ObjectiveTo investigate the chemical hazards in the production line of lithium batteries, so as to provide a scientific basis for the management of occupational-health risk and to promote the healthy and sustainable development of the lithium battery industry. MethodsAn on-site survey on the process flow of the production of lithium battery was conducted in an enterprise. Volatile organic compounds (VOCs) in the occupational environment were collected by Summa canisters, carbonates and N-methyl pyrrolidone (NMP) were collected using activated carbon tubes, and airborne metals were collected using filter membranes. VOCs, carbonates and NMP were detected by gas chromatography-mass spectrometry (GC-MS), and airborne metal elements in the dust samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). ResultsNon-targeted environmental monitoring results indicated that NMP was detected in the negative /positive electrode coating, assembly and drying filling workstations, dimethyl carbonate (DMC) was detected in the assembly, drying and electrolyte injection workstations, and ethyl methyl carbonate (EMC) was detected solely in the electrolyte injection workstation. Semi-quantitative analyses of VOCs identified 136 pollutants, including acrylonitrile and halohydrocarbons. Quantitative targeted environmental monitoring results revealed the highest geometric mean (GM) concentration of EMC (31.450 mg·m^-3) was found in the assembly and drying workstations, diethyl carbonate (DEC) was detected in all workstations. While vinylene carbonate (VC) and ethylene carbonate (EC) were detected only in electrolyte injection, assembly and drying workstations. NMP was detected in all positive electrode coating samples, with a GM concentration of 5.68 mg·m^-3 (concentration range: 4.0‒ 7.4 mg·m^-³). Lithium was exclusively detected in dust samples from the liquid injection workstation (GM: 0.014 μg·m^-³). ConclusionNMP, EMC, DEC, and other chemicals are identified at the key workstations such as the positive electrode coating, electrolyte injection, assembly and drying in the lithium production line. Furthermore, semi-quantitative VOCs analyses identified 136 pollutants, demonstrating a characteristic of multicomponent chemical exposure.

Objective To establish a gas chromatography-mass spectrometry (GC-MS) method for the simultaneous determination of four carbonate compounds (CCs), including ethyl methyl carbonate (EMC), diethyl carbonate (DEC), vinylene carbonate (VC), and ethylene carbonate (EC) in workplace air. Methods Vapor-phase EMC, DEC, VC, and EC in workplace air were collected using activated carbon tubes. After desorption with dichloromethane, the samples were analyzed by GC-MS. Qualitative identification was performed based on retention times and characteristic ions, while quantitative analysis was conducted using peak areas of selected characteristic ions. Results The quantitative determination ranges for the four CCs were from 0.57×10⁻³ to 200.00 mg/L, with correlation coefficients ≥0.999 45. The detection limit ranged from 0.17 to 1.60 μg/L, and the lower limit of quantification ranged from 0.57 to 5.33 μg/L. The minimum detection concentration and minimum quantitation concentration were 0.11-1.07 and 0.38-3.55 μg/m³, respectively. Mean spiked recoveries ranged from 85.70% to 111.65%. The intra- and inter-batch relative standard deviations were 0.11%-2.04% and 1.27%-5.18%, respectively. Mean desorption efficiencies of the method ranged from 74.70% to 118.20%. EMC, DEC, and EC samples were stable for up to five days at 4 °C, while VC samples were stable for up to three days at 4 °C. Conclusion The GC-MS method is suitable for the simultaneous determination of the four CCs including EMC, DEC, VC, and EC in workplace air.

In order to investigate the role of sRNA OxyS in the pathogenicity of Salmonella typhi-murium infection,the OxyS gene deletion strain ATCC25241 △OxyS and the back-complemented strain ATCC25241 △OxyS/OxyS of Salmonella typhimurium ATCC25241 were constructed by using λRed homologous recombination technique.We investigated the effect of OxyS deletion on the biological characteristics and pathogenicity of Salmonella typhimurium ATCC25241.The re-sults showed that the deletion of OxyS did not affect the growth rate,the ability of biofilm forma-tion,and the ability of adhesion,invasion and intracellular survival of Salmonella typhimurium,but significantly reduced the motility of Salmonella typhimurium as well as its ability to survive in alkaline and oxidative environments.The results of mouse infection test showed that OxyS dele-tion caused a significant decrease in the virulence of Salmonella typhimurium in mice,and toxicity is reduced obviously.The qPCR results also showed that OxyS deletion could lead to changes in the transcript levels of a number of virulence-related genes of Salmonella typhimurium such as pipB,orf245,csgA,invH,tatA,sipA,sipB,and so on.The above results indicate that OxyS gene affects the biological characteristics and pathogenicity of Salmonella typhimurium and is an important virulence regulator of Salmonella typhimurium.

In order to establish a serological method for the detection of bovine respiratory syncytial virus,the prokaryotic expression of four proteins of BRSV,G,F,P,and M was carried out,and the most suitable coating antigen was screened to establish an indirect ELISA detection method.The results showed that the four recombinant proteins of BRSV,rG,rF,rP and rM were successfully expressed.The results of checkerboard screening showed that the P/N value of rG protein was the largest,which was determined to be the best coating antigen established by indirect ELISA meth-od.The optimal reaction conditions for indirect ELISA were as follows:the mass concentration of rG protein coating was 1 mg/L,37℃ for 2 h;3％BSA 37℃ block for 1 h;Serum was diluted 1∶50 and incubated at 37℃ for 1h;Secondary antibody 1∶5 000 dilution,37℃ for 30min;The color development conditions of the substrate were 37℃ for 15 min;Thirty negative sera were selected,and the cut-off value was determined to be 0.63 by the established indirect ELISA method.The re-sults of the specificity test showed that the indirect ELISA method established in this test only recognized BRSV-positive serum,and did not react with IBRV,BCoV,and BPIV3-positive serum.The results of repeatability test showed that the method had good repeatability,and the coefficient of variation within and between batches was less than 10％.The results of the sensitivity test showed that the BRSV-positive serum was still positive when diluted to 1∶8 192.The indirect ELISA method established in this experiment was used to detect 100 clinical serum samples at the same time,and the total coincidence rate of the two reached 90.48％,the positive coincidence rate was 93.42％,and the negative coincidence rate was 82.75％.The indirect ELISA established in this test can be used for the detection of bovine respiratory syncytial virus in clinical practice.

In order to establish a serological method for the detection of bovine respiratory syncytial virus,the prokaryotic expression of four proteins of BRSV,G,F,P,and M was carried out,and the most suitable coating antigen was screened to establish an indirect ELISA detection method.The results showed that the four recombinant proteins of BRSV,rG,rF,rP and rM were successfully expressed.The results of checkerboard screening showed that the P/N value of rG protein was the largest,which was determined to be the best coating antigen established by indirect ELISA meth-od.The optimal reaction conditions for indirect ELISA were as follows:the mass concentration of rG protein coating was 1 mg/L,37℃ for 2 h;3％BSA 37℃ block for 1 h;Serum was diluted 1∶50 and incubated at 37℃ for 1h;Secondary antibody 1∶5 000 dilution,37℃ for 30min;The color development conditions of the substrate were 37℃ for 15 min;Thirty negative sera were selected,and the cut-off value was determined to be 0.63 by the established indirect ELISA method.The re-sults of the specificity test showed that the indirect ELISA method established in this test only recognized BRSV-positive serum,and did not react with IBRV,BCoV,and BPIV3-positive serum.The results of repeatability test showed that the method had good repeatability,and the coefficient of variation within and between batches was less than 10％.The results of the sensitivity test showed that the BRSV-positive serum was still positive when diluted to 1∶8 192.The indirect ELISA method established in this experiment was used to detect 100 clinical serum samples at the same time,and the total coincidence rate of the two reached 90.48％,the positive coincidence rate was 93.42％,and the negative coincidence rate was 82.75％.The indirect ELISA established in this test can be used for the detection of bovine respiratory syncytial virus in clinical practice.

In order to investigate the role of sRNA OxyS in the pathogenicity of Salmonella typhi-murium infection,the OxyS gene deletion strain ATCC25241 △OxyS and the back-complemented strain ATCC25241 △OxyS/OxyS of Salmonella typhimurium ATCC25241 were constructed by using λRed homologous recombination technique.We investigated the effect of OxyS deletion on the biological characteristics and pathogenicity of Salmonella typhimurium ATCC25241.The re-sults showed that the deletion of OxyS did not affect the growth rate,the ability of biofilm forma-tion,and the ability of adhesion,invasion and intracellular survival of Salmonella typhimurium,but significantly reduced the motility of Salmonella typhimurium as well as its ability to survive in alkaline and oxidative environments.The results of mouse infection test showed that OxyS dele-tion caused a significant decrease in the virulence of Salmonella typhimurium in mice,and toxicity is reduced obviously.The qPCR results also showed that OxyS deletion could lead to changes in the transcript levels of a number of virulence-related genes of Salmonella typhimurium such as pipB,orf245,csgA,invH,tatA,sipA,sipB,and so on.The above results indicate that OxyS gene affects the biological characteristics and pathogenicity of Salmonella typhimurium and is an important virulence regulator of Salmonella typhimurium.

Humans ; Occupational Health ; Occupational Health Services

AIM: To explore the effect of bone marrow-derived mesenchymal stem cells (BMSCs) combined with vitamin E on the inflammatory reaction in acute kidney injury ( AKI) rats.METHODS:Gentamicin was used to in-duce AKI and the rats were treated with BMSCs combined with vitamin E.After treatment, the rat plasma and kidney tis-sues were collected, and the expression of inflammatory factors at mRNA and protein levels was detected by real-time quan-titative PCR and ELISA.RESULTS:After the treatment with BMSCs combined with vitamin E, the inflammatory proteins were down-regulated in the plasma and the renal tissues.Compared with single treatment group, the decreases in the in-flammatory proteins were more obvious in combined treatment group.CONCLUSION: The method of BMSCs combined with vitamin E takes the anti-inflammatory effect on AKI, indicating a new and potential mode in clinical application for AKI therapy.

Objective To investigate physical development status on soldiers of Chinese people's armed tactical unit, as to provide basic data for selection of soldiers and health evaluation. Methods To measure the height, weight, chest cir-cumference for soldiers of Chinese people's armed tactical unit, to calculate the development index and then to com-pare and analyse Accordingly. Results (1)The height, weight, chest circumference, Index of weight, Index of chest cir-cumference and index of Vervaeck were significantly higher than that of local college students, and had significant dif-ferences (P<0.01). (2)The southern and northern soldiers in three indicators of height, weight, chest circumference were higher than GJB, and they all had significant differences (P<0.01). The height evaluation of northern soldiers was supe-rior to southern.The body symmetry degrees on soldiers of north and south had no significant difference (P > 0.05). Conclusion The physical development state of this armed police tactical unit soldiers were better than that of local col-lege students, achieved and exceeded the GJB, the height of northern soldiers were high than southern. The body sym-metry degrees on soldiers of north and south were all good. The excellent percent and better percent for Comprehensive evaluation of physical development were higher.

ObjectiveTo access the value of combined application of high-resolution interstitial MR lymphangiography (MRL) and heavily T2WI for the visualization of lymphatic vessels in patients with primary lymphedema.Methods Forty lower extremities in 31 patients with primary lymphedema were examined by heavily T2 WI and interstitial MRL with a 3.0 T MR unit (Philips Medical Systems,Best,the Netherlands).Two experienced radiologists analyzed the images and tried to determine the differences in number of lymphatic vessels,and their maximum diameters,SNR and CNR,and accumulated lymph fluid in the tissue.Statistical analyses were conducted by using Wilcoxon test and t test.ResultsDilated lymphatic vessels in 73 leg segments of 40 lower extremities were visualized on heavily T2WI (median 5,1 to 24),which were more than those on MRL ( median 3,1 to 16) (Z =-2.92,P ＜ 0.01 ).The maximum diameter of lymphatic vessels was (4.3 ± 1.5 ) mm on heavily T2 WI,whereas it was ( 3.4 ± 1.0) mm on MRL ( t =6.90,P ＜ 0.0 1 ).The average SNR and CNR in the dilated lymphatic vessels were 257 ± 130,207 ± 113 on MRL and 169 ± 91,135 ± 82 on heavily T2 WI,which was statistically significant ( SNR t =- 5.95,CNR t =-5.10; P ＜ 0.01 ).The visualization of regions of accumulated lymph fluid on heavily T2WI (median 1 ) had a higher score than that on MRL ( median 0 ) ( Z =- 5.64,P ＜ 0.01 ).Conclusions The heavily T2WI has greater sensitivity and the MRL image has better SNR and CNR.Combining these two MR techniques can provide adequate information for clinicians in the therapeutic planning of patients with advanced stages of lymphedema.