The influence of anterior cervical discectomy and fusion surgery on cervical muscles and the correlation between related muscle changes and surgical efficacy.

BACKGROUND: Anterior cervical discectomy and fusion surgery (ACDF) is a common technique in treating degenerative cervical spondylosis. This study is to evaluate the changes of cervical muscles after ACDF and analyze the correlation between related muscle changes and clinical efficacy. METHODS: Sixty-five postoperative patients (single-level ACDF) with cervical spondylotic myelopathy from January 2013 to December 2022 were analyzed. The measured parameters include: the axial section of longus colli cross-sectional area (AxCSA), the volume of cervical longus, the ratio of long and short diameter line (RLS), the cervical extensor cross-sectional area (CESA), the vertebral body area (VBA), and the CESA/VBA. The visual analog scale (VAS), modified Japanese Orthopedic Association score (mJOA), and neck disability index (NDI) were evaluated. The changes in muscle morphology were analyzed, and the correlation analysis was conducted between morphological changes and function scores. RESULTS: The postoperative AxCSA of surgical segment (3rd month, 12th month, and the last follow-up) was decreased compared to preoperative (141.62 ± 19.78), and the differences were significant (P < 0.05). The corresponding data reduced to (119.42 ± 20.08) mm2, (117.59 ± 19.69) mm2, and (117.41 ± 19.19) mm2, respectively (P < 0.05). The RLS increased, and the volume of cervical longus decreased significantly after surgery (P < 0.05). Negative correlation was found between postoperative volume of cervical longus and VAS at the 3rd month (r = - 0.412), 12th month (r = - 0.272), and last follow-up (r = - 0.391) (P < 0.05). Negative correlation existed between postoperative volume of cervical longus and NDI at the 3rd month (r = - 0.552), 12th month (r = - 0.293), and last follow-up (r = - 0.459) (P < 0.05). CONCLUSION: The volume of cervical longus decreased and its morphology changed after ACDF surgery. The mainly affected muscle was the cervical longus closing to the surgical segment. Negative correlation was found between the postoperative volume of cervical longus and function scores (VAS and NDI).

Unilateral biportal endoscopic lumbar interbody fusion (ULIF) versus endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) in the treatment of lumbar spinal stenosis along with intervertebral disc herniation: a retrospective analysis.

OBJECTIVE: This study aims to compare the clinical effects and imaging data of patients who underwent endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) with those who received unilateral biportal endoscopic lumbar interbody fusion (ULIF). METHODS: A retrospective analysis was conducted on the clinical data of 69 patients presenting with typical intermittent claudication and signs and symptoms indicative of unilateral lower extremity nerve root compression, meeting inclusion criteria between April 2022 and June 2022. Among the cohort, 35 patients underwent ULIF group, while 34 patients underwent Endo-TLIF group. We compared perioperative parameters, including intraoperative blood loss, duration of hospital stay, and operation time between the two groups. Pre-operative and post-operative changes in the height and cross-sectional area of the target intervertebral space were also compared between the groups. Finally, we evaluated bone graft size and interbody fusion rates at 6 and 12 months post-surgery using the Brantigan scoring system. RESULTS: The ULIF group had significantly shorter operative times compared to the Endo-TLIF group (P < 0.05). Conversely, the Endo-TLIF group exhibited significantly shorter hospital stays compared to the ULIF group (P < 0.05). However, there were no significant differences in intraoperative bleeding between the two groups (P > 0.05). Furthermore, both groups exhibited postoperative increases in vertebral canal volume compared to baseline (P < 0.05), with no significant difference in the change in the cross-sectional area of the target intervertebral space between the two surgical methods (P > 0.05). Interbody fusion rates were comparable between the two groups at both 6 and 12 months after surgery (P > 0.05). Lastly, the ULIF group had a significantly larger area of bone graft than the Endo-TLIF group (P < 0.05). CONCLUSION: In summary, the ULIF technique, as a novel spinal endoscopy approach, is a safer and more effective minimally invasive surgical method for addressing lumbar spinal stenosis and intervertebral disc herniation in patients. Both surgical methods have their own advantages and drawbacks. With the development of technology and related instruments, the limitations of both techniques can be mitigated for to a certain extent, and they can be applied by more doctors in diverse medical fields in the future.

Minimal Clinically Important Differences in Gait and Balance Ability in Patients Who Underwent Corrective Long Spinal Fusion for Adult Spinal Deformity.

STUDY DESIGN: Retrospective observational study. BACKGROUND: The risk of a femoral neck fracture due to a fall after adult spinal deformity surgery has been reported. One of the most significant factors among walking and balance tests in post-operative ASD patients was the timed up-and-go test (TUG). This study aims to calculate the minimal clinically important difference (MCID) in balance tests after ASD surgery. METHODS: Forty-eight patients, 4 males and 44 females, were included by exclusion criteria in 66 consecutive patients who underwent corrective surgery as a treatment for ASD at our institution from June 2017 to February 2022. The inclusion criteria for this study were age ≥50 years; and no history of high-energy trauma. The exclusion criteria were dementia, severe deformity of the lower extremities, severe knee or hip osteoarthritis, history of central nervous system disorders, cancer, and motor severe paralysis leading to gait disorders. The surgeries were performed in two stages, first, the oblique lumber interbody fusion (OLIF) L1 to L5 (or S1), and second, the posterior corrective fusion basically from T10 to pelvis. For outcome assessment, 10 m walk velocity, TUG, ODI, and spinopelvic parameters were used. RESULTS: Ten meter walk velocity of pre-operation and post-operation were 1.0 ± 0.3 m/s and 1.2 ± 0.2 m/s, respectively (p < 0.01). The TUG of pre-operation and post-operation were 12.1 ± 3.7 s and 9.7 ± 2.2 s, respectively (p < 0.01). The ODI improved from 38.6 ± 12.8% to 24.2 ± 15.9% after surgery (p < 0.01). All post-operative parameters except PI obtained statistically significant improvement after surgery. CONCLUSIONS: This is the first report of MCID of the 10 m walk velocity and TUG after ASD surgery. Ten meter walk velocity and the TUG improved after surgery; their improvement values were correlated with the ODI. MCID using the anchor-based approach for 10 m walk velocity and the TUG were 0.10 m/s and 2.0 s, respectively. These MCID values may be useful for rehabilitation after ASD surgery.

[Comparison of effectiveness between unilateral biportal endoscopic lumbar interbody fusion and endoscopic transforaminal lumbar interbody fusion for lumbar spinal stenosis combined with intervertebral disc herniation].

Objective: To compare the effectiveness between unilateral biportal endoscopic lumbar interbody fusion (ULIF) and endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) in treatment of lumbar spinal stenosis combined with intervertebral disc herniation. Methods: A clinical data of 64 patients with lumbar spinal stenosis and intervertebral disc herniation, who were admitted between April 2020 and November 2021 and met the selection criteria, was retrospectively analyzed. Among them, 30 patients were treated with ULIF (ULIF group) and 34 patients with Endo-TLIF (Endo-TLIF group). There was no significant difference in baseline data such as gender, age, disease duration, lesion segment, preoperative visual analogue scale (VAS) score of low back pain and leg pain, Oswestry disability index (ODI), spinal canal area, and intervertebral space height between the two groups ( P>0.05). The operation time, intraoperative blood loss, hospital stays, and postoperative complications were compared between the two groups, as well as the VAS scores of low back pain and leg pain, ODI, and imaging measurement indicators (spinal canal area, intervertebral bone graft area, intervertebral space height, and degree of intervertebral fusion according to modified Brantigan score). Results: Compared with the Endo-TLIF group, the ULIF group had shorter operation time, but had more intraoperative blood loss and longer hospital stays, with significant differences ( P<0.05). The cerebrospinal fluid leakage occurred in 2 cases of Endo-TLIF group and 1 case of ULIF group, and no other complication occurred. There was no significant difference in the incidence of complications between the two groups ( P>0.05). All patients in the two groups were followed up 12 months. The VAS scores of lower back pain and leg pain and ODI in the two groups significantly improved when compared with those before operation ( P<0.05), and there was no significant difference between different time points after operation ( P>0.05). And there was no significant difference between the two groups at each time point after operation ( P>0.05). Imaging examination showed that there was no significant difference between the two groups in the change of spinal canal area, the change of intervertebral space height, and intervertebral fusion rate at 6 and 12 months ( P>0.05). The intervertebral bone graft area in the ULIF group was significantly larger than that in the Endo-TLIF group ( P<0.05). Conclusion: For the patients with lumbar spinal stenosis combined with intervertebral disc herniation, ULIF not only achieves similar effectiveness as Endo-TLIF, but also has advantages such as higher decompression efficiency, flexible surgical instrument operation, more thorough intraoperative intervertebral space management, and shorter operation time.

TMEM100 Regulates Neuropathic Pain by Reducing the Expression of Inflammatory Factors.

There is no effective treatment for peripheral nerve injury-induced chronic neuropathic pain (NP), which profoundly impacts the quality of life of those affected. Transmembraneprotein100 (TMEM100) is considered to be a pain regulatory protein and is expressed in the dorsal root ganglion (DRG) of rats. However, the mechanism of pain regulation and the expression of TMEM100 following various peripheral nerve injuries are unclear. In this study, we constructed two pain models of peripheral nerve injury: tibial nerve injury (TNI) and chronic constriction injury (CCI). This study found that the Paw Withdrawal Mechanical Threshold (PWMT) and Paw Withdraw Thermal Latency (PWTL) of the rats in the two pain models decreased significantly, and the expression of TMEM100 in the DRG of two groups also decreased significantly. Furthermore, the decrease in the CCI group was more obvious than in the TNI group. There was no significant statistical significance (P > 0.05). We constructed an adeno-associated virus 6 (AAV6) vector expressing recombinant fluorescent TMEM100 protein and injected it into the sciatic nerve (SN) of two pain models: CCI and TNI. PWMT and PWTL were significantly increased in the two groups, along with the expression of TMEM100 in the spinal cord and DRG. It also significantly inhibited the activation of microglia, astrocytes, and several inflammatory mediators (TNF- α, IL-1 ß, and IL-6). In summary, the results of this study suggested that TMEM100 might be a promising molecular strategy for the treatment of NP, and its anti-inflammatory effects might play an important role in pain relief.

Zeolitic Imidazolate Framework (ZIF-8) Decorated Iron Oxide Nanoparticles Loaded Doxorubicin Hydrochloride for Osteosarcoma Treatment - in vitro and in vivo Preclinical Studies.

Background: As a broad-spectrum antitumorigenic agent, doxorubicin (DOX) is commonly used as a chemotherapeutic drug for treating osteosarcoma (OS). Still, it is associated with significant cell toxicity and ineffective drug delivery, whereas the zeolite imidazolate framework is extensively applied in the biomedical field as a carrier owing to its favorable biocompatibility, high porosity, and pH-responsiveness. Therefore, we need to develop a drug delivery platform that can effectively increase the antitumorigenic effect of the loaded drug and concurrently minimize drug toxicity. Methods: In this study, a Fe3O4@ZIF-8 nanocomposite carrier was prepared with ZIF-8 as the shell and encapsulated with Fe3O4 by loading DOX to form DOX- Fe3O4@ZIF-8 (DFZ) drug-loaded magnetic nanoparticles. Then, we characterized and analyzed the morphology, particle size, and characteristics of Fe3O4@ZIF-8 and DFZ by TEM, SEM, and Malvern. Moreover, we examined the inhibitory effects of DFZ in vitro and in vivo. Meanwhile, we established a tumor-bearing mouse model, evaluating its tumor-targeting by external magnetic field guidance. Results: DFZ nanoparticles possessed have a size of ~110 nm, with an encapsulation rate of 21% and pH responsiveness. DFZ exerted a superior cytostatic effect and apoptosis rate on K7M2 cells in vitro compared to DOX(p<0.01). In animal experiments, DFZ offers up to 67% tumor inhibition and has shown a superior ability to induce apoptosis than DOX alone in TUNEL results(p<0.01). Tumor-targeting experiments have validated that DFZ can be effectively accumulated in the tumor tissue and enhance anticancer performance. Conclusion: In summary, the DFZ nano-delivery system exhibited a more substantial anti-tumorigenic effect as well as superior active tumor targeting of DOX- Fe3O4@ZIF-8 compared to that of DOX alone in terms of biocompatibility, drug loading capacity, pH-responsiveness, tumor-targeting, and anti-tumorigenic effect, indicating its chemotherapeutic application potential.

Classification and Treatment for Cervical Spine Fracture with Ankylosing Spondylitis: A Clinical Nomogram Prediction Study.

Objective: Through the follow-up analysis of cervical spine fracture cases with ankylosing spondylitis (AS), a treatment-oriented fracture classification method is introduced to evaluate the clinical efficacy guided by this classification method. Method: A retrospective analysis was performed on 128 AS patients who underwent comprehensive treatment in the Spine Surgery Department of Qingdao University Hospital from January 2009 to May 2018. Statistics of patient demographic data, distribution of different fractures corresponding to surgical methods, 3-year follow-up outcomes, and summary of objective fracture classification methods were analyzed. A prospective 5-year follow-up study of 90 patients with AS cervical spine fractures from June 2015 to August 2020 was also included. Statistical differences on the distribution of factors such as case information, cervical spine sagittal sequence parameters, and fracture classification were assessed. Correlations between surgical information, American Spinal Injuries Association grade (ASIA), modified Japanese Orthopaedic Association scores (mJOA), and other factors were analyzed to establish a nomogram predictive model for curative effect outcomes. Overall, three major types and the four subtypes of AS cervical spine fractures were evaluated based on the clinical efficacy of the classification and the selection of surgical treatment methods. Result: The most common type of fracture was type II (30 cases, 33.33%), most of the subtypes were A (37 cases), followed by B (36 cases) and C (17 cases). Twenty-four of 28 patients with type I underwent anterior surgery, and 47 of 62 patients with type II and III underwent posterior surgery. The average follow-up time was 25.76 ± 11.80 months. The results of predicting clinical variables are different but include factors such as fracture type and subtype, type of operation, and age. The predictor variables include the above-mentioned similar variables, but survival is more affected by the fracture type of the patient. Conclusion: This predictive model based on follow-up information delineation points out the impact of ankylosing spondylitis cervical spine fracture classification on surgical selection and clinical efficacy.

Cervical Transdural Discectomy with Laminoplasty for the Treatment of Multi-segment Cervical Spinal Stenosis Accompanied with Cervical Disc Herniation: Technical Note and Clinical Outcome.

OBJECTIVE: To describe the surgical technique of cervical transdural discectomy with laminoplasty (CTDL) for the treatment of multi-segment cervical spinal stenosis (CSS) accompanied with cervical disc herniation (CDH) and investigate its surgical outcomes and complications. METHODS: This was a clinical study. Between 2012 and 2018, 31 patients (13 males and 18 females) with multi-segment CSS (over two cervical segments) accompanied with huge CDH and underwent CTDL were enrolled in this study. The details of CTDL technique with general anesthesia was described by the authors. The average follow-up period of patients was 65.03 months (range from 24 to 126 months). Perioperative parameters such as age, sex, operative level, operative time, estimated blood loss, ambulation time, and operative complications were recorded. The results of clinical metrics such as the visual analog scale (VAS) and Japanese Orthopaedic Association (JOA) scores in the preoperative and during the follow-up period were obtained and used to evaluate clinical outcomes. Radiographic improvement was evaluated by the compression ratio, sagittal maximum spinal cord compression (SMSCC), and cervical range of motion (ROM). The preoperative and postoperative follow-up parameters (VAS, JOA, Compression ratio, SMSCC, and ROM) were assessed with paired t test. A P-value <0.05 was considered statistically significant. RESULTS: In the study, the mean age of the 31 patients was 55.23 ± 10.97 years. The mean operative time was 192.45 ± 24.17 min (ranging from 150 to 245 min), and intraoperative blood loss was 322.58 ± 129.00 mL (ranging from 150 to 600 mL). The VAS neck pain was improved significantly over the follow-up period (P < 0.05, respectively). The VAS arm pain improved significantly from 6.26 ± 0.93 preoperatively to 1.74 ± 0.63 at 24 months postoperatively (P < 0.001). There was no significant difference in improvement of VAS arm pain between 24 months postoperatively and final follow-up (P = 0.180). Compared with preoperative JOA score, JOA score was significantly improved at 24 months postoperatively (14.79 ± 1.84 vs 9.66 ± 2.81, P < 0.001). Meanwhile, there were no statistically significant differences between the final follow-up and the postoperative JOA scores (15.08 ± 1.71 vs 14.79 ± 1.84, P = 0.051). Postoperative patients showed significantly higher index of compression ratio (58.30 ± 8.51 vs 27.17 ± 3.89, P < 0.001) and lower SMSCC (25.12 ± 5.67 vs 33.66 ± 5.38, P < 0.001). In addition, there was no significant difference between preoperative and postoperative cervical ROM (P = 0.740). One patient observed postoperative symptom of C6 nerve root injury, which was resolved within 24 months after the surgery; meanwhile, the neurological monitoring also reflected the intraoperative stretching of the C6 nerve root. Two cases involved postoperative cerebrospinal fluid (CSF) leakage which may have been related to laceration of dura mater. CONCLUSIONS: This study suggested that CTDL technique could acquire satisfactory surgical outcomes for patients with multi-segment CSS accompanied with CDH, but the surgical indications of the patients need to be selected strictly.

Suppression of CRLF1 promotes the chondrogenic differentiation of bone marrow-derived mesenchymal stem and protects cartilage tissue from damage in osteoarthritis via activation of miR-320.

BACKGROUND: Osteoarthritis (OA) is the most prevalent chronic joint disease, and is hard to be cured at present. Cytokine receptor-like factor 1 (CRLF1) has been identified as an upregulated gene in OA cartilage. However, the precise identities and functions of CRLF1 in OA progression have remained to be fully elucidated. METHODS: We used a murine model of injury-induced OA (destabilization of medial meniscus, DMM) and BMSCs to investigate the specific biological functions and mechanisms of CRLF1. RESULTS: We found that CRLF1 was significantly increased in the DMM surgery-induced OA model and was down-regulated during chondrogenic differentiation of BMSCs. Luciferase reporter assays showed that CRLF1 was a direct target of miR-320 in BMSCs. miR-320 can reverse the effect of CRLF1 on cell proliferation, apoptosis and chondrogenic differentiation of BMSCs. Furthermore, knockdown of CRLF1 or over-expression of miR-320 can inhibit the apoptosis of primary chondrocytes. CONCLUSION: Suppression of CRLF1 promotes the chondrogenic differentiation of BMSCs and protects cartilage tissue from damage in osteoarthritis via activation of miR-320.

Elevated lymphotoxin-α (TNFß) is associated with intervertebral disc degeneration.

BACKGROUND: Intervertebral disc degeneration (IVDD) is a primary cause of degenerative disc diseases; however, the mechanisms underlying the degeneration remain unclear. The immunoinflammatory response plays an important role in IVDD progression. The inflammatory cytokine lymphotoxin-α (LTα), formerly known as TNFß, is associated with various pathological conditions, while its role in the pathogenesis of IVDD remains elusive. METHODS: Real-time quantitative polymerase chain reaction (RT-qPCR), Western blotting (WB), and enzyme-linked immunosorbent assays were used to assess the levels of LTα in human nucleus pulposus (NP) tissues between degeneration and control groups. The plasma concentrations of LTα and C-reactive protein (CRP) were compared between healthy and IVDD patients. Rat primary NP cells were cultured and identified via immunofluorescence. Methyl-thiazolyl-tetrazolium assays and flow cytometry were used to evaluate the effects of LTα on rat NP cell viability. After NP cells were treated with LTα, degeneration-related molecules (Caspase-3, Caspase-1, matrix metalloproteinase (MMP) -3, aggrecan and type II collagen) were measured via RT-qPCR and WB. RESULTS: The levels of both the mRNA and protein of LTα in human degenerated NP tissue significantly increased. Plasma LTα and CRP did not differ between healthy controls and IVDD patients. Rat primary NP cells were cultured, and the purity of primary NP cells was > 90%. Cell experiments showed inversely proportional relationships among the LTα dose, treatment time, and cell viability. The optimal conditions (dose and time) for LTα treatment to induce rat NP cell degeneration were 5 µg/ml and 48 ~ 72 h. The apoptosis rate and the levels of Caspase-3, Caspase-1, and MMP-3 significantly increased after LTα treatment, while the levels of type II collagen and aggrecan were decreased, and the protein expression levels were consistent with their mRNA expression levels. CONCLUSIONS: This study demonstrated that elevated LTα is closely associated with IVDD and that LTα may induce NP cell apoptosis and reduce important extracellular matrix (ECM) proteins, which cause adverse effects on IVDD progress. Moreover, the optimal conditions for LTα treatment to induce NP cell degeneration were determined.

MNAT1 promotes proliferation and the chemo-resistance of osteosarcoma cell to cisplatin through regulating PI3K/Akt/mTOR pathway.

BACKGROUND: MNAT1 (menage a trois 1, MAT1), a cyclin-dependent kinase-activating kinase (CAK) complex, highly expressed in diverse cancers and was involved in cancer molecular pathogenesis. However, its deliverance profile and biological function in osteosarcoma (OS) remain unclear. METHODS: The expression of MNAT1 in OS was detected by western blot (WB) and immunohistochemistry (IHC). The potential relationship between MNAT1 molecular level expression and OS clinical expectations were analyzed according to tissues microarray (TMA). Proliferation potential of OS cells was evaluated in vitro based on CCK8 and OS cells colony formation assays, while OS cells transwell and in situ tissue source wound healing assays were employed to analyze the OS cells invasion and migration ability in vitro. A nude mouse xenograft model was used to detect tumor growth in vivo. In addition, ordinary bioinformatics analysis and experimental correlation verification were performed to investigate the underlying regulation mechanism of OS by MNAT1. RESULTS: In this research, we found and confirmed that MNAT1 was markedly over-expressed in OS tissue derived in situ, also, highly MNAT1 expression was closely associated with bad clinical expectations. Functional studies had shown that MNAT1 silencing could weaken the invasion, migration and proliferation of OS cells in vitro, and inhibit OS tumor growth in vivo. Mechanism study indicated that MNAT1 contributed to the progression of OS via the PI3K/Akt/mTOR pathway. We further verified that the MNAT1 was required in the regulation of OS chemo-sensitivity to cisplatin (DDP). CONCLUSIONS: Taken together, the data of the present study demonstrate a novel molecular mechanism of MNAT1 involved in the formation of DDP resistance of OS cells.

Histologic Observation and Significance of Sympathetic Nerve Fiber Distribution on Human Cervical Ligamentum Flavum.

OBJECTIVE: To study the distribution of sympathetic nerves of the ligamentum flavum (LF), confirm its existence by histological observation and nuclear magnetic resonance spectroscopy, and analyze the relationship between sympathetic nerve fibers and the biomechanical structure of the LF. METHODS: Randomly controlled scientific research selected 15 cases of posterior surgery in the affiliated hospital of Qingdao University from January 2013 to December 2019. The average age was 67.5 ± 14.5 years old, eight males and seven females. The LF specimens (completely separated fresh tissue) of different segments (C3-7 ) were taken during the operation. Two pages of LF specimens on the left and right sides of the same segment are randomly allocated by the pairing method for formalin fixation and cryopreservation in liquid nitrogen. LF specimens extracted from seven other adult cadaver specimens (average age at death of about 56.8 ± 4.0 years, three males and four females) were used as a control group; together with formalin- fixed specimens obtained during surgery, 3D slices were given layer by layer. The distribution of sympathetic nerves in different parts of the LF was analyzed by glyoxylic acid-induced biological monoamine fluorescent technique (SPG) and hematoxylin-eosin (HE) staining. Fifteen liquid nitrogen storage specimens were divided into the back of the LF and the spinal canal through frozen sections, and were analyzed by nuclear magnetic resonance spectroscopy-hydrogen spectrum (1 H -NMR) for neurotransmitters and neurometabolites. RESULTS: There were type C sympathetic nerve fibers in the LF, which were divided into linear shape (α) and wave shape (ß). Experimental group (χ2 = 1.705, P > 0.05) and control group (χ2 = 0.879, P > 0.05) can detect no difference in fluorescence units. Nerve fiber transmitter metabolites choline (Cho), creator (Cr), γ-aminobutyric acid (GABA) also indicate that the sympathetic nerve is present in the LF. LF sympathetic nerve fibers were mainly distributed in the proximal spinal canal surface, nerve fibers on the medial belt (area II) were fewer than the lateral belt (area I) (W = 210, P < 0.05). The 1 HNMR spectrum of LF spinal canal PG / Cho (t = 8.721, P < 0.05), GABA (t = 16.01, P < 0.05) value increased, lactic acid (Lac) / Cr (t = 4.213, P < 0.05), Cho / Cr (t = 2.402, P < 0.05) value decreased, indicating that nerve fibers are actively metabolized on the surface of the spinal canal, mainly distributed in tube surface. ßtype fibers were more often distributed around microvessels. A small amount of α type fibers went next to the vascular structures, while α type fibers and ß type fibers go cross within LF. Two patients with vertebral artery dissection had no recurrence of sympathetic symptoms within a total of 12 follow-ups 2 years after discharge. CONCLUSIONS: There are many sympathetic nerve fibers distributed on LF, and their distribution may be correlated with histological and mechanical characteristics of LF. It may also be the anatomical basis of cervical vertigo.

ADAMTS7 degrades Comp to fuel BMP2-dependent osteogenic differentiation and ameliorate oncogenic potential in osteosarcomas.

Osteosarcoma (OS) is the most common primary malignant bone tumor in children and adolescents, with a high metastatic potential. Despite dramatic changes in OS treatments over the past decades, their efficiency still remains limited, with severe complications and adverse side effects. Key mechanisms underlining tumorigenesis, metastasis and chemotherapy resistance are currently lacking, in turn hindering any progress with respect to developing effective and safe therapeutic strategies against OS. Recently, ADAMTS7, a member of the disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) family, was shown to be involved in osteogenic differentiation-related pathological processes. ADAMTS7 promotes vascular calcification via disturbing the balance between osteogenic bone morphogenetic protein (BMP)2 (regulating osteogenic differentiation and bone formation during development) and its natural inhibitor cartilage oligomeric matrix protein (Comp). Hence, in the present study, we aimed to investigate the role of ADAMTS7 in the pathological process of OS. We first revealed that ADAMTS7 was decreased in OS tissues. Lower expression of ADAMTS7 was correlated with poor histological differentiation and an advanced clinical stage of OS. Through loss- and gain-function analysis, we further revealed that ADAMTS7 attenuated cell proliferation, migration and invasion, at the same time as promoting the expression of osteogenic differentiation markers in two OS cell lines: MG63 and SAOS2. Moreover, Comp was responsible for the effects of ADAMTS7 on OS pathogenesis by reinforcing cell osteogenic differentiation mediated by BMP2 in vitro. In conclusion, ADAMTS7-mediated degradation of Comp may provide a potential therapeutic target for the treatment of OS.

Exosomes Secreted by Adipose-Derived Mesenchymal Stem Cells Foster Metastasis and Osteosarcoma Proliferation by Increasing COLGALT2 Expression.

OBJECTIVES: Homosapien collagen beta (1-O) galactosyl transferase 2 (COLGALT2) is an important enzyme during collagen glycosylation, yet its biological functions in cancer are incompletely understood. Our previous study revealed that in the osteosarcoma microenvironment, adipose-derived mesenchymal stem cells (ADSCs) demonstrate cancer-promoting effects, but the exact mechanisms remain unclear. The aim of this study was to investigate the role of COLGALT2 in the osteosarcoma-fostering effects of ADSCs. MATERIALS AND METHODS: In this study, we compared COLGALT2 expression between primary and metastatic osteosarcoma tissues and found that metastatic tissues expressed significantly higher COLGALT2 levels. Then, we isolated and identified exosomes secreted by ADSCs. Additionally, we assessed the roles of ADSC exosomes and COLGALT2 in the osteosarcoma-promoting effects of ADSCs. RESULTS: Our results showed that ADSC exosomes could foster the invasion, migration, and proliferation of osteosarcoma cells, together with increasing COLGALT2 expression. COLGALT2 inhibition in MG63 cells suppressed the ADSC exosome-mediated fostering of osteosarcoma cell invasion, migration and proliferation in vitro. Conversely, COLGALT2 overexpression promoted U-2OS cell invasion, migration and proliferation in vitro. Additionally, COLGALT2 inhibition attenuated metastasis and tumor growth, and ADSC exosomes promoted tumor progression, as demonstrated in a nude mouse model of osteosarcoma. CONCLUSION: According to these data, ADSC exosomes foster osteosarcoma progression by increasing COLGALT2 expression in osteosarcoma cells.

PLOD1, a target of miR-34c, contributes to cell growth and metastasis via repressing LATS1 phosphorylation and inactivating Hippo pathway in osteosarcoma.

Although dysregulated PLOD1 was reported in many cancers, its function in osteocarcoma (OS) progression and potential mechanism are totally unknown. In the present study, we found that the mRNA expression of PLOD1 was significantly upregulated in OS cells and tissues. The high expression of PLOD1 was correlated with the aggressive phenotypes of OS and poor prognosis. Gain- or loss-of-function assays demonstrated that PLOD1 promoted proliferation, migration, and invasion of OS cells in vitro, as well as tumorigenicity and metastasis in vivo. We found that PLOD1 inactivated Hippo-YAP pathway through inhibiting phosphorylation-LATS1 (p-LATS1) and -YAP (p-YAP). Immunofluorescence results validated that nuclear distribution of YAP was increased by PLOD1 overexpression and was decreased by PLOD1 depletion. Furthermore, PLOD1 was demonstrated as a target of miR-34c, which inhibited the luciferase activity of PLOD1 mRNA 3'-UTR and PLOD1 expression at both mRNA and protein levels. The expression of miR-34c was downregulated in OS tissues and negatively correlated with PLOD1 mRNA expression. We found that restoration of PLOD1 abolished the miR-34c induced inhibition of cell growth and invasion. More importantly, miR-34c led to upregulation of p-LATS1 and p-YAP, and reducing of nuclear YAP and TAZ in OS cells. The mice tumors, which formed from miR-34c lentivirus vectors, have relatively low expression of PLOD1 and nuclear YAP staining. Taken together, our findings revealed that PLOD1 promoted tumorigenesis and metastasis in OS, and the dysregulated miR-34c/PLOD1/Hippo pathway affected OS progression, providing a potential therapeutic strategy for treatment.

Three-dimensional porous composite scaffolds for in vitro marrow microenvironment simulation to screen leukemia drug.

The traditional 2D culture medium used for simulating the in vitro microenvironment for leukemia cells usually leads to 95% of the drug test results being different to the subsequent clinical results. Unlike this 2D culture, 3D scaffolds are more similar to the bone marrow microenvironment so can better simulate the drug effect on leukemia cells, which can benefit the preliminary screening of drugs for clinical use. For this purpose, the freeze-drying method was proposed for the fabrication of 3D scaffolds of graphene oxide/silk fibroin/carboxymethyl chitosan (GO/SF/CMCS). Experimental results show that these 3D scaffolds exhibit a better swelling ratio because of the embedding of GO. The improved hydrophilicity of the scaffolds brings about promoted adhesion and proliferation of leukemia cells. In contrast to the traditional 2D culture, leukemia cells in this 3D culture show stronger drug resistance, which is consistent with the previously reported clinical results. It implies that these 3D GO/SF/CMCS scaffolds can simulate well the in vivo bone marrow microenvironment, making it a promising platform for preliminary drug screening for clinical use.

Adeno-associated virus packaged TRPC5 gene therapy alleviated spinal cord ischemic reperfusion injury in rats.

Spinal cord injury (SCI) is a devastating disease with few effective treatments. This study mainly explored the mechanism of TRPC5 gene in the treatment of spinal cord ischemia reperfusion injury from the perspective of angiogenesis. Western blot, immunohistochemistry, hematoxylin and eosin, ELISA, and reverse transcription-PCR (RT-PCR) were used to detect the expression levels of related angiogenic proteins such as von Willebrend factor (vWF), vascular endothelial growth factor (VEGF), CD31, and HIF-1α. The results showed that compared with the IR group, the Basso, Beattie, and Bresnahan scores of IR + adeno-associated virus (AAV) + TRPC5 group were higher with significant difference. And compared with ischemia/reperfusion (I/R) group, RT-PCR and ELISA results showed that inflammatory factors such as IL-6, IL-1ß, and TNF-α were significantly reduced in IR + AAV + TRPC5 group. In addition, the expression of vascular related proteins such as vWF, VEGF, and CD31 in spinal cord tissue were all increased. Taken together the results, we suggest that TRPC5 could significantly increase the expression of angiogenic protein and slow down the occurrence of inflammatory response to repair the SCI.

Epidural adipose tissue-derived mesenchymal stem cell activation induced by lung cancer cells promotes malignancy and EMT of lung cancer.

BACKGROUND: Spinal metastasis is a major challenge in patients with advanced lung cancer, but the mechanisms in the organotropism of metastasis are still unclear. Adipose-derived mesenchymal stem cells (ADSCs) exhibit cancer-promoting properties that influence the tumour microenvironment; however, there is no research on ADSCs from epidural fat thus far. METHODS: In this study, we isolated and identified ADSCs from epidural adipose tissue for the first time. We examined the activation of epidural ADSCs treated with lung cancer cell-conditioned medium by immunohistochemistry, western blot and qRT-PCR assays. The expression of interleukin (IL)-6 family cytokines in the supernatants of ADSCs were evaluated by enzyme-linked immunosorbent assay. The effects of epidural ADSCs on the growth and invasion of lung cancer cells were evaluated with the CCK-8 and Transwell assays. The expression of signal transducer and activator of transcription 3 (STAT3), matrix metalloprotease and epithelial-mesenchymal transition markers were measured by western blot assays. RESULTS: Our results showed that ADSCs treated with lung cancer cell-conditioned medium expressed higher levels of the myofibroblast marker α-smooth muscle actin and fibroblast activation protein than ADSCs cultured alone. Then, we found that lung cancer cells induced ADSCs to secrete high levels of IL-6 family cytokines and activate the STAT3 signalling pathway. Moreover, activated epidural ADSCs exhibited the ability to promote lung cancer cell proliferation and invasion by elevating matrix metalloprotease expression and epithelial-mesenchymal transition in cancer cells. Furthermore, blocking IL-6 can counteract the differentiation and tumour-promoting effects of ADSCs. CONCLUSION: Our results suggest that ADSCs respond to lung cancer cells and are involved in the crosstalk between primary tumours and pre-metastatic niches in epidural fat.

AAV-encoded CaV2.2 peptide aptamer CBD3A6K for primary sensory neuron-targeted treatment of established neuropathic pain.

Transmission of pain signals from primary sensory neurons to secondary neurons of the central nervous system is critically dependent on presynaptic voltage-gated calcium channels. Calcium channel-binding domain 3 (CBD3), derived from the collapsin response mediator protein 2 (CRMP2), is a peptide aptamer that is effective in blocking N-type voltage-gated calcium channel (CaV2.2) activity. We previously reported that recombinant adeno-associated virus (AAV)-mediated restricted expression of CBD3 affixed to enhanced green fluorescent protein (EGFP) in primary sensory neurons prevents the development of cutaneous mechanical hypersensitivity in a rat neuropathic pain model. In this study, we tested whether this strategy is effective in treating established pain. We constructed AAV6-EGFP-CBD3A6K (AAV6-CBD3A6K) expressing a fluorescent CBD3A6K (replacing A to K at position 6 of CBD3 peptide), which is an optimized variant of the parental CBD3 peptide that is a more potent blocker of CaV2.2. Delivery of AAV6-CBD3A6K into lumbar (L) 4 and 5 dorsal root ganglia (DRG) of rats 2 weeks following tibial nerve injury (TNI) induced transgene expression in neurons of these DRG and their axonal projections, accompanied by attenuation of pain behavior. We additionally observed that the increased CaV2.2α1b immunoreactivity in the ipsilateral spinal cord dorsal horn and DRG following TNI was significantly normalized by AAV6-CBD3A6K treatment. Finally, the increased neuronal activity in the ipsilateral dorsal horn that developed after TNI was reduced by AAV6-CBD3A6K treatment. Collectively, these results indicate that DRG-restricted AAV6 delivery of CBD3A6K is an effective analgesic molecular strategy for the treatment of established neuropathic pain.

Unique Complications of Percutaneous Endoscopic Lumbar Discectomy and Percutaneous Endoscopic Interlaminar Discectomy.

BACKGROUND: Percutaneous endoscopic discectomy (PED) includes 2 main procedures: percutaneous endoscopic lumbar discectomy (PELD) and percutaneous endoscopic interlaminar discectomy (PEID), both of which are minimally invasive surgical procedures that effectively deal with lumbar degenerative disorders. Because of the challenging learning curve for the surgeon and the individual characteristics of each patient, preventing and avoiding complications is difficult. The most common complications, such as nucleus pulposus omission, nerve root injury, dural tear, visceral injury, nerve root induced hyperalgesia or burning-like nerve root pain, postoperative dysesthesia, posterior neck pain, and surgical site infection, are difficult to avoid; however, more focus on these issues perioperatively may be in order. Additionally, unique and unexpected complications can also occur, such as retroperitoneal hematoma (RPH), intraoperative seizures, and thrombophlebitis, among others. OBJECTIVE: We aim to delineate unique complications during PED and accumulate strategies to prevent significant morbidity and improve surgical techniques. STUDY DESIGN: A retrospective cohort study of patients undergoing PEID or PELD from October 2014 to January 2016. SETTING: Affiliated hospitals of Qingdao University. METHODS: Patients with lumbar disc herniation (LDH) who underwent PEID and PELD were retrospectively analyzed. Complications were recorded and analyzed pre and postoperatively. We assessed clinical outcomes using the visual analog scale (VAS) and Oswestry Disability Index (ODI) and classified the results into "excellent," "good," "fair," or "poor" based on the modified MacNab criteria. All of the patients were followed for more than one year to evaluate their recovery from complications. RESULTS: From October 2014 to January 2016, 426 patients with LDH underwent PEID (106 cases) or PELD (320 cases). Common complications and occurrence rates were as follows: the incomplete removal of herniated discs was 1.4% (6/426), recurrence 2.8% (12/426), nerve root injury 1.2% (5/426), dural tear 0.9% (4/426), and nerve root induced hyperalgesia or burning-like nerve root pain 2.3% (10/426); no posterior neck pain or surgical site infection occurred. Unique complications included: passage of the working channel through the spinal canal into the disc space (one case), super-elastic nerve hook caught by exiting nerve root (one case), epidural hematoma (one case), radicular artery injury and massive bleeding (one case) which was revised by micro-endoscopic discectomy, and intraoperative seizure (one case). No serious consequences occurred after active medical intervention, and most patients had good recovery by 3 months postoperatively with physical therapy. LIMITATIONS: The main limitations of this study are the retrospective study design, limited case number, and short follow-up period. CONCLUSIONS: PEDs are effective and minimally invasive methods for the surgical treatment of LDH, causing fewer complications due to the very minimal operational trauma for the muscle-ligament complex and stability of the spine. Nevertheless, because of the difficult learning curve for surgeons, lack of experience with the requisite surgical techniques, and enhanced clinical responsibility, a variety of problems may occur. Especially concerning are the unique complications mentioned here, which potentially lead to severe injury for the patient and require diligent preventive measures. KEY WORDS: Unique complications, epidural, hematoma, interlaminar, transforaminal, PEID, PELD.