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.

Glycosylation is one of the most important reactions in living organisms as it results in the formation of glycoconjugates with diverse biological functions. Sugar nucleotides are structurally composed of sugar and nucleoside diphosphate or monophosphate, which are widespread within a variety of biological cells. As glycosyl donors for the transglycosyl reactions catalyzed by Leloir-type glycosyltransferases, sugar nucleotides are essential for the synthesis of glycans and glycoconjugates. However, high costs and limited availability of nucleotide sugars prevent applications of biocatalytic cascades on an industrial scale. Therefore, attentions on synthetic strategies of sugar nucleotides have been increasing to achieve their wide applications in various fields. The 9 common sugar nucleotides in mammals have been fully studied with large-scale synthesis through chemical, enzymatic (chemo-enzymatic) and cell factory strategies. In addition to common sugar nucleotides, many rare sugar nucleotides are present in plants and bacteria. Although unnatural sugar nucleotides cannot be synthesized in organisms, they have great potential in research as substrates for glycosyltransferases in carbohydrate synthesis, as enzyme inhibitors in biochemical studies, and as components of glycoconjugate biosynthesis. Therefore, increasing attention has been paid to explore the efficient synthesis of unnatural sugar nucleotides. Currently, strategies for chemical synthesis of sugar nucleotides have been greatly improved, such as the use of effective catalysts for forming pyrophosphate bonds and the development of entirely new synthesis protocols. Multiple sugar nucleotides, especially unnatural sugar nucleotides, are synthesized chemically. However, chemical synthesis requires tedious protection and deprotection steps, resulting in complex steps, high cost and low yield. In contrast, enzymatic (chemo-enzymatic) and cell factory methods have significant advantages such as high yield, easy operation and easy process scale-up in the preparation of sugar nucleotides. Hence, they are prominent strategies for sugar nucleotide preparation. Herein, the biosynthesis and application of sugar nucleotides are reviewed, mainly focusing on the 9 sugar nucleotides common in mammals. The early strategies for enzymatic synthesis of sugar nucleotides generally used de novo synthesis pathway. With the discoveries of enzymes involved in salvage pathway of sugar nucleotide synthesis and the development of one-pot multienzyme (OPME) method, the synthesis of sugar nucleotides was greatly simplified. Cell factory method employs the microbial living cells as a “processing plant” by engineering their metabolic pathways through genetic engineering technology. The cell factory method has high yield, and has been applied for efficient synthesis of several sugar nucleotides. Moreover, the strategy of gram-scale synthesis of multiple rare sugar nucleotides by cascade reactions from common sugar nucleotides using sugar nucleotides synthases cloned from different sources was illustrated. In recent years, the synthesis cost of sugar nucleotides has been further reduced through various ways, such as regeneration of nucleotides, regeneration of organic cofactors, and application of immobilized enzyme technology. Furthermore, through the continuous improvement of sugar nucleotide purification process, the use of high concentration of multi-enzyme cascade and rapid non-chromatographic purification process, the synthesis of multiple sugar nucleotides and their derivatives from monosaccharides was achieved, which gradually broke the limitations of the existing strategy. With the efficient synthesis of sugar nucleotides, their applications in various fields have been increasingly explored, including the synthesis of glycans and glycoconjugates, biochemical characterization of glycosyltransferases and bioorthogonal labeling strategies, which are of great significance to the research of biochemistry, glycobiology and the development of related pharmaceutical products.

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.

Objective:To investigate the changes of artemin protein expression in diabetic peripheral neuropathy (DPN) and to explore the regulatory effect of human adipose-derived stem cell (ADSC) exosomes on the change of artemin protein expression.Methods:This research was a prospective observational clinical research combined with experimental research. Thirteen DPN patients (9 males and 4 females, aged 32 to 68 years) who were admitted to the First Affiliated Hospital of Air Force Medical University (hereinafter referred to as our hospital) from May 2022 to October 2023 and met the inclusion criteria were selected as DPN group, and 5 non-diabetes patients (4 males and 1 female, aged 29 to 61 years) who were admitted to our hospital in the same period of time and met the inclusion criteria were selected as control group. The toe nerve or sural nerve tissue in the abandoned tissue after debridement or amputation of patients in the two groups was collected. The pathological changes of nerve tissue were observed after hematoxylin-eosin staining; the protein expressions of S100β and artemin in nerve tissue were observed after immunofluorescence staining, and the artemin protein expression was quantified; the protein and mRNA expressions of artemin were detected by Western blotting and real-time fluorescent quantitative reverse transcription polymerase chain reaction, respectively (the sample number in DPN group and control group was 13 and 5, respectively). Twelve male C57BL/6 mice aged 3 to 5 days were collected to isolate Schwann cells, and the cells were divided into conventional culture group cultured routinely, high glucose alone group (cultured with high concentration of glucose solution only), and high glucose+exosome group (cultured with high concentration of glucose solution and extracted human ADSC exosomes). After 24 hours of culture, the cell proliferation activity was detected by cell counting kit 8 ( n=6). After 48 hours of culture, the protein expression of artemin was detected by Western blotting ( n=3). Results:Compared with those in control group, the neural supporting cells decreased and the inflammatory cells increased in the nerve tissue of patients in DPN group, showing typical manifestations of nerve injury. Immunofluorescence staining showed that compared with those in control group, the nuclei was more, and the protein expression of S100β was lower in nerve tissue of patients in DPN group. The protein expression of artemin in nerve tissue of patients in DPN group was 71±31, which was significantly lower than 1 729±62 in control group ( t=76.92, P<0.05). Western blotting detection showed that the protein expression of artemin in nerve tissue of patients in DPN group was 0.74±0.08, which was significantly lower than 0.97±0.06 in control group ( t=5.49, P<0.05). The artemin mRNA expression in nerve tissue of patients in DPN group was significantly lower than that in control group ( t=7.65, P<0.05). After 24 hours of culture, compared with that in conventional culture group, the proliferation activities of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased ( P<0.05); compared with that in high glucose alone group, the proliferation activity of Schwann cells in high glucose+exosome group was significantly increased ( P<0.05). After 48 hours of culture, compared with those in conventional culture group, the protein expressions of artemin of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased ( P<0.05); compared with that in high glucose alone group, the protein expression of artemin of Schwann cells in high glucose+exosome group was significantly increased ( P<0.05). Conclusions:The protein expression of artemin in nerve tissue of DPN patients is lower than that in normal nerve tissue, which may be related to the reduction of proliferation activity of Schwann cells by high glucose. Human ADSC exosomes may improve the proliferation activity of Schwann cells by increasing artemin protein expression, thereby delaying the progression of DPN.

Objective To explore the postmortem diffusion rule of Aconitum alkaloids and their metabo-lites in poisoned rabbits,and to provide a reference for identifying the antemortem poisoning or post-mortem poisoning of Aconitum alkaloids.Methods Twenty-four rabbits were sacrificed by tracheal clamps.After 1 hour,the rabbits were administered with aconitine LD50 in decocting aconite root powder by intragastric administration.Then,they were placed supine and stored at 25℃.The biological samples from 3 randomly selected rabbits were collected including heart blood,peripheral blood,urine,heart,liver,spleen,lung and kidney tissues at 0 h,4 h,8 h,12 h,24 h,48 h,72 h and 96 h after intragastric administration,respectively.Aconitum alkaloids and their metabolites in the biological samples were ana-lyzed by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).Results At 4 h after intragastric administration,Aconitum alkaloids and their metabolites could be detected in heart blood,peripheral blood and major organs,and the contents of them changed dynamically with the preservation time.The contents of Aconitum alkaloids and their metabolites were higher in the spleen,liver and lung,especially in the spleen which was closer to the stomach.The average mass fraction of benzoylmesaconine metabolized in rabbit spleen was the highest at 48 h after intragastric administration.In contrast,the contents of Aconitum alkaloids and their metabolites in kidney were all lower.Aconi-tum alkaloids and their metabolites were not detected in urine.Conclusion Aconitum alkaloids and their metabolites have postmortem diffusion in poisoned rabbits,diffusing from high-content organs(stomach)to other major organs and tissues as well as the heart blood.The main mechanism is the dispersion along the concentration gradient,while urine is not affected by postmortem diffusion,which can be used as the basis for the identification of antemortem and postmortem Aconitum alkaloids poisoning.

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.

Uric acid (UA) is the final product of purine metabolism in human body,and its metabolic disorder will induce hyperuricemia (HUA).The occurrence and development of HUA are associated with a variety of pathological mechanisms such as oxidative stress injury,activation of inflammatory cytokines,and activation of renin-angiotensin-aldosterone system.These mechanisms directly or indirectly affect the bioavailability of endogenous nitric oxide (NO).The decrease in NO bioavailability is common in the diseases with high concentration of UA as an independent risk factor.In this review,we summarize the mechanisms by which high concentrations of UA affect the endogenous NO bioavailability,with a focus on the mechanisms of high-concentration UA in decreasing the synthesis and/or increasing the consumption of NO.This review aims to provide references for alleviating the multisystem symptoms and improving the prognosis of HUA,and lay a theoretical foundation for in-depth study of the correlations between HUA and other metabolic diseases.
Humans ; Nitric Oxide ; Uric Acid ; Hyperuricemia ; Biological Availability ; Cytokines

This study aimed to provide scientific evidence for predicting quality markers(Q-markers) of Elephantopus scaber by establishing UPLC fingerprint of E. scaber from different geographical origins and determining the content of 13 major components, as well as conducting in vitro anti-cancer activity investigation of the main components. The chromatographic column used was Waters CORTECS UPLC C_(18)(2.1 mm×150 mm, 1.6 μm), and the mobile phase consisted of acetonitrile and 0.1% formic acid solution(gradient elution). The column temperature was set at 30 ℃, and the flow rate was 0.2 mL·min~(-1). The injection volume was 1 μL, and the detection wavelength was 240 nm. The UPLC fingerprint of E. scaber was fitted using the Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine(2012 edition) to determine common peaks, evaluate similarity, identify and determine the content of major components. The CCK-8 assay was used to explore the inhibitory effect of the main components on the proliferation of lung cancer cells. The results showed that in the established UPLC fingerprint of E. scaber, 35 common peaks were identified. Thirteen major components, including neochlorogenic acid(peak 1), chlorogenic acid(peak 2), cryptochlorogenic acid(peak 3), caffeic acid(peak 4), schaftoside(peak 6), galuteolin(peak 9), isochlorogenic acid B(peak 10), isochlorogenic acid A(peak 12), isochlorogenic acid C(peak 18), deoxyelephantopin(peak 28), isodeoxyelephantopin(peak 29), isoscabertopin(peak 31), and scabertopin(peak 32) were identified and quantified, and a quantitative analysis method was established. The results of the in vitro anti-cancer activity study showed that deoxyelephantopin, isodeoxyelephantopin, isoscabertopin, and scabertopin in E. scaber exhibited inhibition rates of lung cancer cell proliferation exceeding 80% at a concentration of 10 μmol·L~(-1), higher than the positive drug paclitaxel. These results indicate that the fingerprint of E. scaber is highly characteristic, and the quantitative analysis method is accurate and stable, providing references for the research on quality standards of E. scaber. Four sesquiterpene lactones in E. scaber show significant anti-cancer activity and can serve as Q-markers for E. scaber.
Humans ; Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal/chemistry* ; Asteraceae/chemistry* ; Lung Neoplasms/drug therapy*

Objective:To identify the genetic variation in a mucopolysaccharidosis type Ⅱ(MPS Ⅱ)family, and conduct a functional study of iduronate-2-sulfatase(IDS): c.323A>C.Methods:A five-generation MPS Ⅱ family of 83 individuals including 4 patients from northern China was collected. Urine mucopolysaccharide and Alder-Reilly body were tested to assist the clinical diagnosis of MPS Ⅱ. IDS enzyme activity was detected on core family members. By the whole exome sequencing of a MPS Ⅱ patient in this family and bioinformatics analysis, the variant was screened and further identified by PCR-Sanger sequencing. Finally, to validate the function of the variant in vitro, the wild-type IDS overexpression plasmid(pCMV-hIDS-WT)and the IDS overexpression plasmid carrying the mutation site(pCMV-hIDS-c.323A>C)were transfected into COS-7 cells and the IDS activity was detected. Results:The proband(Ⅳ3)and Ⅳ4 were diagnosed as MPS Ⅱ by urine mucopolysaccharide, Alder-Reilly body, and IDS enzyme activity tests. Ⅳ3, Ⅳ4, Ⅲ19, and Ⅲ32 were determined to carry IDS: c.323A>C missense variant through the whole-exome sequencing, and diagnosed as MPS Ⅱ. Meanwhile, Ⅱ2, Ⅱ4, Ⅱ8, Ⅱ12, Ⅱ14, Ⅲ5, Ⅲ7, Ⅳ14 in the MPS Ⅱ family carried IDS: c.323A>C missense variant, and were excluded as MPS Ⅱ. The in vitro experiment in COS-7 cells showed that the missense mutation led to a significant decrease in IDS enzyme activity. Conclusion:The variant IDS: c.323A>C: p.Y108S significantly decreases the activity of IDS enzyme in vivo and in vitro, and it is identified as a pathogenic variant for MPS Ⅱ.