Objective:To explore the short-term efficacy on 3D printing assisted reconstruction of traumatic digit joint defects using rib and costo-osteochondral autograft.Methods:From August 2022 to July 2023, 7 patients with open digit joint defects had undergone emergency primary debridement and fracture fixation in the Department of Orthopaedics, 988th Hospital of the Joint Logistics Support Force of PLA. Patients with more phalangeal defects that could not be aligned were treated with antibiotic bone cement filling in the emergency surgery. In the second stage surgery, bone cement was removed and transfer of rib cartilage graft was performed to reconstruct the digit joint defect. According to a 1∶1 3D printed hand templates, rib cartilage grafts were crafted to the shape of digit joints, and then spliced together the digit joints and bone defects for fixation. Follow-up X-ray examinations were taken and assessment of the healing status of rib and fractures of phalangeal and metacarpophalangeal bones were carried out according to the Paley fracture healing score. At the outpatient follow-up, assessment of transferred joint movement and evaluation of upper limb function were conducted according to the Evaluation Trial Standards of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association. Visual Analogue Scale (VAS) pain scores were evaluated from the affected digits and donor sites.Results:After reconstructive surgery, all 7 patients had primary healing of the wounds of hand. One patient had fat liquefaction at the donor site, and the rest had primary donor site healing. One patient received further surgery for extensor tendon repair after rib cartilage grafting due to the digital extensor tendon injury. All 7 patients were included in postoperative follow-up for 6-11 months, with an average of 9 months. All patients had excellent fracture healing according to the Paley fracture healing score. At the final follow-up, the extension and flexion of the digit joints were found at 40°-80° (average 56.2°) for proximal interphalangeal joints (4 patients), and 10° in extension and 85° in flexion for metacarpophalangeal joint (1 patient). The range of motion of the thumb interphalangeal joint (2 patients) was 20°-35° (average 27.5°). Hand function was assessed according to Evaluation Trial Standards of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association and it was found that 3 patients were in excellent, 3 in good and 1 in fair.Conclusion:This study focused on the treatment of traumatic digit joint defects by transfer of individually crafted rib cartilages in reconstruction of the defected digit joint. It significantly improves the appearance and function of the defected digit joints, especially suitable for the irregular defects of phalangeal bones.

Resection of oral and maxillofacial tumors is often accompanied by the inferior alveolar nerve neurectomy, resulting in abnormal sensation in lower lip. It is generally believed that spontaneous sensory recovery in this nerve injury is difficult. However, during our follow-up, patients with inferior alveolar nerve sacrifice showed different degrees of lower lip sensory recovery. In this study, a prospective cohort study was conducted to demonstrate this phenomenon and analyze the factors influencing sensory recovery. A mental nerve transection model of Thy1-YFP mice and tissue clearing technique were used to explore possible mechanisms in this process. Gene silencing and overexpression experiments were then conducted to detect the changes in cell morphology and molecular markers. In our follow-up, 75% of patients with unilateral inferior alveolar nerve neurectomy had complete sensory recovery of the lower lip 12 months postoperatively. Patients with younger age, malignant tumors, and preservation of ipsilateral buccal and lingual nerves had a shorter recovery time. The buccal nerve collateral sprouting compensation was observed in the lower lip tissue of Thy1-YFP mice. ApoD was demonstrated to be involved in axon growth and peripheral nerve sensory recovery in the animal model. TGF-β inhibited the expression of STAT3 and the transcription of ApoD in Schwann cells through Zfp423. Overall, after sacrificing the inferior alveolar nerve, the collateral compensation of the ipsilateral buccal nerve could innervate the sensation. And this process was regulated by TGF-β-Zfp423-ApoD pathway.
Mice ; Animals ; Lip/innervation* ; Prospective Studies ; Mandibular Nerve/pathology* ; Sensation/physiology* ; Trigeminal Nerve Injuries/pathology*

Objective:To explore the clinical efficacy of Masquelet technique combined with tissue flap transfer in the treatment of infectious composite bone and soft tissue defects in the early and middle stages after internal fixation for tibial fractures.Methods:From October 2017 to November 2020, 12 patients (13 tibial fractures) with infectious bone and soft tissue defects in the early and middle stages after internal fixation were treated in the Department of Orthopaedics, 988th Hospital of the Joint Logistics Support Force of CPLA by two-phased surgery with retaining internal fixation. Phase I procedures were thoroughly removal of the infected lesions and failed screws, preserving internal implants as many as possible, implantation of absorbable calcium sulphate and an antibiotics blended string of beads into the distal and proximal medullary cavity of the fractured bones, filling the bone defect and wrapping the internal implants with antibiotics loaded bone cement. The size of defects was 3.5 cm × 5.0 cm-7.5 cm × 14.5 cm, and the flaps for wound coverage sized 4.0 cm × 5.5 cm-8.0 cm × 15.0 cm. As for the repair of donor site, 8 limbs were sutured directly, 5 limbs could not be closed completely, and the remaining wounds were covered by skin grafting after suture. Based on well control of infection and stable clinical signs, fillings of bone cement were then removed in Phase II surgery, or 6-9 weeks after primary surgery. Autologous cancellous bone pieces or composite allogeneic bone were fully implanted around the induction membrane formed by Masquelet technique, and auxiliary steel plates were implanted for internal fixation of unstable fractures. After discharge, the patients visited the outpatient clinic regularly, and combined with Wechat follow-up. The texture, colour and bone healing were observed. At the last follow-up, the function of the affected limbs were assessed according to Johner-Wruhs evaluation standard.Results:After Phase I surgery, 13 flaps survived smoothly without vascular compromise. The wounds healed in Phase I. Two patients (2 sides) had recurrent infections. Re-debridement was performed and external fixation was applied after removal of internal fixation. After Phase II surgery, all patients were included in 12-26 months of follow-up, with an average of 18 months. Thirteen lower leg fractures healed well, and the time of bone healing was 16-25 (average 19.5) weeks. The Johner Wruhs criteria was used in evaluation of the function of affected limbs, and it was found that 6 patients were in excellent, 5 in good and 2 in fair.Conclusion:It is feasible while preserving the internal implants, to use membrane induction technique (Masquelet technique) combined with flap transfer, together with the absorbable calcium sulphate antibiotic sustained-release beads as a carrier in the phased treatment of infectious bone defects and bone exposure in the early and middle stages after the surgery of tibial internal fixation. It also gives a higher rate of excellence in surgical outcome. This study explores a treatment procedure for traumatic bone infection combined with composite soft tissue defects.

Central nervous system (CNS) injuries, including stroke, traumatic brain injury, and spinal cord injury, are leading causes of long-term disability. It is estimated that more than half of the survivors of severe unilateral injury are unable to use the denervated limb. Previous studies have focused on neuroprotective interventions in the affected hemisphere to limit brain lesions and neurorepair measures to promote recovery. However, the ability to increase plasticity in the injured brain is restricted and difficult to improve. Therefore, over several decades, researchers have been prompted to enhance the compensation by the unaffected hemisphere. Animal experiments have revealed that regrowth of ipsilateral descending fibers from the unaffected hemisphere to denervated motor neurons plays a significant role in the restoration of motor function. In addition, several clinical treatments have been designed to restore ipsilateral motor control, including brain stimulation, nerve transfer surgery, and brain-computer interface systems. Here, we comprehensively review the neural mechanisms as well as translational applications of ipsilateral motor control upon rehabilitation after CNS injuries.
Animals ; Spinal Cord Injuries/therapy* ; Motor Neurons/physiology* ; Brain ; Stroke ; Recovery of Function/physiology*

Objective:To establish a composite functional evaluation system to study the clinical efficacy of single plate and double plate internal fixation in the treatment of C3 distal radius fractures in the elderly.Methods:62 elderly patients (≥ 60 years old) with type C3 distal radius fractures who were admitted to the First Affiliated Hospital of Anhui University of Science and Technology from September 2018 to August 2021 were retrospectively selected and divided into two groups according to the surgical methods: bilateral plate internal fixation treatment group (double plate group) and unilateral plate internal fixation treatment group (single plate group); The preoperative anatomical angle, wrist mobility (flexion and extension) and radius shortening of the two groups were recorded. The anatomical angle, wrist mobility (flexion and extension), clinical Gartland-Werley, DASH Score for Upper Limb Function (DASH) , Wrist Joint Cooney Score and clinical healing time at the 3rd, 6th, 9th and 12th months after operation were followed up. A composite evaluation table was established to comprehensively evaluate the postoperative recovery of patients in the two group.Results:There was no significant difference in anatomical indexes of radius between the two groups before operation (all P>0.05). All anatomical angles and wrist range of motion were within the normal range after operation, and there was no statistical difference between the two groups in each anatomical index of radius within 3 and 6 months after operation (all P>0.05). However, the palmar inclination, ulnar deviation, wrist flexion and dorsiflexion mobility of the double plate group were relatively stable at 9 and 12 months after operation, which were better than those of the single plate group (all P<0.05). The palmar inclination and ulnar deviation of the single plate group increased with time. After operation, the radius shortening of the two groups recovered significantly, and the radius length of the double plate group was maintained better than those of the single plate group for 9 and 12 months (all P<0.05). There was no significant difference in the scores of the two groups within 3 and 6 months after operation (all P>0.05), but the Gartland Werley score, DASH score and Cooney wrist score of the double plate group were significantly better than those of the single plate group at 9 and 12 months after operation (all P<0.05). The clinical healing time of single plate treatment was (14.51±0.88)weeks, the longest was 108 days, while that of double plate treatment was (12.03±1.77)weeks, the longest was 129 days, with statistically significant difference ( P<0.05). There was no significant difference in the incidence of complications between the two groups ( P>0.05). There was no statistically significant difference between the two groups in the final composite evaluation results ( P>0.05), but the total score of the double plate group was smaller than that of the single plate group, with a difference of 39.67 points, indicating that the double plate group still had certain advantages in various scores. Conclusions:According to the composite evaluation system, both single plate and double plate treatment of C3 distal radius fractures in the elderly can achieve satisfactory results. Double plate fixation of distal radius fractures still has a certain significance in maintaining joint stability and improving joint mobility.

Industrial enzymes have become the core "chip" for bio-manufacturing technology. Design and development of novel and efficient enzymes is the key to the development of industrial biotechnology. The scientific basis for the innovative design of industrial catalysts is an in-depth analysis of the structure-activity relationship between enzymes and substrates, as well as their regulatory mechanisms. With the development of bioinformatics and computational technology, the catalytic mechanism of the enzyme can be solved by various calculation methods. Subsequently, the specific regions of the structure can be rationally reconstructed to improve the catalytic performance, which will further promote the industrial application of the target enzyme. Computational simulation and rational design based on the analysis of the structure-activity relationship have become the crucial technology for the preparation of high-efficiency industrial enzymes. This review provides a brief introduction and discussion on various calculation methods and design strategies as well as future trends.
Biocatalysis ; Biotechnology ; Enzymes ; chemistry ; metabolism ; Metabolic Engineering ; Protein Engineering ; Structure-Activity Relationship