Objective To explore and evaluate the accuracy and feasibil ity of individual rapid prototype (RP) drill templates for atlantoaxial pedicle screw implantation. Methods Volumetric CT scanning was performed in 8 adult cadaveric atlas and axis to collect Dicom format datas. Then three-dimensional (3D) images of atlas and axis were reconstructed and the parameters of pedicles of 3D model were measured by using software Mimics 10.01. The 3D model was saved by STLformat in Mimics. The scattered point cloud data of 3D model were processed and the 3D coordinate system was located in software Imageware 12.1. The curves and surfaces of 3D model were processed in software Geomagic Studio 10. The optimal trajectory of pedicle screw was designed and a template was constructed which accorded with the anatomical morphology of posterior arch of atlas and lamina of axis by using software Pro/Engineer 4.0. The optimal trajectory of pedicle screw and the template were integrated into a drill template finally. The drill template and physical models of atlas and axis were manufactured by RP (3D print technology). The accuracy of pilot holes of drill templates was assessed by visually inspecting and CT scanning. Results The individual drill template was used conveniently and each template could closely fit the anatomical morphology of posterior arch of atlas and lamina of axis. Template loosening and shifting were not found in the process of screw implantation. Thirty-two pedicle screws were inserted. Imaging and visual inspection revealed that the majority of trajectories did not penetrate the pedicle cortex, only 1 cortical penetration was judged as noncritical and did not injury the adjacent spinal cord, nerve roots, and vertebral arteries. The accuracy of atlas pedicle screw was grade 0 in 15 screws and grade I in 1 screw, and the accuracy of axis pedicle screw was grade 0 in 16 screws. Conclusion The potential of individual drill templates to aid implantation of atlantoaxial pedicle screw is promising because of its high accuracy.
Objective To investigate the classification of atlas pedicles and the methods of the pedicle screw fixation. Methods To study the classification of atlas pedicles, 48 dry adult atlas specimens were measured. By atlas 3D-CT reconstruction, two transverse sections were establ ished by going through the one third of the lateral atlas pedicle and 2 mmbelow the vertebral artery sulcus. By setting 3.50 mm and 1.75 mm as the standardized diameter and radius for the screwand according to the thickness of bone substance of vertebral artery sulcus that went through the one third of the lateralatlas pedicle, the anatomical morphology of atlas pedicles were classified into three types: general type with 40 specimens (83%), l ight variation type with 6 specimens (13%), and severe variation type with 2 specimens (4%). The entry pathway was confirmed by the intersection l ine of the two transverse sections that went through the lateral one third of the atlas pedicle and 2 mm below the vertebral artery sulcus. The project-point of the entry pathway on the atlas posterior arch was considered to be the entry point. Forty-eight dry atlas specimens were used to measure the following relevant anatomic data with an electronic cal iper: the distance between the entry point and the posterior margin of the lateral mass (L1), the height of atlas pedicle at the entry point (L2), the vertical distance between the entry point and the inferior articular facet of the lateral mass (L3), the mass height at the entry point (L4), the mass width at the entry point (L5), the width of the atlas pedicle at the entry point (L6), the thickness of the pedicle under the vertebral artery sulcus at the entry pathway (H1). To research the method of the pedicle screw fixation, 12 fresh-frozen adult atlas specimens were adopted to simulate the fixation of the pedicle screw. The thickness of the bone substance of vertebral artery sulcus on both the left and the right sides of the pathway was grinded into 3 types: 1.5 mm and 2.5 mm, 1.5 mm and 4.0 mm, 2.5 mm and 4.0 mm, and each type had four specimens. The entry pathway was confirmed by the intersection l ine of two transverse sections that went through the lateral one third of atlas pedicle and 2 mm below the vertebral artery sulcus. Results On the left side, L1 was (5.79 ± 1.24) mm, L2 (4.55 ± 1.29) mm, L3 (5.12 ± 1.06) mm, L4 (12.43 ± 1.01) mm, L5 (12.66 ± 1.37) mm, L6 (7.86 ± 0.77) mm, and H1 (4.11 ± 1.25) mm. On the right side, L1 was (5.81 ± 1.26) mm, L2 (4.49 ± 1.22) mm, L3 (5.15 ± 1.05) mm, L4 (12.49 ± 0.98) mm, L5 (12.65 ± 1.38) mm, L6 (7.84 ± 0.78) mm, and H1 (4.13 ± 1.29) mm. There was no significant difference between the two sides (P gt; 0.05). After simulation of inserting screws, no screw in the specimens was found to break the bone substance in the sulcus of vertebral artery. Conclusion For the pedicle screw fixation of those patients whose atlas posterior arches are not high enough, we might partly drill through or beyond the atlas posterior arch. The entry point should be ascertained by preoperative 3D-CT reconstruction and intra-operative exploration.
Objective To explore the feasibilities, methods, outcomes and indications of atlas pedicle screw system fixation and fusion for the treatment of upper cervical diseases. Methods From October 2004 to January 2006, 17 patients with upper cervical diseases were treated with atlas pedicle screw system fixation and fusion. There were 13 males and 4 females, ageing 19 to 52 years. Of 17 cases, there were 14 cases of atlantoaxial dislocation(including 3 cases of congenital odontoid disconnection，4 cases of old odontoid fracture，2 cases of new odontoid fracture(typeⅡC), 3 cases of rupture of the transverse ligament, and 2 cases of atlas fracture； 2 cases of tumor of C2; 1case of giant neurilemoma of C2,3 with instability after the resection oftumors. JOA score before operation was 8.3±3.0. Results The mean operative time and bleeding amount were 2.7 hours (2.1-3.4 hours) and 490 ml (300-750 ml) respectively. No injuries to the vertebral artery and spinal cord were observed. The medial-superior cortex of lateral mass was penetrated by 1 C1 screw approximately 3 mmwithout affecting occipito-atlantal motions. All patients were followed up 3-18 months. The clinical symptoms were improved in some extents and the screws were verified to be in a proper position, no breakage or loosening of screw and rob occurred. All patients achieved a solid bone fusion after 3-6 months. JOA score 3 months after operation was14.6±2.2. JOA improvement rates were 73%-91%(mean 82%). Conclusion The atlas pedicle screw system fixation and fusion is feasible for the treatment of upper cervical diseases and has betteroutcomes, wider indications if conducted properly.
Objective To assess the possibility of placing the posterior pedicle screw on atlas. Methods Twenty human cadaver specimens were used to insert pedicle screws in atlas, through the posterior arch or the pedicle of C1 into the lateral mass. The screw entry point was on the posterior surface of C1 posterior arch and at the intersection of the vertical line through the center of C2 inferior articular process and the horizontal line at least 3 mm below the superior rim of the C1 lamina. The screw of 3.5 mm in diameter was placed in a direction of 10° medial angle and 5° upwardangle. After placement of C1 pedicle screw, the distance from C1 screw entry point to the mediallateral midpoint of C1 pedicle, the maximum length of screw trajectory and the actual screw trajectory angles were measured. The direction of screw penetrating through the cortical of C1 pedicle or lateral mass and the injuries to the vertebral artery and spinal cord were observed.Results Forty pedicle screws were placed on atlas, the mean distance from C1 screw entry point to the medial-lateral midpoint of C1 pedicle was (2.20±0.42)mm, the maximum length of screw trajectory averaged (30.51±1.59)mm, and the actual screw trajectory angle measured (9.7±0.67)° in a medial direction and (4.6±0.59) ° in a upward direction. Only 1 screw penetrated the upper cortical bone of the atlas pedicle because the upward angle was too large, and 8 screws were inserted so deep that the inferior cortical bone of the C1 lateral mass was penetrated. But no injuries to the vertebral artery and spinal cord wereobserved. Conclusion C1 posterior pedicle screw fixation is quite accessible and safe, but the su
ObjectiveTo investigate the accuracy of progressive three-dimensional navigation template system (abbreviated as progressive template) to assist atlas-axial pedicle screw placement. MethodsThe clinical data of 33 patients with atlas-axial posterior internal fixation surgery between May 2015 and May 2017 were retrospectively analyzed. According to the different methods of auxiliary screw placement, the patients were divided into trial group (19 cases, screw placement assisted by progressive template) and control group (14 cases, screw placement assisted by single navigation template system, abbreviated as initial navigation template). There was no significant difference in gender, age, cause of injury, damage segments, damage types, and preoperative Frankel classification between the two groups (P>0.05). The operation time and intraoperative blood loss of the two groups were compared. The safety of screw placement was evaluated on postoperative CT by using the method from Kawaguchi et al, the deviation of screw insertion point were calculated, the angular deviation of the nailing on coordinate systems XOZ, XOY, YOZ were calculated according to Peng’s method. ResultsAll patients completed the operation successfully; the operation time and intraoperative blood loss in the trial group were significantly less than those in the control group (t=–2.360, P=0.022; t=–3.006, P=0.004). All patients were followed up 12–40 months (mean, 25.3 months). There was no significant vascular injury or nerve injury aggravation. Postoperative immediate X-ray film and CT showed the dislocation was corrected. Postoperative immediate CT showed that all 76 screws were of grade 0 in the trial group, and the safety of screw placement was 100%; 51 screws were of grade 0, 3 of gradeⅠ, and 2 of gradeⅡ in the control group, and the safety of screw placement was 91.1%; there was significant difference in safety of screw placement between the two groups (χ2=7.050, P=0.030). The screw insertion point deviation and angular deviation of the nailing on XOY and YOZ planes in the trial group were significantly less than those in the control group (P<0.05). There was no significant difference in angular deviation of the nailing on XOZ between the two groups (t=1.060, P=0.290). ConclusionCompared with the initial navigation template, the progressive navigation template assisting atlas-axial pedicle screw placement to treat atlas-axial fracture with dislocation, can reduce operation time and intraoperative blood loss, improve the safety of screw placement, and match the preoperative design more accurately.
To evaluate the differential expression profiles of the lncRNAs, miRNAs, mRNAs and ceRNAs, and their implication in the prognosis in clear cell renal cell carcinoma (CCRCC), the large sample genomics analysis technologies were used in this study. The RNA and miRNA sequencing data of CCRCC were obtained from The Cancer Genome Atlas (TCGA) database, and R software was used for gene expression analysis and survival analysis. Cytoscape software was used to construct the ceRNA network. The results showed that a total of 1 570 lncRNAs, 54 miRNAs, and 17 mRNAs were differentially expressed in CCRCC, and most of their expression levels were up-regulated (false discovery rate < 0.01 and absolute log fold change > 2). The ceRNA regulatory network showed the interaction between 89 differentially expressed lncRNAs and 9 differentially expressed miRNAs. Further survival analysis revealed that 38 lncRNAs (including COL18A1-AS1, TCL6, LINC00475, UCA1, WT1-AS, HOTTIP, PVT1, etc.) and 2 miRNAs (including miR-21 and miR-155) were correlated with the overall survival time of CCRCC (P < 0.05). Together, this study provided us several new evidences for the targeted therapy and prognosis assessment of CCRCC.
Objective To analyze the expression of H2A histone family, member X (H2AFX) gene in lung adenocarcinoma and its influence on prognosis. Methods We analyzed the expression level of H2AFX gene in the tumor tissues (497 cases) and normal adjacent tissues (54 cases) of lung adenocarcinoma patients via The Cancer Genome Atlas. The patients were divided into high expression group and low expression group according to the expression level of H2AFX gene in lung adenocarcinoma samples. The relationship between H2AFX and clinicopathological features of patients was analyzed through logistic regression. Kaplan-Meier survival curve and log-rank test were used to study the correlation between H2AFX expression and the prognosis of lung adenocarcinoma patients. Univariate and multiple Cox regression analyses were performed to determine the prognostic significance of H2AFX expression in lung adenocarcinoma patients. The research also covered H2AFX-related pathways of genes in the development of lung adenocarcinoma with gene set enrichment analysis (GSEA). Results The H2AFX expression was higher in lung adenocarcinoma tissues than that in normal adjacent tissues (P<0.001). Besides, it was significantly correlated with age (P<0.001), T staging (P=0.007), and N staging (P=0.010), but had little to do with M staging or gender (P>0.05). Kaplan-Meier survival curve and log-rank test showed that the survival rate of patients with high H2AFX expression was vastly lower than that of patients with low H2AFX expression (P<0.001). Multiple Cox regression analysis demonstrated that H2AFX could be an independent prognostic factor for lung adenocarcinoma [hazard ratio=1.41, 95% confidence interval (1.11, 1.78), P=0.004]. The results of GSEA displayed that H2AFX was involved in cell cycle, homologous recombination, DNA replication, base excision and repair, spliceosome, mismatch repair, p53 signaling pathway, nucleotide excision and repair, RNA degradation, RNA polymerase, and other pathways. Conclusions The expression of H2AFX gene is high in lung adenocarcinoma, and closely connected to the prognosis, occurrence, and evolution of lung adenocarcinoma. This gene can be one of the new molecular markers and therapeutic targets for lung adenocarcinoma.
The Human Cell Atlas project is an international collaboration following the Human Genome Project, which aims to establish a reference map for the characterization of all human cells. Recent years, the project has brought together various different types of cell atlas, mostly focusing on the cell types of individual tissues and organs. Science published the latest research results of the Pan-tissue Human Cell Atlas on 12 May 2022, which integrates cell atlas of multiple tissues and organs in the human. It contributes to a more comprehensive understanding of disease pathogenesis, vaccine development, cell engineering, tumor immunity, and regenerative drug development.
ObjectiveTo screen long non-coding RNAs (lncRNAs) relevant to programmed cell death (PCD) and construct a nomogram model predicting prognosis of hepatocellular carcinoma (HCC). MethodsThe HCC patients selected from The Cancer Genome Atlas (TCGA) were randomly divided into training set and validation set according to 1∶1 sampling. The lncRNAs relevant to PCD were screened by Pearson correlation analysis, and which associated with overall survival in the training set were screened by univariate Cox proportional hazards regression (abbreviation as “Cox regression”), and then multivariate Cox regression was further used to analyze the prognostic risk factors of HCC patients, and the risk score function model was constructed. According to the median risk score of HCC patients in the training set, the HCC patients in each set were assigned into a high-risk and low-risk, and then the Kaplan-Meier method was used to draw the overall survival curve, and the log-rank test was used to compare the survival between the HCC patients with high-risk and low-risk. At the same time, the area under receiver operating characteristic curve (AUC) was used to evaluate the value of the risk score function model in predicting the 1-, 3-, and 5-year overall survival rates of HCC patients in the training set, validation set, and integral set. Then the nomogram was constructed based on the risk score function model and factors validated in clinic, and its predictive ability for the prognosis of HCC patients was evaluated. ResultsA total of 374 patients with HCC were downloaded from the TCGA, of which 342 had complete clinicopathologic data, including 171 in the training set and 171 in the validation set. Finally, 8 lncRNAs genes relevant to prognosis (AC099850.3, LINC00942, AC040970.1, AC022613.1, AC009403.1, AL355974.2, AC015908.3, AC009283.1) were screened out, and the prognostic risk score function model was established as follows: prognostic risk score=exp1×β1+exp2×β2...+expi×βi (expi was the expression level of target lncRNA, βi was the coefficient of multivariate Cox regression analysis of target lncRNA). According to this prognostic risk score function model, the median risk score was 0.89 in the training set. The patients with low-risk and high-risk were 86 and 85, 86 and 85, 172 and 170 in the training set, validation set, and integral set, respectively. The overall survival curves of HCC patients with low-risk drawn by Kaplan-Meier method were better than those of the HCC patients with high-risk in the training set, validation set, and integral set (P<0.001). The AUCs of the prognostic risk score function model for predicting the 1-, 3-, and 5-year overall survival rates in the training set were 0.814, 0.768, and 0.811, respectively, in the validation set were 0.799, 0.684, and 0.748, respectively, and in the integral set were 0.807, 0.732, and 0.784, respectively. The multivariate Cox regression analysis showed that the prognostic risk score function model was a risk factor affecting the overall survival of patients with HCC [<0.89 points as a reference, RR=1.217, 95%CI (1.151, 1.286), P<0.001]. The AUC (95%CI) of the prognostic risk score function model for predicting the overall survival rate of HCC patients was 0.822 (0.796, 0.873). The AUCs of the nomogram constructed by the prognostic risk score function model in combination with clinicopathologic factors to predict the 1-, 3-, and 5-year overall survival rates were 0.843, 0.839, and 0.834. The calibration curves of the nomogram of 1-, 3-, and 5-year overall survival rates in the training set were close to ideal curve, suggesting that the predicted overall survival rate by the nomogram was more consistent with the actual overall survival rate. ConclusionThe prognostic risk score function model constructed by the lncRNAs relevant to PCD in this study may be a potential marker of prognosis of the patients with HCC, and the nomogram constructed by this model is more effective in predicting the prognosis (overall survival) of patients with HCC.