How to process synovial fluid samples of gouty arthritis and extract its exosomes for subsequent cytokine analysis.

BACKGROUND: The comparative analysis of ultracentrifugation (UC) and polyethylene glycol (PEG)-based precipitation for the isolation of exosomes in gouty arthritis synovial fluid (GASF) is rarely reported, and it is not known whether different isolation methods can influence subsequent cytokine analysis. METHODS: GA patients were enrolled during a 1-year period from May 2021 to May 2022. Morphology, particle number, size, purity, protein concentration, and biomarker proteins of GASF-derived exosomes in both extraction methods were observed using transmission electron microscopy, nanoparticle tracer analysis, bicinchoninic acid assay, and Western blotting. An ELISA-based assay platform was used to detect the cytokines in exosomes using Meso Scale Discovery. RESULTS: Thirty-two cases of fresh GASF were taken and randomly divided between the UC group (n = 16) and the PEG group (n = 16). Transmission electron microscopy images and nanoparticle tracer analysis results showed round vesicles measuring 100 nm on average. The protein expressions of TSG101, CD63, and CD81 in exosomes of the 2 groups were measured via Western blotting. The number and protein concentration of GASF-derived exosome particles from the PEG group were significantly higher than that of the UC group (P < .001). However, in the purity estimation, the UC group reflected significantly higher exosomes extractability (P < .01). Expression of IL-6 and IL-8 in the GASF-derived exosomes were higher in the UC group (P < .05), showing a median of 3.31 (interquartile range, IQR: 0.84-13.16) pg/mL, and a median of 2.87 (IQR: 0.56-13.17) pg/mL, respectively; moreover, IL-1ß was mostly undetectable in the PEG group. CONCLUSION: The UC method was found to yield exosomes of a higher purity, albeit at a lower quantity but with more abundant inflammatory cytokines; whereas the opposite was the case for the PEG group. The chemical precipitation method might not be suitable in terms of extracting GASF-derived exosomes for inflammation and immunity studies.

Biomechanical Effect of Osteoporosis on Adjacent Segments After Anterior Cervical Corpectomy and Fusion.

BACKGROUND: Adjacent segmental degeneration (ASD) is one common long-term complication of anterior cervical corpectomy and fusion (ACCF), and osteoporosis is one basic disease in the elderly. After ACCF, patients may experience osteoporosis with age. However, the influence of osteoporosis on ASD remains unclear. The purpose of this study was to determine whether osteoporosis could affect the development of ASD following ACCF. METHODS: Three finite element models of the cervical spine, including 1 normal model, 1 ACCF model, and 1 ACCF with osteoporosis model, were constructed. ACCF was simulated at the C4-C6 level. A 73.6 N follower load and a 1 Nm moment were imposed on the normal model, and the same follower load together with an adjusted moment was applied to the ACCF model and the ACCF with osteoporosis model, to simulate movement in each direction. The range of motion, intradiscal pressure, shear stress on anulus fibrosus, and facet joint stress at C3-C4 and C6-C7 levels of the models were calculated. RESULTS: In this study, the normal model was well validated. In flexion, extension, right lateral bending, and right axial rotation, the overall range of motion was 8.92°, 19.7°, 15.37°, and 45.27° in the normal model, and the adjusted moment was 1.4 Nm, 2.7 Nm, 1.1 Nm, and 2.6 Nm in the ACCF model, and 1.3 Nm, 2.5 Nm, 1.1 Nm, and 2.4 Nm in the ACCF with osteoporosis model. Despite of a few exceptions, the maximum values of the outcome measurements were mostly found in the ACCF model, and the minimum values in the normal model. Compared with the ACCF model, most of the outcome measurements were decreased in the ACCF with osteoporosis model. CONCLUSIONS: Osteoporosis can retard the adverse influence of ACCF on adjacent segments.

Effect of Osteoporosis on Adjacent Segmental Degeneration After Posterior Lumbar Interbody Fusion Under Whole Body Vibration.

BACKGROUND: Adjacent segmental degeneration (ASD) is one of the common complications after posterior lumbar interbody fusion (PLIF). Both whole body vibration (WBV) and osteoporosis are important factors associated with the biomechanics of the lumbar spine. However, to the best of our knowledge, no studies have investigated the effects of osteoporosis on ASD after PLIF under WBV. METHODS: In the present study, using one normal model, one PLIF model and one PLIF with osteoporosis model of the L1-S1 segment were developed. A 5-Hz, 40-N sinusoidal vertical load was imposed on the superior surface of L1 of each model to simulate WBV, and the dynamic responses and maximal values of intradiscal pressure, shear stress on annulus fibrosus, total deformation, and disc bulge were evaluated in the L1-L2, L2-L3, L3-L4, and L5-S1 segments. RESULTS: At the L1-L2, L2-L3, and L3-L4 levels, the differences in the dynamic responses and maximal values in intradiscal pressure, shear stress, total deformation, and disc bulge between the PLIF and PLIF with osteoporosis models were slight. However, at the L5-S1 level, the dynamic response curves and maximal intradiscal pressure, shear stress, and disc bulge values in the PLIF with osteoporosis model were significantly lower than those in the PLIF model. CONCLUSIONS: Osteoporosis can mitigate the development of ASD in the lower adjacent segment but has no obvious influence on the upper adjacent segments during WBV.

Comparison Between Oblique Pulling Spinal Manipulation and Other Treatments for Lumbar Disc Herniation: A Systematic Review and Meta-Analysis.

OBJECTIVE: The purpose of this review was to compare oblique pulling spinal manipulation with other treatments for lumbar disc herniation. METHODS: Randomized controlled trials of oblique pulling manipulation versus other treatment for lumbar disc herniation were identified using the following databases: China National Knowledge Infrastructure, Wanfang Data, Chinese Science and Technology Periodical Database, PubMed, the Cochrane Library, Embase, Chinese Biological Medicine, and Web of Science. Data extraction was carried out based on inclusion and exclusion criteria, and meta-analysis were performed using RevMan 5.3 software. RESULTS: Nine relevant randomized controlled trials with a total of 887 patients were included. Meta-analysis revealed that oblique pulling manipulation was superior in effective rate to lumbar traction (risk ratio = 1.12; 95% confidence interval [CI]: 1.06-1.19; P < .01) and acupuncture (risk ratio = 1.22; 95% CI: 1.06-1.39; P < .01) and more effective in Visual Analog Scale score (mean difference = - 1.03, 95% CI: -1.32 to -0.74; P < .01) when compared to lumbar traction. It also demonstrated a favorable effect of modified oblique pulling manipulation in Japanese Orthopedic Association scores when compared with lumbar traction (mean difference = 1.66, 95% CI: 0.89 to 2.43; P < .01). CONCLUSION: In the treatment of lumbar disc herniation, oblique pulling spinal manipulation presented with a higher effective rate than acupuncture and lumbar traction. Manipulation had a favorable effect in alleviating pain, and modified oblique pulling manipulation had significant superiority in improving lumbar function when compared with lumbar traction. However, considering the low methodological quality of included studies, more rigorously designed trials should be performed in the future.