A Novel Multiepitope Fusion Antigen as a Vaccine Candidate for the Prevention of Enterotoxigenic E. coli-Induced Calf Diarrhea.

Calf diarrhea caused by enterotoxigenic E. coli (ETEC) poses an enormous economic challenge in the cattle industry. Fimbriae and enterotoxin are crucial virulence factors and vaccine targets of ETEC. Since these proteins have complicated components with large molecular masses, the development of vaccines by directly expressing these potential targets is cumbersome Therefore, this study aimed to develop a multiepitope fusion antigen designated as MEFA by integrating major epitopes of FanC and Fim41a subunits and a toxoid epitope of STa into the F17G framework. The 3D modeling predicted that the MEFA protein displayed the epitopes from these four antigens on its surface, demonstrating the desired structural characteristics. Then, the MEFA protein was subsequently expressed and purified for mouse immunization. Following that, our homemade ELISA showed that the mouse antiserum had a consistent increase in polyclonal antibody levels with the highest titer of 1:217 to MEFA. Furthermore, the western blot assay demonstrated that this anti-MEFA serum could react with all four antigens. Further, this antiserum exhibited inhibition on ETEC adhesion to HCT-8 cells with inhibitory rates of 92.8%, 84.3%, and 87.9% against F17+, F5+, and F41+ ETEC strains, respectively. Additionally, the stimulatory effect of STa toxin on HCT-8 cells was decreased by approximately 75.3% by anti-MEFA serum. This study demonstrates that the MEFA protein would be an antigen candidate for novel subunit vaccines for preventing ETEC-induced diarrhea in cattle.

Sclerosis rim volume ratio and Japanese Investigation Committee classification as predictive factors for femoral head collapse progression after non-vascularized fibular grafting in osteonecrosis patients.

OBJECTIVE: The purpose of this retrospective cohort study was to determine the relationship between sclerosis rim volume ratio (SVR) and the progression of femoral head collapse after non-vascularized fibular grafting (NVFG) surgery in patients with osteonecrosis of the femoral head (ONFH), investigating risk factors associated with femoral head collapse progression and establishing a predictive model to enhance clinical decision-making. METHODS: ONFH patients who underwent NVFG between January 2008 and December 2021 were analyzed retrospectively to assess the risk of post-operative collapse progression (collapse >2 mm). A logistic regression model was used to evaluate the independent risk factors associated with collapse progression, including age, sex, etiology, affected side, Japanese Investigation Committee classification (JIC), and the sclerosis rim volume ratio (SVR). SVR values was collected from three weight-bearing columns, namely SVR1, SVR2, and SVR3, respectively. RESULTS: 57 patients with 64 hips who had undergone NVFG and were followed up for at least one year were included. During the follow-up, collapse＞2 mm occurred in 30 hips (46.88%). Multivariable analysis revealed that JIC (p =0.037) and SVR1 (p = 0.04) were independent risk factors for collapse progression after NVFG. The results of the receiver operating characteristic (ROC) analysis indicated that the aforementioned indices provided a satisfactory prediction of early femoral head collapse progression in ONFH patients after NVFG. The regression model using the above two indicators as a composite index showed satisfactory performance in predicting early postoperative femoral head collapse progression, with an area under the curve (AUC) of 84.6%. CONCLUSIONS: SVR is significant predictor of post-operative collapse progression following NVFG, and the composite index provides an optimal predictive value for femoral head collapse progression after surgery.

Does robot-assisted percutaneous hollow screw placement combined with tarsal sinus incision reduction in the treatment of calcaneal fracture perform better at a minimum two year follow-up compared with traditional surgical reduction and fixation?

PURPOSE: We aimed to evaluate the safety and efficacy of robot-assisted percutaneous hollow screw placement combined with tarsal sinus incisions for treating calcaneal fractures. METHODS: Clinical data of 50 patients with calcaneal fractures treated from January 2018 to June 2020 were analyzed retrospectively. Twenty-six patients (26 feet) were included in the traditional group (traditional surgical reduction and internal fixation) and 24 (24 feet) in the robot-assisted group (robot-assisted internal fixation of tarsal sinus incision). The operation time, C-arm fluoroscopy dose, fracture healing time, Gissane angle, Böhler angle, calcaneal width, calcaneal height, visual analogue scale (VAS) scores, and American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores were compared between the groups preoperatively and two years postoperatively. RESULTS: Operation time was significantly longer in the traditional group than in the robot-assisted group, while the intraoperative C-arm fluoroscopy dose was significantly lower in the robot-assisted than in the traditional group (P < 0.05). Both groups were followed up for 24-26 months (average, 24.9 months). Two years postoperatively, the Gissane angle, Böhler angle, calcaneal height, and calcaneal width improved significantly in both groups, without significant differences. Fracture healing time was not significantly different in both groups (P > 0.05). The two year postoperative VAS and AOFAS scores in both groups were significantly higher than the preoperative scores, but the robot-assisted group postoperative AOFAS scores were significantly higher than those in the traditional group (t = - 3.775, P = 0.000). CONCLUSION: Robot-assisted internal fixation of tarsal sinus incision is effective in treating calcaneal fractures with satisfactory long-term follow-up outcomes.

High-Resolution 3D Genome Map of Brucella Chromosomes in Exponential and Stationary Phases.

The three-dimensional (3D) genome structure of an organism or cell is highly relevant to its biological activities, but the availability of 3D genome information for bacteria, especially intracellular pathogens, is still limited. Here, we used Hi-C (high-throughput chromosome conformation capture) technology to determine the 3D chromosome structures of exponential- and stationary-phase Brucella melitensis at a 1-kb resolution. We observed that the contact heat maps of the two B. melitensis chromosomes contain a prominent diagonal and a secondary diagonal. Then, 79 chromatin interaction domains (CIDs) were detected at an optical density at 600 nm (OD600) of 0.4 (exponential phase), with the longest CID being 106 kb and the shortest being 12 kb. Moreover, we obtained 49,363 significant cis-interaction loci and 59,953 significant trans-interaction loci. Meanwhile, 82 CIDs of B. melitensis at an OD600 of 1.5 (stationary phase) were detected, with the longest CID being 94 kb and the shortest being 16 kb. In addition, 25,965 significant cis-interaction loci and 35,938 significant trans-interaction loci were obtained in this phase. Furthermore, we found that as the B. melitensis cells grew from the logarithmic to the plateau phase, the frequency of short-range interactions increased, while that of long-range interactions decreased. Finally, combined analysis of 3D genome and whole-genome transcriptome (RNA-seq) data revealed that the strength of short-range interactions in Chr1 is specifically and strongly correlated with gene expression. Overall, our study provides a global view of the chromatin interactions in the B. melitensis chromosomes, which will serve as a resource for further study of the spatial regulation of gene expression in Brucella. IMPORTANCE The spatial structure of chromatin plays important roles in normal cell functions and in the regulation of gene expression. Three-dimensional genome sequencing has been performed in many mammals and plants, but the availability of such data for bacteria, especially intracellular pathogens, is still limited. Approximately 10% of sequenced bacterial genomes contain more than one replicon. However, how multiple replicons are organized within bacterial cells, how they interact, and whether these interactions help to maintain or segregate these multipartite genomes are unresolved issues. Brucella is a Gram-negative, facultative intracellular, and zoonotic bacterium. Except for Brucella suis biovar 3, Brucella species have two chromosomes. Here, we applied Hi-C technology to determine the 3D genome structures of exponential- and stationary-phase Brucella melitensis chromosomes at a 1-kb resolution. Combined analysis of the 3D genome and RNA-seq data indicated that the strength of short-range interactions in B. melitensis Chr1 is specifically and strongly correlated with gene expression. Our study provides a resource to achieve a deeper understanding of the spatial regulation of gene expression in Brucella.

TiRobot-assisted percutaneous kyphoplasty in the management of multilevel (more than three levels) osteoporotic vertebral compression fracture.

PURPOSE: To compare the effectiveness of TiRobot-assisted kyphoplasty with that of the traditional fluoroscopy-assisted approach in treating multilevel osteoporotic vertebral compression fractures. METHODS: In this retrospective study, we collected data from 71 patients (TiRobot-assisted group, n = 39; fluoroscopy-assisted group, n = 32) with multilevel osteoporotic vertebral compression fracture treated with unilateral traditional TiRobot-assisted or fluoroscopy-assisted percutaneous kyphoplasty. The operative time, infusion volume, length of stay (LOS), hospital expenses, visual analog scale (VAS), Oswestry Disability Index (ODI), radiation exposure, puncture deviation, anterior height of diseased vertebrae, local kyphotic angle, bone cement distribution, and bone cement leakage were compared between the TiRobot- and fluoroscopy-assisted groups. RESULTS: Of the 257 treated vertebrae, the average amount of bone cement injected in the TiRobot-assisted (142 vertebrae) and fluoroscopy-assisted (115 vertebrae) groups was 4.6 mL and 4.5 mL, respectively. The VAS score was significantly lower in the TiRobot-assisted group at 24 hours post-operatively (p = 0.006). The X-ray frequency was 34.7 times in the TiRobot-assisted group and 51.7 times in the fluoroscopy-assisted group (p < 0.001). In addition to the operative time, cumulative radiation dose for the surgeon and patient was significantly lower in the TiRobot-assisted group. The hospital expenses of the TiRobot-assisted group were significantly higher (p < 0.001). The puncture deviation and bone cement distribution were better in the TiRobot-assisted group (p < 0.001). Bone cement leakage was found in 18 and 29 cases in the TiRobot- and fluoroscopy-assisted groups, respectively (p = 0.010). One patient in the fluoroscopy-assisted group experienced radiculopathy due to a misplaced puncture but recovered in three months. No radiculopathy was observed in the TiRobot-assisted group. CONCLUSIONS: TiRobot-assisted percutaneous multilevel kyphoplasty is more accurate and has smaller radiometry, a more uniform bone cement distribution, and lower bone cement leakage. This method was therefore accurate and safe.

Entrapment of a metal foreign body in the heart during surgical procedure: A case report and literature review.

A rongeur had been used to remove thin bones in both orthopedic surgery and neurosurgery, featured with a tip holding and cutting bone effectively while protecting the underlying instruments. The authors describe a case of a 40-year-old man who proceeded with the second lumbar vertebrae osteotomy and presented to be ankylosing spondylitis with kyphosis and limited mobility for 10 years. During the surgery, we found that the rongeur tip was missing. C-arm fluoroscopy showed the high-density body just in front of the vertebral body intraoperatively. However, the CT scan showed the foreign body migrated to the right auricle of the heart postoperatively. This case is unique in that there was no exact vessel injury detected intraoperatively. There were few reports about the surgical instrument migrating to the heart. Our case showed the rare experience of the function of multidisciplinary collaboration in the migration of foreign bodies in the cervical spinal canal.

[Comparison of short-term effectiveness of metal screws and absorbable screws in repair of distal tibiofibular syndesmosis].

Objective: To compare the short-term effectiveness of repairing distal tibiofibular syndesmosis with metal screws and absorbable screws. Methods: A retrospective analysis was performed on the clinical data of 63 patients with ankle fracture combined with injury of the distal tibiofibular syndesmosis admitted between January 2017 and January 2020. Among them, 31 patients were treated with absorbable screw fixation of the distal tibiofibular syndesmosis (research group) and 32 patients were treated with metal screw fixation of the distal tibiofibular syndesmosis (control group). There was no significant difference in gender, age, cause of injury, surgical side, time from injury to operation, fracture type, preoperative visual analogue scale (VAS) score, and American Orthopaedic Foot & Ankle Society (AOFAS) score between the two groups ( P>0.05). The operation time and fracture healing time were recorded and compared between the two groups. X-ray film was taken to evaluate the effect of ankle joint reduction and fixation. Olerud-Molander ankle fracture efficacy score (short for OM score), AOFAS score, and VAS score were used to evaluate the effectiveness. Results: There was no significant difference in operation time between the two groups ( t=-0.683, P=0.497). In the control group, 1 case of delayed healing and 1 case of poor healing occurred in the lateral incision after operation, which healed after dressing change; the rest of the patients had primary healing of the incision. Patients in both groups were followed up 12-24 months, with an average of 13.8 months. In the control group, 1 patient with fracture of pronation and external rotation walked with full weight bearing after removing the metal screw of the distal tibiofibular syndesmosis at 8 weeks after operation, the anatomical plate of the lateral malleolus was broken, and the lateral malleolus was fixed again and recovered after 5 months; 1 patient had mild ankle pain after operation, and the pain disappeared after removing the metal screw of the distal tibiofibular syndesmosis at 8 weeks. No complication such as nerve and blood vessel injury occurred in all patients. There was no significant difference in fracture healing time between the two groups ( t=-1.128, P=0.264). The AOFAS and VAS scores significantly improved in both groups at 12 months after operation ( P<0.05). There was no significant difference between the two groups in the OM scores, and the difference of AOFAS and VAS scores between before and after operation ( P>0.05). Conclusion: Using absorbable screws to repair the distal tibiofibular syndesmosis can effectively restore the ankle acupoint structure, prevent ankle instability, and restore good ankle function. There is no significant difference in effectiveness between absorbable screws and metal screws, and there is no need for secondary operation to remove screws.

Efficacy of vertebral augmentation in the treatment of osteoporotic vertebral compression fractures: a systematic review and meta-analysis.

BACKGROUND: Percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) are common vertebral augmentation (VA) procedures for the treatment of osteoporotic vertebral compression fractures (OVCF), each with their own advantages and disadvantages. In recent years, the development of new implant-assisted technologies has provided a breakthrough in VA. This study systematically evaluated and meta-analyzed the reports on new implant-assisted VA techniques in recent years, so as to provide evidence for clinical diagnosis and treatment. METHODS: The PubMed, Embase, Ovid, and SpringerLink databases were searched for randomized controlled studies on VA in the treatment of OVCF. In this study, patients in the experimental group were treated with PVP using the new implant-assisted VA technique, while patients in the control group were treated with PKP. Bias assessment was conducted using the tool integrated with the Revman 5.4 software, and meta-analysis was carried out to compare the mid-term postoperative pain relief, functional status, quality of life, and cement extravasation between the two groups (each presented with a forest plot). RESULTS: Eight articles were finally included in the selection, involving a total of 1,027 patients. PVP surgery using the new implant-assisted VA technique was superior to PKP surgery in relieving postoperative pain [mean difference (MD) =-3.77, 95% CI: -5.63, -1.92, P<0.0001] and improving the postoperative Oswestry Disability Index (ODI) score (MD =-1.59, 95% CI: -3.01, -0.16, P=0.03). However, it was not significantly different from PKP surgery in improving postoperative quality of life (MD =-0.27, 95% CI: -3.55, 3.01, P=0.87), and the cement extravasation rate was significantly lower than that of PKP surgery [odd ratio (OR) =0.38, 95% CI: 0.19, 0.74, P=0.004]. DISCUSSION: The new implant-assisted VA technique can significantly relieve pain, reduce clinical symptoms, improve postoperative quality of life, and significantly reduce the problem of cement extravasation. However, this new technology is still evolving, and more high-quality randomized controlled studies on this topic are needed to provide stronger evidence.

[Effect of prophylactic C 4, 5 foraminal dilatation in posterior cervical open-door surgery on postoperative C 5 nerve root palsy syndrome].

OBJECTIVE: To investigate the effect of prophylactic C 4, 5 foraminal dilatation in posterior cervical open-door surgery on postoperative C 5 nerve root palsy syndrome. METHODS: The clinical data of patients with cervical spondylotic myelopathy (cervical spinal cord compression segments were more than 3) who met the selection criteria between March 2016 and March 2019 were retrospectively analyzed. Among them, 40 patients underwent prophylactic C 4, 5 foraminal dilatation in posterior cervical open-door surgery (observation group) and 40 patients underwent simple posterior cervical open-door surgery (control group). There was no significant difference between the two groups ( P>0.05) in gender, age, disease duration, Nurick grade of spinal cord symptoms, and preoperative diameter of C 4, 5 intervertebral foramen, Japanese Orthopaedic Association (JOA) score, and visual analogue scale (VAS) score. The occurrence of C 5 nerve root paralysis syndrome was recorded and compared between the two groups, including incidence, paralysis time, recovery time, and spinal cord drift. VAS and JOA scores were used to evaluate the improvement of pain and function before operation and at 12 months after operation. RESULTS: The incisions of the two groups healed by first intention, and there was no early postoperative complications such as cerebrospinal fluid leakage. Patients of both groups were followed up 12-23 months, with an average of 17.97 months. C 5 nerve root paralysis syndrome occurred in 8 cases in the observation group (3 cases on the right and 5 cases on the left) and 2 cases in the control group (both on the right). There was significant difference of the incidence (20% vs. 5%) between the two groups ( χ 2=4.114, P=0.043). Except for 1 case in the observation group who developed C 5 nerve root palsy syndrome at 5 days after operation, the rest patients all developed at 1 day after operation; the recovery time of the observation group and the control group were (3.87±2.85) months and (2.50±0.70) months respectively, showing no significant difference between the two groups ( t=-0.649, P=0.104). At 12 months after operation, the JOA score and VAS score of cervical spine in the two groups significantly improved when compared with those before operation ( P<0.05); there was no significant difference in the difference of the cervical spine JOA score and VAS score between at 12 months after operation and before operation and the degree of spinal cord drift between the two groups ( P>0.05). CONCLUSION: Prophylactic C 4, 5 foraminal dilatation can not effectively prevent and reduce the occurrence of postoperative C 5 root palsy, on the contrary, it may increase its incidence, so the clinical application of this procedure requires caution.

Path Planning for Mobile Robot Based on Improved Bat Algorithm.

Bat algorithm has disadvantages of slow convergence rate, low convergence precision and weak stability. In this paper, we designed an improved bat algorithm with a logarithmic decreasing strategy and Cauchy disturbance. In order to meet the requirements of global optimal and dynamic obstacle avoidance in path planning for a mobile robot, we combined bat algorithm (BA) and dynamic window approach (DWA). An undirected weighted graph is constructed by setting virtual points, which provide path switch strategies for the robot. The simulation results show that the improved bat algorithm is better than the particle swarm optimization algorithm (PSO) and basic bat algorithm in terms of the optimal solution. Hybrid path planning methods can significantly reduce the path length compared with the dynamic window approach. Path switch strategy is proved effective in our simulations.

[A comparative study on internal fixation of calcaneal fractures assisted by robot and traditional open reduction internal fixation].

OBJECTIVE: To compare the effectiveness of robot assisted internal fixation and traditional open reduction and internal fixation for calcaneal fractures. METHODS: The clinical data of 44 patients (44 feets) with calcaneal fracture admitted between October 2017 and December 2018 who met the selection criteria were retrospectively analyzed. According to different operation methods, they were divided into trial group (19 cases, treated with robot assisted percutaneous reduction and cannulated screw fixation through tarsal sinus incision) and control group (25 cases, treated with open reduction and internal fixation via traditional tarsal sinus incision). There was no significant difference in gender, age, injured side, cause of injury, fracture type, time from injury to operation, and preoperative Böhler angle, Gissane angle, calcaneus width, American Orthopedic Foot and Ankle Association (AOFAS) score, and other general data between the two groups ( P>0.05). The operation time, intraoperative fluoroscopy frequency, and fracture healing time were recorded and compared between the two groups. Before operation and at 6 months after operation, the Böhler angle and Gissane angle were measured on the lateral X-ray film, and the calcaneal width was measured on the axial X-ray film of the calcaneus to evaluate the recovery of the deformity and collapse after surgical treatment; the AOFAS score was used to evaluate the function of the affected foot and ankle joint. RESULTS: The operation time of the trial group was significantly longer than that of the control group ( P<0.05), but the intraoperative fluoroscopy frequency was significantly less than that of the control group ( P<0.05). In the control group, 1 case had skin necrosis, and 1 case had a little leakage from the incision; the rest of the two groups had no skin- and incision-related complications. Patients in both groups were followed up 6-12 months, with an average of 9.5 months. At 6 months after operation, the Böhler angle, Gissane angle, and calcaneal width in the two groups were significantly improved when compared with preoperative ones ( P<0.05), and there was no significant difference between the two groups ( P>0.05); the fractures in the two groups were healed, there was no significant difference in healing time ( t=-1.890, P=0.066); the AOFAS scores of the two groups were significantly higher than those before operation ( P<0.05), and the AOFAS score of the trial group was significantly higher than that of the control group ( t=-3.135, P=0.003). CONCLUSION: Compared with traditional C-arm fluoroscopic internal fixation for calcaneal fractures, robot-assisted internal fixation via tarsal sinus incision for calcaneal fractures significantly improves the function of the affected foot and maintains the accuracy of nail implantation after fracture reduction, reducing intraoperative fluoroscopy times, and the fracture heals well.

A Case Report of Complete Dislocation of Atlantoaxial Joint due to a Traumatic and Pathological Axial Lesion.

BACKGROUND: Atlantoaxial dislocation usually results in sudden death. The patient had never found any axial lesion before, and the atlantoaxial joint dislocation was caused by rotation of the neck due to discomfort of the neck. The patient was given surgical treatment after the rescue of respiratory and cardiac arrest during transportation, which was extremely rare and rarely reported. METHODS: A 62-year-old male patient presented with limited cervical mobility after a violent rotation of the neck due to neck discomfort. X-ray and computed tomography (CT) scan suggested atlantoaxial dislocation. Sudden respiratory and cardiac arrest during transportation was immediately followed by continuous cranial traction and successful occipital and neck fusion operation. RESULTS: After the successful rescue of endotracheal intubation, the patient was given continuous cranial traction. After the completion of CT scan, the patient was given occipital neck fusion, and 6 days after the surgery, the patient wore the skull-neck-thorax brace and walked freely. CONCLUSION: Continuous cranial traction and posterior occipitocervical fusion are effective methods for treating axial pathological fracture with atlantoaxial dislocation. LEVEL OF EVIDENCE: 5.