Peptide-drug conjugates (PDCs) have emerged as a promising modality in precision oncology, enabling targeted delivery of cytotoxic payloads while minimizing off-target toxicity. The integration of covalent warheads, such as those based on sulfur(VI) fluoride exchange (SuFEx) chemistry, enhances drug-target residence time and tumor accumulation. However, existing screening methods for covalent peptide (CP) libraries require post-translational warhead conjugation, limiting throughput. Here, we present an integrated mRNA display platform that incorporates covalent warheads during ribosomal synthesis, enabling efficient screening of ultra-diverse covalent macrocyclic peptide libraries (>10¹³ variants). This approach, using site-specific incorporation of N-chloroacetyl-d-phenylalanine and fluorosulfate-l-tyrosine, accelerated the discovery of irreversibly binding (K _i = 3.58 μmol/L) Nectin-4-targeting peptide CP-N1-N₃ via proximity-triggered SuFEx. The peptide was further conjugated to cytotoxic payloads, yielding the covalent PDC CP-N1-MMAE with potent cytotoxicity (IC₅₀ ≈ 43 nmol/L) against MDA-MB-468 cells. This platform establishes a new paradigm for precision covalent drug discovery.

BACKGROUND:D1-3-n-butylphthalide has antioxidant and anti-inflammatory effects and has been explored to have protective role in Parkinson's disease,but the underlying mechanisms are unknown.OBJECTIVE:To investigate the protective effect of D1-3-n-butylphthalide by the approach of network pharmacology,molecular docking,and cellular experimental validation.METHODS:(1)Network pharmacology and molecular docking:The database was used to screen the targets of D1-3-n-butylphthalide and Parkinson's disease.The intersection was taken from the construction of the target protein interaction network,and then screen the core targets.The GO and KEGG pathway enrichment was used to further analyze the core targets.The interaction between the target proteins and D1-3-n-butylphthalide was verified by molecular docking.(2)Cell validation:The passage 6 PC12 cells were divided into six groups for culture.The control group was cultured with conventional culture medium.The model group was cultured with N-methyl-4-phenylpyridinium iodide to induce Parkinson's disease model.The ML385 inhibitor group was added with nuclear factor E2-related factor 2 inhibitor ML385 on the basis of inducing Parkinson's disease model.The D1-3-n-butylphthalide treatment group was added with butylphthalide on the basis of inducing Parkinson's disease model.The D1-3-n-butylphthalide combined with ML385 treatment group was added with D1-3-n-butylphthalide and ML385 on the basis of inducing Parkinson's disease model.The D1-3-n-butylphthalide group was cultured with conventional culture medium containing butylphthalide alone.Cell proliferation,intracellular reduced glutathione and malondialdehyde levels,and protein expression of protein kinase B/glycogen synthase kinase 3β/nuclear factor E2-related factor 2(AKT/GSK-3β/Nrf2)signaling pathway were detected.RESULTS AND CONCLUSION:(1)A total of 52 targets were screened for the intersection of drugs and disease targets,and the core targets including the matrix metalloproteinase 9 and GSK-3β were involved the phosphatidylinositol 3-kinase(PI3K)/AKT and oxidative stress-related signaling pathways.The molecular docking binding energy of D1-3-n-butylphthalide and GSK-3β was-18.27 kJ/mol,which indicated that D1-3-n-butylphthalide had a good binding ability with GSK-3β.(2)Compared with the model group,the PC12 cell activity and reduced glutathione level in the D1-3-n-butylphthalide treatment group were increased(P＜0.05),the malondialdehyde level was decreased(P＜0.05),and the expression of p-AKT,p-GSK-3β,Nu-Nrf2,and T-Nrf2 proteins was increased(P＜0.05).Compared with the D1-3-n-butylphthalide group,the PC12 cell activity and reduced glutathione level in the D1-3-n-butylphthalide combined with ML385 treatment group were decreased(P＜0.05),the malondialdehyde level was increased(P＜0.05),and the expression of Nu-Nrf2 and T-Nrf2 proteins was decreased(P＜0.05).(3)These results demonstrate that D1-3-n-butylphthalide can inhibit oxidative stress and improve cell activity through the AKT/GSK-3β/Nrf2 signaling pathway,and has a protective effect on the Parkinson's cell model induced by N-methyl-4-phenylpyridinium iodide.

BACKGROUND:D1-3-n-butylphthalide has antioxidant and anti-inflammatory effects and has been explored to have protective role in Parkinson's disease,but the underlying mechanisms are unknown.OBJECTIVE:To investigate the protective effect of D1-3-n-butylphthalide by the approach of network pharmacology,molecular docking,and cellular experimental validation.METHODS:(1)Network pharmacology and molecular docking:The database was used to screen the targets of D1-3-n-butylphthalide and Parkinson's disease.The intersection was taken from the construction of the target protein interaction network,and then screen the core targets.The GO and KEGG pathway enrichment was used to further analyze the core targets.The interaction between the target proteins and D1-3-n-butylphthalide was verified by molecular docking.(2)Cell validation:The passage 6 PC12 cells were divided into six groups for culture.The control group was cultured with conventional culture medium.The model group was cultured with N-methyl-4-phenylpyridinium iodide to induce Parkinson's disease model.The ML385 inhibitor group was added with nuclear factor E2-related factor 2 inhibitor ML385 on the basis of inducing Parkinson's disease model.The D1-3-n-butylphthalide treatment group was added with butylphthalide on the basis of inducing Parkinson's disease model.The D1-3-n-butylphthalide combined with ML385 treatment group was added with D1-3-n-butylphthalide and ML385 on the basis of inducing Parkinson's disease model.The D1-3-n-butylphthalide group was cultured with conventional culture medium containing butylphthalide alone.Cell proliferation,intracellular reduced glutathione and malondialdehyde levels,and protein expression of protein kinase B/glycogen synthase kinase 3β/nuclear factor E2-related factor 2(AKT/GSK-3β/Nrf2)signaling pathway were detected.RESULTS AND CONCLUSION:(1)A total of 52 targets were screened for the intersection of drugs and disease targets,and the core targets including the matrix metalloproteinase 9 and GSK-3β were involved the phosphatidylinositol 3-kinase(PI3K)/AKT and oxidative stress-related signaling pathways.The molecular docking binding energy of D1-3-n-butylphthalide and GSK-3β was-18.27 kJ/mol,which indicated that D1-3-n-butylphthalide had a good binding ability with GSK-3β.(2)Compared with the model group,the PC12 cell activity and reduced glutathione level in the D1-3-n-butylphthalide treatment group were increased(P＜0.05),the malondialdehyde level was decreased(P＜0.05),and the expression of p-AKT,p-GSK-3β,Nu-Nrf2,and T-Nrf2 proteins was increased(P＜0.05).Compared with the D1-3-n-butylphthalide group,the PC12 cell activity and reduced glutathione level in the D1-3-n-butylphthalide combined with ML385 treatment group were decreased(P＜0.05),the malondialdehyde level was increased(P＜0.05),and the expression of Nu-Nrf2 and T-Nrf2 proteins was decreased(P＜0.05).(3)These results demonstrate that D1-3-n-butylphthalide can inhibit oxidative stress and improve cell activity through the AKT/GSK-3β/Nrf2 signaling pathway,and has a protective effect on the Parkinson's cell model induced by N-methyl-4-phenylpyridinium iodide.

Objective To analyze the current situation of human resources in county-level specialized disease prevention and control institutions in Guangdong Province in 2022 and propose countermeasures.Methods Analyze the human resources situation of specialized disease prevention and control personnel in counties in Guangdong Province based on their basic informa-tion such as staffing,age,professional title,and income level.Results The education level of county-level specialized disease prevention and control personnel in Guangdong Province is mainly undergraduate(42.60％),the technical title is mainly inter-mediate or below(84.08％),and the age is mainly over 45 years old(39.58％);Comparative analysis was conducted on the education and professional titles of specialized disease prevention and control personnel in counties in the Pearl River Delta,east-ern Guangdong,western Guangdong,and northern Guangdong regions,and the differences were statistically significant(x2=733.751,P＜0.001;x2=142.048,P＜0.001).Conclusion The human resources for specialized disease prevention and control in counties in Guangdong Province are facing problems such as talent shortage,aging of personnel,low academic qualifi-cations and titles,and insufficient financial investment.It is recommended to formulate a scientific and reasonable talent develop-ment plan,attach importance to and strengthen the construction of specialized disease prevention and control talent teams.

Objective To evalute the drug resistance characteristics of tuberculosis(TB)patients of all ages in Guangdong Province during 2014-2020,and provide prevention and treatment strategies of tuberculosis.Method We used 39,048 clinical isolates of Mycobacterium tuberculosis(MTB)belonging to patients with confirmed TB from 2014 to 2020,from 32 TB drug-resistant surveillance sites in Guangdong Province,and we retrospectively analyzed the laboratories data of patients with drug-resistant TB,and grouped patients by age and region,to explore the trend of drug-resistance of MTB clinical isolates,the trend and incidence differences of multi-resistant TB(including monodrug-resistant TB(MR-TB),polydrug-resistant TB(PDR-TB),multidrug-resistant TB(MDR-TB)and exten-sively drug-resistant TB(XDR-TB)),and resistance characteristics of MTB clinical isolates to drugs in focus(rifam-picin and ofloxacin).Result The differences in the resistance rates of MTB clinical isolates to nine antituberculosis drugs among patients at 32 TB drug resistance surveillance sites in Guangdong Province from 2014 to 2020 were not statistically significant(P>0.05).The rates of MR-TB,PDR-TB,MDR-TB,XDR-TB,and total resistance isolates of MTB clinical isolates were 14.46%,5.16%,5.16%,4.58%,and 1.29%,respectively.he pediatric group had a higher MR rate(15.4%)than the adult and geriatric groups,while the adult and geriatric groups had higher MDR rates(5.0%and 5.0%,respectively).The geriatric group also had a higher XDR rate(2.1%),with statistically significant differences(P<0.001).The rates of MR-TB(14.8%),PDR-TB(5.3%),MDR-TB(4.7%),XDR-TB(1.4%),ofloxacin resistance(11.33%)and rifampicin resistance(6.92%)of MTB clinical isolates were higher in patients from the Pearl River Delta than in other regions of Guangdong Province,with statistically significant differ-ences(P<0.001).Conclusion According to the data from the surveillance sites,the epidemiological trend of drug-resistant TB in Guangdong Province is leveling off during the period 2014-2020.However,the incidence of drug-resistant TB is higher in specific populations(e.g.children and the elderly),and the incidence of drug-resistant TB and the rate of drug resistance to drugs in focus are higher in the Pearl River Delta than in other regions of Guang-dong Province,necessitating further investigation and the development of novel prevention and control strategies.

Objective To analyze the current situation of human resources in county-level specialized disease prevention and control institutions in Guangdong Province in 2022 and propose countermeasures.Methods Analyze the human resources situation of specialized disease prevention and control personnel in counties in Guangdong Province based on their basic informa-tion such as staffing,age,professional title,and income level.Results The education level of county-level specialized disease prevention and control personnel in Guangdong Province is mainly undergraduate(42.60％),the technical title is mainly inter-mediate or below(84.08％),and the age is mainly over 45 years old(39.58％);Comparative analysis was conducted on the education and professional titles of specialized disease prevention and control personnel in counties in the Pearl River Delta,east-ern Guangdong,western Guangdong,and northern Guangdong regions,and the differences were statistically significant(x2=733.751,P＜0.001;x2=142.048,P＜0.001).Conclusion The human resources for specialized disease prevention and control in counties in Guangdong Province are facing problems such as talent shortage,aging of personnel,low academic qualifi-cations and titles,and insufficient financial investment.It is recommended to formulate a scientific and reasonable talent develop-ment plan,attach importance to and strengthen the construction of specialized disease prevention and control talent teams.

OBJECTIVE To establish comprehensive quality evaluation method based on multi-index components combined with multivariate statistical analysis， and to comprehensively evaluate the quality of Periploca forrestii. METHODS Taking 11 batches of P. forrestii medicinal materials from different areas in Guizhou as samples， the contents of neochlorogenic acid， cryptochlorogenic acid， chlorogenic acid， procyanidin A2， isochlorogenic acid A and isochlorogenic acid C were determined by HPLC. Clustering heat map analysis， grey correlation analysis（GRA） and technique for order preference by similarity to ideal solution（TOPSIS） were used to evaluate the quality of P. forrestii. RESULTS The results of methodological investigation of content determination were in accordance with the relevant regulations， and the linear relationship and accuracy of each component were good in their respective sampling range. The contents of chlorogenic acid， cryptochlorogenic acid， neochlorogenic acid， procyanidin A2， isochlorogenic acid A and isochlorogenic acid C in 11 batches of samples were 3.650-7.302， 0.888-2.575， 1.371- 2.386， 0.947-1.469， 0.084-0.169 and 0.725-1.067 mg/g， respectively. The content of each component was significantly different， with the highest content of chlorogenic acid and the lowest content of isochlorogenic acid A. The comprehensive results of cluster heat map， GRA and TOPSIS analysis showed that the comprehensive quality of S5 and S10 was relatively good. CONCLUSIONS The established method is accurate， stable and simple. Combined with multivariate statistical analysis method， it can be used for quality evaluation of P. forrestii. The quality of samples from Jiuzhou Town and Caiguan Town of Xixiu District in Anshun City of Guizhou Province are relatively good among 11 different origin samples.

Objective:Establishment of a new model of human primary colon cancer transplantation tumor in normal immune mice and to provide a reliable experimental animal model for studying the pathogenesis of colon cancer under normal immunity.Methods:Human colon cancer cells come from colon cancer patients who underwent surgery in the Affiliated Hospital of Jining Medical College in 2017. The mice in the cell control group were inoculated with phosphate buffered solution (PBS) containing colon cancer cells, the microcarrier control group was inoculated with PBS containing microcarrier 6, and the cell-microcarrier complex group was inoculated with the PBS containing colon cancer cell-microcarrier complex. The cells of each group were inoculated under the skin of the right axilla of mice by subcutaneous injection, and the time, size, tumor formation rate and pathological changes under microscope were recorded. The transplanted tumor tissue was immunohistochemically stained with the EnVisiion two-step method, and the tumor formation rate of the transplanted tumor was judged according to the proportion of positive cells in the visual field. The polymerase chain reaction (PCR) method was used to detect the expression of human-specific Alu sequence in mice tumor tissue.Results:After inoculation with tumor cells, the mice in the cell control group and the microcarrier control group did not die and did not form tumors; the mice in the cell-microcarrier complex group had palpable subcutaneous tumors in the right axillary subcutaneously on the 5th to 7th days after inoculation, and tumor formation rate is 67% (10/15), and the tumor volume can reach about 500 mm 3 2 to 3 weeks after vaccination. The immunohistochemistry results showed that CK20, CDX-2 and carcinoembryonic antigen were all positively expressed. The PCR results showed that the expression of human-specific Alu sequence can be detected in the transplanted tumor tissue of tumor-bearing mice. Conclusion:Human primary colon cancer cells used microcarrier 6 as a carrier to form tumors in normal immunized mice, and successfully established a new model of human colon cancer transplantation tumor in normal immune mice.

Objective:Establishment of a new model of human primary colon cancer transplantation tumor in normal immune mice and to provide a reliable experimental animal model for studying the pathogenesis of colon cancer under normal immunity.Methods:Human colon cancer cells come from colon cancer patients who underwent surgery in the Affiliated Hospital of Jining Medical College in 2017. The mice in the cell control group were inoculated with phosphate buffered solution (PBS) containing colon cancer cells, the microcarrier control group was inoculated with PBS containing microcarrier 6, and the cell-microcarrier complex group was inoculated with the PBS containing colon cancer cell-microcarrier complex. The cells of each group were inoculated under the skin of the right axilla of mice by subcutaneous injection, and the time, size, tumor formation rate and pathological changes under microscope were recorded. The transplanted tumor tissue was immunohistochemically stained with the EnVisiion two-step method, and the tumor formation rate of the transplanted tumor was judged according to the proportion of positive cells in the visual field. The polymerase chain reaction (PCR) method was used to detect the expression of human-specific Alu sequence in mice tumor tissue.Results:After inoculation with tumor cells, the mice in the cell control group and the microcarrier control group did not die and did not form tumors; the mice in the cell-microcarrier complex group had palpable subcutaneous tumors in the right axillary subcutaneously on the 5th to 7th days after inoculation, and tumor formation rate is 67% (10/15), and the tumor volume can reach about 500 mm 3 2 to 3 weeks after vaccination. The immunohistochemistry results showed that CK20, CDX-2 and carcinoembryonic antigen were all positively expressed. The PCR results showed that the expression of human-specific Alu sequence can be detected in the transplanted tumor tissue of tumor-bearing mice. Conclusion:Human primary colon cancer cells used microcarrier 6 as a carrier to form tumors in normal immunized mice, and successfully established a new model of human colon cancer transplantation tumor in normal immune mice.

Ob jectiev Oxidized low-density lipoprotein ( ox-LDL) induces vascular endothelial cell injury , which is one of the factors initiating atherosclerosis .This study aimed to investigate the protective effect of Tongxinluo ( TXL ) on vascular endothelial cells with ox-LDL-induced injury . Methods Human umbilical vein endothelial cells ( HUVEC ) were cultured in vitro and divided into five groups:normal control, oxidative stress injury (OSI) model, and high, medium and low dose TXL.The HUVECs were incubated with ox-LDL at the concentration of 30 mg/L for 24 hours to induce oxidative stress injury and then treated with TXL at 50, 100 and 150 mg/L for 4 hours, followed by 24 hour incubation with 30 mg/L ox-LDL added to the culture medium .The viability of the cells was detected by MTS assay, the nitric oxide (NO) content, superoxide dismutase (SOD) activity and mitochondrial membrane poten-tial ( MMP) in the cell culture supernatant were measured with respective kits , and the expressions of iNOS , MMP9, and NF-κBp65 proteins were determined by Western blot . Results The HUVECs of the OSI model group showed a significant decrease in cell via-bility compared with the normal control , ([73 .89 ±0.67] vs [100.00 ±2.23]%, P<0.01) but a remarkably increase after treated with medium and high dose TXL ([92.15 ±0.76]%and [ 97.19 ±1.45]%, P<0.01).The MMP, NO content, and SOD activity were markedly reduced in the model group (P<0.01) but elevated in the low, medium, and high dose TXL groups (P<0 .01).The expressions of the iNOS, MMP9, and NF-κBp65proteins were significantly up -regulated in the model group (P<0.01) but down reg-ulated in the low, medium, and high dose TXL groups (P<0.05).C on clusion TXL has the effects of anti-oxidation and anti-in-flammation and can protect vascular endothelial cells against ox-LDL-induced injury .