Objective:To obtain fucose-free anti-West Nile virus nonstructural protein 1 (NS1) antibody and evaluate its antibody-dependent cell-mediated cytotoxicity (ADCC).Methods:The guanosine diphosphate-fucose transporter SLC35C1 in CHO cells was knocked out using CRISPR/Cas9 gene editing technology to obtain the fucose-free cell line CHO SLC35C1 -/-. CHO SLC35C1 -/- cells were used to produce fucose-free anti-West Nile virus NS1 antibodies. The binding abilities of the antibodies to the target antigen of West Nile virus NS1 protein and the human high-affinity IgG Fc receptor hFcγRⅠ (hCD64) were detected by ELISA and flow cytometry, respectively. The ADCC activity of the antibodies was detected by ADCC reporter gene assay. One-way analysis of variance was used for statistical analysis. Results:CHO SLC35C1 -/- cells expressed green fluorescent protein but not Lens culinaris agglutinin. The anti-West Nile virus NS1 antibodies produced by CHO SLC35C1 -/- cells with a fucose content of 0.22% could bind to West Nile virus NS1 protein in a concentration-dependent manner. Compared with the wild-type antibodies, the fucose-free anti-West Nile virus NS1 antibodies showed a stronger binding ability to hFcγRⅠ(hCD64), as indicated by a significant increase in fluorescence intensity. The ADCC reporter gene assay showed that the fucose-free anti-West Nile virus NS1 antibodies had increased activity as compared with the wild-type antibodies ( P<0.001). Conclusion:The fucose-free anti-West Nile virus NS1 antibodies may be used to protect against West Nile virus infection.

Objective To evaluate the reliability of Vitek 2 AST-N335 card for determining the susceptibility of Acinetobacter bauman-nii(AB)to cefoperazone/sulbactam.Methods A total of 318 non-repeated clinical isolates of AB collected in 2023 were tested for antimicrobial susceptibility to cefoperazone/sulbactam using broth microdilution(BMD),the AST-N335 card,and the Kirby-Bauer(K-B)disk diffusion method.Using BMD as the reference method,the reliability of AST-N335 card was assessed,and the accuracy of K-B disk diffusion method as the confirmatory test was validated.Results Compared with BMD,the susceptibility testing of 318 AB strains to cefoperazone/sulbactam using the AST-N335 card showed categorical agreement(CA)of 87.8％(279/318),very major er-ror(VME)of 6.0％(19/318),major error(ME)of 0％(0/318),and minor error(mE)of 1.9％(6/318),which fall outside of the acceptable error range.In contrast,the K-B method achieved CA of 99.4％(316/318),VME of 0％,ME of 0.3％(1/318),and mE of 0.3％(1/318),all within acceptable limits.Of these,the errors with AST-N335 card occurred within the minimum inhibitory concentration(MIC)range of 8-32 μg/mL.Using BMD as the reference method,further analysis was performed on the 171 AB strains with AST-N335 card MIC values of 8-32 μg/mL for cefoperazone/sulbactam.It was revealed that at MIC of 32 μg/mL,the CA was 0％;at MIC of 16 μg/mL,CA was 5.3％(1/19)and VME rate was 84.2％(16/19),both of which substantially exceeded accepta-ble error ranges.At MIC of 8 μg/mL,the CA was 94.9％(131/138)and VME was 2.2％(3/138),both approaching the acceptable ranges.Conclusion The results obtained with Vitek 2 AST-N335 card in determining for cefoperazone/sulbactam are unreliable when the MIC values fall within the range of 8-32 μg/mL,which leads to an underestimation of the resistance rate to cefoperazone/sulbac-tam.This issue requires urgent attention in both laboratories and clinical practice.The K-B disk diffusion method could serve as a sup-plementary verification approach in routine laboratories.

Objective:To evaluate the association between body mass index (BMI) and bone mineral density of calcaneus in adults.Methods:Data of the second resurvey of China Kadoorie Biobank study from Tongxiang of Zhejiang Province were used. A total of 2 896 participants aged 44-84 years were included in the final analysis. Overweight was defined as 23.0 kg/m 2≤BMI<25.0 kg/m 2, and obesity was defined as BMI ≥25.0 kg/m 2 based on the criteria recommended by WHO/West Pacific Region. Multiple linear regression model was used to evaluate the association between BMI and calcaneus bone mineral density. Restricted cubic splines were used to investigate the dose-response relationship between BMI and calcaneus bone mineral density. Results:The calcaneus bone mineral density in the study subjects were as follow ( x± SE): the broadband ultrasound attenuation was (109.4±12.1) dB/MHz, the speed of ultrasound was (1 545.9±33.8) m/s, and the stiffness index was 85.7±15.8. After adjusting for socio-demographic factors, lifestyle, waist circumference, diabetes and hypertension prevalence, BMI was positively associated with calcaneus stiffness index in non-overweight and non-obese adults, with β of 2.30 (95% CI: 1.11-3.49) for men ( P<0.001) and 1.08 (95% CI: 0.38-1.78) for women ( P=0.003), respectively. In addition, BMI was positively associated with calcaneus stiffness index in overweight and obese women ( β=0.90, 95% CI: 0.38-1.42) ( P<0.001), and null association was found in overweight and obese men ( β=0.06, 95% CI: -0.92-1.04) ( P=0.900). Restricted cubic spline model showed a nonlinear dose-response relationship between BMI and calcaneus stiffness index. Conclusion:Non-linear association was found between BMI with calcaneus bone mineral density in adults.

Objective:To revise and enlarge the specification of pharmaceutical excipient sucrose palmitate.Methods:Reference to JP2018,USP-NF 2023,EP1 1.0,Chinese Pharmacopoeia 2020 edition of the four general rules and the first supplement of sucrose stearate pharmacopoeia standards and other relevant requirements for standard research.Results:According to the quality of the product and the actual application in the formulation,the quality standards for the pharmaceutical excipient sucrose palmitate will be studied.At present,the quality standard of sucrose palmitate for pharmaceutical excipients has been disclosed.Conclusion:The established stand-ard will provide the quality guarantee for the application of sucrose palmitate in medicines.

Objective:To revise and enlarge the specification of pharmaceutical excipient sucrose palmitate.Methods:Reference to JP2018,USP-NF 2023,EP1 1.0,Chinese Pharmacopoeia 2020 edition of the four general rules and the first supplement of sucrose stearate pharmacopoeia standards and other relevant requirements for standard research.Results:According to the quality of the product and the actual application in the formulation,the quality standards for the pharmaceutical excipient sucrose palmitate will be studied.At present,the quality standard of sucrose palmitate for pharmaceutical excipients has been disclosed.Conclusion:The established stand-ard will provide the quality guarantee for the application of sucrose palmitate in medicines.

Objective:To obtain fucose-free anti-West Nile virus nonstructural protein 1 (NS1) antibody and evaluate its antibody-dependent cell-mediated cytotoxicity (ADCC).Methods:The guanosine diphosphate-fucose transporter SLC35C1 in CHO cells was knocked out using CRISPR/Cas9 gene editing technology to obtain the fucose-free cell line CHO SLC35C1 -/-. CHO SLC35C1 -/- cells were used to produce fucose-free anti-West Nile virus NS1 antibodies. The binding abilities of the antibodies to the target antigen of West Nile virus NS1 protein and the human high-affinity IgG Fc receptor hFcγRⅠ (hCD64) were detected by ELISA and flow cytometry, respectively. The ADCC activity of the antibodies was detected by ADCC reporter gene assay. One-way analysis of variance was used for statistical analysis. Results:CHO SLC35C1 -/- cells expressed green fluorescent protein but not Lens culinaris agglutinin. The anti-West Nile virus NS1 antibodies produced by CHO SLC35C1 -/- cells with a fucose content of 0.22% could bind to West Nile virus NS1 protein in a concentration-dependent manner. Compared with the wild-type antibodies, the fucose-free anti-West Nile virus NS1 antibodies showed a stronger binding ability to hFcγRⅠ(hCD64), as indicated by a significant increase in fluorescence intensity. The ADCC reporter gene assay showed that the fucose-free anti-West Nile virus NS1 antibodies had increased activity as compared with the wild-type antibodies ( P<0.001). Conclusion:The fucose-free anti-West Nile virus NS1 antibodies may be used to protect against West Nile virus infection.

Objective:To obtain a polyvalent single-chain variable fragment（scFv）against West Nile virus through PEGylation in order to improve its antigen-binding ability and neutralizing activity.Methods:A scFv carrying a C-terminal cysteine residue（scFvC）was constructed by introducing Cys into the C-terminal of scFv against West Nile virus. Then the multimerization of scFvC was achieved by targeting the thiol group of Cys with maleimide-activated polyethylene glycol. ELISA was used to detect the antigen-binding activity of the multivalent scFvC. Pseudovirus-based neutralization assay was used to evaluate the neutralizing activity of the multivalent scFvC in vitro. One-way analysis of variance was used for statistical analysis. Results:The PEGylated scFvC multimers showed higher antigen-binding ability than the monomeric scFvC. In the pseudovirus-based neutralization assay，both monomeric scFvC and PEGylated scFvC multimers showed good neutralizing activity compared with the control group（ P<0.000 1）. Moreover，the PEGylated scFvC multimers showed a more effective ability to block the pseudovirus infection in target cells（ P<0.05），suggesting that the PEGylated scFvC multimers could enhance their function in vitro through avidity effect. Conclusion:In this study，a scFvC targeting West Nile virus is successfully constructed and its polyvalent form is generated through PEGylation，which improves the antigen-binding and neutralizing activity of the parental scFv.

Objective:To evaluate the association between body mass index (BMI) and bone mineral density of calcaneus in adults.Methods:Data of the second resurvey of China Kadoorie Biobank study from Tongxiang of Zhejiang Province were used. A total of 2 896 participants aged 44-84 years were included in the final analysis. Overweight was defined as 23.0 kg/m 2≤BMI<25.0 kg/m 2, and obesity was defined as BMI ≥25.0 kg/m 2 based on the criteria recommended by WHO/West Pacific Region. Multiple linear regression model was used to evaluate the association between BMI and calcaneus bone mineral density. Restricted cubic splines were used to investigate the dose-response relationship between BMI and calcaneus bone mineral density. Results:The calcaneus bone mineral density in the study subjects were as follow ( x± SE): the broadband ultrasound attenuation was (109.4±12.1) dB/MHz, the speed of ultrasound was (1 545.9±33.8) m/s, and the stiffness index was 85.7±15.8. After adjusting for socio-demographic factors, lifestyle, waist circumference, diabetes and hypertension prevalence, BMI was positively associated with calcaneus stiffness index in non-overweight and non-obese adults, with β of 2.30 (95% CI: 1.11-3.49) for men ( P<0.001) and 1.08 (95% CI: 0.38-1.78) for women ( P=0.003), respectively. In addition, BMI was positively associated with calcaneus stiffness index in overweight and obese women ( β=0.90, 95% CI: 0.38-1.42) ( P<0.001), and null association was found in overweight and obese men ( β=0.06, 95% CI: -0.92-1.04) ( P=0.900). Restricted cubic spline model showed a nonlinear dose-response relationship between BMI and calcaneus stiffness index. Conclusion:Non-linear association was found between BMI with calcaneus bone mineral density in adults.

Objective To evaluate the reliability of Vitek 2 AST-N335 card for determining the susceptibility of Acinetobacter bauman-nii(AB)to cefoperazone/sulbactam.Methods A total of 318 non-repeated clinical isolates of AB collected in 2023 were tested for antimicrobial susceptibility to cefoperazone/sulbactam using broth microdilution(BMD),the AST-N335 card,and the Kirby-Bauer(K-B)disk diffusion method.Using BMD as the reference method,the reliability of AST-N335 card was assessed,and the accuracy of K-B disk diffusion method as the confirmatory test was validated.Results Compared with BMD,the susceptibility testing of 318 AB strains to cefoperazone/sulbactam using the AST-N335 card showed categorical agreement(CA)of 87.8％(279/318),very major er-ror(VME)of 6.0％(19/318),major error(ME)of 0％(0/318),and minor error(mE)of 1.9％(6/318),which fall outside of the acceptable error range.In contrast,the K-B method achieved CA of 99.4％(316/318),VME of 0％,ME of 0.3％(1/318),and mE of 0.3％(1/318),all within acceptable limits.Of these,the errors with AST-N335 card occurred within the minimum inhibitory concentration(MIC)range of 8-32 μg/mL.Using BMD as the reference method,further analysis was performed on the 171 AB strains with AST-N335 card MIC values of 8-32 μg/mL for cefoperazone/sulbactam.It was revealed that at MIC of 32 μg/mL,the CA was 0％;at MIC of 16 μg/mL,CA was 5.3％(1/19)and VME rate was 84.2％(16/19),both of which substantially exceeded accepta-ble error ranges.At MIC of 8 μg/mL,the CA was 94.9％(131/138)and VME was 2.2％(3/138),both approaching the acceptable ranges.Conclusion The results obtained with Vitek 2 AST-N335 card in determining for cefoperazone/sulbactam are unreliable when the MIC values fall within the range of 8-32 μg/mL,which leads to an underestimation of the resistance rate to cefoperazone/sulbac-tam.This issue requires urgent attention in both laboratories and clinical practice.The K-B disk diffusion method could serve as a sup-plementary verification approach in routine laboratories.

Objective:To obtain a polyvalent single-chain variable fragment（scFv）against West Nile virus through PEGylation in order to improve its antigen-binding ability and neutralizing activity.Methods:A scFv carrying a C-terminal cysteine residue（scFvC）was constructed by introducing Cys into the C-terminal of scFv against West Nile virus. Then the multimerization of scFvC was achieved by targeting the thiol group of Cys with maleimide-activated polyethylene glycol. ELISA was used to detect the antigen-binding activity of the multivalent scFvC. Pseudovirus-based neutralization assay was used to evaluate the neutralizing activity of the multivalent scFvC in vitro. One-way analysis of variance was used for statistical analysis. Results:The PEGylated scFvC multimers showed higher antigen-binding ability than the monomeric scFvC. In the pseudovirus-based neutralization assay，both monomeric scFvC and PEGylated scFvC multimers showed good neutralizing activity compared with the control group（ P<0.000 1）. Moreover，the PEGylated scFvC multimers showed a more effective ability to block the pseudovirus infection in target cells（ P<0.05），suggesting that the PEGylated scFvC multimers could enhance their function in vitro through avidity effect. Conclusion:In this study，a scFvC targeting West Nile virus is successfully constructed and its polyvalent form is generated through PEGylation，which improves the antigen-binding and neutralizing activity of the parental scFv.