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.

OBJECTIVE To investigate the intervention effect of kushenol F （KSC-F） on ulcerative colitis （UC） mice. METHODS Totally 30 male C57BL/6J mice were randomly divided into the normal group， model group， positive drug group （sulfasalazine， 703 mg/kg）， KSC-F 50 mg/kg group （KSC-F50 group）， and KSC-F 100 mg/kg group （KSC-F100 group）， with 6 mice in each group. Except for the normal group， the mice in the remaining groups were given 3% dextran sulfate sodium solution continuously for 7 days to induce UC model. Concurrently， administration groups received corresponding drug solution intragastrically， once a day， for 10 consecutive days. During the experiment， the changes in body weight and bowel movements of the mice were observed. Disease activity index scoring was performed after the last administration. The histopathological morphology of colonic tissue was examined. The levels of inflammatory factors in the serum and colon tissue were measured. Additionally， the mRNA expression of inflammatory factors， and the protein expressions of inflammation-related proteins [interleukin-1β （IL-1β）， forkhead box O1（FOXO1）， phosphoinositide 3-kinase（PI3K）， phosphorylated PI3K（p-PI3K）， p38 mitogen-activated protein kinase（p38 MAPK）， phosphorylated p38 MAPK（p-p38 MPAK） and phosphorylated protein kinase B（p- Akt）] were determined in colonic tissue. RESULTS KSC-F could alleviate weight loss and colonic tissue damage in UC mice. KSC- F reduced the levels of IL-1β， IL-6， IL-8 and tumor necrosis factor-α （TNF-α） in serum， as well as IL-1β， IL-6， IL-17 and TNF- α in colonic tissue to varying degrees and increased the levels of IL-10 in both serum and colonic tissue （P＜0.05 or P＜0.01）. Moreover， KSC-F decreased the expression levels of IL-1β， IL-17 and TNF-α mRNA， as well as p-PI3K， p-p38 MAPK， and p- Akt proteins in colonic tissue to varying degrees， and increased the expression levels of IL-10 mRNA and FOXO1 protein in colonic tissue （P＜0.05 or P＜0.01）. CONCLUSIONS KSC-F effectively alleviates UC symptoms in mice by inhibiting PI3K， Akt and p38 MAPK activation， mitigating the release of pro-inflammatory factors such as IL-1β， IL-6， TNF- α，promoting the anti-inflammatory factor IL-10 secretion， and reducing inflammation-induced colonic tissue damage.

Objective To explore the diagnosis of clinically suspicious von Willebrand disease(vWD)in a family and its pathogene-sis.Methods The pedigree information and the biological specimen were collected from the clinically suspected VWD patient and her family members(4 persons in total)in Peking University First Hospital.The levels of platelet count(PLT),activated partial thrombo-plastin time(APTT),vWF antigen(vWF:Ag),vWF activity(vWF:Ac)and FⅧ activity(FⅧ:C)were detected,and vWF risto-cetin cofactor(vWF:RCo)assay,ristocetin-induced platelet aggregation assay(RIPA)and vWF collagen binding(vWF:CB)assay were performed for phenotype diagnosis.The peripheral blood genomic DNAs were extracted from the proband and her family members to perform whole-exome sequencing for identifying the mutation of vWF gene,The mutation site was analyzed by using bioinformation tools to explore the pathogenesis of the proband.Results The APTT of proband(m 1)was slightly prolonged and her vWF:Ag,vWF:Ac,vWF:RCo and vWF:CB were significantly decreased.There was no obvious aggregation in RIPA assay(1.0 mg/mL and 1.25 mg/mL).In her father(Ⅱ3),APTT,FⅧ:C,vWF:Ag,vWF:Ac and vWF:CB were normal,but vWF:RCo was slightly decreased.In her mother(Ⅱ4),APTT,FⅧ:C,vWF:Ag,vWF:RCo and vWF:CB were all normal,but vWF:Ac significantly decreased.In her brother(Ⅲ2),APTT and FⅧ:C were normal,but vWF:Ag,vWF:Ac,vWF:RCo and vWF:CB were reduced to varying degrees.In all the family members(father,mother and brpther),no apparent aggregation in RIPA(1.0 mg/mL)was shown.Genetic analysis showed that the proband(Ⅲ1)carried a compound heterozygous mutation of vWF gene c.7288-9T＞G and c.1117C＞T,her father(Ⅱ3)carried vWF gene c.7288-9T＞G heterozygous mutation,and vWF gene c.1117C＞T heterozygous mutation was presented in both mother(Ⅱ4)and brother(Ⅲ2).Conclusion According to the results of laboratory tests,the proband was diagnosed as type 2A vWD.The hetero-zygous mutation in vWF gene c.1117C＞T and c.7288-9T＞G may be the molecular mechanism leading to type 2A vWD in the proband.

Objective:To investigate the conversion of stromal vascular fraction (SVF) in the microenvironment of radiation-induced skin injuries to provide guidance for clinical applications.Methods:Based on a random number table, C57BL/6N mice were categorized into four groups: the blank control, negative control, acute injury, and chronic injury groups, with each group containing 25 mice. The backs of mice in the blank control, acute injury, and chronic injury groups were exposed to 15 Gy X-ray irradiation. Then, the mice in the negative control, acute injury, and chronic injury groups were injected subcutaneously with the SVF derived from B6/G-R mice. The survival of these mice was observed 1, 3, 7, 14, and 21 d after the injection through fluorescence tracing and in vivo imaging. Accordingly, the clinical SVF injection regimens were optimized based on the experimental result of mice. Finally, local SVF injection was performed on different frequencies for patients in different wound conditions, with the efficacy being observed. Results:The fluorescence of SVF was observed from the tissue slices of the acute injury, chronic injury, and negative control groups 14 d post-injection. The result showed that the fluorescence intensity of SVF 1, 3, and 7 d post-injection was in the order of the negative control group > the acute injury group > the chronic injury group. The acute injury group ranked at the top and the chronic injury group remained at the bottom 14 d after the injection. The fluorescence of SVF in each group was barely detected 21 d after the injection. Compared to the negative control group, the acute injury group exhibited statistical differences only 14 d post-injection ( t = 4.11, P < 0.05), while the chronic injury group displayed statistical differences 1, 3, 7, and 14 d after the injection ( t = 3.88-5.74, P < 0.05). Furthermore, the acute injury group exhibited significantly higher fluorescence intensity of SVF than the chronic injury group ( t = 4.73-8.38, P < 0.05). The half-life of SVF for the negative control, acute injury, and chronic injury groups was 6.336, 6.014, and 2.163 d, respectively. As indicated by the application of SVF transplantation based on traditional surgical protocols in the clinical trial, SVF can significantly promote wound repair, with earlier SVF transplantation being more beneficial for wound healing. Conclusions:The conversion of SVF differs in the microenvironments of acute and chronic radiation-induced skin injuries. This can serve as an essential guide for the administration timing and injection frequency of SVF in clinical applications.

Based on the theory of "one qi circulation" founded by HUANG Yuanyu， the core disease mechanism of colorectal cancer is the innate spleen deficiency and stomach qi failing to bear downward， which leads to the turbidity assemble in large intestine， forming the carcinoma toxin， and ultimately transforms into colorectal cancer. The treatment should base on recovering the circulation of qi， Huangya Decoction （黄芽汤） as the basic formula， the circulation of qi ascending and descending as the base， adjusting ascending and descending together with Xiaqi Decoction （下气汤）， and differentiating the syndrome on yin-yang excess-deficiency； for spleen-kidney yang deficiency syndrome， treated with Tianhun Decoction （天魂汤） to supplement liver， kidney and assist yang； for liver-kidney yin deficiency syndrome， treated wtih Dipo Decoction （地魄汤） to supplement lung， kidney， and assist yang. They jointly prompt one qi circulation to provide the thoughts for the treatment of colorectal cancer by traditional Chinese medicine.

ObjectiveTo observe the effect of Coptidis Rhizoma and Ophiopogonis Radix on renal tissue injury and epidermal growth factor receptor （EGFR）/phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt） signaling pathway in rats with diabetic nephropathy （DN） and explore its possible mechanism of delaying DN. MethodThirty-six male Wistar rats were randomly divided into a normal group （6 rats） and a model group （30 rats）. The model group was fed with a high-fat and high-sugar diet combined with streptozotocin （STZ） to establish a rat model of type 2 diabetes. After the successful preparation of the model， the rats were randomly divided into the model group， low， medium， and high dose groups of Coptidis Rhizoma and Ophiopogonis Radix （100， 200， 400 mg·kg^-1）， and metformin group （200 mg·kg^-1）. After administration， the levels of fasting blood glucose （FBG）， 24 h urine protein （24 h-UTP）， creatinine （SCr）， urea nitrogen （BUN）， and uric acid （UA） were detected. Hematoxylin-eosin （HE） staining and Masson staining were used to observe the pathological changes of renal tissue in rats. Western blot and Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） were used to detect the related protein expression of EGFR， PI3K， and Akt and their mRNA expression levels in the renal tissue of rats in each group. ResultsCompared with the normal group， the levels of FBG， SCr， BUN， UA， 24 h-UTP， and kidney index in the model group were significantly increased （P<0.01）， most renal tubular epithelial cells were necrotic， and the content of collagen in glomeruli was significantly increased （P<0.01）. Compared with the model group， the above indexes of rats in each administration group were improved to varying degrees. The FBG， SCr， BUN， UA， 24 h-UTP， and kidney index of rats in each dose group and metformin group were significantly decreased （P<0.01， P<0.05）. The necrosis degree of renal tubular epithelial cells was reduced， and the fibrosis area was decreased （P<0.01）. There related protein and mRNA expressions of EGFR， PI3K， and Akt were significantly increased （P<0.05， P<0.01）. ConclusionCoptidis Rhizoma and Ophiopogonis Radix can alleviate renal tissue injury in rats with DN， and their mechanism may be related to the regulation of the EGFR/PI3K/Akt signaling pathway.

Objective To formulate the quantitative grip strength training program for application in the postoperative patients with autogenous arteriovenous internal fistula,and to evaluate its effect on the mat-uration and initial use of autogenous arteriovenous internal fistula.Methods A total of 98 patients with ce-phalic venous radial arterial anastomosis internal fistula formation surgery in Shenzhen Hospital of Southern Medical University from September 2021 to November 2022 were selected as the study subjects by the conven-ience sampling method.According to the follow-up time,they were divided into the observation group (n=41) and control group (n=42).The observation group adopted the quantitative grip strength training for function-al exercise of the limb on the side of internal fistula,while the control group adopted the conventional grip training for functional exercise of the limb on the side of internal fistula.In postoperative 8 weeks,the matura-tion rate of internal fistula,natural blood flow amount of internal fistula,internal diameter of cephalic vein,pre-pump pressure used in the initial stage of internal fistula and the incidence rate of internal fistula complica-tions were evaluated in the two groups.Results Compared with the control group,the maturation rate of in-ternal fistula in the observation group was higher (97.6％ vs. 83.3％).The inner diameter of cephalic vein and natural blood flow amount of internal fistula in the observation group were larger than those in the control group[(5.24±0.66)mm vs. (4.63±0.59)mm;(1215.38±562.99)mL/min vs. (955.75±341.94)mL/min],the pre-pump pressure used at the initial stage of internal fistula in the observation group was lower than that in the control group[(119.20±19.83)mmHg vs. (135.74±17.07)mmHg],and the differences were statistically significant (P<0.05).Conclusion The quantitative grip strength training could increase the postoperative maturity rate of patients's internal fistula,and is beneficial to the use in the initial stage of internal fistula.

Objective To isolate and culture neural crest cells(NCCs)from lung tissue of mice and to identify the characteristics of the cells in order to provide a new cell model for studying lung injury and injure repair.Methods The mT/mG dual-fluorescence reporter mice and Wnt1-Cre transgenic mice were hybridized,and mT/mG;Wnt1-Cre transgenic mice were screened to obtain enhanced green fluorescent protein(EGFP)permanently labeled NCCs.Cell suspension of mouse lung tissue was prepared by enzymolysis.EGFP+cells(namely NCCs)were har-vested by flow cytometry.Primary culture was performed with DMEM/F12 culture medium optimized in the labora-tory,NCCs was characterized by immunofluorescence microscopy.Then NCCs differentiation was directed by mouse bone marrow mesenchymal stem cells osteogenic induction.Results The mT/mG of EGFP permanently labeled NCCs was successfully obtained by hybridization and high-purity NCCs were isolated from Wnt1-Cre transgenic mice lung tissue.They can be cultured in vitro and with spindle morphology which was,similar to fibroblast adherent proliferation.NCCs expressed the neural crest stem cell marker Sox10 and induced to differentiate into osteoblasts.Conclusions NCCs isolated and cultured from lung tissue of mT/mG;Wnt1-Cre transgenic mice show stable prolif-eration and have the characteristics of neural crest stem cells,which may function as a potential cell model for re-search on lung tissue injury and the mechanism of repair.

Objective:In chronic hepatitis B (CHB) patients with previous 96-week treatment with tenofovir amibufenamide (TMF) or tenofovir disoproxil fumarate (TDF), we investigated the efficacy of sequential TMF treatment from 96 to 144 weeks.Methods:Enrolled subjects who were previously assigned (2:1) to receive either 25 mg TMF or 300 mg TDF with matching placebo for 96 weeks received extended or switched TMF treatment for 48 weeks. Efficacy was evaluated based on virological, serological, biological parameters, and fibrosis staging. Statistical analysis was performed using the McNemar test, t-test, or Log-Rank test according to the data. Results:593 subjects from the initial TMF group and 287 subjects from the TDF group were included at week 144, with the proportions of HBV DNA<20 IU/ml at week 144 being 86.2% and 83.3%, respectively, and 78.1% and 73.8% in patients with baseline HBV DNA levels ≥8 log10 IU/ml. Resistance to tenofovir was not detected in both groups. For HBeAg loss and seroconversion rates, both groups showed a further increase from week 96 to 144 and the 3-year cumulative rates of HBeAg loss were about 35% in each group. However, HBsAg levels were less affected during 96 to 144 weeks. For patients switched from TDF to TMF, a substantial further increase in the alanine aminotransferase (ALT) normalization rate was observed (11.4%), along with improved FIB-4 scores.Conclusion:After 144 weeks of TMF treatment, CHB patients achieved high rates of virological, serological, and biochemical responses, as well as improved liver fibrosis outcomes. Also, switching to TMF resulted in significant benefits in ALT normalization rates (NCT03903796).

Objective:In chronic hepatitis B (CHB) patients with previous 96-week treatment with tenofovir amibufenamide (TMF) or tenofovir disoproxil fumarate (TDF), we investigated the safety profile of sequential TMF treatment from 96 to 144 weeks.Methods:Enrolled subjects that previously assigned (2:1) to receive either 25 mg TMF or 300 mg TDF with matching placebo for 96 weeks received extending or switching TMF treatment for 48 weeks. Safety profiles of kidney, bone, metabolism, body weight, and others were evaluated.Results:666 subjects from the initial TMF group and 336 subjects from TDF group with at least one dose of assigned treatment were included at week 144. The overall safety profile was favorable in each group and generally similar between extended or switched TMF treatments from week 96 to 144. In subjects switching from TDF to TMF, the non-indexed estimated glomerular filtration rate (by non-indexed CKD-EPI formula) and creatinine clearance (by Cockcroft-Gault formula) were both increased, which were (2.31±8.33) ml/min and (4.24±13.94) ml/min, respectively. These changes were also higher than those in subjects with extending TMF treatment [(0.91±8.06) ml/min and (1.30±13.94) ml/min]. Meanwhile, switching to TMF also led to an increase of the bone mineral density (BMD) by 0.75% in hip and 1.41% in spine. On the other side, a slight change in TC/HDL ratio by 0.16 (IQR: 0.00, 0.43) and an increase in body mass index (BMI) by (0.54±0.98) kg/m 2 were oberved with patients switched to TMF, which were significantly higher than that in TMF group. Conclusion:CHB patients receiving 144 weeks of TMF treatment showed favorable safety profile. After switching to TMF, the bone and renal safety was significantly improved in TDF group, though experienceing change in metabolic parameters and weight gain (NCT03903796).