Humans ; Nutrition Assessment ; Prognosis ; Silicosis/prevention & control* ; Occupational Diseases ; China/epidemiology* ; Occupational Exposure ; Silicon Dioxide

OBJECTIVES: This study aimed to investigate the effect of new biomimetic micro/nano surfaces on the osteoclastic differentiation of RAW264.7 macrophages by simulating natural osteons for the design of concentric circular structures and modifying graphene oxide (GO). METHODS: The groups were divided into smooth titanium surface group (SS), concentric microgrooved titanium surface group (CMS), and microgroove modified with GO group (GO-CMS). The physicochemical properties of the material surfaces were studied using scanning electron microscopy (SEM), contact-angle measurement, atomic force microscopy, X-ray photoelectron spectroscopy analysis, and Raman spectroscopy. The effect of the modified material surface on the cell biological behavior of RAW264.7 was investigated by cell-activity assay, SEM, and laser confocal microscopy. The effect on the osteoclastic differentiation of macrophages was investiga-ted by tartrate-resistant acid phosphatase (TRAP) immunofluorescence staining and quantitative real-time polymerase chain reaction (qRT-PCR) experiments. RESULTS: Macrophages were arranged in concentric circles along the microgrooves, and after modification with GO, the oxygen-containing groups on the surface of the material increased and hydrophilicity increased. Osteoclasts in the GO-CMS group were small in size and number and had the lowest TRAP expression. Although it promoted the proliferation of macrophages in the GO-CMS group, the expression of osteoclastic differentiation-related genes was lower than that in the SS group, and the difference was statistically significant (P<0.05). CONCLUSIONS Concentric circular microgrooves restricted the fusion of osteoclasts and the formation of sealing zones. Osteomimetic concentric microgrooves modified with GO inhibited the osteoclastic differentiation of RAW 264.7 macrophages.
Graphite/pharmacology* ; Titanium/pharmacology* ; Haversian System ; Macrophages ; Cell Differentiation ; Oxides/pharmacology* ; Surface Properties

OBJECTIVE: To investigate the short-term effectiveness of transverse antecubital incision in the treatment of failed closed reduction of Gartland type Ⅲ supracondylar humeral fractures (SHFs) in children. METHODS: Between July 2020 and April 2022, 20 children with Gartland type Ⅲ SHFs who failed in closed reduction were treated with internal and external condylar crossing Kirschner wire fixation through transverse antecubital incision. There were 9 boys and 11 girls with an average age of 3.1 years (range, 1.1-6.0 years). The causes of injuries were fall in 12 cases and fall from height in 8 cases. The time from admission to operation ranged from 7 to 18 hours, with an average of 12.4 hours. The healing of the incision and the occurrence of complications such as nerve injury and cubitus varus were observed after operation; the elbow flexion and extension range of motion after removing the gypsum, after removing the Kirschner wire, and at last follow-up were recorded and compared, as well as the elbow flexion and extension and forearm rotation range of motion at last follow-up between healthy and affected sides; the Baumann angle was measured on the X-ray film, and the fracture healing was observed. At last follow-up, the effectiveness was evaluated according to the Flynn elbow function evaluation criteria. RESULTS: All incisions healed by first intention, and there was no skin necrosis, scar contracture, ulnar nerve injury, and cubitus varus. Postoperative pain occurred in the radial-dorsal thumb in 2 cases. The gypsum was removed and elbow flexion and extension exercises were started at 2-4 weeks (mean, 2.7 weeks) after operation, and the Kirschner wire was removed at 4-5 weeks (mean, 4.3 weeks). All the 20 patients were followed up 6-16 months, with an average of 12.4 months. The fracture healing time was 4-5 weeks, with an average of 4.5 weeks, and there was no complication such as delayed healing and myositis ossificans. The flexion and extension range of motion of the elbow joint gradually improved after operation, and there were significant differences between the time after removing the gypsum, after removing the Kirschner wire, and at last follow-up ( P<0.017). There was no significant difference in the flexion and extension of the elbow joint and the forearm rotation range of motion between the healthy and affected sides at last follow-up ( P>0.05). There was no significant difference in Baumann angle between the time of immediate after operation, after removing the Kirschner wire, and at last follow-up ( P>0.05). According to Flynn elbow function evaluation standard, 16 cases were excellent and 4 cases were good, the excellent and good rate was 100%. CONCLUSION The treatment of Gartland type Ⅲ SHFs in children with failed closed reduction by internal and external condylar crossing Kirschner wire fixation through transverse antecubital incision has the advantages of complete soft tissue hinge behind the fracture for easy reduction and wire fixation, small incision, less complications, fast fracture healing, early functional recovery, reliable reduction and fixation, and can obtain satisfactory results.
Male ; Female ; Humans ; Child ; Child, Preschool ; Calcium Sulfate ; Humerus ; Humeral Fractures/surgery* ; Plastic Surgery Procedures ; Fracture Fixation, Internal/methods* ; Bone Wires ; Fracture Healing ; Treatment Outcome ; Range of Motion, Articular

Objective: To identify the main metals involved in cognitive impairment in the Chinese oldest old, and explore the association between these metal exposures and cognitive impairment. Methods: A cross-sectional study was conducted on 1 568 participants aged 80 years and older from Healthy Aging and Biomarkers Cohort Study (2017 to 2018). Fasting venous blood was collected to measure the levels of nine metals (selenium, lead, cadmium, arsenic, antimony, chromium, manganese, mercury, and nickel). The cognitive function of these participants was evaluated by using the Chinese version of the Mini-Mental State Examination (CMMSE). The random forest (RF) was applied to independently identify the main metals that affected cognitive impairment. The multivariate logistic regression model and restricted cubic splines (RCS) model were used to further verify the association of the main metals with cognitive impairment. Results: The age of 1 568 study subjects was (91.8±7.6) years old, including 912 females (58.2%) and 465 individuals (29.7%) with cognitive function impairment. Based on the RF model (the out-of-bag error rate was 22.9%), the importance ranking of variables was conducted and the feature screening of five times ten-fold cross-validation was carried out. It was found that selenium was the metal that affected cognitive function impairment, and the other eight metals were not included in the model. After adjusting for covariates, the multivariate logistic regression model showed that with every increase of 10 μg/L of blood selenium levels, the risk of cognitive impairment decreased (OR=0.921, 95%CI: 0.889-0.954). Compared with the lowest quartile(Q₁) of blood selenium, the ORs (95%CI) of Q₃ and Q₄ blood selenium were 0.452 (0.304-0.669) and 0.419 (0.281-0.622) respectively. The RCS showed a linear dose-response relationship between blood selenium and cognitive impairment (P_nonlinear>0.05). Conclusion: Blood selenium is negatively associated with cognitive impairment in the Chinese oldest old.
Aged, 80 and over ; Female ; Humans ; Selenium ; Cohort Studies ; Cross-Sectional Studies ; Metals/analysis* ; Cognitive Dysfunction/epidemiology* ; China/epidemiology*

Objectives: To study the association between metals mixture exposure and DNA oxidative damage using mixture analysis methods, and to explore the most significant exposure factors that cause DNA oxidative damage. Methods: Workers from steel enterprises were recruited in Shandong Province. Urinary metals were measured by using the inductively coupled plasma mass spectrometry method. The level of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) was determined by using the ultra-high performance liquid chromatography-mass spectrometry method. Bayesian kernel machine regression (BKMR), elastic net regression and quantile g-computation regression were used to analyze the association between urinary metals and urinary 8-OHdG. Results: A total of 768 subjects aged (36.15±7.40) years old were included in the study. BKMR, elastic net regression and quantile g-computation all revealed an overall positive association between the mixture concentration and increased urinary 8-OHdG. The quantile g-computation results showed that with a 25% increase in metal mixtures, the urinary 8-OHdG level increased by 77.60%. The elastic net regression showed that with a 25% increase in exposure risk score, the urinary 8-OHdG level increased by 26%. The BKMR summarized the contribution of individual exposures to the response, and selenium, zinc, and nickel were significant contributors to the urinary 8-OHdG elevation. Conclusion: Exposure to mixed metals causes elevated levels of DNA oxidative damage, and selenium, zinc, and nickel are significant exposure factors.
Humans ; Adult ; Nickel/toxicity* ; Selenium ; Bayes Theorem ; Metals/toxicity* ; 8-Hydroxy-2'-Deoxyguanosine ; Oxidative Stress/physiology* ; Zinc ; DNA Damage

Objective: To investigate the spatial distribution characteristics and correlation between the prevalence of dental fluorosis and the chemical elemental composition of drinking water sources in coal-fired fluorosis areas. Methods: Based on the survey data on the prevalence of dental fluorosis at CDC in Guizhou Province in 2022, 274 original surface drinking water sources were collected in typical coal-fired fluorosis areas, and fluoride (F), calcium (Ca), magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), molybdenum (Mo), cadmium (Cd), barium (Ba), lead (Pb) 17 elements; apply Moran's I index, Getis-Ord Gi* hotspot analysis of the global spatial autocorrelation of chemical elements in drinking water and the degree of aggregation of each element on the local area, and correlation analysis with the prevalence of dental fluorosis in the region. Results: Except for Cu, Zn, and Cd, global spatial autocorrelation Moran's I was negative, and all other elements were positive. F, Ca, Al, Ti, As, Mo, Cd, and Cu elements showed high values of aggregation in the southeastern low-altitude area; Mg, Ba, Pb, Cr, Mn, and Fe elements were mainly aggregated in the central altitude terrain transition area, Zn and Se elements in water sources are significantly positively correlated with the prevalence of dental fluorosis (P<0.05). In contrast, F, Mg, Al, Ti, As, Mo, Cd, Ba, and Pb elements negatively correlate (P<0.05). Elements in the central region were high-high aggregation, as a hot spot aggregation area with high disease incidence, while F, Al, Mn, Mo, Cd, and Ba elements in the western region were low-low aggregation, as a cold spot aggregation area with a low incidence of fluorosis. Conclusions: The risk of population fluoride exposure in surface drinking water sources is shallow. However, the chemical element content of drinking water sources in coal-fired polluted endemic fluorosis areas has prominent spatial geographical distribution characteristics. There is a significant spatial aggregation effect with the prevalence of dental fluorosis, which may play a synergistic or antagonistic effect on the occurrence and prevalence of dental fluorosis.
Humans ; Drinking Water ; Prevalence ; Coal ; Fluorides/adverse effects* ; Cadmium ; Fluorosis, Dental/epidemiology* ; Lead ; Selenium ; Arsenic

Objective: To understand the exposure level of dust and noise in the mining industry and provide data support for revising policy for the prevention and control of occupational diseases. Methods: In May 2022, Data was collected through the National Surveillance Program for Occupational Hazards in the Workplace. Descriptive analysis was conducted for dust and noise levels by industry type and enterprise size from 7, 679 enterprises in the mining industry among 29 provincial regions nationwide. Results: The enterprises in the mining industry included in the National Surveillance Program for Occupational Hazards in the Workplace are mainly small and micro, accounting for 47.97% (3684/7679) and 30.00% (230/7679) respectively. The industry is mainly compred of employers in the non-metallic ming and beneficiation industry, accounting for 50.25% (3859/7679). Among the enterprises with silica dust, coal dust, and noise hazards, the proportion of enterprises where total dust concentration and noise intensity exceed the standard is higher than 50%. 30% of the posts are with an exposure level of silica dust, coal dust, and noise that exceeds the standard. The exceedance rate and the median of the time-weighted average concentration of total coal dust among large and medium-sized enterprises are higher than those among small and micro-sized enterprises (P<0.05) . Conclusion: The dust and noise hazards in the mining industry are lower than in the past in China, but more than 25% of workers are still at a high risk of occupational pneumoconiosis and noise deafness. Therefore, intervention and surveillance strategies should be strengthened in the future.
Humans ; Dust/analysis* ; Occupational Exposure/analysis* ; Occupational Health ; Coal ; Silicon Dioxide/analysis* ; Coal Mining

Objective: Through comparative analysis of the disease burden of occupational pneumoconiosis in Gansu Province from 2010 to 2020, the main influencing factors are screened, and scientific basis is provided for rational allocation of limited health resources, precise management and policy implementation. Methods: In August 2021, survey and collect information on surviving occupational pneumoconiosis patients and dead occupational pneumoconiosis patients diagnosed in Gansu Province from 2010 to 2020, and analyze and calculate indicators such as morbidity, mortality, and disability adjusted of life years (DALY). Analyzing the influencing factors of disease burden usirrg multiple linear regression. Results: From 2010 to 2020, the average annual incidence of occupational pneumoconiosis in Gansu Province was 0.9992/100000, the average annual mortality was 0.897/100000, the cumulative case fatality rate was 25.75%, and the cumulative DALY was 28932.96 person-years. The first stage of occupational pneumoconiosis was the highest among DALY loss (19920.14 person-years), and the DALY loss was positively correlated with the stage of occupational pneumoconiosis. Among occupational pneumoconiosis in Gansu Province, silicosis (13753.66 person-years) and coal worker's pneumoconiosis (13414.73 person-years) caused the highest disease burden, followed by cement pneumoconiosis and asbestos lung. Period, length of service, type of disease, and region are all influencing factors of DALY loss (P<0.05). Conclusion: From 2010 to 2020, the DALY losses caused by occupational pneumoconiosis in Gansu Province showed a fluctuating decrease, with the composition of DALY mainly changing from the loss of life years due to premature death to the loss of years due to injury and disability.
Humans ; Pneumoconiosis/epidemiology* ; Silicosis/epidemiology* ; Anthracosis/epidemiology* ; Asbestos ; Cost of Illness ; China/epidemiology*

OBJECTIVE: To explore the influence of the thickness of mixed cardboard on the compressive strength of glass ionomer cement and the associated factors. METHODS: Three different types of glass ionomer cements were mixed on the top of 60, 40, 20 and 1 pieces of paper (P60, P40, P20 and P1), respectively. The compressive strength of the materials was tested after solidification, and the bubble rate was calculated with the assistance of scanning electron microscope. RESULTS: (1) Compressive strength: ① ChemFil Superior glass ionomer (CF): The average compressive strength of P1 group was the highest, which was significantly different from that of P40 and P60 groups (P values were 0.041 and 0.032 respectively); ② To Fuji IX GP glass ionomer (IX): The average compressive strength of P1 group was the highest, which was statistically different from that of P40 and P60 groups (P values were 0.042 and 0.038 respectively); ③ Glaslonomer FX-Ⅱ glass ionomer cement (FX): The average compressive strength of P1 group was the highest, which was statistically different from that of P20, P40 and P60 groups (P values were 0.031, 0.040 and 0.041 respectively), but there was no statistical difference among the other groups. All the three materials showed that the compressive strength of glass ions gradually increased with the decrease of the thickness of the blended paperboard, and the two materials had a highly linear negative correlation, the correlation coefficients of which were CF-0.927, IX-0.989, FX-0.892, respectively. (2) Scanning electron microscope: P1 group had the least bubbles among the three materials. CONCLUSION It indicates that the thickness of mixed cardboard has a negative correlation with the compressive strength of glass ions. The thicker the mixed cardboard is, the greater the elasticity is. Excessive elasticity will accelerate the mixing speed when the grinding glass ions. Studies have shown that the faster the speed of artificial mixing is, the more bubbles is produced.The thicker ther mixed cardboard is, the more bubblesn are generated by glass ionomer cement, and the higher the compressive strength is. Using one piece of paper board to mix glass ionomer cement has the least bubbles and can obtain higher compressive strength.
Compressive Strength ; Materials Testing ; Glass Ionomer Cements ; Silicon Dioxide

OBJECTIVE: To investigate the effects of novel bioactive glasses (BG) including PSC with high phosphorus component and FBG with fluorine-doped element on promoting remineralization of artificial dentin caries. METHODS: (1) BGs were used in this study as follows: PSC (10.8%P₂O₅-54.2%SiO₂-35.0%CaO, mol.%) were synthesized using phytic acid as the phosphorus precursor through sol-gel method. FBG (6.1%P₂O₅-37.0%SiO₂-53.9%CaO-3.0%CaF₂, mol.%) and 45S5(6.0%P₂O₅-45.0%SiO₂-24.5%CaO-24.5%Na₂O, mol.%) were synthesized by traditional melt method. (2) The above BGs were soaked in simulated body fluid (SBF) for 24 hours. Then X-ray diffraction (XRD) was used to analyze the formation of hydroxyapatite (HA) crystals. (3) Prepared 1 mm thick dentin slices were soaked in 17% ethylene diamine tetraacetic acid (EDTA) for 1 week to demineralize the dentin. Then the dentin slices treated by BG were soaked in SBF for 1 week. Field emission scanning electron micro-scopy (FE-SEM) was used to observe the surface morphology of the dentin slices. (4) Four cavities were prepared to 1 mm depth in each 2 mm thick dentin slice, then were treated with lactic acid for 2 weeks to form the artificial dentin caries. Wax, mineral trioxide aggregate (MTA), PSC and FBG were used to fill four cavities as blank control group, MTA group, PSC group and FBG group respectively. Then the spe-cimens were soaked in SBF for 4 weeks. The changes of depth and density of demineralized dentin were analyzed using Micro-CT before filling and after 2 and 4 weeks filling. RESULTS: (1) PSC and FBG promoted mineral formation on the surfaces of the demineralized dentin. And the speed was faster and crystallinity was higher in PSC group than the FBG and 45S5 groups. (2) The increased mineral density of artificial dentin caries in PSC group were (185.98 ± 55.66) mg/cm³ and (213.64 ± 36.01) mg/cm³ 2 and 4 weeks after filling respectively, which were significantly higher than the control group [(20.38 ± 7.55) mg/cm³, P=0.006; (36.46 ± 10.79) mg/cm³, P=0.001]. At meanwhile, PSC group was also higher than MTA group [(57.29 ± 10.09) mg/cm³; (111.02 ± 22.06) mg/cm³], and it had statistical difference (P=0.015; P=0.006). The depth of remineralized dentin in PSC group were (40.0 ± 16.9) μm and (54.5 ± 17.8) μm 2 and 4 weeks respectively, which were also statistically different from the control group (P =0.010;P=0.001). There were no statistical differences between the control group and MTA group. The above effects of FBG group were between PSC and MTA. CONCLUSION PSC has advantages in the speed, quality and depth of mineral deposition in the demineralized layer of artificial dentin caries. It would be expected to be an ideal material to promote the remineralization of dentin caries.
Dentin ; Silicon Dioxide/pharmacology* ; Dental Caries Susceptibility ; Minerals/pharmacology* ; Phosphorus/pharmacology* ; Tooth Remineralization/methods*