BACKGROUND: Atlantoaxial posterior approach is currently the main surgical treatment for atlantoaxial instability and/or dislocation, but the shape of rod in normal screw-rod device system is cylindrical. To obtain satisfactory reduction of atlantoaxis, the rod will be pre-bent obviously before fixation; however, the cylindrical rod will be rotated when tighten the nuts. Extra devices will be required to adjust and maintain the direction of the rod, thereafter, the surgical field will be blocked by the device, and spinal injury will occur once the devices are not held tightly. While the novel automatic anti-rotation rod has the function of anti-rotation during nut-tightening process, and also holds all the advantages of normal rod. Further research should be performed for the differences in biomechanical characteristics between two methods.OBJECTIVE: To investigate the biomechanical properties of the novel automatic anti-rotation rod for internal fixation system of atlantoaxial posterior approach based on three-dimensional finite-analysis model of upper cervical spine.METHODS: The three-dimensional finite element model of upper cervical spine with internal rod fixation system was developed. The biomechanical characteristics of the internal fixation system were analyzed. RESULTS AND CONCLUSION: The traditional and novel three-dimensional finite element model with realistic and geometric similarity contained 198330 elements, 964747 nodes and 246788 elements, 996069 nodes,correspondingly. There was no obvious stress concentration in both two systems, stress was concentrated mainly in the screw-bone and screw-rod interfaces. The stress values of the novel system were higher than those of the traditional system, but the maximum Von Misses Stress of two systems was lower than the yield (795-827 MPa ) and ultimate (860-896 MPa) strength of titanium alloys. These results show that the design of the novel automatic anti-rotation rod-screw fixation system has matched the biomechanical requirements for new internal fixation instruments, and is one safe, effective and practical device for atlantoaxial posterior procedure showing promising application prospect.

Objective:To preliminarily study the immune response mediated by inducible costimulation molecule in the role of essential hypertensive renal damage .Methods: The blood pressure of spontaneously hypertensive rats and the wild control group (Wistar-Kyoto rats)was dynamically monitored by noninvasive tail artery blood pressure measuring instrument .The urine protein of the rats in 24 hours was dynamically detected by ELISA .The levels of ICOS protein and its mRNA in the rat′s kidneys were dynamically detected by immunohistochemistry , RT-PCR, respectively.The levels of IL-17A and TGF-β1 in the rat′s plasma and kidneys were dynamically detected by ELISA ,immunohistochemistry ,respectively.The renal pathological changes of the rats were detected by HE and MASSON staining.Results:The blood pressure and urine protein in 24 h of SHRs were significantly higher than that of group WKY from 6 weeks.The expression of ICOS protein and its mRNA in SHRs were significantly higher than that of WKY rats from 6 weeks,and there are significantly positive correlations between the dynamic change of ICOS protein and its mRNA and renal fibrosis score of SHRs (rA=0.813,PA<0.05;rB=0.753,PB<0.05).The expression of IL-17A and TGF-β1 in SHR′s plasma and kidneys were significantly higher than that of WKY rats at the weeks 10 and 23.HE and Masson staining showed that the degree of renal fibrosis of SHRs was sig-nificantly higher than that of WKY rats at 23 weeks.Conclusion:The immune response mediated by ICOS plays an important role in hypertensive renal damage .

In the present study, the total RNA was extracted from three instar larvae of Musca domestica, the cDNA sequence encoding the ORF of cecropins was amplified by RT-PCR, and the target fragment was further sequenced after being cloned into T vector pUCm-T. Then, the cDNA sequence of the mature cecropins was amplified by PCR with recombinant plasmid pUCm-T/cecropin as template, the N-terminal rare codon GGA of E. coli was changed to the favorable codon GGC,and a Asn codon AAC was added in front of the stop coden TAA in the C- terminus. This mutant gene designated as mCecropin was then ligated with the fusion expression vector pGEX-4T-1. After restriction analysis and DNA sequencing, the positive recombinant plasmid pGEX-4T-1/mCecropin was transformed to different strains of E. coli cells and the fusion protein was expressed after IPTG induction. The fusion protein was assayed by SDS-PAGE and the E. coli BL21(DE3) cell was chosen as the host cell for the expression of the fusion protein. The expressed fusion protein GST-mCecropin was purified by GSTrap affinity coloum and the GST marker was then cleaved by thrombin. In this way, the fusion protein mCecropin with antibacterial activity was obtained after purification with HiTrap benzamidine column.

The BPI23-haFGF fusion gene was subcloned to the yeast expression vector pPICZaA and the recombinant plasmid pPICZaA-BPI23-haFGF was constructed. After linearization by sac I, the construct was introduced into X-33 yeast cells. The efficient engineering strain was obtained by the resistance and phenotype selection and identified by specific PCR. SDS-PAGE and Western blot analysis indicated that a 43 KD protein band coincident with the anticipated fusion protein size expressed in the culture supernatant of the transformed yeast cells, which accounted for above 50% of the total proteins of the culture supernatant. About 90% purity of recombinant BPI23-haFGF fusion protein was obtained by affinity chromatography. The in vitro bioactivity testing showed that the purified fusion protein killed E. coli and promoted proliferation of NIH3T3 cells, suggesting that the recombinant BPI23-haFGF fusion protein possessed both of BPI and FGF functions.
Animals ; Antimicrobial Cationic Peptides ; genetics ; metabolism ; Blood Proteins ; genetics ; metabolism ; Cell Proliferation ; Cloning, Molecular ; Escherichia coli ; drug effects ; Fibroblast Growth Factor 1 ; genetics ; metabolism ; Gene Fusion ; Genetic Vectors ; Humans ; Mice ; NIH 3T3 Cells ; Pichia ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism ; pharmacology

BACKGROUND:Posterior atlantoaxial pedicle screw rod internal fixation is the main method for treating atlantoaxial dislocation,and the horizontal crosslink plays an important role in the antirotation ability of the internal fixation system.The new horizontal screw-screw crosslink can effectively overcome the disadvantages of traditional horizontal crosslink,such as inconvenient installation,impact on bone grafting bed,and potential spinal cord injury.However,the biomechanical properties of the new horizontal screw-screw crosslink with different installation modes are still unclear. OBJECTIVE:To investigate the biomechanical characteristics of new different installation modes of horizontal screw-screw crosslink in the C1-C2 pedicle screw-rod fixation and to provide a theoretical basis for optimal installation mode. METHODS:Six fresh human occipitocervical specimens were divided into the intact state group(group A),and the atlantoaxial instability model of type Ⅱ odontoid fracture was established based on the intact state group as the instability group(group B).The C1-C2 pedicle screw-rod fixation was performed on each specimen based on the instability group(group C).In group C,different installation modes of horizontal screw-screw crosslink were successively installed in each specimen,including upper transverse connection(two atlas screw tails)as group D,lower transverse connection(two axis screw tails)as group E,diagonal transverse connection(upper left and lower right for group F,lower left and upper right for group G),and cross transverse connection as group H.The specimen models were tested in order of flexion,extension,lateral flexion and lateral rotation on a three-dimensional motion machine,and the atlantoaxial range of motion of each group of specimens was obtained.Repeated measure analysis of variance was used to evaluate the biomechanical properties of each group. RESULTS AND CONCLUSION:(1)Under six states,the range of motion of groups A,C,D,E,F,G and H was smaller than that of group B,and there were statistically significant differences(P＜0.05).(2)In the flexion and extension states,there was no significant difference among the five types of horizontal screw-screw crosslink groups(P＞0.05).(3)In the left and right rotation directions,there were significant differences in D and E groups compared with F,G and H groups(P＜0.05);there were no significant differences between D and E groups,and F and G groups(P＞0.05),and there were no significant differences in F and G groups compared with H group(P＞0.05).(4)In conclusion,under flexion-extension states,the biomechanical stability of five types of horizontal screw-screw crosslink groups was similar,but under the rotation state,the stability of diagonal horizontal screw-screw crosslink group and cross horizontal screw-screw crosslink group was obviously better than that of transverse horizontal screw-screw crosslink group;however,the stability of diagonal horizontal screw-screw crosslink group is similar to the cross horizontal screw-screw crosslink group,so the former is more worthy of clinical recommendation.

Objective:To evaluate the preliminary clinical application of our self-designed posterior reduction forceps for atlantoaxial dislocation in the reduction and fixation of irreducible atlantoaxial dislocation with simple posterior screw-rod system.Methods:Our posterior reduction forceps was self-designed and developed to assist simple posterior screw-rod system in the treatment of irreducible atlantoaxial dislocation based on the posterior atlantoaxial screw-rod system. A retrospective study was conducted to analyze the clinical data of 5 patients with irreducible atlantoaxial dislocation who had been treated from January 2021 to October 2022 at Department of Spine Surgery, General Hospital of Southern Theatre Command of PLA with our self-designed posterior reduction forceps. There were 2 males and 3 females, aged 53, 62, 45, 32 and 48 years, respectively. Diagnosis: 1 case of free odontoid process combined with atlantoaxial dislocation, 2 cases of atlantoaxial dislocation, and 2 cases of old odontoid process fracture combined with atlantoaxial dislocation. Respectively, their preoperative Japanese Orthopaedic Association (JOA) scores were 9, 11, 12, 13 and 10 points and their atlanto-dental intervals (ADI) 9.8, 7.4, 6.6, 6.4 and 8.5 mm. Postoperatively, atlantoaxial reduction and spinal cord compression were evaluated by X-ray, CT, and MRI examinations, and internal fixation, atlanto-axial sequence, and bone graft fusion by X-ray and CT examinations. One week after surgery, the JOA scores were used to evaluate the patients' neurological function and the ADI was measured to evaluate the atlantoaxial reduction.Results:The surgery was successfully performed in the 5 patients, with no intraoperative complications like neurovascular injuries to the spinal cord. The postoperative atlantoaxial reduction was satisfactory, the position of internal fixation was good, the compression to the spinal cord was relieved, and the clinical symptoms were significantly improved. At 1 week after surgery, respectively, the JOA score: 13, 14, 14, 15 and 13; the ADI: 2.6, 2.1, 1.8, 1.5 and 2.2 mm; the follow-up time: 3, 6, 12, 9 and 6 months; the bone fusion time: 3, 3, 6, 6 and 3 months. Follow-ups revealed no loosening or fracture of internal fixation, good atlanto-axial sequence, and no recurrence of dislocation.Conclusion:Our self-designed posterior reduction forceps for atlantoaxial dislocation can assist the simple posterior screw-rod system to treat irreducible atlantoaxial dislocation, leading to good preliminary clinical outcomes.

Objective To investigate the clinical effect of posterior screw-rod fixation fusion for the treatment of atlantoaxial dislocation due to rheumatoid arthritis.Methods From January 2011 to December 2015,15 patients with atlantoaxial dislocation due to rheumatoid arthritis were treated,including 6 males and 9 females,aged 35 to 75 years (mean 55 years).All cases were evaluated about the difficulty of relocation by extension-flexion X-ray and treated with posterior screw-rod reduction,fixation and autogenous bone grafting under general anesthesia.Atlantodental interval (ADI) was measured and collected before and after surgery.Visual Analogue Scale/Score (VAS),American Spinal Cord Injury Association (ASIA) and Japanese Orthopaedic Association (JOA) scores were comprehensively used to evaluate the clinical effect.1 week,3,6,12 months postoperatively and the annual review of the X-ray and CT were checked,in order to evaluate the reduction,internal fixation and bone graft fusion.Results All patients were reducible dislocation and successfully performed the posterior screw-rod fixation fusion surgery.The patients were followed up for 3 to 24 months (average,15 months).Atlantoaxial solid bony fusion was obtained from 3 to 6 months.ADI reduced from preoperative 6.3±1.7 mm to postoperative 2.2±0.8 mm,VAS score reduced from preoperative 5.4±2.7 to postoperative 1.7±1.0,ASIA motor score improved from preoperative 82.3±15.6 to 95.3±4.5 at 6 months after the surgery,JOA score increased from preoperative 13.8±2.9 to 15.5±1.4 at 6 months after the surgery,and the statistical significance was revealed between preoperation and postoperation.Nine cases were in D grade of ASIA,3 cases improved from D to E grade after surgery,2 cases reached E grade in the other 6 cases after 6 months,2 cases recovered to E grade after 12 months and other 2 cases in D grade got uniformity after surgery.Well internal fixation and no redislocation were found on X-ray and CT during follow-up period.Conclusion Atlantoaxial dislocation because of rheumatoid arthritis was numerously reducible genre.Posterior screw-rod fixation and autogenous bone grafting can gain satisfying clinical efficacy.

BACKGROUND:The addition of traditional rod-rod fixation for atlantoaxial joint disease to C1-C2 pedicle screw-rod fixation(C1-C2 PSR)can provide stronger anti-rotation stability for screw/rod fixation,but there is a risk of installation difficulties,impact on bone graft bed,and spinal cord injury.The new horizontal screw-screw crosslink(hS-S CL)designed by the authors can effectively overcome the above shortcomings,but its biomechanical properties are unclear. OBJECTIVE:To analyze biomechanical properties of new horizontal screw-screw crosslink in C1-C2 PSR by three-dimensional finite element analysis. METHODS:CT thin layer scanning data were collected from the occipital base to the axis(C0-2)of one adult healthy male volunteer.The atlantoaxial finite element models were established respectively:the normal group,the unstable group,the non-crosslink group(unstable+C1-C2 PSR),and the crosslink group(C1-C2 PSR+hS-S CL).Range of motion and Von Miss Stresses in flexion and extension,lateral flexion and rotation of the four groups were calculated by applying 1.5 Nm torque to each finite element model,and the stress cloud was extracted. RESULTS AND CONCLUSION:(1)Range of motion of the unstable group was increased by 43.8%-78.7%compared with the normal group,and the range of motion of the internal fixation groups was 90.2%-98.7%lower than that of the unstable group under six conditions.The range of motion of the crosslink group and the non-crosslink group was basically the same in flexion and extension states,but in lateral flexion and rotation states,the range of motion of the crosslink group decreased 34.3%-43.8%and 78.6%-79.1%,respectively,compared with the non-crosslink group,and range of motion decreased most obviously in rotation state.(2)The stress peak of the internal plant model:The maximum stress of the crosslink group was generally smaller than that of the non-crosslink group,and the stress peak value of all the internal fixation groups was the lowest when the extension was carried out.(3)The stress cloud of internal plants showed that there was no obvious stress concentration phenomenon in the internal fixation,and the main stress distribution areas were the screw root and bone joint,and the crosslink ends were the screw tail groove or the joint rod joint.(4)The new horizontal screw-screw crosslink can obviously improve the anti-rotation stability of internal fixation and it can share part of the pressure in the three-dimensional motion direction of the internal fixation system and reduce the maximum stress of the internal plants.However,the stress distribution is obvious at both ends of the crosslink,and this part may be prone to fracture of the crosslink.

Objective:To subdivide clinical classification of refractory atlantoaxial dislocation, and evaluate the reliability of new subdivide clinical classification of refractory atlantoaxial dislocation.Methods:From January 2010 to December 2018, 48 patients with refractory atlantoaxial dislocation were treated, including 19 males and 29 females, aged 16 to 65 years, with an average of 39.2±13.3 years. According to the changes of relative anatomical position of C 1 and C 2 under general anesthesia with heavy traction of 1/6 body weight, subdivide clinical classification of refractory atlantoaxial dislocation were proposed, and refractory atlantoaxial dislocation was divided into traction loosening type (atlantoaxial angle≥5°) and traction stabilization type (atlantoaxial angle<5°). The traction loosening type was directly reduced by posterior atlantoaxial screw-rod fixation and fusion without anterior or posterior soft tissue release. For traction stabilization type, transoral soft tissue release was performed first, and then transoral anterior reduction plate fixation and fusion or posterior atlantoaxial screw-rod fixation and fusion were performed. Atlantodental interval (ADI) and atlantoaxial angle (AAA) were measured and collected before and after surgery to evaluate atlantoaxial reduction. The space available for the spinal cord (SAC) were measured to evaluate spinal cord compression. Visual analogue score (VAS) was used to evaluate the neck pain levels, and Japanese Orthopaedic Association (JOA) scores was used to evaluate the neurological function. American Spinal Cord Injury Association impairment scale (AIS) was used to evaluate the degree of spinal cord injury. One week, 3, 6, 12 months postoperatively and the annual review of the X-ray and CT scan were checked, in order to evaluate the reduction, internal fixation and bone graft fusion. Results:Among all 48 cases, 22 cases were traction loosening type, of which posterior atlantoaxial screw-rod fixation and fusion were performed in 16 cases and occipitocervical fixation and fusion in 6 cases. 26 cases were traction stabilization type, and they all underwent anterior transoral release, and then, anterior TARP fixation and fusion were performed in 24 cases and posterior screw-rod fixation and fusion in the other 2 cases. X-ray, CT and MRI images and of all patients 1 week after surgery showed good atlantoaxial reduction and decompression of spinal cord. In each of the two types, there was one case lost to follow-up. For 46 cases in follow-up, the follow-up time ranged from 6 to 72 months, with an average of 38.0±17.2 months. Among 46 cases, 21 cases of traction loosening type showed that, ADI reduced from preoperative 9.9±2.2 mm to 2.3±0.9 mm at 3 months after surgery and 2.3±1.0 mm at the last follow-up, AAA increased from preoperative 57.9°±12.3° to 91.0°±2.2° at 3 months after surgery and 90.9°±2.2° at the last follow-up, SAC increased from preoperative 9.8±1.3 mm to 15.1±0.7 mm at 3 months after surgery and 14.9±0.7 mm at the last follow-up, VAS score reduced from preoperative 1.5±2.1 to 0.7±1.0 at 3 months after surgery and 0.3±0.6 at the last follow-up, and JOA score increased from preoperative 10.2±1.7 to 13.3±1.3 at 3 months after surgery and 14.9±1.5 at the last follow-up. Twenty-five cases of traction stabilization type presented that, ADI reduced from preoperative 9.7±2.0 mm to 2.1±1.4 mm at 3 months after surgery and 2.1±1.3 mm at the last follow-up, AAA increased from preoperative 55.8°±9.2° to 90.9°±1.4° at 3 months after surgery and 90.9°±1.3° at the last follow-up, SAC increased from preoperative 10.5±1.0 mm to 15.4±0.5 mm at 3 months after surgery and 14.8±2.8 mm at the last follow-up, VAS score reduced from preoperative 1.7±2.1 to 0.7±0.9 at 3 months after surgery and 0.3±0.5 at the last follow-up, and JOA score increased from preoperative 10.1±1.3 to 12.9±1.5 at 3 months after surgery and 14.4±1.3 at the last follow-up. In the traction loosening type, all the 10 grade D patients were improved to grade E at the last follow-up. In the 2 grade C patients of traction stabilization type before surgery, 1 patient was improved to grade E, 1 patient was improved to grade D, and all 11 patients with grade D were improved to grade E at the last follow-up. Bony fusion was obtained in all patients from 3 to 6 months, with an average of 4.4±1.5 months. During follow-up period, no looseness of internal fixation or redislocation happened.Conclusion:Refractory atlantoaxial dislocation can be divided into traction loosening type and traction stabilization type. For traction loosening type, satisfactory reduction can be achieved by using posterior atlantoaxial screw-rod system without soft tissue release. For traction stabilization type, anterior release is preferable, and then anterior TARP or posterior screw-rod can be used to achieve satisfactory reduction.

Objective To explore the effects of information-motivation-behavioral (IMB) skills model based WeChat education on the treatment compliance, the self-efficacy and the quality of life of diabetic nephropathy patients.Methods A total of 92 patients with diabetic nephropathy treated in Danyang People's Hospital from January 2015 to June 2016 were selected as the research object by convenient sampling method and randomly divided into observation group and control group according to the random number table, with 46 cases in each. The control group received conventional WeChat health education, and the observation group implemented WeChat health education based on IMB model. The treatment compliance, the self-efficacy and the quality of life were compared between the two groups 6 months after the nursing intervention. Results There was no statistically significant difference between the two groups of all dimensions and the total scores of treatment compliance before intervention (P>0.05). All the dimensions of treatment compliance of the observation group were higher than those of the control group after intervention, and the differences were statistically significant (t=3.365, 3.258, 3.989, 2.655, 3.513, 4.674, 3.747, 4.187,3.578;P<0.01). The change degree of the 10 dimensions of self-efficacy and total scores were all greater than those of control group, the differences were statistically significant (t=4.854, 5.632, 4.854, 4.241,3.896, 3.785, 3.789, 3.325, 3.314, 3.817,4.123;P<0.01). The improvement of all the dimensions of patients' life quality and its total score were all higher than the control group after intervention, with significant statistical difference (t=5.965, 4.763, 4.746, 4.547, 3.869;P<0.01).Conclusions Application of IMB model based WeChat health education on diabetic nephropathy patients can significantly improve the patient's treatment compliance, self-efficacy and quality of life.