Objective To evaluate the radiation dose levels induced by secondary neutrons at different locations inside proton therapy treatment rooms, and analyze the distribution characteristics of neutron energy spectra by combining experimental measurements with simulations, and to provide a theoretical basis and technical support for radiation protection design and management in proton therapy. Methods Multiple representative measurement points were established in the treatment rooms of two hospital-based proton therapy centers. The DIAMON neutron spectrometer was employed to perform in-situ measurements of secondary neutron doses and energy spectra. Three-dimensional simulation models of treatment rooms were constructed using the FLUKA code to simulate the generation and transport of secondary neutrons. Results Measurements showed that the neutron dose was highest near the target region, reaching up to 4293.750 µSv/h. The doses at the maze entrance were the next highest, ranging from 422.091 to 489.268 µSv/h, while the doses in the middle section of the maze ranged from 2.860 to 6.727 µSv/h. The neutron energy spectra exhibited a triple-peak pattern. Conclusion Significant accumulation of secondary neutrons was observed near the target and in the maze regions during proton therapy, with intermediate-energy neutrons being the dominant dose contributor. The consistency between measurements and simulations validated the reliability of the model, which can provide a basis for optimizing treatment room shielding and controlling occupational exposure for staff.

Radiotherapy is a cornerstone in the treatment of malignant tumors. It induces DNA damage through high-energy radiation, preferentially eliminating rapidly proliferating tumor cells. However, its clinical efficacy is often limited by tumor radioresistance and collateral damage to normal tissues. Consequently, elucidating the cellular response mechanisms to radiation stress and identifying key targets that can both sensitize tumor cells and protect normal tissues have become critical strategies for improving radiotherapy outcomes. Radiation stress triggers structural remodeling of the nucleolus, leading to the dissociation of certain ribosomal proteins from the ribosome and enabling them to acquire extra-ribosomal functions. Among these, RPL11 can be released and specifically binds to MDM2, thus inhibiting its E3 ubiquitin ligase activity, stabilizing p53, and mediating cell cycle arrest and apoptosis. The RPL11-MDM2-p53 pathway, acting as a signaling hub that links nucleolar dysfunction to cell fate determination, plays a pivotal role in maintaining genomic stability and regulating cellular responses to radiation. This review first introduces the basic characteristics of RPL11 and elucidates the molecular basis of radiation-induced ribosomal stress. It then outlines the core regulatory mechanisms of the cell cycle. On this basis, it focuses on the mechanisms by which radiation-induced RPL11 regulates the cell cycle and analyzes the specific effects of RPL11 on cell cycle. Furthermore, it discusses the role of the RPL11-MDM2-p53 pathway in cell cycle regulation. Finally, it explores the role of this pathway in maintaining genomic stability and determining cell fate, and highlights its potential value as a target for radiosensitization, aiming to provide new perspectives for enhancing tumor radiosensitivity and reducing damage to normal tissues.

Radiotherapy is a cornerstone in the treatment of malignant tumors. It induces DNA damage through high-energy radiation, preferentially eliminating rapidly proliferating tumor cells. However, its clinical efficacy is often limited by tumor radioresistance and collateral damage to normal tissues. Consequently, elucidating the cellular response mechanisms to radiation stress and identifying key targets that can both sensitize tumor cells and protect normal tissues have become critical strategies for improving radiotherapy outcomes. Radiation stress triggers structural remodeling of the nucleolus, leading to the dissociation of certain ribosomal proteins from the ribosome and enabling them to acquire extra-ribosomal functions. Among these, RPL11 can be released and specifically binds to MDM2, thus inhibiting its E3 ubiquitin ligase activity, stabilizing p53, and mediating cell cycle arrest and apoptosis. The RPL11-MDM2-p53 pathway, acting as a signaling hub that links nucleolar dysfunction to cell fate determination, plays a pivotal role in maintaining genomic stability and regulating cellular responses to radiation. This review first introduces the basic characteristics of RPL11 and elucidates the molecular basis of radiation-induced ribosomal stress. It then outlines the core regulatory mechanisms of the cell cycle. On this basis, it focuses on the mechanisms by which radiation-induced RPL11 regulates the cell cycle and analyzes the specific effects of RPL11 on cell cycle. Furthermore, it discusses the role of the RPL11-MDM2-p53 pathway in cell cycle regulation. Finally, it explores the role of this pathway in maintaining genomic stability and determining cell fate, and highlights its potential value as a target for radiosensitization, aiming to provide new perspectives for enhancing tumor radiosensitivity and reducing damage to normal tissues.

Radiotherapy is a cornerstone in the treatment of malignant tumors. It induces DNA damage through high-energy radiation, preferentially eliminating rapidly proliferating tumor cells. However, its clinical efficacy is often limited by tumor radioresistance and collateral damage to normal tissues. Consequently, elucidating the cellular response mechanisms to radiation stress and identifying key targets that can both sensitize tumor cells and protect normal tissues have become critical strategies for improving radiotherapy outcomes. Radiation stress triggers structural remodeling of the nucleolus, leading to the dissociation of certain ribosomal proteins from the ribosome and enabling them to acquire extra-ribosomal functions. Among these, RPL11 can be released and specifically binds to MDM2, thus inhibiting its E3 ubiquitin ligase activity, stabilizing p53, and mediating cell cycle arrest and apoptosis. The RPL11-MDM2-p53 pathway, acting as a signaling hub that links nucleolar dysfunction to cell fate determination, plays a pivotal role in maintaining genomic stability and regulating cellular responses to radiation. This review first introduces the basic characteristics of RPL11 and elucidates the molecular basis of radiation-induced ribosomal stress. It then outlines the core regulatory mechanisms of the cell cycle. On this basis, it focuses on the mechanisms by which radiation-induced RPL11 regulates the cell cycle and analyzes the specific effects of RPL11 on cell cycle. Furthermore, it discusses the role of the RPL11-MDM2-p53 pathway in cell cycle regulation. Finally, it explores the role of this pathway in maintaining genomic stability and determining cell fate, and highlights its potential value as a target for radiosensitization, aiming to provide new perspectives for enhancing tumor radiosensitivity and reducing damage to normal tissues.

ObjectiveTo investigate the regulatory effect of icariin （ICA） on transforming growth factor-β₁ （TGF-β₁）/Smad pathway in bone microvascular endothelial cells （BMECs） and the effect on autophagy in BMECs. MethodsBMECs were isolated and cultured， and the cell types were identified by immunofluorescence. Cells were divided into the control group， model group （0.1 g·L^-1 methyl prednisolone）， ICA group （0.1 g·L^-1 methyl prednisolone +1×10^-5 mol·L^-1 ICA）， and TGF-β inhibitor group （0.1 g·L^-1 methyl prednisolone +1×10^-5 mol·L^-1 ICA +1×10^-5 mol·L^-1 LY2157299）. Transmission electron microscopy was used to observe the ultrastructure and autophagosome number of BMECs. Autophagy double-standard adenovirus was used to monitor the confocal autophagy flow generation of each cell. Real-time quantitative polymerase chain reaction （Real-time PCR） and Western blot were used to detect the gene and protein expression of autophagy in the TGF-β₁/ Smad pathway. ResultsAfter cell separation culture， platelet endothelial cell adhesion molecule （CD31） and von willebrand factor （vWF） immunofluorescence identified BMECs. Transmission electron microscopy showed that the cell membrane was damaged， and the nucleus was pyknotic and broken in the model group. Compared with the model group， the ICA group had complete cell membranes， clear structures， with autophagy-lysosome sparsely distributed. The confocal photo showed that BMECs had autophagosomes and autophagy-lysosomes， and the autophagy expression of the ICA group was similar to that of the blank group. Compared with the blank group， in the model group and the LY2157299 group， autophagosomes and autophagy-lysosomes were barely seen in the autophagy flow. Compared with the blank group， the mRNA and protein expressions of autophagy effector protein 1 （Beclin1） and microtubule-associated protein 1 light chain 3B （LC3B） in the model group were significantly decreased （P<0.01）， and those of ubiquitin-binding protein （p62） were significantly increased （P<0.01）. The mRNA expression of TGF-β₁， Smad homolog 2 （Smad2）， and Smad homolog 3 （Smad3） decreased （P<0.05， P<0.01）. The protein expressions of TGF-β₁， p-Smad2， and p-Smad3 were significantly decreased （P<0.01）. Compared with those of the model group， the mRNA and protein expression of Beclin1 and LC3B in BMECs of the ICA group increased （P<0.01）， and those of p62 significantly reduced （P<0.01）. The mRNA expression of TGF-β₁， Smad2， and Smad3 increased significantly （P<0.01）. The protein expression of TGF-β₁， p-Smad2， and p-Smad3 increased significantly （P<0.01）. Compared with those in the model group， the mRNA and protein expressions of Beclin1， LC3B， and p62 in the inhibitor group were not statistically significant. The expression of key genes and proteins of the TGF-β₁ pathway in the inhibitor group was not statistically significant. ConclusionICA can promote glucocorticoid-induced autophagy expression of BMECs， and its mechanism may be related to activating the TGF-β₁/Smad signaling pathway.

ObjectiveTo investigate the effect of icariin （ICA） on steroid-induced ferroptosis in bone microvascular endothelial cells （BMECs）. MethodsRat BMECs were selected and treated with 500 mg·L^-1 hydrocortisone for 1.5 h to establish a ferroptosis model of BMECs. The experimental cells were divided into a blank group， hormone group （500 mg·L^-1 hydrocortisone）， ICA group （500 mg·L^-1 hydrocortisone + 34 mg·L^-1 ICA）， and ferroptosis agonist group （500 mg·L^-1 hydrocortisone + 34 mg·L^-1 ICA + 2.7 mg·L^-1 erastin）. Cell viability was detected by CCK-8. The levels of ferrous ion， glutathione （GSH）， malondialdehyde （MDA）， superoxide dismutase （SOD）， and reactive oxygen species （ROS） were detected by related kit species. The ferroptosis-related proteins， such as glutathione peroxidase 4（GPX4）， ferritin light chain （FTL）， and transferrin receptor protein1 （sTfR） were detected by Western blot， as well as autophagy-related proteins including microtubule-associated protein 1 light chain 3B （LC3B）， Beclin1， B-cell lymphoma-2 （Bcl-2）， and Caspase-3. Results500 mg·L^-1 hydrocortisone intervention for 1.5 h could effectively induce ferroptosis in BMECs， and ferroptosis levels could reach a peak as the intervention continued. In terms of cellular antioxidant capacity， compared with those in the blank group， the cell vitality， GSH in the hormone group decreased significantly， and the levels of ROS， SOD， MDA， and ferrous ions were significantly increased （P<0.01）. Compared with those in the hormone group， the cell viability， GSH were significantly increased， and the levels of ROS， SOD， MDA， and ferrous ions were decreased in the ICA group （P<0.01）. Compared with those in the ICA group， the cell vitality， GSH in the ferroptosis agonist group decreased significantly， and the levels of ROS， SOD， MDA， and ferrous ions increased significantly （P<0.01）. In terms of the relationship between ferroptosis and autophagy， compared with the blank group， the hormone group had significantly increased expression levels of LC3B， sTfR， Beclin1， and FTL and significantly decreased expression levels of GPX4 （P<0.01）. Compared with the hormone group， The ICA group had significantly decreased expression levels of LC3B， sTfR， and FTL and significantly increased expression levels of Beclin 1 and GPX4 （P<0.01）. Compared with those in the ICA group， the expression levels of LC3B， sTfR， and FTL increased in the rapamycin group， and those of Beclin 1 and GPX4 decreased （P<0.01）. In terms of cell ferroptosis and apoptosis，compared with the blank group， the hormone group had significantly increased expression levels of FTL， sTfR and Caspase-3 and significantly decreased expression levels of GPX4， and Bcl-2 （P<0.01）. Compared with the hormone group， the ICA group had significantly decreased expression levels of FTL， sTfR and Caspase-3 and significantly increased expression levels of GPX4， and Bcl-2 （P<0.01）. Compared with those in the ICA group， the expression levels of FTL， sTfR and Caspase-3 in the ferroptosis agonist group were increased， and the expression levels of GPX4， and Bcl-2 were decreased （P<0.01）. In terms of cell function，compared with that in the blank group， the ability of cell migration and tube formation was significantly decreased in the hormone group （P<0.01）. Compared with that in the hormone group， the cell migration and tube formation ability in the ICA group were significantly increased （P<0.01）. ConclusionFerroptosis is involved in steroid-induced damage in BMECs. ICA can inhibit steroid-induced ferroptosis in BMECs， and the mechanism may be associated with the inhibition of ferroptosis by regulating autophagy.

Steroid-induced osteonecrosis of the femoral head （SONFH） is a severe musculoskeletal disorder often induced by the prolonged or excessive use of glucocorticoids. Characterized by ischemia of bone cells， necrosis， and trabecular fractures， SONFH is accompanied by pain， femoral head collapse， and joint dysfunction， which can lead to disability in severe cases. The pathogenesis of SONFH involves hormone-induced osteoblast apoptosis， bone microvascular endothelial cell （BMEC） apoptosis， oxidative stress， and inflammatory responses. The phosphatidylinositol 3-kinase/protein kinase B （PI3K/Akt） signaling pathway plays a pivotal role in the development of the disease. Modulating the PI3K/Akt signaling pathway can promote Akt phosphorylation， thereby stimulating the osteogenic differentiation of bone marrow mesenchymal stem cells and osteoblasts， promoting angiogenesis in BMECs， and inhibiting osteoclastogenesis. The research on the treatment of SONFH with traditional Chinese medicine （TCM） has gained increasing attention. Recent studies have shown that TCM monomers and compounds have potential therapeutic effect on SONFH by intervening in the PI3K/Akt signaling pathway. These studies not only provide a scientific basis for the application of TCM in the treatment of SONFH but also offer new ideas for the development of new therapeutic strategies. This review summarized the progress in Chinese and international research on the PI3K/Akt signaling pathway in SONFH over the past five years. It involved the composition and transmission mechanisms of the signaling pathway， as well as its regulatory effects on osteoblasts， mesenchymal stem cells， osteoclasts， BMECs， and other cells. Additionally， the review explored the TCM understanding of SONFH and the application of TCM monomers and compounds in the intervention of the PI3K/Akt pathway. By systematically analyzing and organizing these research findings， this article aimed to provide references and point out directions for the clinical prevention and treatment of SONFH and promote further development of TCM in this field. With in-depth research on the PI3K/Akt pathway and the modern application of TCM， it is expected to bring safer and more effective treatment options for patients with SONFH.

Pre-admission is a critical initiative to optimize medical service processes and alleviate the challenge of "difficult access to healthcare. "However, there is currently a lack of standardized protocols for pre-admission procedures. This study aims to systematically analyze key nodes and risk factors in pre-admission process design and propose optimization strategies, providing a foundation for policy formulation and hospital practices. By constructing a "forward-reverse" dual-process model of pre-admission and identifying risk points based on stakeholder theory (patients, hospitals, healthcare administration, and insurance), the study reveals that while pre-admission can reduce the average length of stay, improve bed turnover rates, and enhance patient satisfaction, it also presents risks such as cross-period financial settlement, challenges in insurance policy adaptability, demands for information system integration, and the need for defining medical safety boundaries. To optimize the pre-admission process and mitigate these risks, this study explores framework improvements in areas including eligibility criteria, mode selection, cost settlement, transition between pre-admission and inpatient status, and cancellation of pre-admission, offering practical guidance for public hospitals. The authors argue that pre-admission requires tripartite collaboration among hospitals, insurers, and healthcare administrations: hospitals should establish top-level design, continuously refine processes, and implement dynamic risk assessment mechanisms; insurance providers should support cross-period settlement policies; and healthcare administrations should issue guiding policies or standardized protocols. Through multi-department coordination and collaborative efforts, the optimization and innovation of pre-admission processes can be advanced, ultimately delivering more efficient and convenient healthcare experiences for patients.

OBJECTIVE: To explore the effectiveness of free paraumbilical perforator flaps in repairing skin and soft tissue defects in children. METHODS: Between February 2018 and March 2024, 12 children with skin and soft tissue defects were treated with the free paraumbilical perforator flaps. There were 7 boys and 5 girls with an average age of 6.3 years (range, 2-12 years). The defects located on the upper limbs in 6 cases, lower limbs in 5 cases, and neck in 1 case. The causes of wounds included 7 cases of electrical burns, 1 case of thermal burn, 2 cases of scar release and excision due to scar contraction after burns, 1 case of scar ulcer at the amputation stump after severe burns, and 1 case of skin necrosis after a traffic accident injury. The size of defects after debridement ranged from 7.0 cm×4.0 cm to 18.0 cm×10.0 cm. According to the defect size, 11 cases were repaired with unilateral paraumbilical perforator flaps centered on the umbilicus, among which 3 cases with larger defects were designed as "L"-shaped flaps along the lateral and lower ends of the perforator; the donor sites were directly closed. One case with extensive defect after scar excision and release was repaired with bilateral expanded paraumbilical perforator flaps; the donor sites were repaired with autologous split-thickness skin grafts. The size of flaps ranged from 9.0 cm×4.0 cm to 20.0 cm×11.0 cm. Postoperatively, analgesia and sedation were provided, and the blood supply of the flaps was observed. RESULTS: All operations were successfully completed. The operation time was 4-7 hours, with an average of 5.0 hours. After postoperative analgesia and sedation, the visual analogue scale (VAS) score for pain in all children was less than or equal to 3, and there was no non-cooperation due to pain. All flaps and skin grafts survived completely, and the wounds healed by first intention. Ten children underwent 1-4 times of flap de-fatting, finger separation, and trimming. All children were followed up 6-48 months (mean, 26.6 months). No obvious swelling of the flaps occurred, and the texture was soft. At last follow-up, among the 6 children with upper limb defects, 2 had upper limb function grade Ⅳ and 4 had upper limb function grade Ⅴ according to the Carroll upper limb function assessment method. The 4 children with lower limb defects had no limitation of joint movement. The neck flexion and rotation in the 1 child with neck defect significantly improved when compared with that before operation. The 1 child with residual ulcer at the amputation stump could wear a prosthesis and move without limitation, and no new ulcer occurred. Linear scars were left at the donor sites, and no abdominal wall hernia was formed. CONCLUSION The free paraumbilical perforator flap has abundant blood supply and can be harvested in large size. It can be used to repair skin and soft tissue defects in children and has the advantages of short operation time, minimal injury, high safety, and minimal impact on the growth and development of children.
Humans ; Perforator Flap/transplantation* ; Child ; Male ; Female ; Soft Tissue Injuries/surgery* ; Child, Preschool ; Plastic Surgery Procedures/methods* ; Burns/surgery* ; Umbilicus/surgery* ; Skin Transplantation/methods* ; Skin/injuries* ; Cicatrix/surgery* ; Treatment Outcome

Objective To investigate the association between the variability of remnant cholesterol inflammatory index(RCII),a novel composite biomarker,and the risk of stroke,in order to provide a theoretical basis for stroke prevention.Methods A prospective cohort study was conducted on 38 659 Kailuan individuals who took annual physical examinations in 2006,2008,and 2010.These subjects were grouped based on the quartiles of RCII variability,which was represented by standard deviation(SD)and average real variability(ARV),and were followed up every 2 years,with the occurrence of stroke(including ischemic and hemorrhagic strokes),death,or the end of follow-up on December 31,2022 as the endpoints.Kaplan-Meier method was used to calculate the cumulative incidence rate of endpoint events across different groups,and log-rank test was used to compare the difference of cumulative incidence of endpoint events in each group.Multivariate Cox proportional hazards regression model was adopted to analyze the association between RCII variability and risk of stroke.Results Among the 38 659 participants,a total of 2 539 strokes occurred during a mean follow-up period of 11.22±2.26 years.After adjusting confounding factors,when the participants were grouped by the quartiles of RCII-SD,the hazard ratio(HR)for stroke was 1.034(95%CI:0.917～1.167,P=0.584),1.146(95%CI:1.018～1.290,P=0.025),and 1.209(95%CI:1.066～1.370,P=0.003),respectively in the Q2,Q3,and Q4 groups,when compared with the Q1 group(Ptrend<0.05).When they were grouped by the quartiles of RCII-ARV,the HR for stroke was 1.008(95%CI:0.894～1.136,P=0.901),1.109(95%CI:0.986～1.248,P=0.085),and 1.152(95%CI:1.018～1.303,P=0.025),respectively,in the Q2,Q3,and Q4 groups,when compared with the Q1 group.Furthermore,both sensitivity and stratified analyses yielded similar results.Conclusion RCII variability is significantly associated with stroke,and the risk of stroke is gradually increasing with increment of the variability.Countermeasures Relevant authorities can focus on reducing RCII variability as a central objective by establishing regular monitoring mechanism,strengthening lifestyle interventions,and standardizing dietary,exercise,and weight management in order to suppress the index fluctuations.The principle of stable lipid-lowering in medication and optimization of therapeutic regimens with stable efficacy should be emphasized to prevent the risk of additional vascular damage.