1.Engineered Bacteriophages for The Treatment of Multidrug-resistant Bacterial Infections
Yu-Ying CHEN ; Chun-Mei HUANG ; Jin-Zhi PAN ; De-Liang LIU ; Yang ZHOU ; Gui-Qin DAI ; Peng-Fei ZHAO ; Hong-Zhou LU ; Ming-Bin ZHENG
Progress in Biochemistry and Biophysics 2026;53(6):1581-1596
Multidrug-resistant (MDR) bacterial infections have emerged as a serious challenge of global public health crisis. The overuse and misuse of conventional antibiotics have dramatically accelerated the emergence, evolution and worldwide spread of drug-resistant bacterial strains, necessitating urgent exploration of novel antibacterial strategies. Bacteriophages serve as natural bacterial predators offering distinct advantages including high host specificity, autonomous self-replication capabilities and cost-effective large-scale production. However, wild-type phages present significant clinical limitations due to their narrow host ranges, susceptibility to rapid immune clearance and poor penetration of bacterial biofilms, which severely restrict their therapeutic applications. The convergence of synthetic biology, nanotechnology and advanced gene editing technologies has accelerated the development of engineered bacteriophage platforms, providing programmable, scalable and clinically translatable pathways to overcome these inherent biological constraints. Here, we systematically delineate four fundamental strategies for engineered bacteriophage development. Chemical modification utilizes reactive functional groups such as amino, carboxyl and thiol moieties on capsid proteins through esterification, amidation or click chemistry reactions to achieve precise drug conjugation and surface functionalization. In vivo editing encompasses ultraviolet or chemical mutagenesis for random mutation induction, homologous recombination for targeted genetic alterations, recombineering methodologies including electroporation-mediated bacteriophage recombination engineering, and CRISPR-Cas systems for precise genome editing to enable exact genetic reconstruction and host range reprogramming. In vitro synthesis leverages genome engineering platforms where intact phage genomes are transferred into yeast or host bacteria to facilitate highly efficient homologous recombination, enabling large DNA fragment assembly and cross-gene host range expansion without bacterial toxicity constraints. Directed evolution combines artificial selection through mutation library screening with rational design approaches involving chimeric receptor binding protein construction or site-specific mutagenesis, effectively balancing the discovery of unknown adaptive pathways with targeted host specificity modification. Moreover, we comprehensively discuss therapeutic applications across diverse clinical scenarios. Engineered bacteriophage effectively disrupt bacterial biofilms through sophisticated functionalized delivery platforms including nanozyme-conjugated phages, phage-liposome nanoconjugates and bio-responsive hydrogels, demonstrating significantly enhanced bactericidal efficiency compared to unmodified free phages. These bioengineered vectors attenuate bacterial virulence and resensitize pathogens to antibiotics by delivering CRISPR-Cas systems or base editors to disrupt critical virulence factors such as pili, capsule synthesis machineries and quorum sensing systems, or by inactivating antibiotic resistance determinants including beta-lactamase genes. As an intelligent nanomedicine delivery platform, engineered bacteriophage enable precise pathogen elimination an through photocatalytic reactive oxygen species generation, immunomodulatory interventions, or controlled release of antibacterial drugs. Furthermore, oral administration of engineered bacteriophage facilitates microbiota modulation, which selectively eliminate intestinal pathogens while preserve beneficial commensal microbiota, thereby restoring microbial community balance and preventing complications associated with dysbiosis. Finally, we critically analyze persistent challenges including host strain matching complexity, evolution of bacterial resistance mechanisms, pharmacokinetic optimization requirements, optimal administration route selection, large-scale production quality control standards and clinical dosing determination protocols. Through multidisciplinary integration of synthetic biology, infectious disease medicine and immunology, future translational medicine studies of bacteriophage should establish comprehensive technical platforms encompassing rapid phage screening, intelligent rational design, rigorous in vivo evaluation and standardized clinical validation processes, ultimately advancing engineered bacteriophage from laboratory innovations to clinically approved therapeutics for effectively combating MDR bacterial infections.
2.Introduction and enlightenment of the Recommendations and Expert Consensus for Plasm a and Platelet Transfusion Practice in Critically ill Children: from the Transfusion and Anemia Expertise Initiative-Control/Avoidance of Bleeding (TAXI-CAB)
Lu LU ; Jiaohui ZENG ; Hao TANG ; Lan GU ; Junhua ZHANG ; Zhi LIN ; Dan WANG ; Mingyi ZHAO ; Minghua YANG ; Rong HUANG ; Rong GUI
Chinese Journal of Blood Transfusion 2025;38(4):585-594
To guide transfusion practice in critically ill children who often need plasma and platelet transfusions, the Transfusion and Anemia Expertise Initiative-Control/Avoidance of Bleeding (TAXI-CAB) developed Recommendations and Expert Consensus for Plasma and Platelet Transfusion Practice in Critically Ill Children. This guideline addresses 53 recommendations related to plasma and platelet transfusion in critically ill children with 8 kinds of diseases, laboratory testing, selection/treatment of plasma and platelet components, and research priorities. This paper introduces the specific methods and results of the recommendation formation of the guideline.
3.Study on the prevalence of scoliosis and congenital heart disease in children and adolescents of Drung nationality in Yunnan Province
Haonan WANG ; Li ZHANG ; Genghao QIAN ; Zhi ZHAO ; Yingsong WANG ; Wenhui YANG ; Jiang LU ; Tao WANG ; Ni BI ; Xiaochen YANG ; Guanghong PU ; Weijie XIE ; Zhiyue SHI ; Tao LI
Chongqing Medicine 2025;54(7):1697-1702
Objective To investigate the prevalence of scoliosis and congenital heart disease(CHD)and their correlation among children and adolescents of Drung nationality in Yunnan Province.Methods A cross-sectional survey was conducted in November 2022 among all Drung school-aged children and adolescents aged 5-18 years in Gongshan Drung and Nu Autonomous County,Yunnan Province.Visual inspection,Adams for-ward flexion test,and trunk rotation angle(ATR)measurement were comprehensively used for school prelim-inary screening of scoliosis.Individuals who tested positive in the school preliminary screening underwent fur-ther X-ray examination for auxiliary diagnosis.Cardiac auscultation and echocardiography were used for school preliminary screening of CHD.The personal information of the screening subjects,the screening results,etc.were recorded.The prevalence of scoliosis and CHD among children and adolescents of the Drung nationality and the relationship between the two diseases were statistically analyzed,and the positive predictive value of school-based scoliosis screening and its influencing factors were also analyzed.Results A total of 1 036 chil-dren and adolescents of Drung nationality were enrolled,with a mean age of(10.72±3.75)years,icluding 542 males and 494 females.A total of 45 subjects tested positive for scoliosis in the school preliminary screening,with a preliminary positive rate of 4.34%.A total of 22 cases were finally diagnosed with scoliosis,with a prevalence rate of 2.12%.Among them,21 cases were idiopathic scoliosis(accounting for 95.45%),and 1 case was congenital scoliosis(accounting for 4.55%).The prevalence rate was higher in females(2.83%)than that in males(1.48%),higher in the 10 to 18-year-old group(2.30%)than that in the 5 to<10-year-old group(1.87%),and higher in the secondary school group(2.78%)than that in the primary school group(1.78%),hut there were no statistically significant differences(P>0.05).Most idiopathic scoliosis cases were mild(Cobb angle 10° to<20°,90.48%)and classified as Lenke type Ⅴ(57.14%).Two cases of CHD were confirmed,both of which were atrial septal defects,with a prevalence rate of 0.19%.The co-occurrence rate of idiopathic scoliosis and CHD was 4.76%(1/21).The positive predictive value of school-based scoliosis pre-liminary screening was only 48.89%.When the BMI was<18.5 kg/m2,the positive predictive value was sig-nificantly higher than that for BMI≥18.5 kg/m2(P<0.05).Conclusion The prevalence rate of scoliosis a-mong adolescents of the Drung ethnic group in Yunnan Province is 2.12%,predominantly idiopathic scoliosis,with Lenke type V being the most common classification.The prevalence rate of congenital heart disease is 0.19%.BMI is a significant influencing factor for the positive predictive value of school-based scoliosis prelimi-nary screening.
4.An Electronic Microbial Growth Analyzer-based Method for Rapidly Screening Viable Salmonella in Food
Ruo-Han LIANG ; Xiao-Dan PU ; Feng LU ; Xue-Ting ZHU ; Yuan-Yuan ZHANG ; Xiao-Yang WANG ; Qian-Qian YANG ; Hao LI ; Xu-Zhi ZHANG ; Chen-Zhong LI ; Shan LIU
Chinese Journal of Analytical Chemistry 2025;53(10):1694-1704
Foodborne illnesses caused by Salmonella pose significant threats to worldwide public health safety.In this study,a rapid method for screening viable Salmonella in oyster sauce and milk was developed by utilizing an electronic microbial growth analyzer(EMGA).Target food samples were diluted 10-fold with RVS broth and loaded into test tubes.Test tubes were positioned in the EMGA to determine the bacterial growth curves and the time required to reach the maximum growth rate(Tmgr).Using Salmonella typhimurium(S.typhimurium)asan model species,there was linear relationship between the logarithmic value of viable bacterial concentration(lgC)and Tmgr over the range of 5×101-5×106 CFU/mL,with a detection limit of 10 CFU/mL.For oyster sauce,the regression equation was Tmgr(min)=-80.775lg[C/(CFU/mL)]+754.96(R2=0.9907),and the recovery rates of S.typhimurium ranged from 95.2%to 119.8%,with relative standard deviations(RSD)ranging from 3.5%to 16.3%.For milk,the regression equation was Tmgr(min)=-71.922 lg[C/(CFU/mL)]+618.65(R2=0.9985),with recovery rates ranging from 98.4%to 110.6%and RSD ranging from 6.4%to 12.8%.The EMGA method required only one portable instrument,and involving only three manual steps,i.e.,dilution,transfer,and insertion.When S.typhimurium contamination reached 106 CFU/mL,the total time consumption,from the unwrapping of samples to the readout of bacterial concentration,was no more than 7 h.When applied to detection of actual oyster sauce and milk samples,the new method demonstrated strong consistency with plate counting results in positive detection rates.This method was superior to the plate counting method,which was generally considered as a gold standard,in terms of accuracy,precision,simplicity and efficiency,representing a promising alternative for the on-site screening and quantification of viable Salmonella in oyster sauce and milk products.
5.Establishment of real-time fluorescence quantitative PCR method for detecting the N subgenome of SARS-CoV-2
Taoli HAN ; Zhi ZHANG ; Jiaxin ZHAO ; Pan LU ; Yang JIAO ; Jianhong ZHAO ; Yan GAO ; Shiyao ZHANG ; Kuankuan LIU ; Yujie LIU ; Ru FAN ; Wenjing LI ; Lingli SUN
Chinese Journal of Experimental and Clinical Virology 2025;39(1):96-101
Objective:To establish a fluorescent quantitative RT-PCR assay based on N_sgRNA of SARS-CoV-2 and preliminarily apply it on real samples.Methods:Recombinant plasmid, specific primers and probes of N_sgRNA were designed and synthesized based on Wuhan-Hu-1/2019_MN908947 and synthesis mechanism of subgenomic RNA (sgRNA). Using recombinant plasmid as amplification templates, the optimal reaction conditions and reaction system were screened according to the Ct value, fluorescence intensity, and shape of amplification curve and was evaluated for sensitivity, reproducibility, and specificity. Meanwhile, the possibility of practical application of the method was explored by testing 172 clinical samples and 256 municipal wastewater samples. Results:A qRT-PCR assay for N_sgRNA in SARS-CoV-2 was initially established. The detection limit of the assay was 20 copies/mL, and the variation coefficients of in-batch (0.002%~0.767%) and batch to batch repetition (0.016%~0.752%) were less than 1%. Only N_sgRNA recombinant plasmid was detected in the specificity assay. So the method is more highly sensitive, specific and reproducible. The RatiosgRNA/ gRNA of clinical samples HK.3, EG.5.1, JN.1 and their sub-lineages and their corresponding urban sewage samples in epidemic period were significantly different ( P<0.05). There is a strong correlation between the median of RatiosgRNA/ gRNA in clinical samples and sewage samples in the same period (correlation coefficient r=1.000, P=0.010). Conclusions:In this study, a qRT-PCR method for detecting N_sgRNA of SARS-CoV-2 was established and the method has the characteristics of higher sensitivity, stronger specificity and better repeatability, and it can be used to detect SARS-CoV-2 infectivity.
6.Zedoarondiol Inhibits Neovascularization in Atherosclerotic Plaques of ApoE-/- Mice by Reducing Platelet Exosomes-Derived MiR-let-7a.
Bei-Li XIE ; Bo-Ce SONG ; Ming-Wang LIU ; Wei WEN ; Yu-Xin YAN ; Meng-Jie GAO ; Lu-Lian JIANG ; Zhi-Die JIN ; Lin YANG ; Jian-Gang LIU ; Da-Zhuo SHI ; Fu-Hai ZHAO
Chinese journal of integrative medicine 2025;31(3):228-239
OBJECTIVE:
To investigate the effect of zedoarondiol on neovascularization of atherosclerotic (AS) plaque by exosomes experiment.
METHODS:
ApoE-/- mice were fed with high-fat diet to establish AS model and treated with high- and low-dose (10, 5 mg/kg daily) of zedoarondiol, respectively. After 14 weeks, the expressions of anti-angiogenic protein thrombospondin 1 (THBS-1) and its receptor CD36 in plaques, as well as platelet activation rate and exosome-derived miR-let-7a were detected. Then, zedoarondiol was used to intervene in platelets in vitro, and miR-let-7a was detected in platelet-derived exosomes (Pexo). Finally, human umbilical vein endothelial cells (HUVECs) were transfected with miR-let-7a mimics and treated with Pexo to observe the effect of miR-let-7a in Pexo on tube formation.
RESULTS:
Animal experiments showed that after treating with zedoarondiol, the neovascularization density in plaques of AS mice was significantly reduced, THBS-1 and CD36 increased, the platelet activation rate was markedly reduced, and the miR-let-7a level in Pexo was reduced (P<0.01). In vitro experiments, the platelet activation rate and miR-let-7a levels in Pexo were significantly reduced after zedoarondiol's intervention. Cell experiments showed that after Pexo's intervention, the tube length increased, and the transfection of miR-let-7a minics further increased the tube length of cells, while reducing the expressions of THBS-1 and CD36.
CONCLUSION
Zedoarondiol has the effect of inhibiting neovascularization within plaque in AS mice, and its mechanism may be potentially related to inhibiting platelet activation and reducing the Pexo-derived miRNA-let-7a level.
Animals
;
MicroRNAs/genetics*
;
Exosomes/drug effects*
;
Plaque, Atherosclerotic/genetics*
;
Neovascularization, Pathologic/genetics*
;
Human Umbilical Vein Endothelial Cells/metabolism*
;
Humans
;
Blood Platelets/drug effects*
;
Apolipoproteins E/deficiency*
;
Thrombospondin 1/metabolism*
;
CD36 Antigens/metabolism*
;
Platelet Activation/drug effects*
;
Male
;
Mice
;
Mice, Inbred C57BL
7.Efficacy and safety of a facilitated percutaneous coronary intervention with half-dose recombinant staphylokinase in ST-segment elevation myocardial infarction
Tian-yu WU ; Wen-hao ZHANG ; Peng-sheng CHEN ; Chen LI ; Tian WU ; Zhan LÜ ; Tong WANG ; Kun LIU ; Zhi-wen TAO ; Xiao-xuan GONG ; Liang YUAN ; Yong LI ; Bo CHEN ; Xin CHEN ; Zeng-guang CHEN ; Nai-quan YANG ; Yuan-yuan SANG ; Xiao-yan WANG ; Bai-hong LI ; Li ZHU ; Guo-yu WANG ; Xin ZHAO ; Chuan LU ; Jun JIANG ; Rui-na HAO ; Chun-jian LI
Chinese Journal of Interventional Cardiology 2025;33(8):431-438
Objective To investigate the clinical efficacy and safety of facilitated percutaneous coronary intervention(PCI)with half-dose recombinant staphylokinase(r-SAK)in patients with ST-segment elevation myocardial infarction(STEMI)who are expected to undergo PCI within 120 minutes.Methods From October 2021 to August 2022,a total of 200 STEMI patients in eight centers were included and randomly assigned in a 1﹕1 ratio to either r-SAK group or control group.Patients received loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive an intravenous bolus of either 5 mg r-SAK or normal saline prior to PCI.The outcomes were set as ST-segment resolution(STR)at 60-90 minutes after PCI,the proportion and transition of pathological Q waves on the 5th day after PCI,and the proportion of high-sensitivity cardiac troponin T(hs-cTnT)peaking within 12 hours of onset.The safety outcome was major bleeding events defined as Bleeding Academic Research Consortium(BARC)≥type 3 bleeding during hospitalization.Results Compared with the control group,the r-SAK group had a higher proportion of STR≥70%within 60-90 minutes after PCI(58.3%vs.40.3%,P=0.009);a lower proportion of pathological Q waves(59.1%vs.74.1%,P=0.040);a lower rate of Q wave progression(14.8%vs.43.2%,P<0.001);a higher rate of Q wave disappearance(12.5%vs.3.7%,P=0.027);and a higher proportion of hs-cTnT peaking within 12 hours of symptom onset[31/40(77.5%)vs.17/33(51.5%),P=0.027].Regarding the safety outcome,no significant difference in BARC≥type 3 bleeding was found between the two groups during hospitalization(P>0.05).Conclusions For STEMI patients who were expected to undergo primary PCI within 120 minutes of symptom onset,the facilitated PCI with half-dose r-SAK significantly increased the proportion of STR≥70%at 60-90 minutes after PCI,reduced the formation of pathological Q waves,and shortened the time to peak hs-cTnT,without increasing the risk of bleeding,which should be an alternative reperfusion strategy worthy of further study.
8.Expert consensus on pulpotomy in the management of mature permanent teeth with pulpitis.
Lu ZHANG ; Chen LIN ; Zhuo CHEN ; Lin YUE ; Qing YU ; Benxiang HOU ; Junqi LING ; Jingping LIANG ; Xi WEI ; Wenxia CHEN ; Lihong QIU ; Jiyao LI ; Yumei NIU ; Zhengmei LIN ; Lei CHENG ; Wenxi HE ; Xiaoyan WANG ; Dingming HUANG ; Zhengwei HUANG ; Weidong NIU ; Qi ZHANG ; Chen ZHANG ; Deqin YANG ; Jinhua YU ; Jin ZHAO ; Yihuai PAN ; Jingzhi MA ; Shuli DENG ; Xiaoli XIE ; Xiuping MENG ; Jian YANG ; Xuedong ZHOU ; Zhi CHEN
International Journal of Oral Science 2025;17(1):4-4
Pulpotomy, which belongs to vital pulp therapy, has become a strategy for managing pulpitis in recent decades. This minimally invasive treatment reflects the recognition of preserving healthy dental pulp and optimizing long-term patient-centered outcomes. Pulpotomy is categorized into partial pulpotomy (PP), the removal of a partial segment of the coronal pulp tissue, and full pulpotomy (FP), the removal of whole coronal pulp, which is followed by applying the biomaterials onto the remaining pulp tissue and ultimately restoring the tooth. Procedural decisions for the amount of pulp tissue removal or retention depend on the diagnostic of pulp vitality, the overall treatment plan, the patient's general health status, and pulp inflammation reassessment during operation. This statement represents the consensus of an expert committee convened by the Society of Cariology and Endodontics, Chinese Stomatological Association. It addresses the current evidence to support the application of pulpotomy as a potential alternative to root canal treatment (RCT) on mature permanent teeth with pulpitis from a biological basis, the development of capping biomaterial, and the diagnostic considerations to evidence-based medicine. This expert statement intends to provide a clinical protocol of pulpotomy, which facilitates practitioners in choosing the optimal procedure and increasing their confidence in this rapidly evolving field.
Humans
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Calcium Compounds/therapeutic use*
;
Consensus
;
Dental Pulp
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Dentition, Permanent
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Oxides/therapeutic use*
;
Pulpitis/therapy*
;
Pulpotomy/standards*
9.Association between Per and Polyfluoroalkyl Substance and Abdominal Fat Distribution: A Trait Spectrum Exposure Pattern and Structure-Based Investigation.
Zhi LI ; Shi Lin SHAN ; Chen Yang SONG ; Cheng Zhe TAO ; Hong QIAN ; Qin YUAN ; Yan ZHANG ; Qiao Qiao XU ; Yu Feng QIN ; Yun FAN ; Chun Cheng LU
Biomedical and Environmental Sciences 2025;38(1):3-14
OBJECTIVE:
To investigate the associations between eight serum per- and polyfluoroalkyl substances (PFASs) and regional fat depots, we analyzed the data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018 cycles.
METHODS:
Multiple linear regression models were developed to explore the associations between serum PFAS concentrations and six fat compositions along with a fat distribution score created by summing the concentrations of the six fat compositions. The associations between structurally grouped PFASs and fat distribution were assessed, and a prediction model was developed to estimate the ability of PFAS exposure to predict obesity risk.
RESULTS:
Among females aged 39-59 years, trunk fat mass was positively associated with perfluorooctane sulfonate (PFOS). Higher concentrations of PFOS, perfluorohexane sulfonate (PFHxS), perfluorodecanoate (PFDeA), perfluorononanoate (PFNA), and n-perfluorooctanoate (n-PFOA) were linked to greater visceral adipose tissue in this group. In men, exposure to total perfluoroalkane sulfonates (PFSAs) and long-chain PFSAs was associated with reductions in abdominal fat, while higher abdominal fat in women aged 39-59 years was associated with short-chain PFSAs. The prediction model demonstrated high accuracy, with an area under the curve (AUC) of 0.9925 for predicting obesity risk.
CONCLUSION
PFAS exposure is associated with regional fat distribution, with varying effects based on age, sex, and PFAS structure. The findings highlight the potential role of PFAS exposure in influencing fat depots and obesity risk, with significant implications for public health. The prediction model provides a highly accurate tool for assessing obesity risk related to PFAS exposure.
Humans
;
Fluorocarbons/blood*
;
Female
;
Adult
;
Middle Aged
;
Male
;
Environmental Pollutants/blood*
;
Abdominal Fat
;
Nutrition Surveys
;
Alkanesulfonic Acids/blood*
;
Obesity
;
Environmental Exposure
10.Independent and Interactive Effects of Air Pollutants, Meteorological Factors, and Green Space on Tuberculosis Incidence in Shanghai.
Qi YE ; Jing CHEN ; Ya Ting JI ; Xiao Yu LU ; Jia le DENG ; Nan LI ; Wei WEI ; Ren Jie HOU ; Zhi Yuan LI ; Jian Bang XIANG ; Xu GAO ; Xin SHEN ; Chong Guang YANG
Biomedical and Environmental Sciences 2025;38(7):792-809
OBJECTIVE:
To assess the independent and combined effects of air pollutants, meteorological factors, and greenspace exposure on new tuberculosis (TB) cases.
METHODS:
TB case data from Shanghai (2013-2018) were obtained from the Shanghai Center for Disease Control and Prevention. Environmental data on air pollutants, meteorological variables, and greenspace exposure were obtained from the National Tibetan Plateau Data Center. We employed a distributed-lag nonlinear model to assess the effects of these environmental factors on TB cases.
RESULTS:
Increased TB risk was linked to PM 2.5, PM 10, and rainfall, whereas NO 2, SO 2, and air pressure were associated with a reduced risk. Specifically, the strongest cumulative effects occurred at various lags: PM 2.5 ( RR = 1.166, 95% CI: 1.026-1.325) at 0-19 weeks; PM 10 ( RR = 1.167, 95% CI: 1.028-1.324) at 0-18 weeks; NO 2 ( RR = 0.968, 95% CI: 0.938-0.999) at 0-1 weeks; SO 2 ( RR = 0.945, 95% CI: 0.894-0.999) at 0-2 weeks; air pressure ( RR = 0.604, 95% CI: 0.447-0.816) at 0-8 weeks; and rainfall ( RR = 1.404, 95% CI: 1.076-1.833) at 0-22 weeks. Green space exposure did not significantly impact TB cases. Additionally, low temperatures amplified the effect of PM 2.5 on TB.
CONCLUSION
Exposure to PM 2.5, PM 10, and rainfall increased the risk of TB, highlighting the need to address air pollutants for the prevention of TB in Shanghai.
China/epidemiology*
;
Humans
;
Air Pollutants/analysis*
;
Tuberculosis/epidemiology*
;
Incidence
;
Meteorological Concepts
;
Particulate Matter/adverse effects*
;
Environmental Exposure
;
Male
;
Female
;
Adult
;
Air Pollution
;
Middle Aged

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