Objective:To investigate the molecular mechanism by which 2',4'-dihydroxychalcone(D2)inhibits proliferation,migration,and epithelial-mesenchymal transition(EMT)in colorectal cancer cells through miR-7-5p-mediated autophagy.Methods:Human colorectal cancer cell lines HCT-15 and SW620 were treated with D2 at concentrations of 0,12.5,25,and 50 μmol/L.Cell proliferation and clonogenic capacity were evaluated using MTT and colony formation assays.Cell migration was assessed by wound healing and Transwell assays.WB assay was used to detect the expression of EMT-related proteins,autophagy-related proteins,and key components of the PI3K/AKT/mTOR pathway.Autophagosome formation was visualized by immunofluorescence staining.TCGA database and KEGG pathway analyses were performed to evaluate miR-7-5p expression and its association with colorectal cancer.RT-qPCR was used to quantify miR-7-5p expression,and lentiviral transduction was employed to establish stable miR-7-5p knockdown or overexpression cell lines.Results:D2 significantly inhibited colorectal cancer cell proliferation,migration,and EMT(P<0.05 or P<0.01).TCGA and KEGG analyses revealed that miR-7-5p expression was downregulated in colorectal cancer and closely associated with disease progression.D2 treatment(12.5,25,and 50 μmol/L)significantly upregulated miR-7-5p expression in HCT-15 and SW620 cells(P<0.01).At 25 μmol/L,D2 increased the expression of autophagy-related proteins(LC3 and p-ULK1)and inhibited the PI3K/AKT/mTOR signaling pathway(P<0.05),accompanied by increased autophagosome formation(P<0.01).In miR-7-5p-knockdown cells treated with D2,the levels of LC3 and p-ULK1 were significantly reduced compared to D2-only treated cells(P<0.05 or P<0.01).Conclusion:D2 upregulates miR-7-5p to induce autophagy,thereby inhibiting colorectal cancer cell proliferation,migration,and EMT,possibly through suppression of the PI3K/AKT/mTOR signaling pathway.

Background A number of studies have shown that heavy metals in atmospheric PM_2.5 have impacts on human health, while studies on the impact of long-term and low-concentration exposure to lead in PM_2.5 on human health are limited. Objective To investigate the pollution characteristics of lead in ambient PM_2.5 and assess its chronic health risks. Methods Daily PM_2.5 concentration data in Jinan from 2014 to 2019 were collected, and the year-by-year trend of PM_2.5 concentration was analyzed. Licheng District (an industrial area) and Shizhong District (a residential area) were elected to install an ambient PM_2.5 monitoring stationrespectively. The sampling instrument was a 100 L·min⁻¹ high-flow PM_2.5 sampler, with a cumulative sampling time of 20-24 h per day, using a quartz fiber filter membrane for lead detection and a glass fiber filter membrane for PM_2.5 determination. The sampling frequency was 7 consecutive days per month from the 10^th to the 16^th (A total of 493 d were sampled and some were missing; 172 d during the heating period and 321 d during the non-heating period). Two PM_2.5 samples were collected in one monitoring site each day. A total of 986 samples were collected in one monitoring site. The lead content in PM_2.5 samples was detected by inductively coupled plasma mass spectrometry. The concentration of PM_2.5 was measured by weighing method. The annual average concentration and enrichment factor of lead in PM_2.5, the change trend of lead content per unit mass of PM_2.5, and the difference between heating period and non-heating period from 2014 to 2019 were estimated. Technical guide for environment health risk assessment of chemical exposure (WS/T 777-2021) was used to assess the health risks of exposure to lead in PM_2.5. Results The average annual concentration of lead in PM_2.5 ranged from 23.2 ng·m⁻³ to 154.7 ng·m⁻³. The average concentration in heating period from 2015 to 2019 was higher than that in non-heating period, and the differences in 2015, 2017, and 2019 were statistically significant (P < 0.01 or 0.001). The enrichment factors ranged from 200 to 1342 in 2014 to 2019. The average enrichment factors in heating period in 2015, 2017, and 2018 was higher than those in non-heating period, and the difference was statistically significant (P < 0.05 or 0.001). The lead contents per unit mass of PM_2.5 ranged from 493 ng·mg⁻¹ to 1944 ng·mg⁻¹, and the differences between heating period and non-heating period in 2014, 2017, and 2018 were statistically significant (P < 0.05 or 0.001). The average annual concentration and enrichment factor of lead in PM_2.5 showed a downward trend, and thus the lead content per unit mass of PM_2.5 also decreased. From 2014 to 2019, the carcinogenic risk of lead in PM_2.5 in Jinan ranged from 1.69×10⁻⁸ to 2.45×10⁻⁶, showing a significant downward trend year by year, and the 95^th percentile decreased by 3%-46% from the previous year. The carcinogenic risk level of lead was reduced to an acceptable level (<1×10⁻⁶) after 2017. Conclusion From 2015 to 2019, lead concentration and enrichment factor in PM_2.5 increase during heating period compared with non-heating period, but it is not completely consistent of lead content in PM_2.5 per unit mass. From 2014 to 2016, exposure to lead in PM_2.5 may elevate carcinogenic risk to human. After 2017, the carcinogenic risks of exposure to lead in PM_2.5 are at an acceptable level.

Objective:To explore the clinical effect of positive reinforcement theory nursing intervention in the rehabilitation treatment of patients with cervical spondylosis and its influence on cervical function and quality of life.Methods:From March 2017 to May 2020, 94 patients who received rehabilitation after anterior cervical decompression surgery were selected as the research samples. They were divided into the control group and the study group by random digits table method with 47 cases in each group. The control group was given routine nursing care, and the study group received positive reinforcement theoretical nursing intervention on the basis of the control group.The nursing effect,cervical vertebra function and quality of life before and after nursing were evaluated by Visual Analogue Scale(VAS), Japanese Orthopaedic Association assesses treatment(JOA) score, SF-36. The nursing satisfaction rate was evaluated by questionnaire.Results:The JOA score, quality of life score and VAS score of the study group before nursing were (7.57 ± 1.35), (56.78 ± 5.62), (6.53 ± 0.34) respectively, while those of the control group were (7.32 ± 1.27), (56.32 ± 5.31), (6.32 ± 0.31) respectively, and there was no significant difference between the two groups ( P > 0.05). The JOA score and quality of life score of the study group after nursing were (15.73 ± 0.33) and (91.67 ± 2.34) respectively, which were higher than those of the control group (12.18 ± 0.46) and (83.43 ± 3.33) respectively. The VAS score of the study group after nursing was (2.33 ± 0.11) and lower than that of the control group (4.53 ± 0.25). The differences were statistically significant ( t values were 3.47, 5.43, 4.67, P< 0.05). Compared with the control group, the nursing satisfaction rate of the study group was higher than that of the control group (85.11%, 40/47 vs. 97.87%,46/47, χ2 value was 4.92, P < 0.05). Conclusions:Positive reinforcement theory nursing intervention can effectively relieve the pain symptoms of patients, improve the cervical function, and effectively improve the quality of life.

Objective:To study the effect of comprehensive nursing combined with cervical spine health care on postoperative psychological status and the prevention of various complications of patients with cervical spine surgery.Methods:A total of 102 patients who underwent cervical spine surgery in Dalian Third People′s Hospital from June 2018 to February 2020 were selected as the research objects. The patients were randomly divided into a control group and an experimental group. The control group was given routine care, and the experimental group was given comprehensive care combined with cervical spine for health care intervention, the main observation indicators included the mental state of the two groups of patients, the incidence of postoperative complications, and the patients' satisfaction with nursing work.Results:After comprehensive nursing combined with cervical health care intervention, the SAS score of the control group was 50.14±3.51 and the SAS score of the experimental group was 30.27±1.12. The SAS score of the control group was significantly higher than that of the experimentalgroup ( t value was 24.134, P< 0.05); the SDS score of the control group was 50.45±1.11, the SDS score of the experimental group was 39.45±2.21, the SDS score of the control group was significantly higher than that of the experimental group ( t value was 20.293, P<0.05), the difference was statistical significance: Compared with the control group (27.45%,14/51), the incidence of postoperative complications (9.80%,5/51) in the experimental group was significantly reduced ( χ2 value was 10.409, P<0.05); the nursing attitude of the patients to nursing staff (91.11± 5.32), nursing quality (90.41±2.30), nursing responsibility (92.82±4.69) in the experimental group were all significantly higher than those of the control group (80.67±3.51, 80.21±4.43, 80.78±4.82), the difference was statistically significant ( t value was 9.151, 14.671, 16.124, P<0.05). Conclusion:Rehabilitation nursing intervention of comprehensive nursing combined with cervical spine health care can improve mental state, reduce incidence of complication and increase satisfaction degree for patients undergoing cervical spondylopathy surgery, which is worthy of further clinical application and promotion.

OBJECTIVE: To study the biological exposure limit of 1,3-butadiene occupational exposure. METHODS: A total of 139 workers who exposed to 1,3-butadiene in a rubber plant was chosen as exposure group,and 45 workers without 1,3-butadiene exposure were chosen as control group by judgment sampling method. Gas chromatography-flame ionization detection method was used to detect the level of 1,3-butadiene in workplace air,and ultra-high performance liquid chromatography-tandem mass spectrometric was used to determine the level of urinary dihydroxybutyl mercapturic acid( DHBMA) in end-of-shift workers. The correlation between 1,3-butadiene level and urinary DHBMA level was analyzed.The biological limit of 1,3-butadiene occupational exposure was assessed. RESULTS: The range of concentration-time weighted average( C_(TWA)) of 1,3-butadiene was from 0. 004 to 7. 609 mg/m~3,the medium was 0. 253 mg/m~3 in the exposure group,while the level of urinary DHBMA was from 0. 171 to 4. 235 mg/g Cr,and the medium was 1. 220 mg/g Cr. The range of C_(TWA)of 1,3-butadiene was below detection limit in the control group. The level of urinary DHBMA was from 0. 157 to 1. 808 mg/g Cr,and the medium was 0. 627 mg/g Cr in the control group. The level of urinary DHBMA in the exposure group was higher than that of the control group( P < 0. 01). The level of urinary DHBMA( y) of workers was related to the level of 1,3-butadiene( x) of the workplace air in the exposure group( y = 0. 349 x + 1. 082,P < 0. 01).CONCLUSION: DHBMA in urine could be used as a biomarker for 1,3-butadiene exposure in workers. The recommended biological exposure limit of DHBMA is 2. 900 mg/g Cr.