Seizures in febrile children with SARS-CoV-2 infection: clinical features, short-term follow-up.

BACKGROUND: As the Omicron variant of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) emerges, the neurological manifestations correlated with this epidemic have garnered increasing attention. This study was primarily intended to compare seizures in febrile children with and without SARS-CoV-2 infection and to conduct short-term follow-up of the SARS-CoV-2-infected patients. METHODS: Retrospective analysis of patients admitted to the Children's Hospital of Chongqing Medical University for fever and seizures between October 1 and December 30, 2022. Based on the results of SARS-CoV-2 Reverse Transcription-Polymerase Chain Reaction(RT-PCR) at the time of admission, the patients were divided into a Coronavirus disease 2019(COVID-19) positive group and a COVID-19 negative group. Aside from that, we followed up COVID-19-positive patients for 3 months after their discharge from the hospital. The follow-up included monitoring for post-discharge seizures. RESULTS: Compared with the COVID-19-negative group, the COVID-19-positive group had a higher proportion of seizure duration ≥ 15 min(18.7%VS5.1%;P = 0.001), seizure ≥ 2 time(54.4%VS41.0%; P = 0.024), status epilepticus(15.4%VS5.1%; P = 0.005), and Electroencephalogram (EEG) abnormalities(29.4%VS13.6%; P = 0.016). Among the 161 individuals under follow-up, 21 (13.0%)experienced a recurrence of seizures. CONCLUSIONS: Although the incidence of seizure duration ≥ 15 min, number of seizures ≥ 2 time, and status epilepticus was higher in the COVID-19-positive group, the majority of patients had a favorable prognosis. Nonetheless, patients with COVID-19 who present with seizures and persistent impaired consciousness need to be alerted to serious neurological disorders such as acute necrotizing encephalopathy. Owing to the consideration that some patients may experience a recurrence of seizures within a short period of time, it is paramount to provide guardians with education about the emergency management of seizures and to follow up with patients over time.

Watch out for lung tissue trapped by fractured ribs.

A 52-year-old woman was injured in an accident. Emergency tests showed rib fractures and pleural effusion. However, lung incarceration was found during the thoracic exploration that was not detected in the preoperative images. Although this occurrence is rare, clinicians should be careful of this possible pitfall, which may bring about a poor prognosis after a rib fracture.

Pre-Induced ICD Membrane-Coated Carrier-Free Nanoparticles for the Personalized Lung Cancer Immunotherapy.

Immunotherapy is a required adjuvant method in lung cancer therapy clinically. The single immune adjuvant failed to show the expected clinical therapeutic efficacy due to its rapid drug metabolism and inability to accumulate in the tumor site efficiently. Immunogenic cell death (ICD) is a new anti-tumor strategy combined with immune adjuvants. It can provide tumor-associated antigens, activate dendritic cells, and attract lymphoid T cells into the tumor microenvironment. Here doxorubicin-induced tumor membrane-coated iron (II)-cytosine-phosphate-guanine nanoparticles (DM@NPs) are shown for efficient co-delivery of tumor-associated antigens and adjuvant. Higher expression of ICD-related membrane proteins on the surface of the DM@NPs leads to the enhanced uptake of DM@NPs by dendritic cells (DCs), thereby promoting the DCs maturation and pro-inflammatory cytokines release. DM@NPs can remarkably increase the T cell infiltrations, remodel the tumor immune microenvironment and inhibit tumor progression in vivo. These findings reveal that pre-induced ICD tumor cell membrane-encapsulated nanoparticles can enhance immunotherapy responses and provide an effective biomimetic nanomaterial-based therapeutic strategy for lung cancer.

TRIM15 forms a regulatory loop with the AKT/FOXO1 axis and LASP1 to modulate the sensitivity of HCC cells to TKIs.

For patients with advanced or metastatic Hepatocellular carcinoma (HCC) who are not suitable for surgical resection, systemic therapy has been considered to be the standard treatment. In recent years, a small subset of patients with unresectable HCC have been benefit from tyrosine kinase inhibitors (TKIs), and the overall survival time of these patients is significantly increased. However, all responders ultimately develop resistance to TKI treatment. The tripartite motif (TRIM) family member TRIM15 acts as an E3 ligase to mediate the polyubiquitination of substrates in cells. However, the biological role of TRIM15 in HCC is still an enigma. In our study, our results demonstrated that TRIM15 was abnormally upregulated in liver cancer cells after treated with TKIs and that this upregulation of TRIM15 contributed to TKI resistance in liver cancer cells. Then, we demonstrated that the upregulation of TRIM15 after TKI treatment was mediated by the AKT/FOXO1 axis. Moreover, we demonstrated that TRIM15 induced the nuclear translocation of LASP1 by mediating its K63-linked polyubiquitination, which modulated sensitivity to TKIs by increasing the phosphorylation of AKT and the expression of Snail in liver cancer cells. Collectively, we identified a novel AKT/FOXO1/TRIM15/LASP1 loop in cells, which provided potential candidates for overcoming TKI resistance in HCC.

Novel liver vein deprivation technique that promotes increased residual liver volume (with video): A case report.

BACKGROUND: Inadequate volume of future liver remnant (FLR) is a major challenge for hepatobiliary surgeons treating large or multiple liver tumors. As an alternative to associating liver partition and portal vein ligation (ALPPS) for staged hepatectomy and liver venous deprivation (LVD) using stage 1 interventional radiology for vascular embolization combined with stage 2 open liver resection have been used. CASE SUMMARY: A novel modified LVD technique was performed in a patient with pancreatic neuroendocrine tumor with liver metastases by using stage 1 laparoscopic ligation of the right hepatic vein, right posterior portal vein, and short hepatic veins combined with local excision of three liver metastases in the left hemiliver. The operation was followed three days later by interventional radiology to embolize an anomalous right anterior portal vein to complete LVD. A stage 2 laparoscopic right hemihepatectomy and pancreaticosplenectomy were then carried out. CONCLUSION: The minimally invasive technique promoted a rapid increase, comparable to ALPPS, in volume of the FLR after the stage 1 operation to allow the laparoscopic stage 2 resection to be performed.

Surface structure change properties: Auto-soft bionic fibrous membrane in reducing postoperative adhesion.

Peritoneal adhesion is the most common adverse effect following abdominal surgery or inflammation. The occurrence in clinical trials has been successfully reduced using barriers. However, the shortcomings of frequently used adhesion barriers, such as rapid degradation rate of gel barrier and inadequate operation ability of solid barrier, cannot be ignored. In this study, a fibrous membrane with an ECM-like structure was prepared. The adhesion properties were reduced significantly by changing the surface structure. The fibrous membrane caused less inflammatory response and much less peripheral adhesion and intestinal obstruction compared to the casting film and the commercial film with smooth surface, though with the same components. Because of the auto-soft bionic structure and similarity in the mechanical modulus of the tissues, the fibrous membrane was more flexible when it adhered to the tissues, showed excellent effectiveness and biocompatibility. In addition to the rat and miniature pig models, a randomized, placebo-controlled, and multicenter clinical pilot study with 150 patients confirmed that because of its flexibility, biodegradability, and similarity to mechanical modulus and structure with tissues involved, the fibrous membrane served as a favorable implant for preventing post-operation adhesion.

Tumor associated macrophage and microbe: The potential targets of tumor vaccine delivery.

The occurrence and development of tumors depend on the tumor microenvironment (TME), which is made of various immune cells, activated fibroblasts, basement membrane, capillaries, and extracellular matrix. Tumor associated macrophages (TAMs) and microbes are important components in TME. Tumor cells can recruit and educate TAMs and microbes, and the hijacked TAMs and microbes can promote the progression of tumor reciprocally. Tumor vaccine delivery remodeling TME by targeting TAM and microbes can not only enhance the specificity and immunogenicity of antigens, but also contribute to the regulation of TME. Tumor vaccine design benefits from nanotechnology which is a suitable platform for antigen and adjuvant delivery to catalyze new candidate vaccines applying to clinical therapy at unparalleled speed. In view of the characteristics and mechanisms of TME development, vaccine delivery targeting and breaking the malignant interactions among tumor cells, TAMs, and microbes may serve as a novel strategy for tumor therapy.

PM2.5 induces the distant metastasis of lung adenocarcinoma via promoting the stem cell properties of cancer cells.

Lung cancer is the most common cancer in China and second worldwide, of which the incidence of lung adenocarcinoma is rising. As an independent factor, air pollution has drawn the attention of the public. An increasing body of studies has focused on the effect of PM2.5 on lung adenocarcinoma; however, the mechanism remains unclear. We collected the PM2.5 in two megacities, Beijing (BPM) and Shijiazhuang (SPM), located in the capital of China, and compared the different components and sources of PM2.5 in the two cities. Vehicle emissions are the primary sources of BPM, whereas SPM is industrial emissions. We found that chronic exposure to PM2.5 promotes the tumorigenesis and metastasis of lung adenocarcinoma in patient-derived xenograft (PDX) models, as well as the migration and invasion of lung adenocarcinoma cell lines. SPM has more severe effects in vivo and in vitro. The underlying mechanisms are related to the stem cell properties of cancer cells, the epithelial-mesenchymal transition (EMT) process, and the corresponding miRNAs. It is hopeful to provide a theoretical basis for improving air pollution in China, especially in the capital area, and is of the significance of long-term survival of lung cancer patients.

Tumor hijacks macrophages and microbiota through extracellular vesicles.

The tumor microenvironment (TME) is a biological system with sophisticated constituents. In addition to tumor cells, tumor-associated macrophages (TAMs) and microbiota are also dominant components. The phenotypic and functional changes of TAMs are widely considered to be related to most tumor progressions. The chronic colonization of pathogenic microbes and opportunistic pathogens accounts for the generation and development of tumors. As messengers of cell-to-cell communication, tumor-derived extracellular vesicles (TDEVs) can transfer various malignant factors, regulating physiological and pathological changes in the recipients and affecting TAMs and microbes in the TME. Despite the new insights into tumorigenesis and progress brought by the above factors, the crosstalk among tumor cells, macrophages, and microbiota remain elusive, and few studies have focused on how TDEVs act as an intermediary. We reviewed how tumor cells recruit and domesticate macrophages and microbes through extracellular vehicles and how hijacked macrophages and microbiota interact with tumor-promoting feedback, achieving a reciprocal coexistence under the TME and working together to facilitate tumor progression. It is significant to seek evidence to clarify those specific interactions and reveal therapeutic targets to curb tumor progression and improve prognosis.

Implantation of regenerative complexes in traumatic brain injury canine models enhances the reconstruction of neural networks and motor function recovery.

Rationale: The combination of medical and tissue engineering in neural regeneration studies is a promising field. Collagen, silk fibroin and seed cells are suitable options and have been widely used in the repair of spinal cord injury. In this study, we aimed to determine whether the implantation of a complex fabricated with collagen/silk fibroin (SF) and the human umbilical cord mesenchymal stem cells (hUCMSCs) can promote cerebral cortex repair and motor functional recovery in a canine model of traumatic brain injury (TBI). Methods: A porous scaffold was fabricated with cross-linked collagen and SF. Its physical properties and degeneration rate were measured. The scaffolds were co-cultured with hUCMSCs after which an implantable complex was formed. After complex implantation to a canine model of TBI, the motor evoked potential (MEP) and magnetic resonance imaging (MRI) were used to evaluate the integrity of the cerebral cortex. The neurologic score, motion capture, surface electromyography (sEMG), and vertical ground reaction force (vGRF) were measured in the analysis of motor functions. In vitro analysis of inflammation levels was performed by Elisa while immunohistochemistry was used in track the fate of hUCMSCs. In situ hybridization, transmission electron microscope, and immunofluorescence were used to assess neural and vascular regeneration. Results: Favorable physical properties, suitable degradation rate, and biocompatibility were observed in the collagen/SF scaffolds. The group with complex implantation exhibited the best cerebral cortex integrity and motor functions. The implantation also led to the regeneration of more blood vessels and nerve fibers, less glial fibers, and inflammatory factors. Conclusion: Implantation of this complex enhanced therapy in traumatic brain injury (TBI) through structural repair and functional recovery. These effects exhibit the translational prospects for the clinical application of this complex.

Artificial intelligence assisted display in thoracic surgery: development and possibilities.

In this golden age of rapid development of artificial intelligence (AI), researchers and surgeons realized that AI could contribute to healthcare in all aspects, especially in surgery. The popularity of low-dose computed tomography (LDCT) and the improvement of the video-assisted thoracoscopic surgery (VATS) not only bring opportunities for thoracic surgery but also bring challenges on the way forward. Preoperatively localizing lung nodules precisely, intraoperatively identifying anatomical structures accurately, and avoiding complications requires a visual display of individuals' specific anatomy for surgical simulation and assistance. With the advance of AI-assisted display technologies, including 3D reconstruction/3D printing, virtual reality (VR), augmented reality (AR), and mixed reality (MR), computer tomography (CT) imaging in thoracic surgery has been fully utilized for transforming 2D images to 3D model, which facilitates surgical teaching, planning, and simulation. AI-assisted display based on surgical videos is a new surgical application, which is still in its infancy. Notably, it has potential applications in thoracic surgery education, surgical quality evaluation, intraoperative assistance, and postoperative analysis. In this review, we illustrated the current AI-assisted display applications based on CT in thoracic surgery; focused on the emerging AI applications in thoracic surgery based on surgical videos by reviewing its relevant researches in other surgical fields and anticipate its potential development in thoracic surgery.

3D printing collagen/heparin sulfate scaffolds boost neural network reconstruction and motor function recovery after traumatic brain injury in canine.

Tissue engineering is considered highly promising for the repair of traumatic brain injury (TBI), and accumulating evidence has proved the efficacy of biomaterials and 3D printing. Although collagen is famous for its natural properties, some defects still restrict its potential applications in tissue repair. In this experimental study, we fabricated a kind of scaffold with collagen and heparin sulfate via 3D printing, which possesses favorable physical properties and suitable degradation rate along with satisfactory cytocompatibility. After implantation, the results of motor evoked potentials (MEPs) showed that the latency and amplitude can both be improved in hemiplegic limbs, and the structural integrity of the cerebral cortex and corticospinal tract can be enhanced significantly under magnetic resonance imaging (MRI) evaluation. Additionally, the results of in situ hybridization (ISH) and immunofluorescence staining also revealed the facilitating role of 3D printing collagen/heparin sulfate scaffolds on vascular and neural regeneration. Moreover, the individuals implanted with this kind of scaffold present better gait characteristics and preferable electromyography and myodynamia. In general, 3D printed collagen/heparin sulfate scaffolds have superb performance in both structural repair and functional improvement and may offer a new strategy for the repair of TBI.

A Five-lncRNAs Signature-Derived Risk Score Based on TCGA and CGGA for Glioblastoma: Potential Prospects for Treatment Evaluation and Prognostic Prediction.

Accumulating studies have confirmed the crucial role of long non-coding RNAs (ncRNAs) as favorable biomarkers for cancer diagnosis, therapy, and prognosis prediction. In our recent study, we established a robust model which is based on multi-gene signature to predict the therapeutic efficacy and prognosis in glioblastoma (GBM), based on Chinese Glioma Genome Atlas (CGGA) and The Cancer Genome Atlas (TCGA) databases. lncRNA-seq data of GBM from TCGA and CGGA datasets were used to identify differentially expressed genes (DEGs) compared to normal brain tissues. The DEGs were then used for survival analysis by univariate and multivariate COX regression. Then we established a risk score model, depending on the gene signature of multiple survival-associated DEGs. Subsequently, Kaplan-Meier analysis was used for estimating the prognostic and predictive role of the model. Gene set enrichment analysis (GSEA) was applied to investigate the potential pathways associated to high-risk score by the R package "cluster profile" and Wiki-pathway. And five survival associated lncRNAs of GBM were identified: LNC01545, WDR11-AS1, NDUFA6-DT, FRY-AS1, TBX5-AS1. Then the risk score model was established and shows a desirable function for predicting overall survival (OS) in the GBM patients, which means the high-risk score significantly correlated with lower OS both in TCGA and CGGA cohort. GSEA showed that the high-risk score was enriched with PI3K-Akt, VEGFA-VEGFR2, TGF-beta, Notch, T-Cell pathways. Collectively, the five-lncRNAs signature-derived risk score presented satisfactory efficacies in predicting the therapeutic efficacy and prognosis in GBM and will be significant for guiding therapeutic strategies and research direction for GBM.

Clinical observations on the release of tethered spinal cord in children with intra-operative neurophysiological monitoring: A retrospective study.

To study the utility of neurophysiological monitoring in the micro-surgical treatments on children with Tethered Cord Syndrome (TCS). A total of 100 patients were included in this study. 51 children underwent micro-surgical treatments without neurophysiological monitoring (no monitoring group) from 2004 to 2009, whereas 49 children with neurophysiological monitoring (monitoring group) from 2010 to 2016. Postoperative evaluations demonstrated that more children in monitoring group (39, 80%) achieved total release than no monitoring group (36, 71%). Fewer new complications (9, 18%) were found in children of monitoring group than that of no monitoring group (19, 37%) (χ2 = 4.422, P < 0.05). Additionally, more children in monitoring group (34, 76%) achieved complete recovery or significant improvement than that of no monitoring group (24, 54%) (χ2 = 4.326, P < 0.05). This retrospective study provided the evidence supporting the hypothesis that intra-operative neurophysiological monitoring may better guide the surgical process, reduce the risk of post-operative complications, and improve the recovery of children with TCS.

Three-dimensional bioprinting collagen/silk fibroin scaffold combined with neural stem cells promotes nerve regeneration after spinal cord injury.

Many studies have shown that bio-scaffolds have important value for promoting axonal regeneration of injured spinal cord. Indeed, cell transplantation and bio-scaffold implantation are considered to be effective methods for neural regeneration. This study was designed to fabricate a type of three-dimensional collagen/silk fibroin scaffold (3D-CF) with cavities that simulate the anatomy of normal spinal cord. This scaffold allows cell growth in vitro and in vivo. To observe the effects of combined transplantation of neural stem cells (NSCs) and 3D-CF on the repair of spinal cord injury. Forty Sprague-Dawley rats were divided into four groups: sham (only laminectomy was performed), spinal cord injury (transection injury of T10 spinal cord without any transplantation), 3D-CF (3D scaffold was transplanted into the local injured cavity), and 3D-CF + NSCs (3D scaffold co-cultured with NSCs was transplanted into the local injured cavity. Neuroelectrophysiology, imaging, hematoxylin-eosin staining, argentaffin staining, immunofluorescence staining, and western blot assay were performed. Apart from the sham group, neurological scores were significantly higher in the 3D-CF + NSCs group compared with other groups. Moreover, latency of the 3D-CF + NSCs group was significantly reduced, while the amplitude was significantly increased in motor evoked potential tests. The results of magnetic resonance imaging and diffusion tensor imaging showed that both spinal cord continuity and the filling of injury cavity were the best in the 3D-CF + NSCs group. Moreover, regenerative axons were abundant and glial scarring was reduced in the 3D-CF + NSCs group compared with other groups. These results confirm that implantation of 3D-CF combined with NSCs can promote the repair of injured spinal cord. This study was approved by the Institutional Animal Care and Use Committee of People's Armed Police Force Medical Center in 2017 (approval No. 2017-0007.2).

Voltage-gated sodium channel inhibitor reduces atherosclerosis by modulating monocyte/macrophage subsets and suppressing macrophage proliferation.

Inflammatory monocyte and macrophage subset accumulation during the inflammatory response that drives atherosclerosis can exacerbate the extent of atherosclerosis. It has been demonstrated that voltage-gated sodium channels (VGSCs) can regulate cell bioactivities in monocytes/macrophages. We hypothesized that blockade of mononuclear phagocyte VGSCs was atheroprotective through monocyte/macrophage subset modulation and macrophage proliferation suppression in atherosclerotic lesions. In this experimental study, when VGSCs were knocked down with RNA interference plasmid transfection in mouse peripheral blood monocytes and monocyte-macrophage lineage RAW264.7 cells in vitro, the biological characteristics of proliferation, phagocytosis, and migration in RAW264.7 cells declined. In addition, suppression of LPS-induced M1 polarization and facilitation of IL-4-induced M2 polarization were also observed. In an in vivo study, ApoE knockout (ApoE-/-) mice were fed a standard chow diet (CD) or a western diet (WD). After feeding with phenytoin (PHT), no significant differences were detected in plasma lipids, and the anti-inflammatory phenotypes of both monocytes and macrophages were elevated and proinflammatory phenotypes declined. The local proliferation of macrophages was also distinctly suppressed, along with a significant reduction in atheromatous plaques. In conclusion, blockade of VGSCs in the mononuclear phagocyte system reduced atherosclerotic lesions, which may occur through altering monocyte/macrophage subsets and suppressing macrophage proliferation in atherosclerotic plaques. Blockage of VGSCs may play an important role in cardiovascular protection.

[Effects of Exendin-4 on the differentiation of neural stem cells from subventricular zone of adult mice in vitro].

OBJECTIVE: To study the effect of exendin-4(Ex-4) on the differentiation of neural stem cells(NSCs) in adult mouse subventricular zone(SVZ)and its mechanism . METHODS: NSCs in the SVZ were derived from 5-week C57BL/6J mice and the expression of nestin was detected by immunofluorescence. The cell morphology was observed after the cells treatmed with 100 nmol/L Ex-4 for 14 days.The expressions of nestin and glucagon-like peptide-1 receptor (GLP-1R) were detected by immunofluorescence. GLP-1R was knocked down by using shRNA and the study was divided into four groups: control group, Ex-4 group, GLP-1R knockdown group, GLP-1R knockdown + Ex-4 group. After treatment with 100 nmol/L Ex-4 for 14 d, ß-tublin III and glial fibrillary acidic protein (GFAP) were labeled by immunofluorescence and then the proportion of ß-tublin III positive cells were counted. Western blot was used to detect the activation of cAMP-response element binding protein (CREB) in NSCs. In order to further study the effects of Ex-4 on mitogen-activated protein kinase(MAPK) and phosphatidylinositol 3-hydroxy kinase (PI3K) pathways, the cells were pretreated with MAPK inhibitor U0126 at a concentration of 0.07 µmol/L for 30 min or PI3K inhibitor LY294002 at 50 µmol for 2 h, respectively. The study was divided into six groups: control group, Ex-4 group, U0126 group, U0126 + Ex-4 group, LY294002 group, LY294002 + Ex-4 group. The activation of CREB in each group was detected by Western blot. The experiment was repeated three times independently. RESULTS: NSCs were successfully extracted from SVZ of C57BL/6J mice. Immunofluorescence showed that nestin and GLP-1R were positive in NSCs. Compared with the control group, the proportion of neurons differentiated from Ex-4 group was higher. The percentage of neurons in GLP-1R knockdown + Ex-4 group was basically the same as that in control group (P＜0.01). The positive cells of beta-tublin III showed positive activation of GLP-1R and CREB. Western blot showed that CREB was significantly activated in the Ex-4 group, and knockdown of GLP-1R abolished its activation (P＜0.01). U0126 did not affect Ex-4-mediated CERB activation, and LY294002 significantly reduced Ex-4-mediated CREB activation (P＜0.01). CONCLUSION: Ex-4 promotes the differentiation of NSCs into neurons in SVZ of adult mice through GLP-1R receptor, which may be achieved through PI3K/CREB pathway.

Neurological functional evaluation based on accurate motions in big animals with traumatic brain injury.

An accurate and effective neurological evaluation is indispensable in the treatment and rehabilitation of traumatic brain injury. However, most of the existing evaluation methods in basic research and clinical practice are not objective or intuitive for assessing the neurological function of big animals, and are also difficult to use to qualify the extent of damage and recovery. In the present study, we established a big animal model of traumatic brain injury by impacting the cortical motor region of beagles. At 2 weeks after successful modeling, we detected neurological deficiencies in the animal model using a series of techniques, including three-dimensional motion capture, electromyogram and ground reaction force. These novel technologies may play an increasingly important role in the field of traumatic brain injury diagnosis and rehabilitation in the future. The experimental protocol was approved by the Animal Care and Use Committee of Logistics University of People's Armed Police Force (approval No. 2017-0006.2).

Exendin-4 promotes actin cytoskeleton rearrangement and protects cells from Nogo-A-Δ20 mediated spreading inhibition and growth cone collapse by down-regulating RhoA expression and activation via the PI3K pathway.

Exendin-4 is a protein of the GLP-1 family currently used to treat diabetes. Recently, a greater number of biological properties have been associated with the GLP-1 family. Our data shows that exendin-4 treatment significantly increases the cytoskeleton rearrangement, which leads to an increasingly differentiated phenotype and reduced cell migration. We also found that exendin-4 could prevent SH-SY5Y and PC12 cells from Nogo-A-Δ20 mediated spreading inhibition and neurite collapse. Western blot analysis indicated that exendin-4 treatment both reduced the expression and activation of RhoA via the PI3K signaling pathway. These data suggest that exendin-4 may protect nerve regeneration by preventing the inhibition of Nogo-A via down-regulating RhoA expression and activation.

Establishment of a precise novel brain trauma model in a large animal based on injury of the cerebral motor cortex.

BACKGROUND: Animal models are essential in simulating clinical diseases and facilitating relevant studies. NEW METHOD: We established a precise canine model of traumatic brain injury (TBI) based on cerebral motor cortex injury which was confirmed by neuroimaging, electrophysiology, and a series of motor function assessment methods. Twelve beagles were divided into control, sham, and model groups. The cerebral motor cortex was identified by diffusion tensor imaging (DTI), a simple marker method, and intraoperative electrophysiological measurement. Bony windows were designed by magnetic resonance imaging (MRI) scan and DTI. During the operation, canines in the control group were under general anesthesia. The canines were operated via bony window craniotomy and dura mater opening in the sham group. After opening of the bony window and dura mater, the motor cortex was impacted by a modified electronic cortical contusion impactor (eCCI) in the model group. RESULTS: Postoperative measurements revealed damage to the cerebral motor cortex and functional defects. Comparisons between preoperative and postoperative results demonstrated that the established model was successful. COMPARISON WITH EXISTING METHOD(S): Compared with conventional models, this is the first brain trauma model in large animal that was constructed based on injury to the cerebral motor cortex under the guidance of DTI, a simple marker method, and electrophysiology. CONCLUSION: The method used to establish this model can be standardized to enhance reproducibility and provide a stable and precise large animal model of TBI for clinical and basic research.