Intelligent Carbon Dots with Switchable Photo-Activated Oxidase-Mimicking Activity and pH Responsive Antioxidant Activity Adaptive to the Wound Microenvironment for Selective Antibacterial Therapy.

Intelligent antibacterial agent with controllable activities adaptive to the wound microenvironment is appealing to reduce drug resistance and enhance antibacterial efficiency. In this study, celery is chosen as the carbon source to construct celery-based carbon dots (CECDs) with double activities, i.e., reactive oxygen species (ROS)-production and ROS-clearance activities. The ROS-production capability of CECDs is dependent on the oxidase (OXD)-mimicking activity, which is only photo-activated and thus artificially controlled by light to avoid the production of excess ROS. Meanwhile, the optimal OXD-mimicking activity occurrs at the pH of 5, close to microenvironmental pH at the bacterial infection site, which will enhance the antibacterial efficacy. On the other hand, CECDs exhibit the antioxidant activity at the neutral or weak alkaline pH, which will assist the healing of the wound. Thus, the conversion of ROS-production and ROS-clearance ability of CECDs can be dynamically and intelligently switched automatically with microenvironmental pH at different stages of treatment (from acid to neutral/weak basic). The proposed CECDs exert adorable selective antibacterial activity against Gram-positive bacteria and satisfactory therapeutic effect on bacteria infected mice. This study paves a new avenue to design the intelligent antibacterial nanoagent sensitive to the infected microenvironmental condition, reducing drug resistance and assisting precise medicine.

Predictors of Adverse Pregnancy Outcomes Following Traumatic Injuries.

OBJECTIVE: After traumatic injury in pregnant women, providing timely and appropriate management for high-risk patients is crucial for both pregnant women and fetuses. This study aimed to identify risk factors that predict adverse pregnancy outcomes after traumatic injury. METHODS: A retrospective cohort study including 317 pregnant patients who experienced trauma was conducted. The collected data included general demographics, injury mechanisms and adverse pregnancy outcomes. Patients were divided into two subgroups based on the absence or presence of trauma-related adverse pregnancy outcomes. Univariate and multivariate logistic regressions were conducted to estimate the associations between clinical variables and adverse pregnancy outcomes. RESULTS: A total of 41 (12.93%) patients experienced adverse pregnancy outcomes within the first 24 h post-trauma. This study revealed that age >35 years (OR=14.995, 95% CI: 5.024-44.755, P<0.001), third trimester trauma (OR=3.878, 95% CI: 1.343-11.204, P=0.012), abdominal pain (OR=3.032, 95% CI: 1.221-7.527, P=0.017), vaginal bleeding (OR=3.226, 95% CI: 1.093-9.523, P=0.034), positive scan in focused assessment with sonography for trauma (FAST) positive (OR=8.496, 95% CI: 2.825-25.555, P<0.001), 9≤ injury severity score (ISS) <16 (OR=3.039, 95% CI: 1.046-8.835, P=0.041) and ISS≥16 (OR=5.553, 95% CI: 1.387-22.225, P=0.015) increased the probability of posttraumatic adverse pregnancy outcomes. Maternal age, gestational age at delivery, vaginal bleeding and positive FAST results were risk factors for abnormal delivery. CONCLUSION: Advanced maternal age, third trimester, and positive FAST results should alert multidisciplinary trauma teams to closely monitor patients to prevent adverse pregnancy outcomes.

Lumbopelvic fixation with S2 alar-iliac screws for U-shaped sacral fractures.

OBJECTIVE: To investigate the surgical methods and clinical effects of lumbopelvic fixation (LPF) with S2 alar-iliac (S2AI) screws for U-shaped sacral fractures. METHODS: From December 2019 to August 2020, 14 patients with U-shaped sacral fractures were treated with LPF using S2AI screws. Demographics, fracture classification, mechanism of injury, surgical treatment, complications and clinical results were assessed. All patients had a LPF with or without nerve decompression. The reduction quality was evaluated according to the Matta criteria. Neurological function was evaluated according to the Gibbons grading. The activities of daily life were evaluated according to the Majeed scoring system at the last follow-up. RESULTS: Among 14 consecutive patients with U-shaped sacral fractures, the age at injury ranged from 13 to 72 years (average 30.3 ± 17.5 years). There were 4 males and 10 females. All patients were followed up for 6-15 months (average 7.8 ± 2.7 months). Thirteen patients were fixed with bilateral S2AI screws, and one patient was fixed only unilaterally due to unilateral spinopelvic dissociation. The excellent and good rate of postoperative pelvic reduction quality was 92% (excellent 10, good 3, fair 1). At the latest follow-up, the excellent and good rate of pelvic function was 100% (excellent 9, good 5) and all patients achieved different extents of neurological recovery. One patient had a postoperative superficial surgical site infection, which healed after debridement. Radiological examination at 3-6 months after operation showed that all fractures had healed. No complications were found in any patients during follow-up, such as implant fracture, loss of reduction, deep wound infection, wound dehiscence and screw protrusion discomfort. CONCLUSION: LPF with S2AI screws for the treatment of U-shaped sacral fractures has exhibited distinct advantages, including firm fixation, a low rate of surgical site complications and satisfactory clinical efficacy. This approach provides sufficient stability to accelerate the commencement of postoperative rehabilitation.

Pelvic incidence-guided reduction in transverse parts of U-shaped sacral fractures: Technical recommendations.

OBJECTIVE: The purpose of this study is to present a surgical technique that simultaneously reduces and fixates the transverse parts of U-shaped sacral fractures. METHODS: The sacral fracture was exposed through a posterior median approach. In a flexion injury, the rotation of the lower sacral segment is reduced by distraction along a pre-curved rod. Then, lordotic restoration is performed with a Weber clamp placed at the lower sacral segment through dragging. In an extension injury, longitudinal distraction is performed along the spinopelvic rod to reduce the vertical displacement. Next, the transverse displacement is reduced by a dissector placed between the upper and lower sacral segments through levering. The sagittal reduction on the lateral pelvic view was judged by PI. A regression analysis of Oswestry disability index (ODI) with Z-scores of PI, lumbar lordosis (LL), sacral slope (SS), and pelvic tilt (PT) was performed. RESULTS: At the 1-year follow-up, the average PI, LL, SS, and PT values were 51.6 (range: 43.1-76.0), 44.8 (34.6 - 60.1), 35.4 (18.1 - 48.0), and 16.7 (2.2-35.4) degrees, respectively. All patients were able to maintain an upright stance. The average ODI was 27.6% (2-72%). Surprisingly, the regression analysis demonstrated a significant linear relationship between ODI and LL (R2 = 0.367, p = .048) but not between ODI and PI (R2 = 0.227, p = .138). CONCLUSIONS: Using PI as guidance, the surgical procedures were helpful to reduce the PI of transverse sacral fractures into the normal range. However, the relationship between PI and the prognosis remains to be evaluated by future researches.

Sacral osteotomy combined with triangular osteosynthesis in the treatment of malunion and nonunion of vertically displaced pelvic fractures.

BACKGROUND: Malunion and nonunion of vertically displaced pelvic fractures result in lower limb length discrepancies, claudication, and pain. There have been few previous reports of this type of corrective surgery for these old pelvic fractures. We present a surgical technique of sacral osteotomy combined with triangular osteosynthesis in the treatment of malunion and nonunion of vertically displaced pelvic fractures and report on its short-term clinical results. METHODS: We retrospectively reviewed nine patients (five males and four females) with malunion or nonunion of vertically displaced pelvic fractures treated with sacral osteotomy and triangular osteosynthesis from April 2015 to January 2020. The age ranged from 14 to 45 years (average, 30.7 years). The time from injury to deformity correction surgery ranged from 3 months to 5 years (average, 12.8 months). The vertical displacement of a unilateral hemipelvis was 3.0-4.5 cm (average, 3.80 cm). According to AO/OTA classification at the initial fracture, there are eight cases in type C1.3 and one case in type C3.3. Sacral osteotomy and triangular osteosynthesis were used in all nine patients. The degree of unilateral hemipelvic reduction was assessed postoperatively based on measurements from the anteroposterior (AP) X-ray. Majeed score and pain visual analog scale (VAS) were used to assess the therapeutic effect of the patients during follow-up. RESULTS: In all nine patients, postoperative AP X-ray showed correction displacement of 1.7-3.9 cm (average, 3.20 cm). All the patients were followed up for 6-36 months (average, 12.7 months). At the last follow-up, the Majeed score of pelvic fracture increased from an average of 53.9 points (30-84 points) preoperatively to 87.0 points (72-94 points), and the VAS score for pain decreased from an average of 6.0 points (4-8 points) preoperatively to 1.2 points (0-3 points). None had complications like infection, implant broken, screw loosening, iatrogenic nerve, and blood vessel injury. CONCLUSION: Sacral osteotomy combined with triangular osteosynthesis for the treatment of pelvic malunion and nonunion caused by sacral fractures can correct significantly vertical displacement of a unilateral pelvis, prolong limb length, and reconstruct the stability of a pelvic ring, achieving good clinical results.