[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.

[A multi-center retrospective study of perioperative chemotherapy for gastric cancer based on real-world data].

Objective: To explore the effect of perioperative chemotherapy on the prognosis of gastric cancer patients under real-world condition. Methods: A retrospective cohort study was carried out. Real world data of gastric cancer patients receiving perioperative chemotherapy and surgery + adjuvant chemotherapy in 33 domestic hospitals from January 1, 2014 to January 31, 2016 were collected. Inclusion criteria: (1) gastric adenocarcinoma was confirmed by histopathology, and clinical stage was cT2-4aN0-3M0 (AJCC 8th edition); (2) D2 radical gastric cancer surgery was performed; (3) at least one cycle of neoadjuvant chemotherapy (NAC) was completed; (4) at least 4 cycles of adjuvant chemotherapy (AC) [SOX (S-1+oxaliplatin) or CapeOX (capecitabine + oxaliplatin)] were completed. Exclusion criteria: (1) complicated with other malignant tumors; (2) radiotherapy received; (3) patients with incomplete data. The enrolled patients who received neoadjuvant chemotherapy and adjuvant chemotherapy were included in the perioperative chemotherapy group, and those who received only postoperative adjuvant chemotherapy were included in the surgery + adjuvant chemotherapy group. Propensity score matching (PSM) method was used to control selection bias. The primary outcome were overall survival (OS) and progression-free survival (PFS) after PSM. OS was defined as the time from the first neoadjuvant chemotherapy (operation + adjuvant chemotherapy group: from the date of operation) to the last effective follow-up or death. PFS was defined as the time from the first neoadjuvant chemotherapy (operation + adjuvant chemotherapy group: from the date of operation) to the first imaging diagnosis of tumor progression or death. The Kaplan-Meier method was used to estimate the survival rate, and the Cox proportional hazards model was used to evaluate the independent effect of perioperative chemo therapy on OS and PFS. Results: 2 045 cases were included, including 1 293 cases in the surgery+adjuvant chemotherapy group and 752 cases in the perioperative chemotherapy group. After PSM, 492 pairs were included in the analysis. There were no statistically significant differences in gender, age, body mass index, tumor stage before treatment, and tumor location between the two groups (all P>0.05). Compared with the surgery + adjuvant chemotherapy group, patients in the perioperative chemotherapy group had higher proportion of total gastrectomy (χ(2)=40.526, P<0.001), smaller maximum tumor diameter (t=3.969, P<0.001), less number of metastatic lymph nodes (t=1.343, P<0.001), lower ratio of vessel invasion (χ(2)=11.897, P=0.001) and nerve invasion (χ(2)=12.338, P<0.001). In the perioperative chemotherapy group and surgery + adjuvant chemotherapy group, 24 cases (4.9%) and 17 cases (3.4%) developed postoperative complications, respectively, and no significant difference was found between two groups (χ(2)=0.815, P=0.367). The median OS of the perioperative chemotherapy group was longer than that of the surgery + adjuvant chemotherapy group (65 months vs. 45 months, HR: 0.74, 95% CI: 0.62-0.89, P=0.001); the median PFS of the perioperative chemotherapy group was also longer than that of the surgery+adjuvant chemotherapy group (56 months vs. 36 months, HR=0.72, 95% CI:0.61-0.85, P<0.001). The forest plot results of subgroup analysis showed that both men and women could benefit from perioperative chemotherapy (all P<0.05); patients over 45 years of age (P<0.05) and with normal body mass (P<0.01) could benefit significantly; patients with cTNM stage II and III presented a trend of benefit or could benefit significantly (P<0.05); patients with signet ring cell carcinoma benefited little (P>0.05); tumors in the gastric body and gastric antrum benefited more significantly (P<0.05). Conclusion: Perioperative chemotherapy can improve the prognosis of gastric cancer patients.

[Determination of seven urinary metabolites of benzene, toluene and xylene by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry].

Objective: To develop a method using ultra-high performance liquid chromatography-triple quadrupole mass spectrometry to determine the urinary metabolites of benzene, toluene and xylene. The selected metabolites are S-phenylmercapturic acid (S-PMA) , trans, trans-muconic acid (t, t-MA) , 8-hydroxy-2 deoxyguanosine (8-OHdG) , hippuric acid (HA) , 2-methylhippuric acid (2-MHA) , 3-methylhippuric acid (3-MHA) and 4-methylhippuric acid (4-MHA) . Methods: The urine sample was pretreated using methanol to precipitate the proteins. HSS T3 chromatographic column was used to separate the metabolites. The mass spectrometric acquisition was carried out using multiple reaction monitoring (MRM) after ionization with ESI source. External standard method was used for quantification. Results: All the standard curves showed good linear relation, and r of the seven metabolites was all above 0.999. The detection limits and quantitative limits of the seven metabolites were 0.01-500 ng/ml and 0.02-1 000 ng/ml (based on the actual dilution ratio) , respectively. The average spiked recoveries of four loadings ranged from 85.8% to 109.9%. The intra-day and inter-day precisions were 0.2%-4.5% and 0.6%-9.5%, respectively. The samples can be kept for at least 14 days at both 4 ℃ and -20 ℃. Conclusion: This method is simple, rapid and highly sensitive with low cost, and its accuracy, precision and stability can meet the daily test requirements. It can be applied for the determination of urinary S-PMA, t, t-MA, 8-OHdG, HA, 2-MHA, 3-MHA and 4-MHA for the occupational population exposed to benzene, toluene and xylene.

[Determination of Cortisol in Saliva by Liquid Chromatography Tandem Mass Spectrometry].

Objective: To establish a liquid chromatography tandem mass spectrometry method to determine the cortisol in saliva. Methods: Take 0.5 ml saliva sample into a 2 ml centrifuge tube, add excess sodium chloride and 1ml acetonitrile to it, then vortex for 3 min, centrifuge for 10 min at 15 000 r/min, and take 800 µl of the upper layer to another centrifuge tube. Finally, the sample was concentrated by a vacuum concentrator and brought to 200 µl with the initial mobile phase. Then, the sample was analyzed by liquid chromatography tandem mass spectrometry. The target compound was quantified by external standard curve method. Results: The linear range of the method was 0.02-5.00 ng/ml, r=0.999 9, the method limit of the detection was 0.002 ng/ml, the method limit of quantitative was 0.02 ng/ml, and the spiked recoveries were 89.60%-98.60%. The intra-assay precision was 1.90%-3.30%, and the inter-assay precision was 4.20%-9.00%; samples could be stored at -20 °C for at least 14 days. The determination of cortisol could not be interfered by other endogenous substances in the sample. Conclusion: The method is simple in pretreatment, high sensitivity, good reproducibility and good recovery, and it is suitable for the quantitative analysis of cortisol in saliva for normal and occupationally stressed populations.

The relationship between small intestinal bacterial overgrowth and irritable bowel syndrome.

OBJECTIVE: To explore the relationship between small intestinal bacterial overgrowth (SIBO) and irritable bowel syndrome (IBS). PATIENTS AND METHODS: Fifty IBS patients in the hospital from January 2015 to December 2015 were assigned to the treatment group, and 50 healthy persons were assigned to the control group. Lactulose hydrogen and methane breath test were performed to measure the percentage of SIBO and oro-cecal transit time (OCTT) in treatment group and control group. These subjects were further assigned to negative SIBO group and positive SIBO group to analyze the scores of symptoms. RESULTS: The percentage of positive SIBO in the treatment group (72%, 36/50) was significantly higher (p<0.05) than the control group (38%, 19/50). The scores of symptoms on the episode of IBS were not significantly different between the positive SIBO subgroup and the negative SIBO subgroup. The scores of symptoms in breath test were not significantly different between the positive SIBO subgroup and the negative SIBO subgroup. The OCTT in the treatment group (69.34±1.27 min) was significantly lower (p<0.05) than the control group (85.16±1.75 min). The OCTT in the positive SIBO group (88.57±4.62 min) was significantly higher (p<0.05) than the control group (73.42±5.25 min). The results of lactulose hydrogen and methane breath test in the treatment group were positively correlated (r = 0.987, p<0.01). The results of lactulose hydrogen and methane breath test in the control group after oral administration of lactulose were also positively correlated (r = 0.736, p<0.01). CONCLUSIONS: SIBO was related to IBS and could prolong OCTT, yet not worsen IBS.

A Bayesian-based two-stage inexact optimization method for supporting stream water quality management in the Three Gorges Reservoir region.

In this study, a Bayesian-based two-stage inexact optimization (BTIO) method is developed for supporting water quality management through coupling Bayesian analysis with interval two-stage stochastic programming (ITSP). The BTIO method is capable of addressing uncertainties caused by insufficient inputs in water quality model as well as uncertainties expressed as probabilistic distributions and interval numbers. The BTIO method is applied to a real case of water quality management for the Xiangxi River basin in the Three Gorges Reservoir region to seek optimal water quality management schemes under various uncertainties. Interval solutions for production patterns under a range of probabilistic water quality constraints have been generated. Results obtained demonstrate compromises between the system benefit and the system failure risk due to inherent uncertainties that exist in various system components. Moreover, information about pollutant emission is accomplished, which would help managers to adjust production patterns of regional industry and local policies considering interactions of water quality requirement, economic benefit, and industry structure.

Tumor volume as a prognostic factor was superior to the seventh edition of the pT classification in resectable gastric cancer.

PURPOSE: To demonstrate that the seventh edition of the tumor-node-metastasis (TNM) classification for gastric cancer (GC) should be updated with the tumor volume (pTV) for the improvement of its prognostic prediction accuracy. METHODS: A total of 497 stage TNM I-III GC patients who underwent curative gastrectomy between January 2003 and December 2007 in our center were enrolled in this study. pTV equals to (tumor diameter/2)(2) × pT stage. RESULTS: In the step 1 multivariate analysis, depth of invasion (pT) was confirmed to be an independent prognostic factors. However, when pTV was included in the step 2 multivariate analysis, pTV classification became significant, while pT classification disappeared. pT classification was substituted by pTV. For patients in each of the pT, significant differences in survival could always be observed among patients in different pTV classification. For patients in each pTV classification, prognosis was highly homologous between those in different pT classifications. TNM classification and the tumor volume-node-metastasis (TvNM) classification were directly compared for convenience. We found the TvNM classification (HR = 1.687, P < 0.001) was the most appropriately prognostic classification for predicting the OS of gastric cancer patients after curative surgery. CONCLUSIONS: pTV maybe an independent prognostic factor in overall survival in GC, and pTV staging system maybe more reliable than the Union International Center Cancer and American Joint Committee (UICC/AJCC) on cancer pT system for prognostic assessment. pTV should be recommended as an important clinicopathologic variable for enhancement the accuracy of the prognostic prediction of GC patients in clinic.

Cyclooxygenase inhibitors use is associated with reduced risk of esophageal adenocarcinoma in patients with Barrett's esophagus: a meta-analysis.

BACKGROUND: Esophageal adenocarcinoma (EAC) has high mortality and is increasing in incidence. Barrett's esophagus (BE) increases the risk for EAC. Studies have reported inconsistent findings on the association between use of cyclooxygenase (COX) inhibitors and the risk of neoplastic progression in BE patients. Therefore, we performed a meta-analysis to investigate this association. METHODS: A meta-analysis was undertaken among a total of 9 observational studies using fixed- and random-effects models, comprising 5446 participants; 605 had EAC or high-grade dysplasia (HGD). RESULTS: Overall, COX inhibitors use was associated with a reduced risk of EAC/HGD among BE patients (relative risk (RR)=0.64, 95% confidence interval (CI)=0.53-0.77). Aspirin use also reduced the risk of EAC/HGD (RR=0.63, 95% CI=0.43-0.94), as well as non-aspirin COX inhibitors (RR=0.50, 95% CI=0.32-0.78). The chemopreventive effect seemed to be independent of duration response. CONCLUSIONS: Cyclooxygenase inhibitors use is associated with a reduced risk of developing EAC in patients with BE. Both low-dose aspirin and non-aspirin COX inhibitors are associated with a reduced risk of neoplasia. More well-designed randomised controlled trials are needed to increase our understanding of the chemopreventive effect of COX inhibitors.