Radiotherapy is a crucial treatment modality for head and neck tumors. However, while effectively killing tumor cells, it significantly disrupts the homeostasis of the oral microecology, which is closely associated with various complications such as radiation-induced oral mucositis. Literature review indicates that as radiotherapy doses accumulate and treatment durations extend, the richness and diversity of the oral microbiota show a declining trend, with the genus Streptococcus decreasing most markedly. In contrast, radiotherapy selectively promotes the proliferation of bacterial phyla such as Proteobacteria and Bacteroidetes, which are rich in opportunistic pathogens. Mechanistically, radiotherapy activates the nuclear factor-kappa B pathway, triggering chronic inflammation and oxidative stress, damaging the epithelial barrier, suppressing local immunity, and causing damage to organs such as the salivary glands. It can also induce systemic diseases via the oral-gut axis, forming a multi-level, interconnected pathogenic network. In terms of interventions, treatment strategies including probiotics and prebiotics have shown promising efficacy against side effects such as radiation-induced oral mucositis. Saliva-based oral microbiota transplantation is an emerging strategy that is expected to become widely utilized for restoring oral microecological balance. Existing interventions provide preliminary pathways for clinical practice, but this field still faces several key scientific questions. The association between oral microecology and systemic diseases remains largely correlative, lacking causal evidence. Furthermore, critical parameters for oral microbiota transplantation, such as donor screening criteria, transplantation protocols, and long-term safety, are not yet well-defined. Therefore, future research should focus on conducting large-scale clinical trials to establish standardized protocols and safety evaluation systems for oral microecological interventions, and explore combined treatment therapies such as probiotics, prebiotics, and microbiota transplantation to advance the development of personalized precision modulation. These will enable more effective management of radiotherapy-induced oral microecological dysbiosis and improve treatment outcomes and quality of life for patients with head and neck tumors.

ObjectiveTo explore the mechanisms of Qingchang Wenzhong Decoction （清肠温中方， QWD） in treating ulcerative colitis （UC）. MethodsA total of 100 male C57BL/6J mice were assigned to a pseudo-germ-free group （n=45） and a conventional group （n=55） using a random number table. Pseudo-germ-free model was established by giving antibiotic treatment and subsequently subjected to acute UC induction. After the model was successfully established， the 45 pseudo-germ-free acute UC mice were randomly allocated to a pseudo-germ-free model group， a pseudo-germ-free QWD group， and a pseudo-germ-free mesalazine group， with 15 mice in each group. The 55 conventional mice were randomly divided into a normal control group （n=10）， as well as a conventional model group， a conventional QWD group， and a conventional mesalazine group， with 15 mice in each group. Except for the normal control group， acute UC models were established in all other groups. Mice in the control group received no intervention. From day 32 of the experiment， mice in the pseudo-germ-free QWD group and the conventional QWD group were administered with QWD granules at a dose of 9.71 g/（kg·d） by gavage with deionized water， while those in the pseudo-germ-free mesalazine group and the conventional mesalazine group were given mesalazine enteric-coated tablets at a dose of 151.67 mg/（kg·d） by gavage. Mice in the remaining groups received an equal volume of deionized water once daily for 7 consecutive days. On day 25 of the experiment， six mice were randomly selected from both the pseudo-germ-free group and the conventional group to measure body weight， and fecal samples were collected for 16S rDNA sequencing to compare differences in gut microbiota， including operational taxonomic units （OTUs）， Shannon index， Observed_species index， and phylogenetic diversity （PD whole tree）. On day 39， body weight was measured in all groups， and the disease activity index （DAI） was evaluated. Colon length and colon wet weight were recorded. Histopathological changes in colonic tissues were assessed by hematoxylin and eosin （HE） staining， and histological injury scores were determined. In addition， the expression levels of mucopolysaccharides and mucin 2 （MUC2） in colonic tissues were measured. ResultsOn day 25， there was no significant difference in body weight between the pseudo-germ-free group and the conventional microbiota group （P＞0.05）. Compared to the conventional microbiota group， the pseudo-germ-free group showed significantly reduced OTUs， Shannon index， Observed_species index， and PD whole tree （P＜0.01）. On day 39， compared to the normal control group， mice in the conventional model group showed a significant decrease in the body weight and an increase in DAI， along with increased colon wet weight， shortened colon length， markedly elevated histopathological scores， and reduced expression of mucopolysaccharides and MUC2 （P＜0.01）. In contrast， no significant differences were observed in these parameters in the pseudo-germ-free model group （P＞0.05）. Compared to the conventional model group， the conventional QWD group showed significant improvement in all measured parameters， whereas the conventional mesalazine group showed reductions only in DAI scores and colon wet weight （P＜0.01）. No statistically significant differences were observed among the pseudo-germ-free model group， the pseudo-germ-free QWD group， and the pseudo-germ-free mesalazine group （P＞0.05）. ConclusionQWD may promote the reconstruction of the intestinal mucus barrier by regulating the intestinal flora， thereby exerting a therapeutic effect on acute UC.

ObjectiveTo explore the mechanisms of Qingchang Wenzhong Decoction （清肠温中方， QWD） in treating ulcerative colitis （UC）. MethodsA total of 100 male C57BL/6J mice were assigned to a pseudo-germ-free group （n=45） and a conventional group （n=55） using a random number table. Pseudo-germ-free model was established by giving antibiotic treatment and subsequently subjected to acute UC induction. After the model was successfully established， the 45 pseudo-germ-free acute UC mice were randomly allocated to a pseudo-germ-free model group， a pseudo-germ-free QWD group， and a pseudo-germ-free mesalazine group， with 15 mice in each group. The 55 conventional mice were randomly divided into a normal control group （n=10）， as well as a conventional model group， a conventional QWD group， and a conventional mesalazine group， with 15 mice in each group. Except for the normal control group， acute UC models were established in all other groups. Mice in the control group received no intervention. From day 32 of the experiment， mice in the pseudo-germ-free QWD group and the conventional QWD group were administered with QWD granules at a dose of 9.71 g/（kg·d） by gavage with deionized water， while those in the pseudo-germ-free mesalazine group and the conventional mesalazine group were given mesalazine enteric-coated tablets at a dose of 151.67 mg/（kg·d） by gavage. Mice in the remaining groups received an equal volume of deionized water once daily for 7 consecutive days. On day 25 of the experiment， six mice were randomly selected from both the pseudo-germ-free group and the conventional group to measure body weight， and fecal samples were collected for 16S rDNA sequencing to compare differences in gut microbiota， including operational taxonomic units （OTUs）， Shannon index， Observed_species index， and phylogenetic diversity （PD whole tree）. On day 39， body weight was measured in all groups， and the disease activity index （DAI） was evaluated. Colon length and colon wet weight were recorded. Histopathological changes in colonic tissues were assessed by hematoxylin and eosin （HE） staining， and histological injury scores were determined. In addition， the expression levels of mucopolysaccharides and mucin 2 （MUC2） in colonic tissues were measured. ResultsOn day 25， there was no significant difference in body weight between the pseudo-germ-free group and the conventional microbiota group （P＞0.05）. Compared to the conventional microbiota group， the pseudo-germ-free group showed significantly reduced OTUs， Shannon index， Observed_species index， and PD whole tree （P＜0.01）. On day 39， compared to the normal control group， mice in the conventional model group showed a significant decrease in the body weight and an increase in DAI， along with increased colon wet weight， shortened colon length， markedly elevated histopathological scores， and reduced expression of mucopolysaccharides and MUC2 （P＜0.01）. In contrast， no significant differences were observed in these parameters in the pseudo-germ-free model group （P＞0.05）. Compared to the conventional model group， the conventional QWD group showed significant improvement in all measured parameters， whereas the conventional mesalazine group showed reductions only in DAI scores and colon wet weight （P＜0.01）. No statistically significant differences were observed among the pseudo-germ-free model group， the pseudo-germ-free QWD group， and the pseudo-germ-free mesalazine group （P＞0.05）. ConclusionQWD may promote the reconstruction of the intestinal mucus barrier by regulating the intestinal flora， thereby exerting a therapeutic effect on acute UC.

Objective To analyze the clinical and epidemiological characteristics of influenza A(H3N2) in Tangshan City, Hebei Province, from 2023 to 2025, and to provide a scientific basis for precise prevention and control of local influenza. Methods The influenza-like cases and influenza outbreak cases in the influenza surveillance sentinel hospitals in Tangshan City from January 2023 to December 2025 were included in this study. The clinical characteristics and epidemic characteristics of H3N2 influenza patients were analyzed by descriptive epidemiological methods and chi-square test. Results A total of 11 567 influenza case samples were tested in the study, with a positive rate of 9.34% (1 080/11 567). Influenza A (H3N2) remained the predominant circulating subtype throughout the study period. January 2023 to February 2023 marked the tailing end of the previous season’s H3N2. Then, a minor peak dominated by H1N1 occurred from March to June, and H3N2 circulated again from October to December, peaking in December. From September 2024 to December 2024, H1N1 and H3N2 circulated concurrently, with H3N2 as the dominant strain, peaking in January of the following year. From March 2025 to September 2025, influenza activity remained at low level, and activity began to rise in October, with H1N1 peaking in November before declining, and H3N2 becoming the dominant strain in December. H3N2 mainly occurred in the 5-14 years old group. Cases in the 0–4-year-old group were primarily characterized by gastrointestinal symptoms, with high fever being common. Cases in the 5–59-year-old group were primarily characterized by systemic and respiratory symptoms, with better clinical outcomes. Cases aged 60 and older exhibited the highest rates of hospitalization, severe illness, and incidence of complications. Conclusion From 2023 to 2025, the influenza virus in Tangshan City, Hebei Province is dominated by influenza A (H3N2). The epidemic is characterized by a peak incidence during autumn and winter, co-circulation with H1N1, and fluctuations during the peak period. It is necessary to pay attention to the clinical management and prevention and control of influenza A (H3N2) in infants and the elderly.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To explore whether the biopsy rate and the positive rate of biopsy during colonoscopy can serve as effective indicators for evaluating the diagnostic proficiency of endoscopists.Methods Total fifteen endoscopists from the First Affiliated Hospital of Army Military Medical University,Guiqian International General Hospital and No.958 Hospital of PLA Army were enrolled and served as the study subjects.According to their years of experience,gender and working hours,they were divided into a senior group(n=8)and a junior group(n=7),a male group(n=9)and a female group(n=6),and a morning period(08:00-12:00)and an afternoon period(13:00-18:00).The data of all patients examined by the aforementioned endoscopists between January 2023 and December 2023 were collected,including the basic demographics,colonoscopic results,biopsy outcomes and pathological diagnoses of the patients.ANOVA was used to analyze the differences in the biopsy rate and positive rate of biopsy existed among the endoscopists of different years of experience,gender and working at different periods(morning and afternoon).Additionally,multivariate logistic regression analysis was employed to identify the independent risk factors associated with positive rates of biopsy.Results The senior group had significantly lower biopsy rate[(5.73±0.81)%vs(6.89±0.97)%],but obviously higher positive rate of biopsy[(53.52±3.87)%vs(33.70±7.85)%]than the junior group(both P<0.01).The biopsy rate was notably higher during the morning working time period than the afternoon working time period in all the endoscopits[(6.76±1.11)%vs(5.53±1.57)%,P<0.05].Logistic regression analysis showed that the years of experience[(53.52±3.87)%vs(33.70±7.85)%,OR=92.187,95%CI:3.118～2 725.366,P<0.01)and working time[(48.35±10.50)%vs(37.80±10.65)%,OR=20.885,95%CI:1.266～344.602,P<0.05)were influencing factors for positive rate of biopsy.Conclusion The biopsy rate is low and positive rate of biopsy is high among the senior experienced endoscopists,while,opposite results are seen in the junior experienced clinicians,indicating correlation of biopsy rate and positive rate of biopsy with diagnostic proficiency of endoscopists.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Objective:To summarize the clinicopathologic characteristics of malignant hypertension (MHT) patients with acute kidney injury (AKI) and application of renin-angiotensin-aldosterone system inhibitor (RAASi).Methods:It was a retrospective cohort study. The adult patients with MHT and AKI admitted to Peking University First Hospital from January 1, 2012 to July 14, 2022. The patients were categorized into RAASi group and non-RAASi group based on RAASi administration from AKI onset to discharge. The clinicopathological data between the two groups were compared, and application of RAASi was analyzed.Results:A total of 179 patients were enrolled with age of 31 (26, 37) years and 148 males (82.7%). Ninety-five patients (53.1%) received dialysis treatment. The common causes of MHT were essential hypertension (125 patients, 69.8%), renal hypertension (39 patients, 21.8%) and endocrine hypertension (7 patients, 3.9%). AKI severity distribution showed 41 patients (22.9%) in stage 1, 1 patient (0.5%) in stage 2 and 137 patients (76.5%) in stage 3. Among MHT patients, 94 patients (52.5%) had been treated with RAASi before AKI, and 13 patients (7.3%) discontinued RAASi after AKI. Among 85 patients (47.5%) without receiving RAASi treatment before AKI, 68 new patients (38.0%) received RAASi treatment after AKI, and 40 patients (22.3%) were treated with the support of dialysis. Compared with non-RAASI group ( n=30), proportions of chronic kidney disease ( χ2=6.324, P=0.012) and post-AKI hyperkalemia ( χ2=4.048, P=0.044) in RAASi group ( n=149) were lower, and the proportion of dialysis treatment ( χ2=5.638, P=0.018), admission diastolic blood pressure ( Z=-3.609, P<0.001) and maximum diastolic blood pressure during hospitalization ( Z=-1.978, P=0.048) were higher. There were no statistically significant differences in the rates of target blood pressure control and renal function recovery between the two groups during hospitalization (all P>0.05). During hospitalization, 64 patients received renal biopsies, of which 50 patients (78.1%) had typical MHT vascular lesions such as "onion skin" in renal arterioles. Twenty-seven patients (42.2%) were complicated with glomerular diseases, and IgA nephropathy was the most common type (85.2%, 23/27). The proportions of glomerular ischemia and sclerosis, endothelial cell proliferation and acute renal tubular injury in RAASi group ( n=54) were lower than those in non-RAASi group ( n=10), and proportions of thrombosis and "onion skin" change were higher than those in RAASi group ( n=10), but the differences were not statistically significant (all P>0.05). Renal function recovery occurred in 47 patients (26.3%) by discharge. Among 95 dialysis patients, 26 patients (27.4%) achieved dialysis independence at discharge. Conclusions:MHT patients with AKI exhibit severe renal pathology and short-term poor prognosis. RAASi is primarily prescribed to those with relatively better kidney function or those receiving dialysis support.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.