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.

ObjectiveTo investigate pulmonary function levels and associated influencing factors among rural elderly in Guangzhou， to identify high-risk populations for poor pulmonary function， and to reveal the relationship between the influencing factors of pulmonary function. MethodsWe recruited 1 500 residents aged 60 to 94 years from rural area of Conghua District， Guangzhou City using convenience sampling in 2023. Data on demographics， body measurements， medical history and lifestyle were collected via face-to-face questionnaires and physical examination. Meanwhile， expiratory function parameters including forced expiratory volume in one second （FEV1）， forced vital capacity （FVC）， FEV1/FVC， and the prevalence of airflow obstruction （AFO） were assessed using a portable spirometer. Age and sex distribution of pulmonary function in older adults at 5-year intervals was reported， and risk factors of AFO using multifactorial logistic regression models were analyzed. Furthermore， path analysis was further employed to explore the role of lifestyle in the association between other influencing factors and lung function. ResultsAmong the 1 500 participants， the median age was 71 years （67-75）， and 44.2% were male. Subjects identified as AFOs were generally older， more likely male， less educated， and had lower rates of moderate to vigorous physical activity （＜1 time/week） and lower lean body mass. Mean FEV1/FVC ratio was （82.0±16.4） %. FEV1/FVC was （79.80±17.58） % in men and （83.66±15.22） % in women. Older age， lower education， male sex and leanness were negatively associated with all pulmonary function outcomes （all P values＜0.05）. Path analysis identified that age， gender， marital status， occupation and income may influence pulmonary function indirectly through lifestyle. ConclusionRural elderly in Guangzhou exhibited lower pulmonary function levels， and male sex， non-married status， advanced age， lower education， smoking habits， insufficient engagement in moderate to vigorous physical activity， and lean body type were all associated with worse pulmonary function.

【Objective】 To explore the feasibility of en-bloc resection of bladder tumors by flexible cystoscope combined with laparoscopic instruments through urethra and to provide reference for the clinical application of this technique. 【Methods】 Self-designed and processed transurethral single-hole PORT and Olympus electronic cystoscope were used as observation mirror; Φ1.8 mm soft grasper, tissue scissors, electric hook, and ultrasonic scalpel were used as instruments; the porcine bladder was used as a model.The PORT was placed through the urethra, and the cystoscope was inserted to observe the inner wall of the bladder and the condition of the mucosa.After the lesion site was identified in the bladder cavity, the soft grasper was inserted to pull the mucosa to be removed, which was then fixed with tension at the target position to maintain a satisfactory feild of view.The surgeon held the cystoscope in the left hand, and operated the laparoscopic instruments into the bladder cavity through the PORT with the right hand.Observing with the cystoscope and lifting and pulling the mucosa with the grasper, the surgeon simulated the cutting and pushing actions to realize the en-bloc resection of the lesioned mucosa. 【Results】 The mucosa at 4 different locations were successfully resected on 2 in vitro porcine bladder models. 【Conclusion】 The in vitro experiments show that the combination of flexible electronic cystoscope and laparoscopic instruments achieves synergistic effects in en-bloc resection of bladder tumor by transurethral single-hole laparoscope without additional iatrogenic bladder injury caused by percutaneous bladder incision.This method is feasible in the treatment of bladder tumors, and has the potential of clinical application after further optimization.

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.

Clarifying the applicability （indications or contraindications） of traditional Chinese medicine （TCM） dietary regimens to different syndromes is a guarantee for the rational application and safety of TCM dietary therapy. By considering evidence from ancient literature， modern research and experts' experience， the Grading System for Syndrome Suitability of Dietary Therapy in TCM （GRADE-SSD） has been constructed. According to the currently available highest-quality evidence， GRADE-SSD classified the applicability of TCM dietary therapy to various TCM syndromes into 2 categories and 4 grades： "definitely" applicable/contradicted （Grade A）， "very likely" applicable/contradicted （Grade B）， "possibly" applicable/contradicted （Grade C）， and insufficient evidence to determine （Grade D）. When applying， first， systematically search the currently available ancient books and clinical research evidence. For different types of evidence （ancient TCM books， randomized controlled trials， observational studies， and meta-analyses）， use the prescribed tools to evaluate the quality of the evidence， and then determine the applicability level of TCM syndromes of dietary therapy based on the principle of "taking the highest" quality. If there is a lack of direct evidence， GRADE-SSD supports a downgraded evaluation based on indirect evidence of "similar prescriptions". When there is a lack of ancient books and clinical research， the GRADE-SSD plan can evaluate the quality of evidence from peer consensus or expert opinions for the applicability level of TCM syndromes of dietary therapy. Based on the requirements for the safety of TCM dietary therapy， when there is both "applicable" and "contradicted" evidence， it should be considered as "contradicted" evidence. GRADE-SSD also provides an evidence certainty update plan based on new evidence in the future. The evaluation results of GRADE-SSD can provide a basis for setting inclusion/exclusion criteria in clinical trials of TCM dietary therapy and stating the applicability of each syndrome in the labels of dietary therapy products.

Objective To investigate the characteristics of pulmonary artery diameter in patients with human immunodeficiency virus(HIV)infection-associated pulmonary hypertension(PAH),and to explore the clinical significance of pulmonary artery diameter correlation indices combined with tumor necrosis factor-α(TNF-α)for early screening and diagnosis of HIV-associated pulmonary hypertension,aiming to provide valuable clinical insights.Methods A retrospective analysis was conducted on 65 HIV-infected patients admitted to the Eighth Hospital Affiliated to Guangzhou Medical University between May 2017 and December 2023.Based on echocardiog-raphy findings,the patients were categorized into an observation group(23 cases with PAH)and a control group(42 cases without PAH).Measurements of pulmonary artery diameter(PA),distal pulmonary artery diameter(dPA),and aortic diameter were obtained in both groups,and the ratio of dPA to aortic diameter(rPA)was cal-culated.Additionally,serum TNF-α levels were recorded.The clinical significance of each index in early screening and diagnosis of HIV-related pulmonary hypertension was analyzed.Results The PA,dPA,rPA,and TNF-α levels in the observation group were significantly higher compared to those in the control group.Pearson linear correlation analysis revealed a significant positive correlation between TNF-α and both dPA and rPA.Two-column correlation analysis demonstrated a significant association between HIV-PAH and PA,dPA,rPA,as well as TNF-α(P<0.05).The combined measurement of serum TNF-α with dPA and rPA exhibited an area under the curve(AUC)of 0.891 for diagnosing HIV-APAH,with a sensitivity of 0.870 and specificity of 0.881.Conclusion The combination of pulmonary artery diameter and TNF-α provides a more accurate indication of the presence of HIV-PAH,enabling early screening,follow-up,or intervention in high-risk patients.This finding holds significant implications for enhancing patient prognosis.

Objective:To explore the effects of computer-navigated surgery and traditional surgery on the functional and oncological outcomes of pelvic chondrosarcoma.Methods:Retrospective analysis of 136 cases of pelvic chondrosarcoma surgically treated at Beijing Jishuitan Hospital from January 2000 to December 2017. There were 65 males and 71 females with an average age of 46.07±13.37 years (range 13-73 years). There were 120 primary cases and 16 secondary cases, of which 109 cases were ordinary chondrosarcoma (7 cases with pathological differentiation grade I, 83 cases with grade II. There were 109 cases of common type chondrosarcoma (7 cases of pathological differentiation grade I, 83 cases of grade II, 19 cases of grade III), 21 cases of dedifferentiated chondrosarcoma, 3 cases of mesenchymal type, 2 cases of clear cell type, 1 case of mucinous type; 12 cases of malignant degeneration of multilocular chondrosarcoma of bone; 104 cases of Enneking staging stage IB, 32 cases of stage IIB. According to the pelvis zone classification, there were 14 cases of pelvic zone I, 1 case of zone II, 13 cases of zone III, 16 cases of zone I+II, 16 cases of zone I+IV, 47 cases of zone II+III, 25 cases of zone I+II+III, 25 cases of zone I+II+III, 4 cases of zone I + II + III + IV. All cases were classified as intracapsular, marginal, or wide resection according to the resection boundary classification. There were 45 cases in computer-navigated surgery (navigated group) and 91 cases in non-navigated surgery group. The demographic data, preoperative tumor staging, surgical characteristics, surgical boundary classification, oncological indexes, reconstruction methods, postoperative complications, and bone and soft tissue tumor function score (Musculoskeletal Tumor Society score, MSTS) were compared between the two groups.Results:No surgical complications related to the computerized navigation system occurred in the navigation group. The postoperative follow-up time was 68.56±37.82 months (range 6-197 months) and 76.85±52.60 months (range 5-225 months) for the navigation and non-navigation groups, respectively. The MSTS was 25.43±2.85 and 24.56±4.19 points in the navigation and non-navigation groups, respectively, with no significant difference ( t=1.191, P=0.237). There were 10 cases of marginal resection and 35 cases of wide resection in the navigation group, and 12 cases of intracapsular resection, 32 cases of marginal resection and 47 cases of wide resection in the non-navigation group with significant difference (χ 2=10.977, P=0.004). There were 4 cases (8.9%, 4/45) of local recurrence after surgery in the navigation group and 20 cases (21.9%, 20/91) in the non-navigation group, with significant difference (χ 2=4.040, P=0.046). There were 2 cases of final amputation and 2 cases of re-excision with recurrence in the navigation group and 6 cases of final amputation and 14 cases of re-excision in the non-navigation group. Distant metastases occurred in 3 cases (7%, 3/45) in the navigation group and 18 cases (20%, 18/91) in the non-navigation group wtih significant difference (χ 2=4.478, P=0.034). The five-year postoperative survival rates of the navigation and non-navigation groups were 93.3% and 72.6%, and the three- and five-year progression-free survival rates were 91.1% and 84.4% and 74.8% and 62.7%, respectively, with significant differences (χ 2=5.081, P=0.024; χ 2=6.800, P=0.009). The five-year survival rate of stage IB tumors was 96.7% in the navigation group and 84.5% in the non-navigation group with significant difference (χ 2=3.897, P=0.048); the five-year survival rate of stage IIB tumors was 75.0% in the navigation group and 35.0% in the non-navigation group with no significant difference ( P>0.05). Postoperative complications included 15 cases of postoperative infection, 16 cases of deep vein thrombosis, 14 cases of double lower limb inequality, 2 cases of prosthesis dislocation, 2 cases of lymphedema, 1 case of hernia and 1 case of allograft bone resorption. There was no significant difference of complication rates between the two groups ( P>0.05). Conclusion:Computer navigation-assisted resection of pelvic chondrosarcoma was better in obtaining a safe surgical border of the tumor compared with traditional surgery, reducing the rate of local recurrence of the tumor and thus effectively improved the survival and prognosis of patients.

Objective:To analyze the prognostic factors and the influence of surgical margin to prognosis.Methods:A retrospective analysis was performed for 208 pelvic tumors who received surgical treatment from January 2000 to December 2017 in our instituition. Survival analysis was performed using the Kaplan-Meier method and Log rank test, and impact factor analysis was performed using Cox regression models.Results:There were 183 initial patients and 25 recurrent cases. According to Enneking staging, 110 cases were stage ⅠB and 98 cases were stage ⅡB. 19 lesions were in zone Ⅰ, 1 in zone Ⅱ, 15 in zone Ⅲ, 29 in zone Ⅰ+Ⅱ, 71 in zone Ⅱ+Ⅲ, 29 in zone Ⅰ+Ⅳ, 35 in zone Ⅰ+Ⅱ+Ⅲ, 3 in zone Ⅰ+Ⅱ+Ⅳ, and 6 in zone Ⅰ+Ⅱ+Ⅲ+Ⅳ. Surgical margins including Intralesional excision in 7 cases, contaminated margin in 21 cases, marginal resection in 67 cases, and wide resection in 113 cases. Local recurrence occurred in 37 cases (17.8%), 25 cases were performed by reoperation and 12 cases received amputation finally. The 5-year recurrence rate of marginal resection was higher than wide resection ( P＜0.05), and the recurrence-free survival rate of marginal resection was lower than wide resection ( P＜0.05). There was significant differences in recurrence rate and recurrence-free survival rate between R0 and R1 resection ( P＜0.05). 92 cases were not reconstructed and 116 cases were reconstructed after pelvic surgery. At the last follow-up, 63 patients (30.3%) died, and the 5-year, 10-year and 15-year survival rates were 70.4%, 66.8% and 61.3%, respectively. The 5-year survival rate of stage ⅠB and ⅡB tumor was 90.4% and 46.8%, respectively. There were 29 cases had postoperative wound complications (13.8%), 1 case with pelvic organ injury. The final function was evaluated in 132 patients, with an average MSTS score of 25.1±3.6. Cox multivariate analysis showed that surgical staging, R0/R1 margin and metastasis were independent prognostic factors for pelvic tumors. Conclusions:The safe surgical margin is the key factor for recurrence-free of pelvic tumor. The survival rate of stage ⅡB pelvic tumors was significantly lower than that of stage ⅠB tumors. Wound infection is the main postoperative complication. Surgical staging, R0/R1 margin and metastasis were independent prognostic factors of pelvic tumors.