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.

Objective : To investigate the protective effect of dimethyl fumarate(DMF) on maternal intrahepatic cholestasis(ICP) during pregnancy induced by di(2-ethylhexyl) phthalate(DEHP) exposure and its mechanism. Methods : Thirty-two 8-week-old female institute of cancer research(ICR) mice were randomly divided into 4 groups: Ctrl group, DEHP group, DMF group and DEHP+DMF group. DEHP and DEHP+DMF groups were treated with DEHP(200 mg/kg) by gavage every morning at 9:00 a.m. DMF and DEHP+DMF groups were treated with DMF(150 mg/kg) from day 13 to day 16 of gestation by gavage. After completion of gavage on day 16 of pregnancy, maternal blood, maternal liver, placenta, and amniotic fluid were collected from pregnant mice after a six-hour abrosia. The body weight of the mother rats and the body weight of the fetus rats were sorted and analyzed; the levels of total bile acid(TBA), alkaline phosphatase(ALP), aspartate aminotransferase/alanine aminotransferase(AST/ALT) in serum and TBA in liver, amniotic fluid and placenta were detected by biochemical analyzer; HE staining was used to observe the pathological changes of liver tissue; Quantitative reverse transcription PCR(RT-qPCR) was used to detect the expression levels of tumor necrosis factor-α(TNF-α), interleukin(IL)-6, IL-1, IL-18 and NOD-like receptor thermal protein domain associated protein 3(NLRP3) in the liver; Western blot was used to detect the expression of the nuclear factor KappaB(NF-κB) and NLRP3. Results : Compared with the control group, the body weight of the DEHP-treated dams and pups decreased(P<0.05); the levels of TBA, ALP, AST/ALT in the serum of dams and the levels of TBA in the liver, amniotic fluid, and placenta of dams increased(P<0.05); the histopathological results showed that liver tissue was damaged, bile ducts were deformed, and there was inflammatory cell infiltration around them; the levels of inflammation-related factors TNF-α, IL-6, IL-1, IL-18 and NLRP3 transcription in maternal liver increased(P<0.05); the expression of NF-κB and NLRP3 protein in maternal liver significantly increased( P<0. 05). Compared with the DEHP group,the body weight of both dams and fetuses significantly increased in DEHP + DMF group( P<0. 05); the levels of TBA,ALP,AST/ALT in the serum of dams and amniotic fluid of fetuses decreased( P<0. 05); the degree of liver lesions was improved; the transcription levels of inflammation-related factors TNF-α,IL-6,IL-1,IL-18 and NLRP3 in maternal liver decreased( P<0. 05); the expression of NF-κB and NLRP3 protein in maternal liver significantly decreased( P<0. 05). Conclusion DMF can effectively protect the DEHP exposure to lead to female ICP,and its mechanism may be through inhibiting the NF-κB/NLRP3 pathway and reducing liver inflammation.

ObjectiveIn order to provide a reference for the optimization of preparation process of stir-fried Glycyrrhizae Radix et Rhizoma（sf-GRR）， the quality changes during the processing was studied. MethodsGlycyrrhizae Radix et Rhizoma was processed by stir-frying for 17 min， and samples were collected every 1 min during the processing. The appearance color of the samples was determined by visual analysis technology， the moisture and extract of the process samples were detected by the drying method and the hot extraction method of alcohol-soluble extract in the general rules of the 2020 edition of Chinese Pharmacopoeia（part Ⅳ）， and the contents of liquiritin apioside， liquiritin， isoliquiritin apioside， isoliquiritin， licoricesaponin G₂ and glycyrrhizic acid in the process samples were determined by high performance liquid chromatography（HPLC）. Then principal component analysis（PCA）， partial least squares-discriminant analysis（PLS-DA） and Spearman correlation analysis were used for clustering， discrimination and correlation analysis of the appearance color， moisture， extract and the contents of six internal components. Based on artificial neural network and random forest algorithm， the prediction model of processing degree of sf-GRR was established. On this basis， based on the five principles of quality marker（Q-Maker）， explore the monitoring Q-Maker of sf-GRR. ResultsThe color of Glycyrrhizae Radix et Rhizoma deepened after stir-frying， and the appearance color of the sample changed from light yellow to dark yellow during processing. During the stir-frying process， the moisture content showed a decreasing trend with the extension of processing time， while the extract content showed an increasing trend with the extension of processing time. After stir-frying， the contents of liquiritin apioside， liquiritin and licoricesaponin G₂ showed an overall decreasing trend， while the contents of isoliquiritin apioside and isoliquiritin increased， and the content of glycyrrhizic acid increased slightly. The correlation analysis showed that moisture was positively correlated with brightness（L^*） and red/green value（a^*）， and negatively correlated with yellow/blue value（b^*） and total color difference（E^*ab）. Isoliquiritin apioside and isoliquiritin had negative correlation with L^* and a^*， and positive correlation with b^* and E^*ab. The processing process of sf-GRR could be divided into two stages of the early stage（0-14 min） and the late stage（15-17 min）， and could be divided into three stages of the early stage（0-6 min）， the middle stage（7-14 min） and the late stage（15-17 min） by combining the moisture， extract， the contents of 6 components and color values. Based on artificial neural network analysis and random forest algorithm， isoliquiritin apioside， isoliquiritin， liquiritin and glycyrrhizic acid were selected as monitoring markers for sf-GRR. ConclusionBased on the analysis of the exterior-interior indicators of process samples of sf-GRR， this paper ultimately identifies four processing monitoring markers， which can provide a basis for optimizing the processing technology of sf-GRR.

ObjectiveTo investigate the effect of galvanic vestibular stimulation on stroke patients with lateropulsion. MethodsFrom February to October, 2023, 30 stroke patients with lateropulsion in the First Affiliated Hospital of Nanjing Medical University were divided into control group (n = 15) and experimental group (n = 15) randomly. The control group received routine rehabilitation and sham galvanic vestibular stimulation, and the experimental group received routine rehabilitation and true galvanic vestibular stimulation, for two weeks. They were assessed with Scale for Contraversive Pushing (SCP), subjective visual vertical (SVV), Line Cancellation Test (LCT), Star Cancellation Test (SCT), Berg Balance Scale (BBS), Holden Functional Ambulation Category (FAC) and Barthel Index (BI) before and after treatment. ResultsAll the indexes improved in both groups after intervention (|t| > 2.461, Z > 3.000, P < 0.05), except the SVV orientation, SVV certainty and SCT in the control group; while the SCP, SVV certainty, LCT and FAC were better in the experimental group than in the control group (|t| > 2.189, Z = -2.862, P < 0.05), and the differences before and after intervention were better in the experimental group than in the control group (|t| > 2.382, P < 0.05), except LCT. SCP was correlated with SVV orientation, SVV certainty, SCT, BBS, BI and FAC (|r| > 0.381, P < 0.05). ConclusionGalvanic vestibular stimulation can improve the lateropulsion, balance, walking function and activities of daily living in stroke patients, which may be related to improvement for spatial cognitive function, especially vertical perception.

Platelets have long been recognized as key players in hemostasis and thrombosis; however, there is growing evidence that they are also involved in cancer. Preclinical and clinical studies have shown that platelets can promote tumorigenesis and metastasis through various crosstalks between platelets and cancer cells. Platelets play an active role in all stages of tumorigenesis, including tumor growth, tumor cell extravasation, and metastasis. In addition, thrombocytosis in cancer patients is associated with poor patient survival. Platelets are also well-placed to coordinate local and distant tumor-host interactions due to the a- bundance of microparticles and exosomes. Therefore, antitumor drugs targeting platelets have great development and application prospects. The following will review the research progress of anti-tumor drugs targeting platelets.

Objective:To investigate the correlation factors of complete clinical response in idiopathic inflammatory myopathies(IIMs)patients receiving conventional treatment.Methods:Patients diagnosed with IIMs hospitalized in Peking University People's Hospital from January 2000 to June 2023 were in-cluded.The correlation factors of complete clinical response to conventional treatment were identified by analyzing the clinical characteristics,laboratory features,peripheral blood lymphocytes,immunological indicators,and therapeutic drugs.Results:Among the 635 patients included,518 patients finished the follow-up,with an average time of 36.8 months.The total complete clinical response rate of IIMs was 50.0％(259/518).The complete clinical response rate of dermatomyositis(DM),anti-synthetase syn-drome(ASS)and immune-mediated necrotizing myopathy(IMNM)were 53.5％,48.9％and 39.0％,respectively.Fever(P=0.002)and rapid progressive interstitial lung disease(RP-ILD)(P=0.014)were observed much more frequently in non-complete clinical response group than in complete clinical re-sponse group.The aspartate transaminase(AST),lactate dehydrogenase(LDH),D-dimer,erythrocyte sedimentation rate(ESR),C-reaction protein(CRP)and serum ferritin were significantly higher in non-complete clinical response group as compared with complete clinical response group.As for the treat-ment,the percentage of glucocorticoid received and intravenous immunoglobin(IVIG)were significantly higher in non-complete clinical response group than in complete clinical response group.Risk factor analysis showed that IMNM subtype(P=0.007),interstitial lung disease(ILD)(P=0.001),eleva-ted AST(P=0.012),elevated serum ferritin(P=0.016)and decreased count of CD4+T cells in peripheral blood(P=0.004)might be the risk factors for IIMs non-complete clinical response.Conclu-sion:The total complete clinical response rate of IIMs is low,especially for IMNM subtype.More effec-tive intervention should be administered to patients with ILD,elevated AST,elevated serum ferritin or decreased count of CD4+T cells at disease onset.

Objective To analyze the high risk factors of obstetric brachial plexus palsy(OBPP),and to explore how to evaluate the relationship between fault medical behavior and OBPP in the process of medical damage forensic identification.Methods A retrospective analysis was carried out on 25 cases of medical damage liability disputes related to OBPP from 2017 to 2021 in Beijing Fayuan Judicial Science Evidence Appraisal Center.The shortcomings of hospitals in birth weight assessment,delivery mode selection,labor process observation and shoulder dystocia management,and the causal relation-ship between them and the damage consequences of the children were summarized.Results Fault medi-cal behavior was assessed as the primary cause in 2 cases,equal cause in 10 cases,secondary cause in 8 cases,minor cause in 1 case,no causal relationship in 1 case,and unclear causal force in 3 cases.Conclusion In the process of forensic identification of OBPP,whether medical behaviors fulfill diagno-sis and treatment obligations should be objectively analyzed from the aspects of prenatal evaluation,de-livery mode notification,standardized use of oxytocin,standard operation of shoulder dystocia,etc.Meanwhile,it is necessary to fully consider the objective risk of different risk factors and the diffi-culty of injury prevention,and comprehensively evaluate the causal force of fault medical behavior in the damage consequences.

Objective To explore the eradication rate of human papillomavirus(HPV)and gestational outcome of patients with high-grade squamous intraepithelial disease of the cervix(HSIL)after loop electrosurgical excision procedure(LEEP)by transvaginal dissection of the vesicorectal form the cervix.Methods A total of 53 patients treated with LEEP by transvaginal dissection of the vesicorectal form the cervix in Obstetrics and Gynecology Hospital,Fudan University from Jan to Dec,2019 were investigated.Clinical information of cervical cytological examination,HPV test and cervical biopsy under colposcopy were followed up for 6,12 and 24 months post-LEEP were collected.HPV infection in these 53 patients were compared before and after LEEP surgery.The rate of successful fertility of the cohort,the HPV conversion rate of patients with hysterectomy and LEEP done were compared.The association between the pathological type and positive surgical margin and the association between HPV infection type and positive surgical margin were analyzed.Results HPV infection rate of was 94.3%(50/53)and the proportion of HPV16 and/or 18 infection was 75.5%(40/53).Mono-HPV infection rate(69.8%,37/53)was significantly higher than mixed HPV infection rate(22.7%,13/53).Thirty-eight patients(71.7%)were found with positive surgical margin in previous LEEP operation.Fifteen patients had recurrence(28.3%)and 40 patients(75.5%)successfully delivered baby after surgery.Postoperative pathology was mainly HSIL,accounting for 66%(30/53),and 28.3%patients(15/53)had no pathological change.Forty cases had satisfying fertility-conservative operation outcome with negative surgical margin,and 38 patients eradicated HPV infection after LEEP,which took up 95%of patients with satisfying fertility-conservative operation.There was no significant difference of positive resection margin rate in between groups of HPV16/18 infection and other types.Five cases had successful delivery(12.5%,5/40)with 1 case of vaginal delivery and 4 cases of cesarean section.Among these 5 cases,3 cases undertook preventive cervical cerclage,with 1 case of vaginal delivery and 2 cases of cesarean sections.Conclusion HPV eradication rate and surgical outcome could be significantly improved by LEEP with transvaginal dissection of the vesicorectal from the cervix,which satisfied the fertility preservation of females at reproductive age.

BACKGROUND:Croton cream can activate ERK pathways and have anti-apoptotic effects on neuronal cells.It is not clear whether it synergistically exerts anti-apoptotic effects by inhibiting the activation of JNK and p38 pathways. OBJECTIVE:To explore the effects and mechanisms of croton cream on neuronal damage and apoptosis in the ischemic cortex of rats with cerebral ischemia-reperfusion injury. METHODS:(1)Ninety Sprague-Dawley rats were randomly divided into sham operation group,model group,croton cream low-dose group,croton cream medium-dose group,croton cream high-dose group and nimodipine group,with 15 rats in each group.Except for the sham operation group,animal models of middle cerebral artery occlusion were prepared in rats by the thread method.Rats in the three croton cream groups were given 20,40,and 60 mg/kg croton cream,respectively.Rats in the sham operation and model groups were given the same amount of normal saline,once a day,for 7 consecutive days.The optimal concentration of croton cream,namely the high dose of croton cream,was selected based on neurological deficit score,TTC staining,brain tissue water content,hematoxylin-eosin staining and Nissl staining.(2)Another 120 Sprague-Dawley rats were randomly divided into sham operation group,model group,croton cream group,JNK inhibitor group,croton cream+JNK inhibitor group,p38 MAPK inhibitor group,croton cream+p38 MAPK inhibitor group,and nimodipine group,with 15 rats in each group.Animal models of middle cerebral artery occlusion were prepared using the thread method in all the groups except in the sham operation group.Thirty minutes before modeling,10 μL of SP600125(JNK inhibitor)and 10 μL of SB203580(p38 MAPK inhibitor)were injected into the lateral ventricle of the rats,respectively.Rats in croton cream groups were intragastrically given 60 mg/kg croton cream.Seven days later,the JNK/p38 MAPK signaling pathway,apoptosis-related proteins and cell apoptosis were detected by western blot,TUNEL staining and flow cytometry,respectively. RESULTS AND CONCLUSION:(1)Compared with the sham operation group,neurological deficit score,cerebral water content,cerebral infarction volume and apoptosis rate were significantly increased in the model group(P<0.05),where nerve cells showed scattered distribution.Compared with the model group,neurological deficit score,water content of brain tissue and cerebral infarction volume were significantly decreased in the croton cream medium-dose group,high-dose group and nimodipine group(P<0.05),and the pathological morphology of nerve cells was significantly improved.(2)Compared with the JNK inhibitor group,p-JNK/JNK,p-p38/p38 and Bax expressions in rat brain tissue and the apoptotic rate were significantly decreased in the croton cream+inhibitor groups(P<0.05),while the expression of and Bcl-2 was significantly increased(P<0.05).To conclude,croton cream may inhibit the activation of JNK/p38 MAPK signaling pathway and reduce neuronal apoptosis to achieve neuroprotective effects in rats with cerebral ischemia-reperfusion injury.