In this study, we constructed a GLP-2R-HEK293 cell line and established a method for the determination of the in vitro biological activity of teduglutide based on HTRF, after optimizing experimental conditions and methodological verification. We also carried out relative potency detection of teduglutide pharmaceutical products using this method. The result showed that there was a quantitative-efficient relationship between the teduglutide activity and cAMP contents in GLP-2R-HEK293 cells, which conformed to four-parameter model. Method verification results of five concentrations of teduglutide (64%, 80%, 100%, 125% and 156%) met the requirements of the General Rules of Chinese Pharmacopoeia, 2020 edition, Volume IV (9401). We then analyzed the relative potency of three batches of teduglutide drug substances and three batches of drug products. The linearity, regression and parallelism of the obtained curves all fit the system suitability requirements. The relative potency of six batches of teduglutide was from 83% to 105%. In summary, the biological activity detection method established in this study was accurate, precise, simple and time-saving, which can be used for quality control of teduglutide pharmaceutical products.

This study constructed a LHCGR-CRE-luc-HEK293 transgenic cell line according to the activation of the cAMP signaling pathway after recombinant human chorionic gonadotropin binding to the receptor. The biological activity of recombinant human chorionic gonadotropin was assayed using a luciferase assay system. The relative potency of the samples was calculated using four-parameter model. And the method conditions were optimized to validate the specificity, relative accuracy, precision and linearity of the method. The results showed that there was a quantitative potency relationship of human chorinonic gonadotropin (hCG) in the method and it was in accordance with the four-parameter curve. After optimization, the conditions were determined as hCG dilution concentration of 2.5 μg·mL^-1, dilution ratio of 1∶4, cell number of 10 000-15 000 cells/well, and induction time of 6 h. The method had good specificity, relative accuracy with relative bias ranging from -8.9% to 3.4%, linear regression equation correlation coefficient of 0.996, intermediate precision geometric coefficient of variation ranging from 3.3% to 15.0%, and linearity range of 50% to 200%. This study successfully established and validated a reporter gene method to detect hCG biological activity, which can be used for hCG biological activity assay and quality control.

The correct pairing of disulfide bonds maintains the correct folding mode and high-level structure formation of peptides and protein drugs, which is crucial for the quality control of products. In order to ensure that the disulfide bonds are correctly paired, disulfide bond analysis is an essential part of peptides and protein drug characterization. Mass spectrometry can be used to analyze disulfide bonds. However, insulin and its analogues have two pairs of disulfide bonds without restriction enzyme cutting site. Conventional collision-induced dissociation (CID) and high-energy induced cleavage (HCD) cannot accurately locate the complex disulfide bond. In our study, three methods were used to localize the complex disulfide, including enzyme digestion combined with key peptide fragment in source decay (ISD) fragmentation method, enzyme digestion combined with partial reduction alkylation method, intact protein source ISD and electron transfer dissociation (ETD) cleavage method, The applicability of insulin aspart, insulin lispro and insulin glargine were also investigated. This study provides a new way for the quality control of disulfide bonding mode of insulin and its analogues, and also provides a reference for the disulfide bond localization of peptides or proteins containing this complex disulfide bond.

AIM To investigate the variation rules of main secondary metabolites in Hedysari Radix before and after rubbing strip.METHODS UPLC-MS/MS was adopted in the content determination of formononetin,ononin,calycosin,calycosin-7-glucoside,medicarpin,genistein,luteolin,liquiritigenin,isoliquiritigenin,vanillic acid,ferulic acid,γ-aminobutyric acid,adenosine and betaine,after which cluster analysis,principal component analysis and orthogonal partial least squares discriminant analysis were used for chemical pattern recognition to explore differential components.RESULTS After rubbing strip,formononetin,calycosin,liquiritigenin and γ-aminobutynic acid demonstrated increased contents,along with decreased contents of ononin,calycosin-7-glucoside and vanillic acid.The samples with and without rubbing strip were clustered into two types,calycosin-7-glucoside,formononetin,γ-aminobutynic acid,vanillic acid,calycosin-7-glucoside and formononetin were differential components.CONCLUSION This experiment clarifies the differences of chemical constituents in Hedysari Radix before and after rubbing strip,which can provide a reference for the research on rubbing strip mechanism of other medicinal materials.

Objective To develop a matrix metalloproteinase(MMP)-responsive hyaluronic acid(HA)-based controlled-release material for brain-derived neurotrophic factor(BDNF)to provide a novel therapeutic strategy for intervention and repair of traumatic brain injury(TBI).Methods HA was modified with amination,followed by condensation with Suflo-SMCC carboxyl group to form amide,and then linked with glutathione(GSH)to synthesize HA-GSH.The recombinant glutathione S-transferase(GST)-tissue inhibitor of metalloproteinase(TIMP)-BDNF(GST-TIMP-BDNF)expression plasmid was constructed using molecular cloning technique with double enzyme digestion by Bam H Ⅰ and Eco R Ⅰ.The recombinant GST-TIMP-BDNF protein was expressed in the Escherichia coli prokaryotic expression system,and purified by ion exchange chromatography,confirmed by Western blotting.MMP diluents were supplemented with PBS,MMP inhibitor marimastat,and varing concentrations(0.4,0.6,0.8 mg/ml)of GST-TIMP-BDNF or GST-BDNF.MMP-2 activity was analyzed using an MMP activity detection kit to evaluate the inhibitory effect of the recombinant protein on MMP.Primary rat neurons were extracted and cultured to establish an iron death model induced by RSL3.The effect of recombinant protein GST-TIMP-BDNF on neuronal injury was detected by immunofluorescence staining.Results MRI hydrogen spectrum identification confirmed the successful synthesis of HA-GSH.Western blotting results showed the successful expression of the recombinant protein GST-TIMP-BDNF containing the GST tag using the E.coli prokaryotic expression system.MMP activity detection results indicated that the recombinant protein GST-TIMP-BDNF had a superior inhibitory effect on MMP-2 activity compared to GST-BDNF(P<0.05).Immunofluorescence staining results showed a significant increase in fluorescence intensity in rat neurons treated with GST-TIMP-BDNF after RSL3 induction(P<0.05).Conclusion A MMP-responsive HA-based BDNF controlled-release material has been successfully developed,exhibiting a protective effect on neuron damage.

Purpose::The reconstruction of Allen's type IV fingertip amputation is a clinical challenge. Our team designed bilateral unequal-sized hallux osteo-onychocutaneous free flaps for the long-term reconstruction of Allen's type IV fingertip amputation and conducted a retrospective study with a 5-year follow-up aims to evaluate the effects of this technique.Methods::A retrospective analysis with a 5-year follow-up including 13 patients with Allen's type IV fingertip amputation who were admitted to our hospital from January 2010 to January 2017 was conducted. The patients were treated with bilateral unequal-sized hallux osteo-onychocutaneous free flaps. The operation time, intraoperative blood loss, and complications were recorded, and the survival rate of the transplanted flaps was calculated. During the 5-year follow-up after operation, the nail growth time was recorded and the finger appearance was observed. At the last follow-up appointment, the length, width, and girth of the reconstructed fingertip and contralateral normal fingertip, range of motion of the reconstructed fingertip and contralateral normal fingertip, Semmes-Weinstein test (for the evaluation of tactile sensation), and two-point discrimination testing results were recorded. SPSS 22.0 software was used for the statistical analysis and the data are presented as mean ± SD.Results::The mean operation time was (5.62 ± 0.51) h, the mean intraoperative blood loss was (34.15 ± 3.13) mL, and the survival rate of the transplanted flaps was 100%. During the 5-year follow-up, the average nail growth time was (10.14 ± 1.98) months and the average bone union time was (3.78 ± 0.91) months. The length, width, and girth of the reconstructed fingertip were (31.52 ± 3.73) mm, (17.82 ± 1.74) mm, and (59.75 ± 3.04) mm, respectively, which did not differ from those of the contralateral normal fingertip. The range of motion of the reconstructed fingertip was (12.15 ± 2.79) degrees which is different from that of the contralateral normal fingertip. The average tactile sensation evaluated via the Semmes-Weinstein test and the average two-point discrimination test of the reconstructed fingertip were (0.39 ± 0.17) g and (7.46 ± 1.14) mm, respectively, which were not different from those of the contralateral normal fingertip. The average Maryland score of feet in the donor area was 87.66 ± 7.39, which was satisfactory.Conclusion::Bilateral unequal-sized hallux osteo-onychocutaneous free flaps are an effective method to reconstruct Allen's type IV fingertip amputations with a satisfactory appearance and good sensory function.

The Dionex CaboPac^TM PA10 BioLC^TM Analyical 2 mm × 250 mm column was used with a protective column (Dionex CaboPac^TM PA10 BioLC^TM Guard 2 mm × 50 mm). 100 mmol·L^-1 sodium hydroxide solution was used as eluent; the flow rate was 0.25 mL·min^-1. Sample tray temperature: 35 ℃. The pulse amperometric detector was adopted, and the waveform was Gold CWE, Ag-AgCl RE, Carbo, Quad. The samples were cultured with 8 concentrations of glycogen substrates (0.31, 1.25, 2.5, 5, 10, 20, 30, and 40 mg·mL^-1). D-Glucose concentrations were measured at 5 different time points (T0, T1, T2, T3 and T4). The glucose concentration from T1 to T4 minus the glucose concentration at T0. The reaction rate was calculated at different glycogen substrate concentrations. These reaction rates are plotted against substrate concentrations using Michaelis-Menten equation. The kinetic parameters were expressed as V_max (nmol·mg^-1·min^-1) and K_m (mg·mL^-1). The RSD of glucose standard curve R² (n = 6, linear range: 1.25-500 μmol·L^-1) was 0.1% and the RSD (n = 6) of the slope of the standard curve was 2.2%. The mean limit of quantitation was 0.14 μmol·L^-1, and the mean limit of detection was 0.05 μmol·L^-1. The RSD of K_m and V_max were 4.4% and 4.6% respectively in three separate experiments. The durability of the method was good. The method was developed for the on-line automatic determination of the hydrolysis kinetics of acid α-glucosidase (GAA) for injection by ion chromatography. The method has good precision, repeatability and durability, and can be used for the determination of glycogen hydrolysis kinetics of GAA for injection, and could reference value for the enzyme kinetics evaluation of recombinant enzyme replacement therapy.

According to the requirements of the regulatory authorities, degree of modification (DP) should be included in the characterisation of the PEGylated protein drug substance, and is one of the critical quality attributes for quality control. In this study, based on the fundamental assumption that the refractive index (RI) signal and the ultraviolet (UV) signal of PEGylated protein are equal to the sum of the corresponding signal produced by the polyethylene glycol (PEG) and protein parts of the conjugates in their uncoupled state, we developed a method to determine the DP of PEGylated recombinant human growth hormone (inpegsomatropin). In this method, 20 μL of 1 mg·mL^-1 human growth hormone (hGH) standard, 2 mg·mL^-1 PEG reference substance and 1 mg·mL^-1 drug substance solution were each injected to size exclusion chromatographic (SEC) column for separation, detected with ultraviolet and refractive index (UV-RI) detectors in series. Finally, the DP was calculated as the formula derived from the fundamental assumption. The developed SEC-UV-RI method showed good specificity, repeatability (RSD = 0.63%, n = 9) and accuracy, with a recovery of 100.0%, compared with the result obtained from the simultaneously established classical acid hydrolysis method, demonstrating pretty handleability and accessibility, and is appropriate for quality control test of DP for this drug substance.

Humans ; Consensus ; Pancreatic Neoplasms/therapy* ; Neuroendocrine Tumors/therapy*

Aim To investigate the effects of daidzeinDD on the proliferation and apoptosis of non-small cell lung cancer cells,with a focus on the possible role of the p53 signaling pathway in this regard. Methods CCK-8 method and flow cytometry were used to detect the effects of soy isoflavone crude extract and DD on the viability and apoptosis of HELF and H1299 cells. Gene microarray was used to detect the changes in gene expression after treatment of H1299 cells with DD. GSEA and differential analysis were used to screen the major pathways and key genes. RT-qPCR and Western blot were performed to verify the differences in mRNA and protein expression of key genesp53 and CASP9 in the major pathways. After p53 inhibitor Pifithrin-α inhibited the expression of p53,the effect of DD on p53 mRNA and protein expression levels was examined,and the proliferative effect on H1299 cells was observed. Results Soy isoflavone crude extract and DD promoted proliferation and inhibited apoptosis of normal lung cells and inhibited proliferation and promoted apoptosis of lung cancer cells. p53 signaling pathway was significantly enriched in the DD-treated groupNES=1.78,P=0.000,and the expressions of p53 and CASP9 genes were found to be significantly up-regulated in the treated group. Compared with the control group,mRNA expression of CASP9 and p53 significantly increased in both HELF and H1299 cells treated with DDP<0.05,and p53 protein expression also increased in HELF cellsP<0.05. After inhibition of p53 expression,DD significantly increased the mRNA expression of p53 in H1299 and HELF cellsP<0.05 and also markedly increased the expression of p53 protein in H1299 cellsP<0.05,and it was observed that DD inhibited the proliferation of lung cancer cells. Conclusions DD inhibits the proliferation and promotes the apoptosis of lung cancer H1299 cells,and the mechanism mainly involves the p53 signaling pathway.