Biodegradable Nerve Guide with Glial Cell Line-Derived Neurotrophic Factor Improves Recovery After Facial Nerve Injury in Rats.

Background: Bioengineered nerve guides with glial cell line-derived neurotrophic factor (GDNF) support recovery after facial nerve injury by acting as regenerative scaffolds. Objective: To compare functional, electrophysiological, and histological outcomes after repair of rat facial nerve transection in control, empty nerve guide, and nerve guide with GDNF conditions. Methods: Rats underwent transection and primary repair of the buccal branch of the facial nerve and were divided into (1) transection and repair only, (2) transection and repair augmented with empty guide, (3) transection and repair augmented with GDNF-guide groups. Weekly measurements of the whisking movements were recorded. At 12 weeks, compound muscle action potentials (CMAPs) at the whisker pad were assessed, and samples were collected for histomorphometric analysis. Results: Rats in GDNF-guide group displayed the earliest peak in normalized whisking amplitude. CMAPs were significantly higher after GDNF-guide placement. Mean fiber surface area of the target muscle, axonal count of the injured branch, and the number of Schwann cells were highest with GDNF guides. Conclusion: The biodegradable nerve guide containing double-walled GDNF microspheres enhanced recovery after facial nerve transection and primary repair.

Totally Laparoscopic Pylorus-Preserving Gastrectomy (TLPPG) is Safe and Effective for Early Gastric Cancer Treatment.

Background: Compared to distal gastrectomy (DG), pylorus-preserving gastrectomy (PPG), a peristaltic function-preserving surgery for early gastric cancer (EGC), is advantageous as it leads to a more improved nutritional status and quality of life (QOL) of patients. In recent years, total laparoscopic PPG (TLPPG), an anastomosis which is performed intracorporeally, has increasingly replaced laparoscopic-assisted PPG (LAPPG) due to its minimal invasiveness. Aim: To evaluate the safety and feasibility of TLPPG in terms of perioperative efficacy. Patients: Three patients underwent TLPPG in the Affiliated Hospital of Changzhi Medical College from September 2021 to March 2022. Methods: Surgical safety analysis: Our three cases (TLPPG group) were compared to data from the CLASS-02 study, which collected data from multiple centers across China for the laparoscopic total gastrectomy (LTG group). The CLASS-02 study provides data from the most invasive type of gastric surgery, providing solid comparative data to our own.Postoperative short-term efficacy analysis: Patient questionnaire responses provided data on postoperative nutritional and QOL status. Results from our three cases were compared to the Japanese multicenter data PGSAS-37 (PGSAS group). Results: There were no complications or deaths occurred during or after operation in our cases. Compared to the PGSAS group, our cases scored lower for abdominal pain, dyspepsia, and weight loss. Conclusion: Although more case information is needed, our findings demonstrate that TLPPG may be a possible and effective treatment for EGC in China, similar to that in Japan.

Facial Nerve Repair: Bioengineering Approaches in Preclinical Models.

Injury to the facial nerve can occur after different etiologies and range from simple transection of the branches to varying degrees of segmental loss. Management depends on the extent of injury and options include primary repair for simple transections and using autografts, allografts, or conduits for larger gaps. Tissue engineering plays an important role to create artificial materials that are able to mimic the nerve itself without extra morbidity in the patients. The use of neurotrophic factors or stem cells inside the conduits or around the repair site is being increasingly studied to enhance neural recovery to a greater extent. Preclinical studies remain the hallmark for development of these novel approaches and translation into clinical practice. This review will focus on preclinical models of repair after facial nerve injury to help researchers establish an appropriate model to quantify recovery and analyze functional outcomes. Different bioengineered materials, including conduits and nerve grafts, will be discussed based on the experimental animals that were used and the defects introduced. Future directions to extend the applications of processed nerve allografts, bioengineered conduits, and cues inside the conduits to induce neural recovery after facial nerve injury will be highlighted. Impact statement Recovery after facial nerve injury is a complex process, which involves different management options such as primary repair or the use of nerve grafts or conduits. Various tissue-engineered approaches are increasingly studied on preclinical models with limited, but promising, translation to the clinical setting. Herein, preclinical models focusing on different recovery methods after facial nerve injury are comprehensively reviewed based on the experimental animals used. The review provides key insights into current developments and future directions on this highly relevant topic to help researchers further expand the field of tissue engineering and facial nerve recovery.