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: By analyzing the correlation between genotypes and phenotypes, we explored the impact of the variant c.917T>C (p.L306P) in the ABO*B.01 allele on the expression and function of B-glycosyltransferase (GTB). This study aims to elucidate the molecular mechanisms underlying the occurrence of this subtype. METHODS: The study subjects included a blood donor specimen with incompatible forward and reverse ABO typing results. ABO phenotyping was determined using ABO blood group serology and GTB activity testing. Subsequently, Sanger sequencing and third-generation sequencing based on the PacBio platform were employed to sequence the ABO gene, resulting in the determination of haplotype sequences. Mutations were identified through sequence alignment. An in vitro cell expression system was established to assess the impact of the mutation site on antigen expression. RESULTS: The index case in this study was identified as B subtype with the allelic genotype c.917T>C in ABO*B.01/ABO*O.01.01 , which has not been previously reported. in vitro expression results revealed decreased levels of GTB expression and overall GTB activity in the mutant cells. Furthermore, the expression of the B antigen on the cell membrane was weaker in the mutant cells compared to the wild-type cells. CONCLUSION The p.L306P variation caused by the c.917T>C mutation in the ABO*B.01 allele may be a genetic factor contributing to the reduced expression of B antigens on the surface of red blood cells.
Humans ; ABO Blood-Group System/genetics* ; Alleles ; Genotype ; Mutation ; Glycosyltransferases/genetics* ; Haplotypes ; Phenotype

The incomplete degradation of tumour cells by macrophages (Mϕ) is a contributing factor to tumour progression and metastasis, and the degradation function of Mϕ is mediated through phagosomes and lysosomes. In our preliminary experiments, we found that overactivation of NADPH oxidase 2 (NOX2) reduced the ability of Mϕ to degrade engulfed tumour cells. Above this, we screened out liquiritin from Glycyrrhiza uralensis Fisch, which can significantly inhibit NOX2 activity and inhibit tumours, to elucidate that suppressing NOX2 can enhance the ability of Mϕ to degrade tumour cells. We found that the tumour environment could activate the NOX2 activity in Mϕ phagosomes, causing Mϕ to produce excessive reactive oxygen species (ROS), thus prohibiting the formation of phagolysosomes before degradation. Conversely, inhibiting NOX2 in Mϕ by liquiritin can reduce ROS and promote phagosome-lysosome fusion, therefore improving the enzymatic degradation of tumour cells after phagocytosis, and subsequently promote T cell activity by presenting antigens. We further confirmed that liquiritin down-regulated the expression of the NOX2 specific membrane component protein gp91 phox, blocking its binding to the NOX2 cytoplasmic component proteins p67 phox and p47 phox, thereby inhibiting the activity of NOX2. This study elucidates the specific mechanism by which Mϕ cannot degrade tumour cells after phagocytosis, and indicates that liquiritin can promote the ability of Mϕ to degrade tumour cells by suppressing NOX2.

Objective To investigate the implementation of surveillance,prevention and control measures for healthcare-associated infection(HAI)in maternal and child healthcare(MCH)institutions,and provide policy evi-dence for optimizing HAI prevention and control in MCH institutions.Methods Stratified sampling was conducted among the MCH institutions at provincial,municipal and county levels in 8 provinces/autonomous regions.A uni-fied questionnaire was designed and the online survey was conducted through"Questionnaire Star".Results The data from 123 MCH institutions were included in the analysis.90.24％of the MCH institutions carried out compre-hensive surveillance on HAI.The ratios of MCH institutions which implemented targeted surveillance on HAI in neonatal intensive care unit(NICU),surgical site infection,multidrug-resistant organisms(MDROs)and HAI in intensive care units(non-NICU excluded)were 89.66％,85.96％,80.77％,and 74.19％,respectively.51.22％MCH institutions adopted information surveillance system on HAI cases.94.31％MCH institutions carried out surveillance on hand hygiene compliance.Over 90％MCH institutions carried out surveillance on environment hy-giene in high-risk departments.71.54％MCH institutions conducted centralized cleaning,disinfection,sterilization and supply for reusable medical instruments in the central sterile supply department(CSSD).Over 90％MCH insti-tutions established three-level pre-examination triage systems.86.18％set up transitional wards.MCH institutions generally adopted a management model with established effective communication,full appointment visits,and sepa-rate visits for special medical groups,such as registered pregnant women,high-risk newborns,healthcare groups,and long-term rehabilitation patients.However,the ratio of institutions conducting on-line follow-up visits was less than 50％.Conclusion MCH institutions have generally carried out comprehensive and targeted surveillance on HAI.Information surveillance need to be facilitated.Hand hygiene and environmental hygiene surveillance has been popularized to a certain extent at all levels of MCH institutions.The cleaning,disinfection,sterilization,and supply processes of reusable medical devices in a few MCH institutions are not standardized.Special medical populations get effective management.On-line healthcare is to be further promoted.

Based on the long bud stage phenotype of a new Lonicera japonica Flos variety "Huajin 6", using "Huajin 6" and "Da Mao Hua" as materials, probing the mechanism of its phenotype formation. Detection of endogenous Jasmonic acid hormones (JAs) content; the genes related to jasmonic acid (JA) synthesis were identified by transcriptome analysis of Lonicera japonica; flower buds and flowers of "Huajin 6" and "Da Mao Hua" were collected at different periods, and the qRT-PCR (quantitative real-time PCR) technique was used to analyze the trend of the expression of synthesis-related enzyme genes in Lonicera japonica Flos during the bud stage. The study found that the content of JAs in "Huajin 6" Lonicera japonica Flos was significantly lower than that in "Da Mao Hua"; applying exogenous methyl-jasmonate (MeJA) to "Huajin 6" can restore its flowering phenotype, making it close to wild type Lonicera japonica Flos; there are significant differences in the expression of two allene oxide synthase genes (AOS), three lipoxygenase genes (LOX), and two allene oxide cyclase genes (AOC) in the flowers and buds of "Huajin 6" and "Da Mao Hua" at different periods. It is hypothesized that the low expression of JA synthesis-related enzyme genes in " Huajin 6" leads to the blockage of JA synthesis, which causes the formation of the long bud phenotype. This study laid a certain foundation for the genetic breeding of Lonicera japonica, provided a new idea for the improvement of Lonicera japonica varieties, and provided a reference for the study of JAs in plant flower organs.

Objective To investigate the therapeutic effect and mechanism of astragaloside Ⅳ on systemic lupus erythematosus(SLE)mice.Methods A total of 40 female spontaneous MRL/lpr SLE model mice were randomly divided into five groups:model group,Prednisone group,astragaloside Ⅳ group,astragaloside Ⅳ+CHPG[nuclear factor KappaB(NF-κB)pathway activator]group and astragaloside Ⅳ+Nigerian[NOD-like receptor family pyrin domain containing protein 3(NLRP3)activator]group,with eight mice in each group.Eight female MRL/MpJ mice were used as normal group.During the administration,the body mass was weighted.After administration,the spleen,thymus and kidney were weighted,and the organ index was calculated.The 24-hour urinary protein level in urine samples,the biochemical indexes of creatinine(SCr),blood urea nitrogen(BUN),autoantibodies[antinuclear antibody(ANA),anti-double-stranded DNA(dsDNA)antibody,anti-snRNP/Sm antibody]and inflammatory mediators[interleukin(IL)-1β,IL-18]in blood samples were detected.The pathological damage of renal tissue was observed by hematoxylin-eosin(HE)staining,and the fibrosis of renal tissue was observed by Masson staining.The expressions of NF-κB/NLRP3 inflammasome pathway-related proteins in kidney and spleen tissues were detected by Western Blot.Results Compared with the model group,the body mass of mice in prednisone group and astragaloside Ⅳ group increased,the spleen index,thymus index and kidney index were decreased,the serum levels of ANA antibody,anti-dsDNA antibody and anti-snRNP/Sm antibody were decreased,the levels of SCr,BUN and 24-hour urine protein were decreased,the levels of IL-1 βand IL-18 wrere decreased,the ratios of p-p65/p65,p-IKBα/IKBα,cleaved caspase-1/pro caspase-1 and the relative expression of NLRP3 protein in kidney and spleen tissues were decreased(all P＜0.05),and the pathological damage and fibrosis of renal tissue in SLE mice were alleviated,there being no significant difference between the two administration groups(P＞0.05).NF-κB activator and NLRP3 inflammasome activator eliminated the improvement of astragaloside Ⅳ on the above indexes in SLE mice to a certain extent.Conclusion Astragaloside Ⅳ can improve the immune function of SLE mice,reduce renal injury and inflammatory response,and its mechanism may be related to its inhibition of the activation of NF-κB/NLRP3 inflammasome pathway.

Objective To explore preemptive analgesic effect of preoperative intramural tramadol injection in percutaneous kyphoplasty(PKP)of vertebrae following local anesthesia.Methods From August 2019 to June 2021,118 patients with thora-co lumbar osteoporotic fractures were treated and divided into observation group and control group,with 59 patients in each gruop.In observation group,there were 26 males and 33 females,aged from 57 to 80 years old with an average of(67.69±4.75)years old;14 patients on T11,12 patients on T12,18 patients on L1,15 patients on L2;tramadol with 100 mg was injected intramuscularly half an hour before surgery in observation group.In control group,there were 24 males and 35 females,aged from 55 to 77 years old with an average of(68.00±4.43)years old;19 patients on T11,11 patients on T12,17patients on L1,12 patients on L2;the same amount of normal saline was injected intramuscularly in control group.Observation indicators included operation time,intraoperative bleeding,visual analogue scale(VAS)evaluation and recording of preoperative(T0),intraoper-ative puncture(T1),and working cannula placement(T2)between two groups of patients,at the time of balloon dilation(T3),when the bone cement was injected into the vertebral body(T4),2 hours after the operation(T5),and the pain degree at the time of discharge(T6);adverse reactions such as dizziness,nausea and vomiting were observed and recorded;the record the patient's acceptance of repeat PKP surgery.Results All patients were successfully completed PKP via bilateral pedicle ap-proach,and no intravenous sedative and analgesic drugs were used during the operation.There was no significant difference in preoperative general data and VAS(T0)between two groups(P＞0.05).There was no significant difference in operation time and intraoperative blood loss between the two groups(P＞0.05).VAS of T1,T2,T3,T4 and T5 in observation group were all lower than those in control group(P＜0.05),and there was no significant difference in T6 VAS(P＞0.05).T6 VAS between two groups were significantly lower than those of T0,and the difference was statistically significant(P＜0.05).There was no signifi-cant difference in incidence of total adverse reactions between two groups(P＞0.05).There was a statistically significant differ-ence in the acceptance of repeat PKP surgery(P＜0.05).Conclusion Half an hour before operation,intramuscular injection of tramadol has a clear preemptive analgesic effect for PKP of single-segment thoracolumbar osteoporotic fracture vertebral body under local anesthesia,which could increase the comfort of patients during operation and 2 hours after operation,and improve patients satisfaction with surgery.

Objective To design a punching and positioning device for training Da Vinci surgical robots to improve the efficiency and accuracy of operation training.Methods The punching and positioning device mainly consisted of an abdominal girth,a connecting plate,a punching plate,a positioning disk and a punching cartridge.The abdominal girth had a long-strip shape and was made of stretch nylon elastic band;the connecting plate had a rectangular shape with its length direction perpendicular to the abdominal girth;the punching plate also had a rectangular shape and was made of hard silicone;the positioning plate was made of hard silicone and privided with a plated through hole;the punching cartridge were equipped with anti-fog components composed of heating wires and support strips,which had scale bars inside.Ten physicians were randomly divided into a control group and an experimental group,with 5 ones in each group.The two groups carried out positioning and punching respectively,with the traditional method for the control group and the device designed for the experimental group,which were compared in terms of the time consumption,ratio for lens fogging and number of collisions with the robotic arm.Results The experimental group had the time consumption and ratio for lens fogging lower significantly when compared with the control group(P＜0.05),while had no obvious difference in number of collisions with the robotic arm(P＞0.05),and the requirements of the training specifications were met.Conclusion The punching and positioning device has high efficiency and accuracy,and thus is worthy promoting for the operation training of surgical robots.[Chinese Medical Equipment Journal,2024,45(7):35-39]

Inhibiting the death receptor 3(DR3)signaling pathway in group 3 innate lymphoid cells(ILC3s)pre-sents a promising approach for promoting mucosal repair in individuals with ulcerative colitis(UC).Paeoniflorin,a prominent component of Paeonia lactiflora Pall.,has demonstrated the ability to restore barrier function in UC mice,but the precise mechanism remains unclear.In this study,we aimed to delve into whether paeoniflorin may promote intestinal mucosal repair in chronic colitis by inhibiting DR3 signaling in ILC3s.C57BL/6 mice were subjected to random allocation into 7 distinct groups,namely the control group,the 2％dextran sodium sulfate(DSS)group,the paeoniflorin groups(25,50,and 100 mg/kg),the anti-tumor necrosis factor-like ligand 1A(anti-TL1A)antibody group,and the IgG group.We detected the expression of DR3 signaling pathway proteins and the proportion of ILC3s in the mouse colon using Western blot and flow cytometry,respectively.Meanwhile,DR3-overexpressing MNK-3 cells and 2％ DSS-induced Rag1-/-mice were used for verification.The results showed that paeoniflorin alleviated DSS-induced chronic colitis and repaired the intestinal mucosal barrier.Simultaneously,paeoniflorin inhibited the DR3 signaling pathway in ILC3s and regulated the content of cytokines(interleukin-17A,granulocyte-macrophage colony stimulating factor,and interleukin-22).Alternatively,paeoniflorin directly inhibited the DR3 signaling pathway in ILC3s to repair mucosal damage indepen-dently of the adaptive immune system.We additionally confirmed that paeoniflorin-conditioned me-dium(CM)restored the expression of tight junctions in Caco-2 cells via coculture.In conclusion,paeoniflorin ameliorates chronic colitis by enhancing the intestinal barrier in an ILC3-dependent manner,and its mechanism is associated with the inhibition of the DR3 signaling pathway.

The disorder of group 3 innate lymphoid cells(ILC3)subgroup,such as the predominance of NCR-ILC3 but the deple-tion of NCR+ILC3,is unfavorable to damaged intestinal barrier repair,which leads to the prolongations and obstinacy of ulcerative colitis(UC).Our previous studies had shown that luteolin promoted NCRILC3 differentitating into NCR+ILC3 to improving the de-pletion of NCR+ILC3 in UC mice,while the mechanism is unclear.This article aimed to explore the underlying mechanism of luteolin enhancing the proportion NCR+ILC3.UC mice model was established with 2％DSS and Notch signaling was blocked,then luteolin was used to intervene.The results showed that the effect of luteolin on ameliorating disease symptoms in UC mice,including inhibit-ing the weight loss,reducing the pathological damage of colon mucosa,etc.,was diminished with blocking Notch signaling pathway.In addition,luteolin increased the proportion of NCR+ILC3,NCR+MNK3 and IL-22+ILC3,decreased intestinal permeability,pro-moted mucin secretion,and promoted ZO-1 and Occludin expression,the above effect of luteolin was neutralized by Notch inhibitor LY-411575.Luteolin activated the abnormally blocked Notch signaling pathway in UC mice.And molecular docking predicted the af-finity of luteolin for RBPJ to be-7.5 kcal·mol-1 in mouse,respectively;the affinity of luteolin for Notchl and RBPJ was respectively scored to be-6.4 kcal·mol-1 and-7.7 kcal·mol-1 homo sapiens.These results proved that luteolin is positive for enhancing the propor-tion of NCR+ILC3 via Notch signaling,and it provides a basis for targeting NCR+ILC3 for restoring intestinal barrier function to alle-viating ulcerative colitis.