Objective:To explore interspinous fusion capacity after interspinous distraction fusion (ISDF) device implantation, a preliminary biomechanical analysis and histological evaluation were performed.Methods:The experimental animals were procured from the Science and Research Laboratory Animal Center of Beijing Friendship Hospital, Capital Medical University. The animals were 8-9 weeks old and with an average weight of 25 kg. 15 mini-pigs were randomly divided into three groups, the sham operation group, the decompression group and the ISDF fixed decompression group, 5 animals per group. The sham operation group was treated with simple incision and exposed lamina suture. The decompression group received unilateral decompression and the ISDF fixed decompression group experienced unilateral hemilaminectomy decompression and ISDF fixation. The graft-bed site was filled with purified bone graft material without any autograft bone. After 6 months feeding, all experimental animals were sacrificed and the corresponding lumbar vertebrae was obtained. The samples were fixed on the spinal test system and the range of motion of flexion-extension, lateral bending and rotation were tested through a multiaxial robotic system. The ISDF device samples were embedded for hard tissue sections and stained with hematoxylin-eosin and toluidine blue to assess new bone formation. Normally distributed measurement data were expressed as mean±standard deviation( ± s), and independent samples t-test were used for comparisons between groups. Results:In comparison to the sham operation group, the decompression group exhibited a statistically significant increase in intervertebral mobility, with an average of 61.6% in anterior flexion, 44.7% in posterior extension, 65.0% in left lateral flexion, 49.6% in right lateral flexion, 83.8% in left rotation, and 64.2% in right rotation ( P<0.05). In comparison to the decompression group, the ISDF fixed decompression group exhibited a statistically significant decrease in intervertebral mobility, with an average of 40.0% in anterior flexion, 21.3% in posterior extension, 31.7% in left lateral flexion, 22.3% in right lateral flexion, 28.7% in left rotation, and 35.3% in right rotation ( P<0.05). Well-defined bone tissue can be observed in the histological images of ISDF fixed decompression group samples after 6 months. In the histological part, toluidine blue staining showed extensive new bone formation. The hyperchromatic osteoblasts cells and density bone tissue can be observed in hematoxylin-eosin staining slides. Conclusions:The implantation of ISDF provide the necessary stabilization for promoting fusion. The osteogenesis that occurs within graft-bed site of the ISDF device offers the possibility of interspinous fusion.

Objective To evaluate iron deposition in gray matter nuclei in patients with cerebral small vessel disease(CSVD)based on quantitative susceptibility mapping(QSM)and to analyze its correlation with cognitive function.Methods Patients with CSVD attending the outpatient clinic in the Department of Neurology at Xuanwu Hospital of Capital Medical University from December 2016 to November 2022,and healthy controls recruited from previous studies in the Department of Radiology and Nuclear Medicine at Xuanwu Hospital of Capital Medical University from September 2022 to November 2022 were retrospectively consecutively collected.Baseline data of CSVD patients and healthy controls was collected and compared,including age,sex,past history(hypertension,diabetes,hyperlipidemia),smoking history,alcohol consumption history and Montreal cognitive assessment(MoCA)scale score.MRI of all CSVD patients and healthy controls were collected,including three-dimensional T1 weighted imaging,QSM,T2 weighted imaging,and fluid attenuated inversion recovery(FLAIR)sequence imaging.According to the MRI-related imaging features and CSVD total burden score,the patients were divided into mild CSVD(CSVD-m)group and severe CSVD(CSVD-s)group,and healthy controls were the control group.QSM was used to obtain the susceptibility values of gray matter nuclei for all CSVD patients and controls.One-way covariance analysis and Bonferroni correction were used to compare the gray matter nuclei susceptibility values among the three groups.Spearman correlation analysis was performed between susceptibility values of gray matter nuclei with statistically significant differences in susceptibility values and cognitive function.Results A total of 61 cases of CSVD patients were included,including 29 cases in the CSVD-s group and 32 cases in the CSVD-m group;32 healthy controls were included in the control group.(1)There was no statistically significant difference in age,sex,hypertension,diabetes,hyperlipidemia,smoking,and alcohol consumption between the CSVD-s group,CSVD-m group and control group(all P＞0.05).The MoCA scale scores of the CSVD-s group and CSVD-m group were lower than those of the control group(25.0[22.5,27.5]points,27.0[25.0,29.0]points than 28.0[27.0,29.0]points,H=15.006,P＜0.01).The difference in the imaging features distribution of cerebral microbleeds,white matter hyperintensity,and perivascular space among the CSVD-s group and the CSVD-m group was statistically significant(all P＜0.05).(2)The differences in susceptibility values of the left putamen(F=4.790),pallidus(F=12.896),hippocampus(F=3.904)and the right putamen(F=36.278),pallidus(F=39.449),caudate nucleus(F=6.797),and thalamus(F=6.525)were statistically significant among the three groups(all P＜0.05).After Bonferroni correction,the susceptibility values of the left putamen and pallidus and the right putamen,pallidus,caudate nucleus,and thalamus in the CSVD-s group were higher than those of the control group(all P＜0.05);the susceptibility values of the left pallidus and the right pallidus,putamen,and thalamus in the CSVD-m group were higher than those of the control group(all P＜0.01),and the left hippocampus was lower than that of the control group(P=0.045).(3)The susceptibility values of the bilateral putamen were significantly negatively correlated with MoCA scale score(left putamen:rs=-0.316,P=0.015;right putamen:rs=-0.316,P=0.014).Conclusion Abnormal iron metabolism occurs in gray matter nuclei of CSVD patients,and iron deposition in the putamen correlate with cognitive dysfunction.

Objective:To compare the safety and efficacy of two different minimally invasive approaches to implant pedicle screw for the treatment of single-segment thoracolumbar spine fractures without nerve injury.Methods:This was a retrospective study. Eighty patients with mono-segmental thoracolumbar fractures treated with minimally invasive pedicle screw fixation at Beijing Friendship Hospital, Capital Medical University from January 2020 to June 2022 were included. There were 46 males and 36 females, the age was (45.93±7.91) years old, and ranged from 27 to 60 years old. They were divided into two groups according to different surgical techniques: percutaneous pedicle screw fixation group ( n=44) and Wiltse approach group ( n=36). The operative time, operative visible blood loss, hidden blood loss, total blood loss, fluoroscopy times, incision length, hospital time after surgery and ambulation time were compared. Visual analogue scale (VAS), Oswestry disability index (ODI), ratio of the vertebral anterior height, angle of injured vertebral endplate were recorded and compared between two groups before surgery and at 3 days, 6 months and 1 year after surgery. The accuracy of pedicle screw position and the facet joint violation rate were evaluated by using the postoperative CT scan. Perioperative related complications were investigated. Normally distributed numerical data were presented as mean ± standard deviation, and differences between the groups were compared using t-test. The counting data were expressed as percentages or rates and compared using χ2 test. Results:All patients were followed for a minimum of 12 months. There is no significant difference between the two groups in intraoperative visible blood loss, hospital time after surgery, ambulation time, postoperative VAS and ODI, ratio of vertebral anterior height and angle of injured vertebral endplate at 3 days after surgery, pedicle screw position accuracy and perioperative complications ( P>0.05). The operative time, hidden blood loss, total blood loss, intraoperative fluoroscopy times, facet joint violation rate in the percutaneous pedicle screw fixation group were remarkably higher than in the Wiltse approach group ( P<0.05). The ratio of vertebral anterior height in the percutaneous pedicle screw fixation group was dramatically lower than in the Wiltse approach group at 6 months and 1 year after surgery ( P<0.05). The postoperative injured vertebral endplate angle was higher in the percutaneous pedicle screw fixation group than that in the Wiltse approach group at 6 months and 1 year ( P<0.05). Conclusions:Both percutaneous pedicle screw fixation and Wiltse approach were safe and effective minimally invasive surgical procedures for the treatment of thoracolumbar fractures without neurological injury. The Wiltse approach can reduce fluoroscopy times and perioperative hidden blood loss, reduce the risk of facet joint violation, and maintain a better reduction than percutaneous pedicle screw fixation.

BACKGROUND:Ankylosing spondylitis is a chronic inflammatory disease with chronic rheumatic immunity.Soft tissue ossification and fusion and spinal stiffness can cause biomechanical changes. OBJECTIVE:To reconstruct the lumbar-sacral intervertebral disc in ankylosing spondylitis patients with lumbar kyphosis by finite element analysis,and to study the range of motion of each segment of T11-S1 and the biomechanical characteristics of annulus fibrosus and nucleus pulposus. METHODS:The imaging data were obtained from an ankylosing spondylitis patient with lumbar kyphosis.The original CT image data of continuously scanned spine were imported into Mimics 21.0 in DICOM format,and T11-S1 was reconstructed respectively.The established model was imported into 3-Matic software in the format of"Stl"to reconstruct the intervertebral disc,and the fibrous intervertebral disc model was obtained.The improved model was further imported into Hypermesh software,and the vertebra,nucleus pulposus,annulus fibrosus and ligament were mesh-divided.After the material properties were given,the model was imported into ABAQUS software to observe the range of motion of each vertebral body in seven different working conditions of T11-S1,and analyze the biomechanical characteristics of each segment of annulus fibrosus and nucleus pulposus. RESULTS AND CONCLUSION:(1)The range of motion of L1 vertebrae was higher than that of other vertebrae under six different working conditions:extension,forward flexion,rotation(left and right),and lateral flexion(left and right).The maximum range of motion was 2.18° during L1 vertebral flexion,and the minimum range of motion was 0.12° during L5 vertebral extension.(2)The annular fiber flexion at L2-L3 segments was greater than the extension(P<0.05),and the annular fiber flexion at L3-L4 and L4-L5 segments was less than the extension(P<0.05).The left rotation of L1-L2 annular fibers was greater than the right rotation(P<0.05).The left flexion of the annulus was greater than the right flexion in L1-L2,L2-L3,L3-L4,L4-L5 and L5-S1 segments(P<0.05).(3)The nucleus pulposus stresses of T11-L12,L1-L2,L2-L3,L3-L4 and L4-L5 segments in forward flexion were greater than in extension(P<0.05).The left rotation of T12-L1 and L3-L4 segments was smaller than the right rotation(P<0.05),and that of T11-T12,L1-L2,and L2-L3 segments was larger than the right rotation(P<0.05).The left flexion was larger than the right flexion in the T11-S1 segment.(4)It is concluded that in ankylosing spondylitis patients with lumbar kyphosis,the minimum range of motion of the vertebral body is located at the L5 vertebral body in extension.To prevent fractures,it is recommended to avoid exercise in the extension position.During the onset of lumbar kyphosis in patients with ankylosing spondylitis,the maximum stress of the annulus fibrosus and nucleus pulposus is located in the L1-L2 segment,which is fixed and will not alter with the change of body position.The late surgical treatment and correction of deformity should focus on releasing the pressure of the annulus fibrosus and nucleus pulposus in this segment to avoid the rupture of the annulus fibrosus and the injury of the nucleus pulposus.

BACKGROUND:Interspinous distraction fusion device BacFuse was used for the management of lumbar degenerative disease and obtained good clinical efficacy in recent years.However,the related biomechanical study was lacking. OBJECTIVE:To explore the related biomechanical characteristics of BacFuse,a novel interspinous distraction fusion device,which was used in lumbar degenerative disease. METHODS:After constructing the goat spinal models(L1-L6),they were grouped into four groups based on different simulated surgeries:the control group,the BacFuse group(L3/4),the screw-rod fixation group(L3/4)and the Topping-off group(L3/4 screw-rod fixation + L2/3 BacFuse fixation).The goat lumbar spine surgical model was assembled into a biomechanical testing system.A biomechanical machine was used for mechanical loading,simulating lumbar spine movement of flexion,extension,lateral flexion and rotation with a 4 Nm moment.A visual tracking system was used for positioning and capturing.Finally,mechanical and optical calibration was completed to calculate the range of motion of the L2/3,L3/4 and L4/5 segments. RESULTS AND CONCLUSION:(1)Compared with the control group,the range of motion of the L3/4 segment in the BacFuse group decreased 27.27%,70%,38.1%and 23.08%in the flexion,extension,lateral bending and rotation directions,respectively(P<0.05).The range of motion of L3/4 segment in the screw-rod fixation group decreased 72.73%,80%,71.43%and 73.08%in the flexion,extension,lateral bending and rotation directions,respectively(P<0.05).(2)Compared with the control group,the range of motion of the adjacent segment L2/3 increased by 33.33%,25%and 23.81%in the extension,lateral bending and rotation directions,respectively in the BacFuse group(P<0.05),with no significant change in flexion.In the screw-rod fixation group,there was a 50%,44.44%,50%and 58.96%increase in the adjacent segment L2/3 in the flexion,extension,lateral calibration and rotation directions,respectively(P<0.05).(3)Compared with the control group,the BacFuse group showed an increase in range of motion in proximal segment L4/5 in the extension and rotation directions by 27.3%and 17.39%(P<0.05)respectively,with no significant change in flexion or lateral bending.In the screw-rob fixation group,the proximal segment L4/5 demonstrated 38.89%,22.73%and 26.09%(P<0.05)increases in range of motion in the flexion,extension and rotation directions,respectively,with no significant change in lateral bending.(4)In the Topping-off group,the range of motion of L2/3 was reduced by 37.04%,73.08%,56.67%and 38.46%in flexion,extension,lateral flexion and rotation,respectively,compared to the screw-rob fixation group(P<0.05).Compared with the screw-rob fixation group,the Topping-off group showed a 20%reduction in the range of motion of the L4/5 in the flexion direction(P<0.05),with no significant differences seen in extension,lateral bending and rotation.(5)It is concluded that the interspinous distraction fusion device BacFuse significantly reduces the range of motion of the implanted segment and provides some stability.It still retains more mobility and reduces the impact on the adjacent segment compared to screw-rob fixation,while the Topping-off tip,which can be used for intervertebral fusion fixation,significantly reduces the range of motion of the adjacent segment and reduces the risk of adjacent segment degeneration.

The innovation of integrating medical treatment and prevention mechanisms is a key task deployed by the government, aiming to promote the construction of a Healthy China and address the prevalent "treatment over prevention" mindset in healthcare services and society. Vaccination is an effective strategy for preventing and controlling infectious diseases; however, adult vaccination rates in China remain low due to insufficient awareness and enthusiasm among the public and healthcare professionals. In recent years, various regions have begun to explore the model of physicians in medical institutions prescribing vaccines to improve vaccination rates. This article analyzes the positioning, current implementation status, and challenges of vaccine prescriptions, and proposes recommendations advocating policy formulation, improving service models and supporting measures, improving funding mechanisms, and strengthening publicity and education to promote the widespread implementation and effectiveness of vaccine prescriptions.

Vaccination is an effective public health measure to prevent and control vaccine-preventable diseases for individual and society. However, China currently confronts significant challenges, including a dearth of skilled professionals in the field of vaccination and disparities in the capacity for immunization services. This review introduced the experiences of four prime international vaccinology education models, including London School of Hygiene & Tropical Medicine, Johns Hopkins University, Leading International Vaccinology Education, and the Bill & Melinda Gates Foundation, in the aspect of personnel development, academic research and communication platforms establishment. It is supposed to give some insights and feasible suggestions on the establishment and advancement of vaccinology as a sub-discipline within high-level public health school in China, with the aim of development of a robust vaccinology education framework in China, which is essential for nurturing the next generation of public health leaders and practitioners for our country.

The innovation of integrating medical treatment and prevention mechanisms is a key task deployed by the government, aiming to promote the construction of a Healthy China and address the prevalent "treatment over prevention" mindset in healthcare services and society. Vaccination is an effective strategy for preventing and controlling infectious diseases; however, adult vaccination rates in China remain low due to insufficient awareness and enthusiasm among the public and healthcare professionals. In recent years, various regions have begun to explore the model of physicians in medical institutions prescribing vaccines to improve vaccination rates. This article analyzes the positioning, current implementation status, and challenges of vaccine prescriptions, and proposes recommendations advocating policy formulation, improving service models and supporting measures, improving funding mechanisms, and strengthening publicity and education to promote the widespread implementation and effectiveness of vaccine prescriptions.

Vaccination is an effective public health measure to prevent and control vaccine-preventable diseases for individual and society. However, China currently confronts significant challenges, including a dearth of skilled professionals in the field of vaccination and disparities in the capacity for immunization services. This review introduced the experiences of four prime international vaccinology education models, including London School of Hygiene & Tropical Medicine, Johns Hopkins University, Leading International Vaccinology Education, and the Bill & Melinda Gates Foundation, in the aspect of personnel development, academic research and communication platforms establishment. It is supposed to give some insights and feasible suggestions on the establishment and advancement of vaccinology as a sub-discipline within high-level public health school in China, with the aim of development of a robust vaccinology education framework in China, which is essential for nurturing the next generation of public health leaders and practitioners for our country.

Objective To explore the value of biparametric magnetic resonance imaging(bp-MRI)radiomics models in noninvasive prediction of high-risk prostate cancer.Methods A total of 320 patients with pathologically confirmed prostate cancer were retro-spectively selected,and all patients underwent bp-MRI before pathology,including T2WI and diffusion weighted imaging(DWI).Appar-ent diffusion coefficient(ADC)maps were extracted from DWI.All patients were divided into high-risk(Gleason score≥8)and medium-low risk(Gleason score ≤7)groups based on the Gleason score.Using 3D Slicer software,the entire prostate gland was outlined.Python software was used to calculate parameters,and the minimum redundancy maximum correlation and sequence back-ward elimination algorithms were used to extract and select radiomics features and to build a model.Three radiomics(T2 WI,DWI,ADC)models were constructed and verified by logistic regression(LR).The performance of the model was evaluated by area under the curve(AUC)of receiver operating characteristic(ROC)curve,specificity(SP),sensitivity(SE),and accuracy(ACC).An indi-vidual prediction model was established via the clinical data of 224 patients and bp-MRI features,and validated via the data of 96 patients.Results A total of 1 165 radiomics features were extracted.After feature screening,2,4 and 6 radiomics features were screened out to construct T2WI model,DWI model and ADC model for predicting high-risk prostate cancer.All radiomics models had significant predictive performance in identifying medium-low risk and high-risk groups(P＜0.05).The DWI model had the highest predictive value,and the AUC,ACC,SE,and SP in the training group were 0.814,0.756,0.838,and 0.744,respectively.The AUC,ACC,SE,and SP in the verification group were 0.840,0.756,0.848,and 0.784,respectively.Conclusion Radiomics based on bp-MRI can better identify medium-low risk and high-risk prostate cancer before surgery.