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.

BACKGROUND:We have successfully established an animal model of small ear pig in southern Yunnan province with internal tension relieving technique combined with autologous Achilles tendon for anterior cruciate ligament reconstruction,and verified the stability and reliability of the model.However,whether internal tension relieving technique can promote the ligamentalization process of autologous Achilles tendon graft has not been studied. OBJECTIVE:To investigate the differences in the process of ligamentalization between conventional reconstruction and internal reduction reconstruction of the anterior cruciate ligament by gross view,histology and electron microscopy. METHODS:Thirty adult female small ear pigs in southern Yunnan province were selected.Anterior cruciate ligament reconstruction was performed on the left knee joint with the ipsilateral knee Achilles tendon(n=30 in the normal group),and anterior cruciate ligament reconstruction was performed on the right knee joint with the ipsilateral knee Achilles tendon combined with the internal relaxation and enhancement system(n=30 in the relaxation group).The autogenous right forelimb was used as the control group;the anterior cruciate ligament was exposed but not severed or surgically treated.At 12,24,and 48 weeks after surgery,10 animals were sacrificed,respectively.The left and right knee joint specimens were taken for gross morphological observation to evaluate the graft morphology.MAS score was used to evaluate the excellent and good rate of the ligament at each time point.Hematoxylin-eosin staining was used to evaluate the degree of ligament graft vascularization.Collagen fibers and nuclear morphology were observed,and nuclear morphology was scored.Ultrastructural remodeling was evaluated by scanning electron microscopy and transmission electron microscopy. RESULTS AND CONCLUSION:(1)The ligament healing shape of the relaxation group was better at various time points after surgery,and the excellent and good rate of MAS score was higher(P<0.05).Moreover,the relaxation group could obtain higher ligament vascularization score(P<0.05).(2)The arrangement of collagen bundles and fiber bundles in the two groups gradually tended to be orderly,and the transverse fiber connections between collagen gradually increased and thickened,suggesting that the strength and shape degree of the grafts were gradually improved,but the ligament remodeling in the relaxation group was always faster than that in the normal group at various time points after surgery.(3)The diameter,distribution density,and arrangement degree of collagen fibers in the relaxation group were better than those in the normal group at all time points,especially in the comparison of collagen fiber diameter between and within the relaxation group(P<0.05).

Based on the interaction between supramolecule of traditional Chinese medicine and enterobacteria, the material basis of Rhei Radix et Rhizoma and Coptidis Rhizoma was explored. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) were used to characterize the morphological differences of Rhubarb single decoction, Coptis single decoction and Rhubarb and Coptis co-decoction. An in vitro antibacterial model (E. coli, E. faecium and B. subtilis) was established to evaluate the damage effect of the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma on enterobacteria. Ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to analyze the changes of chemical components of single decoctions and co-decoctions. The co-decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma was turbid after decocting. The spherical particles of 300-400 nm were observed under SEM, and the co-decoction was more uniform and stable than that of single decoction. The interaction between supramolecules formed after the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma and enterobacteria was significantly different from that of single decoction. In the process of interaction between supramolecules and enterobacteria, the spherical state was maintained, and the medicinal ingredients in Coptidis Rhizoma or Rhei Radix et Rhizoma were blocked, which could effectively alleviate the damage to enterobacteria. This study provided a reference for subsequent studies on the regulation of intestinal flora homeostasis by the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma.

Objective:To investigate the gait characteristics of patients with early Parkinson′s disease (PD) under cognitive dual task, and to provide sensitive kinematic indicators for the early diagnosis, timely treatment and reasonable rehabilitation of PD.Methods:A total of 62 outpatients and inpatients with early non-tremor Parkinson′s disease in Shijingshan Branch of Beijing Chaoyang Hospital Affiliated to Capital Medical University from September 2021 to August 2023 were selected as experimental group (PD group), and 62 healthy controls with comparable age composition ratio were selected as control group. The baseline data, Montreal Cognitive Assessment Scale scores, and the gait assessment scores of the motor part of the Unified Parkinson′s Disease Rating Scale were compared between the 2 groups. The wearable gait analysis device was used to collect the gait parameters of the 2 groups of subjects under single task and dual task, and the foot kinematic characteristics of the patients with early PD were quantified. Independent sample t test and Mann-Whitney U test were used to analyze the gait parameters of the 2 groups. The statistically significant variables were included in Logistic regression analysis to explore the association between gait parameters and PD. Finally, the diagnostic value of the variables was estimated by receiver operating characteristic (ROC) curve analysis. Results:Gait spatio-temporal parameters (per gait cycle): (1) The gait speed of the PD group was slower than that of the control group [(1.01±0.12) m/s vs (1.22±0.18) m/s, t=-7.526] during single task walking. The bipedal support time in the PD group was significantly longer than that in the control group [(0.29±0.05) s vs (0.22±0.06) s, t=6.659]. The differences were both statistically significant (both P<0.001). (2) During dual-task walking, PD patients showed slower gait speed [(0.88±0.11) m/s vs (1.19±0.16) m/s, t=-12.158, P<0.001]. The bipedal support time in the PD group was longer than that in the control group [(0.36±0.05) s vs (0.22±0.05) s, t=12.828, P<0.001]. PD patients had shorter stride length [(109.20±6.21) cm vs (112.77±5.87) cm, t=-3.203, P=0.010]. Stride frequency in the PD group was higher than that in the control group [(114.45±7.10) steps/min vs (110.87±7.16) steps/min, t=2.724, P=0.020]. The single leg support time was longer than that of the control group [(0.49±0.12) s vs (0.45±0.06) s, t=2.643, P=0.020] , and the differences were statistically significant. Gait kinematics parameters: (1) During single task walking, the maximum angle of foot movement in the sagittal plane in the PD group was smaller than that in the control group (17.19°±2.37° vs 19.71°±2.92°, t=-4.691, P<0.001). The minimum angle of movement in the sagittal plane was smaller than that in the control group (-67.08°±4.63° vs -70.10°±3.94°, t=0.395, P=0.001). The minimum horizontal angle of the foot during exercise in the PD group was lower than that in the control group (9.08°±4.02° vs 11.80°±3.60°, t=-3.461, P<0.001). The minimum angle of the foot coronal plane in the PD group was smaller than that in the control group (-10.55°±2.87° vs -12.04°±2.31°, t=2.831, P=0.030; the negative sign only represents the movement direction). The touch angle of the foot in the PD group was significantly lower than that in the control group (11.14°±2.78° vs 12.78°±3.57°, t=-2.779, P=0.030). (2) During dual-task walking, the maximum sagittal angle (15.44°±2.54° vs 18.99°±2.71°, t=-6.673, P<0.05), the minimum angle of sagittal plane (-65.68°±4.73° vs -70.02°±4.04°, t=-4.747, P<0.001; the negative sign only represents the direction of movement), the minimum coronal movement angle (-11.15°± 2.99° vs -13.18°±2.50°, t=3.642, P=0.020), the touch angle (11.01°±3.10° vs 12.83°±4.01°, t=-2.438, P=0.010), the minimum horizontal angle (8.83°±4.04° vs 11.83°±3.63°, t=-3.776, P<0.001), and the change of the angle from the ground (-65.00°±3.54° vs -67.06°±3.61°, t=3.133, P<0.001) in the PD group were all smaller than that in the control group. The differences were all statistically significant. Logistic regression analysis showed that step frequency was positively correlated with PD ( OR=1.124,95% CI 1.040-1.201, P=0.001), minimum angle of coronal plane was positively correlated with PD ( OR=1.501, 95% CI 1.040-2.151, P=0.030). Stride length was negatively correlated with PD ( OR=0.902, 95% CI 0.830-0.978, P=0.010). ROC curve was used to evaluate the diagnostic value of step frequency, stride length and minimum angle of coronal plane. For step frequency, when the maximum Youden index was 0.880, the best cut-off value to distinguish the PD group from the control group was 115.000, the sensitivity was 0.577, the specificity was 0.710, and the area under the curve was 0.656. For the minimum coronal angle, when the maximum Youden index was 0.251, the best cut-off value was -12.575, the sensitivity was 0.728, the specificity was 0.531, and the area under the curve was 0.670. For stride length, when the maximum Youden index was 0, the best cut-off value was 100.91, the sensitivity was 0.950, the specificity was 0.050, and the area under the curve was 0.300. Conclusions:Some gait parameters such as step frequency and minimum angle of coronal plane can be used as kinematic markers to reflect the gait characteristics of early PD, which may be helpful in tracking and evaluating the gait disorder characteristics of early PD patients and predicting the risk of PD. Some gait parameters of PD patients are significantly different from those of healthy people during cognitive-motor dual-task walking.

It has gradually become a consensus in the industry that the traditional Chinese medicine gypsum should be decocted first, but the understanding of decocting method is not completely unified in the works of doctors since ancient times, and there are occasional disputes about whether it is necessary to decocting first. In this study, the phase determination, physical and chemical characterization, qualitative and quantitative analysis of inorganic and organic components of the decoctions of herbal pairs and the whole prescription Maxingshigan decoction with gypsum as the center, and the pre-decoctions and co-decoctions of them were carried out to explore the scientific connotation of the pre-decoctions of gypsum. Results show that decoction phases were different between the co-decoctions and pre-decoctions of licorice-gypsum (Gancao-Shigao, GC-SG), ephedra-gypsum (Mahuang-Shigao, MH-SG) and almond-gypsum (Xingren-Shigao, XR-SG). The results of the micromorphology, particle size and zeta potential of herbal pairs and prescription (Quanfang, QF) showed that the supramolecular particles in pre-decoctions were smaller, more uniform and more stable than the co-decoctions. The results of organic components analysis showed that different cooking methods did not change the organic composition and content. ICP-OES results showed that the content of inorganic components in pre-decoctions was higher than in co-decoctions for the same boiling time of gypsum. The IR results showed that the pre-decoctions had stronger chemical functional group effect than the co-decoctions. To sum up, compared with the co-decoction, the pre-decoction of gypsum has different phase state and chemical composition interaction, and the difference of inorganic composition is an important material basis affecting the change of phase state compared with the co-decoction. It indicates that the material basis of traditional Chinese medicine decoction is indeed different whether gypsum is decocted first or not, which can provide a basis for the clinical application of decocted gypsum.

Licorice-gypsum (gancao-shigao, GC-SG) drug pair was used as the research object, using supramolecular chemistry to explore the scientific connotation of combining herbal medicine GC with insoluble mineral medicine SG in clinical application of traditional Chinese medicine. ① The Tyndall effect, microscopic morphology and particle size of the single and co-decocted of GC and SG were observed, the paste content and conductivity were determined, and the interaction between GC and SG was detected by isothermal titration calorimetry (ITC) and infrared absorption spectroscopy (IR). ② Calcium chloride (CaCl₂), a soluble calcium salt of equal gypsum quality, was used instead of SG with GC for co-decocting to explore the effect of calcium salt content on the water decocting, and the characteristics were combined with the Tyndall effect, microscopic morphology, paste content and conductivity. ITC and IR techniques were used to detect the interaction between the two, and the interaction between them was detected by ITC and IR. The zeta potential and ultraviolet-visible spectrophotometry (UV-vis) of GC-SG and GC-CaCl₂ co-decoction were compared, and the inorganic and organic components in the co-decoction were detected by inductively coupled plasma optical emission spectrometer (ICP-OES) and high performance liquid chromatography (HPLC). The results showed: ① Compared with the liquid phase of single decoction, GC-SG co-decoction had more obvious Tyndall effect, and showed uniform spherical nanoparticles under electron microscope. Physical characterization results such as paste content and conductivity showed that co-decoction promoted the dissolution of each other's components; ITC and IR results showed that there was strong interaction between GC and SG, which preliminatively indicated that GC and SG co-decoction promoted the formation of uniform and stable supramolecular system of traditional Chinese medicine. ② When soluble calcium salt was used to substitute insoluble SG with GC for co-decocting, a stronger but astigmatic light path appeared than single decocting solution, the zeta potential was reduced, and a large number of accumulated polymers were formed. The results of paste content and conductivity showed that the dissolution of the co-decocting component was reduced than the single decocting component. ITC, UV-vis and IR results showed that there was interaction between GC with Ca²⁺ and SG. The formation of polysink indicated that a large amount of soluble calcium salt would destroy the stability of supramolecular Chinese medicine. The results of ICP-OES and HPLC showed that the glycyrrhizic acid (GA) content of the former lower than the latter, which was related to the formation of a large number of polycondensates with the increase of Ca²⁺ concentration and the decrease of the dissolution of GA and other active ingredients. This study indicates that the compatibility of GC and SG can form a uniform and stable supramolecular system of traditional Chinese medicine. Calcium salt, the main component of SG, is taken as the starting point. Excessive soluble Ca²⁺ can promote the aggregation of active ingredients such as GA, so as to reveal the scientific connotation of the compatibility of GC and SG, an insoluble mineral medicine.

Anti-tumor traditional Chinese medicine has a long history of clinic application, in which the star molecules have always been the hotspot of modern drug research, but they are limited by the solubility, stability, targeting, bioactivity or toxicity of the monomer components of traditional Chinese medicine anti-tumor star molecules and other pharmacokinetic problems, which hinders the traditional Chinese medicine anti-tumor star molecules for further clinical translation and application. Currently, the nanosystems prepared by supramolecular technologies such as molecular self-assembly and nanomaterial encapsulation have broader application prospects in improving the anti-tumor effect of active components of traditional Chinese medicine, which has attracted extensive attention from scholars at home and abroad. In this paper, we systematically review the research progress in preparation of supramolecular nano-systems from anti-tumor star molecule of traditional Chinese medicine, and summarize the two major categories and ten small classes of carrier-free and carrier-based supramolecular nanosystems and their research cases, and the future development direction is put forward. The purpose of this paper is to provide reference for the research and clinical transformation of using supramolecular technology to improve the clinical application of anti-tumor star molecule of traditional Chinese medicine.

3ʹ-Hydroxy-4ʹ-methoxy-2-hydroxy-5-bromochalcone (hereinafter referred to as C13) is a novel chalcone derivative obtained in the process of structural modification of DHMMF, the antitumor active compound of Resina Draconis, in our laboratory. In this study, we investigated the effects of C13 on the proliferation and apoptosis of human gastric cancer HGC-27 and AGS cells and its potential mechanism of action. Firstly, through methyl thiazolyl tetrazolium (MTT), colony formation assay, and 5-ethynyl-2'-deoxyuridine (EdU) staining, we found that C13 inhibited the proliferation ability of human gastric cancer HGC-27 and AGS cells. Using flow cytometry and Western blot, it was found that C13 induced apoptosis in human gastric cancer HGC-27 and AGS cells, and up-regulated the protein level of cleaved poly ADP-ribose polymerase (cleaved-PARP). The results of RNA sequencing analysis showed that the Erb-b2 receptor tyrosine kinase 4/phosphoinositide 3-kinases/AKT (ErbB4/PI3K/AKT) signaling pathway may be involved in anti-gastric cancer activity of C13. Finally, the results of immunoblotting assay showed that C13 treatment down-regulated the protein levels of ErbB4 and phospho-ErbB4, as well as down-regulated the phosphorylation levels of PI3K and AKT in human gastric cancer HGC-27 and AGS cells, which verified the results from RNA-seq analysis. In conclusion, C13 inhibited the proliferation and induced apoptosis of human gastric cancer cells, which may be related to the down-regulation of ErbB4/PI3K/AKT signaling pathway. This study may provide a candidate drug for the treatment of gastric cancer.

The compound (E)-1-(4-(3-(5-chloro-6-oxo-3,6-dihydropyridin-1(2H)-yl)-3-oxo-propyl-1-ene-1-yl) phenyl)-3-(4-fluorophenyl) urea (C12), a novel derivative of piperlongumine previously synthesized by our research group, was investigated in this study to examine its effects on human non-small cell lung cancer cell line H1299 in vitro and elucidate its potential mechanism of action. The impact of C12 on the proliferation, migration, and invasion abilities of H1299 cells were assessed using methyl thiazolyl tetrazolium (MTT) assay, wound healing assay, cloning formation assay, and Transwell assay. Flow cytometry was employed to evaluate the influence of C12 on cell cycle progression, reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), and apoptosis induction in H1299 cells. Western blot analysis was conducted to investigate the expression levels of p21, Cyclin B1, CDK1, Bax, Bcl-2, JNK, p-JNK, Erk1/2, p-Erk1/2, p38 and p-p38 proteins for exploring the anti-tumor mechanism underlying C12's actions. The results demonstrated that C12 exerted inhibitory effects on the proliferation, migration, and invasion capacities of H1299 cells in a time-dependent and concentration-dependent manner. Moreover, C12 induced G2/M phase arrest in the cell cycle, reduced MMP levels, elevated ROS production, and triggered apoptotic processes. Flow cytometry analysis revealed that C12 downregulated Cyclin B1 and CDK1 protein expressions, resulting in G2/M phase arrest. C12 also upregulated Bax/Bcl-2 ratio, promoting apoptosis. Furthermore, C12 activated MAPK signaling pathway by enhancing phosphorylation levels of JNK, Erk1/2, and p38 proteins. In conclusion, C12 significantly suppressed proliferation, migration, and invasion capabilities while inducing cell cycle arrest and apoptosis in H1299 cells. These effects may be attributed to activation of the MAPK signaling pathway.

The effect of different concentrations of glycyrrhizic acid (GA) and Zn²⁺ on the self-assembly of metal complexes was investigated by forming metal complexes, and the properties and assembly mechanisms of the formed carrier-free supramolecular hydrogel were characterised. Scanning electron microscopy (SEM) and zeta potential were used to characterise the microscopic morphology and stability of the GA-Zn complex hydrogel, which had spherical-like particles of about 1 μm with good stability; the rheometer was used to detect its materialistic properties, which showed excellent stability, self-healing property and reversibility; through in vitro bacterial inhibition, it was found that the GA-Zn carrier-free supramolecular hydrogel has enhanced bacterial inhibition function after assembly. The hydrogel was also found to possess both anti-inflammatory and antioxidant efficacy when evaluated using LPS and H₂O₂ induced RAW 264.7 cell damage models, respectively. The above results suggest that GA-Zn hydrogel not only has good materialistic properties, but also possesses good antibacterial, anti-inflammatory and antioxidant activities, which has the value of clinical research as a carrier-free multi-functional antimicrobial dressing, and the present study provides a reference for the discovery of novel biomedical materials from active molecules of natural traditional Chinese medicine.