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 explore the effect of volatile oil of Ligusticum chuanxiong on the transdermal properties and cytotoxicity of triptolide in vitro. METHODS The chemical constituents of the volatile oil of L. chuanxiong were analyzed by gas chromatography-mass spectrometry. The lower abdominal skin of KM mice was separated and divided into triptolide group， triptolide in compatibility with volatile oil of L. chuanxiong groups at 1∶10， 1∶50， 1∶100 （hereinafter referred to as “compatibility 1∶10”“compatibility 1∶50”“compatibility 1∶100” groups）. After the skin of mice in each group was fully exposed to 0.2 g of the corresponding cream for 24 h， the cumulative transdermal dose （Qn） of triptolide in the receiving solution of each group was determined by high-performance liquid chromatography， and the transdermal absorption rate （Jss） was calculated. Human immortalized keratinocytes （HaCat） were used as a model， the CCK-8 method was used to detect the cell survival rate of different concentrations of the volatile oil of L. chuanxiong and triptolide before and after compatibility. RESULTS A total of 62 chemical constituents of the volatile oil of L. chuanxiong were identified， including Z-ligustilide， senkyunolide， and β-selinene. The Qn （P＜ 0.01） and Jss of triptolide increased within 24 h in the compatibility 1∶10 and 1∶50 groups， while the Qn （P＜0.05） and Jss decreased in the compatibility 1∶100 group as compared with the triptolide group. Compared with the triptolide group， the cell survival rate of HaCat was significantly increased in the compatibility 1∶10 and 1∶50 groups when the triptolide concentrations were 36， 72 and 144 ng/mL （P＜0.05 or P＜0.01）； while the cell survival rate of HaCat was decreased in the compatibility 1∶100 group， but the difference was not statistically significant （P＞0.05）. CONCLUSIONS When the compatibility ratio of triptolide and volatile oil of L. chuanxiong was 1∶10 or 1∶50， it can promote the transdermal absorption of triptolide and reduce the cytotoxicity of triptolide to HaCat.

Objective To analyze the diagnostic efficacy and clinical significance of magnifying endoscopy combined with narrow-band imaging(ME-NBI),acetate-indigo rouge staining and multi-slice spiral CT for early gastric cancer and precancerous lesions.Methods 202 patients with suspected early gastric cancer and precancerous lesions from February 2019 to March 2022 were regarded as the subjects of this study,all the patients underwent ME-NBI,acetate-indigo rouge staining,and multi-slice spiral CT examination;The diagnostic value of different examination methods for early gastric cancer and precancerous lesions was analyzed using the receiver operator characteristic curve(ROC curve),using the pathological results of gastric cancer as the gold standard,the diagnostic value of ME-NBI,acetate-indigo rouge staining combined with multi-slice spiral CT and their combination in early gastric cancer and precancerous lesions was analyzed using a four grid table.Results The image quality of ME-NBI and acetate-indigo rouge staining combined examinations was significantly higher than that of their respective independent examinations(P<0.05).There was significant difference in the degree of differentiation in the clinical features of patients with early gastric cancer and precancerous lesions(P<0.05).The area under the curve(AUC)of ME-NBI for the diagnosis of early gastric cancer and precancerous lesions was 0.853,the accuracy was 85.64%,the sensitivity was 88.37%,and the specificity was 83.62%.The AUC of acetate-indigo rouge staining for the diagnosis of early gastric cancer and precancerous lesions was 0.814,the accuracy was 81.68%,the sensitivity was 83.72%,and the specificity was 80.17%.The AUC of multi-slice spiral CT for the diagnosis of early gastric cancer and precancerous lesions was 0.804,with an accuracy of 80.69%,a sensitivity of 82.56%,and a specificity of 79.31%.And the AUC of the three methods combined to diagnose early gastric cancer and precancerous lesions was 0.893,with an accuracy of 89.60%,a sensitivity of 93.02%,and a specificity of 87.07%.Conclusion ME-NBI,acetate-indigo rouge staining combined with multi-slice spiral CT has high diagnostic efficacy in early gastric cancer and precancerous lesions,and can be used in clinical practice.

Objective To explore the role of an artificial intelligence(AI)model based on real-time object detection network in fetal facial ultrasound examination.Methods With the normal fetal facial ultrasound standard plane(FFUSP)at 20-24 weeks of gestation as the research object,a FFUSP recognition model based on real-time object detection network was constructed.The recognition accuracy of the model for FFUSP and the anatomical structures were analyzed,and the clinical value was evaluated by analyzing its performance in identifying FFUSP in 119 cases of fetal ultrasound images.Results The overall precision,recall rate,mAP@.5 and mAP@.5:.95 of the AI model were 97.8%,98.5%,98.1%and 61.0%,respectively.The clinical validation showed that the AI model had a sensitivity,specificity,positive predictive value,negative predictive value and accuracy of 100.0%,98.5%,87.4%,100.0%and 98.7%for facial anatomy recognition,and the results were highly consistent with the classification of fetal ultrasound experts(k=0.925,P<0.001).The recognition accuracy of the model for 3 types of standard planes reached 100%;and the average speed of dynamic video detection was 33.93 frames per second.Conclusion The FFUSP recognition model based on real-time object detection network exhibits excellent performance,and it can be applied to real-time ultrasound diagnosis,teaching and intelligent quality evaluation.

Objective:To investigate the correlation between the neoadjuvant rectal (NAR) score and long-term survival in patients with locally advanced rectal cancer who have undergone neoadjuvant chemoradiotherapy.Methods:Clinical and pathological data of 487 patients diagnosed with rectal adenocarcinoma from October 2004 to April 2014 at Sun Yat-sen University Cancer Center who had received neoadjuvant chemoradiotherapy were retrospectively analyzed and the impact of NAR score on prognosis studied. Disease-free-survival (DFS) was calculated by the Kaplan-Meier method and survivals compared using the log-rank test. Cox models were used for univariate and multivariate analyses. Receiver operating characteristic curves were utilized to evaluate the predictive capability of NAR and tumor regression grade scores for the risk of 10-year postoperative recurrence and metastasis. The Delong test was employed to compare the diagnostic performance of the two scores.Results:Of the 487 patients included in the study, 166 were men (34.1%). The median age was 56 years (interquartile range [IQR]: 46–63). All patients completed adequate preoperative chemoradiotherapy and underwent R0 resection.The median interval between the end of chemoradiotherapy and surgery was 51 days (IQR: 44–58). Post-chemoradiotherapy downstaging occurred in 329 patients (67.6%). Tumor regression grades (TRGs) were 1–2 in 246 patients (50.5%) and 3–4 in 241 patients (49.5%). A total of 394 patients (80.9%) received postoperative chemotherapy. NAR scores were <8 in 182 patients (37.4%), 8–16 in 180 (37.0%), and >16 in 125 (25.6%). The median follow-up time was 111.5 months (IQR: 70.7–133.7 months). One hundred and thirteen patients died of rectal cancer, among whom 13 patients developed local recurrence, 88 patients developed distant metastasis, and 12 patients had unknown recurrence patterns. The 10-year DFS and overall survival rate of f the whole group were 68.9% and 71.5% respectively. The 10-year DFS rates for patients with NAR scores <8, 8–16, and >16 were 85.1%, 80.5%, and 66.4%, respectively ( P<0.001). Multivariate analyses revealed that the Dixon operation (HR=0.606, 95%CI: 0.408–0.902, P=0.014), and >16 (HR=2.569, 95%CI: 1.559–4.233, P<0.001) were independent predictors of the 10-year DFS of patients with locally advanced rectal cancer ( P<0.05 for all). In the entire patient cohort, the AUC of the receiver operating characteristic curve for NAR score predicting 10-year recurrence and metastasis was 0.67 (95%CI: 0.62–0.72), whereas the AUC for TRG score was 0.54 (95%CI: 0.49–0.60). The two scores differed significantly in accuracy ( Z=-4.06, P<0.001), the NAR score being a significantly better predictor of risk of 10-year recurrence and metastasis than the TRG score. Conclusion:The NAR score is a reliable predictor of 10-year DFS in patients with locally advanced rectal cancer who have undergone neoadjuvant chemoradiotherapy followed by curative surgery.

Objective:To seek the optimal melanin-removal method for hematoxylin and eosin (HE) staining, immunohistochemistry and molecular detection.Methods:Thirty-eight paraffin tissue samples of malignant melanoma diagnosed at the Fujian Cancer Hospital, Fuzhou, China between January 2018 and March 2022 were collected and used to make a tissue microarray. Melanin in these cases was removed using warm hydrogen peroxide, double oxidation depigmentation, modified potassium permanganate-oxalic acid or trichloroisocyanuric acid, followed by HE staining. The cases were divided into two cohorts: one was subject to the one of the above four methods to remove melanin first, followed by immunohistochemistry (SOX-10, Ki-67, HMB45 and Melan A), while the other was subject to immunohistochemical staining first and then a melanin removal. Following that, seventeen melanin-rich paraffin tissue samples were collected and depigmented using the methods described above. DNA extraction was then done, followed by assessments of DNA content and quality. Moreover, the completeness of melanin removal, the effect on HE and immunohistochemical staining, and the quality of DNA were compared between the depigmented methods.Results:Regarding the effectiveness of melanin removal, the modified potassium permanganate-oxalic acid and the warm hydrogen peroxide methods were the most effective, and both showed residual melanin in only 5.26% (2/38) of the cases. The trichloroisocyanuric acid method showed residual melanin in 10.53% (4/38) of the cases. The worst was the double oxidation depigmentation method, which showed pigment residue in 15.79% (6/38) of the cases. For HE staining, the percentage of good staining with the warm hydrogen peroxide method was 92.11%, higher than the other three methods. For immunohistochemical staining, the mean staining scores of immunohistochemistry first followed by melanin removal with modified potassium permanganate-oxalic acid, double oxidation and trichloroisocyanuric acid were 20.84, 26.63 and 35.02, respectively. These immunohistochemical staining scores were higher than those of melanin removal first followed by immunohistochemistry (8.70, 15.41 and 21.22, respectively). The mean staining score of melanin removal by warm hydrogen peroxide method followed by immunohistochemistry was 33.57, superior to that of immunohistochemistry followed by the melanin removal (19.96). Moreover, the staining scores of HMB45, MelanA and Ki-67 with immunohistochemical staining followed by trichloroisocyanuric acid method were 36.45, 33.79, and 36.24, respectively, while the staining score of SOX10 with melanin removal by warm hydrogen peroxide followed by immunohistochemistry was 34.39. The DNA was significantly degraded by modified potassium permanganate-oxalic acid, double oxidation depigmentation and trichloroisocyanuric acid, whereas the mean concentration of DNA extracted after melanin removal by hydrogen peroxide method was 59.59 μg/L, substantially higher than that of DNA extracted without melanin removal (30.3 μg/L, P=0.001). The A260/ A280 of DNA extracted after melanin removal by hydrogen peroxide was between 1.8 and 2.0 in all cases, and the A260/ A230 was above 2.0 in sixteen cases, suggesting high purity of DNA. However, the DNA extracted without removing the melanin showed poor purity, with A260/ A280 below 1.8 in eight cases and A260/ A230 below 2.0 in sixteen cases. Conclusions:Warm hydrogen peroxide showed the least melanin residue, superior HE staining and a minimal effect on DNA purity/quality compared to the other three methods. It thus appears most suitable for PCR, NGS and other molecular detection. Melanin removal with trichloroisocyanuric acid after immunohistochemical staining has the least melanin residual, and thus could be the most convenient and efficient. However, it is noted that the efficacy of the same depigmentation method varies with different antibodies. Therefore, the optimal depigmentation method should be selected based on the specific markers of interest.

Objective To investigate the relationship between vitamin K2,insulin-like growth factor bind-ing protein 3(IGFBP-3),Omentin-1 and the therapeutic effect on children with idiopathic short stature(ISS),and to build a prediction model.Methods A total of 242 ISS children in Jinan Second Maternal and Child Health Hospital from 2019 to 2021 were selected.All of them received recombinant human growth hormone(rhGH)treatment and were divided into effective group and ineffective group according to the therapeutic effect after 12 months of treatment.The general data,vitamin K2,IGFBP-3 and Omentin-1 in the two groups were analyzed.The influencing factors of ISS children's therapeutic effect were analyzed by Logistic regression model and decision tree model.The predictive performance of two models was analyzed by using receiver oper-ating characteristic(ROC)curve.Results There were statistically significant differences in 25-hydroxy vita-min D[25(OH)D],parathyroid hormone(PTH),thyroid stimulating hormone(TSH),vitamin K2,IGFBP-3,Omentin-1,rhGH dosage and weekly outdoor exercise time between the two groups(P＜0.05).Logistic re-gression showed that PTH(OR=7.011,95％CI:2.456-20.014),vitamin K2(OR=0.605,95％CI:.0.465-0.788),IGFBP-3(OR=0.458,95％CI:0.321-0.654),Omentin-1(OR=0.514,95％CI:0.389-0.679)and rhGH dose(OR=0.563,95％CI:0.445-0.712)]were the influential factors for treatment ineffectiveness in ISS children(P＜0.05).The decision tree model showed that vitamin K2,IGFBP-3 and Omentin-1 were the factors influencing the therapeutic effect of ISS,and IGFBP-3 had the most significant impact.ROC curve re-sults showed that the area under the curve of decision tree model and Logistic regression model were 0.922 and 0.908,respectively,with good classification effect.Conclusion The therapeutic effect of ISS children is in-fluenced by factors such as vitamin K2,IGFBP-3,Omentin-1,and so on,and IGFBP-3 has the most significant impact.Logistic regression model and decision tree model could complement each other so as to provide refer-ence for improving the therapeutic effect of ISS children from different aspects.

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.

Metabolomics, including targeted metabolomics and non-targeted metabolomics, is a method to study endogenous small molecule metabolites in organisms. The process of metabolomics analysis generally includes sample collection and pre-treatment, sample detection, data preprocessing, metabolite identification, data statistical analysis, and others. At present, metabolomics technology has been applied to study toxicological mechanism of occupational hazards, early detection and diagnosis of occupational diseases, screening biomarkers of occupational exposure, and others. The application of metabolomics technology to explore the relationship between workers' metabolites and exposure to occupational hazardous, assess the potential impact of occupational exposure on workers' health, and search for ideal biomarkers or therapeutic targets is conducive to early warning and monitoring of occupational health hazards, and assistance in the early diagnosis and prognosis of occupational diseases.In the future, further research is needed in the field of occupational health using metabolomics to establish more complete and standardized workflows and experimental methods, combine big data technology to explore potential biomarkers, utilize metabolic information to provide precise occupational health services, and use artificial intelligence models for data mining and disease diagnosis in metabolomics.