Background Arsenic, cobalt, barium, and other individual metal exposure have been confirmed to be associated with the incidence of kidney stones. However, there are few studies on the association between mixed metal exposure and kidney stones, especially in occupational groups. Objective To investigate the association between mixed metal exposure and kidney stones in an occupational population from a metal smelting plant. Methods A questionnaire survey was conducted to collect sociodemographic characteristics, medical history, and lifestyle information of 1158 mixed metal-exposed workers in a metal smelting plant in Guangdong Province from July 2021 to January 2022. Midstream morning urine samples were collected from the workers, the concentrations of 18 metals including lithium, vanadium, chromium, manganese, cobalt, nickel, copper, zinc, arsenic, selenium, strontium, molybdenum, cadmium, cesium, barium, tungsten, titanium, and lead were measured by inductively coupled plasma mass spectrometry, and the urinary mercury levels were measured by cold atomic absorption spectroscopy. Based on predetermined inclusion criteria, a total of 919 mixed metal-exposed workers were included in the study, including 117 workers in the kidney stone group and 802 workers in the non-kidney stone group. With a detection rate of urinary metals greater than 80% as entry criterion, 16 eligible metals were finally included for further analysis. Parametric or non-parametric methods were used to compare the differences between continuous or categorical variables of the non-kidney stone group and the kidney stone group. Logistic regression models were constructed to explore the association between individual metal exposures and kidney stones. Weighted quantile sum (WQS) regression models were used to evaluate the association between mixed metal exposure and kidney stones, as well as the weights of each metal on kidney stones. Then Bayesian kernel machine regression (BKMR) models were used to explore the overall effect of mixed metal exposure on renal calculi and the potential interactions between metals. Results We found that there were significant differences in sex, age, length of service, and body mass Index (BMI) between the non-kidney stone group and the kidney stone group (P<0.05). The urinary concentrations of molybdenum and barium in the kidney stone group were higher than those in the non-kidney stone group, and the differences were statistically significant (P<0.05). The logistic regression models demonstrated that urinary cobalt, arsenic, molybdenum, and barium were positively correlated with the risk of kidney stones (P_trend<0.05). The WQS regression models showed that the mixed exposure to vanadium, cobalt, arsenic, molybdenum, and barium was positively associated with the risk of kidney stones (P<0.05). Among them, molybdenum, arsenic, and barium accounted for 0.391, 0.337, and 0.154, respectively. The BKMR results revealed a positive association between metal mixture exposure and the risk of kidney stones (P<0.05). When other metals were fixed at the 25th, 50th, or 75th percentile, arsenic, molybdenum, cobalt, and barium exhibited significant positive effects on the risk of kidney stones (P<0.05), while vanadium showed a significant negative effect (P<0.05). The interaction analysis demonstrated interactions between barium and cobalt, as well as between vanadium and cobalt (P<0.05). Conclusion In the occupational population of this smelter, occupational mixed metal exposure could increase the risk of kidney stones, and the main metals are molybdenum, arsenic, barium, and cobalt.

Objective To investigate the effect of spleen on hepatic macrophages mediated activation of hepatic stellate cells(HSCs)in mice with liver fibrosis.Methods Eighteen male C57BL/6 mice were randomly divided into three groups.Mice in Group A and Group B were injected intraperitoneally with CCl4 to establish liver fibrosis mouse model,while those in Group C were injected with corn oil as normal control.Four weeks later,mice with liver fibrosis received splenectomy(Spx)or sham operation(Sham),respectively.After continuous injection for 2 weeks,liver homogenates(L-Homo)were prepared and liver cells were isolated from the three groups.Expressions of IL-1β,IL-13,TGF-β,TNF-α,PDGF-β and VEGF in the liver homogenates of the three groups were detected by Luminex multifactor analysis.The expressions of these cytokines in liver macrophages(L-Mψ)and other non-parenchymal cells of Sham and Spx mice were analyzed by Real-time quantitative PCR(RT-qPCR)and flow cytometry.Macrophage cell line RAW264.7 or bone marrow-derived macrophages(BMDMs)were treated with liver homogenates from the Sham and Spx groups.Then the differently treated RAW264.7 cells were analyzed for mRNA expressions of cytokines and glutamine metabolism-related molecules by RT-qPCR,or transwell co-cultured with hepatic stellate cell line JS1.After co-culture,the survival and extracellular matrix expression of JS1 cells were analyzed.For comparison,Student's t test(between two groups)or one-way analysis of variance(among multiple groups)were used.Results Compared with normal control group,the concentrations of IL-1β,IL-13,TGF-β and TNF-α in the L-Homo of model group were significantly increased and showed higher levels in Sham group than in Spx group.Moreover,the hepatic macrophages were indicated as the major source of these cytokines.Consistently,macrophages treated with liver homogenate of Sham mice had increased expressions of IL-1β,TGF-β and TNF-α and glutaminase(GLS).After co-culture with macrophages treated with liver homogenate of Sham group rather than Spx group,JS1 expressed higher expressions of α-SMA and collagens.Conclusion The spleen is involved in regulating the secretion of cytokines by hepatic macrophages and enhancing their ability to activate hepatic stellate cells.

Objective To address the quality problems caused by high porosity in the preparation of dental cobalt-chrome alloy prosthetics based on selective laser melting(SLM)technology,we investigated the influence mechanism of different forming process parameters on the microstructure and properties of the materials.Moreover,the range of form-ing process parameters that can effectively reduce defects was precisely defined.Methods The effects of laser power,scanning speed,and scanning distance on the pore properties,surface roughness,and hardness of dental cobalt-chrome al-loy were investigated by adjusting the printing parame-ters in the process of SLM.Through metallographic anal-ysis,image analysis,and molten pool simulation,the pore formation mechanism was revealed,and the relation-ship between the porosity and energy density of SLM dental cobalt-chrome alloy was elucidated.Results When the linear energy density was higher than 0.18 J/mm,the po-rosity defect easily appeared at the bottom of the molten pool.When the laser energy density was lower than 0.13 J/mm,defects occurred in the gap of the molten pool due to insufficient melting of powder.In particular,when the linear energy density exceeded the threshold of 0.30 J/mm or was below 0.12 J/mm,the porosity increased significantly to more than 1%.In addition,we observed a negative correlation between free surface roughness and energy density and an inverse re-lationship between macroscopic hardness and porosity.Conclusion On the basis of the conditions of raw materials and molding equipment used in this study,the key process parameters of SLM of molding parts with porosity lower than 1%were successfully determined.Specifically,these key parameters included the line energy density,which ranged from 0.13 J/mm to 0.30 J/mm,and the scan spacing should be strictly controlled below 90 μm.

Objective:To predict and analyze the T/B combined epitope of EM10 protein in Echinococcus multilocularis, and identify the expressed products of the biosynthetic EM10 multi epitopes. Methods:The gene-related information of EM10 protein was obtained through NCBI GenBank public database. Bioinformatics technique was used to predict and analyze the T/B binding epitopes of EM10 protein. The prokaryotic expession recombinant plasmid pET30a-EM10 (epitope) was synthesized, and transformed into host bacteria Ecoli. BL21 (DE3). The expression of EM10 recombinant multi-epitope protein was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting after induced expression by isopropyl thiogalactopyranoside (IPTG). Results:The total length of EM10 gene was 1 759 bp (GenBank registration number: U05573), and its protein amino acid sequence (GenBank registration number: AAA50580.1) was 559 amino acids. By using Phyre software for homology modeling, the tertiary structure of EM10 protein was obtained, and the T/B combined epitope of EM10 protein was successfully predicted, the dominant epitope was located at 46 - 61, 133 - 183, 239 - 255 and 442 - 475 amino acid sites. The (GGGGS)n linker sequence was used to connect the epitopes to form an EM10 recombinant multi-epitope protein with a total of 206 amino acid. The size of the DNA fragment was 618 bp and the relative molecular weight of the protein was 22.66 × 10 3. The prokaryotic expession recombinant plasmid was validated by enzyme digestion, the results showed that the plasmid size was between 5 000 and 6 000 bp, which was consistent with the length of the constructed plasmid (5 854 bp). SDS-PAGE showed that the target protein was expressed in the supernatant induced by IPTG at 37 ℃ and the effect was the best. The relative molecular weight of the protein was 22.66 × 10 3 by Western blotting, which was consistent with the constructed plasmid. Conclusions:The combined epitope of EM10 T/B is successfully designed and predicted using bioinformatics technology. A prokaryotic expression recombinant plasmid is constructed, the expression of EM10 recombinant multi-epitope protein is verified through experiments, providing an experimental basis for the construction of an EM10 dominant epitope diagnostic kit.

In order to develop a positive quality control products for the detection of porcine repro-ductive and respiratory syndrome virus(PRRSV)nucleic acid by real-time fluorescent quantitative PCR(RT-qPCR),the positive quality control products of PRRSV-1 and PRRSV-2 M genes were prepared using armored RNA technology of MS2 phage.PRRSV-1 and PRRSV-2 M genes were amplified,purified and recovered,and ligated into pET28b vector containing MS2 mature enzyme protein gene and capsid protein.After transformed into BL21(DE3),the gene products were in-duced by IPTG and purified by PEG6000 precipitation method to prepare the armored RNA virus-like particles(AR-PRRSV)containing PRRSV M gene.Following the performance evaluation,as the positive quality control products of PRRSV-1 and PRRSV-2 M genes,AR-PRRSV1M and AR-PRRSV2M were calculated using YY/T 1652-2019 standard.Results showed that it had a good u-niformity,stable storage for the armored virus-like particles at-20,4,25 ℃ for 60 d,and 37 ℃ for 30 d.The prepared armored virus-like particles AR-PRRSV1M and AR-PRRSV2M were deter-mined by digital quantitative PCR(ddPCR)after preliminary quantification by RT-qPCR.The 104 copies/μL of AR-PRRSV1M and AR-PRRSV2M ddPCR fixation was(1.33+0.50)× 104 cop-ies/μL.The above results indicates that the AR-PRRSVM can be used as the quality control of the whole detection process(nucleic acid extraction,reverse transcription and RT-qPCR).

In response to the challenges of small scale and huge labor cost in biomedical feature modeling in current skin disease assisted diagnosis,as well as the inability to accurately describe the time series of patient disease features,a fusion text classification algorithm is used to integrate commonly used text classification models(TextLSTM,TextCNN,and RCNN)to obtain a model based on transfer learning and neural networks(TLNN model).By extracting the medical features of image sensors and quantizing them,the pretreatment reduces the number of foci and eliminates the feature information with large deviations,thus improving the accuracy of decision data.TLNN model achieves an accuracy of 72.36%on ISIC2018 and PH2 datasets,which is higher than those of the other 3 text classification models.The diagnostic accuracy of TLNN model is close to doctor's diagnosis(92%vs 94%),but the effective diagnostic efficiency is significantly higher than doctor's diagnosis(1.17 min/case vs 4.57 min/case),and the overall efficiency is improved by 290%.The results demonstrate that the fusion text classification algorithm model can obtain accurate diagnosis in less time than the traditional manual diagnosis.TLNN model can be applied to disease diagnosis,and assist doctors in medical decision-making,thereby providing patients with high-quality and convenient intelligent diagnosis and treatment services.

Objective:To explore surgical strategies for acute type A aortic dissection involving severe stenosis or occlusion of the carotid arteries.Methods:From January 2019 to March 2023, a total of 29 patients with acute type A aortic dissection involving severe stenosis or occlusion of the carotid arteries were included in the study. All patients underwent emergency surgery, with simultaneous intraoperative neck incision and replacement of the unilateral or bilateral carotid arteries. Among them, there were 19 males with a mean age of(49.57±2.14)years old. Preoperative brain CT indicated abnormalities in 15 cases, transient neurological dysfunction occurred in 5 cases, and syncope in 1 case.Results:Procedures included ascending aorta replacement in 10 cases, Bentall procedure in 18 cases, and Wheat procedure in 1 case. Arch operations involved partial arch replacement in 3 cases and Sun’s procedure in 26 cases. Simple left carotid artery replacement was performed in 6 cases, simple right carotid artery replacement in 19 cases, and bilateral carotid artery replacement in 4 cases. Cerebral protection measures during circulatory arrest included unilateral cerebral perfusion in 24 cases and bilateral cerebral perfusion in 5 cases. The mean operation time was(7. 6±0. 3) h, with a mean cardiopulmonary bypass time of(196. 3±8. 7) min, aortic cross-clamp time of(113.2±6.4) min, ischemic time 12(5-16.5) min, and lowest temperature of(26.3±0.4)°C. One patient experienced in-hospital mortality. Postoperatively, new neurological dysfunction occurred in 2 cases, including 1 case with coma and permanent neurological deficit.Conclusion:In patients with acute type A aortic dissection involving severe stenosis or occlusion of the carotid arteries, simultaneous carotid artery replacement via neck incision during aortic surgery is a safe and reliable surgical approach.

Mycoplasma capricolum subsp. capripneumoniae (Mccp) is the cause of contagious caprine pleuropneumonia (CCPP) in goats. Inactivated vaccines and capsular polysaccharide (CPS) indirect hemagglutination reagents are available for prevention and serological detection, but high culture costs and complex antigen quantification have been plagued by production staff. In order to solve these problems in production practice, a sugar fermentation medium with an initial pH value of 7.8, which could improve the production of two antigens simultaneously, was screened out by changing the initial pH value based on previous Mccp metabolomics analysis. Since phenol red can be identified by UV absorption spectrum and cetyltrimethylammonium bromide (CTAB) can bind to anionic capsular polysaccharide, a UV spectrum measurement method for analyzing the culture stage reached by Mccp and a CTAB precipitation test for relative quantification of capsular polysaccharide antigen content in the fermentation broth were established. The UV spectrum observation method can guide the production of Mccp according to the growth curve of Mccp, which greatly reduces the monitoring time of the traditional CCU method and improves the accuracy of the original eye-observation method. The established CTAB precipitation test can complete the monitoring of CPS content within 5 hours, which greatly reduces the time required compared with the traditional differential technique, and its accuracy was verified by the phenol-sulfuric acid method. The optimized culture medium and the two correlation comparison methods established in this study can effectively reduce the production cost of Mccp and improve the production efficiency. The two assays have been used in the research at our laboratory, which provides experimental data for further improvement of the production process of CCPP inactivated vaccine and capsular polysaccharide as well as rapid quantification.
Humans ; Animals ; Goats ; Cetrimonium ; Mycoplasma ; Polysaccharides

Background Occupational exposure to lead, cadmium, or arsenic is a potential risk factor for blood pressure elevation. Current studies mainly focus on the relationship between a single metal and blood pressure. However, mixed metal exposure often exists in the actual working environment, and the interactive effects of polymetallic interactions on blood pressure and the dose-effect relationship remain unclear yet. Objective To explore the influence proportion of occupational exposure to lead, cadmium, or arsenic on blood pressure and their interactive effects. Methods From January to December 2021, workers from a smelter in southern China were selected. Demographic characteristics, height, weight, and blood pressure of workers were collected through questionnaire and physical examination. At the same time, their urine samples were collected and the levels of urinary lead, urinary cadmium, and urinary arsenic were detected by inductively coupled plasma mass spectrometry, and corrected by urinary creatinine (Cr). Linear regression and logistic regression were used to analyze the relationship between urinary lead, cadmium, and arsenic and blood pressure. Weighted quantile sum (WQS) regression was applied to evaluate the dose-effect relationship between urinary lead, cadmium, and arsenic exposures and blood pressure and the effect weight of each metal on blood pressure. Generalized linear regression and additive/multiplicative scaling were used to identify interactive effects of the three metals on blood pressure. Results A total of 1075 workers were included in this study, with a mean age of (44.68±5.11) years and mean working seniority of (24.66±5.23) years. There were 891 males (88.9%) and 184 were females (17.1%); 24.7% workers were drinkers and 45.7% workers were smokers; 302 workers (28.1%) reported hypertension and 37 of them were taking antihypertensive drugs. The P₅₀ (P₂₅, P₇₅) levels of urinary lead, urinary cadmium, and urinary arsenic were 6.11 (3.71, 11.08), 3.88 (2.68, 5.44), and 26.04 (19.99, 35.11) μg·g⁻¹, respectively. After adjusting for gender, age, working seniority, body mass index, smoking, drinking, and the usage of antihypertensive drugs, systolic and diastolic blood pressure increased by 0.772 and 0.418 mmHg respectively for 10% increase in lead, cadmium, and arsenic mixed exposure. Urinary cadmium, among the three single exposures, had the greatest effect on systolic and diastolic blood pressure, weight (w)=0.523 and 0.551 respectively. The interaction of urinary lead and urinary cadmium was positively correlated with the occurrence of hypertension, multiplicative interaction OR (OR_int)=1.88 (95%CI: 1.09, 3.63), attributable proportion due to interaction (AP)=1.19 (95%CI: 0.40, 8.18). Conclusion This study shows that mixed exposure to lead, cadmium, and arsenic has a positive relationship with blood pressure, in which cadmium plays a major role. Co-exposure to lead and cadmium has a positive interactive effect on hypertension development and systolic blood pressure elevation.

Objective: To investigate the effect of combined exposure to four heavy metals (lead, cadmium, arsenic, mercury) on early kidney injury in occupational population. Methods: A total of 384 workers exposed to combined heavy metals in a non-ferrous metal smelting plant in Guangdong Province were selected as the research subjects using judgment sampling method. The levels of blood lead, urinary cadmium and urinary arsenic were detacted by inductively coupled plasma mass spectrometry, while urinary mercury levels were measured using cold atomic absorption spectroscopy (acidic tin chloride reduction method). The levels of biomarkers such as urinary β₂-microglobulin (β₂-MG), kidney injury molecule-1 (Kim-1) and neutrophil gelatinase-associated lipocalin (NGAL) were detected by enzyme-linked immunosorbent assay. Spearman correlation analysis, linear regression, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were used to analyze the association between the exposure to the four heavy metals and early kidney injury biomarkers. Results: The median of blood lead, urinary cadmium, urinary arsenic and urinary mercury were 0.47 μmol/L and 4.450, 27.790 and 0.520 μg/gCr, respectively. The median of urinary β₂-MG, Kim-1 and NGAL were 62.960, 1.130 and 18.150 μg/gCr, respectively. Spearman correlation analysis showed that urinary levels of β₂-MG, Kim-1, and NGAL were weakly correlated with blood lead and urinary mercury levels (all P<0.01), but not correlated with urinary cadmium and urinary arsenic (all P>0.05). The results of multiple linear regression analysis showed that urinary mercury was positively correlated with urinary β₂-MG, Kim-1 and NGAL (all P<0.01), urinary arsenic was positively correlated with urinary β₂-MG level (P<0.01), and blood lead was negatively correlated with urinary β₂-MG and Kim-1 (all P<0.05). The WQS regression analysis showed that the combined effect of the four heavy metals was positively correlated with urinary β₂-MG, Kim-1 and NGAL (all P<0.01), with mercury having the highest impact and lead the lowest. BKMR model analysis showed the increasing trend in urinary β₂-MG, Kim-1 and NGAL with the increasing levels of the combined exposure to the four heavy metals. Urinary β₂-MG, Kim-1 and NGAL decreased when urinary mercury level increased from the 25th percentile to the 75th percentile and the other metals were correspondingly fixed at a certain level. When the blood exposure levels of other metals remained at the corresponding median levels, urinary β₂-MG, Kim-1 and NGAL levels were positively correlated with urinary arsenic level, but no significant linear dose-response relationship was observed with the other three heavy metals. Conclusion: sLead, arsenic, and mercury are independently associated with early kidney injury biomarkers in occupational population from non-ferrous metal smelting. The four heavy metals had positive combined effects on urinary β₂-MG, Kim-1 and NGAL, with mercury having the greatest impact.