Objective To compare the stability effect of the fixation segment using the new test system based robotics to simulate the complex human movement at natural state about the three-level fixa-tion by using four, five or six pedicle screws in treatment of thoracolumbar burst fractures. Methods Six human cadaveric spines were dissected from T_(11)-L_3. The inferior half part of L_1 vertebral bodies and L_1-L_2 dises were resected to mimie an unstable L_1 burst fracture with loss of anterior column support. Specimens were tested in accordance with the following order:intact, 4,5 and 6 pedicle screws fixation at the three-level fixation. The range of motion (ROM) of the fixation segment (T_(11)-L_3) was measured with the six-freedom degree robotics system controlled by mixed force and displacement during flexion, exten-sion, lateral bending and axial torsion, when the stiffness was calculated. One-way statistieal analysis was used for analyzing the collected data. Results With increased number of screws, the ROM of the fixa-tion segment (T_(11)-L_3) was gradually decreased and the stiffness gradually increased. The ROM under ax-ial rotation of six and five screws group became smaller than four screws group (P < 0.05). The stiffness under axial rotation of six screws group was higher than four screws group (P < 0.05). There was no sta-tistical difference between five screws group and four screws group in regard of the stiffness in axial rota-tion (P > 0.05). There were no significant differences in ROM and stiffness under six different loading directions between six screws group and five screws group (P > 0.05). No statistical difference was observed for three fixation modes in aspects of ROMs and stiffness under flexion-extension or lateral ben-ding (P > 0.05). Conclusions Three-level fixation of burst fractures with five or six screws offers im-proved biomechanical stability compared with traditional four screws fixation. But the difference is insig-nificant between six and five screws fixations.

Objective:To explore the evolution of CT characteristics of the "reversed halo sign" of pulmonary tuberculosis, and to further improve the recognition of its CT signs.Methods:Clinical and CT data of 12 patients with pulmonary tuberculosis who were clinically and pathologically confirmed and accompanied with CT manifestation of "reversed halo sign" in First Affiliated Hospital of Henan University of Science and Technology from August 2013 to April 2020 were analyzed retrospectively. Pathological and imaging contrastl analysis was performed on 1 patient undergoing surgical treatment.Results:Among 12 cases with "reversed halo sign", there were 2 cases with single lesion in unilateral lung, 2 cases with multiple lesions in unilateral lung, and 8 cases with multiple lesions in bilateral lungs. Three cases showed only "reversed halo sign", 9 cases showed both halo-like sign and uniform fireworks sign. "Tree-in-bud "sign was found in all 12 patients in the outer ring of the "reversed halo sign". Eight patients received three or more CT examinations, and six of them showed reduction of density and volume of the "reversed halo sign" after standardized anti-tuberculosis treatment. Under the natural course of the disease in two cases, the overall enlargement of the lesion was observed in 1 case, and the overall density of the lesion was reduced and the outer ring wall of the "reversed halo sign" was thinned in 1 case. The pathology of one case after surgical lobectomy showed granulomatous inflammatory nodules of varying sizes containing Langerhans nodule giant cells in the lung parenchyma. The typical caseous necrotic granulomatous nodules were rare here. The "reversed halo sign" showed dense Langerhans nodules in the outer ring, sparse central areas with fibrous hyperplasia and alveolar wall thickening.Conclusions:The outer ring of "reversed halo sign" of pulmonary tuberculosis shows as "tree-in-bud" sign, and its center shows as the fine reticulation pattern. After effective anti-tuberculosis treatment, both the overall density of "reversed halo sign" and the lesion size reduced. Finally, the lesions mostly present as as fine grid shadows for a long time.

OBJECTIVES: Laryngeal squamous cell carcinoma (LSCC) is a common malignant tumor of head and neck. Screening of target genes for malignant tumor therapy is one of the focuses of cancer research, with proto-oncogene and tumor suppressor gene as the breakthrough. It has become an urgent need to find the target gene related to the treatment and prognosis of LSCC.This study aims to explore the role of Lin28B and C-myc in LSCC by detecting the expressions of these two proteins and analyze the correlation between the expression of Lin28B and C-myc and clinicopathological features and prognosis of LSCC. METHODS: We detected the expression of Lin28B and C-myc proteins in 102 specimens of LSCC and 90 specimens of adjacent tissues by immunochemistry, and analyzed the correlation between Lin28B and C-myc protein expressions in LSCC as well as the correlation between the expressions of the two proteins and the clinicopathological features of LSCC. At the same time, the Kaplan-Meier method was used to analyze the relation between Lin28B and C-myc protein levels with the postoperative survival rate of LSCC patients. RESULTS: The protein levels of Lin28B and C-myc in the LSCC tissnes were significantly higher than those in the adjacent tissues (both P<0.05),and there was a positive correlation between the expression of Lin28B and C-myc in LSCC (r＝0.476, P<0.05). The expression of Lin28B protein was closely related to age, lymph node metastasis, clinical stage, tumor size, and pathological differentiation of LSCC patients (all P<0.05). while the expression of C-myc protein was closely related to lymph node metastasis, clinical stage, tumor size, and pathological differentiation of LSCC patients (all P<0.05). A relevant survival analysis showed that in patients with higher level of Lin28B (P＝0.001) or C-myc protein (P<0.001), the postoperative survival rate was relatively low. CONCLUSIONS Lin28B and C-myc proteins are highly expressed in LSCC with a positive correlation. Furthermore, they are closely related to lymph node metastasis, clinical stage, tumor size, pathological differentiation and prognosis, suggesting that both Lin28B and C-myc might be involved in the occurrence and development of LSCC.
Humans ; Squamous Cell Carcinoma of Head and Neck ; Proto-Oncogene Proteins c-myc/metabolism* ; Laryngeal Neoplasms/diagnosis* ; Carcinoma, Squamous Cell/genetics* ; Lymphatic Metastasis ; Prognosis ; Head and Neck Neoplasms ; Biomarkers, Tumor/metabolism* ; RNA-Binding Proteins/genetics*