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Metrologia ◽  
2022 ◽  
Author(s):  
Jeanne M Houston ◽  
Clarence Zarobila ◽  
Howard W Yoon

Abstract Improvements in a lamp-monochromator-based facility at the National Institute of Standards and Technology (NIST), the Visible near-infrared Spectral Comparator Facility (VisSCF) which is used to calibrate optical detectors for spectral radiant power responsivity from 300 nm to 1100 nm, are described. These changes include extending the VisSCF operational range down to 300 nm from 350 nm, thereby fully covering the ultraviolet-A (UVA) spectral region and partially covering the UVB range. These improvements have lowered the magnitudes of most of the components in the uncertainty budget and have led to combined 0.005 % transfer (k=1) uncertainties in the spectral power responsivity calibrations over most of the spectral range. Redevelopment of the uncertainty budget results in total expanded uncertainties of spectral responsivities of less than 0.1 % (k=2) over the spectral range from 380 nm to 980 nm, with the greatest uncertainty term coming from the calibrations of the transfer standards.


2021 ◽  
Vol 97 (5) ◽  
pp. 26-37
Author(s):  
A. E. Karamova ◽  
V. V. Chikin ◽  
A. A. Kubanov ◽  
L. K. Davletbaeva

One of the methods of therapy for atopic dermatitis is long-wavelength ultraviolet therapy A (UVA-1- therapy). This review aims to provide the mechanisms of action of UVA-1-therapy an overview about the effectiveness of UVA-1-therapy in patients with atopic dermatitis taking into account factors that can affect the effectiveness of treatment radiation dose, skin phototype of patients, concomitant drug therapy. The available data on a decrease in the severity of atopic dermatitis as a result of the course of UVA-1-therapy and on a decrease in the severity of itching in patients are presented. The data on the rate of onset of the therapeutic effect of UVA-1-therapy and the duration of its maintenance are considered. The safety of UVA-1-therapy is discussed, and the most frequent undesirable effects a feeling of warmth, fever, itching, hyperpigmentation, are given. The possibility of developing side effects requiring discontinuation of treatment is assessed. The data obtained indicate the effectiveness and safety of the UFA-1-radiation in the treatment of patients with moderate-to-severe atopic dermatitis.


2021 ◽  
Vol 12 ◽  
Author(s):  
Fausta Natella ◽  
Barbara Guantario ◽  
Roberto Ambra ◽  
Giulia Ranaldi ◽  
Federica Intorre ◽  
...  

Hamamelis virginiana L. a rich source of both condensed and hydrolyzable tannins, utilized to treat dermatological disorders. Since no experimental and clinical data is available for its use as oral formulation in skin related disorders, the purpose of this study was to investigate the effects of Hamaforton™ (Hamamelis virginiana extract) metabolites on gene dysregulation induced by ultraviolet A radiation in cultured human dermal fibroblasts. A combination of in vivo and ex vivo experimental designs has been exploited in order to take into account the polyphenol metabolic transformation that occurs in humans. 12 healthy volunteers received either a capsule of Hamaforton™ or a placebo in a randomized, blinded crossover trial. After Hamaforton™ ingestion, the kinetic of appearance of galloyl derivatives was measured in plasma. Then, in the ex vivo experiment, the serum isolated after supplementation was used as a source of Hamaforton™ metabolites to enrich the culture medium of dermal fibroblasts exposed to ultraviolet A radiation. Three different gallic acid metabolites (4-O-methyl gallic acid, 4-O-methyl gallic acid sulphate and trimethyl gallic acid glucuronide) were identified in volunteer plasma. While, ultraviolet A irradiation of dermal fibroblasts affected the expression of extracellular matrix genes, the presence of Hamaforton™ metabolites in the culture media did not affect the expression of most of those genes. However, the activation of the expression of 10 different genes involved in repair processes for the maintenance of skin integrity, suggest that the metabolites can play a role in damage recovery. To our knowledge, this is the first study that demonstrates the bioavailability of Hamaforton™ phenolic compounds, and the effects of its metabolites on cultured dermal fibroblast response to ultraviolet A irradiation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hellen Paula Valerio ◽  
Felipe Gustavo Ravagnani ◽  
Graziella Eliza Ronsein ◽  
Paolo Di Mascio

AbstractEpidermal photoaging contributes to skin fragility over time and it is a risk factor for skin cancer. Photoaging has been associated for a long time with exposure to Ultraviolet-A (UVA) light, the predominant component of the solar ultraviolet radiation. While the cellular mechanisms underlying UVA-induced photoaging in the dermis have been well characterized, UVA’s action on the epidermis remains elusive. Here, proteomic analysis was conducted to derive the cellular responses induced by an environmentally relevant dose of UVA in primary human keratinocytes. We also investigated the effects of UVA on non-transformed immortalized keratinocytes (HaCaT cells), bearing potentially oncogenic mutations. We showed that UVA induces proteome remodeling and senescence in primary keratinocytes, eliciting potent antioxidant and pro-inflammatory responses. Additionally, we showed that UVA modulates the secretory phenotype of these cells to the extent of inducing paracrine oxidative stress and immune system activation in pre-malignant keratinocytes. These observations offer insights into the cellular mechanisms by which UVA drives photoaging in the skin.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 2462-2462
Author(s):  
Serena Rupoli ◽  
Gaia Goteri ◽  
Erika Morsia ◽  
Elena Torre ◽  
Kimberly Blaine Garvey ◽  
...  

Abstract Introduction: Patients with early stage Cutaneous T cell Lymphoma (CTCL) usually have a benign and chronic disease course. Refractoriness under skin directed therapies and/or more extensive disease pose some therapeutic changes. Using the combination of psoralen plus ultraviolet A irradiation (PUVA) and low-dose Interferon-α (INF), the principal treatment goal is to keep confined the disease to the skin, preventing disease progression. Methods: We carry out a prospective data on 87 patients with early stage IA to IIA MF treated with low-dose IFN-α2b and PUVA, enrolled from 1997 to 2010. We collected data regarding clinical characteristics of MF, efficacy and outcome. Subcutaneous IFN-α2b was administered 1.5 MU/day during the first week; in the second week the dose was increased to 3MU/day. PUVA irradiation was started on the 3th week with IFN-α2b 3 MU 3 times weekly until CR, of for a maximum of 2 months. During maintenance therapy, IFN-α2b was scheduled for 3 MU 3 times weekly for 2 months and subsequently 3 MU 2 times weekly for 10 months and PUVA was gradually reduced every 2 months over a period of 12 months. Diagnostic, risk and response assignments were according to EORTC criteria. Results: Patient characteristics at time diagnosis, staging, response rates and overall outcome are shown in Table 1. Among the 87 patients, overall response rate (ORR) was 97.8% (n=85) and included complete remission (CR) in 70 patients (80.5%), very good partial remission in 5 patients (5.8%) and partial remission (PR) in another 10 (11.5%). The best response to therapy was seen after a median of 5 months (range, 1-30) and the 74.3% of patients who achieved a CR after induction therapy kept the complete response at the last follow up. Among the responders, 40 (47.1%) relapsed with minor event with in median time of 21 months (range, 0-71) and 7(8.2%) relapsed with major event in a median time of 6 months (range, 1-81). After a median follow up of 207 months (range, 6-295), 25 (28.7) patients died, only 1 for progressive disease. Median overall survival (OS) for our cohort was not reached (95% CI; 235-NR months) and median time to next treatment (TTNT) was 38.5 months (95% CI, 33-46 months). Moreover, disease free survival (DFS) in CR patients was 210 months (95% CI; 200-226 months). Conclusions: The long follow up of this study verifies our preliminary results and confirms the efficacy of INF-PUVA combination therapy in a real world setting, according conventional (OS and DFS) and emerging (TTNT) clinical endpoints of treatment efficacy. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.


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