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Objective To explore the biological exposure limit of blood system damage caused by long-term exposure to polycyclic aromatic hydrocarbons (PAHs) in non-occupational population by using the benchmark dose method, and to provide relevant reference for further improving the assessment of PAHs-induced health damage effects. Methods Adult residents living in downwind direction of a coke-oven plant in Shanxi Province were selected as the research subjects, and the information collected from baseline was used as the control. The metabolites of PAHs in urine were used as exposure biomarker, and the abnormal rate of red blood cell index was used as response biomarker. The relationship between urinary OH-PAHs and the erythrocyte damage rate was analyzed, and the benchmark dose (BMD) and the lower confidence limitation for the benchmark dose (BMDL) were calculated using Bayesian dose-optimizing software. Results The urinary PAH metabolites were mainly naphthalene and fluorene. The detection concentrations of 2-OHFlu and 1-OHPhe in the final year were higher than those in the baseline (P<0.05). With the increase of exposure years, the abnormal rate of red blood cells in the final year was higher than that in the baseline (P<0.05). In addition, the abnormal rate of red blood cells increased with the increase of the concentrations of five metabolites of PAHs in urine, and the chi-square trend test was significant (P<0.05). The benchmark dose (BMD) of OH-PAHs was 0.67 μmol/mol Cr, 0.82 μmol/mol Cr, 1.40 μmol/mol Cr and 0.78 μmol/mol Cr, respectively. The BMD of 2-OHNap in people with barbecue diet habits was 0.23 μmol/mol Cr. The BMD of 2-OHNap in people without barbecue diet habits was 1.44 μmol/mol Cr. Conclusion There is a dose-response relationship between the concentration of PAHs metabolites in urine and the damage of red blood cells. Long-term exposure to PAHs can lead to hematological damage. It is suggested that targeted public health interventions should be formulated to reduce the exposure of the general population to PAHs.
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Objective:To summarize the prognosis of medullary thyroid carcinoma (MTC) patients with biochemical recurrence (the increase of postoperative calcitonin and no abnormal imaging) and to investigate the optimal cut-off value of calcitonin for postoperative structural recurrence (with imaging abnormality).Methods:Literature retrieval was conducted for PubMed, CNKI, EMbase, Web of Science, Cochrane and other databases, and literatures related to the increase of calcitonin after MTC surgery were included. Review Manager 5.4 software was used for Meta-analysis of the recurrence and death. SPSS 23.0 software was used and receiving operating characteristic (ROC) curve was used to analyze the rising folds of postoperative calcitonin level in comparison with the maximum value of experiment detection, and to predict the outcome of biochemical recurrence transforming to structural recurrence, and then the optimal cut-off value could be worked out.Results:A total of 7 studies including 1 005 MTC patients (276 cases of biochemical recurrence and 542 cases of biochemical cure). Meta-analysis showed that structural recurrence rate in postoperative biochemical recurrence group [40.6% (112/276) vs. 2.2% (12/542); OR = 27.99, 95% CI 14.57-53.78, P < 0.001] and mortality [10.0% (19/190) vs. 0.96% (3/312); OR = 7.26, 95% CI 2.42-21.84, P < 0.001] were higher than those in the biochemical cure group (normal postoperative calcitonin level and no disease state). The data of 89 MTC patients with biochemical recurrence were collected in another 4 studies. ROC curve analysis showed that area under the curve of the rising folds of postoperative calcitonin level in predicting structural recurrence was 0.825; according to the cut-off value at all sections, the optimal cut-off value of the increased postoperative calcitonin was 50 times, the sensitivity was 66. 7%, the specificity was 88.6%. Conclusions:MTC patients with postoperative biochemical recurrence have higher structural recurrence rate and mortality compared with patients with normal postoperative calcitonin. The postoperative elevation of calcitonin more than 50 times the maximum value of the laboratory detection can be taken as the critical diagnostic value, when more than 50 times is prone to structural recurrence.
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Objective:To investigate the efficacy and safety of the modified gasless unilateral axillary approach (MGUAA) endoscopic thyroid surgery in treatment of papillary thyroid microcarcinoma (PTMC) .Methods:From Jan. 2019 to Dec. 2019, 90 patients receiving PTMC (cT1N0M0, cI stage, 8th, 2017 AJCC) therapy by modified gasless unilateral axillary approach endoscopic thyroid surgery (MGUAA group, n=41) , and conventional open thyroid surgery (OS group, n=49) were retrospectively analyzed. Ninety patients were enrolled in the study, including 14 males and 76 females,with the mean age (42.1±12.0) years.The effectiveness of central lymph node dissection (CLND) , the operation time, the types of operation, the amount of drainage, the duration of hospital stay, the related complications, the postoperative pain of neck and axillary and the cosmetic satisfaction were compared between the two groups.SPSS 25.0 statistical software was used for statistical analysis, the measurement data was expressed by ±s, paired t test was used to compare the measurement data between groups, and Chi-square test was used to campare the count date between groups. Results:The mean age (35.0±8.6) years and the amount of surgical bleeding (12.3±7.3) ml in the MGUAA group were significantly lower than those (48.1±11.1) years and (16.1±4.3) ml in the OS group ( P<0.01) , while the mean operation time (99.1±19.5) min, the mean amount of drainage (221.4±67.9) ml and the postoperative drainage tube placement time (5.0±0.8) days were significantly higher than those of (70.6±17.8) min, (98.3±63.7) ml and (3.8±1.0) days in the MGUAA ( P<0.01) . There was no significant difference in the number of lymph nodes of CLND or the duration of hospital stay between the two groups ( P>0.05) . In terms of surgical complications, the transient recurrent laryngeal nerve injury, the postoperative hematoma, the postoperative infection, and the lymphatic leakage had no significant difference between the two groups ( P>0.05) . The MGUAA group had significant advantages in avoiding the postoperative dysphagia in front of neck, the postoperative pain of neck, and cosmetic satisfaction over the OS group [ (0.0% vs 28.6%) , (14.6% vs 71.4%) , (1.1±0.3) score vs (2.4±0.5) score ( P<0.01) ]. Whereas in axillary area pain on the surgical side, the MGUAA group was inferior to the OS group ( P<0.01) . Conclusion:The modified gasless unilateral axillary approach endoscopic thyroid surgery is a feasible, safe and cosmetically operation for PTMC (cT1N0M0, cI stage, 8th, 2017 AJCC) .
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Objective:To explore the impacts of workload and expected income index on the salary satisfaction of medical staff at public hospitals.Methods:From October 15th to November 10th, 2020, the salary system reform monitoring questionnaire for medical staff in public hospitals formulated by development center for medical science & technology National Health Commission was adopted to evaluate the workload, actual income, expected income and salary satisfaction of 120 pilot public hospitals for salary reforms in 21 cities (prefectures) in Sichuan province. The questionnaire survey was conducted among 8 651 medical staff of these hospitals. Descriptive analysis was carried out on the results of the questionnaire; the ratio of expected income to actual income, namely the expected income index, was used to reflect the relative difference between expected income and actual income; χ2 test and binary logistic regression were used to analyze the influencing factors of salary satisfaction. Results:8 133 valid questionnaires were recovered. The average working time per week of the survey subjects was 48.17 hours, and the average longest continuous working time was 15.30 hours; 85.63% (6 964) of the medical staff had expected income index greater than 1. The average score of salary satisfaction was 58.22 points and 57.72% (4 694) of the medical staff were dissatisfied. The longer the continuous working time (16-72 h versus 8-9 h, OR=0.755), the greater the expected income index (>1 versus =1, OR=0.522), and the lower the salary satisfaction. Conclusions:The workload of medical staff was heavy, the salary failed to meet the expected level, the sense of satisfaction was low. It is suggested to monitor in real time and dynamically adjust the workload of medical staff in combination with the actual situation, formulate the salary level in line with the technical labor value of different medical staff, and establish a comprehensive performance appraisal mechanism.
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BACKGROUND@#Previous studies have suggested that exposure to air pollution may increase stroke risk, but the results remain inconsistent. Evidence of more recent studies is highly warranted, especially gas air pollutants.@*METHODS@#We searched PubMed, Embase, and Web of Science to identify studies till February 2020 and conducted a meta-analysis on the association between air pollution (PM@*RESULTS@#A total of 68 studies conducted from more than 23 million participants were included in our meta-analysis. Meta-analyses showed significant associations of all six air pollutants and stroke hospital admission (e.g., PM@*CONCLUSIONS@#Exposure to air pollution was positively associated with an increased risk of stroke hospital admission (PM
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Humans , Air Pollutants/adverse effects , Air Pollution/adverse effects , Environmental Exposure/adverse effects , Hospitalization/statistics & numerical data , Incidence , Particle Size , Particulate Matter/adverse effects , Stroke/mortalityABSTRACT
BACKGROUND@#Decreased heart rate variability (HRV) is a predictor of autonomic system dysfunction, and is considered as a potential mechanism of increased risk of cardiovascular disease (CVD) induced by exposure to particulate matter less than 2.5 μm in diameter (PM@*METHODS@#An updated systematic review and meta-analysis of panel studies till November 1, 2019 was conducted to evaluate the acute effect of exposure to ambient PM@*RESULTS@#A total of 33 panel studies were included in our meta-analysis, with 16 studies conducted in North America, 12 studies in Asia, and 5 studies in Europe. The pooled results showed a 10 μg/m@*CONCLUSION@#Short-term exposure to PM
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Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Air Pollutants/analysis , Air Pollution/analysis , Heart Rate/drug effects , Particulate Matter/analysisABSTRACT
OBJECTIVE：To prepare and characterize glycyrrhetinic acid （GA）nanoparticles，and to evaluate its in vitro anti-tumor activity. METHODS ：Using PVP K 30 as carrier ，GA nanoparticles were prepared by anti-solvent precipitation and freeze-drying method. X-ray diffraction ，infrared spectrum ，differential scanning calorimetry and granularity analysis were used to characterize the nanoparticles ；HPLC method was used to measure the solubility and drug-loading amount of GA in the nanoparticles. MTT method was used to assay the in vitro inhibition activity of GA raw material and nanoparticles （GA doses were 12.5，25，50，100，200 μmol/L）on human liver cancer cell HepG 2 and calculate its IC 50. RESULTS ：The characteristic peaks of X-ray diffraction and infrared absorption of GA disappeared in the nanoparticles and the endothermic peak changed. The particle size of the nanoparticles was （194.88±23.52）nm，which was lower than （2 592.33±207.51）nm of raw material. The dispersion index was 0.24±0.04，which was higher than 0.15±0.03 of raw material. The average drug-loading amount of GA was 15.99％. Moreover，the solubility of nanoparticles increased from （1.05±0.01）μg/mL to（250.00±0.15）μg/mL. The results of antitumor test in vitro showed that the cell survival rates in the group of GA raw material 200 μmol/L and GA nanoparticles groups were significantly lower than that in blank control group ，and the cell survival rates of GA nanoparticles groups （except for 12.5 μmol/L group）were significantly lower than that of same dose group of raw material （P＜0.01）. IC 50 of GA nanoparticles was 86.3 μmol/L，which was lower than 364.4 μmol/L of raw material. CONCLUSIONS：GA nanoparticles are prepared successfully ；the prepared nanoparticles have small size and uniform distribution ，and the solubility are increased and antitumor activity in vitro are enhanced.
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Objective@#To investigate the mechanism of Al (mal) 3-induced ferroptosis in rat adrenal pheochromocytoma cells (PC12), to explore the effect of deferoxamine (DFO) .@*Methods@#Taken PC12 cells growing at logarithmic phase and divided into 6 groups: control group, 200 μmol/L Al (mal) 3 group, 0.5% DMSO group, 200 μmol/L DFO group, Al (mal) 3+DMSO group, Al (mal) 3+DFO group. DMSO and DFO were added to the DMSO group and the Al (mal) 3+DMSO group, the DFO group and the Al (mal) 3+DFO group for 2 h, respectively, Al (mal) 3 was then added to the Al (mal) 3 group, Al (mal) 3+DMSO group, and the Al (mal) 3+DFO group to a final concentration of 200 μmol/L. The cell viability was detected by CCK8, the morphology and ROS levels of PC12 cells was observed by inverted microscope, the cell proliferation toxicity and intracellular iron ion content were detected by colorimetry, the GSH content and GSH-PX activity were detected by biochemical method.@*Results@#Al (mal) 3 exposure significantly inhibited the growth of PC12 cells and destroyed the cell morphological structure, resulting in increased LDH activity and intracellular iron ion content in PC12 cells, decreased GSH content and GSH-PX activity, increased ROS levels; the combined treatment of Al (mal) 3+DFO can significantly improve the cell viability of PC12 cells, improved cell morphology, decreased cell LDH activity and intracellular iron ion content (P>0.05), increased GSH content and GSH-PX activity, decreased ROS levels.@*Conclusion@#Al (mal) 3 can induce ferroptosis in PC12 cells, DFO may inhibit ferroptosis by reducing intracellular iron levels and reducing oxidative damage.
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Objective To explore the nursing essentials of complicated incision infection and embedding syndrome after percutaneous endoscopy gastrojejunostomy(PEGJ). Methods Comprehensive treatment and care including improved nursing methods, negative pressure suction, the dressing strengthening, and enteral nutrition. Results The swelling of the incision gradually subsided. On the 18th day, there was slight redness around the tube, no exudate, no fever, and the incision healed well. On the 20th day, family members were taught with routine maintenance method of the PEG/J tube, and the patient was discharged from hospital with the tube home for continue treatment. Conclusion Comprehensive nursing methods according to cause analysis can improve the curative effect of complications after PEGJ implantation.
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To introduce the biological properties and functions of individual blood-brain barrier components,and summarize the most widely used in vitro blood-brain barrier models,compare their strengths and weaknesses,and provide suggestions on model selection in blood-brain barrier research and new-drug research and development.
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Objective:To investigate the effects of fluvastatin on high-sensitivity c-reactive protein( hs-CRP) , tumor necrosis fac-tor-α(TNF-α), urine albumer excretion rate (UAER)and serum creatinine (Cr) in the patients with early diabetic nephropathy. Methods:Totally 69 patients with early diabetic nephropathy were randomly divided into the observation group with 34 cases and the control group with 35 cases. The observation group was treated by low-protein diet plus fluvastatin, and the control group was treated by low-protein diet only. The course of treatment was 8 weeks. Totally 65 nondiabetic persons were selected as the normal group, and the levels of TNF-α, hs-CRP, UAER, ALT and Cr were detected before and after the treatment. Results:The levels of TNF-α, hs-CRP and UAER in the observation group and the control group were significantly higher than those in the normal group(P0. 05). Compared with that before the treatment, the level of UAER was de-creased significantly in the control group after the treatment (P0. 05). In the observation group, the levels of TNF-α, hs-CRP and UAER were all decreased sig-nificantly after the treatment (P<0. 05). Conclusion:UAER, hs-CRP and TNF-α are closely connected with diabetic nephropathy. Fluvastatin can decrease the levels of TNF-α, hs-CRP and UAER. Low-protein diet plus fluvastatin is effective and safe in the treat-ment of early diabetic nephropathy, and the efficacy is superior to that of low-protein diet only.
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Objective To introduce the competing risk model into outcome prediction of mild cognitive impairment (MCI) of seniors and to explore influencing factors for the prognosis of MCI to Alzheimer' s disease (AD).Methods Data were collected from six follow-up visits to 600 seniors from communities in Taiyuan city,which were conducted at an interval of six months from October 2010 to May 2013.MCI state was defined as the transient state,AD and death before AD as two absorbing states (death before AD in which was regarded as a competing risk event),building the competing risk model to identify the model parameters,and to explore influencing factors on MCI prognosis to AD.In the meantime,the 3-year MCI-AD transition probability was estimated based on the multi-state Markov model.Results Based on screening with the multivariate competing risk model analysis,factors such as higher age (estimate HR=1.56,95％CI:1.01-2.39),female gender (HR=1.72,95％CI:1.02-2.92),higher education(HR=0.64,95％CI:0.41-1.00),reading frequently (HR=0.57,95％CI:0.32-0.99),hypertension (HR=3.43,95％CI:1.08-10.85) and high SBP(HR=1.67,95％CI:1.04-2.66),were statistically significant for transition from MCI to AD in three years.3-year MCI-AD transition probability was 10.7％(95％CI:8.6％-13.2％).Conclusion Age,gender,education,reading and blood pressure were the influencing factors for the prognosis of MCI to AD.Competing risk model was advantageous in studying longitudinal data with multiple potential outcomes.
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BACKGROUND:Biological dressings with sealing negative pressure drainage can promote the healing of acute and chronic wounds. OBJECTIVE:To observe the clinical effects of biological dressings with sealing negative pressure drainage in repair of diabetic foot ulcer. METHODS: Totaly 40 patients with diabetic foot ulcer were enroled and al underwent debridement or debridement plus skin grafting treatment. Wound treatment methods were selected according to the wiling of patients. Patients in the test group (n=20) underwent polyvinyl alcohol hydration algae salt bubble wound dressings with sealing negative pressure drainage. Patients in the control group (n=20) underwent regular wound dressing treatment. At the 7th RESULTS AND CONCLUSION: The visual analog scale scores, blood sedimentation, C-reactive protein levels in the test group were lower than those in the control group (P < 0.05). The wound healing time in the test group was shorter than that in the control group (P < 0.05), and the patient satisfaction was higher in the test group than the control group (P < 0.05). There was no significant difference in economic costs between the two groups. There was no local or systemic toxicity, alergy and other adverse reactions in the test group. These results day of repair, visual analog scale scores, blood sedimentation, C-reactive protein levels, wound healing time, patient satisfaction and economic costs at the termination of the treatment in these two groups were compared. demonstrate that polyvinyl alcohol hydration algae salt bubble wound dressings with sealing negative pressure drainage in repair of diabetic foot ulcer is safe and effective to promote wound healing and reduce local inflammatory response.
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Professional postgraduates in geriatric medicine are one of the most important re-courses of geriatric specialists. However, training model for geriatric postgraduates is still unclear in China. In general, geriatric medicine has no independent training plan, and is included in internal medicine training. Such model cannot represent the feature of geriatric medicine. The present paper aimed to discuss the ability construction for geriatric postgraduates based on the geriatric medicine specialist training experience both at home and abroad, including diagnosis and treatment of multi-system diseases, ability of geriatric assessment, management of geriatric syndromes, consultation for geriatric rehabilitation and ability for continuity health service in order to cultivate the compound tal-ents suitable for the aging society requirement for geriatric medicine in China.
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Objective To understand the family burden of Alzheimer' s disease (AD) and associated factors.Methods The subjects were 168 caregivers of patients with AD selected from two class 3A hospitals and three communities in Taiyuan through cluster sampling.The data were collected by using the Caregiver Burden Inventory (CBI) and the Family Burden Scale (FBS) of diseases.Path analysis was applied to identify the factors associated with the total score of CBI.T-test and One-way analysis of variance were applied to identify the factors associated with the total score of FBS.Multiple linear regression analysis was applied to identify the factors associated with family burden of AD.Results The total score of the caregivers' burden was 52.41 ± 17.07.AD patients' cognitive function had direct (standardized β =-0.280,P＜0.001) and indirect effect on CBI;while daily performance of AD patients had indirect effect on CBI.The total score of family burden was 16.23 ± 9.00.Univariate analysis showed that the sex,age,education level,cognitive function,daily performance,mental status,depression and dementia rating of AD patients might affect the total score of FBS (P ＜ 0.05).Multivariate analysis showed that the factors which affected the total score of FBS included the sex (standardizedβ =0.280,P ＜ 0.01),cognitive function (standardizedβ =-0.158,P =0.033) and daily performance of AD patients (standardizedβ=-0.155,P=0.039).Conclusion The caregiver and family burden of AD was mainly associated with the cognitive function and daily performance of AD patients.It is necessary to take targeted measures to reduce the caregiver and family burden of AD.
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Objective To explore the Influence of different health education approaches to standard anticoagulation of non-valvular atrial fibrillation. Methods 400 patients with NVAF were randomly divided into the research group (n=200) and the control group (n=200). Baseline clinical information was recorded. Both groups were given regular education and treatment. The control group was randomly divided into two subgroups. One subgroup (patients or/and family members) was given knowledge lectures of atrial fibrillation, atrial fibrillation anticoagulant, and application of warfarin. The other was given the knowledge through booklets. Standard anticoagulation fulfillment rate, ischemic stroke, other events of artery embolism, major bleeding, minor bleeding and death in the two groups were observed after 1 year. The cost for different education approaches was also compared between the 2 subgroups. Results (1)In the research group, standard anticoagulation fullfillment rate (40.53%) was higher than that of the control group(15.96%) (P0.05).Other artery embolism rate , major bleeding, minor bleeding, death rate had no statistical difference. (2)Knowledge lecture group (10.8±1.0 min) spend more time than the booklet group (1.0±0.5 min) (P<0.01). The booklet group (5.1±1.1 yuan) costed more in terms of money than the knowledge lecture group (1.8±0.5 yuan) (P<0.01). (3)The knowledge lecture group showed higher standard anticoagulation fulfillment rate (47.96%) than that of booklet group (32.60%) (χ2=7.33, P<0.01). There was no statistical difference in ischemic stroke rate, other artery embolism rate, major bleeding rate, minor bleeding rate and the death rate. Conclusions Detailed, correct anticoagulant education and guidance can improve NVAF patients with standard anticoagulation, and reduce the risk of ischemic stroke. Knowledge lecture consumes more time but can improve the standard anticoagulation fulfillment rate.
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The clinical features and endoscopic findings of 50 with esophageal ulcers were retrospectively reviewed.The ratio of male to female was 3.5∶1 (39∶11, P0.05 ).However deep , large (≥2.5 cm ) and irregular esophageal ulcers were more likely to be malignant ( P <0.01 ).The clinical and endoscopic findings reveal that the malignancy of esophageal ulcer is correlated with the size , depth and shape of the lesions.
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Objective To study on the effect of situational teaching based on ECS in medical nursing teaching.Methods 93 nursing students were divided into the experimental group (45 cases) and the control group (48 cases).The experimental group adopted ECS in the medical nursing situational teaching,while the control group used conventional teaching method.The teaching results between the two groups were compared between two groups.Results Two groups had significant differences in the medical nursing theory test and the operation skills examination.The students in the experimental group had higher recognition on the situational teaching based on ECS,especially in the learning initiative and interest,pathology observation ability and the unity cooperation ability,the differences showed statistical difference.Conclusions The application of ECS in the medical nursing situational teaching can stimulate the learning interest of the nursing students,help the cultivation of clinical thinking ability,relieve the contradiction of resources strain in nurses clinical probation and promoting the improvement of medical nursing teaching.
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OBJECTIVE@#To investigate the mechanism of activator protein-1 (AP-1) on cigarette smoke-induced airway mucous hypersecretion and to explore the possible signal transduction pathway that activates AP-1.@*METHODS@#The airway epithelial cell line (BEAS-2B) was cultured in vivo and treated with cigarette smoke extract (CSE). The DNA binding activity of AP-1 was blocked by the transfection of c-Jun dominant negative mutant TAM67 into the cells. SP600125 and PD98059 were used to block the activation of c-Jun terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) respectively. MUC5AC protein was detected by enzyme-linked immunosorbent assay, MUC5AC mRNA level was analyzed by RT-PCR, while the protein contents of p-JNK, p-ERK and p-P38 were detected by Western blot, and the DNA binding activity of AP-1 was determined by electrophoretic mobility shift assay.@*RESULTS@#The MUC5AC protein production and mRNA expression in the CSE group were significantly higher than those in the control group, and the DNA binding activity of AP-1 was also higher than that in the control group (P0.05). After the transfection of TAM67 into the cells, the expression levels of MUC5AC protein and mRNA and the binding activity of AP-1 decreased significantly (P<0.01). The DNA binding activity of AP-1 and the expression levels of MUC5AC protein and mRNA were lower in the SP600125 group and in the PD98059 group than those in the CSE group (P<0.05).@*CONCLUSION@#After being activated by JNK and ERK which are phosphorylated by cigarette smoke, AP-1 binds to its DNA binding elements on the promoter of MUC5AC gene and up-regulates the MUC5AC expression at the transcriptional level.
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Humans , Bronchi , Cell Biology , Cells, Cultured , Epithelial Cells , Cell Biology , Metabolism , Mucin 5AC , Genetics , Metabolism , Smoke , Smoking , Tobacco , Chemistry , Transcription Factor AP-1 , PharmacologyABSTRACT
Objective To investigate the effects of hyaluronan (HA) and CD44 on airway mucous hypersecretion,and explore the molecular mechanism of activation of epidermal growth factor(EGF)/epidermal growth factor receptor(EGFR) signal transduction pathway by signal factors. Methods BEAS-2 B airway epithelial cells were cultured in vitro,and were stimulated by neutrophil elastase(NE).Reactive oxygen species(ROS)scavenger(DMTU),hyaluronidase(Hase),CD44 antibody and tissue kallikrein(TK)inhibitor(PI)were served as interventional factors,and control group(serum free culture),NE stimulation group(50 nmol/L NE),DMTU+NE group(20μmol/L DMTU+50 nmol/L NE),DMTU+Hase+NE group(20 μmol/L DMTU+10μg/mL Hase+50 nmol/L NE),CD44Ab+NE group(5 μg/mL CD44Ab+50 nmol/LNE)and PI+NE group(1 00μg/mL PI+50 nmol/L NE)were established.The expression of mucin(MUC)5AC mRNA was detected by RT-PCR,the expression of MUC5AC and EGF protein was determined by ELISA,and the expression of phosphorylated epidermal growth factor receptor(p-EGFR)protein was analysed by Western blotting. Results The expression of MUC5AC,EGF and p-EGFR protein and MUC5AC mRNA in NE stimulation group was significantly higher than that in control group(P<0.01),the expression in DMTU+NE group was significantly lower than that in NE stimulation group(P<0.01),the expression in MTU+Hase+NE group was significantly higher than that in DMTU+NE group(P<0.05 for MUC5AC and p-EGFR protein and MUC5AC mRNA,and P<0.01 for EGF protein),the expression in CD44Ab+NE group and PI+NE group was significantly higher than that in NE stimulation group(P<0.05 for MUC5AC and p-EGFR protein and MUC5AC mRNA,and P<0.01 for EGF protein). Conclusion NE up-regulates the expression of MUC5AC gene via ROS/HA/CD44/TK/EGF/EGFR signal transduction pathway in airway epithelial cells.