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.

Selection markers are essential tools in gene editing, the utility of such systems is inherently constrained by species-specific limitations, governed by divergent host genetic backgrounds and metabolic compatibility. To address this limitation, we leveraged the CRISPR/Cas9 system to develop a universal counter-selection tool. We designed and introduced an sgRNA expression cassettes as counter-selection markers, which directs the Cas9 protein to target and cleave genomic DNA, allowing for the selection of the strains where the sgRNA expression cassette has been replaced. Optimized to target multiple copy sites with sgRNA, this system significantly enhances cell lethality, boosting counter-selection efficiency to over 85.00%. This counter-selection tool is not limited to single strains and is suitable for various scenarios, including multi-copy plasmid assembly and plasmid editing, demonstrating broad application potential.
CRISPR-Cas Systems/genetics* ; Gene Editing/methods* ; RNA, Guide, CRISPR-Cas Systems/genetics* ; Plasmids/genetics*

Objective To assess the prevalence of mycoplasma genitalium(MG)in patients attending sexually transmitted disease(STD)clinic in Guangzhou,and to provide an epidemiological foundation for clinical treatment and laboratory diagnostics.Methods Utilizing real-time polymerase chain reaction(PCR),we analyzed MG DNA in 2,749 clinical specimens collected from 2,722 outpatients in the Dermatology Hospital of Southern Medical University from July 2019 to December 2021.Concurrent testing for MG,Chlamydia trachomatis(CT),and Neisseria gonorrhoeae(NG)was performed on 2,382 of these specimens.Patient data extracted from medical records were used to investigate the correlation between STD symptoms and MG infection.Results The investigation revealed that the overall prevalence of MG infection was 4.4%among the sampled patients(120 out of 2,722),with a higher prevalence in males(4.9%,or 87 out of 1,790)compared to in females(3.5%,or 33 out of 932).Notably,the prevalence decreased with increasing age.The highest incidence of MG infection was observed in females aged 18～25 years(6.4%,or 18 out of 281),while the lowest was in males aged 46 years and above(1.5%,or 5 out of 342),showing a statistically significant variation across age groups(P<0.05).Among males with urethritis symptoms,MG positive rate was significantly higher at 7.3%(42 out of 574).The rate of single MG infection was prominent,accounting for 89.9%(71 out of 79)in MG-positive male patients and 61.5%(16 out of 26)in MG-positive female patients.Co-infection rate of MG with CT was 1.2%in females and 0.3%in males,indicating a significant dif-ference(P<0.05).Conclusion The findings suggest a relatively high prevalence of MG infection and co-infection with CT among STD clinic attendees in Guangzhou,particularly in the younger demographic.The study underscores the need for early screening and vigilant surveillance of MG to mitigate its transmission among sexually active popula-tions at high risk.

ObjectiveTo observe the clinical effectiveness and safety of Sanjie Waifu Formula （散结外敷方） application therapy for benign thyroid nodules of qi constraint and phlegm obstruction syndrome. MethodsEighty patients with benign thyroid nodules of qi constraint and phlegm obstruction syndrome were randomly divided into 40 cases each in a treatment group and a control group. The control group was given health education and follow-up observation， while the treatment group applied Sanjie Waifu Formula externally on the basis of the control group，6~8 h each time ， once a day. Both groups took 30 days as a course， and were observed for 3 consecutive courses. The main effectiveness indexes of both groups were compared before and after treatment， including the volume of thyroid nodules， the maximum diameter of the largest nodule， the scores of traditional Chinese medicine （TCM） syndrome， and the secondary effectiveness indexes of serum thyroid function including free triiodothyronine （FT₃）， free thyroxine （FT₄）， thyrotropin （TSH） levels were also observed. The effectiveness of the TCM syndrome of both groups was compared after treatment. Meanwhile， the safety indexes were observed before and after treatment， such as the blood routine， liver and kidney function indexes， and the occurrence of adverse reactions during the study was recorded. ResultsCompared with in group before treatment， the volume of thyroid nodules， the maximum diameter of the largest nodule， and the TCM symptom scores were lowered in both groups after treatment （P＜0.05 or P＜0.01）. Comparing between groups after treatment， the difference in thyroid nodule volume was not statistically significant （P＞0.05）， but the maximum diameter of the largest nodule and the TCM symptom scores of the treatment group were lower than those of the control group （P＜0.01）. The total effective rate of TCM syndrome in the treatment group was 77.50% （31/40）， which was significantly higher than that of the control group with 52.5% （21/40， P＜0.01）. Thyroid function， blood routine and liver and kidney function indexes of both groups before and after treatment were compared between and within groups， and the differences were not statistically significant （P＞0.05）， and they were all within the normal range. During the treatment period， no allergic reactions such as skin itching， red rash and blisters occurred in the treatment group. ConclusionThe external application of Sanjie Waifu Formula can improve the clinical symptoms of patients with benign thyroid nodules， reduce volume and the maximum diameter of nodules， and has no significant effects on thyroid function and show good safety.

Objective:To investigate the prevalence of adult skeletal fluorosis caused by drinking tea-type endemic fluorosis in Yushu Tibetan Autonomous Prefecture (hereinafter referred to as Yushu Prefecture), Qinghai Province, and provide scientific basis for prevention and control of the disease.Methods:In August 2021, one village was selected as a survey site in six counties (cities) in Yushu Prefecture, including Nangqian, Chindu, Yushu, Zadoi, Qumarlêb, and Zhiduo. Drinking water samples and 10 brick tea samples were collected from each village to determine the fluoride content in water and brick tea; at least 100 permanent residents aged ≥ 25, who had a habit of drinking brick tea and had lived in the local area for more than 5 years, were selected for X-ray imaging to examine the prevalence of adult skeletal fluorosis.Results:A total of 75 samples of residential drinking water were collected, with a fluoride content of (0.21 ± 0.05) mg/L, ranging from 0.11 to 0.34 mg/L; 60 samples of brick tea, with a fluoride content of (626.70 ± 157.27) mg/kg, ranging from 324.00 to 2 102.00 mg/kg. A total of 1 136 adults were examined, and 318 cases of skeletal fluorosis were diagnosed, with a detection rate of 27.99%. Among them, the detection rates of mild, moderate, and severe skeletal fluorosis were 20.95% (238/1 136), 6.07% (69/1 136), and 0.97% (11/1 136), respectively, with mild symptoms being the main. The detection rates of skeletal fluorosis in males and females were 29.09% (121/416) and 27.36% (197/720), respectively, with no statistically significant difference between the gender (χ 2 = 0.39, P = 0.533). Comparison of the skeletal fluorosis in different gender, the differences were statistically significant (χ 2 = 22.31, P < 0.001). The detection rates of skeletal fluorosis in the age groups of 25 - 35, 36 - 45, 46 - 55, 56 - 65, 66 - 75, and ≥76 years old were 6.86% (7/102), 22.37% (51/228), 24.02% (92/383), 37.44% (73/195), 43.48% (70/161), and 37.31% (25/67), respectively. The differences between the groups were statistically significant (χ 2 = 59.84, P < 0.001). Moreover, there was a statistically significant difference in the composition of skeletal fluorosis among different age groups ( H = 37.66, P < 0.001). The Spearman correlation analysis results showed that the severity of adult skeletal fluorosis was positively correlated with age ( r = 0.34, P < 0.001). Conclusions:There is a certain degree of prevalence of adult skeletal fluorosis in Yushu Prefecture. And as age increases, the condition of skeletal fluorosis becomes more severe.

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.

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.