1.Research Pogress on Action Mechanism of NLRP3 Inflammasome and Pyroptosis in Diabetic Nephropathy
Zhenyun LEI ; Guozhong XUE ; Zhenhua LIU ; Xinli ZHANG
Medical Journal of Peking Union Medical College Hospital 2025;16(3):722-729
Diabetic nephropathy (DN), as one of the most common complications of diabetes, is a primary cause of end-stage renal disease. The pathogenesis of DN encompasses processes such as chronic inflammation, recruitment and activation of immune cells, tubular and glomerular injury, and renal fibrosis. These processes are highly correlated with the activation of the nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 (NLRP3) inflammasome and the resulting pyroptosis it mediates. Previous studies have shown that the release of pro-inflammatory cytokines, leakage of damage-associated molecular patterns (DAMPs), recruitment and activation of immune cells can be reduced by regulating the NLRP3 inflammasome and its mediated pyroptosis, thereby slowing the diffusion of inflammatory responses in adjacentcells, fibrosis, and tissue remodeling processes. Ultimately, these process can improve renal injury and dysfunction caused by diabetic nephropathy. This article summarizes the molecular regulatory mechanisms of the NLRP3 inflammasome and its mediated pyroptosis at different pathological stages of DN, proposes potential targets for regulating their activation, aiming to provide a new direction for personalized treatment of DN.
2.Clinical observation of free palmaris longus tendon graft reconstruction in treatment of gouty tophus erosion lesions in flexor tendon of wrist and hand.
Guozhong WANG ; Chao LU ; Zhigang QU ; Yuejuan ZHANG ; Benjun BI ; Fei GAO ; Zhao ZHANG ; Yuehai PAN ; Enxia ZHU ; Heng HUANG
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(3):278-283
OBJECTIVE:
To investigate the effectiveness of free palmaris longus tendon graft reconstruction in the treatment of gouty tophus erosion lesions in flexor tendon of wrist and hand.
METHODS:
A retrospective analysis was conducted on 8 patients with gouty tophus erosion lesions in flexor tendon of wrist and hand who underwent free palmaris longus tendon graft reconstruction between June 2017 and December 2023. All patients were male, aged 22-65 years, with an average of 45.9 years. The duration of gout history ranged from 2 to 18 years, with an average of 8.8 years. The duration from the discovery of gouty tophus to operation ranged from 12 to 26 months, with an average of 17.6 months. The gouty tophus eroded the flexor pollicis longus tendon in 4 cases, with Verdan flexor tendon zones being Ⅰ-Ⅱ in 1 case and Ⅳ-Ⅴ in 3 cases. The flexor digitorum profundus tendons were affected in 2 cases for the index finger, 1 for the middle finger, and 1 for the ring finger, all located in zone Ⅳ-Ⅴ. The long axis of the gouty tophus ranged from 2.3 to 4.5 cm, with an average of 3.4 cm. All 8 patients presented with limited finger flexion and extension. Among them, 4 cases were accompanied by median nerve compression symptoms, and 1 case had associated bone and joint destruction in the hand. The total active motion (TAM) of the affected finger was (81.3±30.2)° before operation according to the hand function evaluation criteria for tendon repair by the Chinese Society of Hand Surgery of the Chinese Medical Association, and the functional evaluation was poor. The harvested palmaris longus tendon intraoperatively was 7-9 cm in length.
RESULTS:
Surgical incisions in all 8 patients healed by first intention, with no infections, graft non-union, or significant adhesion complications. All patients were followed up 8-25 months, with an average of 14.8 months. Numbness symptoms resolved in all 4 patients who presented with median nerve compression symptoms. Patients did not experience wrist pain or other discomfort, and function was not compromised. At last follow-up, according to the hand function evaluation criteria for tendon repair by the Chinese Society of Hand Surgery of the Chinese Medical Association, the TAM of 8 patients was (197.5±55.8)°, which significantly improved when compared with that before operation ( t=11.638, P<0.001); the hand function of 1 patient with gouty tophus in zone Ⅰ-Ⅱ flexor pollicis longus tendon was good, and the other 7 patients were excellent.
CONCLUSION
Free palmaris longus tendon graft reconstruction demonstrates good effectiveness in treating gouty tophus erosion lesions in flexor tendon of wrist and hand.
Humans
;
Middle Aged
;
Male
;
Adult
;
Tendons/surgery*
;
Retrospective Studies
;
Aged
;
Gout/complications*
;
Wrist/surgery*
;
Plastic Surgery Procedures/methods*
;
Hand/surgery*
;
Treatment Outcome
;
Young Adult
3.Multi-segment inverted Y-shaped vein transplantation using anterior lateral malleolar venous network for repair of amputated palm injury distal to superficial palmar arch.
Zhao ZHANG ; Yanyan WANG ; Fei GAO ; Yuehai PAN ; Heng HUANG ; Chao LU ; Guozhong WANG ; Zhigang QU ; Benjun BI
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(5):628-632
OBJECTIVE:
To explore the effectiveness of multi-segment inverted Y-shaped vein transplantation using the anterior lateral malleolar venous network for repair of amputated palm injury distal to the superficial palmar arch.
METHODS:
Between September 2018 and July 2023, 5 patients with amputated palm injury distal to the superficial palmar arch were treated. There were 3 males and 2 females with an average age of 35.4 years (range, 29-52 years). The time from injury to admission was 1-6 hours (mean, 3.2 hours). The multi-segment inverted Y-shaped vein transplantation in the anterior lateral malleolar venous network were used to repair the common and proper palmar digital arteries; the another anterior lateral malleolar venous network was used to repair the dorsal vein of the hand. The soft tissue defect of dorsal hand in 1 patient was repaired with the pedicled ilioinguinal flap, and the wound at the donor site was directly sutured. Postoperative treatment included anti-infection therapy, antispasmodic therapy, and thrombosis prevention measures.
RESULTS:
The partial necrosis of the fingertip of the thumb occurred in 1 case, and the marginal necrosis of the abdominal flap after operation occurred in 1 case. The remaining fingers showed good blood supply with normal tension. The incision at donor site of the abdominal flap healed by first intention. All patients were followed up 8-41 months (median, 19 months). At last follow-up, the hand contour was satisfactory; the grasping function, opposition function, and proprioception recovered, and two-point discrimination ranged from 5 to 7 mm (mean, 6 mm). According to the upper extremity function evaluation criteria issued by Hand Surgery Society of the Chinese Medical Association, the functional outcomes were excellent in 3 cases, good in 1 case, and fair in 1 case.
CONCLUSION
The multi-segment inverted Y-shaped vein transplantation using the anterior lateral malleolar venous network for repairing defects in the common and proper palmar digital arteries distal to the superficial palmar arch offers advantages such as superficial location, flexible harvesting, and high compatibility. This technique has demonstrated favorable outcomes in complex transmetacarpal amputation reconstruction.
Humans
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Adult
;
Male
;
Female
;
Hand Injuries/surgery*
;
Middle Aged
;
Plastic Surgery Procedures/methods*
;
Veins/transplantation*
;
Surgical Flaps/blood supply*
;
Hand/surgery*
;
Treatment Outcome
;
Soft Tissue Injuries/surgery*
4.Application of soft tissue balance combined with medial displacement calcaneal osteotomy for progressive collapsing foot deformity.
Guozhong YE ; Haiquan MAI ; Liu ZHANG ; Boyuan SU ; Guanglong ZENG ; Haobo HUANG
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(12):1556-1561
OBJECTIVE:
To explore the effectiveness of the flexor digitorum longus (FDL) transfer combined with single-bundle spring ligament reconstruction and medial displacement calcaneal osteotomy in the treatment of stage ⅠAB progressive collapsing foot deformity (PCFD).
METHODS:
Between January 2019 and September 2023, 19 patients (19 feet) with stage ⅠAB PCFD were treated with FDL transfer combined with single-bundle spring ligament reconstruction and medial displacement calcaneal osteotomy. There were 11 males and 8 females, aged 18 to 60 years, with an average age of 45.5 years. Nine cases were on the left foot and 10 cases on the right foot. The disease duration was 9-21 months, with an average of 12.3 months. Postoperatively, the effectiveness was evaluated by visual analogue scale (VAS) for pain, American Orthopaedic Foot and Ankle Society (AOFAS) score, and Tegner score. Based on X-ray films, the talonavicular coverage angle (TNCA), talus-first metatarsal angle (T1MT), Meary angle, and pitch angle were measured. The plantar pressure parameters of the foot were measured by the Footscan plantar pressure measurement system, including peak pressure and load of the forefoot, midfoot, and hind foot. The patients' satisfaction with the surgical outcome was evaluated.
RESULTS:
All 19 surgeries were successfully completed. One patient had poor incision healing after operation, while the incisions of the remaining patients healed by first intention. All patients were followed up 12-28 months (mean, 16.8 months). At last follow-up, the VAS score significantly decreased compared with that before operation, and the AOFAS score and Tegner score significantly increased ( P<0.05). Radiological measurements showed that the TNCA, T1MT, Meary angle, and Pitch angle all significantly improved compared with those before operation ( P<0.05). Plantar pressure tests indicated that the peak pressures of the forefoot and midfoot significantly reduced compared with those before operation ( P<0.05), while the peak pressure of the hind foot showed no significant change ( P>0.05). The forefoot load significantly increased and the midfoot load decreased compared with those before operation ( P<0.05), while the hind foot load showed no significant change ( P>0.05). The total satisfaction rate of patients with the surgical outcome (very satisfied+satisfied) reached 84.2% (16/19).
CONCLUSION
The FDL transfer combined with single-bundle spring ligament reconstruction and medial displacement calcaneal osteotomy can effectively correct the stage ⅠAB PCFD, improve the abnormal distribution of plantar pressure and load, alleviate foot pain symptoms, and improve foot movement function. The patient's satisfaction is high. However, the long-term effectiveness still needs to be further observed and clarified.
Humans
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Female
;
Male
;
Osteotomy/methods*
;
Adult
;
Middle Aged
;
Calcaneus/surgery*
;
Young Adult
;
Adolescent
;
Tendon Transfer/methods*
;
Treatment Outcome
;
Plastic Surgery Procedures/methods*
;
Foot Deformities/surgery*
;
Ligaments, Articular/surgery*
5.Significance of precise classification of sacral meningeal cysts by multiple dimensions radiographic reconstruction MRI in guiding operative strategy and rehabilitation.
Jianjun SUN ; Qianquan MA ; Xiaoliang YIN ; Chenlong YANG ; Jia ZHANG ; Suhua CHEN ; Chao WU ; Jingcheng XIE ; Yunfeng HAN ; Guozhong LIN ; Yu SI ; Jun YANG ; Haibo WU ; Qiang ZHAO
Journal of Peking University(Health Sciences) 2025;57(2):303-308
OBJECTIVE:
To precise classify sacral meningeal cysts, effective guide minimally invasive neurosurgery and postoperative personalized rehabilitation by multiple dimensions radiographic reconstruction MRI.
METHODS:
From March to December 2021, based on the original 3D-fast imaging employing steadystate acquisition (FIESTA) scanning sequence, 92 patients with sacral meningeal cysts were pre-operatively evaluated by multiple dimensional reconstruction MRI. The shape of nerve root and the leakage of cyst were reconstructed according to the direction of nerve root or leakage track showed on original MRI scans. Sacral canal cysts were accurately classified as including nerve root and without nerve root, so as to accurately design the incision of skin and formulate corresponding open range of the posterior wall of the sacral canal. Under the microscope intraoperation, the shape of the nerve roots inside cysts or leakage track of the cysts without nerve roots were verified and explored. After the reinforcement and shaping operation, several reexaminations of multiple dimensional reconstruction MRI were performed to understand the deformation of the nerve root and hydrops in the operation cavity, so as to formulate a persona-lized rehabilitation plan for the patients.
RESULTS:
Among the 92 patients with sacral mengingeal cyst, 58 (63.0%) cysts with nerve root cyst, 29 (31.5%) cysts without nerve root cyst, and 5 (5.4%) cysts with mixed sacral canal cyst. In 58 patients with nerve root cysts, the accuracy of preoperative clinical classification on MRI image reached 96.6% (56/58) through confirmation by operating microscope. Only 2 cases of large single cyst with nerve root on the head of cyst were mistaken for without nerve root type. In 29 patients with sacral cyst without nerve root, the accuracy of preoperative image reached 100% through confirmation by operating microscope. The accuracy of judging the internal nerve root and leakage of 12 cases with recurrent sacral cyst was also 100%. Two cases of delayed postoperative hydrops were found one month after operation. After rehabilitation treatment by moxibustion and bathing, the hydrops disappeared 4-6 months after operation.
CONCLUSION
Multiple dimensional reconstruction MRI can precisely make clinical classification of sacral meningeal cysts before operation, guide minimally invasive neurosurgery effectively, and improve the rehabilitation effect.
Humans
;
Magnetic Resonance Imaging/methods*
;
Male
;
Female
;
Sacrum/surgery*
;
Adult
;
Middle Aged
;
Imaging, Three-Dimensional/methods*
;
Cysts/rehabilitation*
;
Aged
;
Adolescent
;
Young Adult
;
Spinal Nerve Roots/diagnostic imaging*
;
Minimally Invasive Surgical Procedures
;
Neurosurgical Procedures/methods*
6.Fastest recovery after surgery during perioperative period under laparoscopic surgery of gastrointestinal tumors
Qizhi LIU ; Huimin ZHOU ; Minjun ZHOU ; Guozhong CHEN ; Cheng LI ; Junyi CHEN ; Yonggang HONG ; Nan ZHANG ; Hanrong LIU ; Xiaohuang TU
Academic Journal of Naval Medical University 2025;46(1):135-140
Objective To explore the feasibility and safety of fastest recovery after surgery(FRAS)in laparoscopic surgery of gastrointestinal tumors.Methods The clinical data of patients undergoing laparoscopic surgery for gastrointestinal tumors under FRAS and enhanced recovery after surgery(ERAS)from Jan.2023 to May 2024 were collected,and perioperative safety and medical cost were analyzed.Results A total of 87 patients were enrolled,including 43 in the FRAS group and 44 in the ERAS group.Compared with the ERAS group,the FRAS group had significantly shorter surgical time(3.0[2.5,3.5]h vs 3.0[2.5,4.0]h),first postoperative movement time([2.85±4.29]h vs[20.18±6.13]h),first postoperative oral feeding time(2.0[2.0,3.0]h vs 24.0[15.0,48.0]h),postoperative hospital stay(24.0[20.0,40.0]h vs 192.0[150.0,216.0]h),lower hospitalization costs(50 515.61[46 650.44,56 827.12]yuan vs 65 555.09[58 683.21,86 239.02]yuan),and lower medication costs(2 671.09[2 063.31,3 127.09]yuan vs 7 326.90[5 104.66,10 674.26]yuan)(all P<0.05).Conclusion It is safe and feasible to use FRAS during the perioperative period of laparoscopic radical gastrectomy for gastrointestinal tumors,and FRAS can also reduce the costs of hospitalization and medications.
7.Clinical Efficacy of Tendon-Regulating and Bone-Setting Manipulation Combined with Subtalar Joint Arthroereisis in the Treatment of Adolescent Flexible Flatfoot
Haiquan MAI ; Guozhong YE ; Boyuan SU ; Liu ZHANG ; Zhitao HUANG ; Xiaohan LIANG ; Guanglong ZENG
Journal of Guangzhou University of Traditional Chinese Medicine 2025;42(11):2789-2797
Objective To evaluate the clinical efficacy of tendon-regulating and bone-setting manipulation combined with subtalar joint arthroereisis in the treatment of adolescent flexible flatfoot.Methods A retrospective analysis was conducted on the clinical data of 86 children with flexible flatfoot treated at Dongguan Hospital of Guangzhou University of Chinese Medicine(Dongguan Traditional Chinese Medicine Hospital)between December 2022 and February 2024.Based on pre-treatment physician-patient communication,the children were divided into an trial group(44 cases)and a control group(42 cases).The control group received subtalar joint arthroereisis alone,while the trial group received additional tendon-regulating and bone-setting manipulation just once one day before surgery and once weekly postoperatively for one month,with a follow-up period of no less than 6 months.The Visual Analogue Scale(VAS)pain score,American Orthopaedic Foot & Ankle Society(AOFAS)ankle-hindfoot score,Tegner activity score,radiographic parameters,and static plantar pressure parameters of the two groups were observed before and after surgery.Results(1)Regarding clinical data,all surgeries were successfully completed in both groups.There were no statistically significant differences in perioperative general data,including operative time,hospital stays,and complication rates(P>0.05).All children were followed up for no less than 6 months.The results showed that at the final follow-up,the VAS pain score,AOFAS ankle-hindfoot score,and Tegner activity score were significantly improved in both groups compared to preoperative values(P<0.05),and the improvement in the trial group was significantly greater than that in the control group(P<0.05 or P<0.01).(2)Regarding radiographic parameters,at the final follow-up,the talonavicular coverage angle(TNCA),talus-first metatarsal angle(T1MT),talus-second metatarsal angle(T2MT)on weight-bearing anteroposterior radiographs,and the Meary angle between the talus and the first metatarsal as well as calcaneal Pitch angle(Pitch angle)on weight-bearing lateral radiographs were significantly improved in both groups compared to preoperative values(P<0.05).The improvement in Meary angle,T1MT angle,and T2MT angle in the trial group was significantly greater than that in the control group(P<0.01).However,there were no statistically significant differences in TNCA and Pitch angle between the two groups at the final follow-up(P>0.05).(3)Regarding plantar pressure testing,at the 1-month postoperative follow-up,the forefoot load increased significantly in both groups compared to preoperative values(P<0.05),while the midfoot load significantly decreased(P<0.05).The increase in forefoot load and decrease in midfoot load in the trial group were significantly greater than those in the control group(P<0.05 or P<0.01).However,there were no statistically significant differences in hindfoot load between preoperative and postoperative values or between the two groups at the 1-month follow-up(P>0.05).Conclusion For adolescent flexible flatfoot,tendon-regulating and bone-setting manipulation combined with subtalar joint arthroereisis can effectively restore the arch,improve foot mechanical imbalance,thereby correcting flatfoot deformity and enhancing joint motor function.
8.Comparative analysis of emergency service capabilities in county-level hospitals in Zhejiang and Jiangsu Provinces
Yi YANG ; Zeng HUANG ; Silong ZHANG ; Xiafei ZHOU ; Zilong LI ; Yuefeng MA ; Guozhong CHEN ; Hengjin DONG
Chinese Journal of Emergency Medicine 2025;34(5):744-750
Objective:To analyze the differences in emergency rescue service capacities between county-level hospitals in Zhejiang and Jiangsu provinces, and propose targeted improvement suggestions.Methods:Cluster sampling was employed, with representative county-level hospitals recommended by provincial hospital alliances in Zhejiang and Jiangsu. Emergency departments voluntarily submitted data, resulting in 24 hospitals from Zhejiang and 34 from Jiangsu. Data were collected through the China County-Level Hospital Emergency Service Capability Evaluation System. Differences between provinces were analyzed. Spearman correlation analysis explored relationships between multidimensional indicators, and multivariate logistic regression identified factors influencing hospital grade B++ and above.Results:In terms of department scale, Jiangsu had a larger emergency department area (4 853 m 2vs. 1 927 m 2, P<0.001), more beds of comprehensive inpatient wards in the emergency department (25.5 beds vs. 5.5 beds, P=0.011), and higher scores for the ratio of emergency department area to beds (4.8 vs. 3.4, P=0.005) than Zhejiang. In terms of staffing, Jiangsu had a higher proportion of doctors with master's degrees or above (13.8% vs. 0.0%, P<0.001), a higher proportion of frontline emergency medical staff with over three years of clinical experience (100.0% vs. 91.5%, P=0.001), and more doctors (19 vs. 15, P=0.039) and nurses (46 vs. 32, P=0.039). In terms of quality and safety and medical service capacity, Zhejiang had a higher severe trauma resuscitation success rate (92.9% vs. 83.75%, P=0.003), annual emergency surgery volume (1 002 vs. 428, P=0.015), and number of emergency surgery procedures (125 vs. 42, P=0.027), but Jiangsu had a shorter emergency room stay time (87.5 min vs. 136.2 min, P=0.029). In terms of informatization, Zhejiang outperformed Jiangsu in all indicators, especially in patient information interconnection and sharing (100.0% vs. 82.4%, P=0.030) and in-hospital diagnosis and treatment timeline (91.7% vs. 73.5%, P=0.043). Correlation analysis showed that the total specialty scale score was significantly positively correlated with the in-hospital emergency rescue service capacity score ( r=0.576) and the staffing score ( r=0.455). The total evaluation score was significantly positively correlated with the informatization total score ( r=0.397) and the pre-hospital emergency rescue service capacity score ( r=0.322). Binary Logistic regression analysis showed that the emergency rescue service capacity score was significantly positively correlated with hospital grade ( B=1.431, P=0.03, OR=4.185, 95% CI:1.152-15.205). For every 1-unit increase in the emergency department area ( B=0.002, P=0.05), the probability of a hospital being upgraded to B++ or above increased by 0.2% ( OR=1.002, 95% CI:1.000-1.004). Conclusions:Both provinces exhibit distinct advantages in emergency department development. Departmental scale and configuration significantly impact emergency service capabilities, while staffing and quality management constitute core elements for improvement. Informatization construction notably enhances emergency service efficiency and quality.
9.Epidemiological Characteristics and Spatial Distribution of Pulmonary Tuberculosis in Lanping County from 2018 to 2023
Furong ZHANG ; Yidan YU ; Jiarui ZHANG ; Xiujun LUO ; Xinyue LI ; Qi DENG ; Zhong SUN ; Guozhong HE
Journal of Kunming Medical University 2025;46(6):20-28
Objective To investigate the epidemiological trends,temporal and spatial distribution characteristics of pulmonary tuberculosis in Lanping County.Methods Based on tuberculosis management data and basic information systems from the"China Disease Prevention and Control Information System,"pulmonary tuberculosis data from Lanping County for 2018-2023 were obtained.Descriptive epidemiology,concentration method,circular distribution method,and spatial autocorrelation analysis were used to conduct epidemiological and spatial analyses of the pulmonary tuberculosis data.Results A total of 2836 TB cases were reported in Lanping County from 2018 to 2023,with an average annual incidence rate of 233.26 per 100000,showing a declining trend.The male-to-female ratio was 1.95∶1,with the highest incidence among individuals aged 60 and above(932 cases,32.86%).Cases were predominantly among farmers(91.01%)and the Lisu ethnic group(52.68%).TB incidence showed weak seasonality with a bimodal distribution,with primary peak occurring from October to March and secondary peak from June to August.Tu'e Township(324.74 per 100,000),Shideng Township(307.42 per 100000),and Jinding Town(260.98 per 100,000)had the highest incidence rates,accounting for 1,284 cases or 45.28%of the county's total cases.In 2020,the incidence of pulmonary tuberculosis in Lanping County showed a spatial clustering distribution(global Morans's I value<0,P value<0.05),with Shideng Township consistently showing high-low aggregation characteristics.Conclusion Between 2018-2023,while the tuberculosis incidence rate in Lanping County has declined,it still falls short of Yunnan Province's tuberculosis prevention and control targets,and the prevention and control work continues to face significant challenges.Strengthening screening of high-risk populations and providing medical support to remote areas will be key measures for future prevention and treatment.
10.Pollution status and distribution characteristics of indoor air bacteria in subway stations and compartments in a city of Central South China
Shuyan CHENG ; Zhuojia GUI ; Liqin SU ; Guozhong TIAN ; Tanxi GE ; Jiao LUO ; Ranqi SHAO ; Feng LI ; Weihao XI ; Chunliang ZHOU ; Wei PENG ; Minlan PENG ; Min YANG ; Bike ZHANG ; Xianliang WANG ; Xiaoyuan YAO
Journal of Environmental and Occupational Medicine 2024;41(7):801-806
Background Bacteria are the most diverse and widely sourced microorganisms in the indoor air of subway stations, where pathogenic bacteria can spread through the air, leading to increased health risks. Objective To understand the status and distribution characteristics of indoor air bacterial pollution in subway stations and compartments in a city of Central South China, and to provide a scientific basis for formulating intervention measures to address indoor air bacteria pollution in subways. Methods Three subway stations and the compartments of trains parking there in a city in Central South China were selected according to passenger flow for synchronous air sampling and monitoring. Temperature, humidity, wind speed, carbon dioxide (CO2), fine particulate matter (PM2.5), and inhalable particulate matter (PM10) were measured by direct reading method. In accordance with the requirements of Examination methods for public places-Part 3: Airborne microorganisms (GB/T 18204.3-2013), air samples were collected at a flow rate of 28.3 L·min−1, and total bacterial count was estimated. Bacterial microbial species were identified with a mass spectrometer and pathogenic bacteria were distinguished from non-pathogenic bacteria according to the Catalogue of pathogenic microorganisms transmitted to human beings issued by National Health Commission. Kruskal-Wallis H test was used to compare the subway hygiene indicators in different regions and time periods, and Bonferroni test was used for pairwise comparison. Spearman correlation test was used to evaluate the correlation between CO2 concentration and total bacterial count. Results The pass rates were 100.0% for airborne total bacteria count, PM2.5, and PM10 in the subway stations and train compartments, 94.4% for temperature and wind speed, 98.6% for CO2, but 0% for humidity. The overall median (P25, P75) total bacteria count was 177 (138,262) CFU·m−3. Specifically, the total bacteria count was higher in station halls than in platforms, and higher during morning peak hours than during evening peak hours (P<0.05). A total of 874 strains and 82 species were identified by automatic microbial mass spectrometry. The results of identification were all over 9 points, and the predominant bacteria in the air were Micrococcus luteus (52.2%) and Staphylococcus hominis (9.8%). Three pathogens, Acinetobacter baumannii (0.3%), Corynebacterium striatum (0.1%), and Staphylococcus epidermidis bacilli (2.2%) were detected in 23 samples (2.6%), and the associated locations were mainly distributed in train compartments during evening rush hours. Conclusion The total bacteria count in indoor air varies by monitoring sites of subway stations and time periods, and there is a risk of opportunistic bacterial infection. Attention should be paid to cleaning and disinfection during peak passenger flow hours in all areas.

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