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.

ObjectiveTo establish a model that can quickly identify the aroma components in different parts of Nardostachys jatamansi， so as to provide a quality control basis for the market circulation and clinical use of N. jatamansi. MethodsHeadspace solid-phase microextraction-gas chromatography-mass spectrometry（HS-SPME-GC-MS） combined with Smart aroma database and National Institute of Standards and Technology（NIST） database were used to characterize the aroma components in different parts of N. jatamansi， and the aroma components were quantified according to relative response factor（RRF） and three internal standards， and the markers of aroma differences in different parts of N. jatamansi were identified by orthogonal partial least squares-discriminant analysis（OPLS-DA） and cluster thermal analysis based on variable importance in the projection（VIP） value >1 and P<0.01. The odor data of different parts of N. jatamansi were collected by Heracles Ⅱ Neo ultra-fast gas phase electronic nose， and the correlation between compound types of aroma components collected by the ultra-fast gas phase electronic nose and the detection results of HS-SPME-GC-MS was investigated by drawing odor fingerprints and odor response radargrams. Chromatographic peak information with distinguishing ability≥0.700 and peak area≥200 was selected as sensor data， and the rapid identification model of different parts of N. jatamansi was established by principal component analysis（PCA）， discriminant factor alysis（DFA）， soft independent modeling of class analogies（SIMCA） and statistical quality control analysis（SQCA）. ResultsThe HS-SPME-GC-MS results showed that there were 28 common components in the underground and aboveground parts of N. jatamansi， of which 22 could be quantified and 12 significantly different components were screened out. Among these 12 components， the contents of five components（ethyl isovalerate， 2-pentylfuran， benzyl alcohol， nonanal and glacial acetic acid，） in the aboveground part of N. jatamansi were significantly higher than those in the underground part（P<0.01）， the contents of β-ionone， patchouli alcohol， α-caryophyllene， linalyl butyrate， valencene， 1，8-cineole and p-cymene in the underground part of N. jatamansi were significantly higher than those in the aboveground part（P<0.01）. Heracles Ⅱ Neo electronic nose results showed that the PCA discrimination index of the underground and aboveground parts of N. jatamansi was 82， and the contribution rates of the principal component factors were 99.94% and 99.89% when 2 and 3 principal components were extracted， respectively. The contribution rate of the discriminant factor 1 of the DFA model constructed on the basis of PCA was 100%， the validation score of the SIMCA model for discrimination of the two parts was 99， and SQCA could clearly distinguish different parts of N. jatamansi. ConclusionHS-SPME-GC-MS can clarify the differential markers of underground and aboveground parts of N. jatamansi. The four analytical models provided by Heracles Ⅱ Neo electronic nose（PCA， DFA， SIMCA and SQCA） can realize the rapid identification of different parts of N. jatamansi. Combining the two results， it is speculated that terpenes and carboxylic acids may be the main factors contributing to the difference in aroma between the underground and aboveground parts of N. jatamansi.

Aim To investigate the effect of Toddalia asiatica(TA)on bone destruction in rheumatoid ar-thritis(RA)and its possible mechanism by network pharmacology and in vitro experiments.Methods The active components and targets of TA against RA bone damage were analyzed by network pharmacology.Mo-lecular docking was performed by using AutoDock and PyMOL software pairs.MC3T3-e1 cells were cultured in vitro,and the effect of Toddalia asiatica alcohol ex-tract(TAAE)on cell viability was detected by CCK-8,and appropriate drug concentration and intervention time were screened.The osteoblast model was induced by osteogenic induction medium,and the osteogenic differentiation was detected by ALP staining,activity detection and alizarin red staining.The expression of pathway-related proteins Wnt3a and β-catenin was de-tected by Western blot,and the pathway inhibitor DKK-1 was used to further verify whether TAAE regulated osteoblast differentiation through the Wnt/β-catenin signaling pathway.Results A total of 158 anti-RA bone destruction targets and 56 core targets were se-lected.The enrichment of KEGG signaling pathway mainly included cancer pathway,phosphatidylinositol 3-kinase/protein kinase B signaling pathway and cAMP signaling pathway.The results of CCK-8 showed that 1 g·L-1 TAAE could significantly improve cell survival rate.The results of ALP staining and ALP activity de-tection showed that TAAE could significantly increase the staining positive rate and ALP activity of cells in-duced by osteogenic induction medium.Western blot showed that TAAE could increase the expression of Wnt3a and β-catenin.The expression of these proteins decreased after DKK-1 inhibitors were used.Conclu-sion TAAE can regulate osteoblast differentiation through Wnt/β-catenin signaling pathway to treat os-teodestruction in rheumatoid arthritis.

Objective:To establish a general method for the simultaneous determination of hydroxyphenyl esters and quaternary ammonium bacteriostatic agents in eye drops.Methods:The chromatographic analysis was per-formed on an Agilent C18 column(4.6 mm ×250 mm,5 μm)with 1％triethylamine solution(pH adjusted to 5.0 with phosphoric acid)as mobile phase A and methanol as mobile phase B.Gradient elution was performed at col-umn temperature of 40 ℃.The detection wavelength was 214 nm,the flow rate was 1 mL·min-1,and the injec-tion volume was 20 μL.Results:Methylparaben,ethylparaben,propylparaben,butylparaben,benzalkonium chlo-ride and benzalkonium bromide were 0.11-559.0,0.10-513.0,0.10-258.8,0.11-270.5,1.07-537.0 and 1.03-512.8 μg·mL-1,respectively.The linear range was good(r＞0.999).The average recoveries of meth-ylparaben,benzalkonium bromide and benzalkonium chloride were 104.7％(RSD=1.3％),102.6％(RSD=1.1％)and 100.9％(RSD=1.1％),respectively.The contents of bacteriostatic agent in 100 batches of eye drops from 36 varieties of 12 enterprises were determined,and the accurate results were obtained.Conclusion:This meth-od provides a reference for the content quality control and safety evaluation of bacteriostatic agents in eye drops.

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 effect of cardiac shock wave therapy(CSWT)on ST deviation of electrocardiogram and myocardial perfusion imaging in coronary artery disease(CAD)patients.Methods CAD patients who received CSWT in Cardiology Department of Beijing Hospital from December 2016 to August 2022 were enrolled.Three months of CSWT were conducted with a total of 9 times shock wave treatment.Clinical data,myocardial perfusion imaging data and stress electrocardiogram data were collected.Myocardial perfusion score,electrocardiographic data were compared before and after CSWT.Results A total of 55 patients were finally enrolled.There were 43 male and 12 female patients with an average age of(67.45±8.96)years old.ST deviation on 12 leads of electrocardiogram did not show significant difference before and after CSWT.Myocardial perfusion imaging showed global stress perfusion score(P=0.031)and reverse perfusion score(P=0.024).Global rest ischemia score reduced after CSWT(P=0.034).Target stress perfusion score(P=0.002),target reverse perfusion score(P=0.002),target reverse ischemic area(P=0.001)were improved after CSWT.Conclusions CSWT may not influence ST deviation of electrocardiogram,but may improve myocardial ischemia in CAD patients,

Objective To propose an effective method for the determination of 2-chloroethanol(ethylene chlorohydrin,ECH)and ethylene glycol(EG)residues in disposable infusion sets sterilized by ethylene oxide(EO).Methods Extraction with the ratio of the mass of the disposable infusion set to the volume of the medium being 0.4 g/mL was carried out with the 8890B gas chromatograph with liquid injection,DB-WAX column and ethanol extraction medium,and quantitative determination of ECH and EG in disposable infusion sets were implemented after extraction at 37℃for 10 h.Results The method proposely was highly specific,and showed high linearity in the range of 1.25-100.00 μg/mL for both ECH and EG.The limits of detection were 0.31 and 0.11 μg/mL for ECH and EG,respectively,and the relative standard deviations(RSD)of the precision of ECH was in the range of 0.24％-2.03％and those of EG was in the range of 0.16％-0.87％.The average recoveries were 95.02％-100.58％for ECH and 99.15％-99.98％for EG.Conclusion The method proposed for the determination of ECH and EG residues gains advantages in easy operation,specificity,detection accuracy and reproducibility,and meets the requirements for the determination of ECH and EG residues in EO-sterilized disposable infusion sets.[Chinese Medical Equipment Journal,2024,45(10):31-36]

AIM:To investigate whether Miaoyao Tongfeng prescription(MTP)attenuates oxidative stress in-jury in gouty arthritis rats by regulating Kelch-like epicklorohydrin-related protein 1(Keap1)/nuclear factor E2-related fac-tor 2(Nrf2)signaling pathway.METHODS:Fifty male Sprague-Dawley rats were randomly divided into control group,model group,MTP group,Nrf2 inhibitor all-trans retinoic acid(ATRA)group and MTP+ATRA group.The 3%potassium oxonate solution(10 mL/kg)was injected intraperitoneally twice a day for 1 week,and then 0.2 mL sodium urate suspen-sion(25 g/L)was injected into the right knee joints to establish the gouty arthritis model.All rats were sacrificed 48 h af-ter modeling.Grades of swelling in the knee joints were evaluated,and HE staining was used to observe the pathological changes of knee joints.Serum levels of superoxide dismutase(SOD),malondialdehyde(MDA)and interleukin-1β(IL-1β)were detected using kits.The mRNA levels of Nrf2,Keap1,heme oxygenase-1(HO-1),IL-1β,NAD(P)H:quinone oxidoreductase 1(NQO1)in the synovial membrane of the knee joints were detected by qRT-PCR.Western blot was used to detect the expression of Nrf2,Keap1 and NQO1 in the synovial membrane of the knee joints.RESULTS:Compared with model group,MTP significantly reduced the degree of knee joint swelling,and attenuated the pathological injury of knee synovial membrane.It also inhibited the expression of MDA and IL-1β,but increased the expression of SOD.The mRNA expression of HO-1,and the mRNA and protein expression of Nrf2 and NQO1 in synovium were up-regulated,while the levels of IL-1β mRNA,Keap1 mRNA and Keap1 protein were down-regulated.CONCLUSION:Miaoyao Tongfeng prescription shows promise in the prevention and treatment of gouty arthritis through regulating Nrf2 and down-stream anti-oxidation genes.

Objective:To analyze the incidence and clinical phenotype of the concomitant extragenital malformations in the patients with female reproductive tract anomalies.Methods:A retrospective study was conducted using clinical data of hospitalized patients diagnosed with uterine, cervical, or vaginal malformations from January 2003 to December 2022 in Peking Union Medical College Hospital. The malformations were classified according to American Society for Reproductive Medicine müllerian anomalies classification 2021, and in each type, the incidence and specific manifestations of concomitant extragnital malformations were analyzed.Results:A total of 444 patients were included. The overall incidence of concomitant extragenital malformations was 43.5% (193/444), including urinary system, skeletal system, and other system malformations. Renal malformations on the obstructed side were present in all patients with oblique vaginal septum syndrome (100.0%, 78/78). The total incidence of concomitant extragnital malformations was as high as 8/11 in uterus didelphys, 43.5% (10/23) in unicornuate uterus, 33.6% (79/235) in Mayer-Rokitansky-Küster-Hauser syndrome, 18.8% (6/32) in septate uterus and 18.5% (12/65) in cervical agenesis. Urinary system malformations (30.6%, 136/444) and skeletal system malformations (13.5%, 60/444) were the most common concomitant malformations in all types, in which, unilateral renal agenesis and scoliosis were the most common.Conclusions:Urinary and skeletal system malformations are important features of female reproductive tract anomalies. Urologic ultrasonography and spinal roentgenogram are recommended for all patients with female reproductive tract anomalies.

Aim To investigate the regulatory role and mechanism of resveratrol in inhibiting autophagy and promoting apoptosis in choroidal melanoma cells. Methods Choroidal melanoma cells (MUM2B) were divided into control and experimental groups, and treated with different concentrations of resveratrol (0, 10, 20,40,60,80 μmol ·L