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.

This study explores the mechanism of Guben Jiannao Liquid on Alzheimer's disease(AD) by regulating autophagy based on the liver kinase B1(LKB1)/adenosine monophosphate-activated protein kinase(AMPK)/mammalian target of rapamycin(mTOR) pathway. Male SD rats were randomly divided into the blank group, model group, low-dose and high-dose groups of Guben Jiannao Liquid, and rapamycin group, with 10 rats in each group. Except for the blank group, all other groups of rats were injected bilaterally in the hippocampus with β-amyloid(Aβ)_(1-42) to establish the AD model. The low-dose(6.21 g·kg~(-1)) and high-dose(12.42 g·kg~(-1)) groups of Guben Jiannao Liquid and rapamycin group(1 mg·kg~(-1)) were given the corresponding drugs by gavage, and the blank and model groups were given an equal volume of saline by gavage for four weeks. Morris water maze was used to test the learning and memory ability of rats in each group; hematoxylin-eosin(HE) and Nissl staining were used to observe the morphological and quantitative changes of neurons and Nissl bodies in the CA1 region of rat hippocampus; immunohistochemistry was utilized to detect Aβ-positive cell expression in the CA1 region of rat hippocampus; transmission electron microscopy was employed to observe ultrastructural changes in rat hippocampal tissue, and Western blot was used to examine the protein expression levels of LKB1, p-AMPK/AMPK, p-mTOR/mTOR, Beclin1, p62, and LC3-Ⅱ in the hippocampal tissue of the rats. The results showed that compared with those in the blank group, rats in the model group had elevated evasion latency and decreased number of platform transversal and residence time in the platform quadrant. The number of neurons in the hippocampal area was reduced, and the morphology was impaired. The average integral optical density value of Aβ-positive cells was elevated; the expression levels of LKB1, p-AMPK/AMPK, Beclin1, and LC3-Ⅱ were decreased, and the expression levels of p-mTOR/mTOR and p62 were increased. Compared with those in the model group, rats in the low-dose and high-dose groups of Guben Jiannao Liquid had shorter evasion latency, higher number of platform transversal, longer residence time in the platform quadrant, increased number of neurons, decreased expression of Aβ-positive cells and average integral optical density values, and increased number of autophagic lysosomes in hippocampal tissue. The expression levels of LKB1, Beclin1, and LC3-Ⅱ were elevated in the hippocampus of rats in the low-dose group of Guben Jiannao Liquid. The expression levels of LKB1, p-AMPK/AMPK, Beclin1, and LC3-Ⅱ were elevated in the hippocampal tissue of rats in the high-dose group of Guben Jiannao Liquid, and the expression levels of p-mTOR/mTOR and p62 were decreased. The findings suggest that Guben Jiannao Liquid can improve cognitive impairment in AD rats, and its mechanism of action may be related to the activation of the LKB1/AMPK/mTOR signaling pathway and the up-regulation of autophagy level.
Animals ; Alzheimer Disease/physiopathology* ; Male ; TOR Serine-Threonine Kinases/genetics* ; Autophagy/drug effects* ; Rats, Sprague-Dawley ; Protein Serine-Threonine Kinases/genetics* ; AMP-Activated Protein Kinases/genetics* ; Rats ; Drugs, Chinese Herbal/administration & dosage* ; Signal Transduction/drug effects* ; AMP-Activated Protein Kinase Kinases ; Humans ; Hippocampus/metabolism*

This study aims to investigate the effect of Congrong San(CRS) on endoplasmic reticulum stress-induced neuroinflammation in the rat model of Aβ_(1-42)-induced Alzheimer's disease(AD). Sixty male Sprague-Dawley rats(2 months old) were randomized into blank(CON), model(MOD), low-dose Congrong San(L-CRS), medium-dose Congrong San(M-CRS), high-dose Congrong San(H-CRS), and memantine hydrochloride(MJG) groups. The Morris water maze test was carried out to examine the learning and memory abilities of rats in each group. Hematoxylin-eosin staining and Nissl staining were employed to observe the morphology and number of CA1 neurons in the hippocampus of rats in each group. The morphology and structure of the endoplasmic reticulum in the hippocampus were observed by transmission electron microscopy. The immunofluorescence assay was employed to detect the expression of 78 kDa glucose-regulated protein(GRP78) in the hippocampus. Western blot was employed to determine the expression of apoptosis-associated speck-like protein containing a CARD(ASC), cysteinyl aspartate-specific proteinase(caspase-1), interleukin-18(IL-18), interleukin-1β(IL-1β), GRP78, and pathway proteins including protein kinase RNA-like endoplasmic reticulum kinase(PERK), phosphorylated PERK(p-PERK), C/EBP homologous protein(CHOP), and NOD-like receptor pyrin domain-containing protein 3(NLRP3) in the rat hippocampus. Compared with the MOD group, the M-CRS and H-CRS groups showed improved learning and memory abilities, reduced neuron losses in the hippocampus, alleviated endoplasmic reticulum stress, inhibited PERK-CHOP-NLRP3 pathway, and lowered levels of IL-1β, IL-6, and tumor necrosis factor-alpha(TNF-α). The results suggest that CRS can alleviate cognitive impairment and hippocampal neuron damage and reduce neuroinflammation in AD rats by alleviating endoplasmic reticulum stress to inhibit the activation of NLRP3 inflammasomes.
Animals ; Endoplasmic Reticulum Stress/drug effects* ; Male ; Alzheimer Disease/psychology* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Rats, Sprague-Dawley ; Rats ; Inflammasomes/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Cognitive Dysfunction/metabolism* ; Disease Models, Animal ; Hippocampus/drug effects* ; Humans ; Neuroinflammatory Diseases/drug therapy*

This study explores the effect and mechanism of Banxia Xiexin Decoction(BXD) in inhibiting colon cancer progression by reshaping tryptophan metabolism. Balb/c mice were assigned into control, model, low-dose BXD(BXD-L), and high-dose BXD(BXD-H) groups. Except the control group, the other groups were subcutaneously injected with CT26-Luc cells for the modeling of colon cancer, which was followed by the intervention with BXD. Small animal live imaging was employed to monitor tumor growth, and the tumor volume and weight were measured. Hematoxylin-eosin(HE) staining was used to observe the pathological changes in mouse tumors. Immunohistochemistry was used to detect Ki67 expression in tumors. Immunofluorescence and flow cytometry were used to detect the infiltration and number changes of CD3~+/CD8~+ T cells in the tumor tissue. Enzyme-linked immunosorbent assay(ELISA) was employed to measure the levels of interferon-gamma(IFN-γ) and interleukin-2(IL-2) in tumors. Targeted metabolomics was employed to measure the level of tryptophan(Trp) in the serum, and the Trp content in the tumor tissue was measured. Western blot and RT-qPCR were employed to determine the protein and mRNA levels, respectively, of indoleamine 2,3-dioxygenase 1(IDO1), MYC proto-oncogene, and solute carrier family 7 member 5(SLC7A5) in the tumor tissue. Additionally, a co-culture model with CT26 cells and CD8~+ T cells was established in vitro and treated with the BXD-containing serum. The cell counting kit-8(CCK-8) assay was used to examine the viability of CT26 cells. The content of Trp in CT26 cells and CD8~+ T cells, as well as the secretion of IFN-γ and IL-2 by CD8~+ T cells, was measured. RT-qPCR was used to determine the mRNA levels of MYC and SLC7A5 in CT26 cells. The results showed that BXD significantly inhibited the tumor growth, reduced the tumor weight, and decreased the tumor volume in the model mice. In addition, the model mice showed sparse arrangement of tumor cells, varying degrees of patchy necrosis, and downregulated expression of Ki67 in the tumor tissue. BXD elevated the levels of IFN-γ and IL-2 in the tumor tissue, while upregulating the ratio of CD3~+/CD8~+ T cells and lowering the levels of Trp, IDO1, MYC, and SLC7A5. The co-culture experiment showed that BXD-containing serum reduced Trp uptake by CT26 cells, increased Trp content in CD8~+T cells, enhanced IL-2 and IFN-γ secretion of CD8~+T cells, and down-regulated the mRNA levels of MYC and SLC7A5 in CT26 cells. In summary, BXD can inhibit the MYC/SLC7A5 pathway to reshape Trp metabolism and adjust Trp uptake by CD8~+ T cells to enhance the cytotoxicity, thereby inhibiting the development of colon cancer.
Animals ; Tryptophan/metabolism* ; Colonic Neoplasms/pathology* ; Mice ; Drugs, Chinese Herbal/administration & dosage* ; Mice, Inbred BALB C ; Humans ; Cell Line, Tumor ; Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism* ; Female ; Disease Progression ; Cell Proliferation/drug effects* ; Proto-Oncogene Mas ; Male

Radiation-induced injury is a key factor in determining the prognosis of patients undergoing radiotherapy, highlighting the significant clinical importance of developing drugs for radiation prevention and treatment. Especially in oncology, radiation-induced injury remains a pivotal determinant of therapeutic outcomes, because of its direct correlation with normal tissue damage during radiotherapy. Efforts to mitigate or treat such injury are thus paramount in enhancing the overall safety and efficacy of cancer treatment. Novel nanomedicines with prolonged systemic circulation, versatile drug-loading capacities, enhanced tissue retention, and stimuli responsiveness exhibit unique advantages in the treatment and prevention of radiation-induced diseases, as they can be designed based on the specific microenvironment of radiation-damaged tissues, which offers innovative solutions to address the limitations of conventional radioprotectors such as short half-life, poor tissue targeting, and systemic side effects. This review thus aims to provide an overview of recent advance in the design and application of nanomaterials for radiation prevention and treatment. Generally, ionizing radiation damages cells either by inducing DNA double-strand breaks or through the generation of reactive oxygen species (ROS). The resulting oxidative stress would disrupt the structural integrity of cell membranes, proteins, and nucleic acids, leading to apoptosis, chronic inflammation, and systemic effects across multiple systems, including hematopoietic system, gastrointestinal tract, skin, lungs, brain, and heart. Radiation protection strategies focus on scavenging ROS, stimulating cellular repair and regeneration, inducing tissue hypoxia, and inhibiting apoptotic pathways. Recent advances in nanomedicine have introduced novel approaches for targeted and efficient radiation protection and treatment. For radiation-induced hematopoietic injury, nanoparticles can been designed to promote red and white blood cell regeneration while reducing oxidative stress. To address radiation-induced gastrointestinal injuries, nanomaterials enable localized antioxidant delivery and extended intestinal retention, effectively relieving radiation enteritis by scavenging ROS and modulating gut microbiota. For radiation-induced skin injuries, self-assembling peptide hydrogels that mimic the extracellular matrix can serve as effective scaffolds for wound healing. These hydrogels exhibit excellent antioxidant properties, stimulating angiogenesis, and accelerating the recovery of radiation dermatitis. In cases of radiation-induced brain damage, nanoparticles were designed to cross the blood-brain barrier to rescue neuronal damage and protect cognitive function. This review provides an in-depth insight into the mechanisms underlying radiation-induced injuries and highlights how nanomaterial were construtced according to the specific injury. Therefore, nanotechnology endowers durgs with transformative potential for preventing and treating radiation-induced injuries. Despite significant progress in nanomedicine, there are still challenges in long-term biocompatibility, precise targeting of damaged tissues, and scalable manufacturing. In addition, an in-depth understanding of the interactions between nanomaterials and biological systems remains to be covered. Future efforts should focus on optimizing design strategies, enhancing clinical translatability, and ensuring long-term safety, ultimately improving patient outcomes. Besides, expanding research into other radiation-induced diseases, such as radiation-induced ophthalmic disorders and hepatic injuries, may diversify therapeutic options.

OBJECTIVE: To explore the mechanism by which the extract of Semen Ziziphi Spinosae extract promotes bone growth in mice by modulation of the expression of miR-34a-5p in brain tissue. METHODS: Mice were assigned to four experimental groups:a normal control group, a drug administration group (receiving 0.320 mg·g^-1 body weight of Semen Ziziphi Spinosae extract via intragastric administration), a positive control group (receiving 0.013 mg·g^-1 body weight of jujube seed saponin via intragastric administration), and a combination group administration with Semen Ziziphi Spinosae extract plus a 5-hydroxytryptamine 2A receptor (5-HT2AR) agonist (intragastric administration of Semen Ziziphi Spinosae extract combined with intracerebroventricular injection of 8 μg P-MPPF per mice for the final three days of the experiment). Following a 20-day administration period, the effects of the interventions on bone growth, serum growth hormone (GH) levels, and 5-HT2AR expression in brain tissue were evaluated. MicroRNAs (miRNAs) that were differentially expressed in the brain tissues of mice exhibiting bone growth induced by Semen Ziziphi Spinosae extract, as compared to those in normal mice, were identified using a gene chip approach. The interaction between miR-34a-5p and 5-HT2AR was subsequently validated through quantitative reverse transcription polymerase chainreaction (RT-qPCR) and dual-luciferase reporter gene assays. Subsequently, by utilizing the miR-34a-5p inhibitor group and mimics group, along with the normal control group, the drug administration group, the positive control group, and the drug administration combined with miR-34a-5p inhibitor group, the variations in 5-HT2AR expression in mouse brain tissue across all groups were examined, and the binding activity of 5-hydroxytryptamine (5-HT) to the 5-hydroxytryptamine 1A receptor (5-HT1AR) in mice was assessed. RESULTS: The body lengths of the normal control group and the drug administration group were(8.9±0.3) and(10.4±0.4) cm;femur lengths were (8.5±0.3) and (9.1±0.5) mm;tibia lengths were (10.7±0.3) and (11.2±0.4) mm, respectively. The contents of GH levels were (58.6±8.2) and (72.9±6.1) ng·ml-1;and the contents of 5-HT2AR were (32.0±5.0) and (21.9± 5.5) ng·ml-1, respectively. Compared with the normal control group, the drug administration group promoted the growth of body length, femur, and tibia in mice, and increased GH secretion, showing statistically significant differences (P<0.05). Additionally, it significantly reduced the content of 5-HT2AR in brain tissue, with statistical significance (P<0.01). The gene chip analysis identified a total of 16 differentially expressed miRNAs, of which 13 were up-regulated and 3 were down-regulated. Bioinformatics analysis predicted that the up-regulated miR-34a-5p could regulate the expression of 5-HT2AR, a prediction that was confirmed through a dual-luciferase reporter gene assay, demonstrating a direct regulatory interaction between the two. Furthermore, in vivo experiments in mice revealed that overexpression and silencing of miR-34a-5p resulted in corresponding changes in the expression levels of 5-HT2AR in brain tissues/cells, as well as in the binding activity between 5-HT and 5-HT1AR. CONCLUSION The Semen Ziziphi Spinosae extract promotes animal bone growth by enhancing miR-34a-5p expression in brain tissue, downregulating the expression level of 5-HT2AR, improving the binding activity between 5-HT and 5-HT1AR, and extending slow-wave sleep duration, thereby stimulating GH secretion.
Animals ; MicroRNAs/metabolism* ; Mice ; Male ; Brain/metabolism* ; Ziziphus/chemistry* ; Bone Development/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Plant Extracts/pharmacology*

PURPOSE: Septic shock is associated with high mortality and poor outcomes among sepsis patients with coagulopathy. Although traditional statistical methods or machine learning (ML) algorithms have been proposed to predict septic shock, these potential approaches have never been systematically compared. The present work aimed to develop and compare models to predict septic shock among patients with sepsis. METHODS: It is a retrospective cohort study based on 484 patients with sepsis who were admitted to our intensive care units between May 2018 and November 2022. Patients from the 908th Hospital of Chinese PLA Logistical Support Force and Nanchang Hongdu Hospital of Traditional Chinese Medicine were respectively allocated to training (n=311) and validation (n=173) sets. All clinical and laboratory data of sepsis patients characterized by comprehensive coagulation indexes were collected. We developed 5 models based on ML algorithms and 1 model based on a traditional statistical method to predict septic shock in the training cohort. The performance of all models was assessed using the area under the receiver operating characteristic curve and calibration plots. Decision curve analysis was used to evaluate the net benefit of the models. The validation set was applied to verify the predictive accuracy of the models. This study also used Shapley additive explanations method to assess variable importance and explain the prediction made by a ML algorithm. RESULTS: Among all patients, 37.2% experienced septic shock. The characteristic curves of the 6 models ranged from 0.833 to 0.962 and 0.630 to 0.744 in the training and validation sets, respectively. The model with the best prediction performance was based on the support vector machine (SVM) algorithm, which was constructed by age, tissue plasminogen activator-inhibitor complex, prothrombin time, international normalized ratio, white blood cells, and platelet counts. The SVM model showed good calibration and discrimination and a greater net benefit in decision curve analysis. CONCLUSION The SVM algorithm may be superior to other ML and traditional statistical algorithms for predicting septic shock. Physicians can better understand the reliability of the predictive model by Shapley additive explanations value analysis.
Humans ; Shock, Septic/blood* ; Machine Learning ; Male ; Female ; Retrospective Studies ; Middle Aged ; Aged ; Sepsis/complications* ; ROC Curve ; Cohort Studies ; Adult ; Intensive Care Units ; Algorithms ; Blood Coagulation ; Critical Illness

PURPOSE: The rate of complications among patients undergoing surgery has increased due to infection with SARS-CoV-2 and other variants of concern. However, Omicron has shown decreased pathogenicity, raising questions about the risk of postoperative complications among patients who are infected with this variant. This study aimed to investigate complications and related factors among patients with recent Omicron infection prior to undergoing orthopedic surgery. METHODS: A historical control study was conducted. Data were collected from all patients who underwent surgery during 2 distinct periods: (1) between Dec 12, 2022 and Jan 31, 2023 (COVID-19 positive group), (2) between Dec 12, 2021 and Jan 31, 2022 (COVID-19 negative control group). The patients were at least 18 years old. Patients who received conservative treatment after admission or had high-risk diseases or special circumstances (use of anticoagulants before surgery) were excluded from the study. The study outcomes were the total complication rate and related factors. Binary logistic regression analysis was used to identify related factors, and odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the impact of COVID-19 infection on complications. RESULTS: In the analysis, a total of 847 patients who underwent surgery were included, with 275 of these patients testing positive for COVID-19 and 572 testing negative. The COVID-19-positive group had a significantly higher rate of total complications (11.27%) than the control group (4.90%, p < 0.001). After adjusting for relevant factors, the OR was 3.08 (95% CI: 1.45-6.53). Patients who were diagnosed with COVID-19 at 3-4 weeks (OR = 0.20 (95% CI: 0.06-0.59), p = 0.005), 5-6 weeks (OR = 0.16 (95% CI: 0.04-0.59), p = 0.010), or ≥7 weeks (OR = 0.26 (95% CI: 0.06-1.02), p = 0.069) prior to surgery had a lower risk of complications than those who were diagnosed at 0-2 weeks prior to surgery. Seven factors (age, indications for surgery, time of operation, time of COVID-19 diagnosis prior to surgery, C-reactive protein levels, alanine transaminase levels, and aspartate aminotransferase levels) were found to be associated with complications; thus, these factors were used to create a nomogram. CONCLUSION Omicron continues to be a significant factor in the incidence of postoperative complications among patients undergoing orthopedic surgery. By identifying the factors associated with these complications, we can determine the optimal surgical timing, provide more accurate prognostic information, and offer appropriate consultation for orthopedic surgery patients who have been infected with Omicron.
Humans ; COVID-19/complications* ; Male ; Female ; Middle Aged ; Postoperative Complications/epidemiology* ; SARS-CoV-2 ; Orthopedic Procedures/adverse effects* ; Aged ; Nomograms ; Adult ; Retrospective Studies ; Risk Factors

BACKGROUND: Recent studies have shown that sodium-glucose cotransporters-2 (SGLT2) inhibitors significantly improve major adverse cardiovascular events in heart failure with preserved ejection fraction (HFpEF) patients, but the exact mechanism is unknown. Ferritinophagy is a special form of selective autophagy that participates in ferroptosis. In this study, we aimed to investigate whether ferritinophagy was activated during the occurrence of HFpEF, and whether canagliflozin (CANA) could inhibite ferritinophagy. METHODS: We reared Dahl salt-sensitive (DSS) rats on a high-salt diet to construct a hypertensive HFpEF model, and simultaneously administered CANA intervention. Then we detected indicators related to ferritinophagy. RESULTS: The expression of nuclear receptor coactivator 4 (NCOA4), as well as microtubule-associated proteins light chain 3 (LC3), Bcl-2 interacting protein 1 (Beclin-1) and p62, were upregulated in HFpEF rats, accompanied by the downregulation of ferritin heavy chain 1 (FTH1), upregulation of mitochondrial iron transporter sideroflexin1 (SFXN1) and increased reactive oxygen species (ROS) production. Above changes were diminished by CANA. CONCLUSION Ferritinophagy is activated in HFpEF rats and then inhibited by CANA, leading to HFpEF benefits. The inhibition of ferritinophagy could provide new prospective targets for the prevention and treatment of HFpEF, and provide new ideas for investigating the mechanism of cardiovascular benefit of SGLT2 inhibitors.