A Crucial Role of IL-17 and IFN-γ during Acute Rejection of Peripheral Nerve Xenotransplantation in Mice

Nerve injuries causing segmental loss require nerve grafting. However, autografts and allografts have limitations for clinical use. Peripheral nerve xenotransplantation has become an area of great interest in clinical surgery research as an alternative graft strategy. However, xenotransplant rejection is severe with cellular immunity, and Th1 cells play an important role in the process. To better understand the process of rejection, we used peripheral nerve xenografts from rats to mice and found that mononuclear cells expressing IFN-γ and IL-17 infiltrated around the grafts, and IFN-γ and IL-17 producing CD4+ and CD8+ T cells increased during the process of acute rejection. The changes of IL-4 level had no significant difference between xenotransplanted group and sham control group. The rejection of xenograft was significantly prevented after the treatment of IL-17 and IFN-γ neutralizing antibodies. These data suggest that Th17 cells contribute to the acute rejection process of peripheral nerve xenotransplant in addition to Th1 cells

Microfluidic Manipulation for Biomedical Applications in the Central and Peripheral Nervous Systems

Physical injuries and neurodegenerative diseases often lead to irreversible damage to the organizational structure of the central nervous system (CNS) and peripheral nervous system (PNS), culminating in physiological malfunctions. Investigating these complex and diverse biological processes at the macro and micro levels will help to identify the cellular and molecular mechanisms associated with nerve degeneration and regeneration, thereby providing new options for the development of new therapeutic strategies for the functional recovery of the nervous system. Due to their distinct advantages, modern microfluidic platforms have significant potential for high-throughput cell and organoid cultures in vitro, the synthesis of a variety of tissue engineering scaffolds and drug carriers, and observing the delivery of drugs at the desired speed to the desired location in real time. In this review, we first introduce the types of nerve damage and the repair mechanisms of the CNS and PNS; then, we summarize the development of microfluidic platforms and their application in drug carriers. We also describe a variety of damage models, tissue engineering scaffolds, and drug carriers for nerve injury repair based on the application of microfluidic platforms. Finally, we discuss remaining challenges and future perspectives with regard to the promotion of nerve injury repair based on engineered microfluidic platform technology

Differentiation between the motor and sensory fascicles of the peripheral nerves from adult rats using annexin V-CdTe-conjugated polymer

Background : Until now, no method has been available to rapidly differentiate between the motor and sensory nerve fascicles introperatively. Aim : To establish a method to rapidly differentiate between the sensory and motor fascicles in the peripheral nerves. Material and Methods : Annexin V-CdTe-conjugated polymer was used to stain the sciatic and sural nerve fascicles of adult male Wistar rats for 10, 15, 20, and 30 min. Results : Under a light microscope, the sural nerves and the sensory fascicles of the sciatic were visualized as bright red fluorescence with Annexin V-CdTe-conjugated polymer staining. In contrast, no fluorescence on the motor fascicles of the sciatic nerve could be visualized. Fluorescence intensity was not strong enough to show the nerve fascicles with 10 min of staining; however, the intensity was clearly visible after 15 min of staining. No significant difference in the intensity of staining was observed among samples stained for 15, 20, and 30 min. Conclusions : Our study shows that Annexin V-CdTe-conjugated polymer can differentiate the motor and sensory nerve fascicles of the peripheral nerve rapidly and precisely in vitro. This technique represents a new method for the identification of peripheral nerve fascicles

1.2.5. Synthesis, crystal structure and catalytic activity of 2-methoxycarbonylethyldichlorotin hydroxide

Abstract: 2-methoxycarbonylethyldichlorotin hydroxide, CH3OCOCH2CH2SnCl2(OH) ( 1), has been synthesized by hydrolysis reaction and characterized by elemental analysis, FTIR, 1H NMR spectroscopy, and X-ray single crystal diffraction. Compound  1 is a centrosymmetric dimmer, and the tin atom approximates to octahedral geometry via an intramolecular carbonyl- to-tin coordination and hydroxo-bridging. The compound display high selectivity and good catalysis activity on the transesterification reaction of ethyl acetoacetate with an alcohol. Supporting information: FT-IR, 1H NMR, X-Ray, GC/MS analyses, Cif file.

Peripheral nerve injury repair by electrical stimulation combined with graphene-based scaffolds

Peripheral nerve injury (PNI) is a common clinical problem, which due to poor recovery often leads to limb dysfunction and sensory abnormalities in patients. Tissue-engineered nerve guidance conduits (NGCs) that are designed and fabricated from different materials are the potential alternative to nerve autografts. However, translation of these NGCs from lab to commercial scale has not been well achieved. Complete functional recovery with the aid of NGCs in PNI becomes a topic of general interest in tissue engineering and regeneration medicine. Electrical stimulation (ES) has been widely used for many years as an effective physical method to promote nerve repair in both pre-clinical and clinical settings. Similarly, ES of conductive and electroactive materials with a broad range of electrical properties has been shown to facilitate the guidance of axons and enhance the regeneration. Graphene and its derivatives possess unique physicochemical and biological properties, which make them a promising outlook for the development of synthetic scaffolds or NGCs for PNI repair, especially in combination with ES. Considering the discussion regarding ES for the treatment of PNI must continue into further detail, herein, we focus on the role of ES in PNI repair and the molecular mechanism behind the ES therapy for PNI, providing a summary of recent advances in context of graphene-based scaffolds (GBSs) in combination with ES. Future perspectives and some challenges faced in developing GBSs are also highlighted with the aim of promoting their clinical applications

Reconstruction of the Foot and Ankle Using Pedicled or Free Flaps: Perioperative Flap Survival Analysis

<div><p>Objective</p><p>The purpose of this study is to determine the correlation between non-technical risk factors and the perioperative flap survival rate and to evaluate the choice of skin flap for the reconstruction of foot and ankle.</p><p>Methods</p><p>This was a clinical retrospective study. Nine variables were identified. The Kaplan-Meier method coupled with a log-rank test and a Cox regression model was used to predict the risk factors that influence the perioperative flap survival rate. The relationship between postoperative wound infection and risk factors was also analyzed using a logistic regression model.</p><p>Results</p><p>The overall flap survival rate was 85.42%. The necrosis rates of free flaps and pedicled flaps were 5.26% and 20.69%, respectively. According to the Cox regression model, flap type (hazard ratio [HR] = 2.592; 95% confidence interval [CI] (1.606, 4.184); P < 0.001) and postoperative wound infection (HR = 0.266; 95% CI (0.134, 0.529); P < 0.001) were found to be statistically significant risk factors associated with flap necrosis. Based on the logistic regression model, preoperative wound bed inflammation (odds ratio [OR] = 11.371,95% CI (3.117, 41.478), P < 0.001) was a statistically significant risk factor for postoperative wound infection.</p><p>Conclusion</p><p>Flap type and postoperative wound infection were both independent risk factors influencing the flap survival rate in the foot and ankle. However, postoperative wound infection was a risk factor for the pedicled flap but not for the free flap. Microvascular anastomosis is a major cause of free flap necrosis. To reconstruct complex or wide soft tissue defects of the foot or ankle, free flaps are safer and more reliable than pedicled flaps and should thus be the primary choice.</p></div

ELISA assays of IFN-γ, IL-17 and IL-4 in serum.

<p>Sera from collected blood at each time point (1, 3, 6, 11, 16, and 30 days) from xenotransplanted and sham control mice were used for ELISA analysis. Sera IFN-γ and IL-17 levels in the xenograft group were significantly higher than those in the serum in the control group (p<0.05) at day 1, day 3 and day 6, and decreased to control levels by day 11. There is no significant difference of IL-4 levels between recipients and control group. *, p<0.05; **, p<0.01; *** p<0.001. (We performed this experiment twice).</p

Overall survival.

<p>The outcomes of the univariate analysis of risk factors influencing the perioperative flap survival rate. The univariate analysis was performed using the Kaplan-Meier method coupled with a log-rank test.</p

The results of the 144 skin flaps

<p>The results of the 144 skin flaps</p