Hypoxemia is a common pathological state characterized by low oxygen saturation in the blood. This condition compromises mucosal barrier integrity particularly in the gut and oral cavity. However, the mechanisms underlying this association remain unclear. This study used periodontitis as a model to investigate the role of platelet activation in oral mucosal immunopathology under hypoxic conditions. Hypoxia upregulated methyltransferase-like protein 4 (METTL4) expression in platelets, resulting in N⁶-methyladenine modification of mitochondrial DNA (mtDNA). This modification impaired mitochondrial transcriptional factor A-dependent cytosolic mtDNA degradation, leading to cytosolic mtDNA accumulation. Excess cytosolic mt-DNA aberrantly activated the cGAS-STING pathway in platelets. This resulted in excessive platelet activation and neutrophil extracellular trap formation that ultimately exacerbated periodontitis. Targeting platelet METTL4 and its downstream pathways offers a potential strategy for managing oral mucosa immunopathology. Further research is needed to examine its broader implications for mucosal inflammation under hypoxic conditions.
DNA, Mitochondrial/metabolism* ; Mouth Mucosa/pathology* ; Hypoxia/immunology* ; Methyltransferases/metabolism* ; Blood Platelets/metabolism* ; Animals ; Periodontitis/immunology* ; Humans ; Platelet Activation ; Mice

Tinnitus refers to the perception of abnormal sound in the absence of external sound stimulation. It can have an impact on a person's mood, memory, attention, and mental state, although the mechanism of tinnitus is still unclear. In recent years, the research on the central neural mechanism of tinnitus has attracted the attention of scholars.Functional magnetic resonance imaging （fMRI）,as an effective imaging technology, has been actively employed in this field. This paper provides a systematic summary of studies on the central neural mechanism of tinnitus by fMRI in recent years,revealed the changes of functional connections among tinnitus-related neural networks,such as auditory network,limbic system,default mode network and salience network. The central neural mechanism of tinnitus involves multiple networks that interact with each other. By understanding this mechanism, we hope to develop more targeted prevention and treatment strategies to help patients alleviate long-term tinnitus.
Humans ; Tinnitus/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Attention

Objective To investigate whether gut microbiome dysbiosis and translocation occurred in experimental uremia,and whether they consequently contribute to microinflammation.Methods Health male SD rats were randomly divided into uremic group and sham group.Uremic group were operated for 5/6 nephrectomy to establish uremic models,while sham group were only operated for nephrocapsulotomy.Postoperative blood,livers,spleens,and mesenteric lymph nodes (MLNs) were subjected to bacterial 16S ribosomal DNA amplification to determine if bacteria were present.Bacterial genomic DNA samples from the MLNs and colon were amplified with specific primers designed by the 16SrRNA sequence of the species obtained from blood,livers and spleens.Pyrosequencing was used to analyze the ileum and colonic microbio.me of each subject.Intestinal permeability to 99mTc-DTPA,plasma hs-CRP,and IL-6 were measured.Results Bacterial DNA in extraiutestinal sites and altered colonic microbiomes at the phylum,family,and genus levels were detected in some rats in the uremic group.Bacterial genomic DNA in MLNs and colon were obtained by primers specific for bacterial species observed from blood,livers,and spleens of identical individuals.Intestinal permeability,plasma hs-CRP,and IL-6 levels were statistically higher in the uremic group compared with that in sham group(all P ＜ 0.05).Conclusion Gut microbiome dysbiosis occurs and presumably bacteria translocate to the systemic and lymph circulation,thereby contributing to microinflammation in experimental uremia.