WITHDRAWN: Clinical Efficacy of Early Microsurgical Clipping of Tumor Neck in the Treatment of Cerebral Aneurysm Rupture and Bleeding and Its Impact on Oxidative Stress Response and Prognosis of Patients.

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Clinical efficacy of early microsurgical clipping of tumor neck in the treatment of cerebral aneurysm rupture and bleeding and its impact on oxidative stress response and prognosis of patients.

Cerebral aneurysm can rupture a blood vessel and cause bleeding in the brain. Microsurgical clipping of the tumor neck has been reported to be effective in treating cerebral aneurysm rupture and bleeding. This research attempted to clarify the clinical efficacy of early microsurgical clipping of tumor neck for treating cerebral aneurysm rupture and bleeding, and its impact on the prognosis of patients. One hundred patients with cerebral aneurysm rupture and bleeding patients were treated. They were selected and divided into experimental group (n=25) and control group (n=25) according to surgical time. All patients underwent microsurgical clipping of tumor neck for therapy. The control group chose to undergo surgery 72 hours after the onset of cerebral aneurysm rupture and bleeding, while the experimental group chose to undergo complete surgery within 72 hours after the onset of cerebral aneurysm rupture and bleeding. Primary outcome measures were incidence of complications, cognitive function scores, prognosis, surgical indicators, oxidative stress response and quality of life. Results showed that compared to the control group, the incidence of complications in experimental group exhibited depletion (P<0.05), the prognosis in experimental group exhibited elevation (P<0.05), the hospitalization time in experimental group exhibited depletion (P<0.05), the nomination, abstraction, language, orientation, attention, delayed recall and visual and executive function scores and total scores in experimental group exhibited elevation (P<0.05), serum levels of oxidative stress-related indicators in experimental group exhibited depletion (P<0.05) and the quality of life in experimental group exhibited elevation (P<0.05). In conclusion, early microsurgical clipping of the tumor neck can reduce the risk of complications and cognitive impairment in patients with cerebral aneurysm rupture and bleeding.

"Early Efficacy and Safety of Unilateral Biportal Endoscopic Lumbar Interbody Fusion Versus Minimal Invasive in the Treatment of Lumbar Degenerative Diseases".

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: To compare the early clinical efficacy and radiologic outcomes between unilateral biportal endoscopic lumbar interbody fusion (ULIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). SUMMARY OF BACKGROUND DATA: Along with the continuous development of endoscopic technology, the early safety and effectiveness of ULIF technology are still unknown. MATERIALS AND METHODS: This retrospective study included 61 patients who underwent fusion surgery through ULIF or MIS-TLIF in 2021. Twenty-nine patients underwent ULIF (group A), and 32 underwent MIS-TLIF (group B). Fusion rate, bone graft volume, hidden blood loss (HBL), C-reactive protein level, operative time, Oswestry Disability Index , Visual Analog Scale score, and MacNab criteria were assessed in both groups. RESULTS: The Visual Analog Scale score for back pain in the early postoperative period was significantly lower in group A than in group B ( P <0.05). All other clinical scores showed improvement, with no significant difference between the 2 groups ( P >0.05). There was no statistically significant difference in postoperative C-reactive protein levels and fusion rates between the 2 groups ( P >0.05). However, HBL was higher and operative time was longer in group A than in group B ( P <0.05). Most importantly, there were no statistically significant differences between groups A and B in fusion rate, length of stay and bone graft volume ( P >0.05). No serious surgical complications occurred in our study. CONCLUSIONS: ULIF is a new option for lumbar fusion. Despite the drawbacks of longer operation time and higher HBL, ULIF may be a viable alternative to MIS-TLIF as technology advances.

[Treatment of stage â ¡-â ¢ Kümmell disease with robot-assisted bone cement-augmented pedicle screw fixation].

OBJECTIVE: To evaluate the early clinical efficacy of robot-assisted percutaneous short-segment bone cement-augmented pedicle screw fixation in the treatment of stageⅡ-Ⅲ Kümmell disease. METHODS: The clinical data of 20 patients with stageⅡ-Ⅲ Kümmell's disease who underwent robot-assisted percutaneous bone cement-augmented pedicle screw fixation between June 2017 and January 2021 were retrospectively analyzed. There were 4 males and 16 females, aged from 60 to 81 years old with an average age of (69.1±8.3) years. There were 9 cases of stageⅡand 11 cases of stage Ⅲ, all of which were single vertebral lesions, including 3 cases of T11, 5 cases of T12, 8 cases of L1, 3 cases of L2, and 1 case of L3. These patients did not exhibit symptoms of spinal cord injury. The operation time, intraoperative blood loss, and complications were recorded. The position of pedicle screws and the filling and leakage of bone cement in gaps were observed using postoperative CT 2D reconstruction. The data of the visual analogue scale (VAS), Oswestry disability index (ODI), kyphosis Cobb angle, wedge angle of the diseased vertebra, and anterior and posterior vertebral height on lateral radiographs were statistically analyzed preoperatively, 1 week postoperatively, and at the final follow-up. RESULTS: Twenty patients were followed up for 10 to 26 months, with an average follow-up of (16.0±5.1) months. All operations were successfully completed. The surgical duration ranged from 98 to 160 minutes, with an average of (122±24) minutes. The intraoperative blood loss ranged from 25 to 95 ml, with an average of (45±20) ml. There were no intraoperative vascular nerve injuries. A total of 120 screws were inserted in this group, including 111 screws at grade A and 9 screws at grade B according to the Gertzbein and Robbins scales. Postoperative CT indicated that the bone cement was well-filled in the diseased vertebra, and cement leakage occurred in 4 cases. Preoperative VAS and ODI were (6.05±0.18) points and (71.10±5.37)%, respectively, (2.05±0.14) points and (18.57±2.77)% at 1 week after operation, and (1.35±0.11) points and (15.71±2.12) % at final follow-up. There were significant differences between postoperative 1 week and preoperative, and between final follow-up and postoperative 1 week(P<0.01). Anterior and posterior vertebral height, kyphosis Cobb angle, and wedge angle of the diseased vertebra were(45.07±1.06)%, (82.02±2.11)%, (19.49±0.77) °, and (17.56±0.94) ° preoperatively, respectively, (77.00±0.99)%, (83.04±2.02)%, (7.34±0.56) °, and (6.15±0.52) ° at 1 week postoperatively, and (75.13±0.86)%, (82.39±0.45)%, (8.38±0.63) °, and (7.09±0.59) ° at the final follow-up. CONCLUSION: Robot-assisted percutaneous short-segment bone cement-augmented pedicle screw fixation demonstrates satisfactory short-term efficacy in treating stageⅡ-Ⅲ Kümmell's disease as an effective minimally invasive alternative. However, longer operation times and strict patient selection criteria are necessary, and long-term follow-up is required to determine its lasting effectiveness.

A comparative study of robot-assisted and traditional surgeries in the treatment of thoracolumbar fractures based on 1-year follow-up observation.

BACKGROUND: There are conflicting results for robot-assisted (RA) pedicle screw fixation compared with freehand (FH) pedicle screw fixation. OBJECTIVE: This study was designed to retrospectively compare the accuracy and efficacy of RA percutaneous pedicle screw fixation and traditional freehand FH pedicle screw fixation in the treatment of thoracolumbar fractures. METHODS: A total of 26 cases were assigned to the RA group, and 24 cases were assigned to the FH group. The operation time, bleeding volume, and visual analog scale (VAS) score 1 day after the operation, and the anterior/posterior (A/P) vertebral height ratio of the injured vertebrae at 3 days and at internal fixation removal 1 year after the operation were compared between the two groups. Pedicle screw position accuracy was assessed according to Gertzbein criteria. RESULTS: The operation times of the RA group and FH group were 138.69 ± 32.67 minutes and 103.67 ± 14.53 minutes, respectively, and the difference was statistically significant. The intraoperative blood loss was 49.23 ± 22.56 ml in the RA group and 78.33 ± 23.90 ml in the FH group, and the difference was statistically significant. There was a significant difference in the A/P vertebral height ratio of the injured vertebrae 3 days after the operation compared with before the operation in both groups (P < 0.05). There was a significant difference in the A/P vertebral height ratio of the injured vertebrae 3 days after the operation compared with that at fixation removal in both groups (P < 0.05). CONCLUSION: The application of RA orthopedic treatment for thoracolumbar fractures can achieve good fracture reduction.

A comparative study of PSPVP and PSIBG in the treatment of stage II-III Kummell's disease.

BACKGROUND: Percutaneous kyphoplasty (PKP) or percutaneous vertebroplasty (PVP) are commonly employed for Kummell's disease in stages II-III; however, these techniques produce some complications. OBJECTIVE: To compare the clinical efficacy and imaging results of percutaneous vertebroplasty + bone cement-augmented short-segment pedicle screw fixation (PSPVP) versus transpedicular intracorporeal bone grafting + pedicle screw fixation (PSIBG) in the treatment of stage II-III Kummell's disease. METHODS: A total of 69 patients admitted between November 2017 and March 2021 were included in this study; 36 of these were treated with PSPVP, and 33 were treated with PSIBG. Patients in the two groups were compared in terms of perioperative, follow-up, and imaging data. RESULTS: No statistically significant differences were found between the two groups in terms of operation duration (P > 0.05). However, the PSPVP group was superior to the PSIBG group in terms of incision length, intraoperative blood loss, and length of stay (P < 0.05). All patients were followed up for more than 12 months. The VAS score, height of anterior vertebral margin, kyphosis Cobb angle, wedge angle of the affected vertebra at seven days after surgery and last follow-up, and the ODI index at the last follow-up of the two groups were significantly improved compared with figures before surgery (P < 0.05). Compared with values before surgery, no statistically significant differences were found in the height of the posterior vertebral margin in the PSPVP group at seven days after surgery and at the last follow-up (P > 0.05). There were also no statistically significant differences in the VAS score, ODI index, kyphosis Cobb angle, and wedge angle of the affected vertebra between the two groups at corresponding time points (P > 0.05). The heights of the anterior and posterior vertebral margins in the PSIBG group were better than those in the PSPVP group after surgery and at the last follow-up (P < 0.05). In the PSPVP group, a pedicle screw fracture occurred in one patient two months after surgery, while an upper adjacent vertebral fracture occurred in one patient eight months after surgery. CONCLUSION: Both PSPVP and PSIBG can achieve good early clinical efficacy in the treatment of stage II-III Kummell's disease, with PSPVP being relatively less invasive while producing a poorer orthopedic effect and more complications than PSIBG.

Confirmation value of Western blotting in detecting anti-treponema pallidum specific antibodies with suspicious results.

BACKGROUND: Due to the inconsistent results of anti-treponema pallidum (TP) specific antibodies by enzyme-linked immunosorbent assay (ELISA) and Treponema pallidum granule agglutination assay (TPPA) in clinical work, there will be a certain proportion of false-positives and false-negatives depending on TPPA as confirmation results. This study aimed to evaluate the necessity of Western blotting (WB) in samples with inconsistent results in detecting anti-TP antibodies by ELISA and TPPA. METHODS: Specific anti-TP test results in our clinical laboratory were retrospectively analyzed. The specimens with a positive or a negative result, but with colored ELISA plates, were retested by TPPA. WB was used to confirm the suspicious results between ELISA and TPPA. The Chi-square test was used to analyze whether the difference was statistically significant. RESULTS: A total of 106,757 anti-TP specimens were screened by ELISA from August 2018 to December 2019; 3972 were retested by TPPA, and 3809 were positive by TPPA. ELISA and TPPA showed different results in 163 specimens. Among them, 29 specimens were negative and 134 were positive by ELISA; 76 were negative, 23 were positive, and 64 were "reserve" by TPPA; 93 were negative, 31 were positive, and 39 were suspicious by the WB confirmation test. Compared with WB, the difference in the results of ELISA and TPPA was statistically significant. CONCLUSIONS: TPPA is an effective retest method for anti-TP antibody detection. If the results of anti-TP antibodies by ELISA and TPPA are inconsistent, it is necessary to use WB for confirmation. Trial registration This retrospective analysis is in accordance with the ethical guidelines of China and approved by the second hospital of Jiaxing (jxey-2018048).

Percutaneous Transforaminal Endoscopic Decompression for Lumbar Lateral Recess Stenosis.

Objective: The aim of this study was to evaluate the treatment efficacy of lateral spinal stenosis through the decompression of the nerve root under a multiple planar endoscope. Methods: From January 2017 to March 2019, 52 patients with lumbar spinal stenosis or lumbar spinal stenosis combined with intervertebral disc herniation had been treated via transforaminal approach spinal endoscopy. Our study retrospectively analyzed the treatment outcome. All patients experienced complications with different degrees of facet joint hyperplasia and ligamentum flavum hyperplasia and hypertrophy. Some patients suffered disc herniation. All patients were treated with percutaneous transforaminal approach multiple planar endoscopic decompression. The visual analog scale (VAS) and the Oswestry Disability Index (ODI) were compared before and after the operation, as were the horizontal foramen areas of the medial margins of the upper and lower pedicles of the vertebral arch. The treatment effectiveness was evaluated. Results: VAS and ODI scores were significantly improved at postoperative 3 days, 3 months, 6 months, and the last follow-up (P < 0.05). The area of the intervertebral foramen was 422.5 ± 159.2 mm2 preoperatively and 890.8 ± 367.7 mm2 postoperatively, the difference was statistically significant (P < 0.05). Conclusion: Percutaneous transforaminal approach multiple planar endoscopic decompression could achieve an accurate and effective decompression of the lumbar lateral spinal canal. This procedure has good short-term effects, and is especially suitable for elderly patients.

Activation of AKT signaling via small molecule natural compound prevents against osteoblast apoptosis and osteonecrosis of the femoral head.

Vinpocetine (Vinp), a natural compound extracted from the leaves of Phyllostachys pubescens with apoptosis modulatory properties in variety of disorders. In the present study, we investigated the possible mechanism of Vinp in alleviating of the progress of osteonecrosis of the femoral head (ONFH) both in vitro and in vivo experiments. The results showed that treatment with Vinp suppressed the dexamethasone (Dex) induced over-regulation of ROS level and apoptotic factors. Mechanistically, the Vinp activated Akt signaling pathway in osteoblast. Moreover, Vinp exerted a protective role in animal ONFH model. To summarize, this work illustrated Vinp possessed a new potential therapeutic drug in ONFH.

Effect of aberrantly methylated androgen receptor target gene PCDH7 on the development of androgen-independent prostate cancer cells.

BACKGROUND: Androgen-independent prostate cancer (AIPC) is an extremely malignant tumor developed from the androgen dependent (ADPC). However, the mechanism of transition process from ADPC to AIPC remains unknown. OBJECTIVE: Here we aimed to identify the androgen receptor (AR) target gene and its roles in AIPC. METHODS: Target genes of AR were identified by ChIP-seq in AIPC cells. AR target gene PCDH7 was detected by real time PCR and western blot. Methylation of PCDH7 was measured by bisulfite sequencing and bisulfite amplicon sequencing. Cell growth, invasion and apoptosis were measured by CCK-8, transwell and flow cytometry, respectively. RESULTS: AR was significantly enriched in the upstream of PCDH7 gene. The expression of PCDH7 was significantly decreased, while the methylation of PCDH7 was increased in the AIPC cells compared to the ADPC cells. DNA methyltransferase inhibitor significantly suppressed the methylation and increased the mRNA and protein level of PCDH7. Moreover, overexpression of DNMT1 remarkably reduced the mRNA and protein level of PCDH7. DNA methyltransferase inhibitor decreased the cell growth and invasion while promote the cell apoptosis in the AIPC cells. AR significantly target PCDH7, whose hypermethylation may repress cell growth and invasion, and promote apoptosis in AIPC. CONCLUSIONS: This study might provide a novel potential target for the treatment of AIPC.

Tophaceous gout causing lumbar stenosis: A case report.

RATIONALE: Gout in the spine is very rare. The clinical symptoms of the spinal gout are various and lack of specificity. The authors report a case of spinal gout causing lumbar stenosis. We never find such wide-invasive spinal gouty lesion in the published studies. PATIENT CONCERNS: A 68-year-old male had low back pain radiating to bilateral lower limbs, accompanying with intermittent claudication that lasted for 3 months and aggravated 5 days ago. DIAGNOSES: Spinal gout, lumbar stenosis. INTERVENTIONS: The patient underwent L2-L4 laminectomy, L2/3 L3/4 an d L4/5 discectomy and transforaminal lumbar interbody fusion with pedicle screw fixation. OUTCOMES: Dual-energy computed tomography detected extensive tophaceous deposits in L1/2 L2/3 L3/4 and L4/5 lumbar discs as well as the posterior column, especially L2-L3 and L4-L5 facet joints. During the surgery, we found a mass of chalky white material at the posterior column of L3 to L5 vertebral bodies, which also involved the intervertebral discs. Pathological examination confirmed the diagnosis of spinal gout. LESSONS: Although spinal gout is thought to be rare, the diagnosis should be considered if the patient had severe back pain and a history of gout. Dual-energy computed tomography is highly recommended for these patients.

Effects of hypoxia on differentiation of menstrual blood stromal stem cells towards tenogenic cells in a co-culture system with Achilles tendon cells.

Achilles tendons have a very poor capacity for intrinsic regeneration. The cell-based treatment strategy for Achilles tendinitis includes the application of mesenchymal stem cells (MSCs), which have high proliferative and multipotent differentiation ability, and is a promising approach. The aim of the present study was to explore the tenogenic potential of human menstrual blood stromal stem cells (MenSCs) in a co-culture system and to compare the tenogenic capability under normoxic and hypoxic conditions. MenSCs were co-cultured indirectly with Achilles tendon cells in a Transwell co-culture system for 1, 2, or 3 weeks in two different concentrations of oxygen (20 and 2% O2), whereas the control contained only MenSCs. The extracellular matrix of MenSCs in each system was evaluated by Alcian blue staining assay, histological staining, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and western blot analysis. Alcian blue staining assay revealed a significant increase (P<0.05) in proteoglycan secretion by the differentiated MenSCs. Identical results were obtained by RT-qPCR for collagen I, which was validated by western blot analysis. Considerably increased collagen I and collagen III gene expression levels were exhibited by cells in the co-culture treatment group when compared with the control (P<0.05); however, no significant difference was detected between the normoxic (20% O2) and hypoxic treatment (2% O2) groups. RT-qPCR was utilized to determine the expression levels of thrombospondin 4, scleraxis and tenascin C in the differentiated MenSCs; a significant increase in the expression of these specific genes was indicated in the co-culture treatment group compared with the control (P<0.05). Although the expression levels were markedly higher in hypoxia than in normoxia conditions, this difference was not significant. To conclude, the present study indicated that MenSCs manifested a strong proliferative and multipotent capacity for differentiation and differentiated into Achilles tenogenic cells. Therefore, the use of MenSCs may be considered in Achilles tendinitis therapy.

Differentiation Potential of Mesenchymal Stem Cells Derived from Adipose Tissue vs Bone Marrow Toward Annulus Fibrosus Cells In vitro.

BACKGROUND: Bone marrow stem cells (BMSCs) and adipose-derived stem cells (ADSCs) are two types of stem cells that commonly used in exogenous tissue engineering as well as endogenous tissue repair, however which type of cell is superior remains unknown. OBJECTIVE: This study was conducted to compare differentiation potential of BMSCs and ADSCs from Sprague-Dawley rats towards annulus fibrosus (AF)-like cells. METHOD: Stem cells and AF cells were cocultured with direct cell-to-cell contact in coculture plates with 0.4m pore size up till 21 days. AF markers expression at the histological level and molecular level were evaluated by histological analysis and dimethplmethplene blue (DMMB) assay as well as quantitative reverse-transcription polymerase chain reaction (qRT-PCR). RESULTS: qRT-PCR) results showed up regulation in AF marker gene expressions of both two MSCs after coculture. BMSCs demonstrated a statistically increased expression of collagen II and aggrecan from 7 days of coculture. However, these gene expressions in ADSCs showed a statistically increase at day 14 and day 21. And there was a statistically increase of Collagen I expression in BMSCs at 14 days and 21 days. But only after 21 days of coculture, ADSCs showed a statistically increase in collagen I expression. Moreover, histological analysis and dimethplmethplene blue (DMMB) assay mirrored the results of qRT-PCR. Morphologically, BMSCs became enlarged and triangular, while ADSCs were enlarged and rounded after coculture. CONCLUSION: These findings suggested that BMSCs might be superior as a cell source for annulus fibrosus repair compared to ADSCs.

[Progress on propionibacterium acnes and degenerative intervertebral disc].

The mechanism of degenerative intervertebral disc is very complex, which may be associated with multiple factors such as the mechanical stress force injury of intervertebral disc, nutritional deficiency, inflammatory stimulation, etc. Recently, many studies detected propionibacterium acnes(P. acnes) in degenerative intervertebral disc and supposed P. acnes was associated with degenerative intervertebral disc. Here, the papers related to P. acnes and degenerative intervertebral disc were reviewed. Further, we deduced the approach of P. acnes enterring into the intervertebral disc as well as the mechanism of P. acnes aggravating the disc degeneration. These may provide suggestions for treating degenerative intervertebral disc.

Minimally invasive plate osteosynthesis vs conventional fixation techniques for surgically treated humeral shaft fractures: a meta-analysis.

BACKGROUND: In this study, we performed a meta-analysis to identify whether minimally invasive plate osteosynthesis (MIPO) was superior to conventional fixation techniques (CFT) for treating humeral shaft fractures. METHODS: A systematic literature search was conducted up to February 2016 in ScienceDirect, Springer, MEDLINE, and PubMed databases for relevant papers that compared the outcomes of MIPO with CFT, such as open reduction with plate osteosynthesis (ORPO) and intramedullary nail (IMN) for treating humeral shaft fractures. Meta-analysis was performed with Review Manager 5.0 software. RESULTS: According to the search strategy, eight studies that covered 391 patients were enrolled, including four randomized controlled trials (RCTs), two prospective cohort trials, and two retrospective cohort trials. Our meta-analysis did not detect any significant difference between MIPO and CFT (IMN and ORPO) in terms of operative time, fracture union rate, and fracture union time. However, MIPO has a less rate of complications and iatrogenic radial nerve palsy than that of ORPO and higher adjacent joint function scores than those of IMN (p < 0.05). CONCLUSIONS: Based on the present evidence, this meta-analysis suggested that MIPO was a better choice for treating humeral shaft fractures than CFT. However, more high-quality randomized trials are still needed to further confirm this conclusion in the future.

Pooled analysis of non-union, re-operation, infection, and approach related complications after anterior odontoid screw fixation.

BACKGROUND: Anterior odontoid screw fixation (AOSF) has been one of the most popular treatments for odontoid fractures. However, the true efficacy of AOSF remains unclear. In this study, we aimed to provide the pooled rates of non-union, reoperation, infection, and approach related complications after AOSF for odontoid fractures. METHODS: We searched studies that discussed complications after AOSF for type II or type III odontoid fractures. A proportion meta-analysis was done and potential sources of heterogeneity were explored by meta-regression analysis. RESULTS: Of 972 references initially identified, 63 were eligible for inclusion. 54 studies provided data regarding non-union. The pooled non-union rate was 10% (95% CI: 7%-3%). 48 citations provided re-operation information with a pooled proportion of 5% (95% CI: 3%-7%). Infection was described in 20 studies with an overall rate of 0.2% (95% CI: 0%-1.2%). The main approach related complication is postoperative dysphagia with a pooled rate of 10% (95% CI: 4%-17%). Proportions for the other approach related complications such as postoperative hoarseness (1.2%, 95% CI: 0%-3.7%), esophageal/retropharyngeal injury (0%, 95% CI: 0%-1.1%), wound hematomas (0.2%, 95% CI: 0%-1.8%), and spinal cord injury (0%, 95% CI: 0%-0.2%) were very low. Significant heterogeneities were detected when we combined the rates of non-union, re-operation, and dysphagia. Multivariate meta-regression analysis showed that old age was significantly predictive of non-union. Subgroup comparisons showed significant higher non-union rates in age ≥ 70 than that in age ≤ 40 and in age 40 to <50. Meta-regression analysis did not reveal any examined variables influencing the re-operation rate. Meta-regression analysis showed age had a significant effect on the dysphagia rate. CONCLUSIONS/SIGNIFICANCES: This study summarized the rates of non-union, reoperation, infection, and approach related complications after AOSF for odontoid fractures. Elderly patients were more likely to experience non-union and dysphagia.

Differentiation of menstrual blood-derived stem cells toward nucleus pulposus-like cells in a coculture system with nucleus pulposus cells.

STUDY DESIGN: Human stromal stem cells derived from menstrual blood (MenSCs) and nucleus pulposus (NP) cells were cocultured under normal or low oxygen (O2) condition. OBJECTIVE: To assess the differentiation capability of MenSCs toward nucleus pulposus cells under normal or low oxygen condition. SUMMARY OF BACKGROUND DATA: Given the proliferative capacity and pluripotentiality of mesenchymal stem cells, mesenchymal stem cells transplantation is thought to be a promising approach to managing intervertebral disc degeneration. METHODS: Using coculture plates with 0.4-µm pore size polyethylene terephthalate track-etched inserts, MenSCs and NP cells (1:1 ratio) were cocultured with cell-to-cell contact for 2 weeks in normal (20% O2) or low oxygen tension (2% O2), respectively. Extracellular matrix accumulation was quantified by dimethylmethylene blue assay, histological staining, and quantitative reverse-transcription polymerase chain reaction. Novel characteristic human NP markers cytokeratin-19 (KRT19), carbonic anhydrase XII (CA12), and forkhead box F1 (FoxF1) were also detected by quantitative reverse-transcription polymerase chain reaction. RESULTS: The result of quantitative reverse-transcription polymerase chain reaction showed that aggrecan and COL2A1 genes expression was significantly increased in differentiated MenSCs (P < 0.05). There was significantly more COL2A1 gene expression in normoxic group than that in low O2 group (P < 0.05). But no significant difference was observed in aggrecan gene expression between normoxic group and low O2 group. These aforementioned results were also confirmed by histological analysis. We also found that the characteristic NP markers (KRT19, CA12, FoxF1) were significantly upregulated in differentiated MenSCs. Moreover, low O2 tension (2%) further enhanced these genes expression (P < 0.05). CONCLUSION: In our study, MenSCs were successfully differentiated into NP-like cells and may become a new source of seed cells for the treatment of intervertebral disc degeneration in the future. LEVEL OF EVIDENCE: N/A.

A systematic review and meta-analysis of unilateral versus bilateral pedicle screw fixation in transforaminal lumbar interbody fusion.

BACKGROUND: Transforaminal lumbar interbody fusion (TLIF) has become one of the most widely used procedures for lumbar spinal disorders. However, it is still unclear whether TLIF with unilateral pedicle screw (PS) fixation is as effective as that with bilateral PS fixation. We performed a meta-analysis of the literatures and aimed to gain a better understanding of whether TLIF with unilateral PS fixation was safe and effective for lumbar diseases. METHODOLOGY/PRINCIPAL FINDINGS: We systematically searched Ovid, Springer, and Medline databases for relevant randomized controlled trials (RCTs) that compared the clinical and radiological outcomes of unilateral versus bilateral PS fixation in TLIF. Risk of bias in included studies was assessed using the Cochrane Risk of Bias tool. We generated pooled risk ratios or weighted mean differences across studies. According to our predefined inclusion criteria, seven RCTs with a total of 441 patients were included in this study. Baseline characteristics were similar between the unilateral and bilateral groups. Our meta-analysis showed that no significant difference was detected between the two groups in terms of postoperative clinical function, fusion status, reoperation rate, complication rate, and hospital stay (p>0.05). Pooled estimates revealed that the unilateral group was associated with significantly reduced implant cost, operative time and blood loss (p<0.05). CONCLUSIONS/SIGNIFICANCES: Our meta-analysis suggested TLIF with unilateral PS fixation was as safe and effective as that with bilateral PS fixation for lumbar diseases in selected patients. Despite these findings, our meta-analysis was based on studies with small sample size and different study characteristics that might lead to the inconsistent results such as various functional outcomes among the included studies. Therefore, high-quality randomized controlled trials with larger sample size are also needed to further clarify these issues and to provide the long-term outcomes.

Lactate down-regulates matrix systhesis and promotes apoptosis and autophagy in rat nucleus pulposus cells.

The intervertebral disk (IVD) is avascular and anaerobic glycolysis has been recognized as the main source of energy. Due to anaerobic glycolysis, there are high levels of lactate production in disk. Previous study shows lactate concentration is elevated in the degenerated IVD. However, it is not clear how lactate causes degeneration of disks. In this study, we found that 2 mM lactate promote proliferation of NP cells, while 6 mM lactate slightly inhibit their proliferation. By detection under transmission electron microscopy, and western bolt for autophagy related protein beclin-1, LC3 and p62, we demonstrated that 6 mM lactate leads to autophagy induction of NP cells. TUNEL results showed that the apoptosis incidence was increased. High lactate concentration induced the degradation in protein expression and mRNA level of GAG content, type II collagen and slight increase of type I collagen. Based on these observations, we conclude that high lactate concentration is a pathogenic factor for IVD degeneration, and lactate metabolism may be a new therapeutic target for IVD degeneration.

Complications in degenerative lumbar disease treated with a dynamic interspinous spacer (Coflex).

PURPOSE: The purpose of this study was to quantify the intra- and postoperative complications of an interspinous process device (Coflex) in managing degenerative lumbar diseases and to investigate corresponding therapeutic strategies. METHODS: Between January 2008 and December 2012, we retrospectively analysed a total of 131 patients who underwent decompressive surgery along with the Coflex system for the treatment of degenerative lumbar diseases. The related complications were reported, and appropriate measures were taken. Clinical outcomes and radiological data were collected and analysed, and clinical outcomes were evaluated with paired-samples T test. RESULTS: Related complications occurred in 11 patients. Among them, six cases were found with surgical technique-related complications, including device-related complications in three cases: spinal process fracture (n = 1), Coflex loosening (n = 1), fixed-wing breakage (n = 1), dura mater tear in two cases and superficial wound infection in one case. All of them received corresponding conservative treatment and obtained a good result. The other five cases had non-device-related complications and required additional spinal surgery. The conservative therapy group had apparent improvement of VAS score and ODI, and remained well to final follow-up (P < 0.05). The second operation group also improved postoperatively (each P < 0.05). CONCLUSION: The Coflex dynamic interspinous process device shows a low complication and re-operation rate. Standard operation and strict follow-up observation can effectively avoid surgical technique-related complications. The key points to ensure surgical effect and to reduce non-device-related complications are mastering surgical indications and thorough intra-operative decompression.