Efficacy of combined treatment with human adipose tissue stem cell-derived exosome-containing solution and microneedling for facial skin aging: A 12-week prospective, randomized, split-face study.

BACKGROUND: Studies have reported promising results of mesenchymal stem cell therapies for skin aging. However, in the use of mesenchymal stem cells, some drawbacks including rarely possible tumorigenicity and low engraftment rates have limited their widespread clinical use. Adipose tissue stem cell-derived exosomes (ASCEs) are emerging as effective cell-free therapeutic agents. AIMS: It was evaluated the clinical efficacy of combining the application of human ASCE-containing solution (HACS) with microneedling to treat facial skin aging. METHODS: A 12-week, prospective, randomized, split-face, comparative study was conducted. Twenty-eight individuals underwent three treatment sessions separated by 3-week intervals and were followed up for 6 weeks after the last session. At each treatment session, HACS and microneedling were administered to one side of the face, and normal saline solution and microneedling were administered to the other side as a control. RESULTS: The Global Aesthetic Improvement Scale score was significantly higher on the HACS-treated side than on the control side at the final follow-up visit (p = 0.005). Objective measurements obtained by different devices including PRIMOS Premium, Cutometer MPA 580, Corneometer CM 825, and Mark-Vu confirmed greater clinical improvements in skin wrinkles, elasticity, hydration, and pigmentation on the HACS-treated side than on the control side. The results of the histopathological evaluation were consistent with the clinical findings. No serious adverse events were observed. CONCLUSIONS: These findings demonstrate that combined treatment using HACS and microneedling is effective and safe for treating facial skin aging.

The degradation of performance of a state-of-the-art skin image classifier when applied to patient-driven internet search.

Model Dermatology ( https://modelderm.com ; Build2021) is a publicly testable neural network that can classify 184 skin disorders. We aimed to investigate whether our algorithm can classify clinical images of an Internet community along with tertiary care center datasets. Consecutive images from an Internet skin cancer community ('RD' dataset, 1,282 images posted between 25 January 2020 to 30 July 2021; https://reddit.com/r/melanoma ) were analyzed retrospectively, along with hospital datasets (Edinburgh dataset, 1,300 images; SNU dataset, 2,101 images; TeleDerm dataset, 340 consecutive images). The algorithm's performance was equivalent to that of dermatologists in the curated clinical datasets (Edinburgh and SNU datasets). However, its performance deteriorated in the RD and TeleDerm datasets because of insufficient image quality and the presence of out-of-distribution disorders, respectively. For the RD dataset, the algorithm's Top-1/3 accuracy (39.2%/67.2%) and AUC (0.800) were equivalent to that of general physicians (36.8%/52.9%). It was more accurate than that of the laypersons using random Internet searches (19.2%/24.4%). The Top-1/3 accuracy was affected by inadequate image quality (adequate = 43.2%/71.3% versus inadequate = 32.9%/60.8%), whereas participant performance did not deteriorate (adequate = 35.8%/52.7% vs. inadequate = 38.4%/53.3%). In this report, the algorithm performance was significantly affected by the change of the intended settings, which implies that AI algorithms at dermatologist-level, in-distribution setting, may not be able to show the same level of performance in with out-of-distribution settings.

Exosomes derived from human adipose tissue-derived mesenchymal stem cells for the treatment of dupilumab-related facial redness in patients with atopic dermatitis: A report of two cases.

BACKGROUND: Atopic dermatitis is a chronic, pruritic, and inflammatory dermatosis that affects approximately 20% of children and 10% of adults worldwide. Dupilumab facial redness is gaining attention as additional cases are coming to light in the medical literature. OBJECTIVES AND METHODS: Exosomes are nano-sized vesicles that are constantly released by almost all cells. They can travel between cells and transport their cargo (lipids, proteins, and nucleic acids), making them a possible cell-free therapeutic option for various diseases. Herein, we investigated whether topical application of human adipose tissue-derived mesenchymal stem cell-derived exosomes could reduce dupilumab facial redness in patients with severe atopic dermatitis. RESULTS: Two patients with atopic dermatitis and refractory dupilumab facial redness were successfully treated with electroporation-assisted topical application of human adipose tissue-derived mesenchymal stem cell-derived exosomes. Six repeated sessions of treatment, with an interval of 1 week between each session, led to marked improvement in erythematous facial lesions. CONCLUSIONS: We suggest that human adipose tissue-derived mesenchymal stem cell-derived exosomes may serve as an effective agent in the management of dupilumab facial redness. However, further controlled studies with a larger number of patients are necessary to confirm the efficacy and safety of this agent, as well as the optimal treatment protocol.

Tightening and Reduction of Unwanted Submental Fat Using Triple-Layer High-Intensity Focused Ultrasound: Clinical and 3-Dimensional Imaging Analysis.

BACKGROUND: Unwanted submental fat (SMF) is aesthetically unappealing, but methods of reduction are either invasive or lack evidence of their use. OBJECTIVE: The authors sought to evaluate the safety and efficacy of a novel triple-layer high-intensity focused ultrasound (HIFU) regimen for SMF reduction. METHODS: Forty Korean subjects with moderate/severe SMF were evaluated after receiving a session of triple-layer HIFU treatments (using 3.0-, 4.5-, and 6.0-mm focusing transducers). The objective evaluation based on the 5-point Clinician-Reported Submental Fat Rating Scale (CR-SMFRS) and patients' satisfaction based on the 7-point Subject Self-Rating Scale (SSRS) were determined 8 weeks after treatment. Three-dimensional image analysis was also performed. RESULTS: At the follow-up visit, the proportion of treatment responders defined as subjects with ≥1-point improvement in CR-SMFRS was 62.5%, and the proportion of patients satisfied with appearance of their face and chin (score ≥4 on the SSRS) was 67.5% of the total patients. The results of 3-dimensional analysis were consistent with clinical observations. Only mild and transient side effects were observed for some patients with no serious adverse effects. CONCLUSION: The triple-layer HIFU regimen including the novel 6.0-mm transducer has benefits for tightening and rejuvenation of the area with unwanted SMF, showing reasonable safety profiles.

Assessment of deep neural networks for the diagnosis of benign and malignant skin neoplasms in comparison with dermatologists: A retrospective validation study.

BACKGROUND: The diagnostic performance of convolutional neural networks (CNNs) for diagnosing several types of skin neoplasms has been demonstrated as comparable with that of dermatologists using clinical photography. However, the generalizability should be demonstrated using a large-scale external dataset that includes most types of skin neoplasms. In this study, the performance of a neural network algorithm was compared with that of dermatologists in both real-world practice and experimental settings. METHODS AND FINDINGS: To demonstrate generalizability, the skin cancer detection algorithm (https://rcnn.modelderm.com) developed in our previous study was used without modification. We conducted a retrospective study with all single lesion biopsied cases (43 disorders; 40,331 clinical images from 10,426 cases: 1,222 malignant cases and 9,204 benign cases); mean age (standard deviation [SD], 52.1 [18.3]; 4,701 men [45.1%]) were obtained from the Department of Dermatology, Severance Hospital in Seoul, Korea between January 1, 2008 and March 31, 2019. Using the external validation dataset, the predictions of the algorithm were compared with the clinical diagnoses of 65 attending physicians who had recorded the clinical diagnoses with thorough examinations in real-world practice. In addition, the results obtained by the algorithm for the data of randomly selected batches of 30 patients were compared with those obtained by 44 dermatologists in experimental settings; the dermatologists were only provided with multiple images of each lesion, without clinical information. With regard to the determination of malignancy, the area under the curve (AUC) achieved by the algorithm was 0.863 (95% confidence interval [CI] 0.852-0.875), when unprocessed clinical photographs were used. The sensitivity and specificity of the algorithm at the predefined high-specificity threshold were 62.7% (95% CI 59.9-65.1) and 90.0% (95% CI 89.4-90.6), respectively. Furthermore, the sensitivity and specificity of the first clinical impression of 65 attending physicians were 70.2% and 95.6%, respectively, which were superior to those of the algorithm (McNemar test; p < 0.0001). The positive and negative predictive values of the algorithm were 45.4% (CI 43.7-47.3) and 94.8% (CI 94.4-95.2), respectively, whereas those of the first clinical impression were 68.1% and 96.0%, respectively. In the reader test conducted using images corresponding to batches of 30 patients, the sensitivity and specificity of the algorithm at the predefined threshold were 66.9% (95% CI 57.7-76.0) and 87.4% (95% CI 82.5-92.2), respectively. Furthermore, the sensitivity and specificity derived from the first impression of 44 of the participants were 65.8% (95% CI 55.7-75.9) and 85.7% (95% CI 82.4-88.9), respectively, which are values comparable with those of the algorithm (Wilcoxon signed-rank test; p = 0.607 and 0.097). Limitations of this study include the exclusive use of high-quality clinical photographs taken in hospitals and the lack of ethnic diversity in the study population. CONCLUSIONS: Our algorithm could diagnose skin tumors with nearly the same accuracy as a dermatologist when the diagnosis was performed solely with photographs. However, as a result of limited data relevancy, the performance was inferior to that of actual medical examination. To achieve more accurate predictive diagnoses, clinical information should be integrated with imaging information.

Twenty-eight-year incidence and characteristics of post-transplant skin cancers: Comparative analysis of past and recent 10-year experience.

Because primary skin cancers in organ transplant recipients are rare, little is known about the characteristics and risk factors for skin cancers in organ transplant recipients. We searched the Asan Medical Center database of 13 469 organ transplant recipients for cases of all skin cancers from January 1990 to December 2018. Characteristics of and risk factors for skin cancers were analyzed and compared according to the period of transplantation. Of the identified 113 patients with skin cancers, squamous cell carcinoma was the most common cancer followed by basal cell carcinoma and Kaposi sarcoma. The cumulative incidence of skin cancers at 28 years was 5.3%. Over the 10-year period from January 2009 to December 2018, the standardized incidence ratio for premalignant in situ skin lesions increased, whereas the standardized incidence ratio for skin cancers decreased. Age at transplantation and treatment with more than two immunosuppressive agents were risk factors for the development of new skin cancers in organ transplant recipients. Over the most recent 10-year period, post-transplant skin cancers have been found earlier and diversified compared with in the previous period.

Mesenchymal Stem/Stromal Cell-Derived Exosomes for Immunomodulatory Therapeutics and Skin Regeneration.

Exosomes are nano-sized vesicles that serve as mediators for cell-to-cell communication. With their unique nucleic acids, proteins, and lipids cargo compositions that reflect the characteristics of producer cells, exosomes can be utilized as cell-free therapeutics. Among exosomes derived from various cellular origins, mesenchymal stem cell-derived exosomes (MSC-exosomes) have gained great attention due to their immunomodulatory and regenerative functions. Indeed, many studies have shown anti-inflammatory, anti-aging and wound healing effects of MSC-exosomes in various in vitro and in vivo models. In addition, recent advances in the field of exosome biology have enabled development of specific guidelines and quality control methods, which will ultimately lead to clinical application of exosomes. This review highlights recent studies that investigate therapeutic potential of MSC-exosomes and relevant mode of actions for skin diseases, as well as quality control measures required for development of exosome-derived therapeutics.

Toxicological evaluation of exosomes derived from human adipose tissue-derived mesenchymal stem/stromal cells.

Several studies report that the therapeutic mechanism of action of mesenchymal stem/stromal cells (MSCs) is mainly mediated by paracrine factors that are released from MSCs such as exosomes. Exosomes are nano-sized extracellular vesicles that are transferred to target cells for cell-to-cell communication. Although MSC-derived exosomes (MSC-exosomes) are suggested as novel cell-free therapeutics for various human diseases, evaluation studies for the safety and toxicity of MSC-exosomes are limited. The purpose of our study was to evaluate the toxicological profile, including skin sensitization, photosensitization, eye and skin irritation, and acute oral toxicity using exosomes derived from human adipose tissue-derived MSCs (ASC-exosomes) in accordance with the OECD guidelines and the principles of Good Laboratory Practice. The ASC-exosomes were classified as a potential non-sensitizer in the skin sensitization test, UN GHS no category in the eye irritation test, and as a skin non-irritant in the skin irritation test, and did not induce any toxicity in the phototoxicity test or in acute oral toxicity testing. Our findings are the first to suggest that ASC-exosomes are safe for use as a topical treatment, with no adverse effects in toxicological testing, and have potential application as a therapeutic agent, cosmetic ingredient, or for other biological uses.

Augmented Intelligence Dermatology: Deep Neural Networks Empower Medical Professionals in Diagnosing Skin Cancer and Predicting Treatment Options for 134 Skin Disorders.

Although deep learning algorithms have demonstrated expert-level performance, previous efforts were mostly binary classifications of limited disorders. We trained an algorithm with 220,680 images of 174 disorders and validated it using Edinburgh (1,300 images; 10 disorders) and SNU datasets (2,201 images; 134 disorders). The algorithm could accurately predict malignancy, suggest primary treatment options, render multi-class classification among 134 disorders, and improve the performance of medical professionals. The area under the curves for malignancy detection were 0.928 ± 0.002 (Edinburgh) and 0.937 ± 0.004 (SNU). The area under the curves of primary treatment suggestion (SNU) were 0.828 ± 0.012, 0.885 ± 0.006, 0.885 ± 0.006, and 0.918 ± 0.006 for steroids, antibiotics, antivirals, and antifungals, respectively. For multi-class classification, the mean top-1 and top-5 accuracies were 56.7 ± 1.6% and 92.0 ± 1.1% (Edinburgh) and 44.8 ± 1.2% and 78.1 ± 0.3% (SNU), respectively. With the assistance of our algorithm, the sensitivity and specificity of 47 clinicians (21 dermatologists and 26 dermatology residents) for malignancy prediction (SNU; 240 images) were improved by 12.1% (P < 0.0001) and 1.1% (P < 0.0001), respectively. The malignancy prediction sensitivity of 23 non-medical professionals was significantly increased by 83.8% (P < 0.0001). The top-1 and top-3 accuracies of four doctors in the multi-class classification of 134 diseases (SNU; 2,201 images) were increased by 7.0% (P = 0.045) and 10.1% (P = 0.0020), respectively. The results suggest that our algorithm may serve as augmented intelligence that can empower medical professionals in diagnostic dermatology.

Exosomes from Human Adipose Tissue-Derived Mesenchymal Stem Cells Promote Epidermal Barrier Repair by Inducing de Novo Synthesis of Ceramides in Atopic Dermatitis.

Atopic dermatitis (AD) is a multifactorial, heterogeneous disease associated with epidermal barrier disruption and intense systemic inflammation. Previously, we showed that exosomes derived from human adipose tissue-derived mesenchymal stem cells (ASC-exosomes) attenuate AD-like symptoms by reducing multiple inflammatory cytokine levels. Here, we investigated ASC-exosomes' effects on skin barrier restoration by analyzing protein and lipid contents. We found that subcutaneous injection of ASC-exosomes in an oxazolone-induced dermatitis model remarkably reduced trans-epidermal water loss, while enhancing stratum corneum (SC) hydration and markedly decreasing the levels of inflammatory cytokines such as IL-4, IL-5, IL-13, TNF-α, IFN-γ, IL-17, and TSLP, all in a dose-dependent manner. Interestingly, ASC-exosomes induced the production of ceramides and dihydroceramides. Electron microscopic analysis revealed enhanced epidermal lamellar bodies and formation of lamellar layer at the interface of the SC and stratum granulosum with ASC-exosomes treatment. Deep RNA sequencing analysis of skin lesions demonstrated that ASC-exosomes restores the expression of genes involved in skin barrier, lipid metabolism, cell cycle, and inflammatory response in the diseased area. Collectively, our results suggest that ASC-exosomes effectively restore epidermal barrier functions in AD by facilitating the de novo synthesis of ceramides, resulting in a promising cell-free therapeutic option for treating AD.

Combined treatment of recalcitrant papulopustular rosacea involving pulsed dye laser and fractional microneedling radiofrequency with low-dose isotretinoin.

BACKGROUND: While a considerable number of cases with papulopustular rosacea (PPR) are resistant to conventional medications, therapeutic regimens are not currently established. Pulsed dye laser (PDL) and fractional microneedling radiofrequency (FMR) have previously demonstrated satisfactory results for anti-angiogenesis, anti-inflammation, and dermal remodeling. AIMS: To evaluate the efficacy and safety of novel combination regimen with low-dose oral isotretinoin, PDL, and FMR in the treatment of recalcitrant PPR. PATIENTS AND METHODS: A retrospective study was undertaken for recalcitrant PPR patients to evaluate the clinical course of novel combination regimen. Twenty-five PPR patients who had failed in previous first-line therapies were enrolled. They were treated with three sessions of PDL and FMR consecutively at 4-week intervals, maintaining daily oral administration of 10 mg isotretinoin for 8 weeks. Objective assessments, erythema index measurement, and patients' subjective satisfaction were evaluated at each visit and 16 weeks after the final treatment. RESULTS: At the final follow-up visit, the number of papules and pustules decreased by 71%, and erythema index by 54% compared with baseline (P < 0.05 for both). Physician's global assessment based on rosacea severity score and patients' subjective assessments paralleled with these results. No serious side effect was observed during whole study periods. CONCLUSION: This novel combination regimen demonstrated satisfactory efficacy with reasonable safety profiles for the treatment of recalcitrant PPR.

A Novel Combined Light-Based Treatment of Acne Vulgaris With 1,450-nm Diode Laser and 450-nm Blue Light.

BACKGROUND: Nonablative 1,450-nm diode laser (DL) and visible blue light (BL) have been effectively used for acne with superior safety profiles. OBJECTIVE: To evaluate synergistic effects of sequential DL and BL application for acne. METHODS: A 20-week, randomized split-face study was conducted to compare clinical courses between 2 facial sides either receiving sequential application of DL and BL or BL alone in 24 patients with mild to moderate facial acne vulgaris. Patients were scheduled to receive 3 consecutive sessions at 4-week intervals. Objective assessments, including revised Leeds grades, lesion counts, and sebum output measurements, and patients' subjective satisfaction were investigated. RESULTS: Both combination and BL sides demonstrated steady improvement of inflammatory acne lesions with 62.3% and 35.2% decreases at the 12-week follow-up visit compared with baseline respectively. For noninflammatory lesions and seborrhea, only combination regimen demonstrated improvement. Patients' subjective assessments paralleled objective findings. For safety profiles, no severe adverse effect was observed on both sides, and mild symptoms resolved spontaneously within a day. CONCLUSION: The combination regimen demonstrated synergistic efficacies for acne and seborrhea, with satisfactory safety profiles. Therefore, a few sessions of these light-based applications would be a viable option for acne treatments.

Clinical Evaluations of a Novel Thread Lifting Regimen Using Barbed Polyglyconate Suture for Facial Rejuvenation: Analysis Using a 3-Dimensional Imaging System.

BACKGROUND: Thread lifting with absorbable sutures has recently gained prominence for rejuvenating ptotic and sagging soft tissues in aging face. A barbed, delayed absorbable polyglyconate monofilament shows significantly high tensile loads with superior flexibility and elasticity. OBJECTIVE: To evaluate the safety and efficacy of novel thread lifting regimen with barbed polyglyconate suture for counteracting the descent and laxity of the aging face. METHODS: A retrospective chart review was conducted for 25 Korean patients with mild to moderate facial skin laxity receiving thread lifting procedures using barbed polyglyconate suture. Dermatologists' objective assessments using a 5-point Global Aesthetic Improvement Scale (GAIS), 3D imaging system, and subjective satisfaction were recorded at baseline and 4 months after treatments. RESULTS: In most patients (84%), GAIS scores were more than score 3 ("improved"), with 40% of score 4 ("much improved") and 24% of score 5 ("excellent") at the follow-up point. Subjective assessments paralleled these patterns. Three-dimensional analysis quantitatively showed volume migration of low face upward, clinically interpreted as facial lifting. No serious adverse effect was observed. CONCLUSION: This novel thread lifting procedure using barbed polyglyconate suture is a safe and effective method for tightening and lifting for aging face with mild to moderate face sagging.

Comparison of novel dual mode vs conventional single pass of a 1450-nm diode laser in the treatment of acne vulgaris for Korean patients: A 20-week prospective, randomized, split-face study.

BACKGROUND: Although a 1450-nm diode laser has been shown to be effective for acne, the conventional high-energy stamp-only regimen is often associated with pain and hyperpigmentation, especially for dark-skinned individuals. AIMS: To evaluate whether the novel dual regimen has clinical advantages for acne treatments compared with conventional regimen in Asian patients. PATIENTS AND METHODS: Twenty-four Korean patients with facial acne were treated with a 1450-nm diode laser through a 20-week, randomized, split-face study. The patients were treated with three consecutive sessions at 4-week intervals. One half of the face received a dual regimen consisting of low-fluence stamping mode (5-6 J/cm2 ) for inflammatory acne lesions only, followed by 4-5 passes of moving mode for the full face. The other side received a single-pass treatment of conventional high-fluence stamp mode (14-15 J/cm2 ). Evaluations for acne, sebum secretion measurements, and safety profiles were performed. RESULTS: At the final 12-week follow-up evaluations, the dual-mode side demonstrated better improvements in both inflammatory and noninflammatory lesion counts, acne severity assessments, and reduction in sebum secretion compared with stamp-only side. Subjective satisfaction for the improvement for acne, seborrhea, and texture correlated well with objective assessments. In addition, degrees of pain and treatment-related side effects were remarkably decreased in the novel dual mode. CONCLUSION: This novel dual regimen of the 1450-nm laser demonstrated improved efficacies for acne and seborrhea with satisfactory safety profiles. Therefore, this regimen would be a viable option for acne treatments either as monotherapy or as combination therapy.

Classification of the Clinical Images for Benign and Malignant Cutaneous Tumors Using a Deep Learning Algorithm.

We tested the use of a deep learning algorithm to classify the clinical images of 12 skin diseases-basal cell carcinoma, squamous cell carcinoma, intraepithelial carcinoma, actinic keratosis, seborrheic keratosis, malignant melanoma, melanocytic nevus, lentigo, pyogenic granuloma, hemangioma, dermatofibroma, and wart. The convolutional neural network (Microsoft ResNet-152 model; Microsoft Research Asia, Beijing, China) was fine-tuned with images from the training portion of the Asan dataset, MED-NODE dataset, and atlas site images (19,398 images in total). The trained model was validated with the testing portion of the Asan, Hallym and Edinburgh datasets. With the Asan dataset, the area under the curve for the diagnosis of basal cell carcinoma, squamous cell carcinoma, intraepithelial carcinoma, and melanoma was 0.96 ± 0.01, 0.83 ± 0.01, 0.82 ± 0.02, and 0.96 ± 0.00, respectively. With the Edinburgh dataset, the area under the curve for the corresponding diseases was 0.90 ± 0.01, 0.91 ± 0.01, 0.83 ± 0.01, and 0.88 ± 0.01, respectively. With the Hallym dataset, the sensitivity for basal cell carcinoma diagnosis was 87.1% ± 6.0%. The tested algorithm performance with 480 Asan and Edinburgh images was comparable to that of 16 dermatologists. To improve the performance of convolutional neural network, additional images with a broader range of ages and ethnicities should be collected.

Temporal Trends of De Novo Malignancy Development After Heart Transplantation.

BACKGROUND: Malignancy is a concern in cardiac transplant recipients, but the temporal trends of de novo malignancy development are unknown. OBJECTIVES: The goal of this study was to describe the temporal trends of the incidence, types, and predictors of de novo malignancy in cardiac transplant recipients. METHODS: The authors analyzed the temporal trends of post-transplant incidence, types, and predictors of malignancy using 17,587 primary adult heart-only transplant recipients from the International Society for Heart and Lung Transplantation registry. The main study outcomes included the incidence of, types of, and time to de novo malignancy. RESULTS: The risk of any de novo solid malignancy between years 1 and 5 after transplantation was 10.7%. The cumulative incidence by malignancy type was: skin cancer (7.0%), non-skin solid cancer (4.0%), and lymphoproliferative disorders (0.9%). There was no temporal difference in the time to development according to malignancy type. However, the cumulative incidence of de novo solid malignancy increased from 2000 to 2005 vs. 2006 to 2011 (10.0% vs. 12.4%; p < 0.0001). Survival in patients after de novo malignancy was markedly lower than in patients without malignancy (p < 0.0001). Older recipients and patients who underwent transplantation in the recent era had a higher risk of de novo malignancy. CONCLUSIONS: More than 10% of adult heart transplant recipients developed de novo malignancy between years 1 and 5 after transplantation, and this outcome was associated with increased mortality. The incidence of post-transplant de novo solid malignancy increased temporally, with the largest increase in skin cancer. Individualized immunosuppression strategies and enhanced cancer screening should be studied to determine whether they can reduce the adverse outcomes of post-transplantation malignancy.

Histologic analyses on the response of the skin to 1,927-nm fractional thulium fiber laser treatment.

BACKGROUND: The histologic responses to varied parameters of 1,927-nm fractional thulium fiber laser treatment have not yet been sufficiently elucidated. OBJECTIVE: This study sought to evaluate histologic changes immediately after 1,927-nm fractional thulium fiber laser session at various parameters. METHODS: The dorsal skin of Yucatan mini-pig was treated with 1,927-nm fractional thulium fiber laser at varied parameters, with or without skin drying. The immediate histologic changes were evaluated to determine the effects of varying laser parameters on the width and the depth of treated zones. RESULTS: The increase in the level of pulse energy widened the area of epidermal changes in the low power level, but increased the dermal penetration depth in the high power level. As the pulse energy level increased, the increase in the power level under the given pulse energy level more evidently made dermal penetration deeper and the treatment area smaller. Skin drying did not show significant effects on epidermal changes, but evidently increased the depth of dermal denaturation under both high and low levels of pulse energy. CONCLUSION: These results may provide important information to establish treatment parameters of the 1,927-nm fractional thulium fiber laser for various skin conditions.

Clinical and Histological Evaluations of Enlarged Facial Skin Pores After Low Energy Level Treatments With Fractional Carbon Dioxide Laser in Korean Patients.

BACKGROUND: Enlarged facial pores can be an early manifestation of skin aging and they are a common aesthetic concern for Asians. However, studies of improving the appearance of enlarged pores have been limited. OBJECTIVE: The authors aimed to study the application of CO2 fractional laser treatment in patients with enlarged facial pores. METHODS: A total of 32 patients with dilated facial pores completed 3 consecutive sessions of low energy level treatments with a fractional CO2 laser at 4-week intervals. Image analysis was performed to calculate the number of enlarged pores before each treatment session and 12 weeks after the final treatment. RESULTS: After application of laser treatments, there was a significant decrease in the number of enlarged pores. The mean number of enlarged pores was decreased by 28.8% after the second session and by 54.5% at post-treatment evaluation. Post-treatment side effects were mild and transitory. Histological and immunohistochemical analyses demonstrated clear increases in the number of collagen fibers and the expression of transforming growth factor-ß1. CONCLUSION: The short-term results showed that treatment with low energy level CO2 fractional laser therapy could be a safe and effective option for patients with Fitzpatrick skin Types III and IV who are concerned with enlarged pores.

The Basic Mechanism of Hair Growth Stimulation by Adipose-derived Stem Cells and Their Secretory Factors.

BACKGROUND: Adipose-derived stem cells (ADSCs) are mesenchymal stem cells (MSCs) within the stromal vascular fraction of subcutaneous adipose tissue. ADSCs secrete growth factors and other proteins, and have been used to regenerate skin with satisfactory results. OBJECTIVE: This review focuses on the effect of ADSCs and their secretory factors on the stimulation of hair growth in vitro, ex vivo and in vivo. RESULTS: The conditioned media of ADSCs (ADSC-CM) increases the proliferation rate of human follicular cells. ADSCs-derived proteins improve hair growth and protect human dermal papilla cells against cytotoxic injury caused by androgen and reactive oxygen species. Moreover, ADSC-CM induces the anagen phase and promotes hair growth in mice, and enhances the elongation of hair shafts in ex vivo human hair organ cultures. CONCLUSION: ADSC-CM promotes hair growth in vitro, ex vivo, and in vivo. Given that ADSCs are one of the most accessible sources of MSCs, ADSC-derived proteins may be feasible clinical therapeutic agents for the treatment of hair loss.