Non-invasive imaging of pathological scars using a portable handheld two-photon microscope.

BACKGROUND: Pathological scars are a disorder that can lead to various cosmetic, psychological, and functional problems, and no effective assessment methods are currently available. Assessment and treatment of pathological scars are based on cutaneous manifestations. A two-photon microscope (TPM) with the potential for real-time non-invasive assessment may help determine the under-surface pathophysiological conditions in vivo . This study used a portable handheld TPM to image epidermal cells and dermal collagen structures in pathological scars and normal skin in vivo to evaluate the effectiveness of treatment in scar patients. METHODS: Fifteen patients with pathological scars and three healthy controls were recruited. Imaging was performed using a portable handheld TPM. Five indexes were extracted from two dimensional (2D) and three dimensional (3D) perspectives, including collagen depth, dermo-epidermal junction (DEJ) contour ratio, thickness, orientation, and occupation (proportion of collagen fibers in the field of view) of collagen. Two depth-dependent indexes were computed through the 3D second harmonic generation image and three morphology-related indexes from the 2D images. We assessed index differences between scar and normal skin and changes before and after treatment. RESULTS: Pathological scars and normal skin differed markedly regarding the epidermal morphological structure and the spectral characteristics of collagen fibers. Five indexes were employed to distinguish between normal skin and scar tissue. Statistically significant differences were found in average depth ( t = 9.917, P <0.001), thickness ( t = 4.037, P <0.001), occupation ( t = 2.169, P <0.050), orientation of collagen ( t = 3.669, P <0.001), and the DEJ contour ratio ( t = 5.105, P <0.001). CONCLUSIONS: Use of portable handheld TPM can distinguish collagen from skin tissues; thus, it is more suitable for scar imaging than reflectance confocal microscopy. Thus, a TPM may be an auxiliary tool for scar treatment selection and assessing treatment efficacy.

Efficacy and safety of 1565-nm nonablative fractional laser combined with mucopolysaccharide polysulfate cream for erythematous acne scars.

PURPOSE: To evaluate the efficacy and safety of 1565-nm nonablative fractional laser (NAFL) combined with mucopolysaccharide polysulfate (MPS) cream in the treatment of erythematous acne scars. METHODS: A total of 28 subjects with erythematous acne scars from June 2021 to April 2022 were enrolled. One side of each subject's face was randomly assigned to be treated with 1565-nm NAFL (at 2 sessions with four-week intervals) combined with MPS cream (twice daily) for 8 weeks, and the other side with 1565-nm NAFL combined with placebo cream. CBS® images and parameters, dermoscopic images and the quantitative data processed by ImageJ software, and quantitative global scarring grading system (GSS) score were obtained at baseline and after treatment. Subjects' satisfaction assessment was performed after treatment. Adverse events were recorded during treatment. RESULTS: In CBS® parameters, the red area, red area concentration, and smoothness were improved more significantly on the 1565-nm NAFL combined with MPS cream side than on the 1565-nm NAFL combined with placebo cream side after treatment (p = 0.015, p = 0.013, and p = 0.021). For dermoscopy, both scar area and scar redness achieved a significantly greater percentage of improvement on the side of 1565-nm NAFL combined with MPS cream than the side of 1565-nm NAFL combined with placebo cream after treatment (p = 0.005 and p = 0.041). The reduction of quantitative GSS score and Subjects' satisfaction assessment were similarly superior on the 1565-nm NAFL combined with MPS cream side. Temporary erythema was experienced by all subjects after each 1565-nm NAFL treatment. No subject reported intolerance or allergy to the cream during follow-up. CONCLUSIONS: The combined application of 1565-nm NAFL and MPS cream could be an effective and safe treatment for erythematous acne scars. ImageJ software enables quantitative evaluation of dermoscopic images of acne scars.

Clinical efficacy of LED golden light combined with acyclovir in the treatment of herpes zoster: a single-center prospective study.

This study aimed to explore the safety and clinical efficacy of light emitting diode (LED) golden light combined with acyclovir in treating herpes zoster (HZ). According to the random number table, 54 inpatients with HZ were divided into control group, golden-light group, and red-light group, with 18 cases in each group. The control group received acyclovir intravenous drip, while the patients in the red-light group received acyclovir intravenous drip and red-light LED phototherapy, and the golden-light group received acyclovir intravenous drip and golden-light LED phototherapy. Primary assessments included herpes stopping time, incrustation time, decrustation time, pain visual analog scale scores (VAS), and incidence of postherpetic neuralgia (PHN) on the 30th and 90th days. Golden-light group and red-light group showed a shorter herpes stopping time, incrustation time, and decrustation time (P < 0.05) compared to the control group (P < 0.05), while the golden-light group showed a shorter incrustation time and decrustation time than the red light group (all P < 0.05). After treatment VAS scores, the golden-light group showed a significant improvement compared to the control group. The golden-light group showed a better PHN incidence than the control group at 30 days follow-up. Compared with the comprehensive curative effect, the total effective rates of the golden-light group, red-light group, and control group were 88.89%, 77.78%, and 72.22%, respectively, and the efficacy of the golden-light group was better than that of the control group and red-light group. Golden light combined with acyclovir can shorten the course of HZ, relieve pain, and reduce the occurrence of PHN, and the effect is better than that of the red-light group and the control group.

Dermoscopy in Mycobacterium marinum infection and its correlation with clinical and histopathological features: a prospective observational study.

BACKGROUND: Mycobacterium marinum is a nontuberculous mycobacterium and a conditional pathogen to humans, which can be inoculated directly and cause chronic skin granulomas. Dermoscopy has been applied to other granulomatous skin diseases, but not to M. marinum infection. AIM: To explore the dermoscopic features of M. marinum infection, and its correlation with clinical and histopathological features. METHODS: In total, 27 lesions from 27 patients (19 women, 8 men, age range 28-71 years) diagnosed with M. marinum infection were identified by clinical examination, histopathological results, PCR sequencing and mycobacterial culture in the dermatology outpatient department of our hospital from March 2020 to February 2022. The dermoscopy images and pathological characteristics were analysed. RESULTS: Lesions were located on the hands, forearms and upper arms. The following dermoscopic features were observed: yellowish-orange structureless areas (85·2%), white striped structures (59·3%), follicular plugs (29·6%), yellowish oval clods (14·8%) and reddish or pinkish areas (14·8%). Vessel structures were visible in all cases: long hairpin vessels (81·5%), corkscrew vessels (25·9%), comma-shaped vessels (22·2%) and linear vessels (22·2%). CONCLUSION: Yellowish-orange structureless areas, white striped structures and long hairpin vessels are the most common dermoscopic features of M. marinum infection. Thus, dermoscopy could be used as a noninvasive auxiliary diagnostic method to provide a diagnostic basis for this disease.

Detection of skin thickness and density in healthy Chinese people by using high-frequency ultrasound.

OBJECTIVES: Due to a recent development of high-frequency ultrasound (HFUS) systems, it is easier to realize high-resolution in vivo imaging of the biological tissues. The object of this study was to map the thickness and echo density of skin layers in healthy Chinese people and assess the influence of gender, age, and region on it. METHODS: A total of 189 volunteers (85 male, 104 female) with age range of 22-75-year old (mean age of 41.2-year old) were enrolled. The thickness and density of the epidermis and dermis layer were detected by high-frequency (22 or 75 MHz) ultrasonography at 13 different anatomical sites, including the forehead, cheeks, flexor and extensor forearms, flexor and extensor upper arms, inner and outer legs, inner and outer thighs, back, and abdomen. RESULTS: The thickness and density of epidermis/dermis between different anatomical sites were statistically significant (p < 0.05). The epidermis thickness of the face and trunk were less than that of the limbs, whereas the thicknesses of the dermis were on the contrary. The density of the epidermis/dermis of the face and trunk were less than that of the limbs. The thickness of dermis in most of the sites were higher in male than in female, and the density of epidermis and dermis in most of the sites were less in men than in women. The thicknesses/densities of dermis were lower in older age group in almost all sites, whereas only several sites reached statistical. The difference between the north and south regions showed the environment also influenced the thickness and density of the skin. CONCLUSION: HFUS provides a simple noninvasive method for evaluating the skin thickness and echo-density, which, reflecting intradermal structure, exhibit systematic regional variation. With the establishment of Chinese phenotypic database of skin thickness and density, it will be helpful for the skin disease assessment, skin surgery, and cosmetology technology.

Summarization and comparison of dermoscopic features on different subtypes of rosacea.

BACKGROUND: The dermoscopic features of rosacea have already been reported. However, the current findings are incomplete, and little is known about phymatous rosacea. Hence, this study aimed to summarize and compare the dermoscopic features and patterns of three rosacea subtypes (erythematotelangiectatic [ETR], papulopustular [PPR], and phymatous [PHR]) in the Chinese Han population and to evaluate whether these features differ with patients' genders, ages, and durations. METHODS: Dermoscopic images of 87 rosacea patients were collected in non-polarized and polarized dermoscopy contact modes at 20-fold magnification. Dermoscopic features, including vessels, scales, follicular findings, and other structures, were summarized and evaluated. RESULTS: The reticular linear vessels and red diffuse structureless areas of ETR were distinctive. For PPR, red diffuse structureless areas, reticular linear vessels, yellow scales, follicular plugs, and follicular pustules were typical dermoscopic criteria. The common dermoscopic features of PHR were: orange diffuse structureless areas, linear vessels with branches, perifollicular white color, orange focal structureless areas, and white lines. The following features statistically differed among the three rosacea subtypes: reticular linear vessels ( P  < 0.001), unspecific linear vessels ( P  = 0.005), linear vessels with branches ( P  < 0.001), yellow scales ( P  = 0.001), follicular plugs ( P  < 0.001), perifollicular white color ( P  < 0.001), red diffuse structureless areas ( P  = 0.022), orange diffuse structureless areas ( P  < 0.001), red focal structureless areas ( P  = 0.002), orange focal structureless areas ( P  = 0.003), white lines ( P  < 0.001), follicular pustules ( P  < 0.001), and black vellus hairs ( P  < 0.001). CONCLUSIONS: The dermoscopic patterns of ETR are red diffuse structureless areas and reticular linear vessels. For PPR, the pattern comprehends combinations of red diffuse structureless areas, reticular linear vessels, yellow scales, follicular plugs, and follicular pustules. Meanwhile, PHR is characterized by remarkable orange diffuse structureless areas, linear vessels with branches, perifollicular white color, orange focal structureless areas, and white lines.

Inter-rater variability and consistency within four acne grading systems recommended in China, USA, and Europe.

PURPOSE: To investigate the correlation among different investigators (intrarater variation) in the assessment of acne vulgaris severity using Acne Grading System (AGS), International Improvement Grading System (IIGS), Investigator Global Assessment of acne (IGA), and Global Evaluation Acne (GEA), and to compare AGS and IIGS with the IGA recommended in the United States, and GEA in Europe. METHODS: A prospective cross-sectional study was conducted among patients with acne vulgaris, attending the dermatology outpatient clinics at five hospitals in China. Four investigators were engaged using AGS, IIGS, IGA, and GEA to assess severity of acne vulgaris. Correlation among AGS, IIGS, GEA, and IGA were analyzed. RESULTS: A total of 1107 participants suffering from acne vulgaris were enrolled. There was evidence of adequate internal consistency among AGS, IIGS, IGA, and GEA. For the intrarater reliability, AGS, IIGS, GEA, and IGA demonstrated excellent reliability. Moreover, AGS, IIGS, IGA, and GEA were significantly correlated with each other (p ≤ 0.01). CONCLUSION: IIGS and AGS were reliable, and correlated well with IGA and GEA.

Biological insights into systemic lupus erythematosus through an immune cell-specific transcriptome-wide association study.

OBJECTIVE: Genome-wide association studies (GWAS) have identified >100 risk loci for systemic lupus erythematosus (SLE), but the disease genes at most loci remain unclear, hampering translation of these genetic discoveries. We aimed to prioritise genes underlying the 110 SLE loci that were identified in the latest East Asian GWAS meta-analysis. METHODS: We built gene expression predictive models in blood B cells, CD4+ and CD8+ T cells, monocytes, natural killer cells and peripheral blood cells of 105 Japanese individuals. We performed a transcriptome-wide association study (TWAS) using data from the latest genome-wide association meta-analysis of 208 370 East Asians and searched for candidate genes using TWAS and three data-driven computational approaches. RESULTS: TWAS identified 171 genes for SLE (p<1.0×10-5); 114 (66.7%) showed significance only in a single cell type; 127 (74.3%) were in SLE GWAS loci. TWAS identified a strong association between CD83 and SLE (p<7.7×10-8). Meta-analysis of genetic associations in the existing 208 370 East Asian and additional 1498 cases and 3330 controls found a novel single-variant association at rs72836542 (OR=1.11, p=4.5×10-9) around CD83. For the 110 SLE loci, we identified 276 gene candidates, including 104 genes at recently-identified SLE novel loci. We demonstrated in vitro that putative causal variant rs61759532 exhibited an allele-specific regulatory effect on ACAP1, and that presence of the SLE risk allele decreased ACAP1 expression. CONCLUSIONS: Cell-level TWAS in six types of immune cells complemented SLE gene discovery and guided the identification of novel genetic associations. The gene findings shed biological insights into SLE genetic associations.

Comparison of dermoscopy and reflectance confocal microscopy accuracy for the diagnosis of psoriasis and lichen planus.

BACKGROUND: Dermoscopy and reflectance confocal microscopy (RCM) as noninvasive tools are gaining increasing importance in the diagnosis of inflammatory skin disorders. The purpose of our study was to calculate and compare the diagnostic accuracy of dermoscopy and RCM in common inflammatory skin diseases. MATERIALS AND METHODS: We retrospectively collected clinical, dermoscopic, and RCM images of psoriasis and lichen planuscases from March 2018 to February 2021 in China-Japan Friendship Hospital. There were 10 experts evaluated dermoscopic and RCM images independently. Sensitivity, specificity, positive predict value, and negative predictive value for each and all investigators were calculated. The diagnostic accuracy was also measured by the area under the curve (AUC) for the Receiver Operator Characteristic (ROC) Curves. RESULTS: We collected 82 psoriasis and 47 lichen planus cases. Dermoscopy was more sensitive than RCM in the diagnosis of psoriasis, and overall diagnostic accuracy of dermoscopy was also higher than RCM measured by AUC (0.879 vs. 0.835, p = 0.0001). For lichen planus, RCM had higher sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy than dermoscopy (AUC 0.916 vs. 0.813, p<0.0001). CONCLUSION: Dermoscopy and RCM play a significant role in assisting the diagnosis of psoriasis and lichens planus. These two noninvasive diagnostic tools have their own advantages and disadvantages for the evaluation of different inflammatory skin diseases, and they can be combined in clinical practice to improve the accuracy of the diagnosis of inflammatory skin diseases.

Deficiency of two-pore segment channel 2 contributes to systemic lupus erythematosus via regulation of apoptosis and cell cycle.

BACKGROUND: Systemic lupus erythematosus (SLE) is a complex autoimmune disease, and the mechanism of SLE is yet to be fully elucidated. The aim of this study was to explore the role of two-pore segment channel 2 (TPCN2) in SLE pathogenesis. METHODS: Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expression of TPCN2 in SLE. We performed a loss-of-function assay by lentiviral construct in Jurkat and THP-1 cell. Knockdown of TPCN2 were confirmed at the RNA level by qRT-PCR and protein level by Western blotting. Cell Count Kit-8 and flow cytometry were used to analyze the cell proliferation, apoptosis, and cell cycle of TPCN2-deficient cells. In addition, gene expression profile of TPCN2-deficient cells was analyzed by RNA sequencing (RNA-seq). RESULTS: TPCN2 knockdown with short hairpin RNA (shRNA)-mediated lentiviruses inhibited cell proliferation, and induced apoptosis and cell-cycle arrest of G2/M phase in both Jurkat and THP-1 cells. We analyzed the transcriptome of knockdown-TPCN2-Jurkat cells, and screened the differential genes, which were enriched for the G2/M checkpoint, complement, and interleukin-6-Janus kinase-signal transducer and activator of transcription pathways, as well as changes in levels of forkhead box O, phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin, and T cell receptor pathways; moreover, TPCN2 significantly influenced cellular processes and biological regulation. CONCLUSION: TPCN2 might be a potential protective factor against SLE.

Copy Number Variation Analysis of IL22 and LCE3C in Different Subtypes of Psoriasis in a Chinese Han Population.

BACKGROUND Psoriasis is a chronic, immune-mediated and hyperproliferative skin disease with both genetic and environmental components. Copy number variations (CNV) of IL22 and LCE3C-LCE3B deletion have been confirmed to be predisposed to psoriasis vulgaris (PsV) in several ethnic groups. However, it remains to be clarified whether CNVs of IL22 and LCE3C are associated with different subtypes of psoriasis (psoriatic arthritis, PsA; erythrodermic psoriasis, EP; and generalized pustular psoriasis, GPP). MATERIAL AND METHODS We enrolled 897 Han Chinese individuals, including 478 patients and 419 healthy controls, and detected CNVs of IL22 and LCE3C using the comparative CT method by real-time PCR, and Pearson's χ² test was used to evaluated the copy number difference among subtypes. RESULTS CNVs of IL22 were significantly higher in PsV than in healthy controls (P<0.001). CNV of LCE3C in PsV, PsA, and GPP groups were significantly lower compared to healthy controls. When linked with clinical parameters, mild psoriasis carried less IL22 copy numbers than that in severe psoriasis (P=0.043). Neither IL22 or LCE3C CNVs were associated with age of onset. CONCLUSIONS CNVs of LCE3C and IL22 might differentially contribute to subtypes of psoriasis. These findings suggest complex and diverse genetic variations in and among different clinical subtypes of psoriasis.

Dermoscopic Features Summarization and Comparison of Four Types of Cutaneous Vascular Anomalies.

Objective: Dermoscopic features of cutaneous vascular anomalies have been reported, but the described features currently known are limited and not well-understood. The aim of this study is to comprehensively summarize and compare the dermoscopic features of the four different types of cutaneous vascular anomalies [infantile hemangiomas (IH), cherry angioma (CA), angiokeratomas (AK), and pyogenic granuloma (PG)] in the Chinese Han population. Materials and Methods: Dermoscopic features of 31 IH, 172 CA, 31 AK, and 45 PG were collected based on the contact non-polarized mode of dermoscopy at 20-fold magnification. Dermoscopic features including background, lacunae, vessel morphology and distribution were collected and summarized. Additionally, we compared these features by age stage, gender, and anatomical locations in CA. Results: The dermoscopic features of IH included the red lacunae, red/red-blue/red-white backgrounds, and vessel morphology such as linear curved vessels, serpiginous vessels, coiled vessels. For CA, the lacunae appeared reddish brown to reddish blue or only red. In terms of vascular morphology, serpentine vessels, coiled vessels, looped vessels, and curved vessels could be seen in the lesions. A few lesions were black or presented with a superficial white veil. There were statistical differences in red background (P = 0.021), unspecific vessel distribution (P = 0.030), black area (P = 0.029), and white surface (P = 0.042) among different age groups. Red-brown lacunae (P = 0.039), red-blue (P = 0.013), red-white background (P = 0.015), black area (P = 0.016), and white surface (P = 0.046) were of statistical difference in terms of the locations of lesions. Lacunae were also observed in AK, which presented with red, dark purple, dark blue, black. Global dermoscopic patterns that were characterized by a homogeneous area were obvious in all PG lesions, among which 30 (66.7%) were red-white and 15 (33.3%) were red. As for local features, "white rail" lines were detected in 19 (42.2%) lesions and white collarette was seen in 34 (75.6%) lesions. Conclusions: Dermoscopy is an applicable diagnostic tool for the diagnosis of cutaneous vascular anomalies. It is necessary to take into account the age stage and lesion location when we diagnose CA using dermoscopy.

Skin diseases in the Da Qing Diabetes Study: a cross-sectional study.

BACKGROUND: The prevalence of skin diseases and diabetes mellitus (DM) are prominent around the world. The current scope of knowledge regarding the prevalence of skin diseases and comorbidities with type 2 DM (T2DM) is limited, leading to limited recognition of the correlations between skin diseases and T2DM. METHODS: We collected 383 subjects from the Da Qing Diabetes Study during the period from July 9th to September 1st, 2016. The subjects were categorized into three groups: Normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and T2DM. The prevalence and clinical characteristics of skin diseases were recorded and investigated. RESULTS: In this cross-sectional study, 383 individuals with ages ranging from 53 to 89-year-old were recruited. The overall prevalence of skin diseases was 93.5%, and 75.7% of individuals had two or more kinds of skin diseases. Additionally, there were 47 kinds of comorbid skin diseases in patients with T2DM, of which eight kinds of skin diseases had a prevalence >10%. The prevalence of skin diseases in NGT, IGT, and T2DM groups were 93.3%, 91.5%, and 96.6%, respectively; stratified analysis by categories showed a statistically significant difference in "disturbances of pigmentation" and "neurological and psychogenic dermatoses". The duration of T2DM also significantly associated with the prevalence of "disturbances of pigmentation" and "neurological and psychogenic dermatoses". Subsequently, the prevalence of "disturbances of pigmentation" was higher in males than females in NGT (P < 0.01) and T2DM (P < 0.01) groups. In addition, the difference in the prevalence of "disturbances of pigmentation" was also significant in NGT and T2DM groups (P < 0.01). CONCLUSIONS: There was a high prevalence of skin diseases in the Da Qing Diabetes Study. To address the skin diseases in the Da Qing Diabetes Study, increased awareness and intervention measures should be implemented.

Meta-analysis of 208370 East Asians identifies 113 susceptibility loci for systemic lupus erythematosus.

OBJECTIVE: Systemic lupus erythematosus (SLE), an autoimmune disorder, has been associated with nearly 100 susceptibility loci. Nevertheless, these loci only partially explain SLE heritability and their putative causal variants are rarely prioritised, which make challenging to elucidate disease biology. To detect new SLE loci and causal variants, we performed the largest genome-wide meta-analysis for SLE in East Asian populations. METHODS: We newly genotyped 10 029 SLE cases and 180 167 controls and subsequently meta-analysed them jointly with 3348 SLE cases and 14 826 controls from published studies in East Asians. We further applied a Bayesian statistical approach to localise the putative causal variants for SLE associations. RESULTS: We identified 113 genetic regions including 46 novel loci at genome-wide significance (p<5×10-8). Conditional analysis detected 233 association signals within these loci, which suggest widespread allelic heterogeneity. We detected genome-wide associations at six new missense variants. Bayesian statistical fine-mapping analysis prioritised the putative causal variants to a small set of variants (95% credible set size ≤10) for 28 association signals. We identified 110 putative causal variants with posterior probabilities ≥0.1 for 57 SLE loci, among which we prioritised 10 most likely putative causal variants (posterior probability ≥0.8). Linkage disequilibrium score regression detected genetic correlations for SLE with albumin/globulin ratio (rg=-0.242) and non-albumin protein (rg=0.238). CONCLUSION: This study reiterates the power of large-scale genome-wide meta-analysis for novel genetic discovery. These findings shed light on genetic and biological understandings of SLE.

Diagnostic capacity of skin tumor artificial intelligence-assisted decision-making software in real-world clinical settings.

BACKGROUND: Youzhi artificial intelligence (AI) software is the AI-assisted decision-making system for diagnosing skin tumors. The high diagnostic accuracy of Youzhi AI software was previously validated in specific datasets. The objective of this study was to compare the performance of diagnostic capacity between Youzhi AI software and dermatologists in real-world clinical settings. METHODS: A total of 106 patients who underwent skin tumor resection in the Dermatology Department of China-Japan Friendship Hospital from July 2017 to June 2019 and were confirmed as skin tumors by pathological biopsy were selected. Dermoscopy and clinical images of 106 patients were diagnosed by Youzhi AI software and dermatologists at different dermoscopy diagnostic levels. The primary outcome was to compare the diagnostic accuracy of the Youzhi AI software with that of dermatologists and that measured in the laboratory using specific data sets. The secondary results included the sensitivity, specificity, positive predictive value, negative predictive value, F-measure, and Matthews correlation coefficient of Youzhi AI software in the real-world. RESULTS: The diagnostic accuracy of Youzhi AI software in real-world clinical settings was lower than that of the laboratory data (P < 0.001). The output result of Youzhi AI software has good stability after several tests. Youzhi AI software diagnosed benign and malignant diseases by recognizing dermoscopic images and diagnosed disease types with higher diagnostic accuracy than by recognizing clinical images (P = 0.008, P = 0.016, respectively). Compared with dermatologists, Youzhi AI software was more accurate in the diagnosis of skin tumor types through the recognition of dermoscopic images (P = 0.01). By evaluating the diagnostic performance of dermatologists under different modes, the diagnostic accuracy of dermatologists in diagnosing disease types by matching dermoscopic and clinical images was significantly higher than that by identifying dermoscopic and clinical images in random sequence (P = 0.022). The diagnostic accuracy of dermatologists in the diagnosis of benign and malignant diseases by recognizing dermoscopic images was significantly higher than that by recognizing clinical images (P = 0.010). CONCLUSION: The diagnostic accuracy of Youzhi AI software for skin tumors in real-world clinical settings was not as high as that of using special data sets in the laboratory. However, there was no significant difference between the diagnostic capacity of Youzhi AI software and the average diagnostic capacity of dermatologists. It can provide assistant diagnostic decisions for dermatologists in the current state.

Profile of the skin microbiota in a healthy Chinese population.

The skin microbiota is an inseparable component of the skin barrier structure, which participates in the stabilization or impairment of the barrier function as well as the development of many skin diseases. To characterize the normal skin microbiota and its association with skin sites, age and sex, we recruited 50 volunteers divided into children, adolescents, young adults, middle-aged adults and the elderly. The skin sites consisted of cheeks, volar forearms (representing dry environments) and upper back (representing sebaceous environments). A total of 9 574 365 high-quality sequences of the V3 to V4 region of the 16S rRNA gene were annotated with taxonomic information related to two archaeal phyla (Thaumarchaeota and Euryarchaeota) and five dominant bacterial phyla (Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes and Cyanobacteria). The skin bacteria community structure was influenced by skin sites, and was closely related to age and sex. The upper back was dominated by Propionibacterium and Staphylococcus, and the cheeks facilitated the survival of Betaproteobacteria, while Alphaproteobacteria were prevalent on the volar forearms. Regarding the effects of age, after sexual maturity, the cheek microbiota became more similar to sebaceous sites (i.e. the upper back). The volar forearms appeared to experience the aging process earlier than the other two sites. The elderly had greater species richness and diversity and their community composition no longer had skin-site selectivity. Males had a greater species richness than females, but the sex differences in the community structure only present at certain age groups and skin sites.