Meiotic recombination is a core molecular event that generates genetic diversity in sexually reproducing organisms, and is of great significance for both genome evolution and proper chromosome segregation. Meiotic recombination occurs in two forms: crossover (CO) and non-crossover (NCO). Although NCO events are far more abundant than CO events, they have been difficult to detect. Consequently, previous research has largely focused on CO, leaving the characteristics and functional roles of NCO poorly understood. A recent study published in Nature used large-scale family-based whole-genome sequencing data to construct a high-resolution recombination map. This map revealed the mutational features induced by NCO—the dominant form of recombination—along with their sex-specific differences, and quantified, for the first time, the contribution of NCOs to de novo mutations and age-related effects, representing an important milestone in the field of meiotic recombination. Specifically, compared with paternal NCOs, maternal NCOs are fewer in number but span longer regions; they accumulate continuously with increasing maternal age and occur largely outside programmed recombination hotspots. NCOs also represent a major source of de novo mutations, with approximately 11% of maternal de novo mutations being attributable to NCOs. This study not only provides a high-resolution map of human meiotic recombination as a resource for future research, but also offers, for the first time, a genome‑wide perspective on the contribution of meiotic NCO recombination to genetic diversity.

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 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.

Objective:To investigate lymph node metastasis(LNM)in the prostatic anterior fat pad(PAFP)of PCa patients after robot-assisted radical prostatectomy(RARP),and analyze the clinicopathological features and prognosis of LNM in the PAFP.Methods:We retrospectively analyzed the clinicopathological data on 1 003 cases of PCa treated by RARP in the Department of Urolo-gy of PLA General Hospital from January 2017 to December 2022.All the patients underwent routine removal of the PAFP during RARP and pathological examination,with the results of all the specimens examined and reported by pathologists.Based on the pres-ence and locations of LNM,we grouped the patients for statistical analysis,compared the clinicopathological features between different groups using the Student's t,Mann-Whitney U and Chi-square tests,and conducted survival analyses using the Kaplan-Meier and Log-rank methods and survival curves generated by Rstudio.Results:Lymph nodes were detected in 77(7.7％)of the 1 003 PAFP samples,and LNM in 11(14.3％)of the 77 cases,with a positive rate of 1.1％(11/1 003).Of the 11 positive cases,9 were found in the upgraded pathological N stage,and the other 2 complicated by pelvic LNM.The patients with postoperative pathological stage≥T3 constituted a significantly higher proportion in the PAFP LNM than in the non-PAFP LNM group(81.8％[9/11]vs 36.2％[359/992],P=0.005),and so did the cases with Gleason score ≥8(87.5％[7/8]vs 35.5％[279/786],P=0.009).No statisti-cally significant differences were observed in the clinicopathological features and biochemical recurrence-free survival between the pa-tients with PAFP LNM only and those with pelvic LNM only.Conclusion:The PAFP is a potential route to LNM,and patients with LNM in the PAFP are characterized by poor pathological features.There is no statistically significant difference in biochemical recur-rence-free survival between the patients with PAFP LNM only and those with pelvic LNM only.Routine removal of the PAFP and inde-pendent pathological examination of the specimen during RARP is of great clinical significance.

[Purpose]To analyze the compliance and its influencing factors of lung cancer screening using low-dose computed tomography(LDCT)among high-risk population in urban districts of Chongqing from 2013 to 2021.[Methods]The lung cancer screeing of Cancer Early Diagnosis and Treatment Project was conducted among permanent residents aged 40～69 years old from 14 urban districts of Chongqing selected by cluster sampling method from 2013 to 2021.The questionnaire survey was performed to assess the risk level of lung cancer,and individuals with high risk were advised to have LDCT examination.The compliance rate of LDCT examination among high-risk populations was calculated and compared using Chi-square test among residents with different de-mographic features;the influencing factors of compliance was analyzed with generalized linear mixed models.[Results]A total of 316 066 residents completed the risk assessment questionnaire survey,52 858 people were assessed as high-risk(17.17％).Among the high-risk population,20 398 completed LDCT screening,with an overall compliance rate of 38.59％.The generalized linear mixed model showed that male participants(OR=0.871,95％CI:0.823～0.922)and smokers(light smokers:OR=0.829,95％CI:0.775～0.886;heavy smokers:OR=0.842,95％CI:0.792～0.896)had lower compliance rates;while people with higher education level(OR=1.347,95％CI:1.265～1.435),occupational exposure to harmful substances(OR=1.400,95％CI:1.340～1.463),passive smoking for 20 years or more(OR=1.472,95％CI:1.376～1.576),infrequent physical exercise(OR=1.203,95％CI:1.152～1.256),family history of lung cancer(OR=2.312,95％CI:2.201～2.429),and those having media promotion by community staff(OR=1.365,95％CI:1.223～1.524),and trained community staff(OR=1.343,95％CI:1.227～1.470)had higher compliance rates.Comorbidities were also factors influencing compliance,and there was an increasing trend of compliance rate with the increase of comorbidity numbers(P＜0.001).[Conclusion]The compli-ance rate of LDCT examination for lung cancer screening in Chongqing needs to be improved,and more precise health education should be implemented for groups with different characteristics to improve the compliance among high-risk population.

[Purpose]To analyze the results of breast cancer screening among women aged 45～74 in Chongqing from 2012 to 2022 and compare the risk of breast cancer among women with differ-ent characteristics.[Methods]The Urban Cancer Early Diagnosis and Treatment Program was con-ducted in Chongqing from 2012 to 2022,female residents aged 45～74 years old participated in breast cancer screening.The participants who were assessed as at high risk of breast cancer in the preliminary screening were advised to receive ultrasonography and mammography examination in designated hospitals.The study population was followed up annually to obtain information on their health outcomes.The high risk rate of breast cancer,compliance of further examination,the inci-dence density and breast cancer risk were calculated.[Results]A total of 207 891 women com-pleted the questionnaires survey and risk assessment,and 35 947 were assessed as the individuals with high risk of breast cancer with a high risk rate of 17.29％.Among them 14 713 received the imaging screening with a compliance rate of 40.93％.After a mean follow-up of(5.43±3.01)years,847 cases of breast cancer were diagnosed with a cumulative incidence rate of 407.43/105,an in-cidence density of 75.03/105 person-years(95％CI:70.15/105～80.26/105 person-years).Cox pro-portional hazards regression showed that the risk of breast cancer was higher in obese women than that in normal weight women(HR=1.26,95％CI:1.00～1.59);the risk of breast cancer was signifi-cantly higher in those with family history of breast cancer than that in those without family history(HR=1.69,95％CI:1.36～2.09).Compared with non-high-risk groups of breast cancer,the risk of breast cancer was increased in high-risk individuals who were screened or not screened(HR=1.36,95％CI:1.06～1.73 and HR=1.26,95％CI:1.01～1.56).[Conclusion]The breast cancer screening program combining primary risk assessment with ultrasonography and mammography for the high-risk groups can improve the detection rate,and the compliance rate of imaging screening need to be improved in the future and make accurate screening for people with high risk of breast cancer.

[Purpose]To analyze the compliance and its influencing factors of lung cancer screening using low-dose computed tomography(LDCT)among high-risk population in urban districts of Chongqing from 2013 to 2021.[Methods]The lung cancer screeing of Cancer Early Diagnosis and Treatment Project was conducted among permanent residents aged 40～69 years old from 14 urban districts of Chongqing selected by cluster sampling method from 2013 to 2021.The questionnaire survey was performed to assess the risk level of lung cancer,and individuals with high risk were advised to have LDCT examination.The compliance rate of LDCT examination among high-risk populations was calculated and compared using Chi-square test among residents with different de-mographic features;the influencing factors of compliance was analyzed with generalized linear mixed models.[Results]A total of 316 066 residents completed the risk assessment questionnaire survey,52 858 people were assessed as high-risk(17.17％).Among the high-risk population,20 398 completed LDCT screening,with an overall compliance rate of 38.59％.The generalized linear mixed model showed that male participants(OR=0.871,95％CI:0.823～0.922)and smokers(light smokers:OR=0.829,95％CI:0.775～0.886;heavy smokers:OR=0.842,95％CI:0.792～0.896)had lower compliance rates;while people with higher education level(OR=1.347,95％CI:1.265～1.435),occupational exposure to harmful substances(OR=1.400,95％CI:1.340～1.463),passive smoking for 20 years or more(OR=1.472,95％CI:1.376～1.576),infrequent physical exercise(OR=1.203,95％CI:1.152～1.256),family history of lung cancer(OR=2.312,95％CI:2.201～2.429),and those having media promotion by community staff(OR=1.365,95％CI:1.223～1.524),and trained community staff(OR=1.343,95％CI:1.227～1.470)had higher compliance rates.Comorbidities were also factors influencing compliance,and there was an increasing trend of compliance rate with the increase of comorbidity numbers(P＜0.001).[Conclusion]The compli-ance rate of LDCT examination for lung cancer screening in Chongqing needs to be improved,and more precise health education should be implemented for groups with different characteristics to improve the compliance among high-risk population.

[Purpose]To analyze the results of breast cancer screening among women aged 45～74 in Chongqing from 2012 to 2022 and compare the risk of breast cancer among women with differ-ent characteristics.[Methods]The Urban Cancer Early Diagnosis and Treatment Program was con-ducted in Chongqing from 2012 to 2022,female residents aged 45～74 years old participated in breast cancer screening.The participants who were assessed as at high risk of breast cancer in the preliminary screening were advised to receive ultrasonography and mammography examination in designated hospitals.The study population was followed up annually to obtain information on their health outcomes.The high risk rate of breast cancer,compliance of further examination,the inci-dence density and breast cancer risk were calculated.[Results]A total of 207 891 women com-pleted the questionnaires survey and risk assessment,and 35 947 were assessed as the individuals with high risk of breast cancer with a high risk rate of 17.29％.Among them 14 713 received the imaging screening with a compliance rate of 40.93％.After a mean follow-up of(5.43±3.01)years,847 cases of breast cancer were diagnosed with a cumulative incidence rate of 407.43/105,an in-cidence density of 75.03/105 person-years(95％CI:70.15/105～80.26/105 person-years).Cox pro-portional hazards regression showed that the risk of breast cancer was higher in obese women than that in normal weight women(HR=1.26,95％CI:1.00～1.59);the risk of breast cancer was signifi-cantly higher in those with family history of breast cancer than that in those without family history(HR=1.69,95％CI:1.36～2.09).Compared with non-high-risk groups of breast cancer,the risk of breast cancer was increased in high-risk individuals who were screened or not screened(HR=1.36,95％CI:1.06～1.73 and HR=1.26,95％CI:1.01～1.56).[Conclusion]The breast cancer screening program combining primary risk assessment with ultrasonography and mammography for the high-risk groups can improve the detection rate,and the compliance rate of imaging screening need to be improved in the future and make accurate screening for people with high risk of breast cancer.

Objective To investigate the clinical characteristics of patients with clinical and subclinical Cushing's syndrome caused by primary bilateral macronodular adrenal hyperplasia(PBMAH).Methods A retrospective analysis was performed on the clinical data of 198 patients with Cushing's syndrome caused by PBMAH diagnosed in the First Medical Center of Chinese PLA General Hospital from January 2004 to October 2024.According to clinical manifestations,the patients were classified into clinical type Cushing's syndrome(n=61)and subclinical type Cushing's syndrome(n=137),and the clinical characteristics of the two types were compared.Results The mean age at diagnosis of patients with PBMAH-induced Cushing's syndrome was(53.5±10.4)years,including 118 males and 80 females,with a male-to-female ratio of 1.475:1.Compared with the subclinical type,the clinical type had a higher proportion of females,higher levels of serum cortisol,24-hour urine free cortisol(24 h UFC),and inhibited serum cortisol after low-dose dexamethasone suppression.Additionally,the clinical type had lower plasma ACTH,larger adrenal nodules and a higher risk of surgery(P<0.05)compared with those in subclinical type.The incidences of hypertension,dyslipidemia,obesity,diabetes mellitus,hypokalemia,vitamin D deficiency,osteoporosis,coronary heart disease,and cerebrovascular disease in patients with Cushing's syndrome caused by PBMAH were 87.9%,50.5%,37.1%,36.9%,27.8%,25.9%,18.7%,18.7%and 12.1%,respectively.Among them,compared with subclinical type patients,clinical type patients had higher incidence of hypokalaemia,vitamin D deficiency and osteoporosis(P<0.05),while there were no statistically significant differences in the incidences of other comorbidities between the two types(P>0.05).The results of postoperative follow-up for PBMAH patients showed that the short-term biochemical remission rate of unilateral total adrenalectomy was 41.5%(22/53)and the long-term biochemical remission rate was 32.0%(8/25).The short-term biochemical remission rate of unilateral partial(or nodular)adrenalectomy was 52.9%(9/17),and the long-term biochemical remission rate was 14.3%(1/7).All patients who underwent unilateral total adrenalectomy plus contralateral partial resection developed adrenal insufficiency(3/3),and 1 patient(1/3)relapsed 3.4 years after surgery.Conclusion Clinical and subclinical types of Cushing's syndrome caused by PBMAH have their distinct clinical characteristics.Surgery is an effective treatment for PBMAH,but a certain proportion of patients fail to achieve biochemical remission after non-bilateral total adrenalectomy.