[Study on the applicability of the Brief Job Stress Questionnaire based on classical test theory and item response theory].

Objective: To evaluate the quality and item characteristics of the Brief Job Stress Questionnaire (BJSQ) among employees in manufacturing and service industries. Methods: From December 2021 to December 2022, a total of 2077 employees from 4 manufacturing and service enterprises in Beijing were selected by the method of combining purpose sampling and convenience sampling. The Chinese version of BJSQ was used to carry out a survey on occupational stress from 57 items in 4 dimensions including job stress factors, stress response, social support factors and satisfaction. Classical test theory (CTT) was used to analyze the validity and reliability of the questionnaire. The Semejima hierarchical response model in item response theory (IRT) was used to analyze the differentiation a, difficulty coefficient b and information content of each item. Results: Among the 2077 subjects, the age M (Q(1), Q(3)) was 33 (28, 37) years old, and the working age M (Q(1), Q(3)) was 4 (2, 8) years. There were 723 (34.8%) people in manufacturing industry and 1354 (65.2%) people in service industry. Eleven common factors were extracted by exploratory factor analysis, with a cumulative variance contribution rate of 62.823%, the variance of the common factors of each entry ranging from 0.451 to 0.865, and the range of factor loading values from 0.413 to 0.825, with 5 items having cross-loadings. The results of the validation factor analysis showed that the model fit indexes of root means square error of approximation was 0.055, comparative fit index was 0.950, Tucker Lewis index was 0.948, and standardized root mean square was 0.066. Content validity results showed that the total scores of the Chinese version of the BJSQ were positively correlated with the scores of the 4 dimensions (r(s)=0.487-0.936, P<0.05) . The results of the reliability analysis showed that the Cronbach's alpha coefficient for the total questionnaire was 0.945, and the Cronbach's alpha coefficients of job stress factors, stress response and social support factors were 0.775, 0.957, and 0.830, respectively. The Spearman-Brown coefficient for the total questionnaire was 0.866, and for the 3 dimensions, it was 0.572, 0.882 and 0.772. The results of IRT analysis showed that only 1 of the 57 items had a differentiation a-value<0.30, the difficulty coefficient b-value of each item ranged from -12.02 to 11.09, of which 8 items had a difficulty coefficient that was too high, 3 items had a difficulty coefficient that was too low, and 3 items did not meet the requirements, and the average amount of information in each item ranged from 0.022 to 2.566, and there were 47 items with average amount of information>0.088 (5/57) . Conclusion: The Chinese version of BJSQ has good reliability and validity in the typical occupational groups of manufacturing and service industries in China, and most of the items have good performance, but some items still need to be further improved and optimized or deleted.

[Comparative analysis of work-related musculoskeletal disorders catalogues].

Work-related musculoskeletal disorders (WMSDs) refer to musculoskeletal disorders caused by work or work as the main cause, which are characterized by high prevalence and heavy burden of disease as a global problem. The classification and catalog of occupational diseases is of great significance for guiding the prevention and control of occupational diseases and safeguarding the rights and interests of workers. The types of WMSDs included in the list of occupational diseases vary greatly from country to country, and the regulations on specific pathogenic factors are also inconsistent. By sorting out and analyzing the lists and characteristics of WMSDs at home and abroad, and using the International Statistical Classification of Diseases and Related Health Problems (ICD-10) in occupational health to standardize of WMSDs in various countries, which would lay the foundation for future multi-country WMSDs occupational health registration and disease burden research, and provide a reference for China to revise the WMSDs list.

[Relationship between pesticide exposure and lipid metabolism in population].

Objective: To investigate the effect of pesticides and herbicides on lipid metabolism. Methods: In November 2020, Based on the data of the national health and Nutrition Survey (NHANES) (2011-2014) , select the population aged 20~65 who have demographic information, pesticide use and data of four lipid metabolism indicators [total cholesterol (TC) , triglyceride (TG) , high density lipoprotein cholesterol (HDLC) and low density lipoprotein cholesterol (LDLC) ] (n=3039) . The subjects were divided into insecticide group (320 people) and non insecticide group (2719) according to the use of insecticides, and herbicide group (156 people) and non herbicide group according to the use of herbicides. Results: Among the 3039 subjects, the males and female were 1509 (49.7%) and 1530 (50.3%) respectively. The males age was (39.7±12.0) years and the females age was (40.2±12.0) years The concentration of HDLC in the NHANES (55.4±15.0) mg/dl was lower than that of (58.2±14.2) mg/dL in the non herbicide group (P<0.05) (b=-0.044, P<0.05) . The results showed that the use of herbicides was related to the decrease of HDLC and the increase of LDLC and LDLC/HDLC in female population (b=-0.050, 0.062, 0.067, all P<0.05) . Conclusion: Herbicide exposure can cause the change of lipid metabolism, and the effect on female population is more obvious.

[Refractory ceramic fibers induced changes in serum Clara cell protein 16 and surfactant protein D levels in rats].

Objective: To explore the effect of refractory ceramic fibers (RCFs) on the serum Clara cell protein 16 (CC16) and surfactant protein D (SP-D) levels in Wistar rats. Methods: In October 2020, 96 healthy adult male Wistar rats were randomly divided into control group (equal volume of normal saline) , low-dose group (5 mg/ml RCFs) , medium-dose group (10 mg/ml RCFs) and high-dose group (20 mg/ml RCFs) , and subjected to non-exposure tracheal instillation. After intraperitoneal anesthesia, the rats were instilled with 200 µl of RCFs suspension or normal saline, once every 3 days for a total of 4 times. At 7, 14, 28, and 90 days after exposure, 6 rats were sacrificed by blood sampling through the abdominal aorta. The organs were separated, histopathological changes of lungs were observed and lung injury scores were performed. The contents of serum CC16 and SP-D were determined by enzyme-linked immunosorbent assay (ELISA) . Results: RCFs could cause inflammatory cells in rat lung tissues, widening of the lung septum and destruction of alveolar structure. 7 days after exposure, the lung injury scores of rats in each dose group were higher than control group, and the lung injury score of the high-dose group was higher than low-dose group (P<0.05) . 14 and 90 days after exposure, the lung injury scores of the medium-dose and high-dose groups were higher than control group (P<0.05) . 28 days after exposure, the lung injury score of the high-dose group was higher than control group (P<0.05) . 7 days after exposure, the serum CC16 and SP-D concentrations of rats in the medium-dose and high-dose groups were significantly higher than control and low-dose groups (P<0.05) . 28 days after exposure, the serum CC16 concentrations of rats in the low-dose and medium-dose groups were significantly lower than those of the control and high-dose groups (P<0.05) . After 90 days of exposure, the serum CC16 concentrations of rats decreased with the increase of the exposure dose (F=28.853, P<0.01) , and the concentrations of SP-D increased with the increase of the exposure dose (F=25.636, P<0.01) . Conclusion: RCFs exposure may cause certain damage to rat Clara cells and alveolar-capillary barrier. The severity of lung injury can be indirectly understood through the dynamic changes of serum CC16 and SP-D.

[Influence of oxidative/antioxidative biomarkers and inflammatory cytokines on rats after sub-acute orally administration of titanium dioxide nanoparticles].

OBJECTIVE: To evaluate the sub-acute oral effect of titanium dioxide (TiO2) nanoparticles on the oxidation/antioxidation biomarkers and inflammatory cytokines in blood, liver, intestine, and colon in rats. METHODS: Twenty four 4-week-old clean-grade Sprague Dawley (SD) rats were randomly devided into 4 groups by body weight (n=6, control, low, middle, and high), in which the rats were orally exposed to TiO2 nanoparticles at doses of 0, 2, 10 and 50 mg/kg body weight/day for 28 consecutive days separately. Food intake, body weight and abnormal behaviors during the experiment were recorded. The rats were euthanized on the 29th day. The blood was collected via abdominal aortic method and centrifuged to collect the serum. Tissues from liver, intestine and colon were collected and homogenated. Then enzyme-linked immunosorbent assay (ELISA) and microwell plate methods were used to detect oxidation/antioxidation biomarkers including superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GSH-Px), total mercapto (T-SH), glutathione disulfide (GSSG), malomdialdehvde (MDA) and inflammatory cytokines including interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in the serum, liver, intestine and colon in the rats. RESULTS: Compared with the control group, no significant differences in body weight, food intake and organ coefficients were observed in all the three groups after TiO2 gavage. No significant changes in GSH, GSH-Px, T-SH, and IL-6 were observed. Compared with the control group, significant increase of SOD activity in serum in high dose group, signi-ficant increase of GSSG concentration in intestine in middle and high dose group and significant increase of MDA concentration in liver in low and high dose group were observed. Compared with the control group, a significant increase of TNF-α in liver in middle and high dose group was observed. CONCLUSION: TiO2 nanoparticle can increase antioxidant enzymes activities in blood, increase oxidative biomarkers in liver and intestine, increase inflammatory cytokines in liver in rats after a 28-day sub-acute orally administration. Among blood, liver, intestine, and colon, liver is most sensitive to the toxicity induced by TiO2 nanoparticles, followed by intestine, blood, and colon in sequence.

[Effects of air pollution exposure on olfaction of rats in Beijing].

Objective: To evaluate the effects of exposure of fine particle matter (PM2.5) and ozone (O3) in Beijing as the main pollutants on olfaction of SD rats. Methods: In October 16, 2018, twenty 8-week-old SD rats were randomly divided into two groups, 10 rats in the exposure group and 10 rats in the control group. They were fed in air pollutant exposure system and clean experimental environment respectively, and the concentrations of PM2.5 and O3 in each system were measured. The degree of olfaction damage of SD rats at different feeding time was assessed by using the buried food test (BFT). The difference of BFT time between the two groups was analyzed by performing the repeated measures analysis of variance. Results: The results showed that the concentrations of PM2.5 and O3 in the exposure group were (22.65±11.47) µg/m3 and (12.36±5.87) µg/m3, respectively, while those in the control group were both 0 µg/m3. The repeated measures analysis of variance showed that the time of BFT in the exposure group was longer than that in the control group (F=6.49, P=0.031). With the increase of feeding time, the time of BFT was prolonged (F=61.69, P<0.001). Conclusion: Exposure to PM2.5 and O3 in the atmosphere might lead to olfaction damage in rats.

A 10-year retrospective study of free anterolateral thigh flap application in 872 head and neck tumour cases.

The aim of this study was to report the clinical features, reliability, and various applications of free anterolateral thigh (ALT) flaps and to provide a 10-year retrospective review of the application of this flap in head and neck tumour patients. A retrospective study was performed of 872 patients who underwent immediate reconstruction of head and neck tumour-induced defects with ALT flaps between April 2005 and April 2014. The study sample consisted of 609 males and 263 females aged 18-79 years. The shapes and sizes of the flaps were designed individually to meet various demands of reconstruction in the head and neck region. The overall rate of successful reconstruction was 97.4%. The reasons for 57 cases of flap compromise were analyzed. The time to detection of flap crisis was often within the first 8h after surgery (64.9%). One- and two-vein anastomosis strategies in microsurgery were compared, and significant differences were observed in terms of the time to detection of flap compromise and the rate of successful flap salvage. In conclusion, the free ALT flap provides unique features for the reconstruction of oral and facial defects in a reliable and versatile approach. The ALT flap is a favourable and versatile 'workhorse' flap for head and neck reconstruction.

National rates of Helicobacter pylori recurrence are significantly and inversely correlated with human development index.

BACKGROUND: Helicobacter pylori infection is a worldwide threat to human health with recurrence rates that vary widely. The precise correlation between H. pylori recurrence and socioeconomic development has not been determined. AIM: To determine H. pylori recurrence rates after successful eradication and their association with socioeconomic development metrics. METHODS: Bibliographical searches were performed in the MEDLINE database. We reviewed all results, filtered by inclusion criteria, extracted primary results to calculate H. pylori recurrence rates and calculated national Human Development Index (HDI) values for the periods during which the studies were conducted. RESULTS: One thousand two hundred and twenty six cases of H. pylori recurrence in 77 eligible studies were observed in 43 525.1 follow-up patient-years after successful eradication therapy, giving a recurrence rate of 2.82 ± 1.16% per patient-year (weighted mean ± 95% confidence interval). H. pylori recurrence rate was inversely correlated with national HDI on linear (r = -0.633) and weighted least square (r = -0.546) regression analysis. Countries with very high HDI had a mean recurrence rate significantly lower than that of high, medium and low HDI countries (P < 0.01, 0.001, and 0.001, respectively). CONCLUSIONS: Less-developed areas, as measured by HDI, are more likely to have high H. pylori recurrence rates. A different approach to follow-up after H. pylori eradication is needed in developing countries where reinfection is highly prevalent, paying special attention to sources of reinfection and high-risk groups.