Hair follicles are skin appendages with a complex structure and periodical self-renewal ability. The hair follicle cycle includes the anagen phase, catagen phase and telogen phase, and its orderly renewal is important to maintain hair growth. It is currently believed that Wnt, bone morphogenetic protein, and Notch signaling pathways are involved in regulating the hair follicle cycle. As research progresses, various regulatory mechanisms based on these signaling pathways have been gradually revealed, such as growth factors, non-coding RNAs, immune responses, etc. This review elaborates on the above molecular mechanisms and regulatory modalities, aiming to promote better understandingn of regulatory mechanisms underlying the hair follicle cycle and provide a theoretical reference for expanding treatment options for hair loss.

Hair follicles are complex organs consisting of multiple cell types. Single-cell sequencing technology can identify the transcriptional characteristics of various cell types and subsets in tissues at the single-cell level, comprehensively revealing the heterogeneity among cell populations. This review focuses on the latest advances in the application of single-cell sequencing to the study on molecular characteristics of mouse and human hair follicle cells and cell fate regulation, as well as aging, microbial symbiosis, and the pathogenesis of hair loss and hair graying. Single-cell sequencing can serve as a novel tool for studying the morphogenesis, cell types, physiological and pathological states of hair follicles, and has revealed important information that had not been found in traditional research, which is meaningful for hair-related studies.

A 58-year-old female patient presented with erythema on the right shoulder and chest for 8 years. The appearance of erythema was concurrent with numbness and weakness in both lower limbs, elevated peripheral blood M protein levels, thyroid dysfunction, and multiple enlarged lymph nodes in the right axilla, leading to a diagnosis of POEMS syndrome. After autologous hematopoietic stem cell transplantation, erythema subsided but recurred 1 year prior to this visit. Physical examination revealed a pigeon egg-sized swollen lymph node on the right side of the neck. Skin examination showed patchy erythema on the right shoulder and chest, with clear boundaries and a hard texture. Serum protein electrophoresis revealed an elevated M protein level, and serum immunofixation electrophoresis showed a restricted IgG λ band. In addition, peripheral blood levels of vascular endothelial growth factor were elevated. Computed tomography scan images showed an irregular flaky bone destruction area at the acromion end of the right scapula, which was consistent with the manifestations of bone plasmacytoma. Histopathological examination of the skin tissue in the right shoulder revealed a large number of dilated and proliferative vessels between dermal collagen fibers, and the patient was diagnosed with AESOP syndrome. Lenalidomide combined with dexamethasone chemotherapy was administered. After three cycles of treatment, M protein turned negative, and erythema became darker in color, and decreased in size compared with the skin lesion before treatment.

Stem cells are a kind of cells with the ability of self-renewal and differentiation, which can differentiate into melanocytes to fill the areas of pigment loss in damaged skin, fight against the apoptosis of melanocytes caused by autoimmunity and oxidative stress damage, and improve repigmentation rates in combination with traditional therapies. Studies have shown significant efficacy of stem cell therapy in the repigmentation of vitiligo. This review summarizes the latest advances in the basic and clinical research on the application of stem cells in the treatment of vitiligo.

Objective:To evaluate the cosmetic effect of facial melanocytic nevus excision along the pigmented contours.Methods:A total of 318 patients with facial melanocytic nevi were collected from the Department of Burns and Plastic Surgery, the Affiliated Yongchuan Hospital of Chongqing Medical University from October 2018 to August 2020. The patients collected after October 2019 underwent contoured excision of facial melanocytic nevi (observation group), while those collected before October 2019 underwent fusiform excision of lesions (control group). Recurrence rates, wound lengths, and scar conditions were compared between the two groups one year after surgery. Comparisons of measurement data between the two groups were conducted using the t test. Results:The observation group included 159 patients (372 melanocytic nevi), comprising 24 males and 135 females, aged from 15 to 45 (25.4 ± 6.5) years; the short diameters of the melanocytic nevi ranged from 2 to 6 (3.9 ± 0.6) mm, and the long diameters ranged from 2 to 8.5 (4.3 ± 0.7) mm. The control group consisted of 159 patients (390 melanocytic nevi), including 29 males and 130 females, aged from 16 to 48 (26.3 ± 7.3) years; the short diameters of the melanocytic nevi ranged from 2 to 6 (3.7 ± 0.8) mm, and the long diameters ranged from 2.2 to 8.4 (4.5 ± 0.5) mm. There were no significant differences in age, gender composition, or short and long diameters of the melanocytic nevi between the two groups (all P > 0.05). After one year of follow-up, 4 patients experienced recurrence in the observation group, and 3 experienced relapse in the control group; the scar scores were 0.64 ± 0.24 points in the observation group and 0.58 ± 0.19 points in the control group, and there were no significant differences in the recurrence rates or scar scores between the two groups (both P > 0.05) ; the increase in wound length was significantly lower in the observation group (27.44% ± 8.46%) than in the control group (48.42% ± 38.84%, t = 10.19, P = 0.004) . Conclusion:Compared with the fusiform excision technique, the pigmented contoured excision technique showed similar efficacy for the treatment of facial melanocytic nevi, but resulted in shorter wound lengths.

Blueberry muffin baby refers to the newborn with extensive purple and purplish-red round or oval macules, papules and nodules, and is the phenotype of various diseases. However, the symptoms of neonatal diseases are atypical, the condition changes rapidly, and the diagnosis is very challenging. To date, there have been very few research publications on blueberry muffin baby in China and other countries. This review summarizes the diseases that can manifest as blueberry muffin-like lesions, aiming to assist clinical practice and scientific research.

Objective:To investigate the clinical efficacy and safety of different combination therapies with aminolevulinic acid photodynamic therapy (ALA-PDT) in the treatment of facial basal cell carcinoma in the elderly.Methods:A retrospective analysis was conducted on 131 elderly patients with facial basal cell carcinoma who visited Shanghai Skin Disease Hospital from August 2020 to October 2023. According to the depth of the lesions, the patients were divided into 3 groups to receive intensive pretreatment with curettage (41 cases), CO 2 laser therapy (35 cases), and narrow-margin excision surgery without sutures (55 cases) respectively, all followed by ALA-PDT. During the follow-up period of 17.7 ± 9.0 months, the efficacy was evaluated and adverse reactions were recorded in each group. Results:The total remission rates were 100%, 100%, and 96.4% in the curettage + ALA-PDT group, CO 2 laser + ALA-PDT group, and narrow-margin excision surgery without sutures + ALA-PDT group, respectively. The patients experienced mild pain and local erythematous swelling during ALA-PDT treatment, which were temporary and fully tolerable, and no wound infections or difficulties in healing were observed. After treatment, scar formation was observed in 3 cases of basal cell carcinoma on the nose and nasolabial folds in the narrow-margin excision surgery without sutures + ALA-PDT group, but the rest of the patients retained a good facial appearance. Conclusions:In this preliminary exploration study on PDT for basal cell carcinoma of different depths, ALA-PDT combined with curettage, CO 2 laser or narrow-margin excision surgery without sutures all exhibited definite efficacy and minimal damage, providing effective treatment options for facial basal cell carcinoma in the elderly.

Objective:To analyze the differences in clinicopathological features between non-elderly and elderly patients with melanoma, and to identify risk factors for prognosis in elderly patients with melanoma.Methods:A retrospective analysis was conducted on clinical and pathological data collected from non-elderly (aged < 60 years) and elderly (aged ≥ 60 years) patients with melanoma, who were confirmedly diagnosed according to clinical manifestations and histopathological findings at the People's Hospital of Xinjiang Uygur Autonomous Region from January 2008 to December 2023. The differences in clinical and pathological characteristics between the two groups were analyzed using the chi-square test and Wilcoxon rank-sum test. Survival curves were estimated using the Kaplan-Meier method and log-rank test. The relationship between clinicopathological variables and overall survival was analyzed using a Cox regression model.Results:A total of 233 patients with cutaneous melanoma were included, with the age being 60.3 ± 14.7 years, and the number of patients was highest in the age group of 60 - 69 years. There were 102 cases (43.8%) in the < 60 years old group and 131 cases (56.2%) in the ≥ 60 years old group. Compared with the < 60 years old group, the ≥ 60 years old group showed a significant increase in the proportion of patients with active tumor-infiltrating lymphocytes ( P = 0.040), proportion of those with Ki-67 index ≥ 30% ( P = 0.010), and Charlson comorbidity index ( P = 0.002), but a significant decrease in the proportion of patients with BRAF/KIT/NRAS mutations ( P = 0.003), proportion of those receiving surgical treatment ( P = 0.034), and proportion of those receiving adjuvant therapy ( P = 0.042). There was a significant difference in the overall survival between the two groups (log-rank test, χ2 = 6.10, P = 0.014). The gender, metastasis status, presence or absence of ulceration, distant metastasis status, American Joint Committee on Cancer staging, Charlson comorbidity index, and Breslow thickness were important prognostic indicators affecting the overall survival in the elderly patients with melanoma. Multivariate Cox regression analysis showed that males ( P = 0.015, HR = 4.622, 95% CI: 1.352 - 15.798), presence of distant metastasis ( P = 0.013, HR = 9.844, 95% CI: 4.621 - 59.763), and Charlson comorbidity index ≥ 3 ( P = 0.038, HR = 3.149, 95% CI: 1.067 - 9.294) were independent risk factors affecting the overall survival in the elderly patients with melanoma. Conclusions:Compared with the non-elderly patients with melanoma, a higher Ki-67 index, a higher Charlson comorbidity index, less surgical treatment, and less adjuvant therapy were more common in the elderly patients with melanoma. Males, the presence of distant metastasis, and Charlson comorbidity index ≥ 3 appeared to be independent risk factors affecting the overall survival in the elderly patients with melanoma.

Objective:To retrospectively analyze the clinical efficacy and safety of biological agents in the treatment of psoriasis in the elderly.Methods:A retrospective study was conducted. A total of 124 patients aged ≥ 65 years with moderate-to-severe psoriasis (psoriasis area and severity index [PASI] score ≥ 3 points or body surface area [BSA] ≥ 3%), who were treated with biological agents at the Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, from June 2020 to December 2023, were collected. PASI, BSA, and dermatology life quality index (DLQI) scores were recorded at weeks 0 (pre-treatment), 4, 12, and 24 after the beginning of treatment to evaluate the efficacy. The proportions of patients achieving ≥ 75% and 90% improvements in PASI scores (PASI75 and PASI90, respectively) were calculated, and adverse reactions were recorded. Data were processed using SPSS 29.0 and GraphPad Prism 10.0 software. Normally distributed continuous variables were presented as mean ± standard deviation, while non-normally distributed continuous variables were presented as median with upper and lower quartiles ( Q1, Q3). Wilcoxon signed-rank test was used for comparisons of non-normally distributed data between groups, and chi-square test and Fisher's exact test were used for comparing categorical data. Results:Among the 124 patients, there were 72 males (58.1%) and 52 females (41.9%), and their ages ranged from 65 to 87 years. Treatment regimens included secukinumab for 86 patients (69.4%), ustekinumab for 15 (12.1%), ixekizumab for 14 (11.3%), guselkumab for 5 (4.0%), and adalimumab for 4 patients (3.2%). The pre-treatment PASI, BSA, and DLQI scores [ M ( Q1, Q3) ] were 12.2 (7.8, 19.6) points, 16.0% (10.2%, 25.0%), and 16 (11, 20) points respectively, which significantly decreased to 0.8 (0, 1.2) points, 1.0% (0, 2.0%), and 0 (0, 3) points respectively at week 24 after the start of treatment ( Z = 9.66, 9.66, 9.63, respectively, all P < 0.01). The proportions of patients achieving PASI75 at weeks 4, 12, and 24 were 42.7% (53/124), 80.6% (100/124), and 93.5% (116/124) respectively, and those achieving PASI90 were 13.7% (17/124), 48.4% (60/124), and 85.5% (106/124) respectively. There were no significant differences in the proportions of patients achieving PASI75 and PASI90 between the subgroups with and without comorbidities, as well as between the early-onset psoriasis subgroup and late-onset psoriasis subgroup at weeks 4, 12, and 24 (all P > 0.05). Among the 124 patients, 42 were followed up for over 2 years, and the proportions of patients achieving PASI75 and PASI90 after 2 years of treatment were 71.4% (30 cases) and 54.8% (23 cases), respectively. Adverse reactions occurred in 13 patients, including upper respiratory infections in 4 patients (3.2%), elevated aminotransferase levels in 3 patients (2.4%), eczematoid dermatitis in 2 patients (1.6%), pruritus in 2 patients (1.6%), nodular prurigo in 1 patient (0.1%), and vitiligo in 1 patient (0.1%) . Conclusion:Biological agents showed rapid and marked efficacy in the treatment of moderate-to-severe psoriasis in the elderly, with few and mild adverse reactions, suggesting high safety and overall marked efficacy.

Objective:To evaluate the efficacy and safety of a Chinese herbal mask in the treatment of melanized-type melasma by stereological measurements.Methods:A randomized, controlled, evaluator- and statistician-blind clinical study was conducted. A total of 116 patients with melasma who met the inclusion and exclusion criteria were selected and equally divided into two groups by using a random number table method, with 58 patients in each group. The treatment group received topical treatment with a Chinese herbal mask once a night, while the control group received topical hydroquinone cream in the morning and evening twice daily. The course of treatment lasted 12 weeks, with follow-ups every 4 weeks, and an additional follow-up was performed 12 weeks after discontinuation of treatment. A facial image analyzer and a reflectance confocal microscopy (RCM) were used to collect images before and after treatment. Melasma area and severity index (MASI) scores and RCM scores served as outcome measures, and stereological measurement methods were employed to compare scores before and after treatment; response rates and recurrence rates were calculated, and adverse reactions were observed and recorded. Statistical analyses were performed using the chi-square test and t test. Results:A total of 54 patients in the treatment group and 47 patients in the control group completed the study. After 4- and 8-week treatment, there were no significant differences in MASI scores or RCM scores between the two groups (all P > 0.05) ; after 12-week treatment, the MASI scores and RCM scores were significantly lower in the treatment group (2.91 ± 1.16, 5.48 ± 1.60, respectively) than in the control group (3.99 ± 2.03, 6.66 ± 1.88, t = -3.32, -3.37, respectively, both P < 0.01). After the end of treatment, there was no significant difference in the response rate between the treatment group (44/54, 81.5%) and the control group (34/47, 72.3%; χ2 = 0.12, P > 0.05). Twelve weeks after discontinuation of treatment, 2 patients (3.7%) relapsed in the treatment group, while 15 (31.9%) relapsed in the control group, showing a significant difference in recurrence rates between the two groups ( χ2 = 12.34, P < 0.01). Adverse reactions occurred in 2 patients (3.7%) in the treatment group and 6 (11.5%) in the control group, and there was no significant difference in the incidence of adverse reactions between the two groups ( χ2 = 1.34, P > 0.05) . Conclusions:The Chinese herbal mask was safe and effective in the treatment of melanized-type melasma. The application of the facial image analyzer and RCM technology in combination with stereological measurement methods has certain value in reducing the subjectivity in efficacy evaluation for melasma.