A growing interest in the comprehensive pathogenic mechanisms of psychiatric disorders from the perspective of the microbiome has been witnessed in recent decades; the intrinsic link between microbiota and brain function through the microbiota-gut-brain axis or other pathways has gradually been realized. However, little research has focused on viruses-entities characterized by smaller dimensions, simpler structures, greater diversity, and more intricate interactions with their surrounding milieu compared to bacteria. To date, alterations in several populations of bacteriophages and viruses have been documented in both mouse models and patients with psychiatric disorders, including schizophrenia, major depressive disorder, autism spectrum disorder, and Alzheimer's disease, accompanied by metabolic disruptions that may directly or indirectly impact brain function. In addition, eukaryotic virus infection-mediated brain dysfunction provides insights into the psychiatric pathology involving viruses. Efforts towards virus-based diagnostic and therapeutic approaches have primarily been documented. However, limitations due to the lack of large-scale cohort studies, reliability, clinical applicability, and the unclear role of viruses in microbiota interactions pose a challenge for future studies. Nevertheless, it is conceivable that investigations into viruses herald a new era in the field of precise psychiatry.
Humans ; Mental Disorders/virology* ; Animals ; Brain/virology* ; Gastrointestinal Microbiome/physiology* ; Viruses ; Virus Diseases/complications*

Objective:To investigate the effect of KRT5 knockdown in keratinocytes on melanin content in co-cultured melanocytes, and to explain mechanisms underlying formation of hyperpigmented lesions in reticulate pigmented anomaly of the flexures (Dowling-Degos disease, DDD) .Methods:HaCaT cells with heterozygous mutations in the KRT5 gene were obtained by using clustered regularly interspaced short palindromic repeats (CRISPR) -CRISPR-associated protein 9 (Cas9) technology (experimental group) , and HaCaT cells transfected with non-targeting single guide RNA:Cas9 protein complex served as control group, both of which were in vitro co-cultured with primary human melanocyte cells (HEMn) separately. Immunofluorescence study was conducted to determine the expression of cytokeratin and melanosomes in co-cultured cells; melanin content was detected in melanocytes in different co-culture groups, which were obtained by differential trypsinization. Immunohistochemical study was performed to determine the expression of melanocyte-specific premelanosome protein 17 (Pmel17) in skin lesions in a patient with DDD carrying a KRT5 mutation and normal skin tissues in a healthy control. Results:Sanger sequencing showed a heterozygous mutation (c.1delA) at the initiation codon of exon 1 of the KRT5 gene in HaCaT cells in the experimental group, but no mutation in the KRT5 gene in the control group. Western blot analysis showed that the KRT5 protein expression was significantly lower in the experimental group (0.60 ± 0.05) than in the control group (1.00 ± 0.00, t = 32.38, P = 0.001) . Compared with the co-culture system in the control group, the number of Pmel17-labeled melanosomes markedly increased with the melanin content elevated by 52.5% ( t = -3.48, P = 0.025) in the HEMn cells co-cultured with HaCaT cells in the experimental group. Immunohistochemical study showed that the Pmel17 expression increased in the skin lesions in the DDD patient with KRT5 mutation compared with the normal skin tissues in the healthy control. Conclusion:The effect of HaCaT cells with CRISPR-Cas9-induced KRT5 mutation on the co-cultured HEMn melanocytes was verified by the successfully established in vitro co-culture system, which provides a primary cell model for further studies on interaction mechanisms between keratinocytes and melanocytes, and on pathogenesis of skin pigmentation abnormalities.

In order to develop a method to more accurately determine the surgical boundary of extramammary Paget′s disease, reflectance confocal microscopy was used to determine the tumor boundary followed by modified extended excision in 2 cases of pathologically diagnosed extramammary Paget′s disease of the vulva. No residual tumor was observed in the resection margins by postoperative pathological examination at 4 positions (12, 3, 6 and 9 o′clock) , and follow-up showed no recurrence 1 year later.