Pigmentary Changes Research Articles

Evaluation of efficacy and safety of vitiligo treatment with micro-needling combined with N-Acetylcysteine and micro-needling alone: A double-blinded randomized controlled clinical trial.

Vitiligo is a skin pigmentation disorder caused by the selective degradation of melanocytes. This study investigates the therapeutic effects of microneedling with and without N-acetylcysteine (NAC) in patients with persistent and limited vitiligo. This research employed a clinical trial design with double-blind randomization. Individuals affected by vitiligo and seeking treatment at Rasool Akram Medical Complex were divided into two separate treatment groups. In the intervention group, 24 affected areas underwent meso-microneedling using 5% NAC ampoules over six sessions, in addition to the application of 4.7% NAC cream once daily on the specified area. Conversely, the control group, consisting of 22 lesions, underwent microneedling using distilled water during six sessions. The severity of lesions and the extent of repigmentation were gauged using the Modified VETI Score. Assessment of treatment efficacy was determined through both physician evaluations and patient feedback. Twenty patients with a mean age of 36.4 years were recruited. The mean percentage of lesions and their intensity were significantly improved 2 weeks after the third session and 1 month after the end of the treatment (p < 0.01). There was no statistically significant difference between the intervention and control groups. Gender, age, family history, duration of disease, duration of disease stability, and history of hypothyroidism had no statistically significant relationship with patients' treatment outcomes (p > 0.05). Microneedling with or without the application of NAC appears to be an effective treatment option for persistent vitiligo lesions. However, despite the higher improvement rate with the application of NAC, the difference was not significant.

Effect of Temperature on Photosynthetic Pigment Degradation during Freeze–Thaw Process of Postharvest of Celery Leaves

Celery (Apium graveolens L.) is a kind of green leaf vegetable with a large consumption demand in the food industry. It is a commonly used material in quick-frozen food stuffing such as dumplings and steamed stuffed. Fresh celery leaf blades and petioles are rich in photosynthetic pigments including chlorophyll and carotenoid, their contents are closely related to the quality of celery and its products. In order to explore the effects of freezing and thawing temperature and thawing time on the degradation of photosynthetic pigments in celery leaf blades and petioles, the changes in photosynthetic pigments during thawing storage were measured under different freezing and thawing temperatures. The results showed that lower freezing and thawing temperatures were beneficial to the preservation of photosynthetic pigments in celery leaf blades and petioles, and the loss of photosynthetic pigments enhanced with the increase in thawing temperature and thawing time. Under the cold storage condition of −80 °C, the loss rate of pigment substances can be reduced by nearly 20% compared with that of −18 °C, and −80 °C and 4 °C could be the best temperature combination of freezing and thawing. The content and degradation rate of photosynthetic pigments in celery leaf blades were higher than that in petioles during thawing, with a total chlorophyll loss rate reaching 35% during 6 to 12 h after thawing. The increase in temperature difference between freezing and thawing could aggravate the damage to the cell structure and the degradation of the pigment, as chlorophyll is more sensitive to temperature changes, and the degradation rate is significantly higher than that of carotenoids. From the perspective of delaying the degradation of photosynthetic pigments, the results of this study will provide potential references for the reasonable configuration of freezing and thawing temperatures in the process of storage and transportation of celery products.

A 15% Trichloroacetic Acid + 3% Glycolic Acid Chemical Peel Series Improves Appearance of Hand Lentigines: An Evaluator-Blinded, Split-Hand Prospective Trial.

Improving the appearance of lentigines on the hands is a key component to hand rejuvenation. Soft tissue fillers revolumize hands, but do not address pigmentary changes. OBJECTIVE: This study investigated the effiacy of a 15% trichloroacetic acid (TCA) + 3% glycolic acid (GA) combination peel in improvement of appearance of hand lentigines. A prospective evaluator-blinded, split-hand study was performed using a 15% TCA + 3% GA peel to treat patients with hand lentigines. Subjects received a total of 3 treatments at 4-week intervals on 1 hand, with the other hand serving as an untreated control. Final photographs were taken 12 weeks after the last treatment. Two blinded board-certified dermatologists graded improvement in hand lentigines using a 5-point scale. Eighteen of 20 patients completed the study (90%). The mean age was 64.4 years (SE 1.6, range 51-71). The mean pain scores were 3.8 (SE 0.4) on a 10-point scale (1 = no pain, 10 = extremely painful). Blinded evaluators correctly identified the after-treatment photographs in 16 patients (88%). Physician and patient-graded mean improvement of lentigines was significant for treated versus control hands ( p < .01). No adverse events were noted. A series of three 15% TCA + 3% GA peels are effective and safe in the treatment of hand lentigines.

Delayed maturation of the exoskeleton and muscle fibres in the ant Platythyrea punctata

Abstract In many species of eusocial Hymenoptera, workers exhibit a division of labour based on age, wherein young workers remain protected within the nest before transitioning to foraging activities. These changes in tasks and in external stress exposure are accompanied by physiological and anatomical modifications. Although pigmentation changes in the exoskeleton are well documented in ants, limited information is available on muscle morphology and developmental changes in the adult cuticle. Here, we investigated the alterations in the exoskeleton and thoracic muscles across different age groups of the clonal ant Platythyrea punctata, in which reproduction is monopolized by one or a few dominant workers. Our findings revealed a significant thickening of the cuticle and muscle fibres in young workers during the intranidal period, reaching a final stage in forager individuals. We further tested the influence of reproductive status on body development and found variations only in muscle fibres between reproductive and nonreproductive individuals. This suggests that dominant individuals allocate resources in egg-laying by minimizing other metabolic costs. These findings shed light on how eusociality profoundly alters selection pressures and results in temporal shifts in individual development. This strategy probably provides advantages to colonies by minimizing nutritional waste and optimizing resource allocation.

Time-course transcriptome analysis discloses PFDMO2OA (C8 HFPO-TA)-induced developmental malformations and cardiovascular toxicities in zebrafish

PFDMO2OA (C8 HFPO-TA), a novel substitute for perfluorooctanoic acid (PFOA), has been frequently detected in surface waters. However, information on its toxicity remains scarce. In the present study, zebrafish embryos were exposed to varying concentrations of PFDMO2OA, ranging from 80 to 800 mg/L, until 120 h post-fertilization (hpf) to explore its potential developmental toxicities. The LC50 value for mortality was 505.9 mg/L, comparable to that of PFOA (over 500 mg/L), suggesting a lack of safety of PFDMO2OA compared to PFOA. At 120 hpf, PFDMO2OA exposure led to various malformations in embryos, including uninflated swim bladder, yolk sac oedema, spinal deformation, and pigmentation changes, with pericardial oedema being prominent. Analysis using O-dianisidine stain indicated a decline in erythrocytes over time. Transcriptome analysis further revealed the cardiovascular toxicity caused by PFDMO2OA at the molecular level. Time-course differential analysis pointed to the apoptosis dependent on disrupted mitochondrial function as a significant contributor to erythrocyte disappearance, as confirmed by the TUNEL stain. Therefore, the present findings suggest that PFDMO2OA induces developmental malformations and cardiovascular toxicities in zebrafish embryos, demonstrating a toxic potency comparable to that of PFOA. The results further highlight the significance of evaluating the health risks associated with PFDMO2OA.

SPRY1 Deficiency in Keratinocytes Induces Follicular Melanocyte Stem Cell Migration to the Epidermis through p53/Stem Cell Factor/C-KIT Signaling

The function and survival of melanocytes is regulated by an elaborate network of paracrine factors synthesized mainly by epidermal keratinocytes. Keratinocytes and melanocytes respond to UV exposure by eliciting a tanning response. However, how keratinocytes and melanocytes interact in the absence of UV exposure is unknown. Here, we demonstrate that after SPRY1 knockout in epidermal keratinocytes, melanocyte stem cells (McSCs) in the hair follicle exit the niche without depleting the pool of these cells. We also found that McSCs migrate to the epidermis in a p53/SCF/C-KIT-dependent manner induced by a tanning-like response resulting from SPRY1 loss in epidermal keratinocytes. Once there, these cells differentiate into functional melanocytes. These findings provide an example in which the migration of McSCs to the epidermis due to loss of SPRY1 in epidermal keratinocytes and show the potential for developing therapies for skin pigmentation disorders by manipulating McSCs.

EVALUATION OF MACULAR ATROPHY IN PATIENTS TREATED WITH MACULAR BUCKLE FOR MYOPIC TRACTION MACULOPATHY: Mid- and Long-Term Follow-Up.

To evaluate the incidence, rate, and pattern of progression of myopic maculopathy in eyes operated with macular buckle (MB) for myopic traction maculopathy versus a control group without surgery to find out whether the progression varies due to the MB's indentation and to evaluate possible MB-related pigmentary changes or atrophy. Eyes operated with MB with two good quality fundus images: one preoperative or early postoperative image and a second image at least 12 months apart; the control group comprised the contralateral eyes. Demographics, axial length, follow-up, stage of myopic traction maculopathy, and myopic maculopathy were reported. Progression results of groups and subgroups (mid- and long-term follow-up) were reported and compared. Overall, 116 eyes of 66 patients were included. Progression was found in 29 eyes (41.4%) and 23 eyes (50%) in the MB group and control group, respectively. The progression rate was 73 per 1,000 eye-years and 88.9 per 1,000 eye-years in the MB group and the control group, respectively. Axial length was found to predict progression (odds ratio [OR], 2.59; P = 0.02). Progression of myopic maculopathy was similar in both groups and was mildly greater in the control group. No MB-related pigmentary changes or atrophy was detected.

Therapeutic Potential of Fungal Terpenes and Terpenoids: Application in Skin Diseases.

Terpenes and their derivatives comprise a diverse group of natural compounds with versatile medicinal properties. This article elucidates the general characteristics of fungal terpenes and terpenoids, encompassing their structure and biogenesis. The focal point of this work involves a comprehensive overview of these compounds, highlighting their therapeutic properties, mechanisms of action, and potential applications in treating specific skin conditions. Numerous isolated terpenes and terpenoids have demonstrated noteworthy anti-inflammatory and anti-microbial effects, rivalling or surpassing the efficacy of currently employed treatments for inflammation or skin infections. Due to their well-documented antioxidant and anti-cancer attributes, these compounds exhibit promise in both preventing and treating skin cancer. Terpenes and terpenoids sourced from fungi display the capability to inhibit tyrosinase, suggesting potential applications in addressing skin pigmentation disorders and cancers linked to melanogenesis dysfunctions. This paper further disseminates the findings of clinical and in vivo research on fungal terpenes and terpenoids conducted thus far.

Bilateral helicoid peri-papillary sub-retinal fibrosis due to a biallelic NR2E3 mutation: Describing variable expressivity of a mutation.

To describe different clinical presentations of a same NR2E3 recessive mutation in two families and within one family. Interventional family study. Our first case was a one-year-old male child with high hyperopia and refractive accommodative esotropia. In retinal examination, peri-papillary sub-retinal fibrosis with a helicoid configuration was observed in both eyes. The parents and the only sibling had no pathologic findings in the eyes. The child showed to have severely reduced responses in both photopic and scotopic electroretinogram components. In the genetic investigation, a homozygous autosomal recessive mutation in the NR2E3 gene (IVS1-2A > C) was discovered in the affected child, while the other family members were heterozygous for this mutation. We followed up with the patient for 3 years and no new lesion developed during this period. The second case was a 13-year-old male child referred to the retina clinic for decreased vision in the right eye. In retina examination, there were nummular pigmentary changes at the level of retinal pigment epithelium and along the vascular arcades with foveo-schitic changes in both eyes. A choroidal neovascularization (CNV) was noticed in the macula of his right eye. The genetic evaluation proved the same mutation in the NR2E3 gene as in the first case. Family history was remarkable for an uncle, an aunt, and two cousins with night blindness. Same NR2E3 gene mutation can cause heterogeneous clinical manifestations such as slight retinal changes in the absence of any visual symptoms to high hyperopia associated with helicoid peri-papillary sub-retinal fibrosis.

Characterizing differences inoutpatient dermatologic care utilizationamong disaggregated Asian American subgroups.

Despite having significantly higher rates of atopic dermatitis, psoriasis, and pigmentary disorders compared to White patients, studies suggest that Asian Americans are underrepresented in outpatient dermatology clinics. In this study, we utilize the National Health Interview Survey (NHIS) and prioritize disaggregated analyses to evaluate differences between the most populous Asian American subgroups (Chinese, Filipino, Indian, and "Other") in utilization of outpatient dermatologic care. We utilized multivariable logistic regression to compare outpatient dermatologic care use between each Asian American subgroup and Non-Hispanic Whites. Out of 96,559 adults, our study included 5264 self-identified Asian American and 91,295 non-Hispanic White adults. Most Asian participants were female, had health insurance, and had incomes > 2 times above the federal poverty line. We found that, compared to 21.4% for NH whites, lifetime prevalence of total body skin exam was highest among Filipino Americans (12.3%) and lowest among Indian Americans (7%). Additionally, all Asian American subgroups had a significantly lower odd than NH Whites of ever having a total body skin exam, with Indian Americans having the lowest odds. While thebenefitofTBSEs inIndian Americansis unclear,it is possible that differing cultural perceptions about dermatologic needs,barriers to care,orimmigration status may be contributing tothe observed difference. Furthermore, the Indian diaspora encapsulates a range of skin tones, risk factors, and behaviors that maydifferentiallyinfluencedermatologic disease risk,similar totrends identified among Hispanic patients (Trepanowski et al. in J Am Acad Dermatol 88:1206-1209, 2023). Additional researchutilizingthe sevennational databasesthat have been identifiedasprovidingdisaggregated Asian racial information (Kamal et al. in J Am Acad Dermatol, 2023)maybe useful to furtherilluminate avenues for intervention.

Adulticidal synergy of two plant essential oils and their major constituents against the housefly Musca domestica and bioassay on non-target species

Single and mixture formulations of lemongrass (Cymbopogon citratus (DC.) Stapf.) and star anise (Illicium verum (J. Presl.)) essential oils (EOs) and their major constituents were assayed for their adulticidal activities against housefly, Musca domestica L., and two non-target species, stingless bee (Tetragonula pegdeni Schwarz) and guppy (Poecilia reticulata Peters). The efficacies of the mixture formulations were compared against those of the single formulations and 1.0% α-cypermethrin, a common synthetic insecticide. GC-MS analysis found that the major constituent of lemongrass EO was geranial (45.23%), and that of star anise EO was trans-anethole (93.23%). Almost all mixture formulations were more effective in adulticidal activity against housefly adults than single formulations and 1.0% α-cypermethrin. A mixture of 1.0% lemongrass EO + 1.0% trans-anethole exhibited the strongest synergistic insecticidal activity with a 100% mortality rate (KT50 of 3.2 min and LT50 of 0.07 h). The relative percentage increase in mortality rate over single formulations was between 1.6 and 91.9%. In addition, it was three times more effective than 1.0% α-cypermethrin. To find the mechanism of adulticidal action, scanning electron microscopy (SEM) was done to find morphological aberrations, such as antennal and mouthpart aberrations, after the houseflies were treated with 1.0% lemongrass EO + 1.0% trans-anethole. The aberrations included deformed and abnormal shape of arista and flagellum, change in labellum pigmentation, and damage to pseudotracheae. Regarding toxicity against non-target species, all single and mixture formulations were not toxic to the two non-target species, while 1.0% α-cypermethrin was highly toxic. To conclude, a mixture of 1.0% lemongrass EO + 1.0% trans-anethole can be an excellent, natural, sustainable housefly adulticidal agent.

Novel 532-nm Q-switched Nd: YAG laser for the treatment of melasma and rejuvenation: a prospective, randomized controlled comparison with 1,064-nm Q-switched Nd: YAG laser.

Melasma is a common pigmentary and photoaging disorder. Although various treatments, including 1,064-nm Q-switched neodymium-doped yttrium aluminum garnet (QS-Nd: YAG) laser toning, are available for melasma, results are often unsatisfactory. We aimed to determine the efficacy and safety of 532-nm QS-Nd: YAG laser (shortwave toning) in patients with melasma and facial rejuvenation. Fifty-two patients were recruited to receive either 1,064-nm QS-Nd: YAG laser or 532-nm QS-Nd: YAG laser every 2 weeks for 8 sessions and a 2-month follow-up visit in a randomized controlled double-blinded study. The primary outcome measure was the Melasma Area and Severity Index (MASI) score. Dermoscope and high-frequency ultrasound (HFUS) were used to assess the improvement of melasma and photoaging. 532-nm QS-Nd: YAG laser achieved significantly higher improvement in the MASI score (P = 0.000). The Dermoscopic melasma score (DMS) displayed significant change and confirmed the improvement. HFUS showed a significant decrease in the thickness of the subepidermal low-echogenic band (SLEB) and increases in dermal thickness and dermal density in both groups (P = 0.000 for all). The rate of very satisfied responses was significantly higher in the 532-nm laser group (P = 0.001). There was no significant difference in the visual analog scale pain assessment score (P = 0.248) and recurrence rate (P = 0.734) between the two groups. 532-nm QS-Nd: YAG laser (shortwave toning) proved to be an effective and safe treatment for melasma and rejuvenation. Shortwave toning was significantly better for pigmentation clearance, while 1,064-nm laser showed better improvement in skin rejuvenation.

Therapeutic Approach in Pigmented Purpuric Dermatoses-A Scoping Review.

Pigmented purpuric dermatoses (PPD) encompass a group of chronic skin conditions characterized by the presence of petechiae, purpura, and pigmentation changes. While generally benign, these dermatoses can be persistent and aesthetically bothersome. Key clinical features include red to brownish patches with a distinctive "cayenne pepper" appearance, predominantly localized on the lower extremities, particularly the shins. Subtypes include Schamberg disease, Majocchi's disease, Gougerot-Blum disease, Ducas and Kapetanakis pigmented purpura, and lichen aureus. Diagnosis relies primarily on clinical evaluation of skin lesions, with biopsy as a confirmatory tool. Although the exact cause of PPD remains unclear, capillary fragility and red blood cell extravasation are implicated. Treatment strategies for PPD aim to alleviate symptoms, considering the generally benign and chronic nature of the condition. As there is no standardized treatment, various methods with varying efficacy are employed. After searching SCOPUS and PubMed databases, we assessed 42 original articles to present current knowledge regarding therapy of PPD. This review will compare treatment approaches specifically in Schamberg disease and other manifestations of pigmented purpuric dermatoses.

Toxicological properties of plant-based disinfectants

The article presents the results of research on the toxicity determination of phytopreparations in the composition of common powdery mildew + calamus + pear Late November + bischofite; common powdery mildew + calamus + bischofite; pear Late November + bischofite, which have a universally broad spectrum of bactericidal action against Staphylococcus aureus and Escherichia coli. When studying the toxicity of phytopreparations on guppy fish, it was found that when adding the infusion to water in the composition of common powdery mildew + calamus + pear Late November + bischofite with exposures of 30 minutes and 60 minutes, all fish in a group of 10 had an adverse reaction. With an exposure of 24 hours, mortality reached up to 20 %. The highest fish mortality occurred at 24 hours in the composition of common powdery mildew + calamus + bischofite, with a mortality rate of 40 %. The composition of pear in late November + bischofite showed no signs of toxicity; all fish in the group remained alive during the study. Visually, motor activity, behavioral reactions, changes in skin pigmentation, and breathing intensity were average. The survey of skin-irritating effects of phytopreparations was conducted on laboratory animals in 20 individuals – Alaska breed rabbits. It was established that during the observation period, the following signs were absent: the presence of temperature; moderately expressed, expressed, and sharply expressed erythema; pain (with a slight thickening of the skin followed by flaking); pain, swelling, and ulcers (thickening of the skin in the application area on the rabbit). After applying phytopreparations to the skin of rabbits with exposures of 1 hour, 24 hours, 48 hours, and 72 hours, no behavioral and visual changes of an inflammatory nature were detected. When applied to the animal's skin, the investigated plant-based disinfectants do not cause irritating, necrotic, or absorptive effects. Throughout the observation period, no visible changes were observed in laboratory animals' experimental and control groups. The conducted research indicates the possibility of safe application of these plant-based disinfectants in the presence of animals.

Efficacy and Safety ofAblativeFractionalLaser in Melasma: A Meta-analysis and Systematic Review.

Melasma is a common acquired skin pigmentation disorder. The treatment is urgent but challenging. Ablative fractional laser (AFL) can improve pigmentation, but the efficacy and potential side effects are still debatable. This study aimed to evaluate the efficacy and safety of ablative fractional lasers in the treatment of melasma. A comprehensive systematic search of literature published before June 20, 2023, was conducted on online databases, including PubMed, Embase, Cochrane Library, and Web of Science. The data obtained were analyzed using Review Manager 5.4 software. Fourteen randomized controlled trials, comprising 527 patients, were included. Compared to the drug alone, the combination of AFL and the drug showed improved therapeutic efficacy in the melasma area and severity index (MASI) (MD = 1.54, 95% CI [0.16, 2.92], P = 0.03) and physician global assessment (RR = 1.61, 95% CI [1.08, 2.41], P = 0.02). However, no statistically significant results were found in patient self-assessment (RR = 1.56, 95% CI [0.88, 2.76], P = 0.12). As an individual therapy, AFL is not superior to any other lasers in terms of MASI (MD = 2.66, 95% CI [-1.32, 6.64], P = 0.19) or melanin index (MD = -7.06, 95% CI [-45.09, 30.97], P = 0.72). Common adverse events included transient erythema, burning, edema, and superficial crusting. Only a few patients experienced reversible post-inflammatory hyperpigmentation, herpes labialis, and acne breakouts. These results support the application of AFL as a viable treatment option for melasma, particularly in refractory and severe cases. Rational parameterization or combination therapy may lead to significant clinical improvement with fewer complications.

Feasibility of High-Cellular-Resolution Full-Field, Artificial-Intelligence-Assisted, Real-Time Optical Coherence Tomography in the Evaluation of Vitiligo: A Prospective Longitudinal Follow-Up Study.

Vitiligo, a psychologically distressing pigmentary disorder characterized by white depigmented patches due to melanocyte loss, necessitates non-invasive tools for early detection and treatment response monitoring. High-cellular-resolution full-field optical coherence tomography (CRFF-OCT) is emerging in pigmentary disorder assessment, but its applicability in vitiligo repigmentation after tissue grafting remains unexplored. To investigate the feasibility of CRFF-OCT for evaluating vitiligo lesions following tissue grafting, our investigation involved ten vitiligo patients who underwent suction blister epidermal grafting and laser ablation at a tertiary center between 2021 and 2022. Over a six-month period, clinical features, dermoscopy, and photography data were recorded. Utilizing CRFF-OCT along with artificial intelligence (AI) applications, repigmentation features were captured and analyzed. The CRFF-OCT analysis revealed a distinct dark band in vitiligo lesion skin, indicating melanin loss. Grafted areas exhibited melanocytes with dendrites around the epidermal-dermal junction and hair follicles. CRFF-OCT demonstrated its efficacy in the early detection of melanocyte recovery and accurate melanin quantification. This study introduces CRFF-OCT as a real-time, non-invasive, and in vivo evaluation tool for assessing vitiligo repigmentation, offering valuable insights into pigmentary disorders and treatment responses.

The Yucatan miniature swine as a model for post-inflammatory hyperpigmentation.

Post-inflammatory hyperpigmentation (PIH) is a hypermelanosis that often occurs secondary to skin irritation or injury, especially in darker skin tones, for which there is currently a lack of effective treatment options. Few preclinical models are available to study PIH. Here, we show that the Yucatan miniature pig consistently develops PIH after skin injuries. Skin wounds were produced on Yucatan pigs by needle punches, full-thickness excisions, or burns. Wound sites were monitored and photographed regularly. Tissue samples were collected after 24 weeks and processed for histology/immunohistochemistry. Skin pigmentation and histologic changes were quantified by computer-assisted image analyses. All injury methods resulted in hyperpigmentation. Melanin content at the histologic level was quantified in the larger (burn and excision) wounds, showing a significant increase compared to uninjured skin. Increased melanin was found for both epidermal and dermal regions. Dermal melanin deposits were primarily clustered around the papillary vasculature, and were associated not with melanocytes but with leukocytes. The Yucatan miniature pig model recapitulates key clinical and histologic features of PIH in humans, including skin hyperpigmentation at both gross and histologic levels, and persistence of dermal melanin subsequent to injury. This model could be used to further our understanding of the etiology of PIH, and for new therapy development.

Comparison of efficacy and safety of tretinoin 0.05% and glycolic acid peeling 70% in axillary and neck lesions of acanthosis nigricans: A single-blinded, randomized trial.

Acanthosis nigricans is a non-inflammatory skin pigmentary disorder characterized by a dark, velvety appearance, primarily observed in the neck and axillary areas. It is commonly associated with obesity, diabetes, and insulin resistance. Although the primary treatment is correcting the underlying disorders, many aesthetic modalities have been established to improve appearance owing to cosmetic concerns. We aimed to compare and investigate the effectiveness and side effects of tretinoin 0.05% and glycolic acid 70% in treating acanthosis nigricans lesions of the axillary and neck area. This single-blinded, randomized trial recruited patients with neck or axillary involvement. Each patient was randomized to use cream tretinoin 0.05% every other night on one side, while the other side was treated with glycolic acid 70%, which was applied every 2 weeks at the clinic for four consecutive sessions. The study duration was 8 weeks, and patients were evaluated every 2 weeks based on their response to treatment, satisfaction, and side effects. Thirty patients, including 14 with neck lesions and 16 with axillary lesions, were included. Tretinoin was significantly more effective for axillary lesions in terms of treatment response and patient satisfaction (p = 0.02 and p = 0.008, respectively). It was also shown that as the severity of the lesions increased, the response to treatment and patient satisfaction decreased, specifically when treating axillary lesions with glycolic acid (p = 0.02 and p = 0.03, respectively). Neither method was significantly effective for neck lesions. However, tretinoin 0.05% was shown to be more efficacious in treating axillary lesions of acanthosis nigricans, despite causing minimal side effects.

567 - Prognostic factors in pediatric patients with vitiligo

Abstract Introduction Vitiligo is a pigmentary disorder, and its prevalence reaches 2.16% in children.(1) Childhood vitiligo differs from adult vitiligo in clinical characteristics such as higher incidence in females, higher prevalence of segmental presentation and lower association with autoimmune disorders. (2) The course of vitiligo is unpredictable, the disease may regress, stabilize, progress and exacerbate. (3) Few studies of the course of vitiligo have been published. Objectives The aim of this study was to identify the clinical characteristics associated with the progression of vitiligo in children and adolescents and also to describe the epidemiological profile in our patients. Methods We analyzed the clinical records of a cohort of pediatric patients with vitiligo attended at Centro Dermatológico Dr. Ladislao de la Pascua in Mexico City. Vitiligo diagnosis was defined clinically and to classify patients with NSV we used the revised classification of the Vitiligo Global Issues Consensus Conference. The outcome was the progression of vitiligo, and it was defined as an increase in the extent of the disease at the last visit of follow-up of the patient. We extracted the following data: age at onset, presence of halo nevus, Koebner phenomenon, familial medical history of vitiligo, presence of autoimmune and thyroid disorders. The Koebner phenomenon was considered if lesions were present in areas of friction or if the parents reported their occurrence at sites of previous trauma. Statistical analysis was performed using software SPSS v.25. To calculate the follow-up time we calculate the number of days between the last visit to the first visit of the participant to the center. We define four states according to the clinical course of vitiligo: stable, partial remission, complete remission and progressión. Stable means that the affected body surface area (BSA) did not change over the time, partial remission that the BSA decreased, complete remission means a BSA equal to zero and progression an increase in the involved BSA. We made a survival analysis using Kaplan Meier curves. Results Of the 679 participants, 50.2% (341) were males and 49.8% (338) females, giving a male-to-female ratio of 1:1. The average age of onset was 8.6 years (SD 4.4 years). Non-segmental vitiligo (NSV) was more common (55.5%) than segmental vitiligo (44.5). Koebner’s phenomenon was observed in 22.5% of patients and halo nevus was diagnosed in 5% of them. Only 4.1% (28) of the patients had family history of vitiligo; 0.9% had thyroid disorders and 0.3% had been diagnosed with an autoimmune disorder. The mean time of follow up was 11 months. The clinical course of the patients was: stable 44.3%, partial remission 38.7%, complete remission 4.9% and progression in 12.1%. The median time to progression of vitiligo was 71 months equivalent to 5.9 years (95%CI 58.72-83.29 months). The mean time to progression for non-segmental vitiligo was 54.94 months vs. 61.94 patients with segmental vitiligo (p=0.087). Time to progression was different in patients with another skin disease 68.37 months vs. 54.53 months (p=0.015). There were no differences in time to progression for the following variables: treatment, age of onset, gender, family history, Koebner phenomenon, halo nevus and autoimmune disorders. Conclusions In our population childhood vitiligo has a slow progression rate and a low prevalence of family history and Koebner's phenomenon compared to other Latin American populations. (4) The ratio of non-segmental to segmental vitiligo and female to male were lower than other countries. (5) Studies with longer follow-up periods are needed to assess progression in vitiligo.

A microRNA focus on acne.

Acne (syn. acne vulgaris) is a common inflammatory skin disorder associated with puberty and adolescence. The disease is characterized by comedoneous lesions, papules, pustules, and nodules that are mostly found on the face. These lesions are caused by intricate interactions between the pilosebaceous unit and the Cutibacterium acnes (C. acnes) bacteria. Unhealthy acne and its aftereffects, like pigment changes and scarring, have a detrimental impact on one's quality of life. Recent years have seen a sharp increase in the approval of nucleic acid therapies (NATs), such as antisense oligonucleotides and short-interfering RNA medications, for rare diseases for which there are few or no effective treatments. These developments suggest that NATs may be useful in acne treatment plans down the road, as do clinical trials for microRNA (miRNA) modulation in skin contexts. We highlight promising miRNA targets for anti-acne therapy in this review. We outline the pathophysiology of acne in brief and emphasize the functions of C. acnes. Next, we concentrate on the distinct impacts of biofilm and planktonic C. acnes on a Toll-like receptor 2 axis that spans miR-146a-5p, which was recently discovered. Before discussing the potential contributions of miR-21-5p, miR-233-3p, and miR-150-5p to inflammatory axes in acne, we evaluate miR-146a-5p in sebocytes. Finally, we address patient involvement in miRNA-related acne research and translational perspectives.