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.

Background: Maturity-onset diabetes of the young (MODY) due to variants of hepatocyte nuclear factor 1-beta (HNF1β) (MODY5) has not been well studied in the Chinese population. This study aimed to estimate its prevalence and evaluate the application of a clinical screening method (Faguer score) in Chinese early-onset diabetes (EOD) patients. Methods: Among 679 EOD patients clinically diagnosed with type 2 diabetes mellitus (age at diagnosis ≤40 years), the exons of HNF1β were sequenced. Functional impact of rare variants was evaluated using a dual-luciferase reporter system. Faguer scores ≥8 prompted multiplex ligation-dependent probe amplification (MLPA) for large deletions. Pathogenicity of HNF1β variants was assessed following the American College of Medical Genetics and Genomics (ACMG) guidelines. Results: Two rare HNF1β missense mutations (E105K and G454R) were identified by sequencing in five patients, showing functional impact in vitro. Another patient was found to have a whole-gene deletion by MLPA in 22 patients with the Faguer score above 8. Following ACMG guidelines, six patients carrying pathogenic or likely pathogenic variant were diagnosed with MODY5. The estimated prevalence of MODY5 in Chinese EOD patients was approximately 0.9% or higher. Conclusion MODY5 is not uncommon in China. The Faguer score is helpful in deciding whether to perform MLPA analysis on patients with negative sequencing results.

Background: Maturity-onset diabetes of the young (MODY) due to variants of hepatocyte nuclear factor 1-beta (HNF1β) (MODY5) has not been well studied in the Chinese population. This study aimed to estimate its prevalence and evaluate the application of a clinical screening method (Faguer score) in Chinese early-onset diabetes (EOD) patients. Methods: Among 679 EOD patients clinically diagnosed with type 2 diabetes mellitus (age at diagnosis ≤40 years), the exons of HNF1β were sequenced. Functional impact of rare variants was evaluated using a dual-luciferase reporter system. Faguer scores ≥8 prompted multiplex ligation-dependent probe amplification (MLPA) for large deletions. Pathogenicity of HNF1β variants was assessed following the American College of Medical Genetics and Genomics (ACMG) guidelines. Results: Two rare HNF1β missense mutations (E105K and G454R) were identified by sequencing in five patients, showing functional impact in vitro. Another patient was found to have a whole-gene deletion by MLPA in 22 patients with the Faguer score above 8. Following ACMG guidelines, six patients carrying pathogenic or likely pathogenic variant were diagnosed with MODY5. The estimated prevalence of MODY5 in Chinese EOD patients was approximately 0.9% or higher. Conclusion MODY5 is not uncommon in China. The Faguer score is helpful in deciding whether to perform MLPA analysis on patients with negative sequencing results.

Background: Maturity-onset diabetes of the young (MODY) due to variants of hepatocyte nuclear factor 1-beta (HNF1β) (MODY5) has not been well studied in the Chinese population. This study aimed to estimate its prevalence and evaluate the application of a clinical screening method (Faguer score) in Chinese early-onset diabetes (EOD) patients. Methods: Among 679 EOD patients clinically diagnosed with type 2 diabetes mellitus (age at diagnosis ≤40 years), the exons of HNF1β were sequenced. Functional impact of rare variants was evaluated using a dual-luciferase reporter system. Faguer scores ≥8 prompted multiplex ligation-dependent probe amplification (MLPA) for large deletions. Pathogenicity of HNF1β variants was assessed following the American College of Medical Genetics and Genomics (ACMG) guidelines. Results: Two rare HNF1β missense mutations (E105K and G454R) were identified by sequencing in five patients, showing functional impact in vitro. Another patient was found to have a whole-gene deletion by MLPA in 22 patients with the Faguer score above 8. Following ACMG guidelines, six patients carrying pathogenic or likely pathogenic variant were diagnosed with MODY5. The estimated prevalence of MODY5 in Chinese EOD patients was approximately 0.9% or higher. Conclusion MODY5 is not uncommon in China. The Faguer score is helpful in deciding whether to perform MLPA analysis on patients with negative sequencing results.

Background: Maturity-onset diabetes of the young (MODY) due to variants of hepatocyte nuclear factor 1-beta (HNF1β) (MODY5) has not been well studied in the Chinese population. This study aimed to estimate its prevalence and evaluate the application of a clinical screening method (Faguer score) in Chinese early-onset diabetes (EOD) patients. Methods: Among 679 EOD patients clinically diagnosed with type 2 diabetes mellitus (age at diagnosis ≤40 years), the exons of HNF1β were sequenced. Functional impact of rare variants was evaluated using a dual-luciferase reporter system. Faguer scores ≥8 prompted multiplex ligation-dependent probe amplification (MLPA) for large deletions. Pathogenicity of HNF1β variants was assessed following the American College of Medical Genetics and Genomics (ACMG) guidelines. Results: Two rare HNF1β missense mutations (E105K and G454R) were identified by sequencing in five patients, showing functional impact in vitro. Another patient was found to have a whole-gene deletion by MLPA in 22 patients with the Faguer score above 8. Following ACMG guidelines, six patients carrying pathogenic or likely pathogenic variant were diagnosed with MODY5. The estimated prevalence of MODY5 in Chinese EOD patients was approximately 0.9% or higher. Conclusion MODY5 is not uncommon in China. The Faguer score is helpful in deciding whether to perform MLPA analysis on patients with negative sequencing results.

Objective To investigate the ameliorative effect of sulforaphane on inflammatory response and airway remodeling in rats with chronic obstructive pulmonary disease(COPD).Methods Seventy-five SD rats were randomly divided into the normal group,the model group,and the low-,medium-,and high-dose groups of sulforaphane,with 15 rats in each group.Except for the normal group,the COPD model was prepared in the remaining group using aroma smoke inhalation combined with intratracheal droplet lipopolysaccharide(LPS)method.After the successful modelling,the rats were administered the drug by gavage for 28 days.At the end of the administration,the general conditions of the rats in each group were observed,and the lung function[forced vital capacity(FVC),peak expiratory flow-rate(PEF),forceful expiratory volume in 1 second(FEV1)]was examined,and the pathological changes of the lung tissues were observed by hematoxylin-eosin(HE)staining method,and the indexes of airway remodeling(thickness of the bronchial wall,thickness of the smooth muscle)were measured;the enzyme-linked immunosorbent assay(ELISA)was used to examine the lung function of the rats.The levels of inflammatory factors[tumor necrosis factor α(TNF-α),interleukin 1β(IL-1β)]were detected in lung tissue by enzyme-linked immunosorbent assay(ELISA),and changes in the protein expressions of Toll-like receptor 4(TLR4),myeloid differentiation factor 88(MyD88),and nuclear transcription factor κB(NF-κB)were detected in lung tissue by Western Blot.Results(1)The rats in the model group had dry and lack of glossy fur,obvious coughing and nose scratching,shortness of breath,slow movement,and preferred to arch their backs and lie curled up;the rats in the low-,medium-and high-dose groups of sulforaphane showed significant improvement in shortness of breath,coughing,and other abnormal manifestations.(2)HE staining showed that the airway wall and smooth muscle of rats in the model group were thickened,the airway epithelium was damaged,and alveolar destruction,fusion,and massive infiltration of inflammatory cells were seen;the histopathological changes in the lungs of rats in the low-,medium-and high-dose groups of sulforaphane improved to varying degrees,with the airway wall becoming thinner,the degree of alveolar destruction being reduced,and the infiltration of inflammatory cells being reduced.(3)Compared with the normal group,FVC,PEF and FEV1 were significantly reduced in the model group(P＜0.05),and the levels of TNF-α and IL-1β,bronchial wall thickness,smooth muscle thickness,and the expression levels of TLR4,MyD88 and NF-κB were significantly increased in the model group(P＜0.05);and in comparison with the model group,the levels of FVC,PEF,and FEV1 were significantly increased in the rats in the sulforaphane low-,medium-,and high-dose groups(P＜0.05),and the levels of TNF-α,IL-1β,bronchial wall thickness,smooth muscle thickness,and the expression levels of TLR4,MyD88,and NF-κB were significantly decreased(P＜0.05)compared with the model group.Conclusion Sulforaphane helps to inhibit the inflammatory response,attenuate airway remodeling,and improve the pathological injury and lung function of lung tissue in rats with COPD,and its mechanism may be related to the inhibition of TLR4,MyD88,and NF-κB protein expressions.

Objective:To explore therapeutic effect of sacubitril valsartan sodium combined with Wenxin granule in the treatment of hypertension complicated with paroxysmal atrial fibrillation(AF)and its effect on cardiac electro-physiological structure.Methods:A total of 116 patients with hypertension and paroxysmal atrial fibrillation treated in our hospital from Oct 2021 to Nov 2022 were consecutively selected.According to random number table,they were divided into Wenxin granule group(received Wenxin granule treatment based on routine antihypertensive ther-apy)and combined treatment group(received sacubitril valsartan sodium combined Wenxin granule therapy based on routine antihypertensive therapy)with 58 cases in each group,and both groups were consecutively treated for six months.Clinical symptom score,AF burden,P wave duration,P wave dispersion,left atrial diameter(LAD),left ventricular end-diastolic diameter(LVEDd)and left ventricular ejection fraction(LVEF)were compared between two groups before and after treatment.Results:After treatment,compared with Wenxin granule group,there were significant reductions in clinical symptom score[(1.66±0.69)scores vs.(1.40±0.53)scores],AF burden[4.43(1.65)％vs.1.62(3.50)％],P wave duration[(112.17±6.46)ms vs.(109.29±8.59)ms],P wave dispersion[(32.47±8.11)ms vs.(29.02±7.49)ms]and LAD[(34.83±3.41)mm vs.(33.40±3.74)mm]in combined treatment group(P＜0.05 or＜0.01).There were no significant difference in LVEDd and LVEF between two groups,P＞0.05 both.Conclusion:Sacubitril valsartan sodium combined with Wenxin granule can significantly im-prove clinical symptoms and atrial fibrillation burden,reduce the susceptibility to atrial fibrillation,and inhibit atrial electrical remodeling and structural remodeling in patients with hypertension complicated with paroxysmal atrial fi-brillation.

Objective To understand the respiratory protection competency of staff in hospitals.Methods Staff from six hospitals of different levels and characteristics in Beijing were selected,including doctors,nurses,medical technicians,and servicers,to conduct knowledge assessment on respiratory protection competency.According to exposure risks of respiratory infectious diseases,based on actual cases and daily work scenarios,content of respira-tory protection competency assessment was designed from three aspects:identification of respiratory infectious di-seases,transmission routes and corresponding protection requirements,as well as correct selection and use of masks.The assessment included 6,6,and 8 knowledge points respectively,with 20 knowledge points in total,all of which were choice questions.For multiple-choice questions,full marks,partial marks,and no mark were given respective-ly if all options were correct,partial options were correct and without incorrect options,and partial options were correct but with incorrect options.Difficulty and discrimination analyses on question of each knowledge point was conducted based on classical test theory.Results The respiratory protection competency knowledge assessment for 326 staff members at different risk levels in 6 hospitals showed that concerning the 20 knowledge points,more than 60％participants got full marks for 6 points,while the proportion of full marks for other questions was relatively low.Less than 10％participants got full marks for the following 5 knowledge points:types of airborne diseases,types of droplet-borne diseases,conventional measures for the prevention and control of healthcare-associated infec-tion with respiratory infectious diseases,indications for wearing respirators,and indications for wearing medical protective masks.Among the 20 knowledge questions,5,1,and 14 questions were relatively easy,medium,and difficult,respectively;6,1,4,and 9 questions were with discrimination levels of ≥0.4,0.30-0.39,0.20-0.29,and ≤0.19,respectively.Conclusion There is still much room for hospital staff to improve their respiratory protection competency,especially in the recognition of diseases with different transmission routes and the indications for wearing different types of masks.

To characterize human antibodies against low-calcium response V(LcrV)antigen of Yersinia pestis,the mono-clonal antibodies were screened and assayed.Antibody gene was derived from peripheral blood mononuclear cells of the vaccin-ees immunized by plague subunit vaccine in phase Ⅱb clinical trial.Human ScFv antibody library was constructed by phage dis-play.After panning library by using recombinant LcrV antigen,antibody variable genes were sequenced and converted into IgG1 format to evaluate its binding specificity and relevant parameters.An anti-plague human ScFv antibody library was estab-lished contained 7.54× 108 independent clones.After panning by LcrV antigen,3 human antibodies named as RV-B4,RV-D1 and RV-E8,respectively,were identified.Using indirect enzyme-linked immunosorbent assay(ELISA)and Western blot(WB),the specific bindings of the mAbs to LcrV antigen were confirmed.The dissociation constant(KD)of them to LcrV is 2.1 nmol/L,1.24 nmol/L and 42 nmol/L,respectively.Minor protective efficacy was found among 3 human antibodies in Y.pestis 141-infected mice.Three anti-LcrV monoclonal antibodies generated from immunized vaccinees were binding specific antibod-ies and could not block plague infection in mice.These antibodies are the potential candidate reagents for basic research of plague immunity and the application of plague diagnosis.

ObjectiveThe detection of RNA single nucleotide polymorphism (SNP) is of great importance due to their association with protein expression related to various diseases and drug responses. At present, splintR ligase-assisted methods are important approaches for RNA direct detection, but its specificity will be limited when the fidelity of ligases is not ideal. The aim of this study was to create a method to improve the specificity of splintR ligase for RNA detection. MethodsIn this study, a dual-competitive-padlock-probe (DCPLP) assay without the need for additional enzymes or reactions is proposed to improve specificity of splintR ligase ligation. To verify the method, we employed dual competitive padlock probe-mediated rolling circle amplification (DCPLP-RCA) to genotype the CYP2C9 gene. ResultsThe specificity was well improved through the competition and strand displacement of dual padlock probe, with an 83.26% reduction in nonspecific signal. By detecting synthetic RNA samples, the method demonstrated a dynamic detection range of 10 pmol/L-1 nmol/L. Furthermore, clinical samples were applied to the method to evaluate its performance, and the genotyping results were consistent with those obtained using the qPCR method. ConclusionThis study has successfully established a highly specific direct RNA SNP detection method, and provided a novel avenue for accurate identification of various types of RNAs.