Objective To establish a liquid chromatography method for the simultaneous determination of 13 aromatic amine compounds (AAs) in workplace air. Methods A total of 13 AAs in both vapor and aerosol phases were collected in workplace air using a new GDH-6 sampling tube. Samples were desorbed and eluted with methanol, separated using a Symmetry Shield™ RP₁₈ reversed-phase liquid chromatography column, and detected with a diode array detector. Quantification was performed using an external standard method. Results The linear range of the 13 AAs measured by this method was 0.02-373.60 μg/L with the correlation coefficients greater than 0.999 0. The minimum detection concentration was 0.09-14.37 μg/m³, and the minimum quantitative concentration was 0.31-47.90 μg/m³ (both calculated based on sampling 15.0 L of air and 3.0 mL of elution volume). The average desorption and elution efficiency ranged from 97.46% to 101.23%. The within-run relative standard deviation (RSD) was 0.10%-5.99%, and the between-run RSD was 0.17%-2.71%. Samples could be stably stored in sealed conditions at 2-8 ℃ for more than seven days. Conclusion This method is suitable for the simultaneous determination of 13 AAs in workplace air, including both vapor and aerosol phases.

Objective To establish a method for simultaneous determination of four high-molecular-weight thiol derivatives (TDs) in workplace air by gas chromatography. Methods The four kinds of vapor-phase macromolecular TDs (1-pentanethiol, 1-hexanethiol, 1-benzyl mercaptan, and n-octanethiol) in the workplace air were collected using the GDH-1 air sampling tubes, desorbed with anhydrous ethanol, separated on a DB-FFAP capillary column, and determined by flame ionization detector. Results The quantitation range of the four TDs was 0.30-207.37 mg/L, with the correlation coefficients greater than 0.999 00. The minimum detection mass concentrations and minimum quantitation mass concentrations were 0.18-0.32 and 0.60-1.05 mg/m³, respectively (both calculated based on the 1.5 L sample and 3.0 mL desorption solvent). The mean desorption efficiencies ranged from 87.07% to 103.59%. The within-run and between-run relative standard deviations were 1.92%-8.22% and 1.89%-8.45%, respectively. The samples can be stored at room temperature or 4 ℃ for three days and up to 7 days at -18 ℃. Conclusion This method is suitable for the simultaneous determination of four vapor-phase TDs in workplace air.

Objective To analyze the characteristics and causes of an occupational acute carbon monoxide poisoning incident caused by a nitrogen generator malfunction. Methods The workers and the workshop from an electronic component manufacturing company in Guangzhou City, which had an occupational acute carbon monoxide poisoning incident, were selected as the research subjects using the retrospective investigation method. Relevant data of worksite survey of occupational health, clinical records of poisoning patients, and occupational disease diagnosis data were collected for analysis. Results A total of 15 workers who experienced discomfort in this incident, were from the final inspection workshop using high-purity nitrogen (purity of 99.999%). The short-term exposure concentration of carbon monoxide in the workplace air at three oven operating posts using high-purity nitrogen was 64.1, 581.0, and 142.0 mg/m³, respectively, while the concentration in the workplace air at the oven operating posts using regular nitrogen and the nitrogen-generating room was <0.1 mg/m³. Carboxyhemoglobin saturation levels in the 15 patients ranged from 2.000%-17.300%. Occupational acute mild carbon monoxide poisoning was diagnosed in nine patients, occupational acute carbon monoxide exposure reactions was diagnosed in six patients. This poisoning incident was caused by machine malfunction and improper operation, leading to occupational acute carbon monoxide poisoning. Conclusion Companies using nitrogen production machine should enhance their ability to identify carbon monoxide risks, strengthen training and management of workers, establish emergency response plans for nitrogen production and use, ensure proper maintenance of production equipment, and optimize operational procedures to prevent acute poisoning incidents.

[摘 要] 目的：探究长链非编码RNA葡萄糖醛酸酶β假基因11（GUSBP11）调节miR-339-5p/小鼠双分钟同源物2（MDM2）轴对胃癌细胞AGS增殖、迁移和侵袭的影响。方法：收集2023年12月至2024年6月期间在广州中医药大学附属佛山中医院手术治疗的25例胃癌患者的癌旁组织及癌组织。常规培养胃癌细胞AGS和正常胃黏膜上皮细胞GES-1，用转染试剂将对照质粒和敲减质粒转染AGS细胞，分为Ctrl组、sh-NC、sh-GUSBP11、sh-GUSBP11 + anti-NC、sh-GUSBP11 + anti-miR-339-5p。qPCR法检测胃癌组织及各组细胞中GUSBP11、miR-339-5p和MDM2 mRNA的表达；双萤光素酶报告基因实验检测GUSBP11或MDM2与miR-339-5p间的靶向关系；EdU法检、Transwell小室实验、划痕愈合实验和WB法分别检测各组AGS的增殖、迁移和侵袭能力和细胞中CDK1、MMP-2、MMP-9蛋白的表达；AGS细胞移植瘤实验检测敲减GUSBP11对移植瘤生长的影响。结果：胃癌组织和细胞中GUSBP11、MDM2 mRNA均呈高表达（均P < 0.05），miR-339-5p呈低表达（P < 0.05）。GUSBP11与miR-339-5p和MDM2与miR-339-5p间存在靶向关系。在AGS细胞中敲减GUSBP11可明显抑制MDM2蛋白、促进miR-339-5p的表达而抑制miR-339-5p则可促进MDM2蛋白表达。敲减GUSBP11可抑制AGS细胞的增殖、迁移和侵袭能力而抑制miR-339-5p则可逆转此作用。敲减GUSBP11可明显抑制CDK1、MMP-2和MMP-9蛋白的表达而抑制miR-339-5p则可逆转此作用。敲减GUSBP11可明显抑制AGS细胞移植瘤的生长。结论：GUSBP11在胃癌组织和细胞中呈高表达，敲减GUSBP11表达可能通过调控miR-339-5p/MDM2轴抑制胃癌细胞的恶性生物学行为。

Objective To improve the national standardized method for determining biphenyl in workplace air, which was based on activated carbon tube sampling, carbon disulfide desorption, and gas chromatography, by developing a method using GDX-502 tubes for sampling, toluene for desorption, and gas chromatography. Methods Workplace air samples were collected using GDX-502 sampling tubes and desorbed with toluene, followed by determination with gas chromatography. Results The improved method demonstrated good linearity for biphenyl concentrations ranging from 0.33 to 330.00 mg/L, with a correlation coefficient of 0.999 9. The detection limit and lower limit of quantification were 0.06 and 0.21 mg/L, and the minimum detection concentration and minimum quantification concentration were 0.04 and 0.14 mg/m³ (based on 1.5 L air sample volume), respectively. The average desorption efficiency ranged from 96.6% to 101.1%. The within-run and between-run relative standard deviations were 0.6%-1.4% and 1.4%-3.3%, respectively, with 100.0% sampling efficiency. Samples remained stable for at least 14 days at room temperature. Conclusion The improved method for biphenyl detection demonstrates rapid and accurate performance, with the advantages of low detection limits and high sampling and desorption efficiency.

Objective To compare the long-term prognosis differences between surgical radical resection and endoscopic resection for early gastric cancer patients based on the SEER database. Methods A total of 1 437 patients with stage Tis to T_1b gastric adenocarcinoma were selected from the SEER database from January 1, 2004 to December 31, 2013. They were divided into a surgery group (n=1 257) and an endoscope group (n=180) according to the treatment method. Kaplan-Meier survival curve and Cox regression model were used to analyze survival outcomes. Results The patients in the surgery group were younger than those in the endoscope group ([67.63±12.97] years old vs [71.29±10.82] years old), with higher rates of T₁ stage (97.45% vs 87.78%) and lymph node metastasis (19.73% vs 5.00%, all P＜0.001). The median follow-up time for all patients was 37 (15, 66) months, and the mortality rate of gastric cancer in the endoscope group was lower than that in the surgery group (23.33% vs 27.13%, P＜0.001). Univariate Cox analysis showed that treatment modality, age, sex, T stage, lymph node metastasis were all associated with early gastric cancer mortality (all P＜0.05), and the risk of death in the endoscope group was 43% of that in the surgery group (HR=0.43, P=0.015). After adjusting for multiple factors, there was no statistically significant difference in mortality risk between the two groups (P=0.067), but after excluding lymph node positive patients, the mortality risk in the endoscope group was 46% of that in the surgery group (HR=0.46, P=0.048). Conclusions For early gastric cancer patients with negative lymph nodes, endoscopic resection may provide better survival benefits than surgical procedures, suggesting that it can be the preferred treatment strategy for patients with low risk of lymph node metastasis.

Objective To evaluate the diagnostic value of myocardial work related parameters in coronary ischemia patients with coronary artery disease(CAD)coronary ischemia using non-invasive left ventricular pressure strain loop(PSL),taking fraction flow reservation(FFR)as the gold standard.Methods From December 2020 to December 2021,53 clinically suspected CAD patients were prospectively enrolled.All patients underwent echocardiography,invasive coronary angiography and FFR measurement.According to the results of coronary angiography,patients were divided into myocardial ischemia group(n=24,FFR≤0.80)and non-myocardial ischemia group(n=29,FFR＞0.80).PSL was used for off-line analysis to obtain the global work index(GWI),global constructive work(GCW),global wasted work(GWW),global work efficiency(GWE),global positive work(GPW),and global systolic constructive work(GSCW)and other myocardial work parameters.The differences of parameter values between the two groups were compared.The diagnostic efficacy of work parameters in myocardial ischemia was analyzed by ROC curve.Results Compared with the non-myocardial ischemia group,GWI,GCW,GPW and GSCW were significantly decreased in the myocardial ischemia group at the 18-,16-,and 12-segment levels(P＜0.001).The ROC curve showed that the AUC results of GWI,GCW,GPW,GSCW at the 18-segment level were 0.803(95％CI 0.679-0.927),0.807(95％CI 0.687-0.928),0.822(95％CI 0.708-0.936),0.819(95％CI 0.703-0.935).The optimal cut-off value of GWI was 1 676.3 mmHg％,and the sensitivity,specificity and accuracy of predicting myocardial ischemia were 70.8％,86.2％and 79.2％,respectively.The optimal cut-off value of GCW was 1 999.4 mmHg％,and the sensitivity,specificity and accuracy of predicting myocardial ischemia were 75.0％,82.8％and 79.2％,respectively.Conclusions Analyzing myocardial work using PSL has good significance for screening suspected myocardial ischemia in CAD patients.

Biotoxins, which include bacterial, fungal, marine, plant, and animal toxins, are widespread in living and occupational environments, posing potential threats to human health. Rapid detection of biotoxins in blood is crucial for preventing health hazards and enabling timely disease diagnosis and treatment. Biosensors and immunoassay technologies have critical advantages in the rapid detection of biotoxins in blood. Common biosensors, such as surface plasmon resonance biosensors and fluorescent biosensors, enhance sensitivity and reduce detection limits through signal amplification. Common immunoassay methods, such as colloidal gold immunochromatography, fluorescence immunochromatography, and chemiluminescence immunoassay, improve detection efficacy and sensitivity through specific antibody-antigen binding and nanotechnology. However, current rapid detection technologies of bitoxins in blood face challenges such as matrix interference and insufficient specificity, and they fall short in high-throughput detection of multiple toxins simultaneously. Future developments should focus on improving sample pretreatment, innovating signal amplification methods, enhancing specificity on recognition of elements, and designing portable detection devices and high-throughput platforms for simultaneous toxin analysis. These advancements aim to improve the sensitivity and reliability of detection methods, providing more accurate and convenient solutions for biotoxin detection in blood.

ObjectiveTo understand the monitoring result of occupational hazard in the workplace of key industries in Guangdong Province from 2020 to 2023. Methods The data of occupational hazards in the workplace of 20 key industries in Guangdong Province from 2020 to 2023 were collected from the “Workplace Occupational Hazard Monitoring System” of the Chinese Disease Prevention and Control System subsystem. The monitoring result of occupational hazard factors, occupational health training, occupational health examination, occupational protection, detection of occupational hazardous agents such as dust, chemical substances and noise were analyzed. Results A total of 13 058 enterprises from key industries were recruited as the monitoring subjects in Guangdong Province. There were 290 large-, 1 342 medium-, 7 635 small-, and 3 791 micro-enterprises, with small and micro-enterprises accounting for 58.5% and 29.0% of the total, respectively. A total of 7 542 enterprises exceeded the national standard in the detection of occupational hazards, with a rate of 57.8%. A total of 1 942 517 workers from 13 058 enterprises were recruited, with 835 567 workers were exposed to occupational hazards, with a rate of 43.0%. The rate of occupational health training for enterprise leaders, occupational health management personnel, and workers was 71.9%, 73.8%, and 86.5%, respectively. The abnormal rate of occupational health examinations for workers exposed to noise, dust, and chemical agents was 2.0%, 0.6%, and 1.0%, respectively. The distribution rate of dust masks, anti-poisoning masks or face masks, and noise prevention earplugs or earmuffs was 83.3%, 71.3%, and 77.8%, respectively. The rate of installation of dust prevention facilities, anti-poisoning facilities, and noise prevention facilities was 85.6%, 81.2%, and 50.1%, respectively. The rate of exceeded the national standard of dust, noise in the worksites/types and workplaces showed a decreasing trend year by year (all P<0.01), while the rate of exceeded the national standard of chemical agents in worksites/types and workplaces showed an increasing trend year by year in various occupational hazards (all P<0.01). Conclusion Occupational hazards in the workplace of key industries in Guangdong Province are relatively common. The proportion of workers exposed to occupational hazards is relatively high. It is necessary to further improve the use of noise prevention facilities and protective equipment, strengthen occupational health training for enterprises throughout the province and regularly monitor occupational hazards to reduce the risk of occupational diseases.

ObjectiveTo establish a method for the determination of 1,1,1,2-tetrachloroethane (TeCA) and 1,1,2,2-TeCA in human urine using liquid-liquid extraction-gas chromatography. Methods The 5.0 mL urine sample was mixed with 2.0 g anhydrous sodium sulfate and 5.0 mL ethyl acetate, then vortexed mixing. The 1.0 mL extraction was separated by 100% dimethylpolysiloxane capillary gas chromatography column, detected by flame ionization detector, and quantified by an external standard method. Results The linear ranges of 1,1,1,2-TeCA and 1,1,2,2-TeCA were 0.250-50.750 mg/L, with both correlation coefficients of >0.999 9. The detection limit of 1,1,1,2-TeCA in urine was 0.020 mg/L, and the lower limit of quantification was 0.060 mg/L. The average recovery was 88.02%-101.32%, and the within-run and between-run relative standard deviations (RSDs) were 0.11%-0.47% and 0.39%-1.09%, respectively. The detection limit of 1,1,2,2-TeCA in urine was 0.050 mg/L, and the lower limit of quantification was 0.150 mg/L. The average recovery was 93.42%-101.32%, and the within-run and between-run RSDs were 0.28%-1.04% and 0.50%-1.03%, respectively. Both the 1,1,1,2-TeCA and 1,1,2,2-TeCA cannot be stored at room temperature. The 1,1,2,2-TeCA can be stored at 4 ℃ for at least three days. At -20 ℃, the 1,1,1,2-TeCA can only be stored for one day, while 1,1,2,2-TeCA can be stored for at least five days. Conclusion This method has high sensitivity, good specificity, simple sample pretreatment, and more intuitive and reliable results. It can be used to determine the level of 1,1,1,2-TeCA and 1,1,2,2-TeCA in urine of occupational population.