Parvalbumin interneurons belong to the major types of GABAergic interneurons. Although the distribution and pathological alterations of parvalbumin interneuron somata have been widely studied, the distribution and vulnerability of the neurites and fibers extending from parvalbumin interneurons have not been detailly interrogated. Through the Cre recombinase-reporter system, we visualized parvalbumin-positive fibers and thoroughly investigated their spatial distribution in the mouse brain. We found that parvalbumin fibers are widely distributed in the brain with specific morphological characteristics in different regions, among which the cortex and thalamus exhibited the most intense parvalbumin signals. In regions such as the striatum and optic tract, even long-range thick parvalbumin projections were detected. Furthermore, in mouse models of temporal lobe epilepsy and Parkinson's disease, parvalbumin fibers suffered both massive and subtle morphological alterations. Our study provides an overview of parvalbumin fibers in the brain and emphasizes the potential pathological implications of parvalbumin fiber alterations.
Mice ; Animals ; Epilepsy, Temporal Lobe/pathology* ; Parvalbumins/metabolism* ; Parkinson Disease/pathology* ; Neurons/metabolism* ; Interneurons/physiology* ; Disease Models, Animal ; Brain/pathology*

Objective:To compare the efficacy of forceful reduction percutaneous pedicle screw and ordinary percutaneous pedicle screw in the treatment of osteoporotic thoracolumbar burst fracture with kyphosis.Methods:A retrospective cohort study was conducted to analyze the clinical data of 566 patients with osteoporotic thoracolumbar burst fracture with kyphosis admitted to Honghui Hospital, Xi ′an Jiaotong University from January 2015 to December 2018, including 191 males and 375 females, with age range of 48-79 years [(61.7±10.7)years]. Fracture segments were located at T 11 in 134 patients, T 12 in 154, L 1 in 160, and L 2 in 118. All fractures were type IIIA according to the acute symptomatic osteoporotic thoracolumbar fracture classification (ASOTLF). The thoracolumbar osteoporotic fracture severity score assessment system (TLOFSAS) score was ≥5 points. A total of 275 patients underwent forceful reduction and percutaneous pedicle screw internal fixation (forceful reduction screw group), and 291 patients underwent common percutaneous pedicle screw internal fixation (common screw group). The operation time, intraoperative blood loss, times of X-ray exposure on patients and measures documented before operation, at 3 days after operation and at 2 years after operation including anterior height ratio of the injured vertebrae, sagittal Cobb angle of the injured vertebrae, Japanese Orthopaedic Association (JOA) score and visual analog scale (VAS) were compared between the two groups. Moreover, degree of correction of Cobb angle at 3 days after operation, loss of correction of Cobb angle at 2 years after operation and postoperative complications were observed. Results:All patients were followed up for 25-34 months [(29.9±3.4)months]. The operation time, intraoperative blood loss and times of X-ray exposure on patients in forceful reduction screw group were (69.4±10.2)minutes, (60.3±13.1)ml and (26.8±3.7)times, less than (80.6±11.9)minutes, (80.7±15.4)ml and (30.4±3.4)times in common screw group (all P<0.01). There was no significant difference in anterior height ratio of the injured vertebrae between the two groups before operation and at 3 days after operation (all P>0.05). The anterior height ratio of the injured vertebrae in forceful reduction screw group was (95.5±2.3)% at 2 years after operation, significantly higher than (85.4±1.7)% in common screw group ( P<0.01). There was no significant difference in sagittal Cobb angle of the injured vertebrae between the two groups before operation ( P>0.05). The sagittal Cobb of the injured vertebrae in forceful reduction screw group at 3 days and 2 years after operation were (7.9±1.6)° and (8.8±1.5)°, lower than (10.6±1.1)° and (12.3±1.2)° in common screw group ( P<0.05 or 0.01). There were no significant difference in JOA score and VAS between the two groups before operation, at 3 days and at 2 years after operation (all P>0.05). The degree of correction of Cobb angle in forceful reduction screw group was (19.4±2.5)°, higher than (17.3±2.6)° in common screw group ( P<0.05). The loss of correction of Cobb angle in forceful reduction group was less than that in common screw group at 2 years after operation, but the difference was not statistically significant ( P>0.05). The incidence of postoperative complications in forceful reduction screw group was 12.4% (34/275), compared to 14.1% (41/291) in common screw group ( P>0.05). There were no complications such as iatrogenic nerve injury, fracture or loosening of internal fixator or leakage of bone cement in the spinal canal in both groups. Conclusions:For osteoporotic thoracolumbar burst fracture with kyphosis, forceful reduction and percutaneous pedicle screw internal fixation can significantly shorten operation time, reduce intraoperative blood loss and times of X-ray exposure on patients, restore height of the injured vertebrae, correct kyphosis and maintain reduction height of the injured vertebrae in contrast with conventional percutaneous pedicle screw internal fixation.

Objective:To investigate the efficacy of flexion-lateral curvature-supination reduction combined with primary anterior surgery for the treatment of lower cervical dislocation with unilateral facet inter-locking.Methods:A retrospective analysis was performed in the 32 patients who had been admitted to Department of Spine Surgery, Honghui Hospital for lower cervical dislocation with unilateral facet interlocking from November 2015 to October 2018. According to their treatments, they were divided into 2 groups. In the emergency group treated by flexion-lateral curvature-supination reduction combined with primary anterior surgery, there were 13 males and 3 females, aged from 24 to 63 years. In the traction group treated by cranial traction reduction combined with secondary anterior surgery, there were 12 males and 4 females, aged from 20 to 64 years. The operation time, intraoperative blood loss, hospital stay, bone graft fusion, American Spinal Injury Association (ASIA) grade and Japanese Orthopaedic Association (JOA) score were compared between the 2 groups.Results:There was no significant difference in the preoperative general data between the 2 groups, showing they were comparable ( P<0.05). All patients were followed up from 26 to 40 months. The hospital stay for the emergency group [(7.2±1.2) d] was significantly shorter than that for the traction group[(10.9±1.2) d] ( P<0.05). There was no significant difference in the operation time, blood loss, ASIA grade or JOA score between the 2 groups ( P>0.05). All patients achieved osseous fusion of intervertebral space. Conclusion:Compared with traditional methods, flexion-lateral curvature-supination reduction combined with primay anterior surgery shows no significant difference in the recovery of neurological function but leads to a shorter hospital stay.

Objective:To establish the acute symptomatic osteoporotic thoracolumbar fracture (ASOTLF) classification system, and to examine the reliability and evaluate the effect of clinical application.Methods:A retrospective case series study was conducted to analyze the clinical data of 1 293 patients with osteoporotic thoracolumbar fracture(OTLF) admitted to Honghui Hospital from January 2016 to December 2018. There were 514 males and 779 females, aged 57-90 years [(71.4±6.3)years]. The T value of bone mass density was -5.0--2.5 SD [(-3.1±-0.4)SD]. According to the clinical symptoms a and fracture morphology, OTLF was divided into 4 types, namely type I(I occult fracture), type II(compressed fracture), type III (burst fracture) and type IV(unstable fracture). The type II was subdivided into three subtypes (type IIA, IIB, IIC), and the Type III into two subtypes (type IIIA, IIIB). of all patients, 75 patients (5.8%) were with type I, 500 (38.7%) with type II A, 134 (10.4%) with type IIB, 97 (7.5%) with type IIC, 442 (34.2%) with type IIIA, 27(2.1%) with type IIIB and 18 (1.4%) with type IV. After testing the validity of the classification, different treatment methods were utilized according to the classification, including percutaneous vertebroplasty (PVP) for Type I, PVP after postural reduction for Type II, percutaneous kyphoplasty (PKP) for Type IIIA, posterior reduction and decompression, bone graft fusion and bone cement-augmented screw fixation for Type IIIB, and posterior reduction, bone graft fusion and bone cement-augmented screw fixation for Type IV. The visual analog score (VAS), Oswestry disability index (ODI), Frankel grade of spinal cord injury, local Cobb Angle, and vertebral body angle (vertebral body angle) were recorded in all patients and in each type of patients before surgery, at 1 month after surgery and at the last follow-up. The neurological function recovery and complications were also recorded.Results:The patients were followed up for 24-43 months [(29.9±5.1)months]. A total of 3 000 assessments in two rounds were conducted by three observers. The overall κ value of inter-observer credibility was 0.83, and the overall κ value of intra-observer credibility was 0.88. The VAS and ODI of all patients were (5.8±0.7)points and 72.5±6.6 before surgery, (1.8±0.6)points and 25.0±6.3 at 1 month after surgery, and (1.5±0.6)points and 19.5±6.2 at the last follow-up, respectively (all P<0.05). The Cobb angle and vertebral body angle of all patients were (13.0±9.1)° and (8.0±4.6)° before surgery, (7.9±5.2)° and (4.6±2.9)° at 1 month after surgery, and (9.1±6.0)° and (5.8±3.0)° at the last follow-up, respectively (all P<0.05). At the last follow-up, VAS, ODI, Cobb Angle and VBA of each type of patients were significantly improved compared with those before surgery (all P<0.05). The spinal cord compression symptoms were found 1 patient with type IV and 5 patients with type IIIB preoperatively. At the last follow-up, neurological function improved from grade C to grade E in 1 patient and from grade D to grade E in 5 patients ( P<0.05). The lower limb radiation pain or numbness in 3 patients with type IV and 22 patients with type III preoperatively were fully recovered after surgical treatment at the last follow-up except for three patients. Conclusions:The ASOTLF classification is established and has high consistency and reliability. The classification-oriented treatment strategy has achieved a relatively satisfactory effect, indicating that the classification has a certain guiding significance for treatment of OTLF.

Objective:To propose a new grading system-the posterior ligament-bone injury classification and severity (PLICS) score for subaxial cervical spine injury, and evaluate its value in guiding the approach selection for subaxial cervical fracture and dislocation.Methods:All of 394 cases of subaxial cervical fracture and dislocation who received single anterior reduction and fixation in our hospital from January 2002 to December 2015 were retrospectively analyzed. According to the inclusion and exclusion criteria, 354 cases were finally included in this study. The Patients experienced internal fixation failure, postoperative kyphosis or interspinal process space dilation during follow-up were included into the failure group. Other patients were included into the successful group. The difference of visual analogue scale (VAS), neck disability index (NDI), ASIA score and PLICS score before and after surgery between the two groups was compared respectively. The PLICS score is composed of left, right and posterior columns. The injury of the posterior column was classified into mild, moderate and severe degrees, with 1-3 points respectively. The evaluation of lateral column injury included ligament and bone structure. The evaluation of ligament injury included: 1 point for the subluxation of the facet joint, 2 points for the dislocation or the facet joint; Fractures of the lateral column was classified into mild, moderate and severe degrees, with 1-3 points respectively. For the evaluation of the lateral column, the highest score of ligament or bone structure injury was reflected as the score of posterior column injury and was taken into the calculation of the final PLICS score.Results:All 354 patients had complete follow-up data, and the average follow-up time was 18.0±4.0 months, including 339 patients of successful group and 15 patients of failure group. At the 12 month follow-up, the average VAS score of the patients in the successful group decreased from 6.9±0.6 before the operation to 1.9±0.6 ( t=22.481, P<0.0001), and the average VAS score of the patients in the failure group decreased from 5.6±1.0 to 1.1±0.3 ( t=77.252, P<0.0001). The difference between the two groups was statistically significant. The NDI score of the successful group was significantly lower than that of the failure group (7.1%±1.2% vs 15.7%±2.7%, t=24.993, P<0.0001). PLICS score in two groups of patients were analyzed. There was a significant difference in PLICS scores between the two groups ( t=8.777, P<0.0001). According to the PLICS score, the ROC operating curve of the failure of internal fixation after anterior-only surgery was determined. The area under the curve was 0.981, and the 95% confidence interval was 0.943, 1.000. When the PLICS score was 6.5, the maximum value of the Jordan index was 0.927, the sensitivity was 0.994, and the specificity was 0.067. Considering the clinical practicality of PLICS score and the different clinical outcomes of the sub-classification groups of the PLICS score=7, we finally set the threshold as PLICS score=7 with the unilateral severe lateral mass fracture. Conclusion:The PLICS score is based on the anatomy of the posterior three-column structure of the subaxial cervical spine. It gives consideration to the bony structures, including bilateral lateral mass, spinous process, lamina, and the ligament structures. What's more, the overall damage severity of the posterior three columns of the subaxial cervical spine was quantified according to the evaluation of the injury characteristics of each column of ligament-bone structure. In this study, PLICS score and clinical efficacy were compared between two groups of patients, and it was finally determined that when PLICS score ≥7 with the unilateral severe lateral mass fracture, the risk of internal fixation failure is higher for anterior-only approach surgery alone. For these patients, anterior and posterior approach surgery may be considered.

Objective: To analyze the differentially expressed microRNA (miRNA) and their target genes in peripheral blood and bone tissue of postmenopausal osteoporosis (PMOP), and provide basis for the study of pathogenesis as well as biomarkers identification of PMOP. Methods: Two miRNA datasets of PMOP from the public platform NCBI-GEO DataSets were obtained, including GSE64433 (the miRNA expression profile of peripheral blood samples, including 23 PMOP patients and 25 controls) and GSE74209 (the miRNA expression profile of the femoral neck bone tissue sample, including six PMOP patients and six controls). R/Bioconductor was performed for data analysis and differentially expressed miRNA screening, and miRNAs with fold change>2 & P<0.05 between osteoporosis and controls were selected as differentially expressed miRNA. The miRNA target gene prediction was performed by combining TargetScan, miRDB and miRTarBase databases. The miRNA-target gene regulatory network was constructed and analyzed by Cytoscape. Results: There were 224 differentially expressed miRNAs (75 up-regulated miRNAs and 149 down-regulated miRNAs) in the peripheral blood samples of PMOP group (GSE64433 dataset) and 132 differentially expressed miRNAs (58 up-regulated miRNAs and 74 down-regulated miRNAs) in the femoral neck bone tissue of PMOP group (GSE74209 dataset). We combined the results from the two datasets and obtained 8 miRNAs down-regulated in both datasets, and the 8 miRNAs regulated a total of 327 target genes, and 10 of these target genes were co-regulated by two miRNAs. Conclusions The core miRNAs and the target genes regulated by multiple miRNAs in the regulatory network may play important roles in the pathogenesis of PMOP and have potential application values as molecular biomarkers of disease. These findings are meaningful for the studies of PMOP pathogenesis, biomarkers screening and prevention of osteoporotic fractures.

Objective: To explore the safety and effectiveness of a novel percutaneous self-expanding forceful reduction screw system in the treatment of thoracolumbar fracture with severe vertebral height loss. Methods: Thirty-eight patients of thoracolumbar fracture with more than 50%vertebral height loss were treated with the novel percutaneous self-expanding forceful reduction screw between March 2014 and June 2015. The screw system is a single plane screw with a reduction angle of 0,3,6,9 degrees. During the operation, the fracture vertebral body was automatically restored during the locking process of the top cap. All the patients were single vertebral fractures. Percutaneous screw fixation and reduction was used in the operation. Two groups of screws were used to fix the two adjacent vertebrae of the injured vertebra and to restore the injured vertebral body, without fusion treatment. The vertebral body index (VBI), height of the anterior margin of fractured vertebra (HAMFV), vertebral body angle (VBA), bisegmental Cobb angle (BCA), visual analog scale (VAS) and Oswestry disability index (ODI) of the patients before and after operation, 6 months after operation, and at the end of the follow-up were compared. The scoring results were compared using a t test. Results: The operation was completed successfully in 38 cases. A total of 152 screws were placed. The accuracy rate of CT evaluation was 98.7%. The average operation time was 90.7±21.9 min, and the average intraoperative bleeding amount was 89.2±31.9 ml. The patients' preoperative VBI, HAMFV, VBA, BCA, VAS and ODI scores were 0.38±0.07, 0.38±0.06, 25.45°±4.54°, 18.66°±8.57°, 7.76±1.02, and 44.58%±2.33%, respectively. The postoperative measurements were 0.93±0.03, 0.95±0.02, 3.71°± 1.35°, 5.84°±6.80 °, 4.29±1.16 and 24.37%±1.88%. At the last follow-up, the measurements were 0.92±0.03, 0.94±0.02, 3.89° ±1.31°,6.05°±7.00°, 1.71±0.65 and 5.95%±2.67%. There was significant difference between the preoperative and postoperative data, as well as the preoperative and the last follow-up data (P<0.05). Conclusion In the treatment of thoracolumbar fractures with severe loss of vertebral height, the novel percutaneous self-expanding forceful reduction screw system has achieved satisfactory vertebral height restoration and kyphosis correction.

Objective To investigate the effect of intravenous tranexamic acid (TXA) on perioperative hidden blood loss in percutaneous pedicle screw fixation for thoracolumbar fractures.Methods A prospective study was conducted in the 113 patients who would be subjected to percutaneous pedicle screw fixation for thoracolumbar fracture from January 2017 to December 2017.They were randomly assigned into an observation group (n =58) receiving intravenous drip of 15 mg/kg TXA 30 minutes preoperation or a control group (n =55) receiving intravenous drip of normal saline solution 30 minutes preoperation.The total blood loss and hidden blood loss 24 hours postoperation,D-dimer volume,incidences of deep vein thrombosis and other complications were recorded and compared between the 2 groups.Results There were 54 patients in the observation group and 50 patients in the control group for statistic analysis.The observation group had significantly less total blood loss (319.0 ± 140.5 mL) and hidden blood loss (242.0 ± 143.4 mL) 24 hours postoperation than the control group (418.7 ± 188.1 mL and 354.7 ± 181.9 mL,respectively) (P ＜ 0.05).There were no significant differences between the 2 groups in operation time or intraoperative blood loss (P ＞ 0.05).The volume of postoperative D-dimer was significantly higher than the preoperative value in both groups (P ＜ 0.05).No thromboembolic events occurred in either group.Conclusion Intravenous TXA may significantly reduce intraoperative hidden blood loss with no increased rik of thromboembolic events in percutaneous pedicle screw fixation for thoracolumbar fractures.

Objective To compare minimally invasive percutaneous pedicle screw fixation and open pedicle screw fixation for neurologically intact thoracolumbar fractures.Methods A retrospective study was conducted in the 180 patients who had been treated for thoracolumbar fractures without neurological deficits from January 2016 to December 2016.Of them,93 were treated by minimally invasive percutaneous pedicle screw fixation and 87 by open pedicle screw fixation.The 2 groups were compared in terms of blood loss,radiological parameters,visual analogue scale (VAS) and Oswestry disability index (ODI).Results Compared with the open surgery group,the minimally invasive surgery group had significantly shorter operating time (95.8 ±33.4 min versus 106.3 ±30.9 min),significantly less intraoperative blood loss (65.8 ±40.3 mL versus 183.1 ± 77.5 mL),significantly less total blood loss in theory 24 hours after surgery (374.7 ± 160.6 mL versus 614.8 ± 242.6 mL) and significantly shorter hospital stay (5.2 ± 2.0 d versus 6.7 ± 2.7 d),but significantly longer C-arm exposure time (23.6 ±4.2 min versus 12.4 ±4.1 min) and significantly more hidden blood loss 24 hours after surgery (308.9 ± 159.0 mL versus 243.5 ± 195.5 mL) (P ＜ 0.05).Compared with preoperation,significant improvements were observed at one week postoperation and the last follow-up in the 2 groups regarding the percentage of anterior height of the fractured vertebral body and cobb angle (P ＜ 0.05),but there were no significant differences in the percentage of anterior height of the fractured vertebral body or cobb angle between the 2 groups at one week postoperation or at the last follow-up (P ＞ 0.05).At 3 days postoperation,significant better pain relief was observed in the minimally invasive surgery group than in the open surgery group (P ＜ 0.01),but at the last follow-up no obvious pain was reported in either group.At the last follow-up,there was no significant difference between the 2 groups in ODI (6.2 ± 1.1 versus 6.0 ± 1.4) (P =0.320).Conclusions In the treatment of neurologically intact thoracolumbar fractures,minimally invasive percutaneous pedicle screw fixation may lead to shorter operating time,less blood loss and shorter hospital stay but no poorer radiological outcomes or long-term patient-reported outcomes than the open pedicle screw fixation.However,it should be noted that the former may lead to a higher volume of hidden blood loss.