BACKGROUND:Iron overload is an independent factor inducing osteoporosis,but the action mechanism is currently unclear.Therefore,exploring the effects of iron overload on osteoblast-related cells will help to deeply understand the pathogenesis of osteoporosis and provide potential strategies for osteoporosis treatment.OBJECTIVE:To explore the effects of iron overload environment on osteoblast precursor cell activity,ferroptosis,and osteogenic differentiation.METHODS:Osteoblast precursor cells(MC3T3-E1 cells)were divided into blank group,iron overload group,fer-1 group,and deferoxamine group.The iron overload group was treated with 300 μmol/L ammonium ferric citrate in the culture medium for 48 hours to simulate the iron overload microenvironment.The cells in fer-1 group and deferoxamine group were pretreated with 5 μmol/L antioxidant fer-1 and 5 μmol/L deferoxamine for 8 hours,respectively,and then added with 300 μmol/L ammonium ferric citrate for 48 hours.CCK-8 assay was used to determine the cell viability.Intracellular reactive oxygen species levels were detected employing a reactive oxygen species fluorescent probe.Changes in mitochondrial membrane potential were monitored with a mitochondrial membrane potential fluorescent probe.Mitochondrial morphology was observed employing transmission electron microscopy.Cellular glutathione levels were measured with a reduced glutathione colorimetric assay kit.Lipid peroxidation levels were assessed with a malondialdehyde colorimetric assay kit.Cellular ferrous ion levels were determined with a ferrous ion colorimetric assay kit.The osteogenic and mineralization capabilities of the cells were verified by alkaline phosphatase staining and alizarin red staining.Collagen secretion ability was detected using Sirius Red staining.The expression of osteogenic/ferroptosis-related genes and proteins was examined through reverse transcription quantitative polymerase chain reaction and western blot analysis.RESULTS AND CONCLUSION:(1)In an iron-overload environment,the mitochondrial membrane potential of cells decreased and their structure was compromised,with an elevation in intracellular lipid peroxidation levels and a downregulation of genes and proteins associated with ferroptosis resistance.However,pretreatment with fer-1 and deferoxamine led to an increase in mitochondrial membrane potential and partial restoration of morphology,a reduction in intracellular lipid peroxidation levels,and an upregulation of genes and proteins related to ferroptosis resistance.(2)In an iron-overload environment,the levels of cellular alkaline phosphatase,the formation of mineralized nodules,and the synthesis of collagen fibers were all found to be decreased.Pretreatment with fer-1 and deferoxamine was observed to upregulate the expression of osteogenic differentiation in cells.(3)In summary,iron overload could increase intracellular oxidative stress levels,mediate ferroptosis in MC3T3-E1 cells and inhibit osteogenic differentiation,thereby inducing osteoporosis.Therefore,maintaining iron homeostasis and inhibiting osteogenesis-related ferroptosis may be potential strategies to prevent or treat osteoporosis.

BACKGROUND:Iron overload is an independent factor inducing osteoporosis,but the action mechanism is currently unclear.Therefore,exploring the effects of iron overload on osteoblast-related cells will help to deeply understand the pathogenesis of osteoporosis and provide potential strategies for osteoporosis treatment.OBJECTIVE:To explore the effects of iron overload environment on osteoblast precursor cell activity,ferroptosis,and osteogenic differentiation.METHODS:Osteoblast precursor cells(MC3T3-E1 cells)were divided into blank group,iron overload group,fer-1 group,and deferoxamine group.The iron overload group was treated with 300 μmol/L ammonium ferric citrate in the culture medium for 48 hours to simulate the iron overload microenvironment.The cells in fer-1 group and deferoxamine group were pretreated with 5 μmol/L antioxidant fer-1 and 5 μmol/L deferoxamine for 8 hours,respectively,and then added with 300 μmol/L ammonium ferric citrate for 48 hours.CCK-8 assay was used to determine the cell viability.Intracellular reactive oxygen species levels were detected employing a reactive oxygen species fluorescent probe.Changes in mitochondrial membrane potential were monitored with a mitochondrial membrane potential fluorescent probe.Mitochondrial morphology was observed employing transmission electron microscopy.Cellular glutathione levels were measured with a reduced glutathione colorimetric assay kit.Lipid peroxidation levels were assessed with a malondialdehyde colorimetric assay kit.Cellular ferrous ion levels were determined with a ferrous ion colorimetric assay kit.The osteogenic and mineralization capabilities of the cells were verified by alkaline phosphatase staining and alizarin red staining.Collagen secretion ability was detected using Sirius Red staining.The expression of osteogenic/ferroptosis-related genes and proteins was examined through reverse transcription quantitative polymerase chain reaction and western blot analysis.RESULTS AND CONCLUSION:(1)In an iron-overload environment,the mitochondrial membrane potential of cells decreased and their structure was compromised,with an elevation in intracellular lipid peroxidation levels and a downregulation of genes and proteins associated with ferroptosis resistance.However,pretreatment with fer-1 and deferoxamine led to an increase in mitochondrial membrane potential and partial restoration of morphology,a reduction in intracellular lipid peroxidation levels,and an upregulation of genes and proteins related to ferroptosis resistance.(2)In an iron-overload environment,the levels of cellular alkaline phosphatase,the formation of mineralized nodules,and the synthesis of collagen fibers were all found to be decreased.Pretreatment with fer-1 and deferoxamine was observed to upregulate the expression of osteogenic differentiation in cells.(3)In summary,iron overload could increase intracellular oxidative stress levels,mediate ferroptosis in MC3T3-E1 cells and inhibit osteogenic differentiation,thereby inducing osteoporosis.Therefore,maintaining iron homeostasis and inhibiting osteogenesis-related ferroptosis may be potential strategies to prevent or treat osteoporosis.

Background: This study aimed to estimate temporal trends in metabolically unhealthy obesity (MUO) among United States (US) adults by age, sex, race/ethnicity, and income from 1999 to 2018. Methods: We included 17,230 non-pregnant adults from a nationally representative cross-sectional study, the National Health and Nutrition Examination Survey (NHANES). MUO was defined as body mass index ≥30 kg/m2 with any metabolic disorders in blood pressure, blood glucose, and blood lipids. The age-adjusted percentage of MUO was calculated, and linear regression models estimated trends in MUO. Results: The weighted mean age of adults was 47.28 years; 51.02% were male, 74.64% were non-Hispanic White. The age-adjusted percentage of MUO continuously increased in adults across all subgroups during 1999–2018, although with different magnitudes (all P<0.05 for linear trend). Adults aged 45 to 64 years consistently had higher percentages of MUO from 1999–2000 (34.25%; 95% confidence interval [CI], 25.85% to 42.66%) to 2017–2018 (42.03%; 95% CI, 35.09% to 48.97%) than the other two age subgroups (P<0.05 for group differences). The age-adjusted percentage of MUO was the highest among non-Hispanic Blacks while the lowest among non-Hispanic Whites in most cycles. Adults with high-income levels generally had lower MUO percentages from 1999–2000 (22.63%; 95% CI, 17.00% to 28.26%) to 2017–2018 (32.36%; 95% CI, 23.87% to 40.85%) compared with the other two subgroups. Conclusion This study detected a continuous linear increasing trend in MUO among US adults from 1999 to 2018. The persistence of disparities by age, race/ethnicity, and income is a cause for concern. This calls for implementing evidence-based, structural, and effective MUO prevention programs.

Background: This study aimed to estimate temporal trends in metabolically unhealthy obesity (MUO) among United States (US) adults by age, sex, race/ethnicity, and income from 1999 to 2018. Methods: We included 17,230 non-pregnant adults from a nationally representative cross-sectional study, the National Health and Nutrition Examination Survey (NHANES). MUO was defined as body mass index ≥30 kg/m2 with any metabolic disorders in blood pressure, blood glucose, and blood lipids. The age-adjusted percentage of MUO was calculated, and linear regression models estimated trends in MUO. Results: The weighted mean age of adults was 47.28 years; 51.02% were male, 74.64% were non-Hispanic White. The age-adjusted percentage of MUO continuously increased in adults across all subgroups during 1999–2018, although with different magnitudes (all P<0.05 for linear trend). Adults aged 45 to 64 years consistently had higher percentages of MUO from 1999–2000 (34.25%; 95% confidence interval [CI], 25.85% to 42.66%) to 2017–2018 (42.03%; 95% CI, 35.09% to 48.97%) than the other two age subgroups (P<0.05 for group differences). The age-adjusted percentage of MUO was the highest among non-Hispanic Blacks while the lowest among non-Hispanic Whites in most cycles. Adults with high-income levels generally had lower MUO percentages from 1999–2000 (22.63%; 95% CI, 17.00% to 28.26%) to 2017–2018 (32.36%; 95% CI, 23.87% to 40.85%) compared with the other two subgroups. Conclusion This study detected a continuous linear increasing trend in MUO among US adults from 1999 to 2018. The persistence of disparities by age, race/ethnicity, and income is a cause for concern. This calls for implementing evidence-based, structural, and effective MUO prevention programs.

Background: This study aimed to estimate temporal trends in metabolically unhealthy obesity (MUO) among United States (US) adults by age, sex, race/ethnicity, and income from 1999 to 2018. Methods: We included 17,230 non-pregnant adults from a nationally representative cross-sectional study, the National Health and Nutrition Examination Survey (NHANES). MUO was defined as body mass index ≥30 kg/m2 with any metabolic disorders in blood pressure, blood glucose, and blood lipids. The age-adjusted percentage of MUO was calculated, and linear regression models estimated trends in MUO. Results: The weighted mean age of adults was 47.28 years; 51.02% were male, 74.64% were non-Hispanic White. The age-adjusted percentage of MUO continuously increased in adults across all subgroups during 1999–2018, although with different magnitudes (all P<0.05 for linear trend). Adults aged 45 to 64 years consistently had higher percentages of MUO from 1999–2000 (34.25%; 95% confidence interval [CI], 25.85% to 42.66%) to 2017–2018 (42.03%; 95% CI, 35.09% to 48.97%) than the other two age subgroups (P<0.05 for group differences). The age-adjusted percentage of MUO was the highest among non-Hispanic Blacks while the lowest among non-Hispanic Whites in most cycles. Adults with high-income levels generally had lower MUO percentages from 1999–2000 (22.63%; 95% CI, 17.00% to 28.26%) to 2017–2018 (32.36%; 95% CI, 23.87% to 40.85%) compared with the other two subgroups. Conclusion This study detected a continuous linear increasing trend in MUO among US adults from 1999 to 2018. The persistence of disparities by age, race/ethnicity, and income is a cause for concern. This calls for implementing evidence-based, structural, and effective MUO prevention programs.

Background: This study aimed to estimate temporal trends in metabolically unhealthy obesity (MUO) among United States (US) adults by age, sex, race/ethnicity, and income from 1999 to 2018. Methods: We included 17,230 non-pregnant adults from a nationally representative cross-sectional study, the National Health and Nutrition Examination Survey (NHANES). MUO was defined as body mass index ≥30 kg/m2 with any metabolic disorders in blood pressure, blood glucose, and blood lipids. The age-adjusted percentage of MUO was calculated, and linear regression models estimated trends in MUO. Results: The weighted mean age of adults was 47.28 years; 51.02% were male, 74.64% were non-Hispanic White. The age-adjusted percentage of MUO continuously increased in adults across all subgroups during 1999–2018, although with different magnitudes (all P<0.05 for linear trend). Adults aged 45 to 64 years consistently had higher percentages of MUO from 1999–2000 (34.25%; 95% confidence interval [CI], 25.85% to 42.66%) to 2017–2018 (42.03%; 95% CI, 35.09% to 48.97%) than the other two age subgroups (P<0.05 for group differences). The age-adjusted percentage of MUO was the highest among non-Hispanic Blacks while the lowest among non-Hispanic Whites in most cycles. Adults with high-income levels generally had lower MUO percentages from 1999–2000 (22.63%; 95% CI, 17.00% to 28.26%) to 2017–2018 (32.36%; 95% CI, 23.87% to 40.85%) compared with the other two subgroups. Conclusion This study detected a continuous linear increasing trend in MUO among US adults from 1999 to 2018. The persistence of disparities by age, race/ethnicity, and income is a cause for concern. This calls for implementing evidence-based, structural, and effective MUO prevention programs.

BACKGROUND:Titanium implants are widely used in clinical practice because of their high strength and good biocompatibility.However,during implantation,bacterial infection and tissue damage environment produce a large number of reactive oxygen species,which can easily lead to delayed tissue healing and surgical failure.Consequently,the development of titanium implants with antimicrobial and antioxidant properties becomes paramount. OBJECTIVE:Considering the potent antimicrobial attributes of copper ions and the remarkable antioxidant qualities of polyphenols,we proposed the fabrication of polyphenol-mediated copper ion coatings on titanium surfaces.These coatings were subsequently assessed for their in vitro antimicrobial and antioxidant properties. METHODS:Nanostructures were generated on the titanium surface using the alkali thermal method.The titanium was immersed in a solution containing tannic acid and copper ions to achieve polyphenol-mediated copper ion coatings.The surface morphology and water contact angle were detected.The loading and release of copper ions were examined using atomic absorption spectroscopy.Staphylococcus aureus was inoculated on the surface of pure titanium sheet(blank group),alkali heat treated titanium sheet(control group),and polyphenol mediated copper ion modified titanium sheet(experimental group)to observe the bacterial survival status.Osteoblast precursor cells MC3T3-E1 were co-cultivated on the surface of three groups of titanium sheets to assess their antioxidant properties and bioactivity. RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the polyphenol-mediated copper ion modified titanium sheet had rod-like nanostructures and no cracks on the surface.The surface hydrophilicity of copper ion modified titanium sheet mediated by polyphenol was close to that of pure titanium sheet.Atomic absorption spectrometry results showed a 51%increase in the loading capacity of copper ions after polyphenol mediation,with a uniform release of copper ions.(2)The antibacterial rates of titanium sheets in the blank group,control group,and experimental group were 0%,21.65%,and 93.75%,respectively.The live/dead staining and CTC staining showed that the live bacteria on the surface of titanium plates in the blank group were the most,and the live bacteria on the surface of titanium plates in the experimental group were the least.(3)The results of live/dead staining and CCK-8 assay showed that the three groups of titanium sheets had good cytocompatibility,and the titanium sheets in the experimental group were more conducive to the proliferation of MC3T3-E1 cells.Active oxygen fluorescence probe detection exhibited that compared with the other two groups,the fluorescence intensity of active oxygen on the surface of the experimental group was significantly reduced.The results of alkaline phosphatase and alizarin red S staining showed that the osteogenic differentiation and extracellular matrix mineralization of MC3T3-E1 cells on the surface of titanium sheets in the experimental group were stronger than those in the other two groups.(4)These results show that the polyphenol-mediated copper ion coating has strong antibacterial and antioxidant properties and promotes osteogenic differentiation.

BackgroundNon-suicidal self-injury （NSSI） behavior among adolescents has become a global public health concern. Anxiety and depression are considered key factors influencing NSSI behavior， while social support may play a protective role in alleviating emotional and behavioral issues. However， existing research has primarily focused on the direct impact of individual factors on NSSI behavior， with insufficient exploration of the combined effects of anxiety， depression and social support. ObjectiveTo investigate the direct effect of anxiety on NSSI， the mediating role of depression and the moderating role of social support in relationship between anxiety and NSSI behavior， thus to provide references for the prevention and intervention of NSSI behavior among adolescents. MethodsIn February 2022， a total of 40 820 students in grades 7 to 12 across 10 middle schools in a district of Chengdu were selected as participants， and they were assessed using Generalized Anxiety Disorder Scale-7 item （GAD-7）， Patient's Health Questionnaire Depression Scale-9 item （PHQ-9）， Social Support Scale for Urban Students （SSSUS） and Adolescent Self-Harm Scale （ASHS）. Pearson correlation analysis was conducted to examine the correlations between scale scores among adolescents with NSSI behaviors. Mediation and moderation analyses were performed using Process 3.5 in SPSS， and the significance was tested with bootstrapping. The interaction was visualized by using simple slope analysis. ResultsAmong 34 534 （84.60%） valid respondents， 542 adolescents （1.57%） reported engaging in NSSI behavior. Significant differences in gender， GAD-7 scores， PHQ-9 scores， and SSSUS scores were observed between NSSI behavior group and non-NSSI group （χ²/t=62.889， 71.120， 94.365， -41.464， P<0.01）.Adolesents with NSSI showed positive correlations between GAD-7 scores and both ASHS and PHQ-9 scores （r=0.158， 0.166， P<0.01）. PHQ-9 scores were positively correlated with ASHS scores （r=0.364， P<0.01）， but negatively correlated with SSSUS scores （r=-0.290， P<0.01）. SSSUS scores were negatively correlated with ASHS scores （r=-0.247， P<0.01）. Depression partially mediated the relationship between anxiety and NSSI behavior， with an effect size of 0.544 （95% CI： 0.162~0.944）， accounting for 35.79% of the total effect. Social support moderated the relationship between depression and NSSI bahavior， with an effect value of -0.082 （95% CI： -0.135~-0.029）. ConclusionAnxiety not only directly influences NSSI bahavior among adolescents， also indirectly exacerbates it through depression， while social support mitigates the impact of depression on NSSI behavior. ［Funded by Youth Project of National Natural Science Foundation of China （number， 82401812）； Project of Health Commission of Sichuan Province （number， 24LCYJPT18）］

Objective To investigate the dosimetric differences in preoperative short-course volumetric modulated arc therapy(VMAT)for rectal cancer using different fluence smoothing(FS)levels in the Monaco Treatment Planning System(Monaco TPS).Methods Twenty rectal cancer patients who received preoperative neoadjuvant short-course VMAT at some hospital from September 2021 to December 2022 were retrospectively selected.Four groups of radiotherapy plans were formulated using the Monaco TPS for each case,which were classified into an off group,a low group,a medium group and a high group based on the FS levels.Then the four groups were compared in terms of the dosimetric parameters,monitor unit and number of the segments in the planning target volume(PTV)and organ at risk(OAR).Statistical analysis was performed using SPSS 27.0 software.Results All the four groups had the doses to the target volume meeting clinical requirements,which had no significant differences in the doses to 5％(D5％)and 95％(D95％)to the target volume and the maximum dose(Dmax),minimum dose(Dmin),mean dose(Dmean)and conformity index(all P＞0.05).Statistical differences were found between the homogeneity indexes of the four groups(P＜0.05),with the medium group behaving the best.The number of the segments rose while the mornitor units decreased siginificantly with the increase of FS levels,with the differences being statistically significant(P＜0.05).There were no significant differences between the V25,V20,V15 and V10 of the small intestine,the V25 and V20 of the bladder and the V15 and V10 of the left and right femur(all P＞0.05).Conclusion In preoperative short-course VMAT for rectal cancer,clinical requirements can be met with different FS levels in the Monaco TPS,and medium-level FS results in optimal overall dose distribution in terms of treatment planning.[Chinese Medical Equipment Journal,2025,46(5):48-53]