BACKGROUND:In recent years,with the rapid development of biomedicine,the study of brain aging and exosomes has attracted more and more attention,but there is no bibliometrics analysis in this field. OBJECTIVE:To objectively analyze domestic and foreign literature on brain aging and exosomes in the past 15 years,to summarize the research status,hot spots,and development trends in this field. METHODS:Using the core database of Web of Science as a search platform,we downloaded the literature on brain aging and exosomes published from the establishment of the database to December 28,2022,and analyzed the data from the aspects of country or region,institution,author,keywords,and co-cited literature using CiteSpace 6.1.R6 visualization software. RESULTS AND CONCLUSION:A total of 1 045 research articles were included,and the number of publications on brain aging and exosomes research both domestically and internationally was showing an increasing trend year by year.The United States ranked first with 429 papers,and China ranked second with 277 papers.Louisiana State University ranked first with 16 articles.Professor Lukiw Walter J from Louisiana State University in the United States was the author with the highest number of publications,and Professor Bartel DP from the Massachusetts Institute of Technology was the author with the most citations.The most prolific Journal was the International Journal of Molecular Sciences.Alzheimer's disease,microRNA,gene expression,extracellular vesicles,exosomes,oxidative stress,and biomarkers are the most relevant terms.According to the research on hot topics,biomarkers have become a new research hotspot.The above results indicate that the research on brain aging and exosomes has gradually increased in the past 15 years.The research direction has gradually shifted from the initial exploration of the expression of miRNAs in central nervous system diseases related to brain aging to the search for biomarkers that can identify and diagnose neurodegenerative diseases.The study of exocrine miRNAs to protect central nervous system from damage has emerged as promising therapeutic strategy.

Objective To explore the epidemic characteristics of common pneumonia pathogens in preschool children in Xining area and analyze the influencing factors of progression to severe pneumonia. Methods A total of 522 preschool children with pneumonia who were treated in our hospital from May 2021 to March 2024 were retrospectively selected as the research subjects. Sputum samples from children were taken to identify the pathogens and analyze their pathogenic epidemic characteristics.According to the diagnostic criteria in the 2019 version of ^“Standards for the Diagnosis and Treatment of Community-Acquired Pneumonia in Children^”, determine whether it is severe pneumonia, and collect the clinical data of the children.Logistic regression was used to analyze the influencing factors of the progression of common pneumonia to severe pneumonia. Results Among the 522 children with pneumonia, 522 cases were infected with pathogens, of which 447 cases were single infection (85.63%), 75 cases were mixed infection (14.36%). A total of 597 pathogens were detected, including 257 viruses (43.05%), 240 bacteria (40.20%), 68 mycoplasma pneumoniae (11.39%) and 32 chlamydia pneumoniae (5.36) . The detection rates of Streptococcus pneumoniae (149, 24.96%) and respiratory syncytial virus (118, 19.77%) were higher. Logistic regression results showed that length of hospital stay (OR=2.235, 95% CI: 1.552-3.439), ICU admission (OR=2.426, 95% CI: 1.769-3.881), intestinal microbiota disorder (OR=1.626, 95% CI: 1.335-2.842), multi-drug resistance (OR=2.086, 95%CI 1.417-2.905), mixed infection (OR=3.134, 95% CI : 2.217-8.857), nutritional risk (OR=2.783, 95% CI: 2.038-4.764), CRP (OR=2.589, 95% CI: 1.805-4.117), PCT (OR=1.486, 95%CI: 1.077-1.649), and white blood cells (OR=1.329, 95% CI: 1.021-1.536) were all associated with the risk of severe pneumonia (P<0.05). Conclusion The main pathogens of pneumonia in preschool children in Xining are Streptococcus pneumoniae and respiratory syncytial virus. Paying attention to the treatment of children with intestinal disorders, multiple infections, and malnutrition is of great significance to improve the progression of pneumonia.

Objective To retrospectively analyze the efficacy and safety of low-dose antithymocyte globulin(ATG)combined with low-dose post transplantation cyclophosphamide(PTCY)in prevention of graft versus host disease(GVHD)after haploidentical transplantation.Methods Clinical data of 90 patients receiving haplotype matched transplantation in No.920 Hospital of PLA Joint Logistic Support Force from January 2022 to February 2023 were collected,and they were divided into study group(n=47)and control group(n=43)according to different GVHD prevention programs.The patients of the study group were given low-dose ATG combined with low-dose PTCY,and those of the control group received standard dose of PTCY.The implantation status,occurrence of GVHD,survival status and other indicators were analyzed between the 2 groups.Results ① Both groups of patients were successfully implanted,the median duration for neutrophil implantation(11 vs 17 d,P＜0.05)and platelet implantation(12 vs 20 d,P＜0.05)was significantly shorter in the study group than the control group.The incidence of grade Ⅱ～Ⅳ aGVHD(12.8％vs 34.9％,P＜0.05)and grade Ⅲ～Ⅳ aGVHD(6.4％ vs 20.9％,P＜0.05)was significantly lower in the study group than the control group,so was the non-recurrent mortality rate(6.4％vs 20.9％,P＜0.05)and the incidence of hemorrhagic cystitis(12.8％ vs 34.9％,P＜0.05).② By the end of the study,there were no significant differences in the incidence of mild and moderate and severe cGVHD,recurrence rate,reactivation rates of EBV and CMV,overall survival rate or progression-free survival rate between the 2 groups.Conclusion For haploidentical transplantation,low-dose ATG combined with low-dose PTCY has the advantages of lower incidence of GVHD,non-recurrent mortality,incidence of hemorrhagic cystitis and faster implantation.

Objective:To explore the expression of connexin 43 (Cx43) in hippocampus of post-stroke depression (PSD) model rats and its effect on cell apoptosis and depressive-like behavior.Methods:Sixty SPF-grade male SD rats aged 6-8 weeks were randomly divided into five groups (12 rats in each group): normal group, stroke group, depression group, PSD group and carbenoxolone(CBX) group. The stroke model was established by injection of endothelin-1.Chronic unpredictable mild stress (CUMS) combined with solitary rearing was used to establish a depression model. Rats in PSD group were given CUMS and raised alone on the seventh day of stroke modeling.Rats in CBX group were given intraperitoneal injection of CBX(20 mg/kg) on 14th day after PSD modeling. The depressive-like behavior of rats was evaluated by sugar water preference test and open field test. The expression of Cx43 mRNA in hippocampus of rats was detected by RT-PCR, the expression levels of Cx43, caspase-3, Bax and Bcl-2 were detected by Western blot, and the changes of apoptosis rate were detected by TUNEL staining. SPSS 23.0 software was used for statistical analysis, the behavioral data were analyzed by repeated measurement ANOVA, the remaining data were analyzed by one-way ANOVA, and the LSD- t test was used for further pairwise comparison. Results:(1)As for the preference rate of sugar water and the times of crossing the grid, the interaction effects between time and group were significant among the 5 groups( Finteraction=35.57, 111.43, both P<0.05). On the 28th day after operation, the preference rate of sugar water and the times of crossing grid in depression group and PSD group were lower than those in stroke group (all P<0.05), while the preference rate of sugar water and the times of crossing grid in CBX group were both lower than those in PSD group (both P<0.05). (2) The levels of Cx43 mRNA and Cx43 protein in the five groups were significantly different ( F=273.57, 64.56, both P<0.05). The levels of Cx43 mRNA and Cx43 protein in depression group ((0.59±0.05), (0.69±0.08)) and PSD group ((0.61±0.07), (0.63±0.12)) were lower than those in stroke group ((1.01±0.03), (1.05±0.08)) (all P<0.05). The levels of Cx43 mRNA and Cx43 protein in CBX group ((0.30±0.01), (0.37±0.09)) were lower than those in PSD group (both P<0.05). (3) The protein levels of caspase-3, Bax, Bcl-2 and Bcl-2/Bax and the apoptosis rate of the five groups were significantly different ( F=102.40, 90.27, 47.42, 159.99, 115.21, all P<0.05). The levels of caspase-3, Bax protein, apoptosis rate in stroke group ((0.44±0.06), (0.54±0.07), (29.16±5.03)) and depression group ((0.45±0.07), (0.59±0.09), (27.00±4.93)) were higher than those in normal group ((0.21±0.08), (0.33±0.07), (4.83±3.18)) (all P<0.05), the levels of Bcl-2 protein and Bcl-2/Bax in stroke group ((0.80±0.04), (1.51±0.20)) and depression group ((0.60±0.09), (1.03±0.09)) were lower than those in normal group ((1.04±0.13), (3.14±0.38)) (all P<0.05).The levels of caspase-3, Bax protein and apoptosis rate in PSD group ((0.76±0.05), (0.84±0.02), (44.50±3.83)) were all higher than those in stroke group and depression group (all P<0.05), and the levels of Bcl-2 protein and Bcl-2/Bax in PSD group ((0.50±0.14), (0.59±0.17)) were lower than those in stroke group and depression group (both P<0.05). The levels of caspase-3 and Bax protein and the apoptosis rate in CBX group ((1.03±0.10), (1.02±0.05), (56.00±4.81)) were higher than those in PSD group (all P<0.05).The levels of Bcl-2 protein and Bcl-2/Bax in CBX group((0.26±0.08), (0.25±0.08)) were lower than those in PSD group (both P<0.05). Conclusion:The expression level of Cx43 in the hippocampus of PSD model rats is downregulated, which can promote cell apoptosis and exacerbate depressive behavior.

Objective To analyze the expression of microRNA-451 (miR-451) in children with microcytic anemia and chronic infectious anemia, and to explore the correlation between miR-451 and erythrocyte-related parameters and its diagnostic value for anemia in children. Methods The expression levels of miR-451 in serum were detected in children with microcytic anemia (n=80), chronic infectious anemia (n=80), and healthy controls (n=80) using real-time fluorescence quantitative polymerase chain reaction (qRT-PCR). The correlation between serum miR-451 and erythrocyte-related parameters[red blood cell distribution width (RDW), red blood cells (RBC), mean corpuscular hemoglobin concentration (MCHC), hemoglobin (Hb), mean corpuscular hemoglobin content (MCH), mean corpuscular volume (MCV)]was analyzed using Pearson correlation analysis. The receiver operating characteristic (ROC) curve was plotted to analyze the diagnostic value of miR-451 for microcytic anemia, chronic infectious anemia, and the severity of anemia. Multivariate Logistic regression analysis was used to investigate the influencing factors for the occurrence of microcytic anemia and chronic infectious anemia in children. Results The expression levels of serum miR-451 in the microcytic anemia group and chronic infectious anemia group were lower than those in the healthy control group(P < 0.05). The miR-451 was negatively correlated with RDW (r=-0.388, P < 0.05), and positively correlated with Hb, RBC, MCHC, MCH, and MCV (r=0.402, 0.393, 0.391, 0.360, 0.323, P < 0.05). ROC curve analysis showed that the areas under the curve of serum miR-451 for diagnosing microcytic anemia and chronic infectious anemia was 0.718 and 0.735, respectively, which was higher than that of erythrocyte-related parameters such as RDW, Hb, RBC, MCHC, MCH, and MCV (P < 0.05). Multivariate Logistic regression analysis showed that body mass index, RDW, Hb, RBC, MCHC, MCH, MCV, and miR-451 were influencing factors for the occurrence of microcytic anemia and chronic infectious anemia in children (P < 0.05). With the aggravation of anemia in children, the expression level of serum miR-451 gradually decreased (P < 0.05). ROC curve analysis showed that the level of serum miR-451 had a high diagnostic value for the severity of anemia in children. Conclusion The expression of miR-451 is reduced in serum of children with microcytic anemia and chronic infectious anemia, and its expression level is correlated with erythrocyte-related parameter levels. Serum miR-451 has a high diagnostic value for microcytic anemia, chronic infectious anemia, and the severity of anemia.

Pulmonary fibrosis (PF) is the pathological structure of incurable fibroproliferative lung diseases that are attributed to the repeated lung injury-caused failure of lung alveolar regeneration (LAR). Here, we report that repetitive lung damage results in a progressive accumulation of the transcriptional repressor SLUG in alveolar epithelial type II cells (AEC2s). The abnormal increased SLUG inhibits AEC2s from self-renewal and differentiation into alveolar epithelial type I cells (AEC1s). We found that the elevated SLUG represses the expression of the phosphate transporter SLC34A2 in AEC2s, which reduces intracellular phosphate and represses the phosphorylation of JNK and P38 MAPK, two critical kinases supporting LAR, leading to LAR failure. TRIB3, a stress sensor, interacts with the E3 ligase MDM2 to suppress SLUG degradation in AEC2s by impeding MDM2-catalyzed SLUG ubiquitination. Targeting SLUG degradation by disturbing the TRIB3/MDM2 interaction using a new synthetic staple peptide restores LAR capacity and exhibits potent therapeutic efficacy against experimental PF. Our study reveals a mechanism of the TRIB3-MDM2-SLUG-SLC34A2 axis causing the LAR failure in PF, which confers a potential strategy for treating patients with fibroproliferative lung diseases.

Uncommon epidermal growth factor receptor (EGFR) mutations account for 10%-20% of all EGFR mutations in non-small-cell lung cancer (NSCLC). The uncommon EGFR-mutated NSCLC is associated with poor clinical outcomes and generally achieved unsatisfactory effects to the current therapies using standard EGFR-tyrosine kinase inhibitors (TKIs), including afatinib and osimertinib. Therefore, it is necessary to develop more novel EGFR-TKIs to treat uncommon EGFR-mutated NSCLC. Aumolertinib is a third-generation EGFR-TKI approved in China for treating advanced NSCLC with common EGFR mutations. However, it remains unclear whether aumolertinib is effective in uncommon EGFR-mutated NSCLC. In this work, the in vitro anticancer activity of aumolertinib was investigated in engineered Ba/F3 cells and patient-derived cells bearing diverse uncommon EGFR mutations. Aumolertinib was shown to be more potent in inhibiting the viability of various uncommon EGFR-mutated cell lines than those with wild-type EGFR. And in vivo, aumolertinib could also significantly inhibit tumor growth in two mouse allograft models (V769-D770insASV and L861Q mutations) and a patient-derived xenografts model (H773-V774insNPH mutation). Importantly, aumolertinib exerts responses against tumors in advanced NSCLC patients with uncommon EGFR mutations. These results suggest that aumolertinib has the potential as a promising therapeutic candidate for the treatment of uncommon EGFR-mutated NSCLC.

The cell cycle inhibitor P21 has been implicated in cell senescence and plays an important role in the injury-repair process following lung injury. Pulmonary fibrosis (PF) is a fibrotic lung disorder characterized by cell senescence in lung alveolar epithelial cells. In this study, we report that P21 expression was increased in alveolar epithelial type 2 cells (AEC2s) in a time-dependent manner following multiple bleomycin-induced PF. Repeated injury of AEC2s resulted in telomere shortening and triggered P21-dependent cell senescence. AEC2s with elevated expression of P21 lost their self-renewal and differentiation abilities. In particular, elevated P21 not only induced cell cycle arrest in AEC2s but also bound to P300 and β-catenin and inhibited AEC2 differentiation by disturbing the P300-β-catenin interaction. Meanwhile, senescent AEC2s triggered myofibroblast activation by releasing profibrotic cytokines. Knockdown of P21 restored AEC2-mediated lung alveolar regeneration in mice with chronic PF. The results of our study reveal a mechanism of P21-mediated lung regeneration failure during PF development, which suggests a potential strategy for the treatment of fibrotic lung diseases.

As of 2020， there are more than 120 million diabetic patients in China. Diabetic wounds is one of the common complications of diabetes with increasing incidence and has the potential to cause disability and mortality. Traditional Chinese medicine （TCM） has a long history in treating diabetic wounds， demonstrating significant efficacy and safety. In recent years， increasing researchers have explored the mechanisms of polysaccharides from TCM in the repair of diabetic wounds. Polysaccharides are the main active ingredients of TCM and employ one or more blood sugar-lowering mechanisms. However， most studies focus on the repair mechanism of single polysaccharides， and there is little in-depth discussion and summary. To provide a new therapy for diabetic wounds， which meets international standards and has the characteristics of TCM， and provide reference for the clinical treatment of diabetic wounds， we reviewed relevant literature to summarize the mechanisms of TCM polysaccharides in treating diabetic wounds. The mechanisms include inhibiting inflammation to improve wound microenvironment， lowering blood sugar， promoting fibroblast migration and proliferation， regulating wound growth factor to promote angiogenesis， inhibiting oxidative stress response， and regulating immune function. Finally， we put forward some possible research directions in the future.

Objective:To explore the effect and mechanism of dendritic cell derived exosomes (Dexs) loading ubiquitinated (Ub) hepatitis D antigen (HDAg) on activating specific cytotoxic T lymphocytes (CTL).Methods:Ub-S-HDAg-Dexs were co-cultured with dendritic cells (DC) which were from the femora of C57BL/6 mice for 48 h, then flow cytometry was used to detect the maturity of DC (CD86, CD80 and major histocompatibility complex (MHC) Ⅱ). The spleen-derived T lymphocytes from C57BL/6 mice were added in vitro to activate DC and co-cultivated for 72 h. The T cells were divided into Ub-S-HDAg-Dexs group (add 50 μg/mL Ub-S-HDAg-Dexs), Blank-Dexs group (add 50 μg/mL DC derived exosomes without plasmid transfection), Con-Dexs group (add 50 μg/mL DC derived exosomes transfected by cantrol plasmid), PBS group (add 50 μL/mL phosphate buffered saline), and Ub-S-HDAg-Dexs+ AG490 group (add 50 μg/mL Ub-S-HDAg-Dexs, DC and T lymphocytes stimulated by exosomes, and 50 μmol/L AG490 was also added to the cell mix). Flow cytometry was used to detect CD8 + T cells secreting interferon-gamma, non-radioactive lactate dehydrogenase release test to detect the killing activity of specific CTL. Real-time quantitative polymerase chain reaction (PCR) and Western blotting were used to detect the mRNA and protein expressions of JAK kinase (JAK) 2, GATA-binding protein 3 (GATA3), T-bet, signal transduction and activator of transcription (STAT) 1 and STAT4. Independent sample t test were used for statistical analysis. Results:The positive rates of the surface molecules CD80, CD86, MHCⅡof DC stimulated by Ub-S-HDAg-Dexs were 83.850%±0.219%、68.910%±0.134%、84.320%±0.445%, respectively.In the Ub-S-HDAg-Dexs group, the rate of CD8 + T cells secreting interferon-gamma was 6.420%±0.028%, which was higher than those of other groups, including PBS group, Blank-Dexs group, Con-Dexs group and Ub-S-HDAg-Dexs+ AG490 group ( t=90.78, 30.32, 63.06 and 85.42, respectively, all P<0.001). The cytotoxicity of T cells in the Ub-S-HDAg-Dexs group was 82.4%±3.9%, which was higher than those of other groups ( t=17.28, 9.74, 3.95 and 15.89, respectively, all P<0.050). The relative mRNA expressions of JAK2, T-bet, STAT1, STAT4 in Ub-S-HDAg-Dexs group were higher than those in other groups, including Con-Dexs group ( t=10.74, 32.34, 13.00 and 16.28, respectively, all P<0.001), Blank-Dexs group ( t=15.05, 21.51, 6.46 and 13.12, respectively, all P<0.050), PBS group ( t=21.83, 41.42, 7.30 and 17.50, respectively, all P<0.050), Ub-S-HDAg-Dexs+ AG490 group ( t=35.75, 20.69, 17.02 and 17.07, respectively, all P<0.001), and the differences were all statistically significant. The protein expressions of T-bet, STAT1, STAT4 in Ub-S-HDAg-Dexs group increased compared with those in PBS group ( t=346.70, 57.54 and 55.81, respectively, all P<0.001), with statistical significance. In the presence of AG490, the protein expressions of T-bet, STAT1 and STAT4 decreased compared with those in Ub-S-HDAg-Dexs group, and the differences were statistically significant ( t=355.40, 52.79 and 126.10, respectively, all P<0.001). Conclusions:Ubiquitinated HDAg transported by exosomes could effectively promote DC maturation, induce T lymphocyte differentiation, and generate specific CTL responses, which provides a new idea for the treatment of hepatitis D.