[Effectiveness of reduction robot combined with navigation robot-assisted minimally invasive treatment for Tile type B pelvic fractures].

Objective: To explore the effectiveness of reduction robot combined with navigation robot-assisted minimally invasive treatment for Tile type B pelvic fractures. Methods: Between January 2022 and February 2023, 10 patients with Tile type B pelvic fractures were admitted. There were 6 males and 4 females with an average age of 45.5 years (range, 30-71 years). The fractures were caused by traffic accident in 5 cases, bruising by heavy object in 3 cases, and falling from height in 2 cases. The interval between injury and operation ranged from 4-13 days (mean, 6.8 days). There were 2 cases of Tile type B1 fractures, 1 case of Tile type B2 fracture, and 7 cases of Tile type B3 fractures. After closed reduction under assistance of reduction robot, the anterior ring was fixed with percutaneous screws with or without internal fixator, and the posterior ring was fixed with sacroiliac joint screws under assistance of navigation robot. The time of fracture reduction assisted by the reduction robot was recorded and the quality of fracture reduction was evaluated according to the Matta scoring criteria. The operation time, intraoperative fluoroscopy frequency and time, intraoperative bleeding volume, and incidence of complications were also recorded. During follow-up, the X-ray film of pelvis was taken to review the fracture healing, and the Majeed score was used to evaluate hip joint function. Results: The time of fracture reduction was 42-62 minutes (mean, 52.3 minutes). The quality of fracture reduction according to the Matta scoring criteria was rated as excellent in 4 cases, good in 5 cases, and poor in 1 case, with excellent and good rate of 90%. The operation time was 180-235 minutes (mean, 215.5 minutes). Intraoperative fluoroscopy was performed 18-66 times (mean, 31.8 times). Intraoperative fluoroscopy time was 16-59 seconds (mean, 28.6 seconds). The intraoperative bleeding volume was 50-200 mL (range, 110.0 mL). No significant vascular or nerve injury occurred during operation. All patients were followed up 13-18 months (mean, 16 months). X-ray films showed that all fractures healed with the healing time of 11-14 weeks (mean, 12.3 weeks). One case of ectopic ossification occurred during follow-up. At last follow-up, the Majeed score was 70-92 (mean, 72.7), and the hip joint function was rated as excellent in 2 cases and good in 8 cases, with the excellent and good rate of 100%. Conclusion: The reduction robot combined with navigation robot-assisted minimally invasive treatment for Tile type B pelvic fractures has the characteristics of intelligence, high safety, convenient operation, and minimally invasive treatment, which can achieve reliable effectiveness.

Elucidation and Pharmacologic Targeting of Master Regulator Dependencies in Coexisting Diffuse Midline Glioma Subpopulations.

Diffuse Midline Gliomas (DMGs) are universally fatal, primarily pediatric malignancies affecting the midline structures of the central nervous system. Despite decades of clinical trials, treatment remains limited to palliative radiation therapy. A major challenge is the coexistence of molecularly distinct malignant cell states with potentially orthogonal drug sensitivities. To address this challenge, we leveraged established network-based methodologies to elucidate Master Regulator (MR) proteins representing mechanistic, non-oncogene dependencies of seven coexisting subpopulations identified by single-cell analysis-whose enrichment in essential genes was validated by pooled CRISPR/Cas9 screens. Perturbational profiles of 372 clinically relevant drugs helped identify those able to invert the activity of subpopulation-specific MRs for follow-up in vivo validation. While individual drugs predicted to target individual subpopulations-including avapritinib, larotrectinib, and ruxolitinib-produced only modest tumor growth reduction in orthotopic models, systemic co-administration induced significant survival extension, making this approach a valuable contribution to the rational design of combination therapy.

Effects of depth of straw returning on maize yield potential and greenhouse gas emissions.

Appropriate straw incorporation has ample agronomic and environmental benefits, but most studies are limited to straw mulching or application on the soil surface. To determine the effect of depth of straw incorporation on the crop yield, soil organic carbon (SOC), total nitrogen (TN) and greenhouse gas emission, a total of 4 treatments were set up in this study, which comprised no straw returning (CK), straw returning at 15 cm (S15), straw returning at 25 cm (S25) and straw returning at 40 cm (S40). The results showed that straw incorporation significantly increased SOC, TN and C:N ratio. Compared with CK treatments, substantial increases in the grain yield (by 4.17~5.49% for S15 and 6.64~10.06% for S25) were observed under S15 and S25 treatments. S15 and S25 could significantly improve the carbon and nitrogen status of the 0-40 cm soil layer, thereby increased maize yield. The results showed that the maize yield was closely related to the soil carbon and nitrogen index of the 0-40 cm soil layer. In order to further evaluate the environmental benefits of straw returning, this study measured the global warming potential (GWP) and greenhouse gas emission intensity (GHGI). Compared with CK treatments, the GWP of S15, S25 and S40 treatments was increased by 9.35~20.37%, 4.27~7.67% and 0.72~6.14%, respectively, among which the S15 treatment contributed the most to the GWP of farmland. GHGI is an evaluation index of low-carbon agriculture at this stage, which takes into account both crop yield and global warming potential. In this study, GHGI showed a different trend from GWP. Compared with CK treatments, the S25 treatments had no significant difference in 2020, and decreased significantly in 2021 and 2022. This is due to the combined effect of maize yield and cumulative greenhouse gas emissions, indicating that the appropriate straw returning method can not only reduce the intensity of greenhouse gas emissions but also improve soil productivity and enhance the carbon sequestration effect of farmland soil, which is an ideal soil improvement and fertilization measure.

[Orthopaedic robot assisted femoral neck dynamic cross fixation system for the treatment of femoral neck fractures].

OBJECTIVE: To explore and compare the clinical efficacy of orthopedic robot assisted femoral neck system （FNS） and traditional manual FNS in the treatment of femoral neck fractures in middle-aged and young people. METHODS: The clinical data of 62 consecutive patients with femoral neck fracture and age less than 65 years old admitted to the Intelligent Orthopaedic Department of Beijing Jishuitan Hospital from June 2021 to June 2022 were retrospectively analyzed. According to whether orthopedic robot-assisted surgery the patients were divided into two groups：30 patients aged 34 to 56 years old were treated with orthopedic robot assisted FNS internal fixation after closed or limited open reduction（experimental group）； 32 patients aged 33 to 54 years old underwent FNS internal fixation after closed or limited open reduction（control group）. The age, gender, time from injury to admission, average hospital stay, surgical duration, intraoperative bleeding volume, and intraoperative fluoroscopy frequency of two groups of patients were analyzed and compared. The hip joint function in both groups of patients was evaluated using the Harris hip joint scoring standard at 6 months after surgery. RESULTS: All 62 patients with femoral neck fractures successfully completed the surgery. There was no significant difference（P>0.05） between the experimental group and the control group in terms of baseline data such as age, gender, time from injury to admission, time from admission to surgery and the intraoperative bleeding. The surgical duration of the experimental group was significantly shorter than that of the control group [42.1（28.5, 50.7）min vs. 53.4（36.9, 62.5） min, Z=-2.338, P=0.019]. The intraoperative X-ray fluoroscopy frequency of the experimental group was significantly lower than that of the control group[8.0 （6.0, 11.0） times vs. 15.0（13.0, 17.0） times, Z=-5.960, P<0.001]. In terms of postoperative hip joint function, there was no significant difference in Harris score between the two groups of patients at 6-month follow-up（P>0.05）. CONCLUSION: Compared with manual operation of FNS, orthopedic robot assisted FNS in the treatment of femoral neck fractures can help shorten surgical time, reduce intraoperative fluoroscopy frequency, and have similar therapeutic effects on long-term hip joint function recovery.

[Effectiveness of proximal femur bionic nail for intertrochanteric fracture in the elderly].

Objective: To evaluate effectiveness of proximal femur bionic nail (PFBN) in treatment of intertrochanteric fractures in the elderly compared to the proximal femoral nail antirotation (PFNA). Methods: A retrospective analysis was made on 48 geriatric patients with intertrochanteric fractures, who met the selection criteria and were admitted between January 2020 and December 2022. Among them, 24 cases were treated with PFBN fixation after fracture reduction (PFBN group), and 24 cases were treated with PFNA fixation (PFNA group). There was no significant difference in baseline data such as age, gender, cause of injury, side and type of fracture, time from injury to operation, and preoperative mobility score, American Society of Anesthesiologists (ASA) score, Alzheimer's disease degree scoring, self-care ability score, osteoporosis degree (T value), and combined medical diseases between the two groups ( P>0.05). The operation time, intraoperative blood loss, number of blood transfusions, transfusion volume, length of hospital stay, occurrence of complications, weight-bearing time after operation, and postoperative visual analogue scale (VAS) score, walking ability score, mobility score, self-care ability score were recorded and compared between the two groups. And the radiographic assessment of fracture reduction quality and postoperative stability, and fracture healing time were recorded. Results: The operations in both groups were successfully completed. All patients were followed up 6-15 months with an average time of 9.8 months in PFBN group and 9.6 months in PFNA group. The operation time was significantly longer in PFBN group than in PFNA group ( P<0.05), but there was no significant difference in intraoperative blood loss, number of blood transfusions, transfusion volume, length of hospital stay, change in activity ability score, and change in self-care ability score between the two groups ( P>0.05). The weight-bearing time after operation was significantly shorter in PFBN group than in PFNA group ( P<0.05), and the postoperative VAS score and walking ability score were significantly better in PFBN group than in PFNA group ( P<0.05). Radiographic assessment showed no significant difference in fracture reduction scores and postoperative stability scores between the two groups ( P>0.05). All fractures healed and there was no significant difference in fracture healing time between the two groups ( P>0.05). The incidence of complications was significantly lower in PFBN group (16.7%, 4/24) than in PFNA group (45.8%, 11/24) ( P<0.05). Conclusion: Compared with PFNA, PFBN in the treatment of elderly intertrochanteric fractures can effectively relieve postoperative pain, shorten bed time, reduce the risk of complications, and facilitate the recovery of patients' hip joint function and walking ability.

Safety and effectiveness of fluorescence laparoscopy in precise hepatectomy: A meta-analysis.

BACKGROUND: To perform a systematic review of the safety and effectiveness of fluorescence laparoscopy-guided precise hepatectomy. METHODS: We searched the PubMed, Embase, Web of Science, and Cochrane Library databases from inception to December 1, 2022, using the search terms "indocyanine green," "ICG," "infracyanine green," "laparoscopy," "liver resection," and "hepatectomy." After performing a methodological quality assessment of the included studies, the overall results were subjected to meta-analysis using Review Manager 5.3. RESULTS: After screening, the meta-analysis included a total of 13 articles. The studies included 1,115 patients who were grouped into the fluorescence laparoscopy (490 patients) and conventional laparoscopy (625 patients) groups. All articles included in the meta-analysis were of high quality. The results of the meta-analysis revealed that compared to the conventional laparoscopy group, the fluorescence laparoscopy group had a higher R0 resection rate (odds ratio=4.03, 95% confidence interval [1.50, 10.83], P = 0.006), lower blood transfusion rate (odds ratio=0.46, 95% confidence interval [0.21, 0.97], P = 0.04) and lower blood loss (mean difference=-36.58; 95% confidence interval [-59.75, -13.41], P = 0.002). However, the length of hospital stay, operative time, and incidence of postoperative complications did not differ significantly between both groups (P>0.05). CONCLUSION: Compared to conventional laparoscopy, fluorescence laparoscopy provides better application effects in hepatectomy. The surgical procedure has demonstrated good safety and feasibility, which make it worthy of popularization.

Comparison of Robot-Assisted Percutaneous Cannulated Screws Versus Open Reduction and Internal Fixation in Calcaneal Fractures.

OBJECTIVE: Accurate placement of the screws is challenging in percutaneous cannulated screw fixation of calcaneal fractures, and robot-assisted (RA) surgery enhances the accuracy. We investigated the outcome of percutaneous cannulated screw fixation of Sander's type II and III calcaneal fractures. METHODS: This retrospective study analyzed clinical data of 26 patients with fresh closed calcaneal fractures (28 fractures) who were admitted to our center from January 2022 to July 2022. All fractures were divided into the RA group and the open reduction and internal fixation (ORIF) group according to the surgeries performed. RA surgery was performed by closed reduction or open reduction combined with a tarsal sinus approach. Age, sex, operation time, preoperative waiting time, length of postoperative hospital stay, wound complications, and American Orthopaedic Foot and Ankle Society Ankle Hindfoot Scale (AOFAS) at 3 months postoperatively were compared. Preoperative and postoperative radiographic parameters (calcaneal length, width, height, Böhler angle, and fixation rate of the sustentaculum tali) were documented. The chi-square test, one-way analysis of variance, and Wilcoxon test were used for the comparison of categorical, normally distributed, and nonnormally distributed continuous variables, respectively. RESULTS: The calcaneal width, height, and Böhler angle were significantly corrected postoperatively in both groups. The postoperative calcaneal lengths in both groups were also corrected. However, no significant difference was found. No significant differences in calcaneal length, width, height, and Böhler angle were observed between the two groups. The operation time (p < 0.001), preoperative waiting time (p < 0.001), and length of postoperative hospital stay (p = 0.003) in the RA surgery group were significantly shorter than those in the ORIF group. The fixation rate of the sustentaculum tali (p < 0.001) in the RA surgery group was significantly superior to that in the ORIF group. All wound complications occurred in the ORIF group. All fractures healed within 3 months. The AOFAS scores at 3 months postoperatively were not significantly different. CONCLUSION: RA percutaneous screw fixation of the calcaneal fracture is a safe, effective, rapid, and minimally invasive surgical option for surgeons.

Effectiveness and Accuracy of a Patient-Specific Instrumentation System for Total Hip Arthroplasty.

OBJECTIVE: Traditional total hip arthroplasty (THA) is often performed by visual inspection due to the lack of reliable reference, which results in inappropriate position of prosthesis and poor outcomes. This study attempts to introduce a novel patient-specific instrumentation (PSI) system and assess its effectiveness and accuracy compared with freehand operation and robot system through bone model experiments. METHODS: Equally divide 30 sawbone models into the freehand group, PSI group, and robot group. Ten sets of prosthesis parameters were randomly generated as planning, and the three groups underwent simulated THA depending on these parameters. After the placement of the femoral prosthesis, the acetabular anteversion plan was adjusted in the PSI and robot groups so that the combined anteversion was maintained before and after adjustment. After the surgery, the actual prosthesis parameters of all bone models were measured and analyzed statistically. RESULTS: No statistically significant difference was found in femoral anteversion error among the three groups (p = 0.951). The errors of acetabular cup anteversion, acetabular cup abduction, and combined anteversion in PSI group were 3.92° (2.94°, 4.62°), 5.65° (4.63°, 6.70°), and 3.93° (2.94°, 4.62°), respectively, which were significantly smaller than those in the freehand group [11.84° (9.92°, 13.87°), 13.54° (9.81°, 15.21°), 16.04° (8.18°, 19.25°), respectively, p < 0.05], but significantly larger than those in the robot group [1.34° (0.98°, 1.70°), 1.80° (1°, 2.02°), 1.34° (0.98°, 1.70°), respectively, p < 0.05]. CONCLUSION: Compared with the traditional freehand operation, the patient-specific instrumentation system is feasible in total hip arthroplasty because it improves the accuracy of prosthesis placement. In addition, the rapid measurement of intraoperative femoral prosthesis parameters can help surgeons optimize preoperative planning.

Pharmacological conversion of gut epithelial cells into insulin-producing cells lowers glycemia in diabetic animals.

As a highly regenerative organ, the intestine is a promising source for cellular reprogramming for replacing lost pancreatic ß cells in diabetes. Gut enterochromaffin cells can be converted to insulin-producing cells by forkhead box O1 (FoxO1) ablation, but their numbers are limited. In this study, we report that insulin-immunoreactive cells with Paneth/goblet cell features are present in human fetal intestine. Accordingly, lineage-tracing experiments show that, upon genetic or pharmacologic FoxO1 ablation, the Paneth/goblet lineage can also undergo conversion to the insulin lineage. We designed a screening platform in gut organoids to accurately quantitate ß-like cell reprogramming and fine-tune a combination treatment to increase the efficiency of the conversion process in mice and human adult intestinal organoids. We identified a triple blockade of FOXO1, Notch, and TGF-ß that, when tested in insulin-deficient streptozotocin (STZ) or NOD diabetic animals, resulted in near normalization of glucose levels, associated with the generation of intestinal insulin-producing cells. The findings illustrate a therapeutic approach for replacing insulin treatment in diabetes.

[Orthopedic robot based on 5G technology for remote navigation of percutaneous screw fixation in pelvic and acetabular fractures].

Objective: To investigate the accuracy and safety of percutaneous screw fixation for pelvic and acetabular fractures with remote navigation of orthopedic robot based on 5G technology. Methods: Between January 2021 and December 2021, 15 patients with pelvic and/or acetabular fractures were treated with percutaneous screws fixation which were placed by remote navigation of orthopedic robot based on 5G technology. There were 8 males and 7 females. The age ranged from 20 to 98 years, with an average of 52.1 years. The causes of trauma included traffic accident injury in 6 cases, falling from height injury in 6 cases, fall injury in 2 cases, and heavy object smashing injury in 1 case. The time from injury to operation ranged from 3 to 32 days, with an average of 10.9 days. There were 8 cases of simple pelvic fractures, 2 simple acetabular fractures, and 5 both pelvic and acetabular fractures. There were 7 cases of pelvic fractures of Tile type B2, 2 type B3, 1 type C1, and 3 type C2; 4 cases of unilateral anterior column fracture of the acetabulum, 2 bilateral anterior column fractures, and 1 anterior wall fracture. CT images within 5 days after operation were collected for screw position assessment. The screw planning time and guidewire placement time were recorded, as well as the presence of intraoperative adverse events and complications within 5 days after operation. Results: All patients achieved satisfactory surgical results. A total of 36 percutaneous screws were inserted (20 sacroiliac screws, 6 LC Ⅱ screws, 9 anterior column screws, and 1 acetabular apical screw). In terms of screw position evaluation, 32 screws (88.89%) were excellent and 4 screws (11.11%) were good; there was no screw penetrating cortical bone. The screw planning time ranged from 4 to 15 minutes, with an average of 8.7 minutes. The guidewire placement time ranged from 3 to 10 minutes, with an average of 6.8 minutes. The communication delayed in 2 cases, but the operation progress was not affected, and no serious intraoperative adverse events occurred. No delayed vascular or nerve injury, infection, or other complications occurred within 5 days after operation. No cases need surgical revision. Conclusion: The fixation of pelvic and acetabular fractures by percutaneous screw with remote navigation of orthopedic robot based on 5G technology is accurate, safe, and reliable.

Percutaneous Robot-Assisted versus Freehand S2 Iliosacral Screw Fixation in Unstable Posterior Pelvic Ring Fracture.

OBJECTIVES: To assess the efficiency, safety, and accuracy of S2 (IS) screw fixation using a robot-assisted method compared with a freehand method. METHODS: This is a retrospective clinical study. We analyzed the patients treated with S2 IS screw fixation for unstable pelvic fractures from January 2016 to January 2019 in our institution. Sixty-three patients (17 men and 46 women) aged between 21 and 55 years (with an average age of 39.22 ± 9.28) were included in this study. According to the Tile classification, there were 26 (41.3%) type B fractures and 37 (58.7%) type C fractures. All patients were divided into robot-assisted (RA) group (38 patients) or the traditional freehand (FH) group (25 patients). In RA group, the S2 IS screws were implanted with a robot-assisted technique. And S2 IS screws were implanted with a traditional freehand technique in FH group. The screw-related complications were recorded during and after the surgery. The position of all screws and fracture reduction was assessed by postoperative CT scans according to the Gras classification. The number of guide wire attempts and the radiation exposure for S2 screw implantation during operation were also recorded. Finally, the Matta standard was used to evaluate the fracture reduction of the IS joint. RESULTS: A total of 89 IS screws were implanted into S2 iliosacral joint. Fifty-four screws were placed by RA (38 patients) and 35 screws were by FH (25 patients). There was no difference between the two groups with respect to demographic data. There was no screw-related complications or revision surgery in any group. In terms of screw placement, the excellent and good rate was 100% in the RA group, better than that in the FH group where it was only 85.7% (P < 0.001). The fluoroscopy time was 8.06 ± 3.54 s in RA group, which was much less than that in the FH group (27.37 ± 8.82 s, P < 0.001). The guide wire attempts in the RA group (0.685 ± 0.820) were much less than those in the FH group (5.77 ± 3.34) (P < 0.001). Both the fluoroscopy time per screw and the number of guide wire attempts in the RA group were much less than those in the FH group (P < 0.001). The overall postoperative excellent and good rate of Matta standard in RA and FH groups were 86.8% (34/4) and 90.0% (23/25), respectively (P = 0.750), and there was no statistical difference. CONCLUSION: The robot-assisted surgery is an accurate and minimally invasive technique. S2 IS screw implantation assisted by TiRobot to treat the posterior pelvic ring fractures, have a high success rate than the freehand technique. Percutaneous RA S2 IS screw fixation for unstable posterior pelvic ring injuries is safe and clinically feasible and has great clinical application value.

Effect of Local Delivery of Vancomycin and Tobramycin on Bone Regeneration.

OBJECTIVE: A bone defect rat model was established to investigate the osteogenic effect of local delivery two antibiotics (vancomycin and tobramycin powder) on bone regeneration. METHODS: Twenty-four Sprague-Dawley (SD) male rats (6 to 8 weeks, 200 to 250 g) were used in this study. All these rats were randomly divided into four groups. Based on dose conversion between rat and human via body surface area, the rat dose of two antibiotics was 88µg/g and 176 µg/g for vancomycin and tobramycin, respectively. Con group (no antibiotic), Van group (vancomycin, 88 µg/g), Tob group (tobramycin 176 µg/g), and Van+Tob group (vancomycin 88µg/g combined with tobramycin 176 µg/g). A 5.0-mm full-thickness standardized mandibular bone defect was performed with a drill in each rat and different antibiotic powders were placed over the bone defect space, respectively. All these animals were sacrificed after 12 weeks post-operation. The mandible bones were harvested for further radiographic and histologic analysis. The bone volume/total volume (BV/TV) ratio, bone volume (BV), and bone fractional area (BFA) in the defect area via micro-computed tomography (µCT scanning) were further analyzed. Then, we performed a histological assessment via hematoxylin and eosin (H&E) and Masson's trichrome staining to analyze bone regeneration and also analyze the number of osteoblasts per filed. RESULTS: There were no postoperative deaths, signs of vancomycin-related or tobramycin-related toxicity, or signs of systemic illness in any of the four groups. All wounds healed well, and no complications or surgical site infection were observed in all rats. From the µCT scans analyses, there was less bone regeneration in the Van group than in the Con group (BV/TV: F = 64.29, R2  = 0.9602; P = 0.0052; BFA: F = 76.17, R2  = 0.9662, P = 0.0007; BV: F = 194.4, R2  = 0.9865, P = 0.0022). However, when the tobramycin and vancomycin were combined, an increase in bone defect re-ossification was found in the Van+Tob group than in the Van group (BV/TV: F = 64.29, R2  = 0.9602, P = 0.0033; BFA: F = 76.17, R2  = 0.9662, P = 0.0006; BV: F = 194.4, R2  = 0.9865, P = 0.0033). Routine H&E and Masson staining supported the finding of µCT scanning. Quantitative indices confirmed that both the bone regeneration and the number of osteoblasts per filed in the defect area was higher in the Van+Tob group than in the Van group (percentage of bone tissue: F = 145.7, R2  = 0.9562, P = 0.0008; number of osteoblasts per file; F = 67.3, R2  = 0.9098, P < 0.0001). There was no significant difference between the Con group and the Van+Tob group on the number of osteoblasts each field (F = 145.7, R2  = 0.9562, P > 0.9999). CONCLUSION: For bone defect, local application of vancomycin combined with tobramycin was recommended over vancomycin alone. This animal study presents data suggesting that the use of local delivery of vancomycin and tobramycin should be investigated further in clinical studies.

Evaluation of a Bi-Planar Robot Navigation System for Insertion of Cannulated Screws in Femoral Neck Fractures.

OBJECTIVE: To evaluate the bi-planar robot navigation system for insertion of cannulated screws in femoral neck fractures. METHOD: Between January 2016 and December 2016, 60 patients with femoral neck fractures were separately treated using percutaneous cannulated screws assisted by the bi-planar robot navigation system (robot group) and conventional freehand surgery (freehand group). The fluoroscopy time, the number of drilling attempts, and the operation time were recorded during operations; the dispersion and parallelism of the cannulated screws on the posteroanterior and lateral images were measured after operations. Patients were followed up for 12-24 months and the Harris scores and the final results of the two groups were compared. RESULTS: During bi-planar robot navigation system-assisted surgery, the fluoroscopy time for acquisition of images was 2.3 seconds on average, and the time for planning screws during the operation was 2.8 min on average. The average fluoroscopy time during the placement of the guide pin was 5.7 seconds and 14.14 seconds (P = 0.00), respectively. The average time of the placement of the cannulated screws was 12.7 min and 19.4 min (P = 0.00), respectively, in the robot group and the freehand group. In the robot group, only one guide pin was replaced during the operation, and the average number of adjustments for each guide pin was 2.39 in the freehand group. The screw parallelism and dispersion measured by postoperative imaging in the robot group were significantly superior to those in the freehand group. From postoperative CT it was evident that there were 5 cases of screws exiting the posterior cortex in both groups. During the follow-up phase, 1 case of femoral head necrosis and 5 cases of femoral neck shortening of more than 10 mm occurred in the robotic navigation group; 3 cases of femoral head necrosis, 1 case of fracture nonunion, and 2 cases of shortening of more than 10 mm occurred in the freehand group. At 18 months after surgery, the average Harris scores of the patients were 85.20 and 83.45, respectively, with no significant difference. CONCLUSION: Using bi-planar robot navigation system-assisted placement of femoral neck cannulated screws can significantly reduce the time of intraoperative fluoroscopy, drilling attempts, and operation time. The placed screws are superior to the screws placed freehand in relation to parallelism and dispersion. However, it is still necessary for surgeons to have a good reduction of the femoral neck fracture before surgery and to be proficient in the operation of the robot navigation system. In summary, the bi-planar robot navigation system is an effective assistant instrument for surgery.

Guidance for Treatment of Pelvic Acetabular Injuries with Precise Minimally Invasive Internal Fixation Based on the Orthopaedic Surgery Robot Positioning System.

Pelvic acetabular fracture is a common kind of fracture, mostly caused by high energy injuries. It is associated with high mortality and disability rates. The aim of surgical treatment of pelvic acetabular fractures is to restore the symmetry and stability of the pelvic ring structure and the anatomical structure of acetabular. Open reduction internal fixation is often used for the treatment of such fractures, but open surgery is in cases of serious injury, more bleeding, and high risk of infection. With the development of minimally invasive technology and the concept of the bone channel structure, the percutaneous lag screw technique for the treatment of pelvic and acetabular fractures has been applied in clinical practice and has proven to be effective. However, the anatomical structure of the pelvis and acetabulum is complex, and there are many important nerves and vessels adjacent to it. Traditional fluoroscopy screw placement is prone to screw malposition, and even minor angle changes may lead to screw perforation and damage of nerve vessels. The problem of radiation exposure is also noteworthy. Robotic-assisted surgery can be used to carry out screw position planning through preoperative imaging, intraoperative real-time tracking, and mechanical arm assistance to ensure that the screw placement position is consistent with the planning. In this way, robotic-assisted surgery can be used to accurately insert lag screws, and can reduce surgical risk and radiation exposure. This guide uses the TiRobot system as an example to describe the application of robot surgery in detail, aiming at standardizing the application of robots in orthopaedic surgery.

Guidance for the Treatment of Femoral Neck Fracture with Precise Minimally Invasive Internal Fixation Based on the Orthopaedic Surgery Robot Positioning System.

Femoral neck fractures are among the most common fractures in orthopaedics. There are many surgical methods for the treatment of femoral neck fracture. Percutaneous cannulated lag screw fixation for the treatment of femoral neck fractures is favored by orthopaedic doctors because of its characteristics of being minimally invasive, with less bleeding and firm fixation. However, traditional freehand screw placement is limited by many factors, and the screw malposition rate is very high, which directly leads to the reduction of its biomechanical stability, and even leads to the ischemic necrosis of the femoral head caused by damage to blood vessels. In addition, excessive attempts to drill holes can damage cancellous bone and affect the screw's holding force, which reduces the stability of internal fixation and increases the risk of failure. At the same time, too much radiation exposure to medical personnel and patients also causes great damage to the body. Robot-assisted orthopaedic surgery combines the mechanical "eye" (an infrared ray tracking device) and the mechanical "hand" (six degrees of freedom mechanical arm), and through the process of preoperative planning, intraoperative assistance in screw placement, and postoperative confirmation, provides a more minimally invasive and precise treatment method for this kind of surgery, and significantly reduces radiation exposure. This guide uses the TiRobot system as an example to describe the robot surgery in detail, aiming at standardizing the application of robots in orthopaedic surgery.

Circ-SATB2 upregulates STIM1 expression and regulates vascular smooth muscle cell proliferation and differentiation through miR-939.

The prevention and treatment of coronary heart disease (CHD) is a difficult problem to be solved. More and more studies have found that circular RNAs (circRNAs) may play important roles in the development of CHD. Here detection of vascular smooth muscle cells (VSMCs) showed that circ-SATB2 and STIM1 were up-regulated in proliferative VSMCs, while miR-939 were down-regulated. Circ-SATB2 and miR-939 did not affect the expression of each other, but circ-SATB2 could promote while miR-939 inhibited the expression of STIM1 (a target gene of miR-939). Circ-SATB2 overexpression could inhibit the expression of SM22-alpha (SM22α, a marker of contractile VSMCs), while the expression of SM22α was promoted by miR-939. STIM1 could promote cell proliferation and migration, and circ-SATB2 had similar effects, but its linear sequence had no such functions. MiR-939 had the opposite effects, could promote cell apoptosis and inhibit cell proliferation and migration, and siRNAs targeting circ-SATB2 had similar effects. When co-transfected with circ-SATB2 over-expression vector and miR-939 mimics or STIM1 siRNAs, the changes of cell proliferation, apoptosis and migration were not significant. Therefore, circ-SATB2 can regulate VSMC phenotypic differentiation, proliferation, apoptosis and migration by promoting the expression of STIM1. This discovery will provide a theoretical reference for exploring the role of circRNA in VSMCs and the pathogenesis of CHD.

Insight into the surfactin production of Bacillus velezensis B006 through metabolomics analysis.

Bacillus velezensis B006 is a biocontrol agent which functions through effective colonization and surfactin production. To reveal the surfactin-producing mechanism, gas chromatography-mass spectrometry based untargeted metabolomics was performed to compare the metabolite profiles of strain B006 grown in industrial media M3 and M4. Based on the statistical and pathway topology analyses, a total of 31 metabolites with a fold change of less than - 1.0 were screened as the significantly altered metabolites, which distributed in 15 metabolic pathways. Fourteen amino acids involving in the metabolisms of alanine/aspartate/glutamate, glycine/serine/threonine, arginine/proline, glutathione/cysteine/methionine and valine/leucine/isoleucine as well as succinic acid in TCA cycle were identified to be the hub metabolites. Aminoacyl-tRNA biosynthesis, glycerolipid metabolism, and pantothenate/CoA biosynthesis also contributed to surfactin production. To the best of our knowledge, this study is the first to investigate the metabolic pathways of B. velezensis on surfactin production, and will benefit the optimization of commercial fermentation for higher surfactin yield.

Influence of the quality of intraoperative fluoroscopic images on the spatial positioning accuracy of a CAOS system.

BACKGROUND: Spatial positioning accuracy is a key issue in a computer-assisted orthopaedic surgery (CAOS) system. Since intraoperative fluoroscopic images are one of the most important input data to the CAOS system, the quality of these images should have a significant influence on the accuracy of the CAOS system. But the regularities and mechanism of the influence of the quality of intraoperative images on the accuracy of a CAOS system have yet to be studied. METHODS: Two typical spatial positioning methods - a C-arm calibration-based method and a bi-planar positioning method - are used to study the influence of different image quality parameters, such as resolution, distortion, contrast and signal-to-noise ratio, on positioning accuracy. The error propagation rules of image error in different spatial positioning methods are analyzed by the Monte Carlo method. RESULTS: Correlation analysis showed that resolution and distortion had a significant influence on spatial positioning accuracy. In addition the C-arm calibration-based method was more sensitive to image distortion, while the bi-planar positioning method was more susceptible to image resolution. The image contrast and signal-to-noise ratio have no significant influence on the spatial positioning accuracy. The result of Monte Carlo analysis proved that generally the bi-planar positioning method was more sensitive to image quality than the C-arm calibration-based method. CONCLUSIONS: The quality of intraoperative fluoroscopic images is a key issue in the spatial positioning accuracy of a CAOS system. Although the 2 typical positioning methods have very similar mathematical principles, they showed different sensitivities to different image quality parameters. The result of this research may help to create a realistic standard for intraoperative fluoroscopic images for CAOS systems.