Objective To compare and analyze the biological effects of two types of helmets,which have different masses and centroids,on the neck of pilots under rapid braking condition,and provide new ideas for improving the ergonomic design of helmets for pilots.Methods A finite element model of the head,neck,helmet,and restraint system was established using Hyper Mesh 14.0 software.Finite element simulation was used to study the neck biological effects of pilots wearing different helmets for rapid braking.Results After wearing Type Ⅰ and Type Ⅱ helmets,the trend,occurrence time,and location of the maximum stress borne by each vertebra and intervertebral disc are basically consistent.The maximum stress on the vertebrae above C3 is smaller when wearing a Type Ⅰ helmet,while the maximum stress on the vertebrae below C3 is smaller when wearing a Type Ⅱ helmet.The maximum stress on the C2～C3 intervertebral disc is relatively small when wearing a TypeⅠhelmet,while the intervertebral discs below it are relatively small when wearing a Type Ⅱ helmet.The ligament elongation rate and maximum neck injury index Nij of wearing Type Ⅰ helmets are both relatively high.Conclusion Type Ⅰ helmet has a significant biological impact on the neck of pilots during rapid braking.

To summarize the problems and improvement suggestions in the implementation of GBZ158, the focus groups interview was used to interview industry experts from CDC, Occupational disease prevention and control hospital institutes, employers, third d dd鄄party technical service institutions and universities, and extract their opinions on the problems and improvement suggestions in the implementation of the standard. The operability of GBZ 158 is not strong, and there is a certain overlap with the signs in the fields of firefighting, safety and other fields. It urgently needs to be modified to comply with the reality of occupational health management in China. There are many and concentrated revision opinions on "6. Notification Cards for Occupational Hazards of Toxic Substance in Workplaces" and "7. Setting of Warning Signs in Workplaces with Toxic Substances". It is concluded that Some technical indicators of GBZ 158 have not been according with the current actual work of occupational health, and need to be revised and improved urgently, which includes enhancing the coordination with standards in the fields of firefighting and safety, supplementing normative reference documents, clarifying the setting conditions, scope of use, and application examples of warning signs of occupational hazards.

Objective:To investigate the impact of chromate exposure on pulmonary function indices in occupational populations and explore the potential role of alterations in inflammatory indicators in this process.Methods:In July 2024, A cross-sectional analysis was conducted using occupational health examination data of 30875 workers from chromate-related enterprises in Jiangsu Province in 2020 and 2021. Based on the occupational positions and whether there is chromium acid salt exposure in the occupational hazards of the research subjects over the years, they are divided into chromium acid salt exposure group and non-exposure group. For those exposed to chromium acid salts, based on job position descriptions and duration of chromium acid salt exposure, they are further categorized into intermittent exposure group and continuous exposure group; among them, the actual exposure time in the intermittent exposure group is less than half of the working shift time, and the exposure duration is less than the total working life. Pulmonary function test indicators include forced vital capacity (forced vital capacity, FVC) %, first-second forced expiratory volume (forced expiratory volume in one second, FEV 1.0) %, and the ratio of first-second forced expiratory volume to forced vital capacity (FEV 1.0/FVC) %. Peripheral blood samples from the upper limbs of the research subjects were collected on an empty stomach for routine blood tests, selecting neutrophil count, platelet count, and lymphocyte count results, calculating the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). Quantitative data that meet normal distribution are expressed using Mean±SD, while variables that do not meet normal distribution are represented by M ( Q1, Q3). Categorical data are expressed using frequency or proportion (%). Linear variable comparisons between groups use t-tests. Generalized linear models were employed to assess the correlation between chromate exposure and pulmonary function indices, while mixed regression models were utilized to explore potential underlying effects. Results:Compared with the non-exposed group, the pulmonary function indices FVC (%), FEV 1.0/FVC (%), and FEV 1.0 (%) in the chromate-exposed group showed a decreasing trend ( P<0.01), indicating statistically significant differences. As the frequency of chromate exposure increased, the prevalence of pulmonary dysfunction rose. The prevalence rates of obstructive, restrictive, and mixed respiratory dysfunction among the chromate-exposed population (including intermittent exposure and continuous exposure groups) were 0.26%, 4.67%, and 0.12%, which were higher than those in the non-exposed group (0.09%, 0.84%, and 0.07%, respectively). All these differences were statistically significant ( P<0.05). After stratification by gender, a negative correlation was observed between chromate exposure and the inflammatory indicator platelet-to-lymphocyte ratio (PLR) ( P<0.05). Potential effect analysis revealed that PLR played a certain mediating role between chromate exposure and the decline in pulmonary function indices, with a mediating proportion of 2.2%. Conclusion:Chromate exposure in occupational populations may lead to a decline in pulmonary ventilatory function and alterations in peripheral blood inflammatory indicators. Inflammatory indicators may be involved in the pulmonary function decline caused by chromate exposure.

Objective:To study and compare the occupational exposure limits (OELs) of nickle and its compounds between China and foreign countries, providing scientific basis for the OEL revision of nickel and its compounds in China.Methods:From July to September 2024, Literature, OEL and related technical documents on nickel and its compounds were searched and sorted systematically at home and abroad, the main contents and technical points of OEL were extracted, and comparative analysis were conducted.Results:The earliest OELs of nickel and its compound introduced to China was maximum allowable concentration (MAC) of nickel carbonyl, and the current effective standard China was occupational exposure limits for hazardous agents in the workplace-part 1: chemical hazardous agents (GBZ 2.1-2019), covering nickel and inorganic compounds and nickel carbonyl. The former was further divided into nickel metal and insoluble compounds, and soluble nickel compounds. Based solely on the OELs of nickel and its compounds, China was relatively lower compared to developed countries such as the United States. There were significant differences in the OEL of different types of nickel and its compounds among different countries, but the OELs in China and the United Kingdom (UK) Health and Safety Executive (HSE) were basically consistent. The European Union, the United States American Conference of Governmental Industrial Hygienists (ACGIH), South Africa etal classified nickel and its compounds into respirable and inhalable based on particle size. GBZ 2.1-2019 in China labeled nickel compounds and nickel carbonyl as G1 (carcinogenic to humans), while ACGIH and National Institute for Occupational Safety and Health (NIOSH) in the United States, HSE in the UK, Australia, South Africa also labeled one or several different types of nickel and its compounds as carcinogenic.Conclusion:Based on the OELs of nickel and its compounds, China is at a relatively loose level. It is suggested to explore the possibility of future revision, considering various adverse health effects. It is suggested to conduct basic research on fibrosis induced by nickel and its compounds, providing scientific basis for revising OELs.

Objective:By systematically evaluate the implementation of GBZ 2.1, so as to provide technical basis for the future revisions of this standard.Methods:From May to October 2023, Based on the pre survey questionnaire, the semi-structured interview method was used to interviews with experts from CDC, Occupational disease prevention and control hospital institutes, employers, occupational hygiene technical service intermediaries and universities, and the inductive method was used to extract the topics and relevant suggestions.Results:Generally, GBZ 2.1 is scientific, practical, progressiveness and operable. There are still some issues such as OELs overlapping and the correspondence between Chinese and English names. The outstanding problem is the coordination with other standard contents.Conclusion:The technical indicators in GBZ 2.1 could adapt to the needs of current practical work. The coordination between standards needs to be clarified, and the new recommended content needs further promotion and exploration on how to implement it.

Objective:To assess the application value of one-hour post-load glucose (1hPG) for detecting prediabetes among individuals with high risk of type 2 diabetes mellitus (T2DM).Methods:The study was conducted between August 2023 and January 2024, and individuals with a high risk of T2DM were invited to receive an oral glucose tolerance test (OGTT), structural questionnaires, physical measurements, and other biochemical examinations. The fasting, one-, and two-hour glucose and insulin were tested. According to the 1hPG cut point on hyperglycemia suggested by International Diabetes Federation (IDF), normal glucose tolerance (NGT) and prediabetes were further divided into two subgroups, respectively, i.e., NGT with 1hPG<8.6 mmol/L (NGT-1hPG-normal), NGT with 1hPG≥8.6 mmol/L (NGT-1hPG-high), prediabetes with 1hPG<8.6 mmol/L (PDM-1hPG-normal), and prediabetes with 1hPG≥8.6 mmol/L (PDM-1hPG-high). The insulin release curve was drawn by the groups as above. Insulin resistance was evaluated by homeostasis model assessment for insulin resistance (HOMA-IR), and β-cell secretory function was evaluated by homeostasis model assessment for β cell function (HOMA-β)/HOMA-IR. Spearman rank correlation analysis was used to calculate the correlation coefficients among 1hPG, 2hPG and HOMA indices, and Steiger′s Z test was used to compare the difference between two correlation coefficients. Receiver operating characteristics (ROC) curves and area under the curve (AUC) were used to assess the accuracy of 1hPG for detecting prediabetes. Results:A total of 2 469 subjects consisting of 1 485 men (60.1%) and 984 (39.9%) women, with a mean age of (45.76±6.20) years, of which 1 844 (74.7%) had 1hPG≥8.6 mmol/L. The prevalence of 1hPG≥8.6 mmol/L was 46.8%, 93.0% and 99.8% in individuals with NGT, prediabetes and newly diagnosed T2DM, respectively ( χ 2=763.78, P<0.001). The insulin release curve showed that insulin secretion increased rapidly in subjects with NGT-1hPG-high, and peaked at one hour, then decreased rapidly, with a significantly higher level of one- and two-hour insulin than those with NGT-1hPG-normal ( P<0.001). Compared to individuals with NGT-1hPG-normal, the counterparts with NGT-1hPG-high exhibited higher HOMA-IR and lower adjusted HOMA-β ( P<0.001). Spearman rank correlation analysis showed that the correlation coefficient of 1hPG with HOMA-IR was similar to the correlation coefficient of 2hPG with HOMA-IR (0.493 vs. 0.480, P=0.550), while the correlation of 1hPG with adjusted HOMA-β was significantly stronger than that of 2hPG (-0.692 vs. -0.587, P<0.001). Excluding patients with T2DM, according to the cut point recommended by IDF, the AUC of 1hPG≥8.6 mmol/L for detecting prediabetes was 0.731 (95% CI: 0.714-0.748), and the sensitivity and specificity were 0.930 and 0.532, respectively, with the kappa value of 0.45. Conclusion:1hPG is closely related to insulin resistance and islet function, and there′s substantial value for individuals with a high risk of T2DM to detect prediabetes by using the 1hPG cut points recommended by IDF.

Objective To explore the influencing factors of neonatal pneumonia complicated with myocardial damage and Th1/Th2 cytokines,and construct a line chart model.Methods A total of 390 neonates with pneumonia who were treated in Mianyang People's Hospital were selected as the study subjects and randomly divided into a modeling cohort(n=273)and a validation cohort(n=117)according to a 7∶3 ratio.They were further divided into myocardial damage group and non-myocardial damage group according to whether they had concurrent myocardial damage.Enzyme linked immunosorbent assay(ELISA)was used to measure Th1/Th2 cytokines(IFN-γ,IL-6,TNF-α,IL-4,IL-2 and IL-10),and the Mindray BS-280 automatic biochemical analyzer was used to measure hs-cTn I,CK-MB,LDH and CK.Logistic regression equation was used to screen the influencing factors of neonatal pneumonia complicated with myocardial damage.R software was used to construct a line chart model,and the receiver operating characteristic curve(ROC)and area under the ROC curve(AUC)were used to analyze the predictive ability of the model.The Hosmer-Lemeshow goodness-of-fit test was used,and a calibration curve was drawn to evaluate the calibration of the model.The decision curve analysis(DCA)was used to evaluate the clinical effectiveness.Results The incidence of myocardial damage in 390 neonates with pneumonia was 28.21%.Modeling cohort and validetion cohort,the 1min Apgar score in the myocardial damage group was lower than that in the non-myocardial damage group(t=3.314,2.619),and CK-MB,LDH,CK,hs-cTnI,IL-2,IFN-γ,TNF-α,IL-6,IL-10 and IL-4 were higher than those in the non-myocardial damage group(t=5.805～18.914),and the proportions of severe pneumonia,low birthweight infant,premature infants were higher than those in the non-myocardial damage group(χ2=4.464～41.497),and the differences were statistically significant(all P<0.05),respectively.The Logistic regression equation showed that low birth weight,1-minute Apgar score,premature birth,hs-cTnI,IL-2,IFN-γ,IL-6 and IL-4 were factors affecting neonatal pneumonia complicated with myocardial damage(Wald χ2=10.330～14.328,all P<0.05).The AUC(95%CI)of the nomogram model constructed based on the factors affecting neonatal pneumonia complicated with myocardial damage was 0.880(0.839～0.921)in the modeling cohort and 0.910(0.856～0.964)in the validation cohort,with slopes of the calibration curves close to 1,and the clinical net benefit rate was the highest in the ranges of 0.1～0.8 and 0.0～0.7.Conclusion The nomogram model,which includes Th1/Th2 cytokines,hs-cTnI,1-minute Apgar score,premature infants and low-birth-weight infants has high predictive value for neonatal pneumonia complicated with myocardial damage.It can help clinicians identify high-risk populations,take reasonable diagnostic and treatment measures,and reduce the risk of myocardial damage.

Objective To establish the genetic typing detection technique of matrix-assisted laser de-sorption ionization-time or flight mass spectrometry(MALDI-TOF MS),and to apply it to investigate the polymorphism of the human platelet antigen(HPA)-29-35w low-frequency gene in blood donor population from Guangxi area.Methods The RS number of 7 target gene mutation sites in dbSNP and 21 primers were designed by using Assay Design Suite(ADS)of MassARRAY platform online primer design tool.Seven over-expression vectors inserting into HPA-29-35bb mutant sequence were constructed.Twenty-nine blood donors were randomly selected among the blood donors team in Guangxi area.The samples and vectors conducted the iPLEX Pro multiple genotyping analysis and mass spectrometric detection.Meanwhile,the above samples were sequenced and the sequencing results conducted the comparison validation with the mass spectrometric detec-tion results,then the MALDI-TOF MS genotyping detection technology was established.Then adopting this technology conducted the platelet antigen HPA-29-35W genotyping detection and polymorphism analysis in the samples from 588 blood donors in Guangxi area.Results The MALDI-TOF MS HPA genotyping detec-tion results were consistent with the sequencing results.The HPA-29-35w genotyping results showed that theHPA-29-35w genotype of 588 blood donors in Guangxi area was aa homozygote.Conclusion The genotype detection method of MALDI-TOF MS for HPA-29-35w is successfully established and applied to the screening of HPA-29-35w gene among the blood donor population in Guangxi area.

Metabolic dysfunction-associated steatohepatitis (MASH), a severe type of metabolic dysfunction-associated steatotic liver disease (MASLD), is a leading etiology of end-stage liver disease worldwide, posing significant health and economic burdens. microRNA-320 (miR-320), a ubiquitously expressed and evolutionarily conserved miRNA, has been reported to regulate lipid metabolism; however, whether and how miR-320 affects MASH development remains unclear. By performing miR-320 in situ hybridization with RNAscope, we observed a notable downregulation of miR-320 in hepatocytes during MASH, correlating with disease severity. Most importantly, miR-320 downregulation in hepatocytes exacerbated MASH progression as demonstrated that hepatocyte-specific miR-320 deficient mice were more susceptible to high-fat, high-fructose, high-cholesterol diet (HFHC) or choline-deficient, amino acid-defined, high-fat diet (CDAHFD)-induced MASH compared with control littermates. Conversely, restoration of miR-320 in hepatocytes ameliorated MASH-related steatosis and fibrosis by injection of adeno-associated virus 8 (AAV8) carrying miR-320 in different types of diet-induced MASH models. Mechanistic studies revealed that miR-320 specifically regulated fibroblast growth factor 1 (FGF1) production in hepatocytes by inhibiting regulator factor X1 (RFX1) expression. Notably, knockdown of Rfx1 in hepatocytes mitigated MASH by enhancing FGF1-mediated AMPK activation. Our findings underscore the therapeutic potential of hepatic miR-320 supplementation in MASH treatment by inhibiting RFX1-mediated FGF1 suppression.

Objective:To analyze the changes of intestinal flora in patients with benign and malignant colorectal tumors in high altitude areas and to compare them with the normal population in low altitude areas.Methods:The clinical data of 61 patients who underwent colonoscopy in the People's Hospital of Tibet Autonomous Region from 2020 to 2022 were collected as the high altitude group.According to the colonoscopy results,they were divided into control group(29 cases),non-adenomatous polyp group(12 cases),adenoma group(10 cases),colorectal cancer group(10 cases).17 patients who had negative colonoscopy results in the Peking University Third Hospital during the same period were collected as the low altitude control group.Before bowel preparation for colonoscopy,the fecal samples were collected.Then the DNA of bacteria in the fecal samples was extracted.The V3-V4 variable region of the 16S rRNA gene was PCR amplified and high-throughput sequenced.The species diversity of fecal flora was analyzed.Results:Alpha diversity analysis showed that the species diversity of samples from the high al-titude colorectal cancer group differed statistically from that of the high altitude non-adenomatous polyp group and the low altitude control group,and the species diversity of colorectal samples from the high al-titude colorectal cancer group was higher than that of the other two groups.While beta diversity showed no significant difference among the five groups.Differences were found in phylum level analysis that the abundance of Actinobacteriota in the low altitude control group was significantly lower than those in each group of the high altitude area,while the abundance of Actinobacteriota in the colorectal cancer group was significantly lower than those in the other 3 groups of the high altitude area.Differences were found in genus level analysis that the abundance of Bacteroides,Phascclarctobacterium and Lachnoclostridium in the low altitude control group was significantly higher than those of all the groups in the high altitude area;the abundance of Blautia and Collinsella in the high altitude control group was the highest.Lacto-bacillus was not detected in the low altitude control group,while there was a highly significant difference(P＜0.05)in the level of Lactobacillus in the four groups of high altitude area,and the abundance of Lactobacillus was significantly higher in the control group than those of the other three groups.In the four groups of samples at high altitude,the abundance of Bifidobacterium decreased significantly,while the abundance of Christensenellaceae_R-7_group increased significantly.Conclusion:Compared with the high and low altitude controls,the diversity and abundance of intestinal flora in patients with colorectal benign and malignant tumors at high altitudes are different.And the abundance of species are also diffe-rent at the phylum and genus levels,suggesting that altitude factors may have some influence on intestinal flora.