-induced DNA damage is the major environmental factor underlying skin cancer development. p21, a p53-inducible protein, plays a key role in the cellular response to UVB-induced DNA damage. Material/Methods Through p21 silencing and overexpression, we investigated the role of p21 in apoptosis, proliferation, cell cycle arrest, and oxidative stress in UVB-irradiated HaCaT keratinocytes. Results We found that UVB exposure induced significant p21 downregulation (p<0.05) and was associated with significantly increased apoptosis, significantly decreased proliferation, and significantly increased G2 phase arrest (p<0.05) in UVB-irradiated HaCaT keratinocytes. p21 silencing significantly promoted apoptosis, significantly inhibited G2 phase arrest, and significantly inhibited proliferation (p<0.05), but after UVB irradiation, p21 silencing demonstrated a less significant pro-apoptotic effect and a more significant inhibition of G2 phase arrest (p<0.05), which was reflected in significantly higher proliferative activity (p<0.05). p21 overexpression acted in an anti-apoptotic manner in the absence of UVB-induced DNA damage but acted in a pro-apoptotic manner in the presence of UVB-induced DNA damage, displaying an “antagonistic duality” similar to other growth-promoting oncoproteins. p53 expression mirrored p21 expression, suggesting a regulatory feedback mechanism between p21 and p53 expression. p21 overexpression significantly downregulated glutathione peroxidase and superoxide dismutase antioxidant activity (p<0.05) while significantly upregulating hydrogen peroxide and malondialdehyde content (p<0.05), suggesting a role in decreasing antioxidant defense capabilities in UVB-irradiated HaCaT keratinocytes. Conclusions These findings reveal that p21 may play a key role in HaCaT keratinocytes’ response to UVB exposure. PMID:25925725

UV-B inhibition of hypocotyl growth in etiolated Arabidopsis thaliana seedlings is a consequence of cell cycle arrest initiated by photodimer accumulation

PubMed Central

Biever, Jessica J.; Brinkman, Doug; Gardner, Gary

2014-01-01

Ultraviolet (UV) radiation is an important constituent of sunlight that determines plant morphology and growth. It induces photomorphogenic responses but also causes damage to DNA. Arabidopsis mutants of the endonucleases that function in nucleotide excision repair, xpf-3 and uvr1-1, showed hypersensitivity to UV-B (280–320nm) in terms of inhibition of hypocotyl growth. SOG1 is a transcription factor that functions in the DNA damage signalling response after γ-irradiation. xpf mutants that carry the sog1-1 mutation showed hypocotyl growth inhibition after UV-B irradiation similar to the wild type. A DNA replication inhibitor, hydroxyurea (HU), also inhibited hypocotyl growth in etiolated seedlings, but xpf-3 was not hypersensitive to HU. UV-B irradiation induced accumulation of the G2/M-specific cell cycle reporter construct CYCB1;1-GUS in wild-type Arabidopsis seedlings that was consistent with the expected accumulation of photodimers and coincided with the time course of hypocotyl growth inhibition after UV-B treatment. Etiolated mutants of UVR8, a recently described UV-B photoreceptor gene, irradiated with UV-B showed inhibition of hypocotyl growth that was not different from that of the wild type, but they lacked UV-B-specific expression of chalcone synthase (CHS), as expected from previous reports. CHS expression after UV-B irradiation was not different in xpf-3 compared with the wild type, nor was it altered after HU treatment. These results suggest that hypocotyl growth inhibition by UV-B light in etiolated Arabidopsis seedlings, a photomorphogenic response, is dictated by signals originating from UV-B absorption by DNA that lead to cell cycle arrest. This process occurs distinct from UVR8 and its signalling pathway responsible for CHS induction. PMID:24591052

UV-B induction of the E3 ligase ARIADNE12 depends on CONSTITUTIVELY PHOTOMORPHOGENIC 1

PubMed Central

Xie, Lisi; Lang-Mladek, Christina; Richter, Julia; Nigam, Neha; Hauser, Marie-Theres

2015-01-01

The UV-B inducible ARIADNE12 (ARI12) gene of Arabidopsis thaliana is a member of the RING-between-RING (RBR) family of E3 ubiquitin ligases for which a novel ubiquitination mechanism was identified in mammalian homologs. This RING-HECT hybrid mechanism needs a conserved cysteine which is replaced by serine in ARI12 and might affect the E3 ubiquitin ligase activity. We have shown that under photomorphogenic UV-B, ARI12 is a downstream target of the classical ultraviolet B (UV-B) UV RESISTANCE LOCUS 8 (UVR8) pathway. However, under high fluence rate of UV-B ARI12 was induced independently of UVR8 and the UV-A/blue light and red/far-red photoreceptors. A key component of several light signaling pathways is CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1). Upon UV-B COP1 is trapped in the nucleus through interaction with UVR8 permitting the activation of genes that regulate the biosynthesis of UV-B protective metabolites and growth adaptations. To clarify the role of COP1 in the regulation of ARI12 mRNA expression and ARI12 protein stability, localization and interaction with COP1 was assessed with and without UV-B. We found that COP1 controls ARI12 in white light, low and high fluence rate of UV-B. Furthermore we show that ARI12 is indeed an E3 ubiquitin ligase which is mono-ubiquitinated, a prerequisite for the RING-HECT hybrid mechanism. Finally, genetic analyses with transgenes expressing a genomic pmARI12:ARI12-GFP construct confirm the epistatic interaction between COP1 and ARI12 in growth responses to high fluence rate UV-B. PMID:25817546

Impacts of UVB radiation on food consumption of forest specialist tadpoles.

PubMed

Londero, James Eduardo Lago; Dos Santos, Caroline Peripolli; Segatto, Ana Lúcia Anversa; Passaglia Schuch, André

2017-09-01

Solar ultraviolet radiation B (UVB) is an important environmental stressor for amphibian populations due to its genotoxicity, especially in early developmental stages. Nonetheless, there is an absence of works focused on the UVB effects on tadpoles' food consumption efficiency. In this work, we investigated the effects of the exposure to a low environmental-simulated dose of UVB radiation on food consumption of tadpoles of the forest specialist Hypsiboas curupi [Hylidae, Anura] species. After UVB treatment tadpoles were divided and exposed to a visible light source or kept in the dark, in order to indirectly evaluate the efficiency of DNA repair performed by photolyases and nucleotide excision repair (NER), respectively. The body mass and the amount of food in tadpoles' guts were verified in both conditions and these data were complemented by the micronuclei frequency in blood cells. Furthermore, the keratinized labial tooth rows were analyzed in order to check for possible UVB-induced damage in this structure. Our results clearly show that the body weight decrease induced by UVB radiation occurs due to the reduction of tadpoles' food consumption. This behavior is directly correlated with the genotoxic impact of UVB light, since the micronuclei frequency significantly increased after treatments. Surprisingly, the results indicate that photoreactivation treatment was ineffective to restore the food consumption activity and body weight values, suggesting a low efficiency of photolyases enzymes in this species. In addition, UVB treatments induced a higher number of breaks in the keratinized labial tooth rows, which could be also associated with the decrease of food consumption. This work contributes to better understand the process of weight loss observed in tadpoles exposed to UVB radiation and emphasizes the susceptibility of forest specialist amphibian species to sunlight-induced genotoxicity. Copyright © 2017 Elsevier Inc. All rights reserved.

Lanthanum (III) regulates the nitrogen assimilation in soybean seedlings under ultraviolet-B radiation.

PubMed

Huang, Guangrong; Wang, Lihong; Zhou, Qing

2013-01-01

Ultraviolet-B (UV-B, 280-320 nm) radiation has seriously affected the growth of plants. Finding the technology/method to alleviate the damage of UV-B radiation has become a frontal topic in the field of environmental science. The pretreatment with rare earth elements (REEs) is an effective method, but the regulation mechanism of REEs is unknown. Here, the regulation effects of lanthanum (La(III)) on nitrogen assimilation in soybean seedlings (Glycine max L.) under ultraviolet-B radiation were investigated to elucidate the regulation mechanism of REEs on plants under UV-B radiation. UV-B radiation led to the inhibition in the activities of the key enzymes (nitrate reductase, glutamine synthetase, glutamate synthase) in the nitrogen assimilation, the decrease in the contents of nitrate and soluble proteins, as well as the increase in the content of amino acid in soybean seedlings. The change degree of UV-B radiation at the high level (0.45 W m(-2)) was higher than that of UV-B radiation at the low level (0.15 W m(-2)). The pretreatment with 20 mg L(-1) La(III) could alleviate the effects of UV-B radiation on the activities of nitrate reductase, glutamine synthetase, glutamate synthase, and glutamate dehydrogenase, promoting amino acid conversion and protein synthesis in soybean seedlings. The regulation effect of La(III) under UV-B radiation at the low level was better than that of UV-B radiation at the high level. The results indicated that the pretreatment with 20 mg L(-1) La(III) could alleviate the inhibition of UV-B radiation on nitrogen assimilation in soybean seedlings.

Combined effects of Lanthanum(III) and elevated Ultraviolet-B radiation on root nitrogen nutrient in soybean seedlings.

PubMed

Huang, Guangrong; Wang, Lihong; Sun, Zhaoguo; Li, Xiaodong; Zhou, Qing; Huang, Xiaohua

2015-02-01

Rare earth element pollution and elevated ultraviolet-B (UV-B) radiation occur simultaneously in some regions, but the combined effects of these two factors on plants have not attracted enough attention. Nitrogen nutrient is vital to plant growth. In this study, the combined effects of lanthanum(III) and elevated UV-B radiation on nitrate reduction and ammonia assimilation in soybean (Glycine max L.) roots were investigated. Treatment with 0.08 mmol L(-1) La(III) did not change the effects of elevated UV-B radiation on nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), glutamate synthase (GOGAT), glutamate dehydrogenase (GDH), nitrate, ammonium, amino acids, or soluble protein in the roots. Treatment with 0.24 mmol L(-1) La(III) and elevated UV-B radiation synergistically decreased the NR, NiR, GS, and GOGAT activities as well as the nitrate, amino acid, and soluble protein levels, except for the GDH activity and ammonium content. Combined treatment with 1.20 mmol L(-1) La(III) and elevated UV-B radiation produced severely deleterious effects on all test indices, and these effects were stronger than those induced by La(III) or elevated UV-B radiation treatment alone. Following the withdrawal of La(III) and elevated UV-B radiation, all test indices for the combined treatments with 0.08/0.24 mmol L(-1) La(III) and elevated UV-B radiation recovered to a certain extent, but they could not recover for treatments with 1.20 mmol L(-1) La(III) and elevated UV-B radiation. In summary, combined treatment with La(III) and elevated UV-B radiation seriously affected nitrogen nutrition in soybean roots through the inhibition of nitrate reduction and ammonia assimilation.

Development of a whole-organism model to screen new compounds for sun protection.

PubMed

Wang, Yun-Hsin; Wen, Chi-Chung; Yang, Zhi-Shiang; Cheng, Chien-Chung; Tsai, Jen-Ning; Ku, Chia-Chen; Wu, Hsin-Ju; Chen, Yau-Hung

2009-01-01

We used zebrafish as a whole-organism model to screen new compounds for sun protection activity. First of all, we designed a series of UVB exposure experiments and recorded the phenotypic changes of zebrafish embryos. Results showed that 100 mJ/cm(2) of UVB given six times separated by 30 min intervals is the best condition. Fin malformation (reduced and/or absent fin) phenotypes are the most evident consequences after exposure to UVB. Each fin was affected by UVB, including pelvic, ventral, caudal, and dorsal fin, but pelvic fin seemed to be the most sensitive target after UVB exposure. We furthermore carried out "prevention" and "treatment" experiments using green tea extract and/or (-)-epigallocatechin (EGCG) to test this whole-organism model by observing the morphological changes of all fins (especially pelvic fin) after UVB exposure. Effects of UVB, green tea extract and EGCG on fin development were assessed using the Kaplan-Meier analysis, log-rank test and Cox proportional hazards regression. Results showed that a zebrafish pelvic fin in the UVB + green tea (treatment) group is 5.51 (range from 2.39 to 14.90) times, one in the UVB + green tea (prevention) group is 7.04 (range from 3.11 to 18.92) times, and one in the 25 ppm of EGCG (prevention) group is 22.19 (range from 9.40 to 61.50) times more likely to return to normal fin than one in the UVB only group. On the basis of these observations, we believe this model is effective for screening the higher stability and lower toxicity of new compounds, such as small chemicals which are derivative from EGCG or other dietary agents for sun protection.

Nrf1 CNC-bZIP protein promotes cell survival and nucleotide excision repair through maintaining glutathione homeostasis.

PubMed

Han, Weinong; Ming, Mei; Zhao, Rui; Pi, Jingbo; Wu, Chunli; He, Yu-Ying

2012-05-25

Skin cancer is the most common cancer in the United States. Its major environmental risk factor is UVB radiation in sunlight. In response to UVB damage, epidermal keratinocytes activate a specific repair pathway, i.e. nucleotide excision repair, to remove UVB-induced DNA lesions. However, the regulation of UVB response is not fully understood. Here we show that the long isoform of the nuclear factor erythroid 2-related factor 1 (Nrf1, also called NFE2L1), a cytoprotective transcription factor critical for the expression of multiple antioxidant response element-dependent genes, plays an important role in the response of keratinocytes to UVB. Nrf1 loss sensitized keratinocytes to UVB-induced apoptosis by up-regulating the expression of the proapoptotic Bcl-2 family member Bik through reducing glutathione levels. Knocking down Bik reduced UVB-induced apoptosis in Nrf1-inhibited cells. In UVB-irradiated surviving cells, however, disruption of Nrf1 impaired nucleotide excision repair through suppressing the transcription of xeroderma pigmentosum C (XPC), a factor essential for initiating the global genome nucleotide excision repair by recognizing the DNA lesion and recruiting downstream factors. Nrf1 enhanced XPC expression by increasing glutathione availability but was independent of the transcription repressor of XPC. Adding XPC or glutathione restored the DNA repair capacity in Nrf1-inhibited cells. Finally, we demonstrate that Nrf1 levels are significantly reduced by UVB radiation in mouse skin and are lower in human skin tumors than in normal skin. These results indicate a novel role of Nrf1 in UVB-induced DNA damage repair and suggest Nrf1 as a tumor suppressor in the skin.

7-Hydroxycoumarin prevents UVB-induced activation of NF-κB and subsequent overexpression of matrix metalloproteinases and inflammatory markers in human dermal fibroblast cells.

PubMed

Karthikeyan, Ramasamy; Kanimozhi, Govindasamy; Prasad, Nagarajan Rajendra; Agilan, Balupillai; Ganesan, Muthusamy; Mohana, Shanmugham; Srithar, Gunaseelan

2016-08-01

Ultraviolet B (UVB) irradiation alters multiple molecular pathways in the skin, thereby inducing skin damage. Human dermal fibroblasts (HDFa) were subjected to single UVB-irradiation (18mJ/cm(2)) resulting in reactive oxygen species (ROS) generation, oxidative DNA damage and upregulation of nuclear factor kappa B (NF-κB) expression. Further, it has been observed that there was a significant cytokine production (TNF-α and IL-6) in UVB irradiated HDFa cells. Our results show that 7-hydroxycoumarin (7-OHC) prevents UVB-induced activation of NF-κB thereby subsequently preventing the overexpression of TNF-α and IL-6 in HDFa cells. Further, 7-OHC prevents UVB-induced activation of cyclooxygenase-2 (COX-2) expression, an inflammatory mediator in skin cells. Moreover, 7-OHC inhibited mRNA expression pattern of matrix metalloproteinases (MMP-1 and MMP-9) in UVB irradiated skin cells. Furthermore, 7-OHC restored antioxidant status, thereby scavenging the excessively generated ROS; consequently preventing the oxidative DNA damage. It has also been noticed that 7-OHC prevents UVB mediated DNA damage through activation of DNA repair enzymes such as XRCC1 and HOGG1. In this study, we treated HDFa cells with 7-OHC before and after UVB irradiation and we found that pretreatment showed better results when compared to posttreatment. Further, 7-OHC showed 9.8416 sun protection factor (SPF) value and it absorbs photons in the UVB wavelength rage. Thus, it has been concluded that sunscreen property, free radical scavenging potential and prevention of NF-κB activation play a role for photoprotective property of 7-OHC. Copyright © 2016 Elsevier B.V. All rights reserved.

Enhanced UV-B radiation during pupal stage reduce body mass and fat content, while increasing deformities, mortality and cell death in female adults of solitary bee Osmia bicornis.

PubMed

Wasielewski, Oskar; Wojciechowicz, Tatiana; Giejdasz, Karol; Krishnan, Natraj

2015-08-01

The effects of enhanced UV-B radiation on the oogenesis and morpho-anatomical characteristics of the European solitary red mason bee Osmia bicornis L. (Hymenoptera: Megachilidae) were tested under laboratory conditions. Cocooned females in the pupal stage were exposed directly to different doses (0, 9.24, 12.32, and 24.64 kJ/m(2) /d) of artificial UV-B. Our experiments revealed that enhanced UV-B radiation can reduce body mass and fat body content, cause deformities and increase mortality. Following UV exposure at all 3 different doses, the body mass of bees was all significantly reduced compared to the control, with the highest UV dose causing the largest reduction. Similarly, following UV-B radiation, in treated groups the fat body index decreased and the fat body index was the lowest in the group receiving the highest dose of UV radiation. Mortality and morphological deformities, between untreated and exposed females varied considerably and increased with the dose of UV-B radiation. Morphological deformities were mainly manifested in the wings and mouthparts, and occurred more frequently with an increased dose of UV. Cell death was quantified by the Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay (DNA fragmentation) during early stages of oogenesis of O. bicornis females. The bees, after UV-B exposure exhibited more germarium cells with fragmented DNA. The TUNEL test indicated that in germarium, low doses of UV-B poorly induced the cell death during early development. However, exposure to moderate UV-B dose increased programmed cell death. In females treated with the highest dose of UV-B the vast majority of germarium cells were TUNEL-positive. © 2014 Institute of Zoology, Chinese Academy of Sciences.

BMAL1 and CLOCK proteins in regulating UVB-induced apoptosis and DNA damage responses in human keratinocytes.

PubMed

Sun, Yang; Wang, Peiling; Li, Hongyu; Dai, Jun

2018-06-26

A diverse array of biological processes are under circadian controls. In mouse skin, ultraviolet ray (UVR)-induced apoptosis and DNA damage responses are time-of-day dependent, which are controlled by core clock proteins. This study investigates the roles of clock proteins in regulating UVB responses in human keratinocytes (HKCs). We found that the messenger RNA expression of brain and muscle ARNT-like 1 (BMAL1) and circadian locomotor output cycles kaput (CLOCK) genes is altered by low doses (5 mJ/cm 2 ) of UVB in the immortalized HaCat HKCs cell line. Although depletion of BMAL1 or CLOCK has no effect on the activation of Rad3-related protein kinases-checkpoint kinase 1-p53 mediated DNA damage checkpoints, it leads to suppression of UVB-stimulated apoptotic responses, and downregulation of UVB-elevated expression of DNA damage marker γ-H2AX and cell cycle inhibitor p21. Diminished apoptotic responses are also observed in primary HKCs depleted of BMAL1 or CLOCK after UVB irradiation. While CLOCK depletion shows a suppressive effect on UVB-induced p53 protein accumulation, depletion of either clock gene triggers early keratinocyte differentiation of HKCs at their steady state. These results suggest that UVB-induced apoptosis and DNA damage responses are controlled by clock proteins, but via different mechanisms in the immortalized human adult low calcium temperature and primary HKCs. Given the implication of UVB in photoaging and photocarcinogenesis, mechanistic elucidation of circadian controls on UVB effects in human skin will be critical and beneficial for prevention and treatment of skin cancers and other skin-related diseases. © 2018 Wiley Periodicals, Inc.

Interspecific Variability in Sensitivity to UV Radiation and Subsequent Recovery in Selected Isolates of Marine Bacteria†

PubMed Central

Arrieta, Jesús María; Weinbauer, Markus G.; Herndl, Gerhard J.

2000-01-01

The interspecific variability in the sensitivity of marine bacterial isolates to UV-B (295- to 320-nm) radiation and their ability to recover from previous UV-B stress were examined. Isolates originating from different microenvironments of the northern Adriatic Sea were transferred to aged seawater and exposed to artificial UV-B radiation for 4 h and subsequently to different radiation regimens excluding UV-B to determine the recovery from UV-B stress. Bacterial activity was assessed by thymidine and leucine incorporation measurements prior to and immediately after the exposure to UV-B and after the subsequent exposure to the different radiation regimens. Large interspecific differences among the 11 bacterial isolates were found in the sensitivity to UV-B, ranging from 21 to 92% inhibition of leucine incorporation compared to the bacterial activity measured in dark controls and from 14 to 84% for thymidine incorporation. Interspecific differences in the recovery from the UV stress were also large. An inverse relation was detectable between the ability to recover under dark conditions and the recovery under photosynthetic active radiation (400 to 700 nm). The observed large interspecific differences in the sensitivity to UV-B radiation and even more so in the subsequent recovery from UV-B stress are not related to the prevailing radiation conditions of the microhabitats from which the bacterial isolates originate. Based on our investigations on the 11 marine isolates, we conclude that there are large interspecific differences in the sensitivity to UV-B radiation and even larger differences in the mechanisms of recovery from previous UV stress. This might lead to UV-mediated shifts in the bacterioplankton community composition in marine surface waters. PMID:10742228

68Ga-PSMA-11 PET/CT-derived metabolic parameters for determination of whole-body tumor burden and treatment response in prostate cancer.

PubMed

Schmidkonz, Christian; Cordes, Michael; Schmidt, Daniela; Bäuerle, Tobias; Goetz, Theresa Ida; Beck, Michael; Prante, Olaf; Cavallaro, Alexander; Uder, Michael; Wullich, Bernd; Goebell, Peter; Kuwert, Torsten; Ritt, Philipp

2018-05-03

We aimed at evaluating the role of 68 Ga-PSMA-11 PET/CT-derived metabolic parameters for assessment of whole-body tumor burden and its capability to determine therapeutic response in patients with prostate cancer. A total of 142 patients with biochemical recurrence of prostate cancer underwent PET/CT with [ 68 Ga]Ga-PSMA-HBED-CC ( 68 Ga-PSMA-11). Quantitative assessment of all 641 68 Ga-PSMA-11-positive lesions in the field of view was performed to calculate PSMA-derived parameters, including whole-body PSMA tumor volume (PSMA-TV) and whole-body total lesion PSMA (TL-PSMA), as well as the established SUVmax and SUVmean values. All PET-derived parameters were tested for correlation with serum PSA levels and for association with Gleason scores. In 23 patients who underwent 68 Ga-PSMA-11 PET/CT before and after therapy with either external beam radiation, androgen deprivation, or docetaxel chemotherapy, SUVmax and TL-PSMA were compared to radiographic response assessment of CT images based on RECIST 1.1 criteria and to biochemical response determined by changes of serum PSA levels. PSMA-TV and TL-PSMA demonstrated a significant correlation with serum PSA levels (P < 0.0001) and TL-PSMA was significantly different for different Gleason scores. The agreement rate between TL-PSMA derived from PET and biochemical response was 87% (95% confidence interval, 0.66-0.97; Cohen's κ = 0.78; P < 0.01) and, thus, higher than for SUVmax, which was 74% (95% CI, 0.52-0.90; κ = 0.55; P < 0.01). Furthermore, agreement with PSA was higher for TL-PSMA and SUVmax than for CT-based response evaluation. Discordant findings between PET and CT were most likely due to limitations of CT and RECIST in rating small lymph nodes as metastases, as well as bone involvement, which was sometimes not detectable in CT. 68 Ga-PSMA-11 PET/CT-derived metabolic tumor parameters showed promising results for evaluation of treatment response. Especially, TL-PSMA demonstrated higher agreement rates with biochemical response compared to SUVmax. Larger, ideally prospective trials are needed to help to reveal the full potential of metabolic parameters derived from PET imaging with 68 Ga-PSMA-11.

Influence of ambient ultraviolet radiation on Bufo calamita egg development in a semiarid zone (Catalonia, Spain).

PubMed

Oromi, Neus; Marquis, Olivier; Miaud, Claude; Sanuy, Delfi

2008-01-01

Several experiments have shown that ambient ultraviolet-B radiation (UV-B) has negative effects on the development of amphibians' embryos. We studied the effects of UV-B radiation on development, survival and frequency of deformity during egg development in the Natterjack toad (Bufo calamita) from a semiarid region of Lleida (Catalonia, Spain). Eggs exposed to ambient levels of UV-B and those protected from UV-B with a filter exhibited similar developmental rate, mortality rate and frequency of developmental anomalies. These experiments show that eggs of Bufo calamita of the studied population are able to develop normally during embryonic period when exposed to current high levels of UV-B observed in Catalonia. These results will be used as reference for future studies on geographic variation in UV-B tolerance in this species.

Early exposure to ultraviolet-B radiation decreases immune function later in life

PubMed Central

Ceccato, Emma; Cramp, Rebecca L.; Seebacher, Frank; Franklin, Craig E.

2016-01-01

Amphibians have declined dramatically worldwide. Many of these declines are occurring in areas where no obvious anthropogenic stressors are present. It is proposed that in these areas, environmental factors such as elevated solar ultraviolet-B (UV-B) radiation could be responsible. Ultraviolet-B levels have increased in many parts of the world as a consequence of the anthropogenic destruction of the ozone layer. Amphibian tadpoles are particularly sensitive to the damaging effects of UV-B radiation, with exposure disrupting growth and fitness in many species. Given that UV-B can disrupt immune function in other animals, we tested the hypothesis that early UV-B exposure suppresses the immune responses of amphibian tadpoles and subsequent juvenile frogs. We exposed Limnodynastes peronii tadpoles to sublethal levels of UV-B radiation for 6 weeks after hatching, then examined indices of immune function in both the tadpoles and the subsequent metamorphs. There was no significant effect of UV-B on tadpole leucocyte counts or on their response to an acute antigen (phytohaemagglutinin) challenge. However, early UV-B exposure resulted in a significant reduction in both metamorph leucocyte abundance and their response to an acute phytohaemagglutinin challenge. These data demonstrate that early UV-B exposure can have carry-over effects on later life-history traits even if the applied stressor has no immediately discernible effect. These findings have important implications for our understanding of the effects of UV-B exposure on amphibian health and susceptibility to diseases such as chytridiomycosis. PMID:27668081

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

PubMed

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.

Fisetin inhibits UVB-induced cutaneous inflammation and activation of PI3K/AKT/NFκB signaling pathways in SKH-1 hairless mice.

PubMed

Pal, Harish Chandra; Athar, Mohammad; Elmets, Craig A; Afaq, Farrukh

2015-01-01

Solar ultraviolet B (UVB) radiation has been shown to induce inflammation, DNA damage, p53 mutations and alterations in signaling pathways eventually leading to skin cancer. In this study, we investigated whether fisetin reduces inflammatory responses and modulates PI3K/AKT/NFκB cell survival signaling pathways in UVB-exposed SKH-1 hairless mouse skin. Mice were exposed to 180 mJ cm(-2) of UVB radiation on alternate days for a total of seven exposures, and fisetin (250 and 500 nmol) was applied topically after 15 min of each UVB exposure. Fisetin treatment to UVB-exposed mice resulted in decreased hyperplasia and reduced infiltration of inflammatory cells. Fisetin treatment also reduced inflammatory mediators such as COX-2, PGE2 as well as its receptors (EP1-EP4) and MPO activity. Furthermore, fisetin reduced the level of inflammatory cytokines TNFα, IL-1β and IL-6 in UVB-exposed skin. Fisetin treatment also reduced cell proliferation markers as well as DNA damage as evidenced by increased expression of p53 and p21 proteins. Further studies revealed that fisetin inhibited UVB-induced expression of PI3K, phosphorylation of AKT and activation of the NFκB signaling pathway in mouse skin. Overall, these data suggest that fisetin may be useful against UVB-induced cutaneous inflammation and DNA damage. © 2014 The American Society of Photobiology.

Changes of MMP-1 and collagen type Ialpha1 by UVA, UVB and IRA are differentially regulated by Trx-1.

PubMed

Buechner, Nicole; Schroeder, Peter; Jakob, Sascha; Kunze, Kerstin; Maresch, Tanja; Calles, Christian; Krutmann, Jean; Haendeler, Judith

2008-07-01

Exposure of human skin to solar radiation, which includes ultraviolet (UV) radiation (UVA and UVB) visible light and infrared radiation, induces skin aging. The effects of light have been attributed to irradiation-induced reactive oxygen species (ROS) formation, but the specific signaling pathways are not well understood. Detrimental effects of solar radiation are dermal diseases and photoaging. Exposure of cultured human dermal fibroblasts to UVA, UVB or IRA increased ROS formation in vitro. One important redox regulator is the oxidoreductase thioredoxin-1 (Trx). Trx is ubiquitously expressed and has anti-oxidative and anti-apoptotic properties. Besides its function to reduce H(2)O(2), Trx binds to and regulates transcription factors. The aim of this study was to investigate whether Trx influences the regulation of MMP-1 and collagen Ialpha1 by UVA, UVB and IRA. We irradiated human dermal fibroblasts with UVA, UVB and IRA. UVA, UVB and IRA upregulated MMP-1 expression. Trx inhibited UVA-induced MMP-1 upregulation in a NFkappaB dependent manner. UVA, UVB and IRA reduced collagen Ialpha1 expression. Incubation with Trx inhibited the effects of UVB and IRA on collagen Ialpha1 expression. In conclusion, MMP-1 and collagen Ialpha1, which play important roles in aging processes, seems to be regulated by different transcriptional mechanisms and Trx can only influence distinct signaling pathways induced by UVA, UVB and probably IRA. Thus, Trx may serve as an important contributor to an "anti-aging therapeutic cocktail".

Acclimation to UV-B radiation and visible light in Lactuca sativa involves up-regulation of photosynthetic performance and orchestration of metabolome-wide responses.

PubMed

Wargent, J J; Nelson, B C W; McGhie, T K; Barnes, P W

2015-05-01

UV-B radiation is often viewed as a source of stress for higher plants. In particular, photosynthetic function has been described as a common target for UV-B impairment; yet as our understanding of UV-B photomorphogenesis increases, there are opportunities to expand the emerging paradigm of regulatory UV response. Lactuca sativa is an important dietary crop species and is often subjected to rapid sunlight exposure at field transfer. Acclimation to UV-B and visible light conditions in L. sativa was dissected using gas exchange and chlorophyll fluorescence measurements, in addition to non-destructive assessments of UV epidermal shielding (SUV ). After UV-B treatment, seedlings were subjected to wide-range metabolomic analysis using liquid chromatography hybrid quadrupole time-of-flight high-resolution mass spectrometry (LC-QTOF-HRMS). During the acclimation period, net photosynthetic rate increased in UV-treated plants, epidermal UV shielding increased in both subsets of plants transferred to the acclimatory conditions (UV+/UV- plants) and Fv /Fm declined slightly in UV+/UV- plants. Metabolomic analysis revealed that a key group of secondary compounds was up-regulated by higher light conditions, yet several of these compounds were elevated further by UV-B radiation. In conclusion, acclimation to UV-B radiation involves co-protection from the effects of visible light, and responses to UV-B radiation at a photosynthetic level may not be consistently viewed as damaging to plant development. © 2014 John Wiley & Sons Ltd.

Comparative analysis of the relative potential of silver, zinc-oxide and titanium-dioxide nanoparticles against UVB-induced DNA damage for the prevention of skin carcinogenesis

PubMed Central

Arora, Sumit; Omar, Yousef; Ijaz, Zohaib Mohammad; AL-Ghadhban, Ahmed; Deshmukh, Sachin K.; Carter, James E.; Singh, Ajay P.; Singh, Seema

2016-01-01

Sunscreen formulations containing UVB filters, such as Zinc-oxide (ZnO) and titanium-dioxide (TiO2) nanoparticles (NPs) have been developed to limit the exposure of human skin to UV-radiations. Unfortunately, these UVB protective agents have failed in controlling the skin cancer incidence. We recently demonstrated that silver nanoparticles (Ag-NPs) could serve as novel protective agents against UVB-radiations. Here our goal was to perform comparative analysis of direct and indirect UVB-protection efficacy of ZnO-, TiO2- and Ag-NPs. Sun-protection-factor calculated based on their UVB-reflective/absorption abilities was the highest for TiO2-NPs followed by Ag- and ZnO-NPs. This was further confirmed by studying indirect protection of UVB radiation-induced death of HaCaT cells. However, only Ag-NPs were active in protecting HaCaT cells against direct UVB-induced DNA-damage by repairing bulky-DNA lesions through nucleotide-excision-repair mechanism. Moreover, Ag-NPs were also effective in protecting HaCaT cells from UVB-induced oxidative DNA damage by enhancing SOD/CAT/GPx activity. In contrast, ZnO- and TiO2-NPs not only failed in providing any direct protection from DNA-damage, but rather enhanced oxidative DNA-damage by increasing ROS production. Together, these findings raise concerns about safety of ZnO- and TiO2-NPs and establish superior protective efficacy of Ag-NPs. PMID:27693632

Leaf expansion and development of photosynthetic capacity and pigments in Liquidambar Styraciflua (Hamamelidaceae)-effects of UV-B radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dillenburg, L.R.; Sullivan, J.H.; Teramura, A.H.

1995-07-01

In order to perform their functions as photosynthetic organs, leaves must cope with excess heat and potentially damaging ultraviolet radiation. Possible increases in the UV-B portion of the solar spectrum may place an additional burden on leaves, and this could be particularly important for young expanding leaves with poorly developed UV-B defense mechanisms. We evaluated the effects of supplemental UV-B radiation on leaf expansion and the development of photosynthetic capacity and pigments in sweetgum (Liquidambar styraciflua L.) seedlings. Seedlings were grown in the field under either ambient or ambient plus 3 or 5.0 kJ of biologically effective supplemental UV-B radiation.more » Although final leaf size was unaffected, the rate of leaf elongation and accumulation of leaf area was slower in leaves exposed to the lower supplemental UV-B irradiance. In contrast, chlorophyll accumulation and the development of photosynthetic capacity was more rapid in plants exposed to the higher, compared to the lower supplemental UV-B irradiance. The accumulation of anthocyanins and other putative flavonoids or UV-absorbing compounds was scarcely affected by exposure to supplemental UV-B radiation. These results suggest that the UV-B portion of the solar spectrum may, in the absence of gross affects on biomass, exert subtle influences on leaf ontogeny and the development of photosynthetic pigments and capacity in sweetgum. 44 refs., 6 figs.« less

UV-B radiation and photosynthetic irradiance acclimate eggplant for outdoor exposure

NASA Technical Reports Server (NTRS)

Latimer, J. G.; Mitchell, C. A.; Mitchell, G. A.

1987-01-01

Treatment of greenhouse-grown eggplant (Solanum melongena L. var. esculentum Nees. 'Burpee's Black Beauty') seedlings with supplemental photosynthetically active radiation from cool-white fluorescent lamps increased growth of plants subsequently transferred outdoors relative to growth of plants that received no supplemental radiation or were shaded to 45% of solar irradiation in the greenhouse before transfer outdoors. Eggplant seedlings transferred outdoors were placed under plastic tarps either to provide relative protection from solar ultraviolet-B (UV-B) radiation (280-315 nm) using Mylar film or to allow exposure to UV-B using cellulose acetate. Protection of seedlings from UV-B radiation resulted in greater leaf expansion than for UV-B-exposed seedlings, but no change in leaf or shoot dry weight occurred after 9 days of treatment. Specific leaf weight increased in response to UV-B exposure outdoors. Exposure of eggplant to UV-B radiation from fluorescent sunlamps in the greenhouse also decreased leaf expansion and leaf and shoot dry weight gain after 5 days of treatment. However, there were no differences in leaf or shoot dry weight relative to control plants after 12 days of UV-B treatment, indicating that UV-B treated plants had acclimated to the treatment and actually had caught up with non-UV-B-irradiated plants in terms of growth.

REPRESSOR OF ULTRAVIOLET-B PHOTOMORPHOGENESIS function allows efficient phototropin mediated ultraviolet-B phototropism in etiolated seedlings.

PubMed

Vanhaelewyn, Lucas; Schumacher, Paolo; Poelman, Dirk; Fankhauser, Christian; Van Der Straeten, Dominique; Vandenbussche, Filip

2016-11-01

Ultraviolet B (UV-B) light is a part of the solar radiation which has significant effects on plant morphology, even at low doses. In Arabidopsis, many of these morphological changes have been attributed to a specific UV-B receptor, UV resistance locus 8 (UVR8). Recent findings showed that next to phototropin regulated phototropism, UVR8 mediated signaling is able of inducing directional bending towards UV-B light in etiolated seedlings of Arabidopsis, in a phototropin independent manner. In this study, kinetic analysis of phototropic bending was used to evaluate the relative contribution of each of these pathways in UV-B mediated phototropism. Diminishing UV-B light intensity favors the importance of phototropins. Molecular and genetic analyses suggest that UV-B is capable of inducing phototropin signaling relying on phototropin kinase activity and regulation of NPH3. Moreover, enhanced UVR8 responses in the UV-B hypersensitive rup1rup2 mutants interferes with the fast phototropin mediated phototropism. Together the data suggest that phototropins are the most important receptors for UV-B induced phototropism in etiolated seedlings, and a RUP mediated negative feedback pathway prevents UVR8 signaling to interfere with the phototropin dependent response. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

UV sensitivity of planktonic net community production in ocean surface waters

NASA Astrophysics Data System (ADS)

Regaudie-de-Gioux, Aurore; Agustí, Susana; Duarte, Carlos M.

2014-05-01

The net plankton community metabolism of oceanic surface waters is particularly important as it more directly affects the partial pressure of CO2 in surface waters and thus the air-sea fluxes of CO2. Plankton communities in surface waters are exposed to high irradiance that includes significant ultraviolet blue (UVB, 280-315 nm) radiation. UVB radiation affects both photosynthetic and respiration rates, increase plankton mortality rates, and other metabolic and chemical processes. Here we test the sensitivity of net community production (NCP) to UVB of planktonic communities in surface waters across contrasting regions of the ocean. We observed here that UVB radiation affects net plankton community production at the ocean surface, imposing a shift in NCP by, on average, 50% relative to the values measured when excluding partly UVB. Our results show that under full solar radiation, the metabolic balance shows the prevalence of net heterotrophic community production. The demonstration of an important effect of UVB radiation on NCP in surface waters presented here is of particular relevance in relation to the increased UVB radiation derived from the erosion of the stratospheric ozone layer. Our results encourage design future research to further our understanding of UVB effects on the metabolic balance of plankton communities.

The role of lipid raft translocation of prohibitin in regulation of Akt and Raf-protected apoptosis of HaCaT cells upon ultraviolet B irradiation.

PubMed

Wu, Qiong; Wu, Shiyong

2017-07-01

Prohibitin (PHB) plays a role in regulation of ultraviolet B light (UVB)-induced apoptosis of human keratinocytes, HaCaT cells. The regulatory function of PHB appears to be associated with its lipid raft translocation. However, the detailed mechanism for PHB-mediated apoptosis of these keratinocytes upon UVB irradiation is not clear. In this report, we determined the role of lipid raft translocation of PHB in regulation of UVB-induced apoptosis. Our data show that upon UVB irradiation PHB is translocated from the non-raft membrane to the lipid rafts, which is correlated with a release of both Akt and Raf from membrane. Overexpression of Akt and/or Raf impedes UVB-induced lipid raft translocation of PHB. Immunoprecipitation analysis indicates that UVB alters the interactions among PHB, Akt, and Raf. Reduced expression of PHB leads to a decreased phosphorylation of Akt and ERK, as well as a decreased activity of Akt, and increased apoptosis of the cells upon UVB irradiation. These results suggest that PHB regulates UVB-induced apoptosis of keratinocytes via a mechanism that involves detachment from Akt and Raf on the plasma membrane, and sequential lipid raft translocation. © 2017 Wiley Periodicals, Inc.

Inhibition of Ultraviolet B-Induced Expression of the Proinflammatory Cytokines TNF-α and VEGF in the Cornea by Fucoxanthin Treatment in a Rat Model.

PubMed

Chen, Shiu-Jau; Lee, Ching-Ju; Lin, Tzer-Bin; Liu, Hsiang-Jui; Huang, Shuan-Yu; Chen, Jia-Zeng; Tseng, Kuang-Wen

2016-01-07

Ultraviolet B (UVB) irradiation is the most common cause of radiation damage to the eyeball and is a risk factor for human corneal damage. We determined the protective effect of fucoxanthin, which is a carotenoid found in common edible seaweed, on ocular tissues against oxidative UVB-induced corneal injury. The experimental rats were intravenously injected with fucoxanthin at doses of 0.5, 5 mg/kg body weight/day or with a vehicle before UVB irradiation. Lissamine green for corneal surface staining showed that UVB irradiation caused serious damage on the corneal surface, including severe epithelial exfoliation and deteriorated epithelial smoothness. Histopathological lesion examination revealed that levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF), significantly increased. However, pretreatment with fucoxanthin inhibited UVB radiation-induced corneal disorders including evident preservation of corneal surface smoothness, downregulation of proinflammatory cytokine expression, and decrease of infiltrated polymorphonuclear leukocytes from UVB-induced damage. Moreover, significant preservation of the epithelial integrity and inhibition of stromal swelling were also observed after UVB irradiation in fucoxanthin-treated groups. Pretreatment with fucoxanthin may protect against UVB radiation-induced corneal disorders by inhibiting expression of proinflammatory factors, TNF-α, and VEGF and by blocking polymorphonuclear leukocyte infiltration.

SIRT1 activation mediates heat-induced survival of UVB damaged Keratinocytes.

PubMed

Calapre, Leslie; Gray, Elin S; Kurdykowski, Sandrine; David, Anthony; Descargues, Pascal; Ziman, Mel

2017-06-10

Exposure to heat stress after UVB irradiation induces a reduction of apoptosis, resulting in survival of DNA damaged human keratinocytes. This heat-mediated evasion of apoptosis appears to be mediated by activation of SIRT1 and inactivation of p53 signalling. In this study, we assessed the role of SIRT1 in the inactivation of p53 signalling and impairment of DNA damage response in UVB plus heat exposed keratinocytes. Activation of SIRT1 after multiple UVB plus heat exposures resulted in increased p53 deacetylation at K382, which is known to affect its binding to specific target genes. Accordingly, we noted decreased apoptosis and down regulation of the p53 targeted pro-apoptotic gene BAX and the DNA repair genes ERCC1 and XPC after UVB plus heat treatments. In addition, UVB plus heat induced increased expression of the cell survival gene Survivin and the proliferation marker Ki67. Notably, keratinocytes exposed to UVB plus heat in the presence of the SIRT1 inhibitor, Ex-527, showed a similar phenotype to those exposed to UV alone; i.e. an increase in p53 acetylation, increased apoptosis and low levels of Survivin. This study demonstrate that heat-induced SIRT1 activation mediates survival of DNA damaged keratinocytes through deacetylation of p53 after exposure to UVB plus heat.

UV-B radiation and photosynthetic irradiance acclimate eggplant for outdoor exposure.

PubMed

Latimer, J G; Mitchell, C A; Mitchell, G A

1987-06-01

Treatment of greenhouse-grown eggplant (Solanum melongena L. var. esculentum Nees. 'Burpee's Black Beauty') seedlings with supplemental photosynthetically active radiation from cool-white fluorescent lamps increased growth of plants subsequently transferred outdoors relative to growth of plants that received no supplemental radiation or were shaded to 45% of solar irradiation in the greenhouse before transfer outdoors. Eggplant seedlings transferred outdoors were placed under plastic tarps either to provide relative protection from solar ultraviolet-B (UV-B) radiation (280-315 nm) using Mylar film or to allow exposure to UV-B using cellulose acetate. Protection of seedlings from UV-B radiation resulted in greater leaf expansion than for UV-B-exposed seedlings, but no change in leaf or shoot dry weight occurred after 9 days of treatment. Specific leaf weight increased in response to UV-B exposure outdoors. Exposure of eggplant to UV-B radiation from fluorescent sunlamps in the greenhouse also decreased leaf expansion and leaf and shoot dry weight gain after 5 days of treatment. However, there were no differences in leaf or shoot dry weight relative to control plants after 12 days of UV-B treatment, indicating that UV-B treated plants had acclimated to the treatment and actually had caught up with non-UV-B-irradiated plants in terms of growth.

Photoprotective substance occurs primarily in outer layers of fish skin

USGS Publications Warehouse

Fabacher, D.L.; Little, E.E.

1998-01-01

Methanol extracts of dorsal skin layers, eyes, gills, and livers from ultraviolet-B (UVB) radiation-sensitive and UVB-tolerant species of freshwater fish were examined for a substance that appears to be photoprotective. Significantly larger amounts of this substance were found in extracts of outer dorsal skin layers from both UVB-sensitive and UVB-tolerant fish when compared with extracts of inner dorsal skin layers. This substance occurred in minor amounts or was not detected in eye, gill, and liver extracts. The apparent primary function of this substance in fish is to protect the cells in outer dorsal skin layers from harmful levels of UVB radiation.

Photoprotective substance occurs primarily in outer layers of fish skin.

PubMed

Fabacher, D L; Little, E E

1998-01-01

Methanol extracts of dorsal skin layers, eyes, gills, and livers from ultraviolet-B (UVB) radiation-sensitive and UVB-tolerant species of freshwater fish were examined for a substance that appears to be photoprotective. Significantly larger amounts of this substance were found in extracts of outer dorsal skin layers from both UVB-sensitive and UVB-tolerant fish when compared with extracts of inner dorsal skin layers. This substance occurred in minor amounts or was not detected in eye, gill, and liver extracts. The apparent primary function of this substance in fish is to protect the cells in outer dorsal skin layers from harmful levels of UVB radiation.

Saponins from Tribulus terrestris L. protect human keratinocytes from UVB-induced damage.

PubMed

Sisto, Margherita; Lisi, Sabrina; D'Amore, Massimo; De Lucro, Raffaella; Carati, Davide; Castellana, Donatello; La Pesa, Velia; Zuccarello, Vincenzo; Lofrumento, Dario D

2012-12-05

Chronic exposure to solar UVB radiation damages skin, increasing the risk to develop cancer. Hence the identification of compounds with a photoprotective efficacy is essential. This study examined the role of saponins derived from Tribulus terrestris L. (TT) on the modulation of apoptosis in normal human keratinocytes (NHEK) exposed to physiological doses of UVB and to evaluate their antitumoral properties. In NHEK, TT saponins attenuate UVB-induced programmed cell death through inhibition of intrinsic apoptotic pathway. In squamous cell carcinomas (SCC) TT saponins do not make the malignant keratinocytes more resistant to UVB and determine an enhanced apoptotic response. The photoprotective effect of TT saponins is tightly correlated to the enhancement of NER genes expression and the block of UVB-mediated NF-κB activation. Collectively, our study shows experimental evidence that TT has a preventive efficacy against UVB-induced carcinogenesis and the molecular knowledge on the mechanisms through which TT saponins regulate cell death suggests great potential for TT to be developed into a new medicine for cancer patients. Copyright © 2012 Elsevier B.V. All rights reserved.

Myricetin inhibits UVB-induced angiogenesis by regulating PI-3 kinase in vivo

PubMed Central

Jung, Sung Keun; Lee, Ki Won; Byun, Sanguine; Lee, Eun Jung; Kim, Jong-Eun; Bode, Ann M.; Dong, Zigang

2010-01-01

Myricetin is one of the principal phytochemicals in onions, berries and red wine. Previous studies showed that myricetin exhibits potent anticancer and chemopreventive effects. The present study examined the effect of myricetin on ultraviolet (UV) B-induced angiogenesis in an SKH-1 hairless mouse skin tumorigenesis model. Topical treatment with myricetin inhibited repetitive UVB-induced neovascularization in SKH-1 hairless mouse skin. The induction of vascular endothelial growth factor, matrix metalloproteinase (MMP)-9 and MMP-13 expression by chronic UVB irradiation was significantly suppressed by myricetin treatment. Immunohistochemical and western blot analyses revealed that myricetin inhibited UVB-induced hypoxia inducible factor-1α expression in mouse skin. Western blot analysis and kinase assay data revealed that myricetin suppressed UVB-induced phosphatidylinositol-3 (PI-3) kinase activity and subsequently attenuated the UVB-induced phosphorylation of Akt/p70S6K in mouse skin lysates. A pull-down assay revealed the direct binding of PI-3 kinase and myricetin in mouse skin lysates. Our results indicate that myricetin suppresses UVB-induced angiogenesis by regulating PI-3 kinase activity in vivo in mouse skin. PMID:20008033

UV-B Radiation Contributes to Amphibian Population Declines

NASA Astrophysics Data System (ADS)

Blaustein, Andrew

2007-05-01

UV-B (280-315 nm) radiation is the most significant biologically damaging radiation at the terrestrial surface. At the organismal level, UV-B radiation can slow growth rates, cause immune dysfunction and result in sublethal damage. UV-B radiation can lead to mutations and cell death. Over evolutionary time, UV radiation has been an important stressor on living organisms. Natural events, including impacts from comets and asteroids, volcanic activity, supernova explosions and solar flares, can cause large-scale ozone depletion with accompanying increases in UV radiation. However, these natural events are transient. Moreover, the amount of ozone damage due to natural events depends upon a number of variables, including the magnitude of the event. This is different from modern-day human-induced production of chlorofluorocarbons (CFCs) and other chemicals that deplete stratospheric ozone continuously, resulting in long-term increases in UV-B radiation at the surface of the earth. We will briefly review the effects of UV-B exposure in one group of aquatic organisms_amphibians. UV-B has been implicated as a possible factor contributing to global declines and range reductions in amphibian populations.

Quercitrin Protects Skin from UVB-induced Oxidative Damage

PubMed Central

Yin, Yuanqin; Li, Wenqi; Son, Yong-Ok; Sun, Lijuan; Lu, Jian; Kim, Donghern; Wang, Xin; Yao, Hua; Wang, Lei; Pratheeshkumar, Poyil; Hitron, Andrew J; Luo, Jia; Gao, Ning; Shi, Xianglin; Zhang, Zhuo

2013-01-01

Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidative damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin. PMID:23545178

Oral administration of Aloe vera gel powder prevents UVB-induced decrease in skin elasticity via suppression of overexpression of MMPs in hairless mice.

PubMed

Saito, Marie; Tanaka, Miyuki; Misawa, Eriko; Yao, Ruiquing; Nabeshima, Kazumi; Yamauchi, Kouji; Abe, Fumiaki; Yamamoto, Yuki; Furukawa, Fukumi

2016-07-01

This study reports the effects of oral Aloe vera gel powder (AVGP) containing Aloe sterols on skin elasticity and the extracellular matrix in ultraviolet B (UVB)-irradiated hairless mice. Ten-week-old hairless mice were fed diets containing 0.3% AVGP for 8 weeks and irradiated UVB for 6 weeks. Mice treated with AVGP showed significant prevention of the UVB-induced decrease in skin elasticity. To investigate the mechanism underlying this suppression of skin elasticity loss, we measured the expression of matrix metalloproteinase (MMP)-2, -9, and -13. AVGP prevented both the UVB-induced increases in MMPs expressions. Moreover, we investigated hyaluronic acid (HA) content of mice dorsal skin and gene expression of HA synthase-2 (Has2). In the results, AVGP oral administration prevented UVB-induced decreasing in skin HA content and Has2 expression and attenuates the UVB-induced decrease in serum adiponectin, which promotes Has2 expression. These results suggested that AVGP has the ability to prevent the skin photoaging.

Quercitrin protects skin from UVB-induced oxidative damage.

PubMed

Yin, Yuanqin; Li, Wenqi; Son, Young-Ok; Sun, Lijuan; Lu, Jian; Kim, Donghern; Wang, Xin; Yao, Hua; Wang, Lei; Pratheeshkumar, Poyil; Hitron, Andrew J; Luo, Jia; Gao, Ning; Shi, Xianglin; Zhang, Zhuo

2013-06-01

Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidative damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin. Copyright © 2013 Elsevier Inc. All rights reserved.

Study of Hydroquinone Mediated Cytotoxicity and Hypopigmentation Effects from UVB-Irradiated Arbutin and DeoxyArbutin

PubMed Central

Chang, Nai-Fang; Chen, Yi-Shyan; Lin, Ying-Ju; Tai, Ting-Hsuan; Chen, An-Ni; Huang, Chen-Hsuan; Lin, Chih-Chien

2017-01-01

Arbutin (Arb) and deoxyArbutin (dA) are both effective hypopigmentation agents. However, they are glucoside derivatives of hydroquinone (HQ), which may be decayed into HQ under higher energy environments. Therefore, safety and toxicity are very important issues when considering the usage of these compounds. However, no study has verified the properties of Ultra-Violet B (UVB)-irradiated Arb and dA. In this work, we investigated the cytotoxicity and hypopigmentation effects of UVB-irradiated Arb and dA in Detroit 551 human fibroblast cells and B16-F10 mouse melanoma cells. The results showed that UVB-irradiated Arb and dA have strong cytotoxicity for the fibroblast cells, especially for dA, the caspase-3 is also activated by the treatment of UVB-irradiated dA in Detroit 551 cells. The results correlated with the produced HQ. In addition, UVB-irradiated Arb and dA suppressed the production of melanin in melanoma cells; this is due to the release of HQ that compensates for the UVB triggered Arb and dA decomposition. PMID:28467382

Study of Hydroquinone Mediated Cytotoxicity and Hypopigmentation Effects from UVB-Irradiated Arbutin and DeoxyArbutin.

PubMed

Chang, Nai-Fang; Chen, Yi-Shyan; Lin, Ying-Ju; Tai, Ting-Hsuan; Chen, An-Ni; Huang, Chen-Hsuan; Lin, Chih-Chien

2017-05-03

Arbutin (Arb) and deoxyArbutin (dA) are both effective hypopigmentation agents. However, they are glucoside derivatives of hydroquinone (HQ), which may be decayed into HQ under higher energy environments. Therefore, safety and toxicity are very important issues when considering the usage of these compounds. However, no study has verified the properties of Ultra-Violet B (UVB)-irradiated Arb and dA. In this work, we investigated the cytotoxicity and hypopigmentation effects of UVB-irradiated Arb and dA in Detroit 551 human fibroblast cells and B16-F10 mouse melanoma cells. The results showed that UVB-irradiated Arb and dA have strong cytotoxicity for the fibroblast cells, especially for dA, the caspase-3 is also activated by the treatment of UVB-irradiated dA in Detroit 551 cells. The results correlated with the produced HQ. In addition, UVB-irradiated Arb and dA suppressed the production of melanin in melanoma cells; this is due to the release of HQ that compensates for the UVB triggered Arb and dA decomposition.

Coordinated photomorphogenic UV-B signaling network captured by mathematical modeling.

PubMed

Ouyang, Xinhao; Huang, Xi; Jin, Xiao; Chen, Zheng; Yang, Panyu; Ge, Hao; Li, Shigui; Deng, Xing Wang

2014-08-05

Long-wavelength and low-fluence UV-B light is an informational signal known to induce photomorphogenic development in plants. Using the model plant Arabidopsis thaliana, a variety of factors involved in UV-B-specific signaling have been experimentally characterized over the past decade, including the UV-B light receptor UV resistance locus 8; the positive regulators constitutive photomorphogenesis 1 and elongated hypocotyl 5; and the negative regulators cullin4, repressor of UV-B photomorphogenesis 1 (RUP1), and RUP2. Individual genetic and molecular studies have revealed that these proteins function in either positive or negative regulatory capacities for the sufficient and balanced transduction of photomorphogenic UV-B signal. Less is known, however, regarding how these signaling events are systematically linked. In our study, we use a systems biology approach to investigate the dynamic behaviors and correlations of multiple signaling components involved in Arabidopsis UV-B-induced photomorphogenesis. We define a mathematical representation of photomorphogenic UV-B signaling at a temporal scale. Supplemented with experimental validation, our computational modeling demonstrates the functional interaction that occurs among different protein complexes in early and prolonged response to photomorphogenic UV-B.

Effect of dopants on the TL response of the new LiF:Mg,Cu,Ag material

NASA Astrophysics Data System (ADS)

Yahyaabadi, A.; Torkzadeh, F.; Rezaei-Ochbelagh, D.; Hosseini Pooya, M.

2018-07-01

The new TL LiF:Mg,Cu,Ag material was prepared and investigated in this study. The TL intensity of LiF:Mg,Cu,Ag is strongly dependent on the concentration of dopants and the preparation procedure. Any small change in these factors can cause alterations in TL response. In this study, the influence of Cu and Ag concentrations on the response of the LiF:Mg,Cu,Ag sample was investigated and showed that the height of the low, main and high temperature peaks changes with Ag concentration. Their intensities increased with increasing Ag concentration to a maximum value and decreased with higher Ag concentration. It was also found that Cu concentration less than 0.05 mol% influences the maximum peak height and TL intensity. The optimum Cu and Ag concentrations were found to be 0.05 and 0.1 mol% at 1005 °C QT, respectively. The role of dopants in LiF:Mg,Cu,Ag material was also investigated. The results showed that presence of three dopants is important for having material with sensitivity higher than LiF:Mg,Ti. The Mg dopant plays a crucial role in the formation of the trapping center and the position of the main dosimetric peak.

History of phototherapy in dermatology.

PubMed

Hönigsmann, Herbert

2013-01-01

Over many centuries, treatment with sunlight or "heliotherapy" was used in the treatment of skin diseases. More than 3500 years ago, ancient Egyptian and Indian healers used the ingestion of plant extracts or seeds in addition to sunlight for treating "leucoderma". Modern phototherapy began with Nobel Prize winner Niels Finsen who developed a "chemical rays" lamp with which he treated patients with skin tuberculosis. However, it took several decades until phototherapy was introduced anew into the dermatological armamentarium. It was the development of photochemotherapy (PUVA) in 1974 that marked the beginning of a huge upsurge in photodermatology. The subsequent development of high intensity UV sources with defined spectra facilitated an optimized therapy for psoriasis and led to an expansion of indications for photo(chemo)therapy also in combination with topical and systemic agents. The introduction of extracorporeal photopheresis in 1987 for cutaneous T-cell lymphoma and of topical photodynamic therapy widely expanded the therapeutic possibilities in dermato-oncology.

Improvement of the light-tissue coupling for better outcome of phototherapies

NASA Astrophysics Data System (ADS)

da Silva, Dilleys Ferreira; Vollet Filho, José Dirceu; Fortunato, Thereza Cury; Moriyama, Lilian Tan; Grecco, Clovis; Pratavieira, Sebastião.; Kurachi, Cristina; Bagnato, Vanderlei Salvador

2018-02-01

Phototherapies have been increasingly used in several applications such as the control of pain and inflammatory processes, photodynamic therapy, and even aesthetics uses. After many decades, the dosimetry for those techniques remains challenging. One of the key issues is the lack of homogeneity obtained for tissue illumination, which may limit adequate treatment. Especially concerning lesions, the surface tissue is usually irregular, and the light does not couple to the tissue efficiently to promote an effective treatment. A series of experiments have been performed using optical phantoms, in which coupling was improved by introducing a gel with a low concentration of scattering agents between the fiber and the phantom as an attempt to improve the homogeneity of light distribution within the phantoms. The effects promoted by roughness on phantom tissue surfaces are considerably attenuated when the coupling gel was introduced, resulting in a more uniform illumination pattern that may be used to promote better phototherapy treatments outcome.

Iron-based radiochromic systems for UV dosimetry applications

NASA Astrophysics Data System (ADS)

Lee, Hannah J.; Alqathami, Mamdooh; Blencowe, Anton; Ibbott, Geoffrey

2018-01-01

Phototherapy treatment using ultraviolet (UV) A and B light sources has long existed as a treatment option for various skin conditions. Quality control for phototherapy treatment recommended by the British Association of Dermatologists and British Photodermatology Group generally focused on instrumentation-based dosimetry measurements. The purpose of this study was to present an alternative, easily prepared dosimeter system for the measurement of UV dose and as a simple quality assurance technique for phototherapy treatments. Five different UVA-sensitive radiochromic dosimeter formulations were investigated and responded with a measurable and visible optical change both in solution and in gel form. Iron(III) reduction reaction formulations were found to be more sensitive to UVA compared to iron(II) oxidation formulations. One iron(III) reduction formulation was found to be especially promising due to its sensitivity to UVA dose, ease of production, and linear response up to a saturation point.

Inclusion of an ultraviolet radiation transfer component in an urban forest effects model for predicting tree influences on potential below-canopy exposure to UVB radiation

Treesearch

Gordon M. Heisler; Richard H. Grant; David J. Nowak; Wei Gao; Daniel E. Crane; Jeffery T. Walton

2003-01-01

Evaluating the impact of ultraviolet-B radiation (UVB) on urban populations would be enhanced by improved predictions of the UVB radiation at the level of human activity. This paper reports the status of plans for incorporating a UVB prediction module into an existing Urban Forest Effects (UFORE) model. UFORE currently has modules to quantify urban forest structure,...

Molecular mechanisms of UVB-induced senescence of dermal fibroblasts and its relevance for photoaging of the human skin.

PubMed

Cavinato, Maria; Jansen-Dürr, Pidder

2017-08-01

Due to its ability to cross the epidermis and reach the upper dermis where it causes cumulative DNA damage and increased oxidative stress, UVB is considered the most harmful component of sunlight to the skin. The consequences of chronic exposition to UVB are related to photoaging and photocarcinogenesis. There are limitations to the study of human skin aging and for this reason the use of models is required. Human dermal fibroblasts submitted to mild and repeated doses of UVB are considered a versatile model to study UVB effects in the process of skin photoaging, which depends on the accumulation of senescent cells, in particular in the dermis. Here we provide updated information about the current model of UVB-induced senescence with special emphasis on the process of protein quality control. Copyright © 2017 Elsevier Inc. All rights reserved.

Differential sensitivity of spinach and amaranthus to enhanced UV-B at varying soil nutrient levels: association with gas exchange, UV-B-absorbing compounds and membrane damage.

PubMed

Singh, Suruchi; Agrawal, Madhoolika; Agrawal, S B

2013-07-01

The metabolic reasons associated with differential sensitivity of C3 and C4 plant species to enhanced UV-B under varying soil nutrient levels are not well understood. In the present study, spinach (Spinacia oleracea L. var All Green), a C3 and amaranthus (Amaranthus tricolor L. var Pusa Badi Chaulai), a C4 plant were subjected to enhanced UV-B (280-315 nm; 7.2 kJ m(-2) day(-1)) over ambient under varying soil nutrient levels. The nutrient amendments were recommended Nitrogen (N), Phosphorus (P), Potassium (K), 1.5× recommended NPK, 1.5× recommended N and 1.5× recommended K. Enhanced UV-B negatively affected both the species at all nutrient levels, but the reductions varied with nutrient concentration and combinations. Reductions in photosynthetic rate, stomatal conductance and chlorophyll content were significantly more in spinach compared with amaranthus. The reduction in photosynthetic rate was maximum at 1.5× recommended K and minimum in 1.5× NPK amended plants. The oxidative damage to membranes measured in terms of malondialdehyde content was significantly higher in spinach compared with amaranthus. Enhanced UV-B reduced SOD activity in both the plants except in amaranthus at 1.5× recommended K. POX activity increased under enhanced UV-B at all nutrient levels in amaranthus, but only at 1.5× K in spinach. Amaranthus had significantly higher UV-B-absorbing compounds than spinach even under UV-B stress. Lowest reductions in yield and total biomass under enhanced UV-B compared with ambient were observed in amaranthus grown at 1.5× recommended NPK. Enhanced UV-B did not significantly change the nitrogen use efficiency in amaranthus at all NPK levels, but reduced in spinach except at 1.5× K. These findings suggest that the differential sensitivity of the test species under enhanced UV-B at varying nutrient levels is due to varying antioxidative and UV-B screening capacity, and their ability to utilize nutrients. Amaranthus tolerated enhanced UV-B stress more than spinach at all nutrient levels and 1.5× recommended NPK lowered the sensitivity maximally to enhanced UV-B with respect to photosynthesis, biomass and yield. PCA score has also confirmed the lower sensitivity of amaranthus compared with spinach with respect to the measured physiological and biochemical parameters.

Interactive effects of elevated ozone and UV-B radiation on soil nematode diversity.

PubMed

Bao, Xuelian; Li, Qi; Hua, Jianfeng; Zhao, Tianhong; Liang, Wenju

2014-01-01

Ultraviolet-B (UV-B) radiation and elevated tropospheric ozone may cause reductions in the productivity and quality of important agricultural crops. However, research regarding their interactive effect is still scarce, especially on the belowground processes. Using the open top chambers experimental setup, we monitored the response of soil nematodes to the elevated O3 and UV-B radiation individually as well as in combination. Our results indicated that elevated O3 and UV-B radiation have impact not only on the belowground biomass of plants, but also on the community structure and functional diversity of soil nematodes. The canonical correspondence analysis suggested that soil pH, shoot biomass and microbial biomass C and N were relevant parameters that influencing soil nematode distribution. The interactive effects of elevated O3 and UV-B radiation was only observed on the abundance of bacterivores. UV-B radiation significantly increased the abundance of total nematodes and bacterivores in comparison with the control at pod-filling stage of soybean. Following elevated O3, nematode diversity index decreased and dominance index increased relative to the control at pod-filling stage of soybean. Nematode functional diversity showed response to the effects of elevated O3 and UV-B radiation at pod-bearing stage. Higher enrichment index and lower structure index in the treatment with both elevated O3 and UV-B radiation indicated a stressed soil condition and degraded soil food web. However, the ratios of nematode trophic groups suggested that the negative effects of elevated O3 on soil food web may be weakened by the UV-B radiations.

Isolation of a novel UVB-tolerant rice mutant obtained by exposure to carbon-ion beams

PubMed Central

Takano, Nao; Takahashi, Yuko; Yamamoto, Mitsuru; Teranishi, Mika; Yamaguchi, Hiroko; Sakamoto, Ayako N.; Hase, Yoshihiro; Fujisawa, Hiroko; Wu, Jianzhong; Matsumoto, Takashi; Toki, Seiichi; Hidema, Jun

2013-01-01

UVB radiation suppresses photosynthesis and protein biosynthesis in plants, which in turn decreases growth and productivity. Here, an ultraviolet-B (UVB)-tolerant rice mutant, utr319 (UV Tolerant Rice 319), was isolated from a mutagenized population derived from 2500 M1 seeds (of the UVB-resistant cultivar ‘Sasanishiki’) that were exposed to carbon ions. The utr319 mutant was more tolerant to UVB than the wild type. Neither the levels of UVB-induced cyclobutane pyrimidine dimers (CPDs) or (6-4) pyrimidine-pyrimidone photodimers [(6-4) photoproducts], nor the repair of CPDs or (6-4) photoproducts, was altered in the utr319 mutant. Thus, the utr319 mutant may be impaired in the production of a previously unidentified factor that confers UVB tolerance. To identify the mutated region in the utr319 mutant, microarray-based comparative genomic hybridization analysis was performed. Two adjacent genes on chromosome 7, Os07g0264900 and Os07g0265100, were predicted to represent the mutant allele. Sequence analysis of the chromosome region in utr319 revealed a deletion of 45 419 bp. RNAi analysis indicated that Os07g0265100 is most likely the mutated gene. Database analysis indicated that the Os07g0265100 gene, UTR319, encodes a putative protein with unknown characteristics or function. In addition, the homologs of UTR319 are conserved only among land plants. Therefore, utr319 is a novel UVB-tolerant rice mutant and UTR319 may be crucial for the determination of UVB sensitivity in rice, although the function of UTR319 has not yet been determined. PMID:23381954

Ultra-violet B (UVB)-induced skin cell death occurs through a cyclophilin D intrinsic signaling pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ji, Chao; Yang, Bo; Yang, Zhi

Highlights: Black-Right-Pointing-Pointer UVB radiated skin keratinocytes show cyclophilin D (Cyp-D) upregulation. Black-Right-Pointing-Pointer NAC inhibits UVB induced Cyp-D expression, while H{sub 2}O{sub 2} facilitates it. Black-Right-Pointing-Pointer Cyp-D-deficient cells are significantly less susceptible to UVB induced cell death. Black-Right-Pointing-Pointer Over-expression of Cyp-D causes spontaneous keratinocytes cell death. -- Abstract: UVB-induced skin cell damage involves the opening of mitochondrial permeability transition pore (mPTP), which leads to both apoptotic and necrotic cell death. Cyclophilin D (Cyp-D) translocation to the inner membrane of mitochondrion acts as a key component to open the mPTP. Our Western-Blot results in primary cultured human skin keratinocytes and in HaCaTmore » cell line demonstrated that UVB radiation and hydrogen peroxide (H{sub 2}O{sub 2}) induced Cyp-D expression, which was inhibited by anti-oxidant N-acetyl cysteine (NAC). We created a stable Cyp-D deficiency skin keratinocytes by expressing Cyp-D-shRNA through lentiviral infection. Cyp-D-deficient cells were significantly less susceptible than their counterparts to UVB- or H{sub 2}O{sub 2}-induced cell death. Further, cyclosporine A (Cs-A), a Cyp-D inhibitor, inhibited UVB- or H{sub 2}O{sub 2}-induced keratinocytes cell death. Reversely, over-expression of Cyp-D in primary keratinocytes caused spontaneous keratinocytes cell death. These results suggest Cyp-D's critical role in UVB/oxidative stress-induced skin cell death.« less

Resveratrol enhances ultraviolet B-induced cell death through nuclear factor-{kappa}B pathway in human epidermoid carcinoma A431 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roy, Preeti; Kalra, Neetu; Nigam, Nidhi

Resveratrol has been reported to suppress cancer progression in several in vivo and in vitro models, whereas ultraviolet B (UVB), a major risk for skin cancer, is known to induce cell death in cancerous cells. Here, we investigated whether resveratrol can sensitize A431 human epidermoid carcinoma cells to UVB-induced cell death. We examined the combined effect of UVB (30 mJ/cm{sup 2}) and resveratrol (60 {mu}M) on A431 cells. Exposure of A431 carcinoma cells to UVB radiation or resveratrol can inhibit cell proliferation and induce apoptosis. However, the combination of resveratrol and UVB exposure was associated with increased proliferation inhibition ofmore » A431 cells compared with either agent alone. Furthermore, results showed that resveratrol and UVB treatment of A431 cells disrupted the nuclear factor-kappaB (NF-{kappa}B) pathway by blocking phosphorylation of serine 536 and inactivating NF-{kappa}B and subsequent degradation of I{kappa}B{alpha}, which regulates the expression of survivin. Resveratrol and UVB treatment also decreased the phosphorylation of tyrosine 701 of the important transcription factor signal transducer activator of transcription (STAT1), which in turn inhibited translocation of phospho-STAT1 to the nucleus. Moreover, resveratrol/UVB also inhibited the metastatic protein LIMK1, which reduced the motility of A431 cells. In conclusion, our study demonstrates that the combination of resveratrol and UVB act synergistically against skin cancer cells. Thus, resveratrol is a potential chemotherapeutic agent against skin carcinogenesis.« less

Photoprotective Properties of Isothiocyanate and Nitrile Glucosinolate Derivatives From Meadowfoam (Limnanthes alba) Against UVB Irradiation in Human Skin Equivalent

PubMed Central

Carpenter, Evan L.; Le, Mai N.; Miranda, Cristobal L.; Reed, Ralph L.; Stevens, Jan F.; Indra, Arup K.; Ganguli-Indra, Gitali

2018-01-01

Exposure to ultraviolet B (UVB) irradiation of the skin leads to numerous dermatological concerns including skin cancer and accelerated aging. Natural product glucosinolate derivatives, like sulforaphane, have been shown to exhibit chemopreventive and photoprotective properties. In this study, we examined meadowfoam (Limnanthes alba) glucosinolate derivatives, 3-methoxybenzyl isothiocyanate (MBITC) and 3-methoxyphenyl acetonitrile (MPACN), for their activity in protecting against the consequences of UV exposure. To that end, we have exposed human primary epidermal keratinocytes (HPEKs) and 3D human skin reconstructed in vitro (EpiDermTM FT-400) to UVB insult and investigated whether MBITC and MPACN treatment ameliorated the harmful effects of UVB damage. Activity was determined by the compounds’ efficacy in counteracting UVB-induced DNA damage, matrix-metalloproteinase (MMP) expression, and proliferation. We found that in monolayer cultures of HPEK, MBITC and MPACN did not protect against a UVB-induced loss in proliferation and MBITC itself inhibited cell proliferation. However, in human reconstructed skin-equivalents, MBITC and MPACN decrease epidermal cyclobutane pyrimidine dimers (CPDs) and significantly reduce total phosphorylated γH2A.X levels. Both MBITC and MPACN inhibit UVB-induced MMP-1 and MMP-3 expression indicating their role to prevent photoaging. Both compounds, and MPACN in particular, showed activity against UVB-induced proliferation as indicated by fewer epidermal PCNA+ cells and prevented UVB-induced hyperplasia as determined by a reduction in reconstructed skin epidermal thickness (ET). These data demonstrate that MBITC and MPACN exhibit promising anti-photocarcinogenic and anti-photoaging properties in the skin microenvironment and could be used for therapeutic interventions. PMID:29867483

Epigallocatechin-gallate (EGCG) regulates autophagy in human retinal pigment epithelial cells: A potential role for reducing UVB light-induced retinal damage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Chao-Peng; Yao, Jin; Tao, Zhi-Fu

Highlights: •UVB irradiation induces RPE autophagy. •EGCG treatment represses UVB-mediated autophagy. •EGCG regulates UVB-mediated autophagy through mTOR signaling pathway. •EGCG sensitizes RPE cells to UVB-induced damage in an autophagy-dependent manner. -- Abstract: Autophagy is an intracellular catabolic process involved in protein and organelle degradation via the lysosomal pathway that has been linked in the pathogenesis of age-related macular degeneration (AMD). UVB irradiation-mediated degeneration of the macular retinal pigment epithelial (RPE) cells is an important hallmark of AMD, which is along with the change in RPE autophagy. Thus, pharmacological manipulation of RPE autophagy may offer an alternative therapeutic target in AMD.more » Here, we found that epigallocatechin-3-gallate (EGCG), a polyphenolic compound from green tea, plays a regulatory role in UVB irradiation-induced autophagy in RPE cells. UVB irradiation results in a marked increase in the amount of LC3-II protein in a dose-dependent manner. EGCG administration leads to a significant reduction in the formation of LC3-II and autophagosomes. mTOR signaling activation is required for EGCG-induced LC3-II formation, as evidenced by the fact that EGCG-induced LC3-II formation is significantly impaired by rapamycin administration. Moreover, EGCG significantly alleviates the toxic effects of UVB irradiation on RPE cells in an autophagy-dependent manner. Collectively, our study reveals a novel role of EGCG in RPE autophagy. EGCG may be exploited as a potential therapeutic reagent for the treatment of pathological conditions associated with abnormal autophagy.« less

Protective Role of Mitochondrial Peroxiredoxin III against UVB-Induced Apoptosis of Epidermal Keratinocytes.

PubMed

Baek, Jin Young; Park, Sujin; Park, Jiyoung; Jang, Ji Yong; Wang, Su Bin; Kim, Sin Ri; Woo, Hyun Ae; Lim, Kyung Min; Chang, Tong-Shin

2017-06-01

UVB light induces generation of reactive oxygen species, ultimately leading to skin cell damage. Mitochondria are a major source of reactive oxygen species in UVB-irradiated skin cells, with increased levels of mitochondrial reactive oxygen species having been implicated in keratinocyte apoptosis. Peroxiredoxin III (PrxIII) is the most abundant and potent H 2 O 2 -removing enzyme in the mitochondria of most cell types. Here, the protective role of PrxIII against UVB-induced apoptosis of epidermal keratinocytes was investigated. Mitochondrial H 2 O 2 levels were differentiated from other types of ROS using mitochondria-specific fluorescent H 2 O 2 indicators. Upon UVB irradiation, PrxIII-knockdown HaCaT human keratinocytes and PrxIII-deficient (PrxIII -/- ) mouse primary keratinocytes exhibited enhanced accumulation of mitochondrial H 2 O 2 compared with PrxIII-expressing controls. Keratinocytes lacking PrxIII were subsequently sensitized to apoptosis through mitochondrial membrane potential loss, cardiolipin oxidation, cytochrome c release, and caspase activation. Increased UVB-induced epidermal tissue damage in PrxIII -/- mice was attributable to increased caspase-dependent keratinocyte apoptosis. Our findings show that mitochondrial H 2 O 2 is a key mediator in UVB-induced apoptosis of keratinocytes and that PrxIII plays a critical role in protecting epidermal keratinocytes against UVB-induced apoptosis through eliminating mitochondrial H 2 O 2 . These findings support the concept that reinforcing mitochondrial PrxIII defenses may help prevent UVB-induced skin damage such as inflammation, sunburn, and photoaging. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Photoprotective Properties of Isothiocyanate and Nitrile Glucosinolate Derivatives From Meadowfoam (Limnanthes alba) Against UVB Irradiation in Human Skin Equivalent.

PubMed

Carpenter, Evan L; Le, Mai N; Miranda, Cristobal L; Reed, Ralph L; Stevens, Jan F; Indra, Arup K; Ganguli-Indra, Gitali

2018-01-01

Exposure to ultraviolet B (UVB) irradiation of the skin leads to numerous dermatological concerns including skin cancer and accelerated aging. Natural product glucosinolate derivatives, like sulforaphane, have been shown to exhibit chemopreventive and photoprotective properties. In this study, we examined meadowfoam ( Limnanthes alba ) glucosinolate derivatives, 3-methoxybenzyl isothiocyanate (MBITC) and 3-methoxyphenyl acetonitrile (MPACN), for their activity in protecting against the consequences of UV exposure. To that end, we have exposed human primary epidermal keratinocytes (HPEKs) and 3D human skin reconstructed in vitro (EpiDerm TM FT-400) to UVB insult and investigated whether MBITC and MPACN treatment ameliorated the harmful effects of UVB damage. Activity was determined by the compounds' efficacy in counteracting UVB-induced DNA damage, matrix-metalloproteinase (MMP) expression, and proliferation. We found that in monolayer cultures of HPEK, MBITC and MPACN did not protect against a UVB-induced loss in proliferation and MBITC itself inhibited cell proliferation. However, in human reconstructed skin-equivalents, MBITC and MPACN decrease epidermal cyclobutane pyrimidine dimers (CPDs) and significantly reduce total phosphorylated γH2A.X levels. Both MBITC and MPACN inhibit UVB-induced MMP-1 and MMP-3 expression indicating their role to prevent photoaging. Both compounds, and MPACN in particular, showed activity against UVB-induced proliferation as indicated by fewer epidermal PCNA+ cells and prevented UVB-induced hyperplasia as determined by a reduction in reconstructed skin epidermal thickness (ET). These data demonstrate that MBITC and MPACN exhibit promising anti-photocarcinogenic and anti-photoaging properties in the skin microenvironment and could be used for therapeutic interventions.

Comparative analysis of the relative potential of silver, Zinc-oxide and titanium-dioxide nanoparticles against UVB-induced DNA damage for the prevention of skin carcinogenesis.

PubMed

Tyagi, Nikhil; Srivastava, Sanjeev K; Arora, Sumit; Omar, Yousef; Ijaz, Zohaib Mohammad; Al-Ghadhban, Ahmed; Deshmukh, Sachin K; Carter, James E; Singh, Ajay P; Singh, Seema

2016-12-01

Sunscreen formulations containing UVB filters, such as Zinc-oxide (ZnO) and titanium-dioxide (TiO 2 ) nanoparticles (NPs) have been developed to limit the exposure of human skin to UV-radiations. Unfortunately, these UVB protective agents have failed in controlling the skin cancer incidence. We recently demonstrated that silver nanoparticles (Ag-NPs) could serve as novel protective agents against UVB-radiations. Here our goal was to perform comparative analysis of direct and indirect UVB-protection efficacy of ZnO-, TiO 2 - and Ag-NPs. Sun-protection-factor calculated based on their UVB-reflective/absorption abilities was the highest for TiO 2 -NPs followed by Ag- and ZnO-NPs. This was further confirmed by studying indirect protection of UVB radiation-induced death of HaCaT cells. However, only Ag-NPs were active in protecting HaCaT cells against direct UVB-induced DNA-damage by repairing bulky-DNA lesions through nucleotide-excision-repair mechanism. Moreover, Ag-NPs were also effective in protecting HaCaT cells from UVB-induced oxidative DNA damage by enhancing SOD/CAT/GPx activity. In contrast, ZnO- and TiO 2 -NPs not only failed in providing any direct protection from DNA-damage, but rather enhanced oxidative DNA-damage by increasing ROS production. Together, these findings raise concerns about safety of ZnO- and TiO 2 -NPs and establish superior protective efficacy of Ag-NPs. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Silicon nanoparticles more effectively alleviated UV-B stress than silicon in wheat (Triticum aestivum) seedlings.

PubMed

Tripathi, Durgesh Kumar; Singh, Swati; Singh, Vijay Pratap; Prasad, Sheo Mohan; Dubey, Nawal Kishore; Chauhan, Devendra Kumar

2017-01-01

The role of silicon (Si) in alleviating biotic as well as abiotic stresses is well known. However, the potential of silicon nanoparticle (SiNP) in regulating abiotic stress and associated mechanisms have not yet been explored. Therefore, in the present study hydroponic experiments were conducted to investigate whether Si or SiNp are more effective in the regulation of UV-B stress. UV-B (ambient and enhanced) radiation caused adverse effect on growth of wheat (Triticum aestivum) seedlings, which was accompanied by declined photosynthetic performance and altered vital leaf structures. Levels of superoxide radical and H 2 O 2 were enhanced by UV-B as also evident from their histochemical stainings, which was accompanied by increased lipid peroxidation (LPO) and electrolyte leakage. Activities of superoxide dismutase and ascorbate peroxidase were inhibited by UV-B while catalase and guaiacol peroxidase, and all non-enzymatic antioxidants were stimulated by UV-B. Although, nitric oxide (NO) content was increased at all tested combinations, but its maximum content was observed under SiNps together with UV-B enhanced treatment. Pre-additions of SiNp as well as Si protected wheat seedlings against UV-B by regulating oxidative stress through enhanced antioxidants. Data indicate that SiNp might have protected wheat seedlings through NO-mediated triggering of antioxidant defense system, which subsequently counterbalance reactive oxygen species-induced damage to photosynthesis. Further, SiNp appear to be more effective in reducing UV-B stress than Si, which is related to its greater availability to wheat seedlings. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Isolation of a novel UVB-tolerant rice mutant obtained by exposure to carbon-ion beams.

PubMed

Takano, Nao; Takahashi, Yuko; Yamamoto, Mitsuru; Teranishi, Mika; Yamaguchi, Hiroko; Sakamoto, Ayako N; Hase, Yoshihiro; Fujisawa, Hiroko; Wu, Jianzhong; Matsumoto, Takashi; Toki, Seiichi; Hidema, Jun

2013-07-01

UVB radiation suppresses photosynthesis and protein biosynthesis in plants, which in turn decreases growth and productivity. Here, an ultraviolet-B (UVB)-tolerant rice mutant, utr319 (UV Tolerant Rice 319), was isolated from a mutagenized population derived from 2500 M1 seeds (of the UVB-resistant cultivar 'Sasanishiki') that were exposed to carbon ions. The utr319 mutant was more tolerant to UVB than the wild type. Neither the levels of UVB-induced cyclobutane pyrimidine dimers (CPDs) or (6-4) pyrimidine-pyrimidone photodimers [(6-4) photoproducts], nor the repair of CPDs or (6-4) photoproducts, was altered in the utr319 mutant. Thus, the utr319 mutant may be impaired in the production of a previously unidentified factor that confers UVB tolerance. To identify the mutated region in the utr319 mutant, microarray-based comparative genomic hybridization analysis was performed. Two adjacent genes on chromosome 7, Os07g0264900 and Os07g0265100, were predicted to represent the mutant allele. Sequence analysis of the chromosome region in utr319 revealed a deletion of 45 419 bp. RNAi analysis indicated that Os07g0265100 is most likely the mutated gene. Database analysis indicated that the Os07g0265100 gene, UTR319, encodes a putative protein with unknown characteristics or function. In addition, the homologs of UTR319 are conserved only among land plants. Therefore, utr319 is a novel UVB-tolerant rice mutant and UTR319 may be crucial for the determination of UVB sensitivity in rice, although the function of UTR319 has not yet been determined.

Glucose transporter member 1 is involved in UVB-induced epidermal hyperplasia by enhancing proliferation in epidermal keratinocytes.

PubMed

Tochio, Takumi; Tanaka, Hiroshi; Nakata, Satoru

2013-03-01

Glucose transporter member 1 (GLUT-1) is one of the major facilitated glucose transporters and contributes to the promotion of keratinocyte proliferation in psoriasis and carcinogenic lesions. In this study, we postulate that GLUT-1 is involved in ultraviolet B (UVB)-induced epidermal hyperplasia. The purpose of this study is to investigate the possible role of GLUT-1 in UVB-induced hyperplasia. The effects of UVB on GLUT-1 expression levels were investigated in in vitro and in vivo studies. In addition, the involvement of epidermal growth factor (EGF) and hypoxia inducible factor-1 alpha (HIF-1α), transcriptional factors for GLUT-1, in GLUT-1-related events were investigated. GLUT-1 mRNA and its protein levels were markedly increased by UVB irradiation in HaCaT cells. In in vivo studies, a strong immunofluorescence signal of GLUT-1 was clearly observed around the basal layer of the epidermis, which proliferated excessively by UVB irradiation. In HaCaT cells, EGF mRNA and its protein levels were markedly increased by UVB irradiation, and then the GLUT-1 mRNA level was significantly increased by treatment with EGF. Additionally, the upregulation of GLUT-1 by both UVB irradiation and treatment with EGF was significantly suppressed by transfection with HIF-1α siRNA. We conclude that GLUT-1 is involved in UVB-induced epidermal hyperplasia by enhancing proliferation of epidermal basal cells, and the GLUT-1-related event might be regulated by an increase in HIF-1α stimulated by EGF. © 2013 The International Society of Dermatology.

Protective effect of 4-coumaric acid from UVB ray damage in the rabbit eye.

PubMed

Lodovici, Maura; Caldini, Silvia; Morbidelli, Lucia; Akpan, Victor; Ziche, Marina; Dolara, Piero

2009-01-08

UV-induced oxidation damage seems to play a major role in a number of specific pathological conditions of intraocular tissues, such as cataract formation and retinal degeneration. Therefore, antioxidant and/or scavenger compounds might protect the eyes from UV-induced cellular damage. We previously reported that 4-coumaric acid (4-CA) is able to protect rabbit corneal-derived cells (SIRC) from UVB-induced oxidation damage. In this study we evaluated the protective effect of 4-CA against UVB-induced cell damage in rabbit cornea in vivo. Twelve male New Zealand albino rabbits were used; four rabbits were used as a control and received vehicle in one eye and 4-CA acid in the contralateral eye; eight rabbits were exposed to UVB rays (79.2mJ/cm(2)) and three days before to UV exposure each animal received 1 drop/day of vehicle in one eye and 1 drop/day of vehicle containing 4-CA (164ng) in the contralateral eye. Corneal and sclera tissues were removed and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) levels were measured. Superoxide dismutase (SOD) and xanthine oxidase (XO) activities were determined in aqueous humour. UVB-induced vessel hyper-reactivity was strongly reduced at 4 and 24h after UVB exposure after local treatment with 4-CA, 8-oxodGuo levels, a marker of oxidative DNA damage, were significantly increased (P<0.05) in sclera and cornea by UVB irradiation, but when 4-CA was administered to the conjunctiva in a buffered solution once a day for 3d before and 6d after UVB exposure, levels of 8-oxodGuo were similar to controls and significantly reduced (P<0.05) compared to UVB-treated corneas. XO activity in the aqueous humour was significantly increased. The administration of 4-CA for 3d before and 6d after UVB irradiation induced a small but significant (P<0.05) reduction of XO compared with control eyes. Our results indicate that the administration of 4-CA protects eye tissues, thus reducing the harmful effect of UVB radiation at low concentration, probably through its free radical scavenging and antioxidant properties. Therefore, 4-CA may be useful in protecting the eye from free radical damage following UVB exposure from sunlight, UV lamps and welding torches.

Human psychophysics and rodent spinal neurones exhibit peripheral and central mechanisms of inflammatory pain in the UVB and UVB heat rekindling models.

PubMed

O'Neill, Jessica; Sikandar, Shafaq; McMahon, Stephen B; Dickenson, Anthony H

2015-09-01

Translational research is key to bridging the gaps between preclinical findings and the patients, and a translational model of inflammatory pain will ideally induce both peripheral and central sensitisation, more effectively mimicking clinical pathophysiology in some chronic inflammatory conditions. We conducted a parallel investigation of two models of inflammatory pain, using ultraviolet B (UVB) irradiation alone and UVB irradiation with heat rekindling. We used rodent electrophysiology and human quantitative sensory testing to characterise nociceptive processing in the peripheral and central nervous systems in both models. In both species, UVB irradiation produces peripheral sensitisation measured as augmented evoked activity of rat dorsal horn neurones and increased perceptual responses of human subjects to mechanical and thermal stimuli. In both species, UVB with heat rekindling produces central sensitisation. UVB irradiation alone and UVB with heat rekindling are translational models of inflammation that produce peripheral and central sensitisation, respectively. The predictive value of laboratory models for human pain processing is crucial for improving translational research. The discrepancy between peripheral and central mechanisms of pain is an important consideration for drug targets, and here we describe two models of inflammatory pain that involve ultraviolet B (UVB) irradiation, which can employ peripheral and central sensitisation to produce mechanical and thermal hyperalgesia in rats and humans. We use electrophysiology in rats to measure the mechanically- and thermally-evoked activity of rat spinal neurones and quantitative sensory testing to assess human psychophysical responses to mechanical and thermal stimulation in a model of UVB irradiation and in a model of UVB irradiation with heat rekindling. Our results demonstrate peripheral sensitisation in both species driven by UVB irradiation, with a clear mechanical and thermal hypersensitivity of rat dorsal horn neurones and enhanced perceptual responses of human subjects to both mechanical and thermal stimulation. Additional heat rekindling produces markers of central sensitisation in both species, including enhanced receptive field sizes. Importantly, we also showed a correlation in the evoked activity of rat spinal neurones to human thermal pain thresholds. The parallel results in rats and humans validate the translational use of both models and the potential for such models for preclinical assessment of prospective analgesics in inflammatory pain states. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

Objective validation of central sensitization in the rat UVB and heat rekindling model

PubMed Central

Weerasinghe, NS; Lumb, BM; Apps, R; Koutsikou, S; Murrell, JC

2014-01-01

Background The UVB and heat rekindling (UVB/HR) model shows potential as a translatable inflammatory pain model. However, the occurrence of central sensitization in this model, a fundamental mechanism underlying chronic pain, has been debated. Face, construct and predictive validity are key requisites of animal models; electromyogram (EMG) recordings were utilized to objectively demonstrate validity of the rat UVB/HR model. Methods The UVB/HR model was induced on the heel of the hind paw under anaesthesia. Mechanical withdrawal thresholds (MWTs) were obtained from biceps femoris EMG responses to a gradually increasing pinch at the mid hind paw region under alfaxalone anaesthesia, 96 h after UVB irradiation. MWT was compared between UVB/HR and SHAM-treated rats (anaesthetic only). Underlying central mechanisms in the model were pharmacologically validated by MWT measurement following intrathecal N-methyl-d-aspartate (NMDA) receptor antagonist, MK-801, or saline. Results Secondary hyperalgesia was confirmed by a significantly lower pre-drug MWT {mean [±standard error of the mean (SEM)]} in UVB/HR [56.3 (±2.1) g/mm2, n = 15] compared with SHAM-treated rats [69.3 (±2.9) g/mm2, n = 8], confirming face validity of the model. Predictive validity was demonstrated by the attenuation of secondary hyperalgesia by MK-801, where mean (±SEM) MWT was significantly higher [77.2 (±5.9) g/mm2 n = 7] in comparison with pre-drug [57.8 (±3.5) g/mm2 n = 7] and saline [57.0 (±3.2) g/mm2 n = 8] at peak drug effect. The occurrence of central sensitization confirmed construct validity of the UVB/HR model. Conclusions This study used objective outcome measures of secondary hyperalgesia to validate the rat UVB/HR model as a translational model of inflammatory pain. What's already known about this topic? Most current animal chronic pain models lack translatability to human subjects. Primary hyperalgesia is an established feature of the UVB/heat rekindling inflammatory pain model in rodents and humans, but the presence of secondary hyperalgesia, a hallmark feature of central sensitization and thus chronic pain, is contentious. What does this study add? Secondary hyperalgesia was demonstrated in the rat UVB/heat rekindling model using an objective outcome measure (electromyogram), overcoming the subjective limitations of previous behavioural studies. PMID:24590815

Identification of microRNA-mRNA functional interactions in UVB-induced senescence of human diploid fibroblasts

PubMed Central

2013-01-01

Background Cellular senescence can be induced by a variety of extrinsic stimuli, and sustained exposure to sunlight is a key factor in photoaging of the skin. Accordingly, irradiation of skin fibroblasts by UVB light triggers cellular senescence, which is thought to contribute to extrinsic skin aging, although molecular mechanisms are incompletely understood. Here, we addressed molecular mechanisms underlying UVB induced senescence of human diploid fibroblasts. Results We observed a parallel activation of the p53/p21WAF1 and p16INK4a/pRb pathways. Using genome-wide transcriptome analysis, we identified a transcriptional signature of UVB-induced senescence that was conserved in three independent strains of human diploid fibroblasts (HDF) from skin. In parallel, a comprehensive screen for microRNAs regulated during UVB-induced senescence was performed which identified five microRNAs that are significantly regulated during the process. Bioinformatic analysis of miRNA-mRNA networks was performed to identify new functional mRNA targets with high confidence for miR-15a, miR-20a, miR-20b, miR-93, and miR-101. Already known targets of these miRNAs were identified in each case, validating the approach. Several new targets were identified for all of these miRNAs, with the potential to provide new insight in the process of UVB-induced senescence at a genome-wide level. Subsequent analysis was focused on miR-101 and its putative target gene Ezh2. We confirmed that Ezh2 is regulated by miR-101 in human fibroblasts, and found that both overexpression of miR-101 and downregulation of Ezh2 independently induce senescence in the absence of UVB irradiation. However, the downregulation of miR-101 was not sufficient to block the phenotype of UVB-induced senescence, suggesting that other UVB-induced processes induce the senescence response in a pathway redundant with upregulation of miR-101. Conclusion We performed a comprehensive screen for UVB-regulated microRNAs in human diploid fibroblasts, and identified a network of miRNA-mRNA interactions mediating UVB-induced senescence. In addition, miR-101 and Ezh2 were identified as key players in UVB-induced senescence of HDF. PMID:23557329

Genomic fragmentation and extrachromosomal telomeric repeats impact assessment of telomere length in human spermatozoa: quantitative experiments and systematic review.

PubMed

Kurjanowicz, P; Moskovtsev, S; Librach, C

2017-11-01

Can differences in DNA isolation alter assessment of sperm telomere length (spTL) and do they account for conflicting results in the literature on spTL and male fertility? DNA isolation methods preferentially include or exclude short, extrachromosomal (EC) telomere-specific sequences that alter spTL measurements, and are responsible for a proportion of the disparity observed between investigations. The relationship between spTL and male fertility has become an active area of research. The results across investigations, however, have been discordant, generating a need to critically evaluate the existing body of knowledge to guide future investigations. Quantitative experiments determined the effect of DNA isolation on the integrity of sperm DNA and measures of spTL, while a systematic analysis of the current literature evaluated the effect of DNA isolation and study design on experimental outcomes. Two DNA isolation methods were compared: Genomic Tips which isolate 'High Molecular Weight' (HMW) DNA exclusively, and QIAamp® DNA Mini which isolates 'Total' genomic DNA irrespective of size. DNA quality was assessed via field inversion gel electrophoresis (FIGE) and spTL was measured via terminal restriction fragment analysis. In addition, major databases in medicine, health and the life sciences were subject to a targeted search, and results were independently screened according to defined exclusion/inclusion criterion. Findings from primary articles were analyzed for concordance and study designs were compared across six moderator variables (sample size, participant age, fertility status, semen fraction, telomere population and type of analysis). HMW DNA spTL was significantly longer than spTL measured from total DNA (P < 0.01), indicating that Total DNA contained short, EC telomeric repeats that shifted downstream assessment towards shorter spTL. HMW DNA spTL reflected the length of intact, chromosomal telomeres. Major findings on spTL showed the greatest concordance amongst studies that implemented HMW DNA isolation prior to spTL assessment. Studies that utilized Total DNA varied in concordance, but outcomes were similar if (i) a comparative analysis was applied or (ii) a sample size threshold of 81 was achieved for correlative analysis. Chromosomal and EC telomeric DNA were distinguished based on outcomes of HMW DNA isolation and size. Further experiments are required to determine the nature and function of these two types of telomeric sequences. This study reveals a dramatic impact of upstream DNA processing and study design on measurements of spTL, which accounts for conflicting results in the literature. Future assessments of spTL should incorporate independent detection of chromosomal and EC telomeric DNA and specific experimental planning. This study was funded by CReATe Fertility Centre, Toronto, Ontario, Canada. The authors have declared no conflict of interest. N/A. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Ultraviolet-B- and ozone-induced biochemical changes in antioxidant enzymes of Arabidopsis thaliana.

PubMed Central

Rao, M V; Paliyath, G; Ormrod, D P

1996-01-01

Earlier studies with Arabidopsis thaliana exposed to ultraviolet B (UV-B) and ozone (O3) have indicated the differential responses of superoxide dismutase and glutathione reductase. In this study, we have investigated whether A. thaliana genotype Landsberg erecta and its flavonoid-deficient mutant transparent testa (tt5) is capable of metabolizing UV-B- and O3-induced activated oxygen species by invoking similar antioxidant enzymes. UV-B exposure preferentially enhanced guaiacol-peroxidases, ascorbate peroxidase, and peroxidases specific to coniferyl alcohol and modified the substrate affinity of ascorbate peroxidase. O3 exposure enhanced superoxide dismutase, peroxidases, glutathione reductase, and ascorbate peroxidase to a similar degree and modified the substrate affinity of both glutathione reductase and ascorbate peroxidase. Both UV-B and O3 exposure enhanced similar Cu,Zn-superoxide dismutase isoforms. New isoforms of peroxidases and ascorbate peroxidase were synthesized in tt5 plants irradiated with UV-B. UV-B radiation, in contrast to O3, enhanced the activated oxygen species by increasing membrane-localized NADPH-oxidase activity and decreasing catalase activities. These results collectively suggest that (a) UV-B exposure preferentially induces peroxidase-related enzymes, whereas O3 exposure invokes the enzymes of superoxide dismutase/ascorbate-glutathione cycle, and (b) in contrast to O3, UV-B exposure generated activated oxygen species by increasing NADPH-oxidase activity. PMID:8587977

Biochemical traits and proteomic changes in postharvest flowers of medicinal chrysanthemum exposed to enhanced UV-B radiation.

PubMed

Yao, Xiaoqin; Chu, Jian-Zhou; Ma, Chun-Hui; Si, Chao; Li, Ji-Gang; Shi, Xiao-Fei; Liu, Chao-Nan

2015-08-01

The article studied UV-B effects on biochemical traits and proteomic changes in postharvest flowers of medicinal chrysanthemum. The experiment about UV-B effects on biochemical traits in flowers included six levels of UV-B treatments (0 (UV0), 50 (UV50), 200 (UV200), 400 (UV400), 600 (UV600) and 800 (UV800) μWcm(-2)). UV400, UV600 and UV800 treatments significantly increased the contents of hydrogen peroxide, malondialdehyde and UV-B absorbing compounds, and the activity of phenylalanine ammonia lyase enzyme over the control. The contents of chlorogenic acid and flavone in flowers were significantly increased by UV-B treatments (except for UV50 and UV800). Two-dimensional gel electrophoresis was utilized to analyze proteomic changes in flowers with or without UV-B radiation. Results indicated that 43 protein spots (>1.5-fold difference in volume) were detected, including 19 spots with a decreasing trend and 24 spots with an increasing trend, and 19 differentially expressed protein spots were successfully indentified by MALDI-TOF MS. The indentified proteins were classified based on functions, the most of which were involved in photosynthesis, respiration, protein biosynthesis and degradation and defence. An overall assessment using biochemical and differential proteomic data revealed that UV-B radiation could affect biochemical reaction and promote secondary metabolism processes in postharvest flowers. Copyright © 2015 Elsevier B.V. All rights reserved.

The effects of UV-B radiation intensity on biochemical parameters and active ingredients in flowers of Qi chrysanthemum and Huai chrysanthemum.

PubMed

Yao, Xiao-Qin; Chu, Jian-Zhou; He, Xue-Li; Si, Chao

2014-01-01

The article studied UV-B effects on biochemical parameters and active ingredients in flowers of Qi chrysanthemum and Huai chrysanthemum during the bud stage. The experiment included four UV-B radiation levels (CK, ambient UV-B; T1, T2 and T3 indicated a 5%, 10% and 15% increase in ambient UV-BBE, respectively) to determine the optimal UV-B radiation intensity in regulating active ingredients level in flowers of two chrysanthemum varieties. Flower dry weight of two cultivars was not affected by UV-B radiation under experimental conditions reported here. UV-B treatments significantly increased the rate of superoxide radical production, hydrogen peroxide (H2O2) (except for T1) and malondialdehyde concentration in flowers of Huai chrysanthemum and H2O2 concentration in flowers of Qi chrysanthemum. T2 and T3 treatments induced a significant increase in phenylalanine ammonia lyase enzyme (PAL) activity, anthocyanins, proline, ascorbic acid, chlorogenic acid and flavone content in flowers of two chrysanthemum varieties, and there were no significant differences in PAL activity, ascorbic acid, flavone and chlorogenic acid content between the two treatments. These results indicated that appropriate UV-B radiation intensity did not result in the decrease in flower yield, and could regulate PAL activity and increase active ingredients content in flowers of two chrysanthemum varieties. © 2014 The American Society of Photobiology.

A small increase in UV-B increases the susceptibility of tadpoles to predation

PubMed Central

Alton, Lesley A.; Wilson, Robbie S.; Franklin, Craig E.

2011-01-01

Increased ultraviolet-B (UV-B) radiation as a consequence of ozone depletion is one of the many potential drivers of ongoing global amphibian declines. Both alone and in combination with other environmental stressors, UV-B is known to have detrimental effects on the early life stages of amphibians, but our understanding of the fitness consequences of these effects remains superficial. We examined the independent and interactive effects of UV-B and predatory chemical cues (PCC) on a suite of traits of Limnodynastes peronii embryos and tadpoles, and assessed tadpole survival time in a predator environment to evaluate the potential fitness consequences. Exposure to a 3 to 6 per cent increase in UV-B, which is comparable to changes in terrestrial UV-B associated with ozone depletion, had no effect on any of the traits measured, except survival time in a predator environment, which was reduced by 22 to 28 per cent. Exposure to PCC caused tadpoles to hatch earlier, have reduced hatching success, have improved locomotor performance and survive for longer in a predator environment, but had no effect on tadpole survival, behaviour or morphology. Simultaneous exposure to UV-B and PCC resulted in no interactive effects. These findings demonstrate that increased UV-B has the potential to reduce tadpole fitness, while exposure to PCCs improves their fitness. PMID:21270039

Effect of Thai banana (Musa AA group) in reducing accumulation of oxidation end products in UVB-irradiated mouse skin.

PubMed

Leerach, Nontaphat; Yakaew, Swanya; Phimnuan, Preeyawass; Soimee, Wichuda; Nakyai, Wongnapa; Luangbudnark, Witoo; Viyoch, Jarupa

2017-03-01

Chronic UVB exposure causes skin disorders and cancer through DNA strand breaks and oxidation of numerous functional groups of proteins and lipids in the skin. In this study, we investigated the effects of Thai banana (Musa AA group, "Khai," and Musa ABB group, "Namwa") on the prevention of UVB-induced skin damage when fed to male ICR mice. Mice were orally fed banana (Khai or Namwa) fruit pulps at dose of 1mg/g body weight/day for 12weeks. The shaved backs of the mice were irradiated with UVB for 12weeks. The intensity dose of UVB-exposure was increased from 54mJ/cm 2 /exposure at week 1 to 126mJ/cm 2 /exposure at week 12. A significant increase in skin thickness, lipid peroxidation, protein oxidation end products, and expression of MMP-1 was observed in UVB-irradiated mouse skin. A reduction in the accumulation of oxidation end products was found in the skin of UVB-irradiated mice receiving Khai. This occurred in conjunction with a reduction in MMP-1 expression, inhibition of epidermal thickening, and induction of γ-GCS expression. The dietary intake of Khai prevented skin damage from chronic UVB exposure by increased γ-GCS expression and reduced oxidation end products included carbonyls, malondialdehyde and 4-hydroxynonenal. Copyright © 2017 Elsevier B.V. All rights reserved.

Rapid repair of UVA-induced oxidized purines and persistence of UVB-induced dipyrimidine lesions determine the mutagenicity of sunlight in mouse cells

PubMed Central

Besaratinia, Ahmad; Kim, Sang-in; Pfeifer, Gerd P.

2009-01-01

Despite the predominance of UVA relative to UVB in terrestrial sunlight, solar mutagenesis in humans and rodents is characterized by mutations specific for UVB. We have investigated the kinetics of repair of UVA- and UVB-induced DNA lesions in relation to mutagenicity in transgenic mouse fibroblasts irradiated with equilethal doses of UVA and UVB in comparison to SSL. We have also analyzed mutagenesis-derived carcinogenesis in sunlight-associated human skin cancers by compiling the published data on mutation types found in crucial genes in non-melanoma and melanoma skin cancers. Here, we demonstrate a resistance to repair of UVB-induced CPDs together with rapid removal of UVA-induced oxidized purines in the genome overall and in the cII transgene of SSL-irradiated cells. The spectra of mutation induced by both UVB- and SSL-irradiation in this experimental system are characterized by significant increases in relative frequency of C to T transitions at dipyrimidines, which are the established signature mutation of CPDs. This type of mutation is also the predominant mutation found in human non-melanoma and melanoma tumor samples in the TP53, CDKN2, PTCH, and protein kinase genes. The prevailing role of UVB over UVA in solar mutagenesis in our test system can be ascribed to different kinetics of repair for lesions induced by the respective UV-irradiation. PMID:18326785

Responses of photosynthetic properties and chloroplast ultrastructure of Bryum argenteum from a desert biological soil crust to elevated ultraviolet-B radiation.

PubMed

Hui, Rong; Li, Xinrong; Chen, Cuiyun; Zhao, Xin; Jia, Rongliang; Liu, Lichao; Wei, Yongping

2013-04-01

Our understanding of plant responses to enhanced ultraviolet-B (UV-B) radiation has improved over recent decades. However, research on cryptogams is scarce and it remains controversial whether UV-B radiation causes changes in physiology related to photosynthesis. To investigate the effects of supplementary UV-B radiation on photosynthesis and chloroplast ultrastructure in Bryum argenteum Hedw., specimens were cultured for 10 days under four UV-B treatments (2.75, 3.08, 3.25 and 3.41 W m(-2) ), simulating depletion of 0% (control), 6%, 9% and 12% of stratospheric ozone at the latitude of Shapotou, a temperate desert area of northwest China. Analyses showed malondialdehyde content significantly increased, whereas chlorophyll (Chl) fluorescence parameters and Chl contents decreased with increased UV-B intensity. These results corresponded with changes in thylakoid protein complexes and chloroplast ultrastructure. Overall, enhanced UV-B radiation leads to significant decreases in photosynthetic function and serious destruction of the chloroplast ultrastructure of B. argenteum. The degree of negative influences increased with the intensity of UV-B radiation. These results may not only provide a potential mechanism for supplemental UV-B effects on photosynthesis of moss crust, but also establish a theoretical basis for further studies of adaptation and response mechanisms of desert ecosystems under future ozone depletion. Copyright © Physiologia Plantarum 2012.

Inhibition of ultraviolet-B epidermal ornithine decarboxylase induction and skin carcinogenesis in hairless mice by topical indomethacin and triamcinolone acetonide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lowe, N.J.; Connor, M.J.; Breeding, J.

1982-10-01

Modulation of ultraviolet-B (UVB) skin carcinogenesis by topical treatment with two antiinflammatory drugs expected to have different mechanisms of action has been studied in the hairless mouse. Indomethacin is a nonsteroidal antiinflammatory agent which may act by inhibiting prostaglandin biosynthesis. Triamcinolone acetonide is a steroidal antiinflammatory agent. Both of these drugs inhibited the induction of epidermal ornithine decarboxylase by UVB when applied topically in a acetone vehicle. A UVB skin tumor study was designed. Groups of mice were irradiated daily with UVB for 20 days, each mouse receiving a total of 17.1 kJ UVB per sq m. Group 1 wasmore » treated with acetone immediately after each irradiation; Group 2 received 700 nmol indomethacin in acetone immediately after each irradiation; Group 3 received 14.4 nmol triamcinolone acetonide in acetone immediately after each irradiation. Mice were killed after 52 weeks, and the tumors were excised and examined histologically. Both topical indomethacin and topical triamcinolone acetonide were effective in reducing the incidence and size of the skin tumors induced by UVB. This evidence supports the hypothesis that the induction of ornithine decarboxylase may be a critical component of UVB skin carcinogenesis and that inhibition of ornithine decarboxylase induction can be used as a screen for agents which will inhibit UVB skin carcinogenesis.« less

p-Coumaric Acid Attenuates UVB-Induced Release of Stratifin from Keratinocytes and Indirectly Regulates Matrix Metalloproteinase 1 Release from Fibroblasts

PubMed Central

Seok, Jin Kyung

2015-01-01

Ultraviolet (UV) radiation-induced loss of dermal extracellular matrix is associated with skin photoaging. Recent studies demonstrated that keratinocyte-releasable stratifin (SFN) plays a critical role in skin collagen metabolism by inducing matrix metalloproteinase 1 (MMP1) expression in target fibroblasts. In the present study, we examined whether SFN released from UVB-irradiated epidermal keratinocytes increases MMP1 release from dermal fibroblasts, and whether these events are affected by p-coumaric acid (p-CA), a natural phenolic compound with UVB-shielding and antioxidant properties. HaCaT cells were exposed to UVB in the absence and presence of p-CA, and the conditioned medium was used to stimulate fibroblasts in medium transfer experiments. The cells and media were analyzed to determine the expressions/releases of SFN and MMP1. UVB exposure increased SFN release from keratinocytes into the medium. The conditioned medium of UVB-irradiated keratinocytes increased MMP1 release from fibroblasts. The depletion of SFN using a siRNA rendered the conditioned medium of UVB-irradiated keratinocytes ineffective at stimulating fibroblasts to release MMP1. p-CA mitigated UVB-induced SFN expression in keratinocytes, and attenuated the MMP1 release by fibroblasts in medium transfer experiments. In conclusion, the present study demonstrated that the use of UV absorbers such as p-CA would reduce UV-induced SFN-centered signaling events involved in skin photoaging. PMID:25954129

p-Coumaric Acid Attenuates UVB-Induced Release of Stratifin from Keratinocytes and Indirectly Regulates Matrix Metalloproteinase 1 Release from Fibroblasts.

PubMed

Seok, Jin Kyung; Boo, Yong Chool

2015-05-01

Ultraviolet (UV) radiation-induced loss of dermal extracellular matrix is associated with skin photoaging. Recent studies demonstrated that keratinocyte-releasable stratifin (SFN) plays a critical role in skin collagen metabolism by inducing matrix metalloproteinase 1 (MMP1) expression in target fibroblasts. In the present study, we examined whether SFN released from UVB-irradiated epidermal keratinocytes increases MMP1 release from dermal fibroblasts, and whether these events are affected by p-coumaric acid (p-CA), a natural phenolic compound with UVB-shielding and antioxidant properties. HaCaT cells were exposed to UVB in the absence and presence of p-CA, and the conditioned medium was used to stimulate fibroblasts in medium transfer experiments. The cells and media were analyzed to determine the expressions/releases of SFN and MMP1. UVB exposure increased SFN release from keratinocytes into the medium. The conditioned medium of UVB-irradiated keratinocytes increased MMP1 release from fibroblasts. The depletion of SFN using a siRNA rendered the conditioned medium of UVB-irradiated keratinocytes ineffective at stimulating fibroblasts to release MMP1. p-CA mitigated UVB-induced SFN expression in keratinocytes, and attenuated the MMP1 release by fibroblasts in medium transfer experiments. In conclusion, the present study demonstrated that the use of UV absorbers such as p-CA would reduce UV-induced SFN-centered signaling events involved in skin photoaging.

IKKα contributes to UVB-induced VEGF expression by regulating AP-1 transactivation

PubMed Central

Dong, Wen; Li, Yi; Gao, Ming; Hu, Meiru; Li, Xiaoguang; Mai, Sanyue; Guo, Ning; Yuan, Shengtao; Song, Lun

2012-01-01

Exposure to ultraviolet B (UVB) irradiation from sunlight induces the upregulation of VEGF, a potent angiogenic factor that is critical for mediating angiogenesis-associated photodamage. However, the molecular mechanisms related to UVB-induced VEGF expression have not been fully defined. Here, we demonstrate that one of the catalytic subunits of the IκB kinase complex (IKK), IKKα, plays a critical role in mediating UVB-induced VEGF expression in mouse embryonic fibroblasts (MEFs), which requires IKKα kinase activity but is independent of IKKβ, IKKγ and the transactivation of NF-κB. We further show that the transcriptional factor AP-1 functions as the downstream target of IKKα that is responsible for VEGF induction under UVB exposure. Both the accumulation of AP-1 component, c-Fos and the transactivation of AP-1 by UVB require the activated IKKα located within the nucleus. Moreover, nuclear IKKα can associate with c-Fos and recruit to the vegf promoter regions containing AP-1-responsive element and then trigger phosphorylation of the promoter-bound histone H3. Thus, our results have revealed a novel independent role for IKKα in controlling VEGF expression during the cellular UVB response by regulating the induction of the AP-1 component and phosphorylating histone H3 to facilitate AP-1 transactivation. Targeting IKKα shows promise for the prevention of UVB-induced angiogenesis and the associated photodamage. PMID:22169952

Protective effects of Aloe sterols against UVB-induced photoaging in hairless mice.

PubMed

Misawa, Eriko; Tanaka, Miyuki; Saito, Marie; Nabeshima, Kazumi; Yao, Ruiqing; Yamauchi, Kouji; Abe, Fumiaki; Yamamoto, Yuki; Furukawa, Fukumi

2017-03-01

Aloe vera is a traditional medical plant whose gel has been widely used in skin care. Previously, we have identified Aloe sterols from Aloe vera as active ingredients. This study investigated the protective effects of Aloe sterols without polysaccharides, against ultraviolet B (UVB)-induced skin photoaging in mice using Aloe vera gel extract (AVGE) obtained by supercritical fluid extraction. Aloe vera gel extract was supplemented in the diet (12 or 120 ppm), and HR-1 hairless mice were exposed to UVB irradiation for 7 weeks. Skin measurements and histological and analytical studies were performed. Repeated UVB irradiation induced rough wrinkling of skin with water content reduction and hyperkeratosis. AVGE administration resulted in the significant improvement of UVB-induced skin dryness, epidermal thickness, and wrinkle formation. The AVGE group also suppressed the degenerations of dermal collagen fibers and the appearance of cutaneous apoptosis cells induced by UVB. Furthermore, AVGE administration reduced the excess elevation of pro-inflammatory cytokines (IL-1β and TNF-α) and matrix metalloproteinases (MMP-2, MMP-9, MMP-12, and MMP-13) in UVB-exposed skin. The dietary ingestion of Aloe sterols protected against chronic UVB damage in mouse skin, and our results suggest that Aloe sterols may prevent skin photoaging through the anti-inflammation and MMP regulation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Angiotensin-converting enzyme inhibitor (enalapril maleate) accelerates recovery of mouse skin from UVB-induced wrinkles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsuura-Hachiya, Yuko; Arai, Koji Y.; Ozeki, Rieko

Highlights: •Angiotensin converting enzyme (ACE) increases in UVB-irradiated skin. •Administration of an ACE inhibitor improved UVB-induced skin wrinkle. •ACE inhibitor improved UVB-induced epidermal hypertrophy. •ACE inhibitor improved transepidermal water loss in the UVB-irradiated skin. -- Abstract: Angiotensin-converting enzyme (ACE) activity and angiotensin II signaling regulate cell proliferation, differentiation, and tissue remodeling, as well as blood pressure, while in skin, angiotensin II signaling is involved in wound healing, inflammation, and pathological scar formation. Therefore, we hypothesized that angiotensin II is also involved in photoaging of skin. In this study, we examined the effect of enalapril maleate, an ACE inhibitor, on recoverymore » of wrinkled skin of hairless mice exposed to long-term UVB irradiation. Immunohistochemical observation revealed that expression of ACE, angiotensin II, and angiotensin II type 1 (AT1) and type 2 (AT2) receptors in the skin was increased after UVB irradiation (3 times/week at increasing intensities for 8 weeks). Administration of enalapril maleate (5 times/week for 6 weeks, starting 1 week after 10-week irradiation) accelerated recovery from UVB-induced wrinkles, epidermal hyperplasia and epidermal barrier dysfunction, as compared with the vehicle control. Our results indicate that ACE and angiotensin II activity are involved in skin photoaging, and suggest that ACE inhibitor such as enalapril maleate may have potential for improvement of photoaged skin.« less

Association of Diet With Skin Histological Features in UV-B-Exposed Mice.

PubMed

Bhattacharyya, Tapan K; Hsia, Yvonne; Weeks, David M; Dixon, Tatiana K; Lepe, Jessica; Thomas, J Regan

2017-09-01

Long-term exposure to solar radiation produces deleterious photoaging of the skin. It is not known if diet can influence skin photoaging. To study the influence of a calorie-restricted diet and an obesity diet in mice exposed to long-term UV-B irradiation to assess if there is an association between diet and histopathological response to UV-B irradiation. In this animal model study in an academic setting, the dorsal skin of SKH1 hairless mice receiving normal, calorie-restricted, and obesity diets was exposed to UV-B irradiation 3 times a week for 10 weeks and were compared with corresponding controls. The mice were placed in the following groups, with 8 animals in each group: (1) intact control (C) with regular diet and no UV-B exposure, (2) intact control with UV-B exposure (CR), (3) calorie-restricted diet (CrC), (4) calorie-restricted diet with UV-B exposure (CrR), (5) obesity diet (OC), and (6) obesity diet with UV-B exposure (OR). The experiment was conducted during October through December 2013. Tissue processing and histological analysis were completed in 2016. Histomorphometric analysis was performed on paraffin-embedded skin sections stained by histological and immunohistochemical methods for estimation of epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, mast cells, dermal cellularity, and adipose layer ratio. Changes in wrinkles were noted. Hairless female mice (age range, 6-8 weeks) were obtained. With a normal diet, changes from UV-B irradiation occurred in epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, and mast cells, which were modestly influenced by an obesity diet. Calorie restriction influenced the skin in nonirradiated control animals, with higher values for most variables. After UV-B exposure in animals with calorie restriction, epidermal thickness was increased, but other variables were unaffected. Animals receiving the calorie-restricted diet lost weight when exposed to long-term UV-B irradiation. Wrinkles were reduced in the calorie-restricted control group and in UV-B-exposed animals who received the obesity diet. Dietary alterations seem to modify histopathological responses to UV-B exposure in the skin of hairless mice. NA.

Effects of UV-B radiation on leaf hair traits of invasive plants-Combining historical herbarium records with novel remote sensing data.

PubMed

Václavík, Tomáš; Beckmann, Michael; Cord, Anna F; Bindewald, Anja M

2017-01-01

Ultraviolet-B (UV-B) radiation is a key but under-researched environmental factor that initiates diverse responses in plants, potentially affecting their distribution. To date, only a few macroecological studies have examined adaptations of plant species to different levels of UV-B. Here, we combined herbarium specimens of Hieracium pilosella L. and Echium vulgare L. with a novel UV-B dataset to examine differences in leaf hair traits between the plants' native and alien ranges. We analysed scans of 336 herbarium specimens using standardized measurements of leaf area, hair density (both species) and hair length (H. pilosella only). While accounting for other bioclimatic variables (i.e. temperature, precipitation) and effects of herbivory, we examined whether UV-B exposure explains the variability and geographical distribution of these traits in the native (Northern Hemisphere) vs. the alien (Southern Hemisphere) range. UV-B explained the largest proportion of the variability and geographical distribution of hair length in H. pilosella (relative influence 67.1%), and hair density in E. vulgare (66.2%). Corresponding with higher UV-B, foliar hairs were 25% longer for H. pilosella and 25% denser for E. vulgare in records from the Southern as compared to those from the Northern Hemisphere. However, focusing on each hemisphere separately or controlling for its effect in a regression analysis, we found no apparent influence of UV-B radiation on hair traits. Thus, our findings did not confirm previous experimental studies which suggested that foliar hairs may respond to higher UV-B intensities, presumably offering protection against detrimental levels of radiation. We cannot rule out UV-B radiation as a possible driver because UV-B radiation was the only considered variable that differed substantially between the hemispheres, while bioclimatic conditions (e.g. temperature, precipitation) and other considered variables (herbivory damage, collection date) were at similar levels. However, given that either non-significant or inconclusive relationships were detected within hemispheres, alternative explanations of the differences in foliar hairs are more likely, including the effects of environment, genotypes or herbivory.

Protection against free radicals (UVB irradiation) of a water-soluble enzymatic extract from rice bran. Study using human keratinocyte monolayer and reconstructed human epidermis.

PubMed

Santa-María, C; Revilla, E; Miramontes, E; Bautista, J; García-Martínez, A; Romero, E; Carballo, M; Parrado, J

2010-01-01

The antioxidant capacity of a water-soluble enzymatic extract from rice bran (EERB) has been tested in two cell models: keratinocyte monolayers and human reconstructed epidermis. Cells were incubated in culture medium in presence of different amounts of EERB and were UVB irradiated. Cell population assessment (MTT assay) and MDA (malonaldehyde) production were evaluated. The EERB did not induce cytotoxic effect for concentrations inferior or equal to 100 microg/mL. Human keratinocyte monolayers were protected of irradiation preventing 33% the lipid peroxidation process at concentration of 10 microg/ml of EEBR. In reconstructed human epidermis, 100 microg/mL decreased lipid peroxidation process by 44% (p<0.01) with regards to irradiated negative control. This effect was comparable to that of vitamin E at 600 microg/mL. Our data indicate that EERB is potentially able to efficiently counteract UVB-induced response. The EERB, diluted at 10% with water has very good skin compatibility. This product showed a sun protection factor of 4.8+/-0.3. Thus we can propose EERB as a useful natural standardized extract in skin photoprotection with promising applications in the field of dermatology. Copyright 2009 Elsevier Ltd. All rights reserved.

The imprints of the high light and UV-B stresses in Oryza sativa L. 'Kanchana' seedlings are differentially modulated.

PubMed

Faseela, Parammal; Puthur, Jos T

2018-01-01

High light and ultraviolet-B radiation (UV-B) are generally considered to have negative impact on photosynthesis and plant growth. The present study evaluates the tolerance potential of three cultivars of Oryza sativa L. (Kanchana, Mattatriveni and Harsha) seedlings towards high light and UV-B stress on the basis of photosynthetic pigment degradation, chlorophyll a fluorescence parameters and rate of lipid peroxidation, expressed by malondialdehyde content. Surprisingly, it was revealed that Kanchana was the most sensitive cultivar towards high light and at the same time it was the most tolerant cultivar towards UV-B stress. This contrasting feature of Kanchana towards high light and UV-B tolerance was further studied by analyzing photosystem (PS) I and II activity, mitochondrial activity, chlorophyll a fluorescence transient, enzymatic and non-enzymatic antioxidant defense system. Due to the occurrence of more PS I and PSII damages, the inhibition of photochemical efficiency and emission of dissipated energy as heat or fluorescence per PSII reaction center was higher upon high light exposure than UV-B treatments in rice seedlings of Kanchana. The mitochondrial activity was also found to be drastically altered upon high light as compared to UV-B treatments. The UV-B induced accumulation of non-enzymatic antioxidants (proline, total phenolics, sugar and ascorbate) and enzymatic antioxidants (ascorbate peroxidase, guaiacol peroxidase, superoxide dismutase and glutathione reductase) in rice seedlings than those subjected to high light exposure afforded more efficient protection against UV-B radiation in rice seedlings. Our results proved that high tolerance of Kanchana towards UV-B than high light treatments, correlated linearly with the protected photosynthetic and mitochondrial machinery which was provided by upregulation of antioxidants particularly by total phenolics, ascorbate and ascorbate peroxidase in rice seedlings. Data presented in this study conclusively proved that rice cultivar Kanchana respond to different environmental signals independently and tolerance mechanisms to individual stress factors was also varied. Copyright © 2017 Elsevier B.V. All rights reserved.

Ultraviolet B irradiation of the mouse eye induces pigmentation of the skin more strongly than does stress loading, by increasing the levels of prohormone convertase 2 and α-melanocyte-stimulating hormone.

PubMed

Hiramoto, K; Yamate, Y; Kobayashi, H; Ishii, M; Sato, E F; Inoue, M

2013-01-01

In previous studies, we made the unexpected finding that in mice, ultraviolet (UV)B irradiation of the eye increased the concentration of α-melanocyte-stimulating hormone (α-MSH) in plasma, and systemically stimulated epidermal melanocytes. To compare the extent of the pigmentation induced by social and restraint stress (which activate the hippocampus-pituitary system) with that induced by UVB irradiation. DBA/2 and sham-operated or hypophysectomized DBA/2 mice were subjected to local UVB exposure using a sunlamp directed at the eye, and two types of stress (social and restraint) were imposed. UVB irradiation of the eye or exposure to stress loading both increased the number of Dopa-positive melanocytes in the epidermis, and hypophysectomy strongly inhibited the UVB-induced and stress-induced stimulation of melanocytes. Irradiation of the eye caused a much greater increase in dopamine than did the stress load. Both UVB eye irradiation and stress increased the blood levels of α-MSH and adrenocorticotropic hormone (ACTH). In addition, the increase in plasma α-MSH was greater in animals subjected to UVB eye irradiation than in those subjected to stress loading, whereas the reverse occurred for plasma ACTH. UVB irradiation to the eye and stress loading increased the expression of prohormone convertase (PC)1/3 and PC2 in the pituitary gland. The increase in expression of pituitary PC2 was greater in animals subjected to UVB eye irradiation than to stress, whereas no difference was seen between the two groups for the increase in PC1/3. UVB eye irradiation exerts a stronger effect on pigmentation than stress loading, and is related to increased levels of α-MSH and PC2. © The Author(s). CED © 2012 British Association of Dermatologists.

Topical application of glycolic acid suppresses the UVB induced IL-6, IL-8, MCP-1 and COX-2 inflammation by modulating NF-κB signaling pathway in keratinocytes and mice skin.

PubMed

Tang, Sheau-Chung; Liao, Pei-Yun; Hung, Sung-Jen; Ge, Jheng-Siang; Chen, Shiou-Mei; Lai, Ji-Ching; Hsiao, Yu-Ping; Yang, Jen-Hung

2017-06-01

Glycolic acid (GA), commonly present in fruits, has been used to treat dermatological diseases. Extensive exposure to solar ultraviolet B (UVB) irradiation plays a crucial role in the induction of skin inflammation. The development of photo prevention from natural materials represents an effective strategy for skin keratinocytes. The aim of this study was to investigate the molecular mechanisms underlying the glycolic acid (GA)-induced reduction of UVB-mediated inflammatory responses. We determined the effects of different concentrations of GA on the inflammatory response of human keratinocytes HaCaT cells and C57BL/6J mice dorsal skin. After GA was topically applied, HaCaT and mice skin were exposed to UVB irradiation. GA reduced the production of UVB-induced nuclear factor kappa B (NF-κB)-dependent inflammatory mediators [interleukin (IL)-1β, IL-6, IL-8, cyclooxygenase (COX)-2, tumor necrosis factor-α, and monocyte chemoattractant protein (MCP-1)] at both mRNA and protein levels. GA inhibited the UVB-induced promoter activity of NF-κB in HaCaT cells. GA attenuated the elevation of senescence associated with β-galactosidase activity but did not affect the wound migration ability. The topical application of GA inhibited the genes expression of IL-1β, IL-6, IL-8, COX-2, and MCP-1 in UVB-exposed mouse skin. The mice to UVB irradiation after GA was topically applied for 9 consecutive days and reported that 1-1.5% of GA exerted anti-inflammatory effects on mouse skin. We clarified the molecular mechanism of GA protection against UVB-induced inflammation by modulating NF-κB signaling pathways and determined the optimal concentration of GA in mice skin exposed to UVB irradiation. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

Protective effect of fermented Cyclopia intermedia against UVB-induced damage in HaCaT human keratinocytes.

PubMed

Im, A-Rang; Yeon, Sung Hum; Lee, Jung Seung; Um, Key An; Ahn, Young-Joon; Chae, Sungwook

2016-07-29

The fermented leaves and stems of Cyclopia intermedia are used to brew honeybush tea, a herbal tea indigenous to South Africa. The aim of this study was to evaluate the protective effect of fermented honeybush extracts (FH ex) and scale-up fermented honeybush extracts (SFH ex) against ultraviolet B (UVB)-induced damage in HaCaT keratinocytes. To this end, we examined UVB-induced cell viability, antioxidant enzymes, and inflammatory mediators in HaCaT cells. UVB significantly decreased HaCaT cell viability, whereas FH ex and SFH ex did not exhibit cytotoxic effects and increased the viability of the HaCaT cells. To further investigate the protective effects of FH ex on UVB-induced oxidative stress in HaCaT cells, the activities of superoxide dismutase (SOD), catalase (CAT), matrix metalloproteinases (MMPs), pro-inflammatory cytokines and skin barrier function in terms of involucrin, filaggrin, and loricrin were analyzed. UVB-induced treatment reduced the activity of antioxidant enzymes and skin barrier function, while FH ex or SFH ex increased their activity. These results suggest that FH ex exerted cytoprotective activity against UVB-induced oxidative stress in HaCaT cells through stimulation of antioxidant enzymes activities. Furthermore, FH ex and SFH ex suppressed the UVB-induced expression of inflammatory mediators, such as IL-1β, IL-6, and IL-8, at mRNA level together with down regulation of matrix metalloproteinase (MMPs). In addition, FH ex and SFH ex reversed the phosphorylation of mitogen-activated protein kinase (MAPK) induced by UVB-irradiation. Notably, FH ex and SFH ex markedly inhibited UVB-induced activation of ERK, p38, and JNK. Thus, this agent exhibits anti-oxidative and -inflammatory effects via lowering ROS production, suppressing p38, ERK, and JNK activation, and down-regulating expression of MMPs. These findings suggest that FH ex and SFH ex can be used as a skin anti-photoaging agent.

Preventive effects of β-thujaplicin against UVB-induced MMP-1 and MMP-3 mRNA expressions in skin fibroblasts.

PubMed

Cherng, Jong Yuh; Chen, Li Yin; Shih, Mei Fen

2012-01-01

Solar UV radiation damages human skin by affecting skin tone and resiliency and leads to premature aging (photoaging). The skin damage is caused by the activation of the AP-1 transcription factor, which increases matrix metalloproteinase (MMP) expression and collagen degradation. An increase of interleukin (IL)-6 is also correlated with the activation of MMP-1 expression. β-thujaplicin has shown both acaricidal and antimicrobial activities. Also, β-thujaplicin has been shown to be protective against apoptosis due to the oxidative effects of UV irradiation. However, the effect of β-thujaplicin on UVB-induced MMPs had not been investigated. In this study, after UVB exposure, MMP-1 and IL-6 production in human skin fibroblasts was examined in the presence of β-thujaplicin, vitamin C, and vitamin E. The expression of MMP-1, MMP-3, tissue inhibitor of metalloproteinase (TIMP-1, TIMP-3) and procollagen mRNA was also investigated. Results showed that UVB-induced MMP-1 production was suppressed by the β-thujaplicin treatment in a dose-dependent manner, but not by vitamin C and vitamin E. β-thujaplicin also prevented the up-regulation of MMP-1 and MMP-3 mRNA. Moreover, the UVB-suppressed procollagen gene expression was restored to normal by β-thujaplicin. Neither UVB nor β-thujaplicin affected the mRNA expression of TIMP-1 and TIMP-3. The IL-6 production induced by UVB was lower in β-thujaplicin treated fibroblasts than in the controls. In conclusion, this study shows the capability of β-thujaplicin in preventing MMP-1 production due to UVB irradiation via inhibition of MMP gene expression. Importantly, the UVB-suppressed procollagen gene expression can be restored to normal by β-thujaplicin. These findings indicate that β-thujaplicin is a promising and potent agent to inhibit UVB-induced MMP-1 and MMP-3 gene expression in skin fibroblasts.

Atmospheric constituents and surface-level UVB: Implications for a paleoaltimetry proxy and attempts to reconstruct UV exposure during volcanic episodes

NASA Astrophysics Data System (ADS)

Thomas, Brian C.; Goracke, Byron D.; Dalton, Sean M.

2016-11-01

Chemical and morphological features of spores and pollens have been linked to changes in solar ultraviolet radiation (specifically UVB, 280-315 nm) at Earth's surface. Variation in UVB exposure as inferred from these features has been suggested as a proxy for paleoaltitude; such proxies are important in understanding the uplift history of high altitude plateaus, which in turn is important for testing models of the tectonic processes responsible for such uplift. While UVB irradiance does increase with altitude above sea level, a number of other factors affect the irradiance at any given place and time. In this modeling study we use the TUV atmospheric radiative transfer model to investigate dependence of surface-level UVB irradiance and relative biological impact on a number of constituents in Earth's atmosphere that are variable over long and short time periods. We consider changes in O3 column density, and SO2 and sulfate aerosols due to periods of volcanic activity, including that associated with the formation of the Siberian Traps. We find that UVB irradiance may be highly variable under volcanic conditions and variations in several of these atmospheric constituents can easily mimic or overwhelm changes in UVB irradiance due to changes in altitude. On the other hand, we find that relative change with altitude is not very sensitive to different sets of atmospheric conditions. Any paleoaltitude proxy based on UVB exposure requires confidence that the samples under comparison were located at roughly the same latitude, under very similar O3 and SO2 columns, with similar atmospheric aerosol conditions. In general, accurate estimates of the surface-level UVB exposure at any time and location require detailed radiative transfer modeling taking into account a number of atmospheric factors; this result is important for paleoaltitude proxies as well as attempts to reconstruct the UV environment through geologic time and to tie extinctions, such as the end-Permian mass extinction, to UVB irradiance changes.

Preparation and thermoluminescent dosimetry features of high sensitivity LiF:Mg,Ce phosphor

NASA Astrophysics Data System (ADS)

Shoushtari, M. K.; Zahedifar, M.; Sadeghi, E.

2018-04-01

Thermoluminescence (TL) kinetics and dosimetry features of newly produced LiF doped with Mg and Ce were investigated. Different contents of Mg (0-1 mol%) and Ce (0-2 mol%) were introduced in host material by melting method. The most TL sensitivity of the fabricated phosphor was obtained at 0.7 and 0.05 mol% concentrations of Mg and Ce impurities, respectively. The optimum pre-irradiation annealing regime of the synthesized LiF-based material was found at 350 °C for 10 min. Kinetic parameters of LiF:Mg,Ce dosimeter were obtained using different methods of computerized glow curve deconvolution (CGCD), initial rise (IR) and isothermal decay (ID). A good conformity are observed between the results obtained from different kinetic analysis methods. Other TL features such as fading, dose response and reusability were also examined.

Thermoluminescence (TL) dosimeter of dysprosium doped strontium borate glass for different glass modifiers (Na, Li, Ca) subjected from 1 to 9 Gy doses

NASA Astrophysics Data System (ADS)

Hamzah, S. A.; Saeed, M. A.; Wagiran, H.; Hashim, I. H.

2017-10-01

This article reports TL response for different glass modifier and doping concentration. Alkali oxides (Na2O and Li2O) and alkali earth oxide (CaO) will be used as a glass modifier for strontium borate based glass. The samples were prepared by melt quenching technique. Dy2O3 concentrations ranging from 0.00 to 0.70 mol% and exposure doses of 1 to 9 Gy will be varied. All glass samples exhibit the prominent peak temperature positioned at 186 oC to 232 oC. From all the samples, one of the samples shows an excellent linearity dose response, higher TL and show good reproducibility after 5 cycles exposure which is sodium strontium borate doped with 0.1 mol% Dy2O3 (optimum concentration).

LED phototherapy in full-thickness burns induced by CO2 laser in rats skin.

PubMed

da Silva Melo, Milene; Alves, Leandro Procópio; Fernandes, Adriana Barrinha; Carvalho, Henrique Cunha; de Lima, Carlos José; Munin, Egberto; Gomes, Mônica Fernandes; Salgado, Miguel Angel Castillo; Zângaro, Renato Amaro

2018-04-27

Many studies have been conducted on the treatment of burns because they are important in morbidity and mortality. These studies are mainly focused on improving care and quality of life of patients. The aim of this study was evaluate the LED phototherapy effects in rats skin full-thickness burns induced by CO 2 laser. The animals were divided in NT group that did not received any treatment and LED group that received LED irradiation at 685 nm, 220 mW, and 4.5 J/cm 2 during 40 s by burned area. Biopsies were obtained after 7, 14, and 21 days of treatment and submitted to histological and immunohistochemical analysis. The LED phototherapy shows anti-inflammatory effects, improves angiogenesis, and stimulates the migration and proliferation of fibroblasts. The T CD8+ lymphocytes were more common in burned areas compared to T CD4+ lymphocytes since statistically significant differences were observed in the LED group compared to the NT group after 7 days of treatment. These results showed that LED phototherapy performs positive influence in full-thickness burns repair from the healing process modulated by cellular immune response. The obtained results allowed inferring that burns exhibit a characteristic cell immune response and this cannot be extrapolated to other wounds such as incision and wounds induced by punch, among others.

Role of oral zinc supplementation for reduction of neonatal hyperbilirubinemia: a systematic review of current evidence.

PubMed

Sharma, Deepak; Farahbakhsh, Nazanin; Sharma, Pradeep; Shastri, Sweta

2017-08-01

Neonatal hyperbilirubinemia is frequently seen condition in the NICU. Oral zinc has been tried for the prevention of hyperbilirubinemia. To evaluate the role of oral zinc supplementation for reduction of neonatal hyperbilirubinemia in term and preterm infants. The literature search was done for various randomized control trial (RCT) by searching the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, Web of Science, Scopus, Index Copernicus, African Index Medicus (AIM), Thomson Reuters (ESCI), Chemical Abstracts Service (CAS) and other data base. This review included six RCT that fulfilled inclusion criteria. One study evaluated the role of zinc in very low birth weight (VLBW) infants and remaining enrolled neonates  ≥35 weeks of gestation. The dose of zinc varied from 5 to 20 mg/day and duration from 5-7 days. All the studies used zinc sulfate, only one study used zinc gluconate. The total neonates enrolled in these different RCT are 749. Role of zinc in the prevention of neonatal hyperbilirubinemia is not supported by the current evidence. Only one study was able to show reduction in the mean TSB level and requirement of phototherapy with zinc, and the remaining studies did not report any positive effect. None of the studies showed any effect on the duration of phototherapy, incidence of phototherapy, age of starting of phototherapy and any serious adverse effect.

Interaction of moderate UV-B exposure and temperature on the formation of structurally different flavonol glycosides and hydroxycinnamic acid derivatives in kale (Brassica oleracea var. sabellica).

PubMed

Neugart, Susanne; Fiol, Michaela; Schreiner, Monika; Rohn, Sascha; Zrenner, Rita; Kroh, Lothar W; Krumbein, Angelika

2014-05-07

Kale has a high number of structurally different flavonol glycosides and hydroxycinnamic acid derivatives. In this study we investigated the interaction of moderate UV-B radiation and temperature on these compounds. Kale plants were grown at daily mean temperatures of 5 or 15 °C and were exposed to five subsequent daily doses (each 0.25 kJ m(-2) d(-1)) of moderate UV-B radiation at 1 d intervals. Of 20 phenolic compounds, 11 were influenced by an interaction of UV-B radiation and temperature, e.g., monoacylated quercetin glycosides. Concomitantly, enhanced mRNA expression of flavonol 3'- hydroxylase showed an interaction of UV-B and temperature, highest at 0.75 kJ m(-2) and 15 °C. Kaempferol glycosides responded diversely and dependent on, e.g., the hydroxycinnamic acid residue. Compounds containing a catechol structure seem to be favored in the response to UV-B. Taken together, subsequent exposure to moderate UV-B radiation is a successful tool for enhancing the flavonoid profile of plants, and temperature should be considered.

Tualang honey protects keratinocytes from ultraviolet radiation-induced inflammation and DNA damage.

PubMed

Ahmad, Israr; Jimenez, Hugo; Yaacob, Nik Soriani; Yusuf, Nabiha

2012-01-01

Malaysian tualang honey possesses strong antioxidant and anti-inflammatory properties. Here, we evaluated the effect of tualang honey on early biomarkers of photocarcinogenesis employing PAM212 mouse keratinocyte cell line. Keratinocytes were treated with tualang honey (1.0%, v/v) before a single UVB (150 mJ cm(-2) ) irradiation. We found that the treatment of tualang honey inhibited UVB-induced DNA damage, and enhanced repair of UVB-mediated formation of cyclobutane pyrimidine dimers and 8-oxo-7,8-dihydro-2'-deoxyguanosine. Treatment of tualang honey inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in murine keratinocyte cell line. The treatment of tualang honey also inhibited UVB-induced inflammatory cytokines and inducible nitric oxide synthase protein expression. Furthermore, the treatment of tualang honey inhibited UVB-induced COX-2 expression and PGE2 production. Taken together, we provide evidence that the treatment of tualang honey to keratinocytes affords substantial protection from the adverse effects of UVB radiation via modulation in early biomarkers of photocarcinogenesis and provide suggestion for its photochemopreventive potential. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

VcBBX, VcMYB21, and VcR2R3MYB Transcription Factors Are Involved in UV-B-Induced Anthocyanin Biosynthesis in the Peel of Harvested Blueberry Fruit.

PubMed

Nguyen, Chau T T; Lim, Sooyeon; Lee, Jeong Gu; Lee, Eun Jin

2017-03-15

This study was carried out to better understand the mechanism responsible for increasing the anthocyanins in blueberries after UV-B radiation at 6.0 kJ m -2 for 20 min. UV-B induced upregulation of genes involved in anthocyanin biosynthesis in blueberry fruit compared to a nontreated control. Phenylalanine ammonia lyase, chalcone synthase, and flavanone 3'-hydroxylase, which are enzymes that function upstream of anthocyanin biosynthesis, were significantly expressed by UV-B. Expression levels of VcBBX, VcMYB21, and VcR2R3MYB transcription factors (TFs) were upregulated by UV-B in the same manner as the anthocyanin biosynthesis genes. The significant increase in the expression of TFs occurred immediately after UV-B treatment and was then maximized within 3 h. In accordance with these changes, individual anthocyanin contents in the fruits treated with UV-B significantly increased within 6 h and were 2-3-fold higher than the control. Our results indicated that UV-B radiation stimulates an increase in anthocyanin biosynthesis, which could be upregulated by the TFs studied.

Caffeic Acid Inhibits Chronic UVB-Induced Cellular Proliferation Through JAK-STAT3 Signaling in Mouse Skin.

PubMed

Agilan, Balupillai; Rajendra Prasad, N; Kanimozhi, Govindasamy; Karthikeyan, Ramasamy; Ganesan, Muthusamy; Mohana, Shanmugam; Velmurugan, Devadasan; Ananthakrishnan, Dhanapalan

2016-05-01

Signal transducers and activators of transcription 3 (STAT3) play a critical role in inflammation, proliferation and carcinogenesis. Inhibition of JAK-STAT3 signaling is proved to be a novel target for prevention of UVB-induced skin carcinogenesis. In this study, chronic UVB irradiation (180 mJ cm(-2) ; weekly thrice for 30 weeks) induces the expression of IL-10 and JAK1 that eventually activates the STAT3 which leads to the transcription of proliferative and antiapoptotic markers such as PCNA, Cyclin-D1, Bcl2 and Bcl-xl, respectively. Caffeic acid (CA) inhibits JAK-STAT3 signaling, thereby induces apoptotic cell death by upregulating Bax, Cytochrome-C, Caspase-9 and Caspase-3 expression in mouse skin. Furthermore, TSP-1 is an antiangiogeneic protein, which is involved in the inhibition of angiogenesis and proliferation. Chronic UVB exposure decreased the expression of TSP-1 and pretreatment with CA prevented the UVB-induced loss of TSP-1 in UVB-irradiated mouse skin. Thus, CA offers protection against UVB-induced photocarcinogenesis probably through modulating the JAK-STAT3 in the mouse skin. © 2016 The American Society of Photobiology.

Cell damage caused by ultraviolet B radiation in the desert cyanobacterium Phormidium tenue and its recovery process.

PubMed

Wang, Gaohong; Deng, Songqiang; Liu, Jiafeng; Ye, Chaoran; Zhou, Xiangjun; Chen, Lanzhou

2017-10-01

Phormidium tenue, a cyanobacterium that grows in the topsoil of biological soil crusts (BSCs), has the highest recovery rate among desert crust cyanobacteria after exposure to ultraviolet B (UV-B) radiation. However, the mechanism underlying its recovery process is unclear. To address this issue, we measured chlorophyll a fluorescence, generation of reactive oxygen species (ROS), lipid peroxidation, and repair of DNA breakage in P. tenue following exposure to UV-B. We found that UV-B radiation at all doses tested reduced photosynthesis and induced cell damage in P. tenue. However, P. tenue responded to UV-B radiation by rapidly reducing photosynthetic activity, which protects the cell by leaking less ROS. Antioxidant enzymes, DNA damage repair systems, and UV absorbing pigments were then induced to mitigate the damage caused by UV-B radiation. The addition of exogenous antioxidant chemicals ascorbate and N-acetylcysteine also mitigated the harmful effects caused by UV-B radiation and enhanced the recovery process. These chemicals could aid in the resistance of P. tenue to the exposure of intense UV-B radiation in desertified areas when inoculated onto the sand surface to form artificial algal crusts. Copyright © 2017. Published by Elsevier Inc.

The measurement and analysis of normal incidence solar UVB radiation and its application to the photoclimatherapy protocol for psoriasis at the Dead Sea, Israel.

PubMed

Kudish, Avraham I; Harari, Marco; Evseev, Efim G

2011-01-01

The broad-band normal incidence UVB beam radiation has been measured at Neve Zohar, Dead Sea basin, using a prototype tracking instrument composed of a Model 501A UV-Biometer mounted on an Eppley Solar Tracker Model St-1. The diffuse and beam fraction of the solar global UVB radiation have been determined using the concurrently measured solar global UVB radiation. The diffuse fraction was observed to exceed 80% throughout the year. The application of the results of these measurements to the possible revision of the photoclimatherapy protocol for psoriasis patients at the Dead Sea medical spas is now under investigation. The suggested revision would enable the sun-exposure treatment protocol to take advantage of the very high diffuse fraction by allowing the patient to receive the daily dose of UVB radiation without direct exposure to the sun, viz. receive the diffuse UVB radiation under a sunshade. This would require an increase in sun-exposure time intervals, as the UVB radiation intensity beneath a sunshade is less than that on an exposed surface. © 2010 The Authors. Photochemistry and Photobiology © 2010 The American Society of Photobiology.

Protective effect of rare earth against oxidative stress under ultraviolet-B radiation.

PubMed

Wang, Lihong; Huang, Xiaohua; Zhou, Qing

2009-04-01

The effects of lanthanum (III) (La(III)) in protecting soybean leaves against oxidative stress induced by ultraviolet-B (UV-B) radiation were investigated. The increase in contents of hydrogen peroxide (H(2)O(2)) and superoxide (O2*-) due to UV-B radiation suggested oxidative stress. The increase in the content of malondialdehyde (MDA) and the decrease in the index of unsaturated fatty acid (IUFA) indicated oxidative damage on cell membrane induced by UV-B radiation. La(III) partially reversed UV-B-radiation-induced damage of plant growth. The reduction in the contents of H(2)O(2), O2*-, and MDA and increase in the content of IUFA, compared with UV-B treatment, also indicated that La(III) alleviated the oxidative damage induced by UV-B radiation. The increase in the activities of superoxide dismutase and peroxidase and the contents of ascorbate, carotenoids, and flavonoids were observed in soybean leaves with La(III) + UV-B treatment, compared with UV-B treatment. Our data suggested that La(III) could protect soybean plants from UV-B-radiation-induced oxidative stress by reacting with reactive oxygen species directly or by improving the defense system of plants.

Lycium barbarum polysaccharide protects human keratinocytes against UVB-induced photo-damage.

PubMed

Li, Huaping; Li, Zhenjie; Peng, Liqian; Jiang, Na; Liu, Qing; Zhang, Erting; Liang, Bihua; Li, Runxiang; Zhu, Huilan

2017-02-01

Ultraviolet B (UVB) irradiation plays a key role in skin damage, which induces oxidative and inflammatory damages, thereby causing photoaging or photocarcinogenesis. Lycium barbarum polysaccharide (LBP), the most biologically active fraction of wolfberry, possesses significant antioxidative and anti-inflammatory effects on multiple tissues. In the present study, the photoprotective effects and potential underlying molecular mechanisms of LBP against UVB-induced photo-damage were investigated in immortalized human keratinocytes (HaCaT cells). The data indicated that pretreatment with LBP significantly attenuated UVB-induced decrease in cell viability, increase in ROS production and DNA damage. LBP also significantly suppressed UVB-induced p38 MAPK activation, and subsequently reversed caspase-3 activation and MMP-9 expression. Notably, LBP was found to induce Nrf2 nuclear translocation and increase the expression of Nrf2-dependent ARE target genes. Furthermore, the protective effects of LBP were abolished by siRNA-mediated Nrf2 silencing. These results showed that the antioxidant LBP could partially protect against UVB irradiation-induced photo-damage through activation of Nrf2/ARE pathway, thereby scavenging ROS and reducing DNA damage, and subsequently suppressing UVB-induced p38 MAP pathway. Thus, LBP can be potentially used for skincare against oxidative damage from environmental insults.

Polypeptide from Chlamys farreri inhibits UVB-induced apoptosis of HaCaT cells via iNOS/NO and HSP90

NASA Astrophysics Data System (ADS)

Zhang, Zhengyang; Liu, Xiaojin; Liu, Tuo; Yan, Lin; Wang, Yuejun; Wang, Chunbo

2009-09-01

Polypeptide from Chlamys farreri (PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri, and was found to be an effective antioxidant in our recent studies. In this study, we investigated the effect of PCF on ultraviolet B (UVB)-induced apoptosis of HaCaT cells and the intracellular signaling pathways involved. Pretreatment with the inducible nitric oxide synthase (iNOS) inhibitor S-methylisothiourea sulfate inhibited UVB-induced apoptosis, indicating that iNOS and NO play important roles in apoptosis. On the other hand, the inhibition of UVB-induced apoptosis in the immortalized keratinocyte (HaCaT) cells by PCF was estimated using a DNA ladder. PCF treatment inhibited UVB-induced iNOS activation, as determined by RT-PCR, NO production, as determined by ESR, and up-regulated heat shock protein (HSP) 90 activation, as determined by Western blotting. Our results indicate that iNOS and NO are involved in UVB-induced apoptosis of HaCaT cells and the protective effect of PCF against UVB irradiation is exerted by suppressing the expression of iNOS, followed by inhibition of NO release and enhanced activation of HSP90.

UVB-induced mutagenesis in hairless {lambda}lacZ-transgenic mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frijhoff, A.F.W.; Rebel, H.; Mientjes, E.J.

UVB-induced mutagenesis was studied in hairless 40.6 transgenic mice (Muta{trademark}Mouse), which contain the {lambda}gt1OlacZ shuttle vector as a target for mutagenesis. Mice were exposed at the dorsal side to either single doses of 200, 500, 800, or 1000 J/m{sup 2} UVB or to two successive irradiations of either 200 and 800 J/m{sup 2} UVB, with intervals of 1,3, or 5 days, or to 800 and 200 J/m{sup 2} UVB with a 5-day interval. At 23 days after the last exposure, lacZ mutant frequencies (MF) were determined in the epidermis. The lacZ MF increased linearly with increasing dose of UVB. Themore » mutagenic effect of two successive irradiations appeared to be additive. The UV-induced mutation spectrum was dominated by G:C{r_arrow}A:T transitions at dipyrimidine sites. DNA-sequence analysis of spontaneously mutated phages showed a diverse spectrum consisting of insertions, deletions and G:C {r_arrow} A:T transitions at CpG sites. the results indicate that the hairless {lambda}lacZ-transgenic mouse is a suitable in vivo model for studying UVB-induced mutations. 29 refs., 5 tabs.« less

Salubrinal protects human skin fibroblasts against UVB-induced cell death by blocking endoplasmic reticulum (ER) stress and regulating calcium homeostasis.

PubMed

Ji, Chao; Yang, Bo; Huang, Shu-Ying; Huang, Jin-Wen; Cheng, Bo

2017-12-02

The role of UVB in skin photo damages has been widely reported. Overexposure to UVB will induce severe DNA damages in epidermal cells and cause most cytotoxic symptoms. In the present study, we tested the potential activity of salubrinal, a selective inhibitor of Eukaryotic Initiation Factor 2 (eIF2) -alpha phosphatase, against UV-induced skin cell damages. We first exposed human fibroblasts to UVB radiation and evaluated the cytosolic Ca 2+ level as well as the induction of ER stress. We found that UVB radiation induced the depletion of ER Ca 2+ and increased the expression of ER stress marker including phosphorylated PERK, CHOP, and phosphorylated IRE1α. We then determined the effects of salubrinal in skin cell death induced by UVB radiation. We observed that cells pre-treated with salubrinal had a higher survival rate compared to cells treated with UVB alone. Pre-treatment with salubrinal successfully re-established the ER function and Ca 2+ homeostasis. Our results suggest that salubrinal can be a potential therapeutic agents used in preventing photoaging and photo damages. Copyright © 2017 Elsevier Inc. All rights reserved.

Micro-Raman spectroscopy study of the effect of Mid-Ultraviolet radiation on erythrocyte membrane.

PubMed

Li, N; Li, S X; Guo, Z Y; Zhuang, Z F; Li, R; Xiong, K; Chen, S J; Liu, S H

2012-07-02

Mid-Ultraviolet (UVB) has a significant influence on human health. In this study, human erythrocytes were exposed to UVB to investigate the effects of UVB radiation on erythrocytes membrane. And Micro-Raman spectroscopy was employed to detect the damage. Principal component analysis (PCA) was used to classify the control erythrocytes and the irradiated erythrocytes. Results showed that the erythrocytes membrane was damaged by Mid-Ultraviolet (UVB) radiation. The intensity of the Raman peaks at 1126 cm(-1) and 1082 cm(-1) were used to calculate the Longitudinal Order-Parameters in Chains (S(trans)) which can present the liquidity and ionic permeability of erythrocyte membrane. After UVB radiation for 30 min, both the liquidity and ionic permeability decreased. At the same time, the intensity of the peaks at 1302 cm(-1) (α-helix), 1254 cm(-1) (random coil), 1452 cm(-1) and 1430 cm(-1) (CH(2)/CH(3) stretch) have also changed which indicated the membrane protein also been damaged by UVB. In the whole process of radiation, the more UVB radiation dose the more damage on the erythrocyte membrane. Copyright © 2012 Elsevier B.V. All rights reserved.

Ultraviolet A within Sunlight Induces Mutations in the Epidermal Basal Layer of Engineered Human Skin

PubMed Central

Huang, Xiao Xuan; Bernerd, Françoise; Halliday, Gary Mark

2009-01-01

The ultraviolet B (UVB) waveband within sunlight is an important carcinogen; however, UVA is also likely to be involved. By ascribing mutations to being either UVB or UVA induced, we have previously shown that human skin cancers contain similar numbers of UVB- and UVA-induced mutations, and, importantly, the UVA mutations were at the base of the epidermis of the tumors. To determine whether these mutations occurred in response to UV, we exposed engineered human skin (EHS) to UVA, UVB, or a mixture that resembled sunlight, and then detected mutations by both denaturing high-performance liquid chromatography and DNA sequencing. EHS resembles human skin, modeling differential waveband penetration to the basal, dividing keratinocytes. We administered only four low doses of UV exposure. Both UVA and UVB induced p53 mutations in irradiated EHS, suggesting that sunlight doses that are achievable during normal daily activities are mutagenic. UVA- but not UVB-induced mutations predominated in the basal epidermis that contains dividing keratinocytes and are thought to give rise to skin tumors. These studies indicate that both UVA and UVB at physiological doses are mutagenic to keratinocytes in EHS. PMID:19264911

SU-D-206-06: Task-Specific Optimization of Scintillator Thickness for CMOS-Detector Based Cone-Beam Breast CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vedantham, S; Shrestha, S; Shi, L

Purpose: To optimize the cesium iodide (CsI:Tl) scintillator thickness in a complimentary metal-oxide semiconductor (CMOS)-based detector for use in dedicated cone-beam breast CT. Methods: The imaging task considered was the detection of a microcalcification cluster comprising six 220µm diameter calcium carbonate spheres, arranged in the form of a regular pentagon with 2 mm spacing on its sides and a central calcification, similar to that in ACR-recommended mammography accreditation phantom, at a mean glandular dose of 4.5 mGy. Generalized parallel-cascades based linear systems analysis was used to determine Fourier-domain image quality metrics in reconstructed object space, from which the detectability indexmore » inclusive of anatomical noise was determined for a non-prewhitening numerical observer. For 300 projections over 2π, magnification-associated focal-spot blur, Monte Carlo derived x-ray scatter, K-fluorescent emission and reabsorption within CsI:Tl, CsI:Tl quantum efficiency and optical blur, fiberoptic plate transmission efficiency and blur, CMOS quantum efficiency, pixel aperture function and additive noise, and filtered back-projection to isotropic 105µm voxel pitch with bilinear interpolation were modeled. Imaging geometry of a clinical prototype breast CT system, a 60 kV Cu/Al filtered x-ray spectrum from 0.3 mm focal spot incident on a 14 cm diameter semi-ellipsoidal breast were used to determine the detectability index for 300–600 µm thick (75µm increments) CsI:Tl. The CsI:Tl thickness that maximized the detectability index was considered optimal. Results: The limiting resolution (10% modulation transfer function, MTF) progressively decreased with increasing CsI:Tl thickness. The zero-frequency detective quantum efficiency, DQE(0), in projection space increased with increasing CsI:Tl thickness. The maximum detectability index was achieved with 525µm thick CsI:Tl scintillator. Reduced MTF at mid-to-high frequencies for 600µm thick CsI:Tl lowered the detectability index than 525µm CsI:Tl. Conclusion: For the x-ray spectrum and imaging conditions considered, a 525µm thick CsI:Tl scintillator integrated with the CMOS detector is optimal for detecting microcalcification cluster. Funding support: Supported in part by NIH R01 CA195512. The contents are solely the responsibility of the authors and do not reflect the official views of the NIH or the NCI. Disclosures: SV, GV and AK - Research collaboration, Koning Corp., West Henrietta, NY.« less

Influence of UVB exposure on the vitamin D status and calcium homoeostasis of growing sheep and goats.

PubMed

Kovács, S; Wilkens, M R; Liesegang, A

2015-04-01

The purpose of this study was to investigate the influence of exposure to ultraviolet radiation (UVB) on vitamin D status, intestinal calcium absorption and bone metabolism in growing sheep and goats. The hypothesis was that growing sheep and goats are able to synthesise vitamin D within their skin as a result of UVB exposure and that respective consequences for their vitamin D blood levels and the associated parameters can be shown. Fourteen 18-week-old lambs and goat kids were kept in an UVB-free environment and randomly assigned to two groups. One group was daily exposed to UVB (300 watt) for 12 weeks, and the other served as a control group. Except for the exposure to UVB, all animals were kept under the same conditions and fed according to their requirements. Before the start of the experiment and every second week, blood samples were taken. Also the left metatarsus of each animal was analysed by quantitative computer tomography to test for bone mineral status before the start, in week 7 and at the end of the experiment. After 12 weeks, the animals were slaughtered and samples were taken from skin, gastrointestinal tract and kidney for further analyses. In this study, exposure to UVB led to increased serum 1,25-dihydroxyvitamin D (1,25VitD) levels in goat kids, whereas in lambs, serum 25-hydroxyvitamin D (25VitD) levels were increased. In both species UVB-exposed animals showed lower 7-dehydrocholesterol (7DHC) values in skin than their respective control groups. These results indicate that growing goat kids and lambs are able to synthesise vitamin D in the skin when being exposed to UVB. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Effect of Solar Ultraviolet-B Radiation during Springtime Ozone Depletion on Photosynthesis and Biomass Production of Antarctic Vascular Plants1

PubMed Central

Xiong, Fusheng S.; Day, Thomas A.

2001-01-01

We assessed the influence of springtime solar UV-B radiation that was naturally enhanced during several days due to ozone depletion on biomass production and photosynthesis of vascular plants along the Antarctic Peninsula. Naturally growing plants of Colobanthus quitensis (Kunth) Bartl. and Deschampsia antarctica Desv. were potted and grown under filters that absorbed or transmitted most solar UV-B. Plants exposed to solar UV-B from mid-October to early January produced 11% to 22% less total, as well as above ground biomass, and 24% to 31% less total leaf area. These growth reductions did not appear to be associated with reductions in photosynthesis per se: Although rates of photosynthetic O2 evolution were reduced on a chlorophyll and a dry-mass basis, on a leaf area basis they were not affected by UV-B exposure. Leaves on plants exposed to UV-B were denser, probably thicker, and had higher concentrations of photosynthetic and UV-B absorbing pigments. We suspect that the development of thicker leaves containing more photosynthetic and screening pigments allowed these plants to maintain their photosynthetic rates per unit leaf area. Exposure to UV-B led to reductions in quantum yield of photosystem II, based on fluorescence measurements of adaxial leaf surfaces, and we suspect that UV-B impaired photosynthesis in the upper mesophyll of leaves. Because the ratio of variable to maximal fluorescence, as well as the initial slope of the photosynthetic light response, were unaffected by UV-B exposure, we suggest that impairments in photosynthesis in the upper mesophyll were associated with light-independent enzymatic, rather than photosystem II, limitations. PMID:11161031

Impacts of diurnal variation of ultraviolet-B and photosynthetically active radiation on phycobiliproteins of the hot-spring cyanobacterium Nostoc sp. strain HKAR-2.

PubMed

Kannaujiya, Vinod K; Sinha, Rajeshwar P

2017-01-01

The effects of diurnal variation of photosynthetically active radiation (PAR; 400-700 nm) and ultraviolet-B (UV-B; 280-315 nm) radiation on phycobiliproteins (PBPs) and photosynthetic pigments (PP) have been studied in the hot-spring cyanobacterium Nostoc sp. strain HKAR-2. The variations in PBPs and PP were monitored by alternating light and dark under PAR, UV-B, and PAR + UV-B radiations over a period of 25 h. There was a decline in the amount of Chl a and PBPs during light periods of UV-B and PAR + UV-B and an increase during dark periods showing a circadian rhythm by destruction and resynthesis of pigment-protein complex. However, a marked induction in carotenoids was recorded during light periods of the same radiations. Moreover, the ratio of Chl a/PE and Chl a/PC was increased in dark periods showing the resynthesis of bleached Chl a. The wavelength shift in emission fluorescence of PBPs toward shorter wavelengths further indicated the bleaching and destruction of PBPs during light periods. Oxidative damage upon exposure to PAR, UV-B, and PAR + UV-B was alleviated by induction of antioxidative enzymes such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). The studied cyanobacterium exhibits a significant increase in the activities of SOD, CAT, and APX upon exposure to UV-B and PAR + UV-B radiations. The results indicate that pigment-protein composition of Nostoc sp. stain HKAR-2 was significantly altered during diurnal variation of light/radiation, which might play an important role in optimization for their productivity in a particular cyanobacterium.

Oxygen toxicity and antioxidative responses in arsenic stressed Helianthus annuus L. seedlings against UV-B.

PubMed

Yadav, Geeta; Srivastava, Prabhat Kumar; Parihar, Parul; Tiwari, Sanjesh; Prasad, Sheo Mohan

2016-12-01

In order to know the impact of elevated level of UV-B on arsenic stressed Helianthus annuus L. var. DRSF-113 plants, certain physiological (growth - root and shoot lengths, their fresh masses and leaf area; photosynthetic competence and respiration) and biochemical parameters (pigments - Chl a and b, Car, anthocyanin and flavonoids; reactive oxygen species - superoxide radicals, H 2 O 2 ; reactive carbonyl group, electrolyte leakage; antioxidants - superoxide dismutase, peroxidise, catalase, glutathione-S-transferase, proline) of their seedlings were analysed under the simultaneous exposures of two arsenic doses (6mgkg -1 soil, As 1 ; and 12mgkg -1 soil, As 2 ) and two UV-B doses (1.2kJm -2 d -1 , UV-B 1 ; and 3.6kJm -2 d -1 , UV-B 2 ). As 1 and As 2 alone declined all the studied growth parameters - along with photosynthetic pigments which were further aggravated after the simultaneous exposures of predefined levels of UV-B. Each As exposure was accompanied by significant accumulation of As in root, shoot and leaves and was substantiated by simultaneous exposures of UV-B doses which manifested into suppressed growth, decreased chlorophyll contents and photosynthesis. In similar conditions, other photo-shielding pigments, viz. carotenoids, anthocyanin and flavonoids along with respiration and oxidative stress markers such as O 2 • ¯, H 2 O 2 ; and indicators of cell membrane damage like MDA (malondialdehyde), RCG (reactive carbonyl group), electrolyte leakage were enhanced by As, and became more pronounced after the simultaneous exposures of UV-B doses. As doses stimulated the activities of SOD, POD, CAT, GST and Pro which got further accelerated after the simultaneous exposures of UV-B doses. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of UV-B radiation on growth, photosynthesis, UV-B-absorbing compounds and NADP-malic enzyme in bean (Phaseolus vulgaris L.) grown under different nitrogen conditions.

PubMed

Pinto, M E; Casati, P; Hsu, T P; Ku, M S; Edwards, G E

1999-02-01

The effects of UV-B radiation on growth, photosynthesis, UV-B-absorbing compounds and NADP-malic enzyme have been examined in different cultivars of Phaseolous vulgaris L. grown under 1 and 12 mM nitrogen. Low nitrogen nutrition reduces chlorophyll and soluble protein contents in the leaves and thus the photosynthesis rate and dry-matter accumulation. Chlorophyll, soluble protein and Rubisco contents and photosynthesis rate are not significantly altered by ambient levels of UV-B radiation (17 microW m-2, 290-320 nm, 4 h/day for one week). Comparative studies show that under high nitrogen, UV-B radiation slightly enhances leaf expansion and dry-matter accumulation in cultivar Pinto, but inhibits these parameters in Vilmorin. These results suggest that the UV-B effect on growth is mediated through leaf expansion, which is particularly sensitive to UV-B, and that Pinto is more tolerant than Vilmorin. The effect of UV-B radiation on UV-B-absorbing compounds and on NADP-malic enzyme (NADP-ME) activity is also examined. Both UV-B radiation and low-nitrogen nutrition enhance the content of UV-B-absorbing compounds, and among the three cultivars used, Pinto exhibits the highest increases and Arroz the lowest. The same trend is observed for the specific activity and content of NADP-ME. On a leaf-area basis, the amount of UV-B-absorbing compounds is highly correlated with the enzyme activity (r2 = 0.83), suggesting that NADP-ME plays a key role in biosynthesis of these compounds. Furthermore, the higher sensitivity of Vilmorin than Pinto to UV-B radiation appears to be related to the activity of NADP-ME and the capacity of the plants to accumulate UV-B-absorbing compounds.

Silymarin inhibits ultraviolet radiation-induced immune suppression through DNA repair-dependent activation of dendritic cells and stimulation of effector T cells

PubMed Central

Vaid, Mudit; Prasad, Ram; Singh, Tripti; Elmets, Craig A.; Xu, Hui; Katiyar, Santosh K.

2013-01-01

Silymarin inhibits UVB-induced immunosuppression in mouse skin. To identify the molecular mechanisms underlying this effect, we used an adoptive transfer approach in which dendritic cells (DCs) from the draining lymph nodes of donor mice that had been UVB-exposed and sensitized to 2,4,-dinitrofluorobenzene (DNFB) were transferred into naïve recipient mice. The contact hypersensitivity (CHS) response of the recipient mice to DNFB was then measured. When DCs were obtained from UVB-exposed donor mice that were not treated with silymarin, the CHS response was suppressed confirming the role of DCs in the UVB-induced immunosuppression. Silymarin treatment of UVB-exposed donor mice relieved this suppression of the CHS response in the recipients. Silymarin treatment was associated with rapid repair of UVB-induced cyclobutane pyrimidine dimers (CPDs) in DCs and silymarin treatment did not prevent UV-induced immunosuppression in XPA-deficient mice which are unable to repair UV-induced DNA damage. The CHS response in mice receiving DCs from silymarin-treated UV-exposed donor mice also was associated with enhanced secretion of Th1-type cytokines and stimulation of T cells. Adoptive transfer of T cells revealed that transfer of either CD8+ or CD4+ cells from silymarin-treated, UVB-exposed donors resulted in enhancement of the CHS response. Cell culture study showed enhanced secretion of IL-2 and IFNγ by CD8+ T cells, and reduced secretion of Th2 cytokines by CD4+ cells, obtained from silymarin-treated UVB-exposed mice. These data suggest that DNA repair-dependent functional activation of DCs, a reduction in CD4+ regulatory T-cell activity, and stimulation of CD8+ effector T cells contribute to silymarin-mediated inhibition of UVB-induced immunosuppression. PMID:23395695

Estimated ultraviolet radiation doses in wetlands in six national parks

USGS Publications Warehouse

Diamond, S.A.; Trenham, P.C.; Adams, Michael J.; Hossack, B.R.; Knapp, R.A.; Stark, L.; Bradford, D.; Corn, P.S.; Czarnowski, K.; Brooks, P.D.; Fagre, D.B.; Breen, B.; Dentenbeck, N.E.; Tonnessen, K.

2005-01-01

Ultraviolet-B radiation (UV-B, 280–320-nm wavelengths) doses were estimated for 1024 wetlands in six national parks: Acadia (Acadia), Glacier (Glacier), Great Smoky Mountains (Smoky), Olympic (Olympic), Rocky Mountain (Rocky), and Sequoia/Kings Canyon (Sequoia). Estimates were made using ground-based UV-B data (Brewer spectrophotometers), solar radiation models, GIS tools, field characterization of vegetative features, and quantification of DOC concentration and spectral absorbance. UV-B dose estimates were made for the summer solstice, at a depth of 1 cm in each wetland. The mean dose across all wetlands and parks was 19.3 W-h m−2 (range of 3.4–32.1 W-h m−2). The mean dose was lowest in Acadia (13.7 W-h m−2) and highest in Rocky (24.4 W-h m−2). Doses were significantly different among all parks. These wetland doses correspond to UV-B flux of 125.0 μW cm−2 (range 21.4–194.7 μW cm−2) based on a day length, averaged among all parks, of 15.5 h. Dissolved organic carbon (DOC), a key determinant of water-column UV-B flux, ranged from 0.6 (analytical detection limit) to 36.7 mg C L−1 over all wetlands and parks, and reduced potential maximal UV-B doses at 1-cm depth by 1%–87 %. DOC concentration, as well as its effect on dose, was lowest in Sequoia and highest in Acadia (DOC was equivalent in Acadia, Glacier, and Rocky). Landscape reduction of potential maximal UV-B doses ranged from zero to 77% and was lowest in Sequoia. These regional differences in UV-B wetland dose illustrate the importance of considering all aspects of exposure in evaluating the potential impact of UV-B on aquatic organisms.

Z-ligustilide ameliorated ultraviolet B-induced oxidative stress and inflammatory cytokine production in human keratinocytes through upregulation of Nrf2/HO-1 and suppression of NF-κB pathway.

PubMed

Wu, Zhouwei; Uchi, Hiroshi; Morino-Koga, Saori; Shi, Weimin; Furue, Masutaka

2015-09-01

Ultraviolet B (UVB), a harmful environmental factor, is responsible for a variety of skin disorders including skin inflammation through reactive oxygen species (ROS) and inflammatory mediator production. Here, we investigated the effect of Z-ligustilide (Z-lig), an active ingredient isolated from the medicinal plants Cnidium officinale and Angelica acutiloba, on UVB-induced ROS generation and inflammatory mediator production in normal human epidermal keratinocytes (NHEKs) as well as its underlying mechanisms. Z-lig significantly rescued UVB-induced NHEKs damage in a dosage-dependent manner. Pretreatment of NHEKs with Z-lig inhibited UVB-induced ROS production in NHEKs. Both silencing the nuclear factor E2-related factor 2 (Nrf2) and the supplement of tin protoporphyrin IX (SnPP), a haeme oxygenase-1 (HO-1) inhibitor, cancelled the inhibitory effect of Z-lig on UVB-induced ROS upregulation in NHEKs. Moreover, pretreatment of NHEKs with Z-lig reduced UVB-induced nuclear factor kappa B (NF-κB)-dependent inflammatory mediators (IL-6, IL-8 and MCP-1) production at both mRNA and protein level. In the presence of Z-lig, UVB-induced NF-κB subunit p65 nuclear translocation was abolished, and the IκBα degradation was suppressed. Taken together, these findings suggest that Z-lig can suppress UVB-induced ROS generation through Nrf2/HO-1 upregulation and inflammation by suppressing the NF-κB pathway, suggesting that Z-lig may be beneficial in protecting skin from UVB exposure. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Time and dose-response effects of honokiol on UVB-induced skin cancer development.

PubMed

Guillermo, Ruth F; Chilampalli, Chandeshwari; Zhang, Xiaoying; Zeman, David; Fahmy, Hesham; Dwivedi, Chandradhar

2012-06-01

Honokiol has shown chemopreventive effects in chemically-induced and UVB-induced skin cancer in mice. In this investigation, we assessed the time-effects of a topical low dose of honokiol (30 μg), and then the effects of different honokiol doses (30, 45, and 60 μg) on a UVB-induced skin cancer model to find an optimal dose and time for desirable chemopreventive effects. UVB radiation (30 mJ/cm(2), 5 days/week for 25 or 27 weeks) was used to induce skin carcinogenesis in SKH-1 mice. For the time-response experiment 30 μg honokiol in acetone was applied topically to the animals before the UVB exposure (30 min, 1 h, and 2 h) and after the UVB exposure (immediately, 30 min, and 1 h). Control groups were treated with acetone. For the dose-response study, animals were treated topically with acetone or honokiol (30, 45, and 60 μg) one hour before the UVB exposure. In the time-response experiment, honokiol inhibited skin tumor multiplicity by 49-58% while reducing tumor volumes by 70-89%. In the dose-response study, honokiol (30, 45, and 60 μg) significantly decreased skin tumor multiplicity by 36-78% in a dose-dependent manner, while tumor area was reduced by 76-94%. Honokiol (60 μg) significantly reduced tumor incidence by 40% as compared to control group. Honokiol applied in very low doses (30 μg) either before or after UVB radiation shows chemopreventive effects. Honokiol (30, 45, and 60 μg) prevents UVB-induced skin cancer in a dose-dependent manner. Honokiol can be an effective chemopreventive agent against skin cancer.

Impact of UV-B radiation on the digestive enzymes and immune system of larvae of Indian major carp Catla catla.

PubMed

Sharma, Jaigopal; Rao, Y Vasudeva; Kumar, S; Chakrabarti, Rina

2010-03-01

Ultraviolet radiation is a potent threat to the aquatic animals. Exposure to such stressor affects metabolic and immunological processes. The present investigation aims to study the effect of UV-B radiation on digestive enzymes and immunity of larvae of Catla catla. Larvae were exposed to ultraviolet-B (UV-B, 280-320 nm) radiation (145 microW/cm(2)) for three different exposure times of 5, 10 and 15 min on every other day. After 55 days, important digestive enzymes were assayed. For immunological study, lysozyme, glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) levels were measured. Then the fish were kept for one month without radiation and lysozyme level was measured. Protein concentration varied directly with the duration of exposure and was highest among fish that had received the 15 min UV-B irradiation. Significantly higher amylase, protease, trypsin and chymotrypsin activities were found in 5 min exposed fish compared to others. Lysozyme level was significantly higher in control group compared to the UV-B treated fish. The lysozyme level decreased with the increasing duration of UV-B radiation. When fish were kept without UV-B radiation for one month, lysozyme level was brought to the normal level in all treatments, except 15 min exposed fish. The GOT and GPT levels were significantly higher in the 15 min exposed group than others. The effects of UV-B radiation on the digestive physiology and immune system of catla have been clearly observed in the present study. The decreased enzyme activities in UV-B radiated fish results into improper digestion and poor growth.

Silibinin enhances the repair of ultraviolet B-induced DNA damage by activating p53-dependent nucleotide excision repair mechanism in human dermal fibroblasts

PubMed Central

Guillermo-Lagae, Ruth; Deep, Gagan; Ting, Harold; Agarwal, Chapla; Agarwal, Rajesh

2015-01-01

Ultraviolet radiation B (UVB) is the main cause of DNA damage in epidermal cells; and if not repaired, this DNA damage leads to skin cancer. In earlier studies, we have reported that natural flavonolignan silibinin exerts strong chemopreventive efficacy against UVB-induced skin damage and carcinogenesis; however mechanistic studies are still being actively pursued. Here, we investigated the role of nucleotide excision repair (NER) pathway in silibinin's efficacy to repair UVB-induced DNA damage. Normal human dermal fibroblasts (NHDFs) were exposed to UVB (1 mJ/cm2) with pre- or post- silibinin (100 μM) treatment, and cyclobutane pyrimidine dimers (CPDs) formation/repair was measured. Results showed that post-UVB silibinin treatment accelerates DNA repair via activating the NER pathway including the expression of XPA (xeroderma pigmentosum complementation group A), XPB, XPC, and XPG. In UVB exposed fibroblasts, silibinin treatment also increased p53 and GADD45α expression; the key regulators of the NER pathway and DNA repair. Consistently, post-UVB silibinin treatment increased the mRNA transcripts of XPA and GADD45α. Importantly, silibinin showed no effect on UVB-induced DNA damage repair in XPA- and XPB-deficient human dermal fibroblasts suggesting their key role in silibinin-mediated DNA damage repair. Moreover, in the presence of pifithrin-α, an inhibitor of p53, the DNA repair efficacy of silibinin was compromised associated with a reduction in XPA and GADD45α transcripts. Together, these findings suggest that silibinin's efficacy against UVB-induced photodamage is primarily by inhibiting NER and p53; and these findings further support silibinin's usage as a potential inexpensive, effective, and non-toxic agent for skin cancer chemoprevention. PMID:26447614

Silibinin enhances the repair of ultraviolet B-induced DNA damage by activating p53-dependent nucleotide excision repair mechanism in human dermal fibroblasts.

PubMed

Guillermo-Lagae, Ruth; Deep, Gagan; Ting, Harold; Agarwal, Chapla; Agarwal, Rajesh

2015-11-24

Ultraviolet radiation B (UVB) is the main cause of DNA damage in epidermal cells; and if not repaired, this DNA damage leads to skin cancer. In earlier studies, we have reported that natural flavonolignan silibinin exerts strong chemopreventive efficacy against UVB-induced skin damage and carcinogenesis; however mechanistic studies are still being actively pursued. Here, we investigated the role of nucleotide excision repair (NER) pathway in silibinin's efficacy to repair UVB-induced DNA damage. Normal human dermal fibroblasts (NHDFs) were exposed to UVB (1 mJ/cm2) with pre- or post- silibinin (100 μM) treatment, and cyclobutane pyrimidine dimers (CPDs) formation/repair was measured. Results showed that post-UVB silibinin treatment accelerates DNA repair via activating the NER pathway including the expression of XPA (xeroderma pigmentosum complementation group A), XPB, XPC, and XPG. In UVB exposed fibroblasts, silibinin treatment also increased p53 and GADD45α expression; the key regulators of the NER pathway and DNA repair. Consistently, post-UVB silibinin treatment increased the mRNA transcripts of XPA and GADD45α. Importantly, silibinin showed no effect on UVB-induced DNA damage repair in XPA- and XPB-deficient human dermal fibroblasts suggesting their key role in silibinin-mediated DNA damage repair. Moreover, in the presence of pifithrin-α, an inhibitor of p53, the DNA repair efficacy of silibinin was compromised associated with a reduction in XPA and GADD45α transcripts. Together, these findings suggest that silibinin's efficacy against UVB-induced photodamage is primarily by inhibiting NER and p53; and these findings further support silibinin's usage as a potential inexpensive, effective, and non-toxic agent for skin cancer chemoprevention.

Ultraviolet B radiation induces impaired lifecycle traits and modulates expression of cytochrome P450 (CYP) genes in the copepod Tigriopus japonicus.

PubMed

Puthumana, Jayesh; Lee, Min-Chul; Park, Jun Chul; Kim, Hui-Su; Hwang, Dae-Sik; Han, Jeonghoon; Lee, Jae-Seong

2017-03-01

To evaluate the effects of ultraviolet B (UV-B) radiation at the developmental, reproductive, and molecular levels in aquatic invertebrates, we measured UV-B-induced acute toxicity, impairments in developmental and reproductive traits, and UV-B interaction with the entire family of cytochrome P450 (CYP) genes in the intertidal benthic copepod Tigriopus japonicus. We found a significant, dose-dependent reduction (P<0.05) in the survival of T. japonicus that began as a developmental delay and decreased fecundity. The 48h LD10 and LD50 were 1.35 and 1.84kJ/m 2 , and the CYP inhibitor (PBO) elevated mortality, confirming the involvement of CYP genes in UV-B induced toxicity. Low-dose UV-B (1.5kJ/m 2 ) induced developmental delays, and higher doses (6-18kJ/m 2 ) caused reproductive impairments in ovigerous females. The significant up-regulation of CYP genes belonging to clans 2/3/MT/4/20 in T. japonicus exposed to UV-B (12kJ/m 2 ) confirmed molecular interaction between UV-B and CYP genes. Moreover, orphan CYPs, such as CYP20A1, provide good insight on the deorphanization of invertebrate CYPs. Overall, these results demonstrate the involvement of UV-B radiation in the expression of all the CYP genes in T. japonicus and their susceptibility to UV-B radiation. This will provide a better understanding of the mechanistic effects of UV-B in copepods through the predicted AhR-mediated up-regulation of CYP genes. Copyright © 2017 Elsevier B.V. All rights reserved.

Ultraviolet radiation properties as applied to photoclimatherapy at the Dead Sea.

PubMed

Kudish, A I; Abels, D; Harari, M

2003-05-01

The Dead Sea basin, the lowest terrestrial point on earth, is recognized as a natural treatment center for patients with various cutaneous and rheumatic diseases. Psoriasis is the major skin disease treated at the Dead Sea with excellent improvement to complete clearance exceeding 85% after 4 weeks of treatment. These results were postulated to be associated with a unique spectrum of ultraviolet radiation present in the Dead Sea area. The UVB and UVA radiation at two sites is measured continuously by identical sets of broad-band Solar Light Co. Inc. meters (Philadelphia, PA). The spectral selectivity within the UVB and UVA spectrum was determined using a narrow-band spectroradiometer, UV-Optronics 742 (Orlando, FL). The optimum exposure time intervals for photoclimatherapy, defined as the minimum ratio of erythema to therapeutic radiation intensities, were also determined using a Solar Light Co. Inc. Microtops II, Ozone Monitor-Sunphotometer. The ultraviolet radiation at the Dead Sea is attenuated relative to Beer Sheva as a result of the increased optical path length and consequent enhanced scattering. The UVB radiation is attenuated to a greater extent than UVA and the shorter erythema UVB spectral range decreased significantly compared with the longer therapeutic UVB wavelengths. It was demonstrated that the relative attenuation within the UVB spectral range is greatest for the shorter erythema rays and less for the longer therapeutic UVB wavelengths, thus producing a greater proportion of the longer therapeutic UVB wavelengths in the ultraviolet spectrum. These measurements can be utilized to minimize the exposure to solar radiation by correlating the cumulative UVB radiation dose to treatment efficacy and by formulating a patient sun exposure treatment protocol for Dead Sea photoclimatherapy.

Enzymatic recognition of DNA damage induced by UVB-photosensitized titanium dioxide and biological consequences in Saccharomyces cerevisiae: evidence for oxidatively DNA damage generation.

PubMed

Pinto, A Viviana; Deodato, Elder L; Cardoso, Janine S; Oliveira, Eliza F; Machado, Sérgio L; Toma, Helena K; Leitão, Alvaro C; de Pádula, Marcelo

2010-06-01

Although titanium dioxide (TiO(2)) has been considered to be biologically inert, finding use in cosmetics, paints and food colorants, recent reports have demonstrated that when TiO(2) is attained by UVA radiation oxidative genotoxic and cytotoxic effects are observed in living cells. However, data concerning TiO(2)-UVB association is poor, even if UVB radiation represents a major environmental carcinogen. Herein, we investigated DNA damage, repair and mutagenesis induced by TiO(2) associated with UVB irradiation in vitro and in vivo using Saccharomyces cerevisiae model. It was found that TiO(2) plus UVB treatment in plasmid pUC18 generated, in addition to cyclobutane pyrimidine dimers (CPDs), specific damage to guanine residues, such as 8-oxo-7,8-dihydroguanine (8-oxoG) and 2,6-diamino-4-hydroxy-5-formamidopyrimidine (FapyG), which are characteristic oxidatively generated lesions. In vivo experiments showed that, although the presence of TiO(2) protects yeast cells from UVB cytotoxicity, high mutation frequencies are observed in the wild-type (WT) and in an ogg1 strain (deficient in 8-oxoG and FapyG repair). Indeed, after TiO(2) plus UVB treatment, induced mutagenesis was drastically enhanced in ogg1 cells, indicating that mutagenic DNA lesions are repaired by the Ogg1 protein. This effect could be attenuated by the presence of metallic ion chelators: neocuproine or dipyridyl, which partially block oxidatively generated damage occurring via Fenton reactions. Altogether, the results indicate that TiO(2) plus UVB potentates UVB oxidatively generated damage to DNA, possibly via Fenton reactions involving the production of DNA base damage, such as 8-oxo-7,8-dihydroguanine. Copyright 2010 Elsevier B.V. All rights reserved.

Long non-coding RNA HOTAIR promotes UVB-induced apoptosis and inflammatory injury by up-regulation of PKR in keratinocytes.

PubMed

Liu, Guo; Zhang, Wenhao

2018-06-11

Excessive exposure to ultraviolet (UV) rays can cause damage of the skin and may induce cancer, immunosuppression, photoaging, and inflammation. The long non-coding RNA (lncRNA) HOX antisense intergenic RNA (HOTAIR) is involved in multiple human biological processes. However, its role in UVB-induced keratinocyte injury is unclear. This study was performed to investigate the effects of HOTAIR in UVB-induced apoptosis and inflammatory injury in human keratinocytes (HaCaT cells). Quantitative real-time polymerase chain reaction was performed to analyze the expression levels of HOTAIR, PKR, TNF-α, and IL-6. Cell viability was measured using trypan blue exclusion method and cell apoptosis using flow cytometry and western blot. ELISA was used to measure the concentrations of TNF-α and IL-6. Western blot was used to measure the expression of PKR, apoptosis-related proteins, and PI3K/AKT and NF-κB pathway proteins. UVB induced HaCaT cell injury by inhibiting cell viability and promoting cell apoptosis and expressions of IL-6 and TNF-α. UVB also promoted the expression of HOTAIR. HOTAIR suppression increased cell viability and decreased apoptosis and expression of inflammatory factors in UVB-treated cells. HOTAIR also promoted the expression of PKR. Overexpression of HOTAIR decreased cell viability and increased cell apoptosis and expression of inflammatory factors in UVB-treated cells by upregulating PKR. Overexpression of PKR decreased cell viability and promoted cell apoptosis in UVB-treated cells. Overexpression of PKR activated PI3K/AKT and NF-κB pathways. Our findings identified an essential role of HOTAIR in promoting UVB-induced apoptosis and inflammatory injury by up-regulating PKR in keratinocytes.

Dietary eicosapentaenoic acid prevents systemic immunosuppression in mice induced by UVB radiation.

PubMed

Moison, R M; Beijersbergen Van Henegouwen, G M

2001-07-01

Moison, R. M. W. and Beijersbergen van Henegouwen, G. M. J. Dietary Eicosapentaenoic Acid Prevents Systemic Immunosuppression in Mice Induced by UVB Radiation. Radiat. Res. 156, 36-44 (2001). Reactive oxygen species (ROS) contribute to the immunosuppression induced by UVB radiation. Omega-3 fatty acids in fish oil, e.g. eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), can modulate immunoresponsiveness, but because of their susceptibility to ROS-induced damage, they can also challenge the epidermal antioxidant defense system. The influence of dietary supplementation with different omega-3 fatty acids on systemic immunosuppression induced in mice by UVB radiation was studied using the contact hypersensitivity response to trinitrochlorobenzene. In an attempt to study the mechanisms involved, UVB-radiation-induced changes in epidermal antioxidant status were also studied. Mice received high-fat (25% w/w) diets enriched with either oleic acid (control diet), EPA, DHA, or EPA + DHA (MaxEPA). Immunosuppression induced by UVB radiation was 53% in mice fed the oleic acid diet and 69% in mice fed the DHA diet. In contrast, immunosuppression was only 4% and 24% in mice fed the EPA and MaxEPA diets, respectively. Increased lipid peroxidation and decreased vitamin E levels (P < 0.05) were found in unirradiated mice fed the MaxEPA and DHA diets. For all diets, exposure to UVB radiation increased lipid peroxidation (P < 0.05), but levels of glutathione (P < 0.05) and vitamin C (P > 0.05) decreased only in the mice given fish oil. UVB irradiation did not influence vitamin E levels. In conclusion, dietary EPA, but not DHA, protects against UVB-radiation-induced immunosuppression in mice. The degree of protection appears to be related to the amount of EPA incorporated and the ability of the epidermis to maintain an adequate antioxidant level after irradiation.

Effect of solar ultraviolet-B radiation during springtime ozone depletion on photosynthesis and biomass production of Antarctic vascular plants.

PubMed

Xiong, F S; Day, T A

2001-02-01

We assessed the influence of springtime solar UV-B radiation that was naturally enhanced during several days due to ozone depletion on biomass production and photosynthesis of vascular plants along the Antarctic Peninsula. Naturally growing plants of Colobanthus quitensis (Kunth) Bartl. and Deschampsia antarctica Desv. were potted and grown under filters that absorbed or transmitted most solar UV-B. Plants exposed to solar UV-B from mid-October to early January produced 11% to 22% less total, as well as above ground biomass, and 24% to 31% less total leaf area. These growth reductions did not appear to be associated with reductions in photosynthesis per se: Although rates of photosynthetic O(2) evolution were reduced on a chlorophyll and a dry-mass basis, on a leaf area basis they were not affected by UV-B exposure. Leaves on plants exposed to UV-B were denser, probably thicker, and had higher concentrations of photosynthetic and UV-B absorbing pigments. We suspect that the development of thicker leaves containing more photosynthetic and screening pigments allowed these plants to maintain their photosynthetic rates per unit leaf area. Exposure to UV-B led to reductions in quantum yield of photosystem II, based on fluorescence measurements of adaxial leaf surfaces, and we suspect that UV-B impaired photosynthesis in the upper mesophyll of leaves. Because the ratio of variable to maximal fluorescence, as well as the initial slope of the photosynthetic light response, were unaffected by UV-B exposure, we suggest that impairments in photosynthesis in the upper mesophyll were associated with light-independent enzymatic, rather than photosystem II, limitations.

Prevention of UVB Radiation-induced Epidermal Damage by Expression of Heat Shock Protein 70*

PubMed Central

Matsuda, Minoru; Hoshino, Tatsuya; Yamashita, Yasuhiro; Tanaka, Ken-ichiro; Maji, Daisuke; Sato, Keizo; Adachi, Hiroaki; Sobue, Gen; Ihn, Hironobu; Funasaka, Yoko; Mizushima, Tohru

2010-01-01

Irradiation with UV light, especially UVB, causes epidermal damage via the induction of apoptosis, inflammatory responses, and DNA damage. Various stressors, including UV light, induce heat shock proteins (HSPs) and the induction, particularly that of HSP70, provides cellular resistance to such stressors. The anti-inflammatory activity of HSP70, such as its inhibition of nuclear factor kappa B (NF-κB), was recently revealed. These in vitro results suggest that HSP70 protects against UVB-induced epidermal damage. Here we tested this idea by using transgenic mice expressing HSP70 and cultured keratinocytes. Irradiation of wild-type mice with UVB caused epidermal damage such as induction of apoptosis, which was suppressed in transgenic mice expressing HSP70. UVB-induced apoptosis in cultured keratinocytes was suppressed by overexpression of HSP70. Irradiation of wild-type mice with UVB decreased the cutaneous level of IκB-α (an inhibitor of NF-κB) and increased the infiltration of leukocytes and levels of pro-inflammatory cytokines and chemokines in the epidermis. These inflammatory responses were suppressed in transgenic mice expressing HSP70. In vitro, the overexpression of HSP70 suppressed the expression of pro-inflammatory cytokines and chemokines and increased the level of IκB-α in keratinocytes irradiated with UVB. UVB induced an increase in cutaneous levels of cyclobutane pyrimidine dimers and 8-hydroxy-2′-deoxyguanosine, both of which were suppressed in transgenic mice expressing HSP70. This study provides genetic evidence that HSP70 protects the epidermis from UVB-induced radiation damage. The findings here also suggest that the protective action of HSP70 is mediated by anti-apoptotic, anti-inflammatory, and anti-DNA damage effects. PMID:20018843

Sensitivity and Acclimation of Three Canopy-Forming Seaweeds to UVB Radiation and Warming

PubMed Central

Xiao, Xi; de Bettignies, Thibaut; Olsen, Ylva S.; Agusti, Susana; Duarte, Carlos M.; Wernberg, Thomas

2015-01-01

Canopy-forming seaweeds, as primary producers and foundation species, provide key ecological services. Their responses to multiple stressors associated with climate change could therefore have important knock-on effects on the functioning of coastal ecosystems. We examined interactive effects of UVB radiation and warming on juveniles of three habitat-forming subtidal seaweeds from Western Australia–Ecklonia radiata, Scytothalia dorycarpa and Sargassum sp. Fronds were incubated for 14 days at 16–30°C with or without UVB radiation and growth, health status, photosynthetic performance, and light absorbance measured. Furthermore, we used empirical models from the metabolic theory of ecology to evaluate the sensitivity of these important seaweeds to ocean warming. Results indicated that responses to UVB and warming were species specific, with Sargassum showing highest tolerance to a broad range of temperatures. Scytothalia was most sensitive to elevated temperature based on the reduced maximum quantum yields of PSII; however, Ecklonia was most sensitive, according to the comparison of activation energy calculated from Arrhenius’ model. UVB radiation caused reduction in the growth, physiological responses and thallus health in all three species. Our findings indicate that Scytothalia was capable of acclimating in response to UVB and increasing its light absorption efficiency in the UV bands, probably by up-regulating synthesis of photoprotective compounds. The other two species did not acclimate over the two weeks of exposure to UVB. Overall, UVB and warming would severely inhibit the growth and photosynthesis of these canopy-forming seaweeds and decrease their coverage. Differences in the sensitivity and acclimation of major seaweed species to temperature and UVB may alter the balance between species in future seaweed communities under climate change. PMID:26630025

Sensitivity and Acclimation of Three Canopy-Forming Seaweeds to UVB Radiation and Warming.

PubMed

Xiao, Xi; de Bettignies, Thibaut; Olsen, Ylva S; Agusti, Susana; Duarte, Carlos M; Wernberg, Thomas

2015-01-01

Canopy-forming seaweeds, as primary producers and foundation species, provide key ecological services. Their responses to multiple stressors associated with climate change could therefore have important knock-on effects on the functioning of coastal ecosystems. We examined interactive effects of UVB radiation and warming on juveniles of three habitat-forming subtidal seaweeds from Western Australia-Ecklonia radiata, Scytothalia dorycarpa and Sargassum sp. Fronds were incubated for 14 days at 16-30°C with or without UVB radiation and growth, health status, photosynthetic performance, and light absorbance measured. Furthermore, we used empirical models from the metabolic theory of ecology to evaluate the sensitivity of these important seaweeds to ocean warming. Results indicated that responses to UVB and warming were species specific, with Sargassum showing highest tolerance to a broad range of temperatures. Scytothalia was most sensitive to elevated temperature based on the reduced maximum quantum yields of PSII; however, Ecklonia was most sensitive, according to the comparison of activation energy calculated from Arrhenius' model. UVB radiation caused reduction in the growth, physiological responses and thallus health in all three species. Our findings indicate that Scytothalia was capable of acclimating in response to UVB and increasing its light absorption efficiency in the UV bands, probably by up-regulating synthesis of photoprotective compounds. The other two species did not acclimate over the two weeks of exposure to UVB. Overall, UVB and warming would severely inhibit the growth and photosynthesis of these canopy-forming seaweeds and decrease their coverage. Differences in the sensitivity and acclimation of major seaweed species to temperature and UVB may alter the balance between species in future seaweed communities under climate change.

C/EBPα regulates CRL4Cdt2-mediated degradation of p21 in response to UVB-induced DNA damage to control the G1/S checkpoint

PubMed Central

Hall, Jonathan R; Bereman, Michael S; Nepomuceno, Angelito I; Thompson, Elizabeth A; Muddiman, David C; Smart, Robert C

2014-01-01

The bZIP transcription factor, C/EBPα is highly inducible by UVB and other DNA damaging agents in keratinocytes. C/EBPα-deficient keratinocytes fail to undergo cell cycle arrest in G1 in response to UVB-induced DNA damage and mice lacking epidermal C/EBPα are highly susceptible to UVB-induced skin cancer. The mechanism through which C/EBPα regulates the cell cycle checkpoint in response to DNA damage is unknown. Here we report untreated C/EBPα-deficient keratinocytes have normal levels of the cyclin-dependent kinase inhibitor, p21, however, UVB-treated C/EBPα-deficient keratinocytes fail to up-regulate nuclear p21 protein levels despite normal up-regulation of Cdkn1a mRNA levels. UVB-treated C/EBPα-deficient keratinocytes displayed a 4-fold decrease in nuclear p21 protein half-life due to the increased proteasomal degradation of p21 via the E3 ubiquitin ligase CRL4Cdt2. Cdt2 is the substrate recognition subunit of CRL4Cdt2 and Cdt2 mRNA and protein levels were up-regulated in UVB-treated C/EBPα-deficient keratinocytes. Knockdown of Cdt2 restored p21 protein levels in UVB-treated C/EBPα-deficient keratinocytes. Lastly, the failure to accumulate p21 in response to UVB in C/EBPα-deficient keratinocytes resulted in decreased p21 interactions with critical cell cycle regulatory proteins, increased CDK2 activity, and inappropriate entry into S-phase. These findings reveal C/EBPα regulates G1/S cell cycle arrest in response to DNA damage via the control of CRL4Cdt2 mediated degradation of p21. PMID:25483090

The Effect of K+ on Caspase Activity of Corneal Epithelial Cells Exposed to UVB

PubMed Central

Leerar, John R.; Glupker, Courtney D.; Schotanus, Mark P.; Ubels, John L.

2016-01-01

Exposure of human corneal limbal epithelial (HCLE) cells to UVB triggers rapid loss of K+ and apoptosis via activation of caspases-9, -8 and -3. It has been shown that preventing loss of intracellular K+ can inhibit apoptosis. The goal of this study was to investigate the effect of K+ on the UVB-induced caspase activity. HCLE cells were exposed to 150 mJ/cm2 UVB, followed by measurement of caspase activity in cell lysates. Caspase activity was measured in the presence and absence of 100 mM K+ in the reaction buffer. UVB-induced activity of caspases-9, -8 and -3 all decreased in the presence of 100 mM K+. These results suggest that a role of high [K+] in the cell is to inhibit caspase activity. Therefore, when cells lose K+ in response to UVB, caspases are activated and cells go into apoptosis. This supports our hypothesis that K+ inhibits caspase activity. PMID:27456133

Myricetin suppresses UVB-induced wrinkle formation and MMP-9 expression by inhibiting Raf

PubMed Central

Jung, Sung Keun; Lee, Ki Won; Kim, Ho Young; Oh, Mi Hyun; Byun, Sanguine; Lim, Sung Hwan; Heo, Yong-Seok; Kang, Nam Joo; Bode, Ann M.; Dong, Zigang; Lee, Hyong Joo

2010-01-01

Chronic exposure to solar ultraviolet (UV) light causes skin photoaging. Many studies have shown that naturally occurring phytochemicals have anti-photoaging effects, but their direct target molecule(s) and mechanism(s) remain unclear. We found that myricetin, a major flavonoid in berries and red wine, inhibited wrinkle formation in mouse skin induced by chronic UVB irradiation (0.18 J/cm2, 3 days/wk for 15 wk). Myricetin treatment reduced UVB-induced epidermal thickening of mouse skin and also suppressed UVB-induced matrix metalloproteinase-9 (MMP-9) protein expression and enzyme activity. Myricetin appeared to exert its anti-aging effects by suppressing UVB-induced Raf kinase activity and subsequent attenuation of UVB-induced phosphorylation of MEK and ERK in mouse skin. In vitro and in vivo pull-down assays revealed that myricetin bound with Raf in an ATP-noncompetitive manner. Overall, these results indicate that myricetin exerts potent anti-photoaging activity by regulating MMP-9 expression through the suppression of Raf kinase activity. PMID:20093107

Long-term exposure to enhanced UV-B radiation has no significant effects on growth or secondary compounds of outdoor-grown Scots pine and Norway spruce seedlings.

PubMed

Turtola, Satu; Sallas, Leena; Holopainen, Jarmo K; Julkunen-Tiitto, Riitta; Kainulainen, Pirjo

2006-11-01

The effects of long-term enhanced UV-B radiation on growth and secondary compounds of two conifer species were studied in an outdoor experiment. Scots pine (Pinus sylvestris) seedlings were exposed for two growing seasons and Norway spruce (Picea abies) seedlings for three growing seasons to supplemental UV-B radiation, corresponding to a 30% increase in ambient UV-B radiation. The experiment also included appropriate controls for ambient and increased UV-A radiation. Enhanced UV-B did not affect the growth of the conifer seedlings. In addition, neither the concentrations of terpenes and phenolics in the needles nor the concentrations of terpenes in the wood were affected. However, in the UV-A control treatment the concentrations of diterpenes in the wood of Scots pine decreased significantly compared to the ambient control. Apparently, a small increase in UV-B radiation has no significant effects on the secondary compounds and growth of Scots pine and Norway spruce seedlings.

Protective Effect of the Ethyl Acetate Fraction of Sargassum muticum Against Ultraviolet B–Irradiated Damage in Human Keratinocytes

PubMed Central

Piao, Mei Jing; Yoon, Weon Jong; Kang, Hee Kyoung; Yoo, Eun Sook; Koh, Young Sang; Kim, Dong Sam; Lee, Nam Ho; Hyun, Jin Won

2011-01-01

The aim of this study was to investigate the cytoprotective properties of the ethyl acetate fraction of Sargassum muticum (SME) against ultraviolet B (UVB)-induced cell damage in human keratinocytes (HaCaT cells). SME exhibited scavenging activity toward the 1,1-diphenyl-2-picrylhydrazyl radicals and hydrogen peroxide (H2O2) and UVB-induced intracellular reactive oxygen species (ROS). SME also scavenged the hydroxyl radicals generated by the Fenton reaction (FeSO4 + H2O2), which was detected using electron spin resonance spectrometry. In addition, SME decreased the level of lipid peroxidation that was increased by UVB radiation, and restored the level of protein expression and the activities of antioxidant enzymes that were decreased by UVB radiation. Furthermore, SME reduced UVB-induced apoptosis as shown by decreased DNA fragmentation and numbers of apoptotic bodies. These results suggest that SME protects human keratinocytes against UVB-induced oxidative stress by enhancing antioxidant activity in cells, thereby inhibiting apoptosis. PMID:22174656