Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

ObjectiveTo explore the mechanism by which Buyang Huanwutang regulates the glutathione peroxidase 4 （GPX4）-acyl-CoA synthetase long-chain family member 4 （ACSL4） axis to inhibit ferroptosis and promote neurological functional recovery after spinal cord injury （SCI）. MethodsNinety rats were randomly divided into five groups： sham operation group， model group， low-dose Buyang Huanwutang group （12.5 g·kg^-1）， high-dose Buyang Huanwutang group （25 g·kg^-1）， and Buyang Huanwutang + inhibitor group （25 g·kg^-1 + 5 g·kg^-1 RSL3）. The SCI model was established by using the allen method. Tissue was collected on the 7th and 28th days after operation. Motor function was assessed by using the Basso-Beattie-Bresnahan （BBB） scale. Hematoxylin-eosin （HE）， Nissl， and Luxol fast blue （LFB） staining were performed to observe spinal cord histopathology. Transmission electron microscopy was used to examine mitochondrial ultrastructure. Immunofluorescence staining was used to detect the number of NeuN-positive cells and the fluorescence intensity of myelin basic protein （MBP）， GPX4， and ACSL4. Real-time fluorescent quantitative polymerase chain reaction （Real-time PCR） was used to analyze the mRNA expression of GPX4 and ACSL4. Enzyme linked immunosorbent assay （ELISA） was performed to measure the levels of reactive oxygen species （ROS）， malondialdehyde （MDA）， glutathione （GSH）， and superoxide dismutase （SOD）. Colorimetric assays were used to determine the iron content in spinal cord tissue. ResultsCompared to the sham operation group， the model group exhibited significantly reduced BBB scores （P<0.01）， severe pathological damage in spinal cord tissue， and marked mitochondrial ultrastructural disruption. In addition， the model group showed a decrease in the number of NeuN-positive cells （P<0.01）， reduced fluorescence intensity of MBP and GPX4 （P<0.01）， lower levels of GSH and SOD （P<0.01）， and downregulated mRNA expression of GPX4 （P<0.01）. Moreover， compared to the sham operation group， the model group had elevated levels of ROS， MDA， and tissue iron content （P<0.01）， along with increased fluorescence intensity and mRNA expression of ACSL4 （P<0.01）. Compared with the model group and Buyang Huanwutang + inhibitor group， the Buyang Huanwutang group showed significantly improved BBB scores （P<0.05， P<0.01） and exhibited less severe spinal cord tissue damage， reduced edema and inflammatory cell infiltration， increased neuronal survival， and more intact myelin structures. Additionally， mitochondrial ultrastructure was significantly improved in the Buyang Huanwutang group. Compared to the model group and Buyang Huanwutang + inhibitor group， the Buyang Huanwutang group significantly increased the number of NeuN-positive cells and the fluorescence intensity of MBP （P<0.05， P<0.01）. Furthermore， Buyang Huanwutang significantly increased the fluorescence intensity and mRNA expression of GPX4 （P<0.01） and decreased the fluorescence intensity and mRNA expression of ACSL4 （P<0.01） compared to the model group and Buyang Huanwutang + inhibitor group. Finally， the Buyang Huanwutang group significantly decreased ROS， MDA， and tissue iron content （P<0.01） and significantly increased GSH and SOD levels （P<0.01） compared to the model group and Buyang Huanwutang + inhibitor group. ConclusionBuyang Huanwutang inhibits ferroptosis through the GPX4/ACSL4 axis， reduces secondary neuronal and myelin injury and oxidative stress， and ultimately promotes the recovery of neurological function.

Aim In this study, a mouse model of psoriasis-like lesions induced by 62. 5 mg imiquimod was used to explore the effect and mechanism of Sophorae Flavescentis Radix and Rhizoma Smilacis Glabrae combination for the topical treatment of psoriasis. Methods Firstly, the topical administration of Sophorae Flavescentis Radix and Rhizoma Smilacis Glabrae combination for treating psoriasis in progressive and recurrent stages was evaluated by psoriatic mouse model and HE staining. Secondly, immunohistochemistry was used to study the regulatory effects of Sophorae Flavescentis Radix and Rhizoma Smilacis Glabrae combination on the pivotal pathological mechanism of psoriasis-the positive feedback loop between the abnormal proliferation of keratinocytes and skin immune microenvironment. Finally, metabolomics technology was used to explore whether Sophorae Flavescentis Radix and Rhizoma Smilacis Glabrae combination topically treat psoriasis by regulating inflammation-related metabolism and lipid metabolism pathways. Results The combination of Sophorae Flavescentis Radix and Rhizoma Smilacis Glabrae alleviated psoriasis-like lesions in mice. It effectively relieved the recurrence after the cure of psoriatic lesions in mice, and the efficacy is comparable to that of benweimod. The combination of Sophorae Flavescentis Radix and Rhizoma Smilacis Glabrae inhibited the proliferation of mouse epidermal keratinocytes and reduced the number of T cells in the skin. The potential molecular mechanism was that the combination of Sophorae Flavescentis Radix and Rhizoma Smilacis Glabrae regulated arachidonic acid metabolism, sphin- golipid metabolism, tryptophan metabolism and phenylalanine metabolism. Conclusions The combination of Sophora Flavescens Radix and Rhizoma Smilacis Glabrae can relieve psoriasis-like lesions in mice by inhibiting the proliferation of epidermal keratinocytes and reducing the number of T cells in the skin and regulating metabolism to intervene psoriasis recurrence. This study provides a potential topical drug of psoriasis for relieving psoriasis recurrence.

Aim To explore the effects of Lycium berry seed oil on Nrf2/ARE pathway and oxidative damage in testis of subacute aging rats. Methods Fifty out of 60 male SD rats, aged 8 weeks, were subcutaneously injected with 125 mg • kg"D-galactosidase in the neck for 8 weeks to establish a subacute senescent rat model. The presence of senescent cells was observed using P-galactosidase ((3-gal), while testicular morphology was examined using HE staining. Serum levels of testosterone (testosterone, T), follicle-stimulating hormone ( follicle stimulating hormone, FSH ) , luteinizing hormone ( luteinizing hormone, LH ) , superoxide dis-mutase ( superoxide dismutase, SOD ) , glutathione ( glutathione, GSH) and malondialdehyde ( malondial-dehyde, MDA) were measured through ELISA, and the expressions of factors related to aging, oxidative damage, and the Nrf2/ARE pathway were assessed via immunohistochemical analysis and Western blotting. Results After successfully identifying the model, the morphology of the testis was improved and the intervention of Lycium seed oil led to a down-regulation in the expression of [3-gal and -yH2AX. The serum levels of SOD, GSH, T, and FSH increased while MDA and LH decreased (P 0. 05) . Additionally, there was an up-regulated expression of Nrf2, GCLC, NQOl, and SOD2 proteins in testicular tissue ( P 0. 05 ) and nuclear expression of Nrf2 in sertoli cells. Conclusion Lycium barbarum seed oil may reduce oxidative damage in testes of subacute senescent rats by activating the Nrf2/ARE signaling pathway.

Objective: To explore the effects of Buyang Huanwu decoction (BYHWD) on vascular neogenesis and hemorheological parameters following cervical spinal cord injury (SCI). Methods: An acute cervical SCI model was established using 84 female Sprague–Dawley rats. Functional recovery of the rats was evaluated using the forelimb locomotor scale score, forelimb grip strength test, and Basso-Beattie-Bresnahan score. The animals were subsequently euthanized at days 7 and 28 postoperatively. The gross morphology, neuronal survival, and myelin sheath in the injured area were evaluated using hematoxylin and eosin (HE), Nissl, and luxol fast blue (LFB) staining, respectively. Immunofluorescence staining was used to observe CD31 expression 7 days post-injury. Furthermore, the expression of CD31, neuronal nuclear protein (NeuN), and myelin basic protein (MBP) were evaluated 28 days post-injury. Additionally, vascular endothelial growth factor A (VEGFA) and VEGF receptor-2 (VEGFR-2) expression was evaluated using western blotting. Whole-blood viscosity, plasma viscosity, and red blood cell aggregation were measured using a hemorheometer. Results: From postoperative days 3–28, motor function in the BYHWD group began to recover considerably compared to the SCI group. BYHWD effectively restored spinal cord histopathology. In addition, the number of NeuN-positive cells, and fluorescence intensity of CD31at 7 and 28 days and MBP significantly increased in the BYHWD group compared with the SCI group (all P < .05). Moreover, this decoction significantly upregulated the expression of VEGFA and VEGFR-2 (all P < .05). BYHWD improved the hemorheology results (i.e., except erythrocyte aggregation index in the low-dose group), revealing statistically significant differences compared with the SCI group (all P < .05). Conclusion BYHWD effectively promoted angiogenesis, improved hemorheological parameters, and protected neurons and myelin sheaths, ultimately promoting the recovery of neurological function after cervical SCI in rats. These findings suggest that BYHWD promotes vascular neogenesis through the VEGFA/VEGFR-2 pathway.

Autoimmune hepatitis(AIH)is a type of chronic hepatitis caused by the attack of hepatocytes by the autoimmune system,and with the prolongation of disease course,it may gradually progress to liver cirrhosis and even hepatocellular carcinoma.Although great achievements have been made in the understanding and treatment of AIH,its etiology and pathogenesis still remain unclear.T cells play a crucial role in the development and progression of AIH,and by focusing on follicular helper T cells,this article elaborates on the research advances in follicular helper T cells in AIH,in order to provide new ideas and strategies for the clinical treatment of AIH.

Objective To explore effect of nerve growth factor(NGF)antibody on knee osteoarthritis(KOA)pain model was evaluated by in vitro model.Methods Thirty male SPF rats aged 28-week-old were divided into blank group(10 rats with anesthesia only).The other 20 rats were with monoiodoacetate(MIA)on the right knee joint to establish pain model of OA,and were randomly divided into control group(injected intraperitoneal injection of normal saline)and treatment group(injected anti-NGF)intraperitoneal after successful modeling,and 10 rats in each group.All rats were received retrograde injection of fluorogold(FG)into the right knee joint.Gait was assessed using catwalk gait analysis system before treatment,1 and 2 weeks after treatment.Three weeks after treatment,right dorsal root ganglia(DRG)were excised on L4-L6 level,immunostained for calcitonin gene-related peptide(CGRP),and the number of DRGS was counted.Results In terms of gait analysis using cat track system,duty cycle,swing speed and print area ratio in control and treatment group were significantly reduced compared with blank group(P＜0.05).Compared with control group,duty cycle and swing speed of treatment group were significantly im-proved(P＜0.05),and there was no significant difference in print area ratio between treatment group and blank group(P＞0.05).The number of FG-labeled DRG neurons in control group was significantly higher than that in treatment group and blank group(P＜0.05).The expression of CGRP in control group was up-regulated,and differences were statistically significant compared with treatment group(P＜0.05).Conclusion Intraperitoneal injection of anti-NGF antibody inhibited gait injury and upregulation of CGRP in DRG neurons.The results suggest that anti-nerve growth factor therapy may be of value in treating knee pain.NGF may be an important target for the treatment of knee OA pain.

Gliomas are the most common primary intracranial tumors in adults, among which high-grade glioma patients are characterized by short survival and poor prognosis. The diagnosis, treatment, evaluation of effective treatments, and prognosis prediction of high-grade gliomas are of great significance for improving patient survival. Conventional enhanced magnetic resonance imaging has deficiencies in delineating tumor extent, identifying tumor progression and treatment-related changes. Therefore, there is a broad consensus to incorporate amino acid PET, and ¹⁸F-FET PET inparticular, into the diagnostic and therapeutic process of high-grade gliomas. In this article, we review the new research progress of ¹⁸F-FET PET in the diagnosis and treatment of adult high-grade glioma in recent years.

Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannan-binding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP. Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays. Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05). Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.

The objective of this study was to observe the effect of Astragalus membranaceus on high sugar-induced Caenorhabditis elegans, and to explore its mechanism of action. UPLC-MS method was used to identify the components of Astragalus membranaceus. A high glucose model was established by using Caenorhabditis elegans as a model organism, and the effects of Astragalus membranaceus on body length, body bending, swallowing frequency, and reactive oxygen species (ROS) of the nematode were determined; the effects of Astragalus membranaceus on the expression of mRNA of genes related to the protein skinhead-1 (SKN-1) signaling pathway were examined by using the real-time fluorescence quantitative polymerase chain reaction (PCR). The results showed that compared with the normal group, the nematode body length, body bending, and swallowing frequency expression were significantly reduced and the ROS content in the body was significantly increased in the high glucose state; after the administration of Astragalus membranaceus, the body length, body bending, and swallowing frequency expression were significantly increased, and the ROS content was significantly reduced (P < 0.01). Compared with the normal group, SKN-1, superoxide dismutas-3 (SOD-3), glutathione S-transferase 4 (GST-4), and glutathione S-transferase 7 (GST-7) expression were significantly decreased in Caenorhabditis elegans in the high glucose condition; SKN-1, SOD-3, GST-4, and GST-7 expression were significantly increased after administration of Astragalus membranaceus (P < 0.01). In the present study, we demonstrated that Astragalus membranaceus has an effect on high glucose-induced Caenorhabditis elegans nematodes, and its mechanism of action may be through the modulation of the SKN-1 signaling pathwaym in order to ameliorate the oxidative stress response induced by high glucose.