In this study, we constructed a series of recombinant Fc variants of immunoglobulin G4 (IgG4), screened the fragment crystallizable (Fc) variants with significantly prolonged serum half-lives, and analyzed the relationship between mutation site and half-life, aiming to provide a theoretical basis for the development of IgG4 antibodies and Fc fusion protein-based drugs. Nine gene sites were selected for mutation, and different mutation sites were combined. The variant expression plasmids pET24b-Fc were constructed by molecular cloning and point mutation. The plasmids were transformed into Escherichia coli BL21(DE3) for the expression of different recombinant proteins of Fc. Fc2 and Fc3 variants had slightly lower recombinant protein yields, and the expression of other variants was not affected. The toxicity of different Fc variants was determined by cell counting kit-8 (CCK-8) and calcein acetoxymethyl ester/ propidium iodide (calcein AM/PI) in vitro and enzyme-linked immuno sorbent assay (ELISA) in vivo. The results showed that the recombinant Fc variants had good biocompatibility and safety. Finally, the Fc variants were labeled with fluorescent markers, and the effects of different mutations on their serum half-lives were investigated by in vivo experiments. The Fc5 variant with prolonged serum half-life was successfully screened out, which provided a theoretical and practical basis for the optimal design of IgG4 subtype antibody and Fc fusion protein drugs.
Immunoglobulin G/blood* ; Immunoglobulin Fc Fragments/biosynthesis* ; Half-Life ; Animals ; Escherichia coli/metabolism* ; Humans ; Recombinant Fusion Proteins/biosynthesis* ; Recombinant Proteins/biosynthesis* ; Mice

Triple-negative breast cancer (TNBC) is a highly aggressive malignancy predominantly managed via chemotherapy. Our clinical sample analysis revealed a significant correlation between elevated CD24 expression in TNBC tumor cells and patient survival rates. We developed a novel antibody-drug conjugate (ADC), named HN03, consisting of an antibody with engineered cysteines for site-specific conjugation with a low toxic nitric oxide (NO) precursor as its payload through a novel Pt(IV)-mediated bioorthogonal self-cleavable linker. HN03 specifically targets tumor cells expressing high levels of CD24, concurrently generating cisplatin and releasing NO upon activation. HN03 also exhibited potent in vitro and in vivo antitumor activity. It significantly reduced tumor growth at various doses, prevented tumor metastasis, with markedly lower toxicity than traditional chemotherapy agents. We found that a key mechanism of its action involved inducing apoptosis and endoplasmic reticulum stress, substantially decreasing the number of M2-type macrophages. Overall, HN03 stands out as a promising therapeutic option for TNBC, offering a targeted treatment with reduced side effects and the potential for improved outcomes. Furthermore, using Pt(IV) in the linker and an NO precursor as the payload enhances the versatility of the Antibody-NO donor Conjugate (ANC), offering new avenues for the design of the next generation of ADCs.

Objective: To establish a method for determining the molecular weight and molecular weight distribution of Poly(Lactide-co-Glycolide Acid) (PLGA) using Size Exclusion Chromatography-Refractive Index-Multiangle Laser Light Scattering (SEC-RI-MALLS) and Size Exclusion Chromatography-Refractive Index (SEC-RID), and to compare the results obtained from these two methods.
Methods: For SEC-RI-MALLS, tetrahydrofuran was used as the mobile phase, Shodex GPC KF-803L was employed as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, and an injection volume of 100 μL. For SEC-RID, tetrahydrofuran was also used as the mobile phase, Agilent PLgel 5 μm MIXD-D was used as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, differential detector temperature at 35 ℃, and an injection volume of 20 μL. The molecular weight and molecular weight distribution were calculated using Agilent’s GPC software. The newly established methods were validated methodologically, and the molecular weight and molecular weight distribution of 13 batches of samples were determined.
Results: The precision, accuracy, stability, and repeatability tests for SEC-RI-MALLS showed RSD values of 1.35%, 1.58%, 1.53%, and 1.26%, respectively. The SEC-RID method exhibited good linearity (r=0.999 9), with RSD values for precision, accuracy, stability, and repeatability tests (n=6) of 2.05%, 1.62%, 1.30%, and 2.97%, respectively. The results obtained from SEC-RI-MALLS were lower than those from SEC-RID, and the molecular weight distribution coefficient was smaller, but the results from the paired T-test performed with the value measured by SEC-RID method and the value measured by SEC-RI-MALLS method multiplied a conversion coefficient of 1.5 showed no significant difference between the two methods.
Conclusion: Both methods are stable and reliable, and can be used for the determination of PLGA molecular weight and molecular weight distribution based on the specific situations.

Poly(lactic-co-glycolide)(PLGA)is a key excipient in long-acting sustained-release preparations,and its degradation properties directly affect the drug release behavior.In this study,PLGA microspheres were prepared by microfluidic techniques,and the morphology changes of the microspheres were observed by scanning electron microscopy(SEM).In alkaline environment,due to the accelerated hydrolysis of ester bonds,the surface of the microspheres was rapidly dissolved and eroded,and the degradation rate was significantly higher than that in acidic environment.High temperature accelerated the degradation of PLGA microspheres.Under neutral and alkaline conditions,the microspheres showed aggregation and adhesion.Under acidic conditions,the microspheres gradually decomposed into irregular fragments.The high ionic strength further promoted the surface corrosion of the microspheres,especially under extreme pH conditions.Simultaneously,PLGA microspheres encapsulating coumarin were prepared to simulate the microsphere formulation.The release rate of coumarin after degradation of the microspheres under different conditions was observed by measuring the absorbance with ultraviolet-visible spectrophotometry.The results were consistent with those of the blank microspheres.This study revealed that the degradation of PLGA microspheres was significantly pH-dependent,temperature sensitive and ion strength responsive.These findings not only helped to understand and optimize the long-term stability and controlled release performance of drug-carrying microspheres,but also provided a theoretical basis for further improvement of PLGA-based drug carrier design.

Objective:To revise the quality standards of pharmaceutical excipients egg yolk lecithin and egg yolk lecithin(for injection)in Chinese Pharmacopoeia of 2025.Methods:Study on the quality of egg yolk lecithin by research on the crucial quality attributes and comparing domestic and abroad quality standards in pharmacopoeias.Results:Identification,water,residual solvents,and assay have been revised and free fatty acids has been deleted in the quality standard for egg yolk lecithin.Identification,water,residual solvents,related substances,bacterial endotoxins,and assay have been revised and free fatty acids has been deleted in the quality standard for egg yolk lecithin(for injection).Conclusion:The revised quality standards for egg yolk lecithin and egg yolk lecithin(for injection)have been included in the Chinese Pharmacopoeia of 2025,which provide data support and basis for qual-ity control and scientific supervision of egg yolk lecithin.

Objective To understand the current situation of healthcare-associated infection(HAI)in China,pro-vide data support and decision-making basis for formulating scientific and effective strategies for HAI prevention and control.Methods A nationwide cross-sectional survey on HAI was conducted among various types and levels of medical institutions in China according to a unified protocol of bedside surveys and case investigations.Results In 2024,a total of 5 736 medical institutions and 2 751 765 patients were surveyed.Among them,34 889 HAI cases were identified,with a prevalence rate of 1.27％.The number of HAI episodes was 38 032,and case prevalence rate was 1.38％.The prevalence rate of HAI in medical institutions in different regions of China ranged from 0.66％to 2.35％.Among medical institutions of different scales,those with a bed capacity of ≥900 had the high-est incidence of HAI,reaching 1.65％.The most common infection site was the lower respiratory tract(44.66％),followed by the urinary tract(12.94％),surgical site(9.32％),upper respiratory tract(7.02％),and bloodstream infection(5.78％).The top 3 departments with the highest HAI rates were the general intensive care unit(10.02％),department of neurosurgery(5.51％),and department(group)of hematology(5.34％).A total of 23 238 strains of HAI pathogens were detected,with 10 714 strains(46.10％)from lower respiratory tract speci-mens.The top 5 detected strains were Klebsiella pneumoniae(14.76％),Pseudomonas aeruginosa(13.33％),Escherichia coli(12.79％),Acinetobacter baumannii(9.23％),and Staphylococcus aureus(7.88％).231 944 pa-tients underwent class Ⅰ incision surgery were monitored,with 1 647 cases experienced surgical site infection,and the prevalence rate of surgical site infection was 0.71％.The number of patients who should undergo pathogen de-tection(patients receiving therapeutic and therapeutic combined prophylactic antimicrobial agents)was 715 179,while the actual number was 480 492,with a pathogen detection rate of 67.18％.425 225 patients received patho-genic detection before treatment,with a detection rate of 59.46％.Conclusion The overall HAI prevalence in Chi-na is lower,showing disparities among medical institutions of different regions and scales.Therefore,precise imple-mentation of measures is necessary for HAI prevention and control,with a focus on high-risk institutions and high-risk departments,key areas,and critical procedures.All levels of medical institutions should continuously reduce the incidence of HAI by strengthening monitoring,standardizing the use of antimicrobial agents,and reinforcing basic HAI prevention and control measures.

Objective To explore the relationship between serum chitosinase 3-like protein 1(CHI3L1)and Syndecan-1(SDC1)levels and bone metabolism in elderly patients with type 2 diabetes mellitus and their predictive efficacy on osteoporosis.Methods A total of 412 elderly patients with type 2 diabetes admitted to this hospital from May 2019 to May 2023 were included in this study,and were divided into normal bone mass group(n=151),reduced bone mass group(n=138)and osteoporosis group(n=123)according to the iffer-ences in bone mineral density.Serum CHI3L1 and SDC1 levels were detected by enzyme-linked immunosor-bent assay,and serum levels of type 1 collagen cross-linked carboxyl terminal peptide(CTX),25-hydroxyvita-min D[25-(OH)D],osteocalcin(OC),and type 1 procollagen N-terminal propeptide(P1NP)were deter-mined by automatic chemiluminescence immunoassay.Pearson correlation analysis was used to investigate the relationship between serum CHI3L1,SDC1 and bone metabolism in elderly patients with type 2 diabetes.Re-ceiver operating characteristic(ROC)curve was drawn to evaluate the predictive value of serum CHI3L1 and SDC1 on osteoporosis in elderly patients with type 2 diabetes.Multivariate Logistic regression analysis was used to investigate the influencing factors of osteoporosis in elderly patients with type 2 diabetes.Results There were significant differences in diabetes course,fasting blood glucose,HbA1c and HDL-C a-mong normal bone mass group,decreased bone mass group and osteoporosis group(P＜0.05).The levels of serum CHI3L1,25-(OH)D,P1NP and osteocalcin in osteoporosis group were lower than those in osteopenia group,and those in osteopenia group were lower than those in normal bone mass group,the differences were statistically significant(P＜0.05).Serum SDC1 and CTX levels in osteoporosis group were higher than those in osteopenia group,and those in osteopenia group were higher than those in normal bone mass group,the differences were statistically significant(P＜0.05).Serum CHI3L1 was positively correlated with 25-(OH)D,P1NP and OC(P＜0.05),and negatively correlated with CTX(P＜0.05).Serum SDC1 was negatively correlated with 25-(OH)D,P1NP,OC(P＜0.05),and positively correlated with CTX(P＜0.05).The area under the curve(AUC)of serum CHI3L1,SDC1 and their combination predicted osteoporosis in elderly pa-tients with type 2 diabetes were 0.851,0.772 and 0.904,respectively.Multivariate Logistic regression analysis showed that long duration of diabetes,increased HbA1c,high expression of OC,CHI3L1＞4.16 ng/mL,SDC1≥50.94 ng/mL were all influential factors for osteoporosis in elderly patients with type 2 diabetes(P＜0.05).Conclusion Low expression of CHI3L1 and high expression of SDC1 in serum are associated with ab-normal bone metabolism in elderly patients with type 2 diabetes.These two indexes are expected to be used as biological markers to predict osteoporosis in elderly patients with type 2 diabetes.

Objective:To revise the quality standards of pharmaceutical excipients egg yolk lecithin and egg yolk lecithin(for injection)in Chinese Pharmacopoeia of 2025.Methods:Study on the quality of egg yolk lecithin by research on the crucial quality attributes and comparing domestic and abroad quality standards in pharmacopoeias.Results:Identification,water,residual solvents,and assay have been revised and free fatty acids has been deleted in the quality standard for egg yolk lecithin.Identification,water,residual solvents,related substances,bacterial endotoxins,and assay have been revised and free fatty acids has been deleted in the quality standard for egg yolk lecithin(for injection).Conclusion:The revised quality standards for egg yolk lecithin and egg yolk lecithin(for injection)have been included in the Chinese Pharmacopoeia of 2025,which provide data support and basis for qual-ity control and scientific supervision of egg yolk lecithin.

Objective To understand the current situation of healthcare-associated infection(HAI)in China,pro-vide data support and decision-making basis for formulating scientific and effective strategies for HAI prevention and control.Methods A nationwide cross-sectional survey on HAI was conducted among various types and levels of medical institutions in China according to a unified protocol of bedside surveys and case investigations.Results In 2024,a total of 5 736 medical institutions and 2 751 765 patients were surveyed.Among them,34 889 HAI cases were identified,with a prevalence rate of 1.27％.The number of HAI episodes was 38 032,and case prevalence rate was 1.38％.The prevalence rate of HAI in medical institutions in different regions of China ranged from 0.66％to 2.35％.Among medical institutions of different scales,those with a bed capacity of ≥900 had the high-est incidence of HAI,reaching 1.65％.The most common infection site was the lower respiratory tract(44.66％),followed by the urinary tract(12.94％),surgical site(9.32％),upper respiratory tract(7.02％),and bloodstream infection(5.78％).The top 3 departments with the highest HAI rates were the general intensive care unit(10.02％),department of neurosurgery(5.51％),and department(group)of hematology(5.34％).A total of 23 238 strains of HAI pathogens were detected,with 10 714 strains(46.10％)from lower respiratory tract speci-mens.The top 5 detected strains were Klebsiella pneumoniae(14.76％),Pseudomonas aeruginosa(13.33％),Escherichia coli(12.79％),Acinetobacter baumannii(9.23％),and Staphylococcus aureus(7.88％).231 944 pa-tients underwent class Ⅰ incision surgery were monitored,with 1 647 cases experienced surgical site infection,and the prevalence rate of surgical site infection was 0.71％.The number of patients who should undergo pathogen de-tection(patients receiving therapeutic and therapeutic combined prophylactic antimicrobial agents)was 715 179,while the actual number was 480 492,with a pathogen detection rate of 67.18％.425 225 patients received patho-genic detection before treatment,with a detection rate of 59.46％.Conclusion The overall HAI prevalence in Chi-na is lower,showing disparities among medical institutions of different regions and scales.Therefore,precise imple-mentation of measures is necessary for HAI prevention and control,with a focus on high-risk institutions and high-risk departments,key areas,and critical procedures.All levels of medical institutions should continuously reduce the incidence of HAI by strengthening monitoring,standardizing the use of antimicrobial agents,and reinforcing basic HAI prevention and control measures.

This study aimed to investigate the potential mechanism and the compatibility significance of Tanyu Tongzhi Formula in treating atherosclerosis(AS) in mice based on the transforming growth factor-β(TGF-β)/Smad2/3 signaling pathway. Eight C57BL/6J mice were as assigned to a normal control group and fed a regular diet, while 35 ApoE~(-/-) mice of the same strain were fed a high-fat diet for 8 weeks to establish an AS model. The model mice were randomly divided into a model group, a Tanyu Tongzhi group(18.2 mg·kg~(-1)), a Huatan(phlegm-resolving) group(10.4 mg·kg~(-1)), and a Quyu(blood stasis-resolving) group(7.8 mg·kg~(-1)), with 8 mice in each group. Except for the normal group, all other groups continued to be fed a high-fat diet for 8 weeks to maintain the AS model, and then the mice were treated by gavage for 8 weeks. Plasma levels of total cholesterol(TC), triglycerides(TG), low-density lipoprotein cholesterol(LDL-C), high-density lipoprotein cholesterol(HDL-C), interleukin-1β(IL-1β), and interleukin-18(IL-18) were measured using enzyme-linked immunosorbent assay(ELISA). Hematoxylin and eosin(HE) staining, oil red O staining, and Russell-Movat pentachrome staining were performed to observe the pathological changes in the aortic tissue. The proportions of aortic plaque area, lipid-stained area, collagen fibers, and elastic fibers were calculated. Immunofluorescence was used to detect the protein expression levels of matrix metalloproteinase 2(MMP2) and tissue inhibitor of metalloproteinases 2(TIMP2). Western blot was used to detect the protein expression levels of TGF-β1, TGF-β2, Smad2/3, and Smad7 in aortic tissue. Real-time fluorescence quantitative PCR(RT-qPCR) was used to measure the mRNA expression levels of TGF-β receptor(TGF-βR), TGF-β1, Smad2/3, Smad7, intercellular adhesion molecule-1(ICAM-1), and vascular cell adhesion molecule-1(VCAM-1) in aortic tissue. The results showed that compared with the normal control group, the model group had increased plasma TC and LDL-C, significantly decreased HDL-C, and significantly elevated plasma IL-1β and IL-18 levels. The model group also exhibited an increased proportion of aortic plaque area, lipid-stained area, and collagen fiber area, along with significantly upregulated MMP2 and downregulated TIMP2 expression in the aortic arch. Additionally, the expression levels of TGF-βR, TGF-β1, and p-Smad2/3 proteins and mRNA in the aortic tissue were significantly elevated, while Smad7 expression was decreased. Compared with the model group, the Tanyu Tongzhi group showed significantly reduced plasma TC and LDL-C levels, significantly increased HDL-C levels, and significantly decreased plasma IL-1β and IL-18 levels. The Tanyu Tongzhi group also exhibited a significant reduction in aortic plaque size and severity, a significant downregulation of MMP2 expression in the aortic arch, and significantly decreased ICAM-1 and VCAM-1 mRNA expression levels. Moreover, the Tanyu Tongzhi group demonstrated significantly reduced expression levels of TGF-β1 and p-Smad2/3 proteins and mRNA in the aortic tissue, and an increased expression level of Smad7 protein to varying degrees. Compared with the Tanyu Tongzhi group, the Quyu group had significantly higher LDL-C levels and elevated plasma IL-1β and IL-18 levels. The Huatan group showed upregulated MMP2 expression and downregulated TIMP2 expression in the aortic arch. In conclusion, Tanyu Tongzhi Formula, which is composed based on the pathogenesis of phlegm and blood stasis, maintains vascular homeostasis by primarily regulating lipid metabolism and controlling inflammatory factors through the Huatan group, and maintaining vascular wall permeability, inhibiting plaque development, and stabilizing plaques through the Quyu group. The mechanism of action may involve inhibiting TGF-β1 expression in the aorta, reducing Smad2/3 phosphorylation, and simultaneously increasing Smad7 expression.
Animals ; Atherosclerosis/metabolism* ; Signal Transduction/drug effects* ; Drugs, Chinese Herbal/administration & dosage* ; Mice ; Mice, Inbred C57BL ; Male ; Transforming Growth Factor beta/genetics* ; Humans ; Homeostasis/drug effects* ; Aorta/metabolism* ; Smad2 Protein/genetics* ; Smad3 Protein/genetics*