Methods: Six finite element models of T12 burst fractures were developed to simulate short-segment stabilization under normal or osteoporotic bone conditions, with/without augmentation screws at the fractured vertebra. Spinal stiffness, implant stresses, and axial displacement/micromotion of the bony defect were measured and compared under mechanical loading. Results: Osteoporotic models exhibited a greater range of motion (ROM) than normal bone. All six-screw constructs reduced ROM across all motions compared with traditional four-screw models. Osteoporotic fracture models gained greater benefit from intermediate screw augmentation at the fracture vertebra, which also lowered axial displacement/micromotion. In six-screw models, rod stress increased while pedicle screw stress decreased. Intermediate screws at fractured vertebrae produced similar changes in stress distribution across all fixation models, regardless of bone quality. Conclusions Our findings may facilitate implant selection for osteoporotic burst fractures, supporting the use of more rigid fixation sixscrew constructs to reduce the risk of mechanical failure and postoperative re-collapse.

BACKGROUND:Allogeneic hematopoietic stem cell transplantation is currently the most effective method for the radical treatment of thalassemia major,but only half of patients can find compatible bone marrow or peripheral blood stem cells.Sib-derived umbilical cord blood stem cells have different characteristics from bone marrow and peripheral blood stem cells,and are a potential alternative source of hematopoietic stem cells for transplantation in patients with thalassemia major.OBJECTIVE:To investigate the therapeutic effect of human leukocyte antigen matched sibling fresh umbilical cord blood transplantation in the treatment of β-thalassemia major in children.METHODS:Forty-eight children with β-thalassemia major,including 28 males and 20 females,with a median age of 4 years old,were selected from Nanfang Hospital of Southern Medical University from June 2010 to June 2020.All of them received fresh cord blood transplantation from human leukocyte antigen matched sibling.Transplantation conditioning adopted a myeloablative regiment without anti-thymocyte globulin.A combination of cyclosporine A and mycophenolate mofetil with or without short-range methotrexate was administered for graft-versus-host disease.RESULTS AND CONCLUSION:(1)The median infused doses of total nucleated cells and CD34+cells were 8.17×107/kg and 2.40×105/kg,respectively in 48 children.The median follow-up time after cord blood transplantation was 98 months,and 44 cases were successfully engrafted.The median time to neutrophil and platelet engraftment was 28 and 31 days,respectively.Among them,37 cases were found to be donor-type complete chimerism detected as evidence of implantation after transplantation,7 cases were found to be stable mixed chimerism.(2)Among the 44 children with successful implantation,four patients developed acute graft-versus-host disease,and were scored as grade Ⅰ(n=2)and grade Ⅱ(n=2).All the affected organs were skin,and no chronic graft-versus-host disease occurred.(3)After umbilical cord blood transplantation,cytomegalovirus infection and activation occurred in 5 of the 48 cases,sepsis in 12 cases,invasive fungal disease in 3 cases,stomatitis in 21 cases,hemorrhagic cystitis in 8 cases,and hepatic vein occlusion in 1 case.(4)Among 48 children,47 patients survived;1 died of severe pneumonia combined with acute heart failure 28 days after transplantation;43 survived without disease;3 had primary implantation failure,and 1 had pancytopenia after transplantation.The 5-year probabilities of overall survival and disease-free survival were 98％and 89％,respectively.The cumulative incidence of transplant-related deaths at 1 year was 2.1％.(5)The above results indicate that human leukocyte antigen matched sibling fresh umbilical cord blood transplantation is effective in the treatment of β-thalassemia major in children with a low incidence of graft-versus-host disease.

End-tidal carbon dioxide monitoring is an important means of evaluating human lung function and is widely used in fields such as clinical emergency treatment and cardiopulmonary resuscitation. This paper develops a microstream end-tidal carbon dioxide monitoring system. It adopts an integrated gas circuit design to further reduce the size of the equipment. The system uses the method of calculating the root mean square (RMS) of differential pressure signals to regulate the gas circuit flow, enabling the system to stably operate at a flow state of 30 mL/min. In addition, by simultaneously detecting multiple environmental parameters such as temperature and pressure, the system realizes system state monitoring and gas parameter compensation. The test results show that various indicators of the system meet the requirements of relevant standards, laying a good foundation for subsequent engineering applications.
Carbon Dioxide/analysis* ; Equipment Design ; Monitoring, Physiologic/methods* ; Humans

Objective To investigate the effect of tirofiban combined with oxiracetam on acute anterior circulation progressive cerebral infarction.Methods A total of 171 patients with acute anteri-or circulation progressive cerebral infarction from October 2022 to January 2024 were enrolled and ran-domly divided into three groups using a random number table.The control group of 57 patients re-ceived conventional treatment,the observation group A received tirofiban in addition to conventional treatment,and the observation group B received oxiracetam on the basis of observation group A's treat-ment.The effectiveness indicators[including the rates of neurological improvement and neurological deterioration at 14 days after treatment,the rate of good prognosis and modified Rankin Scale(MRS)scores at 90 days after treatment,as well as the National Institutes of Health Stroke Scale(NIHSS)scores at 7 and 14 days after treatment and their differences from baseline],cognitive function[as-sessed using the Montreal Cognitive Assessment(MOCA)],and safety indicators(incidence rates of symptomatic intracranial hemorrhage,fatal intracranial hemorrhage,and mortality at 90 days after treat-ment)were compared among the three groups.Results There were no statistically significant differ-ences in the rates of neurological improvement and neurological deterioration at 14 days after treatment,the rate of good prognosis,and MRS scores at 90 days after treatment among the three groups(P＞0.05).There were statistically significant differences in NIHSS scores between baseline and 7 and 14 days after treatment in all three groups(P＜0.05),and the differences in NIHSS scores from baseline at the above time points were higher in observation group B than in observation group A and the control group(P＜0.05).There were no statistically significant differences in MOCA scores among the three groups before treatment(P＞0.05);however,the MOCA scores in the observation group B were higher than those in observation group A and the control group at 14,30,and 90 days after treatment(P＜0.05).There were no statistically significant differences in the incidence rates of symptomatic intracranial hemorrhage,fatal intracranial hemorrhage,and mortality at 90 days after treatment among the three groups(P＞0.05).Conclusion Tirofiban combined with oxiracetam can improve cognitive function in patients with acute anterior circulation progressive cerebral infarc-tion without increasing the risk of hemorrhage,and has better prognosis.

Objective:To deeply analyze the epidemiological characteristics and changing trends of intestinal infectious diseases in China, and provide scientific evidence for the prevention and control of intestinal infectious diseases.Methods:The incidence data of notifiable intestinal infectious diseases in China from 2013 to 2022 were collected from China Disease Prevention and Control Information System. Descriptive statistical method was used to analyze the distributions of intestinal infectious diseases in China, and the annual change rate and seasonal index were calculated.Results:During 2013-2022, intestinal infectious diseases were reported nationwide, with the cases accounting for 43.50% of all notifiable infectious disease cases. The average reported incidence rate was 224.50/100 000, showing a decreasing trend year by year (average annual percent change=-6.45%, t=-2.76, P=0.025). The top 5 intestinal infectious diseases were hand foot and mouth disease (HFMD) (130.40/100 000), other infectious diarrhea (80.18/100 000), dysentery (7.45/100 000), acute hemorrhagic conjunctivitis (2.49/100 000) and viral hepatitis E (1.92/100 000). The incidences of dysentery, HFMD, typhoid fever/paratyphoid fever, viral hepatitis A and acute hemorrhagic conjunctivitis all showed decreasing trends year by year (all P<0.05), while the incidences of hepatitis E and other infectious diarrhea showed no significant changes with year (both P>0.05). The incidence of intestinal infectious diseases was high during May to October, with the peak in June. The incidence rate of intestinal infectious diseases was significantly higher in men than in women (all P<0.05). The HFMD, other infectious diarrhea and dysentery cases were mainly children aged 0-5 years, while the cholera, hepatitis A, hepatitis E, typhoid fever/paratyphoid fever and acute hemorrhagic conjunctivitis cases were mainly farmers aged ≥20 years. The annual reported incidence rate of intestinal infectious diseases was higher in southern provinces (283.66/100 000) than in northern provinces (142.63/100 000), and the annual reported incidence rate of intestinal infectious diseases was higher in coastal provinces (279.52/100 000) than in inland provinces (181.78/100 000), the differences were all significant (both P<0.001). Conclusions:During 2013-2022, the incidence of intestinal infectious diseases decreased significantly in China, with HFMD and other infectious diarrhea as the main diseases. Strengthened surveillance for intestinal infectious diseases should be carried out in key groups, such as children living scatteredly and farmers, and targeted prevention and control measures should be taken according to the epidemiological characteristics of different diseases to effectively reduce the incidence of intestinal infectious diseases.

Over the past 40 years,prenatal ultrasound in China has undergone a transformative evolution,from basic grayscale imaging to the integration of artificial intelligence(AI).Initial efforts focused on identifying major fetal anomalies and establishing standardized screening systems.In subsequent decades,advances such as 3D/4D imaging,quantitative diagnostic models and multimodal approaches enhanced the accuracy and scope of assessments.Recently,the emergence of AI-driven diagnostics,early trimester screening and multi-omics integration have ushered Chinese prenatal ultrasound into an era of precision and intelligence.Chinese scholars have not only adopted global innovations,but also contributed original,locally adapted solutions and multidisciplinary frameworks.Looking ahead,future development will emphasize intelligent assistance,equitable access,evidence-based systems,and cross-disciplinary integration-driving continued improvement in birth defect prevention and maternal-fetal health.

Objective To investigate the ameliorative effect of deferoxamine(DFO)on cognitive impairment in a rat model of type 1 diabetes mellitus(T1DM)and to elucidate the molecular mechanisms underlying cerebral iron overload in T1DM rats.Methods Thirty-six healthy male SD rats(weighing 180～250 g)were randomly assigned into a blank control group(Ctrl),a T1DM model group and a DFO group,with 12 rats in each group.A single dose of 65 mg/kg streptozotocin(STZ)was intraperitoneally injected to the rats to establish a T1DM model,and those with fasting blood glucose≥16.7 mmol/L at 3 d later were designated as the T1DM group.Intracerebroventricular administration of DFO(5 μg/kg·d)was given to the DFO group for 28 consecutive days since 21 d after STZ injection.Morris water maze test was carried out to assess the spatial learning and memory abilities.Nissl staining and immunofluorescence assay were applied to observe neuronal morphology and number in the hippocampus and cortex.The iron content in the hippocampus was measured with inductively coupled plasma mass spectrometry(ICP-MS).The expression levels of iron metabolism related proteins were detected with Western blotting.Results In the T1DM group,significant declines in learning and memory abilities(P<0.01)and impaired neuronal morphology and reduced neuronal counts in the hippocampal CA1 region(P<0.01),CA3 region(P<0.01),and cortex(P<0.05)were observed when compared with those in the Ctrl group.ICP-MS analysis showed a marked increase in the hippocampal iron content in the T1DM group(P<0.01).Western blot results demonstrated that T1DM rats exhibited obviously up-regulated expression of iron storage proteins FTH and FTL in both the hippocampus(P<0.01,P<0.05)and the cortex(P<0.05,P<0.01),enhanced expression of iron import protein DMT1 in both the hippocampus and the cortex(P<0.05),while decreased expression of iron export protein FPN1 in the hippocampus(P<0.01)and the cortex(P<0.05).DFO treatment significantly ameliorated all above abnormalities.Conclusion The declines in learning and memory in T1DM rats are closely associated with neuronal damage induced by cerebral iron overload.Iron import protein DMT1 and export protein FPN1 jointly regulate cerebral iron content in T1DM rats.DFO reduces brain iron levels and mitigates iron overload-mediated neuronal injury by modulating the expression of DMT1 and FPN1.

Objective To investigate the independent risk factors affecting the prognosis of chronic active antibody-mediated rejection (caAMR) after kidney transplantation. Methods A retrospective analysis was conducted on 61 patients who underwent renal biopsy and were diagnosed with caAMR. The patients were divided into caAMR group (n=41) and caAMR+TCMR group (n=20) based on the presence or absence of concurrent acute T cell-mediated rejection (TCMR). The patients were followed up for 3 years. The value of 24-hour urinary protein and estimated glomerular filtration rate (eGFR) at the time of biopsy in predicting graft loss was assessed using receiver operating characteristic (ROC) curves. The independent risk factors affecting caAMR prognosis were analyzed using the LASSO-Cox regression model. The correlation between grouping, outcomes, and Banff scores was compared using Spearman rank correlation matrix analysis. Kaplan-Meier analysis was used to evaluate the renal allograft survival rates of each subgroup. Results The 3-year renal allograft survival rates for the caAMR group and the caAMR+TCMR group were 83% and 79%, respectively. The area under the ROC curve (AUC) for predicting 3-year renal allograft loss was 0.83 ［95% confidence interval (CI) 0.70-0.97］ for eGFR and 0.78 (95% CI 0.61-0.96) for 24-hour urinary protein at the time of biopsy. LASSO-Cox regression analysis and Kaplan-Meier analysis showed that eGFR≤25.23 mL/(min·1.73 m²) and the presence of donor-specific antibody (DSA) against human leukocyte antigen (HLA) class I might be independent risk factors affecting renal allograft prognosis, with hazard ratios of 7.67 (95% CI 2.18-27.02) and 5.13 (95% CI 1.33-19.80), respectively. A strong correlation was found between the Banff chronic lesion indicators of renal interstitial fibrosis and tubular atrophy (P<0.05). Conclusions The presence of HLA class I DSA and eGFR≤25.23 mL/(min·1.73 m²) at the time of biopsy may be independent risk factors affecting the prognosis of caAMR.

Objective: To analyze the status and trends of physical fitness test data among college freshmen with different body mass index (BMI) groups from 2014 to 2024, providing the scientific evidence for monitoring and intervening in college students physical health. Methods: A census was conducted on all 67 949 freshmen at Civil Aviation University of China from 2014 to 2024. Physical tests included vital capacity, sit and reach, sit ups, 50 m sprint, standing long jump, pull ups, and 800 m/1 000 m run. Freshmen were divided into underweight, normal weight, overweight and obese groups according to WHO BMI standards. The Kruskal-Wallis H test was used to compare differences in physical fitness indicators across gender and BMI groups, while the Mann-Kendall trend test was employed to detect upward or downward trends in physical indicators over time. Results: From 2014 to 2024, statistically significant differences were observed in vital capacity, 50 m sprint, standing long jump, and sit and reach among different BMI groups for both genders (boy: Z =2 396.40, 4 160.33, 4 662.23, 531.85; girl: Z =593.37, 308.86, 499.37, 128.70). Significant differences were also found in 1 000 m run and pull ups for boys, and 800 m run and sit ups for girls across BMI groups (boy: Z =6 574.80, 6 880.48; girl: Z =528.56, 146.18) ( P <0.01). Overall physical test scores showed a declining trend during 2014-2024, particularly pronounced in overweight and obese groups. Male vital capacity in 2014 exceeded national survey data( d =320 mL), with the gap widening to 734 mL by 2019, while the female vital capacity difference increased from 271 mL in 2014 to 576 mL in 2019. Male 1 000 m run times were 23.0 s and 17.5 s faster than national data in 2014 and 2019 respectively, while female 800 m run times were 22.3 s and 21.5 s faster than corresponding national data. Conclusions Physical health status among freshmen at this university varies across BMI groups and changes over time. Although overall test scores remain higher than national levels, the declining trend in physical fitness performance requires attention.

The Screening Tool of Older Persons' Prescriptions(STOPP)and the Screening Tool to Alert to Right Treatment(START)play a crucial role in identifying potentially inappropriate prescriptions among the elderly.As the aging population continues to grow, there is an urgent need for effective tools to address the challenges of multimorbidity and polypharmacy in elderly patients in China.However, the development of rational medication screening tools has significantly lagged, and there is currently a lack of sensitive and effective instruments in China.This article analyzes the newly added entries in the third edition of STOPP/START, aiming to provide a reference for managing multiple medication regimens and for the development of relevant tools for elderly patients in China.