Optimal Fluence and Duration of Low-Level Laser Therapy for Efficient Wound Healing in Mice.

BACKGROUND: Low-level laser (light) therapy is a promising technology that stimulates healing, relieves pain and inflammation, and restores function in injured body parts. However, few studies have compared the effects of light-emitting diodes of different fluence levels or different treatment durations. OBJECTIVE: Here, we investigated the effects of various fluence levels and treatment durations on wound closure in mice. METHODS: Full-thickness wounds were created on the dorsal skin using an 8-mm diameter punch, and the wounds were irradiated at 1, 4, or 40 J/cm2 for 5 consecutive days starting on day 1. To determine the optimal irradiation duration, wounds were irradiated at the most potent fluence of previous study for 5, 10, or 15 days. Photographic documentation, skin biopsies, and wound measurements were performed to compare the effects of different treatment parameters. RESULTS: The most effective fluence level was 40 J/cm2 at day 5, as determined by monitoring wound closure. There were no statistically significant differences in wound healing with different durations. CONCLUSION: We have shown that repeated exposure to low levels of light significantly stimulates wound healing in mice and demonstrated more efficient wound closure with certain fluences of 830 nm irradiation.

Risk factors for feelings of sadness and suicide attempts among cancer survivors in South Korea: findings from nationwide cross-sectional study (KNHANES IV-VI).

INTRODUCTION: As the number of cancer survivors is rapidly increasing with the increased incidence of the disease and improved survival of patients, the prevalence of, and risk factors for, mental health problems and suicidality among cancer survivors should be examined. METHODS AND ANALYSIS: Using data obtained from the Korean National Health and Nutrition Examination Survey (2007-2013), we examined 1285 and 33 772 participants who had been and never been diagnosed with cancer, respectively. We investigated the risks of feelings of sadness and suicide attempts among cancer survivors and general population and examined differences in the risks of cancer survivors among subgroups according to cancer-related characteristics. RESULTS: The median age of survivors at the time of the survey and at diagnosis was 63 and 54 years, respectively. After adjusting for sex, level of education, household income, occupation, marital status, cancer type, current status of treatment, age at diagnosis and years since diagnosis, the risk of suicide attempts was significantly higher in participants diagnosed with cancer before 45 years of age compared with those diagnosed at 45-64 years (adjusted OR=3.81, 95% CI 1.07 to 13.60, P=0.039), and the higher risk of suicide attempts with borderline significance was found in those for whom more than 10 years had passed since diagnosis compared with those for whom the diagnosis was made only 2-10 years ago (adjusted OR=3.38, 95% CI 0.98 to 11.70, P=0.055). However, feelings of sadness were not significantly associated with any cancer-related characteristic. CONCLUSION: Our results reveal an increased risk of suicide attempts among cancer survivors diagnosed early in life and in those for whom more than 10 years has passed since the diagnosis, suggesting the need for intensive monitoring and support for mental health problems and suicidal risks in this population.

Combined use of botulinum toxin type A and B for forehead rhytides: a randomized, double-blind, split-face study.

BACKGROUND: This is the first well-controlled study of the combined use of botulinum toxin type A (BoNT-A) and botulinum toxin type B (BoNT-B) for hyperkinetic lines in forehead. OBJECTIVE: To evaluate the effectiveness and safety of a mixture of BoNT-A and BoNT-B with that of equipotent BoNT-A alone for treating patients with forehead rhytides. MATERIALS AND METHODS: Fourteen patients with forehead wrinkles completed this clinical study. On day 0, patients received a mixture of BoNT-A (5 U) and B (500 U) on one side of the forehead and BoNT-A (10 U) symmetrically on the other side. Clinical evaluation was made at the beginning and at weeks 1, 2, 4, 8, 12, and 16. Therapeutic efficacy was evaluated using clinical improvement scale by investigators and the subjective wrinkle assessment by patients. RESULTS: According to investigator assessment, the differences between the average improvement scores of the two differently treated sides were not statistically significant at all follow-up visits. Moreover, the plateau of the clinical benefit was achieved at week 4. CONCLUSION: We observed the equivalent efficacy in the mixture of both toxins and BoNT-A alone.

Pigmentation above the constitutive level: an indicator of excimer laser radiation-induced erythema in Koreans.

Ultraviolet (UV) irradiation induces skin erythema, but it is not clear which factors have the greatest effects on UV sensitivity. Six healthy Korean adult men were enrolled and their melanin index (MI) and increment of erythema index (ΔEI) were measured. In each individual, 12 different sites were selected and 36 spots were irradiated with a single shot of monochromatic excimer laser with a dose of 350 mJ/cm(2) . The sites were categorized into three groups based on the cumulative sun exposure: UZ, unexposed zones; FEZ, frequently exposed zones; and IEZ, intermittently exposed zones. The sun exposure indexes (SEI) were also calculated based on previously described methods. ΔEI, MI and SEI were measured and calculated. The ΔEI of UZ was significantly higher than that of FEZ, but lower than that of IEZ. In general, there was a significant relationship between ΔEI and MI (R(2) = 0.135). However, IEZ did not show significant results. In contrast, there was a stronger relationship between ΔEI and SEI (R(2) = 0.344). Overall, the values were significantly higher for the SEI (0.541 [UZ], 0.281 [IEZ] and 0.228 [FEZ]) than for MI (0.311 [UZ], 0.011 [IEZ] and 0.073 [FEZ]). There were significant site variations in UV sensitivity along with skin pigmentation. In addition, significant differences were observed according to the exposure frequency. The SEI was found to be strongly correlated with UV sensitivity. These results suggest that the induced level of pigmentation above the constitutive level will be a better indicator for UV sensitivity than baseline MI.

Effects of murine dermal cells on the regulation of hair growth is dependent on the cell number and post-natal age of newborn mice.

Dermal cells from neonatal mice can initiate the formation of hair follicles (HFs) when combined with adult mouse epidermal cells and transplanted subcutaneously into athymic mice. In the present study, the effects of dermal cells on HF formation were tested in terms of total cell number and the time course of cell harvest. Results demonstrated that the number of dermal cells is critical to the formation of HF. Furthermore, hair forming ability is rapidly decreasing as the neonatal mice age. To examine potential differences in gene expression, cDNA array was performed. Results demonstrate that numerous molecules which are directly involved in receptor and signaling correlated with decreased hair inductivity in early time points after delivery. It is reported that bone morphogenic protein (BMP)-6 and Wnt3a treatment increased hair inductivity of dermal papilla cells. But in our study, no changes were observed in the expression levels of BMP-6 and Wnt3a. However, several Wnt related genes demonstrate increased or decreased expression levels. Thus, our results suggest that co-ordinated regulation of these molecules will be important in hair neogenesis within our model system.

Novel anti-inflammatory peptides as cosmeceutical peptides.

Ultraviolet (UV) radiation induced inflammation plays an important role in the aging of human skin. Prostaglandin (PG) E(2) is the primary mediator of UVB induced photoinflammation. We screened an internal library for dipeptides that inhibited UVB induced PGE(2) synthesis but showed no cytotoxicity toward human keratinocytes. We identified three highly active inhibitory sequences, LE (Leu+Glu), MW (Met+Trp) and MY (Met+Tyr). To evaluate their efficacy in human skin, 24 sites of abdomen skin were irradiated with a 308 nm excimer laser (300 mJ/cm(2)), after which 2% LE, MW, MY or a control were applied to the irradiated sites for 24h. The erythema index (EI) was measured before and 24h after treatment. The results showed that LE and MW significantly decreased UVB induced erythema (p=0.041 and p=0.036, respectively), but ME did not. Overall, LE and MW are candidate cosmeceutical peptides that can protect skin from UVB induced photoinflammation.

Rapid healing and reduced erythema after ablative fractional carbon dioxide laser resurfacing combined with the application of autologous platelet-rich plasma.

BACKGROUND: Fractional carbon dioxide laser resurfacing (FxCR) has shown considerable efficacy in reducing wrinkles, although complications such as scarring and prolonged erythema are more common and down-time is longer than with nonablative laser treatment. Platelet-rich plasma (PRP), a high concentration of platelets in a small volume of plasma, is known to enhance tissue healing. OBJECTIVE: To evaluate the benefits of PRP in the wound healing process after FxCR. MATERIALS AND METHODS: Twenty-five subjects were treated with FxCR on the bilateral inner arms. PRP was prepared from 10 mL of whole blood and applied on a randomly allocated side, with normal saline being used as the contralateral control. Transepidermal water loss (TEWL) and skin color were measured on both sides. Skin biopsies were also taken from five subjects on day 28. RESULTS: Significantly faster recovery of TEWL was seen on the PRP-treated side. The erythema index and melanin index on the PRP-treated side were lower than on the control side. Biopsy specimens from the PRP-treated side showed thicker collagen bundles than those from the control side. CONCLUSION: Application of autologous PRP is an effective method for enhancing wound healing and reducing transient adverse effects after FxCR treatment.

Objective evaluation of photoepilation by phototrichogram.

Photoepilation is one of the most popular cosmetic procedures. However, there has been no objective method to evaluate the efficacy of hair removal. The goal of this study is to evaluate the effect of photoepilation more objectively using a phototrichogram method. Thirteen young, healthy, female volunteers were enrolled in this study. At initial work-up, semi-permanent tattoos were marked in both axillae of all the volunteers and hair variables were evaluated by phototrichogram and digital camera. Intense pulsed light-assisted photoepilations were performed in both axillae of the volunteers twice at 4-week intervals. At each visit, dermatologists checked changes of hair parameters. Clinically, 8 weeks after two treatments, hair reduction of all patients was achieved. Total hair counts, changes of anagen ratio, non-vellus hair counts, hair density, anagen growth rate and hair diameter were decreased sequentially and the reduction was statistically significant. No correlations were found between power, pain, patient and doctor evaluations at 4 weeks. Doctor evaluations correlated with anagen hair counts, anagen/total hair ratio, anagen/telogen ratio and total growth rate. Using phototrichograms could be an objective evaluation technique for hair removal. Anagen parameters and total growth rate of hairs in phototrichograms may be able to be predictable values for evaluating epilation.

Low-dose 1064-nm Q-switched Nd:YAG laser for the treatment of melasma.

BACKGROUND: Melasma is a common acquired pigmentary disorder which is sometimes hard to treat with conventional methods. Various kinds of modalities have been applied for the treatment of melasma but none shows constantly good results. OBJECTIVES: In this study, we would like to know the effect of low-dose 1064-nm Q-switched Nd:YAG laser (QSNYL) on melasma and want to evaluate the changes of skin after laser treatment. METHODS: Twenty melasma patients were enrolled. Two regions were evaluated from each patient; a total of 40 sites. The 1064-nm QSNYL at fluences of 2.0-3.5 J/cm(2) was used to treat the whole face, including the melasma lesions. The fluence was adjusted individually and increased until erythema was developed on the laser-treated area. The treatment was performed five times with a 1-week interval. Non-invasive measuring methods, including a chromatometer, mexameter, cutometer, visioscan and a corneometer, were used before and after treatment. RESULTS: The L-value from the chromatometer, which reflects the lightness of skin, was increased (0.86 +/- 1.67, p < 0.05). The melanin index from the mexameter was significantly decreased (-28.23 +/- 28.21, p < 0.001). The SEw value from the visioscan, which reflects the degree of wrinkling, decreased (-5.80 +/- 0.59, p = 0.040). None of the other measurement parameters showed significant changes. CONCLUSIONS: Low-dose 1064-nm QSNYL appears to be an effective treatment modality for melasma.