ObjectiveTo analyze the measures and effects of comprehensive noise control in an automobile engine manufacturing enterprise. Methods An automobile engine manufacturing enterprise with noise exposure work-sites was selected as the research subject. The noise hazard status of the enterprise was investigated. The noise hazard exceeded the national standard in work-sites was comprehensively treated. The treatment effect was analyzed. Results A total of 395 work-sites exposed to noise were detected. Among them, 16 work-sites exceeded the national noise standard, with the rate of 4.1%. The work-sites with noise exceeding the national standard were mainly in the machine workshop and the casting workshop, with normalization of equivalent continuous A-weighted sound pressure level to a nominal eight hours working day (L_EX,8h) ranging from 86.8 to 89.2 and 85.2 to 90.2 dB(A), respectively. In addition, the classification of occupational noise exposure of the mold protection group in the casting workshop was level Ⅱ, and classification of occupational noise exposure of other work-sites with excessive national standard was grade Ⅰ. After the enterprise implemented noise control measures such as process reform, equipment replacement, sound insulation, noise reduction, sound absorption, and vibration isolation, the L_EX,8h of nine positions were lower than those before rectification ［(86.7±1.1) vs (83.3±1.3) dB(A), P<0.01］. Conclusion The use of comprehensive control measures can achieve the purpose of reducing noise from the sources, and can be used for reference by relevant enterprises with noise hazards.

Objective To develop a ventilation system for the enhaned mobile biosafety level-2(BSL-2)laboratory to control the dispersed aerosol within the laboratory effectively.Methods A ventilation system for the enhanced mobile biosafety level-2 laboratory was designed with the concept of full fresh air ventilation,which realized air supply with 3-stage filtration and constant air volume control,and air exhaust with 1-stage high-efficiency filtration and variable air volume control.The buffer room had the layout of upside air supply and upside exhaust,with the air supply and exhaust equipment integrated into the ceiling;the experimental room had the layout of diagonally upside air supply and diagonally downside exhaust.Computa-tional fluid dynamics(CFD)software was used to analyze the airflow organization,temperature field and velocity field at 0°,30°,45°,60° and 90° air supply angles in order to verify the feasibility of the ventilation system design,and the distributions of aerosol concentration in the experimental room at different air supply angles were simulated to determine the optimal air supply angle.Results Investigations in terms of airflow organization,temperature field,velocity field and aerosol dispersion control showed in case of 60° air supply angel the enhanced mobile BSL-2 laboratory behaved the best and its core indexes all met the requirements of GB 27421-2015 Mobile laboratories—Generalrequirements for biosafety and T/CESC 662-2020 Architectural technical standard for BSL-2 laboratory in medical facilities including the number of air changes,static pressure difference,temperature and humidity,cleanliness and airflow direction.Conclusion Considerations have to be taken on the locations of supply and exhaust outlets,the facility layout and air supply angle when the enhanced mobile BSL-2 laboratory is designed so as to enhance the biosafety of the protective area.[Chinese Medical Equipment Journal,2024,45(7):29-34]

Humans ; Mpox (monkeypox) ; China

OBJECTIVES: To investigate the prevalence rate of non-alcoholic fatty liver disease (NAFLD) in overweight/obese children who visit a hospital, and to explore the influencing factors of NAFLD, in order to provide a basis for the prevention of NAFLD in overweight/obese children. METHODS: Overweight/obese children who visited Hunan Children's Hospital from June 2019 to September 2021 were recruited. The prevalence rate of NAFLD was examined. Logistic regression analysis was used to explore the factors influencing the development of NAFLD [non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH)]. Receiver operating characteristic curve analysis was used to evaluate the predictive value of the influencing factors for NAFL and NASH. RESULTS: A total of 844 overweight/obese children aged 6-17 years were enrolled. The prevalence rate of NAFLD in overweight/obese children was 38.2% (322/844), among which the prevalence rates of NAFL and NASH were 28.8% (243/844) and 9.4% (79/844), respectively. Multivariate logistic regression analysis showed that the increase of waist-to-hip ratio (WHR) and low high-density lipoprotein cholesterol (HDL-C) were associated with the development of NAFL and NASH (P<0.05). The receiver operating characteristic curve analysis showed that the combined measurement of WHR and HDL-C had a predictive value for NAFL (area under the curve: 0.653, 95%CI: 0.613-0.694), and for NASH (area under the curve: 0.771, 95%CI: 0.723-0.819). CONCLUSIONS The prevalence rate of NAFLD in overweight/obese children who visit a hospital is high. WHR and HDL-C are associated with the development of NAFLD and the combined measurement of WHR and HDL-C has a certain value for predicating the development of NAFLD.
Child ; Humans ; Cholesterol, HDL ; Cross-Sectional Studies ; Non-alcoholic Fatty Liver Disease/complications* ; Overweight/complications* ; Pediatric Obesity/epidemiology* ; Prevalence ; Adolescent

Objective: To explore the heterogeneity and correlation of clinical phenotypes and genotypes in children with disorders of sex development (DSD). Methods: A retrospective study of 1 235 patients with clinically proposed DSD in 36 pediatric medical institutions across the country from January 2017 to May 2021. After capturing 277 DSD-related candidate genes, second-generation sequencing was performed to analyzed the heterogeneity and correlation combined with clinical phenotypes. Results: Among 1 235 children with clinically proposed DSD, 980 were males and 255 were females of social gender at the time of initial diagnosis with the age ranged from 1 day of age to 17.92 years. A total of 443 children with pathogenic variants were detected through molecular genetic studies, with a positive detection rate of 35.9%. The most common clinical phenotypes were micropenis (455 cases), hypospadias (321 cases), and cryptorchidism (172 cases) and common mutations detected were in SRD5A2 gene (80 cases), AR gene (53 cases) and CYP21A2 gene (44 cases). Among them, the SRD5A2 mutation is the most common in children with simple micropenis and simple hypospadias, while the AMH mutation is the most common in children with simple cryptorchidism. Conclusions: The SRD5A2 mutation is the most common genetic variant in Chinese children with DSD, and micropenis, cryptorchidism, and hypospadias are the most common clinical phenotypes. Molecular diagnosis can provide clues about the biological basis of DSD, and can also guide clinicians to perform specific clinical examinations. Target sequence capture probes and next-generation sequencing technology can provide effective and economical genetic diagnosis for children with DSD.
3-Oxo-5-alpha-Steroid 4-Dehydrogenase/genetics* ; Child ; China/epidemiology* ; Cryptorchidism/genetics* ; Disorders of Sex Development/genetics* ; Female ; Genital Diseases, Male ; Genotype ; Humans ; Hypospadias/genetics* ; Male ; Membrane Proteins/genetics* ; Penis/abnormalities* ; Phenotype ; Retrospective Studies ; Steroid 21-Hydroxylase/genetics*

OBJECTIVE: To explore the interaction between reactive oxygen species (ROS) and ferroptosis in methylglyoxalinduced injury of mouse embryonic osteoblasts (MC3T3-E1 cells). METHODS: MC3T3-E1 cells were treated with methylglyoxal to establish a cell model of diabetic osteoporosis. CCK-8 assay was used to detect the viability of MC3T3-E1 cells. Rhodamine 123 staining followed by photofluorography was used to examine mitochondrial membrane potential (MMP). The intracellular ROS level was detected by 2', 7'-dichlorodihydrofluorescein diacetate staining with photofluorograph. Alkaline phosphatase (ALP) activity in the cells was detected using an ALP kit, the number of mineralized nodules was determined with alizarin red S staining, and the level of iron ions was detected using a detection kit. The expression level of glutathione peroxidase 4 (GPX4, a marker protein that inhibits ferroptosis) in the osteoblasts was determined using Western blotting. RESULTS: Treatment of MC3T3-E1 cells with 0.6 mmol/L methylglyoxal for 24 h significantly inhibited the expression level of GPX4 (P < 0.001), increased intracellular iron ion concentration, decreased the cell viability, increased the loss of MMP and intracellular ROS level, decreased both ALP activity and the number of mineralized nodules in the cells (P < 0.001). Co-treatment of MC3T3-E1 cells with 2 mmol/L N-acetylcysteine (NAC, a ROS scavenger) and methylglyoxal significantly increased the expression level of GPX4 (P < 0.01); co-treatment with 4 mmo/L FER-1 (a ferroptosis inhibitor) and methylglyoxal obviously decreased the intracellular ROS level (P < 0.001). Co-treatment of the cells either with NAC and methylglyoxal or with FER-1 and methylglyoxal attenuated methylglyoxal-induced injuries in the osteoblasts (P < 0.001). CONCLUSION The interaction between ROS and ferroptosis pathway plays an important role in methylglyoxal-induced injury of mouse embryonic osteoblasts.
Animals ; Cell Survival ; Ferroptosis ; Mice ; Osteoblasts ; Pyruvaldehyde/metabolism* ; Reactive Oxygen Species/metabolism*

OBJECTIVE: To investigate the changes in bacterial flora in fecal samples, at the tumor loci and in adjacent mucosa in patients with colorectal cancer (CRC). METHODS: We collected fecal samples from 13 patients with CRC and 20 healthy individuals and tumor and adjacent mucosa samples from 6 CRC patients. The differences in bacterial composition between the fecal and mucosa samples were analyzed with 16S rDNA sequencing and bioinformatics methods. We also detected the total number of bacteria in the feces using flow cytometry, isolated and identified the microorganisms in the fecal and mucosa samples using common bacterial culture media. We further tested the effects of 7 isolated bacterial strains on apoptosis of 3 CRC cell lines using lactate dehydrogenase detection kit. RESULTS: The bacterial α-diversity in the feces of healthy individuals and in adjacent mucosa of CRC patients was significantly higher than that in the feces and tumor mucosa in CRC patients (P < 0.05). Lactobacillaceae is a specific bacteria in the feces, while Escherichia, Enterococcus, and Fusobacterium are specific bacteria in tumor mucosa of CRC patients as compared with healthy individuals. Cell experiment with3 CRC cell lines showed that Bacteroides fragilis isolated from the tumor mucosa of CRC patients produced significant inhibitory effects on cell proliferation (P < 0.0001), while the isolated strain Fusobacterium nucleatum obviously promoted the proliferation of the cell lines (P < 0.001). CONCLUSION The bacterial flora in the feces, tumor mucosa and adjacent mucosa of CRC patients is significantly different from that in the feces of healthy individuals, and the fecal flora of CRC patients can not represent the specific flora of the tumor mucosa. Inhibition of F. nucleatum colonization in the tumor mucosa and promoting B. fragilis colonization may prove beneficial for CRC treatment.
Bacteria ; Colorectal Neoplasms/pathology* ; Feces/microbiology* ; Gastrointestinal Microbiome ; Humans ; Intestinal Mucosa

Many studies have shown that high-altitude exposure could significantly influence human cognition, and the approaches which could enhance the human cognition in high-altitude hypoxia environment attract great attention. In the present study, we recruited a total of 60 subjects who had been migrated to Tibet University as adults for more than one year. These participants were randomly divided into the experimental group and the control group. The participants in the experimental group were instructed to complete a hyperbaric oxygen treatment, and those in the control group just completed a wait condition. By using the attention network test (ANT), the changes of the attention function before and after a single session of hyperbaric oxygen treatment were explored. The results showed that single hyperbaric oxygen treatment significantly improved the orienting function of attention, with an obvious post-intervention effect, but not the alerting and conflict function of attention. We also found a strong association between alerting function and conflict function after the end of intervention, suggesting the change of the overall performance of attention function. The present findings might suggest that the improvement of attention function by a single session of hyperbaric oxygen intervention is derived from the increase of general cognitive resources, rather than the transfer of cognitive resources within the attention system.
Adult ; Humans ; Hyperbaric Oxygenation ; Orientation ; Oxygen ; Reaction Time ; Tibet ; Transients and Migrants

Perilla frutescens is a traditional medicinal and edible plant widely distributed in China and enjoys an extensive usage. P. frutescens contains multiple essential oils， which are composed of monoterpenes， sesquiterpenes， and their oxygen-containing derivatives. Compared with other parts of P. frutescens， Perillae Folium produce more oils， with volatile oils as the main constituents. There are many active substances in the volatile oils from Perillae Folium， mainly including perillaldehyde， perillaketone， perillaalcohol， D-limonene， β-caryophylene， etc. Such factors as germplasm， growth environment， extraction method， cultivation time， and harvest period all can trigger changes in volatile oil constituents and content from Perillae Folium. The volatile oils from Perillae Folium have diverse pharmacological effects like anti-oxidation， anti-bacteria， anti-inflammation， vasodilation， anti-tumor， and anti-depression， implying its high clinical application value. However， the chemical constituents in volatile oils from Perillae Folium are complex and unstable and their pharmacological activities are affected by many factors， so the safety and effectiveness of clinical medication fail to be guaranteed， which may has impeded the rational and effective use of these volatile oils. Many scholars in China and abroad have conducted a lot of research on the volatile oils from Perillae Folium， but there is currently no systematic and comprehensive research report on the chemical constituents of volatile oils from Perillae Folium and their pharmacological effects. This paper reviewed the relevant domestic and foreign literature， analyzed the development status of volatile oils from Perillae Folium， and summarized their extraction process， chemical constituents， and pharmacological actions， aiming to provide a reference for their further development， clinical application， and risk assessment.

OBJECTIVE: To investigate the phenolic composition, antioxidant properties, and hepatoprotective mechanisms of polyphenols from green tea extract (GTP) in carbon tetrachloride (CCl)-induced acute liver injury mouse model. METHODS: High-performance liquid chromatography was used to analyze the chemical composition of the extract. Antioxidant activity of GTP was assessed by O, OH, DPPH, and ferric-reducing antioxidant power (FRAP) assay in vitro. Sixty Kunming mice were divided into 6 groups including control, model, low-, medium-, and high-doses GTP (200, 400, 800 mg/kg) and vitamin E (250 mg/kg) groups, 10 in each group. GTP and vitamin E were administered at a level of abovementioned doses twice per day for 7 days prior to exposure to a single injection of CCl. Hepatoprotective effects of GTP were evaluated in a CCl-induced mouse model of acute liver injury, using commercial enzyme linked immunosorbent assay kits, histopathological observation, terminal deoxynucleotidyl transferase-mediated dUTPNick-end labeling (TUNEL) assay and Western blot. RESULTS: GTP contained 98.56 µg gallic acid equivalents per milligram extract total polyphenols, including epicatechingallate, epigallocatechin gallate, epicatechin, and epigallocatechin. Compared with the model group, low-, medium-, or high doses GTP significantly decreased serum levels of alanine aminotransferase and aspartate transaminase (P<0.01). Histopathological observation confirmed that pretreatment of GTP prevented swelling and necrosis in CCl-exposed hepatocytes. Hepatoprotective effects of low-, medium-, and high-dose GTP were associated with eliminating free radicals and improving superoxide dismutase, catalase, and glutathione peroxidase activity in the liver. Additionally, low-, medium-, and high-dose GTP decreased cell apoptosis in the CCl-exposed liver (P<0.01). Phosphorylated nuclear factor kappa-B (NF-κB), p53, Bcl-2 associated x protein/B-cell lymphoma/leukemia-2 gene, cytochrome C, and cleaved caspase-3 levels were downregulated compared with the model group (P<0.01). CONCLUSION GTP achieves hepatoprotective effects by improving hepatic antioxidant status and preventing cell apoptosis through caspase-3-dependent signaling pathways.