BACKGROUND:Exosomes,as a type of extracellular vesicle,have become a key medium for cell-to-cell communication due to their nanoscale size and enrichment of various bioactive substances.The study of exosome secretion regulation not only has important scientific value,but also has broad application prospects in clinical practice,and is of great significance for promoting medical progress and improving human health.OBJECTIVE:To review the biological characteristics,biological functions,biogenesis process and biochemical regulation mechanism of exosomes,and to explore the application prospects of exosomes in disease diagnosis,treatment and vaccine development,so as to provide theoretical basis and reference for basic research and clinical transformation of exosomes.METHODS:The first author searched PubMed and CNKI databases in October 2024 for relevant literature published from January 2010 to October 2024.Key words were"exosomes,biological functions,biogenesis,secretion or release,regulatory mechanisms,application prospects"in Chinese and English.Finally,92 articles were included for analysis.RESULTS AND CONCLUSION:The secretion level of exosomes can be regulated through physical or biochemical means.Exosomes show broad application prospects in the fields of disease diagnosis,treatment,and vaccine development,and may play a key role in the treatment of cardiovascular and cerebrovascular diseases as well as cancer.This review provides valuable information for the clinical translation and application research of exosomes,helping to promote future progress in exosome research and application.

BACKGROUND:Exosomes,as a type of extracellular vesicle,have become a key medium for cell-to-cell communication due to their nanoscale size and enrichment of various bioactive substances.The study of exosome secretion regulation not only has important scientific value,but also has broad application prospects in clinical practice,and is of great significance for promoting medical progress and improving human health.OBJECTIVE:To review the biological characteristics,biological functions,biogenesis process and biochemical regulation mechanism of exosomes,and to explore the application prospects of exosomes in disease diagnosis,treatment and vaccine development,so as to provide theoretical basis and reference for basic research and clinical transformation of exosomes.METHODS:The first author searched PubMed and CNKI databases in October 2024 for relevant literature published from January 2010 to October 2024.Key words were"exosomes,biological functions,biogenesis,secretion or release,regulatory mechanisms,application prospects"in Chinese and English.Finally,92 articles were included for analysis.RESULTS AND CONCLUSION:The secretion level of exosomes can be regulated through physical or biochemical means.Exosomes show broad application prospects in the fields of disease diagnosis,treatment,and vaccine development,and may play a key role in the treatment of cardiovascular and cerebrovascular diseases as well as cancer.This review provides valuable information for the clinical translation and application research of exosomes,helping to promote future progress in exosome research and application.

Objective To investigate the efficacy of discontinuous density gradient combined with swim-up method for bacterial removal in frozen semen,and to provide experimental evidence for the safe application of frozen semen in assisted reproductive technology.Methods A total of 208 frozen semen samples containing non-pathogenic bacteria,cryopreserved in our human sperm bank from January 2019 to December 2023,were selected.The thawed semen samples were processed using discontinuous density gradient combined with swim-up method.To simulate in vitro fertilization procedures,the processed sperm suspensions were subjected to 5-day in vitro culture for bacterial residue monitoring.Prior to cryopreservation,all semen samples underwent routine bacterial culture to exclude pathogenic microorganisms.Post-thaw semen samples,processed sperm suspensions,and 5-day culture media were sent to an independent third-party laboratory for comprehensive bacterial identification.Results Among the 208 frozen semen samples containing non-pathogenic bacteria,41 bacterial species were identified,with 1～4 species per sample.After processing with discontinuous density gradient combined with swim-up method,the sterility rate of the sperm suspension reached 89.42%(186/208),with residual bacteria including Enterococcus faecalis,Corynebacterium glucuronolyticum,Group B Streptococcus,and Corynebacterium glycinophilum.After 5-day in vitro culture,the sterility rate increased to 93.75%(195/208),with residual bacteria limited to Entero-coccus faecalis and Group B Streptococcus.Conclusions The combined method of discontinuous density gradient and swim-up technique effectively eliminates most bacteria in frozen semen.However,the clearance rate for Entero-coccus faecalis and Group B Streptococcus remains below 90%.Optimization of pre-freezing bacterial screening and post-thaw processing techniques is necessary to enhance the safety of frozen semen in assisted reproductive technology.

BACKGROUND:Eupatilin,a flavonoid active component derived from Artemisia sinensis,has been reported to relieve inflammation and improve neurological scores in rats with subarachnoid hemorrhage,but its role and mechanism in learning and memory remain unclear.OBJECTIVE:To investigate the effects of eupatilin on learning and memory abilities and P38 mitogen activated protein kinase(p38 MAPK)/signal transducer and activator of transcription-3(STAT3)pathway proteins in rats with subarachnoid hemorrhage.METHODS:A total of 50 Sprague-Dawley rats were randomly divided into sham surgery group,model group,eupatilin group,hesperetin group,eupatilin+hesperetin group,with 10 rats in each group.Except for the sham surgery group,the rats in the other groups were used to construct a subarachnoid hemorrhage model through intravascular perforation.Two hours after successful modeling,the eupatilin group was injected with 10 mg/kg eupatilin via the tail vein,the hesperetin group was injected with 50 mg/kg hesperetin(p38 MAPK/STAT3 signaling pathway activator)via the tail vein,the eupatilin+hesperetin group was injected with 10 mg/kg eupatilin and 50 mg/kg hesperetin via the tail vein,and the sham surgery group and the model group were injected with 10 mL/kg saline via the tail vein.The drug treatment lasted for 24 hours.The neurologic deficit score and Morris water maze experiment were applied to detect the neurological function and learning and memory abilities of rats.Hematoxylin-eosin staining was performed to detect the histopathological changes of the hippocampus.TUNEL method was used to detect neuronal apoptosis.Immunohistochemical staining was conducted to detect the number of doublecortin-positive cells in hippocampal tissue.Western blot was applied to detect the expression of p38 MAPK/STAT3 protein in hippocampal tissue.RESULTS AND CONCLUSION:Compared with the sham surgery group,rats in the model group had lower neurological deficit scores,learning and memory abilities,and number of doublecortin-positive cells(P<0.05),and higher neuronal apoptosis rate and protein expression of p-p38 MAPK/p38 MAPK and p-STAT3/STAT3(P<0.05).Compared with the model group,rats in the eupatilin group showed higher neurological deficit scores,learning and memory abilities,and number of doublecortin-positive cells(P<0.05),and lower neuronal apoptosis rate and protein expression of p-p38 MAPK/p38 MAPK and p-STAT3/STAT3(P<0.05),while those in the nerolone group showed lower neurological deficit scores,learning and memory abilities,and number of doublecortin-positive cells(P<0.05),and higher neuronal apoptosis rate and protein expression of p-p38 MAPK/p38 MAPK and p-STAT3/STAT3(P<0.05).Compared with the eupatilin group,rats in the eupatilin+hesperetin group had lower neurological deficit scores,learning memory abilities,and number of doublecortin-positive cells(P<0.05),and higher neuronal apoptosis rate and protein expression of p-p38 MAPK/p38 MAPK and p-STAT3/STAT3(P<0.05).Hematoxylin-eosin staining showed that compared with the model group,the nerve cells were more neatly arranged in the eupatilin group,disorganized in the hesperetin group,and arranged in a similar way to the model group in the eupatilin+hesperetin group.To conclude,eupatilin may improve learning and memory abilities of rats with subarachnoid hemorrhage by inhibiting the p38 MAPK/STAT3 signaling pathway.

OBJECTIVE: To investigate the clinical characteristics and genetic etiology of a fetus with bilateral ear malformation and microphthalmia. METHODS: A fetus diagnosed with Syndromic Microphthalmia 5 (MCOPS5) on January 29, 2024 at Ningbo Women and Children's Hospital was selected as the study subject. A retrospective study was conducted to collect clinical data. Peripheral blood samples (3 mL) were collected from the parents, and amniotic fluid (10 mL) was obtained from the fetus. Genomic DNA was extracted and subjected to whole-exome sequencing (WES). Candidate variants were validated by Sanger sequencing of the family members. The pathogenicity of the candidate variant was classified according to the guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Ethics Committee of Ningbo Women and Children's Hospital (Ethics No.: EC2023-094). RESULTS: The gestational age of the fetus was 23⁺² weeks. Prenatal magnetic resonance imaging (MRI) revealed hypoplastic left external ear, bilateral reduced eyeball volume, and abnormal brain parenchyma development. WES has identified a heterozygous frameshift variant in the OTX2 gene (NM_021728.4: c.706_725del, p.Thr236ProfsTer17). Sanger sequencing confirmed that neither parent has carried the same variant, indicating a de novo origin. According to the ACMG guidelines, this variant was classified as likely pathogenic (PVS1_Strong+PM2_Supporting+PS2_Supporting). CONCLUSION The heterozygous frameshift variant (NM_021728.4: c.706_725del) of the OTX2 gene probably underlay the pathogenesis of this fetus. Above finding has expanded the mutational spectrum of OTX2 gene and may contribute to the understanding of syndromic microphthalmia.
Humans ; Otx Transcription Factors/genetics* ; Female ; Pregnancy ; Phenotype ; Microphthalmos/diagnostic imaging* ; Mutation ; Fetus/abnormalities* ; Male ; Adult ; Retrospective Studies ; Exome Sequencing

Objective To investigate the efficacy of discontinuous density gradient combined with swim-up method for bacterial removal in frozen semen,and to provide experimental evidence for the safe application of frozen semen in assisted reproductive technology.Methods A total of 208 frozen semen samples containing non-pathogenic bacteria,cryopreserved in our human sperm bank from January 2019 to December 2023,were selected.The thawed semen samples were processed using discontinuous density gradient combined with swim-up method.To simulate in vitro fertilization procedures,the processed sperm suspensions were subjected to 5-day in vitro culture for bacterial residue monitoring.Prior to cryopreservation,all semen samples underwent routine bacterial culture to exclude pathogenic microorganisms.Post-thaw semen samples,processed sperm suspensions,and 5-day culture media were sent to an independent third-party laboratory for comprehensive bacterial identification.Results Among the 208 frozen semen samples containing non-pathogenic bacteria,41 bacterial species were identified,with 1～4 species per sample.After processing with discontinuous density gradient combined with swim-up method,the sterility rate of the sperm suspension reached 89.42%(186/208),with residual bacteria including Enterococcus faecalis,Corynebacterium glucuronolyticum,Group B Streptococcus,and Corynebacterium glycinophilum.After 5-day in vitro culture,the sterility rate increased to 93.75%(195/208),with residual bacteria limited to Entero-coccus faecalis and Group B Streptococcus.Conclusions The combined method of discontinuous density gradient and swim-up technique effectively eliminates most bacteria in frozen semen.However,the clearance rate for Entero-coccus faecalis and Group B Streptococcus remains below 90%.Optimization of pre-freezing bacterial screening and post-thaw processing techniques is necessary to enhance the safety of frozen semen in assisted reproductive technology.

ObjectiveTo investigate the liver histopathological features of HBeAg-negative patients in the indeterminate phase of low-viral-load chronic hepatitis B virus （HBV） infection. MethodsA total of 271 patients with low-viral-load HBeAg-negative chronic HBV infection who underwent liver biopsy in Department of Infectious Diseases， Affiliated Hospital of Yan’an University， from September 2013 to June 2021 were enrolled as subjects， and the degree of liver injury was compared between patients based on age， sex， presence or absence of the family history of hepatitis B， HBsAg， and alanine aminotransferase （ALT） level. The chi-square test was used for comparison of categorical data between two groups. ResultsAmong the 271 patients with HBeAg-negative chronic HBV infection， 86 patients （31.73%） grade≥A2 liver inflammatory activity， 72 （26.57%） had a liver fibrosis stage of ive， and 112 （41.33%） had moderate or severe liver histological injury. The proportion of patients with grade≥A2 liver inflammatory activity in the patients with ALT>20 U/L was significantly higher than that in the patients with ALT≤20 U/L （χ²=3.938， P=0.047）. There were no significant differences in the proportion of patients with grade≥A2 liver inflammatory activity between the patients with different ages， sexes， family history of hepatitis B， HBsAg levels （all P>0.05），there were no significant differences in the proportion of patients with a liver fibrosis stage of ≥F2 between the patients with different ages， sexes， family history of hepatitis B， HBsAg， and ALT levels （all P>0.05）， and the stratified analysis of patients aged≤30 years and patients without the family history of hepatitis B showed no statistical significance between groups （all P>0.05）. There was no significant difference in the degree of liver histological injury between the patients with different ages， sexes， family history of hepatitis B， HBsAg， and ALT levels （all P>0.05）. ConclusionSignificant liver injury is observed in more than 40% of the patients with low-viral-load HBeAg-negative chronic HBV infection， and there is no significant difference in the degree of liver histological injury between the patients with different ages， sexes， family history of hepatitis B， HBsAg， and ALT levels. Even for the patients aged≤30 years who deny the family history of hepatitis B， there is still a considerable proportion of patients with liver injury， which should be taken seriously by clinicians.

Objective:To identify candidate strains of Nontoxigenic Clostridioides difficile (NTCD) with potential for intervention in Clostridioides difficile infection (CDI) and analyze their phenotypic characteristics. Methods:A total of 713 Clostridioides difficile strains from various sources were systematically collected nationwide between 2015 and 2023. This included 649 strains isolated from human fecal samples and 64 strains isolated from the fecal samples of farmed animals. NTCD strains were preliminarily screened through toxin gene detection and antibiotic sensitivity test, and then NTCD candidate strains with potential for intervention in CDI were screened by a series of in vitro experiments, including MLST, sporulation, germination, adhesion, motility, and biofilm formation ability. Ultimately, the virulence genes and antimicrobial resistance genes of the candidate strains were comprehensively analyzed to rigorously assess their safety profiles. Results:Among 713 strains of C. difficile from different sources, 10 strains were initially screened out, which were non-toxin-producing and sensitive to antibiotics. MLST showed that seven strains were from the Clade1 branch and three strains were of a novel type. The results of sporulation and germination showed that SD59, SD178, SJZ17, and WZ142 had stronger sporulation and germination abilities. The adhesion of 10 strains was high, and the adhesion rate was between 72.93% and 99.32%. The motility of all strains was different, and the motility of SD178, SD59 and SJZ17 was stronger. The biofilm-forming ability of all strains was weak. SD59, SD178 and SJZ17 carried a limited number of virulence and resistance genes, thereby posing a relatively low safety risk. Conclusion:Three NTCD strains are successfully selected as potential effective NTCD strains to interfere with CDI.

Objective:To analyze the epidemiological characteristics and trend of hospitalization of the patients with herpes zoster in Beijing from 2017 to 2022.Methods:In this retrospective study, the information of hospitalization of herpes zoster patients were collected from all medical institutions at the first level and above in Xicheng, Changping, and Miyun districts of Beijing. The age and gender specific hospitalization rates and age-standardized hospitalization rates were calculated. Joinpoint regression model was used to explore the trend of the hospitalization rates, and the influencing factors of the hospital stay length and complications were analyzed.Results:The age-standardized hospitalization rate of the patients with herpes zoster was 10.82/100 000-18.43/100 000 in Beijing from 2017 to 2022 [annual percent change (APC) =5.86%, 95% CI: -2.80%-15.98%]. The age-standardized hospitalization rate of the cases with herpes zoster as the main diagnosis showed an upward trend (APC=11.35%, 95% CI: 7.21%-16.23%). The age-standardized hospitalization rate showed an upward trend in women (APC=14.34%, 95% CI: 7.95%-22.37%). The hospitalization rate showed a downward trend in age group 30-39 years (APC=-24.92%, 95% CI: -48.56% - -1.85%) and showed upward trends in age group 70-79 years and 80-109 years (APC=23.18%, 95% CI: 13.53%-35.58%; APC=4.90%, 95% CI: 1.18%-9.19%). Complications occurred in 66.28% (680/1 026) of the patients. The median hospital stay length was 9 (5,15) days, and the patients with high age (≥80 years) and two or more complications had longer hospital stay, which were 12 (6, 23) and 14 (7, 27) days respectively ( P<0.001). Conclusions:The hospitalization rate in women and the elderly aged ≥70 years with herpes zoster as the main diagnosis showed upward trends in Beijing in recent years. The elderly aged ≥80 years usually had longer hospital stay, showing a relatively disease burden level. More attention should be paid to development of intervention strategies, such as vaccine, for this population.

Intervention in chronically activated microglia-mediated neuroinflammation is a novel approach to treat Alzheimer's disease (AD). The low permeability of the blood‒brain barrier (BBB) and non-selective distribution in the brain severely restrict AD drugs' disease-modifying efficacy. Here, an immunosuppressant TREM2-lowing antisense oligonucleotides (ASOs) and resveratrol co-loaded cationic liposome is developed as an immune reprogramming nanomodulator modified by acid-cleavable BBB-targeting peptide and microglia-targeting peptide (Res@TcMNP/ASO) for AD management. Res@TcMNP/ASO can enter brain endothelial cells via D-T7 peptides. Then D-T7 undergoes an acid-responsive cleavage, facilitating the escape of Res@MNP/ASO from endo/lysosomes to cross the BBB. The detached Res@MNP/ASO specifically targets M1-phenotype microglia via exposed MG1 peptides to prompt the simultaneous delivery of two drugs into activated microglia. This nanomodulator can not only restore the immune function of microglia through TREM2-lowing ASO but also mitigate the immune stimulation to microglia caused by reactive oxygen species (ROS) through resveratrol, thereby synergistically inhibiting the chronic activation of microglia to alleviate neuroinflammation in AD. Our results indicate that this combination treatment can achieve significant behavioral and cognitive improvements in late APP/PS1 mice.