Machine learning for the prediction of postoperative nosocomial pulmonary infection in patients with spinal cord injury.

PURPOSE: The purpose of this study was to establish the best prediction model for postoperative nosocomial pulmonary infection through machine learning (ML) and assist physicians to make accurate diagnosis and treatment decisions. METHODS: Patients with spinal cord injury (SCI) who admitted to a general hospital between July 2014 and April 2022 were included in this study. The data were segmented according to the ratio of seven to three, 70% were randomly selected to train the model, and the other 30% were used for testing. We used LASSO regression to screen the variables, and the selected variables were used in the construction of six different ML models. Shapley additive explanations and permutation importance were used to explain the output of the ML models. Finally, sensitivity, specificity, accuracy and area under receiver operating characteristic curve (AUC) were used as the evaluation index of the model. RESULTS: A total of 870 patients were enrolled in this study, of whom 98 (11.26%) developed pulmonary infection. Seven variables were used for ML model construction and multivariate logistic regression analysis. Among these variables, age, ASIA scale and tracheotomy were found to be the independent risk factors for postoperative nosocomial pulmonary infection in SCI patients. Meanwhile, the prediction model based on RF algorithm performed best in the training and test sets. (AUC = 0.721, accuracy = 0.664, sensitivity = 0.694, specificity = 0.656). CONCLUSION: Age, ASIA scale and tracheotomy were the independent risk factors of postoperative nosocomial pulmonary infection in SCI. The prediction model based on RF algorithm had the best performance.

Role of magnetic resonance imaging features in diagnosing and localization of disc rupture related to cervical spinal cord injury without radiographic abnormalities.

STUDY DESIGN: A retrospective study. OBJECTIVE: Traumatic cervical spinal cord injury (TSCI) is often associated with disc rupture. It was reported that high signal of disc and anterior longitudinal ligament (ALL) rupture on magnetic resonance imaging (MRI) were the typical signs of ruptured disc. However, for TSCI with no fracture or dislocation, there is still difficult to diagnose disc rupture. The purpose of this study was to investigate the diagnostic efficiency and localization method of different MRI features for cervical disc rupture in patient with TSCI but no any signs of fracture or dislocation. SETTING: Affiliated hospital of University in Nanchang, China. METHODS: Patients who had TSCI and underwent anterior cervical surgery between June 2016 and December 2021 in our hospital were included. All patients received X-ray, CT scan, and MRI examinations before surgery. MRI findings such as prevertebral hematoma, high-signal SCI, high-signal posterior ligamentous complex (PLC), were recorded. The correlation between preoperative MRI features and intraoperative findings was analyzed. Also, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of these MRI features in diagnosing the disc rupture were calculated. RESULTS: A total of 140 consecutive patients, 120 males and 20 females with an average age of 53 years were included in this study. Of these patients, 98 (134 cervical discs) were intraoperatively confirmed with cervical disc rupture, but 59.1% (58 patients) of them had no definite evidence of an injured disc on preoperative MRI (high-signal disc or ALL rupture signal). For these patients, the high-signal PLC on preoperative MRI had the highest diagnostic rate for disc rupture based on intraoperative findings, with a sensitivity of 97%, specificity of 72%, PPV of 84% and NPV of 93%. Combined high-signal SCI with high-signal PLC had higher specificity (97%) and PPV (98%), and a lower FPR (3%) and FNR (9%) for the diagnosis of disc rupture. And combination of three MRI features (prevertebral hematoma, high-signal SCI and PLC) had the highest accuracy in diagnosing traumatic disc rupture. For the localization of the ruptured disc, the level of the high-signal SCI had the highest consistency with the segment of the ruptured disc. CONCLUSION: MRI features, such as prevertebral hematoma, high-signal SCI and PLC, demonstrated high sensitivities for diagnosing cervical disc rupture. High-signal SCI on preoperative MRI could be used to locate the segment of ruptured disc.

Incidences and reasons of postoperative surgical site infection after lumbar spinal surgery: a large population study.

PURPOSE: The purpose of this study was to determine the incidences of postoperative acute surgical site infection (SSI) after lumbar spinal surgery and its possible reasons in our hospital during the past 9 years. METHODS: This is a retrospective study with a large sample size. The medical records of all included patients were reviewed, and patients with acute SSI were identified. The incidence and possible reasons of SSI were determined. RESULTS: A total of 7240 patients who underwent posterior lumbar spinal surgery were included in this study, and the total incidence of postoperative SSI was 1.53% (111/7240). Gram-negative bacteria were found to be dominant in postoperative wound infections after lumbar spinal surgery. And Escherichia coli were the most common pathogen in patients with SSI. The rate of postoperative SSI following lumbar spinal surgery was increased at first and then decreased during the past 9 years. Additionally, from 2011 to 2014, it was mainly deep infection in these patients, and then was mainly superficial infection from 2015 to 2019. Patients with lumbar spinal stenosis had the highest incidence of postoperative SSI (2.39%, P < 0.001). There was also a significant difference for the number of SSI cases among different surgeons. CONCLUSION: Based on a large population analysis, Gram-negative bacteria were the most common pathogen in postoperative SSI after lumbar spinal surgery. And patients with lumbar spinal stenosis had the highest incidence of SSI. Increasing the intervention of Gram-negative may be an important step to reduce the postoperative SSI after lumbar spinal surgery.

The effect of screw tunnels on the biomechanical stability of vertebral body after pedicle screws removal: a finite element analysis.

PURPOSE: Posterior reduction and pedicle screw fixation is a widely used procedure for thoracic and lumbar vertebrae fractures. Usually, the pedicle screws would be removed after the fracture healing and screw tunnels would be left. The aim of this study is to evaluate the effect of screw tunnels on the biomechanical stability of the lumbar vertebral body after pedicle screws removal by finite element analysis (FEA). METHODS: First, the CT values of the screw tunnels wall in the fractured vertebral bodies were measured in patients whose pedicle screws were removed, and they were then compared with the values of vertebral cortical bone. Second, an adult patient was included and the CT images of the lumbar spine were harvested. Three dimensional finite element models of the L1 vertebra with unilateral or bilateral screw tunnels were created based on the CT images. Different compressive loads were vertically acted on the models. The maximum loads which the models sustained and the distribution of the force in the different parts of the models were recorded and compared with each other. RESULTS: The CT values of the tunnels wall and vertebral cortical bone were 387.126±62.342 and 399.204±53.612, which were not statistically different (P=0.149). The models of three dimensional tetrahedral mesh finite element of normal lumbar 1 vertebra were established with good geometric similarity and realistic appearance. After given the compressive loads, the cortical bone was the first one to reach its ultimate stress. The maximum loads which the bilateral screw tunnels model, unilateral screw tunnel model, and normal vertebral model can sustain were 3.97 Mpa, 3.83 Mpa, and 3.78 Mpa, respectively. For the diameter of the screw tunnels, the model with a diameter of 6.5 mm could sustain the largest load. In addition, the stress distributing on the outside of the cortical bone gradually decreased as the thickness of the tunnel wall increased. CONCLUSIONS: Based on the FEA, pedicle screw tunnels would not decrease the biomechanical stability and strength of the vertebral body. A large diameter of screw tunnel and thick tunnel wall were helpful for the biomechanical stability of the vertebral body.

Incidence and risk factors for symptomatic spinal epidural haematoma following lumbar spinal surgery.

PURPOSE: Spinal epidural haematoma (SEH) is a common complication after lumbar spinal decompression surgery, and symptomatic SEH usually causes devastating neurological deficits. Although different risk factors for post-operative SEH have been reported, few studies focused on patients' laboratory tests. The purpose of this study was to analyze the incidence of symptomatic SEH following lumbar spinal surgery, as well as identify the risk factors for it. METHODS: Patients who underwent posterior lumbar spinal decompression surgery between January 2010 and August 2016 were included in this study and their medical records were retrospectively reviewed. Those who developed post-operative symptomatic SEH after the surgery were identified. The risk factors for SEH were analyzed by univariate and multivariate regression analysis. RESULTS: In total, 2715 patients were included in this study and 31 (1.14%) were identified with post-operative symptomatic SEH. Of these patients, 19 were males and 12 were females, with an average age of 59.39 ± 11.66 years. After multivariate logistic regression analysis, low serum calcium level (P = 0.025), blood type A (P = 0.04), increased estimated blood loss (P = 0.032), prolonged surgical duration (P = 0.018), and decreased post-operative globulin (P = 0.016) were identified as the independent risk factors for post-operative SEH following lumbar spinal surgery. Furthermore, prolonged surgical duration (odds ratio = 3.105) was the strongest risk factor for SEH. CONCLUSION: Based on a large population investigation, the incidence of symptomatic SEH following lumbar spinal decompression surgery was 1.14%. Blood type A, increased estimated blood loss, and prolonged surgical duration were identified as the independent risk factors for post-operative SEH while two new risk factors, including low serum calcium level and decreased post-operative globulin, were firstly identified in this study.

Demethylation-mediated miR-129-5p up-regulation inhibits malignant phenotype of osteogenic osteosarcoma by targeting Homo sapiens valosin-containing protein (VCP).

Previous studies demonstrated that increased Homo sapiens valosin-containing protein (VCP) may be involved in osteosarcoma (OS) metastasis. However, the underlying mechanism of VCP over-expression in OS remains unknown. In the present study, we found a significantly negative correlation between miR-129-5p and VCP protein expression in OS tissues with pulmonary metastasis (Spearman's rho, rs = -0.948). Bioinformatical prediction, Luciferase reporter assay, Western blot, and RT-PCR assays performed on OS cells indicated that VCP is a target of miR-129-5p. In addition, three CPG islands in the region of miR-129-5p promoter were detected by bioinformatical prediction, and significantly higher expression of miR-129-5p and lower methylation level of miR-129-2 gene in OS cells treated with 5-Aza-2'-deoxycytidine (a potent DNA demethylating agent) than in those untreated cells were observed. Furthermore, lower migratory and invasive ability was found in cells with elevated miR-129-5p than in those with decreased miR-129-5p. These findings indicated that increased miR-129-5p may be mediated by demethylation and inhibit OS cell migration and invasion by targeting VCP in OS, and targeting miR-129-5p/VCP signaling pathway may serve as a therapeutic strategy for OS management, although further studies will be necessary.

Prevalence of lumbar disc herniation in populations with different symptoms based on magnetic resonance imaging study.

BACKGROUND: Lumbar disc herniation (LDH) is common in aged human beings. This study is to investigate the prevalence of lumbar disc herniation (LDH) in different symptomatic populations attending outpatient clinics based on magnetic resonance imaging (MRI) studies, and to analyze the characteristics, distribution, and treatment strategies thereof. METHODS: Patients who visited our outpatient clinics between January 1, 2022, and December 31, 2022, with complaints of low back pain, either accompanied or unaccompanied by lower limb symptoms (radiating pain, numbness or muscle weakness), were included. All patients underwent comprehensive lumbar spine MRI examinations. The prevalence of LDH in different symptomatic populations, as well as the characteristics, distribution, and treatment strategies of disc herniation were analyzed. RESULTS: Among 8,161 individuals (3,411 males and 4,750 females), 4,496 were diagnosed with LDH, resulting in a prevalence of 55.1 %. Of these, 683 (15.2 %) individuals underwent surgical treatment. Among all patients, 3,529 exhibited only low back pain symptoms, 1,820 (51.6 %) were diagnosed with LDH, and 201 (11.0 %) received surgical treatment. Additionally, 2,673 patients with low back pain accompanied by lower limb symptoms were identified, with 1,608 individuals (82.1 %) diagnosed with LDH; 319 (19.8 %) underwent surgical treatment. Furthermore, 1,959 patients presented with lower limb symptoms only, 1,068 (54.5 %) were diagnosed with LDH, and 163 received surgical treatment (P < 0.001). The prevalence rate for males was 58.8 %, compared to females with 52.4 % (P < 0.01). The prevalence of LDH exhibited an initially increasing trend, later decreasing with advancing age. L4/5 and L5/S1 were the most commonly affected segments. CONCLUSION: LDH prevalence varies among patients with different symptoms, with a higher rate in those presenting with low back pain accompanied by lower limb symptoms. These symptomatic patients also exhibit a higher rate of surgical intervention.

The Effectiveness of Artificial Intelligence-based Pedicle Screw Trajectory Planning in Patients With Different Levels of Bone Mineral Density.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To evaluate the effectiveness of pedicle screw trajectory planning based on artificial intelligence (AI) software in patients with different levels of bone mineral density (BMD). SUMMARY OF BACKGROUND DATA: AI-based pedicle screw trajectory planning has potential to improve pullout force (POF) of screws. However, there is currently no literature investigating the efficacy of AI-based pedicle screw trajectory planning in patients with different levels of BMD. METHODS: The patients were divided into 5 groups (group A-E) according to their BMD. The AI software utilizes lumbar spine CT data to perform screw trajectory planning and simulate AO screw trajectories for bilateral L3-5 vertebral bodies. Both screw trajectories were subdivided into unicortical and bicortical modes. The AI software automatically calculating the POF and pullout risk of every screw trajectory. The POF and risk of screw pullout for AI-planned screw trajectories and AO standard trajectories were compared and analyzed. RESULTS: Forty-three patients were included. For the screw sizes, AI-planned screws were greater in diameter and length than those of AO screws (P<0.05). In groups B-E, the AI unicortical trajectories had a POF of over 200N higher than that of AO unicortical trajectories. POF was higher in all groups for the AI bicortical screw trajectories compared with the AO bicortical screw trajectories (P<0.05). AI unicortical trajectories in groups B-E had a lower risk of screw pullout compared with that of AO unicortical trajectories (P<0.05). CONCLUSIONS: AI unicortical screw trajectory planning for lumbar surgery in patients with BMD of 40-120 mg/cm3 can significantly improve screw POF and reduce the risk of screw pullout.

A Prediction Nomogram for Fractured Vertebra Recollapse After Posterior Reduction and Pedicle Screw Fixation in Thoracolumbar Fractures.

OBJECTIVE: This study aimed to establish a predictive nomogram model for recollapse of fractured vertebra after posterior pedicle screw fixation in thoracolumbar fractures (TLFs). METHODS: Patients undergoing posterior pedicle screw fixation for TLFs at our hospital between January 2016 and December 2021 were retrospectively reviewed. Patients were divided into 2 groups according to the presence or absence of recollapse of the fractured vertebra at the final follow-up. The predictors for fractured vertebra recollapse were identified by univariate and multivariable logistic regression analysis, and a nomogram model was developed. The prediction performance and internal validation were established. RESULTS: A total of 224 patients were included in this study. Of these, 46 (20.5%) patients developed recollapse of fractured vertebra. Age, thoracic and lumbar injury severity score, screw distribution in the fractured vertebra, and anterior vertebral height compression ratio were associated with vertebral recollapse. These predictors were used to construct a predictive nomogram. The area under the receiver operating characteristic curve of the nomogram model was 0.891. The concordance index was 0.891, and it was 0.877 with bootstrapping validation. The calibration curves and decision curve analysis also suggested that the nomogram model had excellent predictive performances for fractured vertebra recollapse. CONCLUSIONS: A clinical nomogram incorporating 4 variables was constructed to predict fractured vertebra recollapse after posterior pedicle screw fixation for TLFs. The nomogram demonstrated good calibration and discriminative abilities, which may help clinicians to make better treatment decisions.

Sparganosis of a thoracic vertebra misdiagnosed as bone metastasis from lung cancer.

Sparganosis is a rare parasitic infection caused by plerocercoid tapeworm larvae. We described a case of a 27-year-old man presenting with numbness in both legs and masses in the right lung and spine, initially thought to have spinal metastasis from lung cancer. However, after pathological and parasitological examinations, the patient was found to have spinal sparganosis, likely due to a history of consuming raw frogs. The patient was successfully treated with praziquantel, resulting in the recovery of muscle strength in his legs. This case highlights the importance of considering spinal sparganosis as a differential diagnosis in patients with spinal masses, especially those with a history of consuming raw or undercooked frogs. Accurate diagnosis and early treatment are crucial for managing this infection.

Trend of unplanned reoperation rates after lumbar degenerative surgery from 2011 to 2019: a large patient population study.

BACKGROUND: Unplanned reoperation is commonly performed due to postoperative complications. Previous studies have reported the incidence of unplanned reoperation following lumbar spinal surgery. But few study focused on the trend of reoperation rates, and the reasons of unplanned reoperation were not clear. In this study, we conducted a retrospective study to determine the trend of unplanned reoperation rates after degenerative lumbar spinal surgery from 2011 to 2019, and the reasons and risk factors of unplanned reoperation were also determined. METHODS: Data of patients who were diagnosed with degenerative lumbar spinal disease and underwent posterior lumbar spinal fusion surgery in our institution from January 2011 to December 2019 were reviewed. Those who received unplanned reoperation during the primary admission were identified. The demographics, diagnosis, surgical segments and postoperative complications of these patients were recorded. The rates of unplanned reoperation from 2011 to 2019 were calculated, and the reasons of unplanned reoperation were statistically analysed. RESULTS: A total of 5289 patients were reviewed. Of them, 1.91% (n = 101) received unplanned reoperation during the primary admission. The unplanned reoperation rates of degenerative lumbar spinal surgery firstly increased from 2011 to 2014, with a peak rate in 2014 (2.53%). Then, the rates decreased from 2014 to 2019, with the lowest one in 2019 (1.46%). Patients with lumbar spinal stenosis have a higher rate of unplanned reoperation (2.67%) compared with those diagnosed as lumbar disc herniation (1.50%) and lumbar spondylolisthesis (2.04%) (P < 0.05). The main reasons for unplanned reoperation were wound infection (42.57%), followed by wound hematoma (23.76%). Patients who underwent 2-segment spinal surgery had a higher unplanned reoperation rate (3.79%) than those receiving other segments surgery (P < 0.001). And different spine surgeons had different reoperation rates. CONCLUSIONS: The rates of unplanned reoperation after lumbar degenerative surgery increased at first and then decreased during past 9 years. Wound infection was the major reason for unplanned reoperation. 2-segment surgery and surgeon's surgical skills were related to the reoperation rate.

A practical dynamic nomogram model for predicting bone metastasis in patients with thyroid cancer.

Purpose: The aim of this study was to established a dynamic nomogram for assessing the risk of bone metastasis in patients with thyroid cancer (TC) and assist physicians to make accurate clinical decisions. Methods: The clinical data of patients with TC admitted to the First Affiliated hospital of Nanchang University from January 2006 to November 2016 were included in this study. Demographic and clinicopathological parameters of all patients at primary diagnosis were analyzed. Univariate and multivariate logistic regression analysis was applied to build a predictive model incorporating parameters. The discrimination, calibration, and clinical usefulness of the nomogram were evaluated using the C-index, ROC curve, calibration plot, and decision curve analysis. Internal validation was evaluated using the bootstrapping method. Results: A total of 565 patients were enrolled in this study, of whom 25 (4.21%) developed bone metastases. Based on logistic regression analysis, age (OR=1.040, P=0.019), hemoglobin (HB) (OR=0.947, P<0.001) and alkaline phosphatase (ALP) (OR=1.006, P=0.002) levels were used to construct the nomogram. The model exhibited good discrimination, with a C-index of 0.825 and good calibration. A C-index value of 0.815 was achieved on interval validation analysis. Decision curve analysis showed that the nomogram was clinically useful when intervention was decided at a bone metastases possibility threshold of 1%. Conclusions: This dynamic nomogram, with relatively good accuracy, incorporating age, HB, and ALP, could be conveniently used to facilitate the prediction of bone metastasis risk in patients with TC.

Development and biomechanical test of a new pedicle screw for thoracolumbar spinal surgery.

Rupture of the medial pedicle wall often occurs during pedicle screw insertion. This allows the pedicle screw to compress or cut the nerve root and/or spinal cord. In this paper, we designed a new double-threaded pedicle screw that has a cylindrical outer diameter and a conical core diameter, with a wide thread at the front, no thread in the middle, and a narrow thread at the rear, according to an analysis of the shortcomings of the conventional pedicle screw and anatomical parameters in 300 healthy adult volunteers. After the screw was placed, the non-threaded portion of the screw was located at the vertebral pedicle. No nerve root cutting occurred if the screw was misplaced and the medial wall of the vertebral pedicle was broken. We then performed biomechanical tests using a static universal testing machine and compared the new double-threaded screws with the conventional full-threaded pedicle screws, however, the differences were not obvious. In compression bending fatigue tests, the novel double-threaded pedicle screws were subjected to 5 million fatigue cycle loads without failure. The current study demonstrated that the new pedicle screw possesses similar biomechanical features as those of the conventional fully threaded pedicle screw. This provides a basis for further clinical applications.

Identification of a Novel Pyroptosis-Related Gene Signature Indicative of Disease Prognosis and Treatment Response in Skin Cutaneous Melanoma.

Purpose: Pyroptosis plays an important role in the occurrence and progression of many tumors; however, the specific mechanisms involved remain unknown. Here, we construct a pyroptosis-related gene signature that can be used to predict survival prognosis of skin cutaneous melanoma (SKCM) and provide guidance for clinical treatment. Methods: By integrating data from the two databases from the GTEx and TCGA, differentially expressed genes (DEGs) from normal tissues and skin cutaneous tumor tissues were identified. The main signaling pathways and function enrichment of these differential genes were determined. Univariate and multivariate COX regression analysis, and risk score analysis were used to construct a signature to assess its predictive value for overall survival. The mRNA expression of these five genes in melanoma cells was determined by quantitative polymerase chain reaction (qPCR). The pRRophetic algorithm was used to estimate the half-maximal inhibitory concentration (IC50) of chemotherapy drugs in SKCM patients. The expression of multiple immune checkpoint genes also was evaluated. Results: Sixteen DEGs associated with pyroptosis in SKCM and normal skin tissues were identified. Of these, 12 pyroptosis-related DEGs were associated with the prognosis of SKCM. A five-gene signature (GSDMA, GSDMC, IL-18, NLRP6, and AIM2) model was constructed. Patients were divided into high-risk and low-risk groups using the risk scores. Of these, the high-risk group had a worse survival prognosis. There are significant differences in the predicted sensitivity of the high-risk and low-risk groups to chemotherapeutic drugs. In addition, compared with the high-risk group, the low-risk group showed higher expression of PD-1, PDL-1, CTLA-4, LAG-3, and VSIR. Conclusion: In this study, we constructed a novel prognostic pyroptosis-related gene-signature for SKCM. These genes showed good predictive value for patient prognosis and could provide guidance for better treatment of SKCM patients.

Prediction of bone metastasis in non-small cell lung cancer based on machine learning.

Objective: The purpose of this paper was to develop a machine learning algorithm with good performance in predicting bone metastasis (BM) in non-small cell lung cancer (NSCLC) and establish a simple web predictor based on the algorithm. Methods: Patients who diagnosed with NSCLC between 2010 and 2018 in the Surveillance, Epidemiology and End Results (SEER) database were involved. To increase the extensibility of the research, data of patients who first diagnosed with NSCLC at the First Affiliated Hospital of Nanchang University between January 2007 and December 2016 were also included in this study. Independent risk factors for BM in NSCLC were screened by univariate and multivariate logistic regression. At this basis, we chose six commonly machine learning algorithms to build predictive models, including Logistic Regression (LR), Decision tree (DT), Random Forest (RF), Gradient Boosting Machine (GBM), Naive Bayes classifiers (NBC) and eXtreme gradient boosting (XGB). Then, the best model was identified to build the web-predictor for predicting BM of NSCLC patients. Finally, area under receiver operating characteristic curve (AUC), accuracy, sensitivity and specificity were used to evaluate the performance of these models. Results: A total of 50581 NSCLC patients were included in this study, and 5087(10.06%) of them developed BM. The sex, grade, laterality, histology, T stage, N stage, and chemotherapy were independent risk factors for NSCLC. Of these six models, the machine learning model built by the XGB algorithm performed best in both internal and external data setting validation, with AUC scores of 0.808 and 0.841, respectively. Then, the XGB algorithm was used to build a web predictor of BM from NSCLC. Conclusion: This study developed a web predictor based XGB algorithm for predicting the risk of BM in NSCLC patients, which may assist doctors for clinical decision making.

Short-segment fixation and transpedicular bone grafting for the treatment of thoracolumbar spine fracture.

Purpose: Thoracolumbar fracture is one of the most common fractures of spine. And short-segment posterior fixation including the fractured vertebra (SSPFI) is usually used for the surgical treatment of it. However, the outcomes of SSPFI for different types of thoracolumbar fractures are not clear, and whether it is necessary to perform transpedicular bone grafting is still controversial. This study was conducted to determine the clinical efficacy of SSPFI for the treatment of different types of single-level thoracolumbar fracture, and make clear what kind of fractures need transpedicular bone grafting during the surgery. Methods: Patients with single-level thoracolumbar fracture undergoing SSPFI surgery between January 2013 and June 2020 were included in this study. The operative duration, intraoperative blood loss, anterior vertebral height ratio (AVHR) and anterior vertebral height compressive ratio (AVHC) of the fractured vertebra, local kyphotic Cobb angle (LKA), vertebral wedge angle (VWA) and correction loss during follow up period were recorded. Outcomes between unilateral and bilateral pedicle screw fixation for fractured vertebra, between SSPFI with and without transpedicular bone grafting (TBG), and among different compressive degrees of fractured vertebrae were compared, respectively. Results: A total of 161 patients were included in this study. All the patients were followed up, and the mean follow-upped duration was 25.2 ± 3.1 months (6-52 months). At the final follow-up, the AVHR was greater, and the LKA and VWA were smaller in patients with bilateral fixation (6-screw fixation) than those with unilateral fixation (5-screw fixation) of AO type A3/A4 fractures (P < 0.001). The correction loss of AVHR, LKA and VWA in fractured vertebra were significantly great when preoperative AVHC was >50% (P < 0.05). For patients with AVHC >50%, the correction loss in patients with TBG were less than those without TBG at the final follow-up (P < 0.05). Conclusions: SSPFI using bilateral fixation was more effective than unilateral fixation in maintaining the fractured vertebral height for AO type A3/A4 fractures. For patients with AVHC >50%, the loss of correction was more obvious and it can be decreased by transpedicular bone grafting.

Transepithelial transport of Cerulenin across Caco-2 cell monolayers.

The transepithelial transport of Cerulenin across Caco-2 cell monolayers was examined in this study. The permeated amounts of Cerulenin were measured by HPLC method to calculate the permeation rate and the apparent permeability coefficient (P(app)). The transport of Cerulenin was independent on apical pH and exhibited concentration-dependent and nonsatuable even at 10 mM Cerulenin. The permeation rate at 1 mM Cerulenin in the apical-to-basolateral direction was 0.151 ng/min/mg of protein and the P(app) was 3.76 x 10(-6) cm/second. The permeation rate of Cerulenin was affected by neither metabolic inhibitors nor inhibitors for P-glycoprotein, as was the same case in monolayers treated with cytochalasin D. All these data from experiments indicated that transport of Cerulenin across Caco-2 cell monolayers was not mediated by ATP-dependent transport systems nor via paracellular pathway, but via passive diffusion without efflux by P-glycoprotein.

Valosin-containing protein promotes metastasis of osteosarcoma through autophagy induction and anoikis inhibition via the ERK/NF-κß/beclin-1 signaling pathway.

Valosin-containing protein (VCP) promotes the development of metastasis in osteosarcoma (OS) via the PI3K/Akt signaling pathway. However, inhibition of the PI3K/Akt pathway does not completely reverse VCP-mediated invasion and migration of OS, suggesting that VCP-mediated OS invasion and migration involves additional mechanisms. In the present study, a positive correlation between the expression of VCP and cell autophagy was observed among OS tissues. Inhibiting VCP may decrease the survival of malignant cells; however, an autophagy stimulator may compensate for VCP inhibition and promote malignant cell survival. Altering the level of autophagy did not affect cell invasiveness or migration. ERK, NF-κß and beclin-1 protein expression levels were markedly decreased following VCP inhibition. These findings indicated that VCP may induce autophagy and enhance anoikis resistance without affecting cell invasiveness or migration. Via anoikis resistance, VCP may promote metastasis in OS. Therefore, targeting of the ERK/NF-κß/beclin-1 signaling pathway may be an effective therapeutic strategy for the management of OS.

Are Routine Postoperative Laboratory Tests Really Necessary After Lumbar Spinal Surgery?

BACKGROUND: For patients undergoing lumbar spinal surgery, many surgeons routinely perform laboratory tests within 3 days after surgery. However, few studies have reported the necessity for routine laboratory tests for patients with uncomplicated cases within 3 days after surgery. METHODS: We performed a retrospective study of patients with lumbar degenerative disease who had undergone lumbar spinal surgery from May 2014 to May 2017. The perioperative patient information was recorded. The abnormal postoperative laboratory tests were recorded. Finally, the incidence and risk factors for patients requiring postoperative clinical treatment were analyzed. RESULTS: A total of 1915 patients were included in the present study. Postoperative laboratory tests had been ordered for 870 patients (45.43%). Of these patients, only a small proportion had required postoperative clinical intervention to treat abnormal serum hemoglobin (2.53%), albumin (1.95%), serum potassium (0.92%), or serum calcium (6.55%) levels. Multivariate logistic regression analysis showed that female gender and operative time were risk factors for the need for blood transfusion after lumbar spinal surgery. Age and operative time were risk factors for patients requiring albumin supplementation after lumbar spinal surgery. Finally, intraoperative blood loss and operative time were independent risk factors for patients requiring calcium supplementation after surgery. CONCLUSIONS: Owing to the small number of postoperative clinical interventions for abnormal laboratory test results, we believe that the use of routine laboratory tests within 3 days after lumbar spinal surgery for patients with uncomplicated cases are unnecessary. Our results showed that operative time is a potential risk factor for the necessity for clinical treatment after lumbar spinal surgery.

The risk factors for bone metastases in patients with colorectal cancer.

This retrospective analysis aim to evaluate the potential risk factors for bone metastases (BM) in patients who were diagnosed with colorectal cancer (CRC).A total of 2790 patients diagnosed with CRC between January 2006 and December 2016 were collected in this study. All patients were divided into 2 groups, BM and no BM. The associations between biomarkers (including age, gender, histopathological types, alkaline phosphatase (ALP), carcinoembryonic antigen (CEA), cancer antigen 125, and so on), and BM in patients with CRC were analyzed. All the analyses were conducted by SPSS software (version 22.0, SPSS, Chicago, IL).Of all patients, 74 (2.7%) were identified with BM. The level of serum ALP, CEA, and cancer antigen 125 in patients with BM were obviously higher than those without BM (P < .001, P = .005, and P < .001). And the cut-off values of ALP, CEA, and cancer antigen 125 were 85.5 U/L, 6.9 mmol/L, and 16.8 mmol/L, respectively.ALP, CEA, and cancer antigen 125 were identified as the independent risk factors for BM in patients with CRC.