Objective:To screen the Alzheimer's disease(AD)-related genes and construct its diagnostic model using bioinformatics technology and machine learning(ML)algorithms,to discuss the immunological characteristics of AD patients,and to provide novel biomarkers for AD diagnosis.Methods:The AD-related gene expression dataset GSE125583 was downloaded from the Gene Expression Omnibus(GEO)database.Differentially expressed genes(DEGs)were identified through differential analysis.Gene Ontology(GO)functional enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)signaling pathway enrichment analyses were performed to explore the biological functions and signaling pathways of DEGs.A protein-protein interaction(PPI)network was constructed,and hub genes were screened using Cytoscape software combined with three ML algorithms:Least Absolute Shrinkage and Selection Operator(LASSO),eXtreme Gradient Boosting(XGBoost),and Random Forest(RF).The screened hub genes were utilized to build an AD diagnostic model via RF,followed by feature importance ranking.The model's efficacy and key genes were evaluated using a test set.Single-sample gene set enrichment analysis(ssGSEA)was used for immune cell infiltration analysis between AD group and control group.Results:Differential analysis identified 1 287 DEGs.The GO functional enrichment analysis results revealed that DEGs were primarily involved in biological functions related to neural signaling,synapses,and vesicles.KEGG signaling pathway enrichment analysis indicated significant enrichment of DEGs in ion transport,neurotransmitter,and ligand-gated channel pathways.Nine overlapping hub genes were screened by the three ML algorithms.In the AD diagnostic model,the top four key genes with highest diagnostic performance were adenylate cyclase-activating polypeptide 1(ADCYAP1),brain-derived neurotrophic factor(BDNF),platelet-derived growth factor receptor β(PDGFRB),and C-X-C motif chemokine receptor 4(CXCR4),with corresponding area under the curve(AUC)values of 0.852,0.795,0.820,and 0.756,respectively.The model achieved an AUC of 0.828,accuracy of 81.25%,sensitivity of 84.40%,and specificity of 71.43%.The immune cell infiltration analysis results demonstrated higher infiltration of macrophages,monocytes,natural killer(NK)cells,and lymphocytes in AD tissue.Among these,NK/natural killer T(NKT)cells and plasmacytoid dendritic cells showed significant correlations with the four key genes(P<0.05).Conclusion:The feature genes screened based on bioinformatics and ML exhibit diagnostic potential for AD.Genes such as ADCYAP1 may serve as potential biomarkers for AD diagnosis,offering significant implications for early prevention and treatment.

ObjectiveTo investigate the effect of Glycyrrhizae Radix et Rhizoma （GR）-containing serum on lipopolysaccharide （LPS）-induced inflammation in human colon epithelial adenocarcinoma cells （Caco2） based on inhibition of ferroptosis by the nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） pathway. MethodCaco2 cells were divided into a normal group， a model group （LPS， 200 μg·L^-1）， low-， medium-， and high-dose GR-containing serum groups （5%， 10%， 20%）， and a ferroptosis inhibitor group （3-amino-4-cyclohexylamino-benzoic acid ethyl ester， Fer-1， 10 μmol·L^-1）. The cells in the normal group were cultured normally， while those in other groups underwent the induction of an inflammation model. The cells in the low-， medium-， and high-dose GR-containing serum groups were treated with 5%， 10%， and 20% GR-containing serum for 24 hours， respectively， and the cells in the ferroptosis inhibitor group were treated with Fer-1 for 24 hours. Transmission electron microscopy was used to observe mitochondrial morphology in each group. Flow cytometry was used to detect intracellular Fe²⁺ levels. Microplate assays were performed to measure superoxide dismutase （SOD） activity， malondialdehyde （MDA） and glutathione peroxidase （GSH-Px） levels. Enzyme-linked immunosorbent assay （ELISA） was used to measure interleukin-1β （IL-1β）， IL-6， IL-10， and tumor necrosis factor-α （TNF-α） levels. Western blot was used to measure the expression levels of Nrf2， HO-1， ferritin heavy chain 1 （FTH1）， and glutathione peroxidase 4 （GSH-Px4） proteins. Small interfering RNA （siRNA） was used to investigate the role of Nrf2 in ferroptosis regulation. The cells after interference were divided into a negative control （NC） group， a Si-Nrf2 group， a GR-containing serum （20%） + Si-Nrf2 group， and a GR-containing serum （20%） + NC group. Microplate assays were performed to measure MDA， SOD， and GSH-Px levels， and Western blot was used to measure the expression levels of Nrf2， HO-1， FTH1， and GSH-Px4 proteins. ResultCompared with the normal group， the model group showed mitochondrial contraction， increased mitochondrial membrane thickness， and smaller mitochondrial morphology， increased Fe²⁺ content （P<0.01）， blunted SOD activity （P<0.01）， decreased GSH-Px expression （P<0.01）， increased MDA content （P<0.01）， reduced expression levels of Nrf2 and HO-1 （P<0.05）， reduced FTH1 expression （P<0.01）， and down-regulated GSH-Px4 expression （P<0.01）. In the GR-containing serum groups， the medium- and high-dose groups showed a significant decrease in Fe²⁺ content （P<0.01）， potentiated SOD and GSH-Px activities （P<0.01）， and decreased MDA levels （P<0.01）. The high-dose group showed a significant increase in Nrf2 expression （P<0.05）， and the medium-dose group showed increased expression of HO-1 and GSH-Px4 proteins （P<0.05）. The expression levels of FTH1 significantly increased in the low-， medium-， and high-dose groups （P<0.01）. The study on mechanism revealed that compared with the NC group， the cells transfected with Nrf2 siRNA showed increased MDA content （P<0.01）， blunted SOD activity （P<0.01）， decreased GSH-Px activity （P<0.01）， decreased expression of Nrf2 and HO-1 （P<0.01）， and reduced levels of FTH1 and GSH-Px4 proteins （P<0.01）. Compared with the Si-Nrf2 group， the cells treated with GR-containing serum showed a decrease in MDA content （P<0.01）， an increase in SOD activity （P<0.01）， an increase in GSH-Px activity （P<0.01）， increased expression of Nrf2 and FTH1 proteins （P<0.05）， and higher expression levels of HO-1 and GSH-Px4 proteins （P<0.01）. ConclusionGR-containing serum can reduce the inflammatory cytokines and oxidative stress levels in LPS-induced Caco2 cells. Its mechanism is related to the promotion of Nrf2/HO-1 signaling pathway expression， alleviating intracellular lipid peroxidation and inhibiting ferroptosis.

Objective:To observe the clinical effect of acupuncture combined with Western medicine in the treatment of skin pruritus in maintenance hemodialysis patients.Methods:Eighty patients were randomly divided into a control group and an observation group,with 40 cases in each group.The control group was given loratadine orally,and the observation group was given acupuncture treatment in addition to the treatment used in the control group.The four-item itch questionnaire(FIIQ)score,indicators for skin barrier function,and serum interleukin(IL)-2 and IL-31 levels were compared.The efficacy was judged after the treatment ended.Results:The total effective rate was higher in the observation group than in the control group(P<0.05).After treatment,the site,frequency,severity of pruritus,sleep impact sub-scores,and FIIQ total score in both groups were reduced compared with those before treatment(P<0.05),and all scores in the observation group were lower than those in the control group(P<0.05).The stratum corneum hydration(SCH)and transepidermal water loss(TEWL)in the V-shaped area of the chest,the flexor side of the forearm,and the extensor side of the lower leg were not significantly changed in the control group(P>0.05);the SCH and TEWL in the V-shaped area of the chest,the flexor side of the forearm,and the extensor side of the lower leg in the observation group were improved(P<0.05),and all were better than those in the control group(P<0.05).The serum IL-2 and IL-31 levels in the control group did not change significantly(P>0.05);the serum IL-2 and IL-31 levels in the observation group were both significantly decreased(P<0.05)and were lower than those in the control group(P<0.05).Conclusion:Acupuncture combined with loratadine is highly effective in the treatment of pruritus in maintenance hemodialysis patients,and it can relieve pruritus,improve skin barrier function,and reduce serum IL-2 and IL-31 levels.