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 compare next generation sequencing (NGS) library construction technology between probe hybridization capture and amplicon methods, and analyze the influencing factors of HLA genotyping resolution level and its prospects in clinical applications. [Methods] A total of 207 clinical samples with known typing results and samples from the proficiency testing plan were selected. The conformity rate of HLA genotyping results, allele coverage and typing data analysis indicators were confirmed, and the effects of two library construction methods on the level of HLA genotyping discrimination were compared. [Results] The concordance rate of 207 samples with the feedback results of PT or prior well-characterized HLA genotypes was 100%. Among them, 91 samples were captured using hybridization probe capture method. Compared with the original amplicon method, the hybridization probe capture method can distinguish the alleles of DRB1 and DPB1 that cannot be determined in 13 samples. The allelic imbalance of DRB1, DPA1, and DQB1 loci in 6 samples was resolved. Three samples were found to have missed detection of alleles at the DQA1 and DQB1 loci. [Conclusion] The performance indicators of hybridization probe capture and amplicon performance confirmation meet the requirements of clinical detection of HLA genotyping, which provides an experimental method and basis for clinical application.

OBJECTIVE To optimize the management model of drugs used in investigator-initiated trial （IIT）. METHODS With benchmarking analysis， based on the practical work experience of a tertiary specialized hospital in the field of IIT drug management in Shanghai， a thorough review was conducted， involving relevant laws， regulations， and academic literature to establish benchmark criteria and the evaluation standards. Starting from the initiation of IIT projects， a detailed comparative analysis of key processes was carried out， such as the receipt， storage， distribution， use and recycling of drugs for trial. The deficiencies in the current management of IIT drugs were reviewed in detail and a series of optimization suggestions were put forward. RESULTS It was found that the authorized records of drug management were missing， the training before project implementation was insufficient， and the records of receipt and acceptance of IIT drugs were incomplete. In light of these existing problems， improvement measures were put forward， including strengthening the training of drug administrators and stipulating that only drug administrators with pharmacist qualifications be eligible to inspect and accept drugs， etc. The related systems were improved， and 17 key points of quality control for the management of IIT drugs were developed. CONCLUSIONS A preliminary IIT drug management system for medical institutions has been established， which helps to improve the institutional X2023076） framework of medical institutions in this field.

Objective: In in vitro systems for differentiating and expanding natural killer (NK) cells, feeder cells provide essential cell-cell contact and paracrine signals that drive precursor proliferation and terminal maturation. However, existing xenogeneic feeder cells or tumor-derived genetically modified feeder cells pose risks of residual immunogenicity and malignant transformation, limiting clinical use. This study aims to develop a humanized mesenchymal-like stromal cell (hematopoietic organoid-derived human mesenchymal stromal cells, HO-hMSCs) derived from iPSC-based hematopoietic organoids, and elucidate its mechanisms of NK-supportive activity to enable a safe, efficient platform for clinical-grade NK cell production. Methods: Human induced pluripotent stem cells (iPSCs) were differentiated into hematopoietic organoids, from which HO-hMSCs were isolated. Flow-cytometric phenotyping and bulk RNA-sequencing were performed to compare HO-hMSCs with umbilical cord-derived MSCs (UC-hMSCs). The effect of HO-hMSCs on NK cell differentiation efficiency (CD3 CD56 ) and effector maturation (CD16 expression) were assessed by co-culture experiments, using UC-hMSCs as control. Results: 1) Hematopoietic organoid induction and NK differentiation: iPSCs were induced to form hematopoietic organoids using cytokine cocktails, which further differentiated into high-purity CD45 CD56 NK cells [(82.8%±12.07)% efficiency on day 21]. 2) HO-hMSC characteristics: HO-hMSCs exhibited upregulated expression of Notch pathway ligands (DLL4, JAG1, 4.06-8.04-fold), homeobox genes (HOXA3, HOXA5, log FC=1.28 and 1.44), and key regulators of NK development (GATA3, BCL11A) and cytokine receptors (IL7R, IL27RA, 6.76 to 13.34-fold increase). 3) Functional validation: Compared to UC-hMSCs, HO-hMSCs co-culture significantly enhanced NK cell proportion by 30.5% (P<0.05) and increased CD16 positivity (+20.5%). Conclusion: This study for the first time reveals that human hematopoietic organoid-derived HO-hMSCs possess potent hematopoietic niche-supportive activity. It provides a humanized, feeder-free platform for robust clinical-grade NK cell production and expands the translational utility of organoid technologies in cell therapy.

Objective To investigate the genetic causes of auditory neuropathy with optic atrophy in a family.Methods The proband's medical history and family history were inquired in detail,and relevant clinical examina-tions were performed to confirm the diagnosis of auditory neuropathy with optic atrophy,and the genetic pedigree of the family was drawn.Peripheral blood of proband(Ⅲ-7)was collected for whole exome sequencing,and the patho-genicity of the detected mutations were interpreted.Blood samples of proband's wife(Ⅲ-8),eldest daughter(Ⅳ-7),second daughter(Ⅳ-9)and son(Ⅳ-10)were tested for mutation sites by Sanger sequencing.Combined with clinical manifestations and examination results,the family was studied.Results The genetic pattern of this family was autosomal dominant.The proband showed decreased visual acuity at the age of 19,bilateral sensorineural deaf-ness at the age of 30,and decreased speech recognition rate.Among 20 members of the family of 5 generations,10(2 deceased)showed similar symptoms of hearing and visual impairment.Proband(Ⅲ-7),eldest daughter(Ⅳ-7)and son(Ⅳ-10)underwent relevant examination.Pure tone audiometry showed bilateral sensorineural deafness.ABR showed no response bilaterally.The 40 Hz AERP showed no response in both ears.OAE showed responses in some or all of the frequencies.No stapedial reflex was detected.The eye movement of Ⅲ-7 and Ⅳ-10 were reasona-ble in all directions,and color vision was normal.Ocular papilla atrophy was observed in different degrees in fundus examination.OCT showed thinning of optic disc nerve fibers in both eyes,and visual evoked potential showed pro-longed P100 wave peak.They were diagnosed as hereditary auditory neuropathy with optic atrophy.A mutation of the OPA1 gene c.1334G＞A(p.Arg445His,NM_015560.2)at a pathogenic locus on chromosome 3 was detected by whole exon detection in Ⅲ-7.The results of generation sequencing analysis showed that the OPA1 gene c.1334G＞A(p.Arg445His,NM_015560.2)mutation of chromosome 3 was also found in Ⅳ-7 and Ⅳ-10.Meanwhile,the gen-otypes of Ⅲ-8 and Ⅳ-9 were wild homozygous,that is,no mutation occurred.Conclusion The OPA1 c.1334G＞A(p.Arg445His,NM_015560.2)mutation site might be the pathogenic mutation in this family.

BACKGROUND:Irisin,a myokine isolated from the transmembrane protein FNDC5 by muscle cells during exercise,has the function of inducing the browning of white adipose tissue,but its effect on lipotoxicity-induced osteogenic differentiation and the mechanism is unclear. OBJECTIVE:To investigate the effect of irisin on the osteogenic ability of palmitic acid-induced bone marrow mesenchymal stem cells and the mechanism of action. METHODS:CCK-8 assay was used to detect the effect of different concentrations of palmitic acid on the proliferation of mouse bone marrow mesenchymal stem cells and the effect of irisin on the proliferation of mouse bone marrow mesenchymal stem cells in the presence of palmitic acid.After pretreatment with irisin and palmitic acid for 24 hours,osteogenic differentiation of mouse bone marrow mesenchymal stem cells was induced by alkaline phosphatase staining as well as qRT-PCR was performed to detect the expression of osteogenesis-related genes on day 7 of osteogenic induction culture.The expression of proteins related to the AMPK/BMP2/SMAD signaling pathway was detected by western blot assay.Alizarin red staining was conducted on day 21 to detect osteogenic differences. RESULTS AND CONCLUSION:(1)The CCK-8 assay results suggested that the amplification of bone marrow mesenchymal stem cells was inversely proportional to the concentration of palmitic acid,but at 0.02 mmol/L concentration,palmitic acid had no significant effect on the amplification of bone marrow mesenchymal stem cells,and irisin did not affect the proliferation of bone marrow mesenchymal stem cells when its mass concentration was in the range of 0.1-20 μg/L.(2)Alkaline phosphatase staining and alizarin red staining showed that palmitic acid inhibited the osteogenic differentiation ability of bone marrow mesenchymal stem cells.Irisin improved palmitic acid-induced osteogenic inhibition of bone marrow mesenchymal stem cells.qRT-PCR results showed that palmitic acid could cause the downregulation of osteogenic-related genes,and irisin could inhibit this trend.(3)Western blot assay results showed that compared with the palmitic acid intervention group,irisin treatment enhanced AMPK/BMP2/SMAD signal transduction in bone marrow mesenchymal stem cells.It is found that irisin can improve the osteogenic differentiation ability of bone marrow mesenchymal stem cells pretreated with palmitic acid,and proposed that the specific mechanism might be mediated by AMPK/BMP/SMAD signaling pathway.

Obiective Alzheimer’s disease (AD) is a degenerative disease of the central nervous system (CNS) caused by a variety of risk factors. There are various pathological changes, but apoptosis of the neurological meridian cells is one of the most important pathological bases. Hyperlipidemia is a high-risk factor for the development of AD, which can lead to increased levels of oxidized low-density lipoprotein (ox-LDL) in brain tissues. PCSK9 is a protease closely related to lipid metabolism, but studies have shown that it may be related to the development of AD. LRP1 is abundantly expressed in neuronal cells, and it is an important transporter for the clearance of Aβ. There is now a large amount of literature confirming that PCSK9 can induce the degradation of LRP1. PI3K/AKT is an important signaling pathway in vivo, which plays an important role in apoptosis, and there is now a large amount of literature confirming that LRP1 activates the PI3K/AKT pathway, which has an anti-apoptotic effect. So can PCSK9 affect the PI3K/AKT pathway through LRP1 and thus regulate neuronal apoptosis? This deserves further investigation.The aim of this study was to explore the role of PCSK9 in mediating ox-LDL pro-apoptotic neuronal cell death and its mechanism, and then further elaborate the mechanism of hyperlipidemia leading to neurodegenerative diseases such as AD. MethodsFirstly, PC12 cells were treated with different concentrations of ox-LDL (0, 25, 50, 75 and 100 mg/L) for 24 h. Oil red O staining was used to detect lipid accumulation in PC12 cells, Hoechst33258 staining and flow cytometry to detect apoptosis in PC12 cells, ELISA to detect the content of Aβ secreted by PC12, Western blot to detect expression of SREBP2, PCSK9 and LRP1. Then PC12 cells were treated with 75 mg/L ox-LDL for different times (0, 6, 12, 24, 48 h), and Western blot were performed to detect the expression of SREBP2, PCSK9 and LRP1. Finally, after transfecting 100 nmol/L PCSK9 siRNA into PC12 cells for 48 h, PC12 cells were treated with 75 mg/L ox-LDL for 24 h, Hoechst33258 staining and flow cytometry to detect apoptosis rate of PC12 cells, and Western blot to detect PCSK9, LRP1, PI3K, AKT, P-PI3K , P-AKT, NF-κB, Bcl-2, Bax, Caspase-9 and Caspase-3 expression, and ELISA detected Aβ content secreted by PC12 cells. Resultsox-LDL increased lipid accumulation and promoted apoptosis and Aβ secretion in PC12 cells, as well as increasing the expression of SREBP2 and PCSK9 and decreasing the expression of LRP1 in PC12 cells. pCsk9 siRNA could be inhibited through the PI3K/AKT pathway and the NF-κB-Bcl-2/Bax-Caspase-9/3 pathway to inhibit ox-LDL-induced apoptosis in PC12 cells while increasing Aβ secretion in PC12 cells. Conclusionox-LDL plays a bidirectional regulatory role in ox-LDL-induced apoptosis of PC12 cells by inducing an increase in PCSK9 expression and a decrease in LRP1 expression in PC12 cells, which in turn affects different signaling pathways downstream.

Objective To explore the therapeutic material basis and antitussive mechanism of Ganke Formula.Methods Ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS)technology was used to analyze and identify the components of Ganke Formula in serum.30 rats were randomly divided into control group,model group,experimental-L group,experimental-M group and experimental-H group,6 rats per group.Acute bronchitis rat model was established by smoke inhalation and cold stimulus.The experimental-L,-M,-H groups were respectively given 1.86,4.66,9.32 g·kg-1(crude drug/weight)dose of Ganke Formula per day by intragastric administration for 7 days.The control group and model group were given the equal amount of normal saline.The contents of interleukin-1β(IL-1β)and tumor necrosis factor-α(TNF-α)in rat lung tissue were determined by enzyme-linked immunosorbent assay.The expressions of phosphatidylinositol 3-kinase(PI3K)and phosphorylated protein kinase B(p-Akt)in lung were detected by Western blotting.Results Twenty-six absorbed components have been identified by UPLC-Q-TOF/MS.The contents of IL-1β in control group,model group,experimental-M,-H group were(57.80±7.67),(186.48±8.50),(166.05±9.90)and(143.19±6.31)pg·mL-1;TNF-α contents were(47.14±8.55),(316.22±9.49),(68.93±7.94)and(65.93±7.10)pg·mL-1;the relative expression levels of PI3K in lung tissues were 0.38±0.05,0.97±0.10,0.68±0.15 and 0.56±0.10;the relative expression levels of p-Akt were 0.34±0.14,0.93±0.05,0.63±0.16 and 0.49±0.14,respectively.Compared with the model group,the above indicators in the experimental-H group and control group were statistically different(P＜0.01 or P＜0.05).Conclusion Ganke Formula can intervene in the expression of inflammatory and immune regulatory factors by regulating PI3K/Akt signaling pathway,improve airway inflammation,and thus exert cough relieving effects.

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 understand the commercial homosexual behavior characteristics of men who have sex with men (MSM) and the factors associated with unprotected anal intercourse (UAI) in this population, and provide reference for the development of intervention strategy in MSM.Methods:Men who were aged ≥16 years and had anal sex with men in the past 6 months were recruited through internet in Fuzhou from January to December 2023 for a cross-sectional study with a sample size of 283. Multivariate logistic regression model was used to analyze the factors associated with the incidence of UAI in the past 6 months in MSM. The SPSS 25.0 software was used for statistical analysis.Results:In 4 484 MSM, the proportion of those with commercial homosexual behaviors was 9.59% (430/4 484), the average age was (27.00±9.07) years. In the MSM with commercial homosexual behaviors, 70.00% (301/430) had anal sex in the past one week, and 43.02% (185/430) had anal sex with more than 10 partners in the past 6 months. The proportion of MSM with UAI was 75.58% (325/430) in the past 6 months. The results of multivariate analysis showed showed that in MSM with commercial homosexual behaviors in the past 6 months, compared with those who were students, age >18 years at the first sexual intercourse, had not anal sex in the past one week, and anal sex with less than 10 partners in the past 6 months, the risk for UAI was higher in those who were not students (a OR=1.99,95% CI:1.18-3.36), those who were aged ≤18 years at first sexual intercourse sex (a OR=2.04,95% CI:1.26-3.29), those who had anal sex in the past one week (a OR=2.04,95% CI:1.25-3.33), and those who had anal sex with more than 10 partners in the past 6 months (a OR=1.97,95% CI:1.16-3.35). Conclusions:The risk for UAI was high in MSM with commercial homosexual behaviors in Fuzhou, so it is necessary to improve the awareness of safe sex and promote sex with regular partners and condom use, and preventing drug abuse in MSM.