[摘 要] 目的：探讨环指蛋白8（RNF8）对子宫内膜癌（EC）细胞顺铂（CDDP）敏感性的影响及可能机制。方法：基于在线数据库分析RNF8在EC组织中的表达及拷贝数变异；采用慢病毒介导shRNA稳定敲低Ishikawa细胞中RNF8表达并进行CDDP处理，按sh-NC+溶剂对照、sh-RNF8+溶剂对照、sh-NC + CDDP、sh-RNF8 + CDDP分组处理，并设置sh-RNF8 + CDDP + KU60019抑制实验。采用CCK-8、克隆形成、Annexin V-FITC/PI流式细胞术、Hoechst 33258/PI染色、WB及γ-H2AX免疫荧光检测细胞活力、克隆形成、凋亡、DNA损伤累积及ATM/CHK2通路相关蛋白表达。结果：RNF8在EC组织和细胞中表达升高。RNF8敲低降低细胞存活率和IC50，抑制克隆形成，并进一步增强CDDP诱导的凋亡；同时BAX、Cleaved-Caspase-3和γ-H2AX表达升高，BCL-2、p-ATM、p-CHK2和RAD21表达降低。KU60019处理进一步促进DNA损伤累积和细胞凋亡，并降低细胞活力。结论：RNF8可能通过ATM/CHK2轴促进DNA损伤应答并降低EC细胞对CDDP的敏感性；敲低RNF8可增加DNA损伤累积并增强CDDP敏感性。

Objective: To evaluate the accuracy of body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR) in screening true obesity among children, so as to provide a scientific basis for precise screening and early prevention and control of childhood obesity. Methods: A total of 1 322 children aged 10-15 years old were surveyed by the Huantai Children Cardiovascular Health Cohort in 2021. Fat mass percentage (FMP) and fat mass index (FMI) were measured by bioelectrical impedance analysis, with FMP or FMI values at or above the age and sex-specific 70th percentiles as the criteria for defining true obesity. BMI, WC and WHtR were used to define general obesity and central obesity. The accuracy of these measures in screening for true obesity was evaluated by calculating the missed diagnosis rate, misdiagnosis rate, area under the curve(AUC) for receiver operating characteristic and Kappa coefficient. Results: Boys had higher BMI [(21.79±4.56) kg/m 2], WC [(76.41±12.53) cm] and WHtR (0.47±0.07) than girls [(20.83±4.13) kg/m 2, (70.69±10.06) cm, (0.45±0.06)] ( t =4.02, 9.19, 6.63), while boys had lower FMP [(18.29±8.35)%] and FMI [(4.35±2.79) kg/m 2] than girls [(24.87±6.51)%, (5.44±2.53) kg/m 2] ( t =-16.10,-7.42) ( P <0.01). Using FMP as a reference standard, the diagnosis error rates of screening for true obesity based on BMI, WC and WHtR were 12.24%, 2.11% and 2.11%, respectively; the diagnosis error rates were 10.88%, 27.28% and 24.33%; the AUC values were 0.88, 0.85 and 0.87; the Kappa coefficients were 0.67, 0.48 and 0.52. Using FMI as a reference standard, rates of BMI, WC and WHtR screening for true obesity were 14.20%, 1.23% and 2.78%; the diagnosis error rates were 4.81%, 20.84% and 18.14 %; the AUC values were 0.90, 0.89 and 0.90; the Kappa coefficients were 0.81, 0.64 and 0.67. Conclusions BMI has a higher diagnosis error rate in screening for true obesity in children, while WC and WHtR have higher diagnosis error rates. It is recommended to promote body fat assessment in clinical practice, so as to achieve more accurate prevention and control of chronic diseases.

Background The pathogenesis of silicosis has not been fully elucidated, and microRNAs (miRNA) may be involved in the occurrence and development of silicosis. Objective To investigate the effect of miR-204-3p inhibitor on the epithelial-mesenchymal transition (EMT) process and silicosis fibrosis in silicon dioxide dust-induced alveolar epithelial cells. Methods A co-culture model of macrophages and epithelial cells was established using a Transwell chamber. NR8383 macrophages were seeded into the upper chamber of the Transwell, and RLE-6TN cells were seeded into the lower chamber. After 24 h of culture, the medium in the lower chamber was discarded, washed three times with phosphate-buffered saline (PBS), and replaced with serum-free medium. The cells were divided into four groups: control group, silicosis group, miRNA NC group, and miR-204-3p inhibitor group. The lower chamber was transfected with miRNA NC for the miRNA NC group or the miR-204-3p inhibitor for the miR-204-3p inhibitor group. The lower chambers of the remaining two groups were added by equal amounts of serum-free medium. After 24 h, except for the control group that received an equal volume of serum-free medium, the upper chambers of the remaining three groups were treated with 800 μg·mL⁻¹ silicon dioxide dust. Morphological changes in each group were observed under a microscope. The mRNA and protein expression levels of EMT-related factors, including α-smooth muscle actin (α-SMA), Vimentin, N-Cadherin, and E-Cadherin, were detected by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) and Western blot. The mRNA and protein expression levels of fibrosis-related factors, including Collagen I, Collagen III, and Fibronectin, were also assessed by RT-qPCR and Western blot. The fluorescence expression intensities of α-SMA, N-Cadherin, and E-Cadherin were evaluated by immunofluorescence. Results The morphological observation revealed that RLE-6TN cells in the control group exhibited a regular oval shape. After treatment with silicon dioxide, the cells predominantly displayed a long spindle shape. Following the intervention with the miR-204-3p inhibitor, the number of long spindle-shaped cells increased, and the intercellular gaps widened. The RT-qPCR results showed that, compared with the control group, the silicosis group exhibited significantly higher relative mRNA expression levels of EMT-related markers (α-SMA, Vimentin, and N-Cadherin) (P<0.05), while the relative mRNA expression level of E-Cadherin was significantly reduced (P<0.05); the relative mRNA expression levels of fibrosis-related markers (Collagen I, Collagen III, and Fibronectin) were also significantly elevated (P<0.05). Compared with the miRNA NC group, the miR-204-3p inhibitor group showed significantly increased relative mRNA expression levels of α-SMA, Vimentin, and N-Cadherin (P<0.05), decreased E-Cadherin mPNA expression (P<0.05), and elevated mPNA expression of Collagen I, Collagen III, and Fibronectin (P<0.05). The Western blot analysis indicated that, compared with the control group, the silicosis group had significantly higher protein expression levels of α-SMA, Vimentin, and N-Cadherin (P<0.05), lower E-Cadherin protein expression (P<0.05), and increased protein expression of Collagen I, Collagen III, and Fibronectin (P<0.05). Compared with the miRNA NC group, the miR-204-3p inhibitor group exhibited significantly elevated protein expression levels of α-SMA, Vimentin, and N-Cadherin (P<0.05), reduced E-Cadherin expression (P<0.05), and increased protein expression of Collagen I, Collagen III, and Fibronectin (P<0.05). The immunofluorescence analysis demonstrated that, compared with the control group, the silicosis group showed enhanced fluorescence intensities of α-SMA and N-Cadherin and reduced fluorescence intensity of E-Cadherin. Compared with the miRNA NC group, the miR-204-3p inhibitor group exhibited increased fluorescence intensities of α-SMA and N-Cadherin and decreased fluorescence intensity of E-Cadherin. Conclusion The miR-204-3p inhibitor may exacerbate the EMT process and silicosis fibrosis in silicon dioxide-induced RLE-6TN cells. miR-204-3p plays a negative regulatory role in silicosis fibrosis.

Objective:To examine the manifestations and causes of administrative burden among primary healthcare professionals,and to explore its impact on job burnout through the mediating role of role conflict,providing theoretical and empirical support for governance-level burden-reduction strategies.Methods:An exploratory sequential mixed-methods design was employed,focusing on primary healthcare professionals in Shandong Province.In the first phase,in-depth interviews were conducted with 175 participants;in the second phase,a questionnaire survey of 1,096 participants and follow-up interviews with 107 participants were carried out.Results:The proportions of respondents who reported"heavy"or"very heavy"burdens were 62.7%for inspection,54.8%for documentation,51.8%for reporting,and 24.4%for meetings.Structural equation modeling showed that administrative burden had a direct effect on job burnout(0.150)and an indirect effect through role conflict(0.093).Qualitative findings further indicated that administrative burden largely stemmed from public health traceability requirements and medical insurance policies,and operated through both resource-based and value-based conflicts.Conclusions:Primary healthcare professionals face considerable administrative burdens,which may heighten job burnout through role conflict.Governance reforms should optimize inspection and assessment,streamline data reporting,refine record-keeping,and promote collaborative governance to break the chain of institutional pressure leading to burnout.

Objective To explore the role of miR-204-3p in silicosis and to elucidate the mechanism by which it affects silicosis fibers by regulating silica dust-induced alveolar epithelial-mesenchymal transition(EMT)in rats.Methods Forty SD rats were divided randomly into 4 groups:Control,Silicosis,AAV-Control,and AAV-miR-204-3p groups.The pathology of lung tissue damage was detected by hematoxylin and eosin(HE)and Masson staining.Relative expression levels of miR-204-3p and EMT marker genes in lung tissues from rats in each group were analyzed by real-time fluorescence reverse transcription quantitative PCR(RT-qPCR),and protein expression levels of EMT-related markers in lung tissues were detected by Western blot.Results The alveolar structure was damaged,the lung septa showed interstitial fibrosis,and expression levels of mesenchymal markers were elevated in the Silicosis group compared with the Control group(P＜0.05,P＜0.01,P＜0.001).The alveolar structure was more complete,the EMT process was alleviated,fibrosis was improved,and mesenchymal marker expression was reduced in the AAV-miR-204-3p group compared with the AAV-Control group(P＜0.05,P＜0.01,P＜0.001).Conclusions Free silica dust induces EMT in rat lung tissue.Overexpression of miR-204-3p can attenuate the EMT process induced by free silica dust in rats,and may thus affect silicosis fibrosis.

Objective:To examine the manifestations and causes of administrative burden among primary healthcare professionals,and to explore its impact on job burnout through the mediating role of role conflict,providing theoretical and empirical support for governance-level burden-reduction strategies.Methods:An exploratory sequential mixed-methods design was employed,focusing on primary healthcare professionals in Shandong Province.In the first phase,in-depth interviews were conducted with 175 participants;in the second phase,a questionnaire survey of 1,096 participants and follow-up interviews with 107 participants were carried out.Results:The proportions of respondents who reported"heavy"or"very heavy"burdens were 62.7%for inspection,54.8%for documentation,51.8%for reporting,and 24.4%for meetings.Structural equation modeling showed that administrative burden had a direct effect on job burnout(0.150)and an indirect effect through role conflict(0.093).Qualitative findings further indicated that administrative burden largely stemmed from public health traceability requirements and medical insurance policies,and operated through both resource-based and value-based conflicts.Conclusions:Primary healthcare professionals face considerable administrative burdens,which may heighten job burnout through role conflict.Governance reforms should optimize inspection and assessment,streamline data reporting,refine record-keeping,and promote collaborative governance to break the chain of institutional pressure leading to burnout.

Aim To compare the observation results of atomic force microscopy(AFM)and scanning electron microscopy(SEM),and to summarize the main problems and solutions of AFM in observing biological macromolecules,using the observa-tion subjects of protein samples purified by our research group.Methods The protein samples were diluted to 15 nmol·L-1 with PBS,fixed on glass slides,silicon wafers,and mica sheets,dried,and made into solid-phase observation samples.SEM sam-ples were plated with platinum before observation.The surface structures of proteins were observed using AFM and SEM,sample heights were calculated,and differences in results were com-pared.Results Protein samples with positive charges tended to shift to the right during observation due to the repulsion of the AFM probe;mica sheets could effectively eliminate the positive charge of proteins to avoid sample movement;PBS provided a stable environment for protein samples,but the crystallization of PBS salts interfered with probe operation and imaging clarity;SEM samples needed to be plated with platinum before observa-tion and could not achieve the precision of AFM.Conclusions Both AFM and SEM can directly observe protein structures in vitro,with AFM providing higher precision results;when protein sample stability permits,ultrapure water is preferred as the sol-vent carrier,and volatile liquids such as ethanol can also serve as solvent carriers.The application of AFM offers a new approach for pharmacological studies on interactions between biological macromolecules.

Aim To explore the mechanism of the syn-ergistic effect of the ferroptosis inducer erastin com-bined with shikonin in promoting ferroptosis in human hypertrophic scar fibroblasts(HSFBs).Methods Hypertrophic scar tissues provided by the General Hos-pital of Ningxia Medical University were collected,and HSFBs were extracted.HSFBs were identified by HE staining and immunofluorescence.The inhibitory rates of Era and SHK on HSFBs at different concentrations were detected by CCK-8 assay,and the IC50 value was calculated.CompuSyn software was used to calculate the co-use index(CI).Control group,Erastin(Era)group,shikonin(SHK)group and Era+SHK group were set up,and the number and morphological chan-ges of cells were observed after 24 hours of interven-tion.The ability of cell migration and invasion was de-tected by scratch test and Transwell test.The changes of malondialdehyde(MDA),total iron ion and reactive oxygen species(ROS)were detected by corresponding biochemical kits.The expressions of collagen I,α-SMA and GOT1,SLC7A11,GPX4 and FTH1 were detected by Western blot.Results The IC50 value of Era and SHK of primary HSFBs was 2.22 μmol·L-1 and 3.94μmol·L-1 respectively,which was used as the single drug concentration for subsequent experiments.The CompuSyn software was employed to calculate the CI value when the two drugs were used in combination,and the concentrations corresponding to CI=0.39597(Era:1.2 μmol·L-1+SHK:1.5 μmol·L-1)were selected as subsequent combination concentrations(Because when CI was equal to 0.395 97,the concen-tration of each drug was lower than the concentration of single drug,and the inhibition rate of combined drug was greater than 50％).Compared with the monother-apy group,the number of HSFBs in the SHK+Era group was significantly reduced,cell membrane showed breakage and vesiculation,cell wrinkling became smal-ler,and cytoplasm was concentrated.The migration and invasion ability of HSFBs in the SHK+Era group were obviously weakened(P＜0.05),and the expres-sion of fibrosis-related proteins collagen Ⅰ and α-SMA was reduced(P＜0.05);the contents of MDA,total i-ron ions,and ROS in HSFBs of the SHK+Era group increased(P＜0.05),and the protein expression lev-els of SLC7A11,GOT1,GPX4,and FTH1 further de-creased(P＜0.05).Conclusions Erastin in combi-nation with shikonin can synergistically inhibit the pro-liferation,migration and fibrosis levels of HSFBs.The mechanism may be that erastin enhances the inhibition of shikotin on GOT1,increases the levels of cellular i-ron ions,ROS,and lipid peroxides,thereby promoting ferroptosis in HSFBs.

Aim To study the possibility of luteolin(LUT)as a new drug of traditional Chinese medicine and its improving effect on glucose and lipid metabo-lism and liver oxidative stress injury in db/db mice,and to explore the possible mechanism.Methods AI was used to predict the drug toxicity,evaluate the phys-ical and chemical properties and segment the molecular structure of LUT.Molecular docking was used to verify the binding ability of LUT with Nrf2 and HMOX1;db/m mice were divided into the group C,and db/db mice were randomly divided into the T,L,M,H and P groups.The body weight and FBG changes were ob-served within 12 weeks of intervention.The expres-sions of FBG,HbA1c,Fins,TC,TG,HDL-C,LDL-C were detected.The pathomorphological changes and steatosis of mouse liver were observed by HE and oil red O staining.The expression of MDA,SOD and GSH-Px in liver was detected by Kit.The protein and mRNA expressions of Nrf2 and HMOX1 were detected by immunohistochemistry,WB and qPCR.Results AI algorithm predicted the safety and easy synthesis of LUT.LUT intervention had no significant effect on the body weight of db/db mice.After 12 weeks,compared with the group C,the livers of mice in group T showed disordered structure of hepatic lobules,irregular ar-rangement of hepatocytes,and a large number of fat vacuoles and lipid droplets in the cytoplasm.Compared with the group T,LUT intervention could improve the pathological changes of liver,reduce the expression of FBG,HbA1c,fins,TC,TG,LDL-C,MDA,improve the level of HOMA-IR,and upregulate the activities of SOD and GSH-Px.Molecular docking results showed LUT had strong binding with Nrf2 and HMOX1,and could increase the expression of Nrf2 and HMOX1.Conclu-sion LUT can correct the disorder of glucose and lip-id metabolism in db/db mice,and improve the level of oxidative stress in liver of mice through Nrf2/HMOX1 pathway,which has the development prospect as a new Chinese medicine for the treatment of T2DM.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.