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 investigate the effect of liquid-liquid phase separation(LLPS)of YTH domain family protein 2(YTHDF2)on the sodium arsenite-induced malignant transformation of skin cells,providing a new intervention target for the prevention and control of sodium arsenite-induced carcinogenesis.Methods The HaCaT cell model of malignant transformation was constructed by continuous treatment with 1 μmol/L sodium arsenite for 22 weeks,including cells with normal YTHDF2 LLPS(YTHDF2-wt)and cells with inhibited YTHDF2 LLPS(YTHDF2-mut).Confocal microscopy was employed to observe and characterize the LLPS droplets formed by YTHDF2 during sodium arsenite-induced malignant transformation of skin cells.Cell proliferation,scratch healing,and colony formation assays were performed to detect malignant phenotypes.Western blotting,quantitative reverse transcription PCR,and immunofluorescence experiments were conducted to examine the effects of YTHDF2 LLPS on the mRNA and protein levels of phosphatase and tensin homolog deleted on chromosome ten(PTEN)during sodium arsenite-induced malignant transformation of skin cells.Results After 4 weeks of sodium arsenite treatment,LLPS droplets of YTHDF2 appeared in YTHDF2-wt cells,and the number of droplets gradually increased as the treatment time was prolonged(F=35.252,P<0.001),while no phase-separated droplets were observed in YTHDF2-mut cells.Compared with YTHDF2-mut cells,YTHDF2-wt cells showed enhanced proliferation at the time points of 48 h(t=3.654,P=0.006)and 72 h(t=5.458,P<0.001)after 22 weeks of sodium arsenite treatment.The scratch healing rate of YTHDF2-wt cells was increased at the 8th(t=12.137,P<0.001)and 22th(t=4.484,P=0.011)weeks of sodium arsenite treatment.The number of colonies formed by YTHDF2-wt cells was higher at the 4th(t=3.365,P=0.027),8th(t=5.580,P=0.005),and 22th(t=3.328,P=0.029)weeks of sodium arsenite treatment.Compared with YTHDF2-mut cells,YTHDF2-wt cells showed down-regulated protein(t=-3.119,P=0.036)and mRNA(t=4.051,P=0.015) levels of PTEN after 22 weeks of sodium arsenite treatment.Immunofluorescence results showed that after 4 weeks of sodium arsenite treatment,YTHDF2 LLPS droplets in YTHDF2-wt cells were localized to stress granules,translation-related membrane-less organelles.Conclusions During sodium arsenite-induced malignant transformation of skin cells,YTHDF2 undergoes LLPS and localizes to stress granules,translation-related membrane-less organelles.YTHDF2 LLPS participates in sodium arsenite-induced malignant transformation of skin cells by down-regulating the mRNA level of the key tumor suppressor PTEN.
Arsenites/toxicity* ; Sodium Compounds/toxicity* ; Humans ; Cell Transformation, Neoplastic/drug effects* ; PTEN Phosphohydrolase/metabolism* ; Cell Proliferation ; Skin/cytology* ; RNA-Binding Proteins ; Skin Neoplasms/chemically induced* ; Cell Line

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

AIM To evaluate the quality of Rubi Fructus.METHODS UPLC-Q-TOF-MS/MS was adopted in the component identification,after which the HPLC fingerprints were established,cluster analysis,principal component analysis and orthogonal partial least squares discriminant analysis were used for chemical pattern recognition.and the contents of chlorogenic acid,ferulic acid,ellagic acid,isoquercitrin,kaempferol-3-O-rutinoside,astragalin,tiliroside quercetin,kaempferol were determined.RESULTS Total 34 constituents were identified.There were 19 common peaks in the fingerprints for 31 batches of medicinal materials with the similarities of more than 0.8.Wild varieties and cultivated varieties,and medicinal materials from different producing areas could be distinguished;4 principal components demonstrated the accumulative variance contribution rate of 84.142％;8 differential components were screened,2 of which were ellagic acid and astragalin.Ellagic acid and astragalin displayed higher contents in the wild varieties than those in the cultivated varieties(P＜0.05,P＜0.01).CONCLUSION UPLC-Q-TOF-MS/MS,HPLC fingerprints combined with content determination can be used for the quality control of Rubi Fructus.

AIM To establish a UPLC-MS/MS method for the simultaneous content determination of isofraxidin,saikosaponin c,ginsenoside Re,puerarin,rosmarinic acid,praeruptorin A,daidzein,baicalin and 5-O-methylvisammioside in Chaige Changyuan Mixture.METHODS The analysis was performed on a 35 ℃ Titank C18 column(100 mm×2.1 mm,3 μm),with the mobile phase comprising of acetonitrile-0.1％formic acid flowing at 0.3 mL/min in a gradient elution manner,and electron spray ionization source was adopted in positive and negative ion scanning with multiple reaction monitoring mode.RESULTS Nine constituents showed good linear relationships within their own ranges(r≥0.999 0),whose average recoveries were 84.08％-115.40％with the RSDs of 0.21％-4.47％.CONCLUSION This efficient,simple,sensitive and specific method can be used for the quality control of Chaige Changyuan Mixture.

Objective:To explore the impact of the stimulator of interferon genes(STING)-interferon regulatory factor 3(IRF3)pathway on the senescence of rapid pacing HL-1 myocytes.Methods:HL-1 cells were divided into five groups: the control group(HL-1 cells without any treatment), pacing group(HL-1 cells paced for 48 hours), STING siRNA group(HL-1 cells paced for 48 hours and transfected with STING siRNA), NC siRNA group(HL-1 cells paced for 48 hours and transfected with NC siRNA), and H151 inhibitor group(HL-1 cells paced for 48 hours with the addition of 1 μmol/L STING inhibitor H151). Mitochondrial membrane potential was assessed in control and pacing group cells, and mitochondrial MitoTracker and TFAM co-localization staining was performed on these cells.Cellular senescence was evaluated using β-galactosidase staining in each group, and the positive rate of cellular senescence was observed and calculated.Western blotting was employed to detect the expression levels of STING, IRF3, P-IRF3, P16, P21, and P53 proteins in all groups.Immunofluorescence was utilized to examine the expression distribution of STING and P21 across the various groups.ELISA was performed to measure the concentrations of interleukin(IL)-1β, IL-6, and IL-8 in the cell supernatants from each group as part of the senescence-associated secretory phenotype(SASP).Results:Compared with the control group, the ratio of mitochondrial JC-1 multimer to monomer was significantly decreased in the pacing group( t=16.42, P<0.05), the co-localization of mitochondrial MitoTracker and TFAM in the cells was significantly weakened, the proportion of cells with positive cellular senescence-associated β-galactosidase staining significantly increased in the pacing group, the expression levels of STING, P-IRF3/IRF3, P16, P21, and P53 proteins were significantly elevated in the pacing group, and the concentrations of IL-1β, IL-6, and IL-8 in the cell supernatants were markedly increased.Compared with the pacing group, the proportion of cells with positive cellular senescence-associated β-galactosidase staining decreased in the STING siRNA group and H151 inhibitor group ( F= 18.13, P<0.05), the expression levels of STING, P-IRF3/IRF3, P16, P21, and P53 were reduced in the STING siRNA group and H151 inhibitor group ( F=16.84, 26.56, 74.70, 31.80, 31.23, all P<0.05), and the concentrations of IL-1β, IL-6, and IL-8 in the cell supernatants decreased( F=197.80、1 339.00、1 308.00, all P<0.001). Conclusions:Rapid pacing of HL-1 cells can promote mtDNA release into the cytoplasm, activate the STING-IRF3 pathway, accelerate cellular senescence, and enhance the secretion of SASP.Inhibiting the expression of STING can delay the senescence induced by the rapid pacing of HL-1 cells and reduce SASP secretion.

To investigate the impact of high salt stress on the metabolic pathways and regulatory mecha-nisms involved in synthesizing hydroxyectoine(5-HE)in Virgibacillus salexigens,cultures were supple-mented with 1.5 and 2.5 mol/L NaCl as control and experimental groups,respectively.High-perform-ance liquid chromatography(HPLC)was used to detect the difference in the amount of 5-HE synthesis.Transcriptomic and metabolomic analyses identified differential genes and metabolites under varying salt concentrations.Key differential gene expressions related to 5-HE synthesis were validated using qRT-PCR.Results showed that 5-HE synthesis reached 121.9 mg/L at 2.5 mol/L NaCl.Transcriptomic anal-ysis identified 652 differentially expressed genes across 348 KEGG pathways,with 210 upregulated and 442 downregulated,primarily enriched in pathways such as purine metabolism,amino acid biosynthesis,sulfur metabolism,and biotin metabolism.Validation of 13 genes,including lysC,asd,ectA,ectB,ectC,ectD,thrB,thrC,ilvA,ilvE,AGXT,YckA and GlnQ,showed expression trends consistent with transcriptome data.Metabolomic analysis identified 1153 metabolites predominantly enriched in histidine metabolism,lysine degradation,and arginine and proline metabolism.This study preliminarily elucidated the effect of high salt on the 5-HE synthesis pathway,and provided a basis for the subsequent construc-tion of 5-HE high-yielding strains.

Objective:To investigate genetic findings and pregnancy outcomes in fetuses with omphalocele.Methods:This retrospective study analyzed data from 502 fetuses with prenatally diagnosed omphalocele who underwent genetic testing at Guangzhou Women and Children's Medical Center and Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region between January 2014 and March 2024. Testing methods included karyotyping, chromosomal microarray analysis (CMA), methylation-specific multiplex ligation-dependent probe amplification, and whole-exome sequencing (WES). Cases were categorized as non-isolated ( n=340) or isolated ( n=162) based on ultrasound findings. Differences in genetic abnormality detection rates and pregnancy outcomes were analyzed using Mann-Whitney U test, independent samples t-test, and Chi-square test (or Fisher's exact test). Results:Among 502 fetuses, karyotyping plus CMA detected chromosomal abnormalities in 223 cases (44.4%, 223/502), including trisomy 18 (57.0%, 127/223) and trisomy 13 (23.3%, 52/223). CMA additionally identified nine pathogenic copy number variations (1.8%, 9/502) and five uniparental disomies (1.0%, 5/502), increasing the total diagnostic yield from 44.4% to 47.2%. The genetic abnormality rate was significantly lower in isolated (14.8%, 24/162) versus non-isolated omphalocele (64.7%, 220/340) ( χ2=109.34, P<0.001). WES detected variants in nine of 16 karyotype/CMA-negative cases, including five pathogenic variants involving PIK3CA and CDKN1C. Eight imprinting disorders (1.6%, 8/502) were identified, including five Beckwith-Wiedemann syndrome cases. Among 499 cases with follow-up, 401 (80.4%, 401/499) underwent pregnancy termination. Live birth rate was higher in isolated versus non-isolated groups [42.5% (69/162) vs. 8.5% (29/340), χ2=77.67, P<0.001]. Three cases were lost to follow-up. The one-year survival rate was 93.9% (92/98) in live-born infants. Conclusion:Aneuploidy (particularly trisomy 18) is the primary genetic etiology of omphalocele. CMA and WES significantly improve diagnostic yield. Isolated omphalocele has a more favorable prognosis, while non-isolated cases show significantly higher genetic abnormality rates. A stratified testing strategy is recommended: karyotyping plus CMA for isolated cases and prioritization of WES for multiple anomalies.

Objective To design a training device of the flight crew for plateau normobaric low-oxygen acclimatization so as to enhance the flight crew's ability to adapt to the low oxygen environment after rushing into the plateau and reduce the incidence of acute plateau reaction.Methods The training device comprised a plateau environment simulation controller,a multimodal physiological acquisition system and hypoxia exercise training evaluation software.The plateau environment simulation controller was composed of an environment monitor for plateau acclimatization,two composite sensor sets,a control valve and an alarm device;the multimodal physiological acquisition system was made up of 20 groups of vital signs acquisi-tion devices,with a wearable dynamic ECG and respiration recorder,a wrist oximeter and an arm sphygmomano-meter included in each group.The hypoxia exercise training evaluation software was developed with a B/S architecture,Java language and JetBrains 2020.3.Results The training device proved to have the simulation altitude ranging from 0 to 6 000 m and facilitated simultaneous training of 20 persons for normobaric low-oxygen acclimatization,screening for hypoxia endurance,real-time monitoring of physiological parameters and assessment of training effect,with none of the trainees having acute plateau reaction.Conclusion The training device assists the flight crew for plateau normobaric low-oxygen acclimatization,and can be used for acclimatization training before plateau missions.[Chinese Medical Equipment Journal,2025,46(8):18-24]