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 understand the surveillance situation of poliovirus in Guangzhou from 2011 to 2024, and to further strengthen polio surveillance and ensure the continued maintenance of a polio-free status. Methods An analysis was conducted on the discovery and investigation results of six cases of vaccine-derived poliovirus (VDPV) detected in Guangzhou. Results A total of 6 VDPV incidents were reported in Guangzhou from 2011 to June 2024, among which 5 incidents were from sewage sample testing in the Liede Sewage Treatment Plant in Guangzhou, all of which were confirmed as VDPV, with 1 for type I, 1 for type II, and 3 for type III. In addition, one confirmed HFMD case was identified as a type VDPV II carrier. No presence of any wild poliovirus (WPV), VDPV cases, or circulating VDPV (cVDPV) was reported. Conclusion Guangzhou City has maintained a high level of vigilance and effectiveness in the monitoring and prevention of polio. Continuously strengthening the construction of the polio monitoring network, optimizing vaccination strategies, and comprehensively improving public health awareness are still the focus of the prevention and control work in the future.

Aim To study the active ingredients and mechanism of action of Xinkeshu tablets against myo-cardial ischemia by network pharmacology and ze-brafish model.Methods The anti-myocardial ische-mia activity of Xinkeshu tablets was evaluated by iso-prenaline hydrochloride(ISO)-induced zebrafish myo-cardial ischemia model and H2O2-induced H9c2 dam-age model.The active ingredients of Xinkeshu tablets were retrieved using databases such as TCMSP.The potential targets were predicted by PharmaMapper data-base.Myocardial ischemic disease targets were searched by OMIM database.The potential therapeutic targets of Xinkeshu tablets against myocardial ischemia were analyzed.GO and KEGG enrichment analysis were conducted on core targets.The active ingredients were verified by zebrafish and cell model.qRT-PCR was used to detect the expression of key targets.Re-sults Xinkeshu tablets could significantly alleviate ISO-induced pericardial edema and bradycardia.It al-so could increase sinus venous-bulb aortic(SV-BA)distance and improve the cell viability.The 30 poten-tial active ingredients of Xinkeshu tables mainly acted on 30 core targets,including ALB,AKT1 and MAPK1,to regulate 627 GO items,including protein phosphorylation,negative regulation of apoptosis and positive regulation of PI3K signal transduction.KEGG results showed that 117 signaling pathways,including PI3K/Akt,FOXO and Ras,exerted anti-myocardial ischemia effect.Salvianolic acid A,lithospermic acid,rosmarinic acid,salvianolic acid D,salvianolic acid B,ginsenoside Rg2,hyperoside,3'-methoxypuerarin,3'-hydroxypuerarin and ginsenoside Rg1 could alleviate ISO-induced zebrafish myocardial ischemia and im-prove the cell viability.Xinkeshu tablets could upregu-late the expression of genes such as ras and akt1,and downregulate the expression of genes such as mapk1 and mapk8.Conclusion The active ingredients,in-cluding salvianolic acid A in Xinkeshu tablets,exert anti-myocardial ischemia effects by targeting targets,such as AKT1,MAPK1,and regulating signaling path-ways,such as PI3K/Akt,MAPK and Ras.

The distribution of Ixodes and Ana plasma carried by Ixodes ticks in Anhui Province was clarified as reference for prevention and control of anaplasmosis.In total,630 hard ticks were collected from Jinzhai County,Hanshan County,Jing-de County and Chaohu City in Anhui Province from April to August 2023.Ticks were identified by morphological analysis and 16S rRNA sequencing.Nested PCR with Anaplasma species-specific primers were used to detect 16S rRNA of Anaplasma spe-cies carried by ticks.A phylogenetic tree was constructed using MEGA11.0 software.Of the identified ticks,18.8％(18/96)were Rhipicephalus microplus and 81.2％(78/96)were Haemaphysalis longicorni in Jinzhai County of Anhui Province,all were H.longicorni in Hanshan County and Chaohu City,while the main species in Jingde County was R.microplus.The posi-tive rate of Anaplasma carried by H.longicornis was 30.9％(102/330),which included A.bovis at 1.8％(6/330),A.phagocytophilum at 21.8％(72/330)and uncultured Anaplasma species at 7.3％(24/330).R.microplus was positively cor-related to A.bovis(13.6％,18/132).The uncultured Anaplasma species was mainly detected in host-free ticks.A.phagocy-tophilum was detected in 24.4％of parasitic ticks and 15.8％of host-free ticks.The positive rates of host-free and parasitic ticks were 19.9％and 17.8％,respectively.These results show that H.longicornis and R.microplus were the dominant ticks in several counties of Anhui Province.H.longicornis and R.microplus as well as free and parasitic ticks all carried Anaplas-ma.

Objective:To explore the levels of regulatory T cells(Tregs)and cytokines IL-35,TGF-β and IL-10 in peripheral blood of hemophilia A(HA)patients with F Ⅷ inhibitor and their clinical significance.Methods:43 HA patients admitted to the Hematology Department of the Affiliated Hospital of North China University of Science and Technology from October 2019 to December 2020 were selected,including 6 cases with F Ⅷ inhibitor and 37 cases without FⅧ inhibitor.In addition,20 healthy males who underwent physical examinations were selected as healthy controls.Flow cytometry was used to detect the levels of CD4+CD25+CD127-Tregs in peripheral blood of the HA patients and healthy controls,and ELISA assay was used to detect the expression levels of IL-35,TGF-β and IL-10 in serum,and their differences between different groups were compared.Results:Compared with the healthy control group,the level of Tregs in HA patients was decreased,and the level of Tregs in the FⅧ inhibitor positive group was the lowest,the difference was statistically significant(P＜0.05).There was no significant difference in the expression level of Tregs in HA patients of different severity levels.The serum IL-35,TGF-β,and IL-10 levels in both FⅧ inhibitor negative and positive groups were significantly lower than those in healthy control group,and those in FⅧ inhibitor positive group were significantly lower than those in FⅧ inhibitor negative group(all P＜0.05).Conclusion:The decrease of Tregs,IL-35,TGF-β,and IL-10 levels in HA patients may be related to the formation of FⅧ inhibitors.

Oligoasthenozoospermia(OAS)is the main factor for male infertility,and the cause and pathogenesis of the disease remain unknown.Emerging data indicate that cellular autophagy is closely correlated with male reproduction,especially the biosynthet-ic and catabolic processes of spermatogenesis and sperm maturation.Nonetheless,it is not yet clear whether autophagy plays a protec-tive or a harmful role in these processes.Traditional Chinese medicine(TCM)has exhibited a definite therapeutic effect on OAS,and its action mechanism might be closely associated with cellular autophogy,and its related markers and pathways.This article systemati-cally reviews the role of cellular autophagy in spermatogenesis and sperm maturation,as well as the therapeutic effect of TCM on OAS by regulating the process of autophagy,aiming to gain a deeper insight into the potential mechanism of TCM acting on OAS and provide some references for further improvement of its clinical efficacy.

With the change of lifestyle,the obese population is gradually increasing,and the prevalence of type 2 diabetes mellitus(T2DM)is increasing year by year,while the age of onset is declining year by year.Diabetic retinopathy(DR),as one of the common complications of T2DM,has a serious impact on the quality of life of patients.At present,there is no way to predict and completely stop the progression of DR.Studies have shown that vitamin D supplementation can effectively alleviate DR in vitamin D deficiency patients,which is expected to become a new idea and method to predict and treat DR.This article-reviews the role of vitamin D in the occurrence and development of DR,as well as its therapeutic effect and mechanism on DR,in order to provide a basis for the application of vitamin D supplementation in the prevention and treatment of DR.

A 5-year-old girl was admitted due to one episode of melena and one episode of hematemesis.Upon admission,gastroscopy revealed esophageal and gastric varices.Abdominal CT scan,MRI,and color Doppler ultrasound suggested cirrhosis,intrahepatic bile duct dilation,and bilateral kidney enlargement.Genetic testing identified compound heterozygous mutations in the PKHD1 gene:c.2264C>T(p.Pro755Leu)and c.1886T>C(p.Val629Ala).The c.2264C>T(p.Pro755Leu)mutation is a known pathogenic variant with previous reports,while c.1886T>C(p.Val629Ala)is a novel mutation predicted to have pathogenic potential according to Mutation Taster and PolyPhen2.The child was diagnosed with autosomal recessive polycystic kidney disease.In children presenting with gastrointestinal bleeding without obvious causes,particularly those with liver or kidney disease,consideration should be given to the possibility of autosomal recessive polycystic kidney disease,and genetic testing should be conducted for definitive diagnosis when necessary.

Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

In order to solve the problem of resistance of Pseudomonas aeruginosa to multiple antibiotics, it is an effective way to find inhibitors of P. aeruginosa efflux pump. In this study, 15 new ornithine peptidomimetic derivatives were designed and synthesized by changing the side chain structure of natural amino acids with PAβN, a dipeptide efflux pump inhibitor, and their synergic activity with aztreonam, a monocyclic β-lactam antibiotic, against P. aeruginosa was evaluated. Among them, the representative compound 12b not only enhanced the antibacterial activity of β-lactam antibiotics aztreonam, ceftazidime and meropenem, but also significantly enhanced the antibacterial action of macrolide antibiotics clarithromycin, showing a broad-spectrum synergic sensitization effect. In addition, compound 12b also has a good safety. Preliminary mechanisms suggest that 12b works by directly targeting the efflux transporter MexB. These results provide a new lead compound for the development of a new class of efflux pump inhibitors against P. aeruginosa.