Objective:To investigate relationships between nasal parasitism by Demodex mites and nasal skin microbiome in patients with rosacea. Methods:From May 2017 to June 2019, 14 patients with rosacea, including 8 with early-stage rosacea and 6 with intermediate-stage rosacea, and 14 human controls with healthy facial skin were collected from Department of Dermatology, Shunde District Center for Prevention and Cure of Chronic Disease of Foshan City. Microbial samples were collected from the nasal alar and nasolabial folds of the subjects. Then, DNA was extracted from the samples, and subjected to metagenomic sequencing and bioinformatics analysis. Relative abundance of strains was estimated by using composition ratios of Demodex mites and microbial reads. Shannon index was calculated to evaluate α diversity of microbiome, and principal component analysis (PCA) was performed to assess β diversity based on relative abundance of microbial species. Enumeration data were compared by using two-independent-sample t test, and relationships between nasal Demodex mites and skin microbiome were analyzed by Pearson correlation analysis. Results:The relative abundance of nasal Demodex mites was significantly higher in the rosacea group (1.647% ± 0.389%) than in the healthy group (0.448% ± 0.089%, t = 2.92, P = 0.007) . The relative abundance of Demodex mites was negatively correlated with the relative abundance of bacteria ( r = -0.95, P < 0.001) , and positively correlated with the relative abundance of fungi ( r = 0.76, P < 0.001) . The Shannon indices of nasal bacterial and fungal communities were significantly higher in the rosacea group (0.91 ± 0.17, 1.261 ± 0.045, respectively) than in the healthy group (0.47 ± 0.12, 0.549 ± 0.071, t = 2.17, 8.48, respectively, both P < 0.05) ; PCA showed that the β diversity of bacterial communities significantly differed between the rosacea group and healthy group ( t = 2.32, P = 0.029) , while no significant difference in the β diversity of fungal communities was observed between the two groups ( t = 0.82, P = 0.461) . In addition, the relative abundance of Demodex mites was significantly higher in the patients with intermediate-stage rosacea than in those with early-stage rosacea ( t = 6.56, P < 0.001) ; there was no significant difference in the Shannon indices of nasal bacterial or fungal communities between the two patient groups (both P > 0.05) ; PCA showed that the β diversities of bacterial and fungal communities significantly differed between the two patient groups (both P < 0.05) . Conclusion:Parasitism of Demodex mites on the nasal skin may affect nasal microbial community structure.

OBJECTIVEPsoriasis is an autoimmune-related chronic inflammatory skin disease strongly associated with the dysfunction of Th17 cells. Retinoic acid-related orphan nuclear receptor γt (RORγt) plays a critical role in the differentiation and maturation of Th17 cells and in cell-derived immunologic derangement. We conducted this study to investigate potential mechanism by which the derivative of digoxin selectively antagonizes RORγt transcriptional activity.

METHODUsing molecular docking in combination with molecular electrostatic potential (MEP), we detected the interaction between the derivative of digoxin (Dhd) and ROR transcription factor (RORα,RORβ and RORγt), and the results were further confirmed by bioluminescent assay.

RESULTMolecular docking demonstrated that Dhd could exclusively inhibit the conformation of RORγt; bioluminescent assay further indicated that RORγt was selectively antagonized by Dhd in a dose- and time-dependent manner.

CONCLUSIONDhd can selectively suppress RORγt transcriptional activity.

Digoxin ; analogs & derivatives ; pharmacology ; Humans ; Models, Chemical ; Molecular Docking Simulation ; Nuclear Receptor Subfamily 1, Group F, Member 1 ; antagonists & inhibitors ; genetics ; Transcription, Genetic

Objective: To evaluate the effect of age and gender on skin microbiome on the face of healthy adults by metagenomic sequencing. Methods: From June 2017 to June 2018, 36 adult volunteers with healthy facial skin were enrolled from the Department of Dermatology, Center for Prevention and Treatment of Chronic Diseases of Shunde, including 16 young volunteers (9 males and 7 females) aged 24-31 (27.1 ± 1.3) years and 20 senior volunteers (10 males and 10 females) aged 61-84 (75.8 ± 2.2) years. Skin microbe samples were obtained from the cheek of volunteers, and DNA was extracted from these samples and subjected to metagenomic sequencing and bioinformatic analysis, so as to evaluate the effect of age and gender factors on microbiota on the healthy facial skin of adults. Statistical analysis was carried out by using two independent-sample t test, Wilcoxon rank sum test and Pearson correlation analysis. Results: The senior group showed significantly higher α diversities of bacterial and fungal communities on the facial skin (Shannon index: 0.98 ± 0.07, 1.11 ± 0.05 respectively) compared with those in the young group (0.72 ± 0.09, 0.81 ± 0.05 respectively; t = 2.201, 3.836, P = 0.035, < 0.001 respectively) . Principal component analysis revealed that age could significantly affect β diversities of bacterial and fungal communities on the facial skin (t = 6.991, 11.591 respectively, both P < 0.001) . There were no significant differences in α diversities of bacterial and fungal communities between males and females (Shannon index: bacteria, 0.83 ± 0.08 vs. 0.92 ± 0.09; fungi, 0.92 ± 0.06 vs. 1.04 ± 0.05; t = 0.801, 1.332 respectively, both P > 0.05) . Gender factor could only affect the β diversity of bacterial communities (t = 2.149, P = 0.020) , but not the β diversity of fungal communities (t = 0.439, P = 0.663) . Moreover, the activity of metabolic pathways in bacterial and fungal communities was significantly lower in the senior group than in the young group (t = 1.995, 2.464, P = 0.020, 0.025, respectively) , while gender factor did not affect the activity of metabolic pathways in bacterial and fungal communities (t = 0.895, 0.483, P = 0.378, 0.631, respectively) . According to the relative abundance of different bacteria and fungi between the senior group and young group, Pearson correlation analysis showed positive or negative correlations between some fungi and bacteria, between some bacteria and bacteria, as well as between some fungi and fungi. Conclusion Age factor, but not gender, markedly affects α and β diversities of, and activity of metabolic pathways in bacterial and fungal communities on the healthy face of adults.