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.

Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.

Biomolecular condensates are formed through phase separation of biomacromolecules such as proteins and RNAs. These condensates exhibit liquid-like properties that can futher transition into more stable material states. They form complex internal structures via multivalent weak interactions, enabling precise spatiotemporal regulations. However, the use of inconsistent and non-standardized terminology has become increasingly problematic, hindering academic exchange and the dissemination of scientific knowledge. Therefore, it is necessary to discuss the terminology related to biomolecular condensates in order to clarify concepts, promote interdisciplinary cooperation, enhance research efficiency, and support the healthy development of this field.

Aim To investigate the role of metabolites of eicosapentaenoic acid (EPA) in promoting the transdifferentiation of pancreatic α cells to β cells. Methods Male C57BL/6J mice were injected intraperitoneally with 60 mg/kg streptozocin (STZ) for five consecutive days to establish a type 1 diabetes (T1DM) mouse model. After two weeks, they were randomly divided into model groups and 97% EPA diet intervention group, 75% fish oil (50% EPA +25% DHA) diet intervention group, and random blood glucose was detected every week; after the model expired, the regeneration of pancreatic β cells in mouse pancreas was observed by immunofluorescence staining. The islets of mice (obtained by crossing GCG

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 evaluate the efficacy and safety of brexpiprazole in treating acute schizophrenia.Methods Patients with schizophrenia were randomly divided into treatment group and control group.The treatment group was given brexpiprozole 2-4 mg·d-1 orally and the control group was given aripiprazole 10-20 mg·d-1orally,both were treated for 6 weeks.Clinical efficacy of the two groups,the response rate at endpoint,the changes from baseline to endpoint of Positive and Negative Syndrome Scale(PANSS),Clinical Global Impression-Improvement(CGI-S),Personal and Social Performance scale(PSP),PANSS Positive syndrome subscale,PANSS negative syndrome subscale were compared.The incidence of treatment-related adverse events in two groups were compared.Results There were 184 patients in treatment group and 186 patients in control group.After treatment,the response rates of treatment group and control group were 79.50％(140 cases/184 cases)and 82.40％(150 cases/186 cases),the scores of CGI-I of treatment group and control group were(2.00±1.20)and(1.90±1.01),with no significant difference(all P＞0.05).From baseline to Week 6,the mean change of PANSS total score wese(-30.70±16.96)points in treatment group and(-32.20±17.00)points in control group,with no significant difference(P＞0.05).The changes of CGI-S scores in treatment group and control group were(-2.00±1.27)and(-1.90±1.22)points,PSP scores were(18.80±14.77)and(19.20±14.55)points,PANSS positive syndrome scores were(-10.30±5.93)and(-10.80±5.81)points,PANSS negative syndrome scores were(-6.80±5.98)and(-7.30±5.15)points,with no significant difference(P＞0.05).There was no significant difference in the incidence of treatment-related adverse events between the two group(69.00％vs.64.50％,P＞0.05).Conclusion The non-inferiority of Brexpiprazole to aripiprazole was established,with comparable efficacy and acceptability.

Aquaporin 5(AQP5),as the main water transport protein in the body,can regulate lung diseases by regulating airway mucus secretion,pulmonary inflammation,and lung function.Programmed cell death(PCD)plays a crucial role in chronic obstructive pulmonary disease(COPD).AQP5 may affect the development of COPD by regulating PCDs.This article reviews the molecular regulatory mechanism of AQP5 on apoptosis,autophagy,iron death and pyroptosis in PCDs in recent years,and further discusses its effect on COPD in order to provide theoretical support for clinical prevention and treatment of COPD.

Objective To explore the protective mechanism of honey-processed Hedysari Radix in regulating intestinal mucosal injury in rats with spleen qi deficiency.Methods The three-factor composite modeling method of bitter cold diarrhea,overwork and hunger and satiety disorder was used to construct a spleen qi deficiency model rats.After the model was successfully made,they were randomly divided into model group,honey-processed Hedysari Radix group and probiotic group,with 15 animals in each group.Another 15 normal rats were taken as the blank group.The honey-processed Hedysari Radix group was given 12.6 g·kg-1 water decoction of honey-processed Hedysari Radix by gavage,the probiotics group was given Bifidobacterium Lactobacillus triple viable tablets suspension at a dose of 0.625 g·kg-1,and the blank group and the model group were given the same dose of distilled water.The rats in the four groups were administered once a day for 15 days.Enzyme-linked immunosorbent assay was used to detect diamine oxidase(DAO)in serum,D-lactic acid(D-LA),secretory immunoglobulin A factor,and Western blotting was used to detect the expression levels of AMP-activated protein kinase(AMPK),zonula occludens-1(ZO-1)and occludin in colon tissues.Results The serum levels of DAO in the blank group,model group,honey-processed Hedysari Radix group and probiotic group were(138.93±9.78),(187.95±12.90),(147.21±6.92)and(166.47±3.37)pg·mL-1;the contents of D-LA were(892.23±49.17),(1 099.84±137.64),(956.56±86.04)and(989.61±51.75)μg·L-1;the contents of SIgA in colon tissues were(14.04±1.42),(11.47±2.39),(11.84±1.49)and(12.93±1.65)μg·mL-1;the relative expression levels of ZO-1 protein in colon tissues were 1.18±0.11,0.42±0.04,0.77±0.05 and 0.95±0.07;the relative expression levels of occludin protein were 1.35±0.31,0.61±0.17,1.19±0.19 and 0.88±0.13;the relative expression levels of AMPK protein were 0.91±0.02,0.35±0.09,0.74±0.08 and 0.59±0.11.Compared with the model group,there were significant differences in the serum content of DAO and D-LA,SIgA content in colon,and the content of ZO-1,occludin and AMPK protein in the honey-processed Hedysari Radix group(P＜0.01,P＜0.05).Conclusion Honey-processed Hedysari Radix can enhance the protective effect on the intestinal mucosa of rats with spleen qi deficiency by regulating the expression of related inflammatory cytokines,intestinal mucosal upper cell enzymes and tight junction proteins in rats with spleen qi deficiency.

Objective This study aimed to compare the current Essen rabies post-exposure immunization schedule(0-3-7-14-28)in China and the simple 4-dose schedule(0-3-7-14)newly recommended by the World Health Organization in terms of their safety,efficacy,and protection. Methods Mice were vaccinated according to different immunization schedules,and blood was collected for detection of rabies virus neutralizing antibodies(RVNAs)on days 14,21,28,35,and 120 after the first immunization.Additionally,different groups of mice were injected with lethal doses of the CVS-11 virus on day 0,subjected to different rabies immunization schedules,and assessed for morbidity and death status.In a clinical trial,185 rabies-exposed individuals were selected for post-exposure vaccination according to the Essen schedule,and blood was collected for RVNAs detection on days 28 and 42 after the first immunization. Results A statistically significant difference in RVNAs between mice in the Essen and 0-3-7-14 schedule groups was observed on the 35th day(P<0.05).The groups 0-3-7-14,0-3-7-21,and 0-3-7-28 showed no statistically significant difference(P>0.05)in RVNAs levels at any time point.The post-exposure immune protective test showed that the survival rate of mice in the control group was 20%,whereas that in the immunization groups was 40%.In the clinical trial,the RVNAs positive conversion rates on days 28(14 days after 4 doses)and 42(14 days after 5 doses)were both 100%,and no significant difference in RVNAs levels was observed(P>0.05). Conclusion The simple 4-dose schedule can produce sufficient RVNAs levels,with no significant effect of a delayed fourth vaccine dose(14-28 d)on the immunization potential.

Objective:To establish a total normalized productive maintenance(TnPM)model for medical equipment,and to explore its application value in the management of multi-source treatment equipment.Methods:In accordance with the principles of self-management,economic efficiency and dynamic improvement,the TnPM management mode of the medical equipment lifecycle management system was developed.22 multi-source treatment equipment in clinical use in the of department of burn and plastic surgery of The Second Affiliated Hospital of Air Force Medical University were selected and divided into a control group(16 units)and an observation group(18 units,including 12 of control group and 6 newly added units)according to different management modes.The control group implemented the traditional management mode,and the observation group adopted TnPM management mode.The operation quality,comprehensive efficiency and team management capabilities of the two groups were compared.Results:The equipment failure rate of the observation group was(4.82±0.21)%,which was lower than that of traditional group,the self-repair rate,maintenance rate and operating standard rate were(91.63±3.59)%,(96.60±2.47)%and(97.31±1.54)%,respectively,which were higher than those of the control group,the difference was statistically significant(t=2.434,5.246,4.525,5.311,P<0.05).The equipment availability rate,performance index and quality index of the observation group were(90.82±2.78)%,(97.03±2.24)%and(97.85±1.26)%,respectively,which were higher than those of control group,the difference was statistically significant(t=6.231,4.671,5.997,P<0.05).The assessment scores of the personnel involved in the equipment on job responsibilities,basic equipment theory,usage assurance level and management performance of observation group were(93.95±2.81)points,(91.45±2.47)points,(90.75±2.54)points and(93.08±3.34)%,respectively,which higher than those of the control group,the difference was statistically significant(t=2.831,3.979,6.472,4.001,P<0.05).Conclusion:The TnPM management mode can improve the operation quality of equipment in the treatment of clinical patients,reduce the incidence of failure,enhance the comprehensive efficiency of equipment and clinical service level,and promote the construction of a management team.