BackgroundIn recent years， the incidence of depression among adolescents has been increasing steadily， posing a serious threat to their physical and mental health and even leading to severe consequences such as self-harm and suicide. At the same time， the detection rate of subclinical depression symptoms among adolescents is even higher. Although these symptoms do not meet the clinical diagnostic criteria， they have significantly affected their quality of life， and their persistence over time may further develop into depression. Therefore， in-depth exploration of adolescent depression symptoms and the predictive factors holds significant practical significance and research value. However， up to now， no large-scale investigation and research on depression symptoms among children and adolescents has been conducted in Inner Mongolia Autonomous Region. ObjectiveTo understand the prevalence of depressive symptoms among children and adolescents in Inner Mongolia Autonomous Region， in order to provide references for formulating scientific and effective prevention strategies and intervention measures. MethodsBy using the cluster stratified random sampling method， 6 281 students from the third grade of primary school to the second grade of high school in 12 leagues and cities of Inner Mongolia Autonomous Region were selected in March 2024. A self-designed questionnaire and the Self-rating Depression Scale （SDS） were used for on-site investigation. ResultsA total of 6 058 （96.45%） children and adolescents completed the valid questionnaire survey， and 2 728 cases （45.03%） were found to have depressive symptoms. There were statistically significant differences in the detection rates of depressive symptoms among children and adolescents of different genders， ages， whether they were only children， different family types， family monthly income， parents' educational levels， and whether the mother was employed （χ²=33.769， 40.618， 48.593， 29.972， 142.648， 195.999， 168.190， 5.445， P<0.05 or 0.01）.The results of the Logistic regression analysis showed that for children and adolescents， being female， aged between 12 and 16， over 16 years old， not being an only child， living in a reconstituted family， having a monthly family income of less than 5 000 yuan， and having parents with an education level of primary school or below were predictors of depressive symptoms （OR=1.241， 1.427， 1.273， 1.177， 1.549， 1.278， 1.462， 1.417， 1.514， 1.929， 1.660， 1.528， P<0.05 or 0.01）. ConclusionThe detection rate of depressive symptoms among children and adolescents in Inner Mongolia Autonomous Region is relatively high. Factors that may predict depressive symptoms in children and adolescents include female gender， ages between 12 and 16， ages over 16 years old， non-only children， families with a restructured structure， monthly family income of less than 5 000 yuan， and parents with an education level of primary school or below. ［Funded by Science and Technology Planning Project of the Inner Mongolia Autonomous Region （number， 2022YFSH0119）］

BACKGROUND:Research has found that human umbilical cord blood platelet rich plasma and human umbilical cord blood derived mesenchymal stem cells have certain therapeutic effects on thin endometrium.However,there are currently no reports on the study of human umbilical cord blood mononuclear cells on thin endometrium,and there is a lack of relevant research comparing the three.OBJECTIVE:To explore the effects and mechanisms of human umbilical cord blood platelet rich plasma,monocytes,and mesenchymal stem cells in repairing thin endometrium in rats.METHODS:Sixty female SPF grade SD rats were randomly divided into sham operation group,model group,human umbilical cord blood platelet rich plasma group,human umbilical cord blood mononuclear cell group,and human umbilical cord blood derived mesenchymal stem cell group,with 12 rats in each group.The sham operation group received 0.5 mL physiological saline injection into the uterine horn,followed by 0.5 mL of PBS infusion after 5 minutes;The model group,human umbilical cord blood platelet rich plasma group,human umbilical cord blood mononuclear cell group,and human umbilical cord blood derived mesenchymal stem cell group were injected with 0.5 mL of 95％ethanol by volume.After 5 minutes,the remaining ethanol was aspirated and washed twice with physiological saline.Then,0.5 mL of PBS,human umbilical cord blood platelet rich plasma,human umbilical cord blood mononuclear cells(1×107 cells/mL),and human umbilical cord blood derived mesenchymal stem cells(1×107 cells/mL)were perfused separately.During the third normal estrus cycle after reperfusion,organs,tissues and serum were collected for testing of relevant indicators.RESULTS AND CONCLUSION:(1)The macroscopic view of uterine tissue,hematoxylin eosin staining and Masson staining results:the sham operation group had intact structure,moderate endometrial thickness,and clear vascular structure.Compared with the sham operation group,the model group showed uterine atrophy,incomplete structure,significantly reduced endometrial thickness and glandular quantity,disordered vascular structure,and increased fibrosis.Compared with the model group,after treatment with human umbilical cord blood derivatives,the size,structure,and endometrial thickness of the uterus were restored(all P＜0.01),and fibrosis was reduced,with the most significant recovery observed in the human umbilical cord blood mononuclear cell group.The increase in glandular quantity was most significant in the human umbilical cord blood platelet rich plasma group(P＜0.000 1).(2)The immunohistochemistry and immunofluorescence results of uterine tissue showed that compared with the sham operation group,the expression levels of cell proliferation related indicators such as keratin 9 and vimentin,endometrial receptivity related indicators such as leukemia inhibitory factor and integrin αyβ3,platelet endothelial cell adhesion molecule,basic fibroblast growth factor,and vascular endothelial growth factor were all reduced in the model group(all P＜0.05).Compared with the model group,the above indicators were significantly increased after treatment with human umbilical cord blood derivatives.Comparison of human umbilical cord blood derivatives among groups showed that keratin 9 and vascular endothelial growth factor protein:human umbilical cord blood mononuclear cell group＞human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood platelet rich plasma group;Wave shaped protein and leukemia inhibitory factor protein:human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood mononuclear cell group＞human umbilical cord blood platelet rich plasma group;Integrin αyβ3 protein:human umbilical cord blood platelet rich plasma group＞human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood mononuclear cell group;Platelet endothelial cell adhesion molecule protein:human umbilical cord blood platelet rich plasma group＞human umbilical cord blood mononuclear cell group＞human umbilical cord blood derived mesenchymal stem cell group;Basic fibroblast growth factor protein:human umbilical cord blood mononuclear cell group＞human umbilical cord blood platelet rich plasma group＞human umbilical cord blood derived mesenchymal stem cell group.(3)Western blot analysis showed that compared with the sham operation group,the protein levels of interleukin-6,interleukin-1β,and tumor necrosis factor alpha in the model group were significantly increased(all P＜0.001),and their expression levels decreased after treatment(all P＜0.05).(4)ELISA assay showed that compared with the sham operation group,the model group had lower levels of anti Mullerian hormone,estradiol,and progesterone,and increased levels of follicle stimulating hormone and luteinizing hormone(except for luteinizing hormone,all P＜0.05).After treatment,there was a certain degree of recovery in the levels of sex hormones and anti Mullerian hormones.(5)Fertility experiments showed that compared with the sham operation group,the model group had an increase in conception time and a significant decrease in litter size(all P＜0.05).After treatment with human umbilical cord blood derivatives,the litter size of all three groups increased(P＜0.05),and no significant differences were found between the groups.This study preliminarily reveals that human umbilical cord blood mononuclear cells have a certain therapeutic effect on thin endometrium,and human umbilical cord blood platelet rich plasma,human umbilical cord blood mononuclear cells,and human umbilical cord blood derived mesenchymal stem cells have different advantages and differences in improving endometrial regeneration function,endometrial receptivity,angiogenesis,inflammation regulation,and improving pregnancy outcomes in thin endometrium.

BACKGROUND:Research has found that human umbilical cord blood platelet rich plasma and human umbilical cord blood derived mesenchymal stem cells have certain therapeutic effects on thin endometrium.However,there are currently no reports on the study of human umbilical cord blood mononuclear cells on thin endometrium,and there is a lack of relevant research comparing the three.OBJECTIVE:To explore the effects and mechanisms of human umbilical cord blood platelet rich plasma,monocytes,and mesenchymal stem cells in repairing thin endometrium in rats.METHODS:Sixty female SPF grade SD rats were randomly divided into sham operation group,model group,human umbilical cord blood platelet rich plasma group,human umbilical cord blood mononuclear cell group,and human umbilical cord blood derived mesenchymal stem cell group,with 12 rats in each group.The sham operation group received 0.5 mL physiological saline injection into the uterine horn,followed by 0.5 mL of PBS infusion after 5 minutes;The model group,human umbilical cord blood platelet rich plasma group,human umbilical cord blood mononuclear cell group,and human umbilical cord blood derived mesenchymal stem cell group were injected with 0.5 mL of 95％ethanol by volume.After 5 minutes,the remaining ethanol was aspirated and washed twice with physiological saline.Then,0.5 mL of PBS,human umbilical cord blood platelet rich plasma,human umbilical cord blood mononuclear cells(1×107 cells/mL),and human umbilical cord blood derived mesenchymal stem cells(1×107 cells/mL)were perfused separately.During the third normal estrus cycle after reperfusion,organs,tissues and serum were collected for testing of relevant indicators.RESULTS AND CONCLUSION:(1)The macroscopic view of uterine tissue,hematoxylin eosin staining and Masson staining results:the sham operation group had intact structure,moderate endometrial thickness,and clear vascular structure.Compared with the sham operation group,the model group showed uterine atrophy,incomplete structure,significantly reduced endometrial thickness and glandular quantity,disordered vascular structure,and increased fibrosis.Compared with the model group,after treatment with human umbilical cord blood derivatives,the size,structure,and endometrial thickness of the uterus were restored(all P＜0.01),and fibrosis was reduced,with the most significant recovery observed in the human umbilical cord blood mononuclear cell group.The increase in glandular quantity was most significant in the human umbilical cord blood platelet rich plasma group(P＜0.000 1).(2)The immunohistochemistry and immunofluorescence results of uterine tissue showed that compared with the sham operation group,the expression levels of cell proliferation related indicators such as keratin 9 and vimentin,endometrial receptivity related indicators such as leukemia inhibitory factor and integrin αyβ3,platelet endothelial cell adhesion molecule,basic fibroblast growth factor,and vascular endothelial growth factor were all reduced in the model group(all P＜0.05).Compared with the model group,the above indicators were significantly increased after treatment with human umbilical cord blood derivatives.Comparison of human umbilical cord blood derivatives among groups showed that keratin 9 and vascular endothelial growth factor protein:human umbilical cord blood mononuclear cell group＞human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood platelet rich plasma group;Wave shaped protein and leukemia inhibitory factor protein:human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood mononuclear cell group＞human umbilical cord blood platelet rich plasma group;Integrin αyβ3 protein:human umbilical cord blood platelet rich plasma group＞human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood mononuclear cell group;Platelet endothelial cell adhesion molecule protein:human umbilical cord blood platelet rich plasma group＞human umbilical cord blood mononuclear cell group＞human umbilical cord blood derived mesenchymal stem cell group;Basic fibroblast growth factor protein:human umbilical cord blood mononuclear cell group＞human umbilical cord blood platelet rich plasma group＞human umbilical cord blood derived mesenchymal stem cell group.(3)Western blot analysis showed that compared with the sham operation group,the protein levels of interleukin-6,interleukin-1β,and tumor necrosis factor alpha in the model group were significantly increased(all P＜0.001),and their expression levels decreased after treatment(all P＜0.05).(4)ELISA assay showed that compared with the sham operation group,the model group had lower levels of anti Mullerian hormone,estradiol,and progesterone,and increased levels of follicle stimulating hormone and luteinizing hormone(except for luteinizing hormone,all P＜0.05).After treatment,there was a certain degree of recovery in the levels of sex hormones and anti Mullerian hormones.(5)Fertility experiments showed that compared with the sham operation group,the model group had an increase in conception time and a significant decrease in litter size(all P＜0.05).After treatment with human umbilical cord blood derivatives,the litter size of all three groups increased(P＜0.05),and no significant differences were found between the groups.This study preliminarily reveals that human umbilical cord blood mononuclear cells have a certain therapeutic effect on thin endometrium,and human umbilical cord blood platelet rich plasma,human umbilical cord blood mononuclear cells,and human umbilical cord blood derived mesenchymal stem cells have different advantages and differences in improving endometrial regeneration function,endometrial receptivity,angiogenesis,inflammation regulation,and improving pregnancy outcomes in thin endometrium.

ObjectiveTo analyze the microbial culture positivity rate， pathogen spectrum， prevalence of multidrug-resistant organisms （MDROs）， and differences among donor procurement sources in corneas from the Eye Bank of Guangdong Province， and to provide evidence for eye bank quality control and the prevention of post-keratoplasty infections. MethodsThis retrospective study included 7 442 donor corneas procured by the Eye Bank of Guangdong Province and used for keratoplasty at Zhongshan Ophthalmic Center， Sun Yat-sen University， between 2018 and 2025. During surgery， donor corneoscleral rim tissue was excised for bacterial and fungal culture. Culture-positive specimens underwent microbial identification and antimicrobial susceptibility testing （AST）. Culture-positive corneas were compared across study years， pathogen categories， and donor procurement sources. ResultsOf the 7 442 donor corneas， 251 were culture-positive， corresponding to an overall culture positivity rate of 3.37%， with annual rates ranging from 1.50% to 5.31%. Among culture-positive corneas， 178 （70.92%） yielded bacteria alone， 72 （28.68%） yielded fungi alone， and 1 （0.40%） yielded both bacteria and fungi. Candida spp. and Aspergillus spp. were the predominant fungal isolates. Gram-negative bacteria were more frequently isolated than Gram-positive bacteria. The most common bacterial isolates were Acinetobacter baumannii， Staphylococcus epidermidis， Stenotrophomonas maltophilia， Enterococcus faecium， and Pseudomonas fluorescens. MDROs accounted for 75.47% of bacterial isolates， predominantly Acinetobacter baumannii， Staphylococcus epidermidis， and Enterococcus faecium， and demonstrated an increasing trend over the study period. Donor corneas procured through the Hospital Cornea Retrieval Program （HCRP） had a higher culture positivity rate than those obtained through Organ Procurement Organization （OPO） （P＜0.000 1）. Among culture-positive donor corneas， the proportion of fungal culture-positive corneas was significantly higher in the HCRP group than in the OPO group （P=0.001 5）， whereas the proportion of MDROs among bacterial culture-positive corneas was significantly higher in the OPO group than that in the HCRP group （P=0.005 2）. ConclusionsThe overall culture positivity rate of donor corneas from the Eye Bank of Guangdong Province is relatively low， indicating that the risk of microbial contamination is controlled. However， pathogen profiles and antimicrobial resistance patterns varies by procurement source. Ongoing microbiological and antimicrobial resistance surveillance， together with optimized donor risk assessment and timely reporting of culture results， may further improve eye bank quality management and help inform strategies for preventing post-keratoplasty infections.

ObjectiveTo analyze the microbial culture positivity rate， pathogen spectrum， prevalence of multidrug-resistant organisms （MDROs）， and differences among donor procurement sources in corneas from the Eye Bank of Guangdong Province， and to provide evidence for eye bank quality control and the prevention of post-keratoplasty infections. MethodsThis retrospective study included 7 442 donor corneas procured by the Eye Bank of Guangdong Province and used for keratoplasty at Zhongshan Ophthalmic Center， Sun Yat-sen University， between 2018 and 2025. During surgery， donor corneoscleral rim tissue was excised for bacterial and fungal culture. Culture-positive specimens underwent microbial identification and antimicrobial susceptibility testing （AST）. Culture-positive corneas were compared across study years， pathogen categories， and donor procurement sources. ResultsOf the 7 442 donor corneas， 251 were culture-positive， corresponding to an overall culture positivity rate of 3.37%， with annual rates ranging from 1.50% to 5.31%. Among culture-positive corneas， 178 （70.92%） yielded bacteria alone， 72 （28.68%） yielded fungi alone， and 1 （0.40%） yielded both bacteria and fungi. Candida spp. and Aspergillus spp. were the predominant fungal isolates. Gram-negative bacteria were more frequently isolated than Gram-positive bacteria. The most common bacterial isolates were Acinetobacter baumannii， Staphylococcus epidermidis， Stenotrophomonas maltophilia， Enterococcus faecium， and Pseudomonas fluorescens. MDROs accounted for 75.47% of bacterial isolates， predominantly Acinetobacter baumannii， Staphylococcus epidermidis， and Enterococcus faecium， and demonstrated an increasing trend over the study period. Donor corneas procured through the Hospital Cornea Retrieval Program （HCRP） had a higher culture positivity rate than those obtained through Organ Procurement Organization （OPO） （P＜0.000 1）. Among culture-positive donor corneas， the proportion of fungal culture-positive corneas was significantly higher in the HCRP group than in the OPO group （P=0.001 5）， whereas the proportion of MDROs among bacterial culture-positive corneas was significantly higher in the OPO group than that in the HCRP group （P=0.005 2）. ConclusionsThe overall culture positivity rate of donor corneas from the Eye Bank of Guangdong Province is relatively low， indicating that the risk of microbial contamination is controlled. However， pathogen profiles and antimicrobial resistance patterns varies by procurement source. Ongoing microbiological and antimicrobial resistance surveillance， together with optimized donor risk assessment and timely reporting of culture results， may further improve eye bank quality management and help inform strategies for preventing post-keratoplasty infections.

BACKGROUND:Spleen has the functions of blood storage,hematopoiesis,and immunity.With the increase of age,the structural degeneration and functional decline of spleen lead to the impairment of immune system function,thus accelerating the aging process of the body.The treatment of spleen aging in tree shrews with highly active umbilical cord mesenchymal stem cells has not been reported. OBJECTIVE:To explore the intervention effect and mechanism of highly active umbilical cord mesenchymal stem cells on spleen aging in tree shrews. METHODS:Highly active umbilical cord mesenchymal stem cells were isolated,cultured,and obtained from the umbilical cord tissue of newborn tree shrews by caesarean section.The differentiation abilities of adipogenesis,osteogenesis,and chondrogenesis were detected by three-line differentiation kit.Cell cycle and surface markers were detected by flow cytometry.The second generation of highly active umbilical cord mesenchymal stem cells were transfected with Genechem Green Fluorescent Protein with infection complex values of 100,120,140,160,180,and 200,respectively,to screen the best transfection conditions.After transfection,the fourth generation of highly active umbilical cord mesenchymal stem cells was injected into the tail vein of tree shrews in the elderly treatment group.The young control group and the aged model group were not given special treatment.After 4 months of treatment,the spleen tissue was taken and the structure of the spleen was observed by hematoxylin-eosin staining.β-Galactosidase staining was used to detect the activity of aging-related galactosidase.Immunohistochemical staining was used to detect the expression levels of p21 and p53 proteins.Ki67 and PCNA immunofluorescence staining was used to detect cell proliferation activity.Immunofluorescence staining was used to detect the expression levels of spleen autophagy protein molecules Beclin 1 and APG5L/ATG5.Reactive oxygen species fluorescence staining was used to detect the content of reactive oxygen species in spleen tissue.CD3 immunofluorescence staining was used to detect the change of the proportion of total T lymphocytes.The secretion levels of interleukin 1β and transforming growth factor β1 in spleen were detected by enzyme linked immunosorbent assay.The distribution of highly active umbilical cord mesenchymal stem cells labeled with green fluorescent protein in spleen tissue was observed by DAPI double staining of nucleus. RESULTS AND CONCLUSION:(1)Highly active umbilical cord mesenchymal stem cells grew in a short spindle shape with fish-like growth,with a large proportion of G0/G1 phase,and had the potential to differentiate into adipogenesis,osteogenesis,and chondrogenesis.(2)Multiplicity of infection=140 and transfection for 72 hours were the best conditions for labeling tree shrews highly active umbilical cord mesenchymal stem cells with Genechem Green Fluorescent Protein.(3)Compared with the aged model group,in the aged treatment group,the spleen tissue cells of tree shrews were arranged closely,and the area of white pulp was increased(P<0.01);the boundary between red pulp and white pulp was clear;the proportion of germinal centers did not show statistically significant difference(P>0.05).The activity level of galactosidase related to spleen tissue aging was decreased(P<0.001),and the expression levels of aging protein molecules p21 and p53 were down-regulated(P<0.001).The expression levels of proliferation-related molecules Ki67 and PCNA were up-regulated(P<0.001,P<0.05);expression levels of autophagy-related molecules Beclin 1 and APG5L/ATG5 were up-regulated(P<0.001),and the content of reactive oxygen species decreased(P<0.001),and the proportion of CD3+T cells increased(P<0.05).The secretion level of interleukin 1β in the aging-related secretion phenotype decreased(P<0.001);no significant difference was found in transforming growth factor β1 level(P>0.05).Compared with the young control group,the above indexes were significantly different in the elderly treatment group(P<0.05).(4)Green fluorescent cells labeled with green fluorescent protein were observed in spleen tissue of tree shrews the elderly treatment group by frozen tissue section observation.The results show that intravenous infusion of highly active umbilical cord mesenchymal stem cells can migrate to spleen tissue,inhibit the production of reactive oxygen species,down-regulate the expression of aging-related proteins,induce autophagy,promote cell proliferation,reduce chronic inflammation,and then improve the structure and function of spleen tissue.

“Chinese Pharmacopoeia” is the legal basis for drug development, production, operation, use and management in China, and the Chinese Pharmacopoeia 2025 Edition is going to be issued and implemented. This article introduces the revision and amendment situations, analyzes the characteristics of the new edition of the Pharmacopoeia and the future development direction of national standards for better understanding and implementation of the latest edition of pharmacopoeia.

[Objective] To explore the accuracy and feasibility of non-invasive prenatal diagnosis of fetal RhE genotype using cell-free fetal DNA (cff-DNA) from maternal peripheral blood. [Methods] A total of 134 pregnant women with single fetuses and RhE-negative blood group were selected from our hospital from November 2023 to August 2024. Free DNA extraction kit was used to extract free DNA from peripheral blood of pregnant women, and the RhE blood group genotype of free DNA was detected by real-time fluorescent quantitative PCR (RT-qPCR). If the qPCR amplification signal of the sample was negative, the methylated RASSF1A gene was amplified, and the positive amplification result was used as a sign of successful extraction of cff-DNA. Serological microcolumn gel method was used to detect the phenotype of RhE blood group in neonatal peripheral blood. [Results] Among the 134 maternal peripheral blood samples, the cff-DNA detection of RhE blood group phenotypes was consistent with the RhE blood group genotyping of neonatal peripheral blood in 133 cases, including 90 cases of Rhee genotype and 43 cases of RhE genotype, with diagnostic concordance rate of 99.3%, sensitivity of 97.7%, specificity of 100%, youden index of 0.977, area under ROC curve of 0.995, the Kappa value of 0.983, positive predictive value of 100%, and negative predictive value of 98.9%. The sample of 1 case failed to be detected. After the amplification of methylated RASSFIA gene, it was confirmed that the reason for the failure was that no cff-DNA was extracted from the sample. The diagnostic concordance rates of the first, second and third trimesters were 93.8% (15/16), 100% (51/51) and 100% (67/67), respectively. Fisher's exact test method was used to calculate the P value, which was P>0.05, indicating that there was no statistical significance in the difference of diagnostic concordance rate among the three pregnancy periods, and there was no difference in the detection concordance rate of this method in different pregnancy periods. [Conclusion] The use of cff-DNA in maternal peripheral blood for the detection of fetal RhE blood group genotype is an accurate and highly feasible non-invasive prenatal diagnostic method, which is helpful for the clinical diagnosis of fetal and neonatal hemolytic disease caused by anti-E antibody.

Objective:To investigate the epidemiological trends of viral diarrhea pathogens in children in Baotou city, and to provide reference for controlling the prevalence of viral diarrhea and guiding the development of regional vaccines.Methods:Fecal samples were collected from children under five years old hospitalized with viral diarrhea at two sentinel hospitals in Baotou from June 2023 to May 2024. Real-time PCR was used to detect group A rotavirus, norovirus, adenovirus, and astrovirus. Statistical analysis was performed using SPSS 20.0 software, with Chi-square tests conducted to assess differences. A P value<0.05 was considered statistically significant. Results:A total of 246 fecal samples were collected, including 153 from males and 93 from females. Among these, 135 samples tested positive, yielding a positivity rate of 54.88% (135/246). There were 82 positive samples from male children and 53 from female children, with no significant difference between genders. Most positive samples (51.85%, 70/135) tested positive for two viruses. Specifically, co-infections of group A rotavirus with norovirus or adenovirus accounted for 98.57% (69/70) of all co-infected cases. Significant differences in detection rates were observed across age groups (χ 2=29.803, P<0.001), with the highest positivity rates in children under one year old and in the 1-year age group. Seasonality, viral diarrhea in Baotou was more prevalent in winter and spring. The G8P[8] genotype of group A rotavirus was the predominant strain. Conclusions:From June 2023 to May 2024, viral diarrhea in hospitalized children under five years old in Baotou is primarily caused by co-infections of group A rotavirus and norovirus, with a higher incidence in preschool-aged children. The G8P[8] genotype of group A rotavirus is the dominant strain. It is recommended to strengthen vaccination and surveillance efforts for viral diarrhea in preschool children, particularly during the winter and spring seasons.

Objective:To analyze the epidemiological characteristics of influenza-like illness（ILI）and the genetic evolutionary trends of the hemagglutinin（HA）and neuraminidase（NA）genes of influenza A（H3N2）viruses isolated in Baotou during the 2022-2023 influenza season.Methods:Etiological surveillance data for ILI cases in Baotou during the 2022-2023 influenza season were collected from the China Influenza Surveillance Information System. Descriptive statistical analysis was performed on the data. HA and NA genes of 30 influenza A（H3N2）viruses were sequenced. Amino acid variation sites，glycosylation sites，drug resistance genes，and phylogenetic trees were analyzed using MEGA 11 software and the NextClade online analysis tool.Results:A total of 1 443 ILI specimens were tested，of which 241（16.70%）were positive for influenza viruses. Among the positive cases，influenza A（H3N2）virus-positive cases accounted for 75.93%（183/241）. The nucleotide sequence similarity of the HA gene between the 30 influenza A（H3N2）isolates and the vaccine strains A/Hong Kong/2671/2019（H3N2），A/Cambodia/e0826260/2020（H3N2），and A/Darwin/9/2021（H3N2）ranged from 96.83% to 98.77%，while the amino acid sequence similarity ranged from 94.63% to 99.62%. A total of 14 amino acid variation sites and 11 conserved glycosylation sites were identified in the HA gene. For the NA gene，the nucleotide sequence similarity ranged from 98.37% to 99.65%，and the amino acid sequence similarity ranged from 94.64% to 98.28%. A total of three amino acid variation sites and nine conserved glycosylation sites were found in the NA gene. None of the 30 influenza A（H3N2）isolates had mutations associated with drug resistance，and all belonged to the clade 3C.2a1b.2a.2a.3a.1.Conclusions:During the 2022-2023 influenza season in Baotou，the circulating influenza A（H3N2）viruses belong to the same evolutionary clade as the 2021-2022 vaccine strain A/Cambodia/e0826360/2020（H3N2）. The isolates from different sources share a common evolutionary origin；however，variations are observed across the genome in terms of homology，molecular mutations，and glycosylation patterns.