Objective:To evaluate the efficacy and immunological mechanisms of pegylated interferon α-2b (Peg-IFNα-2b) antiviral therapy in treatment-naive patients with chronic hepatitis B(CHB).Methods:A total of 166 treatment-naive CHB patients, who were treated at Department of Infectious Diseases, the Second Affiliated Hospital of Nanchang University from March 2021 to March 2023, were enrolled in this study. All the patients received Peg-IFNα-2b therapy for 48 weeks. Serum hepatitis B virus (HBV) DNA, HBV serological markers, biochemical parameters, peripheral blood lymphocyte subsets and serum cytokine levels were detected and compared before and after treatment. Chi-square test, Mann-Whitney U test and paired sample t test were used for statistical comparison. Multivariate logistic regression analysis was used to analyze the influencing factors of hepatitis B surface antigen (HBsAg) seroconversion by stepwise regression method, and the receiver operator characteristic curve (ROC curve) was used to evaluate the predictive efficacy of immune indicators on HBsAg seroconversion. Results:Among the 166 treatment-naive CHB patients, the rate of HBV DNA negativity following 48 weeks of Peg-IFNα-2b therapy was 71.08%(118/166), the rate of hepatitis B e antigen (HBeAg) negativity was 32.05%(25/78), and the rate of HBsAg negativity was 20.48%(34/166). HBsAg negativity rate was 52.17%(24/46) in patients with baseline HBsAg<200 IU/mL, 10.26%(4/39) in patients with baseline HBsAg 200 to <1 200 IU/mL, and 7.41%(6/81) in patients with baseline HBsAg≥1 200 IU/mL, and the difference was statistically significant( χ2=39.37, P<0.001). After 48 weeks of treatment, serum levels of alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBil), and alpha-fetoprotein (AFP) were significantly lower than those before treatment ( Z=9.33, 8.58, 5.99, 2.36, respectively, all P<0.05). lmmune indicators were detected in 58 patients, and the proportion of peripheral blood lymphocytes increased significantly post-treatment, with notable increases in CD3 + CD8 + T/CD3 + T, CD3 + CD4 + DR + /CD3 + CD4 + , CD3 + CD8 + DR + /CD3 + CD8 + , CD3 + CD8 + CD38 + /CD3 + CD8 + , CD3 + CD8 + CD28 + /CD3 + CD8 + , and CD19 + B cells, and the differences were all statistically significant ( t=-2.56, t=-8.65, Z=-3.58, t=-3.66, Z=-3.04, t=-3.62, t=-3.87, respectively, all P<0.05). Conversely, the proportion of CD3 + , CD3 + CD4 + T/CD3 + T, CD3 + CD4 + CD45RO + /CD3 + CD4 + , CD3 + CD8 + CD45RO + /CD3 + CD8 + and the CD4 + /CD8 + ratio decreased significantly post-treatment ( t=3.13, t=5.61, t=3.69, Z=3.95, Z=7.33, respectively, all P<0.05). No significant differences were observed in the proportion of CD16 + CD56 + natural killer (NK) cells, CD3 + CD4 + CD28 + /CD3 + CD4 + , CD3 + CD4 + CD38 + /CD3 + CD4 + cells before and after treatment (all P>0.05). Serum levels of interleukin(IL)-8, IL-12P70, and IL-17 significantly decreased post-treatment ( Z=2.85, 3.26, 4.12, respectively, all P<0.05), while IL-2, IL-1β, and interferon(IFN)-α levels were significantly elevated compared to baseline ( Z=-4.92, -4.85, -9.01, respectively, all P<0.001). There were no significant differences in IL-4, IL-6, and IL-10 levels before and after treatment (all P>0.05). Logistic regression analysis identified CD3 + CD8 + T/CD3 + T(odd ratios ( OR)=1.198, 95%confidence interval( CI) 1.003 to 1.432, P=0.046), CD3 + CD4 + DR + /CD3 + CD4 + ( OR=1.185, 95% CI 1.035 to 1.357, P=0.014), CD3 + CD8 + DR + /CD3 + CD8 + ( OR=0.813, 95% CI 0.690 to 0.958, P=0.013), CD3 + CD4 + CD38 + /CD3 + CD4 + ( OR=0.678, 95% CI 0.488 to 0.940, P=0.020), CD3 + CD8 + CD38 + /CD3 + CD8 + ( OR=1.272, 95% CI 1.069 to 1.512, P=0.007), CD19 + B cells( OR=0.752, 95% CI 0.582 to 0.971, P=0.029), IL-2( OR=8.568, 95% CI 1.927 to 38.087, P=0.005), and IL-17( OR=0.728, 95% CI 0.535 to 0.989, P=0.042) as independent factors influencing HBsAg seroconversion. The area under the curve (AUC) of the proportion of dCD19 + B cells (the reciprocal of CD19 + B cells) for predicting HBsAg seroconversion was 0.716, the sensitivity was 0.636, and the specificity was 0.809. The AUC of IL-2 was 0.657, the sensitivity was 0.818, and the specificity was 0.404. The AUC of dIL-17 (the reciprocal of IL-17 levels) was 0.624, the sensitivity was 0.727, and the specificity was 0.489. The AUC of IL-2 and dIL-17 as a combined predictor was 0.830, the sensitivity was 0.909, and the specificity was 0.787. Conclusions:Peg-IFNα-2b demonstrates significant antiviral, biochemical, and serological responses in treatment-naive CHB patients, with enhanced efficacy in patients exhibiting HBsAg levels <200 IU/mL. In patients with HBsAg<200 IU/mL, the rate of HBsAg negativity reached 52.17%.Peg-IFNα-2b can regulate the immune function of patients with CHB by increasing the proportion of activated T lymphocyte subsets and functional subsets. The proportion of CD19 + B cells, IL-2 levels, and IL-17 levels hold predictive value for achieving HBsAg seroconversion.

Objective:To evaluate the efficacy and immunological mechanisms of pegylated interferon α-2b (Peg-IFNα-2b) antiviral therapy in treatment-naive patients with chronic hepatitis B(CHB).Methods:A total of 166 treatment-naive CHB patients, who were treated at Department of Infectious Diseases, the Second Affiliated Hospital of Nanchang University from March 2021 to March 2023, were enrolled in this study. All the patients received Peg-IFNα-2b therapy for 48 weeks. Serum hepatitis B virus (HBV) DNA, HBV serological markers, biochemical parameters, peripheral blood lymphocyte subsets and serum cytokine levels were detected and compared before and after treatment. Chi-square test, Mann-Whitney U test and paired sample t test were used for statistical comparison. Multivariate logistic regression analysis was used to analyze the influencing factors of hepatitis B surface antigen (HBsAg) seroconversion by stepwise regression method, and the receiver operator characteristic curve (ROC curve) was used to evaluate the predictive efficacy of immune indicators on HBsAg seroconversion. Results:Among the 166 treatment-naive CHB patients, the rate of HBV DNA negativity following 48 weeks of Peg-IFNα-2b therapy was 71.08%(118/166), the rate of hepatitis B e antigen (HBeAg) negativity was 32.05%(25/78), and the rate of HBsAg negativity was 20.48%(34/166). HBsAg negativity rate was 52.17%(24/46) in patients with baseline HBsAg<200 IU/mL, 10.26%(4/39) in patients with baseline HBsAg 200 to <1 200 IU/mL, and 7.41%(6/81) in patients with baseline HBsAg≥1 200 IU/mL, and the difference was statistically significant( χ2=39.37, P<0.001). After 48 weeks of treatment, serum levels of alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBil), and alpha-fetoprotein (AFP) were significantly lower than those before treatment ( Z=9.33, 8.58, 5.99, 2.36, respectively, all P<0.05). lmmune indicators were detected in 58 patients, and the proportion of peripheral blood lymphocytes increased significantly post-treatment, with notable increases in CD3 + CD8 + T/CD3 + T, CD3 + CD4 + DR + /CD3 + CD4 + , CD3 + CD8 + DR + /CD3 + CD8 + , CD3 + CD8 + CD38 + /CD3 + CD8 + , CD3 + CD8 + CD28 + /CD3 + CD8 + , and CD19 + B cells, and the differences were all statistically significant ( t=-2.56, t=-8.65, Z=-3.58, t=-3.66, Z=-3.04, t=-3.62, t=-3.87, respectively, all P<0.05). Conversely, the proportion of CD3 + , CD3 + CD4 + T/CD3 + T, CD3 + CD4 + CD45RO + /CD3 + CD4 + , CD3 + CD8 + CD45RO + /CD3 + CD8 + and the CD4 + /CD8 + ratio decreased significantly post-treatment ( t=3.13, t=5.61, t=3.69, Z=3.95, Z=7.33, respectively, all P<0.05). No significant differences were observed in the proportion of CD16 + CD56 + natural killer (NK) cells, CD3 + CD4 + CD28 + /CD3 + CD4 + , CD3 + CD4 + CD38 + /CD3 + CD4 + cells before and after treatment (all P>0.05). Serum levels of interleukin(IL)-8, IL-12P70, and IL-17 significantly decreased post-treatment ( Z=2.85, 3.26, 4.12, respectively, all P<0.05), while IL-2, IL-1β, and interferon(IFN)-α levels were significantly elevated compared to baseline ( Z=-4.92, -4.85, -9.01, respectively, all P<0.001). There were no significant differences in IL-4, IL-6, and IL-10 levels before and after treatment (all P>0.05). Logistic regression analysis identified CD3 + CD8 + T/CD3 + T(odd ratios ( OR)=1.198, 95%confidence interval( CI) 1.003 to 1.432, P=0.046), CD3 + CD4 + DR + /CD3 + CD4 + ( OR=1.185, 95% CI 1.035 to 1.357, P=0.014), CD3 + CD8 + DR + /CD3 + CD8 + ( OR=0.813, 95% CI 0.690 to 0.958, P=0.013), CD3 + CD4 + CD38 + /CD3 + CD4 + ( OR=0.678, 95% CI 0.488 to 0.940, P=0.020), CD3 + CD8 + CD38 + /CD3 + CD8 + ( OR=1.272, 95% CI 1.069 to 1.512, P=0.007), CD19 + B cells( OR=0.752, 95% CI 0.582 to 0.971, P=0.029), IL-2( OR=8.568, 95% CI 1.927 to 38.087, P=0.005), and IL-17( OR=0.728, 95% CI 0.535 to 0.989, P=0.042) as independent factors influencing HBsAg seroconversion. The area under the curve (AUC) of the proportion of dCD19 + B cells (the reciprocal of CD19 + B cells) for predicting HBsAg seroconversion was 0.716, the sensitivity was 0.636, and the specificity was 0.809. The AUC of IL-2 was 0.657, the sensitivity was 0.818, and the specificity was 0.404. The AUC of dIL-17 (the reciprocal of IL-17 levels) was 0.624, the sensitivity was 0.727, and the specificity was 0.489. The AUC of IL-2 and dIL-17 as a combined predictor was 0.830, the sensitivity was 0.909, and the specificity was 0.787. Conclusions:Peg-IFNα-2b demonstrates significant antiviral, biochemical, and serological responses in treatment-naive CHB patients, with enhanced efficacy in patients exhibiting HBsAg levels <200 IU/mL. In patients with HBsAg<200 IU/mL, the rate of HBsAg negativity reached 52.17%.Peg-IFNα-2b can regulate the immune function of patients with CHB by increasing the proportion of activated T lymphocyte subsets and functional subsets. The proportion of CD19 + B cells, IL-2 levels, and IL-17 levels hold predictive value for achieving HBsAg seroconversion.

Objective To explore the effect of sling exercise with Tuina therapy on kinesiophobia in old patients with lumbar disc herniation,and analyze the mechanism based on brain-bone axis. Methods A total of 56 old patients with chronic lumbar disc herniation and kinesiophobia were selected from the Reha-bilitation Hospital of the Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine from September,2022 to December,2023;and randomly divided into control group(n=28)and experimental group(n=28).The control group accepted conventional exercise therapy,while the experimental group accepted sling exercise with Tuina therapy,for four weeks.They were assessed with simplified Chinese version of Tampa Scale of Kinesiophobia(TSK),Japanese Orthopaedic Association score(JOA)and Visual Analogue Scale for pain(VAS)before and after treatment,while the bone mineral density(BMD)was tested,the levels of osteoprote-gerin(OPG),norepinephrine(NE)and corticosteroids(Cor)in serum were measured,and the median frequency(MF)of weak-link erector spinae was detected with surface electromyography. Results Two cases dropped off in the control group,and one in the experimental group.The scores of all the assessment improved in both groups after treatment(|t|>14.168,P<0.001),as well as the serum levels of OPG,NE and Cor(|t|>2.103,P<0.05),BMD(|t|>2.726,P<0.05),and MF of erector spinae(|t|>14.736,P<0.001);all of them were better in the experimental group than in the control group(|t|>2.154,P<0.05). Conclusion Sling exercise with Tuina therapy can improve the pain and kinesiophobia of lumbar disc herniation in the old adults,which may promote the recovery of physical and mental function through regulating the levels of hor-mones and neurotransmitters related to the brain-bone axis.

Objective To observe the effectiveness of the three-dimensional balanced chiropractic technique in the treatment of lumbar disc herniation (LDH) and analyze predictive factors for resorption of the herniated nucleus pulposus based on magnetic resonance imaging (MRI). Methods From June 2015 to June 2021, 95 patients with LDH treated with the three-dimensional balanced chiropractic techniquein our hospital were followed up for clinical and MRI data. They were divided into resorption group and non-resorption group based on the nucleus pulposus resorption rate. Multivariable binary logistic regression analysis was performed to determine the association of 12 factors (sex, age, course of disease, etc.)with nucleus pulposus resorption. Results Thirty-two cases (33.7%)were found at follow-up to have nucleus pulposus resorption (resorption rate≥30%). Resorption was most likely to occur in patients with a disease course of less than a year (P < 0.001), type 3 LDH accoding to the Michigan State University (MSU) classification (P = 0.014), leg numbness (P = 0.006), and a L4/5 or L5/S1 disc herniation (P < 0.001). Conclusion MRI can be used as an important tool to observe nucleus pulposus resorption in LDH. A disease course of less than a year, MSU type 3, leg numbness, a L4/5 or L5/S1 disc herniation are associated with a higher possibility of nucleus pulposus resorption, which can be used as indicators predicting the outcome of patients with LDH treated with the three-dimensional balanced chiropractic technique.

Objective:To investigate the interventional effect of metformin on pulmonary inflammation and pulmonary fibrosis in silicotic rats.Methods:In April 2019, 48 Wistar male rats of SPF grade were randomly divided into negative control group, metformin control group, silicon dioxide (SiO 2) model group, low, medium and high dose metformin intervention group according to the random number table method, 8 rats in each group. The SiO 2 model group and the low, medium and high dose metformin intervention groups were given 1 ml 50 mg/ml of SiO 2 by intratracheal instillation, the negative control group and the metformin control group were given 1 ml normal saline by intratracheal instillation. 24 hours later, the low, medium and high dose metformin intervention groups and the metformin control group were treated with 100, 200, 400 and 400 mg/kg metformin daily, the control and SiO 2 model groups received normal saline daily. Then the rats were sacrificed at the 28th day after SiO 2 exposure. The changes of rat body weight and pathological examination of rat lung tissue were observed, and the lung organ coefficient, the content of hydroxyproline (HYP) , the expression levels of inflammatory factors transforming growth factor beta1 (TGF-β1) , tumor necrosis factor-alpha (TNF-α) , interleukin-1beta (IL-1β) and the protein expression of E-cadherin (E-Cad) , Vimentin, α-SMA were detected. Results:Compared with the negative control group, SiO 2 model group had a significant decrease in the body weight of rats ( P<0.05) , lung organ coefficient, alveolitis and fibrosis scores, HYP content and the levels of TGF-β1, TNF-α, IL-1β were all significantly increased ( P<0.05) . Compared with the SiO 2 model group, the weights of the rats in the medium and high dose intervention group of metformin increased significantly ( P<0.05) . And after intervention with different doses of metformin, the lung organ coefficient, alveolitis and fibrosis scores, HYP content and the levels of TGF-β1, TNF-α and IL-1β were significantly decreased ( P<0.05) . Immunohistochemistry and Western blotting results showed that compared with the negative control group, the expression of E-Cad of the SiO 2 model group was decreased, and the expression levels of Vimentin and α-SMA were significantly increased ( P<0.05) . After metformin intervention, the expression of E-Cad was significantly increased, the expression levels of Vimentin and α-SMA were significantly decreased ( P<0.05) . Conclusion:Metformin can reduce lung tissue inflammation and fibrosis in rats exposed to SiO 2 dust, which may be related to reducing the expression of inflammatory factors in lung tissue and inhibiting the EMT process.

Objective:To investigate the interventional effect of metformin on pulmonary inflammation and pulmonary fibrosis in silicotic rats.Methods:In April 2019, 48 Wistar male rats of SPF grade were randomly divided into negative control group, metformin control group, silicon dioxide (SiO 2) model group, low, medium and high dose metformin intervention group according to the random number table method, 8 rats in each group. The SiO 2 model group and the low, medium and high dose metformin intervention groups were given 1 ml 50 mg/ml of SiO 2 by intratracheal instillation, the negative control group and the metformin control group were given 1 ml normal saline by intratracheal instillation. 24 hours later, the low, medium and high dose metformin intervention groups and the metformin control group were treated with 100, 200, 400 and 400 mg/kg metformin daily, the control and SiO 2 model groups received normal saline daily. Then the rats were sacrificed at the 28th day after SiO 2 exposure. The changes of rat body weight and pathological examination of rat lung tissue were observed, and the lung organ coefficient, the content of hydroxyproline (HYP) , the expression levels of inflammatory factors transforming growth factor beta1 (TGF-β1) , tumor necrosis factor-alpha (TNF-α) , interleukin-1beta (IL-1β) and the protein expression of E-cadherin (E-Cad) , Vimentin, α-SMA were detected. Results:Compared with the negative control group, SiO 2 model group had a significant decrease in the body weight of rats ( P<0.05) , lung organ coefficient, alveolitis and fibrosis scores, HYP content and the levels of TGF-β1, TNF-α, IL-1β were all significantly increased ( P<0.05) . Compared with the SiO 2 model group, the weights of the rats in the medium and high dose intervention group of metformin increased significantly ( P<0.05) . And after intervention with different doses of metformin, the lung organ coefficient, alveolitis and fibrosis scores, HYP content and the levels of TGF-β1, TNF-α and IL-1β were significantly decreased ( P<0.05) . Immunohistochemistry and Western blotting results showed that compared with the negative control group, the expression of E-Cad of the SiO 2 model group was decreased, and the expression levels of Vimentin and α-SMA were significantly increased ( P<0.05) . After metformin intervention, the expression of E-Cad was significantly increased, the expression levels of Vimentin and α-SMA were significantly decreased ( P<0.05) . Conclusion:Metformin can reduce lung tissue inflammation and fibrosis in rats exposed to SiO 2 dust, which may be related to reducing the expression of inflammatory factors in lung tissue and inhibiting the EMT process.

OBJECTIVE: To investigate the effect of toluene diisocyanate(TDI) on the activation of autophagy and expression of inflammatory cytokines interleukin(IL)-4 and IL-6 in normal human bronchial epithelial cells(16 HBE). METHODS: i) We prepared TDI-human serum albumin(HSA) and determined the mass concentration of TDI in TDI-HSA. ii) The cells were treated with TDI-HSA and HSA at concentrations of 0.00-400.00 mg/L for 12 hours. CCK-8 assay was used to determinate the cell viability, and TDI-HSA and HSA doses were selected for subsequent experiments. iii) The cells were treated with TDI-HSA and HSA at doses of 0.00-120.00 mg/L for 12 hours, and the levels of reactive oxygen species(ROS) in the cells were detected by flow cytometry. The levels of IL-4 and IL-6 in the cell supernatant were measured by enzyme-linked immunosorbent assay. iv) The cells were treated with TDI-HSA at doses of 0.00-120.00 mg/L for 12 hours, and the autophagy activity was observed under transmission electron microscope. Western blot was utilized to detect the expression of Beclin1, microtubule-associated protein 1 light chain(LC3β) and P62. RESULTS: i) The mass concentrations of TDI in 40.00, 80.00 and 120.00 mg/L TDI-HSA groups were 0.44, 0.89 and 1.33 mg/L respectively. ii) The results of CCK-8 showed that TDI-HSA and HSA at doses below 120.00 mg/L did not affect cell viability, and 0.00-120.00 mg/L was selected as the TDI-HSA and HSA treatment doses for subsequent experiments. iii) The level of ROS in cells and the levels of IL-4 and IL-6 in the supernatant of 16 HBE cells in the TDI-HSA group at 40.00, 80.00, and 120.00 mg/L were higher than that in HSA group at the same dose(P<0.01). The level of ROS in cells and the levels of IL-4 and IL-6 in the supernatant of 16 HBE cells increased with the increase of TDI-HSA doses(P<0.01). iv) Transmission electron microscopy showed that the number of autophagic lysosomes in 16 HBE cells increased significantly, and the number of mitochondrial vacuoles increased in 40.00, 80.00, 120.00 mg/L TDI-HSA group compared with 0.00 mg/L group. With the increase of TDI-HSA dose, the relative expression of Beclin1 protein and LC3β-Ⅱ/Ⅰ ratio in 16 HBE cell supernatant increased(P<0.05), and the relative expression of P62 protein decreased(P<0.05). CONCLUSION: TDI-HSA induces increased expression of ROS and inflammatory factors and induces autophagy activation in 16 HBE cells. Autophagy may be an important factor for the development of airway inflammation in TDI-induced occupational asthma.

OBJECTIVE: To explore the effect of reactive oxygen species(ROS) and cell cycle in bone marrow cells in benzene-induced aplastic anemia(AA) mouse model. METHODS: Specific pathogens free male CD1 mice were randomly divided into control group and exposure group(n=10, each group). The mice in exposure group were subcutaneously injected with benzene at a dose of 2 mL/kg body weigh diluted 1 ∶1 in corn oil, while the mice in control group were treated with equal volume of corn oil, 3 times a week for a total of 25 times. After exposure, the blood routine and reticulocyte percentage of peripheral blood of mice were examined. The femur histopathology was performed. The levels of benzene and its metabolites hydroquinone, and phenol in blood, liver and bone marrow were tested by solid-phase extraction gas chromatography mass spectrometry. The level of ROS and the changes of cell cycle in bone marrow mononuclear cells(BMMNCs) were determined by flow cytometry. The protein expression of Cyclin D1 and cyclin-dependent kinase 4(CDK4) in BMMNCs was detected by Western blot. RESULTS: Since the 10 th benzene exposure, the body mass of mice in the exposure group was lower than that in the control group at the same time point(P<0.05). After the benzene exposure, all the counts of white blood cell, red blood cell, platelet, and hemoglobin level and reticulocyte percentage in peripheral blood of mice in the exposure group were decreased when compared with the control group(P<0.05). Bone marrow histopathological examination showed that bone marrow hematopoietic cells were decreased and non-hematopoietic cells were increased in the exposure group. In this study, a mouse model of AA induced by benzene was successfully established. The levels of benzene, hydroquinone and phenol in exposure group increased in blood, liver, and bone marrow compared to control group(P<0.05). Furthermore, the level of benzene from high to low were blood, liver and bone marrow, while the levels of hydroquinone and phenol were mainly stored in the blood and bone marrow in exposure group. Compared with the control group, the level of ROS, S phase fraction, and the relative protein expression of Cyclin D1 and CDK4 in BMMNCs increased, while the G1 phase fraction decreased in exposure group(P<0.01). CONCLUSION: The results suggest that benzene and its metabolites induce an increase of ROS level and S phase cell arrest, that play an important role in the pathogenesis and development of benzene-induced AA.

Objective: To screen the changes of microRNA (miRNA) expression profiles in lung tissues of early silicosis rats, and provide a basis for functional analysis of differential microRNA. Methods: SPF Wistar male rats were randomly divided into a negative control group and SiO₂-exposed groups, with 30 rats in each group. The model of silicosis in rats was established by intratracheal instillation of 1 ml SiO₂ suspension, and the control rats were treated with 1mL in the same way to sterilize normal saline. The lung tissues of two group were collected at the 1, 7, 14, 21, 28 d after SiO₂-exposed. Three of the rat lung tissues were used for pathological observation, and the other three were used to screen differentially expressed miRNAs in lung tissue by miRNA microarray technology. miRNA chip screening and RT-qPCR were used to verify the expression levels of miRNA-423-5p and miRNA-26a-5p in the two groups. miRNA-423-5p and miRNA-26a-5p are predicted by target genes and analyzed by GO (gene ontology) enrichment analysis and KEGG (kyoto encyclopedia of genes and genomes) pathway analysis. Results: In the control group, the inflammatory response of lung tissue 21 and 28 days was significantly reduced compared with 1, 7 and 14 days, and the inflammatory cells infiltrated in the lung tissue of the SiO₂-exposed rats. The rats in the control group had a small amount of collagen at 21 and 28 days, but a large amount of collagen fiber deposition began to appear in the lung tissue of rats exposed to SiO₂ after 21 days. Compared with the control group, the expression levels of micro RNA-423-5p was significantly up-regulated and the expression of microRNA-26a-5p was significantly down-regulated in the SiO₂-exposed rats lung tissues dust at different time points (P<0.05) . Conclusion The up-regulation of miRNA-423-5p and the down-regulation of miRNA-26a-5p in lung tissues of early silicotic rats may be related to the occurrence and development of early silicosis.

Objective: To investigate the role of microRNA-29b-3p (miRNA-29b-3p) and miRNA-34c-3p in the process of pulmonary fibrosis, we detected the expression levels of miRNA-29b-3p and miRNA-34c-3p in the lung tissue of rats exposed to silica and A549 cells. Methods: SPF male Wistar rats were randomly divided into 1, 7, 14, 21, 28 d control group and silica (SiO₂) dusting group, with 6 rats in each group. One-time non-exposure method was used to infuse 1ml SiO₂ suspension. The rat SiO₂ dusting group was established in the liquid, and the control rats were intratracheally injected with 1 ml of sterile physiological saline in the same manner. The lung tissues of each group were collected at the corresponding time points after dusting. Three of the rats were taken out for pathological observation, and the other three were used to screen differentially expressed miRNAs in lung tissue by miRNA microarray technology. A549 cells were cultured at the in vitro cell level and divided into control group, SiO₂ stimulation group and TGF-β₁ stimulation group, and cells were collected at 12, 24 and 48 h after treatment. The expression levels of miRNA-29b-3p and miRNA-34c-3p in rat lung tissue and A549 cells were verified by real-time PCR (qRT-PCR), target gene prediction of miRNA-29b-3p and miRNA-34c-3p and perform GO enrichment analysis and KEGG pathway analysis. Results: The weight growth rate of the control group was significantly higher than that of the SiO₂ dusting group. Compared with the control group, the lung mass and lung coefficient of the SiO₂ dusting group were significantly increased (P<0.05). The inflammatory response of the lungs in the control group was significantly reduced at 21 and 28 days, and the inflammatory cells infiltrated in the lung tissue of the SiO2 group. The rats in the control group had a small amount of collagen at 21 and 28 days. A large amount of collagen fiber deposition began to appear in the lung tissue of rats exposed to SiO₂ for 21 days. Compared with the control group, the expression levels of miRNA-29b-3p and miRNA-34c-3p in the SiO₂ dusting group were significantly down-regulated, and there was significant difference compared with the control group (P<0.05). The expression levels of miRNA-29b-3p and miRNA-34c-3p in A549 cells treated with SiO₂ and human recombinant TGF-β1 were significantly lower than those in the control group at 24 h and 48 h, and the difference was statistically significant (P<0.05). Conclusion Down-regulation of miRNA-29b-3p and miR-34c-3p in rat lung tissue A549 cells may be associated with the development of early silicosis and is expected to be an indicator of early silicosis diagnosis and prognosis.