ObjectiveTo explore the effect and mechanism of Taishan Panshi powder （TSPSP） on inhibiting oxidative stress injury in human chorionic trophoblast cells （HTR-8/SVneo）， and to uelucidate the underlying mechanism of TSPSP in the treatment of spontaneous abortion （SA）. MethodsGene differential analysis of SA was performed using the Gene Expression Omnibus （GEO） database and correlated with oxidative stress. Network pharmacology was employed to screen the active components of TSPSP， and a "Chinese medicine-component-target-disease" network was constructed to predict the mechanism of action of TSPSP. For in vitro validation experiments， HTR-8/SVneo cells were divided into blank group， model group， TSPSP-containing serum 2.5%， 5%， 10% groups， and nuclear factor E₂-related factor 2 （Nrf2） inhibitor group （ML385， 30 μmol·L^-1）. Except for the blank group， other groups were stimulated with 150 μmol·L^-1 H₂O₂ for 3 h to establish a cell oxidative stress injury model. After successful modeling， the blank group and model group were given 10% blank serum， each TSPSP-containing serum group was treated with the corresponding concentration of drug-containing serum， and the Nrf2 inhibitor group was additionally given 30 μmol·L^-1 ML385 on the basis of 10% TSPSP-containing serum. All groups of cells were continuously cultured under the above conditions for 24 h， and then samples were collected for subsequent detection. Cell viability in each group was detected by CCK-8 assay. Cell migration rate was detected by scratch test. The contents of malondialdehyde （MDA）， Fe²⁺， and Glutathione （GSH） were detected by enzyme-linked immunosorbent assay （ELISA）. Intracellular reactive oxygen species （ROS） level was detected by a fluorescent probe （DCF-DA）. The protein and mRNA expression levels of Kelch-like ECH-associated protein 1 （KEAP1）， Nrf2， and forkhead box protein O3 （FoxO3） in cells were detected by immunofluorescence （IF） and real-time quantitative polymerase chain reaction （Real-time PCR）. The protein expression levels of KEAP1， Nrf2， FoxO3， Glutathione peroxidase 4 （GPX4）， and superoxide dismutase （SOD） in cells were detected by Western blot. ResultsThe GSE76862 and GSE22490 datasets were obtained from the GEO database. Differential gene analyses showed that the KEAP1， Nrf2， and FoxO3 genes were all associated with the disease. After matching with the oxidative stress pathway， nine significantly differential pathways were identified （P<0.05）， among which three contained the target genes Nrf2 and FoxO3. A total of 246 active ingredient targets of TSPSP and 2 804 SA-related targets were obtained through network pharmacology， and 154 potential action targets were obtained after taking the intersection. Topological analysis showed that targets such as KEAP1 and Nrf2 exhibited high degree values. GO and KEGG enrichment analyses indicated that the intersection targets were mainly involved in oxidative stress response， FOXO and MAPK signaling pathways， etc. In in vitro experiments， compared with the blank group， the cell viability in the model group was significantly decreased （P<0.01）. Compared with the model group， the cell viability in each TSPSP-containing serum group was significantly increased （P<0.01）. Compared with the 10% TSPSP-containing serum group， the cell viability in the ML385 group decreased to approximately 70% （P<0.01）. Compared with the blank group， the model group showed significantly increased contents of MDA， Fe²⁺， and ROS， decreased GSH expression （P<0.01）， significantly reduced cell migration rate （P<0.01）， and increased protein and mRNA expression levels of KEAP1 and FoxO3 （P<0.01）， while decreased protein and mRNA expression levels of Nrf2， GPX4， and SOD （P<0.01）. Compared with the model group， each TSPSP-containing serum group showed significantly decreased contents of MDA， Fe²⁺， and ROS， increased GSH expression （P<0.01）， significantly increased migration rate （P<0.01）， significantly decreased protein and mRNA expression levels of KEAP1 and FoxO3 （P<0.05， P<0.01）， and significantly increased protein and mRNA expression levels of Nrf2， GPX4， and SOD （P<0.05， P<0.01）. Compared with the 10% TSPSP-containing serum group， the ML385 group showed reversed trends in all indicators （P<0.05， P<0.01）. ConclusionTSPSP can inhibit H₂O₂-induced oxidative stress injury of trophoblast cells， and its mechanism of action may be related to the drug activating the KEAP1/Nrf2/FoxO3 signaling pathway.

ObjectiveTo explore the effect and mechanism of Taishan Panshi powder （TSPSP） on inhibiting oxidative stress injury in human chorionic trophoblast cells （HTR-8/SVneo）， and to uelucidate the underlying mechanism of TSPSP in the treatment of spontaneous abortion （SA）. MethodsGene differential analysis of SA was performed using the Gene Expression Omnibus （GEO） database and correlated with oxidative stress. Network pharmacology was employed to screen the active components of TSPSP， and a "Chinese medicine-component-target-disease" network was constructed to predict the mechanism of action of TSPSP. For in vitro validation experiments， HTR-8/SVneo cells were divided into blank group， model group， TSPSP-containing serum 2.5%， 5%， 10% groups， and nuclear factor E₂-related factor 2 （Nrf2） inhibitor group （ML385， 30 μmol·L^-1）. Except for the blank group， other groups were stimulated with 150 μmol·L^-1 H₂O₂ for 3 h to establish a cell oxidative stress injury model. After successful modeling， the blank group and model group were given 10% blank serum， each TSPSP-containing serum group was treated with the corresponding concentration of drug-containing serum， and the Nrf2 inhibitor group was additionally given 30 μmol·L^-1 ML385 on the basis of 10% TSPSP-containing serum. All groups of cells were continuously cultured under the above conditions for 24 h， and then samples were collected for subsequent detection. Cell viability in each group was detected by CCK-8 assay. Cell migration rate was detected by scratch test. The contents of malondialdehyde （MDA）， Fe²⁺， and Glutathione （GSH） were detected by enzyme-linked immunosorbent assay （ELISA）. Intracellular reactive oxygen species （ROS） level was detected by a fluorescent probe （DCF-DA）. The protein and mRNA expression levels of Kelch-like ECH-associated protein 1 （KEAP1）， Nrf2， and forkhead box protein O3 （FoxO3） in cells were detected by immunofluorescence （IF） and real-time quantitative polymerase chain reaction （Real-time PCR）. The protein expression levels of KEAP1， Nrf2， FoxO3， Glutathione peroxidase 4 （GPX4）， and superoxide dismutase （SOD） in cells were detected by Western blot. ResultsThe GSE76862 and GSE22490 datasets were obtained from the GEO database. Differential gene analyses showed that the KEAP1， Nrf2， and FoxO3 genes were all associated with the disease. After matching with the oxidative stress pathway， nine significantly differential pathways were identified （P<0.05）， among which three contained the target genes Nrf2 and FoxO3. A total of 246 active ingredient targets of TSPSP and 2 804 SA-related targets were obtained through network pharmacology， and 154 potential action targets were obtained after taking the intersection. Topological analysis showed that targets such as KEAP1 and Nrf2 exhibited high degree values. GO and KEGG enrichment analyses indicated that the intersection targets were mainly involved in oxidative stress response， FOXO and MAPK signaling pathways， etc. In in vitro experiments， compared with the blank group， the cell viability in the model group was significantly decreased （P<0.01）. Compared with the model group， the cell viability in each TSPSP-containing serum group was significantly increased （P<0.01）. Compared with the 10% TSPSP-containing serum group， the cell viability in the ML385 group decreased to approximately 70% （P<0.01）. Compared with the blank group， the model group showed significantly increased contents of MDA， Fe²⁺， and ROS， decreased GSH expression （P<0.01）， significantly reduced cell migration rate （P<0.01）， and increased protein and mRNA expression levels of KEAP1 and FoxO3 （P<0.01）， while decreased protein and mRNA expression levels of Nrf2， GPX4， and SOD （P<0.01）. Compared with the model group， each TSPSP-containing serum group showed significantly decreased contents of MDA， Fe²⁺， and ROS， increased GSH expression （P<0.01）， significantly increased migration rate （P<0.01）， significantly decreased protein and mRNA expression levels of KEAP1 and FoxO3 （P<0.05， P<0.01）， and significantly increased protein and mRNA expression levels of Nrf2， GPX4， and SOD （P<0.05， P<0.01）. Compared with the 10% TSPSP-containing serum group， the ML385 group showed reversed trends in all indicators （P<0.05， P<0.01）. ConclusionTSPSP can inhibit H₂O₂-induced oxidative stress injury of trophoblast cells， and its mechanism of action may be related to the drug activating the KEAP1/Nrf2/FoxO3 signaling pathway.

BACKGROUND:Small diameter artificial vessels are urgently needed to treat coronary artery and peripheral artery diseases in clinical practice.At present,vascular tissue engineering has become the main method for preparing small diameter artificial vessels.Selecting suitable biomaterials and cell sources is the key factor for successful construction of small diameter tissue engineered vessels. OBJECTIVE:To observe the effect of four kinds of electrospinning membrane materials on proliferation,adhesion and differentiation of bone marrow mesenchymal stem cells into vascular smooth muscle cells. METHODS:Bone marrow mesenchymal stem cells were isolated and extracted from SD rats.The bone marrow mesenchymal stem cells were inoculated separately on polycaprolactone(PCL),polycaprolactone-hyaluronic acid(PCL-HA),polycaprolactone-silk-filament proteins(PCL-SF),and polycaprolactone-gelatin(PCL-GEL)electrospinning membrane materials.After 1,3,and 7 days of culture,the cell arrangement on the material was observed under scanning electron microscope.The proliferation and adhesion of the material were observed by phalloidin staining.The mRNA expressions of CD90,Meflin,and transforming growth factor β were detected by qRT-PCR.After 7 days of induced differentiation into vascular smooth muscle cells,the mRNA expression ofɑ-smooth muscle actin on the material was detected by qRT-PCR. RESULTS AND CONCLUSION:(1)Bone marrow mesenchymal stem cells were arranged along the fibers of the four kinds of electrospinning membranes under scanning electron microscopy.(2)Phalloidin staining showed the regular distribution of bone marrow mesenchymal stem cells on the four kinds of electrospinning membranes and parallel distribution along the fiber direction.Moreover,PCL-HA,PCL-SF,and PCL-GEL electrospinning membranes were more conducive to the proliferation and adhesion of bone marrow mesenchymal stem cells than PCL electrospinning membranes.Compared with PCL-HA and PCL-GEL electrospinning membranes,PCL-SF electrospinning membranes were more conducive to the proliferation and adhesion of bone marrow mesenchymal stem cells.(3)qRT-PCR showed that the four kinds of electrospun membrane materials could maintain the mRNA expression of CD90 and Meflin in bone marrow mesenchymal stem cells,but there was no significant difference between groups(P>0.05).The mRNA expression of transforming growth factor β in PCL-HA,PCL-SF,and PCL-GEL groups was higher than that in PCL group on days 1 and 7(P<0.05),and the mRNA expression of transforming growth factor β in PCL-SF group was higher than that in the other three groups on days 3 and 7(P<0.05).The mRNA expression of transforming growth factor β in PCL-HA group was higher than that in PCL-GEL group on day 7(P<0.05).(4)qRT-PCR showed that the mRNA expression of ɑ-smooth muscle actin in PCL-SF group was higher than that in the other three groups(P<0.05),and that in PCL-HA group was higher than that in PCL group(P<0.05).(5)The results indicate that compared with PCL,PCL-HA and PCL-GEL electrospinning membranes,PCL-SF electrospinning membranes combined with bone marrow mesenchymal stem cells are more suitable for the preparation of small diameter tissue engineered vessels.

ObjectiveTo investigate the effects of Xixintang （XXT）-medicated serum on the amyloid β-protein （Aβ）_25-35-induced polarization of BV-2 microglial cells by a cell experiment and uncover the potential mechanisms of this formula in the prevention and treatment of Alzheimer's disease （AD）， thus providing scientific evidence for the clinical application of XXT. MethodsBV-2 microglial cells were subcultured. The optimal concentrations of XXT-medicated serum and Aβ_25-35 were determined via the cell-counting kit-8 （CCK-8） assay. The cell experiment was carried out with the following groups： blank control， model （Aβ_25-35 at 40 μmol·L^-1）， XXT-medicated serum （Aβ_25-35 at 40 μmol·L^-1 + 10% XXT-medicated serum）， and blank serum （Aβ_25-35 at 40 μmol·L^-1 + 10% blank serum）. After 24 hours of cell incubation， immunofluorescence was used to detect the expression of ionized calcium-binding adaptor molecule 1 （IBA1）， CD16/32， and CD206. Real-time PCR was performed to measure the mRNA levels of CD206， CD163， inducible nitric oxide synthase （iNOS）， and arginase 1 （Arg-1）. Enzyme-linked immunosorbent assay （ELISA） was employed to quantify the levels of nerve growth factor （NGF）， iNOS， and Arg-1. The nitric oxide （NO） concentration was determined via the nitrate reductase method. ResultsCompared with the blank control group， the model group showed increased expression of IBA1 and CD16/32 （P<0.01）， decreased expression of CD206 （P<0.05）， upregulation in the mRNA level （P<0.01） and content （P<0.05） of iNOS， downregulation in the mRNA levels of CD206， CD163， and Arg-1 （P<0.05， P<0.01）， lowered levels of Arg-1 and NGF （P<0.05）， and an elevation in the NO level （P<0.05）. Compared with the model group， the XXT-medicated serum group exhibited reduced expression of IBA1 and CD16/32 （P<0.05， P<0.01） and increased expression of CD206 （P<0.01）. Both the content and mRNA level of iNOS were downregulated （P<0.05， P<0.01）， while the mRNA levels of CD206， CD163， and Arg-1 were upregulated （P<0.01） in the XXT-medicated serum group. In addition， the XXT-medicated serum group showed elevated levels of Arg-1 and NGF （P<0.05） and a lowered level of NO （P<0.05）. The blank serum group showed no statistically significant differences in the measured parameters compared with the model group. ConclusionThe XXT-medicated serum can inhibit the polarization toward the M1 phenotype and promote the polarization toward the M2 phenotype， exerting anti-inflammatory and neurotrophic effects.

ObjectiveTo investigate the effects of Yiqi Wenyang Huoxue Lishui components on the cardiac function and mitochondrial energy metabolism in the rat model of chronic heart failure （CHF） and explore the underlying mechanism. MethodsThe rat model of CHF was prepared by transverse aortic constriction （TAC）. Eight of the 50 SD rats were randomly selected as the sham group， and the remaining 42 underwent TAC surgery. The 24 SD rats successfully modeled were randomized into model， trimetazidine （6.3 mg·kg^-1）， and Yiqi Wenyang Huoxue Lishui components （60 mg·kg^-1 total saponins of Astragali Radix， 10 mg·kg^-1 total phenolic acids of Salviae Miltiorrhizae Radix et Rhizoma， 190 mg·kg^-1 aqueous extract of Lepidii Semen， and 100 mg·kg^-1 cinnamaldehyde） groups. The rats were administrated with corresponding agents by gavage， and those in the sham and model groups were administrated with the same amount of normal saline at a dose of 10 mL·kg^-1 for 8 weeks. Echocardiography was used to examine the cardiac function in rats. Enzyme-linked immunosorbent assay was employed to determine the serum levels of N-terminal pro-B-type natriuretic peptide （NT-ProBNP）， hypersensitive troponin（cTnI）， creatine kinase （CK）， lactate dehydrogenase （LD）， free fatty acids （FFA）， superoxide dismutase （SOD）， and malondialdehyde （MDA）. The colorimetric assay was employed to measure the levels of adenosine triphosphate （ATP）， adenosine diphosphate （ADP）， and adenosine monophosphate （AMP） in the myocardial tissue. The pathological changes in the myocardial tissue were observed by hematoxylin-eosin staining and Masson staining. The Na⁺-K⁺-ATPase and Ca²⁺-Mg²⁺-ATPase activities in the myocardial tissue were determined by the colorimetric assay. The ultrastructural changes of myocardial mitochondria were observed by transmission electron microscopy. Western blot was employed to determine the protein levels of ATP synthase subunit delta （ATP5D）， glucose transporter 4 （GLUT4）， and carnitine palmitoyltransferase-1 （CPT-1）. The mitochondrial complex assay kits were used to determine the activities of mitochondrial complexes Ⅰ， Ⅱ， Ⅲ， and Ⅳ. ResultsCompared with the sham group， the model group showed a loosening arrangement of cardiac fibers， fracture and necrosis of partial cardiac fibers， inflammatory cells in necrotic areas， massive blue fibrotic tissue in the myocardial interstitium， increased collagen fiber area and myocardial fibrosis， destroyed mitochondria， myofibril disarrangement， sparse myofilaments， and fractured and reduced cristae. In addition， the rats in the model group showed declined ejection fraction （EF） and fractional shortening （FS）， risen left ventricular end-diastolic diameter （LVIDd）， left ventricular end-systolic diameter （LVIDs）， left ventricular end-diastolic posterior wall thickness （LVPWd）， left ventricular end-systolic posterior wall thickness （LVPWs）， left ventricular end-diastolic volume （LVVOLd）， and left ventricular end-systolic volume （LVVOLs）， elevated levels of NT-ProBNP， cTnI， CK， MDA， FFA， and LD， lowered level of SOD， down-regulated protein levels of GLUT4 and CPT-1， decreased activities of Na⁺-K⁺-ATPase， Ca²⁺-Mg²⁺-ATPase， and respiratory complexes Ⅰ-Ⅳ， and declined levels of ATP5D， ATP， ADP， and AMP （P<0.05， P<0.01）. Compared with the model group， the Yiqi Wenyang Huoxue Lishui components and trimetazidine groups showed alleviated pathological damage of the mitochondria and mycardial tissue， risen EF and FS， declined LVIDd， LVIDs， LVPWd， LVPWs， LVVOLd， and LVVOLs， lowered levels of NT-ProBNP， cTnI， CK， MDA， FFA， and LD， elevated level of SOD， up-regulated protein levels of GLUT4 and CPT-1， increased activities of Na⁺-K⁺-ATPase， Ca²⁺-Mg²⁺-ATPase， and respiratory complexes Ⅰ-Ⅳ， and elevated levels of ATP5D， ATP， ADP， and AMP （P<0.05， P<0.01）. ConclusionYiqi Wenyang Huoxue Lishui components can improve the cardiac function， reduce myocardial injury， regulate glucose and lipid metabolism， optimize the utilization of substrates， and alleviate the damage of mitochondrial structure and function， thus improving the energy metabolism of the myocardium in the rat model of CHF.

ObjectiveTo explore the potential mechanism of Xixin Decoction （洗心汤， XD） in treating Alzheimer's disease （AD）. MethodsXD-containing serum was prepared， and the BV-2 microglial cell viability was assessed using the CCK8 assay to determine the optimal intervention concentrations of XD-containing serum and amyloid-beta _25-35 （Aβ_25-35） for subsequent experiments. BV-2 cells were divided into four groups， control group， model group （Aβ_25-35）， XD-containing serum group （Aβ_25-35+ XD-containing serum）， and blank serum group （Aβ_25-35 + blank serum）. After 24 hours of culture， the levels of interleukin-1β（IL-1β）， cyclooxygenase-2 （COX-2）， and arginase-2 （Arg-2） in the supernatent were detected by ELISA. Immunofluorescence staining was performed to detect the protein levels of ionized calcium-binding adaptor molecule 1 （IBA1）， CD86， and CD206. RT-PCR was used to analyze the mRNA expression of IL-1β， interleukin-6 （IL-6）， and interleukin-10 （IL-10）. ResultsThe concentrations of 10% XD-containing serum and 40 μmol·L^-¹ Aβ_25-35 were selected for subsequent experiments. Compared to the control group， the model group showed significantly increased levels of IL-1β and COX-2 in the supernatant， as well as elevated protein expression of IBA1 and CD86 and increased mRNA expression of IL-1β and IL-6， while exhibiting significantly reduced levels of Arg-2 in the supernatant， CD206 protein expression， and IL-10 mRNA expression （P＜0.05 or P＜0.01）. Compared to the model group， the XD-containing serum group showed significant improvement in all these indicators （P＜0.01）， whereas no statistically significant differences were observed in the blank serum group （P＞0.05）. ConclusionXD may regulate microglial activation， inhibit pro-inflammatory factors， and enhance anti-inflammatory factor release， thereby improving neuroimmune inflammation and inhibiting the progression of Alzheimer's disease.

Objective:To investigate the risk factors of wet ear status and its impact on the efficacy of endoscopic type Ⅰ tympanoplasty. Methods:A retrospective analysis was conducted at the Department of Otolaryngology Head and Neck Surgery, the First Affiliated Hospital of Chinese People's Liberation Army（PLA）Air Force Medical University, on 160 ears that underwent endoscopic type Ⅰ tympanoplasty; these were assigned to a dry-ear group （n= 118） and a wet-ear group （n= 42）.Univariate analysis and binary logistic regression were used to identify risk factors for wet ear status. Postoperative outcomes, including tympanic meoombrane healing rate and hearing improvement across frequencies, were compared between groups. Results:①Significant intergroup differences were observed in age, residual tympanic membrane status, external auditory canal condition, mastoid pneumatization（MC0）, and middle ear ventilation dysfunction（P<0.05）; ②The degree of mastoid pneumatization being MC0 is an independent risk factor for wet ear（P<0.05）; ③No significant difference in tympanic membrane healing rates was found（P>0.05）; ④The wet ear group showed significantly higher pre-and postoperative air-conduction（AC） and bone-conduction（BC） thresholds at 2 kHz and 4 kHz compared to the dry ear group（P<0.05）, though the postoperative air-bone gap（ABG） improvement was comparable. Conclusion:Poor mastoid pneumatization is a risk factor for wet ears. The wet ear state has no effect on tympanic membrane healing and air-bone conduction gap, but patients in the wet ear group may have more severe inner ear or auditory nerve pathway damage.
Humans ; Retrospective Studies ; Tympanoplasty/methods* ; Adult ; Risk Factors ; Male ; Female ; Young Adult ; Endoscopy ; Adolescent ; Middle Aged ; Treatment Outcome ; Child ; Logistic Models ; Tympanic Membrane/surgery*

OBJECTIVE: The objective of this study was to analyse fungal composition and exploit application potential in the Bantou (BT) agarwood-forming trunk of Aquilaria sinensis. METHODS: BT agarwood is a naturally formed agarwood that was collected after cutting. Total genomic DNA of the fungi in BT agarwood was extracted by the hexadecyltrimethy ammonium bromide (CTAB) method, followed by PCR amplification and library construction. The effective tags were obtained by the HiSeq2500 platform, and the data were subjected to bioinformatics and statistical analyses. RESULTS: A total of 7 850 040 effective tags were obtained, Ascomycota was the most abundant fungus at the phylum level, with a relative abundance of 56.36%-61.44%, followed by Basidiomycota, with a relative abundance of 10.49%-20.39%. Dothideomycetes, Agaricomycetes and Sordariomycetes were dominant at the class level, accounting for 26.21%-33.88%, 8.40%-17.66%, and 18.41%-24.11%, respectively. Lignosphaeria, Phaeoacremonium and Hermatomyces were dominant at the genus level, with relative abundances of 6.25%-7.64%, 1.95%-9.05% and 1.5%-5.4%, respectively. Diversity and richness analysis showed that the fungal composition in the agarwood formation sites (agarwood layer, upper agarwood layer and lower agarwood layer) were significantly lower than those in the decomposing layer and the healthy layer. That is, the fungal diversity and richness were significantly reduced during agarwood formation by the action of open wounds. The fungal community structure in the decomposing layer and agarwood formation sites obviously differed from that in the healthy layer. The number of Aspergillus taxa in agarwood formation sites decreased significantly (healthy layer is 0.5%, decomposing layer is 0.022%, upper agarwood layer is 0.012%, agarwood layer is 0.01%, and lower agarwood layer is 0.013%), indicating that agarwood may contain potential substances to inhibit the growth of Aspergillus. CONCLUSION Agarwood from agarwood formation sites contains potential substances that inhibit Aspergillus, which provides valuable information for the control of the genus of Aspergillus.

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Background Industrial emissions are a well-established major source of urban fine particulate matter (PM_2.5) and associated heavy metals. To improve local air quality, Shanghai No. 1 Iron and Steel Plant in Baoshan District was entirely relocated, with all production lines successively shut down in 2018. Objective To evaluate the trends in PM_2.5 and three heavy metal concentrations - chromium (Cr), mercury (Hg), and thallium (Tl) —in the local atmosphere pre- and post- relocation of the steel plant. Methods Taking the steel plant relocation in 2019 as the intervention cutoff point, this study was divided into two phases: pre-intervention (January 2017 to December 2018) and post-intervention (January 2019 to December 2021). Monthly mean pollutant concentrations were used to construct an interrupted time series (ITS) model, followed by segmented linear regression to assess the pre- and post-intervention trends in ambient PM_2.5 and three heavy metals surrounding thesteel plant. Results The ITS regression analysis revealed that the change in PM_2.5 concentration (b₂) after the intervention was −7.16 μg·m⁻³, while the changes in Cr, Hg, and Tl concentrations (b₂) were −0.46, −0.03, and −0.06 ng·m⁻³, respectively. Prior to the intervention, PM_2.5 mass concentrations exhibited a temporal decline with a slope of b₁ = –0.69 (P<0.05); seasonal adjustment further strengthened the overall significance of the model. Before the intervention, the concentration of Cr increased over time, with a slope of b₁=0.12 (P<0.05). After the intervention, the concentration of Cr showed a gradual downward trend over time, with a slope (b₁ + b₃) of −0.04, and significant seasonal variations were observed. The concentration of Hg decreased over time before the intervention, with a slope of b₁=−0.0029 (P<0.05). After the intervention, the slope was −0.0003, showing a further slow decline in Hg concentration over time. However, no significant seasonal trend was observed for Hg. The mass concentration of Tl decreased after the intervention, and the difference before and after the intervention was statistically significant (P<0.05). PM_2.5, Cr, and Tl better fit to the seasonal model, whereas Hg showed a better fit to the non-seasonal model. Conclusion The steel plant relocation intervention has markedly improved local air quality.