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 compare and analyze the antibacterial effects of platelets against five common clinical pathogenic bacteria including MRSA, SE, SA, E. coli, and CRKP, and to preliminarily explore the role of DCD sensitivity in the observed variations of antibacterial effects. Methods: The same number of platelets were used to establish co-culture systems of platelets and platelet lysates with the five pathogenic bacteria. The antibacterial effects of platelets and platelet lysates on the five pathogenic bacteria were evaluated by observing the turbidity of the bacterial solution, measuring the OD value of the bacterial solution and counting the colonies. The supernatant protein of platelets co-cultured with MRSA was collected for quantitative proteomics analysis to explore the important antibacterial proteins of platelets. The content of DCD in the supernatant after co-culture of platelets and platelet lysates with the five pathogenic bacteria was detected by ELISA to preliminarily analyze the reasons for the different antibacterial effects of platelets on the five pathogenic bacteria. Results: Compared with the control group of MRSA, SA, and SE, the turbidity of the bacterial solution decreased after co-culture of platelets and platelet lysates with MRSA, SA, and SE for 12 h, and the OD value and colony count were significantly reduced (P<0.05). The turbidity of the bacterial solution did not change significantly after co-culture of platelets and platelet lysates with E. coli for 24 h, but the OD value decreased (P<0.05), and the colony count decreased to 10 CFU/mL but the difference was not statistically significant (P>0.05). Compared with the control group of CRKP, the turbidity, OD value, and colony count of the bacterial solution did not change significantly after co-culture of platelets and platelet lysates with CRKP (P>0.05). Proteomics results showed that after co-culture with MRSA, important proteins related to platelet activation, including collagen, fibrinogen, von Willebrand factor, integrin αIIbβ3, platelet glycoprotein V and IV were significantly up-regulated. ELISA results showed that after co-culture with the five pathogenic bacteria, platelets could secrete a large amount of DCD, with the content around 3 μg/mL. Conclusion: The antibacterial effect of platelets on Gram-positive bacteria MRSA, SA, and SE is better than that on Gram-negative bacteria E. coli and CRKP, and platelets have the best antibacterial effect on MRSA. The differences in antibacterial effects of platelets on the five pathogenic bacteria may be related to the sensitivity of DCD antibacterial peptides to the five pathogenic bacteria.

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.

AIM: To investigate the effects of hypobaric hypoxia in plateau on tear indexes and related anatomical structures in rabbits.METHODS: A total of 18 healthy New Zealand rabbits were selected and randomly divided into plateau group and control group, with 9 rabbits(18 eyes)in each group. The plateau group was housed in the Simulated Climate Cabin for Special Environment of Northwest of China, simulating hypobaric hypoxia at an altitude of 6 000 m. The control group was housed in a clean animal room with atmospheric pressure and oxygen. Changes in the tear meniscus height and non-invasive tear break-up time were detected by using RHCT-1 corneal topographer dry eye comprehensive analysis system, changes in tear secretion was measured by Schirmer Ⅰ test, before intervention and on the 3, 7 d, 2 and 4 wk. Meanwhile, the changes in tear composition before and after intervention in the plateau environment were analyzed using Raman Spectroscopy. The histopathological changes of the lower lid conjunctiva, cornea, lacrimal gland, and Hardarian gland were observed by hematoxylin-eosin(HE)staining after 4 wk of intervention, and the expression of mucin 5AC(MUC5AC)in conjunctiva was detected by immunohistochemistry.RESULTS: Compared with the control group, Schirmer Ⅰ test, tear meniscus height, first and average non-invasive tear break-up time in the plateau group decreased significantly since 3 d, and the difference was significant with the extension of observation time(P<0.05). The above indexes increased from 2 wk. After 4 wk of intervention, the protein and lipid content of the tear composition of rabbits in the plateau group increased, and the nucleic acid content decreased compared with the pre-intervention period. Compared with the control group, rabbits in the plateau group showed thickening of corneal stromal edema, an increase in the number of conjunctival cup cells, increase in the level of expression of MUC5AC, an increase in the level of expression of MUC5AC, an atrophy and flattening of cytoplasm in lacrimal epithelial cells, an enlargement of glandular lumen, and no obvious destructive changes in the Hardarian glands.CONCLUSION: Acute plateau environment can destroy the homeostasis of rabbit ocular surface, so that the tear secretion and the tear film stability decreases, but within a certain period of time, rabbits undergo compensation with the habituation to the hypobaric hypoxia environment, which can increase the tear secretion to a certain extent and restore the tear film stability.

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.

ObjectiveTo analyze the research status and trends in low-level occupational benzene exposure. Methods Articles on low-level occupational benzene exposure from Chinese and English journals from January 1st, 2000, to December 31th, 2022 were retrieved using the Web of Science and the China National Knowledge Infrastructure, and a bibliometric analysis was conducted. Results A total of 327 articles were included in the analysis, comprising 216 English articles and 111 Chinese articles. i) The number of articles published in English fluctuates greatly over the years, without a trend of continuous growth or decline. Authors from 359 research institutions in 45 countries and regions have published relevant English articles in 97 kinds of journals, involving 281 grants from 226 foundations. The top three countries in terms of articles amount were the United States, Italy, and China, with 81, 46, and 43 papers, respectively. The English articles mainly focused on mechanistic research at the genetic level, such as hematotoxicity, oxidative stress, and DNA damage. ii) The number of Chinese articles increased gradually after 2012, with the growth peak in 2017. Authors from 127 research institutions in 26 provinces, autonomous regions, and municipalities published Chinese articles in 51 kinds of journals, involving 154 grants from 78 foundations. Chinese articles tended to focus on benzene-induced hematotoxicity and occupational health damage. Conclusion Most studies on low-level occupational benzene exposure were conducted in China, the United States and Italy, focused on hematotoxicity. Monitoring international research topics and hotspots of the field has certain reference value for related research in China.

Objective To analyze the current status,hot spots and trends of Chinese and English researches in the field of aspiration after dysphasia in the past twenty years. Methods The articles about aspiration after dysphasia were retrieved from CNKI and Web of Science(WOS)core collec-tion database,from January,2003 to June,2023,and were analyzed with CiteSpace 6.1.R6. Results A total of 3 231 articles were included.The annual articles were published more and more year by year.The most English literatures came from the United States.Hot spots mainly focused on the assessment of dysphasia,prevention of complication,nutrition and rehabilitation therapy.It would concentrate on the application of the volume-viscosity swallow test and assessment scales,rehabilitation,penetration aspiration,outcome and effect validation,quality of life,feeding and nutrition condition,and evidence-based nursing,etc.,in the future. Conclusion The researches in the field of aspiration after dysphasia have been increasing in recent years,and the themes and contents of researches have been deepening.

Objective:To construct and purify four respiratory syncytial virus (RSV) PreF proteins through gene sequence design and optimization and evaluate their immunogenicity.Methods:Coronin-1A and T4 trimer protein gene sequences were optimized with Human and CHO codons, and then added to RSV F protein sequence. The above plasmids were transfected into Expi293F cells for protein expression. After purification by nickel column, four trimer proteins were prepared. SDS-PAGE and Western blot were performed for protein identification. BALB/c mice were immunized at week 0 and week 3, and blood samples were collected to measure the activities of binding and neutralizing antibodies in serum.Results:SDS-PAGE and Western blot showed that the four proteins had stable trimer structure. Antigen-antibody affinity test showed that the four trimer proteins had strong affinity with RSV-specific monoclonal antibodies 8897, D25, Motavizumab, AM14 and Palivizumab. The titers of antibodies induced by the two T4 trimers were higher after the initial immunization, while there was a substantial increase in the titers of antibodies induced by Human codon-optimized trimer protein after the second immunization.Conclusions:PreF trimer protein can be prepared by adding any of the two different heterotrimer motifs, and induce effective binding and neutralizing antibodies in mice.

The examinations of tear quality and volume are important indicators for the diagnosis of dry eye disease. Tests commonly used in clinical practice to diagnose dry eye disease include testing of tear volume and tear film stability to assess the severity of the condition, and analyzing and labeling of tear components under laboratory conditions to diagnose clinical staging and also to guide clinical supplementation of relevant components to target treatment. Accurate assessment of tear production and compositional changes enables clinicians to effectively monitor the severity of dry eye disease and evaluate the effectiveness of therapeutic measures. With the development of optical imaging technology and artificial intelligence in recent years, the combination of clinical tear indicators and examination techniques has enabled the application of new testing methods that provide more convenient, rapid and accurate testing, greatly improving the diagnosis and treatment of dry eye disease in the clinic.

ObjectiveTo explore the influence of "Internet plus" postpartum health care service on postpartum depression, and to provide an evidence for reducing the incidence of postpartum depression and improving the quality of life for postnatal women. MethodsMothers who gave birth between August 1, 2021 and June 30, 2023 lived in the six streets of Xuhui District were selected as the research subjects. The puerperants were randomly divided into the intervention group and the control group according to the order of enrollment using a numerical numbering system, with 210 cases in each of the intervention group and control group. The intervention group adopted the "Internet plus" postpartum health care services, while the control group adopted the conventional postpartum health care services. The risk factors related to postpartum mental health and the incidence of postpartum depression were compared between the two groups. ResultsThere was no statistically significant difference in the scores of postpartum mental health-related risk factors between the two groups at the first 2 weeks and 1st month after delivery (t=0.736 and t=1.260, P>0.05). However, there was a statistically significant difference in the scores of postpartum mental health-related risk factors at the 3rd months after delivery and 6th months after delivery (t=2.089, P<0.05; t=2.655, P<0.05). There was no statistically significant difference in depression scores at the first 2 weeks after the birth (t=0.560, P>0.05). In the 1st month, the 3rd month and the 6th month after delivery, the intervention group adopted the "Internet plus" postpartum health care service, thus the differences in depression scores were statistically significant (t=2.616, t=2.793 and t=3.107, P<0.05). Conclusion"Internet plus" postpartum health care service is conducive to reducing postpartum depression, promoting maternal mental health, and significantly improving the well-being of postnatal women.