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 evaluate the efficacy of modified femoral neck osteotomy(mFNO)in the surgical treatment of patients with ankylosing spondylitis(AS)and severe spinal kyphosis combined with hip flexion contracture.Methods:A retrospective analysis was conducted on 61 AS patients(103 hips)with spinal kyphosis and hip flexion contracture who underwent pedicle subtraction osteotomy(PSO)and total hip arthroplasty(THA)from January 1,2019 to November 15,2023.Data on mFNO operation time,blood loss,preoperative and postoperative values of the angle of the trunk and lower limb(ATL),hip passive range of motion(ROM),visual analogue scale(VAS),and incidence of in-hospital compli-cations were recorded.Statistical analysis was performed using paired-samples t test.P＜0.05 was con-sidered statistically significant.Results:The study ultimately included 10 cases,9 males and 1 female,with an average age of(41.30±9.03)years.These patients underwent surgery for a total of 52 times,including 19 hips both receiving mFNO and THA,and 14 times PSO.The average operation time for nine bilateral mFNO was(133.11±34.81)min,with blood loss of(433.33±187.10)mL.A unilateral mFNO took 60 min with 200 mL of blood loss.The preoperative ATL of 19 hips was 40.37°±13.66°,and the postoperative ATL value was 88.47°±12.46°(P＜0.05).The preoperative VAS score was 0,while the postoperative VAS score was 5.95±1.51(P＜0.05).The preoperative hip extension ROM was 37.37°±18.13°,while the postoperative hip extension ROM was-4.95°±21.24°(P＜0.05).Hip flexion ROM improved from 37.37°±18.13° to 50.79°±20.36° after FNO(P＜0.05).There were three cases of in-hospital complications(3/52,5.67％):One case of postoperative atelectasis fol-lowing PSO(1/52,1.92％),one greater trochanter fracture identified during THA(1/52,1.92％),and one early dislocation post-THA(1/52,1.92％).Conclusion:mFNO significantly improves the ATL in AS patients with severe spinal kyphosis combined with hip flexion contracture,facilitating PSO and THA surgeries.

Objective:To understand the whole genome and genetic evolution characteristics of the first epidemic influenza A (H3N2) viruses in Wuxi from 2022-2023.Methods:Real time fluorescence quantitative RT-PCR method was used to perform typing on respiratory samples of influenza cases. Virus isolation was performed on samples with positive nucleic acid of subtype A H3N2 influenza virus detected. After cell culture, nucleic acid was extracted from strains with red blood cell agglutination test (HA) ≥ 1∶8, whole genome sequence was amplified, library was constructed, and computer sequencing was performed using MiSeq sequencer. Using NC_007366.1 as reference strain, the data were analyzed using CLC Genomics Workbench (Version 23) software. The phylogenetic tree was constructed using MEGA 7.0 software, and the N-glycosylation sites were predicted by NetNGlyc 1.0 Server software.Results:The nucleotide homology and amino acid homology among 35 strains of influenza A H3N2 virus from 2022 to 2023 were 96.4%-100% and 95.2%-100%, respectively. The 16 epidemic strains in 2022 belong to the 3C.2a1b.2a.1a evolutionary branch, while the 19 epidemic strains in 2023 belong to the 3C.2a1b.2a.2a.3a.1 evolutionary branch. There are 7 differences in the nucleotide sequence of the HA gene between the 2022 epidemic strain and the corresponding vaccine strain, sharing 15 mutation sites; There are 28 differences in the nucleotide sequence of the HA gene between the 2023 epidemic strain and the corresponding vaccine strain, sharing 17 mutation sites. The HA genes of 35 epidemic strains all lack N-glycosylation site 61: NSS, while in 2023, the HA genes of 19 epidemic strains added N-glycosylation site 110: NSS.Conclusions:The HA and NA genes of influenza A H3N2 virus in 2022 and 2023 belong to two evolutionary branches, respectively, and both show specific amino acid site changes compared to the corresponding vaccine strains. The antigen matching between the 2022 epidemic strain and the vaccine strain is relatively good, while there is a risk of low antigen matching between the 2023 epidemic strain and the vaccine strain.

Objective:To analyze the clinical characteristics and all-cause mortality influencing factors of patients with Keshan disease.Methods:Clinical data of patients with Keshan disease from Keshan disease areas in Sichuan Province and Yunnan Province were collected and retrospectively analyzed for clinical characteristics and survival status during regular follow-up. According to the survival status of patients, the survey subjects were divided into a survival group and a death group. All-cause mortality (referring to the death caused by various reasons throughout the follow-up period) was used as the study endpoint. Kaplan-Meier (K-M) survival curve analysis and log-rank χ 2 test were performed, univariate and multivariate Cox regression analysis were used for all-cause mortality factor analysis. Results:A total of 176 patients with Keshan disease were collected, including 92 cases in Sichuan Province and 84 cases in Yunnan Province. Among all the patients, there were 105 males, accounting for 59.66%, and 71 females, accounting for 40.34%. The age was (53.89 ± 13.19) years old. Thirty-five cases died from all causes, with a mortality rate of 19.89%. There were significant differences in age ( t = 2.09, P = 0.038), New York Heart Association (NYHA) cardiac function grading (χ 2 = 14.62, P < 0.001) and ventricular premature contraction (χ 2 = 6.82, P = 0.009) between the survival group and the death group. K-M survival curve analysis showed that patients with Keshan disease complicated by premature ventricular contraction and high NYHA cardiac function grading (Ⅲ and Ⅳ) had higher all-cause mortality (log-rank χ 2 = 8.72, 22.49, P < 0.05). Univariate Cox regression analysis showed that NYHA cardiac function grading and ventricular premature contraction ( HR = 3.09, 2.71, P < 0.05) were predictive influencing factors for all-cause mortality in patients with Keshan disease. Multivariate Cox regression analysis showed that NYHA cardiac function grading ( HR = 6.57, P = 0.002) and ventricular premature contraction ( HR = 2.98, P = 0.050) were independent factors for all-cause mortality in patients with Keshan disease. Conclusions:Among 176 patients with Keshan disease, the number of patients with poor cardiac function (NYHA cardiac function grading Ⅲ and Ⅳ) and arrhythmia is high. NYHA cardiac function grading and ventricular premature contractions are independent influencing factors for all-cause mortality in patients with Keshan disease.

Objective:To study the distribution of species type, biotype and genotype of human Brucella isolated and identified in Nanjing. Methods:A total of 89 strains of human Brucella were collected from microbiology laboratories of three sentinel hospitals in Nanjing from 2017 to 2022. The species type was identified using biological methods and Brucella nucleic acid detection (BCSP31-PCR and AMOS-PCR). Further biotyping of Brucella melitensis isolates was conducted by serological results of A and M factors. Meanwhile, genotype analysis was performed using multiple-locus variable number tandem repeat analysis (MLVA), multilocus sequence typing (MLST) and single nucleotide polymorphism (SNP). Results:From 2017 to 2022, 89 strains of Brucella isolated and identified in Nanjing were all Brucella melitensis. Among them, Brucella melitensis biotype 3 accounted for 82.02% (73/89), and biotype 1 accounted for 17.98% (16/89). MLVA typing showed that 89 strains of Brucella melitensis belong to the "Eastern Mediterranean" cluster and could be divided into 50 MLVA genotypes; among which panel 1 had 3 genotypes, namely Type 42 (84.27%, 75/89), Type 63 (8.99%, 8/89) and Type 43 (6.74%, 6/89). The results of MLST-9 and MLST-21 were both ST8, and the core genome multilocus sequence typing (cgMLST) classified 89 strains into 11 genotypes. SNP analysis revealed a total of 4 013 SNP loci, with SNPs ranging from 0 to 409 across different strains, involving 59 SNP genotypes. Conclusions:The human Brucella strains isolated and identified in Nanjing are all Brucella melitensis, mainly biotype 3. The MLVA cluster is the "Eastern Mediterranean" cluster. The traditional MLST-9 and MLST-21 typing results are all ST8 type, while cgMLST divides all the strains into 11 genotypes with higher resolution.

Objective To understand the prevalence characteristics of influenza and changes of influenza virus strains,and provide reference for the prevention and control of influenza in the province.Methods Surveillance da-ta about influenza in Hunan Province from 2014 to 2023 were exported from China Influenza Surveillance Informa-tion System.Differences in the percentage of influenza-like illness(ILI)cases(percentage of influenza-like cases[ILI％]in outpatient and emergency department visits)among different years and different populations,as well as the positive rate of influenza virus in ILI specimens were compared.Results From 2014 to 2023,over 2.65 million cases of ILI were reported,with an ILI％of 4.70％.ILI％among different years presented statistically significant differences(P＜0.001).People aged 0-14 years old were the main population with ILI,accounting for 82.90％.The positive rate of influenza virus in ILI specimens was 14.14％,the positive rate of influenza virus among diffe-rent years and age groups were both significantly different(both P＜0.001).The main prevalent influenza strains from 2014 to 2023 included types A(H1N1),A(H3N2),B(Victoria),and B(Yamagata),alternating among di-fferent years.However,type B(Yamagata)strains were not detected from 2020 to 2023.There were basically two influenza prevalence seasons every year,namely winter-spring and summer.Conclusion People＜15 years old are the main population of influenza,and the prevalence peaks are in winter-spring and summer.From 2021 to 2023,the prevalence alternates mainly among 3 types:A(H1N1),A(H3N2),and B(Victoria).

Objective To explore the clinical efficacy of double beam double tunnel enhanced reconstruction technique in the treatment of knee anterior cruciate ligament(ACL)training injuries.Methods Twenty-nine cases of ACL injury of knee joint from January 2021 to December 2021 were retrospectively analyzed.All the cases were underwent ligament reconstruc-tion surgery.Cases were grouped by surgical technique:there were 14 patients in conventional reconstruction group,including 13 males and 1 female,aged from 22 to 31 years old with an average of(27.07±7.28)years old,autogenous hamstring tendon was used for ligament reconstruction.There were 15 patients in the enhanced reconstruction group,including 13 males and 2 females,aged from 25 to 34 years old with an average of(29.06±4.23)years old,double tunnel ligament reconstruction,the autogenous hamstring muscle was used as the anteromedial bundle,and the posterolateral bundle was replaced by a high-strength line.The difference between knee tibial anterior distance,Lysholm score,International Knee Literature Committee(IKDC)subjective score,Tegner motor level score and visual analog scale(VAS)at 6th and 12th months after the surgery,limb symmetry index(LSI)were recorded at the last follow-up and surgery-related adverse effects during follow-up.Results All patients were followed up,ranged from 13 to 15 months with an average of(13.7±0.8)months.There were no serious adverse reactions related to surgery during the period.There was no statistical difference between the preoperative general data and the observation index of the two groups(P＞0.05).The difference in tibial anterior distance at 6 and 12 months in the enhanced re-construction group(1.45±0.62)mm and(1.74±0.78)mm which were lower those that in the conventional reconstruction group(2.42±0.60)mm and(2.51±0.63)mm(P＜0.05).There was no significant difference in postoperative Lysholm score,Tegner motor level score,IKDC score,VAS,and limb symmetry index at the last follow-up(P＞0.05).Conclusion The enhanced recon-struction technique can more effectively maintain the stability of the knee joint and has no significant effect on the postoperative knee joint function compared with the traditional ligament reconstruction technique.The short-term curative effect is satisfac-tory,and it is suitable for the group with high sports demand.

Objective To explore the effectiveness and safety of percutaneous coronary artery shock wave balloon angioplasty(IVL)under the guidance of intravascular ultrasound(IVUS)for the treatment of severe calcification lesions in the left main artery(LM).Methods A total of 26 patients with severe LM(mouth,body,bifurcation)calcification admitted to Jiangnan University Affiliated Hospital from October 2022 to April 2024 were included,with an average age of 72.0(61.8,75.4)years.Under the guidance of IVUS,IVL was used for pre-treatment of calcified lesions,followed by percutaneous coronary intervention(PCI)with stent/drug balloon implantation.All patients were evaluated using IVUS before and after the use of IVL and after PCI.And compare the IVUS intracavity related data before and after treatment[plaque burden(PB)、minimum lumen area(MLA)、minimum lumen diameter(MLD)]and calcification fracture number,minimum stent area(MSA),stent expansion coefficient(expansion,EXP),etc.Results There were 26 patients(2 with opening lesions,7 with body lesions,and 17 with bifurcation lesions at the end of the main trunk),including 7 with stable angina pectoris(SAP),10 with unstable angina(UA),4 with acute ST-segment elevation myocardial infarction(STEMI),and 5 with non ST-segment elevation myocardial infarction(NSTEMI).The PB at the most severe site of calcification decreased by 79.50(76.00,83.75)％compared to 80.00(76.00,83.75)％after IVL(P=0.001),MLA increased by 3.39(3.14,3.68)mm2 compared to 3.38(3.14,3.67)mm2 after IVL(P=0.039),MLD increased by 3.21(3.07,3.30)mm compared to 3.20(3.07,3.30)mm after IVL(P=0.024),and there was 100％calcification rupture(1/2 cases,2/9 cases,≥3/15 cases).The stent/drug ball was successfully implanted 100％,with EXP of(89.15±4.42)％and an MSA of 7.20(6.46,7.45)mm2.No adverse events such as death,angina or recurrent myocardial infarction occurred during the 3 months follow-up after surgery.Conclusions After evaluation by IVUS and pre-treatment with IVL,PCI was successfully completed for severe calcification lesions in LM,and IVL can be used as an option for the treatment of severe calcification in LM.

Here,5 important pathogens carried by ticks in Maanshan City,Anhui Province,China were identified.In to-tal,642 ticks were collected from 13 villages around Maanshan City and identified by morphological and mitochondrial COI genes.The 16S rRNA gene of Francisella tularensis,ssrA gene of Bartonella,16S rRNA,ompA and ompB genes of Rickett-sia,16S rRNA and gltA genes of Anaplasma,and groEL and rpoB genes of Coxiella were sequenced.Reference sequences were retrieved from a public database.Phylogenetic trees were constructed with MEG A1 1.0 software.In total,36 Rickettsiae isolates were detected in 640 Haemaphysalis longicornis ticks,which included 20 isolates of Rickettsia heilongjian-gensis,16 of Candidatus Rickettsia jingxinensis,2 of Ana-plasma bovis,and 186 of Coxiella-like endosymbiont.R.hei-longjiangensis HY2 detected in this study and Anhui B8 strain,Ca.R.jingxinensis QL3 and those from Shanxi Prov-ince and Jiangsu Province,A.bovis JX4 and those from Shanxi Province were clustered on the same branch.Overall,17 ticks had combined infections and none of the 5 bacteria were detected in two Amblyomma testudinarium ticks.This is the first report of Ca.R.jingxinensis detected in H.longicornis ticks from Anhui Province.It is recommended that the two types of Rickettsia that cause spotted fever and A.bovis should be reported to local health authorities to initiate appropriate prevention and control measures.

Objective:To optimize the technical parameters related to the preparation of novel frozen human platelets and formulate corresponding protocol for its preparation.Methods:Novel frozen human platelets were prepared with O-type bagged platelet-rich plasma(PRP),the key technical parameters(DMSO addition,incubation time,centrifugation conditions,etc.)of the preparation process were optimized,and the quality of the frozen platelets was evaluated by routine blood tests,apoptosis rate,platelet activation rate and surface protein expression level.Results:In the preparation protocol of novel frozen human platelets,the operation of centrifugation to remove supernatant was adjusted to before the procedure of platelets freezing,and the effect of centrifugation on platelets was minimal when the centrifugation condition was 800 xg for 8 min.In addition,platelets incubated with DMSO for 30 min before centrifugation exhibited better quality after freezing and thawing.The indexes of novel frozen human platelets prepared with this protocol remained stable after long-term cryopreservation.Conclusion:The preparation technique of novel frozen human platelets was established and the protocol was formulated.It was also confirmed that the quality of frozen platelets could be improved by incubating platelets with DMSO for 30 min and then centrifuging them at 800 ×g for 8 min in the preparation of novel frozen human platelets.