Evaluation of nail surface topography using a three-dimensional in vivo optical skin imaging system.

BACKGROUND: The analysis of nail surface topography is a subject of ever-increasing interest in dermatology, especially in cosmetic studies. However, there is no accurate and scientifically sound instrumental method that can identify and provide quantitative data on nail surface topography. MATERIALS AND METHODS: The right index fingers of 78 healthy individuals were examined. The severity of nail roughness was rated by two independent dermatologists on a scale of 1 to 3. Using the phaseshift rapid in vivo measurement of the skin (PRIMOS) system, three-dimensional microtopography was performed, and the roughness parameter values were calculated and evaluated. The relationship between clinical nail roughness grade and nail roughness parameter values obtained utilizing PRIMOS was evaluated. RESULTS: A moderate correlation was found between the roughness parameter values and the clinical roughness grade. Our study showed that an overall relationship exists between the nail roughness parameter values obtained using PRIMOS and clinically observed nail surface changes. CONCLUSION: With further studies, PRIMOS could be a valuable tool for clinicians and researchers for conducting an accurate and objective patient assessment in daily practice and demonstrating effectiveness of different therapies for nail dystrophy or evaluating cosmetic effects of various topical treatments in future clinical trials.

Mechanism and clinical applications of needle-free injectors in dermatology: Literature review.

BACKGROUND: Needle-free jet injectors are devices that deliver drugs using a high-speed jet without a needle. Recent studies have significantly increased our understanding of the mechanisms of needle-free jet injectors, and technical advancements have broadened the scope of application of the device. AIMS: We aimed to provide an up-to-date review of previous literature regarding the mechanism of action and clinical applications of needle-free jet injectors in dermatology field. METHODS: We conducted a PUBMED search for studies on needle-free jet injectors using the following parameters: "Pneumatic injector" OR "needleless injector" OR "needle-free injector" OR "jet injector." Among 191 results, 72 articles focusing on their mechanisms of action, cutaneous delivery patterns, and clinical applications in dermatology were selected for review. RESULTS: Significant clinical evidence has been published confirming the potential of needle-free jet injectors in treating various dermatologic conditions. In particular, these devices have the potential to be used in various skin remodeling treatment, especially in skin rejuvenation procedures by injecting various esthetic materials. CONCLUSION: As proven by accumulated experience, the applications of NFJIs are not restricted to vaccine or insulin delivery in dermatology field. However, this literature review shows that until now, there are no clinical guidelines that standardize the optimal parameters when using NFJIs on various clinical settings. Therefore, further studies should be performed in order to investigate the full potential of these devices in dermatology, to ensure safe and effective outcomes in clinical practice.

In vivo evaluation of novel particle-free polycaprolactone fillers for safety, degradation, and neocollagenesis in a rat model.

Dermal fillers have become popular due to the increased demand for skin rejuvenation products. Polycaprolactone (PCL), a newly developed bioresorbable medical polymer, has emerged as a durable and safe dermal filler. However, available PCL fillers cause irritation; carrier gels can coagulate PCL particles, block the injection needle, and cause nonhomogeneity of particle suspensions that could be responsible for the observed side effects. To relieve pain, premixing PCL filler with lidocaine. However, this formulation changes the property of the CMC portion of the PCL filler, and possibly results in an uneven suspension of the PCL particles. Hence, a particle-free PCL homogeneously solubilized in water was developed to overcome these limitations. This study aimed to assess the in vivo safety, biodegradability, and neocollagenesis ability of a novel PCL filler, DLMR01 using a rat model. Fillers were characterized after injecting a vehicle control or DLMR01 using a digital camera, folliscope, and a three-dimensional profiling system. Biopsy was performed to evaluate biocompatibility and neocollagenesis. Skin elasticity was measured using a Cutometer. DLMR01 caused no needle occlusion by particle aggregation or laborious injectability. Filler nodules dispersed to surrounding tissues within 6 hours without further granuloma formation. Histological inspection revealed no tissue residual material or foreign body reaction during the 12-week test period. DLMR01 increased dermal thickness, collagen regeneration, and skin elasticity. In conclusion, this study demonstrates the potential of DLMR01 for dermal rejuvenation in a rat model.

Efficacy and Safety of a Novel Botulinum Toxin A for Masseter Reduction: A Randomized, Double-Blind, Placebo-Controlled, Optimal Dose-Finding Study.

BACKGROUND: A wide lower face and a square jaw are considered esthetic problems, particularly in Asia. OBJECTIVE: To investigate the optimal dose of a novel botulinum toxin (prabotulinum toxin A) for treating masseteric hypertrophy. METHODS: Ninety subjects with masseteric hypertrophy were randomly divided into 5 groups and treated with placebo (A, normal saline) or prabotulinum toxin A (B: 24, C: 48, D: 72, and E: 96 units). Photography, ultrasonography, and 3-dimensional imaging were performed before and after injection at baseline and at 4, 8, 12, and 16 weeks after treatment. The participants also rated their satisfaction. RESULTS: Masseter thickness significantly reduced in all groups at 12 weeks, compared with that in the placebo group. A dose-dependent reduction in masseter thickness was observed at the resting and maximal clenching positions. Sonography and 3-dimensional imaging revealed a gradual reduction in masseter thickness and volume, respectively, during the first 12 weeks. Despite being slightly effective, a dose of 24 units might be insufficient for resolving square face problems. Patients in Group E reported discomfort during jaw movement. CONCLUSION: Prabotulinum toxin A could effectively improve lower face contour without major complications, with an optimal dose of 48 to 72 units, followed by reinjection after 12 weeks.

Comparison of different energy response for lipolysis using a 1,060-nm laser: An animal study of three pigs.

BACKGROUND: Non-invasive body-sculpting procedures are becoming increasingly popular. The application of 1,060 nm of laser energy transcutaneously to hyperthermically induce the disruption of fat cells in the abdomen is a type of non-invasive procedure. AIMS: The purpose of this study was to compare the treatment results from two parameters of the same system, each with different energy output levels, in an in vivo porcine model to determine the most effective application. METHODS: Female pigs (n = 3) were used in this study. We examined the effects of the treatment using photography, ultrasonography, gross and microscopic pathology, and histological examination in order to determine the mechanism of action, efficacy, and safety of the procedure. Blood chemistry analysis was performed before each session to check lipid levels and to monitor for any adverse changes in markers that may indicate liver damage. Biopsies were taken and routinely processed with hematoxylin and eosin and Oil Red O stains to examine for tissue damage at baseline and after each treatment. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) assays were performed to check for apoptotic-related DNA damage. RESULTS: Ultrasonic imaging of the same area before and after the application of 1,060 nm of laser energy at outputs of 0.9 and 1.4 W/cm2 showed that the density of the fat layer changed immediately after irradiation due to the transient heat transfer in the fat layer. Preclinical evaluation was performed to obtain comparison data on the safety and efficacy of subcutaneous fat reduction after applying the different energy outputs of 0.9 and 1.4 W/cm2 . CONCLUSION: Based on our findings, we suggest that long-term histologic changes through the use of these devices suggest a comparative effectiveness of the treatment energy.

Preclinical evaluation for removal of bulging lower eyelid fat using ultrasound-assisted lipolysis on a Yorkshire pig.

PURPOSE: The purpose of this study is to evaluate the efficacy and safety of treating lower eyelid fat bulging with ultrasound-assisted lipolysis (UAL) by performing a preclinical evaluation of the procedure on a Yorkshire pig. METHODS: Two white Yorkshire pigs had lower eyelid fat bulging treated with UAL using a probe with a diameter of 1.0 mm or less. Fourteen days after treatment, we evaluated the changes in fat thickness from ultrasound, changes in skin contour (volume and height) from the Antera 3D™, and the disruption of fat cells and changes in collagen synthesis from histological evaluation. RESULTS: Fourteen days after treatment, the fat layer was significantly reduced with no damage to the skin surface. The mean change in the subcutaneous fat layer thickness was decreased 1.51-0.75 mm in ultrasound analysis. The skin contour of the treated area also decreased with time from 202.5 to 163.5 mm in mean volume and 0.8111 to 0.646 mm in mean height. Masson's trichrome staining showed that the UAL treatment induced the regeneration and remodeling of collagen. CONCLUSION: The results of this study demonstrate that UAL successfully reduced the bulging lower eyelid fat of a Yorkshire pig and also increased collagen contraction to tighten skin. UAL may be a beneficial and well-tolerated treatment option for lower eyelid fat bulging.

310 nm UV-LEDs attenuate imiquimod-induced psoriasis-like skin lesions in C57BL/6 mice and inhibit IL-22-induced STAT3 expression in HaCaT cells.

Ultraviolet light-emitting diodes (UV-LEDs) are a novel light source for phototherapy. This study aimed to evaluate the therapeutic effects of UV-LEDs on psoriasis. Importantly, 310 nm UV-LEDs have not been studied in psoriasis in vitro and in vivo. Effects due to 310 nm UV-LED and 311 nm narrowband ultraviolet B (NBUVB) irradiation were compared for suppressing IL-22-induced activation of STAT3 expression using cell viability assay, western blotting, and immunocytochemistry. C57BL/6 mice were topically treated with imiquimod (IMQ) for 6 consecutive days and degenerative changes were observed. Test groups were irradiated with a 310 nm UV-LED and 311 nm NBUVB. Phenotypic observations, histopathological examinations, and ELISA were conducted with skin and blood samples. STAT3-dependent IL-22 signalling and effects in keratinocytes are negatively regulated by the 310 nm UV-LED, which significantly ameliorated IMQ-induced psoriasis-like dermatitis development and reduced Th17 cytokine levels (IL-17A, IL-22) in serum and dorsal skin. Histopathological findings showed decreases in epidermal thickness and inflammatory T-cell infiltration in the UV-LED-irradiated groups. Quantitative PCR confirmed a UV radiation energy-dependent decrease in IL-17A and IL-22 mRNA levels. The results demonstrated that UV-LEDs had anti-inflammatory and immunoregulatory effects. So, UV-LED phototherapy inhibits psoriasis development by suppressing STAT3 protein and inflammatory cytokines and could be useful in treating psoriasis.

The Effects of Fabric Containing Chamaecyparis obtusa Essential Oil on Atopic Dermatitis-Like Lesions: A Functional Clothing Possibility.

BACKGROUND: Essential oil derived from Chamaecyparis obtusa (EOCO) has been used as an alternative treatment for allergy-related diseases due to its immune-modulating characteristics. Clothing has the longest and most intense contact with human skin, and functional fabrics with intrinsic properties have been increasingly implemented in medical applications. Specially designed fabrics may support atopic dermatitis (AD) treatment. In this study, the effects of fabric containing EOCO on AD were investigated using an NC/Nga mouse model. METHODS: The fabric was applied for 6 h per day for 14 days. The therapeutic effects were evaluated according to measurements of skin lesion severity (modified SCORAD score), transepidermal water loss (TEWL), serum IgE and inflammatory cytokine levels, lesion thickness measured after hematoxylin and eosin staining, and immunohistochemical and Western blot analysis for skin epidermal differentiation protein. RESULTS: The EOCO group exhibited significantly reduced modified SCORAD score, TEWL, and serum IgE levels. Among the inflammatory cytokines analyzed, only the mean values of regulated on activation, normal T cell expressed and secreted were observed to be decreased compared with other control groups. The histological analysis of the skin also revealed that the EOCO group expressed reduced epidermal hyperplasia and recovered filaggrin, involucrin, and loricrin expression. CONCLUSIONS: It was confirmed that fabric containing EOCO has anti-atopic and anti-inflammatory properties. The study data show that fabric containing EOCO can be implemented as an alternative functional clothing for people suffering from AD.

Improvement of a slimming cream's efficacy using a novel fabric as a transdermal drug delivery system: An in vivo and in vitro study.

Penetration of any compound into the body from the outside is prevented primarily by the corneal layer of the epidermis. The only way to circumvent the properties of the corneal layer is to disrupt it. Currently, transdermal systems can currently only deliver drugs that are of low molecular weight. The purpose of the present study was to assess the improvement of the slimming cream's efficacy using a novel fabric, with the aim of developing an improved method for transdermal drug delivery. The current study was conducted on four groups of guinea pigs. The control group was untreated, whereas the test groups were treated with either slimming cream and no fabric, slimming cream with 100% cotton fabric or slimming cream with the novel fabric. Ultrasound and microscopic histological analysis were used to assess animals. The results demonstrated that compared with the other groups, the novel fabric group demonstrated the greatest reductions in fat layer thickness, adipocyte size and number and proliferator-activated receptor-γ levels in adipose tissue. Furthermore, the novel fabric also enhanced the transdermal delivery of rhodamine B base and caffeine penetration compared with the control fabric (3.18-fold). In conclusion, the results of the present study demonstrated that the novel fabric can potentially be used to enhance transdermal drug delivery.

Comparative Evaluation of the Effectiveness of Novel Hyaluronic Acid-Polynucleotide Complex Dermal Filler.

HA (Hyaluronic acid) filler, the most commonly used dermal filler, causes several side effects. HA-PN (Hyaluronic acid-Polynucleotide), a new composite filler, has excellent biocompatibility and induces tissue regeneration. In this study, we compare the efficacies and safety profiles of these fillers. The characteristics of HA and HA-PN fillers were compared using scanning electron microscopy and rheometry. No morphological difference was noted between the fillers. However, the latter had higher viscosity and elasticity values. The HA-PN filler induced higher cell migration than the HA filler in a wound healing assay. It was also found to stimulate better collagen synthesis in human and mouse fibroblasts. The HA and HA-PN fillers were injected into SKH1 hairless mice to determine changes in their volume for up to 24 weeks. Increased cell migration and collagen synthesis were observed in mice injected with the HA-PN complex filler. Although the safety and durability of the HA and HA-PN fillers were similar, the latter induced a lower transient receptor potential vanilloid 4 expression and caused less stimulation upon injection. In conclusion, HA-PN complex fillers can stimulate fibroblast growth and facilitate volume growth and skin regeneration.

Inhibition of melanogenesis by sodium 2-mercaptoethanesulfonate.

Sodium 2-mercaptoethanesulfonate (mesna) is a protective agent that is widely used in medicine because of its antioxidant effects. Recently, reactive oxygen species (ROS) were shown to increase pigmentation. Thus, ROS scavengers and inhibitors of ROS production may suppress melanogenesis. Forkhead box-O3a (FoxO3a) is an antimelanogenic factor that mediates ROS-induced skin pigmentation. In this study, we aimed to investigate the whitening effect of mesna and the signaling mechanism mediating this effect. Human melanoma (MNT-1) cells were used in this study. mRNA and protein expression were measured by real-time quantitative PCR and Western blotting analysis to track changes in FoxO3a-related signals induced by mesna. An immunofluorescence assay was performed to determine the nuclear translocation of FoxO3a. When MNT-1 melanoma cells were treated with mesna, melanin production and secretion decreased. These effects were accompanied by increases in FoxO3a activation and nuclear translocation, resulting in downregulation of four master genes of melanogenesis: MITF, TYR, TRP1, and TRP2. We found that mesna, an antioxidant and radical scavenger, suppresses melanin production and may therefore be a useful agent for the clinical treatment of hyperpigmentation disorders.

Protective effects of human umbilical cord blood­derived mesenchymal stem cells against dexamethasone­induced apoptotic cell death in hair follicles.

Alopecia is a common and distressing condition, and developing new therapeutic agents to prevent hair loss is important. Human umbilical cord blood­derived mesenchymal stem cells (hUCB­MSCs) have been studied intensively in regenerative medicine. However, the therapeutic potential of these cells against hair loss and hair organ damage remains unclear, and the effects of hUCB­MSC transplantation on hair loss require evaluation. The current study aimed to investigate the effects of hUCB­MSCs on hair regression in vivo and restoration of anagen conduction on hair growth in vitro. The effects of hUCB­MSCs were explored in mouse catagen induction models using a topical treatment of 0.1% dexamethasone to induce hair regression. Dexamethasone was also used to simulate a stress environment in vitro. The results demonstrated that hUCB­MSCs significantly prevented hair regression induced by dexamethasone topical stimulation in vivo. Additionally, hUCB­MSCs significantly increased the proliferation of human dermal papilla cells (hDPCs) and HaCaT cells, which are key constituent cells of the hair follicle. Stimulation of vascular endothelial growth factor secretion and decreased expression of DKK­1 by hUCB­MSCs were also observed in hDPCs. Restoration of cell viability by hUCB­MSCs suggested that these cells exerted a protective effect on glucocorticoid stress­associated hair loss. In addition, anti­apoptotic effects and regulation of the autophagic flux recovery were observed in HaCaT cells. The results of the present study indicated that hUCB­MSCs may have the capacity to protect hair follicular dermal papilla cells and keratinocytes, thus preventing hair loss. Additionally, the protective effects of hUCB­MSCs may be resistant to dysregulation of autophagy under harmful stress.

Prospective, preclinical comparison of the performance between radiofrequency microneedling and microneedling alone in reversing photoaged skin.

BACKGROUND: There is a tremendous demand for dermal rejuvenation with minimal invasiveness and patient downtime. AIMS: In this study, we evaluated the performance of nonfractional monopolar radiofrequency for the improvement of photoaged skin texture and wrinkles. METHODS: In total, 32 6-week-old female hairless mice were randomized into four groups of eight mice each: (a) healthy control, (b) UVB-exposed, (c) UVB + microneedling, and (d) UVB + microneedle RF. After applying each treatment modality, skin surface was globally investigated and histologically evaluated senile skin change. Immunohistochemistry was tested with the primary antibody to collagen type I and III. RESULTS: After UVB exposure, the Ra value was significantly increased, leading to clinical development of wrinkles with xerotic scales. Depth and number of wrinkles showed gradual improvement in RF-treated mice. The mean Ra value of the RF-treated group decreased significantly. The RF-treated group showed decreased epidermal thickness, suppression of dermal inflammatory cell infiltration, and increased density of collagen fibers and amount of elastic fibers. CONCLUSIONS: Microneedle RF treatment alleviates photoaged skin texture and wrinkles in this mouse model. To the best of our knowledge, our results provide the first evidence that a nonfractional monopolar microneedle radiofrequency device may contribute to the treatment of UV-damaged skin.

Boehmite enhances hair follicle growth via stimulation of dermal papilla cells by upregulating ß-catenin signalling.

Hair growth, a complex process, has long been the subject of intense research. Recent developments in material technology have revealed boehmite as a new therapeutic modality for use in wound healing and scar reduction, indicating its beneficial effects. Nonetheless, the biological bases of the beneficial effects of boehmite remain unknown. We investigated the hair growth properties of boehmite in vitro and in vivo and observed dose-dependent proliferation of human dermal papilla cells (hDPCs) in vitro and hair regrowth in a mouse model. To investigate the effects of boehmite on the promotion of cell transition to the anagen phase, we evaluated hDPC viability, alkaline phosphatase (ALP) activity, protein expression and vascular endothelial growth factor (VEGF) secretion in vitro and assessed the anagen-promoting effects of boehmite via gross observation and histological analysis in a mouse model. Boehmite increased hDPC viability, ALP activity, AKT/GSK3ß/ß-catenin pathway activity, anagen-related gene expression and VEGF secretion; moreover, it accelerated hair regrowth in a catagen-anagen transition model via upregulation of ß-catenin signalling and follicular cell proliferation. Collectively, our results indicate that boehmite accelerates hair growth, partly via its effects on critical events in the active phase of the hair follicle cycle, including the promotion of the proliferation of hDPCs and their immediate progeny to the follicle base.

Efficacy and Safety of High-Intensity Focused Ultrasound for Noninvasive Abdominal Subcutaneous Fat Reduction.

BACKGROUND: Demand for noninvasive body contouring has increased. OBJECTIVE: We evaluated the efficacy and safety of a thermal high-intensity focused ultrasound (HIFU) device for abdominal body shaping. PATIENTS AND METHODS: Adults with a body mass index ≤30 kg/m and an abdominal subcutaneous fat tissue thickness ≥2.5 cm were enrolled for HIFU treatment at energy levels of 150 J/cm (first session) and 135 J/cm (second session). The primary end point was a change from baseline waist circumference at post-treatment Week 8. Secondary efficacy end points were: changes in body weight, waist/hip ratio, and fat thickness assessed by ultrasound, caliper, and a fat CT scan. The Global Aesthetic Improvement Scale was evaluated by both investigators and subjects. RESULTS: The primary assessment achieved statistical significance, showing a reduction of 3.43 cm in mean waist circumference. The treatment effect was cumulative, with a steady decrease in waist circumference and fat thickness. The mean pain scores immediately after treatment were 4.45 ± 2.74 on a scale of 1 to 10 with 10 being the most painful, which decreased to 1.10 ± 1.33 after 1 week. CONCLUSION: High-intensity focused ultrasound is an effective and safe treatment modality for reducing waist circumference in nonobese individuals with focal fat accumulation.

Anti­photoaging and anti­oxidative activities of natural killer cell conditioned medium following UV­B irradiation of human dermal fibroblasts and a reconstructed skin model.

Conditioned media from various sources comprise numerous growth factors and cytokines and are known to promote the regeneration of damaged tissues. Among these, natural killer cell conditioned medium (NK­CdM) has been shown to stimulate collagen synthesis and the migration of fibroblasts during the wound healing process. With a long­term aim of developing a treatment for skin photoaging, the ability of NK­CdM to prevent ultraviolet­B (UV­B) damage was assessed in neonatal human dermal fibroblasts (NHDFs) and an in vitro reconstructed skin model. The factors present in NK­CdM were profiled using an antibody array analysis. Protein and mRNA levels in UV­B exposed NHDFs treated with NK­CdM were measured by western blotting and quantitative reverse transcription­PCR, respectively. The total antioxidant capacity of NK­CdM was determined to assess its ability to suppress reactive oxygen species. The anti­photoaging effect of NK­CdM was also assessed in a 3D reconstituted human full skin model. NK­CdM induced proliferation of UV­B­treated NHDFs, increased procollagen expression, and decreased matrix metalloproteinase (MMP)­1 expression. NK­CdM also exhibited a potent antioxidant activity as measured by the total antioxidant capacity. NK­CdM inhibited UV­B­induced collagen degradation by inactivating MAPK signaling. NK­CdM also elicited potential anti­wrinkle effects by inhibiting the UV­B­induced increase in MMP­1 expression levels in a 3D reconstituted human full skin model. Taken together, the suppression of both UV­B­induced MMP­1 expression and JNK activation by NK­CdM suggests NK­CdM as a possible candidate anti­skin aging agent.

Role of mechanical and thermal damage in pericapsular inflammatory response to injectable silicone in a rabbit model.

Silicone is used widely for tissue augmentation in humans. However, late complications, such as delayed inflammation and capsular contracture, remain uncharacterized, despite their importance. In the present study, we aimed to determine whether mechanical and thermal damage induce capsular inflammation around a foreign body, and elucidate the biological mechanism underlying this phenomenon. We injected silicone into the subcutaneous layer of the skin of New Zealand white rabbits. The rabbits were divided into two groups: the control group received no treatment; in the experimental group, external force was applied near the injection silicone using high-intensity focused ultrasound (HIFU). Tissues near the injected silicone were harvested from both groups on Days 4, 7, and 30 after HIFU treatment for comparative analysis. Visual and histological examinations showed clearly increased inflammation in the experimental group compared with that in the control group. Furthermore, capsular tissue from the experimental group displayed markedly increased collagen production. Immunofluorescence revealed marked activation of macrophages in the early stages of inflammation (Days 4 and 7 after HIFU treatment), which decreased on Day 30. Assessment of cytokine activation showed significantly increased expression of heat shock protein (HSP)27, HSP60, HSP70, toll-like receptor (TLR)2, TLR4, and interleukin-8 in the experimental group. The expression of transforming growth factor-ß1 did not increase significantly in the experimental group. In conclusion, damage to tissues around the injected silicone induced capsular inflammation. Macrophages and damage-associated molecular pattern molecules were involved in the early stages of inflammation. HSP release activated TLRs, which subsequently activated innate immunity and induced the inflammatory response.

Biostimulatory effects of polydioxanone, poly-d, l lactic acid, and polycaprolactone fillers in mouse model.

BACKGROUND: Numerous fillers are increasingly used for augmentation of volume loss and relaxation of facial wrinkles. Collagen stimulators are the latest next-generation dermal fillers that can induce neocollagenesis. To investigate biophysical characteristics, safety, and efficacy of newly developed polydioxanone (PDO) filler in comparison with poly-l lactic acid (PLLA) and polycaprolactone (PCL) fillers. METHODS: In vitro assay, morphology of particles, and rheological property of fillers were measured. A total of 24 female hairless mice (SKH1-Hrhr ) were randomly divided into three groups and injected with PDO, PLLA, or PCL fillers. Durability of fillers was assessed at 0, 3 days, and 1, 4, 8, 12 weeks after injection using folliscope and PRIMOS. To determine biocompatibility and neocollagenesis, histologic evaluation was performed at 1, 4, 8, and 12 weeks after injection. Efficacy was also evaluated based on skin surface roughness changes using PRIMOS in a hairless mouse photoaging model. RESULTS: In the particle morphology test, PDO microspheres had an irregular surface and were spherical and uniformly sized. PDO filler demonstrated similar neocollagenesis and inflammatory response to other collagen stimulators. PDO filler showed better biodegradability than PLLA and PCL fillers. In the hairless mouse photoaging model, there was a statistically significant decrease in skin surface roughness after PDO filler injection. CONCLUSIONS: Our data suggest that newly developed collagen stimulating PDO filler might be a safe and effective option for correction of volume loss and rejuvenation of photoaging skin.

Comparative Evaluation of the Biodegradability and Wrinkle Reduction Efficacy of Human-Derived Collagen Filler and Hyaluronic Acid Filler.

BACKGROUND: The development of fillers for wrinkle prevention is growing to meet rising demands to reduce the aging of skin. OBJECTIVE: In this experiment, we confirmed the effects of human collagen and hyaluronic acid filler biodegradation for wrinkle reduction using a photo-aging mouse model. MATERIALS AND METHODS: A total of 10 hairless mice (SKH1-Hrhr) were randomly divided into two groups and injected with hyaluronic acid and human-derived collagen filler. At 0, 2, 4, 8, and 12 weeks, PRIMOSlite®, folliscope, and MRI were used to evaluate the biodegradability of the fillers after the injections. We also studied the photo-aging mouse model for skin roughness and histological evaluation and confirmed that the filler injection had excellent anti-wrinkle effects. RESULTS: Human-derived collagen fillers had excellent biodegradability compared to that of hyaluronic acid fillers. The skin surface roughness in the photo-aging mouse models was significantly reduced after injections of human-derived collagen filler. CONCLUSION: Our results showed that the human-derived collagen filler had excellent biodegradability and effectively reduced wrinkle formation in a photo-aging mouse model. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Effects of Intradermal Radiofrequency Treatment and Intense Pulsed Light Therapy in an Acne-induced Rabbit Ear Model.

Acne vulgaris is a common condition that can have psychologically deleterious effects. Since current treatments carry the risks of antibiotic resistance or teratogenicity, novel treatment modalities are under investigation. Our study investigated the efficacy of intradermal radiofrequency treatment (RF) and intense pulsed light (IPL) in the treatment of acne vulgaris in a rabbit ear model. We evaluated the effectiveness of IPL, RF, and a combination treatment on cultured Cuticobacterium acnes strains in an induced rabbit ear model, according to clinical outcomes as well as histological and immunological approaches. We found that RF treatment markedly decreases papule volume, while IPL appears to have an immunomodulatory effect. In combination, the two have an additive effect in treatment. These findings suggest that combination of RF and IPL may be an effective therapeutic option for the treatment of acne vulgaris.