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Concentrically zoned pyrite aggregates (CZPA) are common in sediment‐hosted massive sulfide (SHMS) deposits and have been widely used to interpret the ore‐forming processes. There is considerable uncertainty, however, over the formation of aggregates that are oscillatorily zoned and contain randomly‐orientated pyrite microcrystals. Guided by the results of examination of the micro‐textures of CZPA and in‐situ chemical analyses, we conducted a quantitative diffusion‐reaction simulation to assess the mechanism of CZPA formation. Our study shows that oscillatory zoning results from the feedback between the diffusion of reactants and the nucleation‐growth of Fe‐sulfides. Externally derived Fe2+ diffuses into the early diagenetic sediments containing decomposing organic matter (2CH2O + SO42− = 2HCO3− + H2S) and reacts with H2S to form a pyrite layer via an intermediate pathway (Fe2+ + H2S → FeS + 2H+, FeS + H2S → FeS2 + H2). This growth of pyrite layers depletes the local concentration of reactants and suppresses nucleation until the diffusive reaction front advances and another layer is formed. Intermediate phases, for example, mackinawite, nucleate instead of pyrite, because of their greater ease of nucleation due to the low surface tension, and lead to the domination of nucleation over growth. The nucleation of mackinawite and occurrence of siderite in the CZPA are consistent with a low temperature, high pH, anoxic early diagenetic environment. Our study demonstrates that CZPA in SHMS deposits are formed by intrinsic self‐organizational processes rather than by extrinsic changes of ore‐forming fluids. The CZPA in SHMS deposits are thus indicative of their diagenetic origin with Fe2+ infiltrated and diffused from hydrothermal fluids into the sediments. Plain Language Summary: Oscillatory zoning patterns are a phenomenon commonly encountered in scientific disciplines that include biology, geology, chemistry and atmospheric physics. To decipher these patterns, we employ a unifying principle that leverages a reaction‐diffusion approach and successfully replicate the textures observed in a massive sulfide deposit, via numerical simulations. In addition, we show that factors such as the concentration, distribution, and mobility of reactant species, such as the iron ion, sulfide, and organic matter in sediments, influence the texture of patterns at both the millimeter and nanometer scales. Our proposed numerical models yield results that closely align with the oscillatory zoning patterns observed in pyrite‐siderite from the Xinqiao massive sulfide deposit in Central China. The broader impact of this work lies in the development of a computer simulation‐based protocol, which sheds light on the processes forming massive sulfide deposits. This, in turn, has the potential to significantly aid the exploration for new metal and sulfide resources beneath the surface of the Earth. Key Points: Reactive‐diffusion simulations of the formation of concentrically zoned pyrite aggregates in sediment‐hosted massive sulfide depositsThe ore textures were the result of an intrinsic self‐organized process rather than extrinsic changes of chemical compositionsProtocols for deciphering diagenetic environments affected by the infiltration of Fe2+‐rich hydrothermal fluids [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is a common inflammatory skin condition and the leading cause of morbidity associated with skin conditions worldwide. For the majority of patients, AD is a lifelong disease that cannot be cured completely. Therefore, in the present study, differentially expressed genes (DEGs) in the epidermal immune microenvironment were screened using bioinformatic techniques. Subsequently, an in vitro cellular model was constructed to investigate the role of microRNA (miR)-155 in immune infiltration during AD. In the present study, two datasets (GSE121212 and GSE157194) were downloaded from Gene Expression Omnibus, before the DEGs were screened and subjected to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functional enrichment analyses. miRNet was used to predict the possible target genes of miR-155 among the differentially expressed genes found. Consequently, peptidase inhibitor 3 (PI3), FOS-like 1, AP-1 transcription factor subunit (FOSL1), C-X-C motif chemokine ligand (CXCL)1 and CXCL8 were selected to be the potential target genes of miR-155 in the epidermal immune microenvironment of patients with AD. Concurrently, an inflammatory cell model using HaCaT cells was constructed by TNF-α and IFN-γ treatment. The effects of miR-155 on HaCaT cell proliferation and secretion of IL-1β, IL-6, IL-10, IL-15, PI3, FOSL1, CXCL1 and CXCL8 under inflammatory and non-inflammatory conditions were then analyzed. The results showed that after the HaCaT cells were transfected with miR-155, miR-155 inhibited HaCaT cell proliferation and decreased the mRNA expression levels of PI3 and CXCL8, increased the mRNA levels of FOSL1 and secretion levels of IL-1β, IL-6, IL-15 and CXCL1. By contrast, miR-155 decreased the secretion levels of IL-10 and CXCL8. In the inflammatory cell model of HaCaT cells, miR-155 was found to significantly inhibit the proliferation of HaCaT cells during inflammation whilst significantly increasing the secretion of IL-1β, IL-6, IL-10 and IL-15. In addition, miR-155 increased the mRNA expression and secretion levels of CXCL1 and CXCL8, whilst also increasing the mRNA expression levels of PI3. Results from the current study suggest that miR-155 can stimulate keratinocytes to produce inflammatory cytokines and proteins to enhance the inflammatory response in AD. [ABSTRACT FROM AUTHOR]

Psoriasis (PS) is a chronic inflammatory skin disease with a long course and tendency to recur, the pathogenesis of which is not fully understood. This article aims to identify the key differentially expressed genes (DEGs) and microRNA (miRNAs) of PS, construct the core miRNA-mRNA regulatory network, and investigate the underlying molecular mechanism through integrated bioinformatics approaches. Two gene expression profile datasets and 2 miRNA expression profile datasets were downloaded from the gene expression omnibus (GEO) database and analyzed by GEO2R. Intersection DEGs and intersection differentially expressed miRNAs (DEMs) were each screened. The Metascape database and R software were used to perform enrichment analysis of intersecting DEGs and study their functions. Target genes of DEMs were predicted from the online database miRNet. The protein-protein interaction files of the overlapping target genes were obtained from string and the miRNA-mRNA network was constructed by Cytoscape software. In addition, the online web tool CIBERSORT was used to analyze the immune infiltration of dataset GSE166388, and the relative abundance of 22 immune cells in the diseased and normal control tissues was calculated and assessed. Finally, quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to verify the relative expression of the screened miRNAs and mRNAs to assess the applicability of DEMs and DEGs as biomarkers in PS. A total of 205 mating DEGs and 6 mating DEMs were screened. 103 dysregulated crossover genes from 205 crossover DEGs and 7878 miRNA target genes were identified. The miRNA-mRNA regulatory network was constructed and the top 10 elements were obtained from CytoHubba, including hsa-miR-146a-5p, hsa-miR-17-5p, hsa-miR-106a-5p, hsa-miR-18a-5p, CDK1, CCNA2, CCNB1, MAD2L1, RRM2, and CCNB2. QRT-PCR revealed significant differences in miRNA and gene expression between inflammatory and normal states. In this study, the miRNA-mRNA core regulator pairs hsa-miR-146a-5p, hsa-miR-17-5p, hsa-miR-106a-5p, hsa-miR-18a-5p, CDK1, CCNA2, CCNB1, MAD2L1, RRM2, and CCNB2 may be involved in the course of PS. This study provides new insights to discover new potential targets and biomarkers to further investigate the molecular mechanism of PS., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)