Glucose oxidase (GOD) is an oxygen-consuming dehydrogenase that can catalyze the production of gluconic acid hydrogen peroxide from glucose, and its specific mechanism of action makes it promising for applications, while the low catalytic activity and poor thermostability have become the main factors limiting the industrial application of this enzyme. In this study, we used the glucose oxidase AtGOD reported with the best thermostability as the source sequence for phylogenetic analysis to obtain the GOD with excellent performance. Six genes were screened and successfully synthesized for functional validation. Among them, the glucose oxidase AhGODB derived from Aspergillus heteromorphus was expressed in Pichia pastoris and showed better thermostability and catalytic activity, with an optimal temperature of 40 ℃, a specific activity of 112.2 U/mg, and a relative activity of 47% after 5 min of treatment at 70 ℃. To improve its activity and thermal stability, we constructed several mutants by directed evolution combined with rational design. Compared with the original enzyme, the mutant T72R/A153P showcased the optimum temperature increasing from 40 to 50 ℃, the specific activity increasing from 112.2 U/mg to 166.1 U/mg, and the relative activity after treatment at 70 ℃ for 30 min increasing from 0% to 33%. In conclusion, the glucose oxidase mutants obtained in this study have improved catalytic activity and thermostability, and have potential for application.
Glucose Oxidase/chemistry* ; Enzyme Stability ; Aspergillus/genetics* ; Pichia/metabolism* ; Temperature ; Catalysis ; Fungal Proteins/metabolism* ; Hot Temperature

BACKGROUND: The incidence of leptomeningeal metastasis (LM) in patients with advanced non-small cell lung cancer (NSCLC) is increasing gradually. However, it poses therapeutic challenges due to limited effective interventions. Intrathecal Pemetrexed (IP) holds broad application prospects in the therapeutic domain of LM. This study aims to evaluate the efficacy, safety, and optimal combination strategies of IP in NSCLC-LM patients with epidermal growth factor receptor (EGFR) mutation-positive status, with the aim of providing real-world data support for exploring more precise personalized treatment strategies for these patients. METHODS: 104 EGFR-mutated NSCLC-LM patients who received IP treatment at Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School from January 2018 to June 2024 were analyzed retrospectively. Clinical parameters, treatment regimens, and survival outcomes were collected. The overall survival (OS), progression-free survival (PFS), clinical response rate and adverse events (AEs) were evaluated. RESULTS: The cohort demonstrated a median PFS of 9.6 months and OS of 13.0 months with 6-month and 1-year OS rates of 80.8% and 56.5%, respectively. Clinical response was observed in 77.9% of patients. The common AEs were myelosuppression (58.7%) and elevation of hepatic aminotransferases (25.0%). Nine (8.7%) patients experienced grade 4 myelosuppression and recovered to normal after receiving symptomatic treatment. Subgroup analyses revealed prolonged OS in patients with Karnofsky performance status (KPS) ≥60 versus <60 (14.4 vs 9.0 months, P=0.0022) and those receiving Bevacizumab therapy versus not (19.2 vs 10.5 months, P=0.0011). CONCLUSIONS IP exhibits promising efficacy and manageable toxicity in EGFR-mutated NSCLC-LM patients. When combined with Bevacizumab, it exerts synergistic antitumor effects with the potential to further improve clinical outcomes.
Humans ; Pemetrexed/therapeutic use* ; Carcinoma, Non-Small-Cell Lung/pathology* ; Male ; Female ; Middle Aged ; Lung Neoplasms/pathology* ; ErbB Receptors/genetics* ; Aged ; Mutation ; Adult ; Retrospective Studies ; Injections, Spinal ; Meningeal Neoplasms/genetics* ; Treatment Outcome ; Aged, 80 and over

Objective To investigate the role and related mechanisms of exosomes derived from mesenchymal stem cells (MSCs) in radiation-induced lung injury (RILI). Methods Human umbilical cord-derived MSCs were isolated and cultured for the extraction and identification of exosomes. Eighteen male SD rats were randomly divided into Control group, RILI group and RILI + exosomes group (EXO group), with 6 rats in each group. Except for Control group, the other groups received a single X-ray dose of 30 Gy to the right lung. Immediately after irradiation, the EXO group was administered 2 × 10⁹ exosomes/kg via tail vein injection. Control group and RILI group were given the same volume of normal saline. Eight weeks post-irradiation, the rats were sacrificed, lung tissue and peripheral venous blood were collected. HE and Masson staining were employed to observe the pathological and fibrotic changes of lung tissue. The levels of serum inflammatory factors IL-6, IFN-γ, TNF-α, and IL-10 were detected by ELISA. RT-qPCR was used to assess the mRNA levels of IL-1β, IL-6, Cdh1, and Col1a1 in lung tissue. The expression levels of Vimentin and TGF-β1 in lung tissue were measured by immunohistochemical staining. The expression levels of AMPK, p-AMPK, and TGF-β1 in lung tissue were detected by Western blot. Results MSC-derived exosomes were successfully extracted and identified. Compared with RILI group, EXO group showed significantly reduced pathological changes of lung inflammation and collagen deposition. The levels of serum inflammatory factors IL-6, INF-γ, and TNF-α were significantly decreased (P < 0.05), and the level of anti-inflammatory factor IL-10 was significantly increased (P < 0.05). The mRNA levels of IL-1β, IL-6, and Col1a1 in lung tissue were significantly decreased (P < 0.05 or P < 0.01), and the mRNA level of Cdh1 was significantly increased (P < 0.05 or P < 0.01). The levels of Vimentin and TGF-β1 in lung tissue were significantly reduced, while p-AMPK level was significantly up-regulated (P < 0.05). Conclusion Exosomes derived from MSCs may alleviate RILI by inhibiting inflammatory responses and regulating epithelial-mesenchymal transition mediated by AMPK/TGF-β1 signaling pathway.

BACKGROUND:Pinoresinol diglucoside promotes bone formation and bone matrix synthesis and accelerates bone tissue repair.However,the mechanism of action and effects of this compound in osteoblasts need to be further explored. OBJECTIVE:To investigate the effect and mechanism of action of pinoresinol diglucoside on dexamethasone-treated osteoblasts based on the Wnt/β-catenin signaling pathway. METHODS:Different concentrations of dexamethasone groups and pinoresinol diglucoside groups were set to treat osteoblasts for 24 hours,and the optimal intervention concentrations were screened.Osteoblasts were treated with dexamethasone,pinoresinol diglucoside and inhibitor XAV-939.Then,control group,dexamethasone group,XVA-939 group,pinoresinol diglucoside group,pinoresinol diglucoside+XVA-939 group were set up.Cell counting kit-8 assay was used to detect cell activity.Alkaline phosphatase activity and caspase3/7 enzyme activity in cells were detected.Annexin V/PI staining and EdU assay were used to detect cell apoptosis and proliferation.Real-time qPCR and western blot were used to detect the mRNA and protein expression levels of Wnt3a,β-catenin,c-myc,osteocalcin,and type I collagen,respectively. RESULTS AND CONCLUSION:After dexamethasone and pinoresinol diglucoside intervened in osteoblasts for 24 hours,10 μmol/L dexamethasone was found to be the optimal intervention concentration for cell inhibition,and cell proliferation was most pronounced at a concentration of pinoresinol diglucoside of 100 μmol/L.Compared with the dexamethasone group,alkaline phosphatase activity was significantly enhanced(P<0.05)and caspase3/7 enzyme activity was significantly reduced(P<0.05)in the pinoresinol diglucoside group.Annexin V/PI staining and cell proliferation assay by EdU method showed that pinoresinol diglucoside inhibited apoptosis and promoted proliferation of osteoblasts after dexamethasone intervention.The mRNA and protein expression levels of Wnt3a,β-catenin,c-myc,osteocalcin,and type I collagen were significantly higher in the pinoresinol diglucoside group and pinoresinol diglucoside+XVA-939 group compared with the dexamethasone and XVA-939 groups(P<0.05).To conclude,pinoresinol diglucoside can inhibit osteoblast apoptosis after dexamethasone intervention,protect osteoblast activity and promote osteoblast proliferation by activating the Wnt/β-catenin signaling pathway,which may play a role in delaying steroid-induced osteonecrosis of the femoral head.

Objective:To identify and validate secreted effector proteins of Chlamydia psittaci ( C. psittaci) through bioinformatic prediction and experimental verification, and to characterize their subcellular localization in host cells. Methods:Potential effector proteins were predicted using bioinformatics tools. Candidate effectors were fused to β-lactamase through the constructed expression vectors, and these vectors were transformed into C. psittaci. The secretion of these candidate effectors was evaluated by β-lactamase translocation assays. Eukaryotic expression vectors of confirmed effectors were transfected into host cells to determine their intracellular localization patterns. Results:Bioinformatic analysis identified 29 candidate effector proteins. Experimental validation confirmed the secretion of five effectors, with four exhibiting cytoplasmic localization and one displaying nuclear localization in host cells.Conclusion:This study characterizes five novel C. psittaci secreted effector proteins, providing critical insights for investigating the molecular pathogenesis of psittacosis.

Objective:To explore the pathogenic mechanism of a child with Waardenburg syndrome type 4C due to a c. 661_664dup (p.P222Lfs*60) variant of SOX10 gene through in vitro experiments. Methods:A child diagnosed at the Handan First Hospital was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples were collected from the child and his parents. Following extraction of genomic DNA, trio-whole exome sequencing was carried out. Pathogenicity of candidate variant was determined by bioinformatic analysis and reference to the guidelines from the American College of Medical Genetics and Genomics (ACMG). Candidate variant was verified by Sanger sequencing. Expression plasmids of wild-type SOX10 and the c. 661_664dup (p.P222Lfs*60) variant were constructed and transiently transfected into 293T cells to determine the expression at the RNA and protein levels. The 293T cells transiently transfected with the wild-type/mutant SOX10 were treated with 10 μg/mL cycloheximide (CHX) for 0, 4, 8, 24 h, respectively, and the degradation rate of target protein was detected by Western blotting assay. This study has been approved by the Ethics Committe of Handan First Hospital(Ethics No.HDYY-LW-25053). Results:The child was found to harbor a heterozygous c. 661_664dup (p.P222Lfs*60) variant of the SOX10 gene, which was unreported previously. The variant did not significantly alter the expression of SOX10 at the mRNA level but the protein level. After the CHX treatment, the degradation of mutant SOX10 protein had slowed down. Conclusion:The mutant SOX10 may affect the expression of downstream genes by affecting the degradation rate of its protein product.

Diabetic kidney disease (DKD) with increasing global prevalence lacks effective therapeutic targets to halt or reverse its progression. Therapeutic targets supported by causal genetic evidence are more likely to succeed in randomized clinical trials. In this study, we integrated large-scale plasma proteomics, genetic-driven causal inference, and experimental validation to identify prioritized targets for DKD using the UK Biobank (UKB) and FinnGen cohorts. Among 2844 diabetic patients (528 with DKD), we identified 37 targets significantly associated with incident DKD, supported by both observational and causal evidence. Of these, 22% (8/37) of the potential targets are currently under investigation for DKD or other diseases. Our prospective study confirmed that higher levels of three prioritized targets-insulin-like growth factor binding protein 4 (IGFBP4), family with sequence similarity 3 member C (FAM3C), and prostaglandin D2 synthase (PTGDS)-were associated with a 4.35, 3.51, and 3.57-fold increased likelihood of developing DKD, respectively. In addition, population-level protein-altering variants (PAVs) analysis and in vitro experiments cross-validated FAM3C and IGFBP4 as potential new target candidates for DKD, through the classic NLR family pyrin domain containing 3 (NLRP3)-caspase-1-gasdermin D (GSDMD) apoptotic axis. Our results demonstrate that integrating omics data mining with causal inference may be a promising strategy for prioritizing therapeutic targets.

Objective This study aimed to investigate the tumorigenic properties of MMTV-PyMT breast cancer transgenic mice at different ages(in weeks)and the changes in the composition of immune cells in the tumor microenvironment.Methods Eight groups of 4,6,8,10,12,14,16 and 18 weeks of age MMTV-PyMT female mice(FVB mice as the background)and one group of 8 weeks of FVB female mice were prepared for routine blood testing,the pathological changes of the mammary gland and lung metastases were observed by histopathological sections,and the immune cells in blood,spleen,and tumor were analyzed by flow cytometry.Results MMTV-PyMT mice showed adenular ductal lesions at 4～6 weeks of age;the ductal portion expanded to the growth boundary at 8～9 weeks of age,and then gradually broke through the glandular boundary to form early breast cancer at 8～12 weeks of age,and advanced breast cancer at 10～14 weeks of age.At 12 weeks of age,metastases were visible in the lungs of some mice,and at 14 weeks of age,the number of metastases in the lungs increased significantly.As the age of the mice increased,the number of white blood cells,neutrophils,and platelets in their blood increased gradually,while the lymphocytes and erythrocytes showed a gradual downward trend.Flow cytometry showed that with the increase in age,the proportion of T cells in the spleen and tumor gradually decreased,the MDSCs in the blood,spleen,and tumor gradually increased,and the NK cells in the tumor also gradually increased.Conclusions This study analyzed routine blood tests,pathology,and immune cells in the tissues of MMTV-PyMT mouse models of different weeks of age,providing a novel perspective on the dynamic alterations of the tumor immune microenvironment during the malignant progression of breast cancer.

Objective To investigate the effect of circRNA-homeodomain-interacting protein kinase 2(circHIPK2)on angiotensinⅡ(AngⅡ)-induced apoptosis of vascular endothelial cells through the regulation of the miR-7-5p/transcription factor 4(TCF4)axis.Methods Human umbilical vein endothelial cells(HUVECs)were randomly divided into the control,model,negative control cotrans-fection,circHIPK2 knockdown,miR-7-5p overexpression,and circHIPK2 knockdown+miR-7-5p knockdown groups.Except for the control group,all other groups were administered 10 nmol/L Ang Ⅱ to establish a hypertensive injury model.The circHIPK2,miR-7-5p,and TCF4 mRNA expression levels were detected after transfection.Apoptosis,proliferation,mitochondrial membrane potential,reactive oxygen species(ROS),antioxidant enzymes,pro-inflammatory factors,and TCF4 protein expression were assessed.Results Compared with the control group,the expressions of circHIPK2 and TCF4 mRNA,cell apoptosis rate,relative expression of ROS,levels of IL-6,IL-1β,and IL-18,and expressions of Bax and TCF4 protein increased,and cell viability,miR-7-5p mRNA expression,mitochondrial mem-brane potential,activities of superoxide dismutase(SOD)and catalase(CAT),and Bcl-2 protein expression decreased in the model group(P＜0.05).Both circHIPK2 knockdown and miR-7-5p overexpression reversed Ang Ⅱ-induced pathological changes in vascular endothelial cells.miR-7-5p knockdown reduced the effect of circHIPK2 knockdown on pathological cellular changes in the model group.Conclusion circHIPK2 knockdown can weaken TCF4 expression by upregulating miR-7-5p,thereby reducing Ang Ⅱ-induced inflam-mation and oxidative stress in vascular endothelial cells and ultimately inhibiting cell apoptosis.

Diabetic kidney disease(DKD)with increasing global prevalence lacks effective therapeutic targets to halt or reverse its progression.Therapeutic targets supported by causal genetic evidence are more likely to succeed in randomized clinical trials.In this study,we integrated large-scale plasma proteomics,genetic-driven causal inference,and experimental validation to identify prioritized targets for DKD using the UK Biobank(UKB)and FinnGen cohorts.Among 2844 diabetic patients(528 with DKD),we identified 37 targets significantly associated with incident DKD,supported by both observational and causal evi-dence.Of these,22％(8/37)of the potential targets are currently under investigation for DKD or other diseases.Our prospective study confirmed that higher levels of three prioritized targets-insulin-like growth factor binding protein 4(IGFBP4),family with sequence similarity 3 member C(FAM3C),and prostaglandin D2 synthase(PTGDS)—were associated with a 4.35,3.51,and 3.57-fold increased likeli-hood of developing DKD,respectively.In addition,population-level protein-altering variants(PAVs)analysis and in vitro experiments cross-validated FAM3C and IGFBP4 as potential new target candidates for DKD,through the classic NLR family pyrin domain containing 3(NLRP3)-caspase-1-gasdermin D(GSDMD)apoptotic axis.Our results demonstrate that integrating omics data mining with causal inference may be a promising strategy for prioritizing therapeutic targets.