The core idea of occupational health risk assessment models is to systematically evaluate occupational health risks according to target hazard characteristics and relevant exposure levels of workers. Occupational exposure assessment is based on concentration, frequency, exposure time, and other indicators that indicate actual exposure of workers to occupational hazards, which is a critical component of health risk assessment. However, the accuracy and comparability of assessment results are affected by differences in parameter assignment for exposure assessment across different studies, as well as insufficient emphasis on multiple occupational hazard exposure. This review aimed to explore the assignment and standardization of exposure assessment parameters for occupational health risk assessment modeling, and systematically sorted out the meaning, assignment methods, and sources of exposure assessment related parameters in commonly used occupational health risk assessment models, with the goal of providing researchers with standardized assessment tools to enhance the scientific rigor and practicality of occupational health risk assessments. Considering the individual differences and temporal fluctuations in occupational exposure, it is recommended that researchers should adopt appropriate sampling strategies, reasonably select sample subjects and time based on the division of similar exposure group (SEG), and conduct statistical inference on the obtained data to derive representative exposure parameters. For combined exposure to chemicals with similar toxic effects, the health risk assessment methods are relatively mature. However, the assessment of combined exposure to hazards with different properties and health effects still lacks scientific authority and needs further research and discussion.

Background Coal workers' pneumoconiosis is a serious occupational disease in China. Exhaled volatile organic compounds (VOCs) can serve as the "breath fingerprint" of internal pathological processes, which provides a theoretical basis for exhaled VOCs to be used as potential non-invasive biomarkers for early diagnosis of coal workers' pneumoconiosis. Objective To screen out the characteristic VOCs and important characteristic VOCs of exhaled air in patients with coal workers' pneumoconiosis, and to explore the potential of these VOCs as biomarkers for early non-invasive diagnosis of the disease. Methods In this study, 27 VOCs in the exhaled breath of 22 patients with stage I coal workers' pneumoconiosis, 77 workers exposed to dust, and 92 healthy controls were quantitatively detected by thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). Substances with P<0.05 in univariate analysis and variable importance projection (VIP) >1 in supervised orthogonal partial least squares discriminant analysis (OPLS-DA) model were selected as the characteristic VOCs for early diagnosis of coal workers' pneumoconiosis. Age was included in the LASSO regression model as a covariate to screen out important characteristic VOCs, and the diagnostic performance was evaluated by receiver operating characteristic (ROC) curve. Spearman correlation was further used to explore the correlation between important characteristic VOCs and clinical lung function indicators. Results Through univariate analysis and OPLS-DA modeling, 8 VOCs were selected, including 2-methylpentane, 3-methylpentane, n-hexane, methylcyclopentane, n-heptane, methylcyclohexane, 4-methyl-2-pentanone, and 2-hexanone, in exhaled breath of patients with coal workers' pneumoconiosis. The concentrations of 4 VOCs, including 3-methylpentane, n-hexane, 4-methyl-2-pentanone, and 2-hexanone, showed a decreasing trend with the increase of dust exposure years. By LASSO regression, the important characteristic VOCs of the coal workers' pneumoconiosis group and the dust exposure group were n-hexane, methylcyclohexane and 4-methyl-2-pentanone, and the important characteristic VOCs of the coal workers' pneumoconiosis group and the healthy group were 2-methyl-pentane and 4-methyl-2-pentanone. The ROC analysis showed that the area under the curve (AUC) of n-hexane, methylcyclohexane, and 4-methyl-2-pentanone were 0.969, 0.909, and 0.956, respectively, and the AUC of combined diagnosis was 0.988 and its Youden index was 0.961, suggesting that these results can serve as a valuable reference for further research on early diagnosis. The Correlation analysis found that there was a positive correlation between n-hexane and lung function indicators in the important characteristic VOCs, indicating that it could indirectly reflect the obstruction of lung function ventilation, further proving that important characteristic VOCs have the potential to monitor lung function decline. Conclusion Three important characteristic VOCs selected in this study have the potential to be used as non-invasive biomarkers for early diagnosis and disease monitoring of coal workers' pneumoconiosis, and are worthy of further study and verification.

Background and aims:Despite growing evidence linking pretransplant exposure to immune checkpoint inhibitors(ICIs)to increased allograft rejection risk after liver transplantation(LT),a lack of comparative studies to definitively establish the correlation between ICI exposure and adverse short-term outcomes after LT exists.This study aimed to analyze the impact of preoperative ICI exposure on short-term post-LT prognosis and allograft rejection risk.Methods:This retrospective cohort study included 121 recipients who underwent LT for hepatocellular carcinoma(HCC)between June 2019 and March 2023.The recipients were categorized into ICI(n=35)and non-ICI(n=86)exposure groups based on pretransplant ICI exposure.Demographics,clinical characteristics,and short-term outcomes were compared between the cohorts.Kaplan-Meier analysis evaluated the impact of ICI exposure on graft survival.Univariate and multivariate logistic regression models assessed the impact of patient characteristics on allograft rejection.Results:Recipients with or without ICI exposure exhibited comparable demographic baseline charac-teristics.The incidences of early allograft dysfunction and biliary and vascular complications were similar between both groups.Post-transplant infection incidence was 37.1％and 20.9％in the ICI and non-ICI groups,respectively(P=0.064).Allograft rejection rates were significantly higher in the ICI group than in the non-ICI group(22.9％vs.5.8％,P=0.015).The ICI group exhibited a higher 90-day post-transplant mortality rate than that of the non-ICI group(14.3％vs.2.3％,P=0.034).Logistic regression analyses demonstrated that allograft rejection independently correlated with 90-day post-transplant mortality,with ICI exposure being an independent risk factor for allograft rejection.In recipients with ICI exposure,a shorter interval between ICIs and LT(washout period)was significantly associated with a higher allograft rejection risk,with the optimal washout period identified as 21 days for predicting 90-day rejection-free survival(P=0.0001).Moreover,in recipients with allograft rejection,the peripheral CD4+/CD8+T cell ratio was much lower in the ICI group than in the non-ICI group.Conclusions:Pretransplant ICI exposure was an independent risk factor for allograft rejection and was significantly associated with 90-day post-transplant mortality after LT for HCC.A ≤21-day washout period was significantly associated with allograft rejection.Future multicenter studies with larger cohorts and prospective designs are essential to validate these findings,confirm causality,and establish standardized clinical guidelines for ICI use before transplantation.Trail registration:ClinicalTrials.gov NCT05913583.

The composition and concentration of volatile organic compounds (VOCs) in exhaled breath are closely related to human health and the analysis of VOCs by collecting human exhaled breath has been widely used in disease surveillance research. This article reviewed the collection, enrichment, and detection methods of exhaled VOCs, which can provide a reference for selecting appropriate technology for follow-up research. The exhaled breath collection devices mainly include sampling bags for mixed exhaled breath and biological volatile organic compound (Bio-VOC) samplers for alveolar air. The pre-enrichment equipment included thermal desorption (TD), solid-phase microextraction device (SPME), and needle trap device (NTD). The detection methods of exhaled VOCs include gas chromatography-mass spectrometry (GC-MS), proton transfer reaction mass spectrometry (PTR-MS), selective ion flow tube mass spectrometry (SIFT-MS), and electronic nose. At present, the collection and enrichment technology of exhaled breath is not mature yet, and its influence on the results of detection is lack of evaluation. In the future, the research on collection and enrichment technology of exhaled breath should be strengthened to further promote the application of exhaled breath in disease surveillance research.

Occupational pneumoconiosis (referred to as “pneumoconiosis”) caused by exposure to occupational dust is the most serious occupational disease in China. Biological monitoring on occupational populations exposed to dust is important for the prevention, diagnosis, and treatment of pneumoconiosis. Biological monitoring is a systematic engineering process that includes a series of processes such as biological samples selection, selection of biological monitoring indicators, and selection of detection methods. The biological samples for biological monitoring mainly include urine, blood, exhaled breath gas, bronchoalveolar lavage fluid, saliva, sputum, and more. The indicators of biological monitoring involve multiple pathways such as oxidative stress, inflammatory response, collagen synthesis/degradation, phagocytic cell apoptosis, and pathways related to the formation of pneumoconiosis. Suitable detection methods need to be determined upon different biological monitoring indicators, including enzyme-linked immunosorbent assay, high-performance liquid chromatography, high-performance liquid chromatography-tandem mass spectrometry, inductively coupled plasma mass spectrometry, etc. Currently, there is a lack of true clinically valuable biological monitoring indicators that can indicate the correlation between dust exposure and the hazards of occupational populations, and there are no systematic and complete biological monitoring methods reported. It is necessary to further standardize the biological monitoring process and search for specific biological monitoring indicators.

Objective: To analyze the impact of persistent obesity on their lung function, so as to offer insights for implementing intervention measures to increase lung function in obese school age children. Methods: A total of 335 children from the Sheyang Mini Birth Cohort established in 2009 in Yancheng City, Jiangsu Province, who participated in the follow up at the ages of 7 years (2016) and 10 years (2019), were selected as the study participants. Physical measurements including height, weight, and lung function were recorded. According to the World Health Organization standard, that is, gender and age specific to correct the body mass index to calculate the body mass index Z score, was used to evaluate the obesity status of children at the age of 7 and 10. Children were divided into four groups, including sustained non obesity group, restored obesity group, newly classified obesity group, and persistent obesity group. Meanwhile, the lung function prediction equations recommended by the Global Lung Function Initiative were used to standardize the lung function indexes of children. Pulmonary function differences among these groups were examined, and the relationship between childhood obesity and pulmonary function was longitudinally analyzed using generalized estimating equations. Results: The prevalence of obesity were 9.0% and 16.1% at the age of 7 and 10 years, respectively. The proportion of both newly classified and persistent obesity group were 8.1%, respectively. The forced expiratory volume in one second (FEV 1) and forced vital capacity (FVC) were (1 269.90±202.70) and (1 415.70±230.00) mL, respectively, at the age of 7 years. FEV 1 and FVC at the age of 10 years were (1 440.80±403.20) and (1 555.60±517.60) mL, respectively. Cross sectional analysis at age 7 showed that forced expiratory flow at 75% vital capacity (FEF 75 ) ( β=-0.52, 95%CI =-0.96--0.07) and maximal mid expiratary flow (MMEF) ( β=-0.45, 95%CI =-0.89--0.00) were significantly lower in obese children compared to their non obese peers ( P < 0.05). Longitudinal analysis indicated that obese children had lower levels of lung pulmonary function, with a statistically significant difference in FEV 1 ( β=-0.44, 95%CI=-0.85--0.02, P <0.05). There was no significant difference among the various obesity groups ( P >0.05), while gender stratified results revealed significant reductions in FEV 1/FVC in newly classified obese girls at age 10 years ( β=-1.76, 95%CI =-3.13--0.38) and in MMEF in persistently obese girls at age 10 years ( β=-1.44, 95%CI = -2.79- -0.09) ( P <0.05). Conclusion Obesity may contribute to reduced lung function levels in school aged children, with newly classified and persistent obesity having more pronounced effects on lung function in girls.

Objective To compare the difference of volatile organic compounds (VOCs) in the urine of diabetic patients comorbid with or without depression. Methods Patients with type 2 diabetes who met the diagnostic criteria of prevention and treatment guidelines and were treated in inpatient department of Sixth People’s Hospital South Campus, Shanghai Jiaotong University, from November 2019 to November 2020 were included in the study. Depression screening was performed using PHQ9 scale. According to the scores, the patients were divided into two groups: diabetic patient group and diabetic patient comorbidity depression group. The morning urine was collected and VOCs in urine were detected using a miniature gas tester. Results A total of 161 patients with diabetes mellitus, including 141 patients in the diabetic group and 20 patients in the diabetic comorbidity depression group. The results indicated that the sensitivity, specificity and accuracy of the method are 80%, 98% and 92.8% respectively. There were differences in urine volatile organic compounds between the two groups. Conclusions Compared with diabetic patients, the composition of volatile organic compounds in urine may change after diabetic comorbidity depression, which can provide experimental reference for early clinical diagnosis of depression.

Osteoporotic thoracolumbar fracture in the elderly will seriously reduce their quality of life and life expectancy. For osteoporotic thoracolumbar fracture in the elderly, spinal reconstruction is necessary, which should comprehensively consider factors such as the physical condition, fracture type, clinical characteristics and osteoporosis degree. While there lacks relevant clinical norms or guidelines on selection of spinal reconstruction strategies. In order to standardize the concept of spinal reconstruction for osteoporotic thoracolumbar fracture in the elderly, based on the principles of scientificity, practicality and progressiveness, the authors formulated the Clinical guideline for spinal reconstruction of osteoporotic thoracolumbar fracture in elderly patients ( version 2022), in which suggestions based on evidence of evidence-based medicine were put forward upon 10 important issues related to the fracture classification, non-operative treatment strategies and surgical treatment strategies in spinal reconstruction after osteoporosis thoracolumbar fracture in the elderly, hoping to provide a reference for clinical treatment.

Objective:To document any improvement in the breathing control of stroke survivors with dysarthria after practicing Liuzijue qigong.Methods:A total of 157 stroke survivors with dysarthria and abnormal respiration control were randomly divided into an observation group and a control group. Both groups were given traditional breathing training and basic articulation training (including articulatory organ training and speech training). The observation group also received training in Liuzijue qigong. It requires inhaling through the nose and exhaling through the mouth while producing the speech sounds xu, he, hu, si, chui and xi. The training lasted two weeks. Both groups were then evaluated using the modified Frenchay dysarthria assessment. Maximum phonation time, maximum counting ability and volume were also recorded as secondary indexes.Results:After the 2-week intervention, significant improvement was observed in the average scores on all of the indexes, with all of the observation group′s average scores except for volume significantly better than those of the control group. The average volume scores were significantly improved, but not significantly different.Conclusion:Supplementing basic articulation training with Liuzijue qigong can improve respiratory function and the speaking ability of stroke survivors with dysarthria. It is worthy of wider clinical application.

Objective:To explore the distribution of pelvic lymph node (PLN) metastasis and the correlative dangerous factors in early cervical cancer patients.Methods:The medical records of 508 patients who underwent extensive hysterectomy and lymphadenectomy for International Federation of Gynecology and Obstetrics (FIGO) stage Ⅰb-Ⅱb cervical cancer in Guizhou Provincial People`s Hospital were reviewed retrospectively.Results:There were 278 patients with stage Ⅰb cervical cancer, 204 patients with stage Ⅱa cervical cancer and 26 patients with stage Ⅱb cervical cancer; the positive rate of lymph node metastasis was 16.7%(85/508), and obturator lymph node metastasis was the most common (56.6%); there were 19 patients with bilateral lymph node metastasis, accounting for 22.35%(19/85); lymph node metastasis occurred 104 times (two times for bilateral simultaneous transfer), and jumping lymph node metastasis accounted for 37.5%(39/104); common iliac lymph node metastasis accounted for 18.3%(19/104). The metastasis rate of patients with stage Ⅱa and Ⅱb (including parametrial, lymph node, ovarian and oviduct metastasis) was higher than that of patients with stage Ⅰb, and the odd ratio ( OR) was 2.30 and 2.48 respectively ( P<0.05); the metastasis rate of patients with moderately differentiated tumors was significantly higher than that of patients with well differentiated and poorly differentiated tumors ( P<0.05). There was no significant difference in the positive rate of pelvic lymph node metastasis among patients with different ages and histological types ( P>0.05); the positive rate of pelvic lymph node metastasis in patients with stage Ⅱa and Ⅱb was higher than that in patients with stage Ⅰb with statistically significant difference ( P<0.05); the positive rate of pelvic lymph node metastasis in patients with moderately differentiated tumors was higher than that in patients with well differentiated and poorly differentiated tumors, with statistically significant difference ( P<0.05). Conclusions:Obturator lymph node metastasis is the most common in cervical cancer. The risk of lymph node metastasis is increased in patients with stage Ⅱa or moderately differentiated tumors. Jumping metastasis is also a common way of metastasis, which suggests that standard and complete lymph node resection is an important measure to ensure the curative effect.