SARS-CoV-2 Omicron: Viral Evolution, Immune Evasion, and Alternative Durable Therapeutic Strategies.

Since the SARS-CoV-2 Omicron virus has gained dominance worldwide, its continual evolution with unpredictable mutations and patterns has revoked all authorized immunotherapeutics. Rapid viral evolution has also necessitated several rounds of vaccine updates in order to provide adequate immune protection. It remains imperative to understand how Omicron evolves into different subvariants and causes immune escape as this could help reevaluate the current intervention strategies mostly implemented in the clinics as emergency measures to counter the pandemic and, importantly, develop new solutions. Here, we provide a review focusing on the major events of Omicron viral evolution, including the features of spike mutation that lead to immune evasion against monoclonal antibody (mAb) therapy and vaccination, and suggest alternative durable options such as the ACE2-based experimental therapies superior to mAbs to address this unprecedented evolution of Omicron virus. In addition, this type of unique ACE2-based virus-trapping molecules can counter all zoonotic SARS coronaviruses, either from unknown animal hosts or from established wild-life reservoirs of SARS-CoV-2, and even seasonal alpha coronavirus NL63 that depends on human ACE2 for infection.

Better clinical outcomes and return to sport rates with additional medial meniscus root tear repair in high tibial osteotomy for medial compartmental knee osteoarthritis.

PURPOSE: This retrospective study aimed to investigate whether the repair of medial meniscus posterior root tears (MMPRTs) is effective for improving clinical outcomes and return to sports rates in young patients (50 years old or younger) with medial compartment knee osteoarthritis (KOA) and MMPRTs. METHODS: Between 2016 and 2019, 153 patients with KOA and MMPRTs who underwent open-wedge high tibial osteotomy (OWHTO) were retrospectively included. The patients were divided into OWHTO combined with MMPRT repair (n = 73) and isolated OWHTO (n = 80) groups. Lysholm scores, Hospital for Special Surgery (HHS) scores, Tegner scores, flexion contracture, range of knee flexion, return to sports rates and postoperative complications were compared. Radiological outcomes, including hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), joint line convergence angle (JLCA) and Kellgren-Lawrence (K-L) grade, were compared between the two groups. RESULTS: After a mean follow-up of 30.1 ± 3.0 months, the OWHTO + Repair group observed better clinical outcomes compared with the OWHTO group (Lysholm score: 86.7 ± 7.4 vs. 81.6 ± 6.9, p = 0.023. HHS score: 85.4 ± 8.20 vs. 80.5 ± 7.1, p = 0.039). The OWHTO + Repair group had higher Tegner scores and return to sports rates than the OWHTO group (Tegner score: 6 vs. 5, p = 0.020; return to sports rates: 38% vs. 15%, p = 0.001). No fracture or major complications occurred. Radiological outcomes showed no significant differences between the two groups (HKA: 181.1 ± 2.7 vs. 180.1 ± 1.5 n.s; MPTA: 90.1 ± 1.8 vs. 89.2 ± 1.4, n.s; JLCA:1.9 ± 0.7 vs. 2.1 ± 0.7, n.s). CONCLUSIONS: Additional MMPRT repair during OWHTO was associated with better clinical outcomes and higher rates of return to sports in young patients with medial compartment KOA and MMPRTs. LEVEL OF EVIDENCE: Level III.

The synthetic NLR RGA5HMA5 requires multiple interfaces within and outside the integrated domain for effector recognition.

Some plant sensor nucleotide-binding leucine-rich repeat (NLR) receptors detect pathogen effectors through their integrated domains (IDs). Rice RGA5 sensor NLR recognizes its corresponding effectors AVR-Pia and AVR1-CO39 from the blast fungus Magnaporthe oryzae through direct binding to its heavy metal-associated (HMA) ID to trigger the RGA4 helper NLR-dependent resistance in rice. Here, we report a mutant of RGA5 named RGA5HMA5 that confers complete resistance in transgenic rice plants to the M. oryzae strains expressing the noncorresponding effector AVR-PikD. RGA5HMA5 carries three engineered interfaces, two of which lie in the HMA ID and the other in the C-terminal Lys-rich stretch tailing the ID. However, RGA5 variants having one or two of the three interfaces, including replacing all the Lys residues with Glu residues in the Lys-rich stretch, failed to activate RGA4-dependent cell death of rice protoplasts. Altogether, this work demonstrates that sensor NLRs require a concerted action of multiple surfaces within and outside the IDs to both recognize effectors and activate helper NLR-mediated resistance, and has implications in structure-guided designing of sensor NLRs.

Morphological Changes of the Posterior Femoral Condyle After Medial Patellar Retinaculum Plasty in Skeletally Immature Patients With Recurrent Patellar Dislocation and Trochlear Dysplasia.

Background: Surgical correction for recurrent patellar dislocation (RPD) can improve femoral trochlear morphology; nonetheless, the effects of surgical correction on femoral condyle morphology are unclear. Purpose: To investigate the morphological changes in the posterior femoral condyle in skeletally immature patients with RPD and trochlear dysplasia (TD) after surgical correction. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 20 skeletally immature patients with bilateral RPD and TD were included in this study. For each patient, the knee that was dislocated more frequently or had sustained a recent injury was treated with medial patellar retinaculum plasty (group S; n = 20 knees), and the asymptomatic or only occasionally dislocated contralateral knee was treated conservatively (group C; n = 20 knees). The lengths of the anterior medial and lateral femoral condyles and the lengths of the posterior medial and lateral femoral condyles were evaluated preoperatively and at the final follow-up. Trochlear morphological characteristics, tibial tuberosity-trochlear groove distance, and patellar tilt angle were compared between preoperative and final follow-up values with the 2-sample paired Student t test and were compared between groups S and C with the independent-samples t test. Results: The mean follow-up time was 60.7 ± 4.8 months. No knee in group S experienced a redislocation, whereas 80% (16/20) of knees in group C experienced a dislocation. There were significant group differences in the ratio of the posterior medial femoral condyle (PMFC) to the posterior lateral femoral condyle (PLFC) (group S, 1.08 ± 0.05; group C, 1.14 ± 0.06; P = .042). There was no significant difference in the ratio of the anterior lateral femoral condyle to the anterior medial femoral condyle (group S, 1.16 ± 0.13; group C, 1.18 ± 0.09; P = .635). In group S, all trochlear morphological characteristics and patellofemoral joint characteristics improved compared with preoperatively (P≤ .047 for all). In addition, all values significantly differed between groups S and C at the final follow-up (P≤ .044 for all). Conclusion: The study findings demonstrated that the morphology of the posterior femoral condyle in skeletally immature patients with bilateral RPD and TD changes after surgical correction, with the PLFC growing faster than the PMFC.

Posterior fixation, anterior debridement and bone grafting in the treatment of thoracic and lumbar tuberculosis in children younger than 3 years of age.

PURPOSE: This study aimed to investigate the clinical outcomes of posterior fixation, combined with one- or two-stage anterior debridement and bone grafting in treating children younger than 3 years of age with thoracic and lumbar tuberculosis. METHODS: This was a retrospective study involving 16 young children with thoracic or lumbar tuberculosis. Surgical data were recorded. Frankel Grade was used to assess neurological function. The regional kyphosis angle was measured to evaluate the deformity correction. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were detected to assess the activity of tuberculosis. Bony fusion and complications were also recorded. RESULTS: The mean operation time was 204.4 ± 41.8 min. The mean estimated blood loss was 126.3 ± 94.4 ml. Preoperative Frankel Grade results indicated five patients with Grade C, six with Grade D, and five with Grade E. At the final follow-up, all patients were in Grade E. Twelve patients were brought back to normal spinal alignment and the rest four patients remained kyphotic. There was an improvement of 29.3° ± 18.3° in regional kyphotic angle postoperatively. And the deformity correction was 27.4° ± 19.1° at the final follow-up. ESR and CRP decreased to a normal range at three months follow-up. Bony fusion was achieved in all patients. None of the cases developed fixation failure, pseudoarthrosis, or tuberculosis recurrence. CONCLUSION: Posterior fixation, combined with one- or two-stage anterior debridement and bone grafting, is a safe and effective surgical strategy for treating young children with thoracic and lumbar tuberculosis.

Percutaneous endoscopic lumbar discectomy for single and double segment lumbar disc herniation with sciatic scoliosis in adults: a retrospective study.

OBJECTIVE: Sciatic scoliosis can be seen in patients with lumbar disc herniation. Percutaneous endoscopic lumbar discectomy (PELD) is a common surgical method for the treatment of lumbar disc herniation. The difference between single-segment lumbar disc herniation and double-segment lumbar disc herniation with Sciatic Scoliosis in adults after PELD needs further study. The aim of this study was to compare the imaging features of single-segment and double-segment lumbar disc herniation with Sciatic Scoliosis in adults and to further explore the clinical outcomes of functional improvement and scoliosis imaging parameters of the two groups after PELD. METHODS: Adult patients with lumbar disc herniation with sciatic scoliosis who received PELD from January 2019 to June 2022 were analyzed retrospectively. According to the number of operative segments, the patients were divided into a single-segment group and a double-segment group. Perioperative parameters were observed and compared between the two groups. The Visual Analogue Scale (VAS) score, Oswestry dysfunction index (ODI), Japanese Orthopaedic Association scores (JOA) and imaging parameters of the two groups were recorded and compared before the operation and during the follow-up. RESULTS: A total of 53 patients with single segments and 21 patients with double segments were included in this study. During the follow-up, the VAS score, ODI index and JOA score of the two groups were significantly improved as compared with those before the operation(P < 0. 05). Ninety-two point five percent of single-segment patients and 90.5% of double segment patients returned to normal scoliosis within 12 months after the operation. The operation time, number of intraoperative fluoroscopy times and the amount of intraoperative blood loss in single-segment patients were better than those in double-segment group(P < 0. 05). At the last follow-up, the AVT, CBD and SVA in the double-segment group were 5.2 ± 2.3, 5.1 ± 1.0 and 12.2 ± 3.0 mm, respectively, which were higher than those in the single-segment group (1.9 ± 0.4, 1.1 ± 1.6 and 3.9 ± 2.1 mm) (P < 0. 05). CONCLUSION: PELD is an effective treatment for single-segment and double-segment lumbar disc herniation with Sciatic scoliosis. Double-segment patients can enjoy similar clinical efficacy to single-segment patients, avoiding complications caused by decompression, fusion, and internal fixation. Scoliosis was corrected spontaneously within 12 months after operation, and the sagittal curve was significantly improved in both groups. The improvement of coronal and sagittal balance in double -segment patients may take longer.

An ACE2 decamer viral trap as a durable intervention solution for current and future SARS-CoV.

The capacity of SARS-CoV-2 to evolve poses challenges to conventional prevention and treatment options such as vaccination and monoclonal antibodies, as they rely on viral receptor binding domain (RBD) sequences from previous strains. Additionally, animal CoVs, especially those of the SARS family, are now appreciated as a constant pandemic threat. We present here a new antiviral approach featuring inhalation delivery of a recombinant viral trap composed of ten copies of angiotensin-converting enzyme 2 (ACE2) fused to the IgM Fc. This ACE2 decamer viral trap is designed to inhibit SARS-CoV-2 entry function, regardless of viral RBD sequence variations as shown by its high neutralization potency against all known SARS-CoV-2 variants, including Omicron BQ.1, BQ.1.1, XBB.1 and XBB.1.5. In addition, it demonstrates potency against SARS-CoV-1, human NL63, as well as bat and pangolin CoVs. The multivalent trap is effective in both prophylactic and therapeutic settings since a single intranasal dosing confers protection in human ACE2 transgenic mice against viral challenges. Lastly, this molecule is stable at ambient temperature for more than twelve weeks and can sustain physical stress from aerosolization. These results demonstrate the potential of a decameric ACE2 viral trap as an inhalation solution for ACE2-dependent coronaviruses of current and future pandemic concerns.

The plant immune receptor SNC1 monitors helper NLRs targeted by a bacterial effector.

Plants deploy intracellular receptors to counteract pathogen effectors that suppress cell-surface-receptor-mediated immunity. To what extent pathogens manipulate intracellular receptor-mediated immunity, and how plants tackle such manipulation, remains unknown. Arabidopsis thaliana encodes three similar ADR1 class helper nucleotide-binding domain leucine-rich repeat receptors (ADR1, ADR1-L1, and ADR1-L2), which are crucial in plant immunity initiated by intracellular receptors. Here, we report that Pseudomonas syringae effector AvrPtoB suppresses ADR1-L1- and ADR1-L2-mediated cell death. ADR1, however, evades such suppression by diversifying into two ubiquitination sites targeted by AvrPtoB. The intracellular sensor SNC1 interacts with and guards the CCR domains of ADR1-L1/L2. Removal of ADR1-L1/L2 or delivery of AvrPtoB activates SNC1, which then signals through ADR1 to trigger immunity. Our work elucidates the long-sought-after function of SNC1 in defense, and also how plants can use dual strategies, sequence diversification, and a multi-layered guard-guardee system, to counteract pathogen's attack on core immunity functions.

How Do the Morphological Abnormalities of Femoral Head and Neck, Femoral Shaft and Femoral Condyle Affect the Occurrence and Development of Medial Knee Osteoarthritis.

OBJECTIVE: At present, the main viewpoint is that tibial varus is the main reason of medial knee osteoarthritis (OA), and high tibial osteotomy (HTO) is also the main alignment correction method to correct medial knee OA. In contrast, the impact of the anatomical alignment of the femur on medial knee OA is often overlooked. We evaluated the increased risk for medial knee OA because a varus alignment could be attributed to the anatomical reasons that include hip anatomy, femoral shaft bowing (FSB) and femoral condylar dysplasia. METHODS: The present research adopted a cross-sectional study method. We selected 62 patients with HTO in the Third Hospital of Hebei Medical University from June 2021 to March 2022 as the HTO group and 55 healthy volunteers as the control group. Femoral neck-shaft angle (NSA), lateral FSB, mechanical lateral distal femoral angle (mLDFA) and hip-knee-ankle (HKA) was radiographically examined within the two groups. The femoral neck length and offset were also measured, and the ratio is represented by the ratio of the femoral neck length to off-set (N/O). The 2-tailed Student t-test was used to compare the differences between groups when the data were in accordance with a normal distribution. Otherwise, the Mann-Whitney U tests was used to compare the differences between groups. RESULT: Compared to the control group, the HTO group had a higher offset (p < 0.05), greater femoral neck length (p < 0.05), and decreased (more varus) NSA (p < 0.05). The HKA in the HTO group was 172.20 ° (3.50°), which was significantly lower than that of the control group 177.00° (3.05°), (p < 0.001), while the medial OA was associated with more varus HKA. The mean mLDFA was 89.10 ° (2.35°) and 87.50° (2.85°) in the HTO and control groups (p < 0.005), respectively. The mean lateral FSB values of the full-length radiographs were larger (p < 0.001) in the HTO group (4.24° ± 3.25°) than that in control group (1.16° ± 2.32°). CONCLUSION: The reduction of NSA (coxa vara) and the increase of the mLDFA can lead to medial knee OA, while the lateral FSB also affects medial OA. We believe that femoral deformity is also one of the cause of the medial knee OA. Therefore, it is necessary to evaluate the joint deformity of the femur and tibia before surgery in order to determine whether to use HTO alone to correct the lower limb alignment.

Anatomical and imaging measurements of the angle between the axis of the lumbar pedicle and lateral isthmus margin and its clinical significance.

BACKGROUND: This study aims to explore the measurement of the angle between the axis of the pedicle and the lateral margin of the isthmus on the lumbar spine, and investigate its clinical significance. METHODS: The angle was measured on 120 normal adults' X-ray and 25 dry anatomical specimens. 60 screws were placed by junior residents on 6 wet specimens through the freehand technique. 30 screws were placed on one side with their original experience. After learning the techniques mentioned in the study, 30 screws were placed on the other side. The specimens were examined by X-ray and CT, and the angles of the screw paths and the integrity of the pedicle were evaluated. RESULTS: The angles of 120 subjects and 25 anatomical specimens show a gradually increasing trend. The differences among each segment were statistically significant (P < 0.05), but the difference in the same segment between the X-ray and the anatomical specimens was not statistically significant (P > 0.05). Furthermore, the differences in L1, L2, and L3 between the two genders were not statistically significant (P > 0.05). However, the angles were larger in female group than in male group in L4 and L5, and the differences were statistically significant (P < 0.05). The difference in the deviation rate of screw placement before and after the learning was statistically significant only in the L5 segment (P < 0.05). The difference in overall excellence rate was statistically significant (P < 0.05). CONCLUSIONS: The measurement of the angle between the axis of the pedicle and the lateral margin of the isthmus on the lumbar can improve the accuracy of the lumbar sagittal screw angle.

Derotational distal femur osteotomy combined with medial patellofemoral ligament reconstruction yields satisfactory results in recurrent patellar dislocation with excessive femoral anteversion angle and trochlear dysplasia.

PURPOSE: The purpose of this study was to evaluate the clinical outcomes of medial patellofemoral ligament (MPFL) reconstruction combined with derotational distal femur osteotomy in patients with recurrent patellar dislocation who had excessive femoral anteversion angle and trochlear dysplasia. METHODS: Between 2015 and 2020, 64 patients (64 knees) with recurrent patellar dislocation, who had excessive femoral anteversion angle (≥ 25°) and trochlear dysplasia and were surgically treated using derotational distal femur osteotomy and MPFL reconstruction, were eligible for this retrospective study. These patients were assigned to two groups according to the grade of trochlear dysplasia. Group A (type A trochlear dysplasia, n = 33) and Group B (type B, C, D trochlear dysplasia, n = 31). Preoperative and postoperative patellar tilt angle (PTA), Caton-Deschamps index (CD-I), tibial tubercle-trochlear groove (TT-TG) distance and femoral anteversion angle were evaluated. Patient outcomes were assessed using the preoperative and postoperative International Knee Documentation Committee (IKDC) score, Kujala score, Lysholm score, Tegner score, and visual analog scale (VAS) score. RESULTS: A total of 64 patients (64 knees) were evaluated in this study, with a mean follow-up period of 28.4 ± 3.6 months. There were no cases of wound infection, osteotomy site fractures, deep venous thrombosis of the lower extremities, or re-dislocation in the two groups during the postoperative follow-up period. All patients returned to full extension and flexion. The postoperative Tegner score, Lysholm score, Kujala score, IKDC score, VAS score, PTA, CD-I, TT-TG distance, and femoral anteversion angle were significantly improved compared with the preoperative status (P < 0.05). There was no significant difference between the two groups (n.s.). CONCLUSION: MPFL reconstruction combined with derotational distal femur osteotomy showed satisfactory clinical outcomes during follow-up in patients with recurrent patellar dislocation who had excessive femoral anteversion angle and trochlear dysplasia. Even patients with high-grade trochlear dysplasia showed satisfactory results. For those patients, additional surgery is not necessary. LEVEL OF EVIDENCE: Level III.

Biomechanical evaluation of the hybrid pedicle screw-cortical bone trajectory technique in transforaminal lumbar interbody fusion to adjacent segment degeneration-finite element analysis.

BACKGROUND: Transforaminal lumbar interbody fusion is an effective surgical treatment of intervertebral disk herniation. However, its clinical efficacy for adjacent segment disk degeneration (ASDD) after hybrid bilateral pedicle screw - bilateral cortical screw (pedicle screw at L4 and cortical bone trajectory screw at L5) and hybrid bilateral cortical screw - bilateral pedicle screw (bilateral cortical screw at L4 and bilateral pedicle screw at L5) remains undiscovered. Therefore, the aim of this study is to evaluate the effect of the hybrid bilateral pedicle screw - bilateral cortical screw and hybrid bilateral cortical screw - bilateral pedicle screw on the adjacent segment via a 3-dimensional (3D) finite element (FE) analysis. METHODS: Four human cadaveric lumbar spine specimens were provided by the anatomy teaching and research department of Xinjiang Medical University. Four finite element models of L1-S1 lumbar spine segment were generated. For each of these, four lumbar transforaminal lumbar interbody fusion models at L4-L5 segment with the following instruments were created: hybrid bilateral pedicle screw - bilateral cortical screw, bilateral cortical screw - bilateral cortical screw (bilateral cortical screw at both L4 and L5 segments), bilateral pedicle screw - bilateral pedicle screw (bilateral pedicle screw at both L4 and L5 segments), and hybrid bilateral cortical screw - bilateral pedicle screw. A 400-N compressive load with 7.5 Nm moments was applied for the simulation of flexion, extension, lateral bending, and rotation. The range of motion of L3-L4 and L5-S1 segments and von Mises stress of the intervertebral disc at the adjacent segment were compared. RESULTS: Hybrid bilateral pedicle screw - bilateral cortical screw has the lowest range of motion at L3-L4 segment in flexion, extension, and lateral bending, and the highest disc stress in all motions, while the range of motion at L5-S1 segment and disc stress was lower than bilateral pedicle screw - bilateral pedicle screw in flexion, extension, and lateral bending, and higher than bilateral cortical screw - bilateral cortical screw in all motions. The range of motion of hybrid bilateral cortical screw - bilateral pedicle screw at L3-L4 segment was lower than bilateral pedicle screw - bilateral pedicle screw and higher than bilateral cortical screw - bilateral cortical screw in flexion, extension, and lateral bending, and the range of motion at L5-S1 segment was higher than bilateral pedicle screw - bilateral pedicle screw in flexion, lateral bending, and axial rotation. The disc stress at L3-L4 segment was lowest and more dispersed in all motions, and the disc stress at L5-S1 segment was higher than bilateral pedicle screw - bilateral pedicle screw in lateral bending and axial rotation, but more dispersed. CONCLUSION: Hybrid bilateral cortical screw - bilateral pedicle screw decreases the impact on adjacent segments after spinal fusion, reduces the iatrogenic injury to the paravertebral tissues, and provides throughout decompression of the lateral recess.

Complication, fusion, and revision rate in the lumbar cortical bone trajectory and pedicle screw fixation techniques: a systematic review and meta-analysis.

BACKGROUND: To obtain the complication rate, fusion rate, and revision rate of the lumbar cortical bone trajectory technique and pedicle screw fixation technique in lumbar interbody fusion surgery by single-arm meta-analysis and lay a basis for orthopedic surgeons to select the fixation techniques and perioperative management. METHODS: PubMed, Ovid Medline, Web of Science, CNKI, and Wanfang databases were searched comprehensively. Data extraction, content analysis, and quality assessment of the literature were performed by two independent reviewers according to the Cochrane Collaboration guidelines using R and STATA software for single-arm meta-analysis. RESULTS: The total complication rate of the lumbar cortical bone trajectory technique was 6%, including a hardware complication rate of 2%, ASD (adjacent segment degeneration) rate of 1%, wound infection rate of 1%, dural damage rate of 1%, hematoma rate tending to 0%, fusion rate of 94%, and revision rate of 1%. Lumbar pedicle screw fixation techniques had a total complication rate of 9%, with a hardware complication rate of 2%, ASD rate of 3%, wound infection rate of 2%, dural damage rate of 1%, hematoma rate tending to 0%, fusion rate of 94%, and revision rate of 5%. This study was registered with PROSPERO, CRD42022354550. CONCLUSION: Lumbar cortical bone trajectory was associated with a lower total complication rate, ASD rate, wound infection rate, and revision rate than pedicle screw fixation. The cortical bone trajectory technique reduces the incidence of intraoperative and postoperative complications and can be an alternative in lumbar interbody fusion surgery.

Hybrid pedicle screw and modified cortical bone trajectory technique in transforaminal lumbar interbody fusion at L4-L5 segment: finite element analysis.

BACKGROUND: Investigate the biomechanical properties of the hybrid fixation technique with bilateral pedicle screw (BPS) and bilateral modified cortical bone trajectory screw (BMCS) in L4-L5 transforaminal lumbar interbody fusion (TLIF). METHODS:  Three finite element (FE) models of the L1-S1 lumbar spine were established according to the three human cadaveric lumbar specimens. BPS-BMCS (BPS at L4 and BMCS at L5), BMCS-BPS (BMCS at L4 and BPS at L5), BPS-BPS (BPS at L4 and L5), and BMCS-BMCS (BMCS at L4 and L5) were implanted into the L4-L5 segment of each FE model. The range of motion (ROM) of the L4-L5 segment, von Mises stress of the fixation, intervertebral cage, and rod were compared under a 400-N compressive load with 7.5 Nm moments in flexion, extension, bending, and rotation. RESULTS:  BPS-BMCS technique has the lowest ROM in extension and rotation, and BMCS-BMCS technique has the lowest ROM in flexion and lateral bending. The BMCS-BMCS technique showed maximal cage stress in flexion and lateral bending, and the BPS-BPS technique in extension and rotation. Compared to the BPS-BPS and BMCS-BMCS technique, BPS-BMCS technique presented a lower risk of screw breakage and BMCS-BPS technique presented a lower risk of rod breakage. CONCLUSION:  The results of this study support that the use of the BPS-BMCS and BMCS-BPS techniques in TLIF surgery for offering the superior stability and a lower risk of cage subsidence and instrument-related complication.

Surgical Treatment for Displaced Odontoid Synchondrosis Fracture: A Retrospective Case Series Study.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Odontoid synchondrosis fracture is rare, and there is a paucity of literature on its surgical treatments. This case series study analyzed patients treated with C1 to C2 internal fixation with or without anterior atlantoaxial release and discussed the clinical effectiveness of the procedure. METHODS: Data were retrospectively collected from a single-center cohort of patients who had undergone surgical treatments for displaced odontoid synchondrosis fracture. The operation time and blood loss volume were recorded. Neurological function was assessed and classified using the Frankel grades. The odontoid process tilting angle (OPTA) was used to evaluate fracture reduction. Fusion duration and complications were also analyzed. RESULTS: Seven patients (1 boy and 6 girls) were included in the analysis. Three patients underwent anterior release and posterior fixation surgery, and the other 4 underwent posterior-only surgery. The fixation segment was C1 to C2. The average follow-up period was 34.7 ± 8.5 months. The average operation time was 145.7 ± 45.3 min, with an average blood loss volume of 95.7 ± 33.3 mL. The OPTA was corrected from 41.9° ± 11.1° preoperative to 2.4° ± 3.2° at the final follow-up (P < .05). The preoperative Frankel grade of 1 patient was grade C, of 2 patients was grade D, and of 4 patients was grade E. The neurological function of the patients in grade C and grade D recovered to grade E at the final follow-up. None of the patients developed a complication. All the patients achieved odontoid fracture healing. CONCLUSIONS: Posterior C1 to C2 internal fixation with or without anterior atlantoaxial release is a safe and effective method for treating young children with displaced odontoid synchondrosis fracture.

The MAPK-Alfin-like 7 module negatively regulates ROS scavenging genes to promote NLR-mediated immunity.

Nucleotide-binding leucine-rich repeat (NLR) receptor-mediated immunity includes rapid production of reactive oxygen species (ROS) and transcriptional reprogramming, which is controlled by transcription factors (TFs). Although some TFs have been reported to participate in NLR-mediated immune response, most TFs are transcriptional activators, and whether and how transcriptional repressors regulate NLR-mediated plant defenses remains largely unknown. Here, we show that the Alfin-like 7 (AL7) interacts with N NLR and functions as a transcriptional repressor. Knockdown and knockout of AL7 compromise N NLR-mediated resistance against tobacco mosaic virus, whereas AL7 overexpression enhances defense, indicating a positive regulatory role for AL7 in immunity. AL7 binds to the promoters of ROS scavenging genes to inhibit their transcription during immune responses. Mitogen-activated protein kinases (MAPKs), salicylic acid-induced protein kinase (SIPK), and wound-induced protein kinase (WIPK) directly interact with and phosphorylate AL7, which impairs the AL7-N interaction and enhances its DNA binding activity, which promotes ROS accumulation and enables immune activation. In addition to N, AL7 is also required for the function of other Toll interleukin 1 receptor/nucleotide-binding/leucine-rich repeats (TNLs) including Roq1 and RRS1-R/RPS4. Our findings reveal a hitherto unknown MAPK-AL7 module that negatively regulates ROS scavenging genes to promote NLR-mediated immunity.

Morphometric measurement of lumbar pedicle in different regions: a systematic review.

OBJECTIVE: To collect the data of pedicle width and height in different areas, and to investigate the difference and variation rule of pedicle width and height. METHODS: Comprehensive search of PubMed, Ovid Medline, and Web of science databases was performed. Collected data were imported into SPSS, and one-way ANOVA test and post hoc test were used to determine whether there were statistical differences in pedicle width and height between the different regions. RESULTS: Oceania had the largest pedicle width and height, followed by Americans. West Asian had the largest pedicle width in Asia, followed by East and Southeast Asian, and Chinese and South Asian had similar pedicle width. Different from the variation pattern of pedicle width, the pedicle height of Chinese, East and Southeast Asian and West Asian in Asian range is similar, but the pedicle height of South Asian is significantly smaller than the first three, and has statistical significance. CONCLUSIONS: People in different regions have similar patterns of variation in pedicle width and height even though they belong to different ethnic groups. This phenomenon is particularly prominent and pronounced in populations in geographically close areas, which may be related to inter-ethnic integration due to population movement between adjacent areas. There is a relationship between the morphological characteristics of the human lumbar pedicle and geographical location.

One-stage posterior surgery combined with anti-Brucella therapy in the management of lumbosacral brucellosis spondylitis: a retrospective study.

BACKGROUND: This study aimed to assess the clinical efficacy of one-stage posterior surgery combined with anti-Brucella therapy in the treatment of lumbosacral brucellosis spondylitis (LBS). METHODS: From June 2010 to June 2020, the clinical and radiographic data of patients with LBS treated by one-stage posterior surgery combined with anti-Brucella therapy were retrospectively analyzed. The visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) and Oswestry Disability Index scores (ODI) were used to evaluate the clinical outcomes. Frankel's classification system was employed to access the initial and final neurologic function. Fusion of the bone grafting was classified by Bridwell's grading system. RESULTS: A total of 55 patients were included in this study with a mean postoperative follow-up time of 2.6 ± 0.8 years (range, 2 to 5). There were 40 males and 15 females with a mean age of 39.8 ± 14.7 years (range, 27 to 57). The Brucella agglutination test was ≥ 1:160 in all patients, but the blood culture was positive in 43 patients (78.1%). A statistical difference was observed in ESR, CRP, VAS, ODI, and JOA between preoperative and final follow-up (P < 0.05). Neurological function was significantly improved in 20 patients with preoperative neurological dysfunction after surgery. According to Bridwell's grading system, the fusion of bone grafting in 48 cases (87.2%) was defined as grade I, and grade II in 7 cases (12.7%). None of the infestation recurrences was observed. CONCLUSION: One-stage posterior surgery combined with anti-Brucella therapy was a practical method in the treatment of LBS with severe neurological compression and spinal sagittal imbalance.

Feasibility and improvement of a three-dimensional printed navigation template for modified cortical bone trajectory screw placement in the lumbar spine.

Objectives: Compared with traditional pedicle screw trajectory, cortical bone trajectory (CBT) increases the contact surface between the screw and cortical bone where the screw is surrounded by dense cortical bone, which does not deform remarkably due to degeneration. We aimed to provide detailed information about the improvement of three-dimensional (3D)-printed navigation templates for modified CBT screw placement in the lumbar spine and evaluate the safety and accuracy thereof. Methods: Four human cadaveric lumbar spine specimens were selected. After CT scanning data were reconstructed to 3D models, either the left or right side of each specimen was randomly selected to establish a 3D-navigation template, mutually complemented with the surface anatomical structure of the lateral margin of the lumbar isthmus, vertebral plate, and spinous process. The corresponding 3D centrum was printed according to the CT scanning data, and a navigation template of supporting design was made according to modified cortical bone technique. The same template was used to insert CBT screws into 3D printed and cadaveric specimens. After the screws were inserted, the screw path of the 3D printed specimens was directly observed, and that of the anatomical specimens was scanned by CT, to determine the position and direction of the screws to analyze the success rate of screw placement. Results: Twenty cortical bone screws were placed in each of the 3D printed and anatomical specimens, with excellent rates of screw placement of 100% and 95%, respectively. Conclusions: We report the easy, safe, accurate, and reliable use of a 3D-printed navigation template to carry out screw placement by modified cortical bone technique in the lumbar spine.