A N-acetylneuraminate lyase gene (shnal) from Staphylococcus hominis was cloned into pET-28a and expressed in Escherichia coli BL21 (DE3) host cells. The recombinant enzyme was purified and characterized. It is a homotetrameric enzyme with the optimum pH at 8.0 for the cleavage direction and the optimum pH and temperature were 7.5 and 45 degrees C for the synthetic direction. The activity of ShNAL is stable when incubated at 45 degrees C for 2 h but decreased rapidly over 50 degrees C. ShNAL showed high stability in a wide range pH from 5.0 to 10.0 with the residual activity being > 70% when the enzyme was incubated in different buffers at 4 degrees C for 24 h. Its K(m) towards N-acetylneuraminic acid, pyruvate and ManNAc were (4.0 +/- 0.2) mmol/L, (35.1 +/- 3.2) mmol/L and (131.7 +/- 12.1) mmol/L, respectively. The k(cat)/K(m) value of Neu5Ac, ManNAc, and Pyr for ShNAL were 1.9 L/(mmol x s), 0.08 L/(mmol x s) and 0.08 L/(mmol x s), respectively.
Bacterial Proteins ; genetics ; metabolism ; Cloning, Molecular ; Enzyme Stability ; Escherichia coli ; genetics ; metabolism ; Hydrogen-Ion Concentration ; Oxo-Acid-Lyases ; genetics ; metabolism ; Recombinant Proteins ; genetics ; metabolism ; Staphylococcus hominis ; enzymology ; Temperature

Objective:To explore the health economic evaluation methods of disease screening,providing insights for scholars conducting related research.Methods:By integrating relevant content from modem epidemiology,health statistics,and health economics,it investigates the differences in conducting health economic evaluations of disease screening using authenticity indicators(sensitivity,specificity)and predictive value indicators(positive predictive value,negative predictive value),and combines empirical studies with cases from the literature.Results:Authenticity indicators(sensitivity,specificity)are intrinsic measures of diagnostic tests,unaffected by the disease prevalence in the sample population,making them more suitable for conducting health economic evaluations of disease screening.Moreover,authenticity indicators are easy to obtain,and the model calculations are straightforward and convenient.Case study results demonstrate that compared to risk score screening,the Incremental Cost-Effectiveness Ratio(ICER)of fasting plasma glucose(FPG)testing for type 2 diabetes is 626,indicating that for every additional diabetic patient identified through risk score screening,an extra 626 yuan is spent.Conclusion:It is recommended to use authenticity indicators for conducting health economic evaluations of disease screening,standardize the path methods for model selection,and continuously improve the evidence quality of health economic evaluations of disease screening in China.

Objective:To explore the health economic evaluation methods of disease screening,providing insights for scholars conducting related research.Methods:By integrating relevant content from modem epidemiology,health statistics,and health economics,it investigates the differences in conducting health economic evaluations of disease screening using authenticity indicators(sensitivity,specificity)and predictive value indicators(positive predictive value,negative predictive value),and combines empirical studies with cases from the literature.Results:Authenticity indicators(sensitivity,specificity)are intrinsic measures of diagnostic tests,unaffected by the disease prevalence in the sample population,making them more suitable for conducting health economic evaluations of disease screening.Moreover,authenticity indicators are easy to obtain,and the model calculations are straightforward and convenient.Case study results demonstrate that compared to risk score screening,the Incremental Cost-Effectiveness Ratio(ICER)of fasting plasma glucose(FPG)testing for type 2 diabetes is 626,indicating that for every additional diabetic patient identified through risk score screening,an extra 626 yuan is spent.Conclusion:It is recommended to use authenticity indicators for conducting health economic evaluations of disease screening,standardize the path methods for model selection,and continuously improve the evidence quality of health economic evaluations of disease screening in China.

Objective:To explore the health economic evaluation methods of disease screening,providing insights for scholars conducting related research.Methods:By integrating relevant content from modem epidemiology,health statistics,and health economics,it investigates the differences in conducting health economic evaluations of disease screening using authenticity indicators(sensitivity,specificity)and predictive value indicators(positive predictive value,negative predictive value),and combines empirical studies with cases from the literature.Results:Authenticity indicators(sensitivity,specificity)are intrinsic measures of diagnostic tests,unaffected by the disease prevalence in the sample population,making them more suitable for conducting health economic evaluations of disease screening.Moreover,authenticity indicators are easy to obtain,and the model calculations are straightforward and convenient.Case study results demonstrate that compared to risk score screening,the Incremental Cost-Effectiveness Ratio(ICER)of fasting plasma glucose(FPG)testing for type 2 diabetes is 626,indicating that for every additional diabetic patient identified through risk score screening,an extra 626 yuan is spent.Conclusion:It is recommended to use authenticity indicators for conducting health economic evaluations of disease screening,standardize the path methods for model selection,and continuously improve the evidence quality of health economic evaluations of disease screening in China.

Objective:To explore the health economic evaluation methods of disease screening,providing insights for scholars conducting related research.Methods:By integrating relevant content from modem epidemiology,health statistics,and health economics,it investigates the differences in conducting health economic evaluations of disease screening using authenticity indicators(sensitivity,specificity)and predictive value indicators(positive predictive value,negative predictive value),and combines empirical studies with cases from the literature.Results:Authenticity indicators(sensitivity,specificity)are intrinsic measures of diagnostic tests,unaffected by the disease prevalence in the sample population,making them more suitable for conducting health economic evaluations of disease screening.Moreover,authenticity indicators are easy to obtain,and the model calculations are straightforward and convenient.Case study results demonstrate that compared to risk score screening,the Incremental Cost-Effectiveness Ratio(ICER)of fasting plasma glucose(FPG)testing for type 2 diabetes is 626,indicating that for every additional diabetic patient identified through risk score screening,an extra 626 yuan is spent.Conclusion:It is recommended to use authenticity indicators for conducting health economic evaluations of disease screening,standardize the path methods for model selection,and continuously improve the evidence quality of health economic evaluations of disease screening in China.

Objective:To explore the health economic evaluation methods of disease screening,providing insights for scholars conducting related research.Methods:By integrating relevant content from modem epidemiology,health statistics,and health economics,it investigates the differences in conducting health economic evaluations of disease screening using authenticity indicators(sensitivity,specificity)and predictive value indicators(positive predictive value,negative predictive value),and combines empirical studies with cases from the literature.Results:Authenticity indicators(sensitivity,specificity)are intrinsic measures of diagnostic tests,unaffected by the disease prevalence in the sample population,making them more suitable for conducting health economic evaluations of disease screening.Moreover,authenticity indicators are easy to obtain,and the model calculations are straightforward and convenient.Case study results demonstrate that compared to risk score screening,the Incremental Cost-Effectiveness Ratio(ICER)of fasting plasma glucose(FPG)testing for type 2 diabetes is 626,indicating that for every additional diabetic patient identified through risk score screening,an extra 626 yuan is spent.Conclusion:It is recommended to use authenticity indicators for conducting health economic evaluations of disease screening,standardize the path methods for model selection,and continuously improve the evidence quality of health economic evaluations of disease screening in China.

Objective:To explore the health economic evaluation methods of disease screening,providing insights for scholars conducting related research.Methods:By integrating relevant content from modem epidemiology,health statistics,and health economics,it investigates the differences in conducting health economic evaluations of disease screening using authenticity indicators(sensitivity,specificity)and predictive value indicators(positive predictive value,negative predictive value),and combines empirical studies with cases from the literature.Results:Authenticity indicators(sensitivity,specificity)are intrinsic measures of diagnostic tests,unaffected by the disease prevalence in the sample population,making them more suitable for conducting health economic evaluations of disease screening.Moreover,authenticity indicators are easy to obtain,and the model calculations are straightforward and convenient.Case study results demonstrate that compared to risk score screening,the Incremental Cost-Effectiveness Ratio(ICER)of fasting plasma glucose(FPG)testing for type 2 diabetes is 626,indicating that for every additional diabetic patient identified through risk score screening,an extra 626 yuan is spent.Conclusion:It is recommended to use authenticity indicators for conducting health economic evaluations of disease screening,standardize the path methods for model selection,and continuously improve the evidence quality of health economic evaluations of disease screening in China.

Objective:To explore the health economic evaluation methods of disease screening,providing insights for scholars conducting related research.Methods:By integrating relevant content from modem epidemiology,health statistics,and health economics,it investigates the differences in conducting health economic evaluations of disease screening using authenticity indicators(sensitivity,specificity)and predictive value indicators(positive predictive value,negative predictive value),and combines empirical studies with cases from the literature.Results:Authenticity indicators(sensitivity,specificity)are intrinsic measures of diagnostic tests,unaffected by the disease prevalence in the sample population,making them more suitable for conducting health economic evaluations of disease screening.Moreover,authenticity indicators are easy to obtain,and the model calculations are straightforward and convenient.Case study results demonstrate that compared to risk score screening,the Incremental Cost-Effectiveness Ratio(ICER)of fasting plasma glucose(FPG)testing for type 2 diabetes is 626,indicating that for every additional diabetic patient identified through risk score screening,an extra 626 yuan is spent.Conclusion:It is recommended to use authenticity indicators for conducting health economic evaluations of disease screening,standardize the path methods for model selection,and continuously improve the evidence quality of health economic evaluations of disease screening in China.

Objective:To explore the health economic evaluation methods of disease screening,providing insights for scholars conducting related research.Methods:By integrating relevant content from modem epidemiology,health statistics,and health economics,it investigates the differences in conducting health economic evaluations of disease screening using authenticity indicators(sensitivity,specificity)and predictive value indicators(positive predictive value,negative predictive value),and combines empirical studies with cases from the literature.Results:Authenticity indicators(sensitivity,specificity)are intrinsic measures of diagnostic tests,unaffected by the disease prevalence in the sample population,making them more suitable for conducting health economic evaluations of disease screening.Moreover,authenticity indicators are easy to obtain,and the model calculations are straightforward and convenient.Case study results demonstrate that compared to risk score screening,the Incremental Cost-Effectiveness Ratio(ICER)of fasting plasma glucose(FPG)testing for type 2 diabetes is 626,indicating that for every additional diabetic patient identified through risk score screening,an extra 626 yuan is spent.Conclusion:It is recommended to use authenticity indicators for conducting health economic evaluations of disease screening,standardize the path methods for model selection,and continuously improve the evidence quality of health economic evaluations of disease screening in China.