ObjectiveTo investigate the effects and potential mechanisms of Tongmai Yangxin Pills （通脉养心丸） （TYPs） in preventing ischemia-reperfusion （I/R）-induced arrhythmia. MethodsSixty male SD rats were randomly assigned to sham operation group， model group， amiodarone group， low-dose and high-dose TYPs group， with 12 rats in each group. The sham operation group and the model group received 10 g/（kg·d） normal saline by gavage， the amiodarone group received 60 mg/（kg·d） amiodarone， and the low-dose and high-dose TMP groups received 1 g/（kg·d） and 2 g/（kg·d） TYPs solution respectively， for 21 days， administered twice daily. On the day after the last administration， the I/R model was established in the model and medication groups by ligation of the left anterior descending coronary artery with a cannula， while the sham operation group underwent the same procedure without ligation. Electrocardiogram recordings were continuously monitored throughout the modeling process. Heart rate was recorded at five time points， before ischemia （t-0）， 5-10 min after ischemia （t-1）， 10-15 min after ischemia （t-2）， 15-30 min after ischemia （t-3）， and during the first 2 min of reperfusion （t-4）； the incidence of arrhythmia including ventricular premature beats （VPB）， ventricular tachycardia （VT）， and ventricular fibrillation （VF） was recorded； arrhythmia scores were calculated. After 24 hours of reperfusion， left ventricular myocardial tissue was collected. Hematoxylin-eosin （HE） staining was performed to observe pathological changes. RT-PCR was used to detect the mRNA expression of microRNA-1 （miRNA-1）， microRNA-133a （miRNA-133a）， and potassium （K⁺） and calcium （Ca²⁺） ion channel-related genes including KCND2， KCNH2， KCNE2， KCNQ1， KCNE1， KCNJ2， CACNA1C， and CACNB1. Western blot analysis was used to measure protein levels of transient outward potassium current protein （Kv4.2）， rapidly activating delayed rectifier potassium current protein （HERG）， slowly activating delayed rectifier potassium current protein （KvLQT1）， inward rectifier potassium current protein （Kir2.1）， and L-type calcium channel protein （Cav1.2）. ResultsCompared with sham operation group， the model group showed diffuse myocardial hemorrhage， inflammatory cell infiltration， myocardial necrosis， nuclear pyknosis， vacuolar degeneration， and disrupted myocardial fibers； the model group also exhibited a decreased heart rate （t-1 to t-4）， increased arrhythmia scores， elevated miRNA-1 and miRNA-133a expression， and decreased mRNA expression of KCND2， KCNH2， KCNE2， KCNQ1， KCNE1， KCNJ2， CACNA1C， and CACNB1 in myocardial tissue； additionally， Kv4.2， HERG， KvLQT1， Kir2.1， and Cav1.2 protein levels significantly reduced （P＜0.01）. Compared to the model group， all medication-treated groups showed reduced myocardial damage， including less hemorrhage， reduced inflammatory infiltration， and improved myocardial structure， with the high-dose TYPs group exhibiting the most significant improvement； the amiodarone group and high-dose TYPs group showed a significant increase in heart rate （t-1 to t-4）， lower arrhythmia scores， reduced miRNA-1 and miRNA-133a expression； the high-dose TYPs group exhibited significantly increased mRNA expression levels of KCND2， KCNH2， KCNQ1， KCNJ2， and CACNA1C， as well as elevated protein levels of Kv4.2， HERG， KvLQT1， Kir2.1， and Cav1.2 （P＜0.05 or P＜0.01）. ConclusionTMPs can improve myocardial damage and reduce the incidence of ventricular arrhythmia in I/R rats. The underlying mechanism may be related to the downregulation of miRNA-1 and miRNA-133a gene expression， as well as the upregulation of K⁺ and Ca²⁺ channel-related genes and proteins.

To investigate the awareness of cognitive impairment disorders among residents of the Xizang Autonomous Region and its influencing factors, thereby providing a basis for targeted prevention and treatment efforts.

ObjectiveTo explore the differences in the accumulation of secondary metabolites of Dendrobium nobile cultivated on epiphytic stones and trees， so as to elucidate the scientific connotation of "only those that grow on stones has superior quality"， and provide a direction for the cultivation and quality evaluation of D. nobile. MethodsUltra-performance liquid chromatography-triple quadrupole/linear ion trap mass spectrometry（UPLC-QTRAP-MS/MS）-based widely targeted metabolomics was used to detect the metabolites of D. nobile cultivated on epiphytic stones and trees. And the combination of principal component analysis（PCA）， hierarchical cluster analysis（HCA）， and orthogonal partial least squares-discriminant analysis（OPLS-DA） was performed for multivariate statistical analysis of metabolites. Differential metabolites were screened by variable importance in the projection（VIP） value≥1 and log₂fold change（FC）≥1 or ≤-1， and Kyoto Encyclopedia of Genes and Genomes（KEGG） enrichment analysis was conducted. ResultsA total of 1 267 metabolites were identified in the stems of D. nobile from the two cultivation modes， dominated by flavonoids（292）， phenolic acids（284）， and alkaloids（189）. Through OPLS-DA screening， 473 differential metabolites were obtained. Compared to epiphytic tree-cultivated D. nobile， epiphytic stone-cultivated D. nobile exhibited upregulation of flavonoids， phenolic acids， alkaloids， lignans and coumarins， while quinones and terpenoids were down-regulated. The differential metabolites mainly included flavonoid glycosides and alkaloids， and these differential metabolites significantly contributed to characterizing the two cultivation patterns. KEGG enrichment analysis revealed significant enrichment in pathways of flavone and flavonol biosynthesis， flavonoid biosynthesis， tyrosine metabolism， and phenylalanine metabolism in epiphytic stone-cultivated D. nobile. ConclusionEpiphytic stone cultivation is beneficial for the accumulation of phenolic acids， flavonoids， and alkaloids in D. nobile， indicating that the "only those that grow on stones has superior quality" documented in the materia medica has certain scientific basis， and the findings also provide a reference for quality evaluation and discrimination research between epiphytic stone and tree cultivated D. nobile.

ObjectiveTo compare colonoscopy compliance rates under different screening strategies, to explore ways to enhance colonoscopy compliance among residents with colorectal carcinoma. MethodsResidents aged between 50‒80 years were recruited through extensive community outreach and voluntary participation. A total of 210 630 residents who participated in the colorectal carcinoma screening program in Jiading District, Shanghai, between 2013 and 2019 were selected as the research subjects. All subjects underwent a colorectal carcinoma risk assessment questionnaire survey and two fecal occult blood tests (FOBT). Positive results in the initial screening were defined as a positive questionnaire survey or a positive result in at least one FOBT. Participants with positive initial screening results were advised to undergo colonoscopy screening in a hospital. Colonoscopy results were collected from hospital reports and physician follow-ups. Compliance with colonoscopy was analyzed under different screening strategies to identify possible factors influencing residents’ willingness to undergo the procedure. ResultsA total of 21 403 individuals (10.16%) were identified as positive with the questionnaire survey, 31 595 individuals (15.00%) tested positive with at least one FOBT. Combined questionnaire and FOBT positivity was observed in 3 501 individuals (1.66%). Among the 48 453 individuals with positive initial screening results, 17 230 (35.56%) underwent colonoscopy, and a total of 315 cases of colorectal cancer were detected. The sensitivity, specificity value of FOBT initial screening were 83.81% and 84.66%, respectively. According to the combined risk assessment and FOBT initial screening preliminary screening, the lowest colonoscopy compliance rate (25.63%) was observed among individuals with only a positive questionnaire, and the highest compliance rate (52.55%) was among those with both positive questionnaire survey and two positive FOBT results. Multivariate analysis revealed that FOBT positivity had the greatest impact on colonoscopy compliance. Those with one positive FOBT test result were 2.64 times more likely to undergo colonoscopy screening than those with negative FOBT results, while individuals with two positive FOBT results were 3.18 times more likely to do so. After adjusting for FOBT results, individuals with positive questionnaire survey results were 1.43 times more likely to undergo colonoscopy screening than those with negative results (95%CI: 1.34‒1.52). Compared to questionnaire-based risk assessment, FOBT results were more influential in determining compliance with colonoscopy. ConclusionThe choice of initial screening method significantly impacts residents’ compliance with colonoscopy. While implementing colorectal carcinoma screening programs, it is necessary to strictly adhere to screening protocols, including risk assessment and FOBT. Additionally, efforts should be made to raise public awareness, encouraging residents to actively participate in risk assessments and FOBT, thereby improving their compliance with colonoscopy.

ObjectiveTo explore the effectiveness of health information dissemination and its influencing factors using the "Shanghai CDC" WeChat public account as a case study, providing references for public health institutions to optimize the use of official new media platforms for effective publicity. MethodsA total of 1 030 headline articles published on the "Shanghai CDC" WeChat public account between 2016 and 2019 were analyzed using content analysis and non-parametric tests to examine the impact of factors such as titles and content categories. ResultsFrom 2016 to 2019, the number of WeChat public account followers increased by 280 000, with the articles accumulating over 8.8 million views. The median (P₂₅, P₇₅) open rate of articles was 5.90% (3.69%, 10.31%), and the median (P₂₅, P₇₅) sharing and forwarding rate was 6.60% (4.25%, 9.17%). Factors such as the use of first- and second-person pronouns, degree adverbs, negative adverbs, explicit viewpoints, and title length all significantly affected the open rate of articles, with OR (95%CI) values of 0.175 (0.041‒0.756), 32.606 (2.350‒452.432), 4.079 (1.093‒15.230), 0.106 (0.028‒0.409), and 1.184 (1.063‒1.319),respectively (all P<0.05). In terms of content, statistical significant differences in dissemination effectiveness were observed across article categories and themes (P<0.05). In terms of article categories, articles related to news hotspots and service information had higher open rates of 9.58% and 14.00%, respectively. These two types of articles also obtained higher sharing and forwarding rates of 7.65% and 9.16%, respectively. In terms of article topics, compared with healthy life and health products, among the top four topics in terms of publication volume, the open rates of articles about infectious diseases and disease-causing biology and immunization programs were higher, accounting for 7.88% and 6.88%, respectively, with no significant difference in sharing and forwarding rates. ConclusionThe "Shanghai CDC" WeChat public account demonstrated good dissemination effectiveness. Enhancing article titles by increasing informational content and degree adverbs (e.g., "highly," "most," and "extremely") and negative adverbs (e.g., "no") can improve dissemination reach. Public health WeChat accounts should incorporate news hotspots or service information in their articles. While maintaining their strengths in disseminating knowledge on infectious diseases and immunization programs, they should also enhance public education in other professional fields within their scope of responsibility to improve the overall dissemination impact of health information.

BackgroundFamily factors are known to play a critical role in the development， progression and prognosis of adolescent patients with depressive disorder. Psychodrama group therapy has the potential for bringing about positive change in individual growth and relationship repair， but there is currently insufficient research evidence for the effectiveness of psychodrama group therapy in promoting the recovery in depressive disorder in adolescents through improving the family parenting skills of their parents. ObjectiveTo explore the influence of psychodrama group therapy based on family parenting intervention on parents of adolescent patients with depressive disorder， so as to provide references for promoting the recovery for adolescent patients with depressive disorder. MethodsPurposive sampling was used to recruit adolescent patients who met the diagnostic criteria for depressive disorder of the International Classification of Diseases， tenth edition （ICD-10） and hospitalized in the psychiatric outpatient department of the First Affiliated Hospital of Chongqing Medical University from October 2023 to March 2024， and their parents （either mother or father） were taken as the study subjects. Psychodrama group therapy based on family parenting intervention was performed once a week for 6 consecutive weeks. After intervention， semi-structured interviews were conducted with parents who participated in the group， and the interviews were recorded. Content analysis method was employed to perform qualitative analysis on the interview recordings and verbatim transcripts. ResultsAfter receiving psychodrama group intervention based on family parenting， parents of adolescent patients with depressive disorder demonstrated improvement in emotional state， enhanced reflective ability and altered coping style， which were specifically manifested as reducing negative emotions， increasing positive emotions， reflecting on themselves， empathizing with others， adjusting cognition， changing the way of stress regulation， improving communication styles and actively seeking resources. ConclusionApplication of psychodrama group therapy based on family parenting intervention may improve emotional state， reflective ability and coping style of the parents of adolescent patients with depressive disorder. ［Funded by Chongqing Education Commission Humanities and Social Science Research Project （number， 19SKGH018）； Chongqing Social Science Planning Project （number， 2021WT29）］

Background Arsenic is an environmentally harmful substance that causes hepatic insulin resistance and liver damage, increasing the risk of type 2 diabetes mellitus. Objective To explore whether the insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) is involved in insulin resistance in HepG2 cells after arsenic exposure through the peroxisome-proliferator-activated receptor γ (PPAR-γ) / glucose transporter 4 (GLUT4) pathway. Methods Cell viability was determined using cell counting kit 8 (CCK8) and an appropriate NaAsO₂ infection dose was determined. A cellular arsenic exposure model of HepG2 cells was established by four concentrations of NaAsO₂ solution for 24 h (the experiment was divided into four groups: 0, 2, 4, and 8 μmol·L⁻¹); HepG2 cells were firstly treated with pcDNA3.1-IGF2BP2 and pcDNA3.1-NC respectively for 6 h, then with 8 μmol·L⁻¹ NaAsO₂ for 24 h to establish a IGF2BP2 overexpression cell model (the experiment was divided into 4 groups: control, NaAsO₂, NaAsO₂+pcDNA3.1-IGF2BP2, and NaAsO₂+pcDNA3.1-NC); finally the cells were subject to 100 nmol·L⁻¹ insulin stimulation for 30 min. Glycogen and glucose in HepG2 cells were determined by glycogen and glucose assay kits; mRNA expression levels of IGF2BP2 were measured by quantitative real-time PCR; protein expression levels of IGF2BP2, PPAR-γ, and GLUT4 in HepG2 were detected by Western blot (WB); and the binding of IGF2BP2 to PPAR-γ and PPAR-γ to GLUT4 was verified by co-immunoprecipitation (CO-IP) experiment. Results The results of CCK8 experiment showed a dose-effect relationship between NaAsO₂ concentration and cell viability. When the concentration of NaAsO₂ was ≥4 μmol·L⁻¹ , the cell viabilities were lower than that of the control group (P <0.05). With the increasing dose of NaAsO₂ infection, reduced glucose consumption and glycogen levels in HepG2 cells were found in the 2, 4, and 8 μmol·L⁻¹ NaAsO₂ treatment groups compared to the control group (P <0.05). The difference between the mRNA expression level of IGF2BP2 in the HepG2 cells treated with 4 or 8 μmol L⁻¹ NaAsO₂ and the control group was significant (P <0.05). In the IGF2BP2 overexpression cell model, compared with the control group, glucose consumption and glycogen levels were lowered in the NaAsO₂ group (P <0.05), the mRNA expression level of IGF2BP2 and the protein expression levels of IGF2BP2, PPAR-γ, and GLUT4 in the cell membrane were all decreased (P <0.05). Compared with the NaAsO₂ group, the glucose consumption and glycogen levels were increased in the NaAsO₂+pcDNA3.1-IGF2BP2 group (P <0.05), and the mRNA expression level of IGF2BP2 and the protein expression levels of IGF2BP2, PPAR-γ, and GLUT4 in the cell membrane were all increased (P <0.05). The results of CO-IP experiments showed that IGF2BP2 interacted with PPAR-γ as well as PPAR-γ with GLUT4 protein. Conclusion IGF2BP2 is involved in arsenic exposure-induced insulin resistance in HepG2 cells by acting on the PPAR-γ/GLUT4 pathway.

ObjectiveTo unveil the mechanism of Jianpi Huogu prescription （JPHGP） in ameliorating the dyslipidemia of steroid-induced osteonecrosis of the femur head （SONFH） by oxylipidomics combined with transcriptomics. MethodsSixty SD rats were assigned into normal， model， low-， medium-， and high-dose （2.5， 5， 10 g·kg^-1， respectively） JPHGP， and Jiangushengwan （1.53 g·kg^-1） groups. Lipopolysaccharide was injected into the tail vein at a dose of 20 μg·kg^-1 on days 1 and 2， and methylprednisolone sodium succinate was injected at a dose of 40 mg·kg^-1 into the buttock muscle on days 3 to 5. The normal group received an equal volume of normal saline. Drug administration by gavage began 4 weeks after the last injection， and samples were taken after administration for 8 weeks. Hematoxylin-eosin staining was conducted to reveal the histopathological changes of the femoral head， and the number of adipocytes， the rate of empty bone lacunae， and the trabecular area were calculated. Micro-computed tomography was used for revealing the histological and histomorphometrical changes of the femoral head. Enzyme-linked immunosorbent assay was employed to measure the serum levels of triglyceride （TG）， total cholesterol （TC）， low-density lipoprotein （LDL）， high-density lipoprotein （HDL）， apolipoprotein A1 （ApoA1）， and apolipoprotein B （ApoB）. At the same time， the femoral head was collected for oxylipidomic and transcriptomic detection. The differential metabolites and differential genes were enriched and analyzed， and the target genes regulating lipid metabolism were predicted. The predicted target proteins were further verified by molecular docking， immunohistochemistry， and Western blot. ResultsCompared with the normal group， the model group showcased thinning of the femoral head， trabecular fracture， karyopyknosis， subchondral cystic degeneration， increases in the number of adipocytes and the rate of empty bone lacunae （P<0.01）， a reduction in the trabecular area （P<0.01）， decreases in BMD， Tb.Th， Tb.N， and BV/TV， and increases in Tb.Sp and BS/BV （P<0.01）. Compared with the model group， the JPHGP groups showed no obvious thinning of the femoral head or subchondroidal cystic degeneration. The high- and medium-dose JPHGP groups presented declines in the number of adipocytes and the rate of empty bone lacunae， an increase in the trabecular area （P<0.05， P<0.01）， rises in BMD， Tb.Th， Tb.N， and BV/TV， and decreases in Tb.Sp and BS/BV （P<0.05， P<0.01）. Compared with the normal group， the model group showcased raised serum levels of TG， TC， LDL， and ApoB and lowered serum levels of HDL and ApoA1 （P<0.01）. Compared with the model group， the JPHGP groups had lowered serum levels of TG， TC， LDL， and ApoB （P<0.05， P<0.01） and a risen serum level of ApoA1 （P<0.05， P<0.01）. Moreover， the serum level of HDL in the high-dose JPHGP group increased （P<0.01）. A total of 19 different metabolites of disease set and drug set were screened out by oxylipidomics of the femoral head， and 119 core genes with restored expression were detected by transcriptomics. The enriched pathways were mainly concentrated in inflammation， lipids， apoptosis， and osteoclast differentiation. Molecular docking， immunohistochemistry， and Western blot results showed that compared with the normal group， the model group displayed increased content of 5-lipoxygenase （5-LO） and peroxisome proliferator-activated receptor γ （PPARγ） in the femoral head （P<0.01）. Compared with the model group， medium- and high-dose JPHGP reduced the content of 5-LO and PPARγ （P<0.05， P<0.01）. ConclusionJPHGP can restore the levels of oxidized lipid metabolites by regulating the 5-LO-PPARγ axis to treat SONFH in rats. Relevant studies provide experimental evidence for the efficacy mechanism of JPHGP in the treatment of SONFH.

ObjectiveTo unveil the mechanism of Jianpi Huogu prescription （JPHGP） in ameliorating the dyslipidemia of steroid-induced osteonecrosis of the femur head （SONFH） by oxylipidomics combined with transcriptomics. MethodsSixty SD rats were assigned into normal， model， low-， medium-， and high-dose （2.5， 5， 10 g·kg^-1， respectively） JPHGP， and Jiangushengwan （1.53 g·kg^-1） groups. Lipopolysaccharide was injected into the tail vein at a dose of 20 μg·kg^-1 on days 1 and 2， and methylprednisolone sodium succinate was injected at a dose of 40 mg·kg^-1 into the buttock muscle on days 3 to 5. The normal group received an equal volume of normal saline. Drug administration by gavage began 4 weeks after the last injection， and samples were taken after administration for 8 weeks. Hematoxylin-eosin staining was conducted to reveal the histopathological changes of the femoral head， and the number of adipocytes， the rate of empty bone lacunae， and the trabecular area were calculated. Micro-computed tomography was used for revealing the histological and histomorphometrical changes of the femoral head. Enzyme-linked immunosorbent assay was employed to measure the serum levels of triglyceride （TG）， total cholesterol （TC）， low-density lipoprotein （LDL）， high-density lipoprotein （HDL）， apolipoprotein A1 （ApoA1）， and apolipoprotein B （ApoB）. At the same time， the femoral head was collected for oxylipidomic and transcriptomic detection. The differential metabolites and differential genes were enriched and analyzed， and the target genes regulating lipid metabolism were predicted. The predicted target proteins were further verified by molecular docking， immunohistochemistry， and Western blot. ResultsCompared with the normal group， the model group showcased thinning of the femoral head， trabecular fracture， karyopyknosis， subchondral cystic degeneration， increases in the number of adipocytes and the rate of empty bone lacunae （P<0.01）， a reduction in the trabecular area （P<0.01）， decreases in BMD， Tb.Th， Tb.N， and BV/TV， and increases in Tb.Sp and BS/BV （P<0.01）. Compared with the model group， the JPHGP groups showed no obvious thinning of the femoral head or subchondroidal cystic degeneration. The high- and medium-dose JPHGP groups presented declines in the number of adipocytes and the rate of empty bone lacunae， an increase in the trabecular area （P<0.05， P<0.01）， rises in BMD， Tb.Th， Tb.N， and BV/TV， and decreases in Tb.Sp and BS/BV （P<0.05， P<0.01）. Compared with the normal group， the model group showcased raised serum levels of TG， TC， LDL， and ApoB and lowered serum levels of HDL and ApoA1 （P<0.01）. Compared with the model group， the JPHGP groups had lowered serum levels of TG， TC， LDL， and ApoB （P<0.05， P<0.01） and a risen serum level of ApoA1 （P<0.05， P<0.01）. Moreover， the serum level of HDL in the high-dose JPHGP group increased （P<0.01）. A total of 19 different metabolites of disease set and drug set were screened out by oxylipidomics of the femoral head， and 119 core genes with restored expression were detected by transcriptomics. The enriched pathways were mainly concentrated in inflammation， lipids， apoptosis， and osteoclast differentiation. Molecular docking， immunohistochemistry， and Western blot results showed that compared with the normal group， the model group displayed increased content of 5-lipoxygenase （5-LO） and peroxisome proliferator-activated receptor γ （PPARγ） in the femoral head （P<0.01）. Compared with the model group， medium- and high-dose JPHGP reduced the content of 5-LO and PPARγ （P<0.05， P<0.01）. ConclusionJPHGP can restore the levels of oxidized lipid metabolites by regulating the 5-LO-PPARγ axis to treat SONFH in rats. Relevant studies provide experimental evidence for the efficacy mechanism of JPHGP in the treatment of SONFH.

Objective To investigate the effects and mechanisms of silica dust on the apoptosis of alveolar epithelial cell (AEC) through in vitro and animal experiments. Methods i) In vitro experiment. A549 cells were stimulated with 100 mg/L silica suspension for 0, 12, 24 and 48 hours. The cell apoptosis rate was detected by flow cytometry. ii) Animal experiment. Specific pathogen-free male C57BL/6 mice were randomly divided into control, 14-day, 28-day, and 56-day groups, with five mice in each group. The mice in the control group were sacrificed at 56 days after being treated with 40.0 μL 0.9% sodium chloride solution, and the mice in the last three groups were sacrificed at 14, 28 and 56 days after being treated with 40.0 μL silica suspension with a mass concentration of 125 g/L via tracheal exposure method. The lung tissues of mice were collected to measure lung organ coefficients. Masson staining was used to detect the degree of pulmonary fibrosis, and Ashcroft scores were evaluated. The apoptosis of AEC in mice was observed by TUNEL immunofluorescence assay. iii) The mRNA relative expression of apoptosis-related genes in A549 cells and mouse lung tissue was detected using reverse transcription and real-time fluorescence quantitative polymerase chain reaction. Results i) In vitro experiment. The apoptosis rate of A549 cells increased with longer silica exposure (all P<0.05). The relative expression of B cell lymphoma-2 (BCL-2) mRNA in A549 cells in 24 h group and 48 h group decreased (both P<0.05), and the relative expression of BCL-2 associated X protein (BAX) mRNA increased (both P<0.05), compared with 0 h group. The mRNA relative expression of caspase (CASP) -3 and CASP-9 in A549 cells increased with longer silica exposure (all P<0.05). ii) Animal experiment. The lung organ coefficients and Ashcroft score in mice progressively increased (all P<0.05), the degree of pulmonary fibrosis was gradually aggravated, and TUNEL positive cells in lung tissue were gradually increased, while Bax, Casp-3 and Casp-9 mRNA relative expression increased with longer silica exposure (all P<0.05). Conclusion Silica dust may cause pulmonary fibrosis by inducing apoptosis of AEC, with a time-dependent effect. The mechanism may be related to the effect of silica dust on mitochondrial apoptosis through Bcl-2/Bax/Caspase-3 signaling pathway.