Objective:To analyze the safety and efficacy of single percutaneous vertebroplasty (PVP) in the treatment of multi-segment osteolytic spinal metastases.Methods:A retrospective analysis was conducted on 113 patients with multi-segment osteolytic spinal metastases treated with PVP at Beijing Friendship Hospital, Capital Medical University from January 2013 to December 2019, including 50 males and 63 females. The age ranged from 47 to 85 years, with a mean of (66.9±1.52) years. Patients were divided into two groups based on the number of affected vertebrae undergoing surgery: the conventional surgery group ( n=72), with a maximum of three vertebral bodies undergoing PVP during each surgery; the multivertebral surgery group ( n=41), received PVP on more than three vertebral bodies in one surgery. Visual analogue scale(VAS) of pain, Oswestry disability index (ODI), general health status (GH), and mental health status (MH) were assessed before and after PVP to evaluate the efficacy of the procedure. Complications of the patients were systematically assessed to evaluate safety. Measurement data was expressed as mean±standard deviation( ± s), independent sample t-test was used for inter-group comparison, and paired sample t-test was used for intra-group comparison; the comparison of count data was conducted using Chi-square test. Results:After 6 months of surgery, the ODI score, GH score and MH score of the conventional surgery group was (35.28±1.74)%, 57.85±2.11 and 61.20±3.67, all of which improved significantly compared to before surgery, and the difference was statistically significant ( P<0.05). After 6 months of surgery, the ODI score, GH score and MH score of the multivertebral surgery group was (35.67±1.92)%, 64.12±1.35 and 59.80±3.81, all of which improved significantly compared to before surgery, and the difference was statistically significant ( P<0.05). There was no significant difference in ODI score and MH score between the two groups after 6 months of surgery ( P>0.05). At one week after surgery, the pain VAS score in the conventional surgery group (3.51±0.21) was lower than that in the multivertebral surgery group (3.98±0.32), and the difference was statistically significant ( P<0.05). GH score in the conventional surgery group showed significantly greater improvement than that in the multivertebral surgery group after 6 months of surgery, and the difference was statistically significant ( P<0.05). Bone cement leakage occurred in 21 vertebra of the conventional surgery group, and 24 vertebra of the multivertebral surgery group, with leakage rates of 14.8% and 13.0%, respectively, with no statistical significance between the two groups ( P>0.05). Conclusions:Single PVP surgery can safely and effectively alleviate the pain of multi-segment osteolytic spinal metastases and improve spinal mobility. Meanwhile, improving mental health and reducing functional impairments. But the short-term pain relief and long-term general health of the multivertebral surgery group were lower than those of the conventional surgery group.

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.

Peroxisome proliferator-activated receptor gamma(PPAR-γ)is a member of the ligand-activated nuclear tran-scription factor superfamily.Activated PPAR-γ is involved in the regulation of many central nervous system(CNS)events,and is involved in cholesterol metabolism by inducing or inhibi-ting a series of gene pathways,thereby inhibiting the deposition of β-amyloid protein(Aβ).It plays an important neuroprotec-tive role in Alzheimer's disease(AD),improves memory and cognition in AD,and is a potential target for AD.Drug develop-ment aimed at restoring cholesterol homeostasis may be a poten-tial strategy to counteract AD.By analyzing the distribution and structure of PPAR-γ,focusing on the biological correlation be-tween PPAR-γ-mediated cholesterol metabolism and AD,this paper describes the mechanism regulation of PPAR-γ on key proteins,genes and their corresponding molecules,providing a new reference for the treatment of AD.

Objective To establish a new animal model of filum terminale traction tethered cord syndrome to explore its pathogenesis.Methods Sixteen New Zealand white rabbits were randomly divided into the traction group and the sham group,with 8 rabbits in each group.The traction group used silk thread to establish a model of filum terminale traction tethered cord syndrome,while the sham group only cut the filum terminale without traction.After 8 weeks,the behavioral Talov score,lumbosacral MRI examination,somatosensory evoked potential detection,urodynamic index test and pathological analysis were completed.Results At the 8th week after surgery,the hindlimb injury was obvious in the traction group,and the Talov scores at the 4th and 8th weeks after operation were lower than those in the sham group(P<0.001).The lumbosacral MRI results at 8 weeks after surgery showed that the distal filum terminale was pulled by silk thread,with bladder abnormal enlargement in sagital MRI in the traction group,while axial MRI showed the spinal cord within the spinal canal was subjected to mechanical forces in the downward and dorsal directions;the sagittal and axial MRI of the sham group showed that the spinal cord was located in the middle of the spinal canal and the bladder size was normal.At the 8th week after surgery,the amplitude in the traction group was significantly lower than that in the sham group(P<0.001),and the amplitude decreased by more than 50% .The overall latency period in the traction group was slightly longer than that in the sham group(P<0.05).The results of urodynamic examination showed that the maximum bladder capacity in the traction group was significantly higher than that in the sham group(Z=-3.361,P<0.001),the bladder pressure was significantly lower than that in the sham group(Z=-3.361,P<0.001),and the bladder compliance was significantly higher than that in the sham group(P<0.001).Pathological staining showed that the traction of the filum terminale on the spinal cord led to nerve tissue damage and degeneration of bladder epithelial cells.Conclusion This study successfully established a model of filum terminale traction tethered cord syndrome of New Zealand white rabbits,which can provide reference for exploring the pathogenesis of tethered cord and understanding the pathological process of spinal cord injury.

Ferroptosis is a recently discovered form of cell death,which is characterized by abnormal intracellular i-ron ion accumulation and lethal lipid peroxidation.The regulatory cell death is closely related to iron metabolism,a-mino acid metabolism,lipid metabolism and other metabolic pathways.Atherosclerosis underlies the pathogenesis of a variety of cardiovascular diseases.Recent studies have shown that in addition to classical death pathways such as apoptosis,necrosis and autophagy,ferroptosis is also involved in the occurrence and development of atherosclerosis.This article elaborates the mechanism of ferroptosis and its effect on atherosclerotic lesion-related cells and factors.

The current situation of deep learning applied to single-and multi-lead ECG detection of arrhythmia was reviewed.The problems of deep learning during the application in generalization,interpretability and time complexity were analyzed,and the countermeasures were put forward accordingly.It's pointed out deep learning would be applied widely in arrhythmia ECG detection with the development of the algorithm,dataset and hardware.[Chinese Medical Equipment Journal,2024,45(2):105-112]

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]

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: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.

Objective To evaluate the effects of high-fat diet on the pharmacokinetics of metronidazole in Chinese healthy adult subjects.Methods This program is designed according to a single-center,randomized,open,single-dose trial.Forty-seven healthy subjects were assigned to receive single dose of metronidazole tablets 200 mg in either fasting and high-fat diet state,and blood samples were taken at different time points,respectively.The concentrations of metronidazole in plasma were determined by high performance liquid chromatography-mass spectromentry.Results The main pharmacokinetic parameters of metronidazole in fasting state and high-fat diet state were as follows:Cmax were(4 799.13±1 195.32)and(4 044.17±773.98)ng·mL-1;tmax were 1.00 and 2.25 h;t1/2 were(9.11±1.73)and(9.37±1.79)h;AUC0_t were(5.59±1.19)x 104 and(5.51±1.18)x 104 ng·mL-1·h;AUC0_∞ were(5.79±1.33)x 104 and(5.74±1.32)× 104 ng·mL-1·h.Compared to the fasting state,the tmaxof the drug taken after a high fat diet was delayed by 1.25 h(P＜0.01),Cmax,AUC0_t,AUC0-∞ were less or decreased in different degrees,but the effects were small(all P＞0.05).Conclusion High-fat diet has little effects on the pharmacokinetic parameters of metronidazole,which does not significantly change the degree of drug absorption,but can significantly delay the time to peak.