Vibrio parahaemolyticus, the main pathogen causing seafood related food poisoning worldwide, has strong biofilm formation ability. ToxR is a membrane binding regulatory protein, which has regulatory effect on biofilm formation of V. parahaemolyticus, but the specific mechanism has not been reported. c-di-GMP is an important second messenger in bacteria and is involved in regulating a variety of bacterial behaviors including biofilm formation. In this study, we investigated the regulation of ToxR on c-di-GMP metabolism in V. parahaemolyticus. Intracellular c-di-GMP in the wild type (WT) and toxR mutant (ΔtoxR) strains were extracted by ultrasonication, and the concentrations of c-di-GMP were then determined by enzyme linked immunosorbent assay (ELISA). Three c-di-GMP metabolism-related genes scrA, scrG and vpa0198 were selected as the target genes. Quantitative real-time PCR (q-PCR) was employed to calculate the transcriptional variation of each target gene between WT and ΔtoxR strains. The regulatory DNA region of each target gene was cloned into the pHR309 plasmid harboring a promoterless lacZ gene. The recombinant plasmid was subsequently transferred into WT and ΔtoxR strains to detect the β-galactosidase activity in the cellular extracts. The recombinant lacZ plasmid containing each of the target gene was also transferred into E. coli 100λpir strain harboring the pBAD33 plasmid or the recombinant pBAD33-toxR to test whether ToxR could regulate the expression of the target gene in a heterologous host. The regulatory DNA region of each target gene was amplified by PCR, and the over-expressed His-ToxR was purified. The electrophoretic mobility shift assay (EMSA) was applied to verify whether His-ToxR directly bound to the target promoter region. ELISA results showed that the intracellular c-di-GMP level significantly enhanced in ΔtoxR strain relative to that in WT strain, suggesting that ToxR inhibited the production of c-di-GMP in V. parahaemolyticus. qPCR results showed that the mRNA levels of scrA, scrG and vpa0198 significantly increased in ΔtoxR strain relative to those in WT strain, suggesting that ToxR repressed the transcription of scrA, scrG and vpa0198. lacZ fusion assay showed that ToxR was able to repress the promoter activities of scrA, scrG and vpa0198 in both V. parahaemolyticus and E. coli 100λpir. EMSA results showed that His-ToxR was able to bind to the regulatory DNA regions of scrA and scrG, but not to the regulatory DNA region of vpa0198. In conclusion, ToxR inhibited the production of c-di-GMP in V. parahaemolyticus via directly regulating the transcription of enzyme genes associated with c-di-GMP metabolism, which would be beneficial for V. parahaemolyticus to precisely control bacterial behaviors including biofilm formation.
Vibrio parahaemolyticus/metabolism* ; Escherichia coli/metabolism* ; Bacterial Proteins/metabolism* ; Transcription Factors/genetics* ; Gene Expression Regulation, Bacterial

Background Imidacloprid is a neonicotinoid insecticide that is widely used in agricultural production, with a high detection rate in human biological samples. Previous studies have shown a high correlation between imidacloprid exposure and liver injury, but the specific mechanism is still unknown. Objective To observe potential toxic effects of HepG2 cells and its perturbation of non-targeted metabolic profile after imidacloprid exposure, and to explore possible molecular mechanisms of hepatotoxicity of imidacloprid by analyzing invovlved biological processes and signaling pathways. Methods HepG2 cell suspension was prepared and seeded in a 96-well plate, which was divided into blank control group, dimethyl sulfoxide (DMSO) solvent control group and imidacloprid exposure groups with multiple concentrations. Each group was set with 5 parallel samples. The viability of HepG2 cells viability were determined after 8 h of exposure to different concentrationsof imidacloprid (1, 2.5, 5, 7.5, 10 mmol·L⁻¹), and the dose-effect relationship was analyzed. A proper concentration (3 mmol·L⁻¹ with 80% viability) was chosen for imidacloprid exposure, non-targeted metabolomic analysis was applied to the cultivated HepG2 cells using UHPLC-Q-TOF/MS technology, the differential metabolites between groups were screened, and the bioprocess and related signaling pathways of their enrichment were annotated using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Results Compared to the other two groups, the survival rates of HepG2 cells in the imidacloprid exposure groups decreased. A survival rate of about 86% of HepG2 cells was found in HepG2 cells exposed to 2.5 mmol·L⁻¹ imidacloprid exposure. The non-targeted metabolomics studies showed that 61 metabolites were significantly affected in HepG2 cells after 3 mmol·L⁻¹ imidacloprid exposure, including creatine (variable importance in projection VIP=1.11, P<0.001), arginine (VIP=1.47, P=0.048), taurine (VIP=4.28, P=0.001), and α-D-glucose (VIP=1.90, P=0.006). The differential metabolites enriched in bioprocess and related signaling pathways were mainly directed to mTOR signaling pathways (P<0.001), arginine and proline metabolism (P=0.002), and galactose metabolism (P=0.015). Conclusion Imidacloprid exposure can significantly inhibit the survival rate of HepG2 cells, and interfere with the mTOR signaling pathway, arginine and proline metabolism, galactose metabolism, and so on.

Humans ; Gastrointestinal Microbiome ; Diabetes Mellitus, Type 2/complications* ; Cholelithiasis

Background In the process of greenhouse working, labor intensity is high and repetitive work involves multiple body parts such as limbs, neck, upper back, and lower back. The prevalence and comorbidity of work-related musculoskeletal disorders (WMSDs) in greenhouse workers are worthy of attention. Objective This study is conducted to investigate the prevalence and comorbidity, as well as potential influencing factors of WMSDs in greenhouse workers. Methods A total of 722 greenhouse workers were selected as the subjects for a cross-sectional epidemiological survey. Through questionnaire survey and physical examination, basic information of the subjects and the prevalence of WMSDs were collected. The participants were divided into low, medium, and high cumulative exposure groups by cumulative exposure index matrix. Chi-square test was used to analyze the difference of prevalence among different cumulative exposure levels, the correlation between the prevalence of WMSDs in paired sites was calculated as prevalence ratio (PR) by using the log-binomial model, the prevalence of multi-site WMSDs in each group was compared by Wilcoxon rank sum test, and the influencing factors of multi-site WMSDs were evaluated by multi-classification logistic regression model. Results The prevalence rate of WMSDs in the greenhouse workers was 78.7% (568/722). The main affected sites of body were lower back, legs, neck, and shoulders, and associated prevalence rates were 47.6%, 46.0%, 27.1%, and 23.8%, respectively. By constructing a cumulative exposure index matrix, the low, medium, and high cumulative exposure groups contained 121, 196, and 405 workers respectively. The prevalence rates of WMSDs in lower back, legs, or shoulders were significantly different among groups with different exposure levels (P<0.05), and the prevalence rates increased with higher cumulative exposure levels (lower back, \begin{document}${χ} _{{{\rm{trend}}}} ^2$\end{document}=11.144, P<0.05; legs, \begin{document}${χ} _{{{\rm{trend}}}} ^2$\end{document}=6.767, P<0.05; shoulders, \begin{document}${χ} _{{{\rm{trend}}}} ^2$\end{document}=15.666, P<0.05). The results of log-binomial model found that lower back and legs (PR values were 1.57 and 1.43, respectively) as well as neck and shoulders (PR values were 2.00 and 2.07, respectively) among the main affected parts have a strong association with comorbidities. The prevalence of multi-site WMSDs showed that 50.4% of the workers had comorbidity of two or more sites of WMSDs. The results of multi-classification logistic regression analysis indicated that the influencing factors of WMSDs in two sites involved high-level cumulative exposure (OR=2.41, 95%CI: 1.34-4.33) and female (OR=3.27, 95%CI: 2.07-5.16); the influencing factors of WMSDs in three or more sites also included medium-level cumulative exposure (OR=3.78, 95%CI: 1.70-8.39), high-level cumulative exposure (OR=7.34, 95%CI: 3.41-15.80), and female (OR=5.66, 95%CI: 3.48-9.22). Conclusion In this study, the prevalence rates of WMSDs in lower back, legs, neck, and shoulders are high among selected solar greenhouse workers, and WMSDs comorbidity of lower back-legs and neck-shoulders are identified. Greenhouse workers with high cumulative exposure level and female workers report more WMSDs comorbidities in two or more sites.

Background Due to long working time and complex and changeable lighting conditions, greenhouse workers' anisometropia is an issue of concern. Objective This study is conducted to evaluate the relationship between solar greenhouse working and anisometropia of workers. Methods Subjects of a solar greenhouse group and a non-greenhouse group in northwest area of China were selected. Questionnaire survey was used to collect general demographicinformation. Standard Logarithmic Visual Acuity Chart (GB 11533—2011) was used to measure naked eye vision before working, the absolute value of binocular visual acuity difference was calculated and converted into classification variables, and both anisometropia absolute value and classification variables of anisometropia were used as indicators to compare the difference of the two groups. A cumulative exposure index that multiplies exposure time and number of greenhouses was further introduced to evaluate cumulative exposure levels of the greenhouse workers and was used to divide them into low, medium, and high cumulative exposure subgroups. Generalized linear model and logistic regression model were used to analyze possible risk factors associated with anisometropia. Results A total of 1002 subjects were enrolled in this study, including 739 workers in the greenhouse group and 263 workers in the non-greenhouse group. The medians (interquartile intervals) of anisometropia of the greenhouse group and non-greenhouse group were 0.1 (0, 0.2) and 0 (0, 0.1) respectively, and the difference was statistically significant (P<0.05). The proportions of anisometropia=0, ≤0.2, and >0.2 in the greenhouse group were 34.2%, 55.2%, and 10.6%, respectively, and those in the non-greenhouse group were 58.2%, 34.6%, and 7.2%, respectively. The difference of anisometropia distribution between the two groups was statistically significant (P<0.05). According to the cumulative exposure index, the greenhouse group was divided into low, medium, and high cumulative exposure subgroups, with 154 (21.0%), 188 (25.6%), and 392 (53.4%) workers, respectively. There was no statistical significance in anisometropia among workers with different cumulative exposure levels (P>0.05). The results of multiple generalized linear analysis showed that greenhouse working was a risk factor of anisometropia (b=0.053, P<0.05), and the results of multiple logistic regression analysis showed that greenhouse working was associated with an increased risk of anisometropia (OR=2.586, 95%CI: 1.473-4.539). The results of multiple generalized linear analysis showed that medium exposure level increased the degree of anisometropia after adjusting age, gender, and other factors (b=0.054, P<0.05). Conclusion Solar greenhouse working may be a risk factor for increasing anisometropia in workers.

Background As a new type of vegetable production method, solar greenhouse has been widely promoted nationwide. The influence of solar greenhouse working on blood lipid cannot be ignored. Objective The aim of the study is to explore the relationship between solar greenhouse working and blood lipid and family clustering. Methods A total of 744 solar greenhouse workers in northwestern China were selected as the greenhouse group, and 231 general open field farmers in the same area were selected as the non-greenhouse group. The levels of serum total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDLC), and low-density lipoprotein cholesterol (LDLC) in the two groups were detected. Dyslipidemia was determined by a two-classification criteria in the national guideline of 2007. Multiple logistic regression model and multilevel multiple linear regression model were used to explore the relationship of blood lipid with solar greenhouse working, and its family clustering. Results The number of dyslipidemia cases in the greenhouse group and non-greenhouse group was 142 (19.1%) and 43 (18.6%), respectively, and the difference was not statistically significant (P>0.05). The results of multiple logistic regression analysis showed that increasing age (OR=1.019, 95% CI: 1.001-1.038) and increased BMI (OR=1.162, 95% CI: 1.106-1.220) were related to elevated risk of dyslipidemia (all Ps<0.05). The results of multilevel multiple linear regression model showed that the changes of TC, HDLC, and TG/HDLC had family clustering (b=0.238, 95%CI: 0.132-0.430; b=0.044, 95%CI: 0.033-0.065; b=1.003, 95%CI: 0.947-1.059) (all Ps<0.05). Conclusion Solar greenhouse working does not significantly increase the incidence of dyslipidemia, but the levels of TC, HDLC, and TG/HDLC levels in the solar greenhouse workers have family clusters.

Background The aging of the labor force has become a global trend, and various occupational activities can affect blood biochemical indexes and increase the risk of metabolic diseases. Elderly workers are the main laborers in the solar greenhouse industry, and their blood biochemical indexes need more attention. Objective The purpose of this study is to explore the alternation of selected blood biochemical indexes and provide clues for conducting management programs of metabolic diseases in the elderly solar greenhouse workers. Methods The research subjects of the greenhouse group and the non-greenhouse group were selected from a vegetable production base in Northwest China. The elderly workers were selected from a recruited subjects pool for an earlier project by means of matching and non-matching respectively. The matching conditions were gender (consistent), age (±2 years old), body mass index (BMI) (±1 kg·m⁻²), education level (±1 level), smoking (consistent), and drinking (consistent). Routine clinical tests were used to detect serum total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC), fasting blood glucose (GLU), and albumin (ALB), and single-factor and multi-factor analyse were used to identify different indexes in matching and non-matching samples, respectively. The matching and the non-matching samples included 80 pairs of subjects and 327 subjects, respectively. Results In the matching sample set, the greenhouse group's HDLC [(1.61±0.34) mmol·L⁻¹] was lower than the non-greenhouse group's [(2.09±0.37) mmol·L⁻¹] (P<0.05), the level of TG/HDLC in the greenhouse group was (1.17±0.74), higher than that in the non-greenhouse group (0.78±0.47) (P<0.05), and the level of LDLC/HDLC in the greenhouse group was (1.87±0.36), also higher than that in the non-greenhouse group(P<0.05), while there was no statistical difference of the other indexes between the two groups (all Ps>0.05). In the non-matching sample set, the results of multiple linear regression analysis showed that solar greenhouse working correlated with decreased HDLC, and increased TG/HDLC and LDLC/HDLC among the elderly workers (all Ps<0.05). Conclusion Solar greenhouse working may correlate with variations of selected blood biochemical indexes in elderly workers, and the occupational health surveillance of elderly workers should be strengthened.