Honggang Xia

Rib fractures, particularly multiple fractures, are common in patients with chest trauma and can lead to complications and an increased risk of mortality.

Background: In rib fractures, infection of the fracture ends can affect the use of the implant, causing surgical failures. Molybdenum disulfide with silver phosphate [MoS₂(S)-Ag₃PO₄] coating for titanium plates has bactericidal effects in vitro. This study aimed to determine the most optimal MoS₂(S)-Ag₃PO₄ coating for fracture healing in a novel rabbit rib fracture infection (RFI) model. This study hypothesizes that MoS₂(S)-Ag₃PO₄ coated titanium implants will reduce bacterial infection and inflammation, while promoting osteogenesis and fracture healing in a rabbit RFI model. Methods: Twenty rabbits were used to create the RFI model using 0, 1×10⁵, 1×10⁶, and 1×10⁷ colony-forming units (CFU)/mL of Staphylococcus aureus culture. Twelve rabbits were used to test titanium (Ti) vs. titanium MoS₂(S)-Ag₃PO₄-coated (Ti-MoS₂-Ag₃PO₄) (with 808-nm near-infrared light irradiation) fixators on rib fractures with S. aureus. Tissues were examined using hematoxylin-eosin (HE) and safranin-O staining. Western blotting was performed for interleukin (IL)-6 and tumor necrosis factor (TNF)-α. MoS₂(S)-Ag₃PO₄ safety was assessed using hemolysis, blood assays, and major organ histology. Antibacterial efficacy was tested using Gram staining and bacterial cultures. Results: In the negative control (NC) group, the incision healed well, but the 1×10⁵, 1×10⁶, and 1×10⁷ CFU/mL groups showed pus coating and abscesses. IL-6 and TNF-α expression in the infected groups was significantly higher than in the NC group (all Pvs. the NC group (all P2, and Ti-MoS₂-Ag₃PO₄ were biocompatible according to the hemolysis and biochemistry assays and major organ histology. Dense bacterial accumulation was seen in the Ti group, while the Ti-MoS₂-Ag₃PO₄ group showed sparse bacterial colonies, achieving a 99.43% antibacterial rate. Conclusion: An RFI model was successfully constructed in rabbits. MoS₂-Ag₃PO₄-coated titanium implants appear to be biocompatible and able to manage infection in a rabbit model of RFI.

BACKGROUND: Rib fractures are one of the most common blunt injuries, accounting for approximately 10% of all trauma patients and 60% of thoracic injuries. Multiple rib fractures, especially flail chest, can cause local chest wall softening due to the loss of rib support, leading to paradoxical breathing, severe pain, and a high likelihood of accompanying lung contusions. OBJECTIVE: This study investigates the mechanical properties of a new polymer material rib internal fixator to provide theoretical data for its clinical use. METHODS: We conducted in vitro mechanical tests on 20 fresh caudal fin sheep ribs, using different fracture models across four randomly assigned groups (five ribs per group). The fixators were assessed using non-destructive three-point bending, torsion, and unilateral compression tests, with results averaged. Additionally, finite element analysis compared stress and strain in the polymer fixators and titanium alloy rib plates during bending and torsion tests. RESULTS: In vitro tests showed that the polymer fixators handled loads effectively up to a maximum without increase beyond a certain displacement. Bending and torsion tests via finite element analysis showed the polymer material sustained lower maximum equivalent stresses (84.455 MPa and 14.426 MPa) compared to titanium alloy plates (219.88 MPa and 46.47 MPa). CONCLUSION: The polymer rib fixator demonstrated sufficient strength for rib fracture fixation and was superior in stress management compared to titanium alloy plates in both bending and torsion tests, supporting its potential clinical application.

Medical tools and implants used in clinics can be contaminated with bacteria even with disinfection treatment. To avert this situation, titanium (Ti) plates modified with a MoS₂(S)–Ag₃PO₄ coating were designed to kill Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) effectively under near-infrared (NIR) light irradiation. The introduction of Ag₃PO₄ nanoparticles (NPs) reduced the bandgap of MoS₂ and suppressed the recombination of the photogenerated electron–hole pairs. Therefore, Ti–MoS₂(S)–Ag₃PO₄ exhibited a higher photocatalytic performance, leading to the generation of more radical oxygen species (ROS). Furthermore, cooperating with the good photothermal performance of MoS₂, the MoS₂(S)–Ag₃PO₄ coating exhibited a high antibacterial efficacy of 99.76 ± 0.15% and 99.85 ± 0.09% against S. aureus and E. coli, respectively, for 15 min in vitro. Moreover, the MoS₂(S)–Ag₃PO₄ coating had no apparent toxicity to cells. The proposed strategy may provide new insights for rapidly eradicating bacteria on medical tools and superficial implants.

Background: The effects of transthyretin (TTR) over-expression on the proliferation and cell cycle of nonsmall cell lung cancer (NSCLC) A549 cells and its possible mechanism were verified. Methods: A total of 196 LC patients and 20 healthy controls were enrolled at Tianjin Hospital, Tianjin, China between Apr 2017 and Oct 2017. The serum TTR content was detected by ELISA. Through lentiviral transfection method, NSCLC cells were divided into non-transfected group (group A), negative control group (group B) transfected with empty vector and experimental group (group C) transfected with TTR overexpression. Cell proliferation was detected by CCK-8 method, TTR mRNA expression was detected by realtime quantitative polymerase chain reaction (RT-qPCR), and TTR protein expression was tested by Western blot (WB). Cell cycle was detected by flow cytometry, Wnt3a/β-catenin protein expression was detected by WB, and mRNA expression was detected by RT-qPCR. Results: The serum TTR content in early, middle and late LC group was remarkably lower than that in healthy group (P<0.05). Compared with late stage, TTR content in early and middle stages of LC group was higher, and the difference was statistically marked (P < 0.05). The absorbance value of group C was lower than that of groups A and B, indicating that the cell proliferation activity dramatically decreased, with statistically marked difference (P<0.05). LC A549 cells in group C were obviously blocked in G2M, with statistical significance (P<0.05). Conclusion: TTR over-expression can inhibit the proliferation of NSCLC A549 cells, and the expression is related to Wnt3a/β-catenin pathway. TTR in serum of patients was helpful for diagnosing LC and has certain clinical value.

Application value of rib surface positioning ruler combined with volumetric CT measurement in selection of the incision for minimally invasive internal fixation of rib fracture was investigated. A total of 80 patients who received internal fixation of rib fractures in Tianjin Hospital Affiliated to Tianjin University (Tianjin, China) from May 2018 to April 2019 were selected. Patients were treated with the rib surface positioning ruler combined with volumetric CT measurement method (n=42) or traditional positioning method (n=38). The following parameters were compared between the two groups: Preset incision accuracy, operation incision length, operation time, intraoperative bleeding volume, postoperative wound drainage volume and postoperative pain score. Compared with the traditional positioning method, rib surface positioning ruler combined with volumetric CT measurement method can improve preset incision accuracy, reduce operation time, incision length, intraoperative bleeding volume, postoperative wound drainage volume, and postoperative pain score, with statistically significant differences (P<0.05). In conclusion, the application of rib surface positioning ruler combined with volumetric CT measurement technique has obvious effect on the selection of incision for internal fixation of rib fracture, and is an effective method worth promoting.

Chest trauma accounts for ~13.5% of all traumas, and direct death from chest trauma accounts for 20‑25% of all traumatic deaths. Chest trauma is the second cause of death from trauma. Frequent rib fractures, especially in patients with flail chest, often cause severe pain, chest wall softening, abnormal breathing and severe lung contusion and laceration, usually requiring thoracic surgery. In recent years, the open reduction and internal fixation treatment of rib fractures with flail chest has achieved satisfactory results, and some surgical indications have reached consensus. A number of scholars and medical centers have demonstrated the practicality and cost‑effectiveness of rib fixation in flail chest, including the small incidence of pulmonary complications, the short ICU mechanical ventilation time, and the reduction of digestive tract inhibition. Open reduction and internal fixation of rib fractures involves multiple ribs. Conventional rib fractures require a large incision to achieve satisfactory exposure. Chest wall muscles, blood vessels and nerves (long thoracic and thoracodorsal nerves) are injured, resulting in a high infection rate of the incision and postoperative dysfunctions, such as limited upper limb, shoulder and back function, and long time numbness on the affected side of the chest. Therefore, the damage of muscles and nerves caused by conventional surgical methods limits the development of such surgical technique. Although the video‑assisted thoracoscopic technique has become a necessary technical means for the treatment of thoracic trauma and has been applied to thoracic exploration and hemostasis, there is no report on the application of open reduction and internal fixation for rib fracture. The difficulty lies in the tightly combined bony thorax and the soft tissue of the chest wall. Therefore, experts have explored a variety of minimally invasive surgical methods for the flail chest. The current status and research progress of minimally invasive surgery for thoracic surgery are reviewed.