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).

It has become an industry consensus that self-assembled nanoparticles (SAN) are formed by molecular recognition of chemical components in traditional Chinese medicine during the decoction process. The insoluble components in the decoction are mostly in the form of nanoparticles, which can improve the problem of poor water solubility. However, the transfer rate of these insoluble components in the decoction is still very low, which limits the efficacy of the drug. This study aimed to refine the traditional decoction self-assembly phenomenon. The self-assembled nanoparticles were constructed by micro-precipitation method (MP-SAN), and characterized by particle size, zeta potential, stability index and morphology. The formation of MP-SAN and alterations in related physicochemical properties were evaluated using modern spectroscopic and thermal analysis techniques. The quality value transmitting pattern of lignan components within the MP-SAN was assessed via high performance liquid chromatography (HPLC). The MP-SAN showed sphere-like structure with uniform morphology, particle size of (245.3 ± 3.2) nm, polydispersity index (PDI) of (0.13 ± 0.03), zeta potential of (-48.9 ± 5.9) mV and stability index (SI) of (86.05% ± 2.27%). Comprehensive analyses using ultraviolet visible spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and other techniques confirmed molecular recognition between the decoction and ethanol extraction, leading to electron rearrangement under the influence of non-covalent bonding. This resulted in the formation of nanoparticles possessing superior thermal stability. As determined by HPLC, the encapsulation rates of the index components in the MP-SAN were all greater than 75% (dehydrodiconiferyl alcohol: 77.00%; herpetolide A: 78.57%; herpetrione: 94.53%), and the transfer rates were all higher than 65% (dehydrodiconiferyl alcohol: 96.01%; herpetolide A: 67.86%; herpetrione: 65.55%), which were 1.34, 1.38 and 4.81 times compared with those of the traditional decoction. In summary, this study successfully constructed the MP-SAN based on micro-precipitation method to achieve high transfer rate and high encapsulation rate of insoluble components in docoction, which provides a pharmaceutics idea for the efficient utilization of pharmacodynamic substance basis of traditional Chinese medicine.

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 evaluate the application value of hydrogel in image guided radiotherapy(IGRT)for prostate cancer(PCa).Methods Eighty PCa patients in the First Affiliated Hospital of Hebei North University from October 2022 to February 2023 were collected.The patients were divided into experiment group injected with hydrogel(n=33)and control group without hydrogel(n=47)by central random system allocation.The acute and advanced radiation proctitis(RP)incidence rate of the two groups were compared.Patients in experimental group were divided into RP group(n=5)and non-RP group(n=28).The independent risk factors leading to RP were analyzed by using logistic regression for PCa patients.Results In experiment group,12.1％(4/33)of the patients developed acute grade Ⅰ RP,and 3.0％(1/33)developed advanced grade Ⅰ RP.In control group,31.9％(15/47)of the patients developed acute grade Ⅰ RP,and 12.8％(6/47)developed acute grade Ⅱ RP;19.1％(9/47)of patients developed advanced grade Ⅰ RP,4.3％(2/47)developed advanced grade Ⅱ RP,and 2.1％(1/47)developed advanced grade Ⅲ RP.The incidence of acute and advanced RP in experiment group was lower than that in control group(P<0.05).The application of hydrogel effectively reduced rectal toxicity.Age,rectal volume,V70 and V78 were independent risk factors for the incidence of RP in Pca patients(P<0.05).The characteristics of hydrogel injection were not related to the incidence of RP for Pca patients.Conclusions Hydrogel can effectively reduce the rectal toxicity for Pca patients in IGRT and has little impact on the overall treatment.Hydrogel has certain clinical application and promotion value.

Objective To systematically evaluate the efficacy of different analgesic methods in re-lieving the pain in hip and femoral shaft fractures patients during spinal anesthesia position by using network meta-analysis.Methods The articals of randomized controlled trials(RCTs)that analgesia was performed in patients with hip and femoral shaft fractures during the spinal anesthesia position placement were retrieved from the following database from the establishment of the database to August 2022,PubMed,the Cochrane Library,Web of Science,EMbase,China Biology Medicine(CBM),CNKI,VIP,and Wanfang databases.Literature screening,data extraction and bias risk assessment were conducted by two researchers separately.Stata 17.0 and RevMan 5.3 software were used for statistical analysis.Results A total of 28 RCTs with 1 773 patients were included.The surface under the cumulative ranking(SUCRA)curve showed that and PENG block(94.4%)had the best effect on reducing the VAS pain score of placement position,followed by FIBcombinedwith IVA(83.8%)and FIB(71.1%),and PENG block(98.2%)had the best effect on reducing VAS pain score during spinal anesthesia,followed by FIB(71.1%)and FNB(55.6%),and PENG block(84.1%)had the best effect on shortening the time of spinal anesthesia operation,followed by FNB(70.7%)and FIB(68.5%),and PENG block(99.1%)had the best effect on improving the quality of positioning,followed by FIB(73.1%)and FNB(52.9%).Conclusion Nerve blocks or the combina-tion with IVA can reduce pain scores during position placement and spinal anesthesia,shorten anesthesia operation time,and improve quality of position placement in patients with hip and femoral shaft fractures.PENG block has the best analgesic effect in patients with hip or femoral shaft fractures during positioning and spinal anesthesia.

AIM: To investigate the clinical value of serum vitamin A(Vit A)and basic fibroblast growth factor(bFGF)levels predicting retinopathy of prematurity(ROP).METHODS: Prospective cohort studies. A total of 411 premature or low birth weight infants with gestational age less than 37 wk or birth weight less than 2 500 g who were delivered in Hainan Branch, Shanghai Children's Medical Center Affiliated to Shanghai Jiao Tong University School of Medicine from January 2020 to December 2022 were selected as subjects. The Vit A and bFGF levels in peripheral blood were detected at 7 d and 35 d after birth, respectively.RESULTS: A total of 392 premature infants or low birth weight infants completed clinical study, including 51 cases in stage 1-2 ROP group, 23 cases in stage 3-5 ROP group and 318 cases in the group without ROP. At 7 d postnatal, the serum Vit A(0.44±0.17 μmol/L)and bFGF(0.53±0.16 ng/L)levels in stage 1-2 ROP group were lower than those in the group without ROP(0.50±0.12 μmol/L and 0.63±0.15 ng/L; all P<0.05). The serum Vit A(0.34±0.18 μmol/L)and bFGF(0.44±0.18 ng/L)levels in stage 3-5 ROP group were lower than those in the group without ROP(P<0.05). The serum Vit A and bFGF levels in stage 3-5 ROP group were lower than those in stage 1-2 ROP group(P<0.05). At 35d postnatal, the serum Vit A(0.33±0.19 μmol/L)and bFGF(0.39±0.19 ng/L)levels in stage 3-5 ROP group were lower than those in stage 1-2 ROP group(0.43±0.16 μmol/L and 0.48±0.17 ng/L; all P<0.05). According to the ROC curve drawn by serum Vit A, the AUC value was 0.853, the maximum Youden index was 0.68, the best sensitivity was 73%, and the best specificity was 95%. According to the ROC curve drawn by serum bFGF, the AUC value was 0.828, the maximum Youden index was 0.58, the best sensitivity was 90%, and the best specificity was 68%. According to the ROC curve drawn by serum Vit A combined with bFGF, the AUC value was 0.917, the maximum Youden index was 0.70, the best sensitivity was 70%, and the best specificity was 100%.CONCLUSION: Serum Vit A and bFGF levels are sensitive and effective indicators for predicting ROP. If the serum Vit A or bFGF levels are lower in premature infants or low birth weight infants, it may indicate the higher probability of ROP and its pathological stages. In addition, the clinica value of serum Vit A combined with bFGF in the diagnosis of ROP is higher than that of Vit A or bFGF alone, and the misdiagnosis rate is reduced.

Objective:To explore the effects of participatory interactive teaching in the clinical internship course of pediatric infectious diseases.Methods:217 undergraduate students of grade 2018 majoring in pediatrics were selected as the experimental group, and 208 undergraduate students of grade 2017 majoring in pediatrics were selected as the control group. The experimental group used the teaching method of BOPPPS combined with case-based learning and team-based learning, while the control group adopted the traditional teaching method. Evaluate the learning effectiveness by comparing the formative evaluation and theoretical exam scores of the two groups , and a questionnaire survey was conducted for the students in the experimental group to investigate teaching feedback. SPSS 19.0 was used to perform the t test for data analysis. Results:The experimental group had significantly better scores than the control group in final theoretical examination [(75.04±9.12) vs. (71.03±9.51), P<0.05] and formative evaluation [(81.03±6.13) vs. (70.02±10.32), P<0.05]. According to the results of the questionnaire survey on teaching satisfaction, the students were satisfied with the interactive participatory teaching method in the four aspects of improving learning interest, improving learning ability, classroom satisfaction level, and course acceptance level. Conclusions:The pragmatic teaching reform in the internship of pediatric infectious diseases is highly accepted by students and beneficial to improving students' clinical thinking ability and comprehensive quality, which is worth further application and promotion.

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.