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.

AIM To study the chemical constituents from ethyl acetate fraction of Balanophora harlandii Hook.f.and their tyrosinase inhibitory activity.METHODS Separation and purification were performed using silica gel,MCI,ODS,Sephadex LH-20 and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The monophenolase inhibitory activity was determined by the tyrosinase-catalyzed oxidation of L-tyrosine.RESULTS Twenty-four compounds were isolated and identified as sesamin(1),methyl caffeate(2),quercetin(3),5,7-dihydroxychromanone(4),methyl 3,4-dihydroxybenzoate(5),esculetin(6),kaempferol(7),naringenin(8),pyrogallic acid(9),pinosylvin(10),methyl propionate(11),caffeic acid(12),saccharinol(13),ferulic acid(14),trans-p-hydroxycinnamic acid(15),cinnamic acid(16),vanillic acid(17),vanillin(18),4-hydroxyacetophenone(19),4-hydroxybenzaldehyde(20),apigenin(21),(-)-isolariciresinol(22),(-)-secoisolariciresinol(23)and meso-2,3-di(3′,4′-methylenedioxybenzyl)butane-1,4-diol(24).The IC50 values of compounds 3,5,7,8,19,and 20 ranged from(0.246 5±0.028 3)to(1.278 2±0.021 3)mmol/L.CONCLUSION Compounds 1-9、11、15、17-21、24 are isolated from this plant for the first time,and 1,6,9,17-19,24 are first isolated from genus Balanophora.Compounds 3、5、7、8、19 and 20 have tyrosinase inhibitory activity.

Homo- or heterodimeric compounds that affect dimeric protein function through interaction between monomeric moieties and protein subunits can serve as valuable sources of potent and selective drug candidates. Here, we screened an in-house dimeric natural product collection, and panepocyclinol A (PecA) emerged as a selective and potent STAT3 inhibitor with profound anti-tumor efficacy. Through cross-linking C712/C718 residues in separate STAT3 monomers with two distinct Michael receptors, PecA inhibits STAT3 DNA binding affinity and transcription activity. Molecular dynamics simulation reveals the key conformation changes of STAT3 dimers upon the di-covalent binding with PecA that abolishes its DNA interactions. Furthermore, PecA exhibits high efficacy against anaplastic large T cell lymphoma in vitro and in vivo, especially those with constitutively activated STAT3 or STAT3^Y640F. In summary, our study describes a distinct and effective di-covalent modification for the dimeric compound PecA to disrupt STAT3 function.

Metachromatic leukodystrophy (MLD) is an inherited disease caused by a deficiency of the enzyme arylsulfatase A (ARSA). Lentivirus-modified autologous hematopoietic stem cell gene therapy (HSCGT) has recently been approved for clinical use in pre and early symptomatic children with MLD to increase ARSA activity. Unfortunately, this advanced therapy is not available for most patients with MLD who have progressed to more advanced symptomatic stages at diagnosis. Patients with late-onset juvenile MLD typically present with a slower neurological progression of symptoms and represent a significant burden to the economy and healthcare system, whereas those with early onset infantile MLD die within a few years of symptom onset. We conducted a pilot study to determine the safety and benefit of HSCGT in patients with postsymptomatic juvenile MLD and report preliminary results. The safety profile of HSCGT was favorable in this long-term follow-up over 9 years. The most common adverse events (AEs) within 2 months of HSCGT were related to busulfan conditioning, and all AEs resolved. No HSCGT-related AEs and no evidence of distorted hematopoietic differentiation during long-term follow-up for up to 9.6 years. Importantly, to date, patients have maintained remarkably improved ARSA activity with a stable disease state, including increased Functional Independence Measure (FIM) score and decreased magnetic resonance imaging (MRI) lesion score. This long-term follow-up pilot study suggests that HSCGT is safe and provides clinical benefit to patients with postsymptomatic juvenile MLD.
Humans ; Leukodystrophy, Metachromatic/genetics* ; Pilot Projects ; Genetic Therapy/methods* ; Hematopoietic Stem Cell Transplantation ; Male ; Follow-Up Studies ; Female ; Lentivirus/genetics* ; Child ; Child, Preschool ; Hematopoietic Stem Cells/metabolism* ; Cerebroside-Sulfatase/metabolism* ; Adolescent

High-performance liquid chromatography(HPLC) was used to determine the content of three major components in Citri Reticulatae Semen(CRS), including limonin, nomilin, and obacunone. The chromaticity of the CRS sample during salt processing and stir-frying was measured using a color difference meter. Next, the relationship between the color and content of the salt-processed CRS sample was investigated through correlation analysis. By integrating the oil bath technique for processing simulation with HPLC, the changes in the relative content of nomilin and its transformation products were analyzed, with its structural transformation pattern during processing identified. Additionally, RAW264.7 cells were induced with lipopolysaccharides(LPSs) to establish an inflammatory model, and the anti-inflammatory activity of nomilin and its transformation product, namely obacunone was evaluated. The results indicated that as processing progressed, E~*ab and L~* values showed a downward trend; a~* values exhibited a slow increase over a certain period, followed by no significant changes, and b~* values remained stable with no significant changes over a certain period and then started to decrease. The limonin content remained barely unchanged; the nomilin content decreased, and the obacunone increased significantly. The changing trends in content and color parameters during salt-processing and stir-frying were basically consistent. The content of nomilin and obacunone was significantly correlated with the colorimetric values(L~*, a~*, b~*, and E~*ab), while limonin content showed no significant correlation with these values. By analyzing HPLC patterns of nomylin at different heating temperatures and time, it was found that under conditions of 200-250 ℃ for heating of 5-60 min, the content of nomilin significantly decreased, while the obacunone content increased pronouncedly. The in vitro anti-inflammatory activity results indicated that compared to the model group, the group with a high concentration of nomilin and the groups with varying concentrations of obacunone showed significantly reduced release of nitric oxide(NO)(P<0.01). When both were at the same concentration, obacunone showed better performance in inhibiting NO release. In this study, the obvious correlation between the color and content of major components during the processing of CRS samples was identified, and the dynamic patterns of quality change in CRS samples during processing were revealed. Additionally, the study revealed and confirmed the transformation of nomilin into obacunone during processing, with the in vitro anti-inflammatory activity of obacunone significantly greater than that of nomilin. These findings provided a scientific basis for CRS processing optimization, tablet quality control, and its clinical application.
Mice ; Animals ; Drugs, Chinese Herbal/pharmacology* ; RAW 264.7 Cells ; Limonins/chemistry* ; Chromatography, High Pressure Liquid ; Citrus/chemistry* ; Color ; Benzoxepins/chemistry* ; Anti-Inflammatory Agents/chemistry*

AIM To study the chemical constituents from ethyl acetate fraction of Balanophora harlandii Hook.f.and their tyrosinase inhibitory activity.METHODS Separation and purification were performed using silica gel,MCI,ODS,Sephadex LH-20 and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The monophenolase inhibitory activity was determined by the tyrosinase-catalyzed oxidation of L-tyrosine.RESULTS Twenty-four compounds were isolated and identified as sesamin(1),methyl caffeate(2),quercetin(3),5,7-dihydroxychromanone(4),methyl 3,4-dihydroxybenzoate(5),esculetin(6),kaempferol(7),naringenin(8),pyrogallic acid(9),pinosylvin(10),methyl propionate(11),caffeic acid(12),saccharinol(13),ferulic acid(14),trans-p-hydroxycinnamic acid(15),cinnamic acid(16),vanillic acid(17),vanillin(18),4-hydroxyacetophenone(19),4-hydroxybenzaldehyde(20),apigenin(21),(-)-isolariciresinol(22),(-)-secoisolariciresinol(23)and meso-2,3-di(3′,4′-methylenedioxybenzyl)butane-1,4-diol(24).The IC50 values of compounds 3,5,7,8,19,and 20 ranged from(0.246 5±0.028 3)to(1.278 2±0.021 3)mmol/L.CONCLUSION Compounds 1-9、11、15、17-21、24 are isolated from this plant for the first time,and 1,6,9,17-19,24 are first isolated from genus Balanophora.Compounds 3、5、7、8、19 and 20 have tyrosinase inhibitory activity.

Objective:To explore therapeutic effect of sacubitril valsartan sodium combined with Wenxin granule in the treatment of hypertension complicated with paroxysmal atrial fibrillation(AF)and its effect on cardiac electro-physiological structure.Methods:A total of 116 patients with hypertension and paroxysmal atrial fibrillation treated in our hospital from Oct 2021 to Nov 2022 were consecutively selected.According to random number table,they were divided into Wenxin granule group(received Wenxin granule treatment based on routine antihypertensive ther-apy)and combined treatment group(received sacubitril valsartan sodium combined Wenxin granule therapy based on routine antihypertensive therapy)with 58 cases in each group,and both groups were consecutively treated for six months.Clinical symptom score,AF burden,P wave duration,P wave dispersion,left atrial diameter(LAD),left ventricular end-diastolic diameter(LVEDd)and left ventricular ejection fraction(LVEF)were compared between two groups before and after treatment.Results:After treatment,compared with Wenxin granule group,there were significant reductions in clinical symptom score[(1.66±0.69)scores vs.(1.40±0.53)scores],AF burden[4.43(1.65)％vs.1.62(3.50)％],P wave duration[(112.17±6.46)ms vs.(109.29±8.59)ms],P wave dispersion[(32.47±8.11)ms vs.(29.02±7.49)ms]and LAD[(34.83±3.41)mm vs.(33.40±3.74)mm]in combined treatment group(P＜0.05 or＜0.01).There were no significant difference in LVEDd and LVEF between two groups,P＞0.05 both.Conclusion:Sacubitril valsartan sodium combined with Wenxin granule can significantly im-prove clinical symptoms and atrial fibrillation burden,reduce the susceptibility to atrial fibrillation,and inhibit atrial electrical remodeling and structural remodeling in patients with hypertension complicated with paroxysmal atrial fi-brillation.

Objective: To analyze the efficacy, safety, and long-term prognosis of intermediate-dose cytarabine (Ara-c) regimen in the treatment of children with refractory risk organ involvement Langerhans cell histiocytosis (LCH). Methods: Clinical data of 17 children with multisystem and risk organ involvement LCH who failed the first-line therapy and were treated with intermediate-dose Ara-c (250 mg/m², twice daily) regimen in the Hematology Center, Beijing Children's Hospital from January 2013 to December 2016 were analyzed retrospectively. In addition to the basic treatment of vindesine and dexamethasone, the patients received two regimens: regimen A: the intermediate-dose Ara-c combined with cladribine and regimen B: the intermediate-dose Ara-c alone. The efficacy, safety and prognosis of the two regimens were analyzed. Results: Among all 17 patients, there were 11 males and 6 females, with the diagnosis age of 2.1 (1.6, 2.7) years. Ten children received regimen A, all of them achieved active disease-better (AD-B) after 8 courses of induction therapy. The disease activity scores (DAS) decreased from 5.5 (3.0, 9.0) to 1.0 (0, 2.3). Seven children received regimen B, and 6 of them achieved AD-B after 8 courses of induction therapy. The DAS decreased from 4.0 (2.0, 4.0) to 1.0 (0, 2.0). The follow-up time was 6.2 (4.9,7.2) and 5.2 (3.7,5.8) years in group A and B. The 5-year overall survival rate was 100.0% in both groups, and the 5-year event free survival rate was (88.9±10.5)% and (85.7±13.2)% in group A and B. Grade 3 or 4 myelosuppression was observed in 8 patients in group A and 2 patients in group B. Conclusions: The intermediate-dose Ara-c regimen (with or without cladribine) is effective and safe for patients with refractory high-risk LCH, with a good long-term prognosis.
Male ; Female ; Child ; Humans ; Cytarabine/adverse effects* ; Cladribine/adverse effects* ; Retrospective Studies ; Antineoplastic Combined Chemotherapy Protocols/adverse effects* ; Histiocytosis, Langerhans-Cell/drug therapy* ; Prognosis

Aim To investigate the effects of CPD1, a novel phosphodiesterase 5 inhibitor, on liver pathological phenotype and hepatic stellate cells (HSCs) activation in hepatic fibrosis model mice caused by carbon tetrachloride ( CCl

This study was designed to evaluate the protective effect of CPD1, a novel phosphodiesterase 5 inhibitor, on renal interstitial fibrosis after unilateral renal ischemia-reperfusion injury (UIRI). Male BALB/c mice were subjected to UIRI, and treated with CPD1 once daily (i.g, 5 mg/kg). Contralateral nephrectomy was performed on day 10 after UIRI, and the UIRI kidneys were harvested on day 11. Hematoxylin-eosin (HE), Masson trichrome and Sirius Red staining methods were used to observe the renal tissue structural lesions and fibrosis. Immunohistochemical staining and Western blot were used to detect the expression of proteins related to fibrosis. HE, Sirius Red and Masson trichrome staining showed that CPD1-treated UIRI mice had lower extent of tubular epithelial cell injury and deposition of extracellular matrix (ECM) in renal interstitium compared with those in the fibrotic mouse kidneys. The results from immunohistochemistry and Western blot assay indicated significantly decreased protein expressions of type I collagen, fibronectin, plasminogen activator inhibitor-1 (PAI-1) and α-smooth muscle actin (α-SMA) after CPD1 treatment. In addition, CPD1 dose-dependently inhibited the expression of ECM-related proteins induced by transforming growth factor β1 (TGF-β1) in normal rat kidney interstitial fibroblasts (NRK-49F) and human renal tubular epithelial cell line (HK-2). In summary, the novel PDE inhibitor, CPD1, displays strong protective effects against UIRI and fibrosis by suppressing TGF-β signaling pathway and regulating the balance between ECM synthesis and degradation through PAI-1.
Animals ; Humans ; Male ; Mice ; Rats ; Extracellular Matrix Proteins ; Fibrosis ; Kidney ; Kidney Diseases ; Phosphodiesterase 5 Inhibitors ; Plasminogen Activator Inhibitor 1